1 /*
2  * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/stat.h>
18 #include <sys/queue.h>
19 #include <sys/tree.h>
20 
21 #include <dirent.h>
22 #include <limits.h>
23 #include <stddef.h>
24 #include <string.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <time.h>
28 #include <fcntl.h>
29 #include <errno.h>
30 #include <unistd.h>
31 #include <sha1.h>
32 #include <zlib.h>
33 #include <fnmatch.h>
34 #include <libgen.h>
35 #include <uuid.h>
36 #include <util.h>
37 
38 #include "got_error.h"
39 #include "got_repository.h"
40 #include "got_reference.h"
41 #include "got_object.h"
42 #include "got_path.h"
43 #include "got_cancel.h"
44 #include "got_worktree.h"
45 #include "got_opentemp.h"
46 #include "got_diff.h"
47 
48 #include "got_lib_worktree.h"
49 #include "got_lib_sha1.h"
50 #include "got_lib_fileindex.h"
51 #include "got_lib_inflate.h"
52 #include "got_lib_delta.h"
53 #include "got_lib_object.h"
54 #include "got_lib_object_parse.h"
55 #include "got_lib_object_create.h"
56 #include "got_lib_object_idset.h"
57 #include "got_lib_diff.h"
58 #include "got_lib_gotconfig.h"
59 
60 #ifndef MIN
61 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
62 #endif
63 
64 #define GOT_MERGE_LABEL_MERGED	"merged change"
65 #define GOT_MERGE_LABEL_BASE	"3-way merge base"
66 
67 static mode_t		 apply_umask(mode_t);
68 
69 static const struct got_error *
70 create_meta_file(const char *path_got, const char *name, const char *content)
71 {
72 	const struct got_error *err = NULL;
73 	char *path;
74 
75 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
76 		return got_error_from_errno("asprintf");
77 
78 	err = got_path_create_file(path, content);
79 	free(path);
80 	return err;
81 }
82 
83 static const struct got_error *
84 update_meta_file(const char *path_got, const char *name, const char *content)
85 {
86 	const struct got_error *err = NULL;
87 	FILE *tmpfile = NULL;
88 	char *tmppath = NULL;
89 	char *path = NULL;
90 
91 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
92 		err = got_error_from_errno("asprintf");
93 		path = NULL;
94 		goto done;
95 	}
96 
97 	err = got_opentemp_named(&tmppath, &tmpfile, path, "");
98 	if (err)
99 		goto done;
100 
101 	if (content) {
102 		int len = fprintf(tmpfile, "%s\n", content);
103 		if (len != strlen(content) + 1) {
104 			err = got_error_from_errno2("fprintf", tmppath);
105 			goto done;
106 		}
107 	}
108 
109 	if (rename(tmppath, path) != 0) {
110 		err = got_error_from_errno3("rename", tmppath, path);
111 		unlink(tmppath);
112 		goto done;
113 	}
114 
115 done:
116 	if (fclose(tmpfile) == EOF && err == NULL)
117 		err = got_error_from_errno2("fclose", tmppath);
118 	free(tmppath);
119 	return err;
120 }
121 
122 static const struct got_error *
123 write_head_ref(const char *path_got, struct got_reference *head_ref)
124 {
125 	const struct got_error *err = NULL;
126 	char *refstr = NULL;
127 
128 	if (got_ref_is_symbolic(head_ref)) {
129 		refstr = got_ref_to_str(head_ref);
130 		if (refstr == NULL)
131 			return got_error_from_errno("got_ref_to_str");
132 	} else {
133 		refstr = strdup(got_ref_get_name(head_ref));
134 		if (refstr == NULL)
135 			return got_error_from_errno("strdup");
136 	}
137 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
138 	free(refstr);
139 	return err;
140 }
141 
142 const struct got_error *
143 got_worktree_init(const char *path, struct got_reference *head_ref,
144     const char *prefix, struct got_repository *repo)
145 {
146 	const struct got_error *err = NULL;
147 	struct got_object_id *commit_id = NULL;
148 	uuid_t uuid;
149 	uint32_t uuid_status;
150 	int obj_type;
151 	char *path_got = NULL;
152 	char *formatstr = NULL;
153 	char *absprefix = NULL;
154 	char *basestr = NULL;
155 	char *uuidstr = NULL;
156 
157 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
158 		err = got_error(GOT_ERR_WORKTREE_REPO);
159 		goto done;
160 	}
161 
162 	err = got_ref_resolve(&commit_id, repo, head_ref);
163 	if (err)
164 		return err;
165 	err = got_object_get_type(&obj_type, repo, commit_id);
166 	if (err)
167 		return err;
168 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
169 		return got_error(GOT_ERR_OBJ_TYPE);
170 
171 	if (!got_path_is_absolute(prefix)) {
172 		if (asprintf(&absprefix, "/%s", prefix) == -1)
173 			return got_error_from_errno("asprintf");
174 	}
175 
176 	/* Create top-level directory (may already exist). */
177 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
178 		err = got_error_from_errno2("mkdir", path);
179 		goto done;
180 	}
181 
182 	/* Create .got directory (may already exist). */
183 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
184 		err = got_error_from_errno("asprintf");
185 		goto done;
186 	}
187 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
188 		err = got_error_from_errno2("mkdir", path_got);
189 		goto done;
190 	}
191 
192 	/* Create an empty lock file. */
193 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
194 	if (err)
195 		goto done;
196 
197 	/* Create an empty file index. */
198 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
199 	if (err)
200 		goto done;
201 
202 	/* Write the HEAD reference. */
203 	err = write_head_ref(path_got, head_ref);
204 	if (err)
205 		goto done;
206 
207 	/* Record our base commit. */
208 	err = got_object_id_str(&basestr, commit_id);
209 	if (err)
210 		goto done;
211 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
212 	if (err)
213 		goto done;
214 
215 	/* Store path to repository. */
216 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
217 	    got_repo_get_path(repo));
218 	if (err)
219 		goto done;
220 
221 	/* Store in-repository path prefix. */
222 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
223 	    absprefix ? absprefix : prefix);
224 	if (err)
225 		goto done;
226 
227 	/* Generate UUID. */
228 	uuid_create(&uuid, &uuid_status);
229 	if (uuid_status != uuid_s_ok) {
230 		err = got_error_uuid(uuid_status, "uuid_create");
231 		goto done;
232 	}
233 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
234 	if (uuid_status != uuid_s_ok) {
235 		err = got_error_uuid(uuid_status, "uuid_to_string");
236 		goto done;
237 	}
238 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
239 	if (err)
240 		goto done;
241 
242 	/* Stamp work tree with format file. */
243 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
244 		err = got_error_from_errno("asprintf");
245 		goto done;
246 	}
247 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
248 	if (err)
249 		goto done;
250 
251 done:
252 	free(commit_id);
253 	free(path_got);
254 	free(formatstr);
255 	free(absprefix);
256 	free(basestr);
257 	free(uuidstr);
258 	return err;
259 }
260 
261 const struct got_error *
262 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
263     const char *path_prefix)
264 {
265 	char *absprefix = NULL;
266 
267 	if (!got_path_is_absolute(path_prefix)) {
268 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
269 			return got_error_from_errno("asprintf");
270 	}
271 	*match = (strcmp(absprefix ? absprefix : path_prefix,
272 	    worktree->path_prefix) == 0);
273 	free(absprefix);
274 	return NULL;
275 }
276 
277 const char *
278 got_worktree_get_head_ref_name(struct got_worktree *worktree)
279 {
280 	return worktree->head_ref_name;
281 }
282 
283 const struct got_error *
284 got_worktree_set_head_ref(struct got_worktree *worktree,
285     struct got_reference *head_ref)
286 {
287 	const struct got_error *err = NULL;
288 	char *path_got = NULL, *head_ref_name = NULL;
289 
290 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
291 	    GOT_WORKTREE_GOT_DIR) == -1) {
292 		err = got_error_from_errno("asprintf");
293 		path_got = NULL;
294 		goto done;
295 	}
296 
297 	head_ref_name = strdup(got_ref_get_name(head_ref));
298 	if (head_ref_name == NULL) {
299 		err = got_error_from_errno("strdup");
300 		goto done;
301 	}
302 
303 	err = write_head_ref(path_got, head_ref);
304 	if (err)
305 		goto done;
306 
307 	free(worktree->head_ref_name);
308 	worktree->head_ref_name = head_ref_name;
309 done:
310 	free(path_got);
311 	if (err)
312 		free(head_ref_name);
313 	return err;
314 }
315 
316 struct got_object_id *
317 got_worktree_get_base_commit_id(struct got_worktree *worktree)
318 {
319 	return worktree->base_commit_id;
320 }
321 
322 const struct got_error *
323 got_worktree_set_base_commit_id(struct got_worktree *worktree,
324     struct got_repository *repo, struct got_object_id *commit_id)
325 {
326 	const struct got_error *err;
327 	struct got_object *obj = NULL;
328 	char *id_str = NULL;
329 	char *path_got = NULL;
330 
331 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
332 	    GOT_WORKTREE_GOT_DIR) == -1) {
333 		err = got_error_from_errno("asprintf");
334 		path_got = NULL;
335 		goto done;
336 	}
337 
338 	err = got_object_open(&obj, repo, commit_id);
339 	if (err)
340 		return err;
341 
342 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
343 		err = got_error(GOT_ERR_OBJ_TYPE);
344 		goto done;
345 	}
346 
347 	/* Record our base commit. */
348 	err = got_object_id_str(&id_str, commit_id);
349 	if (err)
350 		goto done;
351 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
352 	if (err)
353 		goto done;
354 
355 	free(worktree->base_commit_id);
356 	worktree->base_commit_id = got_object_id_dup(commit_id);
357 	if (worktree->base_commit_id == NULL) {
358 		err = got_error_from_errno("got_object_id_dup");
359 		goto done;
360 	}
361 done:
362 	if (obj)
363 		got_object_close(obj);
364 	free(id_str);
365 	free(path_got);
366 	return err;
367 }
368 
369 const struct got_gotconfig *
370 got_worktree_get_gotconfig(struct got_worktree *worktree)
371 {
372 	return worktree->gotconfig;
373 }
374 
375 static const struct got_error *
376 lock_worktree(struct got_worktree *worktree, int operation)
377 {
378 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
379 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
380 		    : got_error_from_errno2("flock",
381 		    got_worktree_get_root_path(worktree)));
382 	return NULL;
383 }
384 
385 static const struct got_error *
386 add_dir_on_disk(struct got_worktree *worktree, const char *path)
387 {
388 	const struct got_error *err = NULL;
389 	char *abspath;
390 
391 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
392 		return got_error_from_errno("asprintf");
393 
394 	err = got_path_mkdir(abspath);
395 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
396 		struct stat sb;
397 		err = NULL;
398 		if (lstat(abspath, &sb) == -1) {
399 			err = got_error_from_errno2("lstat", abspath);
400 		} else if (!S_ISDIR(sb.st_mode)) {
401 			/* TODO directory is obstructed; do something */
402 			err = got_error_path(abspath, GOT_ERR_FILE_OBSTRUCTED);
403 		}
404 	}
405 	free(abspath);
406 	return err;
407 }
408 
409 static const struct got_error *
410 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
411 {
412 	const struct got_error *err = NULL;
413 	uint8_t fbuf1[8192];
414 	uint8_t fbuf2[8192];
415 	size_t flen1 = 0, flen2 = 0;
416 
417 	*same = 1;
418 
419 	for (;;) {
420 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
421 		if (flen1 == 0 && ferror(f1)) {
422 			err = got_error_from_errno("fread");
423 			break;
424 		}
425 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
426 		if (flen2 == 0 && ferror(f2)) {
427 			err = got_error_from_errno("fread");
428 			break;
429 		}
430 		if (flen1 == 0) {
431 			if (flen2 != 0)
432 				*same = 0;
433 			break;
434 		} else if (flen2 == 0) {
435 			if (flen1 != 0)
436 				*same = 0;
437 			break;
438 		} else if (flen1 == flen2) {
439 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
440 				*same = 0;
441 				break;
442 			}
443 		} else {
444 			*same = 0;
445 			break;
446 		}
447 	}
448 
449 	return err;
450 }
451 
452 static const struct got_error *
453 check_files_equal(int *same, FILE *f1, FILE *f2)
454 {
455 	struct stat sb;
456 	size_t size1, size2;
457 
458 	*same = 1;
459 
460 	if (fstat(fileno(f1), &sb) != 0)
461 		return got_error_from_errno("fstat");
462 	size1 = sb.st_size;
463 
464 	if (fstat(fileno(f2), &sb) != 0)
465 		return got_error_from_errno("fstat");
466 	size2 = sb.st_size;
467 
468 	if (size1 != size2) {
469 		*same = 0;
470 		return NULL;
471 	}
472 
473 	if (fseek(f1, 0L, SEEK_SET) == -1)
474 		return got_ferror(f1, GOT_ERR_IO);
475 	if (fseek(f2, 0L, SEEK_SET) == -1)
476 		return got_ferror(f2, GOT_ERR_IO);
477 
478 	return check_file_contents_equal(same, f1, f2);
479 }
480 
481 static const struct got_error *
482 copy_file_to_fd(off_t *outsize, FILE *f, int outfd)
483 {
484 	uint8_t fbuf[65536];
485 	size_t flen;
486 	ssize_t outlen;
487 
488 	*outsize = 0;
489 
490 	if (fseek(f, 0L, SEEK_SET) == -1)
491 		return got_ferror(f, GOT_ERR_IO);
492 
493 	for (;;) {
494 		flen = fread(fbuf, 1, sizeof(fbuf), f);
495 		if (flen == 0) {
496 			if (ferror(f))
497 				return got_error_from_errno("fread");
498 			if (feof(f))
499 				break;
500 		}
501 		outlen = write(outfd, fbuf, flen);
502 		if (outlen == -1)
503 			return got_error_from_errno("write");
504 		if (outlen != flen)
505 			return got_error(GOT_ERR_IO);
506 		*outsize += outlen;
507 	}
508 
509 	return NULL;
510 }
511 
512 static const struct got_error *
513 merge_binary_file(int *overlapcnt, int merged_fd,
514     FILE *f_deriv, FILE *f_orig, FILE *f_deriv2,
515     const char *label_deriv, const char *label_orig, const char *label_deriv2,
516     const char *ondisk_path)
517 {
518 	const struct got_error *err = NULL;
519 	int same_content, changed_deriv, changed_deriv2;
520 	int fd_orig = -1, fd_deriv = -1, fd_deriv2 = -1;
521 	off_t size_orig = 0, size_deriv = 0, size_deriv2 = 0;
522 	char *path_orig = NULL, *path_deriv = NULL, *path_deriv2 = NULL;
523 	char *base_path_orig = NULL, *base_path_deriv = NULL;
524 	char *base_path_deriv2 = NULL;
525 
526 	*overlapcnt = 0;
527 
528 	err = check_files_equal(&same_content, f_deriv, f_deriv2);
529 	if (err)
530 		return err;
531 
532 	if (same_content)
533 		return copy_file_to_fd(&size_deriv, f_deriv, merged_fd);
534 
535 	err = check_files_equal(&same_content, f_deriv, f_orig);
536 	if (err)
537 		return err;
538 	changed_deriv = !same_content;
539 	err = check_files_equal(&same_content, f_deriv2, f_orig);
540 	if (err)
541 		return err;
542 	changed_deriv2 = !same_content;
543 
544 	if (changed_deriv && changed_deriv2) {
545 		*overlapcnt = 1;
546 		if (asprintf(&base_path_orig, "%s-orig", ondisk_path) == -1) {
547 			err = got_error_from_errno("asprintf");
548 			goto done;
549 		}
550 		if (asprintf(&base_path_deriv, "%s-1", ondisk_path) == -1) {
551 			err = got_error_from_errno("asprintf");
552 			goto done;
553 		}
554 		if (asprintf(&base_path_deriv2, "%s-2", ondisk_path) == -1) {
555 			err = got_error_from_errno("asprintf");
556 			goto done;
557 		}
558 		err = got_opentemp_named_fd(&path_orig, &fd_orig,
559 		    base_path_orig, "");
560 		if (err)
561 			goto done;
562 		err = got_opentemp_named_fd(&path_deriv, &fd_deriv,
563 		    base_path_deriv, "");
564 		if (err)
565 			goto done;
566 		err = got_opentemp_named_fd(&path_deriv2, &fd_deriv2,
567 		    base_path_deriv2, "");
568 		if (err)
569 			goto done;
570 		err = copy_file_to_fd(&size_orig, f_orig, fd_orig);
571 		if (err)
572 			goto done;
573 		err = copy_file_to_fd(&size_deriv, f_deriv, fd_deriv);
574 		if (err)
575 			goto done;
576 		err = copy_file_to_fd(&size_deriv2, f_deriv2, fd_deriv2);
577 		if (err)
578 			goto done;
579 		if (dprintf(merged_fd, "Binary files differ and cannot be "
580 		    "merged automatically:\n") < 0) {
581 			err = got_error_from_errno("dprintf");
582 			goto done;
583 		}
584 		if (dprintf(merged_fd, "%s%s%s\nfile %s\n",
585 		    GOT_DIFF_CONFLICT_MARKER_BEGIN,
586 		    label_deriv ? " " : "",
587 		    label_deriv ? label_deriv : "",
588 		    path_deriv) < 0) {
589 			err = got_error_from_errno("dprintf");
590 			goto done;
591 		}
592 		if (size_orig > 0) {
593 			if (dprintf(merged_fd, "%s%s%s\nfile %s\n",
594 			    GOT_DIFF_CONFLICT_MARKER_ORIG,
595 			    label_orig ? " " : "",
596 			    label_orig ? label_orig : "",
597 			    path_orig) < 0) {
598 				err = got_error_from_errno("dprintf");
599 				goto done;
600 			}
601 		}
602 		if (dprintf(merged_fd, "%s\nfile %s\n%s%s%s\n",
603 		    GOT_DIFF_CONFLICT_MARKER_SEP,
604 		    path_deriv2,
605 		    GOT_DIFF_CONFLICT_MARKER_END,
606 		    label_deriv2 ?  " " : "",
607 		    label_deriv2 ? label_deriv2 : "") < 0) {
608 			err = got_error_from_errno("dprintf");
609 			goto done;
610 		}
611 	} else if (changed_deriv)
612 		err = copy_file_to_fd(&size_deriv, f_deriv, merged_fd);
613 	else if (changed_deriv2)
614 		err = copy_file_to_fd(&size_deriv2, f_deriv2, merged_fd);
615 done:
616 	if (size_orig == 0 && path_orig && unlink(path_orig) == -1 &&
617 	    err == NULL)
618 		err = got_error_from_errno2("unlink", path_orig);
619 	if (fd_orig != -1 && close(fd_orig) == -1 && err == NULL)
620 		err = got_error_from_errno2("close", path_orig);
621 	if (fd_deriv != -1 && close(fd_deriv) == -1 && err == NULL)
622 		err = got_error_from_errno2("close", path_deriv);
623 	if (fd_deriv2 != -1 && close(fd_deriv2) == -1 && err == NULL)
624 		err = got_error_from_errno2("close", path_deriv2);
625 	free(path_orig);
626 	free(path_deriv);
627 	free(path_deriv2);
628 	free(base_path_orig);
629 	free(base_path_deriv);
630 	free(base_path_deriv2);
631 	return err;
632 }
633 
634 /*
635  * Perform a 3-way merge where the file f_orig acts as the common
636  * ancestor, the file f_deriv acts as the first derived version,
637  * and the file f_deriv2 acts as the second derived version.
638  * The merge result will be written to a new file at ondisk_path; any
639  * existing file at this path will be replaced.
640  */
641 static const struct got_error *
642 merge_file(int *local_changes_subsumed, struct got_worktree *worktree,
643     FILE *f_orig, FILE *f_deriv, FILE *f_deriv2, const char *ondisk_path,
644     const char *path, uint16_t st_mode,
645     const char *label_orig, const char *label_deriv, const char *label_deriv2,
646     enum got_diff_algorithm diff_algo, struct got_repository *repo,
647     got_worktree_checkout_cb progress_cb, void *progress_arg)
648 {
649 	const struct got_error *err = NULL;
650 	int merged_fd = -1;
651 	FILE *f_merged = NULL;
652 	char *merged_path = NULL, *base_path = NULL;
653 	int overlapcnt = 0;
654 	char *parent = NULL;
655 
656 	*local_changes_subsumed = 0;
657 
658 	err = got_path_dirname(&parent, ondisk_path);
659 	if (err)
660 		return err;
661 
662 	if (asprintf(&base_path, "%s/got-merged", parent) == -1) {
663 		err = got_error_from_errno("asprintf");
664 		goto done;
665 	}
666 
667 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path, "");
668 	if (err)
669 		goto done;
670 
671 	err = got_merge_diff3(&overlapcnt, merged_fd, f_deriv, f_orig,
672 	    f_deriv2, label_deriv, label_orig, label_deriv2, diff_algo);
673 	if (err) {
674 		if (err->code != GOT_ERR_FILE_BINARY)
675 			goto done;
676 		err = merge_binary_file(&overlapcnt, merged_fd, f_deriv,
677 		    f_orig, f_deriv2, label_deriv, label_orig, label_deriv2,
678 		    ondisk_path);
679 		if (err)
680 			goto done;
681 	}
682 
683 	err = (*progress_cb)(progress_arg,
684 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
685 	if (err)
686 		goto done;
687 
688 	if (fsync(merged_fd) != 0) {
689 		err = got_error_from_errno("fsync");
690 		goto done;
691 	}
692 
693 	f_merged = fdopen(merged_fd, "r");
694 	if (f_merged == NULL) {
695 		err = got_error_from_errno("fdopen");
696 		goto done;
697 	}
698 	merged_fd = -1;
699 
700 	/* Check if a clean merge has subsumed all local changes. */
701 	if (overlapcnt == 0) {
702 		err = check_files_equal(local_changes_subsumed, f_deriv,
703 		    f_merged);
704 		if (err)
705 			goto done;
706 	}
707 
708 	if (fchmod(fileno(f_merged), apply_umask(st_mode)) != 0) {
709 		err = got_error_from_errno2("fchmod", merged_path);
710 		goto done;
711 	}
712 
713 	if (rename(merged_path, ondisk_path) != 0) {
714 		err = got_error_from_errno3("rename", merged_path,
715 		    ondisk_path);
716 		goto done;
717 	}
718 done:
719 	if (err) {
720 		if (merged_path)
721 			unlink(merged_path);
722 	}
723 	if (merged_fd != -1 && close(merged_fd) == -1 && err == NULL)
724 		err = got_error_from_errno("close");
725 	if (f_merged && fclose(f_merged) == EOF && err == NULL)
726 		err = got_error_from_errno("fclose");
727 	free(merged_path);
728 	free(base_path);
729 	free(parent);
730 	return err;
731 }
732 
733 static const struct got_error *
734 update_symlink(const char *ondisk_path, const char *target_path,
735     size_t target_len)
736 {
737 	/* This is not atomic but matches what 'ln -sf' does. */
738 	if (unlink(ondisk_path) == -1)
739 		return got_error_from_errno2("unlink", ondisk_path);
740 	if (symlink(target_path, ondisk_path) == -1)
741 		return got_error_from_errno3("symlink", target_path,
742 		    ondisk_path);
743 	return NULL;
744 }
745 
746 /*
747  * Overwrite a symlink (or a regular file in case there was a "bad" symlink)
748  * in the work tree with a file that contains conflict markers and the
749  * conflicting target paths of the original version, a "derived version"
750  * of a symlink from an incoming change, and a local version of the symlink.
751  *
752  * The original versions's target path can be NULL if it is not available,
753  * such as if both derived versions added a new symlink at the same path.
754  *
755  * The incoming derived symlink target is NULL in case the incoming change
756  * has deleted this symlink.
757  */
758 static const struct got_error *
759 install_symlink_conflict(const char *deriv_target,
760     struct got_object_id *deriv_base_commit_id, const char *orig_target,
761     const char *label_orig, const char *local_target, const char *ondisk_path)
762 {
763 	const struct got_error *err;
764 	char *id_str = NULL, *label_deriv = NULL, *path = NULL;
765 	FILE *f = NULL;
766 
767 	err = got_object_id_str(&id_str, deriv_base_commit_id);
768 	if (err)
769 		return got_error_from_errno("asprintf");
770 
771 	if (asprintf(&label_deriv, "%s: commit %s",
772 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
773 		err = got_error_from_errno("asprintf");
774 		goto done;
775 	}
776 
777 	err = got_opentemp_named(&path, &f, "got-symlink-conflict", "");
778 	if (err)
779 		goto done;
780 
781 	if (fchmod(fileno(f), apply_umask(GOT_DEFAULT_FILE_MODE)) == -1) {
782 		err = got_error_from_errno2("fchmod", path);
783 		goto done;
784 	}
785 
786 	if (fprintf(f, "%s %s\n%s\n%s%s%s%s%s\n%s\n%s\n",
787 	    GOT_DIFF_CONFLICT_MARKER_BEGIN, label_deriv,
788 	    deriv_target ? deriv_target : "(symlink was deleted)",
789 	    orig_target ? label_orig : "",
790 	    orig_target ? "\n" : "",
791 	    orig_target ? orig_target : "",
792 	    orig_target ? "\n" : "",
793 	    GOT_DIFF_CONFLICT_MARKER_SEP,
794 	    local_target, GOT_DIFF_CONFLICT_MARKER_END) < 0) {
795 		err = got_error_from_errno2("fprintf", path);
796 		goto done;
797 	}
798 
799 	if (unlink(ondisk_path) == -1) {
800 		err = got_error_from_errno2("unlink", ondisk_path);
801 		goto done;
802 	}
803 	if (rename(path, ondisk_path) == -1) {
804 		err = got_error_from_errno3("rename", path, ondisk_path);
805 		goto done;
806 	}
807 done:
808 	if (f != NULL && fclose(f) == EOF && err == NULL)
809 		err = got_error_from_errno2("fclose", path);
810 	free(path);
811 	free(id_str);
812 	free(label_deriv);
813 	return err;
814 }
815 
816 /* forward declaration */
817 static const struct got_error *
818 merge_blob(int *, struct got_worktree *, struct got_blob_object *,
819     const char *, const char *, uint16_t, const char *,
820     struct got_blob_object *, struct got_object_id *,
821     struct got_repository *, got_worktree_checkout_cb, void *);
822 
823 /*
824  * Merge a symlink into the work tree, where blob_orig acts as the common
825  * ancestor, deriv_target is the link target of the first derived version,
826  * and the symlink on disk acts as the second derived version.
827  * Assume that contents of both blobs represent symlinks.
828  */
829 static const struct got_error *
830 merge_symlink(struct got_worktree *worktree,
831     struct got_blob_object *blob_orig, const char *ondisk_path,
832     const char *path, const char *label_orig, const char *deriv_target,
833     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
834     got_worktree_checkout_cb progress_cb, void *progress_arg)
835 {
836 	const struct got_error *err = NULL;
837 	char *ancestor_target = NULL;
838 	struct stat sb;
839 	ssize_t ondisk_len, deriv_len;
840 	char ondisk_target[PATH_MAX];
841 	int have_local_change = 0;
842 	int have_incoming_change = 0;
843 
844 	if (lstat(ondisk_path, &sb) == -1)
845 		return got_error_from_errno2("lstat", ondisk_path);
846 
847 	ondisk_len = readlink(ondisk_path, ondisk_target,
848 	    sizeof(ondisk_target));
849 	if (ondisk_len == -1) {
850 		err = got_error_from_errno2("readlink",
851 		    ondisk_path);
852 		goto done;
853 	}
854 	ondisk_target[ondisk_len] = '\0';
855 
856 	if (blob_orig) {
857 		err = got_object_blob_read_to_str(&ancestor_target, blob_orig);
858 		if (err)
859 			goto done;
860 	}
861 
862 	if (ancestor_target == NULL ||
863 	    (ondisk_len != strlen(ancestor_target) ||
864 	    memcmp(ondisk_target, ancestor_target, ondisk_len) != 0))
865 		have_local_change = 1;
866 
867 	deriv_len = strlen(deriv_target);
868 	if (ancestor_target == NULL ||
869 	    (deriv_len != strlen(ancestor_target) ||
870 	    memcmp(deriv_target, ancestor_target, deriv_len) != 0))
871 		have_incoming_change = 1;
872 
873 	if (!have_local_change && !have_incoming_change) {
874 		if (ancestor_target) {
875 			/* Both sides made the same change. */
876 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
877 			    path);
878 		} else if (deriv_len == ondisk_len &&
879 		    memcmp(ondisk_target, deriv_target, deriv_len) == 0) {
880 			/* Both sides added the same symlink. */
881 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
882 			    path);
883 		} else {
884 			/* Both sides added symlinks which don't match. */
885 			err = install_symlink_conflict(deriv_target,
886 			    deriv_base_commit_id, ancestor_target,
887 			    label_orig, ondisk_target, ondisk_path);
888 			if (err)
889 				goto done;
890 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
891 			    path);
892 		}
893 	} else if (!have_local_change && have_incoming_change) {
894 		/* Apply the incoming change. */
895 		err = update_symlink(ondisk_path, deriv_target,
896 		    strlen(deriv_target));
897 		if (err)
898 			goto done;
899 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
900 	} else if (have_local_change && have_incoming_change) {
901 		if (deriv_len == ondisk_len &&
902 		    memcmp(deriv_target, ondisk_target, deriv_len) == 0) {
903 			/* Both sides made the same change. */
904 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
905 			    path);
906 		} else {
907 			err = install_symlink_conflict(deriv_target,
908 			    deriv_base_commit_id, ancestor_target, label_orig,
909 			    ondisk_target, ondisk_path);
910 			if (err)
911 				goto done;
912 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
913 			    path);
914 		}
915 	}
916 
917 done:
918 	free(ancestor_target);
919 	return err;
920 }
921 
922 static const struct got_error *
923 dump_symlink_target_path_to_file(FILE **outfile, const char *ondisk_path)
924 {
925 	const struct got_error *err = NULL;
926 	char target_path[PATH_MAX];
927 	ssize_t target_len;
928 	size_t n;
929 	FILE *f;
930 
931 	*outfile = NULL;
932 
933 	f = got_opentemp();
934 	if (f == NULL)
935 		return got_error_from_errno("got_opentemp");
936 	target_len = readlink(ondisk_path, target_path, sizeof(target_path));
937 	if (target_len == -1) {
938 		err = got_error_from_errno2("readlink", ondisk_path);
939 		goto done;
940 	}
941 	n = fwrite(target_path, 1, target_len, f);
942 	if (n != target_len) {
943 		err = got_ferror(f, GOT_ERR_IO);
944 		goto done;
945 	}
946 	if (fflush(f) == EOF) {
947 		err = got_error_from_errno("fflush");
948 		goto done;
949 	}
950 	if (fseek(f, 0L, SEEK_SET) == -1) {
951 		err = got_ferror(f, GOT_ERR_IO);
952 		goto done;
953 	}
954 done:
955 	if (err)
956 		fclose(f);
957 	else
958 		*outfile = f;
959 	return err;
960 }
961 
962 /*
963  * Perform a 3-way merge where blob_orig acts as the common ancestor,
964  * blob_deriv acts as the first derived version, and the file on disk
965  * acts as the second derived version.
966  */
967 static const struct got_error *
968 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
969     struct got_blob_object *blob_orig, const char *ondisk_path,
970     const char *path, uint16_t st_mode, const char *label_orig,
971     struct got_blob_object *blob_deriv,
972     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
973     got_worktree_checkout_cb progress_cb, void *progress_arg)
974 {
975 	const struct got_error *err = NULL;
976 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
977 	char *blob_orig_path = NULL;
978 	char *blob_deriv_path = NULL, *base_path = NULL, *id_str = NULL;
979 	char *label_deriv = NULL, *parent = NULL;
980 
981 	*local_changes_subsumed = 0;
982 
983 	err = got_path_dirname(&parent, ondisk_path);
984 	if (err)
985 		return err;
986 
987 	if (blob_orig) {
988 		if (asprintf(&base_path, "%s/got-merge-blob-orig",
989 		    parent) == -1) {
990 			err = got_error_from_errno("asprintf");
991 			base_path = NULL;
992 			goto done;
993 		}
994 
995 		err = got_opentemp_named(&blob_orig_path, &f_orig,
996 		    base_path, "");
997 		if (err)
998 			goto done;
999 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
1000 		    blob_orig);
1001 		if (err)
1002 			goto done;
1003 		free(base_path);
1004 	} else {
1005 		/*
1006 		 * No common ancestor exists. This is an "add vs add" conflict
1007 		 * and we simply use an empty ancestor file to make both files
1008 		 * appear in the merged result in their entirety.
1009 		 */
1010 		f_orig = got_opentemp();
1011 		if (f_orig == NULL) {
1012 			err = got_error_from_errno("got_opentemp");
1013 			goto done;
1014 		}
1015 	}
1016 
1017 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
1018 		err = got_error_from_errno("asprintf");
1019 		base_path = NULL;
1020 		goto done;
1021 	}
1022 
1023 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path, "");
1024 	if (err)
1025 		goto done;
1026 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
1027 	    blob_deriv);
1028 	if (err)
1029 		goto done;
1030 
1031 	err = got_object_id_str(&id_str, deriv_base_commit_id);
1032 	if (err)
1033 		goto done;
1034 	if (asprintf(&label_deriv, "%s: commit %s",
1035 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
1036 		err = got_error_from_errno("asprintf");
1037 		goto done;
1038 	}
1039 
1040 	/*
1041 	 * In order the run a 3-way merge with a symlink we copy the symlink's
1042 	 * target path into a temporary file and use that file with diff3.
1043 	 */
1044 	if (S_ISLNK(st_mode)) {
1045 		err = dump_symlink_target_path_to_file(&f_deriv2, ondisk_path);
1046 		if (err)
1047 			goto done;
1048 	} else {
1049 		int fd;
1050 		fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1051 		if (fd == -1) {
1052 			err = got_error_from_errno2("open", ondisk_path);
1053 			goto done;
1054 		}
1055 		f_deriv2 = fdopen(fd, "r");
1056 		if (f_deriv2 == NULL) {
1057 			err = got_error_from_errno2("fdopen", ondisk_path);
1058 			close(fd);
1059 			goto done;
1060 		}
1061 	}
1062 
1063 	err = merge_file(local_changes_subsumed, worktree, f_orig, f_deriv,
1064 	    f_deriv2, ondisk_path, path, st_mode, label_orig, label_deriv,
1065 	    NULL, GOT_DIFF_ALGORITHM_MYERS, repo, progress_cb, progress_arg);
1066 done:
1067 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
1068 		err = got_error_from_errno("fclose");
1069 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
1070 		err = got_error_from_errno("fclose");
1071 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
1072 		err = got_error_from_errno("fclose");
1073 	free(base_path);
1074 	if (blob_orig_path) {
1075 		unlink(blob_orig_path);
1076 		free(blob_orig_path);
1077 	}
1078 	if (blob_deriv_path) {
1079 		unlink(blob_deriv_path);
1080 		free(blob_deriv_path);
1081 	}
1082 	free(id_str);
1083 	free(label_deriv);
1084 	free(parent);
1085 	return err;
1086 }
1087 
1088 static const struct got_error *
1089 create_fileindex_entry(struct got_fileindex_entry **new_iep,
1090     struct got_fileindex *fileindex, struct got_object_id *base_commit_id,
1091     int wt_fd, const char *path, struct got_object_id *blob_id)
1092 {
1093 	const struct got_error *err = NULL;
1094 	struct got_fileindex_entry *new_ie;
1095 
1096 	*new_iep = NULL;
1097 
1098 	err = got_fileindex_entry_alloc(&new_ie, path);
1099 	if (err)
1100 		return err;
1101 
1102 	err = got_fileindex_entry_update(new_ie, wt_fd, path,
1103 	    blob_id->sha1, base_commit_id->sha1, 1);
1104 	if (err)
1105 		goto done;
1106 
1107 	err = got_fileindex_entry_add(fileindex, new_ie);
1108 done:
1109 	if (err)
1110 		got_fileindex_entry_free(new_ie);
1111 	else
1112 		*new_iep = new_ie;
1113 	return err;
1114 }
1115 
1116 static mode_t
1117 get_ondisk_perms(int executable, mode_t st_mode)
1118 {
1119 	mode_t xbits = S_IXUSR;
1120 
1121 	if (executable) {
1122 		/* Map read bits to execute bits. */
1123 		if (st_mode & S_IRGRP)
1124 			xbits |= S_IXGRP;
1125 		if (st_mode & S_IROTH)
1126 			xbits |= S_IXOTH;
1127 		return st_mode | xbits;
1128 	}
1129 
1130 	return st_mode;
1131 }
1132 
1133 static mode_t
1134 apply_umask(mode_t mode)
1135 {
1136 	mode_t um;
1137 
1138 	um = umask(000);
1139 	umask(um);
1140 	return mode & ~um;
1141 }
1142 
1143 /* forward declaration */
1144 static const struct got_error *
1145 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1146     const char *path, mode_t te_mode, mode_t st_mode,
1147     struct got_blob_object *blob, int restoring_missing_file,
1148     int reverting_versioned_file, int installing_bad_symlink,
1149     int path_is_unversioned, struct got_repository *repo,
1150     got_worktree_checkout_cb progress_cb, void *progress_arg);
1151 
1152 /*
1153  * This function assumes that the provided symlink target points at a
1154  * safe location in the work tree!
1155  */
1156 static const struct got_error *
1157 replace_existing_symlink(int *did_something, const char *ondisk_path,
1158     const char *target_path, size_t target_len)
1159 {
1160 	const struct got_error *err = NULL;
1161 	ssize_t elen;
1162 	char etarget[PATH_MAX];
1163 	int fd;
1164 
1165 	*did_something = 0;
1166 
1167 	/*
1168 	 * "Bad" symlinks (those pointing outside the work tree or into the
1169 	 * .got directory) are installed in the work tree as a regular file
1170 	 * which contains the bad symlink target path.
1171 	 * The new symlink target has already been checked for safety by our
1172 	 * caller. If we can successfully open a regular file then we simply
1173 	 * replace this file with a symlink below.
1174 	 */
1175 	fd = open(ondisk_path, O_RDWR | O_EXCL | O_NOFOLLOW | O_CLOEXEC);
1176 	if (fd == -1) {
1177 		if (!got_err_open_nofollow_on_symlink())
1178 			return got_error_from_errno2("open", ondisk_path);
1179 
1180 		/* We are updating an existing on-disk symlink. */
1181 		elen = readlink(ondisk_path, etarget, sizeof(etarget));
1182 		if (elen == -1)
1183 			return got_error_from_errno2("readlink", ondisk_path);
1184 
1185 		if (elen == target_len &&
1186 		    memcmp(etarget, target_path, target_len) == 0)
1187 			return NULL; /* nothing to do */
1188 	}
1189 
1190 	*did_something = 1;
1191 	err = update_symlink(ondisk_path, target_path, target_len);
1192 	if (fd != -1 && close(fd) == -1 && err == NULL)
1193 		err = got_error_from_errno2("close", ondisk_path);
1194 	return err;
1195 }
1196 
1197 static const struct got_error *
1198 is_bad_symlink_target(int *is_bad_symlink, const char *target_path,
1199     size_t target_len, const char *ondisk_path, const char *wtroot_path)
1200 {
1201 	const struct got_error *err = NULL;
1202 	char canonpath[PATH_MAX];
1203 	char *path_got = NULL;
1204 
1205 	*is_bad_symlink = 0;
1206 
1207 	if (target_len >= sizeof(canonpath)) {
1208 		*is_bad_symlink = 1;
1209 		return NULL;
1210 	}
1211 
1212 	/*
1213 	 * We do not use realpath(3) to resolve the symlink's target
1214 	 * path because we don't want to resolve symlinks recursively.
1215 	 * Instead we make the path absolute and then canonicalize it.
1216 	 * Relative symlink target lookup should begin at the directory
1217 	 * in which the blob object is being installed.
1218 	 */
1219 	if (!got_path_is_absolute(target_path)) {
1220 		char *abspath, *parent;
1221 		err = got_path_dirname(&parent, ondisk_path);
1222 		if (err)
1223 			return err;
1224 		if (asprintf(&abspath, "%s/%s",  parent, target_path) == -1) {
1225 			free(parent);
1226 			return got_error_from_errno("asprintf");
1227 		}
1228 		free(parent);
1229 		if (strlen(abspath) >= sizeof(canonpath)) {
1230 			err = got_error_path(abspath, GOT_ERR_BAD_PATH);
1231 			free(abspath);
1232 			return err;
1233 		}
1234 		err = got_canonpath(abspath, canonpath, sizeof(canonpath));
1235 		free(abspath);
1236 		if (err)
1237 			return err;
1238 	} else {
1239 		err = got_canonpath(target_path, canonpath, sizeof(canonpath));
1240 		if (err)
1241 			return err;
1242 	}
1243 
1244 	/* Only allow symlinks pointing at paths within the work tree. */
1245 	if (!got_path_is_child(canonpath, wtroot_path, strlen(wtroot_path))) {
1246 		*is_bad_symlink = 1;
1247 		return NULL;
1248 	}
1249 
1250 	/* Do not allow symlinks pointing into the .got directory. */
1251 	if (asprintf(&path_got, "%s/%s", wtroot_path,
1252 	    GOT_WORKTREE_GOT_DIR) == -1)
1253 		return got_error_from_errno("asprintf");
1254 	if (got_path_is_child(canonpath, path_got, strlen(path_got)))
1255 		*is_bad_symlink = 1;
1256 
1257 	free(path_got);
1258 	return NULL;
1259 }
1260 
1261 static const struct got_error *
1262 install_symlink(int *is_bad_symlink, struct got_worktree *worktree,
1263     const char *ondisk_path, const char *path, struct got_blob_object *blob,
1264     int restoring_missing_file, int reverting_versioned_file,
1265     int path_is_unversioned, int allow_bad_symlinks,
1266     struct got_repository *repo,
1267     got_worktree_checkout_cb progress_cb, void *progress_arg)
1268 {
1269 	const struct got_error *err = NULL;
1270 	char target_path[PATH_MAX];
1271 	size_t len, target_len = 0;
1272 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1273 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1274 
1275 	*is_bad_symlink = 0;
1276 
1277 	/*
1278 	 * Blob object content specifies the target path of the link.
