1 /*
2  * Copyright (c) 2018, 2019 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/limits.h>
19 #include <sys/queue.h>
20 #include <sys/tree.h>
21 
22 #include <dirent.h>
23 #include <stddef.h>
24 #include <string.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <fcntl.h>
28 #include <errno.h>
29 #include <unistd.h>
30 #include <sha1.h>
31 #include <zlib.h>
32 #include <fnmatch.h>
33 #include <libgen.h>
34 #include <uuid.h>
35 #include <util.h>
36 
37 #include "got_error.h"
38 #include "got_repository.h"
39 #include "got_reference.h"
40 #include "got_object.h"
41 #include "got_path.h"
42 #include "got_worktree.h"
43 #include "got_opentemp.h"
44 #include "got_diff.h"
45 
46 #include "got_lib_worktree.h"
47 #include "got_lib_sha1.h"
48 #include "got_lib_fileindex.h"
49 #include "got_lib_inflate.h"
50 #include "got_lib_delta.h"
51 #include "got_lib_object.h"
52 #include "got_lib_object_parse.h"
53 #include "got_lib_object_create.h"
54 #include "got_lib_object_idset.h"
55 #include "got_lib_diff.h"
56 
57 #ifndef MIN
58 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
59 #endif
60 
61 static const struct got_error *
62 create_meta_file(const char *path_got, const char *name, const char *content)
63 {
64 	const struct got_error *err = NULL;
65 	char *path;
66 
67 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
68 		return got_error_from_errno("asprintf");
69 
70 	err = got_path_create_file(path, content);
71 	free(path);
72 	return err;
73 }
74 
75 static const struct got_error *
76 update_meta_file(const char *path_got, const char *name, const char *content)
77 {
78 	const struct got_error *err = NULL;
79 	FILE *tmpfile = NULL;
80 	char *tmppath = NULL;
81 	char *path = NULL;
82 
83 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
84 		err = got_error_from_errno("asprintf");
85 		path = NULL;
86 		goto done;
87 	}
88 
89 	err = got_opentemp_named(&tmppath, &tmpfile, path);
90 	if (err)
91 		goto done;
92 
93 	if (content) {
94 		int len = fprintf(tmpfile, "%s\n", content);
95 		if (len != strlen(content) + 1) {
96 			err = got_error_from_errno2("fprintf", tmppath);
97 			goto done;
98 		}
99 	}
100 
101 	if (rename(tmppath, path) != 0) {
102 		err = got_error_from_errno3("rename", tmppath, path);
103 		unlink(tmppath);
104 		goto done;
105 	}
106 
107 done:
108 	if (fclose(tmpfile) != 0 && err == NULL)
109 		err = got_error_from_errno2("fclose", tmppath);
110 	free(tmppath);
111 	return err;
112 }
113 
114 static const struct got_error *
115 read_meta_file(char **content, const char *path_got, const char *name)
116 {
117 	const struct got_error *err = NULL;
118 	char *path;
119 	int fd = -1;
120 	ssize_t n;
121 	struct stat sb;
122 
123 	*content = NULL;
124 
125 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
126 		err = got_error_from_errno("asprintf");
127 		path = NULL;
128 		goto done;
129 	}
130 
131 	fd = open(path, O_RDONLY | O_NOFOLLOW);
132 	if (fd == -1) {
133 		if (errno == ENOENT)
134 			err = got_error(GOT_ERR_WORKTREE_META);
135 		else
136 			err = got_error_from_errno2("open", path);
137 		goto done;
138 	}
139 	if (flock(fd, LOCK_SH | LOCK_NB) == -1) {
140 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
141 		    : got_error_from_errno2("flock", path));
142 		goto done;
143 	}
144 
145 	if (lstat(path, &sb) != 0) {
146 		err = got_error_from_errno2("lstat", path);
147 		goto done;
148 	}
149 	*content = calloc(1, sb.st_size);
150 	if (*content == NULL) {
151 		err = got_error_from_errno("calloc");
152 		goto done;
153 	}
154 
155 	n = read(fd, *content, sb.st_size);
156 	if (n != sb.st_size) {
157 		err = (n == -1 ? got_error_from_errno2("read", path) :
158 		    got_error(GOT_ERR_WORKTREE_META));
159 		goto done;
160 	}
161 	if ((*content)[sb.st_size - 1] != '\n') {
162 		err = got_error(GOT_ERR_WORKTREE_META);
163 		goto done;
164 	}
165 	(*content)[sb.st_size - 1] = '\0';
166 
167 done:
168 	if (fd != -1 && close(fd) == -1 && err == NULL)
169 		err = got_error_from_errno2("close", path_got);
170 	free(path);
171 	if (err) {
172 		free(*content);
173 		*content = NULL;
174 	}
175 	return err;
176 }
177 
178 static const struct got_error *
179 write_head_ref(const char *path_got, struct got_reference *head_ref)
180 {
181 	const struct got_error *err = NULL;
182 	char *refstr = NULL;
183 
184 	if (got_ref_is_symbolic(head_ref)) {
185 		refstr = got_ref_to_str(head_ref);
186 		if (refstr == NULL)
187 			return got_error_from_errno("got_ref_to_str");
188 	} else {
189 		refstr = strdup(got_ref_get_name(head_ref));
190 		if (refstr == NULL)
191 			return got_error_from_errno("strdup");
192 	}
193 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
194 	free(refstr);
195 	return err;
196 }
197 
198 const struct got_error *
199 got_worktree_init(const char *path, struct got_reference *head_ref,
200     const char *prefix, struct got_repository *repo)
201 {
202 	const struct got_error *err = NULL;
203 	struct got_object_id *commit_id = NULL;
204 	uuid_t uuid;
205 	uint32_t uuid_status;
206 	int obj_type;
207 	char *path_got = NULL;
208 	char *formatstr = NULL;
209 	char *absprefix = NULL;
210 	char *basestr = NULL;
211 	char *uuidstr = NULL;
212 
213 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
214 		err = got_error(GOT_ERR_WORKTREE_REPO);
215 		goto done;
216 	}
217 
218 	err = got_ref_resolve(&commit_id, repo, head_ref);
219 	if (err)
220 		return err;
221 	err = got_object_get_type(&obj_type, repo, commit_id);
222 	if (err)
223 		return err;
224 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
225 		return got_error(GOT_ERR_OBJ_TYPE);
226 
227 	if (!got_path_is_absolute(prefix)) {
228 		if (asprintf(&absprefix, "/%s", prefix) == -1)
229 			return got_error_from_errno("asprintf");
230 	}
231 
232 	/* Create top-level directory (may already exist). */
233 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
234 		err = got_error_from_errno2("mkdir", path);
235 		goto done;
236 	}
237 
238 	/* Create .got directory (may already exist). */
239 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
240 		err = got_error_from_errno("asprintf");
241 		goto done;
242 	}
243 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
244 		err = got_error_from_errno2("mkdir", path_got);
245 		goto done;
246 	}
247 
248 	/* Create an empty lock file. */
