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 <sha2.h>
33 #include <zlib.h>
34 #include <fnmatch.h>
35 #include <libgen.h>
36 #include <uuid.h>
37 #include <util.h>
38 
39 #include "got_error.h"
40 #include "got_repository.h"
41 #include "got_reference.h"
42 #include "got_object.h"
43 #include "got_path.h"
44 #include "got_cancel.h"
45 #include "got_worktree.h"
46 #include "got_opentemp.h"
47 #include "got_diff.h"
48 
49 #include "got_lib_worktree.h"
50 #include "got_lib_hash.h"
51 #include "got_lib_fileindex.h"
52 #include "got_lib_inflate.h"
53 #include "got_lib_delta.h"
54 #include "got_lib_object.h"
55 #include "got_lib_object_parse.h"
56 #include "got_lib_object_create.h"
57 #include "got_lib_object_idset.h"
58 #include "got_lib_diff.h"
59 #include "got_lib_gotconfig.h"
60 
61 #ifndef MIN
62 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
63 #endif
64 
65 #define GOT_MERGE_LABEL_MERGED	"merged change"
66 #define GOT_MERGE_LABEL_BASE	"3-way merge base"
67 
68 static mode_t		 apply_umask(mode_t);
69 
70 static const struct got_error *
71 create_meta_file(const char *path_got, const char *name, const char *content)
72 {
73 	const struct got_error *err = NULL;
74 	char *path;
75 
76 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
77 		return got_error_from_errno("asprintf");
78 
79 	err = got_path_create_file(path, content);
80 	free(path);
81 	return err;
82 }
83 
84 static const struct got_error *
85 update_meta_file(const char *path_got, const char *name, const char *content)
86 {
87 	const struct got_error *err = NULL;
88 	FILE *tmpfile = NULL;
89 	char *tmppath = NULL;
90 	char *path = NULL;
91 
92 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
93 		err = got_error_from_errno("asprintf");
94 		path = NULL;
95 		goto done;
96 	}
97 
98 	err = got_opentemp_named(&tmppath, &tmpfile, path, "");
99 	if (err)
100 		goto done;
101 
102 	if (content) {
103 		int len = fprintf(tmpfile, "%s\n", content);
104 		if (len != strlen(content) + 1) {
105 			err = got_error_from_errno2("fprintf", tmppath);
106 			goto done;
107 		}
108 	}
109 
110 	if (rename(tmppath, path) != 0) {
111 		err = got_error_from_errno3("rename", tmppath, path);
112 		unlink(tmppath);
113 		goto done;
114 	}
115 
116 done:
117 	if (fclose(tmpfile) == EOF && err == NULL)
118 		err = got_error_from_errno2("fclose", tmppath);
119 	free(tmppath);
120 	return err;
121 }
122 
123 static const struct got_error *
124 write_head_ref(const char *path_got, struct got_reference *head_ref)
125 {
126 	const struct got_error *err = NULL;
127 	char *refstr = NULL;
128 
129 	if (got_ref_is_symbolic(head_ref)) {
130 		refstr = got_ref_to_str(head_ref);
131 		if (refstr == NULL)
132 			return got_error_from_errno("got_ref_to_str");
133 	} else {
134 		refstr = strdup(got_ref_get_name(head_ref));
135 		if (refstr == NULL)
136 			return got_error_from_errno("strdup");
137 	}
138 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
139 	free(refstr);
140 	return err;
141 }
142 
143 const struct got_error *
144 got_worktree_init(const char *path, struct got_reference *head_ref,
145     const char *prefix, struct got_repository *repo)
146 {
147 	const struct got_error *err = NULL;
148 	struct got_object_id *commit_id = NULL;
149 	uuid_t uuid;
150 	uint32_t uuid_status;
151 	int obj_type;
152 	char *path_got = NULL;
153 	char *formatstr = NULL;
154 	char *absprefix = NULL;
155 	char *basestr = NULL;
156 	char *uuidstr = NULL;
157 
158 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
159 		err = got_error(GOT_ERR_WORKTREE_REPO);
160 		goto done;
161 	}
162 
163 	err = got_ref_resolve(&commit_id, repo, head_ref);
164 	if (err)
165 		return err;
166 	err = got_object_get_type(&obj_type, repo, commit_id);
167 	if (err)
168 		return err;
169 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
170 		return got_error(GOT_ERR_OBJ_TYPE);
171 
172 	if (!got_path_is_absolute(prefix)) {
173 		if (asprintf(&absprefix, "/%s", prefix) == -1)
174 			return got_error_from_errno("asprintf");
175 	}
176 
177 	/* Create top-level directory (may already exist). */
178 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
179 		err = got_error_from_errno2("mkdir", path);
180 		goto done;
181 	}
182 
183 	/* Create .got directory (may already exist). */
184 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
185 		err = got_error_from_errno("asprintf");
186 		goto done;
187 	}
188 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
189 		err = got_error_from_errno2("mkdir", path_got);
190 		goto done;
191 	}
192 
193 	/* Create an empty lock file. */
194 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
195 	if (err)
196 		goto done;
197 
198 	/* Create an empty file index. */
199 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
200 	if (err)
201 		goto done;
202 
203 	/* Write the HEAD reference. */
204 	err = write_head_ref(path_got, head_ref);
205 	if (err)
206 		goto done;
207 
208 	/* Record our base commit. */
209 	err = got_object_id_str(&basestr, commit_id);
210 	if (err)
211 		goto done;
212 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
213 	if (err)
214 		goto done;
215 
216 	/* Store path to repository. */
217 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
218 	    got_repo_get_path(repo));
219 	if (err)
220 		goto done;
221 
222 	/* Store in-repository path prefix. */
223 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
224 	    absprefix ? absprefix : prefix);
225 	if (err)
226 		goto done;
227 
228 	/* Generate UUID. */
229 	uuid_create(&uuid, &uuid_status);
230 	if (uuid_status != uuid_s_ok) {
231 		err = got_error_uuid(uuid_status, "uuid_create");
232 		goto done;
233 	}
234 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
235 	if (uuid_status != uuid_s_ok) {
236 		err = got_error_uuid(uuid_status, "uuid_to_string");
237 		goto done;
238 	}
239 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
240 	if (err)
241 		goto done;
242 
243 	/* Stamp work tree with format file. */
244 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
245 		err = got_error_from_errno("asprintf");
246 		goto done;
247 	}
248 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
249 	if (err)
250 		goto done;
251 
252 done:
253 	free(commit_id);
254 	free(path_got);
255 	free(formatstr);
256 	free(absprefix);
257 	free(basestr);
258 	free(uuidstr);
259 	return err;
260 }
261 
262 const struct got_error *
263 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
264     const char *path_prefix)
265 {
266 	char *absprefix = NULL;
267 
268 	if (!got_path_is_absolute(path_prefix)) {
269 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
270 			return got_error_from_errno("asprintf");
271 	}
272 	*match = (strcmp(absprefix ? absprefix : path_prefix,
273 	    worktree->path_prefix) == 0);
274 	free(absprefix);
275 	return NULL;
276 }
277 
278 const char *
279 got_worktree_get_head_ref_name(struct got_worktree *worktree)
280 {
281 	return worktree->head_ref_name;
282 }
283 
284 const struct got_error *
285 got_worktree_set_head_ref(struct got_worktree *worktree,
286     struct got_reference *head_ref)
287 {
288 	const struct got_error *err = NULL;
289 	char *path_got = NULL, *head_ref_name = NULL;
290 
291 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
292 	    GOT_WORKTREE_GOT_DIR) == -1) {
293 		err = got_error_from_errno("asprintf");
294 		path_got = NULL;
295 		goto done;
296 	}
297 
298 	head_ref_name = strdup(got_ref_get_name(head_ref));
299 	if (head_ref_name == NULL) {
300 		err = got_error_from_errno("strdup");
301 		goto done;
302 	}
303 
304 	err = write_head_ref(path_got, head_ref);
305 	if (err)
306 		goto done;
307 
308 	free(worktree->head_ref_name);
309 	worktree->head_ref_name = head_ref_name;
310 done:
311 	free(path_got);
312 	if (err)
313 		free(head_ref_name);
314 	return err;
315 }
316 
317 struct got_object_id *
318 got_worktree_get_base_commit_id(struct got_worktree *worktree)
319 {
320 	return worktree->base_commit_id;
321 }
322 
323 const struct got_error *
324 got_worktree_set_base_commit_id(struct got_worktree *worktree,
325     struct got_repository *repo, struct got_object_id *commit_id)
326 {
327 	const struct got_error *err;
328 	struct got_object *obj = NULL;
329 	char *id_str = NULL;
330 	char *path_got = NULL;
331 
332 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
333 	    GOT_WORKTREE_GOT_DIR) == -1) {
334 		err = got_error_from_errno("asprintf");
335 		path_got = NULL;
336 		goto done;
337 	}
338 
339 	err = got_object_open(&obj, repo, commit_id);
340 	if (err)
341 		return err;
342 
343 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
344 		err = got_error(GOT_ERR_OBJ_TYPE);
345 		goto done;
346 	}
347 
348 	/* Record our base commit. */
349 	err = got_object_id_str(&id_str, commit_id);
350 	if (err)
351 		goto done;
352 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
353 	if (err)
354 		goto done;
355 
356 	free(worktree->base_commit_id);
357 	worktree->base_commit_id = got_object_id_dup(commit_id);
358 	if (worktree->base_commit_id == NULL) {
359 		err = got_error_from_errno("got_object_id_dup");
360 		goto done;
361 	}
362 done:
363 	if (obj)
364 		got_object_close(obj);
365 	free(id_str);
366 	free(path_got);
367 	return err;
368 }
369 
370 const struct got_gotconfig *
371 got_worktree_get_gotconfig(struct got_worktree *worktree)
372 {
373 	return worktree->gotconfig;
374 }
375 
376 static const struct got_error *
377 lock_worktree(struct got_worktree *worktree, int operation)
378 {
379 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
380 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
381 		    : got_error_from_errno2("flock",
382 		    got_worktree_get_root_path(worktree)));
383 	return NULL;
384 }
385 
386 static const struct got_error *
387 add_dir_on_disk(struct got_worktree *worktree, const char *path)
388 {
389 	const struct got_error *err = NULL;
390 	char *abspath;
391 
392 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
393 		return got_error_from_errno("asprintf");
394 
395 	err = got_path_mkdir(abspath);
396 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
397 		struct stat sb;
398 		err = NULL;
399 		if (lstat(abspath, &sb) == -1) {
400 			err = got_error_from_errno2("lstat", abspath);
401 		} else if (!S_ISDIR(sb.st_mode)) {
402 			/* TODO directory is obstructed; do something */
403 			err = got_error_path(abspath, GOT_ERR_FILE_OBSTRUCTED);
404 		}
405 	}
406 	free(abspath);
407 	return err;
408 }
409 
410 static const struct got_error *
411 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
412 {
413 	const struct got_error *err = NULL;
414 	uint8_t fbuf1[8192];
415 	uint8_t fbuf2[8192];
416 	size_t flen1 = 0, flen2 = 0;
417 
418 	*same = 1;
419 
420 	for (;;) {
421 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
422 		if (flen1 == 0 && ferror(f1)) {
423 			err = got_error_from_errno("fread");
424 			break;
425 		}
426 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
427 		if (flen2 == 0 && ferror(f2)) {
428 			err = got_error_from_errno("fread");
429 			break;
430 		}
431 		if (flen1 == 0) {
432 			if (flen2 != 0)
433 				*same = 0;
434 			break;
435 		} else if (flen2 == 0) {
436 			if (flen1 != 0)
437 				*same = 0;
438 			break;
439 		} else if (flen1 == flen2) {
440 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
441 				*same = 0;
442 				break;
443 			}
444 		} else {
445 			*same = 0;
446 			break;
447 		}
448 	}
449 
450 	return err;
451 }
452 
453 static const struct got_error *
454 check_files_equal(int *same, FILE *f1, FILE *f2)
455 {
456 	struct stat sb;
457 	size_t size1, size2;
458 
459 	*same = 1;
460 
461 	if (fstat(fileno(f1), &sb) != 0)
462 		return got_error_from_errno("fstat");
463 	size1 = sb.st_size;
464 
465 	if (fstat(fileno(f2), &sb) != 0)
466 		return got_error_from_errno("fstat");
467 	size2 = sb.st_size;
468 
469 	if (size1 != size2) {
470 		*same = 0;
471 		return NULL;
472 	}
473 
474 	if (fseek(f1, 0L, SEEK_SET) == -1)
475 		return got_ferror(f1, GOT_ERR_IO);
476 	if (fseek(f2, 0L, SEEK_SET) == -1)
477 		return got_ferror(f2, GOT_ERR_IO);
478 
479 	return check_file_contents_equal(same, f1, f2);
480 }
481 
482 static const struct got_error *
483 copy_file_to_fd(off_t *outsize, FILE *f, int outfd)
484 {
485 	uint8_t fbuf[65536];
486 	size_t flen;
487 	ssize_t outlen;
488 
489 	*outsize = 0;
490 
491 	if (fseek(f, 0L, SEEK_SET) == -1)
492 		return got_ferror(f, GOT_ERR_IO);
493 
494 	for (;;) {
495 		flen = fread(fbuf, 1, sizeof(fbuf), f);
496 		if (flen == 0) {
497 			if (ferror(f))
498 				return got_error_from_errno("fread");
499 			if (feof(f))
500 				break;
501 		}
502 		outlen = write(outfd, fbuf, flen);
503 		if (outlen == -1)
504 			return got_error_from_errno("write");
505 		if (outlen != flen)
506 			return got_error(GOT_ERR_IO);
507 		*outsize += outlen;
508 	}
509 
510 	return NULL;
511 }
512 
513 static const struct got_error *
514 merge_binary_file(int *overlapcnt, int merged_fd,
515     FILE *f_deriv, FILE *f_orig, FILE *f_deriv2,
516     const char *label_deriv, const char *label_orig, const char *label_deriv2,
517     const char *ondisk_path)
518 {
519 	const struct got_error *err = NULL;
520 	int same_content, changed_deriv, changed_deriv2;
521 	int fd_orig = -1, fd_deriv = -1, fd_deriv2 = -1;
522 	off_t size_orig = 0, size_deriv = 0, size_deriv2 = 0;
523 	char *path_orig = NULL, *path_deriv = NULL, *path_deriv2 = NULL;
524 	char *base_path_orig = NULL, *base_path_deriv = NULL;
525 	char *base_path_deriv2 = NULL;
526 
527 	*overlapcnt = 0;
528 
529 	err = check_files_equal(&same_content, f_deriv, f_deriv2);
530 	if (err)
531 		return err;
532 
533 	if (same_content)
534 		return copy_file_to_fd(&size_deriv, f_deriv, merged_fd);
535 
536 	err = check_files_equal(&same_content, f_deriv, f_orig);
537 	if (err)
538 		return err;
539 	changed_deriv = !same_content;
540 	err = check_files_equal(&same_content, f_deriv2, f_orig);
541 	if (err)
542 		return err;
543 	changed_deriv2 = !same_content;
544 
545 	if (changed_deriv && changed_deriv2) {
546 		*overlapcnt = 1;
547 		if (asprintf(&base_path_orig, "%s-orig", ondisk_path) == -1) {
548 			err = got_error_from_errno("asprintf");
549 			goto done;
550 		}
551 		if (asprintf(&base_path_deriv, "%s-1", ondisk_path) == -1) {
552 			err = got_error_from_errno("asprintf");
553 			goto done;
554 		}
555 		if (asprintf(&base_path_deriv2, "%s-2", ondisk_path) == -1) {
556 			err = got_error_from_errno("asprintf");
557 			goto done;
558 		}
559 		err = got_opentemp_named_fd(&path_orig, &fd_orig,
560 		    base_path_orig, "");
561 		if (err)
562 			goto done;
563 		err = got_opentemp_named_fd(&path_deriv, &fd_deriv,
564 		    base_path_deriv, "");
565 		if (err)
566 			goto done;
567 		err = got_opentemp_named_fd(&path_deriv2, &fd_deriv2,
568 		    base_path_deriv2, "");
569 		if (err)
570 			goto done;
571 		err = copy_file_to_fd(&size_orig, f_orig, fd_orig);
572 		if (err)
573 			goto done;
574 		err = copy_file_to_fd(&size_deriv, f_deriv, fd_deriv);
575 		if (err)
576 			goto done;
577 		err = copy_file_to_fd(&size_deriv2, f_deriv2, fd_deriv2);
578 		if (err)
579 			goto done;
580 		if (dprintf(merged_fd, "Binary files differ and cannot be "
581 		    "merged automatically:\n") < 0) {
582 			err = got_error_from_errno("dprintf");
583 			goto done;
584 		}
585 		if (dprintf(merged_fd, "%s%s%s\nfile %s\n",
586 		    GOT_DIFF_CONFLICT_MARKER_BEGIN,
587 		    label_deriv ? " " : "",
588 		    label_deriv ? label_deriv : "",
589 		    path_deriv) < 0) {
590 			err = got_error_from_errno("dprintf");
591 			goto done;
592 		}
593 		if (size_orig > 0) {
594 			if (dprintf(merged_fd, "%s%s%s\nfile %s\n",
595 			    GOT_DIFF_CONFLICT_MARKER_ORIG,
596 			    label_orig ? " " : "",
597 			    label_orig ? label_orig : "",
598 			    path_orig) < 0) {
599 				err = got_error_from_errno("dprintf");
600 				goto done;
601 			}
602 		}
603 		if (dprintf(merged_fd, "%s\nfile %s\n%s%s%s\n",
604 		    GOT_DIFF_CONFLICT_MARKER_SEP,
605 		    path_deriv2,
606 		    GOT_DIFF_CONFLICT_MARKER_END,
607 		    label_deriv2 ?  " " : "",
608 		    label_deriv2 ? label_deriv2 : "") < 0) {
609 			err = got_error_from_errno("dprintf");
610 			goto done;
611 		}
612 	} else if (changed_deriv)
613 		err = copy_file_to_fd(&size_deriv, f_deriv, merged_fd);
614 	else if (changed_deriv2)
615 		err = copy_file_to_fd(&size_deriv2, f_deriv2, merged_fd);
616 done:
617 	if (size_orig == 0 && path_orig && unlink(path_orig) == -1 &&
618 	    err == NULL)
619 		err = got_error_from_errno2("unlink", path_orig);
620 	if (fd_orig != -1 && close(fd_orig) == -1 && err == NULL)
621 		err = got_error_from_errno2("close", path_orig);
622 	if (fd_deriv != -1 && close(fd_deriv) == -1 && err == NULL)
623 		err = got_error_from_errno2("close", path_deriv);
624 	if (fd_deriv2 != -1 && close(fd_deriv2) == -1 && err == NULL)
625 		err = got_error_from_errno2("close", path_deriv2);
626 	free(path_orig);
627 	free(path_deriv);
628 	free(path_deriv2);
629 	free(base_path_orig);
630 	free(base_path_deriv);
631 	free(base_path_deriv2);
632 	return err;
633 }
634 
635 /*
636  * Perform a 3-way merge where the file f_orig acts as the common
637  * ancestor, the file f_deriv acts as the first derived version,
638  * and the file f_deriv2 acts as the second derived version.
639  * The merge result will be written to a new file at ondisk_path; any
640  * existing file at this path will be replaced.
641  */
642 static const struct got_error *
643 merge_file(int *local_changes_subsumed, struct got_worktree *worktree,
644     FILE *f_orig, FILE *f_deriv, FILE *f_deriv2, const char *ondisk_path,
645     const char *path, uint16_t st_mode,
646     const char *label_orig, const char *label_deriv, const char *label_deriv2,
647     enum got_diff_algorithm diff_algo, struct got_repository *repo,
648     got_worktree_checkout_cb progress_cb, void *progress_arg)
649 {
650 	const struct got_error *err = NULL;
651 	int merged_fd = -1;
652 	FILE *f_merged = NULL;
653 	char *merged_path = NULL, *base_path = NULL;
654 	int overlapcnt = 0;
655 	char *parent = NULL;
656 
657 	*local_changes_subsumed = 0;
658 
659 	err = got_path_dirname(&parent, ondisk_path);
660 	if (err)
661 		return err;
662 
663 	if (asprintf(&base_path, "%s/got-merged", parent) == -1) {
664 		err = got_error_from_errno("asprintf");
665 		goto done;
666 	}
667 
668 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path, "");
669 	if (err)
670 		goto done;
671 
672 	err = got_merge_diff3(&overlapcnt, merged_fd, f_deriv, f_orig,
673 	    f_deriv2, label_deriv, label_orig, label_deriv2, diff_algo);
674 	if (err) {
675 		if (err->code != GOT_ERR_FILE_BINARY)
676 			goto done;
677 		err = merge_binary_file(&overlapcnt, merged_fd, f_deriv,
678 		    f_orig, f_deriv2, label_deriv, label_orig, label_deriv2,
679 		    ondisk_path);
680 		if (err)
681 			goto done;
682 	}
683 
684 	err = (*progress_cb)(progress_arg,
685 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
686 	if (err)
687 		goto done;
688 
689 	if (fsync(merged_fd) != 0) {
690 		err = got_error_from_errno("fsync");
691 		goto done;
692 	}
693 
694 	f_merged = fdopen(merged_fd, "r");
695 	if (f_merged == NULL) {
696 		err = got_error_from_errno("fdopen");
697 		goto done;
698 	}
699 	merged_fd = -1;
700 
701 	/* Check if a clean merge has subsumed all local changes. */
702 	if (overlapcnt == 0) {
703 		err = check_files_equal(local_changes_subsumed, f_deriv,
704 		    f_merged);
705 		if (err)
706 			goto done;
707 	}
708 
709 	if (fchmod(fileno(f_merged), apply_umask(st_mode)) != 0) {
710 		err = got_error_from_errno2("fchmod", merged_path);
711 		goto done;
712 	}
713 
714 	if (rename(merged_path, ondisk_path) != 0) {
715 		err = got_error_from_errno3("rename", merged_path,
716 		    ondisk_path);
717 		goto done;
718 	}
719 done:
720 	if (err) {
721 		if (merged_path)
722 			unlink(merged_path);
723 	}
724 	if (merged_fd != -1 && close(merged_fd) == -1 && err == NULL)
725 		err = got_error_from_errno("close");
726 	if (f_merged && fclose(f_merged) == EOF && err == NULL)
727 		err = got_error_from_errno("fclose");
728 	free(merged_path);
729 	free(base_path);
730 	free(parent);
731 	return err;
732 }
733 
734 static const struct got_error *
735 update_symlink(const char *ondisk_path, const char *target_path,
736     size_t target_len)
737 {
738 	/* This is not atomic but matches what 'ln -sf' does. */
739 	if (unlink(ondisk_path) == -1)
740 		return got_error_from_errno2("unlink", ondisk_path);
741 	if (symlink(target_path, ondisk_path) == -1)
742 		return got_error_from_errno3("symlink", target_path,
743 		    ondisk_path);
744 	return NULL;
745 }
746 
747 /*
748  * Overwrite a symlink (or a regular file in case there was a "bad" symlink)
749  * in the work tree with a file that contains conflict markers and the
750  * conflicting target paths of the original version, a "derived version"
751  * of a symlink from an incoming change, and a local version of the symlink.
752  *
753  * The original versions's target path can be NULL if it is not available,
754  * such as if both derived versions added a new symlink at the same path.
755  *
756  * The incoming derived symlink target is NULL in case the incoming change
757  * has deleted this symlink.
758  */
759 static const struct got_error *
760 install_symlink_conflict(const char *deriv_target,
761     struct got_object_id *deriv_base_commit_id, const char *orig_target,
762     const char *label_orig, const char *local_target, const char *ondisk_path)
763 {
764 	const struct got_error *err;
765 	char *id_str = NULL, *label_deriv = NULL, *path = NULL;
766 	FILE *f = NULL;
767 
768 	err = got_object_id_str(&id_str, deriv_base_commit_id);
769 	if (err)
770 		return got_error_from_errno("asprintf");
771 
772 	if (asprintf(&label_deriv, "%s: commit %s",
773 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
774 		err = got_error_from_errno("asprintf");
775 		goto done;
776 	}
777 
778 	err = got_opentemp_named(&path, &f, "got-symlink-conflict", "");
779 	if (err)
780 		goto done;
781 
782 	if (fchmod(fileno(f), apply_umask(GOT_DEFAULT_FILE_MODE)) == -1) {
783 		err = got_error_from_errno2("fchmod", path);
784 		goto done;
785 	}
786 
787 	if (fprintf(f, "%s %s\n%s\n%s%s%s%s%s\n%s\n%s\n",
788 	    GOT_DIFF_CONFLICT_MARKER_BEGIN, label_deriv,
789 	    deriv_target ? deriv_target : "(symlink was deleted)",
790 	    orig_target ? label_orig : "",
791 	    orig_target ? "\n" : "",
792 	    orig_target ? orig_target : "",
793 	    orig_target ? "\n" : "",
794 	    GOT_DIFF_CONFLICT_MARKER_SEP,
795 	    local_target, GOT_DIFF_CONFLICT_MARKER_END) < 0) {
796 		err = got_error_from_errno2("fprintf", path);
797 		goto done;
798 	}
799 
800 	if (unlink(ondisk_path) == -1) {
801 		err = got_error_from_errno2("unlink", ondisk_path);
802 		goto done;
803 	}
804 	if (rename(path, ondisk_path) == -1) {
805 		err = got_error_from_errno3("rename", path, ondisk_path);
806 		goto done;
807 	}
808 done:
809 	if (f != NULL && fclose(f) == EOF && err == NULL)
810 		err = got_error_from_errno2("fclose", path);
811 	free(path);
812 	free(id_str);
813 	free(label_deriv);
814 	return err;
815 }
816 
817 /* forward declaration */
818 static const struct got_error *
819 merge_blob(int *, struct got_worktree *, struct got_blob_object *,
820     const char *, const char *, uint16_t, const char *,
821     struct got_blob_object *, struct got_object_id *,
822     struct got_repository *, got_worktree_checkout_cb, void *);
823 
824 /*
825  * Merge a symlink into the work tree, where blob_orig acts as the common
826  * ancestor, deriv_target is the link target of the first derived version,
827  * and the symlink on disk acts as the second derived version.
828  * Assume that contents of both blobs represent symlinks.
829  */
830 static const struct got_error *
831 merge_symlink(struct got_worktree *worktree,
832     struct got_blob_object *blob_orig, const char *ondisk_path,
833     const char *path, const char *label_orig, const char *deriv_target,
834     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
835     got_worktree_checkout_cb progress_cb, void *progress_arg)
836 {
837 	const struct got_error *err = NULL;
838 	char *ancestor_target = NULL;
839 	struct stat sb;
840 	ssize_t ondisk_len, deriv_len;
841 	char ondisk_target[PATH_MAX];
842 	int have_local_change = 0;
843 	int have_incoming_change = 0;
844 
845 	if (lstat(ondisk_path, &sb) == -1)
846 		return got_error_from_errno2("lstat", ondisk_path);
847 
848 	ondisk_len = readlink(ondisk_path, ondisk_target,
849 	    sizeof(ondisk_target));
850 	if (ondisk_len == -1) {
851 		err = got_error_from_errno2("readlink",
852 		    ondisk_path);
853 		goto done;
854 	}
855 	ondisk_target[ondisk_len] = '\0';
856 
857 	if (blob_orig) {
858 		err = got_object_blob_read_to_str(&ancestor_target, blob_orig);
859 		if (err)
860 			goto done;
861 	}
862 
863 	if (ancestor_target == NULL ||
864 	    (ondisk_len != strlen(ancestor_target) ||
865 	    memcmp(ondisk_target, ancestor_target, ondisk_len) != 0))
866 		have_local_change = 1;
867 
868 	deriv_len = strlen(deriv_target);
869 	if (ancestor_target == NULL ||
870 	    (deriv_len != strlen(ancestor_target) ||
871 	    memcmp(deriv_target, ancestor_target, deriv_len) != 0))
872 		have_incoming_change = 1;
873 
874 	if (!have_local_change && !have_incoming_change) {
875 		if (ancestor_target) {
876 			/* Both sides made the same change. */
877 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
878 			    path);
879 		} else if (deriv_len == ondisk_len &&
880 		    memcmp(ondisk_target, deriv_target, deriv_len) == 0) {
881 			/* Both sides added the same symlink. */
882 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
883 			    path);
884 		} else {
885 			/* Both sides added symlinks which don't match. */
886 			err = install_symlink_conflict(deriv_target,
887 			    deriv_base_commit_id, ancestor_target,
888 			    label_orig, ondisk_target, ondisk_path);
889 			if (err)
890 				goto done;
891 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
892 			    path);
893 		}
894 	} else if (!have_local_change && have_incoming_change) {
895 		/* Apply the incoming change. */
896 		err = update_symlink(ondisk_path, deriv_target,
897 		    strlen(deriv_target));
898 		if (err)
899 			goto done;
900 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
901 	} else if (have_local_change && have_incoming_change) {
902 		if (deriv_len == ondisk_len &&
903 		    memcmp(deriv_target, ondisk_target, deriv_len) == 0) {
904 			/* Both sides made the same change. */
905 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
906 			    path);
907 		} else {
908 			err = install_symlink_conflict(deriv_target,
909 			    deriv_base_commit_id, ancestor_target, label_orig,
910 			    ondisk_target, ondisk_path);
911 			if (err)
912 				goto done;
913 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
914 			    path);
915 		}
916 	}
917 
918 done:
919 	free(ancestor_target);
920 	return err;
921 }
922 
923 static const struct got_error *
924 dump_symlink_target_path_to_file(FILE **outfile, const char *ondisk_path)
925 {
926 	const struct got_error *err = NULL;
927 	char target_path[PATH_MAX];
928 	ssize_t target_len;
929 	size_t n;
930 	FILE *f;
931 
932 	*outfile = NULL;
933 
934 	f = got_opentemp();
935 	if (f == NULL)
936 		return got_error_from_errno("got_opentemp");
937 	target_len = readlink(ondisk_path, target_path, sizeof(target_path));
938 	if (target_len == -1) {
939 		err = got_error_from_errno2("readlink", ondisk_path);
940 		goto done;
941 	}
942 	n = fwrite(target_path, 1, target_len, f);
943 	if (n != target_len) {
944 		err = got_ferror(f, GOT_ERR_IO);
945 		goto done;
946 	}
947 	if (fflush(f) == EOF) {
948 		err = got_error_from_errno("fflush");
949 		goto done;
950 	}
951 	if (fseek(f, 0L, SEEK_SET) == -1) {
952 		err = got_ferror(f, GOT_ERR_IO);
953 		goto done;
954 	}
955 done:
956 	if (err)
957 		fclose(f);
958 	else
959 		*outfile = f;
960 	return err;
961 }
962 
963 /*
964  * Perform a 3-way merge where blob_orig acts as the common ancestor,
965  * blob_deriv acts as the first derived version, and the file on disk
966  * acts as the second derived version.
967  */
968 static const struct got_error *
969 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
970     struct got_blob_object *blob_orig, const char *ondisk_path,
971     const char *path, uint16_t st_mode, const char *label_orig,
972     struct got_blob_object *blob_deriv,
973     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
974     got_worktree_checkout_cb progress_cb, void *progress_arg)
975 {
976 	const struct got_error *err = NULL;
977 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
978 	char *blob_orig_path = NULL;
979 	char *blob_deriv_path = NULL, *base_path = NULL, *id_str = NULL;
980 	char *label_deriv = NULL, *parent = NULL;
981 
982 	*local_changes_subsumed = 0;
983 
984 	err = got_path_dirname(&parent, ondisk_path);
985 	if (err)
986 		return err;
987 
988 	if (blob_orig) {
989 		if (asprintf(&base_path, "%s/got-merge-blob-orig",
990 		    parent) == -1) {
991 			err = got_error_from_errno("asprintf");
992 			base_path = NULL;
993 			goto done;
994 		}
995 
996 		err = got_opentemp_named(&blob_orig_path, &f_orig,
997 		    base_path, "");
998 		if (err)
999 			goto done;
1000 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
1001 		    blob_orig);
1002 		if (err)
1003 			goto done;
1004 		free(base_path);
1005 	} else {
1006 		/*
1007 		 * No common ancestor exists. This is an "add vs add" conflict
1008 		 * and we simply use an empty ancestor file to make both files
1009 		 * appear in the merged result in their entirety.
1010 		 */
1011 		f_orig = got_opentemp();
1012 		if (f_orig == NULL) {
1013 			err = got_error_from_errno("got_opentemp");
1014 			goto done;
1015 		}
1016 	}
1017 
1018 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
1019 		err = got_error_from_errno("asprintf");
1020 		base_path = NULL;
1021 		goto done;
1022 	}
1023 
1024 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path, "");
1025 	if (err)
1026 		goto done;
1027 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
1028 	    blob_deriv);
1029 	if (err)
1030 		goto done;
1031 
1032 	err = got_object_id_str(&id_str, deriv_base_commit_id);
1033 	if (err)
1034 		goto done;
1035 	if (asprintf(&label_deriv, "%s: commit %s",
1036 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
1037 		err = got_error_from_errno("asprintf");
1038 		goto done;
1039 	}
1040 
1041 	/*
1042 	 * In order the run a 3-way merge with a symlink we copy the symlink's
1043 	 * target path into a temporary file and use that file with diff3.
1044 	 */
1045 	if (S_ISLNK(st_mode)) {
1046 		err = dump_symlink_target_path_to_file(&f_deriv2, ondisk_path);
1047 		if (err)
1048 			goto done;
1049 	} else {
1050 		int fd;
1051 		fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1052 		if (fd == -1) {
1053 			err = got_error_from_errno2("open", ondisk_path);
1054 			goto done;
1055 		}
1056 		f_deriv2 = fdopen(fd, "r");
1057 		if (f_deriv2 == NULL) {
1058 			err = got_error_from_errno2("fdopen", ondisk_path);
1059 			close(fd);
1060 			goto done;
1061 		}
1062 	}
1063 
1064 	err = merge_file(local_changes_subsumed, worktree, f_orig, f_deriv,
1065 	    f_deriv2, ondisk_path, path, st_mode, label_orig, label_deriv,
1066 	    NULL, GOT_DIFF_ALGORITHM_MYERS, repo, progress_cb, progress_arg);
1067 done:
1068 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
1069 		err = got_error_from_errno("fclose");
1070 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
1071 		err = got_error_from_errno("fclose");
1072 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
1073 		err = got_error_from_errno("fclose");
1074 	free(base_path);
1075 	if (blob_orig_path) {
1076 		unlink(blob_orig_path);
1077 		free(blob_orig_path);
1078 	}
1079 	if (blob_deriv_path) {
1080 		unlink(blob_deriv_path);
1081 		free(blob_deriv_path);
1082 	}
1083 	free(id_str);
1084 	free(label_deriv);
1085 	free(parent);
1086 	return err;
1087 }
1088 
1089 static const struct got_error *
1090 create_fileindex_entry(struct got_fileindex_entry **new_iep,
1091     struct got_fileindex *fileindex, struct got_object_id *base_commit_id,
1092     int wt_fd, const char *path, struct got_object_id *blob_id)
1093 {
1094 	const struct got_error *err = NULL;
1095 	struct got_fileindex_entry *new_ie;
1096 
1097 	*new_iep = NULL;
1098 
1099 	err = got_fileindex_entry_alloc(&new_ie, path);
1100 	if (err)
1101 		return err;
1102 
1103 	err = got_fileindex_entry_update(new_ie, wt_fd, path,
1104 	    blob_id->sha1, base_commit_id->sha1, 1);
1105 	if (err)
1106 		goto done;
1107 
1108 	err = got_fileindex_entry_add(fileindex, new_ie);
1109 done:
1110 	if (err)
1111 		got_fileindex_entry_free(new_ie);
1112 	else
1113 		*new_iep = new_ie;
1114 	return err;
1115 }
1116 
1117 static mode_t
1118 get_ondisk_perms(int executable, mode_t st_mode)
1119 {
1120 	mode_t xbits = S_IXUSR;
1121 
1122 	if (executable) {
1123 		/* Map read bits to execute bits. */
1124 		if (st_mode & S_IRGRP)
1125 			xbits |= S_IXGRP;
1126 		if (st_mode & S_IROTH)
1127 			xbits |= S_IXOTH;
1128 		return st_mode | xbits;
1129 	}
1130 
1131 	return st_mode;
1132 }
1133 
1134 static mode_t
1135 apply_umask(mode_t mode)
1136 {
1137 	mode_t um;
1138 
1139 	um = umask(000);
1140 	umask(um);
1141 	return mode & ~um;
1142 }
1143 
1144 /* forward declaration */
1145 static const struct got_error *
1146 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1147     const char *path, mode_t te_mode, mode_t st_mode,
1148     struct got_blob_object *blob, int restoring_missing_file,
1149     int reverting_versioned_file, int installing_bad_symlink,
1150     int path_is_unversioned, struct got_repository *repo,
1151     got_worktree_checkout_cb progress_cb, void *progress_arg);
1152 
1153 /*
1154  * This function assumes that the provided symlink target points at a
1155  * safe location in the work tree!
1156  */
1157 static const struct got_error *
1158 replace_existing_symlink(int *did_something, const char *ondisk_path,
1159     const char *target_path, size_t target_len)
1160 {
1161 	const struct got_error *err = NULL;
1162 	ssize_t elen;
1163 	char etarget[PATH_MAX];
1164 	int fd;
1165 
1166 	*did_something = 0;
1167 
1168 	/*
1169 	 * "Bad" symlinks (those pointing outside the work tree or into the
1170 	 * .got directory) are installed in the work tree as a regular file
1171 	 * which contains the bad symlink target path.
1172 	 * The new symlink target has already been checked for safety by our
1173 	 * caller. If we can successfully open a regular file then we simply
1174 	 * replace this file with a symlink below.
1175 	 */
1176 	fd = open(ondisk_path, O_RDWR | O_EXCL | O_NOFOLLOW | O_CLOEXEC);
1177 	if (fd == -1) {
1178 		if (!got_err_open_nofollow_on_symlink())
1179 			return got_error_from_errno2("open", ondisk_path);
1180 
1181 		/* We are updating an existing on-disk symlink. */
1182 		elen = readlink(ondisk_path, etarget, sizeof(etarget));
1183 		if (elen == -1)
1184 			return got_error_from_errno2("readlink", ondisk_path);
1185 
1186 		if (elen == target_len &&
1187 		    memcmp(etarget, target_path, target_len) == 0)
1188 			return NULL; /* nothing to do */
1189 	}
1190 
1191 	*did_something = 1;
1192 	err = update_symlink(ondisk_path, target_path, target_len);
1193 	if (fd != -1 && close(fd) == -1 && err == NULL)
1194 		err = got_error_from_errno2("close", ondisk_path);
1195 	return err;
1196 }
1197 
1198 static const struct got_error *
1199 is_bad_symlink_target(int *is_bad_symlink, const char *target_path,
1200     size_t target_len, const char *ondisk_path, const char *wtroot_path)
1201 {
1202 	const struct got_error *err = NULL;
1203 	char canonpath[PATH_MAX];
1204 	char *path_got = NULL;
1205 
1206 	*is_bad_symlink = 0;
1207 
1208 	if (target_len >= sizeof(canonpath)) {
1209 		*is_bad_symlink = 1;
1210 		return NULL;
1211 	}
1212 
1213 	/*
1214 	 * We do not use realpath(3) to resolve the symlink's target
1215 	 * path because we don't want to resolve symlinks recursively.
1216 	 * Instead we make the path absolute and then canonicalize it.
1217 	 * Relative symlink target lookup should begin at the directory
1218 	 * in which the blob object is being installed.
1219 	 */
1220 	if (!got_path_is_absolute(target_path)) {
1221 		char *abspath, *parent;
1222 		err = got_path_dirname(&parent, ondisk_path);
1223 		if (err)
1224 			return err;
1225 		if (asprintf(&abspath, "%s/%s",  parent, target_path) == -1) {
1226 			free(parent);
1227 			return got_error_from_errno("asprintf");
1228 		}
1229 		free(parent);
1230 		if (strlen(abspath) >= sizeof(canonpath)) {
1231 			err = got_error_path(abspath, GOT_ERR_BAD_PATH);
1232 			free(abspath);
1233 			return err;
1234 		}
1235 		err = got_canonpath(abspath, canonpath, sizeof(canonpath));
1236 		free(abspath);
1237 		if (err)
1238 			return err;
1239 	} else {
1240 		err = got_canonpath(target_path, canonpath, sizeof(canonpath));
1241 		if (err)
1242 			return err;
1243 	}
1244 
1245 	/* Only allow symlinks pointing at paths within the work tree. */
1246 	if (!got_path_is_child(canonpath, wtroot_path, strlen(wtroot_path))) {
1247 		*is_bad_symlink = 1;
1248 		return NULL;
1249 	}
1250 
1251 	/* Do not allow symlinks pointing into the .got directory. */
1252 	if (asprintf(&path_got, "%s/%s", wtroot_path,
1253 	    GOT_WORKTREE_GOT_DIR) == -1)
1254 		return got_error_from_errno("asprintf");
1255 	if (got_path_is_child(canonpath, path_got, strlen(path_got)))
1256 		*is_bad_symlink = 1;
1257 
1258 	free(path_got);
1259 	return NULL;
1260 }
1261 
1262 static const struct got_error *
1263 install_symlink(int *is_bad_symlink, struct got_worktree *worktree,
1264     const char *ondisk_path, const char *path, struct got_blob_object *blob,
1265     int restoring_missing_file, int reverting_versioned_file,
1266     int path_is_unversioned, int allow_bad_symlinks,
1267     struct got_repository *repo,
1268     got_worktree_checkout_cb progress_cb, void *progress_arg)
1269 {
1270 	const struct got_error *err = NULL;
1271 	char target_path[PATH_MAX];
1272 	size_t len, target_len = 0;
1273 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1274 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1275 
1276 	*is_bad_symlink = 0;
1277 
1278 	/*
1279 	 * Blob object content specifies the target path of the link.