1279 	 * If a symbolic link cannot be installed we instead create
1280 	 * a regular file which contains the link target path stored
1281 	 * in the blob object.
1282 	 */
1283 	do {
1284 		err = got_object_blob_read_block(&len, blob);
1285 		if (err)
1286 			return err;
1287 
1288 		if (len + target_len >= sizeof(target_path)) {
1289 			/* Path too long; install as a regular file. */
1290 			*is_bad_symlink = 1;
1291 			got_object_blob_rewind(blob);
1292 			return install_blob(worktree, ondisk_path, path,
1293 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1294 			    restoring_missing_file, reverting_versioned_file,
1295 			    1, path_is_unversioned, repo, progress_cb,
1296 			    progress_arg);
1297 		}
1298 		if (len > 0) {
1299 			/* Skip blob object header first time around. */
1300 			memcpy(target_path + target_len, buf + hdrlen,
1301 			    len - hdrlen);
1302 			target_len += len - hdrlen;
1303 			hdrlen = 0;
1304 		}
1305 	} while (len != 0);
1306 	target_path[target_len] = '\0';
1307 
1308 	err = is_bad_symlink_target(is_bad_symlink, target_path, target_len,
1309 	    ondisk_path, worktree->root_path);
1310 	if (err)
1311 		return err;
1312 
1313 	if (*is_bad_symlink && !allow_bad_symlinks) {
1314 		/* install as a regular file */
1315 		got_object_blob_rewind(blob);
1316 		err = install_blob(worktree, ondisk_path, path,
1317 		    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1318 		    restoring_missing_file, reverting_versioned_file, 1,
1319 		    path_is_unversioned, repo, progress_cb, progress_arg);
1320 		return err;
1321 	}
1322 
1323 	if (symlink(target_path, ondisk_path) == -1) {
1324 		if (errno == EEXIST) {
1325 			int symlink_replaced;
1326 			if (path_is_unversioned) {
1327 				err = (*progress_cb)(progress_arg,
1328 				    GOT_STATUS_UNVERSIONED, path);
1329 				return err;
1330 			}
1331 			err = replace_existing_symlink(&symlink_replaced,
1332 			    ondisk_path, target_path, target_len);
1333 			if (err)
1334 				return err;
1335 			if (progress_cb) {
1336 				if (symlink_replaced) {
1337 					err = (*progress_cb)(progress_arg,
1338 					    reverting_versioned_file ?
1339 					    GOT_STATUS_REVERT :
1340 					    GOT_STATUS_UPDATE, path);
1341 				} else {
1342 					err = (*progress_cb)(progress_arg,
1343 					    GOT_STATUS_EXISTS, path);
1344 				}
1345 			}
1346 			return err; /* Nothing else to do. */
1347 		}
1348 
1349 		if (errno == ENOENT) {
1350 			char *parent;
1351 			err = got_path_dirname(&parent, ondisk_path);
1352 			if (err)
1353 				return err;
1354 			err = add_dir_on_disk(worktree, parent);
1355 			free(parent);
1356 			if (err)
1357 				return err;
1358 			/*
1359 			 * Retry, and fall through to error handling
1360 			 * below if this second attempt fails.
1361 			 */
1362 			if (symlink(target_path, ondisk_path) != -1) {
1363 				err = NULL; /* success */
1364 				return err;
1365 			}
1366 		}
1367 
1368 		/* Handle errors from first or second creation attempt. */
1369 		if (errno == ENAMETOOLONG) {
1370 			/* bad target path; install as a regular file */
1371 			*is_bad_symlink = 1;
1372 			got_object_blob_rewind(blob);
1373 			err = install_blob(worktree, ondisk_path, path,
1374 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1375 			    restoring_missing_file, reverting_versioned_file, 1,
1376 			    path_is_unversioned, repo,
1377 			    progress_cb, progress_arg);
1378 		} else if (errno == ENOTDIR) {
1379 			err = got_error_path(ondisk_path,
1380 			    GOT_ERR_FILE_OBSTRUCTED);
1381 		} else {
1382 			err = got_error_from_errno3("symlink",
1383 			    target_path, ondisk_path);
1384 		}
1385 	} else if (progress_cb)
1386 		err = (*progress_cb)(progress_arg, reverting_versioned_file ?
1387 		    GOT_STATUS_REVERT : GOT_STATUS_ADD, path);
1388 	return err;
1389 }
1390 
1391 static const struct got_error *
1392 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1393     const char *path, mode_t te_mode, mode_t st_mode,
1394     struct got_blob_object *blob, int restoring_missing_file,
1395     int reverting_versioned_file, int installing_bad_symlink,
1396     int path_is_unversioned, struct got_repository *repo,
1397     got_worktree_checkout_cb progress_cb, void *progress_arg)
1398 {
1399 	const struct got_error *err = NULL;
1400 	int fd = -1;
1401 	size_t len, hdrlen;
1402 	int update = 0;
1403 	char *tmppath = NULL;
1404 	mode_t mode;
1405 
1406 	mode = get_ondisk_perms(te_mode & S_IXUSR, GOT_DEFAULT_FILE_MODE);
1407 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW |
1408 	    O_CLOEXEC, mode);
1409 	if (fd == -1) {
1410 		if (errno == ENOENT) {
1411 			char *parent;
1412 			err = got_path_dirname(&parent, path);
1413 			if (err)
1414 				return err;
1415 			err = add_dir_on_disk(worktree, parent);
1416 			free(parent);
1417 			if (err)
1418 				return err;
1419 			fd = open(ondisk_path,
1420 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW | O_CLOEXEC,
1421 			    mode);
1422 			if (fd == -1)
1423 				return got_error_from_errno2("open",
1424 				    ondisk_path);
1425 		} else if (errno == EEXIST) {
1426 			if (path_is_unversioned) {
1427 				err = (*progress_cb)(progress_arg,
1428 				    GOT_STATUS_UNVERSIONED, path);
1429 				goto done;
1430 			}
1431 			if (!(S_ISLNK(st_mode) && S_ISREG(te_mode)) &&
1432 			    !S_ISREG(st_mode) && !installing_bad_symlink) {
1433 				/* TODO file is obstructed; do something */
1434 				err = got_error_path(ondisk_path,
1435 				    GOT_ERR_FILE_OBSTRUCTED);
1436 				goto done;
1437 			} else {
1438 				err = got_opentemp_named_fd(&tmppath, &fd,
1439 				    ondisk_path, "");
1440 				if (err)
1441 					goto done;
1442 				update = 1;
1443 
1444 				if (fchmod(fd, apply_umask(mode)) == -1) {
1445 					err = got_error_from_errno2("fchmod",
1446 					    tmppath);
1447 					goto done;
1448 				}
1449 			}
1450 		} else
1451 			return got_error_from_errno2("open", ondisk_path);
1452 	}
1453 
1454 	if (progress_cb) {
1455 		if (restoring_missing_file)
1456 			err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING,
1457 			    path);
1458 		else if (reverting_versioned_file)
1459 			err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT,
1460 			    path);
1461 		else
1462 			err = (*progress_cb)(progress_arg,
1463 			    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
1464 		if (err)
1465 			goto done;
1466 	}
1467 
1468 	hdrlen = got_object_blob_get_hdrlen(blob);
1469 	do {
1470 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
1471 		err = got_object_blob_read_block(&len, blob);
1472 		if (err)
1473 			break;
1474 		if (len > 0) {
1475 			/* Skip blob object header first time around. */
1476 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
1477 			if (outlen == -1) {
1478 				err = got_error_from_errno("write");
1479 				goto done;
1480 			} else if (outlen != len - hdrlen) {
1481 				err = got_error(GOT_ERR_IO);
1482 				goto done;
1483 			}
1484 			hdrlen = 0;
1485 		}
1486 	} while (len != 0);
1487 
1488 	if (fsync(fd) != 0) {
1489 		err = got_error_from_errno("fsync");
1490 		goto done;
1491 	}
1492 
1493 	if (update) {
1494 		if (S_ISLNK(st_mode) && unlink(ondisk_path) == -1) {
1495 			err = got_error_from_errno2("unlink", ondisk_path);
1496 			goto done;
1497 		}
1498 		if (rename(tmppath, ondisk_path) != 0) {
1499 			err = got_error_from_errno3("rename", tmppath,
1500 			    ondisk_path);
1501 			goto done;
1502 		}
1503 		free(tmppath);
1504 		tmppath = NULL;
1505 	}
1506 
1507 done:
1508 	if (fd != -1 && close(fd) == -1 && err == NULL)
1509 		err = got_error_from_errno("close");
1510 	if (tmppath != NULL && unlink(tmppath) == -1 && err == NULL)
1511 		err = got_error_from_errno2("unlink", tmppath);
1512 	free(tmppath);
1513 	return err;
1514 }
1515 
1516 /*
1517  * Upgrade STATUS_MODIFY to STATUS_CONFLICT if a
1518  * conflict marker is found in newly added lines only.
1519  */
1520 static const struct got_error *
1521 get_modified_file_content_status(unsigned char *status,
1522     struct got_blob_object *blob, const char *path, struct stat *sb,
1523     FILE *ondisk_file)
1524 {
1525 	const struct got_error *err, *free_err;
1526 	const char *markers[3] = {
1527 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
1528 		GOT_DIFF_CONFLICT_MARKER_SEP,
1529 		GOT_DIFF_CONFLICT_MARKER_END
1530 	};
1531 	FILE *f1 = NULL;
1532 	struct got_diffreg_result *diffreg_result = NULL;
1533 	struct diff_result *r;
1534 	int nchunks_parsed, n, i = 0, ln = 0;
1535 	char *line = NULL;
1536 	size_t linesize = 0;
1537 	ssize_t linelen;
1538 
1539 	if (*status != GOT_STATUS_MODIFY)
1540 		return NULL;
1541 
1542 	f1 = got_opentemp();
1543 	if (f1 == NULL)
1544 		return got_error_from_errno("got_opentemp");
1545 
1546 	if (blob) {
1547 		got_object_blob_rewind(blob);
1548 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
1549 		if (err)
1550 			goto done;
1551 	}
1552 
1553 	err = got_diff_files(&diffreg_result, f1, 1, NULL, ondisk_file,
1554 	    1, NULL, 0, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
1555 	if (err)
1556 		goto done;
1557 
1558 	r = diffreg_result->result;
1559 
1560 	for (n = 0; n < r->chunks.len; n += nchunks_parsed) {
1561 		struct diff_chunk *c;
1562 		struct diff_chunk_context cc = {};
1563 		off_t pos;
1564 		int clc, crc;
1565 
1566 		/*
1567 		 * We can optimise a little by advancing straight
1568 		 * to the next chunk if this one has no added lines.
1569 		 */
1570 		c = diff_chunk_get(r, n);
1571 		clc = diff_chunk_get_left_count(c);
1572 		crc = diff_chunk_get_right_count(c);
1573 
1574 		if (!crc || crc == clc) {
1575 			nchunks_parsed = 1;
1576 			continue;  /* removed or unchanged lines */
1577 		}
1578 
1579 		pos = diff_chunk_get_right_start_pos(c);
1580 		if (fseek(ondisk_file, pos, SEEK_SET) == -1) {
1581 			err = got_ferror(ondisk_file, GOT_ERR_IO);
1582 			goto done;
1583 		}
1584 
1585 		diff_chunk_context_load_change(&cc, &nchunks_parsed, r, n, 0);
1586 		ln = cc.right.start;
1587 
1588 		while (ln < cc.right.end) {
1589 			linelen = getline(&line, &linesize, ondisk_file);
1590 			if (linelen == -1) {
1591 				if (feof(ondisk_file))
1592 					break;
1593 				err = got_ferror(ondisk_file, GOT_ERR_IO);
1594 				break;
1595 			}
1596 
1597 			if (line && strncmp(line, markers[i],
1598 			    strlen(markers[i])) == 0) {
1599 				if (strcmp(markers[i],
1600 				    GOT_DIFF_CONFLICT_MARKER_END) == 0) {
1601 					*status = GOT_STATUS_CONFLICT;
1602 					goto done;
1603 				} else
1604 					i++;
1605 			}
1606 			++ln;
1607 		}
1608 	}
1609 
1610 done:
1611 	free(line);
1612 	if (f1 != NULL && fclose(f1) == EOF && err == NULL)
1613 		err = got_error_from_errno("fclose");
1614 	free_err = got_diffreg_result_free(diffreg_result);
1615 	if (err == NULL)
1616 		err = free_err;
1617 
1618 	return err;
1619 }
1620 
1621 static int
1622 xbit_differs(struct got_fileindex_entry *ie, uint16_t st_mode)
1623 {
1624 	mode_t ie_mode = got_fileindex_perms_to_st(ie);
1625 	return ((ie_mode & S_IXUSR) != (st_mode & S_IXUSR));
1626 }
1627 
1628 static int
1629 stat_info_differs(struct got_fileindex_entry *ie, struct stat *sb)
1630 {
1631 	return !(ie->ctime_sec == sb->st_ctim.tv_sec &&
1632 	    ie->ctime_nsec == sb->st_ctim.tv_nsec &&
1633 	    ie->mtime_sec == sb->st_mtim.tv_sec &&
1634 	    ie->mtime_nsec == sb->st_mtim.tv_nsec &&
1635 	    ie->size == (sb->st_size & 0xffffffff) &&
1636 	    !xbit_differs(ie, sb->st_mode));
1637 }
1638 
1639 static unsigned char
1640 get_staged_status(struct got_fileindex_entry *ie)
1641 {
1642 	switch (got_fileindex_entry_stage_get(ie)) {
1643 	case GOT_FILEIDX_STAGE_ADD:
1644 		return GOT_STATUS_ADD;
1645 	case GOT_FILEIDX_STAGE_DELETE:
1646 		return GOT_STATUS_DELETE;
1647 	case GOT_FILEIDX_STAGE_MODIFY:
1648 		return GOT_STATUS_MODIFY;
1649 	default:
1650 		return GOT_STATUS_NO_CHANGE;
1651 	}
1652 }
1653 
1654 static const struct got_error *
1655 get_symlink_modification_status(unsigned char *status,
1656     struct got_fileindex_entry *ie, const char *abspath,
1657     int dirfd, const char *de_name, struct got_blob_object *blob)
1658 {
1659 	const struct got_error *err = NULL;
1660 	char target_path[PATH_MAX];
1661 	char etarget[PATH_MAX];
1662 	ssize_t elen;
1663 	size_t len, target_len = 0;
1664 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1665 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1666 
1667 	*status = GOT_STATUS_NO_CHANGE;
1668 
1669 	/* Blob object content specifies the target path of the link. */
1670 	do {
1671 		err = got_object_blob_read_block(&len, blob);
1672 		if (err)
1673 			return err;
1674 		if (len + target_len >= sizeof(target_path)) {
1675 			/*
1676 			 * Should not happen. The blob contents were OK
1677 			 * when this symlink was installed.
1678 			 */
1679 			return got_error(GOT_ERR_NO_SPACE);
1680 		}
1681 		if (len > 0) {
1682 			/* Skip blob object header first time around. */
1683 			memcpy(target_path + target_len, buf + hdrlen,
1684 			    len - hdrlen);
1685 			target_len += len - hdrlen;
1686 			hdrlen = 0;
1687 		}
1688 	} while (len != 0);
1689 	target_path[target_len] = '\0';
1690 
1691 	if (dirfd != -1) {
1692 		elen = readlinkat(dirfd, de_name, etarget, sizeof(etarget));
1693 		if (elen == -1)
1694 			return got_error_from_errno2("readlinkat", abspath);
1695 	} else {
1696 		elen = readlink(abspath, etarget, sizeof(etarget));
1697 		if (elen == -1)
1698 			return got_error_from_errno2("readlink", abspath);
1699 	}
1700 
1701 	if (elen != target_len || memcmp(etarget, target_path, target_len) != 0)
1702 		*status = GOT_STATUS_MODIFY;
1703 
1704 	return NULL;
1705 }
1706 
1707 static const struct got_error *
1708 get_file_status(unsigned char *status, struct stat *sb,
1709     struct got_fileindex_entry *ie, const char *abspath,
1710     int dirfd, const char *de_name, struct got_repository *repo)
1711 {
1712 	const struct got_error *err = NULL;
1713 	struct got_object_id id;
1714 	size_t hdrlen;
1715 	int fd = -1, fd1 = -1;
1716 	FILE *f = NULL;
1717 	uint8_t fbuf[8192];
1718 	struct got_blob_object *blob = NULL;
1719 	size_t flen, blen;
1720 	unsigned char staged_status;
1721 
1722 	staged_status = get_staged_status(ie);
1723 	*status = GOT_STATUS_NO_CHANGE;
1724 	memset(sb, 0, sizeof(*sb));
1725 
1726 	/*
1727 	 * Whenever the caller provides a directory descriptor and a
1728 	 * directory entry name for the file, use them! This prevents
1729 	 * race conditions if filesystem paths change beneath our feet.
1730 	 */
1731 	if (dirfd != -1) {
1732 		if (fstatat(dirfd, de_name, sb, AT_SYMLINK_NOFOLLOW) == -1) {
1733 			if (errno == ENOENT) {
1734 				if (got_fileindex_entry_has_file_on_disk(ie))
1735 					*status = GOT_STATUS_MISSING;
1736 				else
1737 					*status = GOT_STATUS_DELETE;
1738 				goto done;
1739 			}
1740 			err = got_error_from_errno2("fstatat", abspath);
1741 			goto done;
1742 		}
1743 	} else {
1744 		fd = open(abspath, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1745 		if (fd == -1 && errno != ENOENT &&
1746 		    !got_err_open_nofollow_on_symlink())
1747 			return got_error_from_errno2("open", abspath);
1748 		else if (fd == -1 && got_err_open_nofollow_on_symlink()) {
1749 			if (lstat(abspath, sb) == -1)
1750 				return got_error_from_errno2("lstat", abspath);
1751 		} else if (fd == -1 || fstat(fd, sb) == -1) {
1752 			if (errno == ENOENT) {
1753 				if (got_fileindex_entry_has_file_on_disk(ie))
1754 					*status = GOT_STATUS_MISSING;
1755 				else
1756 					*status = GOT_STATUS_DELETE;
1757 				goto done;
1758 			}
1759 			err = got_error_from_errno2("fstat", abspath);
1760 			goto done;
1761 		}
1762 	}
1763 
1764 	if (!S_ISREG(sb->st_mode) && !S_ISLNK(sb->st_mode)) {
1765 		*status = GOT_STATUS_OBSTRUCTED;
1766 		goto done;
1767 	}
1768 
1769 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1770 		*status = GOT_STATUS_DELETE;
1771 		goto done;
1772 	} else if (!got_fileindex_entry_has_blob(ie) &&
1773 	    staged_status != GOT_STATUS_ADD) {
1774 		*status = GOT_STATUS_ADD;
1775 		goto done;
1776 	}
1777 
1778 	if (!stat_info_differs(ie, sb))
1779 		goto done;
1780 
1781 	if (S_ISLNK(sb->st_mode) &&
1782 	    got_fileindex_entry_filetype_get(ie) != GOT_FILEIDX_MODE_SYMLINK) {
1783 		*status = GOT_STATUS_MODIFY;
1784 		goto done;
1785 	}
1786 
1787 	if (staged_status == GOT_STATUS_MODIFY ||
1788 	    staged_status == GOT_STATUS_ADD)
1789 		got_fileindex_entry_get_staged_blob_id(&id, ie);
1790 	else
1791 		got_fileindex_entry_get_blob_id(&id, ie);
1792 
1793 	fd1 = got_opentempfd();
1794 	if (fd1 == -1) {
1795 		err = got_error_from_errno("got_opentempfd");
1796 		goto done;
1797 	}
1798 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf), fd1);
1799 	if (err)
1800 		goto done;
1801 
1802 	if (S_ISLNK(sb->st_mode)) {
1803 		err = get_symlink_modification_status(status, ie,
1804 		    abspath, dirfd, de_name, blob);
1805 		goto done;
1806 	}
1807 
1808 	if (dirfd != -1) {
1809 		fd = openat(dirfd, de_name, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1810 		if (fd == -1) {
1811 			err = got_error_from_errno2("openat", abspath);
1812 			goto done;
1813 		}
1814 	}
1815 
1816 	f = fdopen(fd, "r");
1817 	if (f == NULL) {
1818 		err = got_error_from_errno2("fdopen", abspath);
1819 		goto done;
1820 	}
1821 	fd = -1;
1822 	hdrlen = got_object_blob_get_hdrlen(blob);
1823 	for (;;) {
1824 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1825 		err = got_object_blob_read_block(&blen, blob);
1826 		if (err)
1827 			goto done;
1828 		/* Skip length of blob object header first time around. */
1829 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1830 		if (flen == 0 && ferror(f)) {
1831 			err = got_error_from_errno("fread");
1832 			goto done;
1833 		}
1834 		if (blen - hdrlen == 0) {
1835 			if (flen != 0)
1836 				*status = GOT_STATUS_MODIFY;
1837 			break;
1838 		} else if (flen == 0) {
1839 			if (blen - hdrlen != 0)
1840 				*status = GOT_STATUS_MODIFY;
1841 			break;
1842 		} else if (blen - hdrlen == flen) {
1843 			/* Skip blob object header first time around. */
1844 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1845 				*status = GOT_STATUS_MODIFY;
1846 				break;
1847 			}
1848 		} else {
1849 			*status = GOT_STATUS_MODIFY;
1850 			break;
1851 		}
1852 		hdrlen = 0;
1853 	}
1854 
1855 	if (*status == GOT_STATUS_MODIFY) {
1856 		rewind(f);
1857 		err = get_modified_file_content_status(status, blob, ie->path,
1858 		    sb, f);
1859 	} else if (xbit_differs(ie, sb->st_mode))
1860 		*status = GOT_STATUS_MODE_CHANGE;
1861 done:
1862 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
1863 		err = got_error_from_errno("close");
1864 	if (blob)
1865 		got_object_blob_close(blob);
1866 	if (f != NULL && fclose(f) == EOF && err == NULL)
1867 		err = got_error_from_errno2("fclose", abspath);
1868 	if (fd != -1 && close(fd) == -1 && err == NULL)
1869 		err = got_error_from_errno2("close", abspath);
1870 	return err;
1871 }
1872 
1873 /*
1874  * Update timestamps in the file index if a file is unmodified and
1875  * we had to run a full content comparison to find out.
1876  */
1877 static const struct got_error *
1878 sync_timestamps(int wt_fd, const char *path, unsigned char status,
1879     struct got_fileindex_entry *ie, struct stat *sb)
1880 {
1881 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1882 		return got_fileindex_entry_update(ie, wt_fd, path,
1883 		    ie->blob_sha1, ie->commit_sha1, 1);
1884 
1885 	return NULL;
1886 }
1887 
1888 static const struct got_error *
1889 update_blob(struct got_worktree *worktree,
1890     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1891     struct got_tree_entry *te, const char *path,
1892     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1893     void *progress_arg)
1894 {
1895 	const struct got_error *err = NULL;
1896 	struct got_blob_object *blob = NULL;
1897 	char *ondisk_path = NULL;
1898 	unsigned char status = GOT_STATUS_NO_CHANGE;
1899 	struct stat sb;
1900 	int fd1 = -1, fd2 = -1;
1901 
1902 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1903 		return got_error_from_errno("asprintf");
1904 
1905 	if (ie) {
1906 		if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE) {
1907 			err = got_error_path(ie->path, GOT_ERR_FILE_STAGED);
1908 			goto done;
1909 		}
1910 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
1911 		    repo);
1912 		if (err)
1913 			goto done;
1914 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1915 			sb.st_mode = got_fileindex_perms_to_st(ie);
1916 	} else {
1917 		if (stat(ondisk_path, &sb) == -1) {
1918 			if (errno != ENOENT) {
1919 				err = got_error_from_errno2("stat",
1920 				    ondisk_path);
1921 				goto done;
1922 			}
1923 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
1924 			status = GOT_STATUS_UNVERSIONED;
1925 		} else {
1926 			if (S_ISREG(sb.st_mode) || S_ISLNK(sb.st_mode))
1927 				status = GOT_STATUS_UNVERSIONED;
1928 			else
1929 				status = GOT_STATUS_OBSTRUCTED;
1930 		}
1931 	}
1932 
1933 	if (status == GOT_STATUS_OBSTRUCTED) {
1934 		if (ie)
1935 			got_fileindex_entry_mark_skipped(ie);
1936 		err = (*progress_cb)(progress_arg, status, path);
1937 		goto done;
1938 	}
1939 	if (status == GOT_STATUS_CONFLICT) {
1940 		if (ie)
1941 			got_fileindex_entry_mark_skipped(ie);
1942 		err = (*progress_cb)(progress_arg, GOT_STATUS_CANNOT_UPDATE,
1943 		    path);
1944 		goto done;
1945 	}
1946 
1947 	if (ie && status != GOT_STATUS_MISSING && S_ISREG(sb.st_mode) &&
1948 	    (S_ISLNK(te->mode) ||
1949 	    (te->mode & S_IXUSR) == (sb.st_mode & S_IXUSR))) {
1950 		/*
1951 		 * This is a regular file or an installed bad symlink.
1952 		 * If the file index indicates that this file is already
1953 		 * up-to-date with respect to the repository we can skip
1954 		 * updating contents of this file.
1955 		 */
1956 		if (got_fileindex_entry_has_commit(ie) &&
1957 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1958 		    SHA1_DIGEST_LENGTH) == 0) {
1959 			/* Same commit. */
1960 			err = sync_timestamps(worktree->root_fd,
1961 			    path, status, ie, &sb);
1962 			if (err)
1963 				goto done;
1964 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1965 			    path);
1966 			goto done;
1967 		}
1968 		if (got_fileindex_entry_has_blob(ie) &&
1969 		    memcmp(ie->blob_sha1, te->id.sha1,
1970 		    SHA1_DIGEST_LENGTH) == 0) {
1971 			/* Different commit but the same blob. */
1972 			err = sync_timestamps(worktree->root_fd,
1973 			    path, status, ie, &sb);
1974 			if (err)
1975 				goto done;
1976 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1977 			    path);
1978 			goto done;
1979 		}
1980 	}
1981 
1982 	fd1 = got_opentempfd();
1983 	if (fd1 == -1) {
1984 		err = got_error_from_errno("got_opentempfd");
1985 		goto done;
1986 	}
1987 	err = got_object_open_as_blob(&blob, repo, &te->id, 8192, fd1);
1988 	if (err)
1989 		goto done;
1990 
1991 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1992 		int update_timestamps;
1993 		struct got_blob_object *blob2 = NULL;
1994 		char *label_orig = NULL;
1995 		if (got_fileindex_entry_has_blob(ie)) {
1996 			fd2 = got_opentempfd();
1997 			if (fd2 == -1) {
1998 				err = got_error_from_errno("got_opentempfd");
1999 				goto done;
2000 			}
2001 			struct got_object_id id2;
2002 			got_fileindex_entry_get_blob_id(&id2, ie);
2003 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192,
2004 			    fd2);
2005 			if (err)
2006 				goto done;
2007 		}
2008 		if (got_fileindex_entry_has_commit(ie)) {
2009 			char id_str[SHA1_DIGEST_STRING_LENGTH];
2010 			if (got_sha1_digest_to_str(ie->commit_sha1, id_str,
2011 			    sizeof(id_str)) == NULL) {
2012 				err = got_error_path(id_str,
2013 				    GOT_ERR_BAD_OBJ_ID_STR);
2014 				goto done;
2015 			}
2016 			if (asprintf(&label_orig, "%s: commit %s",
2017 			    GOT_MERGE_LABEL_BASE, id_str) == -1) {
2018 				err = got_error_from_errno("asprintf");
2019 				goto done;
2020 			}
2021 		}
2022 		if (S_ISLNK(te->mode) && S_ISLNK(sb.st_mode)) {
2023 			char *link_target;
2024 			err = got_object_blob_read_to_str(&link_target, blob);
2025 			if (err)
2026 				goto done;
2027 			err = merge_symlink(worktree, blob2, ondisk_path, path,
2028 			    label_orig, link_target, worktree->base_commit_id,
2029 			    repo, progress_cb, progress_arg);
2030 			free(link_target);
2031 		} else {
2032 			err = merge_blob(&update_timestamps, worktree, blob2,
2033 			    ondisk_path, path, sb.st_mode, label_orig, blob,
2034 			    worktree->base_commit_id, repo,
2035 			    progress_cb, progress_arg);
2036 		}
2037 		free(label_orig);
2038 		if (fd2 != -1 && close(fd2) == -1 && err == NULL) {
2039 			err = got_error_from_errno("close");
2040 			goto done;
2041 		}
2042 		if (blob2)
2043 			got_object_blob_close(blob2);
2044 		if (err)
2045 			goto done;
2046 		/*
2047 		 * Do not update timestamps of files with local changes.
2048 		 * Otherwise, a future status walk would treat them as
2049 		 * unmodified files again.
2050 		 */
2051 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
2052 		    blob->id.sha1, worktree->base_commit_id->sha1,
2053 		    update_timestamps);
2054 	} else if (status == GOT_STATUS_MODE_CHANGE) {
2055 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
2056 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
2057 	} else if (status == GOT_STATUS_DELETE) {
2058 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
2059 		if (err)
2060 			goto done;
2061 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
2062 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
2063 		if (err)
2064 			goto done;
2065 	} else {
2066 		int is_bad_symlink = 0;
2067 		if (S_ISLNK(te->mode)) {
2068 			err = install_symlink(&is_bad_symlink, worktree,
2069 			    ondisk_path, path, blob,
2070 			    status == GOT_STATUS_MISSING, 0,
2071 			    status == GOT_STATUS_UNVERSIONED, 0,
2072 			    repo, progress_cb, progress_arg);
2073 		} else {
2074 			err = install_blob(worktree, ondisk_path, path,
2075 			    te->mode, sb.st_mode, blob,
2076 			    status == GOT_STATUS_MISSING, 0, 0,
2077 			    status == GOT_STATUS_UNVERSIONED, repo,
2078 			    progress_cb, progress_arg);
2079 		}
2080 		if (err)
2081 			goto done;
2082 
2083 		if (ie) {
2084 			err = got_fileindex_entry_update(ie,
2085 			    worktree->root_fd, path, blob->id.sha1,
2086 			    worktree->base_commit_id->sha1, 1);
2087 		} else {
2088 			err = create_fileindex_entry(&ie, fileindex,
2089 			    worktree->base_commit_id, worktree->root_fd, path,
2090 			    &blob->id);
2091 		}
2092 		if (err)
2093 			goto done;
2094 
2095 		if (is_bad_symlink) {
2096 			got_fileindex_entry_filetype_set(ie,
2097 			    GOT_FILEIDX_MODE_BAD_SYMLINK);
2098 		}
2099 	}
2100 
2101 	if (fd1 != -1 && close(fd1) == -1 && err == NULL) {
2102 		err = got_error_from_errno("close");
2103 		goto done;
2104 	}
2105 	got_object_blob_close(blob);
2106 done:
2107 	free(ondisk_path);
2108 	return err;
2109 }
2110 
2111 static const struct got_error *
2112 remove_ondisk_file(const char *root_path, const char *path)
2113 {
2114 	const struct got_error *err = NULL;
2115 	char *ondisk_path = NULL, *parent = NULL;
2116 
2117 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
2118 		return got_error_from_errno("asprintf");
2119 
2120 	if (unlink(ondisk_path) == -1) {
2121 		if (errno != ENOENT)
2122 			err = got_error_from_errno2("unlink", ondisk_path);
2123 	} else {
2124 		size_t root_len = strlen(root_path);
2125 		err = got_path_dirname(&parent, ondisk_path);
2126 		if (err)
2127 			goto done;
2128 		while (got_path_cmp(parent, root_path,
2129 		    strlen(parent), root_len) != 0) {
2130 			free(ondisk_path);
2131 			ondisk_path = parent;
2132 			parent = NULL;
2133 			if (rmdir(ondisk_path) == -1) {
2134 				if (errno != ENOTEMPTY)
2135 					err = got_error_from_errno2("rmdir",
2136 					    ondisk_path);
2137 				break;
2138 			}
2139 			err = got_path_dirname(&parent, ondisk_path);
2140 			if (err)
2141 				break;
2142 		}
2143 	}
2144 done:
2145 	free(ondisk_path);
2146 	free(parent);
2147 	return err;
2148 }
2149 
2150 static const struct got_error *
2151 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
2152     struct got_fileindex_entry *ie, struct got_repository *repo,
2153     got_worktree_checkout_cb progress_cb, void *progress_arg)
2154 {
2155 	const struct got_error *err = NULL;
2156 	unsigned char status;
2157 	struct stat sb;
2158 	char *ondisk_path;
2159 
2160 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
2161 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
2162 
2163 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
2164 	    == -1)
2165 		return got_error_from_errno("asprintf");
2166 
2167 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, repo);
2168 	if (err)
2169 		goto done;
2170 
2171 	if (S_ISLNK(sb.st_mode) && status != GOT_STATUS_NO_CHANGE) {
2172 		char ondisk_target[PATH_MAX];
2173 		ssize_t ondisk_len = readlink(ondisk_path, ondisk_target,
2174 		    sizeof(ondisk_target));
2175 		if (ondisk_len == -1) {
2176 			err = got_error_from_errno2("readlink", ondisk_path);
2177 			goto done;
2178 		}
2179 		ondisk_target[ondisk_len] = '\0';
2180 		err = install_symlink_conflict(NULL, worktree->base_commit_id,
2181 		    NULL, NULL, /* XXX pass common ancestor info? */
2182 		    ondisk_target, ondisk_path);
2183 		if (err)
2184 			goto done;
2185 		err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
2186 		    ie->path);
2187 		goto done;
2188 	}
2189 
2190 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
2191 	    status == GOT_STATUS_ADD) {
2192 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
2193 		if (err)
2194 			goto done;
2195 		/*
2196 		 * Preserve the working file and change the deleted blob's
2197 		 * entry into a schedule-add entry.
2198 		 */
2199 		err = got_fileindex_entry_update(ie, worktree->root_fd,
2200 		    ie->path, NULL, NULL, 0);
2201 	} else {
2202 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
2203 		if (err)
2204 			goto done;
2205 		if (status == GOT_STATUS_NO_CHANGE) {
2206 			err = remove_ondisk_file(worktree->root_path, ie->path);
2207 			if (err)
2208 				goto done;
2209 		}
2210 		got_fileindex_entry_remove(fileindex, ie);
2211 	}
2212 done:
2213 	free(ondisk_path);
2214 	return err;
2215 }
2216 
2217 struct diff_cb_arg {
2218     struct got_fileindex *fileindex;
2219     struct got_worktree *worktree;
2220     struct got_repository *repo;
2221     got_worktree_checkout_cb progress_cb;
2222     void *progress_arg;
2223     got_cancel_cb cancel_cb;
2224     void *cancel_arg;
2225 };
2226 
2227 static const struct got_error *
2228 diff_old_new(void *arg, struct got_fileindex_entry *ie,
2229     struct got_tree_entry *te, const char *parent_path)
2230 {
2231 	struct diff_cb_arg *a = arg;
2232 
2233 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2234 		return got_error(GOT_ERR_CANCELLED);
2235 
2236 	return update_blob(a->worktree, a->fileindex, ie, te,
2237 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
2238 }
2239 
2240 static const struct got_error *
2241 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2242 {
2243 	struct diff_cb_arg *a = arg;
2244 
2245 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2246 		return got_error(GOT_ERR_CANCELLED);
2247 
2248 	return delete_blob(a->worktree, a->fileindex, ie,
2249 	    a->repo, a->progress_cb, a->progress_arg);
2250 }
2251 
2252 static const struct got_error *
2253 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
2254 {
2255 	struct diff_cb_arg *a = arg;
2256 	const struct got_error *err;
2257 	char *path;
2258 
2259 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2260 		return got_error(GOT_ERR_CANCELLED);
2261 
2262 	if (got_object_tree_entry_is_submodule(te))
2263 		return NULL;
2264 
2265 	if (asprintf(&path, "%s%s%s", parent_path,
2266 	    parent_path[0] ? "/" : "", te->name)
2267 	    == -1)
2268 		return got_error_from_errno("asprintf");
2269 
2270 	if (S_ISDIR(te->mode))
2271 		err = add_dir_on_disk(a->worktree, path);
2272 	else
2273 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
2274 		    a->repo, a->progress_cb, a->progress_arg);
2275 
2276 	free(path);
2277 	return err;
2278 }
2279 
2280 const struct got_error *
2281 got_worktree_get_uuid(char **uuidstr, struct got_worktree *worktree)
2282 {
2283 	uint32_t uuid_status;
2284 
2285 	uuid_to_string(&worktree->uuid, uuidstr, &uuid_status);
2286 	if (uuid_status != uuid_s_ok) {
2287 		*uuidstr = NULL;
2288 		return got_error_uuid(uuid_status, "uuid_to_string");
2289 	}
2290 
2291 	return NULL;
2292 }
2293 
2294 static const struct got_error *
2295 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
2296 {
2297 	const struct got_error *err = NULL;
2298 	char *uuidstr = NULL;
2299 
2300 	*refname = NULL;
2301 
2302 	err = got_worktree_get_uuid(&uuidstr, worktree);
2303 	if (err)
2304 		return err;
2305 
2306 	if (asprintf(refname, "%s-%s", prefix, uuidstr) == -1) {
2307 		err = got_error_from_errno("asprintf");
2308 		*refname = NULL;
2309 	}
2310 	free(uuidstr);
2311 	return err;
2312 }
2313 
2314 const struct got_error *
2315 got_worktree_get_logmsg_ref_name(char **refname, struct got_worktree *worktree,
2316     const char *prefix)
2317 {
2318 	return get_ref_name(refname, worktree, prefix);
2319 }
2320 
2321 const struct got_error *
2322 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
2323 {
2324 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
2325 }
2326 
2327 static const struct got_error *
2328 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
2329 {
2330 	return get_ref_name(refname, worktree,
2331 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
2332 }
2333 
2334 static const struct got_error *
2335 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
2336 {
2337 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
2338 }
2339 
2340 static const struct got_error *
2341 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
2342 {
2343 	return get_ref_name(refname, worktree,
2344 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
2345 }
2346 
2347 static const struct got_error *
2348 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
2349 {
2350 	return get_ref_name(refname, worktree,
2351 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
2352 }
2353 
2354 static const struct got_error *
2355 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
2356 {
2357 	return get_ref_name(refname, worktree,
2358 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
2359 }
2360 
2361 static const struct got_error *
2362 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
2363 {
2364 	return get_ref_name(refname, worktree,
2365 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
2366 }
2367 
2368 static const struct got_error *
2369 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
2370 {
2371 	return get_ref_name(refname, worktree,
2372 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
2373 }
2374 
2375 static const struct got_error *
2376 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
2377 {
2378 	return get_ref_name(refname, worktree,
2379 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
2380 }
2381 
2382 const struct got_error *
2383 got_worktree_get_histedit_script_path(char **path,
2384     struct got_worktree *worktree)
2385 {
2386 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
2387 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
2388 		*path = NULL;
2389 		return got_error_from_errno("asprintf");
2390 	}
2391 	return NULL;
2392 }
2393 
2394 static const struct got_error *
2395 get_merge_branch_ref_name(char **refname, struct got_worktree *worktree)
2396 {
2397 	return get_ref_name(refname, worktree,
2398 	    GOT_WORKTREE_MERGE_BRANCH_REF_PREFIX);
2399 }
2400 
2401 static const struct got_error *
2402 get_merge_commit_ref_name(char **refname, struct got_worktree *worktree)
2403 {
2404 	return get_ref_name(refname, worktree,
2405 	    GOT_WORKTREE_MERGE_COMMIT_REF_PREFIX);
2406 }
2407 
2408 /*
2409  * Prevent Git's garbage collector from deleting our base commit by
2410  * setting a reference to our base commit's ID.