249 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
250 	if (err)
251 		goto done;
252 
253 	/* Create an empty file index. */
254 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
255 	if (err)
256 		goto done;
257 
258 	/* Write the HEAD reference. */
259 	err = write_head_ref(path_got, head_ref);
260 	if (err)
261 		goto done;
262 
263 	/* Record our base commit. */
264 	err = got_object_id_str(&basestr, commit_id);
265 	if (err)
266 		goto done;
267 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
268 	if (err)
269 		goto done;
270 
271 	/* Store path to repository. */
272 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
273 	    got_repo_get_path(repo));
274 	if (err)
275 		goto done;
276 
277 	/* Store in-repository path prefix. */
278 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
279 	    absprefix ? absprefix : prefix);
280 	if (err)
281 		goto done;
282 
283 	/* Generate UUID. */
284 	uuid_create(&uuid, &uuid_status);
285 	if (uuid_status != uuid_s_ok) {
286 		err = got_error_uuid(uuid_status);
287 		goto done;
288 	}
289 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
290 	if (uuid_status != uuid_s_ok) {
291 		err = got_error_uuid(uuid_status);
292 		goto done;
293 	}
294 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
295 	if (err)
296 		goto done;
297 
298 	/* Stamp work tree with format file. */
299 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
300 		err = got_error_from_errno("asprintf");
301 		goto done;
302 	}
303 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
304 	if (err)
305 		goto done;
306 
307 done:
308 	free(commit_id);
309 	free(path_got);
310 	free(formatstr);
311 	free(absprefix);
312 	free(basestr);
313 	free(uuidstr);
314 	return err;
315 }
316 
317 static const struct got_error *
318 open_worktree(struct got_worktree **worktree, const char *path)
319 {
320 	const struct got_error *err = NULL;
321 	char *path_got;
322 	char *formatstr = NULL;
323 	char *uuidstr = NULL;
324 	char *path_lock = NULL;
325 	char *base_commit_id_str = NULL;
326 	int version, fd = -1;
327 	const char *errstr;
328 	struct got_repository *repo = NULL;
329 	uint32_t uuid_status;
330 
331 	*worktree = NULL;
332 
333 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
334 		err = got_error_from_errno("asprintf");
335 		path_got = NULL;
336 		goto done;
337 	}
338 
339 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
340 		err = got_error_from_errno("asprintf");
341 		path_lock = NULL;
342 		goto done;
343 	}
344 
345 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
346 	if (fd == -1) {
347 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
348 		    : got_error_from_errno2("open", path_lock));
349 		goto done;
350 	}
351 
352 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
353 	if (err)
354 		goto done;
355 
356 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
357 	if (errstr) {
358 		err = got_error(GOT_ERR_WORKTREE_META);
359 		goto done;
360 	}
361 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
362 		err = got_error(GOT_ERR_WORKTREE_VERS);
363 		goto done;
364 	}
365 
366 	*worktree = calloc(1, sizeof(**worktree));
367 	if (*worktree == NULL) {
368 		err = got_error_from_errno("calloc");
369 		goto done;
370 	}
371 	(*worktree)->lockfd = -1;
372 
373 	(*worktree)->root_path = strdup(path);
374 	if ((*worktree)->root_path == NULL) {
375 		err = got_error_from_errno("strdup");
376 		goto done;
377 	}
378 	err = read_meta_file(&(*worktree)->repo_path, path_got,
379 	    GOT_WORKTREE_REPOSITORY);
380 	if (err)
381 		goto done;
382 
383 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
384 	    GOT_WORKTREE_PATH_PREFIX);
385 	if (err)
386 		goto done;
387 
388 	err = read_meta_file(&base_commit_id_str, path_got,
389 	    GOT_WORKTREE_BASE_COMMIT);
390 	if (err)
391 		goto done;
392 
393 	err = read_meta_file(&uuidstr, path_got, GOT_WORKTREE_UUID);
394 	if (err)
395 		goto done;
396 	uuid_from_string(uuidstr, &(*worktree)->uuid, &uuid_status);
397 	if (uuid_status != uuid_s_ok) {
398 		err = got_error_uuid(uuid_status);
399 		goto done;
400 	}
401 
402 	err = got_repo_open(&repo, (*worktree)->repo_path);
403 	if (err)
404 		goto done;
405 
406 	err = got_object_resolve_id_str(&(*worktree)->base_commit_id, repo,
407 	    base_commit_id_str);
408 	if (err)
409 		goto done;
410 
411 	err = read_meta_file(&(*worktree)->head_ref_name, path_got,
412 	    GOT_WORKTREE_HEAD_REF);
413 done:
414 	if (repo)
415 		got_repo_close(repo);
416 	free(path_got);
417 	free(path_lock);
418 	free(base_commit_id_str);
419 	free(uuidstr);
420 	free(formatstr);
421 	if (err) {
422 		if (fd != -1)
423 			close(fd);
424 		if (*worktree != NULL)
425 			got_worktree_close(*worktree);
426 		*worktree = NULL;
427 	} else
428 		(*worktree)->lockfd = fd;
429 
430 	return err;
431 }
432 
433 const struct got_error *
434 got_worktree_open(struct got_worktree **worktree, const char *path)
435 {
436 	const struct got_error *err = NULL;
437 
438 	do {
439 		err = open_worktree(worktree, path);
440 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT))
441 			return err;
442 		if (*worktree)
443 			return NULL;
444 		path = dirname(path);
445 		if (path == NULL)
446 			return got_error_from_errno2("dirname", path);
447 	} while (!((path[0] == '.' || path[0] == '/') && path[1] == '\0'));
448 
449 	return got_error(GOT_ERR_NOT_WORKTREE);
450 }
451 
452 const struct got_error *
453 got_worktree_close(struct got_worktree *worktree)
454 {
455 	const struct got_error *err = NULL;
456 	free(worktree->root_path);
457 	free(worktree->repo_path);
458 	free(worktree->path_prefix);
459 	free(worktree->base_commit_id);
460 	free(worktree->head_ref_name);
461 	if (worktree->lockfd != -1)
462 		if (close(worktree->lockfd) != 0)
463 			err = got_error_from_errno2("close",
464 			    got_worktree_get_root_path(worktree));
465 	free(worktree);
466 	return err;
467 }
468 
469 const char *
470 got_worktree_get_root_path(struct got_worktree *worktree)
471 {
472 	return worktree->root_path;
473 }
474 
475 const char *
476 got_worktree_get_repo_path(struct got_worktree *worktree)
477 {
478 	return worktree->repo_path;
479 }
480 
481 const char *
482 got_worktree_get_path_prefix(struct got_worktree *worktree)
483 {
484 	return worktree->path_prefix;