1280 	 * If a symbolic link cannot be installed we instead create
1281 	 * a regular file which contains the link target path stored
1282 	 * in the blob object.
1283 	 */
1284 	do {
1285 		err = got_object_blob_read_block(&len, blob);
1286 		if (err)
1287 			return err;
1288 
1289 		if (len + target_len >= sizeof(target_path)) {
1290 			/* Path too long; install as a regular file. */
1291 			*is_bad_symlink = 1;
1292 			got_object_blob_rewind(blob);
1293 			return install_blob(worktree, ondisk_path, path,
1294 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1295 			    restoring_missing_file, reverting_versioned_file,
1296 			    1, path_is_unversioned, repo, progress_cb,
1297 			    progress_arg);
1298 		}
1299 		if (len > 0) {
1300 			/* Skip blob object header first time around. */
1301 			memcpy(target_path + target_len, buf + hdrlen,
1302 			    len - hdrlen);
1303 			target_len += len - hdrlen;
1304 			hdrlen = 0;
1305 		}
1306 	} while (len != 0);
1307 	target_path[target_len] = '\0';
1308 
1309 	err = is_bad_symlink_target(is_bad_symlink, target_path, target_len,
1310 	    ondisk_path, worktree->root_path);
1311 	if (err)
1312 		return err;
1313 
1314 	if (*is_bad_symlink && !allow_bad_symlinks) {
1315 		/* install as a regular file */
1316 		got_object_blob_rewind(blob);
1317 		err = install_blob(worktree, ondisk_path, path,
1318 		    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1319 		    restoring_missing_file, reverting_versioned_file, 1,
1320 		    path_is_unversioned, repo, progress_cb, progress_arg);
1321 		return err;
1322 	}
1323 
1324 	if (symlink(target_path, ondisk_path) == -1) {
1325 		if (errno == EEXIST) {
1326 			int symlink_replaced;
1327 			if (path_is_unversioned) {
1328 				err = (*progress_cb)(progress_arg,
1329 				    GOT_STATUS_UNVERSIONED, path);
1330 				return err;
1331 			}
1332 			err = replace_existing_symlink(&symlink_replaced,
1333 			    ondisk_path, target_path, target_len);
1334 			if (err)
1335 				return err;
1336 			if (progress_cb) {
1337 				if (symlink_replaced) {
1338 					err = (*progress_cb)(progress_arg,
1339 					    reverting_versioned_file ?
1340 					    GOT_STATUS_REVERT :
1341 					    GOT_STATUS_UPDATE, path);
1342 				} else {
1343 					err = (*progress_cb)(progress_arg,
1344 					    GOT_STATUS_EXISTS, path);
1345 				}
1346 			}
1347 			return err; /* Nothing else to do. */
1348 		}
1349 
1350 		if (errno == ENOENT) {
1351 			char *parent;
1352 			err = got_path_dirname(&parent, ondisk_path);
1353 			if (err)
1354 				return err;
1355 			err = add_dir_on_disk(worktree, parent);
1356 			free(parent);
1357 			if (err)
1358 				return err;
1359 			/*
1360 			 * Retry, and fall through to error handling
1361 			 * below if this second attempt fails.
1362 			 */
1363 			if (symlink(target_path, ondisk_path) != -1) {
1364 				err = NULL; /* success */
1365 				return err;
1366 			}
1367 		}
1368 
1369 		/* Handle errors from first or second creation attempt. */
1370 		if (errno == ENAMETOOLONG) {
1371 			/* bad target path; install as a regular file */
1372 			*is_bad_symlink = 1;
1373 			got_object_blob_rewind(blob);
1374 			err = install_blob(worktree, ondisk_path, path,
1375 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1376 			    restoring_missing_file, reverting_versioned_file, 1,
1377 			    path_is_unversioned, repo,
1378 			    progress_cb, progress_arg);
1379 		} else if (errno == ENOTDIR) {
1380 			err = got_error_path(ondisk_path,
1381 			    GOT_ERR_FILE_OBSTRUCTED);
1382 		} else {
1383 			err = got_error_from_errno3("symlink",
1384 			    target_path, ondisk_path);
1385 		}
1386 	} else if (progress_cb)
1387 		err = (*progress_cb)(progress_arg, reverting_versioned_file ?
1388 		    GOT_STATUS_REVERT : GOT_STATUS_ADD, path);
1389 	return err;
1390 }
1391 
1392 static const struct got_error *
1393 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1394     const char *path, mode_t te_mode, mode_t st_mode,
1395     struct got_blob_object *blob, int restoring_missing_file,
1396     int reverting_versioned_file, int installing_bad_symlink,
1397     int path_is_unversioned, struct got_repository *repo,
1398     got_worktree_checkout_cb progress_cb, void *progress_arg)
1399 {
1400 	const struct got_error *err = NULL;
1401 	int fd = -1;
1402 	size_t len, hdrlen;
1403 	int update = 0;
1404 	char *tmppath = NULL;
1405 	mode_t mode;
1406 
1407 	mode = get_ondisk_perms(te_mode & S_IXUSR, GOT_DEFAULT_FILE_MODE);
1408 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW |
1409 	    O_CLOEXEC, mode);
1410 	if (fd == -1) {
1411 		if (errno == ENOENT) {
1412 			char *parent;
1413 			err = got_path_dirname(&parent, path);
1414 			if (err)
1415 				return err;
1416 			err = add_dir_on_disk(worktree, parent);
1417 			free(parent);
1418 			if (err)
1419 				return err;
1420 			fd = open(ondisk_path,
1421 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW | O_CLOEXEC,
1422 			    mode);
1423 			if (fd == -1)
1424 				return got_error_from_errno2("open",
1425 				    ondisk_path);
1426 		} else if (errno == EEXIST) {
1427 			if (path_is_unversioned) {
1428 				err = (*progress_cb)(progress_arg,
1429 				    GOT_STATUS_UNVERSIONED, path);
1430 				goto done;
1431 			}
1432 			if (!(S_ISLNK(st_mode) && S_ISREG(te_mode)) &&
1433 			    !S_ISREG(st_mode) && !installing_bad_symlink) {
1434 				/* TODO file is obstructed; do something */
1435 				err = got_error_path(ondisk_path,
1436 				    GOT_ERR_FILE_OBSTRUCTED);
1437 				goto done;
1438 			} else {
1439 				err = got_opentemp_named_fd(&tmppath, &fd,
1440 				    ondisk_path, "");
1441 				if (err)
1442 					goto done;
1443 				update = 1;
1444 
1445 				if (fchmod(fd, apply_umask(mode)) == -1) {
1446 					err = got_error_from_errno2("fchmod",
1447 					    tmppath);
1448 					goto done;
1449 				}
1450 			}
1451 		} else
1452 			return got_error_from_errno2("open", ondisk_path);
1453 	}
1454 
1455 	if (progress_cb) {
1456 		if (restoring_missing_file)
1457 			err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING,
1458 			    path);
1459 		else if (reverting_versioned_file)
1460 			err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT,
1461 			    path);
1462 		else
1463 			err = (*progress_cb)(progress_arg,
1464 			    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
1465 		if (err)
1466 			goto done;
1467 	}
1468 
1469 	hdrlen = got_object_blob_get_hdrlen(blob);
1470 	do {
1471 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
1472 		err = got_object_blob_read_block(&len, blob);
1473 		if (err)
1474 			break;
1475 		if (len > 0) {
1476 			/* Skip blob object header first time around. */
1477 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
1478 			if (outlen == -1) {
1479 				err = got_error_from_errno("write");
1480 				goto done;
1481 			} else if (outlen != len - hdrlen) {
1482 				err = got_error(GOT_ERR_IO);
1483 				goto done;
1484 			}
1485 			hdrlen = 0;
1486 		}
1487 	} while (len != 0);
1488 
1489 	if (fsync(fd) != 0) {
1490 		err = got_error_from_errno("fsync");
1491 		goto done;
1492 	}
1493 
1494 	if (update) {
1495 		if (S_ISLNK(st_mode) && unlink(ondisk_path) == -1) {
1496 			err = got_error_from_errno2("unlink", ondisk_path);
1497 			goto done;
1498 		}
1499 		if (rename(tmppath, ondisk_path) != 0) {
1500 			err = got_error_from_errno3("rename", tmppath,
1501 			    ondisk_path);
1502 			goto done;
1503 		}
1504 		free(tmppath);
1505 		tmppath = NULL;
1506 	}
1507 
1508 done:
1509 	if (fd != -1 && close(fd) == -1 && err == NULL)
1510 		err = got_error_from_errno("close");
1511 	if (tmppath != NULL && unlink(tmppath) == -1 && err == NULL)
1512 		err = got_error_from_errno2("unlink", tmppath);
1513 	free(tmppath);
1514 	return err;
1515 }
1516 
1517 /*
1518  * Upgrade STATUS_MODIFY to STATUS_CONFLICT if a
1519  * conflict marker is found in newly added lines only.
1520  */
1521 static const struct got_error *
1522 get_modified_file_content_status(unsigned char *status,
1523     struct got_blob_object *blob, const char *path, struct stat *sb,
1524     FILE *ondisk_file)
1525 {
1526 	const struct got_error *err, *free_err;
1527 	const char *markers[3] = {
1528 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
1529 		GOT_DIFF_CONFLICT_MARKER_SEP,
1530 		GOT_DIFF_CONFLICT_MARKER_END
1531 	};
1532 	FILE *f1 = NULL;
1533 	struct got_diffreg_result *diffreg_result = NULL;
1534 	struct diff_result *r;
1535 	int nchunks_parsed, n, i = 0, ln = 0;
1536 	char *line = NULL;
1537 	size_t linesize = 0;
1538 	ssize_t linelen;
1539 
1540 	if (*status != GOT_STATUS_MODIFY)
1541 		return NULL;
1542 
1543 	f1 = got_opentemp();
1544 	if (f1 == NULL)
1545 		return got_error_from_errno("got_opentemp");
1546 
1547 	if (blob) {
1548 		got_object_blob_rewind(blob);
1549 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
1550 		if (err)
1551 			goto done;
1552 	}
1553 
1554 	err = got_diff_files(&diffreg_result, f1, 1, NULL, ondisk_file,
1555 	    1, NULL, 0, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
1556 	if (err)
1557 		goto done;
1558 
1559 	r = diffreg_result->result;
1560 
1561 	for (n = 0; n < r->chunks.len; n += nchunks_parsed) {
1562 		struct diff_chunk *c;
1563 		struct diff_chunk_context cc = {};
1564 		off_t pos;
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 
1572 		if (diff_chunk_type(c) != CHUNK_PLUS) {
1573 			nchunks_parsed = 1;
1574 			continue;  /* removed or unchanged lines */
1575 		}
1576 
1577 		pos = diff_chunk_get_right_start_pos(c);
1578 		if (fseek(ondisk_file, pos, SEEK_SET) == -1) {
1579 			err = got_ferror(ondisk_file, GOT_ERR_IO);
1580 			goto done;
1581 		}
1582 
1583 		diff_chunk_context_load_change(&cc, &nchunks_parsed, r, n, 0);
1584 		ln = cc.right.start;
1585 
1586 		while (ln < cc.right.end) {
1587 			linelen = getline(&line, &linesize, ondisk_file);
1588 			if (linelen == -1) {
1589 				if (feof(ondisk_file))
1590 					break;
1591 				err = got_ferror(ondisk_file, GOT_ERR_IO);
1592 				break;
1593 			}
1594 
1595 			if (line && strncmp(line, markers[i],
1596 			    strlen(markers[i])) == 0) {
1597 				if (strcmp(markers[i],
1598 				    GOT_DIFF_CONFLICT_MARKER_END) == 0) {
1599 					*status = GOT_STATUS_CONFLICT;
1600 					goto done;
1601 				} else
1602 					i++;
1603 			}
1604 			++ln;
1605 		}
1606 	}
1607 
1608 done:
1609 	free(line);
1610 	if (f1 != NULL && fclose(f1) == EOF && err == NULL)
1611 		err = got_error_from_errno("fclose");
1612 	free_err = got_diffreg_result_free(diffreg_result);
1613 	if (err == NULL)
1614 		err = free_err;
1615 
1616 	return err;
1617 }
1618 
1619 static int
1620 xbit_differs(struct got_fileindex_entry *ie, uint16_t st_mode)
1621 {
1622 	mode_t ie_mode = got_fileindex_perms_to_st(ie);
1623 	return ((ie_mode & S_IXUSR) != (st_mode & S_IXUSR));
1624 }
1625 
1626 static int
1627 stat_info_differs(struct got_fileindex_entry *ie, struct stat *sb)
1628 {
1629 	return !(ie->ctime_sec == sb->st_ctim.tv_sec &&
1630 	    ie->ctime_nsec == sb->st_ctim.tv_nsec &&
1631 	    ie->mtime_sec == sb->st_mtim.tv_sec &&
1632 	    ie->mtime_nsec == sb->st_mtim.tv_nsec &&
1633 	    ie->size == (sb->st_size & 0xffffffff) &&
1634 	    !xbit_differs(ie, sb->st_mode));
1635 }
1636 
1637 static unsigned char
1638 get_staged_status(struct got_fileindex_entry *ie)
1639 {
1640 	switch (got_fileindex_entry_stage_get(ie)) {
1641 	case GOT_FILEIDX_STAGE_ADD:
1642 		return GOT_STATUS_ADD;
1643 	case GOT_FILEIDX_STAGE_DELETE:
1644 		return GOT_STATUS_DELETE;
1645 	case GOT_FILEIDX_STAGE_MODIFY:
1646 		return GOT_STATUS_MODIFY;
1647 	default:
1648 		return GOT_STATUS_NO_CHANGE;
1649 	}
1650 }
1651 
1652 static const struct got_error *
1653 get_symlink_modification_status(unsigned char *status,
1654     struct got_fileindex_entry *ie, const char *abspath,
1655     int dirfd, const char *de_name, struct got_blob_object *blob)
1656 {
1657 	const struct got_error *err = NULL;
1658 	char target_path[PATH_MAX];
1659 	char etarget[PATH_MAX];
1660 	ssize_t elen;
1661 	size_t len, target_len = 0;
1662 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1663 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1664 
1665 	*status = GOT_STATUS_NO_CHANGE;
1666 
1667 	/* Blob object content specifies the target path of the link. */
1668 	do {
1669 		err = got_object_blob_read_block(&len, blob);
1670 		if (err)
1671 			return err;
1672 		if (len + target_len >= sizeof(target_path)) {
1673 			/*
1674 			 * Should not happen. The blob contents were OK
1675 			 * when this symlink was installed.
1676 			 */
1677 			return got_error(GOT_ERR_NO_SPACE);
1678 		}
1679 		if (len > 0) {
1680 			/* Skip blob object header first time around. */
1681 			memcpy(target_path + target_len, buf + hdrlen,
1682 			    len - hdrlen);
1683 			target_len += len - hdrlen;
1684 			hdrlen = 0;
1685 		}
1686 	} while (len != 0);
1687 	target_path[target_len] = '\0';
1688 
1689 	if (dirfd != -1) {
1690 		elen = readlinkat(dirfd, de_name, etarget, sizeof(etarget));
1691 		if (elen == -1)
1692 			return got_error_from_errno2("readlinkat", abspath);
1693 	} else {
1694 		elen = readlink(abspath, etarget, sizeof(etarget));
1695 		if (elen == -1)
1696 			return got_error_from_errno2("readlink", abspath);
1697 	}
1698 
1699 	if (elen != target_len || memcmp(etarget, target_path, target_len) != 0)
1700 		*status = GOT_STATUS_MODIFY;
1701 
1702 	return NULL;
1703 }
1704 
1705 static const struct got_error *
1706 get_file_status(unsigned char *status, struct stat *sb,
1707     struct got_fileindex_entry *ie, const char *abspath,
1708     int dirfd, const char *de_name, struct got_repository *repo)
1709 {
1710 	const struct got_error *err = NULL;
1711 	struct got_object_id id;
1712 	size_t hdrlen;
1713 	int fd = -1, fd1 = -1;
1714 	FILE *f = NULL;
1715 	uint8_t fbuf[8192];
1716 	struct got_blob_object *blob = NULL;
1717 	size_t flen, blen;
1718 	unsigned char staged_status;
1719 
1720 	staged_status = get_staged_status(ie);
1721 	*status = GOT_STATUS_NO_CHANGE;
1722 	memset(sb, 0, sizeof(*sb));
1723 
1724 	/*
1725 	 * Whenever the caller provides a directory descriptor and a
1726 	 * directory entry name for the file, use them! This prevents
1727 	 * race conditions if filesystem paths change beneath our feet.
1728 	 */
1729 	if (dirfd != -1) {
1730 		if (fstatat(dirfd, de_name, sb, AT_SYMLINK_NOFOLLOW) == -1) {
1731 			if (errno == ENOENT) {
1732 				if (got_fileindex_entry_has_file_on_disk(ie))
1733 					*status = GOT_STATUS_MISSING;
1734 				else
1735 					*status = GOT_STATUS_DELETE;
1736 				goto done;
1737 			}
1738 			err = got_error_from_errno2("fstatat", abspath);
1739 			goto done;
1740 		}
1741 	} else {
1742 		fd = open(abspath, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1743 		if (fd == -1 && errno != ENOENT &&
1744 		    !got_err_open_nofollow_on_symlink())
1745 			return got_error_from_errno2("open", abspath);
1746 		else if (fd == -1 && got_err_open_nofollow_on_symlink()) {
1747 			if (lstat(abspath, sb) == -1)
1748 				return got_error_from_errno2("lstat", abspath);
1749 		} else if (fd == -1 || fstat(fd, sb) == -1) {
1750 			if (errno == ENOENT) {
1751 				if (got_fileindex_entry_has_file_on_disk(ie))
1752 					*status = GOT_STATUS_MISSING;
1753 				else
1754 					*status = GOT_STATUS_DELETE;
1755 				goto done;
1756 			}
1757 			err = got_error_from_errno2("fstat", abspath);
1758 			goto done;
1759 		}
1760 	}
1761 
1762 	if (!S_ISREG(sb->st_mode) && !S_ISLNK(sb->st_mode)) {
1763 		*status = GOT_STATUS_OBSTRUCTED;
1764 		goto done;
1765 	}
1766 
1767 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1768 		*status = GOT_STATUS_DELETE;
1769 		goto done;
1770 	} else if (!got_fileindex_entry_has_blob(ie) &&
1771 	    staged_status != GOT_STATUS_ADD) {
1772 		*status = GOT_STATUS_ADD;
1773 		goto done;
1774 	}
1775 
1776 	if (!stat_info_differs(ie, sb))
1777 		goto done;
1778 
1779 	if (S_ISLNK(sb->st_mode) &&
1780 	    got_fileindex_entry_filetype_get(ie) != GOT_FILEIDX_MODE_SYMLINK) {
1781 		*status = GOT_STATUS_MODIFY;
1782 		goto done;
1783 	}
1784 
1785 	if (staged_status == GOT_STATUS_MODIFY ||
1786 	    staged_status == GOT_STATUS_ADD)
1787 		got_fileindex_entry_get_staged_blob_id(&id, ie);
1788 	else
1789 		got_fileindex_entry_get_blob_id(&id, ie);
1790 
1791 	fd1 = got_opentempfd();
1792 	if (fd1 == -1) {
1793 		err = got_error_from_errno("got_opentempfd");
1794 		goto done;
1795 	}
1796 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf), fd1);
1797 	if (err)
1798 		goto done;
1799 
1800 	if (S_ISLNK(sb->st_mode)) {
1801 		err = get_symlink_modification_status(status, ie,
1802 		    abspath, dirfd, de_name, blob);
1803 		goto done;
1804 	}
1805 
1806 	if (dirfd != -1) {
1807 		fd = openat(dirfd, de_name, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1808 		if (fd == -1) {
1809 			err = got_error_from_errno2("openat", abspath);
1810 			goto done;
1811 		}
1812 	}
1813 
1814 	f = fdopen(fd, "r");
1815 	if (f == NULL) {
1816 		err = got_error_from_errno2("fdopen", abspath);
1817 		goto done;
1818 	}
1819 	fd = -1;
1820 	hdrlen = got_object_blob_get_hdrlen(blob);
1821 	for (;;) {
1822 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1823 		err = got_object_blob_read_block(&blen, blob);
1824 		if (err)
1825 			goto done;
1826 		/* Skip length of blob object header first time around. */
1827 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1828 		if (flen == 0 && ferror(f)) {
1829 			err = got_error_from_errno("fread");
1830 			goto done;
1831 		}
1832 		if (blen - hdrlen == 0) {
1833 			if (flen != 0)
1834 				*status = GOT_STATUS_MODIFY;
1835 			break;
1836 		} else if (flen == 0) {
1837 			if (blen - hdrlen != 0)
1838 				*status = GOT_STATUS_MODIFY;
1839 			break;
1840 		} else if (blen - hdrlen == flen) {
1841 			/* Skip blob object header first time around. */
1842 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1843 				*status = GOT_STATUS_MODIFY;
1844 				break;
1845 			}
1846 		} else {
1847 			*status = GOT_STATUS_MODIFY;
1848 			break;
1849 		}
1850 		hdrlen = 0;
1851 	}
1852 
1853 	if (*status == GOT_STATUS_MODIFY) {
1854 		rewind(f);
1855 		err = get_modified_file_content_status(status, blob, ie->path,
1856 		    sb, f);
1857 	} else if (xbit_differs(ie, sb->st_mode))
1858 		*status = GOT_STATUS_MODE_CHANGE;
1859 done:
1860 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
1861 		err = got_error_from_errno("close");
1862 	if (blob)
1863 		got_object_blob_close(blob);
1864 	if (f != NULL && fclose(f) == EOF && err == NULL)
1865 		err = got_error_from_errno2("fclose", abspath);
1866 	if (fd != -1 && close(fd) == -1 && err == NULL)
1867 		err = got_error_from_errno2("close", abspath);
1868 	return err;
1869 }
1870 
1871 /*
1872  * Update timestamps in the file index if a file is unmodified and
1873  * we had to run a full content comparison to find out.
1874  */
1875 static const struct got_error *
1876 sync_timestamps(int wt_fd, const char *path, unsigned char status,
1877     struct got_fileindex_entry *ie, struct stat *sb)
1878 {
1879 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1880 		return got_fileindex_entry_update(ie, wt_fd, path,
1881 		    ie->blob_sha1, ie->commit_sha1, 1);
1882 
1883 	return NULL;
1884 }
1885 
1886 static const struct got_error *
1887 update_blob(struct got_worktree *worktree,
1888     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1889     struct got_tree_entry *te, const char *path,
1890     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1891     void *progress_arg)
1892 {
1893 	const struct got_error *err = NULL;
1894 	struct got_blob_object *blob = NULL;
1895 	char *ondisk_path = NULL;
1896 	unsigned char status = GOT_STATUS_NO_CHANGE;
1897 	struct stat sb;
1898 	int fd1 = -1, fd2 = -1;
1899 
1900 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1901 		return got_error_from_errno("asprintf");
1902 
1903 	if (ie) {
1904 		if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE) {
1905 			err = got_error_path(ie->path, GOT_ERR_FILE_STAGED);
1906 			goto done;
1907 		}
1908 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
1909 		    repo);
1910 		if (err)
1911 			goto done;
1912 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1913 			sb.st_mode = got_fileindex_perms_to_st(ie);
1914 	} else {
1915 		if (stat(ondisk_path, &sb) == -1) {
1916 			if (errno != ENOENT) {
1917 				err = got_error_from_errno2("stat",
1918 				    ondisk_path);
1919 				goto done;
1920 			}
1921 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
1922 			status = GOT_STATUS_UNVERSIONED;
1923 		} else {
1924 			if (S_ISREG(sb.st_mode) || S_ISLNK(sb.st_mode))
1925 				status = GOT_STATUS_UNVERSIONED;
1926 			else
1927 				status = GOT_STATUS_OBSTRUCTED;
1928 		}
1929 	}
1930 
1931 	if (status == GOT_STATUS_OBSTRUCTED) {
1932 		if (ie)
1933 			got_fileindex_entry_mark_skipped(ie);
1934 		err = (*progress_cb)(progress_arg, status, path);
1935 		goto done;
1936 	}
1937 	if (status == GOT_STATUS_CONFLICT) {
1938 		if (ie)
1939 			got_fileindex_entry_mark_skipped(ie);
1940 		err = (*progress_cb)(progress_arg, GOT_STATUS_CANNOT_UPDATE,
1941 		    path);
1942 		goto done;
1943 	}
1944 
1945 	if (ie && status != GOT_STATUS_MISSING && S_ISREG(sb.st_mode) &&
1946 	    (S_ISLNK(te->mode) ||
1947 	    (te->mode & S_IXUSR) == (sb.st_mode & S_IXUSR))) {
1948 		/*
1949 		 * This is a regular file or an installed bad symlink.
1950 		 * If the file index indicates that this file is already
1951 		 * up-to-date with respect to the repository we can skip
1952 		 * updating contents of this file.
1953 		 */
1954 		if (got_fileindex_entry_has_commit(ie) &&
1955 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1956 		    SHA1_DIGEST_LENGTH) == 0) {
1957 			/* Same commit. */
1958 			err = sync_timestamps(worktree->root_fd,
1959 			    path, status, ie, &sb);
1960 			if (err)
1961 				goto done;
1962 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1963 			    path);
1964 			goto done;
1965 		}
1966 		if (got_fileindex_entry_has_blob(ie) &&
1967 		    memcmp(ie->blob_sha1, te->id.sha1,
1968 		    SHA1_DIGEST_LENGTH) == 0) {
1969 			/* Different commit but the same blob. */
1970 			err = sync_timestamps(worktree->root_fd,
1971 			    path, status, ie, &sb);
1972 			if (err)
1973 				goto done;
1974 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1975 			    path);
1976 			goto done;
1977 		}
1978 	}
1979 
1980 	fd1 = got_opentempfd();
1981 	if (fd1 == -1) {
1982 		err = got_error_from_errno("got_opentempfd");
1983 		goto done;
1984 	}
1985 	err = got_object_open_as_blob(&blob, repo, &te->id, 8192, fd1);
1986 	if (err)
1987 		goto done;
1988 
1989 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1990 		int update_timestamps;
1991 		struct got_blob_object *blob2 = NULL;
1992 		char *label_orig = NULL;
1993 		if (got_fileindex_entry_has_blob(ie)) {
1994 			fd2 = got_opentempfd();
1995 			if (fd2 == -1) {
1996 				err = got_error_from_errno("got_opentempfd");
1997 				goto done;
1998 			}
1999 			struct got_object_id id2;
2000 			got_fileindex_entry_get_blob_id(&id2, ie);
2001 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192,
2002 			    fd2);
2003 			if (err)
2004 				goto done;
2005 		}
2006 		if (got_fileindex_entry_has_commit(ie)) {
2007 			char id_str[SHA1_DIGEST_STRING_LENGTH];
2008 			if (got_sha1_digest_to_str(ie->commit_sha1, id_str,
2009 			    sizeof(id_str)) == NULL) {
2010 				err = got_error_path(id_str,
2011 				    GOT_ERR_BAD_OBJ_ID_STR);
2012 				goto done;
2013 			}
2014 			if (asprintf(&label_orig, "%s: commit %s",
2015 			    GOT_MERGE_LABEL_BASE, id_str) == -1) {
2016 				err = got_error_from_errno("asprintf");
2017 				goto done;
2018 			}
2019 		}
2020 		if (S_ISLNK(te->mode) && S_ISLNK(sb.st_mode)) {
2021 			char *link_target;
2022 			err = got_object_blob_read_to_str(&link_target, blob);
2023 			if (err)
2024 				goto done;
2025 			err = merge_symlink(worktree, blob2, ondisk_path, path,
2026 			    label_orig, link_target, worktree->base_commit_id,
2027 			    repo, progress_cb, progress_arg);
2028 			free(link_target);
2029 		} else {
2030 			err = merge_blob(&update_timestamps, worktree, blob2,
2031 			    ondisk_path, path, sb.st_mode, label_orig, blob,
2032 			    worktree->base_commit_id, repo,
2033 			    progress_cb, progress_arg);
2034 		}
2035 		free(label_orig);
2036 		if (fd2 != -1 && close(fd2) == -1 && err == NULL) {
2037 			err = got_error_from_errno("close");
2038 			goto done;
2039 		}
2040 		if (blob2)
2041 			got_object_blob_close(blob2);
2042 		if (err)
2043 			goto done;
2044 		/*
2045 		 * Do not update timestamps of files with local changes.
2046 		 * Otherwise, a future status walk would treat them as
2047 		 * unmodified files again.
2048 		 */
2049 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
2050 		    blob->id.sha1, worktree->base_commit_id->sha1,
2051 		    update_timestamps);
2052 	} else if (status == GOT_STATUS_MODE_CHANGE) {
2053 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
2054 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
2055 	} else if (status == GOT_STATUS_DELETE) {
2056 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
2057 		if (err)
2058 			goto done;
2059 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
2060 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
2061 		if (err)
2062 			goto done;
2063 	} else {
2064 		int is_bad_symlink = 0;
2065 		if (S_ISLNK(te->mode)) {
2066 			err = install_symlink(&is_bad_symlink, worktree,
2067 			    ondisk_path, path, blob,
2068 			    status == GOT_STATUS_MISSING, 0,
2069 			    status == GOT_STATUS_UNVERSIONED, 0,
2070 			    repo, progress_cb, progress_arg);
2071 		} else {
2072 			err = install_blob(worktree, ondisk_path, path,
2073 			    te->mode, sb.st_mode, blob,
2074 			    status == GOT_STATUS_MISSING, 0, 0,
2075 			    status == GOT_STATUS_UNVERSIONED, repo,
2076 			    progress_cb, progress_arg);
2077 		}
2078 		if (err)
2079 			goto done;
2080 
2081 		if (ie) {
2082 			err = got_fileindex_entry_update(ie,
2083 			    worktree->root_fd, path, blob->id.sha1,
2084 			    worktree->base_commit_id->sha1, 1);
2085 		} else {
2086 			err = create_fileindex_entry(&ie, fileindex,
2087 			    worktree->base_commit_id, worktree->root_fd, path,
2088 			    &blob->id);
2089 		}
2090 		if (err)
2091 			goto done;
2092 
2093 		if (is_bad_symlink) {
2094 			got_fileindex_entry_filetype_set(ie,
2095 			    GOT_FILEIDX_MODE_BAD_SYMLINK);
2096 		}
2097 	}
2098 
2099 	if (fd1 != -1 && close(fd1) == -1 && err == NULL) {
2100 		err = got_error_from_errno("close");
2101 		goto done;
2102 	}
2103 	got_object_blob_close(blob);
2104 done:
2105 	free(ondisk_path);
2106 	return err;
2107 }
2108 
2109 static const struct got_error *
2110 remove_ondisk_file(const char *root_path, const char *path)
2111 {
2112 	const struct got_error *err = NULL;
2113 	char *ondisk_path = NULL, *parent = NULL;
2114 
2115 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
2116 		return got_error_from_errno("asprintf");
2117 
2118 	if (unlink(ondisk_path) == -1) {
2119 		if (errno != ENOENT)
2120 			err = got_error_from_errno2("unlink", ondisk_path);
2121 	} else {
2122 		size_t root_len = strlen(root_path);
2123 		err = got_path_dirname(&parent, ondisk_path);
2124 		if (err)
2125 			goto done;
2126 		while (got_path_cmp(parent, root_path,
2127 		    strlen(parent), root_len) != 0) {
2128 			free(ondisk_path);
2129 			ondisk_path = parent;
2130 			parent = NULL;
2131 			if (rmdir(ondisk_path) == -1) {
2132 				if (errno != ENOTEMPTY)
2133 					err = got_error_from_errno2("rmdir",
2134 					    ondisk_path);
2135 				break;
2136 			}
2137 			err = got_path_dirname(&parent, ondisk_path);
2138 			if (err)
2139 				break;
2140 		}
2141 	}
2142 done:
2143 	free(ondisk_path);
2144 	free(parent);
2145 	return err;
2146 }
2147 
2148 static const struct got_error *
2149 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
2150     struct got_fileindex_entry *ie, struct got_repository *repo,
2151     got_worktree_checkout_cb progress_cb, void *progress_arg)
2152 {
2153 	const struct got_error *err = NULL;
2154 	unsigned char status;
2155 	struct stat sb;
2156 	char *ondisk_path;
2157 
2158 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
2159 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
2160 
2161 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
2162 	    == -1)
2163 		return got_error_from_errno("asprintf");
2164 
2165 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, repo);
2166 	if (err)
2167 		goto done;
2168 
2169 	if (S_ISLNK(sb.st_mode) && status != GOT_STATUS_NO_CHANGE) {
2170 		char ondisk_target[PATH_MAX];
2171 		ssize_t ondisk_len = readlink(ondisk_path, ondisk_target,
2172 		    sizeof(ondisk_target));
2173 		if (ondisk_len == -1) {
2174 			err = got_error_from_errno2("readlink", ondisk_path);
2175 			goto done;
2176 		}
2177 		ondisk_target[ondisk_len] = '\0';
2178 		err = install_symlink_conflict(NULL, worktree->base_commit_id,
2179 		    NULL, NULL, /* XXX pass common ancestor info? */
2180 		    ondisk_target, ondisk_path);
2181 		if (err)
2182 			goto done;
2183 		err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
2184 		    ie->path);
2185 		goto done;
2186 	}
2187 
2188 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
2189 	    status == GOT_STATUS_ADD) {
2190 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
2191 		if (err)
2192 			goto done;
2193 		/*
2194 		 * Preserve the working file and change the deleted blob's
2195 		 * entry into a schedule-add entry.
2196 		 */
2197 		err = got_fileindex_entry_update(ie, worktree->root_fd,
2198 		    ie->path, NULL, NULL, 0);
2199 	} else {
2200 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
2201 		if (err)
2202 			goto done;
2203 		if (status == GOT_STATUS_NO_CHANGE) {
2204 			err = remove_ondisk_file(worktree->root_path, ie->path);
2205 			if (err)
2206 				goto done;
2207 		}
2208 		got_fileindex_entry_remove(fileindex, ie);
2209 	}
2210 done:
2211 	free(ondisk_path);
2212 	return err;
2213 }
2214 
2215 struct diff_cb_arg {
2216     struct got_fileindex *fileindex;
2217     struct got_worktree *worktree;
2218     struct got_repository *repo;
2219     got_worktree_checkout_cb progress_cb;
2220     void *progress_arg;
2221     got_cancel_cb cancel_cb;
2222     void *cancel_arg;
2223 };
2224 
2225 static const struct got_error *
2226 diff_old_new(void *arg, struct got_fileindex_entry *ie,
2227     struct got_tree_entry *te, const char *parent_path)
2228 {
2229 	struct diff_cb_arg *a = arg;
2230 
2231 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2232 		return got_error(GOT_ERR_CANCELLED);
2233 
2234 	return update_blob(a->worktree, a->fileindex, ie, te,
2235 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
2236 }
2237 
2238 static const struct got_error *
2239 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2240 {
2241 	struct diff_cb_arg *a = arg;
2242 
2243 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2244 		return got_error(GOT_ERR_CANCELLED);
2245 
2246 	return delete_blob(a->worktree, a->fileindex, ie,
2247 	    a->repo, a->progress_cb, a->progress_arg);
2248 }
2249 
2250 static const struct got_error *
2251 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
2252 {
2253 	struct diff_cb_arg *a = arg;
2254 	const struct got_error *err;
2255 	char *path;
2256 
2257 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2258 		return got_error(GOT_ERR_CANCELLED);
2259 
2260 	if (got_object_tree_entry_is_submodule(te))
2261 		return NULL;
2262 
2263 	if (asprintf(&path, "%s%s%s", parent_path,
2264 	    parent_path[0] ? "/" : "", te->name)
2265 	    == -1)
2266 		return got_error_from_errno("asprintf");
2267 
2268 	if (S_ISDIR(te->mode))
2269 		err = add_dir_on_disk(a->worktree, path);
2270 	else
2271 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
2272 		    a->repo, a->progress_cb, a->progress_arg);
2273 
2274 	free(path);
2275 	return err;
2276 }
2277 
2278 const struct got_error *
2279 got_worktree_get_uuid(char **uuidstr, struct got_worktree *worktree)
2280 {
2281 	uint32_t uuid_status;
2282 
2283 	uuid_to_string(&worktree->uuid, uuidstr, &uuid_status);
2284 	if (uuid_status != uuid_s_ok) {
2285 		*uuidstr = NULL;
2286 		return got_error_uuid(uuid_status, "uuid_to_string");
2287 	}
2288 
2289 	return NULL;
2290 }
2291 
2292 static const struct got_error *
2293 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
2294 {
2295 	const struct got_error *err = NULL;
2296 	char *uuidstr = NULL;
2297 
2298 	*refname = NULL;
2299 
2300 	err = got_worktree_get_uuid(&uuidstr, worktree);
2301 	if (err)
2302 		return err;
2303 
2304 	if (asprintf(refname, "%s-%s", prefix, uuidstr) == -1) {
2305 		err = got_error_from_errno("asprintf");
2306 		*refname = NULL;
2307 	}
2308 	free(uuidstr);
2309 	return err;
2310 }
2311 
2312 const struct got_error *
2313 got_worktree_get_logmsg_ref_name(char **refname, struct got_worktree *worktree,
2314     const char *prefix)
2315 {
2316 	return get_ref_name(refname, worktree, prefix);
2317 }
2318 
2319 const struct got_error *
2320 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
2321 {
2322 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
2323 }
2324 
2325 static const struct got_error *
2326 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
2327 {
2328 	return get_ref_name(refname, worktree,
2329 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
2330 }
2331 
2332 static const struct got_error *
2333 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
2334 {
2335 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
2336 }
2337 
2338 static const struct got_error *
2339 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
2340 {
2341 	return get_ref_name(refname, worktree,
2342 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
2343 }
2344 
2345 static const struct got_error *
2346 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
2347 {
2348 	return get_ref_name(refname, worktree,
2349 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
2350 }
2351 
2352 static const struct got_error *
2353 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
2354 {
2355 	return get_ref_name(refname, worktree,
2356 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
2357 }
2358 
2359 static const struct got_error *
2360 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
2361 {
2362 	return get_ref_name(refname, worktree,
2363 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
2364 }
2365 
2366 static const struct got_error *
2367 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
2368 {
2369 	return get_ref_name(refname, worktree,
2370 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
2371 }
2372 
2373 static const struct got_error *
2374 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
2375 {
2376 	return get_ref_name(refname, worktree,
2377 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
2378 }
2379 
2380 const struct got_error *
2381 got_worktree_get_histedit_script_path(char **path,
2382     struct got_worktree *worktree)
2383 {
2384 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
2385 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
2386 		*path = NULL;
2387 		return got_error_from_errno("asprintf");
2388 	}
2389 	return NULL;
2390 }
2391 
2392 static const struct got_error *
2393 get_merge_branch_ref_name(char **refname, struct got_worktree *worktree)
2394 {
2395 	return get_ref_name(refname, worktree,
2396 	    GOT_WORKTREE_MERGE_BRANCH_REF_PREFIX);
2397 }
2398 
2399 static const struct got_error *
2400 get_merge_commit_ref_name(char **refname, struct got_worktree *worktree)
2401 {
2402 	return get_ref_name(refname, worktree,
2403 	    GOT_WORKTREE_MERGE_COMMIT_REF_PREFIX);
2404 }
2405 
2406 /*
2407  * Prevent Git's garbage collector from deleting our base commit by
2408  * setting a reference to our base commit's ID.