2411  */
2412 static const struct got_error *
2413 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
2414 {
2415 	const struct got_error *err = NULL;
2416 	struct got_reference *ref = NULL;
2417 	char *refname;
2418 
2419 	err = got_worktree_get_base_ref_name(&refname, worktree);
2420 	if (err)
2421 		return err;
2422 
2423 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
2424 	if (err)
2425 		goto done;
2426 
2427 	err = got_ref_write(ref, repo);
2428 done:
2429 	free(refname);
2430 	if (ref)
2431 		got_ref_close(ref);
2432 	return err;
2433 }
2434 
2435 static const struct got_error *
2436 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
2437 {
2438 	const struct got_error *err = NULL;
2439 
2440 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
2441 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2442 		err = got_error_from_errno("asprintf");
2443 		*fileindex_path = NULL;
2444 	}
2445 	return err;
2446 }
2447 
2448 
2449 static const struct got_error *
2450 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
2451     struct got_worktree *worktree)
2452 {
2453 	const struct got_error *err = NULL;
2454 	FILE *index = NULL;
2455 
2456 	*fileindex_path = NULL;
2457 	*fileindex = got_fileindex_alloc();
2458 	if (*fileindex == NULL)
2459 		return got_error_from_errno("got_fileindex_alloc");
2460 
2461 	err = get_fileindex_path(fileindex_path, worktree);
2462 	if (err)
2463 		goto done;
2464 
2465 	index = fopen(*fileindex_path, "rbe");
2466 	if (index == NULL) {
2467 		if (errno != ENOENT)
2468 			err = got_error_from_errno2("fopen", *fileindex_path);
2469 	} else {
2470 		err = got_fileindex_read(*fileindex, index);
2471 		if (fclose(index) == EOF && err == NULL)
2472 			err = got_error_from_errno("fclose");
2473 	}
2474 done:
2475 	if (err) {
2476 		free(*fileindex_path);
2477 		*fileindex_path = NULL;
2478 		got_fileindex_free(*fileindex);
2479 		*fileindex = NULL;
2480 	}
2481 	return err;
2482 }
2483 
2484 struct bump_base_commit_id_arg {
2485 	struct got_object_id *base_commit_id;
2486 	const char *path;
2487 	size_t path_len;
2488 	const char *entry_name;
2489 	got_worktree_checkout_cb progress_cb;
2490 	void *progress_arg;
2491 };
2492 
2493 static const struct got_error *
2494 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
2495 {
2496 	const struct got_error *err;
2497 	struct bump_base_commit_id_arg *a = arg;
2498 
2499 	if (a->entry_name) {
2500 		if (strcmp(ie->path, a->path) != 0)
2501 			return NULL;
2502 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
2503 		return NULL;
2504 
2505 	if (got_fileindex_entry_was_skipped(ie))
2506 		return NULL;
2507 
2508 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
2509 	    SHA1_DIGEST_LENGTH) == 0)
2510 		return NULL;
2511 
2512 	if (a->progress_cb) {
2513 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
2514 		    ie->path);
2515 		if (err)
2516 			return err;
2517 	}
2518 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
2519 	return NULL;
2520 }
2521 
2522 /* Bump base commit ID of all files within an updated part of the work tree. */
2523 static const struct got_error *
2524 bump_base_commit_id_everywhere(struct got_worktree *worktree,
2525     struct got_fileindex *fileindex,
2526     got_worktree_checkout_cb progress_cb, void *progress_arg)
2527 {
2528 	struct bump_base_commit_id_arg bbc_arg;
2529 
2530 	bbc_arg.base_commit_id = worktree->base_commit_id;
2531 	bbc_arg.entry_name = NULL;
2532 	bbc_arg.path = "";
2533 	bbc_arg.path_len = 0;
2534 	bbc_arg.progress_cb = progress_cb;
2535 	bbc_arg.progress_arg = progress_arg;
2536 
2537 	return got_fileindex_for_each_entry_safe(fileindex,
2538 	    bump_base_commit_id, &bbc_arg);
2539 }
2540 
2541 static const struct got_error *
2542 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
2543 {
2544 	const struct got_error *err = NULL;
2545 	char *new_fileindex_path = NULL;
2546 	FILE *new_index = NULL;
2547 	struct timespec timeout;
2548 
2549 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2550 	    fileindex_path, "");
2551 	if (err)
2552 		goto done;
2553 
2554 	err = got_fileindex_write(fileindex, new_index);
2555 	if (err)
2556 		goto done;
2557 
2558 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2559 		err = got_error_from_errno3("rename", new_fileindex_path,
2560 		    fileindex_path);
2561 		unlink(new_fileindex_path);
2562 	}
2563 
2564 	/*
2565 	 * Sleep for a short amount of time to ensure that files modified after
2566 	 * this program exits have a different time stamp from the one which
2567 	 * was recorded in the file index.
2568 	 */
2569 	timeout.tv_sec = 0;
2570 	timeout.tv_nsec = 1;
2571 	nanosleep(&timeout,  NULL);
2572 done:
2573 	if (new_index)
2574 		fclose(new_index);
2575 	free(new_fileindex_path);
2576 	return err;
2577 }
2578 
2579 static const struct got_error *
2580 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
2581     struct got_object_id **tree_id, const char *wt_relpath,
2582     struct got_commit_object *base_commit, struct got_worktree *worktree,
2583     struct got_repository *repo)
2584 {
2585 	const struct got_error *err = NULL;
2586 	struct got_object_id *id = NULL;
2587 	char *in_repo_path = NULL;
2588 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
2589 
2590 	*entry_type = GOT_OBJ_TYPE_ANY;
2591 	*tree_relpath = NULL;
2592 	*tree_id = NULL;
2593 
2594 	if (wt_relpath[0] == '\0') {
2595 		/* Check out all files within the work tree. */
2596 		*entry_type = GOT_OBJ_TYPE_TREE;
2597 		*tree_relpath = strdup("");
2598 		if (*tree_relpath == NULL) {
2599 			err = got_error_from_errno("strdup");
2600 			goto done;
2601 		}
2602 		err = got_object_id_by_path(tree_id, repo, base_commit,
2603 		    worktree->path_prefix);
2604 		if (err)
2605 			goto done;
2606 		return NULL;
2607 	}
2608 
2609 	/* Check out a subset of files in the work tree. */
2610 
2611 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
2612 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
2613 		err = got_error_from_errno("asprintf");
2614 		goto done;
2615 	}
2616 
2617 	err = got_object_id_by_path(&id, repo, base_commit, in_repo_path);
2618 	if (err)
2619 		goto done;
2620 
2621 	free(in_repo_path);
2622 	in_repo_path = NULL;
2623 
2624 	err = got_object_get_type(entry_type, repo, id);
2625 	if (err)
2626 		goto done;
2627 
2628 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
2629 		/* Check out a single file. */
2630 		if (strchr(wt_relpath, '/')  == NULL) {
2631 			/* Check out a single file in work tree's root dir. */
2632 			in_repo_path = strdup(worktree->path_prefix);
2633 			if (in_repo_path == NULL) {
2634 				err = got_error_from_errno("strdup");
2635 				goto done;
2636 			}
2637 			*tree_relpath = strdup("");
2638 			if (*tree_relpath == NULL) {
2639 				err = got_error_from_errno("strdup");
2640 				goto done;
2641 			}
2642 		} else {
2643 			/* Check out a single file in a subdirectory. */
2644 			err = got_path_dirname(tree_relpath, wt_relpath);
2645 			if (err)
2646 				return err;
2647 			if (asprintf(&in_repo_path, "%s%s%s",
2648 			    worktree->path_prefix, is_root_wt ? "" : "/",
2649 			    *tree_relpath) == -1) {
2650 				err = got_error_from_errno("asprintf");
2651 				goto done;
2652 			}
2653 		}
2654 		err = got_object_id_by_path(tree_id, repo,
2655 		    base_commit, in_repo_path);
2656 	} else {
2657 		/* Check out all files within a subdirectory. */
2658 		*tree_id = got_object_id_dup(id);
2659 		if (*tree_id == NULL) {
2660 			err = got_error_from_errno("got_object_id_dup");
2661 			goto done;
2662 		}
2663 		*tree_relpath = strdup(wt_relpath);
2664 		if (*tree_relpath == NULL) {
2665 			err = got_error_from_errno("strdup");
2666 			goto done;
2667 		}
2668 	}
2669 done:
2670 	free(id);
2671 	free(in_repo_path);
2672 	if (err) {
2673 		*entry_type = GOT_OBJ_TYPE_ANY;
2674 		free(*tree_relpath);
2675 		*tree_relpath = NULL;
2676 		free(*tree_id);
2677 		*tree_id = NULL;
2678 	}
2679 	return err;
2680 }
2681 
2682 static const struct got_error *
2683 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2684     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
2685     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2686     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
2687 {
2688 	const struct got_error *err = NULL;
2689 	struct got_commit_object *commit = NULL;
2690 	struct got_tree_object *tree = NULL;
2691 	struct got_fileindex_diff_tree_cb diff_cb;
2692 	struct diff_cb_arg arg;
2693 
2694 	err = ref_base_commit(worktree, repo);
2695 	if (err) {
2696 		if (!(err->code == GOT_ERR_ERRNO &&
2697 		    (errno == EACCES || errno == EROFS)))
2698 			goto done;
2699 		err = (*progress_cb)(progress_arg,
2700 		    GOT_STATUS_BASE_REF_ERR, worktree->root_path);
2701 		if (err)
2702 			return err;
2703 	}
2704 
2705 	err = got_object_open_as_commit(&commit, repo,
2706 	    worktree->base_commit_id);
2707 	if (err)
2708 		goto done;
2709 
2710 	err = got_object_open_as_tree(&tree, repo, tree_id);
2711 	if (err)
2712 		goto done;
2713 
2714 	if (entry_name &&
2715 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
2716 		err = got_error_path(entry_name, GOT_ERR_NO_TREE_ENTRY);
2717 		goto done;
2718 	}
2719 
2720 	diff_cb.diff_old_new = diff_old_new;
2721 	diff_cb.diff_old = diff_old;
2722 	diff_cb.diff_new = diff_new;
2723 	arg.fileindex = fileindex;
2724 	arg.worktree = worktree;
2725 	arg.repo = repo;
2726 	arg.progress_cb = progress_cb;
2727 	arg.progress_arg = progress_arg;
2728 	arg.cancel_cb = cancel_cb;
2729 	arg.cancel_arg = cancel_arg;
2730 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
2731 	    entry_name, repo, &diff_cb, &arg);
2732 done:
2733 	if (tree)
2734 		got_object_tree_close(tree);
2735 	if (commit)
2736 		got_object_commit_close(commit);
2737 	return err;
2738 }
2739 
2740 const struct got_error *
2741 got_worktree_checkout_files(struct got_worktree *worktree,
2742     struct got_pathlist_head *paths, struct got_repository *repo,
2743     got_worktree_checkout_cb progress_cb, void *progress_arg,
2744     got_cancel_cb cancel_cb, void *cancel_arg)
2745 {
2746 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2747 	struct got_commit_object *commit = NULL;
2748 	struct got_tree_object *tree = NULL;
2749 	struct got_fileindex *fileindex = NULL;
2750 	char *fileindex_path = NULL;
2751 	struct got_pathlist_entry *pe;
2752 	struct tree_path_data {
2753 		STAILQ_ENTRY(tree_path_data) entry;
2754 		struct got_object_id *tree_id;
2755 		int entry_type;
2756 		char *relpath;
2757 		char *entry_name;
2758 	} *tpd = NULL;
2759 	STAILQ_HEAD(tree_paths, tree_path_data) tree_paths;
2760 
2761 	STAILQ_INIT(&tree_paths);
2762 
2763 	err = lock_worktree(worktree, LOCK_EX);
2764 	if (err)
2765 		return err;
2766 
2767 	err = got_object_open_as_commit(&commit, repo,
2768 	    worktree->base_commit_id);
2769 	if (err)
2770 		goto done;
2771 
2772 	/* Map all specified paths to in-repository trees. */
2773 	TAILQ_FOREACH(pe, paths, entry) {
2774 		tpd = malloc(sizeof(*tpd));
2775 		if (tpd == NULL) {
2776 			err = got_error_from_errno("malloc");
2777 			goto done;
2778 		}
2779 
2780 		err = find_tree_entry_for_checkout(&tpd->entry_type,
2781 		    &tpd->relpath, &tpd->tree_id, pe->path, commit,
2782 		    worktree, repo);
2783 		if (err) {
2784 			free(tpd);
2785 			goto done;
2786 		}
2787 
2788 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
2789 			err = got_path_basename(&tpd->entry_name, pe->path);
2790 			if (err) {
2791 				free(tpd->relpath);
2792 				free(tpd->tree_id);
2793 				free(tpd);
2794 				goto done;
2795 			}
2796 		} else
2797 			tpd->entry_name = NULL;
2798 
2799 		STAILQ_INSERT_TAIL(&tree_paths, tpd, entry);
2800 	}
2801 
2802 	/*
2803 	 * Read the file index.
2804 	 * Checking out files is supposed to be an idempotent operation.
2805 	 * If the on-disk file index is incomplete we will try to complete it.
2806 	 */
2807 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2808 	if (err)
2809 		goto done;
2810 
2811 	tpd = STAILQ_FIRST(&tree_paths);
2812 	TAILQ_FOREACH(pe, paths, entry) {
2813 		struct bump_base_commit_id_arg bbc_arg;
2814 
2815 		err = checkout_files(worktree, fileindex, tpd->relpath,
2816 		    tpd->tree_id, tpd->entry_name, repo,
2817 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
2818 		if (err)
2819 			break;
2820 
2821 		bbc_arg.base_commit_id = worktree->base_commit_id;
2822 		bbc_arg.entry_name = tpd->entry_name;
2823 		bbc_arg.path = pe->path;
2824 		bbc_arg.path_len = pe->path_len;
2825 		bbc_arg.progress_cb = progress_cb;
2826 		bbc_arg.progress_arg = progress_arg;
2827 		err = got_fileindex_for_each_entry_safe(fileindex,
2828 		    bump_base_commit_id, &bbc_arg);
2829 		if (err)
2830 			break;
2831 
2832 		tpd = STAILQ_NEXT(tpd, entry);
2833 	}
2834 	sync_err = sync_fileindex(fileindex, fileindex_path);
2835 	if (sync_err && err == NULL)
2836 		err = sync_err;
2837 done:
2838 	free(fileindex_path);
2839 	if (tree)
2840 		got_object_tree_close(tree);
2841 	if (commit)
2842 		got_object_commit_close(commit);
2843 	if (fileindex)
2844 		got_fileindex_free(fileindex);
2845 	while (!STAILQ_EMPTY(&tree_paths)) {
2846 		tpd = STAILQ_FIRST(&tree_paths);
2847 		STAILQ_REMOVE_HEAD(&tree_paths, entry);
2848 		free(tpd->relpath);
2849 		free(tpd->tree_id);
2850 		free(tpd);
2851 	}
2852 	unlockerr = lock_worktree(worktree, LOCK_SH);
2853 	if (unlockerr && err == NULL)
2854 		err = unlockerr;
2855 	return err;
2856 }
2857 
2858 struct merge_file_cb_arg {
2859     struct got_worktree *worktree;
2860     struct got_fileindex *fileindex;
2861     got_worktree_checkout_cb progress_cb;
2862     void *progress_arg;
2863     got_cancel_cb cancel_cb;
2864     void *cancel_arg;
2865     const char *label_orig;
2866     struct got_object_id *commit_id2;
2867     int allow_bad_symlinks;
2868 };
2869 
2870 static const struct got_error *
2871 merge_file_cb(void *arg, struct got_blob_object *blob1,
2872     struct got_blob_object *blob2, FILE *f1, FILE *f2,
2873     struct got_object_id *id1, struct got_object_id *id2,
2874     const char *path1, const char *path2,
2875     mode_t mode1, mode_t mode2, struct got_repository *repo)
2876 {
2877 	static const struct got_error *err = NULL;
2878 	struct merge_file_cb_arg *a = arg;
2879 	struct got_fileindex_entry *ie;
2880 	char *ondisk_path = NULL;
2881 	struct stat sb;
2882 	unsigned char status;
2883 	int local_changes_subsumed;
2884 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
2885 	char *id_str = NULL, *label_deriv2 = NULL;
2886 
2887 	if (blob1 && blob2) {
2888 		ie = got_fileindex_entry_get(a->fileindex, path2,
2889 		    strlen(path2));
2890 		if (ie == NULL)
2891 			return (*a->progress_cb)(a->progress_arg,
2892 			    GOT_STATUS_MISSING, path2);
2893 
2894 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2895 		    path2) == -1)
2896 			return got_error_from_errno("asprintf");
2897 
2898 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2899 		    repo);
2900 		if (err)
2901 			goto done;
2902 
2903 		if (status == GOT_STATUS_DELETE) {
2904 			err = (*a->progress_cb)(a->progress_arg,
2905 			    GOT_STATUS_MERGE, path2);
2906 			goto done;
2907 		}
2908 		if (status != GOT_STATUS_NO_CHANGE &&
2909 		    status != GOT_STATUS_MODIFY &&
2910 		    status != GOT_STATUS_CONFLICT &&
2911 		    status != GOT_STATUS_ADD) {
2912 			err = (*a->progress_cb)(a->progress_arg, status, path2);
2913 			goto done;
2914 		}
2915 
2916 		if (S_ISLNK(mode1) && S_ISLNK(mode2)) {
2917 			char *link_target2;
2918 			err = got_object_blob_read_to_str(&link_target2, blob2);
2919 			if (err)
2920 				goto done;
2921 			err = merge_symlink(a->worktree, blob1, ondisk_path,
2922 			    path2, a->label_orig, link_target2, a->commit_id2,
2923 			    repo, a->progress_cb, a->progress_arg);
2924 			free(link_target2);
2925 		} else {
2926 			int fd;
2927 
2928 			f_orig = got_opentemp();
2929 			if (f_orig == NULL) {
2930 				err = got_error_from_errno("got_opentemp");
2931 				goto done;
2932 			}
2933 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2934 			    f_orig, blob1);
2935 			if (err)
2936 				goto done;
2937 
2938 			f_deriv2 = got_opentemp();
2939 			if (f_deriv2 == NULL)
2940 				goto done;
2941 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2942 			    f_deriv2, blob2);
2943 			if (err)
2944 				goto done;
2945 
2946 			fd = open(ondisk_path,
2947 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
2948 			if (fd == -1) {
2949 				err = got_error_from_errno2("open",
2950 				    ondisk_path);
2951 				goto done;
2952 			}
2953 			f_deriv = fdopen(fd, "r");
2954 			if (f_deriv == NULL) {
2955 				err = got_error_from_errno2("fdopen",
2956 				    ondisk_path);
2957 				close(fd);
2958 				goto done;
2959 			}
2960 			err = got_object_id_str(&id_str, a->commit_id2);
2961 			if (err)
2962 				goto done;
2963 			if (asprintf(&label_deriv2, "%s: commit %s",
2964 			    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
2965 				err = got_error_from_errno("asprintf");
2966 				goto done;
2967 			}
2968 			err = merge_file(&local_changes_subsumed, a->worktree,
2969 			    f_orig, f_deriv, f_deriv2, ondisk_path, path2,
2970 			    mode2, a->label_orig, NULL, label_deriv2,
2971 			    GOT_DIFF_ALGORITHM_PATIENCE, repo,
2972 			    a->progress_cb, a->progress_arg);
2973 		}
2974 	} else if (blob1) {
2975 		ie = got_fileindex_entry_get(a->fileindex, path1,
2976 		    strlen(path1));
2977 		if (ie == NULL)
2978 			return (*a->progress_cb)(a->progress_arg,
2979 			    GOT_STATUS_MISSING, path1);
2980 
2981 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2982 		    path1) == -1)
2983 			return got_error_from_errno("asprintf");
2984 
2985 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2986 		    repo);
2987 		if (err)
2988 			goto done;
2989 
2990 		switch (status) {
2991 		case GOT_STATUS_NO_CHANGE:
2992 			err = (*a->progress_cb)(a->progress_arg,
2993 			    GOT_STATUS_DELETE, path1);
2994 			if (err)
2995 				goto done;
2996 			err = remove_ondisk_file(a->worktree->root_path, path1);
2997 			if (err)
2998 				goto done;
2999 			if (ie)
3000 				got_fileindex_entry_mark_deleted_from_disk(ie);
3001 			break;
3002 		case GOT_STATUS_DELETE:
3003 		case GOT_STATUS_MISSING:
3004 			err = (*a->progress_cb)(a->progress_arg,
3005 			    GOT_STATUS_DELETE, path1);
3006 			if (err)
3007 				goto done;
3008 			if (ie)
3009 				got_fileindex_entry_mark_deleted_from_disk(ie);
3010 			break;
3011 		case GOT_STATUS_ADD: {
3012 			struct got_object_id *id;
3013 			FILE *blob1_f;
3014 			off_t blob1_size;
3015 			/*
3016 			 * Delete the added file only if its content already
3017 			 * exists in the repository.
3018 			 */
3019 			err = got_object_blob_file_create(&id, &blob1_f,
3020 			    &blob1_size, path1);
3021 			if (err)
3022 				goto done;
3023 			if (got_object_id_cmp(id, id1) == 0) {
3024 				err = (*a->progress_cb)(a->progress_arg,
3025 				    GOT_STATUS_DELETE, path1);
3026 				if (err)
3027 					goto done;
3028 				err = remove_ondisk_file(a->worktree->root_path,
3029 				    path1);
3030 				if (err)
3031 					goto done;
3032 				if (ie)
3033 					got_fileindex_entry_remove(a->fileindex,
3034 					    ie);
3035 			} else {
3036 				err = (*a->progress_cb)(a->progress_arg,
3037 				    GOT_STATUS_CANNOT_DELETE, path1);
3038 			}
3039 			if (fclose(blob1_f) == EOF && err == NULL)
3040 				err = got_error_from_errno("fclose");
3041 			free(id);
3042 			if (err)
3043 				goto done;
3044 			break;
3045 		}
3046 		case GOT_STATUS_MODIFY:
3047 		case GOT_STATUS_CONFLICT:
3048 			err = (*a->progress_cb)(a->progress_arg,
3049 			    GOT_STATUS_CANNOT_DELETE, path1);
3050 			if (err)
3051 				goto done;
3052 			break;
3053 		case GOT_STATUS_OBSTRUCTED:
3054 			err = (*a->progress_cb)(a->progress_arg, status, path1);
3055 			if (err)
3056 				goto done;
3057 			break;
3058 		default:
3059 			break;
3060 		}
3061 	} else if (blob2) {
3062 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
3063 		    path2) == -1)
3064 			return got_error_from_errno("asprintf");
3065 		ie = got_fileindex_entry_get(a->fileindex, path2,
3066 		    strlen(path2));
3067 		if (ie) {
3068 			err = get_file_status(&status, &sb, ie, ondisk_path,
3069 			    -1, NULL, repo);
3070 			if (err)
3071 				goto done;
3072 			if (status != GOT_STATUS_NO_CHANGE &&
3073 			    status != GOT_STATUS_MODIFY &&
3074 			    status != GOT_STATUS_CONFLICT &&
3075 			    status != GOT_STATUS_ADD) {
3076 				err = (*a->progress_cb)(a->progress_arg,
3077 				    status, path2);
3078 				goto done;
3079 			}
3080 			if (S_ISLNK(mode2) && S_ISLNK(sb.st_mode)) {
3081 				char *link_target2;
3082 				err = got_object_blob_read_to_str(&link_target2,
3083 				    blob2);
3084 				if (err)
3085 					goto done;
3086 				err = merge_symlink(a->worktree, NULL,
3087 				    ondisk_path, path2, a->label_orig,
3088 				    link_target2, a->commit_id2, repo,
3089 				    a->progress_cb, a->progress_arg);
3090 				free(link_target2);
3091 			} else if (S_ISREG(sb.st_mode)) {
3092 				err = merge_blob(&local_changes_subsumed,
3093 				    a->worktree, NULL, ondisk_path, path2,
3094 				    sb.st_mode, a->label_orig, blob2,
3095 				    a->commit_id2, repo, a->progress_cb,
3096 				    a->progress_arg);
3097 			} else {
3098 				err = got_error_path(ondisk_path,
3099 				    GOT_ERR_FILE_OBSTRUCTED);
3100 			}
3101 			if (err)
3102 				goto done;
3103 			if (status == GOT_STATUS_DELETE) {
3104 				err = got_fileindex_entry_update(ie,
3105 				    a->worktree->root_fd, path2, blob2->id.sha1,
3106 				    a->worktree->base_commit_id->sha1, 0);
3107 				if (err)
3108 					goto done;
3109 			}
3110 		} else {
3111 			int is_bad_symlink = 0;
3112 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
3113 			if (S_ISLNK(mode2)) {
3114 				err = install_symlink(&is_bad_symlink,
3115 				    a->worktree, ondisk_path, path2, blob2, 0,
3116 				    0, 1, a->allow_bad_symlinks, repo,
3117 				    a->progress_cb, a->progress_arg);
3118 			} else {
3119 				err = install_blob(a->worktree, ondisk_path, path2,
3120 				    mode2, sb.st_mode, blob2, 0, 0, 0, 1, repo,
3121 				    a->progress_cb, a->progress_arg);
3122 			}
3123 			if (err)
3124 				goto done;
3125 			err = got_fileindex_entry_alloc(&ie, path2);
3126 			if (err)
3127 				goto done;
3128 			err = got_fileindex_entry_update(ie,
3129 			    a->worktree->root_fd, path2, NULL, NULL, 1);
3130 			if (err) {
3131 				got_fileindex_entry_free(ie);
3132 				goto done;
3133 			}
3134 			err = got_fileindex_entry_add(a->fileindex, ie);
3135 			if (err) {
3136 				got_fileindex_entry_free(ie);
3137 				goto done;
3138 			}
3139 			if (is_bad_symlink) {
3140 				got_fileindex_entry_filetype_set(ie,
3141 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
3142 			}
3143 		}
3144 	}
3145 done:
3146 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
3147 		err = got_error_from_errno("fclose");
3148 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
3149 		err = got_error_from_errno("fclose");
3150 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
3151 		err = got_error_from_errno("fclose");
3152 	free(id_str);
3153 	free(label_deriv2);
3154 	free(ondisk_path);
3155 	return err;
3156 }
3157 
3158 static const struct got_error *
3159 check_mixed_commits(void *arg, struct got_fileindex_entry *ie)
3160 {
3161 	struct got_worktree *worktree = arg;
3162 
3163 	/* Reject merges into a work tree with mixed base commits. */
3164 	if (got_fileindex_entry_has_commit(ie) &&
3165 	    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
3166 	    SHA1_DIGEST_LENGTH) != 0)
3167 		return got_error(GOT_ERR_MIXED_COMMITS);
3168 
3169 	return NULL;
3170 }
3171 
3172 struct check_merge_conflicts_arg {
3173 	struct got_worktree *worktree;
3174 	struct got_fileindex *fileindex;
3175 	struct got_repository *repo;
3176 };
3177 
3178 static const struct got_error *
3179 check_merge_conflicts(void *arg, struct got_blob_object *blob1,
3180     struct got_blob_object *blob2, FILE *f1, FILE *f2,
3181     struct got_object_id *id1, struct got_object_id *id2,
3182     const char *path1, const char *path2,
3183     mode_t mode1, mode_t mode2, struct got_repository *repo)
3184 {
3185 	const struct got_error *err = NULL;
3186 	struct check_merge_conflicts_arg *a = arg;
3187 	unsigned char status;
3188 	struct stat sb;
3189 	struct got_fileindex_entry *ie;
3190 	const char *path = path2 ? path2 : path1;
3191 	struct got_object_id *id = id2 ? id2 : id1;
3192 	char *ondisk_path;
3193 
3194 	if (id == NULL)
3195 		return NULL;
3196 
3197 	ie = got_fileindex_entry_get(a->fileindex, path, strlen(path));
3198 	if (ie == NULL)
3199 		return NULL;
3200 
3201 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
3202 	    == -1)
3203 		return got_error_from_errno("asprintf");
3204 
3205 	/* Reject merges into a work tree with conflicted files. */
3206 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
3207 	free(ondisk_path);
3208 	if (err)
3209 		return err;
3210 	if (status == GOT_STATUS_CONFLICT)
3211 		return got_error(GOT_ERR_CONFLICTS);
3212 
3213 	return NULL;
3214 }
3215 
3216 static const struct got_error *
3217 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
3218     const char *fileindex_path, struct got_object_id *commit_id1,
3219     struct got_object_id *commit_id2, struct got_repository *repo,
3220     got_worktree_checkout_cb progress_cb, void *progress_arg,
3221     got_cancel_cb cancel_cb, void *cancel_arg)
3222 {
3223 	const struct got_error *err = NULL, *sync_err;
3224 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
3225 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
3226 	struct got_commit_object *commit1 = NULL, *commit2 = NULL;
3227 	struct check_merge_conflicts_arg cmc_arg;
3228 	struct merge_file_cb_arg arg;
3229 	char *label_orig = NULL;
3230 	FILE *f1 = NULL, *f2 = NULL;
3231 	int fd1 = -1, fd2 = -1;
3232 
3233 	if (commit_id1) {
3234 		err = got_object_open_as_commit(&commit1, repo, commit_id1);
3235 		if (err)
3236 			goto done;
3237 		err = got_object_id_by_path(&tree_id1, repo, commit1,
3238 		    worktree->path_prefix);
3239 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3240 			goto done;
3241 	}
3242 	if (tree_id1) {
3243 		char *id_str;
3244 
3245 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
3246 		if (err)
3247 			goto done;
3248 
3249 		err = got_object_id_str(&id_str, commit_id1);
3250 		if (err)
3251 			goto done;
3252 
3253 		if (asprintf(&label_orig, "%s: commit %s",
3254 		    GOT_MERGE_LABEL_BASE, id_str) == -1) {
3255 			err = got_error_from_errno("asprintf");
3256 			free(id_str);
3257 			goto done;
3258 		}
3259 		free(id_str);
3260 
3261 		f1 = got_opentemp();
3262 		if (f1 == NULL) {
3263 			err = got_error_from_errno("got_opentemp");
3264 			goto done;
3265 		}
3266 	}
3267 
3268 	err = got_object_open_as_commit(&commit2, repo, commit_id2);
3269 	if (err)
3270 		goto done;
3271 
3272 	err = got_object_id_by_path(&tree_id2, repo, commit2,
3273 	    worktree->path_prefix);
3274 	if (err)
3275 		goto done;
3276 
3277 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
3278 	if (err)
3279 		goto done;
3280 
3281 	f2 = got_opentemp();
3282 	if (f2 == NULL) {
3283 		err = got_error_from_errno("got_opentemp");
3284 		goto done;
3285 	}
3286 
3287 	fd1 = got_opentempfd();
3288 	if (fd1 == -1) {
3289 		err = got_error_from_errno("got_opentempfd");
3290 		goto done;
3291 	}
3292 
3293 	fd2 = got_opentempfd();
3294 	if (fd2 == -1) {
3295 		err = got_error_from_errno("got_opentempfd");
3296 		goto done;
3297 	}
3298 
3299 	cmc_arg.worktree = worktree;
3300 	cmc_arg.fileindex = fileindex;
3301 	cmc_arg.repo = repo;
3302 	err = got_diff_tree(tree1, tree2, f1, f2, fd1, fd2, "", "", repo,
3303 	    check_merge_conflicts, &cmc_arg, 0);
3304 	if (err)
3305 		goto done;
3306 
3307 	arg.worktree = worktree;
3308 	arg.fileindex = fileindex;
3309 	arg.progress_cb = progress_cb;
3310 	arg.progress_arg = progress_arg;
3311 	arg.cancel_cb = cancel_cb;
3312 	arg.cancel_arg = cancel_arg;
3313 	arg.label_orig = label_orig;
3314 	arg.commit_id2 = commit_id2;
3315 	arg.allow_bad_symlinks = 1; /* preserve bad symlinks across merges */
3316 	err = got_diff_tree(tree1, tree2, f1, f2, fd1, fd2, "", "", repo,
3317 	    merge_file_cb, &arg, 1);
3318 	sync_err = sync_fileindex(fileindex, fileindex_path);
3319 	if (sync_err && err == NULL)
3320 		err = sync_err;
3321 done:
3322 	if (commit1)
3323 		got_object_commit_close(commit1);
3324 	if (commit2)
3325 		got_object_commit_close(commit2);
3326 	if (tree1)
3327 		got_object_tree_close(tree1);
3328 	if (tree2)
3329 		got_object_tree_close(tree2);
3330 	if (f1 && fclose(f1) == EOF && err == NULL)
3331 		err = got_error_from_errno("fclose");
3332 	if (f2 && fclose(f2) == EOF && err == NULL)
3333 		err = got_error_from_errno("fclose");
3334 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
3335 		err = got_error_from_errno("close");
3336 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
3337 		err = got_error_from_errno("close");
3338 	free(label_orig);
3339 	return err;
3340 }
3341 
3342 const struct got_error *
3343 got_worktree_merge_files(struct got_worktree *worktree,
3344     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
3345     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
3346     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
3347 {
3348 	const struct got_error *err, *unlockerr;
3349 	char *fileindex_path = NULL;
3350 	struct got_fileindex *fileindex = NULL;
3351 
3352 	err = lock_worktree(worktree, LOCK_EX);
3353 	if (err)
3354 		return err;
3355 
3356 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3357 	if (err)
3358 		goto done;
3359 
3360 	err = got_fileindex_for_each_entry_safe(fileindex, check_mixed_commits,
3361 	    worktree);
3362 	if (err)
3363 		goto done;
3364 
3365 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
3366 	    commit_id2, repo, progress_cb, progress_arg,
3367 	    cancel_cb, cancel_arg);
3368 done:
3369 	if (fileindex)
3370 		got_fileindex_free(fileindex);
3371 	free(fileindex_path);
3372 	unlockerr = lock_worktree(worktree, LOCK_SH);
3373 	if (unlockerr && err == NULL)
3374 		err = unlockerr;
3375 	return err;
3376 }
3377 
3378 struct diff_dir_cb_arg {
3379     struct got_fileindex *fileindex;
3380     struct got_worktree *worktree;
3381     const char *status_path;
3382     size_t status_path_len;
3383     struct got_repository *repo;
3384     got_worktree_status_cb status_cb;
3385     void *status_arg;
3386     got_cancel_cb cancel_cb;
3387     void *cancel_arg;
3388     /* A pathlist containing per-directory pathlists of ignore patterns. */
3389     struct got_pathlist_head *ignores;
3390     int report_unchanged;
3391     int no_ignores;
3392 };
3393 
3394 static const struct got_error *
3395 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
3396     int dirfd, const char *de_name,
3397     got_worktree_status_cb status_cb, void *status_arg,
3398     struct got_repository *repo, int report_unchanged)
3399 {
3400 	const struct got_error *err = NULL;
3401 	unsigned char status = GOT_STATUS_NO_CHANGE;
3402 	unsigned char staged_status;
3403 	struct stat sb;
3404 	struct got_object_id blob_id, commit_id, staged_blob_id;
3405 	struct got_object_id *blob_idp = NULL, *commit_idp = NULL;
3406 	struct got_object_id *staged_blob_idp = NULL;
3407 
3408 	staged_status = get_staged_status(ie);
3409 	err = get_file_status(&status, &sb, ie, abspath, dirfd, de_name, repo);
3410 	if (err)
3411 		return err;
3412 
3413 	if (status == GOT_STATUS_NO_CHANGE &&
3414 	    staged_status == GOT_STATUS_NO_CHANGE && !report_unchanged)
3415 		return NULL;
3416 
3417 	if (got_fileindex_entry_has_blob(ie))
3418 		blob_idp = got_fileindex_entry_get_blob_id(&blob_id, ie);
3419 	if (got_fileindex_entry_has_commit(ie))
3420 		commit_idp = got_fileindex_entry_get_commit_id(&commit_id, ie);
3421 	if (staged_status == GOT_STATUS_ADD ||
3422 	    staged_status == GOT_STATUS_MODIFY) {
3423 		staged_blob_idp = got_fileindex_entry_get_staged_blob_id(
3424 		    &staged_blob_id, ie);
3425 	}
3426 
3427 	return (*status_cb)(status_arg, status, staged_status,
3428 	    ie->path, blob_idp, staged_blob_idp, commit_idp, dirfd, de_name);
3429 }
3430 
3431 static const struct got_error *
3432 status_old_new(void *arg, struct got_fileindex_entry *ie,
3433     struct dirent *de, const char *parent_path, int dirfd)
3434 {
3435 	const struct got_error *err = NULL;
3436 	struct diff_dir_cb_arg *a = arg;
3437 	char *abspath;
3438 
3439 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3440 		return got_error(GOT_ERR_CANCELLED);
3441 
3442 	if (got_path_cmp(parent_path, a->status_path,
3443 	    strlen(parent_path), a->status_path_len) != 0 &&
3444 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
3445 		return NULL;
3446 
3447 	if (parent_path[0]) {
3448 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
3449 		    parent_path, de->d_name) == -1)
3450 			return got_error_from_errno("asprintf");
3451 	} else {
3452 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
3453 		    de->d_name) == -1)
3454 			return got_error_from_errno("asprintf");
3455 	}
3456 
3457 	err = report_file_status(ie, abspath, dirfd, de->d_name,
3458 	    a->status_cb, a->status_arg, a->repo, a->report_unchanged);
3459 	free(abspath);
3460 	return err;
3461 }
3462 
3463 static const struct got_error *
3464 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
3465 {
3466 	struct diff_dir_cb_arg *a = arg;
3467 	struct got_object_id blob_id, commit_id;
3468 	unsigned char status;
3469 
3470 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3471 		return got_error(GOT_ERR_CANCELLED);
3472 
3473 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
3474 		return NULL;
3475 
3476 	got_fileindex_entry_get_blob_id(&blob_id, ie);
3477 	got_fileindex_entry_get_commit_id(&commit_id, ie);
3478 	if (got_fileindex_entry_has_file_on_disk(ie))
3479 		status = GOT_STATUS_MISSING;
3480 	else
3481 		status = GOT_STATUS_DELETE;
3482 	return (*a->status_cb)(a->status_arg, status, get_staged_status(ie),
3483 	    ie->path, &blob_id, NULL, &commit_id, -1, NULL);
3484 }
3485 
3486 static void
3487 free_ignores(struct got_pathlist_head *ignores)
3488 {
3489 	struct got_pathlist_entry *pe;
3490 
3491 	TAILQ_FOREACH(pe, ignores, entry) {
3492 		struct got_pathlist_head *ignorelist = pe->data;
3493 
3494 		got_pathlist_free(ignorelist, GOT_PATHLIST_FREE_PATH);
3495 	}
3496 	got_pathlist_free(ignores, GOT_PATHLIST_FREE_PATH);
3497 }
3498 
3499 static const struct got_error *
3500 read_ignores(struct got_pathlist_head *ignores, const char *path, FILE *f)
3501 {
3502 	const struct got_error *err = NULL;
3503 	struct got_pathlist_entry *pe = NULL;
3504 	struct got_pathlist_head *ignorelist;
3505 	char *line = NULL, *pattern, *dirpath = NULL;
3506 	size_t linesize = 0;
3507 	ssize_t linelen;
3508 
3509 	ignorelist = calloc(1, sizeof(*ignorelist));
3510 	if (ignorelist == NULL)
3511 		return got_error_from_errno("calloc");
3512 	TAILQ_INIT(ignorelist);
3513 
3514 	while ((linelen = getline(&line, &linesize, f)) != -1) {
3515 		if (linelen > 0 && line[linelen - 1] == '\n')
3516 			line[linelen - 1] = '\0';
3517 
3518 		/* Git's ignores may contain comments. */
3519 		if (line[0] == '#')
3520 			continue;
3521 
3522 		/* Git's negated patterns are not (yet?) supported. */
3523 		if (line[0] == '!')
3524 			continue;
3525 
3526 		if (asprintf(&pattern, "%s%s%s", path, path[0] ? "/" : "",
3527 		    line) == -1) {
3528 			err = got_error_from_errno("asprintf");
3529 			goto done;
3530 		}
3531 		err = got_pathlist_insert(NULL, ignorelist, pattern, NULL);
3532 		if (err)
3533 			goto done;
3534 	}
3535 	if (ferror(f)) {
3536 		err = got_error_from_errno("getline");
3537 		goto done;
3538 	}
3539 
3540 	dirpath = strdup(path);
3541 	if (dirpath == NULL) {
3542 		err = got_error_from_errno("strdup");
3543 		goto done;
3544 	}
3545 	err = got_pathlist_insert(&pe, ignores, dirpath, ignorelist);
3546 done:
3547 	free(line);
3548 	if (err || pe == NULL) {
3549 		free(dirpath);
3550 		got_pathlist_free(ignorelist, GOT_PATHLIST_FREE_PATH);
3551 	}
3552 	return err;
3553 }
3554 
3555 static int
3556 match_path(const char *pattern, size_t pattern_len, const char *path,
3557     int flags)
3558 {
3559 	char buf[PATH_MAX];
3560 
3561 	/*
3562 	 * Trailing slashes signify directories.
3563 	 * Append a * to make such patterns conform to fnmatch rules.
3564 	 */
3565 	if (pattern_len > 0 && pattern[pattern_len - 1] == '/') {
3566 		if (snprintf(buf, sizeof(buf), "%s*", pattern) >= sizeof(buf))
3567 			return FNM_NOMATCH; /* XXX */
3568 
3569 		return fnmatch(buf, path, flags);
3570 	}
3571 
3572 	return fnmatch(pattern, path, flags);
3573 }
3574 
3575 static int
3576 match_ignores(struct got_pathlist_head *ignores, const char *path)
3577 {
3578 	struct got_pathlist_entry *pe;
3579 
3580 	/* Handle patterns which match in all directories. */
3581 	TAILQ_FOREACH(pe, ignores, entry) {
3582 		struct got_pathlist_head *ignorelist = pe->data;
3583 		struct got_pathlist_entry *pi;
3584 
3585 		TAILQ_FOREACH(pi, ignorelist, entry) {
3586 			const char *p;
3587 
3588 			if (pi->path_len < 3 ||
3589 			    strncmp(pi->path, "**/", 3) != 0)
3590 				continue;
3591 			p = path;
3592 			while (*p) {
3593 				if (match_path(pi->path + 3,
3594 				    pi->path_len - 3, p,
3595 				    FNM_PATHNAME | FNM_LEADING_DIR)) {
3596 					/* Retry in next directory. */
3597 					while (*p && *p != '/')
3598 						p++;
3599 					while (*p == '/')
3600 						p++;
3601 					continue;
3602 				}
3603 				return 1;
3604 			}
3605 		}
3606 	}
3607 
3608 	/*
3609 	 * The ignores pathlist contains ignore lists from children before
3610 	 * parents, so we can find the most specific ignorelist by walking
3611 	 * ignores backwards.