485 }
486 
487 const struct got_error *
488 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
489     const char *path_prefix)
490 {
491 	char *absprefix = NULL;
492 
493 	if (!got_path_is_absolute(path_prefix)) {
494 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
495 			return got_error_from_errno("asprintf");
496 	}
497 	*match = (strcmp(absprefix ? absprefix : path_prefix,
498 	    worktree->path_prefix) == 0);
499 	free(absprefix);
500 	return NULL;
501 }
502 
503 const char *
504 got_worktree_get_head_ref_name(struct got_worktree *worktree)
505 {
506 	return worktree->head_ref_name;
507 }
508 
509 const struct got_error *
510 got_worktree_set_head_ref(struct got_worktree *worktree,
511     struct got_reference *head_ref)
512 {
513 	const struct got_error *err = NULL;
514 	char *path_got = NULL, *head_ref_name = NULL;
515 
516 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
517 	    GOT_WORKTREE_GOT_DIR) == -1) {
518 		err = got_error_from_errno("asprintf");
519 		path_got = NULL;
520 		goto done;
521 	}
522 
523 	head_ref_name = strdup(got_ref_get_name(head_ref));
524 	if (head_ref_name == NULL) {
525 		err = got_error_from_errno("strdup");
526 		goto done;
527 	}
528 
529 	err = write_head_ref(path_got, head_ref);
530 	if (err)
531 		goto done;
532 
533 	free(worktree->head_ref_name);
534 	worktree->head_ref_name = head_ref_name;
535 done:
536 	free(path_got);
537 	if (err)
538 		free(head_ref_name);
539 	return err;
540 }
541 
542 struct got_object_id *
543 got_worktree_get_base_commit_id(struct got_worktree *worktree)
544 {
545 	return worktree->base_commit_id;
546 }
547 
548 const struct got_error *
549 got_worktree_set_base_commit_id(struct got_worktree *worktree,
550     struct got_repository *repo, struct got_object_id *commit_id)
551 {
552 	const struct got_error *err;
553 	struct got_object *obj = NULL;
554 	char *id_str = NULL;
555 	char *path_got = NULL;
556 
557 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
558 	    GOT_WORKTREE_GOT_DIR) == -1) {
559 		err = got_error_from_errno("asprintf");
560 		path_got = NULL;
561 		goto done;
562 	}
563 
564 	err = got_object_open(&obj, repo, commit_id);
565 	if (err)
566 		return err;
567 
568 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
569 		err = got_error(GOT_ERR_OBJ_TYPE);
570 		goto done;
571 	}
572 
573 	/* Record our base commit. */
574 	err = got_object_id_str(&id_str, commit_id);
575 	if (err)
576 		goto done;
577 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
578 	if (err)
579 		goto done;
580 
581 	free(worktree->base_commit_id);
582 	worktree->base_commit_id = got_object_id_dup(commit_id);
583 	if (worktree->base_commit_id == NULL) {
584 		err = got_error_from_errno("got_object_id_dup");
585 		goto done;
586 	}
587 done:
588 	if (obj)
589 		got_object_close(obj);
590 	free(id_str);
591 	free(path_got);
592 	return err;
593 }
594 
595 static const struct got_error *
596 lock_worktree(struct got_worktree *worktree, int operation)
597 {
598 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
599 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
600 		    : got_error_from_errno2("flock",
601 		    got_worktree_get_root_path(worktree)));
602 	return NULL;
603 }
604 
605 static const struct got_error *
606 add_dir_on_disk(struct got_worktree *worktree, const char *path)
607 {
608 	const struct got_error *err = NULL;
609 	char *abspath;
610 
611 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
612 		return got_error_from_errno("asprintf");
613 
614 	err = got_path_mkdir(abspath);
615 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
616 		struct stat sb;
617 		err = NULL;
618 		if (lstat(abspath, &sb) == -1) {
619 			err = got_error_from_errno2("lstat", abspath);
620 		} else if (!S_ISDIR(sb.st_mode)) {
621 			/* TODO directory is obstructed; do something */
622 			err = got_error(GOT_ERR_FILE_OBSTRUCTED);
623 		}
624 	}
625 	free(abspath);
626 	return err;
627 }
628 
629 static const struct got_error *
630 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
631 {
632 	const struct got_error *err = NULL;
633 	uint8_t fbuf1[8192];
634 	uint8_t fbuf2[8192];
635 	size_t flen1 = 0, flen2 = 0;
636 
637 	*same = 1;
638 
639 	for (;;) {
640 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
641 		if (flen1 == 0 && ferror(f1)) {
642 			err = got_error_from_errno("fread");
643 			break;
644 		}
645 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
646 		if (flen2 == 0 && ferror(f2)) {
647 			err = got_error_from_errno("fread");
648 			break;
649 		}
650 		if (flen1 == 0) {
651 			if (flen2 != 0)
652 				*same = 0;
653 			break;
654 		} else if (flen2 == 0) {
655 			if (flen1 != 0)
656 				*same = 0;
657 			break;
658 		} else if (flen1 == flen2) {
659 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
660 				*same = 0;
661 				break;
662 			}
663 		} else {
664 			*same = 0;
665 			break;
666 		}
667 	}
668 
669 	return err;
670 }
671 
672 static const struct got_error *
673 check_files_equal(int *same, const char *f1_path, const char *f2_path)
674 {
675 	const struct got_error *err = NULL;
676 	struct stat sb;
677 	size_t size1, size2;
678 	FILE *f1 = NULL, *f2 = NULL;
679 
680 	*same = 1;
681 
682 	if (lstat(f1_path, &sb) != 0) {
683 		err = got_error_from_errno2("lstat", f1_path);
684 		goto done;
685 	}
686 	size1 = sb.st_size;
687 
688 	if (lstat(f2_path, &sb) != 0) {
689 		err = got_error_from_errno2("lstat", f2_path);
690 		goto done;
691 	}
692 	size2 = sb.st_size;
693 
694 	if (size1 != size2) {
695 		*same = 0;
696 		return NULL;
697 	}
698 
699 	f1 = fopen(f1_path, "r");
700 	if (f1 == NULL)
701 		return got_error_from_errno2("open", f1_path);
702 
703 	f2 = fopen(f2_path, "r");
704 	if (f2 == NULL) {
705 		err = got_error_from_errno2("open", f2_path);
706 		goto done;
707 	}
708 
709 	err = check_file_contents_equal(same, f1, f2);
710 done:
711 	if (f1 && fclose(f1) != 0 && err == NULL)
712 		err = got_error_from_errno("fclose");
713 	if (f2 && fclose(f2) != 0 && err == NULL)
714 		err = got_error_from_errno("fclose");
715 
716 	return err;
717 }
718 
719 /*
720  * Perform a 3-way merge where blob_orig acts as the common ancestor,
721  * blob_deriv acts as the first derived version, and the file on disk
722  * acts as the second derived version.