2409  */
2410 static const struct got_error *
2411 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
2412 {
2413 	const struct got_error *err = NULL;
2414 	struct got_reference *ref = NULL;
2415 	char *refname;
2416 
2417 	err = got_worktree_get_base_ref_name(&refname, worktree);
2418 	if (err)
2419 		return err;
2420 
2421 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
2422 	if (err)
2423 		goto done;
2424 
2425 	err = got_ref_write(ref, repo);
2426 done:
2427 	free(refname);
2428 	if (ref)
2429 		got_ref_close(ref);
2430 	return err;
2431 }
2432 
2433 static const struct got_error *
2434 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
2435 {
2436 	const struct got_error *err = NULL;
2437 
2438 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
2439 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2440 		err = got_error_from_errno("asprintf");
2441 		*fileindex_path = NULL;
2442 	}
2443 	return err;
2444 }
2445 
2446 
2447 static const struct got_error *
2448 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
2449     struct got_worktree *worktree)
2450 {
2451 	const struct got_error *err = NULL;
2452 	FILE *index = NULL;
2453 
2454 	*fileindex_path = NULL;
2455 	*fileindex = got_fileindex_alloc();
2456 	if (*fileindex == NULL)
2457 		return got_error_from_errno("got_fileindex_alloc");
2458 
2459 	err = get_fileindex_path(fileindex_path, worktree);
2460 	if (err)
2461 		goto done;
2462 
2463 	index = fopen(*fileindex_path, "rbe");
2464 	if (index == NULL) {
2465 		if (errno != ENOENT)
2466 			err = got_error_from_errno2("fopen", *fileindex_path);
2467 	} else {
2468 		err = got_fileindex_read(*fileindex, index);
2469 		if (fclose(index) == EOF && err == NULL)
2470 			err = got_error_from_errno("fclose");
2471 	}
2472 done:
2473 	if (err) {
2474 		free(*fileindex_path);
2475 		*fileindex_path = NULL;
2476 		got_fileindex_free(*fileindex);
2477 		*fileindex = NULL;
2478 	}
2479 	return err;
2480 }
2481 
2482 struct bump_base_commit_id_arg {
2483 	struct got_object_id *base_commit_id;
2484 	const char *path;
2485 	size_t path_len;
2486 	const char *entry_name;
2487 	got_worktree_checkout_cb progress_cb;
2488 	void *progress_arg;
2489 };
2490 
2491 static const struct got_error *
2492 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
2493 {
2494 	const struct got_error *err;
2495 	struct bump_base_commit_id_arg *a = arg;
2496 
2497 	if (a->entry_name) {
2498 		if (strcmp(ie->path, a->path) != 0)
2499 			return NULL;
2500 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
2501 		return NULL;
2502 
2503 	if (got_fileindex_entry_was_skipped(ie))
2504 		return NULL;
2505 
2506 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
2507 	    SHA1_DIGEST_LENGTH) == 0)
2508 		return NULL;
2509 
2510 	if (a->progress_cb) {
2511 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
2512 		    ie->path);
2513 		if (err)
2514 			return err;
2515 	}
2516 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
2517 	return NULL;
2518 }
2519 
2520 /* Bump base commit ID of all files within an updated part of the work tree. */
2521 static const struct got_error *
2522 bump_base_commit_id_everywhere(struct got_worktree *worktree,
2523     struct got_fileindex *fileindex,
2524     got_worktree_checkout_cb progress_cb, void *progress_arg)
2525 {
2526 	struct bump_base_commit_id_arg bbc_arg;
2527 
2528 	bbc_arg.base_commit_id = worktree->base_commit_id;
2529 	bbc_arg.entry_name = NULL;
2530 	bbc_arg.path = "";
2531 	bbc_arg.path_len = 0;
2532 	bbc_arg.progress_cb = progress_cb;
2533 	bbc_arg.progress_arg = progress_arg;
2534 
2535 	return got_fileindex_for_each_entry_safe(fileindex,
2536 	    bump_base_commit_id, &bbc_arg);
2537 }
2538 
2539 static const struct got_error *
2540 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
2541 {
2542 	const struct got_error *err = NULL;
2543 	char *new_fileindex_path = NULL;
2544 	FILE *new_index = NULL;
2545 	struct timespec timeout;
2546 
2547 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2548 	    fileindex_path, "");
2549 	if (err)
2550 		goto done;
2551 
2552 	err = got_fileindex_write(fileindex, new_index);
2553 	if (err)
2554 		goto done;
2555 
2556 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2557 		err = got_error_from_errno3("rename", new_fileindex_path,
2558 		    fileindex_path);
2559 		unlink(new_fileindex_path);
2560 	}
2561 
2562 	/*
2563 	 * Sleep for a short amount of time to ensure that files modified after
2564 	 * this program exits have a different time stamp from the one which
2565 	 * was recorded in the file index.
2566 	 */
2567 	timeout.tv_sec = 0;
2568 	timeout.tv_nsec = 1;
2569 	nanosleep(&timeout,  NULL);
2570 done:
2571 	if (new_index)
2572 		fclose(new_index);
2573 	free(new_fileindex_path);
2574 	return err;
2575 }
2576 
2577 static const struct got_error *
2578 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
2579     struct got_object_id **tree_id, const char *wt_relpath,
2580     struct got_commit_object *base_commit, struct got_worktree *worktree,
2581     struct got_repository *repo)
2582 {
2583 	const struct got_error *err = NULL;
2584 	struct got_object_id *id = NULL;
2585 	char *in_repo_path = NULL;
2586 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
2587 
2588 	*entry_type = GOT_OBJ_TYPE_ANY;
2589 	*tree_relpath = NULL;
2590 	*tree_id = NULL;
2591 
2592 	if (wt_relpath[0] == '\0') {
2593 		/* Check out all files within the work tree. */
2594 		*entry_type = GOT_OBJ_TYPE_TREE;
2595 		*tree_relpath = strdup("");
2596 		if (*tree_relpath == NULL) {
2597 			err = got_error_from_errno("strdup");
2598 			goto done;
2599 		}
2600 		err = got_object_id_by_path(tree_id, repo, base_commit,
2601 		    worktree->path_prefix);
2602 		if (err)
2603 			goto done;
2604 		return NULL;
2605 	}
2606 
2607 	/* Check out a subset of files in the work tree. */
2608 
2609 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
2610 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
2611 		err = got_error_from_errno("asprintf");
2612 		goto done;
2613 	}
2614 
2615 	err = got_object_id_by_path(&id, repo, base_commit, in_repo_path);
2616 	if (err)
2617 		goto done;
2618 
2619 	free(in_repo_path);
2620 	in_repo_path = NULL;
2621 
2622 	err = got_object_get_type(entry_type, repo, id);
2623 	if (err)
2624 		goto done;
2625 
2626 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
2627 		/* Check out a single file. */
2628 		if (strchr(wt_relpath, '/')  == NULL) {
2629 			/* Check out a single file in work tree's root dir. */
2630 			in_repo_path = strdup(worktree->path_prefix);
2631 			if (in_repo_path == NULL) {
2632 				err = got_error_from_errno("strdup");
2633 				goto done;
2634 			}
2635 			*tree_relpath = strdup("");
2636 			if (*tree_relpath == NULL) {
2637 				err = got_error_from_errno("strdup");
2638 				goto done;
2639 			}
2640 		} else {
2641 			/* Check out a single file in a subdirectory. */
2642 			err = got_path_dirname(tree_relpath, wt_relpath);
2643 			if (err)
2644 				return err;
2645 			if (asprintf(&in_repo_path, "%s%s%s",
2646 			    worktree->path_prefix, is_root_wt ? "" : "/",
2647 			    *tree_relpath) == -1) {
2648 				err = got_error_from_errno("asprintf");
2649 				goto done;
2650 			}
2651 		}
2652 		err = got_object_id_by_path(tree_id, repo,
2653 		    base_commit, in_repo_path);
2654 	} else {
2655 		/* Check out all files within a subdirectory. */
2656 		*tree_id = got_object_id_dup(id);
2657 		if (*tree_id == NULL) {
2658 			err = got_error_from_errno("got_object_id_dup");
2659 			goto done;
2660 		}
2661 		*tree_relpath = strdup(wt_relpath);
2662 		if (*tree_relpath == NULL) {
2663 			err = got_error_from_errno("strdup");
2664 			goto done;
2665 		}
2666 	}
2667 done:
2668 	free(id);
2669 	free(in_repo_path);
2670 	if (err) {
2671 		*entry_type = GOT_OBJ_TYPE_ANY;
2672 		free(*tree_relpath);
2673 		*tree_relpath = NULL;
2674 		free(*tree_id);
2675 		*tree_id = NULL;
2676 	}
2677 	return err;
2678 }
2679 
2680 static const struct got_error *
2681 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2682     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
2683     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2684     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
2685 {
2686 	const struct got_error *err = NULL;
2687 	struct got_commit_object *commit = NULL;
2688 	struct got_tree_object *tree = NULL;
2689 	struct got_fileindex_diff_tree_cb diff_cb;
2690 	struct diff_cb_arg arg;
2691 
2692 	err = ref_base_commit(worktree, repo);
2693 	if (err) {
2694 		if (!(err->code == GOT_ERR_ERRNO &&
2695 		    (errno == EACCES || errno == EROFS)))
2696 			goto done;
2697 		err = (*progress_cb)(progress_arg,
2698 		    GOT_STATUS_BASE_REF_ERR, worktree->root_path);
2699 		if (err)
2700 			return err;
2701 	}
2702 
2703 	err = got_object_open_as_commit(&commit, repo,
2704 	    worktree->base_commit_id);
2705 	if (err)
2706 		goto done;
2707 
2708 	err = got_object_open_as_tree(&tree, repo, tree_id);
2709 	if (err)
2710 		goto done;
2711 
2712 	if (entry_name &&
2713 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
2714 		err = got_error_path(entry_name, GOT_ERR_NO_TREE_ENTRY);
2715 		goto done;
2716 	}
2717 
2718 	diff_cb.diff_old_new = diff_old_new;
2719 	diff_cb.diff_old = diff_old;
2720 	diff_cb.diff_new = diff_new;
2721 	arg.fileindex = fileindex;
2722 	arg.worktree = worktree;
2723 	arg.repo = repo;
2724 	arg.progress_cb = progress_cb;
2725 	arg.progress_arg = progress_arg;
2726 	arg.cancel_cb = cancel_cb;
2727 	arg.cancel_arg = cancel_arg;
2728 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
2729 	    entry_name, repo, &diff_cb, &arg);
2730 done:
2731 	if (tree)
2732 		got_object_tree_close(tree);
2733 	if (commit)
2734 		got_object_commit_close(commit);
2735 	return err;
2736 }
2737 
2738 const struct got_error *
2739 got_worktree_checkout_files(struct got_worktree *worktree,
2740     struct got_pathlist_head *paths, struct got_repository *repo,
2741     got_worktree_checkout_cb progress_cb, void *progress_arg,
2742     got_cancel_cb cancel_cb, void *cancel_arg)
2743 {
2744 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2745 	struct got_commit_object *commit = NULL;
2746 	struct got_tree_object *tree = NULL;
2747 	struct got_fileindex *fileindex = NULL;
2748 	char *fileindex_path = NULL;
2749 	struct got_pathlist_entry *pe;
2750 	struct tree_path_data {
2751 		STAILQ_ENTRY(tree_path_data) entry;
2752 		struct got_object_id *tree_id;
2753 		int entry_type;
2754 		char *relpath;
2755 		char *entry_name;
2756 	} *tpd = NULL;
2757 	STAILQ_HEAD(tree_paths, tree_path_data) tree_paths;
2758 
2759 	STAILQ_INIT(&tree_paths);
2760 
2761 	err = lock_worktree(worktree, LOCK_EX);
2762 	if (err)
2763 		return err;
2764 
2765 	err = got_object_open_as_commit(&commit, repo,
2766 	    worktree->base_commit_id);
2767 	if (err)
2768 		goto done;
2769 
2770 	/* Map all specified paths to in-repository trees. */
2771 	TAILQ_FOREACH(pe, paths, entry) {
2772 		tpd = malloc(sizeof(*tpd));
2773 		if (tpd == NULL) {
2774 			err = got_error_from_errno("malloc");
2775 			goto done;
2776 		}
2777 
2778 		err = find_tree_entry_for_checkout(&tpd->entry_type,
2779 		    &tpd->relpath, &tpd->tree_id, pe->path, commit,
2780 		    worktree, repo);
2781 		if (err) {
2782 			free(tpd);
2783 			goto done;
2784 		}
2785 
2786 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
2787 			err = got_path_basename(&tpd->entry_name, pe->path);
2788 			if (err) {
2789 				free(tpd->relpath);
2790 				free(tpd->tree_id);
2791 				free(tpd);
2792 				goto done;
2793 			}
2794 		} else
2795 			tpd->entry_name = NULL;
2796 
2797 		STAILQ_INSERT_TAIL(&tree_paths, tpd, entry);
2798 	}
2799 
2800 	/*
2801 	 * Read the file index.
2802 	 * Checking out files is supposed to be an idempotent operation.
2803 	 * If the on-disk file index is incomplete we will try to complete it.
2804 	 */
2805 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2806 	if (err)
2807 		goto done;
2808 
2809 	tpd = STAILQ_FIRST(&tree_paths);
2810 	TAILQ_FOREACH(pe, paths, entry) {
2811 		struct bump_base_commit_id_arg bbc_arg;
2812 
2813 		err = checkout_files(worktree, fileindex, tpd->relpath,
2814 		    tpd->tree_id, tpd->entry_name, repo,
2815 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
2816 		if (err)
2817 			break;
2818 
2819 		bbc_arg.base_commit_id = worktree->base_commit_id;
2820 		bbc_arg.entry_name = tpd->entry_name;
2821 		bbc_arg.path = pe->path;
2822 		bbc_arg.path_len = pe->path_len;
2823 		bbc_arg.progress_cb = progress_cb;
2824 		bbc_arg.progress_arg = progress_arg;
2825 		err = got_fileindex_for_each_entry_safe(fileindex,
2826 		    bump_base_commit_id, &bbc_arg);
2827 		if (err)
2828 			break;
2829 
2830 		tpd = STAILQ_NEXT(tpd, entry);
2831 	}
2832 	sync_err = sync_fileindex(fileindex, fileindex_path);
2833 	if (sync_err && err == NULL)
2834 		err = sync_err;
2835 done:
2836 	free(fileindex_path);
2837 	if (tree)
2838 		got_object_tree_close(tree);
2839 	if (commit)
2840 		got_object_commit_close(commit);
2841 	if (fileindex)
2842 		got_fileindex_free(fileindex);
2843 	while (!STAILQ_EMPTY(&tree_paths)) {
2844 		tpd = STAILQ_FIRST(&tree_paths);
2845 		STAILQ_REMOVE_HEAD(&tree_paths, entry);
2846 		free(tpd->relpath);
2847 		free(tpd->tree_id);
2848 		free(tpd);
2849 	}
2850 	unlockerr = lock_worktree(worktree, LOCK_SH);
2851 	if (unlockerr && err == NULL)
2852 		err = unlockerr;
2853 	return err;
2854 }
2855 
2856 struct merge_file_cb_arg {
2857     struct got_worktree *worktree;
2858     struct got_fileindex *fileindex;
2859     got_worktree_checkout_cb progress_cb;
2860     void *progress_arg;
2861     got_cancel_cb cancel_cb;
2862     void *cancel_arg;
2863     const char *label_orig;
2864     struct got_object_id *commit_id2;
2865     int allow_bad_symlinks;
2866 };
2867 
2868 static const struct got_error *
2869 merge_file_cb(void *arg, struct got_blob_object *blob1,
2870     struct got_blob_object *blob2, FILE *f1, FILE *f2,
2871     struct got_object_id *id1, struct got_object_id *id2,
2872     const char *path1, const char *path2,
2873     mode_t mode1, mode_t mode2, struct got_repository *repo)
2874 {
2875 	static const struct got_error *err = NULL;
2876 	struct merge_file_cb_arg *a = arg;
2877 	struct got_fileindex_entry *ie;
2878 	char *ondisk_path = NULL;
2879 	struct stat sb;
2880 	unsigned char status;
2881 	int local_changes_subsumed;
2882 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
2883 	char *id_str = NULL, *label_deriv2 = NULL;
2884 
2885 	if (blob1 && blob2) {
2886 		ie = got_fileindex_entry_get(a->fileindex, path2,
2887 		    strlen(path2));
2888 		if (ie == NULL)
2889 			return (*a->progress_cb)(a->progress_arg,
2890 			    GOT_STATUS_MISSING, path2);
2891 
2892 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2893 		    path2) == -1)
2894 			return got_error_from_errno("asprintf");
2895 
2896 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2897 		    repo);
2898 		if (err)
2899 			goto done;
2900 
2901 		if (status == GOT_STATUS_DELETE) {
2902 			err = (*a->progress_cb)(a->progress_arg,
2903 			    GOT_STATUS_MERGE, path2);
2904 			goto done;
2905 		}
2906 		if (status != GOT_STATUS_NO_CHANGE &&
2907 		    status != GOT_STATUS_MODIFY &&
2908 		    status != GOT_STATUS_CONFLICT &&
2909 		    status != GOT_STATUS_ADD) {
2910 			err = (*a->progress_cb)(a->progress_arg, status, path2);
2911 			goto done;
2912 		}
2913 
2914 		if (S_ISLNK(mode1) && S_ISLNK(mode2)) {
2915 			char *link_target2;
2916 			err = got_object_blob_read_to_str(&link_target2, blob2);
2917 			if (err)
2918 				goto done;
2919 			err = merge_symlink(a->worktree, blob1, ondisk_path,
2920 			    path2, a->label_orig, link_target2, a->commit_id2,
2921 			    repo, a->progress_cb, a->progress_arg);
2922 			free(link_target2);
2923 		} else {
2924 			int fd;
2925 
2926 			f_orig = got_opentemp();
2927 			if (f_orig == NULL) {
2928 				err = got_error_from_errno("got_opentemp");
2929 				goto done;
2930 			}
2931 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2932 			    f_orig, blob1);
2933 			if (err)
2934 				goto done;
2935 
2936 			f_deriv2 = got_opentemp();
2937 			if (f_deriv2 == NULL)
2938 				goto done;
2939 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2940 			    f_deriv2, blob2);
2941 			if (err)
2942 				goto done;
2943 
2944 			fd = open(ondisk_path,
2945 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
2946 			if (fd == -1) {
2947 				err = got_error_from_errno2("open",
2948 				    ondisk_path);
2949 				goto done;
2950 			}
2951 			f_deriv = fdopen(fd, "r");
2952 			if (f_deriv == NULL) {
2953 				err = got_error_from_errno2("fdopen",
2954 				    ondisk_path);
2955 				close(fd);
2956 				goto done;
2957 			}
2958 			err = got_object_id_str(&id_str, a->commit_id2);
2959 			if (err)
2960 				goto done;
2961 			if (asprintf(&label_deriv2, "%s: commit %s",
2962 			    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
2963 				err = got_error_from_errno("asprintf");
2964 				goto done;
2965 			}
2966 			err = merge_file(&local_changes_subsumed, a->worktree,
2967 			    f_orig, f_deriv, f_deriv2, ondisk_path, path2,
2968 			    mode2, a->label_orig, NULL, label_deriv2,
2969 			    GOT_DIFF_ALGORITHM_PATIENCE, repo,
2970 			    a->progress_cb, a->progress_arg);
2971 		}
2972 	} else if (blob1) {
2973 		ie = got_fileindex_entry_get(a->fileindex, path1,
2974 		    strlen(path1));
2975 		if (ie == NULL)
2976 			return (*a->progress_cb)(a->progress_arg,
2977 			    GOT_STATUS_MISSING, path1);
2978 
2979 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2980 		    path1) == -1)
2981 			return got_error_from_errno("asprintf");
2982 
2983 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2984 		    repo);
2985 		if (err)
2986 			goto done;
2987 
2988 		switch (status) {
2989 		case GOT_STATUS_NO_CHANGE:
2990 			err = (*a->progress_cb)(a->progress_arg,
2991 			    GOT_STATUS_DELETE, path1);
2992 			if (err)
2993 				goto done;
2994 			err = remove_ondisk_file(a->worktree->root_path, path1);
2995 			if (err)
2996 				goto done;
2997 			if (ie)
2998 				got_fileindex_entry_mark_deleted_from_disk(ie);
2999 			break;
3000 		case GOT_STATUS_DELETE:
3001 		case GOT_STATUS_MISSING:
3002 			err = (*a->progress_cb)(a->progress_arg,
3003 			    GOT_STATUS_DELETE, path1);
3004 			if (err)
3005 				goto done;
3006 			if (ie)
3007 				got_fileindex_entry_mark_deleted_from_disk(ie);
3008 			break;
3009 		case GOT_STATUS_ADD: {
3010 			struct got_object_id *id;
3011 			FILE *blob1_f;
3012 			off_t blob1_size;
3013 			/*
3014 			 * Delete the added file only if its content already
3015 			 * exists in the repository.
3016 			 */
3017 			err = got_object_blob_file_create(&id, &blob1_f,
3018 			    &blob1_size, path1);
3019 			if (err)
3020 				goto done;
3021 			if (got_object_id_cmp(id, id1) == 0) {
3022 				err = (*a->progress_cb)(a->progress_arg,
3023 				    GOT_STATUS_DELETE, path1);
3024 				if (err)
3025 					goto done;
3026 				err = remove_ondisk_file(a->worktree->root_path,
3027 				    path1);
3028 				if (err)
3029 					goto done;
3030 				if (ie)
3031 					got_fileindex_entry_remove(a->fileindex,
3032 					    ie);
3033 			} else {
3034 				err = (*a->progress_cb)(a->progress_arg,
3035 				    GOT_STATUS_CANNOT_DELETE, path1);
3036 			}
3037 			if (fclose(blob1_f) == EOF && err == NULL)
3038 				err = got_error_from_errno("fclose");
3039 			free(id);
3040 			if (err)
3041 				goto done;
3042 			break;
3043 		}
3044 		case GOT_STATUS_MODIFY:
3045 		case GOT_STATUS_CONFLICT:
3046 			err = (*a->progress_cb)(a->progress_arg,
3047 			    GOT_STATUS_CANNOT_DELETE, path1);
3048 			if (err)
3049 				goto done;
3050 			break;
3051 		case GOT_STATUS_OBSTRUCTED:
3052 			err = (*a->progress_cb)(a->progress_arg, status, path1);
3053 			if (err)
3054 				goto done;
3055 			break;
3056 		default:
3057 			break;
3058 		}
3059 	} else if (blob2) {
3060 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
3061 		    path2) == -1)
3062 			return got_error_from_errno("asprintf");
3063 		ie = got_fileindex_entry_get(a->fileindex, path2,
3064 		    strlen(path2));
3065 		if (ie) {
3066 			err = get_file_status(&status, &sb, ie, ondisk_path,
3067 			    -1, NULL, repo);
3068 			if (err)
3069 				goto done;
3070 			if (status != GOT_STATUS_NO_CHANGE &&
3071 			    status != GOT_STATUS_MODIFY &&
3072 			    status != GOT_STATUS_CONFLICT &&
3073 			    status != GOT_STATUS_ADD) {
3074 				err = (*a->progress_cb)(a->progress_arg,
3075 				    status, path2);
3076 				goto done;
3077 			}
3078 			if (S_ISLNK(mode2) && S_ISLNK(sb.st_mode)) {
3079 				char *link_target2;
3080 				err = got_object_blob_read_to_str(&link_target2,
3081 				    blob2);
3082 				if (err)
3083 					goto done;
3084 				err = merge_symlink(a->worktree, NULL,
3085 				    ondisk_path, path2, a->label_orig,
3086 				    link_target2, a->commit_id2, repo,
3087 				    a->progress_cb, a->progress_arg);
3088 				free(link_target2);
3089 			} else if (S_ISREG(sb.st_mode)) {
3090 				err = merge_blob(&local_changes_subsumed,
3091 				    a->worktree, NULL, ondisk_path, path2,
3092 				    sb.st_mode, a->label_orig, blob2,
3093 				    a->commit_id2, repo, a->progress_cb,
3094 				    a->progress_arg);
3095 			} else {
3096 				err = got_error_path(ondisk_path,
3097 				    GOT_ERR_FILE_OBSTRUCTED);
3098 			}
3099 			if (err)
3100 				goto done;
3101 			if (status == GOT_STATUS_DELETE) {
3102 				err = got_fileindex_entry_update(ie,
3103 				    a->worktree->root_fd, path2, blob2->id.sha1,
3104 				    a->worktree->base_commit_id->sha1, 0);
3105 				if (err)
3106 					goto done;
3107 			}
3108 		} else {
3109 			int is_bad_symlink = 0;
3110 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
3111 			if (S_ISLNK(mode2)) {
3112 				err = install_symlink(&is_bad_symlink,
3113 				    a->worktree, ondisk_path, path2, blob2, 0,
3114 				    0, 1, a->allow_bad_symlinks, repo,
3115 				    a->progress_cb, a->progress_arg);
3116 			} else {
3117 				err = install_blob(a->worktree, ondisk_path, path2,
3118 				    mode2, sb.st_mode, blob2, 0, 0, 0, 1, repo,
3119 				    a->progress_cb, a->progress_arg);
3120 			}
3121 			if (err)
3122 				goto done;
3123 			err = got_fileindex_entry_alloc(&ie, path2);
3124 			if (err)
3125 				goto done;
3126 			err = got_fileindex_entry_update(ie,
3127 			    a->worktree->root_fd, path2, NULL, NULL, 1);
3128 			if (err) {
3129 				got_fileindex_entry_free(ie);
3130 				goto done;
3131 			}
3132 			err = got_fileindex_entry_add(a->fileindex, ie);
3133 			if (err) {
3134 				got_fileindex_entry_free(ie);
3135 				goto done;
3136 			}
3137 			if (is_bad_symlink) {
3138 				got_fileindex_entry_filetype_set(ie,
3139 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
3140 			}
3141 		}
3142 	}
3143 done:
3144 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
3145 		err = got_error_from_errno("fclose");
3146 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
3147 		err = got_error_from_errno("fclose");
3148 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
3149 		err = got_error_from_errno("fclose");
3150 	free(id_str);
3151 	free(label_deriv2);
3152 	free(ondisk_path);
3153 	return err;
3154 }
3155 
3156 static const struct got_error *
3157 check_mixed_commits(void *arg, struct got_fileindex_entry *ie)
3158 {
3159 	struct got_worktree *worktree = arg;
3160 
3161 	/* Reject merges into a work tree with mixed base commits. */
3162 	if (got_fileindex_entry_has_commit(ie) &&
3163 	    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
3164 	    SHA1_DIGEST_LENGTH) != 0)
3165 		return got_error(GOT_ERR_MIXED_COMMITS);
3166 
3167 	return NULL;
3168 }
3169 
3170 struct check_merge_conflicts_arg {
3171 	struct got_worktree *worktree;
3172 	struct got_fileindex *fileindex;
3173 	struct got_repository *repo;
3174 };
3175 
3176 static const struct got_error *
3177 check_merge_conflicts(void *arg, struct got_blob_object *blob1,
3178     struct got_blob_object *blob2, FILE *f1, FILE *f2,
3179     struct got_object_id *id1, struct got_object_id *id2,
3180     const char *path1, const char *path2,
3181     mode_t mode1, mode_t mode2, struct got_repository *repo)
3182 {
3183 	const struct got_error *err = NULL;
3184 	struct check_merge_conflicts_arg *a = arg;
3185 	unsigned char status;
3186 	struct stat sb;
3187 	struct got_fileindex_entry *ie;
3188 	const char *path = path2 ? path2 : path1;
3189 	struct got_object_id *id = id2 ? id2 : id1;
3190 	char *ondisk_path;
3191 
3192 	if (id == NULL)
3193 		return NULL;
3194 
3195 	ie = got_fileindex_entry_get(a->fileindex, path, strlen(path));
3196 	if (ie == NULL)
3197 		return NULL;
3198 
3199 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
3200 	    == -1)
3201 		return got_error_from_errno("asprintf");
3202 
3203 	/* Reject merges into a work tree with conflicted files. */
3204 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
3205 	free(ondisk_path);
3206 	if (err)
3207 		return err;
3208 	if (status == GOT_STATUS_CONFLICT)
3209 		return got_error(GOT_ERR_CONFLICTS);
3210 
3211 	return NULL;
3212 }
3213 
3214 static const struct got_error *
3215 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
3216     const char *fileindex_path, struct got_object_id *commit_id1,
3217     struct got_object_id *commit_id2, struct got_repository *repo,
3218     got_worktree_checkout_cb progress_cb, void *progress_arg,
3219     got_cancel_cb cancel_cb, void *cancel_arg)
3220 {
3221 	const struct got_error *err = NULL, *sync_err;
3222 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
3223 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
3224 	struct got_commit_object *commit1 = NULL, *commit2 = NULL;
3225 	struct check_merge_conflicts_arg cmc_arg;
3226 	struct merge_file_cb_arg arg;
3227 	char *label_orig = NULL;
3228 	FILE *f1 = NULL, *f2 = NULL;
3229 	int fd1 = -1, fd2 = -1;
3230 
3231 	if (commit_id1) {
3232 		err = got_object_open_as_commit(&commit1, repo, commit_id1);
3233 		if (err)
3234 			goto done;
3235 		err = got_object_id_by_path(&tree_id1, repo, commit1,
3236 		    worktree->path_prefix);
3237 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3238 			goto done;
3239 	}
3240 	if (tree_id1) {
3241 		char *id_str;
3242 
3243 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
3244 		if (err)
3245 			goto done;
3246 
3247 		err = got_object_id_str(&id_str, commit_id1);
3248 		if (err)
3249 			goto done;
3250 
3251 		if (asprintf(&label_orig, "%s: commit %s",
3252 		    GOT_MERGE_LABEL_BASE, id_str) == -1) {
3253 			err = got_error_from_errno("asprintf");
3254 			free(id_str);
3255 			goto done;
3256 		}
3257 		free(id_str);
3258 
3259 		f1 = got_opentemp();
3260 		if (f1 == NULL) {
3261 			err = got_error_from_errno("got_opentemp");
3262 			goto done;
3263 		}
3264 	}
3265 
3266 	err = got_object_open_as_commit(&commit2, repo, commit_id2);
3267 	if (err)
3268 		goto done;
3269 
3270 	err = got_object_id_by_path(&tree_id2, repo, commit2,
3271 	    worktree->path_prefix);
3272 	if (err)
3273 		goto done;
3274 
3275 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
3276 	if (err)
3277 		goto done;
3278 
3279 	f2 = got_opentemp();
3280 	if (f2 == NULL) {
3281 		err = got_error_from_errno("got_opentemp");
3282 		goto done;
3283 	}
3284 
3285 	fd1 = got_opentempfd();
3286 	if (fd1 == -1) {
3287 		err = got_error_from_errno("got_opentempfd");
3288 		goto done;
3289 	}
3290 
3291 	fd2 = got_opentempfd();
3292 	if (fd2 == -1) {
3293 		err = got_error_from_errno("got_opentempfd");
3294 		goto done;
3295 	}
3296 
3297 	cmc_arg.worktree = worktree;
3298 	cmc_arg.fileindex = fileindex;
3299 	cmc_arg.repo = repo;
3300 	err = got_diff_tree(tree1, tree2, f1, f2, fd1, fd2, "", "", repo,
3301 	    check_merge_conflicts, &cmc_arg, 0);
3302 	if (err)
3303 		goto done;
3304 
3305 	arg.worktree = worktree;
3306 	arg.fileindex = fileindex;
3307 	arg.progress_cb = progress_cb;
3308 	arg.progress_arg = progress_arg;
3309 	arg.cancel_cb = cancel_cb;
3310 	arg.cancel_arg = cancel_arg;
3311 	arg.label_orig = label_orig;
3312 	arg.commit_id2 = commit_id2;
3313 	arg.allow_bad_symlinks = 1; /* preserve bad symlinks across merges */
3314 	err = got_diff_tree(tree1, tree2, f1, f2, fd1, fd2, "", "", repo,
3315 	    merge_file_cb, &arg, 1);
3316 	sync_err = sync_fileindex(fileindex, fileindex_path);
3317 	if (sync_err && err == NULL)
3318 		err = sync_err;
3319 done:
3320 	if (commit1)
3321 		got_object_commit_close(commit1);
3322 	if (commit2)
3323 		got_object_commit_close(commit2);
3324 	if (tree1)
3325 		got_object_tree_close(tree1);
3326 	if (tree2)
3327 		got_object_tree_close(tree2);
3328 	if (f1 && fclose(f1) == EOF && err == NULL)
3329 		err = got_error_from_errno("fclose");
3330 	if (f2 && fclose(f2) == EOF && err == NULL)
3331 		err = got_error_from_errno("fclose");
3332 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
3333 		err = got_error_from_errno("close");
3334 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
3335 		err = got_error_from_errno("close");
3336 	free(label_orig);
3337 	return err;
3338 }
3339 
3340 const struct got_error *
3341 got_worktree_merge_files(struct got_worktree *worktree,
3342     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
3343     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
3344     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
3345 {
3346 	const struct got_error *err, *unlockerr;
3347 	char *fileindex_path = NULL;
3348 	struct got_fileindex *fileindex = NULL;
3349 
3350 	err = lock_worktree(worktree, LOCK_EX);
3351 	if (err)
3352 		return err;
3353 
3354 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3355 	if (err)
3356 		goto done;
3357 
3358 	err = got_fileindex_for_each_entry_safe(fileindex, check_mixed_commits,
3359 	    worktree);
3360 	if (err)
3361 		goto done;
3362 
3363 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
3364 	    commit_id2, repo, progress_cb, progress_arg,
3365 	    cancel_cb, cancel_arg);
3366 done:
3367 	if (fileindex)
3368 		got_fileindex_free(fileindex);
3369 	free(fileindex_path);
3370 	unlockerr = lock_worktree(worktree, LOCK_SH);
3371 	if (unlockerr && err == NULL)
3372 		err = unlockerr;
3373 	return err;
3374 }
3375 
3376 struct diff_dir_cb_arg {
3377     struct got_fileindex *fileindex;
3378     struct got_worktree *worktree;
3379     const char *status_path;
3380     size_t status_path_len;
3381     struct got_repository *repo;
3382     got_worktree_status_cb status_cb;
3383     void *status_arg;
3384     got_cancel_cb cancel_cb;
3385     void *cancel_arg;
3386     /* A pathlist containing per-directory pathlists of ignore patterns. */
3387     struct got_pathlist_head *ignores;
3388     int report_unchanged;
3389     int no_ignores;
3390 };
3391 
3392 static const struct got_error *
3393 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
3394     int dirfd, const char *de_name,
3395     got_worktree_status_cb status_cb, void *status_arg,
3396     struct got_repository *repo, int report_unchanged)
3397 {
3398 	const struct got_error *err = NULL;
3399 	unsigned char status = GOT_STATUS_NO_CHANGE;
3400 	unsigned char staged_status;
3401 	struct stat sb;
3402 	struct got_object_id blob_id, commit_id, staged_blob_id;
3403 	struct got_object_id *blob_idp = NULL, *commit_idp = NULL;
3404 	struct got_object_id *staged_blob_idp = NULL;
3405 
3406 	staged_status = get_staged_status(ie);
3407 	err = get_file_status(&status, &sb, ie, abspath, dirfd, de_name, repo);
3408 	if (err)
3409 		return err;
3410 
3411 	if (status == GOT_STATUS_NO_CHANGE &&
3412 	    staged_status == GOT_STATUS_NO_CHANGE && !report_unchanged)
3413 		return NULL;
3414 
3415 	if (got_fileindex_entry_has_blob(ie))
3416 		blob_idp = got_fileindex_entry_get_blob_id(&blob_id, ie);
3417 	if (got_fileindex_entry_has_commit(ie))
3418 		commit_idp = got_fileindex_entry_get_commit_id(&commit_id, ie);
3419 	if (staged_status == GOT_STATUS_ADD ||
3420 	    staged_status == GOT_STATUS_MODIFY) {
3421 		staged_blob_idp = got_fileindex_entry_get_staged_blob_id(
3422 		    &staged_blob_id, ie);
3423 	}
3424 
3425 	return (*status_cb)(status_arg, status, staged_status,
3426 	    ie->path, blob_idp, staged_blob_idp, commit_idp, dirfd, de_name);
3427 }
3428 
3429 static const struct got_error *
3430 status_old_new(void *arg, struct got_fileindex_entry *ie,
3431     struct dirent *de, const char *parent_path, int dirfd)
3432 {
3433 	const struct got_error *err = NULL;
3434 	struct diff_dir_cb_arg *a = arg;
3435 	char *abspath;
3436 
3437 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3438 		return got_error(GOT_ERR_CANCELLED);
3439 
3440 	if (got_path_cmp(parent_path, a->status_path,
3441 	    strlen(parent_path), a->status_path_len) != 0 &&
3442 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
3443 		return NULL;
3444 
3445 	if (parent_path[0]) {
3446 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
3447 		    parent_path, de->d_name) == -1)
3448 			return got_error_from_errno("asprintf");
3449 	} else {
3450 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
3451 		    de->d_name) == -1)
3452 			return got_error_from_errno("asprintf");
3453 	}
3454 
3455 	err = report_file_status(ie, abspath, dirfd, de->d_name,
3456 	    a->status_cb, a->status_arg, a->repo, a->report_unchanged);
3457 	free(abspath);
3458 	return err;
3459 }
3460 
3461 static const struct got_error *
3462 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
3463 {
3464 	struct diff_dir_cb_arg *a = arg;
3465 	struct got_object_id blob_id, commit_id;
3466 	unsigned char status;
3467 
3468 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3469 		return got_error(GOT_ERR_CANCELLED);
3470 
3471 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
3472 		return NULL;
3473 
3474 	got_fileindex_entry_get_blob_id(&blob_id, ie);
3475 	got_fileindex_entry_get_commit_id(&commit_id, ie);
3476 	if (got_fileindex_entry_has_file_on_disk(ie))
3477 		status = GOT_STATUS_MISSING;
3478 	else
3479 		status = GOT_STATUS_DELETE;
3480 	return (*a->status_cb)(a->status_arg, status, get_staged_status(ie),
3481 	    ie->path, &blob_id, NULL, &commit_id, -1, NULL);
3482 }
3483 
3484 static void
3485 free_ignores(struct got_pathlist_head *ignores)
3486 {
3487 	struct got_pathlist_entry *pe;
3488 
3489 	TAILQ_FOREACH(pe, ignores, entry) {
3490 		struct got_pathlist_head *ignorelist = pe->data;
3491 
3492 		got_pathlist_free(ignorelist, GOT_PATHLIST_FREE_PATH);
3493 	}
3494 	got_pathlist_free(ignores, GOT_PATHLIST_FREE_PATH);
3495 }
3496 
3497 static const struct got_error *
3498 read_ignores(struct got_pathlist_head *ignores, const char *path, FILE *f)
3499 {
3500 	const struct got_error *err = NULL;
3501 	struct got_pathlist_entry *pe = NULL;
3502 	struct got_pathlist_head *ignorelist;
3503 	char *line = NULL, *pattern, *dirpath = NULL;
3504 	size_t linesize = 0;
3505 	ssize_t linelen;
3506 
3507 	ignorelist = calloc(1, sizeof(*ignorelist));
3508 	if (ignorelist == NULL)
3509 		return got_error_from_errno("calloc");
3510 	TAILQ_INIT(ignorelist);
3511 
3512 	while ((linelen = getline(&line, &linesize, f)) != -1) {
3513 		if (linelen > 0 && line[linelen - 1] == '\n')
3514 			line[linelen - 1] = '\0';
3515 
3516 		/* Git's ignores may contain comments. */
3517 		if (line[0] == '#')
3518 			continue;
3519 
3520 		/* Git's negated patterns are not (yet?) supported. */
3521 		if (line[0] == '!')
3522 			continue;
3523 
3524 		if (asprintf(&pattern, "%s%s%s", path, path[0] ? "/" : "",
3525 		    line) == -1) {
3526 			err = got_error_from_errno("asprintf");
3527 			goto done;
3528 		}
3529 		err = got_pathlist_insert(NULL, ignorelist, pattern, NULL);
3530 		if (err)
3531 			goto done;
3532 	}
3533 	if (ferror(f)) {
3534 		err = got_error_from_errno("getline");
3535 		goto done;
3536 	}
3537 
3538 	dirpath = strdup(path);
3539 	if (dirpath == NULL) {
3540 		err = got_error_from_errno("strdup");
3541 		goto done;
3542 	}
3543 	err = got_pathlist_insert(&pe, ignores, dirpath, ignorelist);
3544 done:
3545 	free(line);
3546 	if (err || pe == NULL) {
3547 		free(dirpath);
3548 		got_pathlist_free(ignorelist, GOT_PATHLIST_FREE_PATH);
3549 	}
3550 	return err;
3551 }
3552 
3553 static int
3554 match_path(const char *pattern, size_t pattern_len, const char *path,
3555     int flags)
3556 {
3557 	char buf[PATH_MAX];
3558 
3559 	/*
3560 	 * Trailing slashes signify directories.
3561 	 * Append a * to make such patterns conform to fnmatch rules.
3562 	 */
3563 	if (pattern_len > 0 && pattern[pattern_len - 1] == '/') {
3564 		if (snprintf(buf, sizeof(buf), "%s*", pattern) >= sizeof(buf))
3565 			return FNM_NOMATCH; /* XXX */
3566 
3567 		return fnmatch(buf, path, flags);
3568 	}
3569 
3570 	return fnmatch(pattern, path, flags);
3571 }
3572 
3573 static int
3574 match_ignores(struct got_pathlist_head *ignores, const char *path)
3575 {
3576 	struct got_pathlist_entry *pe;
3577 
3578 	/* Handle patterns which match in all directories. */
3579 	TAILQ_FOREACH(pe, ignores, entry) {
3580 		struct got_pathlist_head *ignorelist = pe->data;
3581 		struct got_pathlist_entry *pi;
3582 
3583 		TAILQ_FOREACH(pi, ignorelist, entry) {
3584 			const char *p;
3585 
3586 			if (pi->path_len < 3 ||
3587 			    strncmp(pi->path, "**/", 3) != 0)
3588 				continue;
3589 			p = path;
3590 			while (*p) {
3591 				if (match_path(pi->path + 3,
3592 				    pi->path_len - 3, p,
3593 				    FNM_PATHNAME | FNM_LEADING_DIR)) {
3594 					/* Retry in next directory. */
3595 					while (*p && *p != '/')
3596 						p++;
3597 					while (*p == '/')
3598 						p++;
3599 					continue;
3600 				}
3601 				return 1;
3602 			}
3603 		}
3604 	}
3605 
3606 	/*
3607 	 * The ignores pathlist contains ignore lists from children before
3608 	 * parents, so we can find the most specific ignorelist by walking
3609 	 * ignores backwards.