3612 	 */
3613 	pe = TAILQ_LAST(ignores, got_pathlist_head);
3614 	while (pe) {
3615 		if (got_path_is_child(path, pe->path, pe->path_len)) {
3616 			struct got_pathlist_head *ignorelist = pe->data;
3617 			struct got_pathlist_entry *pi;
3618 			TAILQ_FOREACH(pi, ignorelist, entry) {
3619 				int flags = FNM_LEADING_DIR;
3620 				if (strstr(pi->path, "/**/") == NULL)
3621 					flags |= FNM_PATHNAME;
3622 				if (match_path(pi->path, pi->path_len,
3623 				    path, flags))
3624 					continue;
3625 				return 1;
3626 			}
3627 		}
3628 		pe = TAILQ_PREV(pe, got_pathlist_head, entry);
3629 	}
3630 
3631 	return 0;
3632 }
3633 
3634 static const struct got_error *
3635 add_ignores(struct got_pathlist_head *ignores, const char *root_path,
3636     const char *path, int dirfd, const char *ignores_filename)
3637 {
3638 	const struct got_error *err = NULL;
3639 	char *ignorespath;
3640 	int fd = -1;
3641 	FILE *ignoresfile = NULL;
3642 
3643 	if (asprintf(&ignorespath, "%s/%s%s%s", root_path, path,
3644 	    path[0] ? "/" : "", ignores_filename) == -1)
3645 		return got_error_from_errno("asprintf");
3646 
3647 	if (dirfd != -1) {
3648 		fd = openat(dirfd, ignores_filename,
3649 		    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
3650 		if (fd == -1) {
3651 			if (errno != ENOENT && errno != EACCES)
3652 				err = got_error_from_errno2("openat",
3653 				    ignorespath);
3654 		} else {
3655 			ignoresfile = fdopen(fd, "r");
3656 			if (ignoresfile == NULL)
3657 				err = got_error_from_errno2("fdopen",
3658 				    ignorespath);
3659 			else {
3660 				fd = -1;
3661 				err = read_ignores(ignores, path, ignoresfile);
3662 			}
3663 		}
3664 	} else {
3665 		ignoresfile = fopen(ignorespath, "re");
3666 		if (ignoresfile == NULL) {
3667 			if (errno != ENOENT && errno != EACCES)
3668 				err = got_error_from_errno2("fopen",
3669 				    ignorespath);
3670 		} else
3671 			err = read_ignores(ignores, path, ignoresfile);
3672 	}
3673 
3674 	if (ignoresfile && fclose(ignoresfile) == EOF && err == NULL)
3675 		err = got_error_from_errno2("fclose", path);
3676 	if (fd != -1 && close(fd) == -1 && err == NULL)
3677 		err = got_error_from_errno2("close", path);
3678 	free(ignorespath);
3679 	return err;
3680 }
3681 
3682 static const struct got_error *
3683 status_new(int *ignore, void *arg, struct dirent *de, const char *parent_path,
3684     int dirfd)
3685 {
3686 	const struct got_error *err = NULL;
3687 	struct diff_dir_cb_arg *a = arg;
3688 	char *path = NULL;
3689 
3690 	if (ignore != NULL)
3691 		*ignore = 0;
3692 
3693 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3694 		return got_error(GOT_ERR_CANCELLED);
3695 
3696 	if (parent_path[0]) {
3697 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
3698 			return got_error_from_errno("asprintf");
3699 	} else {
3700 		path = de->d_name;
3701 	}
3702 
3703 	if (de->d_type == DT_DIR) {
3704 		if (!a->no_ignores && ignore != NULL &&
3705 		    match_ignores(a->ignores, path))
3706 			*ignore = 1;
3707 	} else if (!match_ignores(a->ignores, path) &&
3708 	    got_path_is_child(path, a->status_path, a->status_path_len))
3709 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
3710 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3711 	if (parent_path[0])
3712 		free(path);
3713 	return err;
3714 }
3715 
3716 static const struct got_error *
3717 status_traverse(void *arg, const char *path, int dirfd)
3718 {
3719 	const struct got_error *err = NULL;
3720 	struct diff_dir_cb_arg *a = arg;
3721 
3722 	if (a->no_ignores)
3723 		return NULL;
3724 
3725 	err = add_ignores(a->ignores, a->worktree->root_path,
3726 	    path, dirfd, ".cvsignore");
3727 	if (err)
3728 		return err;
3729 
3730 	err = add_ignores(a->ignores, a->worktree->root_path, path,
3731 	    dirfd, ".gitignore");
3732 
3733 	return err;
3734 }
3735 
3736 static const struct got_error *
3737 report_single_file_status(const char *path, const char *ondisk_path,
3738     struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
3739     void *status_arg, struct got_repository *repo, int report_unchanged,
3740     struct got_pathlist_head *ignores, int no_ignores)
3741 {
3742 	struct got_fileindex_entry *ie;
3743 	struct stat sb;
3744 
3745 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
3746 	if (ie)
3747 		return report_file_status(ie, ondisk_path, -1, NULL,
3748 		    status_cb, status_arg, repo, report_unchanged);
3749 
3750 	if (lstat(ondisk_path, &sb) == -1) {
3751 		if (errno != ENOENT)
3752 			return got_error_from_errno2("lstat", ondisk_path);
3753 		return (*status_cb)(status_arg, GOT_STATUS_NONEXISTENT,
3754 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3755 	}
3756 
3757 	if (!no_ignores && match_ignores(ignores, path))
3758 		return NULL;
3759 
3760 	if (S_ISREG(sb.st_mode) || S_ISLNK(sb.st_mode))
3761 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED,
3762 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3763 
3764 	return NULL;
3765 }
3766 
3767 static const struct got_error *
3768 add_ignores_from_parent_paths(struct got_pathlist_head *ignores,
3769     const char *root_path, const char *path)
3770 {
3771 	const struct got_error *err;
3772 	char *parent_path, *next_parent_path = NULL;
3773 
3774 	err = add_ignores(ignores, root_path, "", -1,
3775 	    ".cvsignore");
3776 	if (err)
3777 		return err;
3778 
3779 	err = add_ignores(ignores, root_path, "", -1,
3780 	    ".gitignore");
3781 	if (err)
3782 		return err;
3783 
3784 	err = got_path_dirname(&parent_path, path);
3785 	if (err) {
3786 		if (err->code == GOT_ERR_BAD_PATH)
3787 			return NULL; /* cannot traverse parent */
3788 		return err;
3789 	}
3790 	for (;;) {
3791 		err = add_ignores(ignores, root_path, parent_path, -1,
3792 		    ".cvsignore");
3793 		if (err)
3794 			break;
3795 		err = add_ignores(ignores, root_path, parent_path, -1,
3796 		    ".gitignore");
3797 		if (err)
3798 			break;
3799 		err = got_path_dirname(&next_parent_path, parent_path);
3800 		if (err) {
3801 			if (err->code == GOT_ERR_BAD_PATH)
3802 				err = NULL; /* traversed everything */
3803 			break;
3804 		}
3805 		if (got_path_is_root_dir(parent_path))
3806 			break;
3807 		free(parent_path);
3808 		parent_path = next_parent_path;
3809 		next_parent_path = NULL;
3810 	}
3811 
3812 	free(parent_path);
3813 	free(next_parent_path);
3814 	return err;
3815 }
3816 
3817 static const struct got_error *
3818 worktree_status(struct got_worktree *worktree, const char *path,
3819     struct got_fileindex *fileindex, struct got_repository *repo,
3820     got_worktree_status_cb status_cb, void *status_arg,
3821     got_cancel_cb cancel_cb, void *cancel_arg, int no_ignores,
3822     int report_unchanged)
3823 {
3824 	const struct got_error *err = NULL;
3825 	int fd = -1;
3826 	struct got_fileindex_diff_dir_cb fdiff_cb;
3827 	struct diff_dir_cb_arg arg;
3828 	char *ondisk_path = NULL;
3829 	struct got_pathlist_head ignores;
3830 	struct got_fileindex_entry *ie;
3831 
3832 	TAILQ_INIT(&ignores);
3833 
3834 	if (asprintf(&ondisk_path, "%s%s%s",
3835 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
3836 		return got_error_from_errno("asprintf");
3837 
3838 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
3839 	if (ie) {
3840 		err = report_single_file_status(path, ondisk_path,
3841 		    fileindex, status_cb, status_arg, repo,
3842 		    report_unchanged, &ignores, no_ignores);
3843 		goto done;
3844 	}
3845 
3846 	fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW | O_DIRECTORY | O_CLOEXEC);
3847 	if (fd == -1) {
3848 		if (errno != ENOTDIR && errno != ENOENT && errno != EACCES &&
3849 		    !got_err_open_nofollow_on_symlink())
3850 			err = got_error_from_errno2("open", ondisk_path);
3851 		else {
3852 			if (!no_ignores) {
3853 				err = add_ignores_from_parent_paths(&ignores,
3854 				    worktree->root_path, ondisk_path);
3855 				if (err)
3856 					goto done;
3857 			}
3858 			err = report_single_file_status(path, ondisk_path,
3859 			    fileindex, status_cb, status_arg, repo,
3860 			    report_unchanged, &ignores, no_ignores);
3861 		}
3862 	} else {
3863 		fdiff_cb.diff_old_new = status_old_new;
3864 		fdiff_cb.diff_old = status_old;
3865 		fdiff_cb.diff_new = status_new;
3866 		fdiff_cb.diff_traverse = status_traverse;
3867 		arg.fileindex = fileindex;
3868 		arg.worktree = worktree;
3869 		arg.status_path = path;
3870 		arg.status_path_len = strlen(path);
3871 		arg.repo = repo;
3872 		arg.status_cb = status_cb;
3873 		arg.status_arg = status_arg;
3874 		arg.cancel_cb = cancel_cb;
3875 		arg.cancel_arg = cancel_arg;
3876 		arg.report_unchanged = report_unchanged;
3877 		arg.no_ignores = no_ignores;
3878 		if (!no_ignores) {
3879 			err = add_ignores_from_parent_paths(&ignores,
3880 			    worktree->root_path, path);
3881 			if (err)
3882 				goto done;
3883 		}
3884 		arg.ignores = &ignores;
3885 		err = got_fileindex_diff_dir(fileindex, fd,
3886 		    worktree->root_path, path, repo, &fdiff_cb, &arg);
3887 	}
3888 done:
3889 	free_ignores(&ignores);
3890 	if (fd != -1 && close(fd) == -1 && err == NULL)
3891 		err = got_error_from_errno("close");
3892 	free(ondisk_path);
3893 	return err;
3894 }
3895 
3896 const struct got_error *
3897 got_worktree_status(struct got_worktree *worktree,
3898     struct got_pathlist_head *paths, struct got_repository *repo,
3899     int no_ignores, got_worktree_status_cb status_cb, void *status_arg,
3900     got_cancel_cb cancel_cb, void *cancel_arg)
3901 {
3902 	const struct got_error *err = NULL;
3903 	char *fileindex_path = NULL;
3904 	struct got_fileindex *fileindex = NULL;
3905 	struct got_pathlist_entry *pe;
3906 
3907 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3908 	if (err)
3909 		return err;
3910 
3911 	TAILQ_FOREACH(pe, paths, entry) {
3912 		err = worktree_status(worktree, pe->path, fileindex, repo,
3913 			status_cb, status_arg, cancel_cb, cancel_arg,
3914 			no_ignores, 0);
3915 		if (err)
3916 			break;
3917 	}
3918 	free(fileindex_path);
3919 	got_fileindex_free(fileindex);
3920 	return err;
3921 }
3922 
3923 const struct got_error *
3924 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
3925     const char *arg)
3926 {
3927 	const struct got_error *err = NULL;
3928 	char *resolved = NULL, *cwd = NULL, *path = NULL;
3929 	size_t len;
3930 	struct stat sb;
3931 	char *abspath = NULL;
3932 	char canonpath[PATH_MAX];
3933 
3934 	*wt_path = NULL;
3935 
3936 	cwd = getcwd(NULL, 0);
3937 	if (cwd == NULL)
3938 		return got_error_from_errno("getcwd");
3939 
3940 	if (lstat(arg, &sb) == -1) {
3941 		if (errno != ENOENT) {
3942 			err = got_error_from_errno2("lstat", arg);
3943 			goto done;
3944 		}
3945 		sb.st_mode = 0;
3946 	}
3947 	if (S_ISLNK(sb.st_mode)) {
3948 		/*
3949 		 * We cannot use realpath(3) with symlinks since we want to
3950 		 * operate on the symlink itself.
3951 		 * But we can make the path absolute, assuming it is relative
3952 		 * to the current working directory, and then canonicalize it.
3953 		 */
3954 		if (!got_path_is_absolute(arg)) {
3955 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3956 				err = got_error_from_errno("asprintf");
3957 				goto done;
3958 			}
3959 
3960 		}
3961 		err = got_canonpath(abspath ? abspath : arg, canonpath,
3962 		    sizeof(canonpath));
3963 		if (err)
3964 			goto done;
3965 		resolved = strdup(canonpath);
3966 		if (resolved == NULL) {
3967 			err = got_error_from_errno("strdup");
3968 			goto done;
3969 		}
3970 	} else {
3971 		resolved = realpath(arg, NULL);
3972 		if (resolved == NULL) {
3973 			if (errno != ENOENT) {
3974 				err = got_error_from_errno2("realpath", arg);
3975 				goto done;
3976 			}
3977 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3978 				err = got_error_from_errno("asprintf");
3979 				goto done;
3980 			}
3981 			err = got_canonpath(abspath, canonpath,
3982 			    sizeof(canonpath));
3983 			if (err)
3984 				goto done;
3985 			resolved = strdup(canonpath);
3986 			if (resolved == NULL) {
3987 				err = got_error_from_errno("strdup");
3988 				goto done;
3989 			}
3990 		}
3991 	}
3992 
3993 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
3994 	    strlen(got_worktree_get_root_path(worktree)))) {
3995 		err = got_error_path(resolved, GOT_ERR_BAD_PATH);
3996 		goto done;
3997 	}
3998 
3999 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
4000 		err = got_path_skip_common_ancestor(&path,
4001 		    got_worktree_get_root_path(worktree), resolved);
4002 		if (err)
4003 			goto done;
4004 	} else {
4005 		path = strdup("");
4006 		if (path == NULL) {
4007 			err = got_error_from_errno("strdup");
4008 			goto done;
4009 		}
4010 	}
4011 
4012 	/* XXX status walk can't deal with trailing slash! */
4013 	len = strlen(path);
4014 	while (len > 0 && path[len - 1] == '/') {
4015 		path[len - 1] = '\0';
4016 		len--;
4017 	}
4018 done:
4019 	free(abspath);
4020 	free(resolved);
4021 	free(cwd);
4022 	if (err == NULL)
4023 		*wt_path = path;
4024 	else
4025 		free(path);
4026 	return err;
4027 }
4028 
4029 struct schedule_addition_args {
4030 	struct got_worktree *worktree;
4031 	struct got_fileindex *fileindex;
4032 	got_worktree_checkout_cb progress_cb;
4033 	void *progress_arg;
4034 	struct got_repository *repo;
4035 };
4036 
4037 static const struct got_error *
4038 schedule_addition(void *arg, unsigned char status, unsigned char staged_status,
4039     const char *relpath, struct got_object_id *blob_id,
4040     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
4041     int dirfd, const char *de_name)
4042 {
4043 	struct schedule_addition_args *a = arg;
4044 	const struct got_error *err = NULL;
4045 	struct got_fileindex_entry *ie;
4046 	struct stat sb;
4047 	char *ondisk_path;
4048 
4049 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
4050 	    relpath) == -1)
4051 		return got_error_from_errno("asprintf");
4052 
4053 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4054 	if (ie) {
4055 		err = get_file_status(&status, &sb, ie, ondisk_path, dirfd,
4056 		    de_name, a->repo);
4057 		if (err)
4058 			goto done;
4059 		/* Re-adding an existing entry is a no-op. */
4060 		if (status == GOT_STATUS_ADD)
4061 			goto done;
4062 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4063 		if (err)
4064 			goto done;
4065 	}
4066 
4067 	if (status != GOT_STATUS_UNVERSIONED) {
4068 		if (status == GOT_STATUS_NONEXISTENT)
4069 			err = got_error_set_errno(ENOENT, ondisk_path);
4070 		else
4071 			err = got_error_path(ondisk_path, GOT_ERR_FILE_STATUS);
4072 		goto done;
4073 	}
4074 
4075 	err = got_fileindex_entry_alloc(&ie, relpath);
4076 	if (err)
4077 		goto done;
4078 	err = got_fileindex_entry_update(ie, a->worktree->root_fd,
4079 	    relpath, NULL, NULL, 1);
4080 	if (err) {
4081 		got_fileindex_entry_free(ie);
4082 		goto done;
4083 	}
4084 	err = got_fileindex_entry_add(a->fileindex, ie);
4085 	if (err) {
4086 		got_fileindex_entry_free(ie);
4087 		goto done;
4088 	}
4089 done:
4090 	free(ondisk_path);
4091 	if (err)
4092 		return err;
4093 	if (status == GOT_STATUS_ADD)
4094 		return NULL;
4095 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_ADD, relpath);
4096 }
4097 
4098 const struct got_error *
4099 got_worktree_schedule_add(struct got_worktree *worktree,
4100     struct got_pathlist_head *paths,
4101     got_worktree_checkout_cb progress_cb, void *progress_arg,
4102     struct got_repository *repo, int no_ignores)
4103 {
4104 	struct got_fileindex *fileindex = NULL;
4105 	char *fileindex_path = NULL;
4106 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4107 	struct got_pathlist_entry *pe;
4108 	struct schedule_addition_args saa;
4109 
4110 	err = lock_worktree(worktree, LOCK_EX);
4111 	if (err)
4112 		return err;
4113 
4114 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4115 	if (err)
4116 		goto done;
4117 
4118 	saa.worktree = worktree;
4119 	saa.fileindex = fileindex;
4120 	saa.progress_cb = progress_cb;
4121 	saa.progress_arg = progress_arg;
4122 	saa.repo = repo;
4123 
4124 	TAILQ_FOREACH(pe, paths, entry) {
4125 		err = worktree_status(worktree, pe->path, fileindex, repo,
4126 			schedule_addition, &saa, NULL, NULL, no_ignores, 0);
4127 		if (err)
4128 			break;
4129 	}
4130 	sync_err = sync_fileindex(fileindex, fileindex_path);
4131 	if (sync_err && err == NULL)
4132 		err = sync_err;
4133 done:
4134 	free(fileindex_path);
4135 	if (fileindex)
4136 		got_fileindex_free(fileindex);
4137 	unlockerr = lock_worktree(worktree, LOCK_SH);
4138 	if (unlockerr && err == NULL)
4139 		err = unlockerr;
4140 	return err;
4141 }
4142 
4143 struct schedule_deletion_args {
4144 	struct got_worktree *worktree;
4145 	struct got_fileindex *fileindex;
4146 	got_worktree_delete_cb progress_cb;
4147 	void *progress_arg;
4148 	struct got_repository *repo;
4149 	int delete_local_mods;
4150 	int keep_on_disk;
4151 	int ignore_missing_paths;
4152 	const char *status_codes;
4153 };
4154 
4155 static const struct got_error *
4156 schedule_for_deletion(void *arg, unsigned char status,
4157     unsigned char staged_status, const char *relpath,
4158     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
4159     struct got_object_id *commit_id, int dirfd, const char *de_name)
4160 {
4161 	struct schedule_deletion_args *a = arg;
4162 	const struct got_error *err = NULL;
4163 	struct got_fileindex_entry *ie = NULL;
4164 	struct stat sb;
4165 	char *ondisk_path;
4166 
4167 	if (status == GOT_STATUS_NONEXISTENT) {
4168 		if (a->ignore_missing_paths)
4169 			return NULL;
4170 		return got_error_set_errno(ENOENT, relpath);
4171 	}
4172 
4173 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4174 	if (ie == NULL)
4175 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
4176 
4177 	staged_status = get_staged_status(ie);
4178 	if (staged_status != GOT_STATUS_NO_CHANGE) {
4179 		if (staged_status == GOT_STATUS_DELETE)
4180 			return NULL;
4181 		return got_error_path(relpath, GOT_ERR_FILE_STAGED);
4182 	}
4183 
4184 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
4185 	    relpath) == -1)
4186 		return got_error_from_errno("asprintf");
4187 
4188 	err = get_file_status(&status, &sb, ie, ondisk_path, dirfd, de_name,
4189 	    a->repo);
4190 	if (err)
4191 		goto done;
4192 
4193 	if (a->status_codes) {
4194 		size_t ncodes = strlen(a->status_codes);
4195 		int i;
4196 		for (i = 0; i < ncodes ; i++) {
4197 			if (status == a->status_codes[i])
4198 				break;
4199 		}
4200 		if (i == ncodes) {
4201 			/* Do not delete files in non-matching status. */
4202 			free(ondisk_path);
4203 			return NULL;
4204 		}
4205 		if (a->status_codes[i] != GOT_STATUS_MODIFY &&
4206 		    a->status_codes[i] != GOT_STATUS_MISSING) {
4207 			static char msg[64];
4208 			snprintf(msg, sizeof(msg),
4209 			    "invalid status code '%c'", a->status_codes[i]);
4210 			err = got_error_msg(GOT_ERR_FILE_STATUS, msg);
4211 			goto done;
4212 		}
4213 	}
4214 
4215 	if (status != GOT_STATUS_NO_CHANGE) {
4216 		if (status == GOT_STATUS_DELETE)
4217 			goto done;
4218 		if (status == GOT_STATUS_MODIFY && !a->delete_local_mods) {
4219 			err = got_error_path(relpath, GOT_ERR_FILE_MODIFIED);
4220 			goto done;
4221 		}
4222 		if (status == GOT_STATUS_MISSING && !a->ignore_missing_paths) {
4223 			err = got_error_set_errno(ENOENT, relpath);
4224 			goto done;
4225 		}
4226 		if (status != GOT_STATUS_MODIFY &&
4227 		    status != GOT_STATUS_MISSING) {
4228 			err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4229 			goto done;
4230 		}
4231 	}
4232 
4233 	if (!a->keep_on_disk && status != GOT_STATUS_MISSING) {
4234 		size_t root_len;
4235 
4236 		if (dirfd != -1) {
4237 			if (unlinkat(dirfd, de_name, 0) == -1) {
4238 				err = got_error_from_errno2("unlinkat",
4239 				    ondisk_path);
4240 				goto done;
4241 			}
4242 		} else if (unlink(ondisk_path) == -1) {
4243 			err = got_error_from_errno2("unlink", ondisk_path);
4244 			goto done;
4245 		}
4246 
4247 		root_len = strlen(a->worktree->root_path);
4248 		do {
4249 			char *parent;
4250 			err = got_path_dirname(&parent, ondisk_path);
4251 			if (err)
4252 				goto done;
4253 			free(ondisk_path);
4254 			ondisk_path = parent;
4255 			if (rmdir(ondisk_path) == -1) {
4256 				if (errno != ENOTEMPTY)
4257 					err = got_error_from_errno2("rmdir",
4258 					    ondisk_path);
4259 				break;
4260 			}
4261 		} while (got_path_cmp(ondisk_path, a->worktree->root_path,
4262 		    strlen(ondisk_path), root_len) != 0);
4263 	}
4264 
4265 	got_fileindex_entry_mark_deleted_from_disk(ie);
4266 done:
4267 	free(ondisk_path);
4268 	if (err)
4269 		return err;
4270 	if (status == GOT_STATUS_DELETE)
4271 		return NULL;
4272 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_DELETE,
4273 	    staged_status, relpath);
4274 }
4275 
4276 const struct got_error *
4277 got_worktree_schedule_delete(struct got_worktree *worktree,
4278     struct got_pathlist_head *paths, int delete_local_mods,
4279     const char *status_codes,
4280     got_worktree_delete_cb progress_cb, void *progress_arg,
4281     struct got_repository *repo, int keep_on_disk, int ignore_missing_paths)
4282 {
4283 	struct got_fileindex *fileindex = NULL;
4284 	char *fileindex_path = NULL;
4285 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4286 	struct got_pathlist_entry *pe;
4287 	struct schedule_deletion_args sda;
4288 
4289 	err = lock_worktree(worktree, LOCK_EX);
4290 	if (err)
4291 		return err;
4292 
4293 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4294 	if (err)
4295 		goto done;
4296 
4297 	sda.worktree = worktree;
4298 	sda.fileindex = fileindex;
4299 	sda.progress_cb = progress_cb;
4300 	sda.progress_arg = progress_arg;
4301 	sda.repo = repo;
4302 	sda.delete_local_mods = delete_local_mods;
4303 	sda.keep_on_disk = keep_on_disk;
4304 	sda.ignore_missing_paths = ignore_missing_paths;
4305 	sda.status_codes = status_codes;
4306 
4307 	TAILQ_FOREACH(pe, paths, entry) {
4308 		err = worktree_status(worktree, pe->path, fileindex, repo,
4309 			schedule_for_deletion, &sda, NULL, NULL, 1, 1);
4310 		if (err)
4311 			break;
4312 	}
4313 	sync_err = sync_fileindex(fileindex, fileindex_path);
4314 	if (sync_err && err == NULL)
4315 		err = sync_err;
4316 done:
4317 	free(fileindex_path);
4318 	if (fileindex)
4319 		got_fileindex_free(fileindex);
4320 	unlockerr = lock_worktree(worktree, LOCK_SH);
4321 	if (unlockerr && err == NULL)
4322 		err = unlockerr;
4323 	return err;
4324 }
4325 
4326 static const struct got_error *
4327 copy_one_line(FILE *infile, FILE *outfile, FILE *rejectfile)
4328 {
4329 	const struct got_error *err = NULL;
4330 	char *line = NULL;
4331 	size_t linesize = 0, n;
4332 	ssize_t linelen;
4333 
4334 	linelen = getline(&line, &linesize, infile);
4335 	if (linelen == -1) {
4336 		if (ferror(infile)) {
4337 			err = got_error_from_errno("getline");
4338 			goto done;
4339 		}
4340 		return NULL;
4341 	}
4342 	if (outfile) {
4343 		n = fwrite(line, 1, linelen, outfile);
4344 		if (n != linelen) {
4345 			err = got_ferror(outfile, GOT_ERR_IO);
4346 			goto done;
4347 		}
4348 	}
4349 	if (rejectfile) {
4350 		n = fwrite(line, 1, linelen, rejectfile);
4351 		if (n != linelen)
4352 			err = got_ferror(rejectfile, GOT_ERR_IO);
4353 	}
4354 done:
4355 	free(line);
4356 	return err;
4357 }
4358 
4359 static const struct got_error *
4360 skip_one_line(FILE *f)
4361 {
4362 	char *line = NULL;
4363 	size_t linesize = 0;
4364 	ssize_t linelen;
4365 
4366 	linelen = getline(&line, &linesize, f);
4367 	if (linelen == -1) {
4368 		if (ferror(f))
4369 			return got_error_from_errno("getline");
4370 		return NULL;
4371 	}
4372 	free(line);
4373 	return NULL;
4374 }
4375 
4376 static const struct got_error *
4377 copy_change(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4378     int start_old, int end_old, int start_new, int end_new,
4379     FILE *outfile, FILE *rejectfile)
4380 {
4381 	const struct got_error *err;
4382 
4383 	/* Copy old file's lines leading up to patch. */
4384 	while (!feof(f1) && *line_cur1 < start_old) {
4385 		err = copy_one_line(f1, outfile, NULL);
4386 		if (err)
4387 			return err;
4388 		(*line_cur1)++;
4389 	}
4390 	/* Skip new file's lines leading up to patch. */
4391 	while (!feof(f2) && *line_cur2 < start_new) {
4392 		if (rejectfile)
4393 			err = copy_one_line(f2, NULL, rejectfile);
4394 		else
4395 			err = skip_one_line(f2);
4396 		if (err)
4397 			return err;
4398 		(*line_cur2)++;
4399 	}
4400 	/* Copy patched lines. */
4401 	while (!feof(f2) && *line_cur2 <= end_new) {
4402 		err = copy_one_line(f2, outfile, NULL);
4403 		if (err)
4404 			return err;
4405 		(*line_cur2)++;
4406 	}
4407 	/* Skip over old file's replaced lines. */
4408 	while (!feof(f1) && *line_cur1 <= end_old) {
4409 		if (rejectfile)
4410 			err = copy_one_line(f1, NULL, rejectfile);
4411 		else
4412 			err = skip_one_line(f1);
4413 		if (err)
4414 			return err;
4415 		(*line_cur1)++;
4416 	}
4417 
4418 	return NULL;
4419 }
4420 
4421 static const struct got_error *
4422 copy_remaining_content(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4423     FILE *outfile, FILE *rejectfile)
4424 {
4425 	const struct got_error *err;
4426 
4427 	if (outfile) {
4428 		/* Copy old file's lines until EOF. */
4429 		while (!feof(f1)) {
4430 			err = copy_one_line(f1, outfile, NULL);
4431 			if (err)
4432 				return err;
4433 			(*line_cur1)++;
4434 		}
4435 	}
4436 	if (rejectfile) {
4437 		/* Copy new file's lines until EOF. */
4438 		while (!feof(f2)) {
4439 			err = copy_one_line(f2, NULL, rejectfile);
4440 			if (err)
4441 				return err;
4442 			(*line_cur2)++;
4443 		}
4444 	}
4445 
4446 	return NULL;
4447 }
4448 
4449 static const struct got_error *
4450 apply_or_reject_change(int *choice, int *nchunks_used,
4451     struct diff_result *diff_result, int n,
4452     const char *relpath, FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4453     FILE *outfile, FILE *rejectfile, int changeno, int nchanges,
4454     got_worktree_patch_cb patch_cb, void *patch_arg)
4455 {
4456 	const struct got_error *err = NULL;
4457 	struct diff_chunk_context cc = {};
4458 	int start_old, end_old, start_new, end_new;
4459 	FILE *hunkfile;
4460 	struct diff_output_unidiff_state *diff_state;
4461 	struct diff_input_info diff_info;
4462 	int rc;
4463 
4464 	*choice = GOT_PATCH_CHOICE_NONE;
4465 
4466 	/* Get changed line numbers without context lines for copy_change(). */
4467 	diff_chunk_context_load_change(&cc, NULL, diff_result, n, 0);
4468 	start_old = cc.left.start;
4469 	end_old = cc.left.end;
4470 	start_new = cc.right.start;
4471 	end_new = cc.right.end;
4472 
4473 	/* Get the same change with context lines for display. */
4474 	memset(&cc, 0, sizeof(cc));
4475 	diff_chunk_context_load_change(&cc, nchunks_used, diff_result, n, 3);
4476 
4477 	memset(&diff_info, 0, sizeof(diff_info));
4478 	diff_info.left_path = relpath;
4479 	diff_info.right_path = relpath;
4480 
4481 	diff_state = diff_output_unidiff_state_alloc();
4482 	if (diff_state == NULL)
4483 		return got_error_set_errno(ENOMEM,
4484 		    "diff_output_unidiff_state_alloc");
4485 
4486 	hunkfile = got_opentemp();
4487 	if (hunkfile == NULL) {
4488 		err = got_error_from_errno("got_opentemp");
4489 		goto done;
4490 	}
4491 
4492 	rc = diff_output_unidiff_chunk(NULL, hunkfile, diff_state, &diff_info,
4493 	    diff_result, &cc);
4494 	if (rc != DIFF_RC_OK) {
4495 		err = got_error_set_errno(rc, "diff_output_unidiff_chunk");
4496 		goto done;
4497 	}
4498 
4499 	if (fseek(hunkfile, 0L, SEEK_SET) == -1) {
4500 		err = got_ferror(hunkfile, GOT_ERR_IO);
4501 		goto done;
4502 	}
4503 
4504 	err = (*patch_cb)(choice, patch_arg, GOT_STATUS_MODIFY, relpath,
4505 	    hunkfile, changeno, nchanges);
4506 	if (err)
4507 		goto done;
4508 
4509 	switch (*choice) {
4510 	case GOT_PATCH_CHOICE_YES:
4511 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4512 		    end_old, start_new, end_new, outfile, rejectfile);
4513 		break;
4514 	case GOT_PATCH_CHOICE_NO:
4515 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4516 		    end_old, start_new, end_new, rejectfile, outfile);
4517 		break;
4518 	case GOT_PATCH_CHOICE_QUIT:
4519 		break;
4520 	default:
4521 		err = got_error(GOT_ERR_PATCH_CHOICE);
4522 		break;
4523 	}
4524 done:
4525 	diff_output_unidiff_state_free(diff_state);
4526 	if (hunkfile && fclose(hunkfile) == EOF && err == NULL)
4527 		err = got_error_from_errno("fclose");
4528 	return err;
4529 }
4530 
4531 struct revert_file_args {
4532 	struct got_worktree *worktree;
4533 	struct got_fileindex *fileindex;
4534 	got_worktree_checkout_cb progress_cb;
4535 	void *progress_arg;
4536 	got_worktree_patch_cb patch_cb;
4537 	void *patch_arg;
4538 	struct got_repository *repo;
4539 	int unlink_added_files;
4540 };
4541 
4542 static const struct got_error *
4543 create_patched_content(char **path_outfile, int reverse_patch,
4544     struct got_object_id *blob_id, const char *path2,
4545     int dirfd2, const char *de_name2,
4546     const char *relpath, struct got_repository *repo,
4547     got_worktree_patch_cb patch_cb, void *patch_arg)
4548 {
4549 	const struct got_error *err, *free_err;
4550 	struct got_blob_object *blob = NULL;
4551 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL;
4552 	int fd = -1, fd2 = -1;
4553 	char link_target[PATH_MAX];
4554 	ssize_t link_len = 0;
4555 	char *path1 = NULL, *id_str = NULL;
4556 	struct stat sb2;
4557 	struct got_diffreg_result *diffreg_result = NULL;
4558 	int line_cur1 = 1, line_cur2 = 1, have_content = 0;
4559 	int i = 0, n = 0, nchunks_used = 0, nchanges = 0;
4560 
4561 	*path_outfile = NULL;
4562 
4563 	err = got_object_id_str(&id_str, blob_id);
4564 	if (err)
4565 		return err;
4566 
4567 	if (dirfd2 != -1) {
4568 		fd2 = openat(dirfd2, de_name2,
4569 		    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
4570 		if (fd2 == -1) {
4571 			if (!got_err_open_nofollow_on_symlink()) {
4572 				err = got_error_from_errno2("openat", path2);
4573 				goto done;
4574 			}
4575 			link_len = readlinkat(dirfd2, de_name2,
4576 			    link_target, sizeof(link_target));
4577 			if (link_len == -1) {
4578 				return got_error_from_errno2("readlinkat",
4579 				    path2);
4580 			}
4581 			sb2.st_mode = S_IFLNK;
4582 			sb2.st_size = link_len;
4583 		}
4584 	} else {
4585 		fd2 = open(path2, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
4586 		if (fd2 == -1) {
4587 			if (!got_err_open_nofollow_on_symlink()) {
4588 				err = got_error_from_errno2("open", path2);
4589 				goto done;
4590 			}
4591 			link_len = readlink(path2, link_target,
4592 			    sizeof(link_target));
4593 			if (link_len == -1)
4594 				return got_error_from_errno2("readlink", path2);
4595 			sb2.st_mode = S_IFLNK;
4596 			sb2.st_size = link_len;
4597 		}
4598 	}
4599 	if (fd2 != -1) {
4600 		if (fstat(fd2, &sb2) == -1) {
4601 			err = got_error_from_errno2("fstat", path2);
4602 			goto done;
4603 		}
4604 
4605 		f2 = fdopen(fd2, "r");
4606 		if (f2 == NULL) {
4607 			err = got_error_from_errno2("fdopen", path2);
4608 			goto done;
4609 		}
4610 		fd2 = -1;
4611 	} else {
4612 		size_t n;
4613 		f2 = got_opentemp();
4614 		if (f2 == NULL) {
4615 			err = got_error_from_errno2("got_opentemp", path2);
4616 			goto done;
4617 		}
4618 		n = fwrite(link_target, 1, link_len, f2);
4619 		if (n != link_len) {
4620 			err = got_ferror(f2, GOT_ERR_IO);
4621 			goto done;
4622 		}
4623 		if (fflush(f2) == EOF) {
4624 			err = got_error_from_errno("fflush");
4625 			goto done;
4626 		}
4627 		rewind(f2);
4628 	}
4629 
4630 	fd = got_opentempfd();
4631 	if (fd == -1) {
4632 		err = got_error_from_errno("got_opentempfd");
4633 		goto done;
4634 	}
4635 
4636 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192, fd);
4637 	if (err)
4638 		goto done;
4639 
4640 	err = got_opentemp_named(&path1, &f1, "got-patched-blob", "");
4641 	if (err)
4642 		goto done;
4643 
4644 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
4645 	if (err)
4646 		goto done;
4647 
4648 	err = got_diff_files(&diffreg_result, f1, 1, id_str, f2, 1, path2,
4649 	    3, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
4650 	if (err)
4651 		goto done;
4652 
4653 	err = got_opentemp_named(path_outfile, &outfile, "got-patched-content",
4654 	    "");
4655 	if (err)
4656 		goto done;
4657 
4658 	if (fseek(f1, 0L, SEEK_SET) == -1)
4659 		return got_ferror(f1, GOT_ERR_IO);
4660 	if (fseek(f2, 0L, SEEK_SET) == -1)
4661 		return got_ferror(f2, GOT_ERR_IO);
4662 
4663 	/* Count the number of actual changes in the diff result. */
4664 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4665 		struct diff_chunk_context cc = {};
4666 		diff_chunk_context_load_change(&cc, &nchunks_used,
4667 		    diffreg_result->result, n, 0);
4668 		nchanges++;
4669 	}
4670 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4671 		int choice;
4672 		err = apply_or_reject_change(&choice, &nchunks_used,
4673 		    diffreg_result->result, n, relpath, f1, f2,
4674 		    &line_cur1, &line_cur2,
4675 		    reverse_patch ? NULL : outfile,
4676 		    reverse_patch ? outfile : NULL,
4677 		    ++i, nchanges, patch_cb, patch_arg);
4678 		if (err)
4679 			goto done;
4680 		if (choice == GOT_PATCH_CHOICE_YES)
4681 			have_content = 1;
4682 		else if (choice == GOT_PATCH_CHOICE_QUIT)
4683 			break;
4684 	}
4685 	if (have_content) {
4686 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
4687 		    reverse_patch ? NULL : outfile,
4688 		    reverse_patch ? outfile : NULL);
4689 		if (err)
4690 			goto done;
4691 
4692 		if (!S_ISLNK(sb2.st_mode)) {
4693 			mode_t mode;
4694 
4695 			mode = apply_umask(sb2.st_mode);
4696 			if (fchmod(fileno(outfile), mode) == -1) {
4697 				err = got_error_from_errno2("fchmod", path2);
4698 				goto done;
4699 			}
4700 		}
4701 	}
4702 done:
4703 	free(id_str);
4704 	if (fd != -1 && close(fd) == -1 && err == NULL)
4705 		err = got_error_from_errno("close");
4706 	if (blob)
4707 		got_object_blob_close(blob);
4708 	free_err = got_diffreg_result_free(diffreg_result);
4709 	if (err == NULL)
4710 		err = free_err;
4711 	if (f1 && fclose(f1) == EOF && err == NULL)
4712 		err = got_error_from_errno2("fclose", path1);
4713 	if (f2 && fclose(f2) == EOF && err == NULL)
4714 		err = got_error_from_errno2("fclose", path2);
4715 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
4716 		err = got_error_from_errno2("close", path2);
4717 	if (outfile && fclose(outfile) == EOF && err == NULL)
4718 		err = got_error_from_errno2("fclose", *path_outfile);
4719 	if (path1 && unlink(path1) == -1 && err == NULL)
4720 		err = got_error_from_errno2("unlink", path1);
4721 	if (err || !have_content) {
4722 		if (*path_outfile && unlink(*path_outfile) == -1 && err == NULL)
4723 			err = got_error_from_errno2("unlink", *path_outfile);
4724 		free(*path_outfile);
4725 		*path_outfile = NULL;
4726 	}
4727 	free(path1);
4728 	return err;
4729 }
4730 
4731 static const struct got_error *
4732 revert_file(void *arg, unsigned char status, unsigned char staged_status,
4733     const char *relpath, struct got_object_id *blob_id,
4734     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
4735     int dirfd, const char *de_name)
4736 {
4737 	struct revert_file_args *a = arg;
4738 	const struct got_error *err = NULL;
4739 	char *parent_path = NULL;
4740 	struct got_fileindex_entry *ie;
4741 	struct got_commit_object *base_commit = NULL;
4742 	struct got_tree_object *tree = NULL;
4743 	struct got_object_id *tree_id = NULL;
4744 	const struct got_tree_entry *te = NULL;
4745 	char *tree_path = NULL, *te_name;
4746 	char *ondisk_path = NULL, *path_content = NULL;
4747 	struct got_blob_object *blob = NULL;
4748 	int fd = -1;
4749 
4750 	/* Reverting a staged deletion is a no-op. */
4751 	if (status == GOT_STATUS_DELETE &&
4752 	    staged_status != GOT_STATUS_NO_CHANGE)
4753 		return NULL;
4754 
4755 	if (status == GOT_STATUS_UNVERSIONED)
4756 		return (*a->progress_cb)(a->progress_arg,
4757 		    GOT_STATUS_UNVERSIONED, relpath);
4758 
4759 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4760 	if (ie == NULL)
4761 		return got_error_path(relpath, GOT_ERR_BAD_PATH);
4762 
4763 	/* Construct in-repository path of tree which contains this blob. */
4764 	err = got_path_dirname(&parent_path, ie->path);
4765 	if (err) {
4766 		if (err->code != GOT_ERR_BAD_PATH)
4767 			goto done;
4768 		parent_path = strdup("/");
4769 		if (parent_path == NULL) {
4770 			err = got_error_from_errno("strdup");
4771 			goto done;
4772 		}
4773 	}
4774 	if (got_path_is_root_dir(a->worktree->path_prefix)) {
4775 		tree_path = strdup(parent_path);
4776 		if (tree_path == NULL) {
4777 			err = got_error_from_errno("strdup");
4778 			goto done;
4779 		}
4780 	} else {
4781 		if (got_path_is_root_dir(parent_path)) {
4782 			tree_path = strdup(a->worktree->path_prefix);
4783 			if (tree_path == NULL) {
4784 				err = got_error_from_errno("strdup");
4785 				goto done;
4786 			}
4787 		} else {
4788 			if (asprintf(&tree_path, "%s/%s",
4789 			    a->worktree->path_prefix, parent_path) == -1) {
4790 				err = got_error_from_errno("asprintf");
4791 				goto done;
4792 			}
4793 		}
4794 	}
4795 
4796 	err = got_object_open_as_commit(&base_commit, a->repo,
4797 	    a->worktree->base_commit_id);
4798 	if (err)
4799 		goto done;
4800 
4801 	err = got_object_id_by_path(&tree_id, a->repo, base_commit, tree_path);
4802 	if (err) {
4803 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
4804 		    (status == GOT_STATUS_ADD ||
4805 		    staged_status == GOT_STATUS_ADD)))
4806 			goto done;
4807 	} else {
4808 		err = got_object_open_as_tree(&tree, a->repo, tree_id);
4809 		if (err)
4810 			goto done;
4811 
4812 		err = got_path_basename(&te_name, ie->path);
4813 		if (err)
4814 			goto done;
4815 
4816 		te = got_object_tree_find_entry(tree, te_name);
4817 		free(te_name);
4818 		if (te == NULL && status != GOT_STATUS_ADD &&
4819 		    staged_status != GOT_STATUS_ADD) {
4820 			err = got_error_path(ie->path, GOT_ERR_NO_TREE_ENTRY);
4821 			goto done;
4822 		}
4823 	}
4824 
4825 	switch (status) {
4826 	case GOT_STATUS_ADD:
4827 		if (a->patch_cb) {
4828 			int choice = GOT_PATCH_CHOICE_NONE;
4829 			err = (*a->patch_cb)(&choice, a->patch_arg,
4830 			    status, ie->path, NULL, 1, 1);
4831 			if (err)
4832 				goto done;
4833 			if (choice != GOT_PATCH_CHOICE_YES)
4834 				break;
4835 		}
4836 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_REVERT,
4837 		    ie->path);
4838 		if (err)
4839 			goto done;
4840 		got_fileindex_entry_remove(a->fileindex, ie);
4841 		if (a->unlink_added_files) {
4842 			if (asprintf(&ondisk_path, "%s/%s",
4843 			    got_worktree_get_root_path(a->worktree),
4844 			    relpath) == -1) {
4845 				err = got_error_from_errno("asprintf");
4846 				goto done;
4847 			}
4848 			if (unlink(ondisk_path) == -1) {
4849 				err = got_error_from_errno2("unlink",
4850 				    ondisk_path);
4851 				break;
4852 			}
4853 		}
4854 		break;
4855 	case GOT_STATUS_DELETE:
4856 		if (a->patch_cb) {
4857 			int choice = GOT_PATCH_CHOICE_NONE;
4858 			err = (*a->patch_cb)(&choice, a->patch_arg,
4859 			    status, ie->path, NULL, 1, 1);
4860 			if (err)
4861 				goto done;
4862 			if (choice != GOT_PATCH_CHOICE_YES)
4863 				break;
4864 		}
4865 		/* fall through */
4866 	case GOT_STATUS_MODIFY:
4867 	case GOT_STATUS_MODE_CHANGE:
4868 	case GOT_STATUS_CONFLICT:
4869 	case GOT_STATUS_MISSING: {
4870 		struct got_object_id id;
4871 		if (staged_status == GOT_STATUS_ADD ||
4872 		    staged_status == GOT_STATUS_MODIFY)
4873 			got_fileindex_entry_get_staged_blob_id(&id, ie);
4874 		else
4875 			got_fileindex_entry_get_blob_id(&id, ie);
4876 		fd = got_opentempfd();
4877 		if (fd == -1) {
4878 			err = got_error_from_errno("got_opentempfd");
4879 			goto done;
4880 		}
4881 
4882 		err = got_object_open_as_blob(&blob, a->repo, &id, 8192, fd);
4883 		if (err)
4884 			goto done;
4885 
4886 		if (asprintf(&ondisk_path, "%s/%s",
4887 		    got_worktree_get_root_path(a->worktree), relpath) == -1) {
4888 			err = got_error_from_errno("asprintf");
4889 			goto done;
4890 		}
4891 
4892 		if (a->patch_cb && (status == GOT_STATUS_MODIFY ||
4893 		    status == GOT_STATUS_CONFLICT)) {
4894 			int is_bad_symlink = 0;
4895 			err = create_patched_content(&path_content, 1, &id,
4896 			    ondisk_path, dirfd, de_name, ie->path, a->repo,
4897 			    a->patch_cb, a->patch_arg);
4898 			if (err || path_content == NULL)
4899 				break;
4900 			if (te && S_ISLNK(te->mode)) {
4901 				if (unlink(path_content) == -1) {
4902 					err = got_error_from_errno2("unlink",
4903 					    path_content);
4904 					break;
4905 				}
4906 				err = install_symlink(&is_bad_symlink,
4907 				    a->worktree, ondisk_path, ie->path,
4908 				    blob, 0, 1, 0, 0, a->repo,
4909 				    a->progress_cb, a->progress_arg);
4910 			} else {
4911 				if (rename(path_content, ondisk_path) == -1) {
4912 					err = got_error_from_errno3("rename",
4913 					    path_content, ondisk_path);
4914 					goto done;
4915 				}
4916 			}
4917 		} else {
4918 			int is_bad_symlink = 0;
4919 			if (te && S_ISLNK(te->mode)) {
4920 				err = install_symlink(&is_bad_symlink,
4921 				    a->worktree, ondisk_path, ie->path,
4922 				    blob, 0, 1, 0, 0, a->repo,
4923 				    a->progress_cb, a->progress_arg);
4924 			} else {
4925 				err = install_blob(a->worktree, ondisk_path,
4926 				    ie->path,
4927 				    te ? te->mode : GOT_DEFAULT_FILE_MODE,
4928 				    got_fileindex_perms_to_st(ie), blob,
4929 				    0, 1, 0, 0, a->repo,
4930 				    a->progress_cb, a->progress_arg);
4931 			}
4932 			if (err)
4933 				goto done;
4934 			if (status == GOT_STATUS_DELETE ||
4935 			    status == GOT_STATUS_MODE_CHANGE) {
4936 				err = got_fileindex_entry_update(ie,
4937 				    a->worktree->root_fd, relpath,
4938 				    blob->id.sha1,
4939 				    a->worktree->base_commit_id->sha1, 1);
4940 				if (err)
4941 					goto done;
4942 			}
4943 			if (is_bad_symlink) {
4944 				got_fileindex_entry_filetype_set(ie,
4945 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
4946 			}
4947 		}
4948 		break;
4949 	}
4950 	default:
4951 		break;
4952 	}
4953 done:
4954 	free(ondisk_path);
4955 	free(path_content);
4956 	free(parent_path);
4957 	free(tree_path);
4958 	if (fd != -1 && close(fd) == -1 && err == NULL)
4959 		err = got_error_from_errno("close");
4960 	if (blob)
4961 		got_object_blob_close(blob);
4962 	if (tree)
4963 		got_object_tree_close(tree);
4964 	free(tree_id);
4965 	if (base_commit)
4966 		got_object_commit_close(base_commit);
4967 	return err;
4968 }
4969 
4970 const struct got_error *
4971 got_worktree_revert(struct got_worktree *worktree,
4972     struct got_pathlist_head *paths,
4973     got_worktree_checkout_cb progress_cb, void *progress_arg,
4974     got_worktree_patch_cb patch_cb, void *patch_arg,
4975     struct got_repository *repo)
4976 {
4977 	struct got_fileindex *fileindex = NULL;
4978 	char *fileindex_path = NULL;
4979 	const struct got_error *err = NULL, *unlockerr = NULL;
4980 	const struct got_error *sync_err = NULL;
4981 	struct got_pathlist_entry *pe;
4982 	struct revert_file_args rfa;
4983 
4984 	err = lock_worktree(worktree, LOCK_EX);
4985 	if (err)
4986 		return err;
4987 
4988 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4989 	if (err)
4990 		goto done;
4991 
4992 	rfa.worktree = worktree;
4993 	rfa.fileindex = fileindex;
4994 	rfa.progress_cb = progress_cb;
4995 	rfa.progress_arg = progress_arg;
4996 	rfa.patch_cb = patch_cb;
4997 	rfa.patch_arg = patch_arg;
4998 	rfa.repo = repo;
4999 	rfa.unlink_added_files = 0;
5000 	TAILQ_FOREACH(pe, paths, entry) {
5001 		err = worktree_status(worktree, pe->path, fileindex, repo,
5002 		    revert_file, &rfa, NULL, NULL, 1, 0);
5003 		if (err)
5004 			break;
5005 	}
5006 	sync_err = sync_fileindex(fileindex, fileindex_path);
5007 	if (sync_err && err == NULL)
5008 		err = sync_err;
5009 done:
5010 	free(fileindex_path);
5011 	if (fileindex)
5012 		got_fileindex_free(fileindex);
5013 	unlockerr = lock_worktree(worktree, LOCK_SH);
5014 	if (unlockerr && err == NULL)
5015 		err = unlockerr;
5016 	return err;
5017 }
5018 
5019 static void
5020 free_commitable(struct got_commitable *ct)
5021 {
5022 	free(ct->path);
5023 	free(ct->in_repo_path);
5024 	free(ct->ondisk_path);
5025 	free(ct->blob_id);
5026 	free(ct->base_blob_id);
5027 	free(ct->staged_blob_id);
5028 	free(ct->base_commit_id);
5029 	free(ct);
5030 }
5031 
5032 struct collect_commitables_arg {
5033 	struct got_pathlist_head *commitable_paths;
5034 	struct got_repository *repo;
5035 	struct got_worktree *worktree;
5036 	struct got_fileindex *fileindex;
5037 	int have_staged_files;
5038 	int allow_bad_symlinks;
5039 	int diff_header_shown;
5040 	int commit_conflicts;
5041 	FILE *diff_outfile;
5042 	FILE *f1;
5043 	FILE *f2;
5044 };
5045 
5046 /*
5047  * Create a file which contains the target path of a symlink so we can feed
5048  * it as content to the diff engine.