723  */
724 static const struct got_error *
725 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
726     struct got_blob_object *blob_orig, const char *ondisk_path,
727     const char *path, uint16_t st_mode, struct got_blob_object *blob_deriv,
728     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
729     void *progress_arg)
730 {
731 	const struct got_error *err = NULL;
732 	int merged_fd = -1;
733 	FILE *f_deriv = NULL, *f_orig = NULL;
734 	char *blob_deriv_path = NULL, *blob_orig_path = NULL;
735 	char *merged_path = NULL, *base_path = NULL;
736 	char *id_str = NULL;
737 	char *label1 = NULL;
738 	int overlapcnt = 0;
739 	char *parent;
740 
741 	*local_changes_subsumed = 0;
742 
743 	parent = dirname(ondisk_path);
744 	if (parent == NULL)
745 		return got_error_from_errno2("dirname", ondisk_path);
746 
747 	if (asprintf(&base_path, "%s/got-merged", parent) == -1)
748 		return got_error_from_errno("asprintf");
749 
750 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
751 	if (err)
752 		goto done;
753 
754 	free(base_path);
755 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
756 		err = got_error_from_errno("asprintf");
757 		base_path = NULL;
758 		goto done;
759 	}
760 
761 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path);
762 	if (err)
763 		goto done;
764 	err = got_object_blob_dump_to_file(NULL, NULL, f_deriv, blob_deriv);
765 	if (err)
766 		goto done;
767 
768 	free(base_path);
769 	if (asprintf(&base_path, "%s/got-merge-blob-orig", parent) == -1) {
770 		err = got_error_from_errno("asprintf");
771 		base_path = NULL;
772 		goto done;
773 	}
774 
775 	err = got_opentemp_named(&blob_orig_path, &f_orig, base_path);
776 	if (err)
777 		goto done;
778 	if (blob_orig) {
779 		err = got_object_blob_dump_to_file(NULL, NULL, f_orig,
780 		    blob_orig);
781 		if (err)
782 			goto done;
783 	} else {
784 		/*
785 		 * If the file has no blob, this is an "add vs add" conflict,
786 		 * and we simply use an empty ancestor file to make both files
787 		 * appear in the merged result in their entirety.
788 		 */
789 	}
790 
791 	err = got_object_id_str(&id_str, worktree->base_commit_id);
792 	if (err)
793 		goto done;
794 	if (asprintf(&label1, "commit %s", id_str) == -1) {
795 		err = got_error_from_errno("asprintf");
796 		goto done;
797 	}
798 
799 	err = got_merge_diff3(&overlapcnt, merged_fd, blob_deriv_path,
800 	    blob_orig_path, ondisk_path, label1, path);
801 	if (err)
802 		goto done;
803 
804 	(*progress_cb)(progress_arg,
805 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
806 
807 	if (fsync(merged_fd) != 0) {
808 		err = got_error_from_errno("fsync");
809 		goto done;
810 	}
811 
812 	/* Check if a clean merge has subsumed all local changes. */
813 	if (overlapcnt == 0) {
814 		err = check_files_equal(local_changes_subsumed, blob_deriv_path,
815 		    merged_path);
816 		if (err)
817 			goto done;
818 	}
819 
820 	if (chmod(merged_path, st_mode) != 0) {
821 		err = got_error_from_errno2("chmod", merged_path);
822 		goto done;
823 	}
824 
825 	if (rename(merged_path, ondisk_path) != 0) {
826 		err = got_error_from_errno3("rename", merged_path,
827 		    ondisk_path);
828 		unlink(merged_path);
829 		goto done;
830 	}
831 
832 done:
833 	if (merged_fd != -1 && close(merged_fd) != 0 && err == NULL)
834 		err = got_error_from_errno("close");
835 	if (f_deriv && fclose(f_deriv) != 0 && err == NULL)
836 		err = got_error_from_errno("fclose");
837 	if (f_orig && fclose(f_orig) != 0 && err == NULL)
838 		err = got_error_from_errno("fclose");
839 	free(merged_path);
840 	free(base_path);
841 	if (blob_deriv_path) {
842 		unlink(blob_deriv_path);
843 		free(blob_deriv_path);
844 	}
845 	if (blob_orig_path) {
846 		unlink(blob_orig_path);
847 		free(blob_orig_path);
848 	}
849 	free(id_str);
850 	free(label1);
851 	return err;
852 }
853 
854 static const struct got_error *
855 update_blob_fileindex_entry(struct got_worktree *worktree,
856     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
857     const char *ondisk_path, const char *path, struct got_blob_object *blob,
858     int update_timestamps)
859 {
860 	const struct got_error *err = NULL;
861 
862 	if (ie == NULL)
863 		ie = got_fileindex_entry_get(fileindex, path);
864 	if (ie)
865 		err = got_fileindex_entry_update(ie, ondisk_path,
866 		    blob->id.sha1, worktree->base_commit_id->sha1,
867 		    update_timestamps);
868 	else {
869 		struct got_fileindex_entry *new_ie;
870 		err = got_fileindex_entry_alloc(&new_ie, ondisk_path,
871 		    path, blob->id.sha1, worktree->base_commit_id->sha1);
872 		if (!err)
873 			err = got_fileindex_entry_add(fileindex, new_ie);
874 	}
875 	return err;
876 }
877 
878 static const struct got_error *
879 install_blob(struct got_worktree *worktree, const char *ondisk_path,
880    const char *path, uint16_t te_mode, uint16_t st_mode,
881    struct got_blob_object *blob, int restoring_missing_file,
882    int reverting_versioned_file, struct got_repository *repo,
883    got_worktree_checkout_cb progress_cb, void *progress_arg)
884 {
885 	const struct got_error *err = NULL;
886 	int fd = -1;
887 	size_t len, hdrlen;
888 	int update = 0;
889 	char *tmppath = NULL;
890 
891 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
892 	    GOT_DEFAULT_FILE_MODE);
893 	if (fd == -1) {
894 		if (errno == ENOENT) {
895 			char *parent = dirname(path);
896 			if (parent == NULL)
897 				return got_error_from_errno2("dirname", path);
898 			err = add_dir_on_disk(worktree, parent);
899 			if (err)
900 				return err;
901 			fd = open(ondisk_path,
902 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
903 			    GOT_DEFAULT_FILE_MODE);
904 			if (fd == -1)
905 				return got_error_from_errno2("open",
906 				    ondisk_path);
907 		} else if (errno == EEXIST) {
908 			if (!S_ISREG(st_mode)) {
909 				/* TODO file is obstructed; do something */
910 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
911 				goto done;
912 			} else {
913 				err = got_opentemp_named_fd(&tmppath, &fd,
914 				    ondisk_path);
915 				if (err)
916 					goto done;
917 				update = 1;
918 			}
919 		} else
920 			return got_error_from_errno2("open", ondisk_path);
921 	}
922 
923 	if (restoring_missing_file)
924 		(*progress_cb)(progress_arg, GOT_STATUS_MISSING, path);
925 	else if (reverting_versioned_file)
926 		(*progress_cb)(progress_arg, GOT_STATUS_REVERT, path);
927 	else
928 		(*progress_cb)(progress_arg,
929 		    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
930 
931 	hdrlen = got_object_blob_get_hdrlen(blob);
932 	do {
933 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
934 		err = got_object_blob_read_block(&len, blob);
935 		if (err)
936 			break;
937 		if (len > 0) {
938 			/* Skip blob object header first time around. */
939 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
940 			if (outlen == -1) {
941 				err = got_error_from_errno("write");
942 				goto done;
943 			} else if (outlen != len - hdrlen) {
944 				err = got_error(GOT_ERR_IO);
945 				goto done;
946 			}
947 			hdrlen = 0;