3610 	 */
3611 	pe = TAILQ_LAST(ignores, got_pathlist_head);
3612 	while (pe) {
3613 		if (got_path_is_child(path, pe->path, pe->path_len)) {
3614 			struct got_pathlist_head *ignorelist = pe->data;
3615 			struct got_pathlist_entry *pi;
3616 			TAILQ_FOREACH(pi, ignorelist, entry) {
3617 				int flags = FNM_LEADING_DIR;
3618 				if (strstr(pi->path, "/**/") == NULL)
3619 					flags |= FNM_PATHNAME;
3620 				if (match_path(pi->path, pi->path_len,
3621 				    path, flags))
3622 					continue;
3623 				return 1;
3624 			}
3625 		}
3626 		pe = TAILQ_PREV(pe, got_pathlist_head, entry);
3627 	}
3628 
3629 	return 0;
3630 }
3631 
3632 static const struct got_error *
3633 add_ignores(struct got_pathlist_head *ignores, const char *root_path,
3634     const char *path, int dirfd, const char *ignores_filename)
3635 {
3636 	const struct got_error *err = NULL;
3637 	char *ignorespath;
3638 	int fd = -1;
3639 	FILE *ignoresfile = NULL;
3640 
3641 	if (asprintf(&ignorespath, "%s/%s%s%s", root_path, path,
3642 	    path[0] ? "/" : "", ignores_filename) == -1)
3643 		return got_error_from_errno("asprintf");
3644 
3645 	if (dirfd != -1) {
3646 		fd = openat(dirfd, ignores_filename,
3647 		    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
3648 		if (fd == -1) {
3649 			if (errno != ENOENT && errno != EACCES)
3650 				err = got_error_from_errno2("openat",
3651 				    ignorespath);
3652 		} else {
3653 			ignoresfile = fdopen(fd, "r");
3654 			if (ignoresfile == NULL)
3655 				err = got_error_from_errno2("fdopen",
3656 				    ignorespath);
3657 			else {
3658 				fd = -1;
3659 				err = read_ignores(ignores, path, ignoresfile);
3660 			}
3661 		}
3662 	} else {
3663 		ignoresfile = fopen(ignorespath, "re");
3664 		if (ignoresfile == NULL) {
3665 			if (errno != ENOENT && errno != EACCES)
3666 				err = got_error_from_errno2("fopen",
3667 				    ignorespath);
3668 		} else
3669 			err = read_ignores(ignores, path, ignoresfile);
3670 	}
3671 
3672 	if (ignoresfile && fclose(ignoresfile) == EOF && err == NULL)
3673 		err = got_error_from_errno2("fclose", path);
3674 	if (fd != -1 && close(fd) == -1 && err == NULL)
3675 		err = got_error_from_errno2("close", path);
3676 	free(ignorespath);
3677 	return err;
3678 }
3679 
3680 static const struct got_error *
3681 status_new(int *ignore, void *arg, struct dirent *de, const char *parent_path,
3682     int dirfd)
3683 {
3684 	const struct got_error *err = NULL;
3685 	struct diff_dir_cb_arg *a = arg;
3686 	char *path = NULL;
3687 
3688 	if (ignore != NULL)
3689 		*ignore = 0;
3690 
3691 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3692 		return got_error(GOT_ERR_CANCELLED);
3693 
3694 	if (parent_path[0]) {
3695 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
3696 			return got_error_from_errno("asprintf");
3697 	} else {
3698 		path = de->d_name;
3699 	}
3700 
3701 	if (de->d_type == DT_DIR) {
3702 		if (!a->no_ignores && ignore != NULL &&
3703 		    match_ignores(a->ignores, path))
3704 			*ignore = 1;
3705 	} else if (!match_ignores(a->ignores, path) &&
3706 	    got_path_is_child(path, a->status_path, a->status_path_len))
3707 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
3708 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3709 	if (parent_path[0])
3710 		free(path);
3711 	return err;
3712 }
3713 
3714 static const struct got_error *
3715 status_traverse(void *arg, const char *path, int dirfd)
3716 {
3717 	const struct got_error *err = NULL;
3718 	struct diff_dir_cb_arg *a = arg;
3719 
3720 	if (a->no_ignores)
3721 		return NULL;
3722 
3723 	err = add_ignores(a->ignores, a->worktree->root_path,
3724 	    path, dirfd, ".cvsignore");
3725 	if (err)
3726 		return err;
3727 
3728 	err = add_ignores(a->ignores, a->worktree->root_path, path,
3729 	    dirfd, ".gitignore");
3730 
3731 	return err;
3732 }
3733 
3734 static const struct got_error *
3735 report_single_file_status(const char *path, const char *ondisk_path,
3736     struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
3737     void *status_arg, struct got_repository *repo, int report_unchanged,
3738     struct got_pathlist_head *ignores, int no_ignores)
3739 {
3740 	struct got_fileindex_entry *ie;
3741 	struct stat sb;
3742 
3743 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
3744 	if (ie)
3745 		return report_file_status(ie, ondisk_path, -1, NULL,
3746 		    status_cb, status_arg, repo, report_unchanged);
3747 
3748 	if (lstat(ondisk_path, &sb) == -1) {
3749 		if (errno != ENOENT)
3750 			return got_error_from_errno2("lstat", ondisk_path);
3751 		return (*status_cb)(status_arg, GOT_STATUS_NONEXISTENT,
3752 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3753 	}
3754 
3755 	if (!no_ignores && match_ignores(ignores, path))
3756 		return NULL;
3757 
3758 	if (S_ISREG(sb.st_mode) || S_ISLNK(sb.st_mode))
3759 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED,
3760 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3761 
3762 	return NULL;
3763 }
3764 
3765 static const struct got_error *
3766 add_ignores_from_parent_paths(struct got_pathlist_head *ignores,
3767     const char *root_path, const char *path)
3768 {
3769 	const struct got_error *err;
3770 	char *parent_path, *next_parent_path = NULL;
3771 
3772 	err = add_ignores(ignores, root_path, "", -1,
3773 	    ".cvsignore");
3774 	if (err)
3775 		return err;
3776 
3777 	err = add_ignores(ignores, root_path, "", -1,
3778 	    ".gitignore");
3779 	if (err)
3780 		return err;
3781 
3782 	err = got_path_dirname(&parent_path, path);
3783 	if (err) {
3784 		if (err->code == GOT_ERR_BAD_PATH)
3785 			return NULL; /* cannot traverse parent */
3786 		return err;
3787 	}
3788 	for (;;) {
3789 		err = add_ignores(ignores, root_path, parent_path, -1,
3790 		    ".cvsignore");
3791 		if (err)
3792 			break;
3793 		err = add_ignores(ignores, root_path, parent_path, -1,
3794 		    ".gitignore");
3795 		if (err)
3796 			break;
3797 		err = got_path_dirname(&next_parent_path, parent_path);
3798 		if (err) {
3799 			if (err->code == GOT_ERR_BAD_PATH)
3800 				err = NULL; /* traversed everything */
3801 			break;
3802 		}
3803 		if (got_path_is_root_dir(parent_path))
3804 			break;
3805 		free(parent_path);
3806 		parent_path = next_parent_path;
3807 		next_parent_path = NULL;
3808 	}
3809 
3810 	free(parent_path);
3811 	free(next_parent_path);
3812 	return err;
3813 }
3814 
3815 static const struct got_error *
3816 worktree_status(struct got_worktree *worktree, const char *path,
3817     struct got_fileindex *fileindex, struct got_repository *repo,
3818     got_worktree_status_cb status_cb, void *status_arg,
3819     got_cancel_cb cancel_cb, void *cancel_arg, int no_ignores,
3820     int report_unchanged)
3821 {
3822 	const struct got_error *err = NULL;
3823 	int fd = -1;
3824 	struct got_fileindex_diff_dir_cb fdiff_cb;
3825 	struct diff_dir_cb_arg arg;
3826 	char *ondisk_path = NULL;
3827 	struct got_pathlist_head ignores;
3828 	struct got_fileindex_entry *ie;
3829 
3830 	TAILQ_INIT(&ignores);
3831 
3832 	if (asprintf(&ondisk_path, "%s%s%s",
3833 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
3834 		return got_error_from_errno("asprintf");
3835 
3836 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
3837 	if (ie) {
3838 		err = report_single_file_status(path, ondisk_path,
3839 		    fileindex, status_cb, status_arg, repo,
3840 		    report_unchanged, &ignores, no_ignores);
3841 		goto done;
3842 	}
3843 
3844 	fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW | O_DIRECTORY | O_CLOEXEC);
3845 	if (fd == -1) {
3846 		if (errno != ENOTDIR && errno != ENOENT && errno != EACCES &&
3847 		    !got_err_open_nofollow_on_symlink())
3848 			err = got_error_from_errno2("open", ondisk_path);
3849 		else {
3850 			if (!no_ignores) {
3851 				err = add_ignores_from_parent_paths(&ignores,
3852 				    worktree->root_path, ondisk_path);
3853 				if (err)
3854 					goto done;
3855 			}
3856 			err = report_single_file_status(path, ondisk_path,
3857 			    fileindex, status_cb, status_arg, repo,
3858 			    report_unchanged, &ignores, no_ignores);
3859 		}
3860 	} else {
3861 		fdiff_cb.diff_old_new = status_old_new;
3862 		fdiff_cb.diff_old = status_old;
3863 		fdiff_cb.diff_new = status_new;
3864 		fdiff_cb.diff_traverse = status_traverse;
3865 		arg.fileindex = fileindex;
3866 		arg.worktree = worktree;
3867 		arg.status_path = path;
3868 		arg.status_path_len = strlen(path);
3869 		arg.repo = repo;
3870 		arg.status_cb = status_cb;
3871 		arg.status_arg = status_arg;
3872 		arg.cancel_cb = cancel_cb;
3873 		arg.cancel_arg = cancel_arg;
3874 		arg.report_unchanged = report_unchanged;
3875 		arg.no_ignores = no_ignores;
3876 		if (!no_ignores) {
3877 			err = add_ignores_from_parent_paths(&ignores,
3878 			    worktree->root_path, path);
3879 			if (err)
3880 				goto done;
3881 		}
3882 		arg.ignores = &ignores;
3883 		err = got_fileindex_diff_dir(fileindex, fd,
3884 		    worktree->root_path, path, repo, &fdiff_cb, &arg);
3885 	}
3886 done:
3887 	free_ignores(&ignores);
3888 	if (fd != -1 && close(fd) == -1 && err == NULL)
3889 		err = got_error_from_errno("close");
3890 	free(ondisk_path);
3891 	return err;
3892 }
3893 
3894 const struct got_error *
3895 got_worktree_status(struct got_worktree *worktree,
3896     struct got_pathlist_head *paths, struct got_repository *repo,
3897     int no_ignores, got_worktree_status_cb status_cb, void *status_arg,
3898     got_cancel_cb cancel_cb, void *cancel_arg)
3899 {
3900 	const struct got_error *err = NULL;
3901 	char *fileindex_path = NULL;
3902 	struct got_fileindex *fileindex = NULL;
3903 	struct got_pathlist_entry *pe;
3904 
3905 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3906 	if (err)
3907 		return err;
3908 
3909 	TAILQ_FOREACH(pe, paths, entry) {
3910 		err = worktree_status(worktree, pe->path, fileindex, repo,
3911 			status_cb, status_arg, cancel_cb, cancel_arg,
3912 			no_ignores, 0);
3913 		if (err)
3914 			break;
3915 	}
3916 	free(fileindex_path);
3917 	got_fileindex_free(fileindex);
3918 	return err;
3919 }
3920 
3921 const struct got_error *
3922 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
3923     const char *arg)
3924 {
3925 	const struct got_error *err = NULL;
3926 	char *resolved = NULL, *cwd = NULL, *path = NULL;
3927 	size_t len;
3928 	struct stat sb;
3929 	char *abspath = NULL;
3930 	char canonpath[PATH_MAX];
3931 
3932 	*wt_path = NULL;
3933 
3934 	cwd = getcwd(NULL, 0);
3935 	if (cwd == NULL)
3936 		return got_error_from_errno("getcwd");
3937 
3938 	if (lstat(arg, &sb) == -1) {
3939 		if (errno != ENOENT) {
3940 			err = got_error_from_errno2("lstat", arg);
3941 			goto done;
3942 		}
3943 		sb.st_mode = 0;
3944 	}
3945 	if (S_ISLNK(sb.st_mode)) {
3946 		/*
3947 		 * We cannot use realpath(3) with symlinks since we want to
3948 		 * operate on the symlink itself.
3949 		 * But we can make the path absolute, assuming it is relative
3950 		 * to the current working directory, and then canonicalize it.
3951 		 */
3952 		if (!got_path_is_absolute(arg)) {
3953 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3954 				err = got_error_from_errno("asprintf");
3955 				goto done;
3956 			}
3957 
3958 		}
3959 		err = got_canonpath(abspath ? abspath : arg, canonpath,
3960 		    sizeof(canonpath));
3961 		if (err)
3962 			goto done;
3963 		resolved = strdup(canonpath);
3964 		if (resolved == NULL) {
3965 			err = got_error_from_errno("strdup");
3966 			goto done;
3967 		}
3968 	} else {
3969 		resolved = realpath(arg, NULL);
3970 		if (resolved == NULL) {
3971 			if (errno != ENOENT) {
3972 				err = got_error_from_errno2("realpath", arg);
3973 				goto done;
3974 			}
3975 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3976 				err = got_error_from_errno("asprintf");
3977 				goto done;
3978 			}
3979 			err = got_canonpath(abspath, canonpath,
3980 			    sizeof(canonpath));
3981 			if (err)
3982 				goto done;
3983 			resolved = strdup(canonpath);
3984 			if (resolved == NULL) {
3985 				err = got_error_from_errno("strdup");
3986 				goto done;
3987 			}
3988 		}
3989 	}
3990 
3991 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
3992 	    strlen(got_worktree_get_root_path(worktree)))) {
3993 		err = got_error_path(resolved, GOT_ERR_BAD_PATH);
3994 		goto done;
3995 	}
3996 
3997 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
3998 		err = got_path_skip_common_ancestor(&path,
3999 		    got_worktree_get_root_path(worktree), resolved);
4000 		if (err)
4001 			goto done;
4002 	} else {
4003 		path = strdup("");
4004 		if (path == NULL) {
4005 			err = got_error_from_errno("strdup");
4006 			goto done;
4007 		}
4008 	}
4009 
4010 	/* XXX status walk can't deal with trailing slash! */
4011 	len = strlen(path);
4012 	while (len > 0 && path[len - 1] == '/') {
4013 		path[len - 1] = '\0';
4014 		len--;
4015 	}
4016 done:
4017 	free(abspath);
4018 	free(resolved);
4019 	free(cwd);
4020 	if (err == NULL)
4021 		*wt_path = path;
4022 	else
4023 		free(path);
4024 	return err;
4025 }
4026 
4027 struct schedule_addition_args {
4028 	struct got_worktree *worktree;
4029 	struct got_fileindex *fileindex;
4030 	got_worktree_checkout_cb progress_cb;
4031 	void *progress_arg;
4032 	struct got_repository *repo;
4033 };
4034 
4035 static const struct got_error *
4036 schedule_addition(void *arg, unsigned char status, unsigned char staged_status,
4037     const char *relpath, struct got_object_id *blob_id,
4038     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
4039     int dirfd, const char *de_name)
4040 {
4041 	struct schedule_addition_args *a = arg;
4042 	const struct got_error *err = NULL;
4043 	struct got_fileindex_entry *ie;
4044 	struct stat sb;
4045 	char *ondisk_path;
4046 
4047 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
4048 	    relpath) == -1)
4049 		return got_error_from_errno("asprintf");
4050 
4051 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4052 	if (ie) {
4053 		err = get_file_status(&status, &sb, ie, ondisk_path, dirfd,
4054 		    de_name, a->repo);
4055 		if (err)
4056 			goto done;
4057 		/* Re-adding an existing entry is a no-op. */
4058 		if (status == GOT_STATUS_ADD)
4059 			goto done;
4060 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4061 		if (err)
4062 			goto done;
4063 	}
4064 
4065 	if (status != GOT_STATUS_UNVERSIONED) {
4066 		if (status == GOT_STATUS_NONEXISTENT)
4067 			err = got_error_set_errno(ENOENT, ondisk_path);
4068 		else
4069 			err = got_error_path(ondisk_path, GOT_ERR_FILE_STATUS);
4070 		goto done;
4071 	}
4072 
4073 	err = got_fileindex_entry_alloc(&ie, relpath);
4074 	if (err)
4075 		goto done;
4076 	err = got_fileindex_entry_update(ie, a->worktree->root_fd,
4077 	    relpath, NULL, NULL, 1);
4078 	if (err) {
4079 		got_fileindex_entry_free(ie);
4080 		goto done;
4081 	}
4082 	err = got_fileindex_entry_add(a->fileindex, ie);
4083 	if (err) {
4084 		got_fileindex_entry_free(ie);
4085 		goto done;
4086 	}
4087 done:
4088 	free(ondisk_path);
4089 	if (err)
4090 		return err;
4091 	if (status == GOT_STATUS_ADD)
4092 		return NULL;
4093 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_ADD, relpath);
4094 }
4095 
4096 const struct got_error *
4097 got_worktree_schedule_add(struct got_worktree *worktree,
4098     struct got_pathlist_head *paths,
4099     got_worktree_checkout_cb progress_cb, void *progress_arg,
4100     struct got_repository *repo, int no_ignores)
4101 {
4102 	struct got_fileindex *fileindex = NULL;
4103 	char *fileindex_path = NULL;
4104 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4105 	struct got_pathlist_entry *pe;
4106 	struct schedule_addition_args saa;
4107 
4108 	err = lock_worktree(worktree, LOCK_EX);
4109 	if (err)
4110 		return err;
4111 
4112 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4113 	if (err)
4114 		goto done;
4115 
4116 	saa.worktree = worktree;
4117 	saa.fileindex = fileindex;
4118 	saa.progress_cb = progress_cb;
4119 	saa.progress_arg = progress_arg;
4120 	saa.repo = repo;
4121 
4122 	TAILQ_FOREACH(pe, paths, entry) {
4123 		err = worktree_status(worktree, pe->path, fileindex, repo,
4124 			schedule_addition, &saa, NULL, NULL, no_ignores, 0);
4125 		if (err)
4126 			break;
4127 	}
4128 	sync_err = sync_fileindex(fileindex, fileindex_path);
4129 	if (sync_err && err == NULL)
4130 		err = sync_err;
4131 done:
4132 	free(fileindex_path);
4133 	if (fileindex)
4134 		got_fileindex_free(fileindex);
4135 	unlockerr = lock_worktree(worktree, LOCK_SH);
4136 	if (unlockerr && err == NULL)
4137 		err = unlockerr;
4138 	return err;
4139 }
4140 
4141 struct schedule_deletion_args {
4142 	struct got_worktree *worktree;
4143 	struct got_fileindex *fileindex;
4144 	got_worktree_delete_cb progress_cb;
4145 	void *progress_arg;
4146 	struct got_repository *repo;
4147 	int delete_local_mods;
4148 	int keep_on_disk;
4149 	int ignore_missing_paths;
4150 	const char *status_codes;
4151 };
4152 
4153 static const struct got_error *
4154 schedule_for_deletion(void *arg, unsigned char status,
4155     unsigned char staged_status, const char *relpath,
4156     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
4157     struct got_object_id *commit_id, int dirfd, const char *de_name)
4158 {
4159 	struct schedule_deletion_args *a = arg;
4160 	const struct got_error *err = NULL;
4161 	struct got_fileindex_entry *ie = NULL;
4162 	struct stat sb;
4163 	char *ondisk_path;
4164 
4165 	if (status == GOT_STATUS_NONEXISTENT) {
4166 		if (a->ignore_missing_paths)
4167 			return NULL;
4168 		return got_error_set_errno(ENOENT, relpath);
4169 	}
4170 
4171 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4172 	if (ie == NULL)
4173 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
4174 
4175 	staged_status = get_staged_status(ie);
4176 	if (staged_status != GOT_STATUS_NO_CHANGE) {
4177 		if (staged_status == GOT_STATUS_DELETE)
4178 			return NULL;
4179 		return got_error_path(relpath, GOT_ERR_FILE_STAGED);
4180 	}
4181 
4182 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
4183 	    relpath) == -1)
4184 		return got_error_from_errno("asprintf");
4185 
4186 	err = get_file_status(&status, &sb, ie, ondisk_path, dirfd, de_name,
4187 	    a->repo);
4188 	if (err)
4189 		goto done;
4190 
4191 	if (a->status_codes) {
4192 		size_t ncodes = strlen(a->status_codes);
4193 		int i;
4194 		for (i = 0; i < ncodes ; i++) {
4195 			if (status == a->status_codes[i])
4196 				break;
4197 		}
4198 		if (i == ncodes) {
4199 			/* Do not delete files in non-matching status. */
4200 			free(ondisk_path);
4201 			return NULL;
4202 		}
4203 		if (a->status_codes[i] != GOT_STATUS_MODIFY &&
4204 		    a->status_codes[i] != GOT_STATUS_MISSING) {
4205 			static char msg[64];
4206 			snprintf(msg, sizeof(msg),
4207 			    "invalid status code '%c'", a->status_codes[i]);
4208 			err = got_error_msg(GOT_ERR_FILE_STATUS, msg);
4209 			goto done;
4210 		}
4211 	}
4212 
4213 	if (status != GOT_STATUS_NO_CHANGE) {
4214 		if (status == GOT_STATUS_DELETE)
4215 			goto done;
4216 		if (status == GOT_STATUS_MODIFY && !a->delete_local_mods) {
4217 			err = got_error_path(relpath, GOT_ERR_FILE_MODIFIED);
4218 			goto done;
4219 		}
4220 		if (status == GOT_STATUS_MISSING && !a->ignore_missing_paths) {
4221 			err = got_error_set_errno(ENOENT, relpath);
4222 			goto done;
4223 		}
4224 		if (status != GOT_STATUS_MODIFY &&
4225 		    status != GOT_STATUS_MISSING) {
4226 			err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4227 			goto done;
4228 		}
4229 	}
4230 
4231 	if (!a->keep_on_disk && status != GOT_STATUS_MISSING) {
4232 		size_t root_len;
4233 
4234 		if (dirfd != -1) {
4235 			if (unlinkat(dirfd, de_name, 0) == -1) {
4236 				err = got_error_from_errno2("unlinkat",
4237 				    ondisk_path);
4238 				goto done;
4239 			}
4240 		} else if (unlink(ondisk_path) == -1) {
4241 			err = got_error_from_errno2("unlink", ondisk_path);
4242 			goto done;
4243 		}
4244 
4245 		root_len = strlen(a->worktree->root_path);
4246 		do {
4247 			char *parent;
4248 			err = got_path_dirname(&parent, ondisk_path);
4249 			if (err)
4250 				goto done;
4251 			free(ondisk_path);
4252 			ondisk_path = parent;
4253 			if (rmdir(ondisk_path) == -1) {
4254 				if (errno != ENOTEMPTY)
4255 					err = got_error_from_errno2("rmdir",
4256 					    ondisk_path);
4257 				break;
4258 			}
4259 		} while (got_path_cmp(ondisk_path, a->worktree->root_path,
4260 		    strlen(ondisk_path), root_len) != 0);
4261 	}
4262 
4263 	got_fileindex_entry_mark_deleted_from_disk(ie);
4264 done:
4265 	free(ondisk_path);
4266 	if (err)
4267 		return err;
4268 	if (status == GOT_STATUS_DELETE)
4269 		return NULL;
4270 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_DELETE,
4271 	    staged_status, relpath);
4272 }
4273 
4274 const struct got_error *
4275 got_worktree_schedule_delete(struct got_worktree *worktree,
4276     struct got_pathlist_head *paths, int delete_local_mods,
4277     const char *status_codes,
4278     got_worktree_delete_cb progress_cb, void *progress_arg,
4279     struct got_repository *repo, int keep_on_disk, int ignore_missing_paths)
4280 {
4281 	struct got_fileindex *fileindex = NULL;
4282 	char *fileindex_path = NULL;
4283 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4284 	struct got_pathlist_entry *pe;
4285 	struct schedule_deletion_args sda;
4286 
4287 	err = lock_worktree(worktree, LOCK_EX);
4288 	if (err)
4289 		return err;
4290 
4291 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4292 	if (err)
4293 		goto done;
4294 
4295 	sda.worktree = worktree;
4296 	sda.fileindex = fileindex;
4297 	sda.progress_cb = progress_cb;
4298 	sda.progress_arg = progress_arg;
4299 	sda.repo = repo;
4300 	sda.delete_local_mods = delete_local_mods;
4301 	sda.keep_on_disk = keep_on_disk;
4302 	sda.ignore_missing_paths = ignore_missing_paths;
4303 	sda.status_codes = status_codes;
4304 
4305 	TAILQ_FOREACH(pe, paths, entry) {
4306 		err = worktree_status(worktree, pe->path, fileindex, repo,
4307 			schedule_for_deletion, &sda, NULL, NULL, 1, 1);
4308 		if (err)
4309 			break;
4310 	}
4311 	sync_err = sync_fileindex(fileindex, fileindex_path);
4312 	if (sync_err && err == NULL)
4313 		err = sync_err;
4314 done:
4315 	free(fileindex_path);
4316 	if (fileindex)
4317 		got_fileindex_free(fileindex);
4318 	unlockerr = lock_worktree(worktree, LOCK_SH);
4319 	if (unlockerr && err == NULL)
4320 		err = unlockerr;
4321 	return err;
4322 }
4323 
4324 static const struct got_error *
4325 copy_one_line(FILE *infile, FILE *outfile, FILE *rejectfile)
4326 {
4327 	const struct got_error *err = NULL;
4328 	char *line = NULL;
4329 	size_t linesize = 0, n;
4330 	ssize_t linelen;
4331 
4332 	linelen = getline(&line, &linesize, infile);
4333 	if (linelen == -1) {
4334 		if (ferror(infile)) {
4335 			err = got_error_from_errno("getline");
4336 			goto done;
4337 		}
4338 		return NULL;
4339 	}
4340 	if (outfile) {
4341 		n = fwrite(line, 1, linelen, outfile);
4342 		if (n != linelen) {
4343 			err = got_ferror(outfile, GOT_ERR_IO);
4344 			goto done;
4345 		}
4346 	}
4347 	if (rejectfile) {
4348 		n = fwrite(line, 1, linelen, rejectfile);
4349 		if (n != linelen)
4350 			err = got_ferror(rejectfile, GOT_ERR_IO);
4351 	}
4352 done:
4353 	free(line);
4354 	return err;
4355 }
4356 
4357 static const struct got_error *
4358 skip_one_line(FILE *f)
4359 {
4360 	char *line = NULL;
4361 	size_t linesize = 0;
4362 	ssize_t linelen;
4363 
4364 	linelen = getline(&line, &linesize, f);
4365 	if (linelen == -1) {
4366 		if (ferror(f))
4367 			return got_error_from_errno("getline");
4368 		return NULL;
4369 	}
4370 	free(line);
4371 	return NULL;
4372 }
4373 
4374 static const struct got_error *
4375 copy_change(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4376     int start_old, int end_old, int start_new, int end_new,
4377     FILE *outfile, FILE *rejectfile)
4378 {
4379 	const struct got_error *err;
4380 
4381 	/* Copy old file's lines leading up to patch. */
4382 	while (!feof(f1) && *line_cur1 < start_old) {
4383 		err = copy_one_line(f1, outfile, NULL);
4384 		if (err)
4385 			return err;
4386 		(*line_cur1)++;
4387 	}
4388 	/* Skip new file's lines leading up to patch. */
4389 	while (!feof(f2) && *line_cur2 < start_new) {
4390 		if (rejectfile)
4391 			err = copy_one_line(f2, NULL, rejectfile);
4392 		else
4393 			err = skip_one_line(f2);
4394 		if (err)
4395 			return err;
4396 		(*line_cur2)++;
4397 	}
4398 	/* Copy patched lines. */
4399 	while (!feof(f2) && *line_cur2 <= end_new) {
4400 		err = copy_one_line(f2, outfile, NULL);
4401 		if (err)
4402 			return err;
4403 		(*line_cur2)++;
4404 	}
4405 	/* Skip over old file's replaced lines. */
4406 	while (!feof(f1) && *line_cur1 <= end_old) {
4407 		if (rejectfile)
4408 			err = copy_one_line(f1, NULL, rejectfile);
4409 		else
4410 			err = skip_one_line(f1);
4411 		if (err)
4412 			return err;
4413 		(*line_cur1)++;
4414 	}
4415 
4416 	return NULL;
4417 }
4418 
4419 static const struct got_error *
4420 copy_remaining_content(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4421     FILE *outfile, FILE *rejectfile)
4422 {
4423 	const struct got_error *err;
4424 
4425 	if (outfile) {
4426 		/* Copy old file's lines until EOF. */
4427 		while (!feof(f1)) {
4428 			err = copy_one_line(f1, outfile, NULL);
4429 			if (err)
4430 				return err;
4431 			(*line_cur1)++;
4432 		}
4433 	}
4434 	if (rejectfile) {
4435 		/* Copy new file's lines until EOF. */
4436 		while (!feof(f2)) {
4437 			err = copy_one_line(f2, NULL, rejectfile);
4438 			if (err)
4439 				return err;
4440 			(*line_cur2)++;
4441 		}
4442 	}
4443 
4444 	return NULL;
4445 }
4446 
4447 static const struct got_error *
4448 apply_or_reject_change(int *choice, int *nchunks_used,
4449     struct diff_result *diff_result, int n,
4450     const char *relpath, FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4451     FILE *outfile, FILE *rejectfile, int changeno, int nchanges,
4452     got_worktree_patch_cb patch_cb, void *patch_arg)
4453 {
4454 	const struct got_error *err = NULL;
4455 	struct diff_chunk_context cc = {};
4456 	int start_old, end_old, start_new, end_new;
4457 	FILE *hunkfile;
4458 	struct diff_output_unidiff_state *diff_state;
4459 	struct diff_input_info diff_info;
4460 	int rc;
4461 
4462 	*choice = GOT_PATCH_CHOICE_NONE;
4463 
4464 	/* Get changed line numbers without context lines for copy_change(). */
4465 	diff_chunk_context_load_change(&cc, NULL, diff_result, n, 0);
4466 	start_old = cc.left.start;
4467 	end_old = cc.left.end;
4468 	start_new = cc.right.start;
4469 	end_new = cc.right.end;
4470 
4471 	/* Get the same change with context lines for display. */
4472 	memset(&cc, 0, sizeof(cc));
4473 	diff_chunk_context_load_change(&cc, nchunks_used, diff_result, n, 3);
4474 
4475 	memset(&diff_info, 0, sizeof(diff_info));
4476 	diff_info.left_path = relpath;
4477 	diff_info.right_path = relpath;
4478 
4479 	diff_state = diff_output_unidiff_state_alloc();
4480 	if (diff_state == NULL)
4481 		return got_error_set_errno(ENOMEM,
4482 		    "diff_output_unidiff_state_alloc");
4483 
4484 	hunkfile = got_opentemp();
4485 	if (hunkfile == NULL) {
4486 		err = got_error_from_errno("got_opentemp");
4487 		goto done;
4488 	}
4489 
4490 	rc = diff_output_unidiff_chunk(NULL, hunkfile, diff_state, &diff_info,
4491 	    diff_result, &cc);
4492 	if (rc != DIFF_RC_OK) {
4493 		err = got_error_set_errno(rc, "diff_output_unidiff_chunk");
4494 		goto done;
4495 	}
4496 
4497 	if (fseek(hunkfile, 0L, SEEK_SET) == -1) {
4498 		err = got_ferror(hunkfile, GOT_ERR_IO);
4499 		goto done;
4500 	}
4501 
4502 	err = (*patch_cb)(choice, patch_arg, GOT_STATUS_MODIFY, relpath,
4503 	    hunkfile, changeno, nchanges);
4504 	if (err)
4505 		goto done;
4506 
4507 	switch (*choice) {
4508 	case GOT_PATCH_CHOICE_YES:
4509 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4510 		    end_old, start_new, end_new, outfile, rejectfile);
4511 		break;
4512 	case GOT_PATCH_CHOICE_NO:
4513 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4514 		    end_old, start_new, end_new, rejectfile, outfile);
4515 		break;
4516 	case GOT_PATCH_CHOICE_QUIT:
4517 		break;
4518 	default:
4519 		err = got_error(GOT_ERR_PATCH_CHOICE);
4520 		break;
4521 	}
4522 done:
4523 	diff_output_unidiff_state_free(diff_state);
4524 	if (hunkfile && fclose(hunkfile) == EOF && err == NULL)
4525 		err = got_error_from_errno("fclose");
4526 	return err;
4527 }
4528 
4529 struct revert_file_args {
4530 	struct got_worktree *worktree;
4531 	struct got_fileindex *fileindex;
4532 	got_worktree_checkout_cb progress_cb;
4533 	void *progress_arg;
4534 	got_worktree_patch_cb patch_cb;
4535 	void *patch_arg;
4536 	struct got_repository *repo;
4537 	int unlink_added_files;
4538 };
4539 
4540 static const struct got_error *
4541 create_patched_content(char **path_outfile, int reverse_patch,
4542     struct got_object_id *blob_id, const char *path2,
4543     int dirfd2, const char *de_name2,
4544     const char *relpath, struct got_repository *repo,
4545     got_worktree_patch_cb patch_cb, void *patch_arg)
4546 {
4547 	const struct got_error *err, *free_err;
4548 	struct got_blob_object *blob = NULL;
4549 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL;
4550 	int fd = -1, fd2 = -1;
4551 	char link_target[PATH_MAX];
4552 	ssize_t link_len = 0;
4553 	char *path1 = NULL, *id_str = NULL;
4554 	struct stat sb2;
4555 	struct got_diffreg_result *diffreg_result = NULL;
4556 	int line_cur1 = 1, line_cur2 = 1, have_content = 0;
4557 	int i = 0, n = 0, nchunks_used = 0, nchanges = 0;
4558 
4559 	*path_outfile = NULL;
4560 
4561 	err = got_object_id_str(&id_str, blob_id);
4562 	if (err)
4563 		return err;
4564 
4565 	if (dirfd2 != -1) {
4566 		fd2 = openat(dirfd2, de_name2,
4567 		    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
4568 		if (fd2 == -1) {
4569 			if (!got_err_open_nofollow_on_symlink()) {
4570 				err = got_error_from_errno2("openat", path2);
4571 				goto done;
4572 			}
4573 			link_len = readlinkat(dirfd2, de_name2,
4574 			    link_target, sizeof(link_target));
4575 			if (link_len == -1) {
4576 				return got_error_from_errno2("readlinkat",
4577 				    path2);
4578 			}
4579 			sb2.st_mode = S_IFLNK;
4580 			sb2.st_size = link_len;
4581 		}
4582 	} else {
4583 		fd2 = open(path2, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
4584 		if (fd2 == -1) {
4585 			if (!got_err_open_nofollow_on_symlink()) {
4586 				err = got_error_from_errno2("open", path2);
4587 				goto done;
4588 			}
4589 			link_len = readlink(path2, link_target,
4590 			    sizeof(link_target));
4591 			if (link_len == -1)
4592 				return got_error_from_errno2("readlink", path2);
4593 			sb2.st_mode = S_IFLNK;
4594 			sb2.st_size = link_len;
4595 		}
4596 	}
4597 	if (fd2 != -1) {
4598 		if (fstat(fd2, &sb2) == -1) {
4599 			err = got_error_from_errno2("fstat", path2);
4600 			goto done;
4601 		}
4602 
4603 		f2 = fdopen(fd2, "r");
4604 		if (f2 == NULL) {
4605 			err = got_error_from_errno2("fdopen", path2);
4606 			goto done;
4607 		}
4608 		fd2 = -1;
4609 	} else {
4610 		size_t n;
4611 		f2 = got_opentemp();
4612 		if (f2 == NULL) {
4613 			err = got_error_from_errno2("got_opentemp", path2);
4614 			goto done;
4615 		}
4616 		n = fwrite(link_target, 1, link_len, f2);
4617 		if (n != link_len) {
4618 			err = got_ferror(f2, GOT_ERR_IO);
4619 			goto done;
4620 		}
4621 		if (fflush(f2) == EOF) {
4622 			err = got_error_from_errno("fflush");
4623 			goto done;
4624 		}
4625 		rewind(f2);
4626 	}
4627 
4628 	fd = got_opentempfd();
4629 	if (fd == -1) {
4630 		err = got_error_from_errno("got_opentempfd");
4631 		goto done;
4632 	}
4633 
4634 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192, fd);
4635 	if (err)
4636 		goto done;
4637 
4638 	err = got_opentemp_named(&path1, &f1, "got-patched-blob", "");
4639 	if (err)
4640 		goto done;
4641 
4642 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
4643 	if (err)
4644 		goto done;
4645 
4646 	err = got_diff_files(&diffreg_result, f1, 1, id_str, f2, 1, path2,
4647 	    3, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
4648 	if (err)
4649 		goto done;
4650 
4651 	err = got_opentemp_named(path_outfile, &outfile, "got-patched-content",
4652 	    "");
4653 	if (err)
4654 		goto done;
4655 
4656 	if (fseek(f1, 0L, SEEK_SET) == -1)
4657 		return got_ferror(f1, GOT_ERR_IO);
4658 	if (fseek(f2, 0L, SEEK_SET) == -1)
4659 		return got_ferror(f2, GOT_ERR_IO);
4660 
4661 	/* Count the number of actual changes in the diff result. */
4662 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4663 		struct diff_chunk_context cc = {};
4664 		diff_chunk_context_load_change(&cc, &nchunks_used,
4665 		    diffreg_result->result, n, 0);
4666 		nchanges++;
4667 	}
4668 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4669 		int choice;
4670 		err = apply_or_reject_change(&choice, &nchunks_used,
4671 		    diffreg_result->result, n, relpath, f1, f2,
4672 		    &line_cur1, &line_cur2,
4673 		    reverse_patch ? NULL : outfile,
4674 		    reverse_patch ? outfile : NULL,
4675 		    ++i, nchanges, patch_cb, patch_arg);
4676 		if (err)
4677 			goto done;
4678 		if (choice == GOT_PATCH_CHOICE_YES)
4679 			have_content = 1;
4680 		else if (choice == GOT_PATCH_CHOICE_QUIT)
4681 			break;
4682 	}
4683 	if (have_content) {
4684 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
4685 		    reverse_patch ? NULL : outfile,
4686 		    reverse_patch ? outfile : NULL);
4687 		if (err)
4688 			goto done;
4689 
4690 		if (!S_ISLNK(sb2.st_mode)) {
4691 			mode_t mode;
4692 
4693 			mode = apply_umask(sb2.st_mode);
4694 			if (fchmod(fileno(outfile), mode) == -1) {
4695 				err = got_error_from_errno2("fchmod", path2);
4696 				goto done;
4697 			}
4698 		}
4699 	}
4700 done:
4701 	free(id_str);
4702 	if (fd != -1 && close(fd) == -1 && err == NULL)
4703 		err = got_error_from_errno("close");
4704 	if (blob)
4705 		got_object_blob_close(blob);
4706 	free_err = got_diffreg_result_free(diffreg_result);
4707 	if (err == NULL)
4708 		err = free_err;
4709 	if (f1 && fclose(f1) == EOF && err == NULL)
4710 		err = got_error_from_errno2("fclose", path1);
4711 	if (f2 && fclose(f2) == EOF && err == NULL)
4712 		err = got_error_from_errno2("fclose", path2);
4713 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
4714 		err = got_error_from_errno2("close", path2);
4715 	if (outfile && fclose(outfile) == EOF && err == NULL)
4716 		err = got_error_from_errno2("fclose", *path_outfile);
4717 	if (path1 && unlink(path1) == -1 && err == NULL)
4718 		err = got_error_from_errno2("unlink", path1);
4719 	if (err || !have_content) {
4720 		if (*path_outfile && unlink(*path_outfile) == -1 && err == NULL)
4721 			err = got_error_from_errno2("unlink", *path_outfile);
4722 		free(*path_outfile);
4723 		*path_outfile = NULL;
4724 	}
4725 	free(path1);
4726 	return err;
4727 }
4728 
4729 static const struct got_error *
4730 revert_file(void *arg, unsigned char status, unsigned char staged_status,
4731     const char *relpath, struct got_object_id *blob_id,
4732     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
4733     int dirfd, const char *de_name)
4734 {
4735 	struct revert_file_args *a = arg;
4736 	const struct got_error *err = NULL;
4737 	char *parent_path = NULL;
4738 	struct got_fileindex_entry *ie;
4739 	struct got_commit_object *base_commit = NULL;
4740 	struct got_tree_object *tree = NULL;
4741 	struct got_object_id *tree_id = NULL;
4742 	const struct got_tree_entry *te = NULL;
4743 	char *tree_path = NULL, *te_name;
4744 	char *ondisk_path = NULL, *path_content = NULL;
4745 	struct got_blob_object *blob = NULL;
4746 	int fd = -1;
4747 
4748 	/* Reverting a staged deletion is a no-op. */
4749 	if (status == GOT_STATUS_DELETE &&
4750 	    staged_status != GOT_STATUS_NO_CHANGE)
4751 		return NULL;
4752 
4753 	if (status == GOT_STATUS_UNVERSIONED)
4754 		return (*a->progress_cb)(a->progress_arg,
4755 		    GOT_STATUS_UNVERSIONED, relpath);
4756 
4757 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4758 	if (ie == NULL)
4759 		return got_error_path(relpath, GOT_ERR_BAD_PATH);
4760 
4761 	/* Construct in-repository path of tree which contains this blob. */
4762 	err = got_path_dirname(&parent_path, ie->path);
4763 	if (err) {
4764 		if (err->code != GOT_ERR_BAD_PATH)
4765 			goto done;
4766 		parent_path = strdup("/");
4767 		if (parent_path == NULL) {
4768 			err = got_error_from_errno("strdup");
4769 			goto done;
4770 		}
4771 	}
4772 	if (got_path_is_root_dir(a->worktree->path_prefix)) {
4773 		tree_path = strdup(parent_path);
4774 		if (tree_path == NULL) {
4775 			err = got_error_from_errno("strdup");
4776 			goto done;
4777 		}
4778 	} else {
4779 		if (got_path_is_root_dir(parent_path)) {
4780 			tree_path = strdup(a->worktree->path_prefix);
4781 			if (tree_path == NULL) {
4782 				err = got_error_from_errno("strdup");
4783 				goto done;
4784 			}
4785 		} else {
4786 			if (asprintf(&tree_path, "%s/%s",
4787 			    a->worktree->path_prefix, parent_path) == -1) {
4788 				err = got_error_from_errno("asprintf");
4789 				goto done;
4790 			}
4791 		}
4792 	}
4793 
4794 	err = got_object_open_as_commit(&base_commit, a->repo,
4795 	    a->worktree->base_commit_id);
4796 	if (err)
4797 		goto done;
4798 
4799 	err = got_object_id_by_path(&tree_id, a->repo, base_commit, tree_path);
4800 	if (err) {
4801 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
4802 		    (status == GOT_STATUS_ADD ||
4803 		    staged_status == GOT_STATUS_ADD)))
4804 			goto done;
4805 	} else {
4806 		err = got_object_open_as_tree(&tree, a->repo, tree_id);
4807 		if (err)
4808 			goto done;
4809 
4810 		err = got_path_basename(&te_name, ie->path);
4811 		if (err)
4812 			goto done;
4813 
4814 		te = got_object_tree_find_entry(tree, te_name);
4815 		free(te_name);
4816 		if (te == NULL && status != GOT_STATUS_ADD &&
4817 		    staged_status != GOT_STATUS_ADD) {
4818 			err = got_error_path(ie->path, GOT_ERR_NO_TREE_ENTRY);
4819 			goto done;
4820 		}
4821 	}
4822 
4823 	switch (status) {
4824 	case GOT_STATUS_ADD:
4825 		if (a->patch_cb) {
4826 			int choice = GOT_PATCH_CHOICE_NONE;
4827 			err = (*a->patch_cb)(&choice, a->patch_arg,
4828 			    status, ie->path, NULL, 1, 1);
4829 			if (err)
4830 				goto done;
4831 			if (choice != GOT_PATCH_CHOICE_YES)
4832 				break;
4833 		}
4834 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_REVERT,
4835 		    ie->path);
4836 		if (err)
4837 			goto done;
4838 		got_fileindex_entry_remove(a->fileindex, ie);
4839 		if (a->unlink_added_files) {
4840 			if (asprintf(&ondisk_path, "%s/%s",
4841 			    got_worktree_get_root_path(a->worktree),
4842 			    relpath) == -1) {
4843 				err = got_error_from_errno("asprintf");
4844 				goto done;
4845 			}
4846 			if (unlink(ondisk_path) == -1) {
4847 				err = got_error_from_errno2("unlink",
4848 				    ondisk_path);
4849 				break;
4850 			}
4851 		}
4852 		break;
4853 	case GOT_STATUS_DELETE:
4854 		if (a->patch_cb) {
4855 			int choice = GOT_PATCH_CHOICE_NONE;
4856 			err = (*a->patch_cb)(&choice, a->patch_arg,
4857 			    status, ie->path, NULL, 1, 1);
4858 			if (err)
4859 				goto done;
4860 			if (choice != GOT_PATCH_CHOICE_YES)
4861 				break;
4862 		}
4863 		/* fall through */
4864 	case GOT_STATUS_MODIFY:
4865 	case GOT_STATUS_MODE_CHANGE:
4866 	case GOT_STATUS_CONFLICT:
4867 	case GOT_STATUS_MISSING: {
4868 		struct got_object_id id;
4869 		if (staged_status == GOT_STATUS_ADD ||
4870 		    staged_status == GOT_STATUS_MODIFY)
4871 			got_fileindex_entry_get_staged_blob_id(&id, ie);
4872 		else
4873 			got_fileindex_entry_get_blob_id(&id, ie);
4874 		fd = got_opentempfd();
4875 		if (fd == -1) {
4876 			err = got_error_from_errno("got_opentempfd");
4877 			goto done;
4878 		}
4879 
4880 		err = got_object_open_as_blob(&blob, a->repo, &id, 8192, fd);
4881 		if (err)
4882 			goto done;
4883 
4884 		if (asprintf(&ondisk_path, "%s/%s",
4885 		    got_worktree_get_root_path(a->worktree), relpath) == -1) {
4886 			err = got_error_from_errno("asprintf");
4887 			goto done;
4888 		}
4889 
4890 		if (a->patch_cb && (status == GOT_STATUS_MODIFY ||
4891 		    status == GOT_STATUS_CONFLICT)) {
4892 			int is_bad_symlink = 0;
4893 			err = create_patched_content(&path_content, 1, &id,
4894 			    ondisk_path, dirfd, de_name, ie->path, a->repo,
4895 			    a->patch_cb, a->patch_arg);
4896 			if (err || path_content == NULL)
4897 				break;
4898 			if (te && S_ISLNK(te->mode)) {
4899 				if (unlink(path_content) == -1) {
4900 					err = got_error_from_errno2("unlink",
4901 					    path_content);
4902 					break;
4903 				}
4904 				err = install_symlink(&is_bad_symlink,
4905 				    a->worktree, ondisk_path, ie->path,
4906 				    blob, 0, 1, 0, 0, a->repo,
4907 				    a->progress_cb, a->progress_arg);
4908 			} else {
4909 				if (rename(path_content, ondisk_path) == -1) {
4910 					err = got_error_from_errno3("rename",
4911 					    path_content, ondisk_path);
4912 					goto done;
4913 				}
4914 			}
4915 		} else {
4916 			int is_bad_symlink = 0;
4917 			if (te && S_ISLNK(te->mode)) {
4918 				err = install_symlink(&is_bad_symlink,
4919 				    a->worktree, ondisk_path, ie->path,
4920 				    blob, 0, 1, 0, 0, a->repo,
4921 				    a->progress_cb, a->progress_arg);
4922 			} else {
4923 				err = install_blob(a->worktree, ondisk_path,
4924 				    ie->path,
4925 				    te ? te->mode : GOT_DEFAULT_FILE_MODE,
4926 				    got_fileindex_perms_to_st(ie), blob,
4927 				    0, 1, 0, 0, a->repo,
4928 				    a->progress_cb, a->progress_arg);
4929 			}
4930 			if (err)
4931 				goto done;
4932 			if (status == GOT_STATUS_DELETE ||
4933 			    status == GOT_STATUS_MODE_CHANGE) {
4934 				err = got_fileindex_entry_update(ie,
4935 				    a->worktree->root_fd, relpath,
4936 				    blob->id.sha1,
4937 				    a->worktree->base_commit_id->sha1, 1);
4938 				if (err)
4939 					goto done;
4940 			}
4941 			if (is_bad_symlink) {
4942 				got_fileindex_entry_filetype_set(ie,
4943 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
4944 			}
4945 		}
4946 		break;
4947 	}
4948 	default:
4949 		break;
4950 	}
4951 done:
4952 	free(ondisk_path);
4953 	free(path_content);
4954 	free(parent_path);
4955 	free(tree_path);
4956 	if (fd != -1 && close(fd) == -1 && err == NULL)
4957 		err = got_error_from_errno("close");
4958 	if (blob)
4959 		got_object_blob_close(blob);
4960 	if (tree)
4961 		got_object_tree_close(tree);
4962 	free(tree_id);
4963 	if (base_commit)
4964 		got_object_commit_close(base_commit);
4965 	return err;
4966 }
4967 
4968 const struct got_error *
4969 got_worktree_revert(struct got_worktree *worktree,
4970     struct got_pathlist_head *paths,
4971     got_worktree_checkout_cb progress_cb, void *progress_arg,
4972     got_worktree_patch_cb patch_cb, void *patch_arg,
4973     struct got_repository *repo)
4974 {
4975 	struct got_fileindex *fileindex = NULL;
4976 	char *fileindex_path = NULL;
4977 	const struct got_error *err = NULL, *unlockerr = NULL;
4978 	const struct got_error *sync_err = NULL;
4979 	struct got_pathlist_entry *pe;
4980 	struct revert_file_args rfa;
4981 
4982 	err = lock_worktree(worktree, LOCK_EX);
4983 	if (err)
4984 		return err;
4985 
4986 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4987 	if (err)
4988 		goto done;
4989 
4990 	rfa.worktree = worktree;
4991 	rfa.fileindex = fileindex;
4992 	rfa.progress_cb = progress_cb;
4993 	rfa.progress_arg = progress_arg;
4994 	rfa.patch_cb = patch_cb;
4995 	rfa.patch_arg = patch_arg;
4996 	rfa.repo = repo;
4997 	rfa.unlink_added_files = 0;
4998 	TAILQ_FOREACH(pe, paths, entry) {
4999 		err = worktree_status(worktree, pe->path, fileindex, repo,
5000 		    revert_file, &rfa, NULL, NULL, 1, 0);
5001 		if (err)
5002 			break;
5003 	}
5004 	sync_err = sync_fileindex(fileindex, fileindex_path);
5005 	if (sync_err && err == NULL)
5006 		err = sync_err;
5007 done:
5008 	free(fileindex_path);
5009 	if (fileindex)
5010 		got_fileindex_free(fileindex);
5011 	unlockerr = lock_worktree(worktree, LOCK_SH);
5012 	if (unlockerr && err == NULL)
5013 		err = unlockerr;
5014 	return err;
5015 }
5016 
5017 static void
5018 free_commitable(struct got_commitable *ct)
5019 {
5020 	free(ct->path);
5021 	free(ct->in_repo_path);
5022 	free(ct->ondisk_path);
5023 	free(ct->blob_id);
5024 	free(ct->base_blob_id);
5025 	free(ct->staged_blob_id);
5026 	free(ct->base_commit_id);
5027 	free(ct);
5028 }
5029 
5030 struct collect_commitables_arg {
5031 	struct got_pathlist_head *commitable_paths;
5032 	struct got_repository *repo;
5033 	struct got_worktree *worktree;
5034 	struct got_fileindex *fileindex;
5035 	int have_staged_files;
5036 	int allow_bad_symlinks;
5037 	int diff_header_shown;
5038 	int commit_conflicts;
5039 	FILE *diff_outfile;
5040 	FILE *f1;
5041 	FILE *f2;
5042 };
5043 
5044 /*
5045  * Create a file which contains the target path of a symlink so we can feed
5046  * it as content to the diff engine.