5049  */
5050 static const struct got_error *
5051 get_symlink_target_file(int *fd, int dirfd, const char *de_name,
5052     const char *abspath)
5053 {
5054 	const struct got_error *err = NULL;
5055 	char target_path[PATH_MAX];
5056 	ssize_t target_len, outlen;
5057 
5058 	*fd = -1;
5059 
5060 	if (dirfd != -1) {
5061 		target_len = readlinkat(dirfd, de_name, target_path, PATH_MAX);
5062 		if (target_len == -1)
5063 			return got_error_from_errno2("readlinkat", abspath);
5064 	} else {
5065 		target_len = readlink(abspath, target_path, PATH_MAX);
5066 		if (target_len == -1)
5067 			return got_error_from_errno2("readlink", abspath);
5068 	}
5069 
5070 	*fd = got_opentempfd();
5071 	if (*fd == -1)
5072 		return got_error_from_errno("got_opentempfd");
5073 
5074 	outlen = write(*fd, target_path, target_len);
5075 	if (outlen == -1) {
5076 		err = got_error_from_errno("got_opentempfd");
5077 		goto done;
5078 	}
5079 
5080 	if (lseek(*fd, 0, SEEK_SET) == -1) {
5081 		err = got_error_from_errno2("lseek", abspath);
5082 		goto done;
5083 	}
5084 done:
5085 	if (err) {
5086 		close(*fd);
5087 		*fd = -1;
5088 	}
5089 	return err;
5090 }
5091 
5092 static const struct got_error *
5093 append_ct_diff(struct got_commitable *ct, int *diff_header_shown,
5094     FILE *diff_outfile, FILE *f1, FILE *f2, int dirfd, const char *de_name,
5095     int diff_staged, struct got_repository *repo, struct got_worktree *worktree)
5096 {
5097 	const struct got_error *err = NULL;
5098 	struct got_blob_object *blob1 = NULL;
5099 	int fd = -1, fd1 = -1, fd2 = -1;
5100 	FILE *ondisk_file = NULL;
5101 	char *label1 = NULL;
5102 	struct stat sb;
5103 	off_t size1 = 0;
5104 	int f2_exists = 0;
5105 	char *id_str = NULL;
5106 
5107 	memset(&sb, 0, sizeof(sb));
5108 
5109 	if (diff_staged) {
5110 		if (ct->staged_status != GOT_STATUS_MODIFY &&
5111 		    ct->staged_status != GOT_STATUS_ADD &&
5112 		    ct->staged_status != GOT_STATUS_DELETE)
5113 			return NULL;
5114 	} else {
5115 		if (ct->status != GOT_STATUS_MODIFY &&
5116 		    ct->status != GOT_STATUS_ADD &&
5117 		    ct->status != GOT_STATUS_DELETE &&
5118 		    ct->status != GOT_STATUS_CONFLICT)
5119 			return NULL;
5120 	}
5121 
5122 	err = got_opentemp_truncate(f1);
5123 	if (err)
5124 		return got_error_from_errno("got_opentemp_truncate");
5125 	err = got_opentemp_truncate(f2);
5126 	if (err)
5127 		return got_error_from_errno("got_opentemp_truncate");
5128 
5129 	if (!*diff_header_shown) {
5130 		err = got_object_id_str(&id_str, worktree->base_commit_id);
5131 		if (err)
5132 			return err;
5133 		fprintf(diff_outfile, "diff %s%s\n", diff_staged ? "-s " : "",
5134 		    got_worktree_get_root_path(worktree));
5135 		fprintf(diff_outfile, "commit - %s\n", id_str);
5136 		fprintf(diff_outfile, "path + %s%s\n",
5137 		    got_worktree_get_root_path(worktree),
5138 		    diff_staged ? " (staged changes)" : "");
5139 		*diff_header_shown = 1;
5140 	}
5141 
5142 	if (diff_staged) {
5143 		const char *label1 = NULL, *label2 = NULL;
5144 		switch (ct->staged_status) {
5145 		case GOT_STATUS_MODIFY:
5146 			label1 = ct->path;
5147 			label2 = ct->path;
5148 			break;
5149 		case GOT_STATUS_ADD:
5150 			label2 = ct->path;
5151 			break;
5152 		case GOT_STATUS_DELETE:
5153 			label1 = ct->path;
5154 			break;
5155 		default:
5156 			return got_error(GOT_ERR_FILE_STATUS);
5157 		}
5158 		fd1 = got_opentempfd();
5159 		if (fd1 == -1) {
5160 			err = got_error_from_errno("got_opentempfd");
5161 			goto done;
5162 		}
5163 		fd2 = got_opentempfd();
5164 		if (fd2 == -1) {
5165 			err = got_error_from_errno("got_opentempfd");
5166 			goto done;
5167 		}
5168 		err = got_diff_objects_as_blobs(NULL, NULL, f1, f2,
5169 		    fd1, fd2, ct->base_blob_id, ct->staged_blob_id,
5170 		    label1, label2, GOT_DIFF_ALGORITHM_PATIENCE, 3, 0, 0,
5171 		    NULL, repo, diff_outfile);
5172 		goto done;
5173 	}
5174 
5175 	fd1 = got_opentempfd();
5176 	if (fd1 == -1) {
5177 		err = got_error_from_errno("got_opentempfd");
5178 		goto done;
5179 	}
5180 
5181 	if (ct->status != GOT_STATUS_ADD) {
5182 		err = got_object_open_as_blob(&blob1, repo, ct->base_blob_id,
5183 		    8192, fd1);
5184 		if (err)
5185 			goto done;
5186 	}
5187 
5188 	if (ct->status != GOT_STATUS_DELETE) {
5189 		if (dirfd != -1) {
5190 			fd = openat(dirfd, de_name,
5191 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
5192 			if (fd == -1) {
5193 				if (!got_err_open_nofollow_on_symlink()) {
5194 					err = got_error_from_errno2("openat",
5195 					    ct->ondisk_path);
5196 					goto done;
5197 				}
5198 				err = get_symlink_target_file(&fd, dirfd,
5199 				    de_name, ct->ondisk_path);
5200 				if (err)
5201 					goto done;
5202 			}
5203 		} else {
5204 			fd = open(ct->ondisk_path,
5205 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
5206 			if (fd == -1) {
5207 				if (!got_err_open_nofollow_on_symlink()) {
5208 					err = got_error_from_errno2("open",
5209 					    ct->ondisk_path);
5210 					goto done;
5211 				}
5212 				err = get_symlink_target_file(&fd, dirfd,
5213 				    de_name, ct->ondisk_path);
5214 				if (err)
5215 					goto done;
5216 			}
5217 		}
5218 		if (fstatat(fd, ct->ondisk_path, &sb,
5219 		    AT_SYMLINK_NOFOLLOW) == -1) {
5220 			err = got_error_from_errno2("fstatat", ct->ondisk_path);
5221 			goto done;
5222 		}
5223 		ondisk_file = fdopen(fd, "r");
5224 		if (ondisk_file == NULL) {
5225 			err = got_error_from_errno2("fdopen", ct->ondisk_path);
5226 			goto done;
5227 		}
5228 		fd = -1;
5229 		f2_exists = 1;
5230 	}
5231 
5232 	if (blob1) {
5233 		err = got_object_blob_dump_to_file(&size1, NULL, NULL,
5234 		    f1, blob1);
5235 		if (err)
5236 			goto done;
5237 	}
5238 
5239 	err = got_diff_blob_file(blob1, f1, size1, label1,
5240 	    ondisk_file ? ondisk_file : f2, f2_exists, &sb, ct->path,
5241 	    GOT_DIFF_ALGORITHM_PATIENCE, 3, 0, 0, NULL, diff_outfile);
5242 done:
5243 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
5244 		err = got_error_from_errno("close");
5245 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
5246 		err = got_error_from_errno("close");
5247 	if (blob1)
5248 		got_object_blob_close(blob1);
5249 	if (fd != -1 && close(fd) == -1 && err == NULL)
5250 		err = got_error_from_errno("close");
5251 	if (ondisk_file && fclose(ondisk_file) == EOF && err == NULL)
5252 		err = got_error_from_errno("fclose");
5253 	return err;
5254 }
5255 
5256 static const struct got_error *
5257 collect_commitables(void *arg, unsigned char status,
5258     unsigned char staged_status, const char *relpath,
5259     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5260     struct got_object_id *commit_id, int dirfd, const char *de_name)
5261 {
5262 	struct collect_commitables_arg *a = arg;
5263 	const struct got_error *err = NULL;
5264 	struct got_commitable *ct = NULL;
5265 	struct got_pathlist_entry *new = NULL;
5266 	char *parent_path = NULL, *path = NULL;
5267 	struct stat sb;
5268 
5269 	if (a->have_staged_files) {
5270 		if (staged_status != GOT_STATUS_MODIFY &&
5271 		    staged_status != GOT_STATUS_ADD &&
5272 		    staged_status != GOT_STATUS_DELETE)
5273 			return NULL;
5274 	} else {
5275 		if (status == GOT_STATUS_CONFLICT && !a->commit_conflicts) {
5276 			printf("C  %s\n", relpath);
5277 			return got_error(GOT_ERR_COMMIT_CONFLICT);
5278 		}
5279 
5280 		if (status != GOT_STATUS_MODIFY &&
5281 		    status != GOT_STATUS_MODE_CHANGE &&
5282 		    status != GOT_STATUS_ADD &&
5283 		    status != GOT_STATUS_DELETE &&
5284 		    status != GOT_STATUS_CONFLICT)
5285 			return NULL;
5286 	}
5287 
5288 	if (asprintf(&path, "/%s", relpath) == -1) {
5289 		err = got_error_from_errno("asprintf");
5290 		goto done;
5291 	}
5292 	if (strcmp(path, "/") == 0) {
5293 		parent_path = strdup("");
5294 		if (parent_path == NULL)
5295 			return got_error_from_errno("strdup");
5296 	} else {
5297 		err = got_path_dirname(&parent_path, path);
5298 		if (err)
5299 			return err;
5300 	}
5301 
5302 	ct = calloc(1, sizeof(*ct));
5303 	if (ct == NULL) {
5304 		err = got_error_from_errno("calloc");
5305 		goto done;
5306 	}
5307 
5308 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
5309 	    relpath) == -1) {
5310 		err = got_error_from_errno("asprintf");
5311 		goto done;
5312 	}
5313 
5314 	if (staged_status == GOT_STATUS_ADD ||
5315 	    staged_status == GOT_STATUS_MODIFY) {
5316 		struct got_fileindex_entry *ie;
5317 		ie = got_fileindex_entry_get(a->fileindex, path, strlen(path));
5318 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
5319 		case GOT_FILEIDX_MODE_REGULAR_FILE:
5320 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
5321 			ct->mode = S_IFREG;
5322 			break;
5323 		case GOT_FILEIDX_MODE_SYMLINK:
5324 			ct->mode = S_IFLNK;
5325 			break;
5326 		default:
5327 			err = got_error_path(path, GOT_ERR_BAD_FILETYPE);
5328 			goto done;
5329 		}
5330 		ct->mode |= got_fileindex_entry_perms_get(ie);
5331 	} else if (status != GOT_STATUS_DELETE &&
5332 	    staged_status != GOT_STATUS_DELETE) {
5333 		if (dirfd != -1) {
5334 			if (fstatat(dirfd, de_name, &sb,
5335 			    AT_SYMLINK_NOFOLLOW) == -1) {
5336 				err = got_error_from_errno2("fstatat",
5337 				    ct->ondisk_path);
5338 				goto done;
5339 			}
5340 		} else if (lstat(ct->ondisk_path, &sb) == -1) {
5341 			err = got_error_from_errno2("lstat", ct->ondisk_path);
5342 			goto done;
5343 		}
5344 		ct->mode = sb.st_mode;
5345 	}
5346 
5347 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
5348 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
5349 	    relpath) == -1) {
5350 		err = got_error_from_errno("asprintf");
5351 		goto done;
5352 	}
5353 
5354 	if (S_ISLNK(ct->mode) && staged_status == GOT_STATUS_NO_CHANGE &&
5355 	    status == GOT_STATUS_ADD && !a->allow_bad_symlinks) {
5356 		int is_bad_symlink;
5357 		char target_path[PATH_MAX];
5358 		ssize_t target_len;
5359 		target_len = readlink(ct->ondisk_path, target_path,
5360 		    sizeof(target_path));
5361 		if (target_len == -1) {
5362 			err = got_error_from_errno2("readlink",
5363 			    ct->ondisk_path);
5364 			goto done;
5365 		}
5366 		err = is_bad_symlink_target(&is_bad_symlink, target_path,
5367 		    target_len, ct->ondisk_path, a->worktree->root_path);
5368 		if (err)
5369 			goto done;
5370 		if (is_bad_symlink) {
5371 			err = got_error_path(ct->ondisk_path,
5372 			    GOT_ERR_BAD_SYMLINK);
5373 			goto done;
5374 		}
5375 	}
5376 
5377 
5378 	ct->status = status;
5379 	ct->staged_status = staged_status;
5380 	ct->blob_id = NULL; /* will be filled in when blob gets created */
5381 	if (ct->status != GOT_STATUS_ADD &&
5382 	    ct->staged_status != GOT_STATUS_ADD) {
5383 		ct->base_blob_id = got_object_id_dup(blob_id);
5384 		if (ct->base_blob_id == NULL) {
5385 			err = got_error_from_errno("got_object_id_dup");
5386 			goto done;
5387 		}
5388 		ct->base_commit_id = got_object_id_dup(commit_id);
5389 		if (ct->base_commit_id == NULL) {
5390 			err = got_error_from_errno("got_object_id_dup");
5391 			goto done;
5392 		}
5393 	}
5394 	if (ct->staged_status == GOT_STATUS_ADD ||
5395 	    ct->staged_status == GOT_STATUS_MODIFY) {
5396 		ct->staged_blob_id = got_object_id_dup(staged_blob_id);
5397 		if (ct->staged_blob_id == NULL) {
5398 			err = got_error_from_errno("got_object_id_dup");
5399 			goto done;
5400 		}
5401 	}
5402 	ct->path = strdup(path);
5403 	if (ct->path == NULL) {
5404 		err = got_error_from_errno("strdup");
5405 		goto done;
5406 	}
5407 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
5408 	if (err)
5409 		goto done;
5410 
5411 	if (a->diff_outfile && ct && new != NULL) {
5412 		err = append_ct_diff(ct, &a->diff_header_shown,
5413 		    a->diff_outfile, a->f1, a->f2, dirfd, de_name,
5414 		    a->have_staged_files, a->repo, a->worktree);
5415 		if (err)
5416 			goto done;
5417 	}
5418 done:
5419 	if (ct && (err || new == NULL))
5420 		free_commitable(ct);
5421 	free(parent_path);
5422 	free(path);
5423 	return err;
5424 }
5425 
5426 static const struct got_error *write_tree(struct got_object_id **, int *,
5427     struct got_tree_object *, const char *, struct got_pathlist_head *,
5428     got_worktree_status_cb status_cb, void *status_arg,
5429     struct got_repository *);
5430 
5431 static const struct got_error *
5432 write_subtree(struct got_object_id **new_subtree_id, int *nentries,
5433     struct got_tree_entry *te, const char *parent_path,
5434     struct got_pathlist_head *commitable_paths,
5435     got_worktree_status_cb status_cb, void *status_arg,
5436     struct got_repository *repo)
5437 {
5438 	const struct got_error *err = NULL;
5439 	struct got_tree_object *subtree;
5440 	char *subpath;
5441 
5442 	if (asprintf(&subpath, "%s%s%s", parent_path,
5443 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
5444 		return got_error_from_errno("asprintf");
5445 
5446 	err = got_object_open_as_tree(&subtree, repo, &te->id);
5447 	if (err)
5448 		return err;
5449 
5450 	err = write_tree(new_subtree_id, nentries, subtree, subpath,
5451 	    commitable_paths, status_cb, status_arg, repo);
5452 	got_object_tree_close(subtree);
5453 	free(subpath);
5454 	return err;
5455 }
5456 
5457 static const struct got_error *
5458 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
5459 {
5460 	const struct got_error *err = NULL;
5461 	char *ct_parent_path = NULL;
5462 
5463 	*match = 0;
5464 
5465 	if (strchr(ct->in_repo_path, '/') == NULL) {
5466 		*match = got_path_is_root_dir(path);
5467 		return NULL;
5468 	}
5469 
5470 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
5471 	if (err)
5472 		return err;
5473 	*match = (strcmp(path, ct_parent_path) == 0);
5474 	free(ct_parent_path);
5475 	return err;
5476 }
5477 
5478 static mode_t
5479 get_ct_file_mode(struct got_commitable *ct)
5480 {
5481 	if (S_ISLNK(ct->mode))
5482 		return S_IFLNK;
5483 
5484 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
5485 }
5486 
5487 static const struct got_error *
5488 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
5489     struct got_tree_entry *te, struct got_commitable *ct)
5490 {
5491 	const struct got_error *err = NULL;
5492 
5493 	*new_te = NULL;
5494 
5495 	err = got_object_tree_entry_dup(new_te, te);
5496 	if (err)
5497 		goto done;
5498 
5499 	(*new_te)->mode = get_ct_file_mode(ct);
5500 
5501 	if (ct->staged_status == GOT_STATUS_MODIFY)
5502 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5503 		    sizeof((*new_te)->id));
5504 	else
5505 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5506 done:
5507 	if (err && *new_te) {
5508 		free(*new_te);
5509 		*new_te = NULL;
5510 	}
5511 	return err;
5512 }
5513 
5514 static const struct got_error *
5515 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
5516     struct got_commitable *ct)
5517 {
5518 	const struct got_error *err = NULL;
5519 	char *ct_name = NULL;
5520 
5521 	 *new_te = NULL;
5522 
5523 	*new_te = calloc(1, sizeof(**new_te));
5524 	if (*new_te == NULL)
5525 		return got_error_from_errno("calloc");
5526 
5527 	err = got_path_basename(&ct_name, ct->path);
5528 	if (err)
5529 		goto done;
5530 	if (strlcpy((*new_te)->name, ct_name, sizeof((*new_te)->name)) >=
5531 	    sizeof((*new_te)->name)) {
5532 		err = got_error(GOT_ERR_NO_SPACE);
5533 		goto done;
5534 	}
5535 
5536 	(*new_te)->mode = get_ct_file_mode(ct);
5537 
5538 	if (ct->staged_status == GOT_STATUS_ADD)
5539 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5540 		    sizeof((*new_te)->id));
5541 	else
5542 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5543 done:
5544 	free(ct_name);
5545 	if (err && *new_te) {
5546 		free(*new_te);
5547 		*new_te = NULL;
5548 	}
5549 	return err;
5550 }
5551 
5552 static const struct got_error *
5553 insert_tree_entry(struct got_tree_entry *new_te,
5554     struct got_pathlist_head *paths)
5555 {
5556 	const struct got_error *err = NULL;
5557 	struct got_pathlist_entry *new_pe;
5558 
5559 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
5560 	if (err)
5561 		return err;
5562 	if (new_pe == NULL)
5563 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
5564 	return NULL;
5565 }
5566 
5567 static const struct got_error *
5568 report_ct_status(struct got_commitable *ct,
5569     got_worktree_status_cb status_cb, void *status_arg)
5570 {
5571 	const char *ct_path = ct->path;
5572 	unsigned char status;
5573 
5574 	if (status_cb == NULL) /* no commit progress output desired */
5575 		return NULL;
5576 
5577 	while (ct_path[0] == '/')
5578 		ct_path++;
5579 
5580 	if (ct->staged_status != GOT_STATUS_NO_CHANGE)
5581 		status = ct->staged_status;
5582 	else
5583 		status = ct->status;
5584 
5585 	return (*status_cb)(status_arg, status, GOT_STATUS_NO_CHANGE,
5586 	    ct_path, ct->blob_id, NULL, NULL, -1, NULL);
5587 }
5588 
5589 static const struct got_error *
5590 match_modified_subtree(int *modified, struct got_tree_entry *te,
5591     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
5592 {
5593 	const struct got_error *err = NULL;
5594 	struct got_pathlist_entry *pe;
5595 	char *te_path;
5596 
5597 	*modified = 0;
5598 
5599 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
5600 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
5601 	    te->name) == -1)
5602 		return got_error_from_errno("asprintf");
5603 
5604 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5605 		struct got_commitable *ct = pe->data;
5606 		*modified = got_path_is_child(ct->in_repo_path, te_path,
5607 		    strlen(te_path));
5608 		if (*modified)
5609 			break;
5610 	}
5611 
5612 	free(te_path);
5613 	return err;
5614 }
5615 
5616 static const struct got_error *
5617 match_deleted_or_modified_ct(struct got_commitable **ctp,
5618     struct got_tree_entry *te, const char *base_tree_path,
5619     struct got_pathlist_head *commitable_paths)
5620 {
5621 	const struct got_error *err = NULL;
5622 	struct got_pathlist_entry *pe;
5623 
5624 	*ctp = NULL;
5625 
5626 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5627 		struct got_commitable *ct = pe->data;
5628 		char *ct_name = NULL;
5629 		int path_matches;
5630 
5631 		if (ct->staged_status == GOT_STATUS_NO_CHANGE) {
5632 			if (ct->status != GOT_STATUS_MODIFY &&
5633 			    ct->status != GOT_STATUS_MODE_CHANGE &&
5634 			    ct->status != GOT_STATUS_DELETE &&
5635 			    ct->status != GOT_STATUS_CONFLICT)
5636 				continue;
5637 		} else {
5638 			if (ct->staged_status != GOT_STATUS_MODIFY &&
5639 			    ct->staged_status != GOT_STATUS_DELETE)
5640 				continue;
5641 		}
5642 
5643 		if (got_object_id_cmp(ct->base_blob_id, &te->id) != 0)
5644 			continue;
5645 
5646 		err = match_ct_parent_path(&path_matches, ct, base_tree_path);
5647 		if (err)
5648 			return err;
5649 		if (!path_matches)
5650 			continue;
5651 
5652 		err = got_path_basename(&ct_name, pe->path);
5653 		if (err)
5654 			return err;
5655 
5656 		if (strcmp(te->name, ct_name) != 0) {
5657 			free(ct_name);
5658 			continue;
5659 		}
5660 		free(ct_name);
5661 
5662 		*ctp = ct;
5663 		break;
5664 	}
5665 
5666 	return err;
5667 }
5668 
5669 static const struct got_error *
5670 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
5671     const char *child_path, const char *path_base_tree,
5672     struct got_pathlist_head *commitable_paths,
5673     got_worktree_status_cb status_cb, void *status_arg,
5674     struct got_repository *repo)
5675 {
5676 	const struct got_error *err = NULL;
5677 	struct got_tree_entry *new_te;
5678 	char *subtree_path;
5679 	struct got_object_id *id = NULL;
5680 	int nentries;
5681 
5682 	*new_tep = NULL;
5683 
5684 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
5685 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
5686 	    child_path) == -1)
5687 		return got_error_from_errno("asprintf");
5688 
5689 	new_te = calloc(1, sizeof(*new_te));
5690 	if (new_te == NULL)
5691 		return got_error_from_errno("calloc");
5692 	new_te->mode = S_IFDIR;
5693 
5694 	if (strlcpy(new_te->name, child_path, sizeof(new_te->name)) >=
5695 	    sizeof(new_te->name)) {
5696 		err = got_error(GOT_ERR_NO_SPACE);
5697 		goto done;
5698 	}
5699 	err = write_tree(&id, &nentries, NULL, subtree_path,
5700 	    commitable_paths, status_cb, status_arg, repo);
5701 	if (err) {
5702 		free(new_te);
5703 		goto done;
5704 	}
5705 	memcpy(&new_te->id, id, sizeof(new_te->id));
5706 done:
5707 	free(id);
5708 	free(subtree_path);
5709 	if (err == NULL)
5710 		*new_tep = new_te;
5711 	return err;
5712 }
5713 
5714 static const struct got_error *
5715 write_tree(struct got_object_id **new_tree_id, int *nentries,
5716     struct got_tree_object *base_tree, const char *path_base_tree,
5717     struct got_pathlist_head *commitable_paths,
5718     got_worktree_status_cb status_cb, void *status_arg,
5719     struct got_repository *repo)
5720 {
5721 	const struct got_error *err = NULL;
5722 	struct got_pathlist_head paths;
5723 	struct got_tree_entry *te, *new_te = NULL;
5724 	struct got_pathlist_entry *pe;
5725 
5726 	TAILQ_INIT(&paths);
5727 	*nentries = 0;
5728 
5729 	/* Insert, and recurse into, newly added entries first. */
5730 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5731 		struct got_commitable *ct = pe->data;
5732 		char *child_path = NULL, *slash;
5733 
5734 		if ((ct->status != GOT_STATUS_ADD &&
5735 		    ct->staged_status != GOT_STATUS_ADD) ||
5736 		    (ct->flags & GOT_COMMITABLE_ADDED))
5737 			continue;
5738 
5739 		if (!got_path_is_child(ct->in_repo_path, path_base_tree,
5740 		    strlen(path_base_tree)))
5741 			continue;
5742 
5743 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
5744 		    ct->in_repo_path);
5745 		if (err)
5746 			goto done;
5747 
5748 		slash = strchr(child_path, '/');
5749 		if (slash == NULL) {
5750 			err = alloc_added_blob_tree_entry(&new_te, ct);
5751 			if (err)
5752 				goto done;
5753 			err = report_ct_status(ct, status_cb, status_arg);
5754 			if (err)
5755 				goto done;
5756 			ct->flags |= GOT_COMMITABLE_ADDED;
5757 			err = insert_tree_entry(new_te, &paths);
5758 			if (err)
5759 				goto done;
5760 			(*nentries)++;
5761 		} else {
5762 			*slash = '\0'; /* trim trailing path components */
5763 			if (base_tree == NULL ||
5764 			    got_object_tree_find_entry(base_tree, child_path)
5765 			    == NULL) {
5766 				err = make_subtree_for_added_blob(&new_te,
5767 				    child_path, path_base_tree,
5768 				    commitable_paths, status_cb, status_arg,
5769 				    repo);
5770 				if (err)
5771 					goto done;
5772 				err = insert_tree_entry(new_te, &paths);
5773 				if (err)
5774 					goto done;
5775 				(*nentries)++;
5776 			}
5777 		}
5778 	}
5779 
5780 	if (base_tree) {
5781 		int i, nbase_entries;
5782 		/* Handle modified and deleted entries. */
5783 		nbase_entries = got_object_tree_get_nentries(base_tree);
5784 		for (i = 0; i < nbase_entries; i++) {
5785 			struct got_commitable *ct = NULL;
5786 
5787 			te = got_object_tree_get_entry(base_tree, i);
5788 			if (got_object_tree_entry_is_submodule(te)) {
5789 				/* Entry is a submodule; just copy it. */
5790 				err = got_object_tree_entry_dup(&new_te, te);
5791 				if (err)
5792 					goto done;
5793 				err = insert_tree_entry(new_te, &paths);
5794 				if (err)
5795 					goto done;
5796 				(*nentries)++;
5797 				continue;
5798 			}
5799 
5800 			if (S_ISDIR(te->mode)) {
5801 				int modified;
5802 				err = got_object_tree_entry_dup(&new_te, te);
5803 				if (err)
5804 					goto done;
5805 				err = match_modified_subtree(&modified, te,
5806 				    path_base_tree, commitable_paths);
5807 				if (err)
5808 					goto done;
5809 				/* Avoid recursion into unmodified subtrees. */
5810 				if (modified) {
5811 					struct got_object_id *new_id;
5812 					int nsubentries;
5813 					err = write_subtree(&new_id,
5814 					    &nsubentries, te,
5815 					    path_base_tree, commitable_paths,
5816 					    status_cb, status_arg, repo);
5817 					if (err)
5818 						goto done;
5819 					if (nsubentries == 0) {
5820 						/* All entries were deleted. */
5821 						free(new_id);
5822 						continue;
5823 					}
5824 					memcpy(&new_te->id, new_id,
5825 					    sizeof(new_te->id));
5826 					free(new_id);
5827 				}
5828 				err = insert_tree_entry(new_te, &paths);
5829 				if (err)
5830 					goto done;
5831 				(*nentries)++;
5832 				continue;
5833 			}
5834 
5835 			err = match_deleted_or_modified_ct(&ct, te,
5836 			    path_base_tree, commitable_paths);
5837 			if (err)
5838 				goto done;
5839 			if (ct) {
5840 				/* NB: Deleted entries get dropped here. */
5841 				if (ct->status == GOT_STATUS_MODIFY ||
5842 				    ct->status == GOT_STATUS_MODE_CHANGE ||
5843 				    ct->status == GOT_STATUS_CONFLICT ||
5844 				    ct->staged_status == GOT_STATUS_MODIFY) {
5845 					err = alloc_modified_blob_tree_entry(
5846 					    &new_te, te, ct);
5847 					if (err)
5848 						goto done;
5849 					err = insert_tree_entry(new_te, &paths);
5850 					if (err)
5851 						goto done;
5852 					(*nentries)++;
5853 				}
5854 				err = report_ct_status(ct, status_cb,
5855 				    status_arg);
5856 				if (err)
5857 					goto done;
5858 			} else {
5859 				/* Entry is unchanged; just copy it. */
5860 				err = got_object_tree_entry_dup(&new_te, te);
5861 				if (err)
5862 					goto done;
5863 				err = insert_tree_entry(new_te, &paths);
5864 				if (err)
5865 					goto done;
5866 				(*nentries)++;
5867 			}
5868 		}
5869 	}
5870 
5871 	/* Write new list of entries; deleted entries have been dropped. */
5872 	err = got_object_tree_create(new_tree_id, &paths, *nentries, repo);
5873 done:
5874 	got_pathlist_free(&paths, GOT_PATHLIST_FREE_NONE);
5875 	return err;
5876 }
5877 
5878 static const struct got_error *
5879 update_fileindex_after_commit(struct got_worktree *worktree,
5880     struct got_pathlist_head *commitable_paths,
5881     struct got_object_id *new_base_commit_id,
5882     struct got_fileindex *fileindex, int have_staged_files)
5883 {
5884 	const struct got_error *err = NULL;
5885 	struct got_pathlist_entry *pe;
5886 	char *relpath = NULL;
5887 
5888 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5889 		struct got_fileindex_entry *ie;
5890 		struct got_commitable *ct = pe->data;
5891 
5892 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
5893 
5894 		err = got_path_skip_common_ancestor(&relpath,
5895 		    worktree->root_path, ct->ondisk_path);
5896 		if (err)
5897 			goto done;
5898 
5899 		if (ie) {
5900 			if (ct->status == GOT_STATUS_DELETE ||
5901 			    ct->staged_status == GOT_STATUS_DELETE) {
5902 				got_fileindex_entry_remove(fileindex, ie);
5903 			} else if (ct->staged_status == GOT_STATUS_ADD ||
5904 			    ct->staged_status == GOT_STATUS_MODIFY) {
5905 				got_fileindex_entry_stage_set(ie,
5906 				    GOT_FILEIDX_STAGE_NONE);
5907 				got_fileindex_entry_staged_filetype_set(ie, 0);
5908 
5909 				err = got_fileindex_entry_update(ie,
5910 				    worktree->root_fd, relpath,
5911 				    ct->staged_blob_id->sha1,
5912 				    new_base_commit_id->sha1,
5913 				    !have_staged_files);
5914 			} else
5915 				err = got_fileindex_entry_update(ie,
5916 				    worktree->root_fd, relpath,
5917 				    ct->blob_id->sha1,
5918 				    new_base_commit_id->sha1,
5919 				    !have_staged_files);
5920 		} else {
5921 			err = got_fileindex_entry_alloc(&ie, pe->path);
5922 			if (err)
5923 				goto done;
5924 			err = got_fileindex_entry_update(ie,
5925 			    worktree->root_fd, relpath, ct->blob_id->sha1,
5926 			    new_base_commit_id->sha1, 1);
5927 			if (err) {
5928 				got_fileindex_entry_free(ie);
5929 				goto done;
5930 			}
5931 			err = got_fileindex_entry_add(fileindex, ie);
5932 			if (err) {
5933 				got_fileindex_entry_free(ie);
5934 				goto done;
5935 			}
5936 		}
5937 		free(relpath);
5938 		relpath = NULL;
5939 	}
5940 done:
5941 	free(relpath);
5942 	return err;
5943 }
5944 
5945 
5946 static const struct got_error *
5947 check_out_of_date(const char *in_repo_path, unsigned char status,
5948     unsigned char staged_status, struct got_object_id *base_blob_id,
5949     struct got_object_id *base_commit_id,
5950     struct got_object_id *head_commit_id, struct got_repository *repo,
5951     int ood_errcode)
5952 {
5953 	const struct got_error *err = NULL;
5954 	struct got_commit_object *commit = NULL;
5955 	struct got_object_id *id = NULL;
5956 
5957 	if (status != GOT_STATUS_ADD && staged_status != GOT_STATUS_ADD) {
5958 		/* Trivial case: base commit == head commit */
5959 		if (got_object_id_cmp(base_commit_id, head_commit_id) == 0)
5960 			return NULL;
5961 		/*
5962 		 * Ensure file content which local changes were based
5963 		 * on matches file content in the branch head.