948 		}
949 	} while (len != 0);
950 
951 	if (fsync(fd) != 0) {
952 		err = got_error_from_errno("fsync");
953 		goto done;
954 	}
955 
956 	if (update) {
957 		if (rename(tmppath, ondisk_path) != 0) {
958 			err = got_error_from_errno3("rename", tmppath,
959 			    ondisk_path);
960 			unlink(tmppath);
961 			goto done;
962 		}
963 	}
964 
965 	if (te_mode & S_IXUSR) {
966 		if (chmod(ondisk_path, st_mode | S_IXUSR) == -1) {
967 			err = got_error_from_errno2("chmod", ondisk_path);
968 			goto done;
969 		}
970 	} else {
971 		if (chmod(ondisk_path, st_mode & ~S_IXUSR) == -1) {
972 			err = got_error_from_errno2("chmod", ondisk_path);
973 			goto done;
974 		}
975 	}
976 
977 done:
978 	if (fd != -1 && close(fd) != 0 && err == NULL)
979 		err = got_error_from_errno("close");
980 	free(tmppath);
981 	return err;
982 }
983 
984 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
985 static const struct got_error *
986 get_modified_file_content_status(unsigned char *status, FILE *f)
987 {
988 	const struct got_error *err = NULL;
989 	const char *markers[3] = {
990 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
991 		GOT_DIFF_CONFLICT_MARKER_SEP,
992 		GOT_DIFF_CONFLICT_MARKER_END
993 	};
994 	int i = 0;
995 	char *line;
996 	size_t len;
997 	const char delim[3] = {'\0', '\0', '\0'};
998 
999 	while (*status == GOT_STATUS_MODIFY) {
1000 		line = fparseln(f, &len, NULL, delim, 0);
1001 		if (line == NULL) {
1002 			if (feof(f))
1003 				break;
1004 			err = got_ferror(f, GOT_ERR_IO);
1005 			break;
1006 		}
1007 
1008 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1009 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1010 			    == 0)
1011 				*status = GOT_STATUS_CONFLICT;
1012 			else
1013 				i++;
1014 		}
1015 	}
1016 
1017 	return err;
1018 }
1019 
1020 static const struct got_error *
1021 get_file_status(unsigned char *status, struct stat *sb,
1022     struct got_fileindex_entry *ie, const char *abspath,
1023     struct got_repository *repo)
1024 {
1025 	const struct got_error *err = NULL;
1026 	struct got_object_id id;
1027 	size_t hdrlen;
1028 	FILE *f = NULL;
1029 	uint8_t fbuf[8192];
1030 	struct got_blob_object *blob = NULL;
1031 	size_t flen, blen;
1032 
1033 	*status = GOT_STATUS_NO_CHANGE;
1034 
1035 	if (lstat(abspath, sb) == -1) {
1036 		if (errno == ENOENT) {
1037 			if (ie) {
1038 				if (got_fileindex_entry_has_file_on_disk(ie))
1039 					*status = GOT_STATUS_MISSING;
1040 				else
1041 					*status = GOT_STATUS_DELETE;
1042 				sb->st_mode =
1043 				    ((ie->mode >> GOT_FILEIDX_MODE_PERMS_SHIFT)
1044 				    & (S_IRWXU | S_IRWXG | S_IRWXO));
1045 			} else
1046 				sb->st_mode = GOT_DEFAULT_FILE_MODE;
1047 			return NULL;
1048 		}
1049 		return got_error_from_errno2("lstat", abspath);
1050 	}
1051 
1052 	if (!S_ISREG(sb->st_mode)) {
1053 		*status = GOT_STATUS_OBSTRUCTED;
1054 		return NULL;
1055 	}
1056 
1057 	if (ie == NULL)
1058 		return NULL;
1059 
1060 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1061 		*status = GOT_STATUS_DELETE;
1062 		return NULL;
1063 	} else if (!got_fileindex_entry_has_blob(ie)) {
1064 		*status = GOT_STATUS_ADD;
1065 		return NULL;
1066 	}
1067 
1068 	if (ie->ctime_sec == sb->st_ctime &&
1069 	    ie->ctime_nsec == sb->st_ctimensec &&
1070 	    ie->mtime_sec == sb->st_mtime &&
1071 	    ie->mtime_sec == sb->st_mtime &&
1072 	    ie->mtime_nsec == sb->st_mtimensec &&
1073 	    ie->size == (sb->st_size & 0xffffffff))
1074 		return NULL;
1075 
1076 	memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1077 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1078 	if (err)
1079 		return err;
1080 
1081 	f = fopen(abspath, "r");
1082 	if (f == NULL) {
1083 		err = got_error_from_errno2("fopen", abspath);
1084 		goto done;
1085 	}
1086 	hdrlen = got_object_blob_get_hdrlen(blob);
1087 	for (;;) {
1088 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1089 		err = got_object_blob_read_block(&blen, blob);
1090 		if (err)
1091 			goto done;
1092 		/* Skip length of blob object header first time around. */
1093 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1094 		if (flen == 0 && ferror(f)) {
1095 			err = got_error_from_errno("fread");
1096 			goto done;
1097 		}
1098 		if (blen == 0) {
1099 			if (flen != 0)
1100 				*status = GOT_STATUS_MODIFY;
1101 			break;
1102 		} else if (flen == 0) {
1103 			if (blen != 0)
1104 				*status = GOT_STATUS_MODIFY;
1105 			break;
1106 		} else if (blen - hdrlen == flen) {
1107 			/* Skip blob object header first time around. */
1108 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1109 				*status = GOT_STATUS_MODIFY;
1110 				break;
1111 			}
1112 		} else {
1113 			*status = GOT_STATUS_MODIFY;
1114 			break;
1115 		}
1116 		hdrlen = 0;
1117 	}
1118 
1119 	if (*status == GOT_STATUS_MODIFY) {
1120 		rewind(f);
1121 		err = get_modified_file_content_status(status, f);
1122 	}
1123 done:
1124 	if (blob)
1125 		got_object_blob_close(blob);
1126 	if (f)
1127 		fclose(f);
1128 	return err;
1129 }
1130 
1131 static const struct got_error *
1132 update_blob(struct got_worktree *worktree,
1133     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1134     struct got_tree_entry *te, const char *path,
1135     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1136     void *progress_arg)
1137 {
1138 	const struct got_error *err = NULL;
1139 	struct got_blob_object *blob = NULL;
1140 	char *ondisk_path;
1141 	unsigned char status = GOT_STATUS_NO_CHANGE;
1142 	struct stat sb;
1143 
1144 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1145 		return got_error_from_errno("asprintf");
1146 
1147 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1148 	if (err)
1149 		goto done;
1150 
1151 	if (status == GOT_STATUS_OBSTRUCTED) {
1152 		(*progress_cb)(progress_arg, status, path);
1153 		goto done;
1154 	}
1155 
1156 	if (ie && status != GOT_STATUS_MISSING) {
1157 		if (got_fileindex_entry_has_commit(ie) &&
1158 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1159 		    SHA1_DIGEST_LENGTH) == 0) {
1160 			(*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1161 			    path);
1162 			goto done;
1163 		}
1164 		if (got_fileindex_entry_has_blob(ie) &&
1165 		    memcmp(ie->blob_sha1, te->id->sha1,
1166 		    SHA1_DIGEST_LENGTH) == 0)
1167 			goto done;
1168 	}
1169 
1170 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1171 	if (err)
1172 		goto done;
1173 
1174 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1175 		int update_timestamps;
1176 		struct got_blob_object *blob2 = NULL;
1177 		if (got_fileindex_entry_has_blob(ie)) {
1178 			struct got_object_id id2;
1179 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1180 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
1181 			if (err)
1182 				goto done;
1183 		}
1184 		err = merge_blob(&update_timestamps, worktree, blob2,
1185 		    ondisk_path, path, sb.st_mode, blob, repo,
1186 		    progress_cb, progress_arg);
1187 		if (blob2)
1188 			got_object_blob_close(blob2);
1189 		/*
1190 		 * Do not update timestamps of files with local changes.