5047  */
5048 static const struct got_error *
5049 get_symlink_target_file(int *fd, int dirfd, const char *de_name,
5050     const char *abspath)
5051 {
5052 	const struct got_error *err = NULL;
5053 	char target_path[PATH_MAX];
5054 	ssize_t target_len, outlen;
5055 
5056 	*fd = -1;
5057 
5058 	if (dirfd != -1) {
5059 		target_len = readlinkat(dirfd, de_name, target_path, PATH_MAX);
5060 		if (target_len == -1)
5061 			return got_error_from_errno2("readlinkat", abspath);
5062 	} else {
5063 		target_len = readlink(abspath, target_path, PATH_MAX);
5064 		if (target_len == -1)
5065 			return got_error_from_errno2("readlink", abspath);
5066 	}
5067 
5068 	*fd = got_opentempfd();
5069 	if (*fd == -1)
5070 		return got_error_from_errno("got_opentempfd");
5071 
5072 	outlen = write(*fd, target_path, target_len);
5073 	if (outlen == -1) {
5074 		err = got_error_from_errno("got_opentempfd");
5075 		goto done;
5076 	}
5077 
5078 	if (lseek(*fd, 0, SEEK_SET) == -1) {
5079 		err = got_error_from_errno2("lseek", abspath);
5080 		goto done;
5081 	}
5082 done:
5083 	if (err) {
5084 		close(*fd);
5085 		*fd = -1;
5086 	}
5087 	return err;
5088 }
5089 
5090 static const struct got_error *
5091 append_ct_diff(struct got_commitable *ct, int *diff_header_shown,
5092     FILE *diff_outfile, FILE *f1, FILE *f2, int dirfd, const char *de_name,
5093     int diff_staged, struct got_repository *repo, struct got_worktree *worktree)
5094 {
5095 	const struct got_error *err = NULL;
5096 	struct got_blob_object *blob1 = NULL;
5097 	int fd = -1, fd1 = -1, fd2 = -1;
5098 	FILE *ondisk_file = NULL;
5099 	char *label1 = NULL;
5100 	struct stat sb;
5101 	off_t size1 = 0;
5102 	int f2_exists = 0;
5103 	char *id_str = NULL;
5104 
5105 	memset(&sb, 0, sizeof(sb));
5106 
5107 	if (diff_staged) {
5108 		if (ct->staged_status != GOT_STATUS_MODIFY &&
5109 		    ct->staged_status != GOT_STATUS_ADD &&
5110 		    ct->staged_status != GOT_STATUS_DELETE)
5111 			return NULL;
5112 	} else {
5113 		if (ct->status != GOT_STATUS_MODIFY &&
5114 		    ct->status != GOT_STATUS_ADD &&
5115 		    ct->status != GOT_STATUS_DELETE &&
5116 		    ct->status != GOT_STATUS_CONFLICT)
5117 			return NULL;
5118 	}
5119 
5120 	err = got_opentemp_truncate(f1);
5121 	if (err)
5122 		return got_error_from_errno("got_opentemp_truncate");
5123 	err = got_opentemp_truncate(f2);
5124 	if (err)
5125 		return got_error_from_errno("got_opentemp_truncate");
5126 
5127 	if (!*diff_header_shown) {
5128 		err = got_object_id_str(&id_str, worktree->base_commit_id);
5129 		if (err)
5130 			return err;
5131 		fprintf(diff_outfile, "diff %s%s\n", diff_staged ? "-s " : "",
5132 		    got_worktree_get_root_path(worktree));
5133 		fprintf(diff_outfile, "commit - %s\n", id_str);
5134 		fprintf(diff_outfile, "path + %s%s\n",
5135 		    got_worktree_get_root_path(worktree),
5136 		    diff_staged ? " (staged changes)" : "");
5137 		*diff_header_shown = 1;
5138 	}
5139 
5140 	if (diff_staged) {
5141 		const char *label1 = NULL, *label2 = NULL;
5142 		switch (ct->staged_status) {
5143 		case GOT_STATUS_MODIFY:
5144 			label1 = ct->path;
5145 			label2 = ct->path;
5146 			break;
5147 		case GOT_STATUS_ADD:
5148 			label2 = ct->path;
5149 			break;
5150 		case GOT_STATUS_DELETE:
5151 			label1 = ct->path;
5152 			break;
5153 		default:
5154 			return got_error(GOT_ERR_FILE_STATUS);
5155 		}
5156 		fd1 = got_opentempfd();
5157 		if (fd1 == -1) {
5158 			err = got_error_from_errno("got_opentempfd");
5159 			goto done;
5160 		}
5161 		fd2 = got_opentempfd();
5162 		if (fd2 == -1) {
5163 			err = got_error_from_errno("got_opentempfd");
5164 			goto done;
5165 		}
5166 		err = got_diff_objects_as_blobs(NULL, NULL, f1, f2,
5167 		    fd1, fd2, ct->base_blob_id, ct->staged_blob_id,
5168 		    label1, label2, GOT_DIFF_ALGORITHM_PATIENCE, 3, 0, 0,
5169 		    NULL, repo, diff_outfile);
5170 		goto done;
5171 	}
5172 
5173 	fd1 = got_opentempfd();
5174 	if (fd1 == -1) {
5175 		err = got_error_from_errno("got_opentempfd");
5176 		goto done;
5177 	}
5178 
5179 	if (ct->status != GOT_STATUS_ADD) {
5180 		err = got_object_open_as_blob(&blob1, repo, ct->base_blob_id,
5181 		    8192, fd1);
5182 		if (err)
5183 			goto done;
5184 	}
5185 
5186 	if (ct->status != GOT_STATUS_DELETE) {
5187 		if (dirfd != -1) {
5188 			fd = openat(dirfd, de_name,
5189 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
5190 			if (fd == -1) {
5191 				if (!got_err_open_nofollow_on_symlink()) {
5192 					err = got_error_from_errno2("openat",
5193 					    ct->ondisk_path);
5194 					goto done;
5195 				}
5196 				err = get_symlink_target_file(&fd, dirfd,
5197 				    de_name, ct->ondisk_path);
5198 				if (err)
5199 					goto done;
5200 			}
5201 		} else {
5202 			fd = open(ct->ondisk_path,
5203 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
5204 			if (fd == -1) {
5205 				if (!got_err_open_nofollow_on_symlink()) {
5206 					err = got_error_from_errno2("open",
5207 					    ct->ondisk_path);
5208 					goto done;
5209 				}
5210 				err = get_symlink_target_file(&fd, dirfd,
5211 				    de_name, ct->ondisk_path);
5212 				if (err)
5213 					goto done;
5214 			}
5215 		}
5216 		if (fstatat(fd, ct->ondisk_path, &sb,
5217 		    AT_SYMLINK_NOFOLLOW) == -1) {
5218 			err = got_error_from_errno2("fstatat", ct->ondisk_path);
5219 			goto done;
5220 		}
5221 		ondisk_file = fdopen(fd, "r");
5222 		if (ondisk_file == NULL) {
5223 			err = got_error_from_errno2("fdopen", ct->ondisk_path);
5224 			goto done;
5225 		}
5226 		fd = -1;
5227 		f2_exists = 1;
5228 	}
5229 
5230 	if (blob1) {
5231 		err = got_object_blob_dump_to_file(&size1, NULL, NULL,
5232 		    f1, blob1);
5233 		if (err)
5234 			goto done;
5235 	}
5236 
5237 	err = got_diff_blob_file(blob1, f1, size1, label1,
5238 	    ondisk_file ? ondisk_file : f2, f2_exists, &sb, ct->path,
5239 	    GOT_DIFF_ALGORITHM_PATIENCE, 3, 0, 0, NULL, diff_outfile);
5240 done:
5241 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
5242 		err = got_error_from_errno("close");
5243 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
5244 		err = got_error_from_errno("close");
5245 	if (blob1)
5246 		got_object_blob_close(blob1);
5247 	if (fd != -1 && close(fd) == -1 && err == NULL)
5248 		err = got_error_from_errno("close");
5249 	if (ondisk_file && fclose(ondisk_file) == EOF && err == NULL)
5250 		err = got_error_from_errno("fclose");
5251 	return err;
5252 }
5253 
5254 static const struct got_error *
5255 collect_commitables(void *arg, unsigned char status,
5256     unsigned char staged_status, const char *relpath,
5257     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5258     struct got_object_id *commit_id, int dirfd, const char *de_name)
5259 {
5260 	struct collect_commitables_arg *a = arg;
5261 	const struct got_error *err = NULL;
5262 	struct got_commitable *ct = NULL;
5263 	struct got_pathlist_entry *new = NULL;
5264 	char *parent_path = NULL, *path = NULL;
5265 	struct stat sb;
5266 
5267 	if (a->have_staged_files) {
5268 		if (staged_status != GOT_STATUS_MODIFY &&
5269 		    staged_status != GOT_STATUS_ADD &&
5270 		    staged_status != GOT_STATUS_DELETE)
5271 			return NULL;
5272 	} else {
5273 		if (status == GOT_STATUS_CONFLICT && !a->commit_conflicts) {
5274 			printf("C  %s\n", relpath);
5275 			return got_error(GOT_ERR_COMMIT_CONFLICT);
5276 		}
5277 
5278 		if (status != GOT_STATUS_MODIFY &&
5279 		    status != GOT_STATUS_MODE_CHANGE &&
5280 		    status != GOT_STATUS_ADD &&
5281 		    status != GOT_STATUS_DELETE &&
5282 		    status != GOT_STATUS_CONFLICT)
5283 			return NULL;
5284 	}
5285 
5286 	if (asprintf(&path, "/%s", relpath) == -1) {
5287 		err = got_error_from_errno("asprintf");
5288 		goto done;
5289 	}
5290 	if (strcmp(path, "/") == 0) {
5291 		parent_path = strdup("");
5292 		if (parent_path == NULL)
5293 			return got_error_from_errno("strdup");
5294 	} else {
5295 		err = got_path_dirname(&parent_path, path);
5296 		if (err)
5297 			return err;
5298 	}
5299 
5300 	ct = calloc(1, sizeof(*ct));
5301 	if (ct == NULL) {
5302 		err = got_error_from_errno("calloc");
5303 		goto done;
5304 	}
5305 
5306 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
5307 	    relpath) == -1) {
5308 		err = got_error_from_errno("asprintf");
5309 		goto done;
5310 	}
5311 
5312 	if (staged_status == GOT_STATUS_ADD ||
5313 	    staged_status == GOT_STATUS_MODIFY) {
5314 		struct got_fileindex_entry *ie;
5315 		ie = got_fileindex_entry_get(a->fileindex, path, strlen(path));
5316 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
5317 		case GOT_FILEIDX_MODE_REGULAR_FILE:
5318 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
5319 			ct->mode = S_IFREG;
5320 			break;
5321 		case GOT_FILEIDX_MODE_SYMLINK:
5322 			ct->mode = S_IFLNK;
5323 			break;
5324 		default:
5325 			err = got_error_path(path, GOT_ERR_BAD_FILETYPE);
5326 			goto done;
5327 		}
5328 		ct->mode |= got_fileindex_entry_perms_get(ie);
5329 	} else if (status != GOT_STATUS_DELETE &&
5330 	    staged_status != GOT_STATUS_DELETE) {
5331 		if (dirfd != -1) {
5332 			if (fstatat(dirfd, de_name, &sb,
5333 			    AT_SYMLINK_NOFOLLOW) == -1) {
5334 				err = got_error_from_errno2("fstatat",
5335 				    ct->ondisk_path);
5336 				goto done;
5337 			}
5338 		} else if (lstat(ct->ondisk_path, &sb) == -1) {
5339 			err = got_error_from_errno2("lstat", ct->ondisk_path);
5340 			goto done;
5341 		}
5342 		ct->mode = sb.st_mode;
5343 	}
5344 
5345 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
5346 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
5347 	    relpath) == -1) {
5348 		err = got_error_from_errno("asprintf");
5349 		goto done;
5350 	}
5351 
5352 	if (S_ISLNK(ct->mode) && staged_status == GOT_STATUS_NO_CHANGE &&
5353 	    status == GOT_STATUS_ADD && !a->allow_bad_symlinks) {
5354 		int is_bad_symlink;
5355 		char target_path[PATH_MAX];
5356 		ssize_t target_len;
5357 		target_len = readlink(ct->ondisk_path, target_path,
5358 		    sizeof(target_path));
5359 		if (target_len == -1) {
5360 			err = got_error_from_errno2("readlink",
5361 			    ct->ondisk_path);
5362 			goto done;
5363 		}
5364 		err = is_bad_symlink_target(&is_bad_symlink, target_path,
5365 		    target_len, ct->ondisk_path, a->worktree->root_path);
5366 		if (err)
5367 			goto done;
5368 		if (is_bad_symlink) {
5369 			err = got_error_path(ct->ondisk_path,
5370 			    GOT_ERR_BAD_SYMLINK);
5371 			goto done;
5372 		}
5373 	}
5374 
5375 
5376 	ct->status = status;
5377 	ct->staged_status = staged_status;
5378 	ct->blob_id = NULL; /* will be filled in when blob gets created */
5379 	if (ct->status != GOT_STATUS_ADD &&
5380 	    ct->staged_status != GOT_STATUS_ADD) {
5381 		ct->base_blob_id = got_object_id_dup(blob_id);
5382 		if (ct->base_blob_id == NULL) {
5383 			err = got_error_from_errno("got_object_id_dup");
5384 			goto done;
5385 		}
5386 		ct->base_commit_id = got_object_id_dup(commit_id);
5387 		if (ct->base_commit_id == NULL) {
5388 			err = got_error_from_errno("got_object_id_dup");
5389 			goto done;
5390 		}
5391 	}
5392 	if (ct->staged_status == GOT_STATUS_ADD ||
5393 	    ct->staged_status == GOT_STATUS_MODIFY) {
5394 		ct->staged_blob_id = got_object_id_dup(staged_blob_id);
5395 		if (ct->staged_blob_id == NULL) {
5396 			err = got_error_from_errno("got_object_id_dup");
5397 			goto done;
5398 		}
5399 	}
5400 	ct->path = strdup(path);
5401 	if (ct->path == NULL) {
5402 		err = got_error_from_errno("strdup");
5403 		goto done;
5404 	}
5405 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
5406 	if (err)
5407 		goto done;
5408 
5409 	if (a->diff_outfile && ct && new != NULL) {
5410 		err = append_ct_diff(ct, &a->diff_header_shown,
5411 		    a->diff_outfile, a->f1, a->f2, dirfd, de_name,
5412 		    a->have_staged_files, a->repo, a->worktree);
5413 		if (err)
5414 			goto done;
5415 	}
5416 done:
5417 	if (ct && (err || new == NULL))
5418 		free_commitable(ct);
5419 	free(parent_path);
5420 	free(path);
5421 	return err;
5422 }
5423 
5424 static const struct got_error *write_tree(struct got_object_id **, int *,
5425     struct got_tree_object *, const char *, struct got_pathlist_head *,
5426     got_worktree_status_cb status_cb, void *status_arg,
5427     struct got_repository *);
5428 
5429 static const struct got_error *
5430 write_subtree(struct got_object_id **new_subtree_id, int *nentries,
5431     struct got_tree_entry *te, const char *parent_path,
5432     struct got_pathlist_head *commitable_paths,
5433     got_worktree_status_cb status_cb, void *status_arg,
5434     struct got_repository *repo)
5435 {
5436 	const struct got_error *err = NULL;
5437 	struct got_tree_object *subtree;
5438 	char *subpath;
5439 
5440 	if (asprintf(&subpath, "%s%s%s", parent_path,
5441 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
5442 		return got_error_from_errno("asprintf");
5443 
5444 	err = got_object_open_as_tree(&subtree, repo, &te->id);
5445 	if (err)
5446 		return err;
5447 
5448 	err = write_tree(new_subtree_id, nentries, subtree, subpath,
5449 	    commitable_paths, status_cb, status_arg, repo);
5450 	got_object_tree_close(subtree);
5451 	free(subpath);
5452 	return err;
5453 }
5454 
5455 static const struct got_error *
5456 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
5457 {
5458 	const struct got_error *err = NULL;
5459 	char *ct_parent_path = NULL;
5460 
5461 	*match = 0;
5462 
5463 	if (strchr(ct->in_repo_path, '/') == NULL) {
5464 		*match = got_path_is_root_dir(path);
5465 		return NULL;
5466 	}
5467 
5468 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
5469 	if (err)
5470 		return err;
5471 	*match = (strcmp(path, ct_parent_path) == 0);
5472 	free(ct_parent_path);
5473 	return err;
5474 }
5475 
5476 static mode_t
5477 get_ct_file_mode(struct got_commitable *ct)
5478 {
5479 	if (S_ISLNK(ct->mode))
5480 		return S_IFLNK;
5481 
5482 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
5483 }
5484 
5485 static const struct got_error *
5486 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
5487     struct got_tree_entry *te, struct got_commitable *ct)
5488 {
5489 	const struct got_error *err = NULL;
5490 
5491 	*new_te = NULL;
5492 
5493 	err = got_object_tree_entry_dup(new_te, te);
5494 	if (err)
5495 		goto done;
5496 
5497 	(*new_te)->mode = get_ct_file_mode(ct);
5498 
5499 	if (ct->staged_status == GOT_STATUS_MODIFY)
5500 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5501 		    sizeof((*new_te)->id));
5502 	else
5503 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5504 done:
5505 	if (err && *new_te) {
5506 		free(*new_te);
5507 		*new_te = NULL;
5508 	}
5509 	return err;
5510 }
5511 
5512 static const struct got_error *
5513 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
5514     struct got_commitable *ct)
5515 {
5516 	const struct got_error *err = NULL;
5517 	char *ct_name = NULL;
5518 
5519 	 *new_te = NULL;
5520 
5521 	*new_te = calloc(1, sizeof(**new_te));
5522 	if (*new_te == NULL)
5523 		return got_error_from_errno("calloc");
5524 
5525 	err = got_path_basename(&ct_name, ct->path);
5526 	if (err)
5527 		goto done;
5528 	if (strlcpy((*new_te)->name, ct_name, sizeof((*new_te)->name)) >=
5529 	    sizeof((*new_te)->name)) {
5530 		err = got_error(GOT_ERR_NO_SPACE);
5531 		goto done;
5532 	}
5533 
5534 	(*new_te)->mode = get_ct_file_mode(ct);
5535 
5536 	if (ct->staged_status == GOT_STATUS_ADD)
5537 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5538 		    sizeof((*new_te)->id));
5539 	else
5540 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5541 done:
5542 	free(ct_name);
5543 	if (err && *new_te) {
5544 		free(*new_te);
5545 		*new_te = NULL;
5546 	}
5547 	return err;
5548 }
5549 
5550 static const struct got_error *
5551 insert_tree_entry(struct got_tree_entry *new_te,
5552     struct got_pathlist_head *paths)
5553 {
5554 	const struct got_error *err = NULL;
5555 	struct got_pathlist_entry *new_pe;
5556 
5557 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
5558 	if (err)
5559 		return err;
5560 	if (new_pe == NULL)
5561 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
5562 	return NULL;
5563 }
5564 
5565 static const struct got_error *
5566 report_ct_status(struct got_commitable *ct,
5567     got_worktree_status_cb status_cb, void *status_arg)
5568 {
5569 	const char *ct_path = ct->path;
5570 	unsigned char status;
5571 
5572 	if (status_cb == NULL) /* no commit progress output desired */
5573 		return NULL;
5574 
5575 	while (ct_path[0] == '/')
5576 		ct_path++;
5577 
5578 	if (ct->staged_status != GOT_STATUS_NO_CHANGE)
5579 		status = ct->staged_status;
5580 	else
5581 		status = ct->status;
5582 
5583 	return (*status_cb)(status_arg, status, GOT_STATUS_NO_CHANGE,
5584 	    ct_path, ct->blob_id, NULL, NULL, -1, NULL);
5585 }
5586 
5587 static const struct got_error *
5588 match_modified_subtree(int *modified, struct got_tree_entry *te,
5589     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
5590 {
5591 	const struct got_error *err = NULL;
5592 	struct got_pathlist_entry *pe;
5593 	char *te_path;
5594 
5595 	*modified = 0;
5596 
5597 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
5598 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
5599 	    te->name) == -1)
5600 		return got_error_from_errno("asprintf");
5601 
5602 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5603 		struct got_commitable *ct = pe->data;
5604 		*modified = got_path_is_child(ct->in_repo_path, te_path,
5605 		    strlen(te_path));
5606 		if (*modified)
5607 			break;
5608 	}
5609 
5610 	free(te_path);
5611 	return err;
5612 }
5613 
5614 static const struct got_error *
5615 match_deleted_or_modified_ct(struct got_commitable **ctp,
5616     struct got_tree_entry *te, const char *base_tree_path,
5617     struct got_pathlist_head *commitable_paths)
5618 {
5619 	const struct got_error *err = NULL;
5620 	struct got_pathlist_entry *pe;
5621 
5622 	*ctp = NULL;
5623 
5624 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5625 		struct got_commitable *ct = pe->data;
5626 		char *ct_name = NULL;
5627 		int path_matches;
5628 
5629 		if (ct->staged_status == GOT_STATUS_NO_CHANGE) {
5630 			if (ct->status != GOT_STATUS_MODIFY &&
5631 			    ct->status != GOT_STATUS_MODE_CHANGE &&
5632 			    ct->status != GOT_STATUS_DELETE &&
5633 			    ct->status != GOT_STATUS_CONFLICT)
5634 				continue;
5635 		} else {
5636 			if (ct->staged_status != GOT_STATUS_MODIFY &&
5637 			    ct->staged_status != GOT_STATUS_DELETE)
5638 				continue;
5639 		}
5640 
5641 		if (got_object_id_cmp(ct->base_blob_id, &te->id) != 0)
5642 			continue;
5643 
5644 		err = match_ct_parent_path(&path_matches, ct, base_tree_path);
5645 		if (err)
5646 			return err;
5647 		if (!path_matches)
5648 			continue;
5649 
5650 		err = got_path_basename(&ct_name, pe->path);
5651 		if (err)
5652 			return err;
5653 
5654 		if (strcmp(te->name, ct_name) != 0) {
5655 			free(ct_name);
5656 			continue;
5657 		}
5658 		free(ct_name);
5659 
5660 		*ctp = ct;
5661 		break;
5662 	}
5663 
5664 	return err;
5665 }
5666 
5667 static const struct got_error *
5668 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
5669     const char *child_path, const char *path_base_tree,
5670     struct got_pathlist_head *commitable_paths,
5671     got_worktree_status_cb status_cb, void *status_arg,
5672     struct got_repository *repo)
5673 {
5674 	const struct got_error *err = NULL;
5675 	struct got_tree_entry *new_te;
5676 	char *subtree_path;
5677 	struct got_object_id *id = NULL;
5678 	int nentries;
5679 
5680 	*new_tep = NULL;
5681 
5682 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
5683 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
5684 	    child_path) == -1)
5685 		return got_error_from_errno("asprintf");
5686 
5687 	new_te = calloc(1, sizeof(*new_te));
5688 	if (new_te == NULL)
5689 		return got_error_from_errno("calloc");
5690 	new_te->mode = S_IFDIR;
5691 
5692 	if (strlcpy(new_te->name, child_path, sizeof(new_te->name)) >=
5693 	    sizeof(new_te->name)) {
5694 		err = got_error(GOT_ERR_NO_SPACE);
5695 		goto done;
5696 	}
5697 	err = write_tree(&id, &nentries, NULL, subtree_path,
5698 	    commitable_paths, status_cb, status_arg, repo);
5699 	if (err) {
5700 		free(new_te);
5701 		goto done;
5702 	}
5703 	memcpy(&new_te->id, id, sizeof(new_te->id));
5704 done:
5705 	free(id);
5706 	free(subtree_path);
5707 	if (err == NULL)
5708 		*new_tep = new_te;
5709 	return err;
5710 }
5711 
5712 static const struct got_error *
5713 write_tree(struct got_object_id **new_tree_id, int *nentries,
5714     struct got_tree_object *base_tree, const char *path_base_tree,
5715     struct got_pathlist_head *commitable_paths,
5716     got_worktree_status_cb status_cb, void *status_arg,
5717     struct got_repository *repo)
5718 {
5719 	const struct got_error *err = NULL;
5720 	struct got_pathlist_head paths;
5721 	struct got_tree_entry *te, *new_te = NULL;
5722 	struct got_pathlist_entry *pe;
5723 
5724 	TAILQ_INIT(&paths);
5725 	*nentries = 0;
5726 
5727 	/* Insert, and recurse into, newly added entries first. */
5728 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5729 		struct got_commitable *ct = pe->data;
5730 		char *child_path = NULL, *slash;
5731 
5732 		if ((ct->status != GOT_STATUS_ADD &&
5733 		    ct->staged_status != GOT_STATUS_ADD) ||
5734 		    (ct->flags & GOT_COMMITABLE_ADDED))
5735 			continue;
5736 
5737 		if (!got_path_is_child(ct->in_repo_path, path_base_tree,
5738 		    strlen(path_base_tree)))
5739 			continue;
5740 
5741 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
5742 		    ct->in_repo_path);
5743 		if (err)
5744 			goto done;
5745 
5746 		slash = strchr(child_path, '/');
5747 		if (slash == NULL) {
5748 			err = alloc_added_blob_tree_entry(&new_te, ct);
5749 			if (err)
5750 				goto done;
5751 			err = report_ct_status(ct, status_cb, status_arg);
5752 			if (err)
5753 				goto done;
5754 			ct->flags |= GOT_COMMITABLE_ADDED;
5755 			err = insert_tree_entry(new_te, &paths);
5756 			if (err)
5757 				goto done;
5758 			(*nentries)++;
5759 		} else {
5760 			*slash = '\0'; /* trim trailing path components */
5761 			if (base_tree == NULL ||
5762 			    got_object_tree_find_entry(base_tree, child_path)
5763 			    == NULL) {
5764 				err = make_subtree_for_added_blob(&new_te,
5765 				    child_path, path_base_tree,
5766 				    commitable_paths, status_cb, status_arg,
5767 				    repo);
5768 				if (err)
5769 					goto done;
5770 				err = insert_tree_entry(new_te, &paths);
5771 				if (err)
5772 					goto done;
5773 				(*nentries)++;
5774 			}
5775 		}
5776 	}
5777 
5778 	if (base_tree) {
5779 		int i, nbase_entries;
5780 		/* Handle modified and deleted entries. */
5781 		nbase_entries = got_object_tree_get_nentries(base_tree);
5782 		for (i = 0; i < nbase_entries; i++) {
5783 			struct got_commitable *ct = NULL;
5784 
5785 			te = got_object_tree_get_entry(base_tree, i);
5786 			if (got_object_tree_entry_is_submodule(te)) {
5787 				/* Entry is a submodule; just copy it. */
5788 				err = got_object_tree_entry_dup(&new_te, te);
5789 				if (err)
5790 					goto done;
5791 				err = insert_tree_entry(new_te, &paths);
5792 				if (err)
5793 					goto done;
5794 				(*nentries)++;
5795 				continue;
5796 			}
5797 
5798 			if (S_ISDIR(te->mode)) {
5799 				int modified;
5800 				err = got_object_tree_entry_dup(&new_te, te);
5801 				if (err)
5802 					goto done;
5803 				err = match_modified_subtree(&modified, te,
5804 				    path_base_tree, commitable_paths);
5805 				if (err)
5806 					goto done;
5807 				/* Avoid recursion into unmodified subtrees. */
5808 				if (modified) {
5809 					struct got_object_id *new_id;
5810 					int nsubentries;
5811 					err = write_subtree(&new_id,
5812 					    &nsubentries, te,
5813 					    path_base_tree, commitable_paths,
5814 					    status_cb, status_arg, repo);
5815 					if (err)
5816 						goto done;
5817 					if (nsubentries == 0) {
5818 						/* All entries were deleted. */
5819 						free(new_id);
5820 						continue;
5821 					}
5822 					memcpy(&new_te->id, new_id,
5823 					    sizeof(new_te->id));
5824 					free(new_id);
5825 				}
5826 				err = insert_tree_entry(new_te, &paths);
5827 				if (err)
5828 					goto done;
5829 				(*nentries)++;
5830 				continue;
5831 			}
5832 
5833 			err = match_deleted_or_modified_ct(&ct, te,
5834 			    path_base_tree, commitable_paths);
5835 			if (err)
5836 				goto done;
5837 			if (ct) {
5838 				/* NB: Deleted entries get dropped here. */
5839 				if (ct->status == GOT_STATUS_MODIFY ||
5840 				    ct->status == GOT_STATUS_MODE_CHANGE ||
5841 				    ct->status == GOT_STATUS_CONFLICT ||
5842 				    ct->staged_status == GOT_STATUS_MODIFY) {
5843 					err = alloc_modified_blob_tree_entry(
5844 					    &new_te, te, ct);
5845 					if (err)
5846 						goto done;
5847 					err = insert_tree_entry(new_te, &paths);
5848 					if (err)
5849 						goto done;
5850 					(*nentries)++;
5851 				}
5852 				err = report_ct_status(ct, status_cb,
5853 				    status_arg);
5854 				if (err)
5855 					goto done;
5856 			} else {
5857 				/* Entry is unchanged; just copy it. */
5858 				err = got_object_tree_entry_dup(&new_te, te);
5859 				if (err)
5860 					goto done;
5861 				err = insert_tree_entry(new_te, &paths);
5862 				if (err)
5863 					goto done;
5864 				(*nentries)++;
5865 			}
5866 		}
5867 	}
5868 
5869 	/* Write new list of entries; deleted entries have been dropped. */
5870 	err = got_object_tree_create(new_tree_id, &paths, *nentries, repo);
5871 done:
5872 	got_pathlist_free(&paths, GOT_PATHLIST_FREE_NONE);
5873 	return err;
5874 }
5875 
5876 static const struct got_error *
5877 update_fileindex_after_commit(struct got_worktree *worktree,
5878     struct got_pathlist_head *commitable_paths,
5879     struct got_object_id *new_base_commit_id,
5880     struct got_fileindex *fileindex, int have_staged_files)
5881 {
5882 	const struct got_error *err = NULL;
5883 	struct got_pathlist_entry *pe;
5884 	char *relpath = NULL;
5885 
5886 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5887 		struct got_fileindex_entry *ie;
5888 		struct got_commitable *ct = pe->data;
5889 
5890 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
5891 
5892 		err = got_path_skip_common_ancestor(&relpath,
5893 		    worktree->root_path, ct->ondisk_path);
5894 		if (err)
5895 			goto done;
5896 
5897 		if (ie) {
5898 			if (ct->status == GOT_STATUS_DELETE ||
5899 			    ct->staged_status == GOT_STATUS_DELETE) {
5900 				got_fileindex_entry_remove(fileindex, ie);
5901 			} else if (ct->staged_status == GOT_STATUS_ADD ||
5902 			    ct->staged_status == GOT_STATUS_MODIFY) {
5903 				got_fileindex_entry_stage_set(ie,
5904 				    GOT_FILEIDX_STAGE_NONE);
5905 				got_fileindex_entry_staged_filetype_set(ie, 0);
5906 
5907 				err = got_fileindex_entry_update(ie,
5908 				    worktree->root_fd, relpath,
5909 				    ct->staged_blob_id->sha1,
5910 				    new_base_commit_id->sha1,
5911 				    !have_staged_files);
5912 			} else
5913 				err = got_fileindex_entry_update(ie,
5914 				    worktree->root_fd, relpath,
5915 				    ct->blob_id->sha1,
5916 				    new_base_commit_id->sha1,
5917 				    !have_staged_files);
5918 		} else {
5919 			err = got_fileindex_entry_alloc(&ie, pe->path);
5920 			if (err)
5921 				goto done;
5922 			err = got_fileindex_entry_update(ie,
5923 			    worktree->root_fd, relpath, ct->blob_id->sha1,
5924 			    new_base_commit_id->sha1, 1);
5925 			if (err) {
5926 				got_fileindex_entry_free(ie);
5927 				goto done;
5928 			}
5929 			err = got_fileindex_entry_add(fileindex, ie);
5930 			if (err) {
5931 				got_fileindex_entry_free(ie);
5932 				goto done;
5933 			}
5934 		}
5935 		free(relpath);
5936 		relpath = NULL;
5937 	}
5938 done:
5939 	free(relpath);
5940 	return err;
5941 }
5942 
5943 
5944 static const struct got_error *
5945 check_out_of_date(const char *in_repo_path, unsigned char status,
5946     unsigned char staged_status, struct got_object_id *base_blob_id,
5947     struct got_object_id *base_commit_id,
5948     struct got_object_id *head_commit_id, struct got_repository *repo,
5949     int ood_errcode)
5950 {
5951 	const struct got_error *err = NULL;
5952 	struct got_commit_object *commit = NULL;
5953 	struct got_object_id *id = NULL;
5954 
5955 	if (status != GOT_STATUS_ADD && staged_status != GOT_STATUS_ADD) {
5956 		/* Trivial case: base commit == head commit */
5957 		if (got_object_id_cmp(base_commit_id, head_commit_id) == 0)
5958 			return NULL;
5959 		/*
5960 		 * Ensure file content which local changes were based
5961 		 * on matches file content in the branch head.
