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