1191 		 * Otherwise, a future status walk would treat them as
1192 		 * unmodified files again.
1193 		 */
1194 		err = got_fileindex_entry_update(ie, ondisk_path,
1195 		    blob->id.sha1, worktree->base_commit_id->sha1,
1196 		    update_timestamps);
1197 	} else if (status == GOT_STATUS_DELETE) {
1198 		(*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1199 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1200 		    ondisk_path, path, blob, 0);
1201 		if (err)
1202 			goto done;
1203 	} else {
1204 		err = install_blob(worktree, ondisk_path, path, te->mode,
1205 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1206 		    repo, progress_cb, progress_arg);
1207 		if (err)
1208 			goto done;
1209 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1210 		    ondisk_path, path, blob, 1);
1211 		if (err)
1212 			goto done;
1213 	}
1214 	got_object_blob_close(blob);
1215 done:
1216 	free(ondisk_path);
1217 	return err;
1218 }
1219 
1220 static const struct got_error *
1221 remove_ondisk_file(const char *root_path, const char *path)
1222 {
1223 	const struct got_error *err = NULL;
1224 	char *ondisk_path = NULL;
1225 
1226 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1227 		return got_error_from_errno("asprintf");
1228 
1229 	if (unlink(ondisk_path) == -1) {
1230 		if (errno != ENOENT)
1231 			err = got_error_from_errno2("unlink", ondisk_path);
1232 	} else {
1233 		char *parent = dirname(ondisk_path);
1234 		while (parent && strcmp(parent, root_path) != 0) {
1235 			if (rmdir(parent) == -1) {
1236 				if (errno != ENOTEMPTY)
1237 					err = got_error_from_errno2("rmdir",
1238 					    parent);
1239 				break;
1240 			}
1241 			parent = dirname(parent);
1242 		}
1243 	}
1244 	free(ondisk_path);
1245 	return err;
1246 }
1247 
1248 static const struct got_error *
1249 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1250     struct got_fileindex_entry *ie, struct got_repository *repo,
1251     got_worktree_checkout_cb progress_cb, void *progress_arg)
1252 {
1253 	const struct got_error *err = NULL;
1254 	unsigned char status;
1255 	struct stat sb;
1256 	char *ondisk_path;
1257 
1258 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1259 	    == -1)
1260 		return got_error_from_errno("asprintf");
1261 
1262 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1263 	if (err)
1264 		return err;
1265 
1266 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1267 	    status == GOT_STATUS_ADD) {
1268 		(*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1269 		/*
1270 		 * Preserve the working file and change the deleted blob's
1271 		 * entry into a schedule-add entry.
1272 		 */
1273 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1274 		    0);
1275 		if (err)
1276 			return err;
1277 	} else {
1278 		(*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1279 		if (status == GOT_STATUS_NO_CHANGE) {
1280 			err = remove_ondisk_file(worktree->root_path, ie->path);
1281 			if (err)
1282 				return err;
1283 		}
1284 		got_fileindex_entry_remove(fileindex, ie);
1285 	}
1286 
1287 	return err;
1288 }
1289 
1290 struct diff_cb_arg {
1291     struct got_fileindex *fileindex;
1292     struct got_worktree *worktree;
1293     struct got_repository *repo;
1294     got_worktree_checkout_cb progress_cb;
1295     void *progress_arg;
1296     got_worktree_cancel_cb cancel_cb;
1297     void *cancel_arg;
1298 };
1299 
1300 static const struct got_error *
1301 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1302     struct got_tree_entry *te, const char *parent_path)
1303 {
1304 	struct diff_cb_arg *a = arg;
1305 
1306 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1307 		return got_error(GOT_ERR_CANCELLED);
1308 
1309 	return update_blob(a->worktree, a->fileindex, ie, te,
1310 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1311 }
1312 
1313 static const struct got_error *
1314 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1315 {
1316 	struct diff_cb_arg *a = arg;
1317 
1318 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1319 		return got_error(GOT_ERR_CANCELLED);
1320 
1321 	return delete_blob(a->worktree, a->fileindex, ie,
1322 	    a->repo, a->progress_cb, a->progress_arg);
1323 }
1324 
1325 static const struct got_error *
1326 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1327 {
1328 	struct diff_cb_arg *a = arg;
1329 	const struct got_error *err;
1330 	char *path;
1331 
1332 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1333 		return got_error(GOT_ERR_CANCELLED);
1334 
1335 	if (asprintf(&path, "%s%s%s", parent_path,
1336 	    parent_path[0] ? "/" : "", te->name)
1337 	    == -1)
1338 		return got_error_from_errno("asprintf");
1339 
1340 	if (S_ISDIR(te->mode))
1341 		err = add_dir_on_disk(a->worktree, path);
1342 	else
1343 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1344 		    a->repo, a->progress_cb, a->progress_arg);
1345 
1346 	free(path);
1347 	return err;
1348 }
1349 
1350 const struct got_error *
1351 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1352 {
1353 	const struct got_error *err = NULL;
1354 	char *uuidstr = NULL;
1355 	uint32_t uuid_status;
1356 
1357 	*refname = NULL;
1358 
1359 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1360 	if (uuid_status != uuid_s_ok)
1361 		return got_error_uuid(uuid_status);
1362 
1363 	if (asprintf(refname, "%s-%s", GOT_WORKTREE_BASE_REF_PREFIX, uuidstr)
1364 	    == -1) {
1365 		err = got_error_from_errno("asprintf");
1366 		*refname = NULL;
1367 	}
1368 	free(uuidstr);
1369 	return err;
1370 }
1371 
1372 /*
1373  * Prevent Git's garbage collector from deleting our base commit by
1374  * setting a reference to our base commit's ID.