5962 		 */
5963 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
5964 		if (err)
5965 			goto done;
5966 		err = got_object_id_by_path(&id, repo, commit, in_repo_path);
5967 		if (err) {
5968 			if (err->code == GOT_ERR_NO_TREE_ENTRY)
5969 				err = got_error(ood_errcode);
5970 			goto done;
5971 		} else if (got_object_id_cmp(id, base_blob_id) != 0)
5972 			err = got_error(ood_errcode);
5973 	} else {
5974 		/* Require that added files don't exist in the branch head. */
5975 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
5976 		if (err)
5977 			goto done;
5978 		err = got_object_id_by_path(&id, repo, commit, in_repo_path);
5979 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
5980 			goto done;
5981 		err = id ? got_error(ood_errcode) : NULL;
5982 	}
5983 done:
5984 	free(id);
5985 	if (commit)
5986 		got_object_commit_close(commit);
5987 	return err;
5988 }
5989 
5990 static const struct got_error *
5991 commit_worktree(struct got_object_id **new_commit_id,
5992     struct got_pathlist_head *commitable_paths,
5993     struct got_object_id *head_commit_id,
5994     struct got_object_id *parent_id2,
5995     struct got_worktree *worktree,
5996     const char *author, const char *committer, char *diff_path,
5997     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
5998     got_worktree_status_cb status_cb, void *status_arg,
5999     struct got_repository *repo)
6000 {
6001 	const struct got_error *err = NULL, *unlockerr = NULL;
6002 	struct got_pathlist_entry *pe;
6003 	const char *head_ref_name = NULL;
6004 	struct got_commit_object *head_commit = NULL;
6005 	struct got_reference *head_ref2 = NULL;
6006 	struct got_object_id *head_commit_id2 = NULL;
6007 	struct got_tree_object *head_tree = NULL;
6008 	struct got_object_id *new_tree_id = NULL;
6009 	int nentries, nparents = 0;
6010 	struct got_object_id_queue parent_ids;
6011 	struct got_object_qid *pid = NULL;
6012 	char *logmsg = NULL;
6013 	time_t timestamp;
6014 
6015 	*new_commit_id = NULL;
6016 
6017 	STAILQ_INIT(&parent_ids);
6018 
6019 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
6020 	if (err)
6021 		goto done;
6022 
6023 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
6024 	if (err)
6025 		goto done;
6026 
6027 	if (commit_msg_cb != NULL) {
6028 		err = commit_msg_cb(commitable_paths, diff_path,
6029 		    &logmsg, commit_arg);
6030 		if (err)
6031 			goto done;
6032 	}
6033 
6034 	if (logmsg == NULL || strlen(logmsg) == 0) {
6035 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
6036 		goto done;
6037 	}
6038 
6039 	/* Create blobs from added and modified files and record their IDs. */
6040 	TAILQ_FOREACH(pe, commitable_paths, entry) {
6041 		struct got_commitable *ct = pe->data;
6042 		char *ondisk_path;
6043 
6044 		/* Blobs for staged files already exist. */
6045 		if (ct->staged_status == GOT_STATUS_ADD ||
6046 		    ct->staged_status == GOT_STATUS_MODIFY)
6047 			continue;
6048 
6049 		if (ct->status != GOT_STATUS_ADD &&
6050 		    ct->status != GOT_STATUS_MODIFY &&
6051 		    ct->status != GOT_STATUS_MODE_CHANGE &&
6052 		    ct->status != GOT_STATUS_CONFLICT)
6053 			continue;
6054 
6055 		if (asprintf(&ondisk_path, "%s/%s",
6056 		    worktree->root_path, pe->path) == -1) {
6057 			err = got_error_from_errno("asprintf");
6058 			goto done;
6059 		}
6060 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
6061 		free(ondisk_path);
6062 		if (err)
6063 			goto done;
6064 	}
6065 
6066 	/* Recursively write new tree objects. */
6067 	err = write_tree(&new_tree_id, &nentries, head_tree, "/",
6068 	    commitable_paths, status_cb, status_arg, repo);
6069 	if (err)
6070 		goto done;
6071 
6072 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
6073 	if (err)
6074 		goto done;
6075 	STAILQ_INSERT_TAIL(&parent_ids, pid, entry);
6076 	nparents++;
6077 	if (parent_id2) {
6078 		err = got_object_qid_alloc(&pid, parent_id2);
6079 		if (err)
6080 			goto done;
6081 		STAILQ_INSERT_TAIL(&parent_ids, pid, entry);
6082 		nparents++;
6083 	}
6084 	timestamp = time(NULL);
6085 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
6086 	    nparents, author, timestamp, committer, timestamp, logmsg, repo);
6087 	if (logmsg != NULL)
6088 		free(logmsg);
6089 	if (err)
6090 		goto done;
6091 
6092 	/* Check if a concurrent commit to our branch has occurred. */
6093 	head_ref_name = got_worktree_get_head_ref_name(worktree);
6094 	if (head_ref_name == NULL) {
6095 		err = got_error_from_errno("got_worktree_get_head_ref_name");
6096 		goto done;
6097 	}
6098 	/* Lock the reference here to prevent concurrent modification. */
6099 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
6100 	if (err)
6101 		goto done;
6102 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
6103 	if (err)
6104 		goto done;
6105 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
6106 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
6107 		goto done;
6108 	}
6109 	/* Update branch head in repository. */
6110 	err = got_ref_change_ref(head_ref2, *new_commit_id);
6111 	if (err)
6112 		goto done;
6113 	err = got_ref_write(head_ref2, repo);
6114 	if (err)
6115 		goto done;
6116 
6117 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
6118 	if (err)
6119 		goto done;
6120 
6121 	err = ref_base_commit(worktree, repo);
6122 	if (err)
6123 		goto done;
6124 done:
6125 	got_object_id_queue_free(&parent_ids);
6126 	if (head_tree)
6127 		got_object_tree_close(head_tree);
6128 	if (head_commit)
6129 		got_object_commit_close(head_commit);
6130 	free(head_commit_id2);
6131 	if (head_ref2) {
6132 		unlockerr = got_ref_unlock(head_ref2);
6133 		if (unlockerr && err == NULL)
6134 			err = unlockerr;
6135 		got_ref_close(head_ref2);
6136 	}
6137 	return err;
6138 }
6139 
6140 static const struct got_error *
6141 check_path_is_commitable(const char *path,
6142     struct got_pathlist_head *commitable_paths)
6143 {
6144 	struct got_pathlist_entry *cpe = NULL;
6145 	size_t path_len = strlen(path);
6146 
6147 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
6148 		struct got_commitable *ct = cpe->data;
6149 		const char *ct_path = ct->path;
6150 
6151 		while (ct_path[0] == '/')
6152 			ct_path++;
6153 
6154 		if (strcmp(path, ct_path) == 0 ||
6155 		    got_path_is_child(ct_path, path, path_len))
6156 			break;
6157 	}
6158 
6159 	if (cpe == NULL)
6160 		return got_error_path(path, GOT_ERR_BAD_PATH);
6161 
6162 	return NULL;
6163 }
6164 
6165 static const struct got_error *
6166 check_staged_file(void *arg, struct got_fileindex_entry *ie)
6167 {
6168 	int *have_staged_files = arg;
6169 
6170 	if (got_fileindex_entry_stage_get(ie) != GOT_FILEIDX_STAGE_NONE) {
6171 		*have_staged_files = 1;
6172 		return got_error(GOT_ERR_CANCELLED);
6173 	}
6174 
6175 	return NULL;
6176 }
6177 
6178 static const struct got_error *
6179 check_non_staged_files(struct got_fileindex *fileindex,
6180     struct got_pathlist_head *paths)
6181 {
6182 	struct got_pathlist_entry *pe;
6183 	struct got_fileindex_entry *ie;
6184 
6185 	TAILQ_FOREACH(pe, paths, entry) {
6186 		if (pe->path[0] == '\0')
6187 			continue;
6188 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
6189 		if (ie == NULL)
6190 			return got_error_path(pe->path, GOT_ERR_BAD_PATH);
6191 		if (got_fileindex_entry_stage_get(ie) == GOT_FILEIDX_STAGE_NONE)
6192 			return got_error_path(pe->path,
6193 			    GOT_ERR_FILE_NOT_STAGED);
6194 	}
6195 
6196 	return NULL;
6197 }
6198 
6199 const struct got_error *
6200 got_worktree_commit(struct got_object_id **new_commit_id,
6201     struct got_worktree *worktree, struct got_pathlist_head *paths,
6202     const char *author, const char *committer, int allow_bad_symlinks,
6203     int show_diff, int commit_conflicts,
6204     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
6205     got_worktree_status_cb status_cb, void *status_arg,
6206     struct got_repository *repo)
6207 {
6208 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
6209 	struct got_fileindex *fileindex = NULL;
6210 	char *fileindex_path = NULL;
6211 	struct got_pathlist_head commitable_paths;
6212 	struct collect_commitables_arg cc_arg;
6213 	struct got_pathlist_entry *pe;
6214 	struct got_reference *head_ref = NULL;
6215 	struct got_object_id *head_commit_id = NULL;
6216 	char *diff_path = NULL;
6217 	int have_staged_files = 0;
6218 
6219 	*new_commit_id = NULL;
6220 
6221 	memset(&cc_arg, 0, sizeof(cc_arg));
6222 	TAILQ_INIT(&commitable_paths);
6223 
6224 	err = lock_worktree(worktree, LOCK_EX);
6225 	if (err)
6226 		goto done;
6227 
6228 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
6229 	if (err)
6230 		goto done;
6231 
6232 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
6233 	if (err)
6234 		goto done;
6235 
6236 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
6237 	if (err)
6238 		goto done;
6239 
6240 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
6241 	    &have_staged_files);
6242 	if (err && err->code != GOT_ERR_CANCELLED)
6243 		goto done;
6244 	if (have_staged_files) {
6245 		err = check_non_staged_files(fileindex, paths);
6246 		if (err)
6247 			goto done;
6248 	}
6249 
6250 	cc_arg.commitable_paths = &commitable_paths;
6251 	cc_arg.worktree = worktree;
6252 	cc_arg.fileindex = fileindex;
6253 	cc_arg.repo = repo;
6254 	cc_arg.have_staged_files = have_staged_files;
6255 	cc_arg.allow_bad_symlinks = allow_bad_symlinks;
6256 	cc_arg.diff_header_shown = 0;
6257 	cc_arg.commit_conflicts = commit_conflicts;
6258 	if (show_diff) {
6259 		err = got_opentemp_named(&diff_path, &cc_arg.diff_outfile,
6260 		    GOT_TMPDIR_STR "/got", ".diff");
6261 		if (err)
6262 			goto done;
6263 		cc_arg.f1 = got_opentemp();
6264 		if (cc_arg.f1 == NULL) {
6265 			err = got_error_from_errno("got_opentemp");
6266 			goto done;
6267 		}
6268 		cc_arg.f2 = got_opentemp();
6269 		if (cc_arg.f2 == NULL) {
6270 			err = got_error_from_errno("got_opentemp");
6271 			goto done;
6272 		}
6273 	}
6274 
6275 	TAILQ_FOREACH(pe, paths, entry) {
6276 		err = worktree_status(worktree, pe->path, fileindex, repo,
6277 		    collect_commitables, &cc_arg, NULL, NULL, 0, 0);
6278 		if (err)
6279 			goto done;
6280 	}
6281 
6282 	if (show_diff) {
6283 		if (fflush(cc_arg.diff_outfile) == EOF) {
6284 			err = got_error_from_errno("fflush");
6285 			goto done;
6286 		}
6287 	}
6288 
6289 	if (TAILQ_EMPTY(&commitable_paths)) {
6290 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
6291 		goto done;
6292 	}
6293 
6294 	TAILQ_FOREACH(pe, paths, entry) {
6295 		err = check_path_is_commitable(pe->path, &commitable_paths);
6296 		if (err)
6297 			goto done;
6298 	}
6299 
6300 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
6301 		struct got_commitable *ct = pe->data;
6302 		const char *ct_path = ct->in_repo_path;
6303 
6304 		while (ct_path[0] == '/')
6305 			ct_path++;
6306 		err = check_out_of_date(ct_path, ct->status,
6307 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
6308 		    head_commit_id, repo, GOT_ERR_COMMIT_OUT_OF_DATE);
6309 		if (err)
6310 			goto done;
6311 
6312 	}
6313 
6314 	err = commit_worktree(new_commit_id, &commitable_paths,
6315 	    head_commit_id, NULL, worktree, author, committer,
6316 	    (diff_path && cc_arg.diff_header_shown) ? diff_path : NULL,
6317 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
6318 	if (err)
6319 		goto done;
6320 
6321 	err = update_fileindex_after_commit(worktree, &commitable_paths,
6322 	    *new_commit_id, fileindex, have_staged_files);
6323 	sync_err = sync_fileindex(fileindex, fileindex_path);
6324 	if (sync_err && err == NULL)
6325 		err = sync_err;
6326 done:
6327 	if (fileindex)
6328 		got_fileindex_free(fileindex);
6329 	free(fileindex_path);
6330 	unlockerr = lock_worktree(worktree, LOCK_SH);
6331 	if (unlockerr && err == NULL)
6332 		err = unlockerr;
6333 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
6334 		struct got_commitable *ct = pe->data;
6335 
6336 		free_commitable(ct);
6337 	}
6338 	got_pathlist_free(&commitable_paths, GOT_PATHLIST_FREE_NONE);
6339 	if (diff_path && unlink(diff_path) == -1 && err == NULL)
6340 		err = got_error_from_errno2("unlink", diff_path);
6341 	free(diff_path);
6342 	if (cc_arg.diff_outfile && fclose(cc_arg.diff_outfile) == EOF &&
6343 	    err == NULL)
6344 		err = got_error_from_errno("fclose");
6345 	return err;
6346 }
6347 
6348 const char *
6349 got_commitable_get_path(struct got_commitable *ct)
6350 {
6351 	return ct->path;
6352 }
6353 
6354 unsigned int
6355 got_commitable_get_status(struct got_commitable *ct)
6356 {
6357 	return ct->status;
6358 }
6359 
6360 struct check_rebase_ok_arg {
6361 	struct got_worktree *worktree;
6362 	struct got_repository *repo;
6363 };
6364 
6365 static const struct got_error *
6366 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
6367 {
6368 	const struct got_error *err = NULL;
6369 	struct check_rebase_ok_arg *a = arg;
6370 	unsigned char status;
6371 	struct stat sb;
6372 	char *ondisk_path;
6373 
6374 	/* Reject rebase of a work tree with mixed base commits. */
6375 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
6376 	    SHA1_DIGEST_LENGTH))
6377 		return got_error(GOT_ERR_MIXED_COMMITS);
6378 
6379 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
6380 	    == -1)
6381 		return got_error_from_errno("asprintf");
6382 
6383 	/* Reject rebase of a work tree with modified or staged files. */
6384 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
6385 	free(ondisk_path);
6386 	if (err)
6387 		return err;
6388 
6389 	if (status != GOT_STATUS_NO_CHANGE)
6390 		return got_error(GOT_ERR_MODIFIED);
6391 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
6392 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
6393 
6394 	return NULL;
6395 }
6396 
6397 const struct got_error *
6398 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
6399     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
6400     struct got_worktree *worktree, struct got_reference *branch,
6401     struct got_repository *repo)
6402 {
6403 	const struct got_error *err = NULL;
6404 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
6405 	char *branch_ref_name = NULL;
6406 	char *fileindex_path = NULL;
6407 	struct check_rebase_ok_arg ok_arg;
6408 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
6409 	struct got_object_id *wt_branch_tip = NULL;
6410 
6411 	*new_base_branch_ref = NULL;
6412 	*tmp_branch = NULL;
6413 	*fileindex = NULL;
6414 
6415 	err = lock_worktree(worktree, LOCK_EX);
6416 	if (err)
6417 		return err;
6418 
6419 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6420 	if (err)
6421 		goto done;
6422 
6423 	ok_arg.worktree = worktree;
6424 	ok_arg.repo = repo;
6425 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
6426 	    &ok_arg);
6427 	if (err)
6428 		goto done;
6429 
6430 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6431 	if (err)
6432 		goto done;
6433 
6434 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6435 	if (err)
6436 		goto done;
6437 
6438 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6439 	if (err)
6440 		goto done;
6441 
6442 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
6443 	    0);
6444 	if (err)
6445 		goto done;
6446 
6447 	err = got_ref_resolve(&wt_branch_tip, repo, wt_branch);
6448 	if (err)
6449 		goto done;
6450 	if (got_object_id_cmp(worktree->base_commit_id, wt_branch_tip) != 0) {
6451 		err = got_error(GOT_ERR_REBASE_OUT_OF_DATE);
6452 		goto done;
6453 	}
6454 
6455 	err = got_ref_alloc_symref(new_base_branch_ref,
6456 	    new_base_branch_ref_name, wt_branch);
6457 	if (err)
6458 		goto done;
6459 	err = got_ref_write(*new_base_branch_ref, repo);
6460 	if (err)
6461 		goto done;
6462 
6463 	/* TODO Lock original branch's ref while rebasing? */
6464 
6465 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
6466 	if (err)
6467 		goto done;
6468 
6469 	err = got_ref_write(branch_ref, repo);
6470 	if (err)
6471 		goto done;
6472 
6473 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
6474 	    worktree->base_commit_id);
6475 	if (err)
6476 		goto done;
6477 	err = got_ref_write(*tmp_branch, repo);
6478 	if (err)
6479 		goto done;
6480 
6481 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
6482 	if (err)
6483 		goto done;
6484 done:
6485 	free(fileindex_path);
6486 	free(tmp_branch_name);
6487 	free(new_base_branch_ref_name);
6488 	free(branch_ref_name);
6489 	if (branch_ref)
6490 		got_ref_close(branch_ref);
6491 	if (wt_branch)
6492 		got_ref_close(wt_branch);
6493 	free(wt_branch_tip);
6494 	if (err) {
6495 		if (*new_base_branch_ref) {
6496 			got_ref_close(*new_base_branch_ref);
6497 			*new_base_branch_ref = NULL;
6498 		}
6499 		if (*tmp_branch) {
6500 			got_ref_close(*tmp_branch);
6501 			*tmp_branch = NULL;
6502 		}
6503 		if (*fileindex) {
6504 			got_fileindex_free(*fileindex);
6505 			*fileindex = NULL;
6506 		}
6507 		lock_worktree(worktree, LOCK_SH);
6508 	}
6509 	return err;
6510 }
6511 
6512 const struct got_error *
6513 got_worktree_rebase_continue(struct got_object_id **commit_id,
6514     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
6515     struct got_reference **branch, struct got_fileindex **fileindex,
6516     struct got_worktree *worktree, struct got_repository *repo)
6517 {
6518 	const struct got_error *err;
6519 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
6520 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
6521 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
6522 	char *fileindex_path = NULL;
6523 	int have_staged_files = 0;
6524 
6525 	*commit_id = NULL;
6526 	*new_base_branch = NULL;
6527 	*tmp_branch = NULL;
6528 	*branch = NULL;
6529 	*fileindex = NULL;
6530 
6531 	err = lock_worktree(worktree, LOCK_EX);
6532 	if (err)
6533 		return err;
6534 
6535 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6536 	if (err)
6537 		goto done;
6538 
6539 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
6540 	    &have_staged_files);
6541 	if (err && err->code != GOT_ERR_CANCELLED)
6542 		goto done;
6543 	if (have_staged_files) {
6544 		err = got_error(GOT_ERR_STAGED_PATHS);
6545 		goto done;
6546 	}
6547 
6548 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6549 	if (err)
6550 		goto done;
6551 
6552 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6553 	if (err)
6554 		goto done;
6555 
6556 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6557 	if (err)
6558 		goto done;
6559 
6560 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6561 	if (err)
6562 		goto done;
6563 
6564 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
6565 	if (err)
6566 		goto done;
6567 
6568 	err = got_ref_open(branch, repo,
6569 	    got_ref_get_symref_target(branch_ref), 0);
6570 	if (err)
6571 		goto done;
6572 
6573 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6574 	if (err)
6575 		goto done;
6576 
6577 	err = got_ref_resolve(commit_id, repo, commit_ref);
6578 	if (err)
6579 		goto done;
6580 
6581 	err = got_ref_open(new_base_branch, repo,
6582 	    new_base_branch_ref_name, 0);
6583 	if (err)
6584 		goto done;
6585 
6586 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
6587 	if (err)
6588 		goto done;
6589 done:
6590 	free(commit_ref_name);
6591 	free(branch_ref_name);
6592 	free(fileindex_path);
6593 	if (commit_ref)
6594 		got_ref_close(commit_ref);
6595 	if (branch_ref)
6596 		got_ref_close(branch_ref);
6597 	if (err) {
6598 		free(*commit_id);
6599 		*commit_id = NULL;
6600 		if (*tmp_branch) {
6601 			got_ref_close(*tmp_branch);
6602 			*tmp_branch = NULL;
6603 		}
6604 		if (*new_base_branch) {
6605 			got_ref_close(*new_base_branch);
6606 			*new_base_branch = NULL;
6607 		}
6608 		if (*branch) {
6609 			got_ref_close(*branch);
6610 			*branch = NULL;
6611 		}
6612 		if (*fileindex) {
6613 			got_fileindex_free(*fileindex);
6614 			*fileindex = NULL;
6615 		}
6616 		lock_worktree(worktree, LOCK_SH);
6617 	}
6618 	return err;
6619 }
6620 
6621 const struct got_error *
6622 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
6623 {
6624 	const struct got_error *err;
6625 	char *tmp_branch_name = NULL;
6626 
6627 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6628 	if (err)
6629 		return err;
6630 
6631 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
6632 	free(tmp_branch_name);
6633 	return NULL;
6634 }
6635 
6636 static const struct got_error *
6637 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
6638     const char *diff_path, char **logmsg, void *arg)
6639 {
6640 	*logmsg = arg;
6641 	return NULL;
6642 }
6643 
6644 static const struct got_error *
6645 rebase_status(void *arg, unsigned char status, unsigned char staged_status,
6646     const char *path, struct got_object_id *blob_id,
6647     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
6648     int dirfd, const char *de_name)
6649 {
6650 	return NULL;
6651 }
6652 
6653 struct collect_merged_paths_arg {
6654 	got_worktree_checkout_cb progress_cb;
6655 	void *progress_arg;
6656 	struct got_pathlist_head *merged_paths;
6657 };
6658 
6659 static const struct got_error *
6660 collect_merged_paths(void *arg, unsigned char status, const char *path)
6661 {
6662 	const struct got_error *err;
6663 	struct collect_merged_paths_arg *a = arg;
6664 	char *p;
6665 	struct got_pathlist_entry *new;
6666 
6667 	err = (*a->progress_cb)(a->progress_arg, status, path);
6668 	if (err)
6669 		return err;
6670 
6671 	if (status != GOT_STATUS_MERGE &&
6672 	    status != GOT_STATUS_ADD &&
6673 	    status != GOT_STATUS_DELETE &&
6674 	    status != GOT_STATUS_CONFLICT)
6675 		return NULL;
6676 
6677 	p = strdup(path);
6678 	if (p == NULL)
6679 		return got_error_from_errno("strdup");
6680 
6681 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
6682 	if (err || new == NULL)
6683 		free(p);
6684 	return err;
6685 }
6686 
6687 static const struct got_error *
6688 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
6689     int is_rebase, struct got_repository *repo)
6690 {
6691 	const struct got_error *err;
6692 	struct got_reference *commit_ref = NULL;
6693 
6694 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6695 	if (err) {
6696 		if (err->code != GOT_ERR_NOT_REF)
6697 			goto done;
6698 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
6699 		if (err)
6700 			goto done;
6701 		err = got_ref_write(commit_ref, repo);
6702 		if (err)
6703 			goto done;
6704 	} else if (is_rebase) {
6705 		struct got_object_id *stored_id;
6706 		int cmp;
6707 
6708 		err = got_ref_resolve(&stored_id, repo, commit_ref);
6709 		if (err)
6710 			goto done;
6711 		cmp = got_object_id_cmp(commit_id, stored_id);
6712 		free(stored_id);
6713 		if (cmp != 0) {
6714 			err = got_error(GOT_ERR_REBASE_COMMITID);
6715 			goto done;
6716 		}
6717 	}
6718 done:
6719 	if (commit_ref)
6720 		got_ref_close(commit_ref);
6721 	return err;
6722 }
6723 
6724 static const struct got_error *
6725 rebase_merge_files(struct got_pathlist_head *merged_paths,
6726     const char *commit_ref_name, struct got_worktree *worktree,
6727     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
6728     struct got_object_id *commit_id, struct got_repository *repo,
6729     got_worktree_checkout_cb progress_cb, void *progress_arg,
6730     got_cancel_cb cancel_cb, void *cancel_arg)
6731 {
6732 	const struct got_error *err;
6733 	struct got_reference *commit_ref = NULL;
6734 	struct collect_merged_paths_arg cmp_arg;
6735 	char *fileindex_path;
6736 
6737 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6738 
6739 	err = get_fileindex_path(&fileindex_path, worktree);
6740 	if (err)
6741 		return err;
6742 
6743 	cmp_arg.progress_cb = progress_cb;
6744 	cmp_arg.progress_arg = progress_arg;
6745 	cmp_arg.merged_paths = merged_paths;
6746 	err = merge_files(worktree, fileindex, fileindex_path,
6747 	    parent_commit_id, commit_id, repo, collect_merged_paths,
6748 	    &cmp_arg, cancel_cb, cancel_arg);
6749 	if (commit_ref)
6750 		got_ref_close(commit_ref);
6751 	return err;
6752 }
6753 
6754 const struct got_error *
6755 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
6756     struct got_worktree *worktree, struct got_fileindex *fileindex,
6757     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6758     struct got_repository *repo,
6759     got_worktree_checkout_cb progress_cb, void *progress_arg,
6760     got_cancel_cb cancel_cb, void *cancel_arg)
6761 {
6762 	const struct got_error *err;
6763 	char *commit_ref_name;
6764 
6765 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6766 	if (err)
6767 		return err;
6768 
6769 	err = store_commit_id(commit_ref_name, commit_id, 1, repo);
6770 	if (err)
6771 		goto done;
6772 
6773 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6774 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6775 	    progress_arg, cancel_cb, cancel_arg);
6776 done:
6777 	free(commit_ref_name);
6778 	return err;
6779 }
6780 
6781 const struct got_error *
6782 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
6783     struct got_worktree *worktree, struct got_fileindex *fileindex,
6784     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6785     struct got_repository *repo,
6786     got_worktree_checkout_cb progress_cb, void *progress_arg,
6787     got_cancel_cb cancel_cb, void *cancel_arg)
6788 {
6789 	const struct got_error *err;
6790 	char *commit_ref_name;
6791 
6792 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6793 	if (err)
6794 		return err;
6795 
6796 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
6797 	if (err)
6798 		goto done;
6799 
6800 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6801 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6802 	    progress_arg, cancel_cb, cancel_arg);
6803 done:
6804 	free(commit_ref_name);
6805 	return err;
6806 }
6807 
6808 static const struct got_error *
6809 rebase_commit(struct got_object_id **new_commit_id,
6810     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
6811     struct got_worktree *worktree, struct got_fileindex *fileindex,
6812     struct got_reference *tmp_branch, const char *committer,
6813     struct got_commit_object *orig_commit, const char *new_logmsg,
6814     int allow_conflict, struct got_repository *repo)
6815 {
6816 	const struct got_error *err, *sync_err;
6817 	struct got_pathlist_head commitable_paths;
6818 	struct collect_commitables_arg cc_arg;
6819 	char *fileindex_path = NULL;
6820 	struct got_reference *head_ref = NULL;
6821 	struct got_object_id *head_commit_id = NULL;
6822 	char *logmsg = NULL;
6823 
6824 	memset(&cc_arg, 0, sizeof(cc_arg));
6825 	TAILQ_INIT(&commitable_paths);
6826 	*new_commit_id = NULL;
6827 
6828 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6829 
6830 	err = get_fileindex_path(&fileindex_path, worktree);
6831 	if (err)
6832 		return err;
6833 
6834 	cc_arg.commitable_paths = &commitable_paths;
6835 	cc_arg.worktree = worktree;
6836 	cc_arg.repo = repo;
6837 	cc_arg.have_staged_files = 0;
6838 	cc_arg.commit_conflicts = allow_conflict;
6839 	/*
6840 	 * If possible get the status of individual files directly to
6841 	 * avoid crawling the entire work tree once per rebased commit.
6842 	 *
6843 	 * Ideally, merged_paths would contain a list of commitables
6844 	 * we could use so we could skip worktree_status() entirely.
6845 	 * However, we would then need carefully keep track of cumulative
6846 	 * effects of operations such as file additions and deletions
6847 	 * in 'got histedit -f' (folding multiple commits into one),
6848 	 * and this extra complexity is not really worth it.
6849 	 */
6850 	if (merged_paths) {
6851 		struct got_pathlist_entry *pe;
6852 		TAILQ_FOREACH(pe, merged_paths, entry) {
6853 			err = worktree_status(worktree, pe->path, fileindex,
6854 			    repo, collect_commitables, &cc_arg, NULL, NULL, 1,
6855 			    0);
6856 			if (err)
6857 				goto done;
6858 		}
6859 	} else {
6860 		err = worktree_status(worktree, "", fileindex, repo,
6861 		    collect_commitables, &cc_arg, NULL, NULL, 1, 0);
6862 		if (err)
6863 			goto done;
6864 	}
6865 
6866 	if (TAILQ_EMPTY(&commitable_paths)) {
6867 		/* No-op change; commit will be elided. */
6868 		err = got_ref_delete(commit_ref, repo);
6869 		if (err)
6870 			goto done;
6871 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
6872 		goto done;
6873 	}
6874 
6875 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
6876 	if (err)
6877 		goto done;
6878 
6879 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
6880 	if (err)
6881 		goto done;
6882 
6883 	if (new_logmsg) {
6884 		logmsg = strdup(new_logmsg);
6885 		if (logmsg == NULL) {
6886 			err = got_error_from_errno("strdup");
6887 			goto done;
6888 		}
6889 	} else {
6890 		err = got_object_commit_get_logmsg(&logmsg, orig_commit);
6891 		if (err)
6892 			goto done;
6893 	}
6894 
6895 	/* NB: commit_worktree will call free(logmsg) */
6896 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
6897 	    NULL, worktree, got_object_commit_get_author(orig_commit),
6898 	    committer ? committer :
6899 	    got_object_commit_get_committer(orig_commit), NULL,
6900 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
6901 	if (err)
6902 		goto done;
6903 
6904 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
6905 	if (err)
6906 		goto done;
6907 
6908 	err = got_ref_delete(commit_ref, repo);
6909 	if (err)
6910 		goto done;
6911 
6912 	err = update_fileindex_after_commit(worktree, &commitable_paths,
6913 	    *new_commit_id, fileindex, 0);
6914 	sync_err = sync_fileindex(fileindex, fileindex_path);
6915 	if (sync_err && err == NULL)
6916 		err = sync_err;
6917 done:
6918 	free(fileindex_path);
6919 	free(head_commit_id);
6920 	if (head_ref)
6921 		got_ref_close(head_ref);
6922 	if (err) {
6923 		free(*new_commit_id);
6924 		*new_commit_id = NULL;
6925 	}
6926 	return err;
6927 }
6928 
6929 const struct got_error *
6930 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
6931     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6932     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6933     const char *committer, struct got_commit_object *orig_commit,
6934     struct got_object_id *orig_commit_id, int allow_conflict,
6935     struct got_repository *repo)
6936 {
6937 	const struct got_error *err;
6938 	char *commit_ref_name;
6939 	struct got_reference *commit_ref = NULL;
6940 	struct got_object_id *commit_id = NULL;
6941 
6942 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6943 	if (err)
6944 		return err;
6945 
6946 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6947 	if (err)
6948 		goto done;
6949 	err = got_ref_resolve(&commit_id, repo, commit_ref);
6950 	if (err)
6951 		goto done;
6952 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
6953 		err = got_error(GOT_ERR_REBASE_COMMITID);
6954 		goto done;
6955 	}
6956 
6957 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6958 	    worktree, fileindex, tmp_branch, committer, orig_commit,
6959 	    NULL, allow_conflict, repo);
6960 done:
6961 	if (commit_ref)
6962 		got_ref_close(commit_ref);
6963 	free(commit_ref_name);
6964 	free(commit_id);
6965 	return err;
6966 }
6967 
6968 const struct got_error *
6969 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
6970     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6971     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6972     const char *committer, struct got_commit_object *orig_commit,
6973     struct got_object_id *orig_commit_id, const char *new_logmsg,
6974     int allow_conflict, struct got_repository *repo)
6975 {
6976 	const struct got_error *err;
6977 	char *commit_ref_name;
6978 	struct got_reference *commit_ref = NULL;
6979 
6980 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6981 	if (err)
6982 		return err;
6983 
6984 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6985 	if (err)
6986 		goto done;
6987 
6988 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6989 	    worktree, fileindex, tmp_branch, committer, orig_commit,
6990 	    new_logmsg, allow_conflict, repo);
6991 done:
6992 	if (commit_ref)
6993 		got_ref_close(commit_ref);
6994 	free(commit_ref_name);
6995 	return err;
6996 }
6997 
6998 const struct got_error *
6999 got_worktree_rebase_postpone(struct got_worktree *worktree,
7000     struct got_fileindex *fileindex)
7001 {
7002 	if (fileindex)
7003 		got_fileindex_free(fileindex);
7004 	return lock_worktree(worktree, LOCK_SH);
7005 }
7006 
7007 static const struct got_error *
7008 delete_ref(const char *name, struct got_repository *repo)
7009 {
7010 	const struct got_error *err;
7011 	struct got_reference *ref;
7012 
7013 	err = got_ref_open(&ref, repo, name, 0);
7014 	if (err) {
7015 		if (err->code == GOT_ERR_NOT_REF)
7016 			return NULL;
7017 		return err;
7018 	}
7019 
7020 	err = got_ref_delete(ref, repo);
7021 	got_ref_close(ref);
7022 	return err;
7023 }
7024 
7025 static const struct got_error *
7026 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
7027 {
7028 	const struct got_error *err;
7029 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
7030 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
7031 
7032 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
7033 	if (err)
7034 		goto done;
7035 	err = delete_ref(tmp_branch_name, repo);
7036 	if (err)
7037 		goto done;
7038 
7039 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
7040 	if (err)
7041 		goto done;
7042 	err = delete_ref(new_base_branch_ref_name, repo);
7043 	if (err)
7044 		goto done;
7045 
7046 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
7047 	if (err)
7048 		goto done;
7049 	err = delete_ref(branch_ref_name, repo);
7050 	if (err)
7051 		goto done;
7052 
7053 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
7054 	if (err)
7055 		goto done;
7056 	err = delete_ref(commit_ref_name, repo);
7057 	if (err)
7058 		goto done;
7059 
7060 done:
7061 	free(tmp_branch_name);
7062 	free(new_base_branch_ref_name);
7063 	free(branch_ref_name);
7064 	free(commit_ref_name);
7065 	return err;
7066 }
7067 
7068 static const struct got_error *
7069 create_backup_ref(const char *backup_ref_prefix, struct got_reference *branch,
7070     struct got_object_id *new_commit_id, struct got_repository *repo)
7071 {
7072 	const struct got_error *err;
7073 	struct got_reference *ref = NULL;
7074 	struct got_object_id *old_commit_id = NULL;
7075 	const char *branch_name = NULL;
7076 	char *new_id_str = NULL;
7077 	char *refname = NULL;
7078 
7079 	branch_name = got_ref_get_name(branch);
7080 	if (strncmp(branch_name, "refs/heads/", 11) != 0)
7081 		return got_error(GOT_ERR_BAD_REF_NAME); /* should not happen */
7082 	branch_name += 11;
7083 
7084 	err = got_object_id_str(&new_id_str, new_commit_id);
7085 	if (err)
7086 		return err;
7087 
7088 	if (asprintf(&refname, "%s/%s/%s", backup_ref_prefix, branch_name,
7089 	    new_id_str) == -1) {
7090 		err = got_error_from_errno("asprintf");
7091 		goto done;
7092 	}
7093 
7094 	err = got_ref_resolve(&old_commit_id, repo, branch);
7095 	if (err)
7096 		goto done;
7097 
7098 	err = got_ref_alloc(&ref, refname, old_commit_id);
7099 	if (err)
7100 		goto done;
7101 
7102 	err = got_ref_write(ref, repo);
7103 done:
7104 	free(new_id_str);
7105 	free(refname);
7106 	free(old_commit_id);
7107 	if (ref)
7108 		got_ref_close(ref);
7109 	return err;
7110 }
7111 
7112 const struct got_error *
7113 got_worktree_rebase_complete(struct got_worktree *worktree,
7114     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
7115     struct got_reference *rebased_branch, struct got_repository *repo,
7116     int create_backup)
7117 {
7118 	const struct got_error *err, *unlockerr, *sync_err;
7119 	struct got_object_id *new_head_commit_id = NULL;
7120 	char *fileindex_path = NULL;
7121 
7122 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
7123 	if (err)
7124 		return err;
7125 
7126 	if (create_backup) {
7127 		err = create_backup_ref(GOT_WORKTREE_REBASE_BACKUP_REF_PREFIX,
7128 		    rebased_branch, new_head_commit_id, repo);
7129 		if (err)
7130 			goto done;
7131 	}
7132 
7133 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
7134 	if (err)
7135 		goto done;
7136 
7137 	err = got_ref_write(rebased_branch, repo);
7138 	if (err)
7139 		goto done;
7140 
7141 	err = got_worktree_set_head_ref(worktree, rebased_branch);
7142 	if (err)
7143 		goto done;
7144 
7145 	err = delete_rebase_refs(worktree, repo);
7146 	if (err)
7147 		goto done;
7148 
7149 	err = get_fileindex_path(&fileindex_path, worktree);
7150 	if (err)
7151 		goto done;
7152 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7153 	sync_err = sync_fileindex(fileindex, fileindex_path);
7154 	if (sync_err && err == NULL)
7155 		err = sync_err;
7156 done:
7157 	got_fileindex_free(fileindex);
7158 	free(fileindex_path);
7159 	free(new_head_commit_id);
7160 	unlockerr = lock_worktree(worktree, LOCK_SH);
7161 	if (unlockerr && err == NULL)
7162 		err = unlockerr;
7163 	return err;
7164 }
7165 
7166 const struct got_error *
7167 got_worktree_rebase_abort(struct got_worktree *worktree,
7168     struct got_fileindex *fileindex, struct got_repository *repo,
7169     struct got_reference *new_base_branch,
7170     got_worktree_checkout_cb progress_cb, void *progress_arg)
7171 {
7172 	const struct got_error *err, *unlockerr, *sync_err;
7173 	struct got_reference *resolved = NULL;
7174 	struct got_object_id *commit_id = NULL;
7175 	struct got_commit_object *commit = NULL;
7176 	char *fileindex_path = NULL;
7177 	struct revert_file_args rfa;
7178 	struct got_object_id *tree_id = NULL;
7179 
7180 	err = lock_worktree(worktree, LOCK_EX);
7181 	if (err)
7182 		return err;
7183 
7184 	err = got_object_open_as_commit(&commit, repo,
7185 	    worktree->base_commit_id);
7186 	if (err)
7187 		goto done;
7188 
7189 	err = got_ref_open(&resolved, repo,
7190 	    got_ref_get_symref_target(new_base_branch), 0);
7191 	if (err)
7192 		goto done;
7193 
7194 	err = got_worktree_set_head_ref(worktree, resolved);
7195 	if (err)
7196 		goto done;
7197 
7198 	/*
7199 	 * XXX commits to the base branch could have happened while
7200 	 * we were busy rebasing; should we store the original commit ID
7201 	 * when rebase begins and read it back here?