5964 		 */
5965 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
5966 		if (err)
5967 			goto done;
5968 		err = got_object_id_by_path(&id, repo, commit, in_repo_path);
5969 		if (err) {
5970 			if (err->code == GOT_ERR_NO_TREE_ENTRY)
5971 				err = got_error(ood_errcode);
5972 			goto done;
5973 		} else if (got_object_id_cmp(id, base_blob_id) != 0)
5974 			err = got_error(ood_errcode);
5975 	} else {
5976 		/* Require that added files don't exist in the branch head. */
5977 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
5978 		if (err)
5979 			goto done;
5980 		err = got_object_id_by_path(&id, repo, commit, in_repo_path);
5981 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
5982 			goto done;
5983 		err = id ? got_error(ood_errcode) : NULL;
5984 	}
5985 done:
5986 	free(id);
5987 	if (commit)
5988 		got_object_commit_close(commit);
5989 	return err;
5990 }
5991 
5992 static const struct got_error *
5993 commit_worktree(struct got_object_id **new_commit_id,
5994     struct got_pathlist_head *commitable_paths,
5995     struct got_object_id *head_commit_id,
5996     struct got_object_id *parent_id2,
5997     struct got_worktree *worktree,
5998     const char *author, const char *committer, char *diff_path,
5999     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
6000     got_worktree_status_cb status_cb, void *status_arg,
6001     struct got_repository *repo)
6002 {
6003 	const struct got_error *err = NULL, *unlockerr = NULL;
6004 	struct got_pathlist_entry *pe;
6005 	const char *head_ref_name = NULL;
6006 	struct got_commit_object *head_commit = NULL;
6007 	struct got_reference *head_ref2 = NULL;
6008 	struct got_object_id *head_commit_id2 = NULL;
6009 	struct got_tree_object *head_tree = NULL;
6010 	struct got_object_id *new_tree_id = NULL;
6011 	int nentries, nparents = 0;
6012 	struct got_object_id_queue parent_ids;
6013 	struct got_object_qid *pid = NULL;
6014 	char *logmsg = NULL;
6015 	time_t timestamp;
6016 
6017 	*new_commit_id = NULL;
6018 
6019 	STAILQ_INIT(&parent_ids);
6020 
6021 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
6022 	if (err)
6023 		goto done;
6024 
6025 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
6026 	if (err)
6027 		goto done;
6028 
6029 	if (commit_msg_cb != NULL) {
6030 		err = commit_msg_cb(commitable_paths, diff_path,
6031 		    &logmsg, commit_arg);
6032 		if (err)
6033 			goto done;
6034 	}
6035 
6036 	if (logmsg == NULL || strlen(logmsg) == 0) {
6037 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
6038 		goto done;
6039 	}
6040 
6041 	/* Create blobs from added and modified files and record their IDs. */
6042 	TAILQ_FOREACH(pe, commitable_paths, entry) {
6043 		struct got_commitable *ct = pe->data;
6044 		char *ondisk_path;
6045 
6046 		/* Blobs for staged files already exist. */
6047 		if (ct->staged_status == GOT_STATUS_ADD ||
6048 		    ct->staged_status == GOT_STATUS_MODIFY)
6049 			continue;
6050 
6051 		if (ct->status != GOT_STATUS_ADD &&
6052 		    ct->status != GOT_STATUS_MODIFY &&
6053 		    ct->status != GOT_STATUS_MODE_CHANGE &&
6054 		    ct->status != GOT_STATUS_CONFLICT)
6055 			continue;
6056 
6057 		if (asprintf(&ondisk_path, "%s/%s",
6058 		    worktree->root_path, pe->path) == -1) {
6059 			err = got_error_from_errno("asprintf");
6060 			goto done;
6061 		}
6062 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
6063 		free(ondisk_path);
6064 		if (err)
6065 			goto done;
6066 	}
6067 
6068 	/* Recursively write new tree objects. */
6069 	err = write_tree(&new_tree_id, &nentries, head_tree, "/",
6070 	    commitable_paths, status_cb, status_arg, repo);
6071 	if (err)
6072 		goto done;
6073 
6074 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
6075 	if (err)
6076 		goto done;
6077 	STAILQ_INSERT_TAIL(&parent_ids, pid, entry);
6078 	nparents++;
6079 	if (parent_id2) {
6080 		err = got_object_qid_alloc(&pid, parent_id2);
6081 		if (err)
6082 			goto done;
6083 		STAILQ_INSERT_TAIL(&parent_ids, pid, entry);
6084 		nparents++;
6085 	}
6086 	timestamp = time(NULL);
6087 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
6088 	    nparents, author, timestamp, committer, timestamp, logmsg, repo);
6089 	if (logmsg != NULL)
6090 		free(logmsg);
6091 	if (err)
6092 		goto done;
6093 
6094 	/* Check if a concurrent commit to our branch has occurred. */
6095 	head_ref_name = got_worktree_get_head_ref_name(worktree);
6096 	if (head_ref_name == NULL) {
6097 		err = got_error_from_errno("got_worktree_get_head_ref_name");
6098 		goto done;
6099 	}
6100 	/* Lock the reference here to prevent concurrent modification. */
6101 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
6102 	if (err)
6103 		goto done;
6104 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
6105 	if (err)
6106 		goto done;
6107 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
6108 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
6109 		goto done;
6110 	}
6111 	/* Update branch head in repository. */
6112 	err = got_ref_change_ref(head_ref2, *new_commit_id);
6113 	if (err)
6114 		goto done;
6115 	err = got_ref_write(head_ref2, repo);
6116 	if (err)
6117 		goto done;
6118 
6119 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
6120 	if (err)
6121 		goto done;
6122 
6123 	err = ref_base_commit(worktree, repo);
6124 	if (err)
6125 		goto done;
6126 done:
6127 	got_object_id_queue_free(&parent_ids);
6128 	if (head_tree)
6129 		got_object_tree_close(head_tree);
6130 	if (head_commit)
6131 		got_object_commit_close(head_commit);
6132 	free(head_commit_id2);
6133 	if (head_ref2) {
6134 		unlockerr = got_ref_unlock(head_ref2);
6135 		if (unlockerr && err == NULL)
6136 			err = unlockerr;
6137 		got_ref_close(head_ref2);
6138 	}
6139 	return err;
6140 }
6141 
6142 static const struct got_error *
6143 check_path_is_commitable(const char *path,
6144     struct got_pathlist_head *commitable_paths)
6145 {
6146 	struct got_pathlist_entry *cpe = NULL;
6147 	size_t path_len = strlen(path);
6148 
6149 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
6150 		struct got_commitable *ct = cpe->data;
6151 		const char *ct_path = ct->path;
6152 
6153 		while (ct_path[0] == '/')
6154 			ct_path++;
6155 
6156 		if (strcmp(path, ct_path) == 0 ||
6157 		    got_path_is_child(ct_path, path, path_len))
6158 			break;
6159 	}
6160 
6161 	if (cpe == NULL)
6162 		return got_error_path(path, GOT_ERR_BAD_PATH);
6163 
6164 	return NULL;
6165 }
6166 
6167 static const struct got_error *
6168 check_staged_file(void *arg, struct got_fileindex_entry *ie)
6169 {
6170 	int *have_staged_files = arg;
6171 
6172 	if (got_fileindex_entry_stage_get(ie) != GOT_FILEIDX_STAGE_NONE) {
6173 		*have_staged_files = 1;
6174 		return got_error(GOT_ERR_CANCELLED);
6175 	}
6176 
6177 	return NULL;
6178 }
6179 
6180 static const struct got_error *
6181 check_non_staged_files(struct got_fileindex *fileindex,
6182     struct got_pathlist_head *paths)
6183 {
6184 	struct got_pathlist_entry *pe;
6185 	struct got_fileindex_entry *ie;
6186 
6187 	TAILQ_FOREACH(pe, paths, entry) {
6188 		if (pe->path[0] == '\0')
6189 			continue;
6190 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
6191 		if (ie == NULL)
6192 			return got_error_path(pe->path, GOT_ERR_BAD_PATH);
6193 		if (got_fileindex_entry_stage_get(ie) == GOT_FILEIDX_STAGE_NONE)
6194 			return got_error_path(pe->path,
6195 			    GOT_ERR_FILE_NOT_STAGED);
6196 	}
6197 
6198 	return NULL;
6199 }
6200 
6201 const struct got_error *
6202 got_worktree_commit(struct got_object_id **new_commit_id,
6203     struct got_worktree *worktree, struct got_pathlist_head *paths,
6204     const char *author, const char *committer, int allow_bad_symlinks,
6205     int show_diff, int commit_conflicts,
6206     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
6207     got_worktree_status_cb status_cb, void *status_arg,
6208     struct got_repository *repo)
6209 {
6210 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
6211 	struct got_fileindex *fileindex = NULL;
6212 	char *fileindex_path = NULL;
6213 	struct got_pathlist_head commitable_paths;
6214 	struct collect_commitables_arg cc_arg;
6215 	struct got_pathlist_entry *pe;
6216 	struct got_reference *head_ref = NULL;
6217 	struct got_object_id *head_commit_id = NULL;
6218 	char *diff_path = NULL;
6219 	int have_staged_files = 0;
6220 
6221 	*new_commit_id = NULL;
6222 
6223 	memset(&cc_arg, 0, sizeof(cc_arg));
6224 	TAILQ_INIT(&commitable_paths);
6225 
6226 	err = lock_worktree(worktree, LOCK_EX);
6227 	if (err)
6228 		goto done;
6229 
6230 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
6231 	if (err)
6232 		goto done;
6233 
6234 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
6235 	if (err)
6236 		goto done;
6237 
6238 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
6239 	if (err)
6240 		goto done;
6241 
6242 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
6243 	    &have_staged_files);
6244 	if (err && err->code != GOT_ERR_CANCELLED)
6245 		goto done;
6246 	if (have_staged_files) {
6247 		err = check_non_staged_files(fileindex, paths);
6248 		if (err)
6249 			goto done;
6250 	}
6251 
6252 	cc_arg.commitable_paths = &commitable_paths;
6253 	cc_arg.worktree = worktree;
6254 	cc_arg.fileindex = fileindex;
6255 	cc_arg.repo = repo;
6256 	cc_arg.have_staged_files = have_staged_files;
6257 	cc_arg.allow_bad_symlinks = allow_bad_symlinks;
6258 	cc_arg.diff_header_shown = 0;
6259 	cc_arg.commit_conflicts = commit_conflicts;
6260 	if (show_diff) {
6261 		err = got_opentemp_named(&diff_path, &cc_arg.diff_outfile,
6262 		    GOT_TMPDIR_STR "/got", ".diff");
6263 		if (err)
6264 			goto done;
6265 		cc_arg.f1 = got_opentemp();
6266 		if (cc_arg.f1 == NULL) {
6267 			err = got_error_from_errno("got_opentemp");
6268 			goto done;
6269 		}
6270 		cc_arg.f2 = got_opentemp();
6271 		if (cc_arg.f2 == NULL) {
6272 			err = got_error_from_errno("got_opentemp");
6273 			goto done;
6274 		}
6275 	}
6276 
6277 	TAILQ_FOREACH(pe, paths, entry) {
6278 		err = worktree_status(worktree, pe->path, fileindex, repo,
6279 		    collect_commitables, &cc_arg, NULL, NULL, 0, 0);
6280 		if (err)
6281 			goto done;
6282 	}
6283 
6284 	if (show_diff) {
6285 		if (fflush(cc_arg.diff_outfile) == EOF) {
6286 			err = got_error_from_errno("fflush");
6287 			goto done;
6288 		}
6289 	}
6290 
6291 	if (TAILQ_EMPTY(&commitable_paths)) {
6292 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
6293 		goto done;
6294 	}
6295 
6296 	TAILQ_FOREACH(pe, paths, entry) {
6297 		err = check_path_is_commitable(pe->path, &commitable_paths);
6298 		if (err)
6299 			goto done;
6300 	}
6301 
6302 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
6303 		struct got_commitable *ct = pe->data;
6304 		const char *ct_path = ct->in_repo_path;
6305 
6306 		while (ct_path[0] == '/')
6307 			ct_path++;
6308 		err = check_out_of_date(ct_path, ct->status,
6309 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
6310 		    head_commit_id, repo, GOT_ERR_COMMIT_OUT_OF_DATE);
6311 		if (err)
6312 			goto done;
6313 
6314 	}
6315 
6316 	err = commit_worktree(new_commit_id, &commitable_paths,
6317 	    head_commit_id, NULL, worktree, author, committer,
6318 	    (diff_path && cc_arg.diff_header_shown) ? diff_path : NULL,
6319 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
6320 	if (err)
6321 		goto done;
6322 
6323 	err = update_fileindex_after_commit(worktree, &commitable_paths,
6324 	    *new_commit_id, fileindex, have_staged_files);
6325 	sync_err = sync_fileindex(fileindex, fileindex_path);
6326 	if (sync_err && err == NULL)
6327 		err = sync_err;
6328 done:
6329 	if (fileindex)
6330 		got_fileindex_free(fileindex);
6331 	free(fileindex_path);
6332 	unlockerr = lock_worktree(worktree, LOCK_SH);
6333 	if (unlockerr && err == NULL)
6334 		err = unlockerr;
6335 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
6336 		struct got_commitable *ct = pe->data;
6337 
6338 		free_commitable(ct);
6339 	}
6340 	got_pathlist_free(&commitable_paths, GOT_PATHLIST_FREE_NONE);
6341 	if (diff_path && unlink(diff_path) == -1 && err == NULL)
6342 		err = got_error_from_errno2("unlink", diff_path);
6343 	free(diff_path);
6344 	if (cc_arg.diff_outfile && fclose(cc_arg.diff_outfile) == EOF &&
6345 	    err == NULL)
6346 		err = got_error_from_errno("fclose");
6347 	return err;
6348 }
6349 
6350 const char *
6351 got_commitable_get_path(struct got_commitable *ct)
6352 {
6353 	return ct->path;
6354 }
6355 
6356 unsigned int
6357 got_commitable_get_status(struct got_commitable *ct)
6358 {
6359 	return ct->status;
6360 }
6361 
6362 struct check_rebase_ok_arg {
6363 	struct got_worktree *worktree;
6364 	struct got_repository *repo;
6365 };
6366 
6367 static const struct got_error *
6368 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
6369 {
6370 	const struct got_error *err = NULL;
6371 	struct check_rebase_ok_arg *a = arg;
6372 	unsigned char status;
6373 	struct stat sb;
6374 	char *ondisk_path;
6375 
6376 	/* Reject rebase of a work tree with mixed base commits. */
6377 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
6378 	    SHA1_DIGEST_LENGTH))
6379 		return got_error(GOT_ERR_MIXED_COMMITS);
6380 
6381 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
6382 	    == -1)
6383 		return got_error_from_errno("asprintf");
6384 
6385 	/* Reject rebase of a work tree with modified or staged files. */
6386 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
6387 	free(ondisk_path);
6388 	if (err)
6389 		return err;
6390 
6391 	if (status != GOT_STATUS_NO_CHANGE)
6392 		return got_error(GOT_ERR_MODIFIED);
6393 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
6394 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
6395 
6396 	return NULL;
6397 }
6398 
6399 const struct got_error *
6400 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
6401     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
6402     struct got_worktree *worktree, struct got_reference *branch,
6403     struct got_repository *repo)
6404 {
6405 	const struct got_error *err = NULL;
6406 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
6407 	char *branch_ref_name = NULL;
6408 	char *fileindex_path = NULL;
6409 	struct check_rebase_ok_arg ok_arg;
6410 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
6411 	struct got_object_id *wt_branch_tip = NULL;
6412 
6413 	*new_base_branch_ref = NULL;
6414 	*tmp_branch = NULL;
6415 	*fileindex = NULL;
6416 
6417 	err = lock_worktree(worktree, LOCK_EX);
6418 	if (err)
6419 		return err;
6420 
6421 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6422 	if (err)
6423 		goto done;
6424 
6425 	ok_arg.worktree = worktree;
6426 	ok_arg.repo = repo;
6427 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
6428 	    &ok_arg);
6429 	if (err)
6430 		goto done;
6431 
6432 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6433 	if (err)
6434 		goto done;
6435 
6436 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6437 	if (err)
6438 		goto done;
6439 
6440 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6441 	if (err)
6442 		goto done;
6443 
6444 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
6445 	    0);
6446 	if (err)
6447 		goto done;
6448 
6449 	err = got_ref_resolve(&wt_branch_tip, repo, wt_branch);
6450 	if (err)
6451 		goto done;
6452 	if (got_object_id_cmp(worktree->base_commit_id, wt_branch_tip) != 0) {
6453 		err = got_error(GOT_ERR_REBASE_OUT_OF_DATE);
6454 		goto done;
6455 	}
6456 
6457 	err = got_ref_alloc_symref(new_base_branch_ref,
6458 	    new_base_branch_ref_name, wt_branch);
6459 	if (err)
6460 		goto done;
6461 	err = got_ref_write(*new_base_branch_ref, repo);
6462 	if (err)
6463 		goto done;
6464 
6465 	/* TODO Lock original branch's ref while rebasing? */
6466 
6467 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
6468 	if (err)
6469 		goto done;
6470 
6471 	err = got_ref_write(branch_ref, repo);
6472 	if (err)
6473 		goto done;
6474 
6475 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
6476 	    worktree->base_commit_id);
6477 	if (err)
6478 		goto done;
6479 	err = got_ref_write(*tmp_branch, repo);
6480 	if (err)
6481 		goto done;
6482 
6483 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
6484 	if (err)
6485 		goto done;
6486 done:
6487 	free(fileindex_path);
6488 	free(tmp_branch_name);
6489 	free(new_base_branch_ref_name);
6490 	free(branch_ref_name);
6491 	if (branch_ref)
6492 		got_ref_close(branch_ref);
6493 	if (wt_branch)
6494 		got_ref_close(wt_branch);
6495 	free(wt_branch_tip);
6496 	if (err) {
6497 		if (*new_base_branch_ref) {
6498 			got_ref_close(*new_base_branch_ref);
6499 			*new_base_branch_ref = NULL;
6500 		}
6501 		if (*tmp_branch) {
6502 			got_ref_close(*tmp_branch);
6503 			*tmp_branch = NULL;
6504 		}
6505 		if (*fileindex) {
6506 			got_fileindex_free(*fileindex);
6507 			*fileindex = NULL;
6508 		}
6509 		lock_worktree(worktree, LOCK_SH);
6510 	}
6511 	return err;
6512 }
6513 
6514 const struct got_error *
6515 got_worktree_rebase_continue(struct got_object_id **commit_id,
6516     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
6517     struct got_reference **branch, struct got_fileindex **fileindex,
6518     struct got_worktree *worktree, struct got_repository *repo)
6519 {
6520 	const struct got_error *err;
6521 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
6522 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
6523 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
6524 	char *fileindex_path = NULL;
6525 	int have_staged_files = 0;
6526 
6527 	*commit_id = NULL;
6528 	*new_base_branch = NULL;
6529 	*tmp_branch = NULL;
6530 	*branch = NULL;
6531 	*fileindex = NULL;
6532 
6533 	err = lock_worktree(worktree, LOCK_EX);
6534 	if (err)
6535 		return err;
6536 
6537 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6538 	if (err)
6539 		goto done;
6540 
6541 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
6542 	    &have_staged_files);
6543 	if (err && err->code != GOT_ERR_CANCELLED)
6544 		goto done;
6545 	if (have_staged_files) {
6546 		err = got_error(GOT_ERR_STAGED_PATHS);
6547 		goto done;
6548 	}
6549 
6550 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6551 	if (err)
6552 		goto done;
6553 
6554 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6555 	if (err)
6556 		goto done;
6557 
6558 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6559 	if (err)
6560 		goto done;
6561 
6562 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6563 	if (err)
6564 		goto done;
6565 
6566 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
6567 	if (err)
6568 		goto done;
6569 
6570 	err = got_ref_open(branch, repo,
6571 	    got_ref_get_symref_target(branch_ref), 0);
6572 	if (err)
6573 		goto done;
6574 
6575 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6576 	if (err)
6577 		goto done;
6578 
6579 	err = got_ref_resolve(commit_id, repo, commit_ref);
6580 	if (err)
6581 		goto done;
6582 
6583 	err = got_ref_open(new_base_branch, repo,
6584 	    new_base_branch_ref_name, 0);
6585 	if (err)
6586 		goto done;
6587 
6588 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
6589 	if (err)
6590 		goto done;
6591 done:
6592 	free(commit_ref_name);
6593 	free(branch_ref_name);
6594 	free(fileindex_path);
6595 	if (commit_ref)
6596 		got_ref_close(commit_ref);
6597 	if (branch_ref)
6598 		got_ref_close(branch_ref);
6599 	if (err) {
6600 		free(*commit_id);
6601 		*commit_id = NULL;
6602 		if (*tmp_branch) {
6603 			got_ref_close(*tmp_branch);
6604 			*tmp_branch = NULL;
6605 		}
6606 		if (*new_base_branch) {
6607 			got_ref_close(*new_base_branch);
6608 			*new_base_branch = NULL;
6609 		}
6610 		if (*branch) {
6611 			got_ref_close(*branch);
6612 			*branch = NULL;
6613 		}
6614 		if (*fileindex) {
6615 			got_fileindex_free(*fileindex);
6616 			*fileindex = NULL;
6617 		}
6618 		lock_worktree(worktree, LOCK_SH);
6619 	}
6620 	return err;
6621 }
6622 
6623 const struct got_error *
6624 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
6625 {
6626 	const struct got_error *err;
6627 	char *tmp_branch_name = NULL;
6628 
6629 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6630 	if (err)
6631 		return err;
6632 
6633 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
6634 	free(tmp_branch_name);
6635 	return NULL;
6636 }
6637 
6638 static const struct got_error *
6639 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
6640     const char *diff_path, char **logmsg, void *arg)
6641 {
6642 	*logmsg = arg;
6643 	return NULL;
6644 }
6645 
6646 static const struct got_error *
6647 rebase_status(void *arg, unsigned char status, unsigned char staged_status,
6648     const char *path, struct got_object_id *blob_id,
6649     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
6650     int dirfd, const char *de_name)
6651 {
6652 	return NULL;
6653 }
6654 
6655 struct collect_merged_paths_arg {
6656 	got_worktree_checkout_cb progress_cb;
6657 	void *progress_arg;
6658 	struct got_pathlist_head *merged_paths;
6659 };
6660 
6661 static const struct got_error *
6662 collect_merged_paths(void *arg, unsigned char status, const char *path)
6663 {
6664 	const struct got_error *err;
6665 	struct collect_merged_paths_arg *a = arg;
6666 	char *p;
6667 	struct got_pathlist_entry *new;
6668 
6669 	err = (*a->progress_cb)(a->progress_arg, status, path);
6670 	if (err)
6671 		return err;
6672 
6673 	if (status != GOT_STATUS_MERGE &&
6674 	    status != GOT_STATUS_ADD &&
6675 	    status != GOT_STATUS_DELETE &&
6676 	    status != GOT_STATUS_CONFLICT)
6677 		return NULL;
6678 
6679 	p = strdup(path);
6680 	if (p == NULL)
6681 		return got_error_from_errno("strdup");
6682 
6683 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
6684 	if (err || new == NULL)
6685 		free(p);
6686 	return err;
6687 }
6688 
6689 static const struct got_error *
6690 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
6691     int is_rebase, struct got_repository *repo)
6692 {
6693 	const struct got_error *err;
6694 	struct got_reference *commit_ref = NULL;
6695 
6696 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6697 	if (err) {
6698 		if (err->code != GOT_ERR_NOT_REF)
6699 			goto done;
6700 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
6701 		if (err)
6702 			goto done;
6703 		err = got_ref_write(commit_ref, repo);
6704 		if (err)
6705 			goto done;
6706 	} else if (is_rebase) {
6707 		struct got_object_id *stored_id;
6708 		int cmp;
6709 
6710 		err = got_ref_resolve(&stored_id, repo, commit_ref);
6711 		if (err)
6712 			goto done;
6713 		cmp = got_object_id_cmp(commit_id, stored_id);
6714 		free(stored_id);
6715 		if (cmp != 0) {
6716 			err = got_error(GOT_ERR_REBASE_COMMITID);
6717 			goto done;
6718 		}
6719 	}
6720 done:
6721 	if (commit_ref)
6722 		got_ref_close(commit_ref);
6723 	return err;
6724 }
6725 
6726 static const struct got_error *
6727 rebase_merge_files(struct got_pathlist_head *merged_paths,
6728     const char *commit_ref_name, struct got_worktree *worktree,
6729     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
6730     struct got_object_id *commit_id, struct got_repository *repo,
6731     got_worktree_checkout_cb progress_cb, void *progress_arg,
6732     got_cancel_cb cancel_cb, void *cancel_arg)
6733 {
6734 	const struct got_error *err;
6735 	struct got_reference *commit_ref = NULL;
6736 	struct collect_merged_paths_arg cmp_arg;
6737 	char *fileindex_path;
6738 
6739 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6740 
6741 	err = get_fileindex_path(&fileindex_path, worktree);
6742 	if (err)
6743 		return err;
6744 
6745 	cmp_arg.progress_cb = progress_cb;
6746 	cmp_arg.progress_arg = progress_arg;
6747 	cmp_arg.merged_paths = merged_paths;
6748 	err = merge_files(worktree, fileindex, fileindex_path,
6749 	    parent_commit_id, commit_id, repo, collect_merged_paths,
6750 	    &cmp_arg, cancel_cb, cancel_arg);
6751 	if (commit_ref)
6752 		got_ref_close(commit_ref);
6753 	return err;
6754 }
6755 
6756 const struct got_error *
6757 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
6758     struct got_worktree *worktree, struct got_fileindex *fileindex,
6759     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6760     struct got_repository *repo,
6761     got_worktree_checkout_cb progress_cb, void *progress_arg,
6762     got_cancel_cb cancel_cb, void *cancel_arg)
6763 {
6764 	const struct got_error *err;
6765 	char *commit_ref_name;
6766 
6767 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6768 	if (err)
6769 		return err;
6770 
6771 	err = store_commit_id(commit_ref_name, commit_id, 1, repo);
6772 	if (err)
6773 		goto done;
6774 
6775 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6776 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6777 	    progress_arg, cancel_cb, cancel_arg);
6778 done:
6779 	free(commit_ref_name);
6780 	return err;
6781 }
6782 
6783 const struct got_error *
6784 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
6785     struct got_worktree *worktree, struct got_fileindex *fileindex,
6786     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6787     struct got_repository *repo,
6788     got_worktree_checkout_cb progress_cb, void *progress_arg,
6789     got_cancel_cb cancel_cb, void *cancel_arg)
6790 {
6791 	const struct got_error *err;
6792 	char *commit_ref_name;
6793 
6794 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6795 	if (err)
6796 		return err;
6797 
6798 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
6799 	if (err)
6800 		goto done;
6801 
6802 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6803 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6804 	    progress_arg, cancel_cb, cancel_arg);
6805 done:
6806 	free(commit_ref_name);
6807 	return err;
6808 }
6809 
6810 static const struct got_error *
6811 rebase_commit(struct got_object_id **new_commit_id,
6812     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
6813     struct got_worktree *worktree, struct got_fileindex *fileindex,
6814     struct got_reference *tmp_branch, const char *committer,
6815     struct got_commit_object *orig_commit, const char *new_logmsg,
6816     int allow_conflict, struct got_repository *repo)
6817 {
6818 	const struct got_error *err, *sync_err;
6819 	struct got_pathlist_head commitable_paths;
6820 	struct collect_commitables_arg cc_arg;
6821 	char *fileindex_path = NULL;
6822 	struct got_reference *head_ref = NULL;
6823 	struct got_object_id *head_commit_id = NULL;
6824 	char *logmsg = NULL;
6825 
6826 	memset(&cc_arg, 0, sizeof(cc_arg));
6827 	TAILQ_INIT(&commitable_paths);
6828 	*new_commit_id = NULL;
6829 
6830 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6831 
6832 	err = get_fileindex_path(&fileindex_path, worktree);
6833 	if (err)
6834 		return err;
6835 
6836 	cc_arg.commitable_paths = &commitable_paths;
6837 	cc_arg.worktree = worktree;
6838 	cc_arg.repo = repo;
6839 	cc_arg.have_staged_files = 0;
6840 	cc_arg.commit_conflicts = allow_conflict;
6841 	/*
6842 	 * If possible get the status of individual files directly to
6843 	 * avoid crawling the entire work tree once per rebased commit.
6844 	 *
6845 	 * Ideally, merged_paths would contain a list of commitables
6846 	 * we could use so we could skip worktree_status() entirely.
6847 	 * However, we would then need carefully keep track of cumulative
6848 	 * effects of operations such as file additions and deletions
6849 	 * in 'got histedit -f' (folding multiple commits into one),
6850 	 * and this extra complexity is not really worth it.
6851 	 */
6852 	if (merged_paths) {
6853 		struct got_pathlist_entry *pe;
6854 		TAILQ_FOREACH(pe, merged_paths, entry) {
6855 			err = worktree_status(worktree, pe->path, fileindex,
6856 			    repo, collect_commitables, &cc_arg, NULL, NULL, 1,
6857 			    0);
6858 			if (err)
6859 				goto done;
6860 		}
6861 	} else {
6862 		err = worktree_status(worktree, "", fileindex, repo,
6863 		    collect_commitables, &cc_arg, NULL, NULL, 1, 0);
6864 		if (err)
6865 			goto done;
6866 	}
6867 
6868 	if (TAILQ_EMPTY(&commitable_paths)) {
6869 		/* No-op change; commit will be elided. */
6870 		err = got_ref_delete(commit_ref, repo);
6871 		if (err)
6872 			goto done;
6873 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
6874 		goto done;
6875 	}
6876 
6877 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
6878 	if (err)
6879 		goto done;
6880 
6881 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
6882 	if (err)
6883 		goto done;
6884 
6885 	if (new_logmsg) {
6886 		logmsg = strdup(new_logmsg);
6887 		if (logmsg == NULL) {
6888 			err = got_error_from_errno("strdup");
6889 			goto done;
6890 		}
6891 	} else {
6892 		err = got_object_commit_get_logmsg(&logmsg, orig_commit);
6893 		if (err)
6894 			goto done;
6895 	}
6896 
6897 	/* NB: commit_worktree will call free(logmsg) */
6898 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
6899 	    NULL, worktree, got_object_commit_get_author(orig_commit),
6900 	    committer ? committer :
6901 	    got_object_commit_get_committer(orig_commit), NULL,
6902 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
6903 	if (err)
6904 		goto done;
6905 
6906 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
6907 	if (err)
6908 		goto done;
6909 
6910 	err = got_ref_delete(commit_ref, repo);
6911 	if (err)
6912 		goto done;
6913 
6914 	err = update_fileindex_after_commit(worktree, &commitable_paths,
6915 	    *new_commit_id, fileindex, 0);
6916 	sync_err = sync_fileindex(fileindex, fileindex_path);
6917 	if (sync_err && err == NULL)
6918 		err = sync_err;
6919 done:
6920 	free(fileindex_path);
6921 	free(head_commit_id);
6922 	if (head_ref)
6923 		got_ref_close(head_ref);
6924 	if (err) {
6925 		free(*new_commit_id);
6926 		*new_commit_id = NULL;
6927 	}
6928 	return err;
6929 }
6930 
6931 const struct got_error *
6932 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
6933     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6934     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6935     const char *committer, struct got_commit_object *orig_commit,
6936     struct got_object_id *orig_commit_id, int allow_conflict,
6937     struct got_repository *repo)
6938 {
6939 	const struct got_error *err;
6940 	char *commit_ref_name;
6941 	struct got_reference *commit_ref = NULL;
6942 	struct got_object_id *commit_id = NULL;
6943 
6944 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6945 	if (err)
6946 		return err;
6947 
6948 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6949 	if (err)
6950 		goto done;
6951 	err = got_ref_resolve(&commit_id, repo, commit_ref);
6952 	if (err)
6953 		goto done;
6954 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
6955 		err = got_error(GOT_ERR_REBASE_COMMITID);
6956 		goto done;
6957 	}
6958 
6959 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6960 	    worktree, fileindex, tmp_branch, committer, orig_commit,
6961 	    NULL, allow_conflict, repo);
6962 done:
6963 	if (commit_ref)
6964 		got_ref_close(commit_ref);
6965 	free(commit_ref_name);
6966 	free(commit_id);
6967 	return err;
6968 }
6969 
6970 const struct got_error *
6971 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
6972     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6973     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6974     const char *committer, struct got_commit_object *orig_commit,
6975     struct got_object_id *orig_commit_id, const char *new_logmsg,
6976     int allow_conflict, struct got_repository *repo)
6977 {
6978 	const struct got_error *err;
6979 	char *commit_ref_name;
6980 	struct got_reference *commit_ref = NULL;
6981 
6982 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6983 	if (err)
6984 		return err;
6985 
6986 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6987 	if (err)
6988 		goto done;
6989 
6990 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6991 	    worktree, fileindex, tmp_branch, committer, orig_commit,
6992 	    new_logmsg, allow_conflict, repo);
6993 done:
6994 	if (commit_ref)
6995 		got_ref_close(commit_ref);
6996 	free(commit_ref_name);
6997 	return err;
6998 }
6999 
7000 const struct got_error *
7001 got_worktree_rebase_postpone(struct got_worktree *worktree,
7002     struct got_fileindex *fileindex)
7003 {
7004 	if (fileindex)
7005 		got_fileindex_free(fileindex);
7006 	return lock_worktree(worktree, LOCK_SH);
7007 }
7008 
7009 static const struct got_error *
7010 delete_ref(const char *name, struct got_repository *repo)
7011 {
7012 	const struct got_error *err;
7013 	struct got_reference *ref;
7014 
7015 	err = got_ref_open(&ref, repo, name, 0);
7016 	if (err) {
7017 		if (err->code == GOT_ERR_NOT_REF)
7018 			return NULL;
7019 		return err;
7020 	}
7021 
7022 	err = got_ref_delete(ref, repo);
7023 	got_ref_close(ref);
7024 	return err;
7025 }
7026 
7027 static const struct got_error *
7028 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
7029 {
7030 	const struct got_error *err;
7031 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
7032 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
7033 
7034 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
7035 	if (err)
7036 		goto done;
7037 	err = delete_ref(tmp_branch_name, repo);
7038 	if (err)
7039 		goto done;
7040 
7041 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
7042 	if (err)
7043 		goto done;
7044 	err = delete_ref(new_base_branch_ref_name, repo);
7045 	if (err)
7046 		goto done;
7047 
7048 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
7049 	if (err)
7050 		goto done;
7051 	err = delete_ref(branch_ref_name, repo);
7052 	if (err)
7053 		goto done;
7054 
7055 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
7056 	if (err)
7057 		goto done;
7058 	err = delete_ref(commit_ref_name, repo);
7059 	if (err)
7060 		goto done;
7061 
7062 done:
7063 	free(tmp_branch_name);
7064 	free(new_base_branch_ref_name);
7065 	free(branch_ref_name);
7066 	free(commit_ref_name);
7067 	return err;
7068 }
7069 
7070 static const struct got_error *
7071 create_backup_ref(const char *backup_ref_prefix, struct got_reference *branch,
7072     struct got_object_id *new_commit_id, struct got_repository *repo)
7073 {
7074 	const struct got_error *err;
7075 	struct got_reference *ref = NULL;
7076 	struct got_object_id *old_commit_id = NULL;
7077 	const char *branch_name = NULL;
7078 	char *new_id_str = NULL;
7079 	char *refname = NULL;
7080 
7081 	branch_name = got_ref_get_name(branch);
7082 	if (strncmp(branch_name, "refs/heads/", 11) != 0)
7083 		return got_error(GOT_ERR_BAD_REF_NAME); /* should not happen */
7084 	branch_name += 11;
7085 
7086 	err = got_object_id_str(&new_id_str, new_commit_id);
7087 	if (err)
7088 		return err;
7089 
7090 	if (asprintf(&refname, "%s/%s/%s", backup_ref_prefix, branch_name,
7091 	    new_id_str) == -1) {
7092 		err = got_error_from_errno("asprintf");
7093 		goto done;
7094 	}
7095 
7096 	err = got_ref_resolve(&old_commit_id, repo, branch);
7097 	if (err)
7098 		goto done;
7099 
7100 	err = got_ref_alloc(&ref, refname, old_commit_id);
7101 	if (err)
7102 		goto done;
7103 
7104 	err = got_ref_write(ref, repo);
7105 done:
7106 	free(new_id_str);
7107 	free(refname);
7108 	free(old_commit_id);
7109 	if (ref)
7110 		got_ref_close(ref);
7111 	return err;
7112 }
7113 
7114 const struct got_error *
7115 got_worktree_rebase_complete(struct got_worktree *worktree,
7116     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
7117     struct got_reference *rebased_branch, struct got_repository *repo,
7118     int create_backup)
7119 {
7120 	const struct got_error *err, *unlockerr, *sync_err;
7121 	struct got_object_id *new_head_commit_id = NULL;
7122 	char *fileindex_path = NULL;
7123 
7124 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
7125 	if (err)
7126 		return err;
7127 
7128 	if (create_backup) {
7129 		err = create_backup_ref(GOT_WORKTREE_REBASE_BACKUP_REF_PREFIX,
7130 		    rebased_branch, new_head_commit_id, repo);
7131 		if (err)
7132 			goto done;
7133 	}
7134 
7135 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
7136 	if (err)
7137 		goto done;
7138 
7139 	err = got_ref_write(rebased_branch, repo);
7140 	if (err)
7141 		goto done;
7142 
7143 	err = got_worktree_set_head_ref(worktree, rebased_branch);
7144 	if (err)
7145 		goto done;
7146 
7147 	err = delete_rebase_refs(worktree, repo);
7148 	if (err)
7149 		goto done;
7150 
7151 	err = get_fileindex_path(&fileindex_path, worktree);
7152 	if (err)
7153 		goto done;
7154 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7155 	sync_err = sync_fileindex(fileindex, fileindex_path);
7156 	if (sync_err && err == NULL)
7157 		err = sync_err;
7158 done:
7159 	got_fileindex_free(fileindex);
7160 	free(fileindex_path);
7161 	free(new_head_commit_id);
7162 	unlockerr = lock_worktree(worktree, LOCK_SH);
7163 	if (unlockerr && err == NULL)
7164 		err = unlockerr;
7165 	return err;
7166 }
7167 
7168 const struct got_error *
7169 got_worktree_rebase_abort(struct got_worktree *worktree,
7170     struct got_fileindex *fileindex, struct got_repository *repo,
7171     struct got_reference *new_base_branch,
7172     got_worktree_checkout_cb progress_cb, void *progress_arg)
7173 {
7174 	const struct got_error *err, *unlockerr, *sync_err;
7175 	struct got_reference *resolved = NULL;
7176 	struct got_object_id *commit_id = NULL;
7177 	struct got_commit_object *commit = NULL;
7178 	char *fileindex_path = NULL;
7179 	struct revert_file_args rfa;
7180 	struct got_object_id *tree_id = NULL;
7181 
7182 	err = lock_worktree(worktree, LOCK_EX);
7183 	if (err)
7184 		return err;
7185 
7186 	err = got_object_open_as_commit(&commit, repo,
7187 	    worktree->base_commit_id);
7188 	if (err)
7189 		goto done;
7190 
7191 	err = got_ref_open(&resolved, repo,
7192 	    got_ref_get_symref_target(new_base_branch), 0);
7193 	if (err)
7194 		goto done;
7195 
7196 	err = got_worktree_set_head_ref(worktree, resolved);
7197 	if (err)
7198 		goto done;
7199 
7200 	/*
7201 	 * XXX commits to the base branch could have happened while
7202 	 * we were busy rebasing; should we store the original commit ID
7203 	 * when rebase begins and read it back here?