1375  */
1376 static const struct got_error *
1377 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1378 {
1379 	const struct got_error *err = NULL;
1380 	struct got_reference *ref = NULL;
1381 	char *refname;
1382 
1383 	err = got_worktree_get_base_ref_name(&refname, worktree);
1384 	if (err)
1385 		return err;
1386 
1387 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1388 	if (err)
1389 		goto done;
1390 
1391 	err = got_ref_write(ref, repo);
1392 done:
1393 	free(refname);
1394 	if (ref)
1395 		got_ref_close(ref);
1396 	return err;
1397 }
1398 
1399 static const struct got_error *
1400 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1401    struct got_worktree *worktree)
1402 {
1403 	const struct got_error *err = NULL;
1404 	FILE *index = NULL;
1405 
1406 	*fileindex_path = NULL;
1407 	*fileindex = got_fileindex_alloc();
1408 	if (*fileindex == NULL)
1409 		return got_error_from_errno("got_fileindex_alloc");
1410 
1411 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1412 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1413 		err = got_error_from_errno("asprintf");
1414 		*fileindex_path = NULL;
1415 		goto done;
1416 	}
1417 
1418 	index = fopen(*fileindex_path, "rb");
1419 	if (index == NULL) {
1420 		if (errno != ENOENT)
1421 			err = got_error_from_errno2("fopen", *fileindex_path);
1422 	} else {
1423 		err = got_fileindex_read(*fileindex, index);
1424 		if (fclose(index) != 0 && err == NULL)
1425 			err = got_error_from_errno("fclose");
1426 	}
1427 done:
1428 	if (err) {
1429 		free(*fileindex_path);
1430 		*fileindex_path = NULL;
1431 		free(*fileindex);
1432 		*fileindex = NULL;
1433 	}
1434 	return err;
1435 }
1436 
1437 struct bump_base_commit_id_arg {
1438 	struct got_object_id *base_commit_id;
1439 	const char *path;
1440 	size_t path_len;
1441 	const char *entry_name;
1442 	got_worktree_checkout_cb progress_cb;
1443 	void *progress_arg;
1444 };
1445 
1446 /* Bump base commit ID of all files within an updated part of the work tree. */
1447 static const struct got_error *
1448 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
1449 {
1450 	struct bump_base_commit_id_arg *a = arg;
1451 
1452 	if (a->entry_name) {
1453 		if (strcmp(ie->path, a->path) != 0)
1454 			return NULL;
1455 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
1456 		return NULL;
1457 
1458 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
1459 	    SHA1_DIGEST_LENGTH) == 0)
1460 		return NULL;
1461 
1462 	(*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE, ie->path);
1463 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
1464 	return NULL;
1465 }
1466 
1467 static const struct got_error *
1468 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
1469 {
1470 	const struct got_error *err = NULL;
1471 	char *new_fileindex_path = NULL;
1472 	FILE *new_index = NULL;
1473 
1474 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1475 	    fileindex_path);
1476 	if (err)
1477 		goto done;
1478 
1479 	err = got_fileindex_write(fileindex, new_index);
1480 	if (err)
1481 		goto done;
1482 
1483 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1484 		err = got_error_from_errno3("rename", new_fileindex_path,
1485 		    fileindex_path);
1486 		unlink(new_fileindex_path);
1487 	}
1488 done:
1489 	if (new_index)
1490 		fclose(new_index);
1491 	free(new_fileindex_path);
1492 	return err;
1493 }
1494 
1495 const struct got_error *
1496 got_worktree_checkout_files(struct got_worktree *worktree, const char *path,
1497     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1498     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1499 {
1500 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1501 	struct got_commit_object *commit = NULL;
1502 	struct got_object_id *tree_id = NULL;
1503 	struct got_tree_object *tree = NULL;
1504 	struct got_fileindex *fileindex = NULL;
1505 	char *fileindex_path = NULL;
1506 	struct got_fileindex_diff_tree_cb diff_cb;
1507 	struct diff_cb_arg arg;
1508 	char *relpath = NULL, *entry_name = NULL;
1509 	struct bump_base_commit_id_arg bbc_arg;
1510 
1511 	err = lock_worktree(worktree, LOCK_EX);
1512 	if (err)
1513 		return err;
1514 
1515 	/*
1516 	 * Read the file index.
1517 	 * Checking out files is supposed to be an idempotent operation.
1518 	 * If the on-disk file index is incomplete we will try to complete it.