7202 	 */
7203 	err = got_ref_resolve(&commit_id, repo, resolved);
7204 	if (err)
7205 		goto done;
7206 
7207 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
7208 	if (err)
7209 		goto done;
7210 
7211 	err = got_object_id_by_path(&tree_id, repo, commit,
7212 	    worktree->path_prefix);
7213 	if (err)
7214 		goto done;
7215 
7216 	err = delete_rebase_refs(worktree, repo);
7217 	if (err)
7218 		goto done;
7219 
7220 	err = get_fileindex_path(&fileindex_path, worktree);
7221 	if (err)
7222 		goto done;
7223 
7224 	rfa.worktree = worktree;
7225 	rfa.fileindex = fileindex;
7226 	rfa.progress_cb = progress_cb;
7227 	rfa.progress_arg = progress_arg;
7228 	rfa.patch_cb = NULL;
7229 	rfa.patch_arg = NULL;
7230 	rfa.repo = repo;
7231 	rfa.unlink_added_files = 0;
7232 	err = worktree_status(worktree, "", fileindex, repo,
7233 	    revert_file, &rfa, NULL, NULL, 1, 0);
7234 	if (err)
7235 		goto sync;
7236 
7237 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
7238 	    repo, progress_cb, progress_arg, NULL, NULL);
7239 sync:
7240 	sync_err = sync_fileindex(fileindex, fileindex_path);
7241 	if (sync_err && err == NULL)
7242 		err = sync_err;
7243 done:
7244 	got_ref_close(resolved);
7245 	free(tree_id);
7246 	free(commit_id);
7247 	if (commit)
7248 		got_object_commit_close(commit);
7249 	if (fileindex)
7250 		got_fileindex_free(fileindex);
7251 	free(fileindex_path);
7252 
7253 	unlockerr = lock_worktree(worktree, LOCK_SH);
7254 	if (unlockerr && err == NULL)
7255 		err = unlockerr;
7256 	return err;
7257 }
7258 
7259 const struct got_error *
7260 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
7261     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
7262     struct got_fileindex **fileindex, struct got_worktree *worktree,
7263     struct got_repository *repo)
7264 {
7265 	const struct got_error *err = NULL;
7266 	char *tmp_branch_name = NULL;
7267 	char *branch_ref_name = NULL;
7268 	char *base_commit_ref_name = NULL;
7269 	char *fileindex_path = NULL;
7270 	struct check_rebase_ok_arg ok_arg;
7271 	struct got_reference *wt_branch = NULL;
7272 	struct got_reference *base_commit_ref = NULL;
7273 
7274 	*tmp_branch = NULL;
7275 	*branch_ref = NULL;
7276 	*base_commit_id = NULL;
7277 	*fileindex = NULL;
7278 
7279 	err = lock_worktree(worktree, LOCK_EX);
7280 	if (err)
7281 		return err;
7282 
7283 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7284 	if (err)
7285 		goto done;
7286 
7287 	ok_arg.worktree = worktree;
7288 	ok_arg.repo = repo;
7289 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
7290 	    &ok_arg);
7291 	if (err)
7292 		goto done;
7293 
7294 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7295 	if (err)
7296 		goto done;
7297 
7298 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7299 	if (err)
7300 		goto done;
7301 
7302 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7303 	    worktree);
7304 	if (err)
7305 		goto done;
7306 
7307 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
7308 	    0);
7309 	if (err)
7310 		goto done;
7311 
7312 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
7313 	if (err)
7314 		goto done;
7315 
7316 	err = got_ref_write(*branch_ref, repo);
7317 	if (err)
7318 		goto done;
7319 
7320 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
7321 	    worktree->base_commit_id);
7322 	if (err)
7323 		goto done;
7324 	err = got_ref_write(base_commit_ref, repo);
7325 	if (err)
7326 		goto done;
7327 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
7328 	if (*base_commit_id == NULL) {
7329 		err = got_error_from_errno("got_object_id_dup");
7330 		goto done;
7331 	}
7332 
7333 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
7334 	    worktree->base_commit_id);
7335 	if (err)
7336 		goto done;
7337 	err = got_ref_write(*tmp_branch, repo);
7338 	if (err)
7339 		goto done;
7340 
7341 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
7342 	if (err)
7343 		goto done;
7344 done:
7345 	free(fileindex_path);
7346 	free(tmp_branch_name);
7347 	free(branch_ref_name);
7348 	free(base_commit_ref_name);
7349 	if (wt_branch)
7350 		got_ref_close(wt_branch);
7351 	if (err) {
7352 		if (*branch_ref) {
7353 			got_ref_close(*branch_ref);
7354 			*branch_ref = NULL;
7355 		}
7356 		if (*tmp_branch) {
7357 			got_ref_close(*tmp_branch);
7358 			*tmp_branch = NULL;
7359 		}
7360 		free(*base_commit_id);
7361 		if (*fileindex) {
7362 			got_fileindex_free(*fileindex);
7363 			*fileindex = NULL;
7364 		}
7365 		lock_worktree(worktree, LOCK_SH);
7366 	}
7367 	return err;
7368 }
7369 
7370 const struct got_error *
7371 got_worktree_histedit_postpone(struct got_worktree *worktree,
7372     struct got_fileindex *fileindex)
7373 {
7374 	if (fileindex)
7375 		got_fileindex_free(fileindex);
7376 	return lock_worktree(worktree, LOCK_SH);
7377 }
7378 
7379 const struct got_error *
7380 got_worktree_histedit_in_progress(int *in_progress,
7381     struct got_worktree *worktree)
7382 {
7383 	const struct got_error *err;
7384 	char *tmp_branch_name = NULL;
7385 
7386 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7387 	if (err)
7388 		return err;
7389 
7390 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
7391 	free(tmp_branch_name);
7392 	return NULL;
7393 }
7394 
7395 const struct got_error *
7396 got_worktree_histedit_continue(struct got_object_id **commit_id,
7397     struct got_reference **tmp_branch, struct got_reference **branch_ref,
7398     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
7399     struct got_worktree *worktree, struct got_repository *repo)
7400 {
7401 	const struct got_error *err;
7402 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
7403 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
7404 	struct got_reference *commit_ref = NULL;
7405 	struct got_reference *base_commit_ref = NULL;
7406 	char *fileindex_path = NULL;
7407 	int have_staged_files = 0;
7408 
7409 	*commit_id = NULL;
7410 	*tmp_branch = NULL;
7411 	*base_commit_id = NULL;
7412 	*fileindex = NULL;
7413 
7414 	err = lock_worktree(worktree, LOCK_EX);
7415 	if (err)
7416 		return err;
7417 
7418 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7419 	if (err)
7420 		goto done;
7421 
7422 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
7423 	    &have_staged_files);
7424 	if (err && err->code != GOT_ERR_CANCELLED)
7425 		goto done;
7426 	if (have_staged_files) {
7427 		err = got_error(GOT_ERR_STAGED_PATHS);
7428 		goto done;
7429 	}
7430 
7431 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7432 	if (err)
7433 		goto done;
7434 
7435 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7436 	if (err)
7437 		goto done;
7438 
7439 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7440 	if (err)
7441 		goto done;
7442 
7443 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7444 	    worktree);
7445 	if (err)
7446 		goto done;
7447 
7448 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
7449 	if (err)
7450 		goto done;
7451 
7452 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
7453 	if (err)
7454 		goto done;
7455 	err = got_ref_resolve(commit_id, repo, commit_ref);
7456 	if (err)
7457 		goto done;
7458 
7459 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
7460 	if (err)
7461 		goto done;
7462 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
7463 	if (err)
7464 		goto done;
7465 
7466 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
7467 	if (err)
7468 		goto done;
7469 done:
7470 	free(commit_ref_name);
7471 	free(branch_ref_name);
7472 	free(fileindex_path);
7473 	if (commit_ref)
7474 		got_ref_close(commit_ref);
7475 	if (base_commit_ref)
7476 		got_ref_close(base_commit_ref);
7477 	if (err) {
7478 		free(*commit_id);
7479 		*commit_id = NULL;
7480 		free(*base_commit_id);
7481 		*base_commit_id = NULL;
7482 		if (*tmp_branch) {
7483 			got_ref_close(*tmp_branch);
7484 			*tmp_branch = NULL;
7485 		}
7486 		if (*fileindex) {
7487 			got_fileindex_free(*fileindex);
7488 			*fileindex = NULL;
7489 		}
7490 		lock_worktree(worktree, LOCK_EX);
7491 	}
7492 	return err;
7493 }
7494 
7495 static const struct got_error *
7496 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
7497 {
7498 	const struct got_error *err;
7499 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
7500 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
7501 
7502 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7503 	if (err)
7504 		goto done;
7505 	err = delete_ref(tmp_branch_name, repo);
7506 	if (err)
7507 		goto done;
7508 
7509 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7510 	    worktree);
7511 	if (err)
7512 		goto done;
7513 	err = delete_ref(base_commit_ref_name, repo);
7514 	if (err)
7515 		goto done;
7516 
7517 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7518 	if (err)
7519 		goto done;
7520 	err = delete_ref(branch_ref_name, repo);
7521 	if (err)
7522 		goto done;
7523 
7524 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7525 	if (err)
7526 		goto done;
7527 	err = delete_ref(commit_ref_name, repo);
7528 	if (err)
7529 		goto done;
7530 done:
7531 	free(tmp_branch_name);
7532 	free(base_commit_ref_name);
7533 	free(branch_ref_name);
7534 	free(commit_ref_name);
7535 	return err;
7536 }
7537 
7538 const struct got_error *
7539 got_worktree_histedit_abort(struct got_worktree *worktree,
7540     struct got_fileindex *fileindex, struct got_repository *repo,
7541     struct got_reference *branch, struct got_object_id *base_commit_id,
7542     got_worktree_checkout_cb progress_cb, void *progress_arg)
7543 {
7544 	const struct got_error *err, *unlockerr, *sync_err;
7545 	struct got_reference *resolved = NULL;
7546 	char *fileindex_path = NULL;
7547 	struct got_commit_object *commit = NULL;
7548 	struct got_object_id *tree_id = NULL;
7549 	struct revert_file_args rfa;
7550 
7551 	err = lock_worktree(worktree, LOCK_EX);
7552 	if (err)
7553 		return err;
7554 
7555 	err = got_object_open_as_commit(&commit, repo,
7556 	    worktree->base_commit_id);
7557 	if (err)
7558 		goto done;
7559 
7560 	err = got_ref_open(&resolved, repo,
7561 	    got_ref_get_symref_target(branch), 0);
7562 	if (err)
7563 		goto done;
7564 
7565 	err = got_worktree_set_head_ref(worktree, resolved);
7566 	if (err)
7567 		goto done;
7568 
7569 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
7570 	if (err)
7571 		goto done;
7572 
7573 	err = got_object_id_by_path(&tree_id, repo, commit,
7574 	    worktree->path_prefix);
7575 	if (err)
7576 		goto done;
7577 
7578 	err = delete_histedit_refs(worktree, repo);
7579 	if (err)
7580 		goto done;
7581 
7582 	err = get_fileindex_path(&fileindex_path, worktree);
7583 	if (err)
7584 		goto done;
7585 
7586 	rfa.worktree = worktree;
7587 	rfa.fileindex = fileindex;
7588 	rfa.progress_cb = progress_cb;
7589 	rfa.progress_arg = progress_arg;
7590 	rfa.patch_cb = NULL;
7591 	rfa.patch_arg = NULL;
7592 	rfa.repo = repo;
7593 	rfa.unlink_added_files = 0;
7594 	err = worktree_status(worktree, "", fileindex, repo,
7595 	    revert_file, &rfa, NULL, NULL, 1, 0);
7596 	if (err)
7597 		goto sync;
7598 
7599 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
7600 	    repo, progress_cb, progress_arg, NULL, NULL);
7601 sync:
7602 	sync_err = sync_fileindex(fileindex, fileindex_path);
7603 	if (sync_err && err == NULL)
7604 		err = sync_err;
7605 done:
7606 	got_ref_close(resolved);
7607 	free(tree_id);
7608 	free(fileindex_path);
7609 
7610 	unlockerr = lock_worktree(worktree, LOCK_SH);
7611 	if (unlockerr && err == NULL)
7612 		err = unlockerr;
7613 	return err;
7614 }
7615 
7616 const struct got_error *
7617 got_worktree_histedit_complete(struct got_worktree *worktree,
7618     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
7619     struct got_reference *edited_branch, struct got_repository *repo)
7620 {
7621 	const struct got_error *err, *unlockerr, *sync_err;
7622 	struct got_object_id *new_head_commit_id = NULL;
7623 	struct got_reference *resolved = NULL;
7624 	char *fileindex_path = NULL;
7625 
7626 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
7627 	if (err)
7628 		return err;
7629 
7630 	err = got_ref_open(&resolved, repo,
7631 	    got_ref_get_symref_target(edited_branch), 0);
7632 	if (err)
7633 		goto done;
7634 
7635 	err = create_backup_ref(GOT_WORKTREE_HISTEDIT_BACKUP_REF_PREFIX,
7636 	    resolved, new_head_commit_id, repo);
7637 	if (err)
7638 		goto done;
7639 
7640 	err = got_ref_change_ref(resolved, new_head_commit_id);
7641 	if (err)
7642 		goto done;
7643 
7644 	err = got_ref_write(resolved, repo);
7645 	if (err)
7646 		goto done;
7647 
7648 	err = got_worktree_set_head_ref(worktree, resolved);
7649 	if (err)
7650 		goto done;
7651 
7652 	err = delete_histedit_refs(worktree, repo);
7653 	if (err)
7654 		goto done;
7655 
7656 	err = get_fileindex_path(&fileindex_path, worktree);
7657 	if (err)
7658 		goto done;
7659 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7660 	sync_err = sync_fileindex(fileindex, fileindex_path);
7661 	if (sync_err && err == NULL)
7662 		err = sync_err;
7663 done:
7664 	got_fileindex_free(fileindex);
7665 	free(fileindex_path);
7666 	free(new_head_commit_id);
7667 	unlockerr = lock_worktree(worktree, LOCK_SH);
7668 	if (unlockerr && err == NULL)
7669 		err = unlockerr;
7670 	return err;
7671 }
7672 
7673 const struct got_error *
7674 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
7675     struct got_object_id *commit_id, struct got_repository *repo)
7676 {
7677 	const struct got_error *err;
7678 	char *commit_ref_name;
7679 
7680 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7681 	if (err)
7682 		return err;
7683 
7684 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
7685 	if (err)
7686 		goto done;
7687 
7688 	err = delete_ref(commit_ref_name, repo);
7689 done:
7690 	free(commit_ref_name);
7691 	return err;
7692 }
7693 
7694 const struct got_error *
7695 got_worktree_integrate_prepare(struct got_fileindex **fileindex,
7696     struct got_reference **branch_ref, struct got_reference **base_branch_ref,
7697     struct got_worktree *worktree, const char *refname,
7698     struct got_repository *repo)
7699 {
7700 	const struct got_error *err = NULL;
7701 	char *fileindex_path = NULL;
7702 	struct check_rebase_ok_arg ok_arg;
7703 
7704 	*fileindex = NULL;
7705 	*branch_ref = NULL;
7706 	*base_branch_ref = NULL;
7707 
7708 	err = lock_worktree(worktree, LOCK_EX);
7709 	if (err)
7710 		return err;
7711 
7712 	if (strcmp(refname, got_worktree_get_head_ref_name(worktree)) == 0) {
7713 		err = got_error_msg(GOT_ERR_SAME_BRANCH,
7714 		    "cannot integrate a branch into itself; "
7715 		    "update -b or different branch name required");
7716 		goto done;
7717 	}
7718 
7719 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7720 	if (err)
7721 		goto done;
7722 
7723 	/* Preconditions are the same as for rebase. */
7724 	ok_arg.worktree = worktree;
7725 	ok_arg.repo = repo;
7726 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
7727 	    &ok_arg);
7728 	if (err)
7729 		goto done;
7730 
7731 	err = got_ref_open(branch_ref, repo, refname, 1);
7732 	if (err)
7733 		goto done;
7734 
7735 	err = got_ref_open(base_branch_ref, repo,
7736 	    got_worktree_get_head_ref_name(worktree), 1);
7737 done:
7738 	if (err) {
7739 		if (*branch_ref) {
7740 			got_ref_close(*branch_ref);
7741 			*branch_ref = NULL;
7742 		}
7743 		if (*base_branch_ref) {
7744 			got_ref_close(*base_branch_ref);
7745 			*base_branch_ref = NULL;
7746 		}
7747 		if (*fileindex) {
7748 			got_fileindex_free(*fileindex);
7749 			*fileindex = NULL;
7750 		}
7751 		lock_worktree(worktree, LOCK_SH);
7752 	}
7753 	return err;
7754 }
7755 
7756 const struct got_error *
7757 got_worktree_integrate_continue(struct got_worktree *worktree,
7758     struct got_fileindex *fileindex, struct got_repository *repo,
7759     struct got_reference *branch_ref, struct got_reference *base_branch_ref,
7760     got_worktree_checkout_cb progress_cb, void *progress_arg,
7761     got_cancel_cb cancel_cb, void *cancel_arg)
7762 {
7763 	const struct got_error *err = NULL, *sync_err, *unlockerr;
7764 	char *fileindex_path = NULL;
7765 	struct got_object_id *tree_id = NULL, *commit_id = NULL;
7766 	struct got_commit_object *commit =  NULL;
7767 
7768 	err = get_fileindex_path(&fileindex_path, worktree);
7769 	if (err)
7770 		goto done;
7771 
7772 	err = got_ref_resolve(&commit_id, repo, branch_ref);
7773 	if (err)
7774 		goto done;
7775 
7776 	err = got_object_open_as_commit(&commit, repo, commit_id);
7777 	if (err)
7778 		goto done;
7779 
7780 	err = got_object_id_by_path(&tree_id, repo, commit,
7781 	    worktree->path_prefix);
7782 	if (err)
7783 		goto done;
7784 
7785 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
7786 	if (err)
7787 		goto done;
7788 
7789 	err = checkout_files(worktree, fileindex, "", tree_id, NULL, repo,
7790 	    progress_cb, progress_arg, cancel_cb, cancel_arg);
7791 	if (err)
7792 		goto sync;
7793 
7794 	err = got_ref_change_ref(base_branch_ref, commit_id);
7795 	if (err)
7796 		goto sync;
7797 
7798 	err = got_ref_write(base_branch_ref, repo);
7799 	if (err)
7800 		goto sync;
7801 
7802 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7803 sync:
7804 	sync_err = sync_fileindex(fileindex, fileindex_path);
7805 	if (sync_err && err == NULL)
7806 		err = sync_err;
7807 
7808 done:
7809 	unlockerr = got_ref_unlock(branch_ref);
7810 	if (unlockerr && err == NULL)
7811 		err = unlockerr;
7812 	got_ref_close(branch_ref);
7813 
7814 	unlockerr = got_ref_unlock(base_branch_ref);
7815 	if (unlockerr && err == NULL)
7816 		err = unlockerr;
7817 	got_ref_close(base_branch_ref);
7818 
7819 	got_fileindex_free(fileindex);
7820 	free(fileindex_path);
7821 	free(tree_id);
7822 	if (commit)
7823 		got_object_commit_close(commit);
7824 
7825 	unlockerr = lock_worktree(worktree, LOCK_SH);
7826 	if (unlockerr && err == NULL)
7827 		err = unlockerr;
7828 	return err;
7829 }
7830 
7831 const struct got_error *
7832 got_worktree_integrate_abort(struct got_worktree *worktree,
7833     struct got_fileindex *fileindex, struct got_repository *repo,
7834     struct got_reference *branch_ref, struct got_reference *base_branch_ref)
7835 {
7836 	const struct got_error *err = NULL, *unlockerr = NULL;
7837 
7838 	got_fileindex_free(fileindex);
7839 
7840 	err = lock_worktree(worktree, LOCK_SH);
7841 
7842 	unlockerr = got_ref_unlock(branch_ref);
7843 	if (unlockerr && err == NULL)
7844 		err = unlockerr;
7845 	got_ref_close(branch_ref);
7846 
7847 	unlockerr = got_ref_unlock(base_branch_ref);
7848 	if (unlockerr && err == NULL)
7849 		err = unlockerr;
7850 	got_ref_close(base_branch_ref);
7851 
7852 	return err;
7853 }
7854 
7855 const struct got_error *
7856 got_worktree_merge_postpone(struct got_worktree *worktree,
7857     struct got_fileindex *fileindex)
7858 {
7859 	const struct got_error *err, *sync_err;
7860 	char *fileindex_path = NULL;
7861 
7862 	err = get_fileindex_path(&fileindex_path, worktree);
7863 	if (err)
7864 		goto done;
7865 
7866 	sync_err = sync_fileindex(fileindex, fileindex_path);
7867 
7868 	err = lock_worktree(worktree, LOCK_SH);
7869 	if (sync_err && err == NULL)
7870 		err = sync_err;
7871 done:
7872 	got_fileindex_free(fileindex);
7873 	free(fileindex_path);
7874 	return err;
7875 }
7876 
7877 static const struct got_error *
7878 delete_merge_refs(struct got_worktree *worktree, struct got_repository *repo)
7879 {
7880 	const struct got_error *err;
7881 	char *branch_refname = NULL, *commit_refname = NULL;
7882 
7883 	err = get_merge_branch_ref_name(&branch_refname, worktree);
7884 	if (err)
7885 		goto done;
7886 	err = delete_ref(branch_refname, repo);
7887 	if (err)
7888 		goto done;
7889 
7890 	err = get_merge_commit_ref_name(&commit_refname, worktree);
7891 	if (err)
7892 		goto done;
7893 	err = delete_ref(commit_refname, repo);
7894 	if (err)
7895 		goto done;
7896 
7897 done:
7898 	free(branch_refname);
7899 	free(commit_refname);
7900 	return err;
7901 }
7902 
7903 struct merge_commit_msg_arg {
7904 	struct got_worktree *worktree;
7905 	const char *branch_name;
7906 };
7907 
7908 static const struct got_error *
7909 merge_commit_msg_cb(struct got_pathlist_head *commitable_paths,
7910     const char *diff_path, char **logmsg, void *arg)
7911 {
7912 	struct merge_commit_msg_arg *a = arg;
7913 
7914 	if (asprintf(logmsg, "merge %s into %s\n", a->branch_name,
7915 	    got_worktree_get_head_ref_name(a->worktree)) == -1)
7916 		return got_error_from_errno("asprintf");
7917 
7918 	return NULL;
7919 }
7920 
7921 
7922 const struct got_error *
7923 got_worktree_merge_branch(struct got_worktree *worktree,
7924     struct got_fileindex *fileindex,
7925     struct got_object_id *yca_commit_id,
7926     struct got_object_id *branch_tip,
7927     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
7928     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
7929 {
7930 	const struct got_error *err;
7931 	char *fileindex_path = NULL;
7932 
7933 	err = get_fileindex_path(&fileindex_path, worktree);
7934 	if (err)
7935 		goto done;
7936 
7937 	err = got_fileindex_for_each_entry_safe(fileindex, check_mixed_commits,
7938 	    worktree);
7939 	if (err)
7940 		goto done;
7941 
7942 	err = merge_files(worktree, fileindex, fileindex_path, yca_commit_id,
7943 	    branch_tip, repo, progress_cb, progress_arg,
7944 	    cancel_cb, cancel_arg);
7945 done:
7946 	free(fileindex_path);
7947 	return err;
7948 }
7949 
7950 const struct got_error *
7951 got_worktree_merge_commit(struct got_object_id **new_commit_id,
7952     struct got_worktree *worktree, struct got_fileindex *fileindex,
7953     const char *author, const char *committer, int allow_bad_symlinks,
7954     struct got_object_id *branch_tip, const char *branch_name,
7955     int allow_conflict, struct got_repository *repo,
7956     got_worktree_status_cb status_cb, void *status_arg)
7957 
7958 {
7959 	const struct got_error *err = NULL, *sync_err;
7960 	struct got_pathlist_head commitable_paths;
7961 	struct collect_commitables_arg cc_arg;
7962 	struct got_pathlist_entry *pe;
7963 	struct got_reference *head_ref = NULL;
7964 	struct got_object_id *head_commit_id = NULL;
7965 	int have_staged_files = 0;
7966 	struct merge_commit_msg_arg mcm_arg;
7967 	char *fileindex_path = NULL;
7968 
7969 	memset(&cc_arg, 0, sizeof(cc_arg));
7970 	*new_commit_id = NULL;
7971 
7972 	TAILQ_INIT(&commitable_paths);
7973 
7974 	err = get_fileindex_path(&fileindex_path, worktree);
7975 	if (err)
7976 		goto done;
7977 
7978 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
7979 	if (err)
7980 		goto done;
7981 
7982 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
7983 	if (err)
7984 		goto done;
7985 
7986 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
7987 	    &have_staged_files);
7988 	if (err && err->code != GOT_ERR_CANCELLED)
7989 		goto done;
7990 	if (have_staged_files) {
7991 		err = got_error(GOT_ERR_MERGE_STAGED_PATHS);
7992 		goto done;
7993 	}
7994 
7995 	cc_arg.commitable_paths = &commitable_paths;
7996 	cc_arg.worktree = worktree;
7997 	cc_arg.fileindex = fileindex;
7998 	cc_arg.repo = repo;
7999 	cc_arg.have_staged_files = have_staged_files;
8000 	cc_arg.allow_bad_symlinks = allow_bad_symlinks;
8001 	cc_arg.commit_conflicts = allow_conflict;
8002 	err = worktree_status(worktree, "", fileindex, repo,
8003 	    collect_commitables, &cc_arg, NULL, NULL, 1, 0);
8004 	if (err)
8005 		goto done;
8006 
8007 	if (TAILQ_EMPTY(&commitable_paths)) {
8008 		err = got_error_fmt(GOT_ERR_COMMIT_NO_CHANGES,
8009 		    "merge of %s cannot proceed", branch_name);
8010 		goto done;
8011 	}
8012 
8013 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
8014 		struct got_commitable *ct = pe->data;
8015 		const char *ct_path = ct->in_repo_path;
8016 
8017 		while (ct_path[0] == '/')
8018 			ct_path++;
8019 		err = check_out_of_date(ct_path, ct->status,
8020 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
8021 		    head_commit_id, repo, GOT_ERR_MERGE_COMMIT_OUT_OF_DATE);
8022 		if (err)
8023 			goto done;
8024 
8025 	}
8026 
8027 	mcm_arg.worktree = worktree;
8028 	mcm_arg.branch_name = branch_name;
8029 	err = commit_worktree(new_commit_id, &commitable_paths,
8030 	    head_commit_id, branch_tip, worktree, author, committer, NULL,
8031 	    merge_commit_msg_cb, &mcm_arg, status_cb, status_arg, repo);
8032 	if (err)
8033 		goto done;
8034 
8035 	err = update_fileindex_after_commit(worktree, &commitable_paths,
8036 	    *new_commit_id, fileindex, have_staged_files);
8037 	sync_err = sync_fileindex(fileindex, fileindex_path);
8038 	if (sync_err && err == NULL)
8039 		err = sync_err;
8040 done:
8041 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
8042 		struct got_commitable *ct = pe->data;
8043 
8044 		free_commitable(ct);
8045 	}
8046 	got_pathlist_free(&commitable_paths, GOT_PATHLIST_FREE_NONE);
8047 	free(fileindex_path);
8048 	return err;
8049 }
8050 
8051 const struct got_error *
8052 got_worktree_merge_complete(struct got_worktree *worktree,
8053     struct got_fileindex *fileindex, struct got_repository *repo)
8054 {
8055 	const struct got_error *err, *unlockerr, *sync_err;
8056 	char *fileindex_path = NULL;
8057 
8058 	err = delete_merge_refs(worktree, repo);
8059 	if (err)
8060 		goto done;
8061 
8062 	err = get_fileindex_path(&fileindex_path, worktree);
8063 	if (err)
8064 		goto done;
8065 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
8066 	sync_err = sync_fileindex(fileindex, fileindex_path);
8067 	if (sync_err && err == NULL)
8068 		err = sync_err;
8069 done:
8070 	got_fileindex_free(fileindex);
8071 	free(fileindex_path);
8072 	unlockerr = lock_worktree(worktree, LOCK_SH);
8073 	if (unlockerr && err == NULL)
8074 		err = unlockerr;
8075 	return err;
8076 }
8077 
8078 const struct got_error *
8079 got_worktree_merge_in_progress(int *in_progress, struct got_worktree *worktree,
8080     struct got_repository *repo)
8081 {
8082 	const struct got_error *err;
8083 	char *branch_refname = NULL;
8084 	struct got_reference *branch_ref = NULL;
8085 
8086 	*in_progress = 0;
8087 
8088 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8089 	if (err)
8090 		return err;
8091 	err = got_ref_open(&branch_ref, repo, branch_refname, 0);
8092 	free(branch_refname);
8093 	if (err) {
8094 		if (err->code != GOT_ERR_NOT_REF)
8095 			return err;
8096 	} else
8097 		*in_progress = 1;
8098 
8099 	return NULL;
8100 }
8101 
8102 const struct got_error *got_worktree_merge_prepare(
8103     struct got_fileindex **fileindex, struct got_worktree *worktree,
8104     struct got_reference *branch, struct got_repository *repo)
8105 {
8106 	const struct got_error *err = NULL;
8107 	char *fileindex_path = NULL;
8108 	char *branch_refname = NULL, *commit_refname = NULL;
8109 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
8110 	struct got_reference *commit_ref = NULL;
8111 	struct got_object_id *branch_tip = NULL, *wt_branch_tip = NULL;
8112 	struct check_rebase_ok_arg ok_arg;
8113 
8114 	*fileindex = NULL;
8115 
8116 	err = lock_worktree(worktree, LOCK_EX);
8117 	if (err)
8118 		return err;
8119 
8120 	err = open_fileindex(fileindex, &fileindex_path, worktree);
8121 	if (err)
8122 		goto done;
8123 
8124 	/* Preconditions are the same as for rebase. */
8125 	ok_arg.worktree = worktree;
8126 	ok_arg.repo = repo;
8127 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
8128 	    &ok_arg);
8129 	if (err)
8130 		goto done;
8131 
8132 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8133 	if (err)
8134 		return err;
8135 
8136 	err = get_merge_commit_ref_name(&commit_refname, worktree);
8137 	if (err)
8138 		return err;
8139 
8140 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
8141 	    0);
8142 	if (err)
8143 		goto done;
8144 
8145 	err = got_ref_resolve(&wt_branch_tip, repo, wt_branch);
8146 	if (err)
8147 		goto done;
8148 
8149 	if (got_object_id_cmp(worktree->base_commit_id, wt_branch_tip) != 0) {
8150 		err = got_error(GOT_ERR_MERGE_OUT_OF_DATE);
8151 		goto done;
8152 	}
8153 
8154 	err = got_ref_resolve(&branch_tip, repo, branch);
8155 	if (err)
8156 		goto done;
8157 
8158 	err = got_ref_alloc_symref(&branch_ref, branch_refname, branch);
8159 	if (err)
8160 		goto done;
8161 	err = got_ref_write(branch_ref, repo);
8162 	if (err)
8163 		goto done;
8164 
8165 	err = got_ref_alloc(&commit_ref, commit_refname, branch_tip);
8166 	if (err)
8167 		goto done;
8168 	err = got_ref_write(commit_ref, repo);
8169 	if (err)
8170 		goto done;
8171 
8172 done:
8173 	free(branch_refname);
8174 	free(commit_refname);
8175 	free(fileindex_path);
8176 	if (branch_ref)
8177 		got_ref_close(branch_ref);
8178 	if (commit_ref)
8179 		got_ref_close(commit_ref);
8180 	if (wt_branch)
8181 		got_ref_close(wt_branch);
8182 	free(wt_branch_tip);
8183 	if (err) {
8184 		if (*fileindex) {
8185 			got_fileindex_free(*fileindex);
8186 			*fileindex = NULL;
8187 		}
8188 		lock_worktree(worktree, LOCK_SH);
8189 	}
8190 	return err;
8191 }
8192 
8193 const struct got_error *
8194 got_worktree_merge_continue(char **branch_name,
8195     struct got_object_id **branch_tip, struct got_fileindex **fileindex,
8196     struct got_worktree *worktree, struct got_repository *repo)
8197 {
8198 	const struct got_error *err;
8199 	char *commit_refname = NULL, *branch_refname = NULL;
8200 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
8201 	char *fileindex_path = NULL;
8202 	int have_staged_files = 0;
8203 
8204 	*branch_name = NULL;
8205 	*branch_tip = NULL;
8206 	*fileindex = NULL;
8207 
8208 	err = lock_worktree(worktree, LOCK_EX);
8209 	if (err)
8210 		return err;
8211 
8212 	err = open_fileindex(fileindex, &fileindex_path, worktree);
8213 	if (err)
8214 		goto done;
8215 
8216 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
8217 	    &have_staged_files);
8218 	if (err && err->code != GOT_ERR_CANCELLED)
8219 		goto done;
8220 	if (have_staged_files) {
8221 		err = got_error(GOT_ERR_STAGED_PATHS);
8222 		goto done;
8223 	}
8224 
8225 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8226 	if (err)
8227 		goto done;
8228 
8229 	err = get_merge_commit_ref_name(&commit_refname, worktree);
8230 	if (err)
8231 		goto done;
8232 
8233 	err = got_ref_open(&branch_ref, repo, branch_refname, 0);
8234 	if (err)
8235 		goto done;
8236 
8237 	if (!got_ref_is_symbolic(branch_ref)) {
8238 		err = got_error_fmt(GOT_ERR_BAD_REF_TYPE,
8239 		    "%s is not a symbolic reference",
8240 		    got_ref_get_name(branch_ref));
8241 		goto done;
8242 	}
8243 	*branch_name = strdup(got_ref_get_symref_target(branch_ref));
8244 	if (*branch_name == NULL) {
8245 		err = got_error_from_errno("strdup");
8246 		goto done;
8247 	}
8248 
8249 	err = got_ref_open(&commit_ref, repo, commit_refname, 0);
8250 	if (err)
8251 		goto done;
8252 
8253 	err = got_ref_resolve(branch_tip, repo, commit_ref);
8254 	if (err)
8255 		goto done;
8256 done:
8257 	free(commit_refname);
8258 	free(branch_refname);
8259 	free(fileindex_path);
8260 	if (commit_ref)
8261 		got_ref_close(commit_ref);
8262 	if (branch_ref)
8263 		got_ref_close(branch_ref);
8264 	if (err) {
8265 		if (*branch_name) {
8266 			free(*branch_name);
8267 			*branch_name = NULL;
8268 		}
8269 		free(*branch_tip);
8270 		*branch_tip = NULL;
8271 		if (*fileindex) {
8272 			got_fileindex_free(*fileindex);
8273 			*fileindex = NULL;
8274 		}
8275 		lock_worktree(worktree, LOCK_SH);
8276 	}
8277 	return err;
8278 }
8279 
8280 const struct got_error *
8281 got_worktree_merge_abort(struct got_worktree *worktree,
8282     struct got_fileindex *fileindex, struct got_repository *repo,
8283     got_worktree_checkout_cb progress_cb, void *progress_arg)
8284 {
8285 	const struct got_error *err, *unlockerr, *sync_err;
8286 	struct got_object_id *commit_id = NULL;
8287 	struct got_commit_object *commit = NULL;
8288 	char *fileindex_path = NULL;
8289 	struct revert_file_args rfa;
8290 	struct got_object_id *tree_id = NULL;
8291 
8292 	err = got_object_open_as_commit(&commit, repo,
8293 	    worktree->base_commit_id);
8294 	if (err)
8295 		goto done;
8296 
8297 	err = got_object_id_by_path(&tree_id, repo, commit,
8298 	    worktree->path_prefix);
8299 	if (err)
8300 		goto done;
8301 
8302 	err = delete_merge_refs(worktree, repo);
8303 	if (err)
8304 		goto done;
8305 
8306 	err = get_fileindex_path(&fileindex_path, worktree);
8307 	if (err)
8308 		goto done;
8309 
8310 	rfa.worktree = worktree;
8311 	rfa.fileindex = fileindex;
8312 	rfa.progress_cb = progress_cb;
8313 	rfa.progress_arg = progress_arg;
8314 	rfa.patch_cb = NULL;
8315 	rfa.patch_arg = NULL;
8316 	rfa.repo = repo;
8317 	rfa.unlink_added_files = 1;
8318 	err = worktree_status(worktree, "", fileindex, repo,
8319 	    revert_file, &rfa, NULL, NULL, 1, 0);
8320 	if (err)
8321 		goto sync;
8322 
8323 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
8324 	    repo, progress_cb, progress_arg, NULL, NULL);
8325 sync:
8326 	sync_err = sync_fileindex(fileindex, fileindex_path);
8327 	if (sync_err && err == NULL)
8328 		err = sync_err;
8329 done:
8330 	free(tree_id);
8331 	free(commit_id);
8332 	if (commit)
8333 		got_object_commit_close(commit);
8334 	if (fileindex)
8335 		got_fileindex_free(fileindex);
8336 	free(fileindex_path);
8337 
8338 	unlockerr = lock_worktree(worktree, LOCK_SH);
8339 	if (unlockerr && err == NULL)
8340 		err = unlockerr;
8341 	return err;
8342 }
8343 
8344 struct check_stage_ok_arg {
8345 	struct got_object_id *head_commit_id;
8346 	struct got_worktree *worktree;
8347 	struct got_fileindex *fileindex;
8348 	struct got_repository *repo;
8349 	int have_changes;
8350 };
8351 
8352 static const struct got_error *
8353 check_stage_ok(void *arg, unsigned char status,
8354     unsigned char staged_status, const char *relpath,
8355     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8356     struct got_object_id *commit_id, int dirfd, const char *de_name)
8357 {
8358 	struct check_stage_ok_arg *a = arg;
8359 	const struct got_error *err = NULL;
8360 	struct got_fileindex_entry *ie;
8361 	struct got_object_id base_commit_id;
8362 	struct got_object_id *base_commit_idp = NULL;
8363 	char *in_repo_path = NULL, *p;
8364 
8365 	if (status == GOT_STATUS_UNVERSIONED ||
8366 	    status == GOT_STATUS_NO_CHANGE)
8367 		return NULL;
8368 	if (status == GOT_STATUS_NONEXISTENT)
8369 		return got_error_set_errno(ENOENT, relpath);
8370 
8371 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8372 	if (ie == NULL)
8373 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8374 
8375 	if (asprintf(&in_repo_path, "%s%s%s", a->worktree->path_prefix,
8376 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
8377 	    relpath) == -1)
8378 		return got_error_from_errno("asprintf");
8379 
8380 	if (got_fileindex_entry_has_commit(ie)) {
8381 		base_commit_idp = got_fileindex_entry_get_commit_id(
8382 		    &base_commit_id, ie);
8383 	}
8384 
8385 	if (status == GOT_STATUS_CONFLICT) {
8386 		err = got_error_path(ie->path, GOT_ERR_STAGE_CONFLICT);
8387 		goto done;
8388 	} else if (status != GOT_STATUS_ADD &&
8389 	    status != GOT_STATUS_MODIFY &&
8390 	    status != GOT_STATUS_DELETE) {
8391 		err = got_error_path(ie->path, GOT_ERR_FILE_STATUS);
8392 		goto done;
8393 	}
8394 
8395 	a->have_changes = 1;
8396 
8397 	p = in_repo_path;
8398 	while (p[0] == '/')
8399 		p++;
8400 	err = check_out_of_date(p, status, staged_status,
8401 	    blob_id, base_commit_idp, a->head_commit_id, a->repo,
8402 	    GOT_ERR_STAGE_OUT_OF_DATE);
8403 done:
8404 	free(in_repo_path);
8405 	return err;
8406 }
8407 
8408 struct stage_path_arg {
8409 	struct got_worktree *worktree;
8410 	struct got_fileindex *fileindex;
8411 	struct got_repository *repo;
8412 	got_worktree_status_cb status_cb;
8413 	void *status_arg;
8414 	got_worktree_patch_cb patch_cb;
8415 	void *patch_arg;
8416 	int staged_something;
8417 	int allow_bad_symlinks;
8418 };
8419 
8420 static const struct got_error *
8421 stage_path(void *arg, unsigned char status,
8422     unsigned char staged_status, const char *relpath,
8423     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8424     struct got_object_id *commit_id, int dirfd, const char *de_name)
8425 {
8426 	struct stage_path_arg *a = arg;
8427 	const struct got_error *err = NULL;
8428 	struct got_fileindex_entry *ie;
8429 	char *ondisk_path = NULL, *path_content = NULL;
8430 	uint32_t stage;
8431 	struct got_object_id *new_staged_blob_id = NULL;
8432 	struct stat sb;
8433 
8434 	if (status == GOT_STATUS_UNVERSIONED)
8435 		return NULL;
8436 
8437 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8438 	if (ie == NULL)
8439 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8440 
8441 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
8442 	    relpath)== -1)
8443 		return got_error_from_errno("asprintf");
8444 
8445 	switch (status) {
8446 	case GOT_STATUS_ADD:
8447 	case GOT_STATUS_MODIFY:
8448 		/* XXX could sb.st_mode be passed in by our caller? */
8449 		if (lstat(ondisk_path, &sb) == -1) {
8450 			err = got_error_from_errno2("lstat", ondisk_path);
8451 			break;
8452 		}
8453 		if (a->patch_cb) {
8454 			if (status == GOT_STATUS_ADD) {
8455 				int choice = GOT_PATCH_CHOICE_NONE;
8456 				err = (*a->patch_cb)(&choice, a->patch_arg,
8457 				    status, ie->path, NULL, 1, 1);
8458 				if (err)
8459 					break;
8460 				if (choice != GOT_PATCH_CHOICE_YES)
8461 					break;
8462 			} else {
8463 				err = create_patched_content(&path_content, 0,
8464 				    staged_blob_id ? staged_blob_id : blob_id,
8465 				    ondisk_path, dirfd, de_name, ie->path,
8466 				    a->repo, a->patch_cb, a->patch_arg);
8467 				if (err || path_content == NULL)
8468 					break;
8469 			}
8470 		}
8471 		err = got_object_blob_create(&new_staged_blob_id,
8472 		    path_content ? path_content : ondisk_path, a->repo);
8473 		if (err)
8474 			break;
8475 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
8476 		    SHA1_DIGEST_LENGTH);
8477 		if (status == GOT_STATUS_ADD || staged_status == GOT_STATUS_ADD)
8478 			stage = GOT_FILEIDX_STAGE_ADD;
8479 		else
8480 			stage = GOT_FILEIDX_STAGE_MODIFY;
8481 		got_fileindex_entry_stage_set(ie, stage);
8482 		if (S_ISLNK(sb.st_mode)) {
8483 			int is_bad_symlink = 0;
8484 			if (!a->allow_bad_symlinks) {
8485 				char target_path[PATH_MAX];
8486 				ssize_t target_len;
8487 				target_len = readlink(ondisk_path, target_path,
8488 				    sizeof(target_path));
8489 				if (target_len == -1) {
8490 					err = got_error_from_errno2("readlink",
8491 					    ondisk_path);
8492 					break;
8493 				}
8494 				err = is_bad_symlink_target(&is_bad_symlink,
8495 				    target_path, target_len, ondisk_path,
8496 				    a->worktree->root_path);
8497 				if (err)
8498 					break;
8499 				if (is_bad_symlink) {
8500 					err = got_error_path(ondisk_path,
8501 					    GOT_ERR_BAD_SYMLINK);
8502 					break;
8503 				}
8504 			}
8505 			if (is_bad_symlink)
8506 				got_fileindex_entry_staged_filetype_set(ie,
8507 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
8508 			else
8509 				got_fileindex_entry_staged_filetype_set(ie,
8510 				    GOT_FILEIDX_MODE_SYMLINK);
8511 		} else {
8512 			got_fileindex_entry_staged_filetype_set(ie,
8513 			    GOT_FILEIDX_MODE_REGULAR_FILE);
8514 		}
8515 		a->staged_something = 1;
8516 		if (a->status_cb == NULL)
8517 			break;
8518 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
8519 		    get_staged_status(ie), relpath, blob_id,
8520 		    new_staged_blob_id, NULL, dirfd, de_name);
8521 		if (err)
8522 			break;
8523 		/*
8524 		 * When staging the reverse of the staged diff,
8525 		 * implicitly unstage the file.