7204 	 */
7205 	err = got_ref_resolve(&commit_id, repo, resolved);
7206 	if (err)
7207 		goto done;
7208 
7209 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
7210 	if (err)
7211 		goto done;
7212 
7213 	err = got_object_id_by_path(&tree_id, repo, commit,
7214 	    worktree->path_prefix);
7215 	if (err)
7216 		goto done;
7217 
7218 	err = delete_rebase_refs(worktree, repo);
7219 	if (err)
7220 		goto done;
7221 
7222 	err = get_fileindex_path(&fileindex_path, worktree);
7223 	if (err)
7224 		goto done;
7225 
7226 	rfa.worktree = worktree;
7227 	rfa.fileindex = fileindex;
7228 	rfa.progress_cb = progress_cb;
7229 	rfa.progress_arg = progress_arg;
7230 	rfa.patch_cb = NULL;
7231 	rfa.patch_arg = NULL;
7232 	rfa.repo = repo;
7233 	rfa.unlink_added_files = 0;
7234 	err = worktree_status(worktree, "", fileindex, repo,
7235 	    revert_file, &rfa, NULL, NULL, 1, 0);
7236 	if (err)
7237 		goto sync;
7238 
7239 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
7240 	    repo, progress_cb, progress_arg, NULL, NULL);
7241 sync:
7242 	sync_err = sync_fileindex(fileindex, fileindex_path);
7243 	if (sync_err && err == NULL)
7244 		err = sync_err;
7245 done:
7246 	got_ref_close(resolved);
7247 	free(tree_id);
7248 	free(commit_id);
7249 	if (commit)
7250 		got_object_commit_close(commit);
7251 	if (fileindex)
7252 		got_fileindex_free(fileindex);
7253 	free(fileindex_path);
7254 
7255 	unlockerr = lock_worktree(worktree, LOCK_SH);
7256 	if (unlockerr && err == NULL)
7257 		err = unlockerr;
7258 	return err;
7259 }
7260 
7261 const struct got_error *
7262 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
7263     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
7264     struct got_fileindex **fileindex, struct got_worktree *worktree,
7265     struct got_repository *repo)
7266 {
7267 	const struct got_error *err = NULL;
7268 	char *tmp_branch_name = NULL;
7269 	char *branch_ref_name = NULL;
7270 	char *base_commit_ref_name = NULL;
7271 	char *fileindex_path = NULL;
7272 	struct check_rebase_ok_arg ok_arg;
7273 	struct got_reference *wt_branch = NULL;
7274 	struct got_reference *base_commit_ref = NULL;
7275 
7276 	*tmp_branch = NULL;
7277 	*branch_ref = NULL;
7278 	*base_commit_id = NULL;
7279 	*fileindex = NULL;
7280 
7281 	err = lock_worktree(worktree, LOCK_EX);
7282 	if (err)
7283 		return err;
7284 
7285 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7286 	if (err)
7287 		goto done;
7288 
7289 	ok_arg.worktree = worktree;
7290 	ok_arg.repo = repo;
7291 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
7292 	    &ok_arg);
7293 	if (err)
7294 		goto done;
7295 
7296 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7297 	if (err)
7298 		goto done;
7299 
7300 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7301 	if (err)
7302 		goto done;
7303 
7304 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7305 	    worktree);
7306 	if (err)
7307 		goto done;
7308 
7309 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
7310 	    0);
7311 	if (err)
7312 		goto done;
7313 
7314 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
7315 	if (err)
7316 		goto done;
7317 
7318 	err = got_ref_write(*branch_ref, repo);
7319 	if (err)
7320 		goto done;
7321 
7322 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
7323 	    worktree->base_commit_id);
7324 	if (err)
7325 		goto done;
7326 	err = got_ref_write(base_commit_ref, repo);
7327 	if (err)
7328 		goto done;
7329 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
7330 	if (*base_commit_id == NULL) {
7331 		err = got_error_from_errno("got_object_id_dup");
7332 		goto done;
7333 	}
7334 
7335 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
7336 	    worktree->base_commit_id);
7337 	if (err)
7338 		goto done;
7339 	err = got_ref_write(*tmp_branch, repo);
7340 	if (err)
7341 		goto done;
7342 
7343 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
7344 	if (err)
7345 		goto done;
7346 done:
7347 	free(fileindex_path);
7348 	free(tmp_branch_name);
7349 	free(branch_ref_name);
7350 	free(base_commit_ref_name);
7351 	if (wt_branch)
7352 		got_ref_close(wt_branch);
7353 	if (err) {
7354 		if (*branch_ref) {
7355 			got_ref_close(*branch_ref);
7356 			*branch_ref = NULL;
7357 		}
7358 		if (*tmp_branch) {
7359 			got_ref_close(*tmp_branch);
7360 			*tmp_branch = NULL;
7361 		}
7362 		free(*base_commit_id);
7363 		if (*fileindex) {
7364 			got_fileindex_free(*fileindex);
7365 			*fileindex = NULL;
7366 		}
7367 		lock_worktree(worktree, LOCK_SH);
7368 	}
7369 	return err;
7370 }
7371 
7372 const struct got_error *
7373 got_worktree_histedit_postpone(struct got_worktree *worktree,
7374     struct got_fileindex *fileindex)
7375 {
7376 	if (fileindex)
7377 		got_fileindex_free(fileindex);
7378 	return lock_worktree(worktree, LOCK_SH);
7379 }
7380 
7381 const struct got_error *
7382 got_worktree_histedit_in_progress(int *in_progress,
7383     struct got_worktree *worktree)
7384 {
7385 	const struct got_error *err;
7386 	char *tmp_branch_name = NULL;
7387 
7388 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7389 	if (err)
7390 		return err;
7391 
7392 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
7393 	free(tmp_branch_name);
7394 	return NULL;
7395 }
7396 
7397 const struct got_error *
7398 got_worktree_histedit_continue(struct got_object_id **commit_id,
7399     struct got_reference **tmp_branch, struct got_reference **branch_ref,
7400     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
7401     struct got_worktree *worktree, struct got_repository *repo)
7402 {
7403 	const struct got_error *err;
7404 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
7405 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
7406 	struct got_reference *commit_ref = NULL;
7407 	struct got_reference *base_commit_ref = NULL;
7408 	char *fileindex_path = NULL;
7409 	int have_staged_files = 0;
7410 
7411 	*commit_id = NULL;
7412 	*tmp_branch = NULL;
7413 	*base_commit_id = NULL;
7414 	*fileindex = NULL;
7415 
7416 	err = lock_worktree(worktree, LOCK_EX);
7417 	if (err)
7418 		return err;
7419 
7420 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7421 	if (err)
7422 		goto done;
7423 
7424 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
7425 	    &have_staged_files);
7426 	if (err && err->code != GOT_ERR_CANCELLED)
7427 		goto done;
7428 	if (have_staged_files) {
7429 		err = got_error(GOT_ERR_STAGED_PATHS);
7430 		goto done;
7431 	}
7432 
7433 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7434 	if (err)
7435 		goto done;
7436 
7437 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7438 	if (err)
7439 		goto done;
7440 
7441 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7442 	if (err)
7443 		goto done;
7444 
7445 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7446 	    worktree);
7447 	if (err)
7448 		goto done;
7449 
7450 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
7451 	if (err)
7452 		goto done;
7453 
7454 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
7455 	if (err)
7456 		goto done;
7457 	err = got_ref_resolve(commit_id, repo, commit_ref);
7458 	if (err)
7459 		goto done;
7460 
7461 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
7462 	if (err)
7463 		goto done;
7464 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
7465 	if (err)
7466 		goto done;
7467 
7468 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
7469 	if (err)
7470 		goto done;
7471 done:
7472 	free(commit_ref_name);
7473 	free(branch_ref_name);
7474 	free(fileindex_path);
7475 	if (commit_ref)
7476 		got_ref_close(commit_ref);
7477 	if (base_commit_ref)
7478 		got_ref_close(base_commit_ref);
7479 	if (err) {
7480 		free(*commit_id);
7481 		*commit_id = NULL;
7482 		free(*base_commit_id);
7483 		*base_commit_id = NULL;
7484 		if (*tmp_branch) {
7485 			got_ref_close(*tmp_branch);
7486 			*tmp_branch = NULL;
7487 		}
7488 		if (*fileindex) {
7489 			got_fileindex_free(*fileindex);
7490 			*fileindex = NULL;
7491 		}
7492 		lock_worktree(worktree, LOCK_EX);
7493 	}
7494 	return err;
7495 }
7496 
7497 static const struct got_error *
7498 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
7499 {
7500 	const struct got_error *err;
7501 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
7502 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
7503 
7504 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7505 	if (err)
7506 		goto done;
7507 	err = delete_ref(tmp_branch_name, repo);
7508 	if (err)
7509 		goto done;
7510 
7511 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7512 	    worktree);
7513 	if (err)
7514 		goto done;
7515 	err = delete_ref(base_commit_ref_name, repo);
7516 	if (err)
7517 		goto done;
7518 
7519 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7520 	if (err)
7521 		goto done;
7522 	err = delete_ref(branch_ref_name, repo);
7523 	if (err)
7524 		goto done;
7525 
7526 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7527 	if (err)
7528 		goto done;
7529 	err = delete_ref(commit_ref_name, repo);
7530 	if (err)
7531 		goto done;
7532 done:
7533 	free(tmp_branch_name);
7534 	free(base_commit_ref_name);
7535 	free(branch_ref_name);
7536 	free(commit_ref_name);
7537 	return err;
7538 }
7539 
7540 const struct got_error *
7541 got_worktree_histedit_abort(struct got_worktree *worktree,
7542     struct got_fileindex *fileindex, struct got_repository *repo,
7543     struct got_reference *branch, struct got_object_id *base_commit_id,
7544     got_worktree_checkout_cb progress_cb, void *progress_arg)
7545 {
7546 	const struct got_error *err, *unlockerr, *sync_err;
7547 	struct got_reference *resolved = NULL;
7548 	char *fileindex_path = NULL;
7549 	struct got_commit_object *commit = NULL;
7550 	struct got_object_id *tree_id = NULL;
7551 	struct revert_file_args rfa;
7552 
7553 	err = lock_worktree(worktree, LOCK_EX);
7554 	if (err)
7555 		return err;
7556 
7557 	err = got_object_open_as_commit(&commit, repo,
7558 	    worktree->base_commit_id);
7559 	if (err)
7560 		goto done;
7561 
7562 	err = got_ref_open(&resolved, repo,
7563 	    got_ref_get_symref_target(branch), 0);
7564 	if (err)
7565 		goto done;
7566 
7567 	err = got_worktree_set_head_ref(worktree, resolved);
7568 	if (err)
7569 		goto done;
7570 
7571 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
7572 	if (err)
7573 		goto done;
7574 
7575 	err = got_object_id_by_path(&tree_id, repo, commit,
7576 	    worktree->path_prefix);
7577 	if (err)
7578 		goto done;
7579 
7580 	err = delete_histedit_refs(worktree, repo);
7581 	if (err)
7582 		goto done;
7583 
7584 	err = get_fileindex_path(&fileindex_path, worktree);
7585 	if (err)
7586 		goto done;
7587 
7588 	rfa.worktree = worktree;
7589 	rfa.fileindex = fileindex;
7590 	rfa.progress_cb = progress_cb;
7591 	rfa.progress_arg = progress_arg;
7592 	rfa.patch_cb = NULL;
7593 	rfa.patch_arg = NULL;
7594 	rfa.repo = repo;
7595 	rfa.unlink_added_files = 0;
7596 	err = worktree_status(worktree, "", fileindex, repo,
7597 	    revert_file, &rfa, NULL, NULL, 1, 0);
7598 	if (err)
7599 		goto sync;
7600 
7601 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
7602 	    repo, progress_cb, progress_arg, NULL, NULL);
7603 sync:
7604 	sync_err = sync_fileindex(fileindex, fileindex_path);
7605 	if (sync_err && err == NULL)
7606 		err = sync_err;
7607 done:
7608 	got_ref_close(resolved);
7609 	free(tree_id);
7610 	free(fileindex_path);
7611 
7612 	unlockerr = lock_worktree(worktree, LOCK_SH);
7613 	if (unlockerr && err == NULL)
7614 		err = unlockerr;
7615 	return err;
7616 }
7617 
7618 const struct got_error *
7619 got_worktree_histedit_complete(struct got_worktree *worktree,
7620     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
7621     struct got_reference *edited_branch, struct got_repository *repo)
7622 {
7623 	const struct got_error *err, *unlockerr, *sync_err;
7624 	struct got_object_id *new_head_commit_id = NULL;
7625 	struct got_reference *resolved = NULL;
7626 	char *fileindex_path = NULL;
7627 
7628 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
7629 	if (err)
7630 		return err;
7631 
7632 	err = got_ref_open(&resolved, repo,
7633 	    got_ref_get_symref_target(edited_branch), 0);
7634 	if (err)
7635 		goto done;
7636 
7637 	err = create_backup_ref(GOT_WORKTREE_HISTEDIT_BACKUP_REF_PREFIX,
7638 	    resolved, new_head_commit_id, repo);
7639 	if (err)
7640 		goto done;
7641 
7642 	err = got_ref_change_ref(resolved, new_head_commit_id);
7643 	if (err)
7644 		goto done;
7645 
7646 	err = got_ref_write(resolved, repo);
7647 	if (err)
7648 		goto done;
7649 
7650 	err = got_worktree_set_head_ref(worktree, resolved);
7651 	if (err)
7652 		goto done;
7653 
7654 	err = delete_histedit_refs(worktree, repo);
7655 	if (err)
7656 		goto done;
7657 
7658 	err = get_fileindex_path(&fileindex_path, worktree);
7659 	if (err)
7660 		goto done;
7661 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7662 	sync_err = sync_fileindex(fileindex, fileindex_path);
7663 	if (sync_err && err == NULL)
7664 		err = sync_err;
7665 done:
7666 	got_fileindex_free(fileindex);
7667 	free(fileindex_path);
7668 	free(new_head_commit_id);
7669 	unlockerr = lock_worktree(worktree, LOCK_SH);
7670 	if (unlockerr && err == NULL)
7671 		err = unlockerr;
7672 	return err;
7673 }
7674 
7675 const struct got_error *
7676 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
7677     struct got_object_id *commit_id, struct got_repository *repo)
7678 {
7679 	const struct got_error *err;
7680 	char *commit_ref_name;
7681 
7682 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7683 	if (err)
7684 		return err;
7685 
7686 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
7687 	if (err)
7688 		goto done;
7689 
7690 	err = delete_ref(commit_ref_name, repo);
7691 done:
7692 	free(commit_ref_name);
7693 	return err;
7694 }
7695 
7696 const struct got_error *
7697 got_worktree_integrate_prepare(struct got_fileindex **fileindex,
7698     struct got_reference **branch_ref, struct got_reference **base_branch_ref,
7699     struct got_worktree *worktree, const char *refname,
7700     struct got_repository *repo)
7701 {
7702 	const struct got_error *err = NULL;
7703 	char *fileindex_path = NULL;
7704 	struct check_rebase_ok_arg ok_arg;
7705 
7706 	*fileindex = NULL;
7707 	*branch_ref = NULL;
7708 	*base_branch_ref = NULL;
7709 
7710 	err = lock_worktree(worktree, LOCK_EX);
7711 	if (err)
7712 		return err;
7713 
7714 	if (strcmp(refname, got_worktree_get_head_ref_name(worktree)) == 0) {
7715 		err = got_error_msg(GOT_ERR_SAME_BRANCH,
7716 		    "cannot integrate a branch into itself; "
7717 		    "update -b or different branch name required");
7718 		goto done;
7719 	}
7720 
7721 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7722 	if (err)
7723 		goto done;
7724 
7725 	/* Preconditions are the same as for rebase. */
7726 	ok_arg.worktree = worktree;
7727 	ok_arg.repo = repo;
7728 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
7729 	    &ok_arg);
7730 	if (err)
7731 		goto done;
7732 
7733 	err = got_ref_open(branch_ref, repo, refname, 1);
7734 	if (err)
7735 		goto done;
7736 
7737 	err = got_ref_open(base_branch_ref, repo,
7738 	    got_worktree_get_head_ref_name(worktree), 1);
7739 done:
7740 	if (err) {
7741 		if (*branch_ref) {
7742 			got_ref_close(*branch_ref);
7743 			*branch_ref = NULL;
7744 		}
7745 		if (*base_branch_ref) {
7746 			got_ref_close(*base_branch_ref);
7747 			*base_branch_ref = NULL;
7748 		}
7749 		if (*fileindex) {
7750 			got_fileindex_free(*fileindex);
7751 			*fileindex = NULL;
7752 		}
7753 		lock_worktree(worktree, LOCK_SH);
7754 	}
7755 	return err;
7756 }
7757 
7758 const struct got_error *
7759 got_worktree_integrate_continue(struct got_worktree *worktree,
7760     struct got_fileindex *fileindex, struct got_repository *repo,
7761     struct got_reference *branch_ref, struct got_reference *base_branch_ref,
7762     got_worktree_checkout_cb progress_cb, void *progress_arg,
7763     got_cancel_cb cancel_cb, void *cancel_arg)
7764 {
7765 	const struct got_error *err = NULL, *sync_err, *unlockerr;
7766 	char *fileindex_path = NULL;
7767 	struct got_object_id *tree_id = NULL, *commit_id = NULL;
7768 	struct got_commit_object *commit =  NULL;
7769 
7770 	err = get_fileindex_path(&fileindex_path, worktree);
7771 	if (err)
7772 		goto done;
7773 
7774 	err = got_ref_resolve(&commit_id, repo, branch_ref);
7775 	if (err)
7776 		goto done;
7777 
7778 	err = got_object_open_as_commit(&commit, repo, commit_id);
7779 	if (err)
7780 		goto done;
7781 
7782 	err = got_object_id_by_path(&tree_id, repo, commit,
7783 	    worktree->path_prefix);
7784 	if (err)
7785 		goto done;
7786 
7787 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
7788 	if (err)
7789 		goto done;
7790 
7791 	err = checkout_files(worktree, fileindex, "", tree_id, NULL, repo,
7792 	    progress_cb, progress_arg, cancel_cb, cancel_arg);
7793 	if (err)
7794 		goto sync;
7795 
7796 	err = got_ref_change_ref(base_branch_ref, commit_id);
7797 	if (err)
7798 		goto sync;
7799 
7800 	err = got_ref_write(base_branch_ref, repo);
7801 	if (err)
7802 		goto sync;
7803 
7804 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7805 sync:
7806 	sync_err = sync_fileindex(fileindex, fileindex_path);
7807 	if (sync_err && err == NULL)
7808 		err = sync_err;
7809 
7810 done:
7811 	unlockerr = got_ref_unlock(branch_ref);
7812 	if (unlockerr && err == NULL)
7813 		err = unlockerr;
7814 	got_ref_close(branch_ref);
7815 
7816 	unlockerr = got_ref_unlock(base_branch_ref);
7817 	if (unlockerr && err == NULL)
7818 		err = unlockerr;
7819 	got_ref_close(base_branch_ref);
7820 
7821 	got_fileindex_free(fileindex);
7822 	free(fileindex_path);
7823 	free(tree_id);
7824 	if (commit)
7825 		got_object_commit_close(commit);
7826 
7827 	unlockerr = lock_worktree(worktree, LOCK_SH);
7828 	if (unlockerr && err == NULL)
7829 		err = unlockerr;
7830 	return err;
7831 }
7832 
7833 const struct got_error *
7834 got_worktree_integrate_abort(struct got_worktree *worktree,
7835     struct got_fileindex *fileindex, struct got_repository *repo,
7836     struct got_reference *branch_ref, struct got_reference *base_branch_ref)
7837 {
7838 	const struct got_error *err = NULL, *unlockerr = NULL;
7839 
7840 	got_fileindex_free(fileindex);
7841 
7842 	err = lock_worktree(worktree, LOCK_SH);
7843 
7844 	unlockerr = got_ref_unlock(branch_ref);
7845 	if (unlockerr && err == NULL)
7846 		err = unlockerr;
7847 	got_ref_close(branch_ref);
7848 
7849 	unlockerr = got_ref_unlock(base_branch_ref);
7850 	if (unlockerr && err == NULL)
7851 		err = unlockerr;
7852 	got_ref_close(base_branch_ref);
7853 
7854 	return err;
7855 }
7856 
7857 const struct got_error *
7858 got_worktree_merge_postpone(struct got_worktree *worktree,
7859     struct got_fileindex *fileindex)
7860 {
7861 	const struct got_error *err, *sync_err;
7862 	char *fileindex_path = NULL;
7863 
7864 	err = get_fileindex_path(&fileindex_path, worktree);
7865 	if (err)
7866 		goto done;
7867 
7868 	sync_err = sync_fileindex(fileindex, fileindex_path);
7869 
7870 	err = lock_worktree(worktree, LOCK_SH);
7871 	if (sync_err && err == NULL)
7872 		err = sync_err;
7873 done:
7874 	got_fileindex_free(fileindex);
7875 	free(fileindex_path);
7876 	return err;
7877 }
7878 
7879 static const struct got_error *
7880 delete_merge_refs(struct got_worktree *worktree, struct got_repository *repo)
7881 {
7882 	const struct got_error *err;
7883 	char *branch_refname = NULL, *commit_refname = NULL;
7884 
7885 	err = get_merge_branch_ref_name(&branch_refname, worktree);
7886 	if (err)
7887 		goto done;
7888 	err = delete_ref(branch_refname, repo);
7889 	if (err)
7890 		goto done;
7891 
7892 	err = get_merge_commit_ref_name(&commit_refname, worktree);
7893 	if (err)
7894 		goto done;
7895 	err = delete_ref(commit_refname, repo);
7896 	if (err)
7897 		goto done;
7898 
7899 done:
7900 	free(branch_refname);
7901 	free(commit_refname);
7902 	return err;
7903 }
7904 
7905 struct merge_commit_msg_arg {
7906 	struct got_worktree *worktree;
7907 	const char *branch_name;
7908 };
7909 
7910 static const struct got_error *
7911 merge_commit_msg_cb(struct got_pathlist_head *commitable_paths,
7912     const char *diff_path, char **logmsg, void *arg)
7913 {
7914 	struct merge_commit_msg_arg *a = arg;
7915 
7916 	if (asprintf(logmsg, "merge %s into %s\n", a->branch_name,
7917 	    got_worktree_get_head_ref_name(a->worktree)) == -1)
7918 		return got_error_from_errno("asprintf");
7919 
7920 	return NULL;
7921 }
7922 
7923 
7924 const struct got_error *
7925 got_worktree_merge_branch(struct got_worktree *worktree,
7926     struct got_fileindex *fileindex,
7927     struct got_object_id *yca_commit_id,
7928     struct got_object_id *branch_tip,
7929     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
7930     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
7931 {
7932 	const struct got_error *err;
7933 	char *fileindex_path = NULL;
7934 
7935 	err = get_fileindex_path(&fileindex_path, worktree);
7936 	if (err)
7937 		goto done;
7938 
7939 	err = got_fileindex_for_each_entry_safe(fileindex, check_mixed_commits,
7940 	    worktree);
7941 	if (err)
7942 		goto done;
7943 
7944 	err = merge_files(worktree, fileindex, fileindex_path, yca_commit_id,
7945 	    branch_tip, repo, progress_cb, progress_arg,
7946 	    cancel_cb, cancel_arg);
7947 done:
7948 	free(fileindex_path);
7949 	return err;
7950 }
7951 
7952 const struct got_error *
7953 got_worktree_merge_commit(struct got_object_id **new_commit_id,
7954     struct got_worktree *worktree, struct got_fileindex *fileindex,
7955     const char *author, const char *committer, int allow_bad_symlinks,
7956     struct got_object_id *branch_tip, const char *branch_name,
7957     int allow_conflict, struct got_repository *repo,
7958     got_worktree_status_cb status_cb, void *status_arg)
7959 
7960 {
7961 	const struct got_error *err = NULL, *sync_err;
7962 	struct got_pathlist_head commitable_paths;
7963 	struct collect_commitables_arg cc_arg;
7964 	struct got_pathlist_entry *pe;
7965 	struct got_reference *head_ref = NULL;
7966 	struct got_object_id *head_commit_id = NULL;
7967 	int have_staged_files = 0;
7968 	struct merge_commit_msg_arg mcm_arg;
7969 	char *fileindex_path = NULL;
7970 
7971 	memset(&cc_arg, 0, sizeof(cc_arg));
7972 	*new_commit_id = NULL;
7973 
7974 	TAILQ_INIT(&commitable_paths);
7975 
7976 	err = get_fileindex_path(&fileindex_path, worktree);
7977 	if (err)
7978 		goto done;
7979 
7980 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
7981 	if (err)
7982 		goto done;
7983 
7984 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
7985 	if (err)
7986 		goto done;
7987 
7988 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
7989 	    &have_staged_files);
7990 	if (err && err->code != GOT_ERR_CANCELLED)
7991 		goto done;
7992 	if (have_staged_files) {
7993 		err = got_error(GOT_ERR_MERGE_STAGED_PATHS);
7994 		goto done;
7995 	}
7996 
7997 	cc_arg.commitable_paths = &commitable_paths;
7998 	cc_arg.worktree = worktree;
7999 	cc_arg.fileindex = fileindex;
8000 	cc_arg.repo = repo;
8001 	cc_arg.have_staged_files = have_staged_files;
8002 	cc_arg.allow_bad_symlinks = allow_bad_symlinks;
8003 	cc_arg.commit_conflicts = allow_conflict;
8004 	err = worktree_status(worktree, "", fileindex, repo,
8005 	    collect_commitables, &cc_arg, NULL, NULL, 1, 0);
8006 	if (err)
8007 		goto done;
8008 
8009 	if (TAILQ_EMPTY(&commitable_paths)) {
8010 		err = got_error_fmt(GOT_ERR_COMMIT_NO_CHANGES,
8011 		    "merge of %s cannot proceed", branch_name);
8012 		goto done;
8013 	}
8014 
8015 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
8016 		struct got_commitable *ct = pe->data;
8017 		const char *ct_path = ct->in_repo_path;
8018 
8019 		while (ct_path[0] == '/')
8020 			ct_path++;
8021 		err = check_out_of_date(ct_path, ct->status,
8022 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
8023 		    head_commit_id, repo, GOT_ERR_MERGE_COMMIT_OUT_OF_DATE);
8024 		if (err)
8025 			goto done;
8026 
8027 	}
8028 
8029 	mcm_arg.worktree = worktree;
8030 	mcm_arg.branch_name = branch_name;
8031 	err = commit_worktree(new_commit_id, &commitable_paths,
8032 	    head_commit_id, branch_tip, worktree, author, committer, NULL,
8033 	    merge_commit_msg_cb, &mcm_arg, status_cb, status_arg, repo);
8034 	if (err)
8035 		goto done;
8036 
8037 	err = update_fileindex_after_commit(worktree, &commitable_paths,
8038 	    *new_commit_id, fileindex, have_staged_files);
8039 	sync_err = sync_fileindex(fileindex, fileindex_path);
8040 	if (sync_err && err == NULL)
8041 		err = sync_err;
8042 done:
8043 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
8044 		struct got_commitable *ct = pe->data;
8045 
8046 		free_commitable(ct);
8047 	}
8048 	got_pathlist_free(&commitable_paths, GOT_PATHLIST_FREE_NONE);
8049 	free(fileindex_path);
8050 	return err;
8051 }
8052 
8053 const struct got_error *
8054 got_worktree_merge_complete(struct got_worktree *worktree,
8055     struct got_fileindex *fileindex, struct got_repository *repo)
8056 {
8057 	const struct got_error *err, *unlockerr, *sync_err;
8058 	char *fileindex_path = NULL;
8059 
8060 	err = delete_merge_refs(worktree, repo);
8061 	if (err)
8062 		goto done;
8063 
8064 	err = get_fileindex_path(&fileindex_path, worktree);
8065 	if (err)
8066 		goto done;
8067 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
8068 	sync_err = sync_fileindex(fileindex, fileindex_path);
8069 	if (sync_err && err == NULL)
8070 		err = sync_err;
8071 done:
8072 	got_fileindex_free(fileindex);
8073 	free(fileindex_path);
8074 	unlockerr = lock_worktree(worktree, LOCK_SH);
8075 	if (unlockerr && err == NULL)
8076 		err = unlockerr;
8077 	return err;
8078 }
8079 
8080 const struct got_error *
8081 got_worktree_merge_in_progress(int *in_progress, struct got_worktree *worktree,
8082     struct got_repository *repo)
8083 {
8084 	const struct got_error *err;
8085 	char *branch_refname = NULL;
8086 	struct got_reference *branch_ref = NULL;
8087 
8088 	*in_progress = 0;
8089 
8090 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8091 	if (err)
8092 		return err;
8093 	err = got_ref_open(&branch_ref, repo, branch_refname, 0);
8094 	free(branch_refname);
8095 	if (err) {
8096 		if (err->code != GOT_ERR_NOT_REF)
8097 			return err;
8098 	} else
8099 		*in_progress = 1;
8100 
8101 	return NULL;
8102 }
8103 
8104 const struct got_error *got_worktree_merge_prepare(
8105     struct got_fileindex **fileindex, struct got_worktree *worktree,
8106     struct got_reference *branch, struct got_repository *repo)
8107 {
8108 	const struct got_error *err = NULL;
8109 	char *fileindex_path = NULL;
8110 	char *branch_refname = NULL, *commit_refname = NULL;
8111 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
8112 	struct got_reference *commit_ref = NULL;
8113 	struct got_object_id *branch_tip = NULL, *wt_branch_tip = NULL;
8114 	struct check_rebase_ok_arg ok_arg;
8115 
8116 	*fileindex = NULL;
8117 
8118 	err = lock_worktree(worktree, LOCK_EX);
8119 	if (err)
8120 		return err;
8121 
8122 	err = open_fileindex(fileindex, &fileindex_path, worktree);
8123 	if (err)
8124 		goto done;
8125 
8126 	/* Preconditions are the same as for rebase. */
8127 	ok_arg.worktree = worktree;
8128 	ok_arg.repo = repo;
8129 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
8130 	    &ok_arg);
8131 	if (err)
8132 		goto done;
8133 
8134 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8135 	if (err)
8136 		return err;
8137 
8138 	err = get_merge_commit_ref_name(&commit_refname, worktree);
8139 	if (err)
8140 		return err;
8141 
8142 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
8143 	    0);
8144 	if (err)
8145 		goto done;
8146 
8147 	err = got_ref_resolve(&wt_branch_tip, repo, wt_branch);
8148 	if (err)
8149 		goto done;
8150 
8151 	if (got_object_id_cmp(worktree->base_commit_id, wt_branch_tip) != 0) {
8152 		err = got_error(GOT_ERR_MERGE_OUT_OF_DATE);
8153 		goto done;
8154 	}
8155 
8156 	err = got_ref_resolve(&branch_tip, repo, branch);
8157 	if (err)
8158 		goto done;
8159 
8160 	err = got_ref_alloc_symref(&branch_ref, branch_refname, branch);
8161 	if (err)
8162 		goto done;
8163 	err = got_ref_write(branch_ref, repo);
8164 	if (err)
8165 		goto done;
8166 
8167 	err = got_ref_alloc(&commit_ref, commit_refname, branch_tip);
8168 	if (err)
8169 		goto done;
8170 	err = got_ref_write(commit_ref, repo);
8171 	if (err)
8172 		goto done;
8173 
8174 done:
8175 	free(branch_refname);
8176 	free(commit_refname);
8177 	free(fileindex_path);
8178 	if (branch_ref)
8179 		got_ref_close(branch_ref);
8180 	if (commit_ref)
8181 		got_ref_close(commit_ref);
8182 	if (wt_branch)
8183 		got_ref_close(wt_branch);
8184 	free(wt_branch_tip);
8185 	if (err) {
8186 		if (*fileindex) {
8187 			got_fileindex_free(*fileindex);
8188 			*fileindex = NULL;
8189 		}
8190 		lock_worktree(worktree, LOCK_SH);
8191 	}
8192 	return err;
8193 }
8194 
8195 const struct got_error *
8196 got_worktree_merge_continue(char **branch_name,
8197     struct got_object_id **branch_tip, struct got_fileindex **fileindex,
8198     struct got_worktree *worktree, struct got_repository *repo)
8199 {
8200 	const struct got_error *err;
8201 	char *commit_refname = NULL, *branch_refname = NULL;
8202 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
8203 	char *fileindex_path = NULL;
8204 	int have_staged_files = 0;
8205 
8206 	*branch_name = NULL;
8207 	*branch_tip = NULL;
8208 	*fileindex = NULL;
8209 
8210 	err = lock_worktree(worktree, LOCK_EX);
8211 	if (err)
8212 		return err;
8213 
8214 	err = open_fileindex(fileindex, &fileindex_path, worktree);
8215 	if (err)
8216 		goto done;
8217 
8218 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
8219 	    &have_staged_files);
8220 	if (err && err->code != GOT_ERR_CANCELLED)
8221 		goto done;
8222 	if (have_staged_files) {
8223 		err = got_error(GOT_ERR_STAGED_PATHS);
8224 		goto done;
8225 	}
8226 
8227 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8228 	if (err)
8229 		goto done;
8230 
8231 	err = get_merge_commit_ref_name(&commit_refname, worktree);
8232 	if (err)
8233 		goto done;
8234 
8235 	err = got_ref_open(&branch_ref, repo, branch_refname, 0);
8236 	if (err)
8237 		goto done;
8238 
8239 	if (!got_ref_is_symbolic(branch_ref)) {
8240 		err = got_error_fmt(GOT_ERR_BAD_REF_TYPE,
8241 		    "%s is not a symbolic reference",
8242 		    got_ref_get_name(branch_ref));
8243 		goto done;
8244 	}
8245 	*branch_name = strdup(got_ref_get_symref_target(branch_ref));
8246 	if (*branch_name == NULL) {
8247 		err = got_error_from_errno("strdup");
8248 		goto done;
8249 	}
8250 
8251 	err = got_ref_open(&commit_ref, repo, commit_refname, 0);
8252 	if (err)
8253 		goto done;
8254 
8255 	err = got_ref_resolve(branch_tip, repo, commit_ref);
8256 	if (err)
8257 		goto done;
8258 done:
8259 	free(commit_refname);
8260 	free(branch_refname);
8261 	free(fileindex_path);
8262 	if (commit_ref)
8263 		got_ref_close(commit_ref);
8264 	if (branch_ref)
8265 		got_ref_close(branch_ref);
8266 	if (err) {
8267 		if (*branch_name) {
8268 			free(*branch_name);
8269 			*branch_name = NULL;
8270 		}
8271 		free(*branch_tip);
8272 		*branch_tip = NULL;
8273 		if (*fileindex) {
8274 			got_fileindex_free(*fileindex);
8275 			*fileindex = NULL;
8276 		}
8277 		lock_worktree(worktree, LOCK_SH);
8278 	}
8279 	return err;
8280 }
8281 
8282 const struct got_error *
8283 got_worktree_merge_abort(struct got_worktree *worktree,
8284     struct got_fileindex *fileindex, struct got_repository *repo,
8285     got_worktree_checkout_cb progress_cb, void *progress_arg)
8286 {
8287 	const struct got_error *err, *unlockerr, *sync_err;
8288 	struct got_object_id *commit_id = NULL;
8289 	struct got_commit_object *commit = NULL;
8290 	char *fileindex_path = NULL;
8291 	struct revert_file_args rfa;
8292 	struct got_object_id *tree_id = NULL;
8293 
8294 	err = got_object_open_as_commit(&commit, repo,
8295 	    worktree->base_commit_id);
8296 	if (err)
8297 		goto done;
8298 
8299 	err = got_object_id_by_path(&tree_id, repo, commit,
8300 	    worktree->path_prefix);
8301 	if (err)
8302 		goto done;
8303 
8304 	err = delete_merge_refs(worktree, repo);
8305 	if (err)
8306 		goto done;
8307 
8308 	err = get_fileindex_path(&fileindex_path, worktree);
8309 	if (err)
8310 		goto done;
8311 
8312 	rfa.worktree = worktree;
8313 	rfa.fileindex = fileindex;
8314 	rfa.progress_cb = progress_cb;
8315 	rfa.progress_arg = progress_arg;
8316 	rfa.patch_cb = NULL;
8317 	rfa.patch_arg = NULL;
8318 	rfa.repo = repo;
8319 	rfa.unlink_added_files = 1;
8320 	err = worktree_status(worktree, "", fileindex, repo,
8321 	    revert_file, &rfa, NULL, NULL, 1, 0);
8322 	if (err)
8323 		goto sync;
8324 
8325 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
8326 	    repo, progress_cb, progress_arg, NULL, NULL);
8327 sync:
8328 	sync_err = sync_fileindex(fileindex, fileindex_path);
8329 	if (sync_err && err == NULL)
8330 		err = sync_err;
8331 done:
8332 	free(tree_id);
8333 	free(commit_id);
8334 	if (commit)
8335 		got_object_commit_close(commit);
8336 	if (fileindex)
8337 		got_fileindex_free(fileindex);
8338 	free(fileindex_path);
8339 
8340 	unlockerr = lock_worktree(worktree, LOCK_SH);
8341 	if (unlockerr && err == NULL)
8342 		err = unlockerr;
8343 	return err;
8344 }
8345 
8346 struct check_stage_ok_arg {
8347 	struct got_object_id *head_commit_id;
8348 	struct got_worktree *worktree;
8349 	struct got_fileindex *fileindex;
8350 	struct got_repository *repo;
8351 	int have_changes;
8352 };
8353 
8354 static const struct got_error *
8355 check_stage_ok(void *arg, unsigned char status,
8356     unsigned char staged_status, const char *relpath,
8357     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8358     struct got_object_id *commit_id, int dirfd, const char *de_name)
8359 {
8360 	struct check_stage_ok_arg *a = arg;
8361 	const struct got_error *err = NULL;
8362 	struct got_fileindex_entry *ie;
8363 	struct got_object_id base_commit_id;
8364 	struct got_object_id *base_commit_idp = NULL;
8365 	char *in_repo_path = NULL, *p;
8366 
8367 	if (status == GOT_STATUS_UNVERSIONED ||
8368 	    status == GOT_STATUS_NO_CHANGE)
8369 		return NULL;
8370 	if (status == GOT_STATUS_NONEXISTENT)
8371 		return got_error_set_errno(ENOENT, relpath);
8372 
8373 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8374 	if (ie == NULL)
8375 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8376 
8377 	if (asprintf(&in_repo_path, "%s%s%s", a->worktree->path_prefix,
8378 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
8379 	    relpath) == -1)
8380 		return got_error_from_errno("asprintf");
8381 
8382 	if (got_fileindex_entry_has_commit(ie)) {
8383 		base_commit_idp = got_fileindex_entry_get_commit_id(
8384 		    &base_commit_id, ie);
8385 	}
8386 
8387 	if (status == GOT_STATUS_CONFLICT) {
8388 		err = got_error_path(ie->path, GOT_ERR_STAGE_CONFLICT);
8389 		goto done;
8390 	} else if (status != GOT_STATUS_ADD &&
8391 	    status != GOT_STATUS_MODIFY &&
8392 	    status != GOT_STATUS_DELETE) {
8393 		err = got_error_path(ie->path, GOT_ERR_FILE_STATUS);
8394 		goto done;
8395 	}
8396 
8397 	a->have_changes = 1;
8398 
8399 	p = in_repo_path;
8400 	while (p[0] == '/')
8401 		p++;
8402 	err = check_out_of_date(p, status, staged_status,
8403 	    blob_id, base_commit_idp, a->head_commit_id, a->repo,
8404 	    GOT_ERR_STAGE_OUT_OF_DATE);
8405 done:
8406 	free(in_repo_path);
8407 	return err;
8408 }
8409 
8410 struct stage_path_arg {
8411 	struct got_worktree *worktree;
8412 	struct got_fileindex *fileindex;
8413 	struct got_repository *repo;
8414 	got_worktree_status_cb status_cb;
8415 	void *status_arg;
8416 	got_worktree_patch_cb patch_cb;
8417 	void *patch_arg;
8418 	int staged_something;
8419 	int allow_bad_symlinks;
8420 };
8421 
8422 static const struct got_error *
8423 stage_path(void *arg, unsigned char status,
8424     unsigned char staged_status, const char *relpath,
8425     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8426     struct got_object_id *commit_id, int dirfd, const char *de_name)
8427 {
8428 	struct stage_path_arg *a = arg;
8429 	const struct got_error *err = NULL;
8430 	struct got_fileindex_entry *ie;
8431 	char *ondisk_path = NULL, *path_content = NULL;
8432 	uint32_t stage;
8433 	struct got_object_id *new_staged_blob_id = NULL;
8434 	struct stat sb;
8435 
8436 	if (status == GOT_STATUS_UNVERSIONED)
8437 		return NULL;
8438 
8439 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8440 	if (ie == NULL)
8441 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8442 
8443 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
8444 	    relpath)== -1)
8445 		return got_error_from_errno("asprintf");
8446 
8447 	switch (status) {
8448 	case GOT_STATUS_ADD:
8449 	case GOT_STATUS_MODIFY:
8450 		/* XXX could sb.st_mode be passed in by our caller? */
8451 		if (lstat(ondisk_path, &sb) == -1) {
8452 			err = got_error_from_errno2("lstat", ondisk_path);
8453 			break;
8454 		}
8455 		if (a->patch_cb) {
8456 			if (status == GOT_STATUS_ADD) {
8457 				int choice = GOT_PATCH_CHOICE_NONE;
8458 				err = (*a->patch_cb)(&choice, a->patch_arg,
8459 				    status, ie->path, NULL, 1, 1);
8460 				if (err)
8461 					break;
8462 				if (choice != GOT_PATCH_CHOICE_YES)
8463 					break;
8464 			} else {
8465 				err = create_patched_content(&path_content, 0,
8466 				    staged_blob_id ? staged_blob_id : blob_id,
8467 				    ondisk_path, dirfd, de_name, ie->path,
8468 				    a->repo, a->patch_cb, a->patch_arg);
8469 				if (err || path_content == NULL)
8470 					break;
8471 			}
8472 		}
8473 		err = got_object_blob_create(&new_staged_blob_id,
8474 		    path_content ? path_content : ondisk_path, a->repo);
8475 		if (err)
8476 			break;
8477 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
8478 		    SHA1_DIGEST_LENGTH);
8479 		if (status == GOT_STATUS_ADD || staged_status == GOT_STATUS_ADD)
8480 			stage = GOT_FILEIDX_STAGE_ADD;
8481 		else
8482 			stage = GOT_FILEIDX_STAGE_MODIFY;
8483 		got_fileindex_entry_stage_set(ie, stage);
8484 		if (S_ISLNK(sb.st_mode)) {
8485 			int is_bad_symlink = 0;
8486 			if (!a->allow_bad_symlinks) {
8487 				char target_path[PATH_MAX];
8488 				ssize_t target_len;
8489 				target_len = readlink(ondisk_path, target_path,
8490 				    sizeof(target_path));
8491 				if (target_len == -1) {
8492 					err = got_error_from_errno2("readlink",
8493 					    ondisk_path);
8494 					break;
8495 				}
8496 				err = is_bad_symlink_target(&is_bad_symlink,
8497 				    target_path, target_len, ondisk_path,
8498 				    a->worktree->root_path);
8499 				if (err)
8500 					break;
8501 				if (is_bad_symlink) {
8502 					err = got_error_path(ondisk_path,
8503 					    GOT_ERR_BAD_SYMLINK);
8504 					break;
8505 				}
8506 			}
8507 			if (is_bad_symlink)
8508 				got_fileindex_entry_staged_filetype_set(ie,
8509 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
8510 			else
8511 				got_fileindex_entry_staged_filetype_set(ie,
8512 				    GOT_FILEIDX_MODE_SYMLINK);
8513 		} else {
8514 			got_fileindex_entry_staged_filetype_set(ie,
8515 			    GOT_FILEIDX_MODE_REGULAR_FILE);
8516 		}
8517 		a->staged_something = 1;
8518 		if (a->status_cb == NULL)
8519 			break;
8520 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
8521 		    get_staged_status(ie), relpath, blob_id,
8522 		    new_staged_blob_id, NULL, dirfd, de_name);
8523 		if (err)
8524 			break;
8525 		/*
8526 		 * When staging the reverse of the staged diff,
8527 		 * implicitly unstage the file.
8528 		 */
8529 		if (memcmp(ie->staged_blob_sha1, ie->blob_sha1,
8530 		    sizeof(ie->blob_sha1)) == 0) {
8531 			got_fileindex_entry_stage_set(ie,
8532 			    GOT_FILEIDX_STAGE_NONE);
8533 		}
8534 		break;
8535 	case GOT_STATUS_DELETE:
8536 		if (staged_status == GOT_STATUS_DELETE)
8537 			break;
8538 		if (a->patch_cb) {
8539 			int choice = GOT_PATCH_CHOICE_NONE;
8540 			err = (*a->patch_cb)(&choice, a->patch_arg, status,
8541 			    ie->path, NULL, 1, 1);
8542 			if (err)
8543 				break;
8544 			if (choice == GOT_PATCH_CHOICE_NO)
8545 				break;
8546 			if (choice != GOT_PATCH_CHOICE_YES) {
8547 				err = got_error(GOT_ERR_PATCH_CHOICE);
8548 				break;
8549 			}
8550 		}
8551 		stage = GOT_FILEIDX_STAGE_DELETE;
8552 		got_fileindex_entry_stage_set(ie, stage);
8553 		a->staged_something = 1;
8554 		if (a->status_cb == NULL)
8555 			break;
8556 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
8557 		    get_staged_status(ie), relpath, NULL, NULL, NULL, dirfd,
8558 		    de_name);
8559 		break;
8560 	case GOT_STATUS_NO_CHANGE:
8561 		break;
8562 	case GOT_STATUS_CONFLICT:
8563 		err = got_error_path(relpath, GOT_ERR_STAGE_CONFLICT);
8564 		break;
8565 	case GOT_STATUS_NONEXISTENT:
8566 		err = got_error_set_errno(ENOENT, relpath);
8567 		break;
8568 	default:
8569 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
8570 		break;
8571 	}
8572 
8573 	if (path_content && unlink(path_content) == -1 && err == NULL)
8574 		err = got_error_from_errno2("unlink", path_content);
8575 	free(path_content);
8576 	free(ondisk_path);
8577 	free(new_staged_blob_id);
8578 	return err;
8579 }
8580 
8581 const struct got_error *
8582 got_worktree_stage(struct got_worktree *worktree,
8583     struct got_pathlist_head *paths,
8584     got_worktree_status_cb status_cb, void *status_arg,
8585     got_worktree_patch_cb patch_cb, void *patch_arg,
8586     int allow_bad_symlinks, struct got_repository *repo)
8587 {
8588 	const struct got_error *err = NULL, *sync_err, *unlockerr;
8589 	struct got_pathlist_entry *pe;
8590 	struct got_fileindex *fileindex = NULL;
8591 	char *fileindex_path = NULL;
8592 	struct got_reference *head_ref = NULL;
8593 	struct got_object_id *head_commit_id = NULL;
8594 	struct check_stage_ok_arg oka;
8595 	struct stage_path_arg spa;
8596 
8597 	err = lock_worktree(worktree, LOCK_EX);
8598 	if (err)
8599 		return err;
8600 
8601 	err = got_ref_open(&head_ref, repo,
8602 	    got_worktree_get_head_ref_name(worktree), 0);
8603 	if (err)
8604 		goto done;
8605 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
8606 	if (err)
8607 		goto done;
8608 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
8609 	if (err)
8610 		goto done;
8611 
8612 	/* Check pre-conditions before staging anything. */
8613 	oka.head_commit_id = head_commit_id;
8614 	oka.worktree = worktree;
8615 	oka.fileindex = fileindex;
8616 	oka.repo = repo;
8617 	oka.have_changes = 0;
8618 	TAILQ_FOREACH(pe, paths, entry) {
8619 		err = worktree_status(worktree, pe->path, fileindex, repo,
8620 		    check_stage_ok, &oka, NULL, NULL, 1, 0);
8621 		if (err)
8622 			goto done;
8623 	}
8624 	if (!oka.have_changes) {
8625 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
8626 		goto done;
8627 	}
8628 
8629 	spa.worktree = worktree;
8630 	spa.fileindex = fileindex;
8631 	spa.repo = repo;
8632 	spa.patch_cb = patch_cb;
8633 	spa.patch_arg = patch_arg;
8634 	spa.status_cb = status_cb;
8635 	spa.status_arg = status_arg;
8636 	spa.staged_something = 0;
8637 	spa.allow_bad_symlinks = allow_bad_symlinks;
8638 	TAILQ_FOREACH(pe, paths, entry) {
8639 		err = worktree_status(worktree, pe->path, fileindex, repo,
8640 		    stage_path, &spa, NULL, NULL, 1, 0);
8641 		if (err)
8642 			goto done;
8643 	}
8644 	if (!spa.staged_something) {
8645 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
8646 		goto done;
8647 	}
8648 
8649 	sync_err = sync_fileindex(fileindex, fileindex_path);
8650 	if (sync_err && err == NULL)
8651 		err = sync_err;
8652 done:
8653 	if (head_ref)
8654 		got_ref_close(head_ref);
8655 	free(head_commit_id);
8656 	free(fileindex_path);
8657 	if (fileindex)
8658 		got_fileindex_free(fileindex);
8659 	unlockerr = lock_worktree(worktree, LOCK_SH);
8660 	if (unlockerr && err == NULL)
8661 		err = unlockerr;
8662 	return err;
8663 }
8664 
8665 struct unstage_path_arg {
8666 	struct got_worktree *worktree;
8667 	struct got_fileindex *fileindex;
8668 	struct got_repository *repo;
8669 	got_worktree_checkout_cb progress_cb;
8670 	void *progress_arg;
8671 	got_worktree_patch_cb patch_cb;
8672 	void *patch_arg;
8673 };
8674 
8675 static const struct got_error *
8676 create_unstaged_content(char **path_unstaged_content,
8677     char **path_new_staged_content, struct got_object_id *blob_id,
8678     struct got_object_id *staged_blob_id, const char *relpath,
8679     struct got_repository *repo,
8680     got_worktree_patch_cb patch_cb, void *patch_arg)
8681 {
8682 	const struct got_error *err, *free_err;
8683 	struct got_blob_object *blob = NULL, *staged_blob = NULL;
8684 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL, *rejectfile = NULL;
8685 	char *path1 = NULL, *path2 = NULL, *label1 = NULL;
8686 	struct got_diffreg_result *diffreg_result = NULL;
8687 	int line_cur1 = 1, line_cur2 = 1, n = 0, nchunks_used = 0;
8688 	int have_content = 0, have_rejected_content = 0, i = 0, nchanges = 0;
8689 	int fd1 = -1, fd2 = -1;
8690 
8691 	*path_unstaged_content = NULL;
8692 	*path_new_staged_content = NULL;
8693 
8694 	err = got_object_id_str(&label1, blob_id);
8695 	if (err)
8696 		return err;
8697 
8698 	fd1 = got_opentempfd();
8699 	if (fd1 == -1) {
8700 		err = got_error_from_errno("got_opentempfd");
8701 		goto done;
8702 	}
8703 	fd2 = got_opentempfd();
8704 	if (fd2 == -1) {
8705 		err = got_error_from_errno("got_opentempfd");
8706 		goto done;
8707 	}
8708 
8709 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192, fd1);
8710 	if (err)
8711 		goto done;
8712 
8713 	err = got_opentemp_named(&path1, &f1, "got-unstage-blob-base", "");
8714 	if (err)
8715 		goto done;
8716 
8717 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
8718 	if (err)
8719 		goto done;
8720 
8721 	err = got_object_open_as_blob(&staged_blob, repo, staged_blob_id, 8192,
8722 	    fd2);
8723 	if (err)
8724 		goto done;
8725 
8726 	err = got_opentemp_named(&path2, &f2, "got-unstage-blob-staged", "");
8727 	if (err)
8728 		goto done;
8729 
8730 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f2, staged_blob);
8731 	if (err)
8732 		goto done;
8733 
8734 	err = got_diff_files(&diffreg_result, f1, 1, label1, f2, 1,
8735 	    path2, 3, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
8736 	if (err)
8737 		goto done;
8738 
8739 	err = got_opentemp_named(path_unstaged_content, &outfile,
8740 	    "got-unstaged-content", "");
8741 	if (err)
8742 		goto done;
8743 	err = got_opentemp_named(path_new_staged_content, &rejectfile,
8744 	    "got-new-staged-content", "");
8745 	if (err)
8746 		goto done;
8747 
8748 	if (fseek(f1, 0L, SEEK_SET) == -1) {
8749 		err = got_ferror(f1, GOT_ERR_IO);
8750 		goto done;
8751 	}
8752 	if (fseek(f2, 0L, SEEK_SET) == -1) {
8753 		err = got_ferror(f2, GOT_ERR_IO);
8754 		goto done;
8755 	}
8756 	/* Count the number of actual changes in the diff result. */
8757 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
8758 		struct diff_chunk_context cc = {};
8759 		diff_chunk_context_load_change(&cc, &nchunks_used,
8760 		    diffreg_result->result, n, 0);
8761 		nchanges++;
8762 	}
8763 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
8764 		int choice;
8765 		err = apply_or_reject_change(&choice, &nchunks_used,
8766 		    diffreg_result->result, n, relpath, f1, f2,
8767 		    &line_cur1, &line_cur2,
8768 		    outfile, rejectfile, ++i, nchanges, patch_cb, patch_arg);
8769 		if (err)
8770 			goto done;
8771 		if (choice == GOT_PATCH_CHOICE_YES)
8772 			have_content = 1;
8773 		else
8774 			have_rejected_content = 1;
8775 		if (choice == GOT_PATCH_CHOICE_QUIT)
8776 			break;
8777 	}
8778 	if (have_content || have_rejected_content)
8779 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
8780 		    outfile, rejectfile);
8781 done:
8782 	free(label1);
8783 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
8784 		err = got_error_from_errno("close");
8785 	if (blob)
8786 		got_object_blob_close(blob);
8787 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
8788 		err = got_error_from_errno("close");
8789 	if (staged_blob)
8790 		got_object_blob_close(staged_blob);
8791 	free_err = got_diffreg_result_free(diffreg_result);
8792 	if (free_err && err == NULL)
8793 		err = free_err;
8794 	if (f1 && fclose(f1) == EOF && err == NULL)
8795 		err = got_error_from_errno2("fclose", path1);
8796 	if (f2 && fclose(f2) == EOF && err == NULL)
8797 		err = got_error_from_errno2("fclose", path2);
8798 	if (outfile && fclose(outfile) == EOF && err == NULL)
8799 		err = got_error_from_errno2("fclose", *path_unstaged_content);
8800 	if (rejectfile && fclose(rejectfile) == EOF && err == NULL)
8801 		err = got_error_from_errno2("fclose", *path_new_staged_content);
8802 	if (path1 && unlink(path1) == -1 && err == NULL)
8803 		err = got_error_from_errno2("unlink", path1);
8804 	if (path2 && unlink(path2) == -1 && err == NULL)
8805 		err = got_error_from_errno2("unlink", path2);
8806 	if (err || !have_content) {
8807 		if (*path_unstaged_content &&
8808 		    unlink(*path_unstaged_content) == -1 && err == NULL)
8809 			err = got_error_from_errno2("unlink",
8810 			    *path_unstaged_content);
8811 		free(*path_unstaged_content);
8812 		*path_unstaged_content = NULL;
8813 	}
8814 	if (err || !have_content || !have_rejected_content) {
8815 		if (*path_new_staged_content &&
8816 		    unlink(*path_new_staged_content) == -1 && err == NULL)
8817 			err = got_error_from_errno2("unlink",
8818 			    *path_new_staged_content);
8819 		free(*path_new_staged_content);
8820 		*path_new_staged_content = NULL;
8821 	}
8822 	free(path1);
8823 	free(path2);
8824 	return err;
8825 }
8826 
8827 static const struct got_error *
8828 unstage_hunks(struct got_object_id *staged_blob_id,
8829     struct got_blob_object *blob_base,
8830     struct got_object_id *blob_id, struct got_fileindex_entry *ie,
8831     const char *ondisk_path, const char *label_orig,
8832     struct got_worktree *worktree, struct got_repository *repo,
8833     got_worktree_patch_cb patch_cb, void *patch_arg,
8834     got_worktree_checkout_cb progress_cb, void *progress_arg)
8835 {
8836 	const struct got_error *err = NULL;
8837 	char *path_unstaged_content = NULL;
8838 	char *path_new_staged_content = NULL;
8839 	char *parent = NULL, *base_path = NULL;
8840 	char *blob_base_path = NULL;
8841 	struct got_object_id *new_staged_blob_id = NULL;
8842 	FILE *f = NULL, *f_base = NULL, *f_deriv2 = NULL;
8843 	struct stat sb;
8844 
8845 	err = create_unstaged_content(&path_unstaged_content,
8846 	    &path_new_staged_content, blob_id, staged_blob_id,
8847 	    ie->path, repo, patch_cb, patch_arg);
8848 	if (err)
8849 		return err;
8850 
8851 	if (path_unstaged_content == NULL)
8852 		return NULL;
8853 
8854 	if (path_new_staged_content) {
8855 		err = got_object_blob_create(&new_staged_blob_id,
8856 		    path_new_staged_content, repo);
8857 		if (err)
8858 			goto done;
8859 	}
8860 
8861 	f = fopen(path_unstaged_content, "re");
8862 	if (f == NULL) {
8863 		err = got_error_from_errno2("fopen",
8864 		    path_unstaged_content);
8865 		goto done;
8866 	}
8867 	if (fstat(fileno(f), &sb) == -1) {
8868 		err = got_error_from_errno2("fstat", path_unstaged_content);
8869 		goto done;
8870 	}
8871 	if (got_fileindex_entry_staged_filetype_get(ie) ==
8872 	    GOT_FILEIDX_MODE_SYMLINK && sb.st_size < PATH_MAX) {
8873 		char link_target[PATH_MAX];
8874 		size_t r;
8875 		r = fread(link_target, 1, sizeof(link_target), f);
8876 		if (r == 0 && ferror(f)) {
8877 			err = got_error_from_errno("fread");
8878 			goto done;
8879 		}
8880 		if (r >= sizeof(link_target)) { /* should not happen */
8881 			err = got_error(GOT_ERR_NO_SPACE);
8882 			goto done;
8883 		}
8884 		link_target[r] = '\0';
8885 		err = merge_symlink(worktree, blob_base,
8886 		    ondisk_path, ie->path, label_orig, link_target,
8887 		    worktree->base_commit_id, repo, progress_cb,
8888 		    progress_arg);
8889 	} else {
8890 		int local_changes_subsumed;
8891 
8892 		err = got_path_dirname(&parent, ondisk_path);
8893 		if (err)
8894 			return err;
8895 
8896 		if (asprintf(&base_path, "%s/got-unstage-blob-orig",
8897 		    parent) == -1) {
8898 			err = got_error_from_errno("asprintf");
8899 			base_path = NULL;
8900 			goto done;
8901 		}
8902 
8903 		err = got_opentemp_named(&blob_base_path, &f_base,
8904 		    base_path, "");
8905 		if (err)
8906 			goto done;
8907 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_base,
8908 		    blob_base);
8909 		if (err)
8910 			goto done;
8911 
8912 		/*
8913 		 * In order the run a 3-way merge with a symlink we copy the symlink's
8914 		 * target path into a temporary file and use that file with diff3.
8915 		 */
8916 		if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
8917 			err = dump_symlink_target_path_to_file(&f_deriv2,
8918 			    ondisk_path);
8919 			if (err)
8920 				goto done;
8921 		} else {
8922 			int fd;
8923 			fd = open(ondisk_path,
8924 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
8925 			if (fd == -1) {
8926 				err = got_error_from_errno2("open", ondisk_path);
8927 				goto done;
8928 			}
8929 			f_deriv2 = fdopen(fd, "r");
8930 			if (f_deriv2 == NULL) {
8931 				err = got_error_from_errno2("fdopen", ondisk_path);
8932 				close(fd);
8933 				goto done;
8934 			}
8935 		}
8936 
8937 		err = merge_file(&local_changes_subsumed, worktree,
8938 		    f_base, f, f_deriv2, ondisk_path, ie->path,
8939 		    got_fileindex_perms_to_st(ie),
8940 		    label_orig, "unstaged", NULL, GOT_DIFF_ALGORITHM_MYERS,
8941 		    repo, progress_cb, progress_arg);
8942 	}
8943 	if (err)
8944 		goto done;
8945 
8946 	if (new_staged_blob_id) {
8947 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
8948 		    SHA1_DIGEST_LENGTH);
8949 	} else {
8950 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
8951 		got_fileindex_entry_staged_filetype_set(ie, 0);
8952 	}
8953 done:
8954 	free(new_staged_blob_id);
8955 	if (path_unstaged_content &&
8956 	    unlink(path_unstaged_content) == -1 && err == NULL)
8957 		err = got_error_from_errno2("unlink", path_unstaged_content);
8958 	if (path_new_staged_content &&
8959 	    unlink(path_new_staged_content) == -1 && err == NULL)
8960 		err = got_error_from_errno2("unlink", path_new_staged_content);
8961 	if (blob_base_path && unlink(blob_base_path) == -1 && err == NULL)
8962 		err = got_error_from_errno2("unlink", blob_base_path);
8963 	if (f_base && fclose(f_base) == EOF && err == NULL)
8964 		err = got_error_from_errno2("fclose", path_unstaged_content);
8965 	if (f && fclose(f) == EOF && err == NULL)
8966 		err = got_error_from_errno2("fclose", path_unstaged_content);
8967 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
8968 		err = got_error_from_errno2("fclose", ondisk_path);
8969 	free(path_unstaged_content);
8970 	free(path_new_staged_content);
8971 	free(blob_base_path);
8972 	free(parent);
8973 	free(base_path);
8974 	return err;
8975 }
8976 
8977 static const struct got_error *
8978 unstage_path(void *arg, unsigned char status,
8979     unsigned char staged_status, const char *relpath,
8980     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8981     struct got_object_id *commit_id, int dirfd, const char *de_name)
8982 {
8983 	const struct got_error *err = NULL;
8984 	struct unstage_path_arg *a = arg;
8985 	struct got_fileindex_entry *ie;
8986 	struct got_blob_object *blob_base = NULL, *blob_staged = NULL;
8987 	char *ondisk_path = NULL;
8988 	char *id_str = NULL, *label_orig = NULL;
8989 	int local_changes_subsumed;
8990 	struct stat sb;
8991 	int fd1 = -1, fd2 = -1;
8992 
8993 	if (staged_status != GOT_STATUS_ADD &&
8994 	    staged_status != GOT_STATUS_MODIFY &&
8995 	    staged_status != GOT_STATUS_DELETE)
8996 		return NULL;
8997 
8998 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8999 	if (ie == NULL)
9000 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
9001 
9002 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, relpath)
9003 	    == -1)
9004 		return got_error_from_errno("asprintf");
9005 
9006 	err = got_object_id_str(&id_str,
9007 	    commit_id ? commit_id : a->worktree->base_commit_id);
9008 	if (err)
9009 		goto done;
9010 	if (asprintf(&label_orig, "%s: commit %s", GOT_MERGE_LABEL_BASE,
9011 	    id_str) == -1) {
9012 		err = got_error_from_errno("asprintf");
9013 		goto done;
9014 	}
9015 
9016 	fd1 = got_opentempfd();
9017 	if (fd1 == -1) {
9018 		err = got_error_from_errno("got_opentempfd");
9019 		goto done;
9020 	}
9021 	fd2 = got_opentempfd();
9022 	if (fd2 == -1) {
9023 		err = got_error_from_errno("got_opentempfd");
9024 		goto done;
9025 	}
9026 
9027 	switch (staged_status) {
9028 	case GOT_STATUS_MODIFY:
9029 		err = got_object_open_as_blob(&blob_base, a->repo,
9030 		    blob_id, 8192, fd1);
9031 		if (err)
9032 			break;
9033 		/* fall through */
9034 	case GOT_STATUS_ADD:
9035 		if (a->patch_cb) {
9036 			if (staged_status == GOT_STATUS_ADD) {
9037 				int choice = GOT_PATCH_CHOICE_NONE;
9038 				err = (*a->patch_cb)(&choice, a->patch_arg,
9039 				    staged_status, ie->path, NULL, 1, 1);
9040 				if (err)
9041 					break;
9042 				if (choice != GOT_PATCH_CHOICE_YES)
9043 					break;
9044 			} else {
9045 				err = unstage_hunks(staged_blob_id,
9046 				    blob_base, blob_id, ie, ondisk_path,
9047 				    label_orig, a->worktree, a->repo,
9048 				    a->patch_cb, a->patch_arg,
9049 				    a->progress_cb, a->progress_arg);
9050 				break; /* Done with this file. */
9051 			}
9052 		}
9053 		err = got_object_open_as_blob(&blob_staged, a->repo,
9054 		    staged_blob_id, 8192, fd2);
9055 		if (err)
9056 			break;
9057 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
9058 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
9059 		case GOT_FILEIDX_MODE_REGULAR_FILE:
9060 			err = merge_blob(&local_changes_subsumed, a->worktree,
9061 			    blob_base, ondisk_path, relpath,
9062 			    got_fileindex_perms_to_st(ie), label_orig,
9063 			    blob_staged, commit_id ? commit_id :
9064 			    a->worktree->base_commit_id, a->repo,
9065 			    a->progress_cb, a->progress_arg);
9066 			break;
9067 		case GOT_FILEIDX_MODE_SYMLINK:
9068 			if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
9069 				char *staged_target;
9070 				err = got_object_blob_read_to_str(
9071 				    &staged_target, blob_staged);
9072 				if (err)
9073 					goto done;
9074 				err = merge_symlink(a->worktree, blob_base,
9075 				    ondisk_path, relpath, label_orig,
9076 				    staged_target, commit_id ? commit_id :
9077 				    a->worktree->base_commit_id,
9078 				    a->repo, a->progress_cb, a->progress_arg);
9079 				free(staged_target);
9080 			} else {
9081 				err = merge_blob(&local_changes_subsumed,
9082 				    a->worktree, blob_base, ondisk_path,
9083 				    relpath, got_fileindex_perms_to_st(ie),
9084 				    label_orig, blob_staged,
9085 				    commit_id ? commit_id :
9086 				    a->worktree->base_commit_id, a->repo,
9087 				    a->progress_cb, a->progress_arg);
9088 			}
9089 			break;
9090 		default:
9091 			err = got_error_path(relpath, GOT_ERR_BAD_FILETYPE);
9092 			break;
9093 		}
9094 		if (err == NULL) {
9095 			got_fileindex_entry_stage_set(ie,
9096 			    GOT_FILEIDX_STAGE_NONE);
9097 			got_fileindex_entry_staged_filetype_set(ie, 0);
9098 		}
9099 		break;
9100 	case GOT_STATUS_DELETE:
9101 		if (a->patch_cb) {
9102 			int choice = GOT_PATCH_CHOICE_NONE;
9103 			err = (*a->patch_cb)(&choice, a->patch_arg,
9104 			    staged_status, ie->path, NULL, 1, 1);
9105 			if (err)
9106 				break;
9107 			if (choice == GOT_PATCH_CHOICE_NO)
9108 				break;
9109 			if (choice != GOT_PATCH_CHOICE_YES) {
9110 				err = got_error(GOT_ERR_PATCH_CHOICE);
9111 				break;
9112 			}
9113 		}
9114 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
9115 		got_fileindex_entry_staged_filetype_set(ie, 0);
9116 		err = get_file_status(&status, &sb, ie, ondisk_path,
9117 		    dirfd, de_name, a->repo);
9118 		if (err)
9119 			break;
9120 		err = (*a->progress_cb)(a->progress_arg, status, relpath);
9121 		break;
9122 	}
9123 done:
9124 	free(ondisk_path);
9125 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
9126 		err = got_error_from_errno("close");
9127 	if (blob_base)
9128 		got_object_blob_close(blob_base);
9129 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
9130 		err = got_error_from_errno("close");
9131 	if (blob_staged)
9132 		got_object_blob_close(blob_staged);
9133 	free(id_str);
9134 	free(label_orig);
9135 	return err;
9136 }
9137 
9138 const struct got_error *
9139 got_worktree_unstage(struct got_worktree *worktree,
9140     struct got_pathlist_head *paths,
9141     got_worktree_checkout_cb progress_cb, void *progress_arg,
9142     got_worktree_patch_cb patch_cb, void *patch_arg,
9143     struct got_repository *repo)
9144 {
9145 	const struct got_error *err = NULL, *sync_err, *unlockerr;
9146 	struct got_pathlist_entry *pe;
9147 	struct got_fileindex *fileindex = NULL;
9148 	char *fileindex_path = NULL;
9149 	struct unstage_path_arg upa;
9150 
9151 	err = lock_worktree(worktree, LOCK_EX);
9152 	if (err)
9153 		return err;
9154 
9155 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
9156 	if (err)
9157 		goto done;
9158 
9159 	upa.worktree = worktree;
9160 	upa.fileindex = fileindex;
9161 	upa.repo = repo;
9162 	upa.progress_cb = progress_cb;
9163 	upa.progress_arg = progress_arg;
9164 	upa.patch_cb = patch_cb;
9165 	upa.patch_arg = patch_arg;
9166 	TAILQ_FOREACH(pe, paths, entry) {
9167 		err = worktree_status(worktree, pe->path, fileindex, repo,
9168 		    unstage_path, &upa, NULL, NULL, 1, 0);
9169 		if (err)
9170 			goto done;
9171 	}
9172 
9173 	sync_err = sync_fileindex(fileindex, fileindex_path);
9174 	if (sync_err && err == NULL)
9175 		err = sync_err;
9176 done:
9177 	free(fileindex_path);
9178 	if (fileindex)
9179 		got_fileindex_free(fileindex);
9180 	unlockerr = lock_worktree(worktree, LOCK_SH);
9181 	if (unlockerr && err == NULL)
9182 		err = unlockerr;
9183 	return err;
9184 }
9185 
9186 struct report_file_info_arg {
9187 	struct got_worktree *worktree;
9188 	got_worktree_path_info_cb info_cb;
9189 	void *info_arg;
9190 	struct got_pathlist_head *paths;
9191 	got_cancel_cb cancel_cb;
9192 	void *cancel_arg;
9193 };
9194 
9195 static const struct got_error *
9196 report_file_info(void *arg, struct got_fileindex_entry *ie)
9197 {
9198 	struct report_file_info_arg *a = arg;
9199 	struct got_pathlist_entry *pe;
9200 	struct got_object_id blob_id, staged_blob_id, commit_id;
9201 	struct got_object_id *blob_idp = NULL, *staged_blob_idp = NULL;
9202 	struct got_object_id *commit_idp = NULL;
9203 	int stage;
9204 
9205 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
9206 		return got_error(GOT_ERR_CANCELLED);
9207 
9208 	TAILQ_FOREACH(pe, a->paths, entry) {
9209 		if (pe->path_len == 0 || strcmp(pe->path, ie->path) == 0 ||
9210 		    got_path_is_child(ie->path, pe->path, pe->path_len))
9211 			break;
9212 	}
9213 	if (pe == NULL) /* not found */
9214 		return NULL;
9215 
9216 	if (got_fileindex_entry_has_blob(ie))
9217 		blob_idp = got_fileindex_entry_get_blob_id(&blob_id, ie);
9218 	stage = got_fileindex_entry_stage_get(ie);
9219 	if (stage == GOT_FILEIDX_STAGE_MODIFY ||
9220 	    stage == GOT_FILEIDX_STAGE_ADD) {
9221 		staged_blob_idp = got_fileindex_entry_get_staged_blob_id(
9222 		    &staged_blob_id, ie);
9223 	}
9224 
9225 	if (got_fileindex_entry_has_commit(ie))
9226 		commit_idp = got_fileindex_entry_get_commit_id(&commit_id, ie);
9227 
9228 	return a->info_cb(a->info_arg, ie->path, got_fileindex_perms_to_st(ie),
9229 	    (time_t)ie->mtime_sec, blob_idp, staged_blob_idp, commit_idp);
9230 }
9231 
9232 const struct got_error *
9233 got_worktree_path_info(struct got_worktree *worktree,
9234     struct got_pathlist_head *paths,
9235     got_worktree_path_info_cb info_cb, void *info_arg,
9236     got_cancel_cb cancel_cb, void *cancel_arg)
9237 
9238 {
9239 	const struct got_error *err = NULL, *unlockerr;
9240 	struct got_fileindex *fileindex = NULL;
9241 	char *fileindex_path = NULL;
9242 	struct report_file_info_arg arg;
9243 
9244 	err = lock_worktree(worktree, LOCK_SH);
9245 	if (err)
9246 		return err;
9247 
9248 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
9249 	if (err)
9250 		goto done;
9251 
9252 	arg.worktree = worktree;
9253 	arg.info_cb = info_cb;
9254 	arg.info_arg = info_arg;
9255 	arg.paths = paths;
9256 	arg.cancel_cb = cancel_cb;
9257 	arg.cancel_arg = cancel_arg;
9258 	err = got_fileindex_for_each_entry_safe(fileindex, report_file_info,
9259 	    &arg);
9260 done:
9261 	free(fileindex_path);
9262 	if (fileindex)
9263 		got_fileindex_free(fileindex);
9264 	unlockerr = lock_worktree(worktree, LOCK_UN);
9265 	if (unlockerr && err == NULL)
9266 		err = unlockerr;
9267 	return err;
9268 }
9269 
9270 static const struct got_error *
9271 patch_check_path(const char *p, char **path, unsigned char *status,
9272     unsigned char *staged_status, struct got_fileindex *fileindex,
9273     struct got_worktree *worktree, struct got_repository *repo)
9274 {
9275 	const struct got_error *err;
9276 	struct got_fileindex_entry *ie;
9277 	struct stat sb;
9278 	char *ondisk_path = NULL;
9279 
9280 	err = got_worktree_resolve_path(path, worktree, p);
9281 	if (err)
9282 		return err;
9283 
9284 	if (asprintf(&ondisk_path, "%s%s%s", worktree->root_path,
9285 	    *path[0] ? "/" : "", *path) == -1)
9286 		return got_error_from_errno("asprintf");
9287 
9288 	ie = got_fileindex_entry_get(fileindex, *path, strlen(*path));
9289 	if (ie) {
9290 		*staged_status = get_staged_status(ie);
9291 		err = get_file_status(status, &sb, ie, ondisk_path, -1, NULL,
9292 		    repo);
9293 		if (err)
9294 			goto done;
9295 	} else {
9296 		*staged_status = GOT_STATUS_NO_CHANGE;
9297 		*status = GOT_STATUS_UNVERSIONED;
9298 		if (lstat(ondisk_path, &sb) == -1) {
9299 			if (errno != ENOENT) {
9300 				err = got_error_from_errno2("lstat",
9301 				    ondisk_path);
9302 				goto done;
9303 			}
9304 			*status = GOT_STATUS_NONEXISTENT;
9305 		}
9306 	}
9307 
9308 done:
9309 	free(ondisk_path);
9310 	return err;
9311 }
9312 
9313 static const struct got_error *
9314 patch_can_rm(const char *path, unsigned char status,
9315     unsigned char staged_status)
9316 {
9317 	if (status == GOT_STATUS_NONEXISTENT)
9318 		return got_error_set_errno(ENOENT, path);
9319 	if (status != GOT_STATUS_NO_CHANGE &&
9320 	    status != GOT_STATUS_ADD &&
9321 	    status != GOT_STATUS_MODIFY &&
9322 	    status != GOT_STATUS_MODE_CHANGE)
9323 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9324 	if (staged_status == GOT_STATUS_DELETE)
9325 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9326 	return NULL;
9327 }
9328 
9329 static const struct got_error *
9330 patch_can_add(const char *path, unsigned char status)
9331 {
9332 	if (status != GOT_STATUS_NONEXISTENT)
9333 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9334 	return NULL;
9335 }
9336 
9337 static const struct got_error *
9338 patch_can_edit(const char *path, unsigned char status,
9339     unsigned char staged_status)
9340 {
9341 	if (status == GOT_STATUS_NONEXISTENT)
9342 		return got_error_set_errno(ENOENT, path);
9343 	if (status != GOT_STATUS_NO_CHANGE &&
9344 	    status != GOT_STATUS_ADD &&
9345 	    status != GOT_STATUS_MODIFY)
9346 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9347 	if (staged_status == GOT_STATUS_DELETE)
9348 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9349 	return NULL;
9350 }
9351 
9352 const struct got_error *
9353 got_worktree_patch_prepare(struct got_fileindex **fileindex,
9354     char **fileindex_path, struct got_worktree *worktree)
9355 {
9356 	return open_fileindex(fileindex, fileindex_path, worktree);
9357 }
9358 
9359 const struct got_error *
9360 got_worktree_patch_check_path(const char *old, const char *new,
9361     char **oldpath, char **newpath, struct got_worktree *worktree,
9362     struct got_repository *repo, struct got_fileindex *fileindex)
9363 {
9364 	const struct got_error *err = NULL;
9365 	int file_renamed = 0;
9366 	unsigned char status_old, staged_status_old;
9367 	unsigned char status_new, staged_status_new;
9368 
9369 	*oldpath = NULL;
9370 	*newpath = NULL;
9371 
9372 	err = patch_check_path(old != NULL ? old : new, oldpath,
9373 	    &status_old, &staged_status_old, fileindex, worktree, repo);
9374 	if (err)
9375 		goto done;
9376 
9377 	err = patch_check_path(new != NULL ? new : old, newpath,
9378 	    &status_new, &staged_status_new, fileindex, worktree, repo);
9379 	if (err)
9380 		goto done;
9381 
9382 	if (old != NULL && new != NULL && strcmp(old, new) != 0)
9383 		file_renamed = 1;
9384 
9385 	if (old != NULL && new == NULL)
9386 		err = patch_can_rm(*oldpath, status_old, staged_status_old);
9387 	else if (file_renamed) {
9388 		err = patch_can_rm(*oldpath, status_old, staged_status_old);
9389 		if (err == NULL)
9390 			err = patch_can_add(*newpath, status_new);
9391 	} else if (old == NULL)
9392 		err = patch_can_add(*newpath, status_new);
9393 	else
9394 		err = patch_can_edit(*newpath, status_new, staged_status_new);
9395 
9396 done:
9397 	if (err) {
9398 		free(*oldpath);
9399 		*oldpath = NULL;
9400 		free(*newpath);
9401 		*newpath = NULL;
9402 	}
9403 	return err;
9404 }
9405 
9406 const struct got_error *
9407 got_worktree_patch_schedule_add(const char *path, struct got_repository *repo,
9408     struct got_worktree *worktree, struct got_fileindex *fileindex,
9409     got_worktree_checkout_cb progress_cb, void *progress_arg)
9410 {
9411 	struct schedule_addition_args saa;
9412 
9413 	memset(&saa, 0, sizeof(saa));
9414 	saa.worktree = worktree;
9415 	saa.fileindex = fileindex;
9416 	saa.progress_cb = progress_cb;
9417 	saa.progress_arg = progress_arg;
9418 	saa.repo = repo;
9419 
9420 	return worktree_status(worktree, path, fileindex, repo,
9421 	    schedule_addition, &saa, NULL, NULL, 1, 0);
9422 }
9423 
9424 const struct got_error *
9425 got_worktree_patch_schedule_rm(const char *path, struct got_repository *repo,
9426     struct got_worktree *worktree, struct got_fileindex *fileindex,
9427     got_worktree_delete_cb progress_cb, void *progress_arg)
9428 {
9429 	struct schedule_deletion_args sda;
9430 
9431 	memset(&sda, 0, sizeof(sda));
9432 	sda.worktree = worktree;
9433 	sda.fileindex = fileindex;
9434 	sda.progress_cb = progress_cb;
9435 	sda.progress_arg = progress_arg;
9436 	sda.repo = repo;
9437 	sda.delete_local_mods = 0;
9438 	sda.keep_on_disk = 0;
9439 	sda.ignore_missing_paths = 0;
9440 	sda.status_codes = NULL;
9441 
9442 	return worktree_status(worktree, path, fileindex, repo,
9443 	    schedule_for_deletion, &sda, NULL, NULL, 1, 1);
9444 }
9445 
9446 const struct got_error *
9447 got_worktree_patch_complete(struct got_fileindex *fileindex,
9448     const char *fileindex_path)
9449 {
9450 	const struct got_error *err = NULL;
9451 
9452 	err = sync_fileindex(fileindex, fileindex_path);
9453 	got_fileindex_free(fileindex);
9454 
9455 	return err;
9456 }