8526 		 */
8527 		if (memcmp(ie->staged_blob_sha1, ie->blob_sha1,
8528 		    sizeof(ie->blob_sha1)) == 0) {
8529 			got_fileindex_entry_stage_set(ie,
8530 			    GOT_FILEIDX_STAGE_NONE);
8531 		}
8532 		break;
8533 	case GOT_STATUS_DELETE:
8534 		if (staged_status == GOT_STATUS_DELETE)
8535 			break;
8536 		if (a->patch_cb) {
8537 			int choice = GOT_PATCH_CHOICE_NONE;
8538 			err = (*a->patch_cb)(&choice, a->patch_arg, status,
8539 			    ie->path, NULL, 1, 1);
8540 			if (err)
8541 				break;
8542 			if (choice == GOT_PATCH_CHOICE_NO)
8543 				break;
8544 			if (choice != GOT_PATCH_CHOICE_YES) {
8545 				err = got_error(GOT_ERR_PATCH_CHOICE);
8546 				break;
8547 			}
8548 		}
8549 		stage = GOT_FILEIDX_STAGE_DELETE;
8550 		got_fileindex_entry_stage_set(ie, stage);
8551 		a->staged_something = 1;
8552 		if (a->status_cb == NULL)
8553 			break;
8554 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
8555 		    get_staged_status(ie), relpath, NULL, NULL, NULL, dirfd,
8556 		    de_name);
8557 		break;
8558 	case GOT_STATUS_NO_CHANGE:
8559 		break;
8560 	case GOT_STATUS_CONFLICT:
8561 		err = got_error_path(relpath, GOT_ERR_STAGE_CONFLICT);
8562 		break;
8563 	case GOT_STATUS_NONEXISTENT:
8564 		err = got_error_set_errno(ENOENT, relpath);
8565 		break;
8566 	default:
8567 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
8568 		break;
8569 	}
8570 
8571 	if (path_content && unlink(path_content) == -1 && err == NULL)
8572 		err = got_error_from_errno2("unlink", path_content);
8573 	free(path_content);
8574 	free(ondisk_path);
8575 	free(new_staged_blob_id);
8576 	return err;
8577 }
8578 
8579 const struct got_error *
8580 got_worktree_stage(struct got_worktree *worktree,
8581     struct got_pathlist_head *paths,
8582     got_worktree_status_cb status_cb, void *status_arg,
8583     got_worktree_patch_cb patch_cb, void *patch_arg,
8584     int allow_bad_symlinks, struct got_repository *repo)
8585 {
8586 	const struct got_error *err = NULL, *sync_err, *unlockerr;
8587 	struct got_pathlist_entry *pe;
8588 	struct got_fileindex *fileindex = NULL;
8589 	char *fileindex_path = NULL;
8590 	struct got_reference *head_ref = NULL;
8591 	struct got_object_id *head_commit_id = NULL;
8592 	struct check_stage_ok_arg oka;
8593 	struct stage_path_arg spa;
8594 
8595 	err = lock_worktree(worktree, LOCK_EX);
8596 	if (err)
8597 		return err;
8598 
8599 	err = got_ref_open(&head_ref, repo,
8600 	    got_worktree_get_head_ref_name(worktree), 0);
8601 	if (err)
8602 		goto done;
8603 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
8604 	if (err)
8605 		goto done;
8606 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
8607 	if (err)
8608 		goto done;
8609 
8610 	/* Check pre-conditions before staging anything. */
8611 	oka.head_commit_id = head_commit_id;
8612 	oka.worktree = worktree;
8613 	oka.fileindex = fileindex;
8614 	oka.repo = repo;
8615 	oka.have_changes = 0;
8616 	TAILQ_FOREACH(pe, paths, entry) {
8617 		err = worktree_status(worktree, pe->path, fileindex, repo,
8618 		    check_stage_ok, &oka, NULL, NULL, 1, 0);
8619 		if (err)
8620 			goto done;
8621 	}
8622 	if (!oka.have_changes) {
8623 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
8624 		goto done;
8625 	}
8626 
8627 	spa.worktree = worktree;
8628 	spa.fileindex = fileindex;
8629 	spa.repo = repo;
8630 	spa.patch_cb = patch_cb;
8631 	spa.patch_arg = patch_arg;
8632 	spa.status_cb = status_cb;
8633 	spa.status_arg = status_arg;
8634 	spa.staged_something = 0;
8635 	spa.allow_bad_symlinks = allow_bad_symlinks;
8636 	TAILQ_FOREACH(pe, paths, entry) {
8637 		err = worktree_status(worktree, pe->path, fileindex, repo,
8638 		    stage_path, &spa, NULL, NULL, 1, 0);
8639 		if (err)
8640 			goto done;
8641 	}
8642 	if (!spa.staged_something) {
8643 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
8644 		goto done;
8645 	}
8646 
8647 	sync_err = sync_fileindex(fileindex, fileindex_path);
8648 	if (sync_err && err == NULL)
8649 		err = sync_err;
8650 done:
8651 	if (head_ref)
8652 		got_ref_close(head_ref);
8653 	free(head_commit_id);
8654 	free(fileindex_path);
8655 	if (fileindex)
8656 		got_fileindex_free(fileindex);
8657 	unlockerr = lock_worktree(worktree, LOCK_SH);
8658 	if (unlockerr && err == NULL)
8659 		err = unlockerr;
8660 	return err;
8661 }
8662 
8663 struct unstage_path_arg {
8664 	struct got_worktree *worktree;
8665 	struct got_fileindex *fileindex;
8666 	struct got_repository *repo;
8667 	got_worktree_checkout_cb progress_cb;
8668 	void *progress_arg;
8669 	got_worktree_patch_cb patch_cb;
8670 	void *patch_arg;
8671 };
8672 
8673 static const struct got_error *
8674 create_unstaged_content(char **path_unstaged_content,
8675     char **path_new_staged_content, struct got_object_id *blob_id,
8676     struct got_object_id *staged_blob_id, const char *relpath,
8677     struct got_repository *repo,
8678     got_worktree_patch_cb patch_cb, void *patch_arg)
8679 {
8680 	const struct got_error *err, *free_err;
8681 	struct got_blob_object *blob = NULL, *staged_blob = NULL;
8682 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL, *rejectfile = NULL;
8683 	char *path1 = NULL, *path2 = NULL, *label1 = NULL;
8684 	struct got_diffreg_result *diffreg_result = NULL;
8685 	int line_cur1 = 1, line_cur2 = 1, n = 0, nchunks_used = 0;
8686 	int have_content = 0, have_rejected_content = 0, i = 0, nchanges = 0;
8687 	int fd1 = -1, fd2 = -1;
8688 
8689 	*path_unstaged_content = NULL;
8690 	*path_new_staged_content = NULL;
8691 
8692 	err = got_object_id_str(&label1, blob_id);
8693 	if (err)
8694 		return err;
8695 
8696 	fd1 = got_opentempfd();
8697 	if (fd1 == -1) {
8698 		err = got_error_from_errno("got_opentempfd");
8699 		goto done;
8700 	}
8701 	fd2 = got_opentempfd();
8702 	if (fd2 == -1) {
8703 		err = got_error_from_errno("got_opentempfd");
8704 		goto done;
8705 	}
8706 
8707 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192, fd1);
8708 	if (err)
8709 		goto done;
8710 
8711 	err = got_opentemp_named(&path1, &f1, "got-unstage-blob-base", "");
8712 	if (err)
8713 		goto done;
8714 
8715 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
8716 	if (err)
8717 		goto done;
8718 
8719 	err = got_object_open_as_blob(&staged_blob, repo, staged_blob_id, 8192,
8720 	    fd2);
8721 	if (err)
8722 		goto done;
8723 
8724 	err = got_opentemp_named(&path2, &f2, "got-unstage-blob-staged", "");
8725 	if (err)
8726 		goto done;
8727 
8728 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f2, staged_blob);
8729 	if (err)
8730 		goto done;
8731 
8732 	err = got_diff_files(&diffreg_result, f1, 1, label1, f2, 1,
8733 	    path2, 3, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
8734 	if (err)
8735 		goto done;
8736 
8737 	err = got_opentemp_named(path_unstaged_content, &outfile,
8738 	    "got-unstaged-content", "");
8739 	if (err)
8740 		goto done;
8741 	err = got_opentemp_named(path_new_staged_content, &rejectfile,
8742 	    "got-new-staged-content", "");
8743 	if (err)
8744 		goto done;
8745 
8746 	if (fseek(f1, 0L, SEEK_SET) == -1) {
8747 		err = got_ferror(f1, GOT_ERR_IO);
8748 		goto done;
8749 	}
8750 	if (fseek(f2, 0L, SEEK_SET) == -1) {
8751 		err = got_ferror(f2, GOT_ERR_IO);
8752 		goto done;
8753 	}
8754 	/* Count the number of actual changes in the diff result. */
8755 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
8756 		struct diff_chunk_context cc = {};
8757 		diff_chunk_context_load_change(&cc, &nchunks_used,
8758 		    diffreg_result->result, n, 0);
8759 		nchanges++;
8760 	}
8761 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
8762 		int choice;
8763 		err = apply_or_reject_change(&choice, &nchunks_used,
8764 		    diffreg_result->result, n, relpath, f1, f2,
8765 		    &line_cur1, &line_cur2,
8766 		    outfile, rejectfile, ++i, nchanges, patch_cb, patch_arg);
8767 		if (err)
8768 			goto done;
8769 		if (choice == GOT_PATCH_CHOICE_YES)
8770 			have_content = 1;
8771 		else
8772 			have_rejected_content = 1;
8773 		if (choice == GOT_PATCH_CHOICE_QUIT)
8774 			break;
8775 	}
8776 	if (have_content || have_rejected_content)
8777 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
8778 		    outfile, rejectfile);
8779 done:
8780 	free(label1);
8781 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
8782 		err = got_error_from_errno("close");
8783 	if (blob)
8784 		got_object_blob_close(blob);
8785 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
8786 		err = got_error_from_errno("close");
8787 	if (staged_blob)
8788 		got_object_blob_close(staged_blob);
8789 	free_err = got_diffreg_result_free(diffreg_result);
8790 	if (free_err && err == NULL)
8791 		err = free_err;
8792 	if (f1 && fclose(f1) == EOF && err == NULL)
8793 		err = got_error_from_errno2("fclose", path1);
8794 	if (f2 && fclose(f2) == EOF && err == NULL)
8795 		err = got_error_from_errno2("fclose", path2);
8796 	if (outfile && fclose(outfile) == EOF && err == NULL)
8797 		err = got_error_from_errno2("fclose", *path_unstaged_content);
8798 	if (rejectfile && fclose(rejectfile) == EOF && err == NULL)
8799 		err = got_error_from_errno2("fclose", *path_new_staged_content);
8800 	if (path1 && unlink(path1) == -1 && err == NULL)
8801 		err = got_error_from_errno2("unlink", path1);
8802 	if (path2 && unlink(path2) == -1 && err == NULL)
8803 		err = got_error_from_errno2("unlink", path2);
8804 	if (err || !have_content) {
8805 		if (*path_unstaged_content &&
8806 		    unlink(*path_unstaged_content) == -1 && err == NULL)
8807 			err = got_error_from_errno2("unlink",
8808 			    *path_unstaged_content);
8809 		free(*path_unstaged_content);
8810 		*path_unstaged_content = NULL;
8811 	}
8812 	if (err || !have_content || !have_rejected_content) {
8813 		if (*path_new_staged_content &&
8814 		    unlink(*path_new_staged_content) == -1 && err == NULL)
8815 			err = got_error_from_errno2("unlink",
8816 			    *path_new_staged_content);
8817 		free(*path_new_staged_content);
8818 		*path_new_staged_content = NULL;
8819 	}
8820 	free(path1);
8821 	free(path2);
8822 	return err;
8823 }
8824 
8825 static const struct got_error *
8826 unstage_hunks(struct got_object_id *staged_blob_id,
8827     struct got_blob_object *blob_base,
8828     struct got_object_id *blob_id, struct got_fileindex_entry *ie,
8829     const char *ondisk_path, const char *label_orig,
8830     struct got_worktree *worktree, struct got_repository *repo,
8831     got_worktree_patch_cb patch_cb, void *patch_arg,
8832     got_worktree_checkout_cb progress_cb, void *progress_arg)
8833 {
8834 	const struct got_error *err = NULL;
8835 	char *path_unstaged_content = NULL;
8836 	char *path_new_staged_content = NULL;
8837 	char *parent = NULL, *base_path = NULL;
8838 	char *blob_base_path = NULL;
8839 	struct got_object_id *new_staged_blob_id = NULL;
8840 	FILE *f = NULL, *f_base = NULL, *f_deriv2 = NULL;
8841 	struct stat sb;
8842 
8843 	err = create_unstaged_content(&path_unstaged_content,
8844 	    &path_new_staged_content, blob_id, staged_blob_id,
8845 	    ie->path, repo, patch_cb, patch_arg);
8846 	if (err)
8847 		return err;
8848 
8849 	if (path_unstaged_content == NULL)
8850 		return NULL;
8851 
8852 	if (path_new_staged_content) {
8853 		err = got_object_blob_create(&new_staged_blob_id,
8854 		    path_new_staged_content, repo);
8855 		if (err)
8856 			goto done;
8857 	}
8858 
8859 	f = fopen(path_unstaged_content, "re");
8860 	if (f == NULL) {
8861 		err = got_error_from_errno2("fopen",
8862 		    path_unstaged_content);
8863 		goto done;
8864 	}
8865 	if (fstat(fileno(f), &sb) == -1) {
8866 		err = got_error_from_errno2("fstat", path_unstaged_content);
8867 		goto done;
8868 	}
8869 	if (got_fileindex_entry_staged_filetype_get(ie) ==
8870 	    GOT_FILEIDX_MODE_SYMLINK && sb.st_size < PATH_MAX) {
8871 		char link_target[PATH_MAX];
8872 		size_t r;
8873 		r = fread(link_target, 1, sizeof(link_target), f);
8874 		if (r == 0 && ferror(f)) {
8875 			err = got_error_from_errno("fread");
8876 			goto done;
8877 		}
8878 		if (r >= sizeof(link_target)) { /* should not happen */
8879 			err = got_error(GOT_ERR_NO_SPACE);
8880 			goto done;
8881 		}
8882 		link_target[r] = '\0';
8883 		err = merge_symlink(worktree, blob_base,
8884 		    ondisk_path, ie->path, label_orig, link_target,
8885 		    worktree->base_commit_id, repo, progress_cb,
8886 		    progress_arg);
8887 	} else {
8888 		int local_changes_subsumed;
8889 
8890 		err = got_path_dirname(&parent, ondisk_path);
8891 		if (err)
8892 			return err;
8893 
8894 		if (asprintf(&base_path, "%s/got-unstage-blob-orig",
8895 		    parent) == -1) {
8896 			err = got_error_from_errno("asprintf");
8897 			base_path = NULL;
8898 			goto done;
8899 		}
8900 
8901 		err = got_opentemp_named(&blob_base_path, &f_base,
8902 		    base_path, "");
8903 		if (err)
8904 			goto done;
8905 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_base,
8906 		    blob_base);
8907 		if (err)
8908 			goto done;
8909 
8910 		/*
8911 		 * In order the run a 3-way merge with a symlink we copy the symlink's
8912 		 * target path into a temporary file and use that file with diff3.
8913 		 */
8914 		if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
8915 			err = dump_symlink_target_path_to_file(&f_deriv2,
8916 			    ondisk_path);
8917 			if (err)
8918 				goto done;
8919 		} else {
8920 			int fd;
8921 			fd = open(ondisk_path,
8922 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
8923 			if (fd == -1) {
8924 				err = got_error_from_errno2("open", ondisk_path);
8925 				goto done;
8926 			}
8927 			f_deriv2 = fdopen(fd, "r");
8928 			if (f_deriv2 == NULL) {
8929 				err = got_error_from_errno2("fdopen", ondisk_path);
8930 				close(fd);
8931 				goto done;
8932 			}
8933 		}
8934 
8935 		err = merge_file(&local_changes_subsumed, worktree,
8936 		    f_base, f, f_deriv2, ondisk_path, ie->path,
8937 		    got_fileindex_perms_to_st(ie),
8938 		    label_orig, "unstaged", NULL, GOT_DIFF_ALGORITHM_MYERS,
8939 		    repo, progress_cb, progress_arg);
8940 	}
8941 	if (err)
8942 		goto done;
8943 
8944 	if (new_staged_blob_id) {
8945 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
8946 		    SHA1_DIGEST_LENGTH);
8947 	} else {
8948 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
8949 		got_fileindex_entry_staged_filetype_set(ie, 0);
8950 	}
8951 done:
8952 	free(new_staged_blob_id);
8953 	if (path_unstaged_content &&
8954 	    unlink(path_unstaged_content) == -1 && err == NULL)
8955 		err = got_error_from_errno2("unlink", path_unstaged_content);
8956 	if (path_new_staged_content &&
8957 	    unlink(path_new_staged_content) == -1 && err == NULL)
8958 		err = got_error_from_errno2("unlink", path_new_staged_content);
8959 	if (blob_base_path && unlink(blob_base_path) == -1 && err == NULL)
8960 		err = got_error_from_errno2("unlink", blob_base_path);
8961 	if (f_base && fclose(f_base) == EOF && err == NULL)
8962 		err = got_error_from_errno2("fclose", path_unstaged_content);
8963 	if (f && fclose(f) == EOF && err == NULL)
8964 		err = got_error_from_errno2("fclose", path_unstaged_content);
8965 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
8966 		err = got_error_from_errno2("fclose", ondisk_path);
8967 	free(path_unstaged_content);
8968 	free(path_new_staged_content);
8969 	free(blob_base_path);
8970 	free(parent);
8971 	free(base_path);
8972 	return err;
8973 }
8974 
8975 static const struct got_error *
8976 unstage_path(void *arg, unsigned char status,
8977     unsigned char staged_status, const char *relpath,
8978     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8979     struct got_object_id *commit_id, int dirfd, const char *de_name)
8980 {
8981 	const struct got_error *err = NULL;
8982 	struct unstage_path_arg *a = arg;
8983 	struct got_fileindex_entry *ie;
8984 	struct got_blob_object *blob_base = NULL, *blob_staged = NULL;
8985 	char *ondisk_path = NULL;
8986 	char *id_str = NULL, *label_orig = NULL;
8987 	int local_changes_subsumed;
8988 	struct stat sb;
8989 	int fd1 = -1, fd2 = -1;
8990 
8991 	if (staged_status != GOT_STATUS_ADD &&
8992 	    staged_status != GOT_STATUS_MODIFY &&
8993 	    staged_status != GOT_STATUS_DELETE)
8994 		return NULL;
8995 
8996 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8997 	if (ie == NULL)
8998 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8999 
9000 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, relpath)
9001 	    == -1)
9002 		return got_error_from_errno("asprintf");
9003 
9004 	err = got_object_id_str(&id_str,
9005 	    commit_id ? commit_id : a->worktree->base_commit_id);
9006 	if (err)
9007 		goto done;
9008 	if (asprintf(&label_orig, "%s: commit %s", GOT_MERGE_LABEL_BASE,
9009 	    id_str) == -1) {
9010 		err = got_error_from_errno("asprintf");
9011 		goto done;
9012 	}
9013 
9014 	fd1 = got_opentempfd();
9015 	if (fd1 == -1) {
9016 		err = got_error_from_errno("got_opentempfd");
9017 		goto done;
9018 	}
9019 	fd2 = got_opentempfd();
9020 	if (fd2 == -1) {
9021 		err = got_error_from_errno("got_opentempfd");
9022 		goto done;
9023 	}
9024 
9025 	switch (staged_status) {
9026 	case GOT_STATUS_MODIFY:
9027 		err = got_object_open_as_blob(&blob_base, a->repo,
9028 		    blob_id, 8192, fd1);
9029 		if (err)
9030 			break;
9031 		/* fall through */
9032 	case GOT_STATUS_ADD:
9033 		if (a->patch_cb) {
9034 			if (staged_status == GOT_STATUS_ADD) {
9035 				int choice = GOT_PATCH_CHOICE_NONE;
9036 				err = (*a->patch_cb)(&choice, a->patch_arg,
9037 				    staged_status, ie->path, NULL, 1, 1);
9038 				if (err)
9039 					break;
9040 				if (choice != GOT_PATCH_CHOICE_YES)
9041 					break;
9042 			} else {
9043 				err = unstage_hunks(staged_blob_id,
9044 				    blob_base, blob_id, ie, ondisk_path,
9045 				    label_orig, a->worktree, a->repo,
9046 				    a->patch_cb, a->patch_arg,
9047 				    a->progress_cb, a->progress_arg);
9048 				break; /* Done with this file. */
9049 			}
9050 		}
9051 		err = got_object_open_as_blob(&blob_staged, a->repo,
9052 		    staged_blob_id, 8192, fd2);
9053 		if (err)
9054 			break;
9055 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
9056 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
9057 		case GOT_FILEIDX_MODE_REGULAR_FILE:
9058 			err = merge_blob(&local_changes_subsumed, a->worktree,
9059 			    blob_base, ondisk_path, relpath,
9060 			    got_fileindex_perms_to_st(ie), label_orig,
9061 			    blob_staged, commit_id ? commit_id :
9062 			    a->worktree->base_commit_id, a->repo,
9063 			    a->progress_cb, a->progress_arg);
9064 			break;
9065 		case GOT_FILEIDX_MODE_SYMLINK:
9066 			if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
9067 				char *staged_target;
9068 				err = got_object_blob_read_to_str(
9069 				    &staged_target, blob_staged);
9070 				if (err)
9071 					goto done;
9072 				err = merge_symlink(a->worktree, blob_base,
9073 				    ondisk_path, relpath, label_orig,
9074 				    staged_target, commit_id ? commit_id :
9075 				    a->worktree->base_commit_id,
9076 				    a->repo, a->progress_cb, a->progress_arg);
9077 				free(staged_target);
9078 			} else {
9079 				err = merge_blob(&local_changes_subsumed,
9080 				    a->worktree, blob_base, ondisk_path,
9081 				    relpath, got_fileindex_perms_to_st(ie),
9082 				    label_orig, blob_staged,
9083 				    commit_id ? commit_id :
9084 				    a->worktree->base_commit_id, a->repo,
9085 				    a->progress_cb, a->progress_arg);
9086 			}
9087 			break;
9088 		default:
9089 			err = got_error_path(relpath, GOT_ERR_BAD_FILETYPE);
9090 			break;
9091 		}
9092 		if (err == NULL) {
9093 			got_fileindex_entry_stage_set(ie,
9094 			    GOT_FILEIDX_STAGE_NONE);
9095 			got_fileindex_entry_staged_filetype_set(ie, 0);
9096 		}
9097 		break;
9098 	case GOT_STATUS_DELETE:
9099 		if (a->patch_cb) {
9100 			int choice = GOT_PATCH_CHOICE_NONE;
9101 			err = (*a->patch_cb)(&choice, a->patch_arg,
9102 			    staged_status, ie->path, NULL, 1, 1);
9103 			if (err)
9104 				break;
9105 			if (choice == GOT_PATCH_CHOICE_NO)
9106 				break;
9107 			if (choice != GOT_PATCH_CHOICE_YES) {
9108 				err = got_error(GOT_ERR_PATCH_CHOICE);
9109 				break;
9110 			}
9111 		}
9112 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
9113 		got_fileindex_entry_staged_filetype_set(ie, 0);
9114 		err = get_file_status(&status, &sb, ie, ondisk_path,
9115 		    dirfd, de_name, a->repo);
9116 		if (err)
9117 			break;
9118 		err = (*a->progress_cb)(a->progress_arg, status, relpath);
9119 		break;
9120 	}
9121 done:
9122 	free(ondisk_path);
9123 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
9124 		err = got_error_from_errno("close");
9125 	if (blob_base)
9126 		got_object_blob_close(blob_base);
9127 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
9128 		err = got_error_from_errno("close");
9129 	if (blob_staged)
9130 		got_object_blob_close(blob_staged);
9131 	free(id_str);
9132 	free(label_orig);
9133 	return err;
9134 }
9135 
9136 const struct got_error *
9137 got_worktree_unstage(struct got_worktree *worktree,
9138     struct got_pathlist_head *paths,
9139     got_worktree_checkout_cb progress_cb, void *progress_arg,
9140     got_worktree_patch_cb patch_cb, void *patch_arg,
9141     struct got_repository *repo)
9142 {
9143 	const struct got_error *err = NULL, *sync_err, *unlockerr;
9144 	struct got_pathlist_entry *pe;
9145 	struct got_fileindex *fileindex = NULL;
9146 	char *fileindex_path = NULL;
9147 	struct unstage_path_arg upa;
9148 
9149 	err = lock_worktree(worktree, LOCK_EX);
9150 	if (err)
9151 		return err;
9152 
9153 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
9154 	if (err)
9155 		goto done;
9156 
9157 	upa.worktree = worktree;
9158 	upa.fileindex = fileindex;
9159 	upa.repo = repo;
9160 	upa.progress_cb = progress_cb;
9161 	upa.progress_arg = progress_arg;
9162 	upa.patch_cb = patch_cb;
9163 	upa.patch_arg = patch_arg;
9164 	TAILQ_FOREACH(pe, paths, entry) {
9165 		err = worktree_status(worktree, pe->path, fileindex, repo,
9166 		    unstage_path, &upa, NULL, NULL, 1, 0);
9167 		if (err)
9168 			goto done;
9169 	}
9170 
9171 	sync_err = sync_fileindex(fileindex, fileindex_path);
9172 	if (sync_err && err == NULL)
9173 		err = sync_err;
9174 done:
9175 	free(fileindex_path);
9176 	if (fileindex)
9177 		got_fileindex_free(fileindex);
9178 	unlockerr = lock_worktree(worktree, LOCK_SH);
9179 	if (unlockerr && err == NULL)
9180 		err = unlockerr;
9181 	return err;
9182 }
9183 
9184 struct report_file_info_arg {
9185 	struct got_worktree *worktree;
9186 	got_worktree_path_info_cb info_cb;
9187 	void *info_arg;
9188 	struct got_pathlist_head *paths;
9189 	got_cancel_cb cancel_cb;
9190 	void *cancel_arg;
9191 };
9192 
9193 static const struct got_error *
9194 report_file_info(void *arg, struct got_fileindex_entry *ie)
9195 {
9196 	struct report_file_info_arg *a = arg;
9197 	struct got_pathlist_entry *pe;
9198 	struct got_object_id blob_id, staged_blob_id, commit_id;
9199 	struct got_object_id *blob_idp = NULL, *staged_blob_idp = NULL;
9200 	struct got_object_id *commit_idp = NULL;
9201 	int stage;
9202 
9203 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
9204 		return got_error(GOT_ERR_CANCELLED);
9205 
9206 	TAILQ_FOREACH(pe, a->paths, entry) {
9207 		if (pe->path_len == 0 || strcmp(pe->path, ie->path) == 0 ||
9208 		    got_path_is_child(ie->path, pe->path, pe->path_len))
9209 			break;
9210 	}
9211 	if (pe == NULL) /* not found */
9212 		return NULL;
9213 
9214 	if (got_fileindex_entry_has_blob(ie))
9215 		blob_idp = got_fileindex_entry_get_blob_id(&blob_id, ie);
9216 	stage = got_fileindex_entry_stage_get(ie);
9217 	if (stage == GOT_FILEIDX_STAGE_MODIFY ||
9218 	    stage == GOT_FILEIDX_STAGE_ADD) {
9219 		staged_blob_idp = got_fileindex_entry_get_staged_blob_id(
9220 		    &staged_blob_id, ie);
9221 	}
9222 
9223 	if (got_fileindex_entry_has_commit(ie))
9224 		commit_idp = got_fileindex_entry_get_commit_id(&commit_id, ie);
9225 
9226 	return a->info_cb(a->info_arg, ie->path, got_fileindex_perms_to_st(ie),
9227 	    (time_t)ie->mtime_sec, blob_idp, staged_blob_idp, commit_idp);
9228 }
9229 
9230 const struct got_error *
9231 got_worktree_path_info(struct got_worktree *worktree,
9232     struct got_pathlist_head *paths,
9233     got_worktree_path_info_cb info_cb, void *info_arg,
9234     got_cancel_cb cancel_cb, void *cancel_arg)
9235 
9236 {
9237 	const struct got_error *err = NULL, *unlockerr;
9238 	struct got_fileindex *fileindex = NULL;
9239 	char *fileindex_path = NULL;
9240 	struct report_file_info_arg arg;
9241 
9242 	err = lock_worktree(worktree, LOCK_SH);
9243 	if (err)
9244 		return err;
9245 
9246 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
9247 	if (err)
9248 		goto done;
9249 
9250 	arg.worktree = worktree;
9251 	arg.info_cb = info_cb;
9252 	arg.info_arg = info_arg;
9253 	arg.paths = paths;
9254 	arg.cancel_cb = cancel_cb;
9255 	arg.cancel_arg = cancel_arg;
9256 	err = got_fileindex_for_each_entry_safe(fileindex, report_file_info,
9257 	    &arg);
9258 done:
9259 	free(fileindex_path);
9260 	if (fileindex)
9261 		got_fileindex_free(fileindex);
9262 	unlockerr = lock_worktree(worktree, LOCK_UN);
9263 	if (unlockerr && err == NULL)
9264 		err = unlockerr;
9265 	return err;
9266 }
9267 
9268 static const struct got_error *
9269 patch_check_path(const char *p, char **path, unsigned char *status,
9270     unsigned char *staged_status, struct got_fileindex *fileindex,
9271     struct got_worktree *worktree, struct got_repository *repo)
9272 {
9273 	const struct got_error *err;
9274 	struct got_fileindex_entry *ie;
9275 	struct stat sb;
9276 	char *ondisk_path = NULL;
9277 
9278 	err = got_worktree_resolve_path(path, worktree, p);
9279 	if (err)
9280 		return err;
9281 
9282 	if (asprintf(&ondisk_path, "%s%s%s", worktree->root_path,
9283 	    *path[0] ? "/" : "", *path) == -1)
9284 		return got_error_from_errno("asprintf");
9285 
9286 	ie = got_fileindex_entry_get(fileindex, *path, strlen(*path));
9287 	if (ie) {
9288 		*staged_status = get_staged_status(ie);
9289 		err = get_file_status(status, &sb, ie, ondisk_path, -1, NULL,
9290 		    repo);
9291 		if (err)
9292 			goto done;
9293 	} else {
9294 		*staged_status = GOT_STATUS_NO_CHANGE;
9295 		*status = GOT_STATUS_UNVERSIONED;
9296 		if (lstat(ondisk_path, &sb) == -1) {
9297 			if (errno != ENOENT) {
9298 				err = got_error_from_errno2("lstat",
9299 				    ondisk_path);
9300 				goto done;
9301 			}
9302 			*status = GOT_STATUS_NONEXISTENT;
9303 		}
9304 	}
9305 
9306 done:
9307 	free(ondisk_path);
9308 	return err;
9309 }
9310 
9311 static const struct got_error *
9312 patch_can_rm(const char *path, unsigned char status,
9313     unsigned char staged_status)
9314 {
9315 	if (status == GOT_STATUS_NONEXISTENT)
9316 		return got_error_set_errno(ENOENT, path);
9317 	if (status != GOT_STATUS_NO_CHANGE &&
9318 	    status != GOT_STATUS_ADD &&
9319 	    status != GOT_STATUS_MODIFY &&
9320 	    status != GOT_STATUS_MODE_CHANGE)
9321 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9322 	if (staged_status == GOT_STATUS_DELETE)
9323 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9324 	return NULL;
9325 }
9326 
9327 static const struct got_error *
9328 patch_can_add(const char *path, unsigned char status)
9329 {
9330 	if (status != GOT_STATUS_NONEXISTENT)
9331 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9332 	return NULL;
9333 }
9334 
9335 static const struct got_error *
9336 patch_can_edit(const char *path, unsigned char status,
9337     unsigned char staged_status)
9338 {
9339 	if (status == GOT_STATUS_NONEXISTENT)
9340 		return got_error_set_errno(ENOENT, path);
9341 	if (status != GOT_STATUS_NO_CHANGE &&
9342 	    status != GOT_STATUS_ADD &&
9343 	    status != GOT_STATUS_MODIFY)
9344 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9345 	if (staged_status == GOT_STATUS_DELETE)
9346 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9347 	return NULL;
9348 }
9349 
9350 const struct got_error *
9351 got_worktree_patch_prepare(struct got_fileindex **fileindex,
9352     char **fileindex_path, struct got_worktree *worktree)
9353 {
9354 	return open_fileindex(fileindex, fileindex_path, worktree);
9355 }
9356 
9357 const struct got_error *
9358 got_worktree_patch_check_path(const char *old, const char *new,
9359     char **oldpath, char **newpath, struct got_worktree *worktree,
9360     struct got_repository *repo, struct got_fileindex *fileindex)
9361 {
9362 	const struct got_error *err = NULL;
9363 	int file_renamed = 0;
9364 	unsigned char status_old, staged_status_old;
9365 	unsigned char status_new, staged_status_new;
9366 
9367 	*oldpath = NULL;
9368 	*newpath = NULL;
9369 
9370 	err = patch_check_path(old != NULL ? old : new, oldpath,
9371 	    &status_old, &staged_status_old, fileindex, worktree, repo);
9372 	if (err)
9373 		goto done;
9374 
9375 	err = patch_check_path(new != NULL ? new : old, newpath,
9376 	    &status_new, &staged_status_new, fileindex, worktree, repo);
9377 	if (err)
9378 		goto done;
9379 
9380 	if (old != NULL && new != NULL && strcmp(old, new) != 0)
9381 		file_renamed = 1;
9382 
9383 	if (old != NULL && new == NULL)
9384 		err = patch_can_rm(*oldpath, status_old, staged_status_old);
9385 	else if (file_renamed) {
9386 		err = patch_can_rm(*oldpath, status_old, staged_status_old);
9387 		if (err == NULL)
9388 			err = patch_can_add(*newpath, status_new);
9389 	} else if (old == NULL)
9390 		err = patch_can_add(*newpath, status_new);
9391 	else
9392 		err = patch_can_edit(*newpath, status_new, staged_status_new);
9393 
9394 done:
9395 	if (err) {
9396 		free(*oldpath);
9397 		*oldpath = NULL;
9398 		free(*newpath);
9399 		*newpath = NULL;
9400 	}
9401 	return err;
9402 }
9403 
9404 const struct got_error *
9405 got_worktree_patch_schedule_add(const char *path, struct got_repository *repo,
9406     struct got_worktree *worktree, struct got_fileindex *fileindex,
9407     got_worktree_checkout_cb progress_cb, void *progress_arg)
9408 {
9409 	struct schedule_addition_args saa;
9410 
9411 	memset(&saa, 0, sizeof(saa));
9412 	saa.worktree = worktree;
9413 	saa.fileindex = fileindex;
9414 	saa.progress_cb = progress_cb;
9415 	saa.progress_arg = progress_arg;
9416 	saa.repo = repo;
9417 
9418 	return worktree_status(worktree, path, fileindex, repo,
9419 	    schedule_addition, &saa, NULL, NULL, 1, 0);
9420 }
9421 
9422 const struct got_error *
9423 got_worktree_patch_schedule_rm(const char *path, struct got_repository *repo,
9424     struct got_worktree *worktree, struct got_fileindex *fileindex,
9425     got_worktree_delete_cb progress_cb, void *progress_arg)
9426 {
9427 	struct schedule_deletion_args sda;
9428 
9429 	memset(&sda, 0, sizeof(sda));
9430 	sda.worktree = worktree;
9431 	sda.fileindex = fileindex;
9432 	sda.progress_cb = progress_cb;
9433 	sda.progress_arg = progress_arg;
9434 	sda.repo = repo;
9435 	sda.delete_local_mods = 0;
9436 	sda.keep_on_disk = 0;
9437 	sda.ignore_missing_paths = 0;
9438 	sda.status_codes = NULL;
9439 
9440 	return worktree_status(worktree, path, fileindex, repo,
9441 	    schedule_for_deletion, &sda, NULL, NULL, 1, 1);
9442 }
9443 
9444 const struct got_error *
9445 got_worktree_patch_complete(struct got_fileindex *fileindex,
9446     const char *fileindex_path)
9447 {
9448 	const struct got_error *err = NULL;
9449 
9450 	err = sync_fileindex(fileindex, fileindex_path);
9451 	got_fileindex_free(fileindex);
9452 
9453 	return err;
9454 }