1519 	 */
1520 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1521 	if (err)
1522 		goto done;
1523 
1524 	err = ref_base_commit(worktree, repo);
1525 	if (err)
1526 		goto done;
1527 
1528 	err = got_object_open_as_commit(&commit, repo,
1529 	   worktree->base_commit_id);
1530 	if (err)
1531 		goto done;
1532 
1533 	if (path[0]) {
1534 		char *tree_path;
1535 		int obj_type;
1536 		relpath = strdup(path);
1537 		if (relpath == NULL) {
1538 			err = got_error_from_errno("strdup");
1539 			goto done;
1540 		}
1541 		if (asprintf(&tree_path, "%s%s%s", worktree->path_prefix,
1542 		    got_path_is_root_dir(worktree->path_prefix) ? "" : "/",
1543 		    path) == -1) {
1544 			err = got_error_from_errno("asprintf");
1545 			goto done;
1546 		}
1547 		err = got_object_id_by_path(&tree_id, repo,
1548 		    worktree->base_commit_id, tree_path);
1549 		free(tree_path);
1550 		if (err)
1551 			goto done;
1552 		err = got_object_get_type(&obj_type, repo, tree_id);
1553 		if (err)
1554 			goto done;
1555 		if (obj_type == GOT_OBJ_TYPE_BLOB) {
1556 			/* Split provided path into parent dir + entry name. */
1557 			if (strchr(path, '/')  == NULL) {
1558 				relpath = strdup("");
1559 				if (relpath == NULL) {
1560 					err = got_error_from_errno("strdup");
1561 					goto done;
1562 				}
1563 				tree_path = strdup(worktree->path_prefix);
1564 				if (tree_path == NULL) {
1565 					err = got_error_from_errno("strdup");
1566 					goto done;
1567 				}
1568 			} else {
1569 				err = got_path_dirname(&relpath, path);
1570 				if (err)
1571 					goto done;
1572 				if (asprintf(&tree_path, "%s%s%s",
1573 				    worktree->path_prefix,
1574 				    got_path_is_root_dir(
1575 				    worktree->path_prefix) ? "" : "/",
1576 				    relpath) == -1) {
1577 					err = got_error_from_errno("asprintf");
1578 					goto done;
1579 				}
1580 			}
1581 			err = got_object_id_by_path(&tree_id, repo,
1582 			    worktree->base_commit_id, tree_path);
1583 			free(tree_path);
1584 			if (err)
1585 				goto done;
1586 			entry_name = basename(path);
1587 			if (entry_name == NULL) {
1588 				err = got_error_from_errno2("basename", path);
1589 				goto done;
1590 			}
1591 		}
1592 	} else {
1593 		relpath = strdup("");
1594 		if (relpath == NULL) {
1595 			err = got_error_from_errno("strdup");
1596 			goto done;
1597 		}
1598 		err = got_object_id_by_path(&tree_id, repo,
1599 		    worktree->base_commit_id, worktree->path_prefix);
1600 		if (err)
1601 			goto done;
1602 	}
1603 
1604 	err = got_object_open_as_tree(&tree, repo, tree_id);
1605 	if (err)
1606 		goto done;
1607 
1608 	if (entry_name &&
1609 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1610 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1611 		goto done;
1612 	}
1613 
1614 	diff_cb.diff_old_new = diff_old_new;
1615 	diff_cb.diff_old = diff_old;
1616 	diff_cb.diff_new = diff_new;
1617 	arg.fileindex = fileindex;
1618 	arg.worktree = worktree;
1619 	arg.repo = repo;
1620 	arg.progress_cb = progress_cb;
1621 	arg.progress_arg = progress_arg;
1622 	arg.cancel_cb = cancel_cb;
1623 	arg.cancel_arg = cancel_arg;
1624 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
1625 	    entry_name, repo, &diff_cb, &arg);
1626 	if (err)
1627 		goto sync;
1628 
1629 	bbc_arg.base_commit_id = worktree->base_commit_id;
1630 	bbc_arg.entry_name = entry_name;
1631 	bbc_arg.path = path;
1632 	bbc_arg.path_len = strlen(path);
1633 	bbc_arg.progress_cb = progress_cb;
1634 	bbc_arg.progress_arg = progress_arg;
1635 	err = got_fileindex_for_each_entry_safe(fileindex,
1636 	    bump_base_commit_id, &bbc_arg);
1637 sync:
1638 	sync_err = sync_fileindex(fileindex, fileindex_path);
1639 	if (sync_err && err == NULL)
1640 		err = sync_err;
1641 done:
1642 	free(fileindex_path);
1643 	free(relpath);
1644 	if (tree)
1645 		got_object_tree_close(tree);
1646 	if (commit)
1647 		got_object_commit_close(commit);
1648 	got_fileindex_free(fileindex);
1649 	unlockerr = lock_worktree(worktree, LOCK_SH);
1650 	if (unlockerr && err == NULL)
1651 		err = unlockerr;
1652 	return err;
1653 }
1654 
1655 struct merge_file_cb_arg {
1656     struct got_worktree *worktree;
1657     struct got_fileindex *fileindex;
1658     got_worktree_checkout_cb progress_cb;
1659     void *progress_arg;
1660     got_worktree_cancel_cb cancel_cb;
1661     void *cancel_arg;
1662 };
1663 
1664 static const struct got_error *
1665 merge_file_cb(void *arg, struct got_blob_object *blob1,
1666     struct got_blob_object *blob2, struct got_object_id *id1,
1667     struct got_object_id *id2, const char *path1, const char *path2,
1668     struct got_repository *repo)
1669 {
1670 	static const struct got_error *err = NULL;
1671 	struct merge_file_cb_arg *a = arg;
1672 	struct got_fileindex_entry *ie;
1673 	char *ondisk_path = NULL;
1674 	struct stat sb;
1675 	unsigned char status;
1676 	int local_changes_subsumed;
1677 
1678 	if (blob1 && blob2) {
1679 		ie = got_fileindex_entry_get(a->fileindex, path2);
1680 		if (ie == NULL) {
1681 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_MISSING,
1682 			    path2);
1683 			return NULL;
1684 		}
1685 
1686 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1687 		    path2) == -1)
1688 			return got_error_from_errno("asprintf");
1689 
1690 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1691 		if (err)
1692 			goto done;
1693 
1694 		if (status == GOT_STATUS_DELETE) {
1695 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_MERGE,
1696 			    path2);
1697 			goto done;
1698 		}
1699 		if (status != GOT_STATUS_NO_CHANGE &&
1700 		    status != GOT_STATUS_MODIFY &&
1701 		    status != GOT_STATUS_CONFLICT &&
1702 		    status != GOT_STATUS_ADD) {
1703 			(*a->progress_cb)(a->progress_arg, status, path2);
1704 			goto done;
1705 		}
1706 
1707 		err = merge_blob(&local_changes_subsumed, a->worktree, blob1,
1708 		    ondisk_path, path2, sb.st_mode, blob2, repo,
1709 		    a->progress_cb, a->progress_arg);
1710 	} else if (blob1) {
1711 		ie = got_fileindex_entry_get(a->fileindex, path1);
1712 		if (ie == NULL) {
1713 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_MISSING,
1714 			    path2);
1715 			return NULL;
1716 		}
1717 
1718 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1719 		    path1) == -1)
1720 			return got_error_from_errno("asprintf");
1721 
1722 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1723 		if (err)
1724 			goto done;
1725 
1726 		switch (status) {
1727 		case GOT_STATUS_NO_CHANGE:
1728 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_DELETE,
1729 			    path1);
1730 			err = remove_ondisk_file(a->worktree->root_path, path1);
1731 			if (err)
1732 				goto done;
1733 			if (ie)
1734 				got_fileindex_entry_mark_deleted_from_disk(ie);
1735 			break;
1736 		case GOT_STATUS_DELETE:
1737 		case GOT_STATUS_MISSING:
1738 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_DELETE,
1739 			    path1);
1740 			if (ie)
1741 				got_fileindex_entry_mark_deleted_from_disk(ie);
1742 			break;
1743 		case GOT_STATUS_ADD:
1744 		case GOT_STATUS_MODIFY:
1745 		case GOT_STATUS_CONFLICT:
1746 			(*a->progress_cb)(a->progress_arg,
1747 			    GOT_STATUS_CANNOT_DELETE, path1);
1748 			break;
1749 		case GOT_STATUS_OBSTRUCTED:
1750 			(*a->progress_cb)(a->progress_arg, status, path1);
1751 			break;
1752 		default:
1753 			break;
1754 		}
1755 	} else if (blob2) {
1756 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1757 		    path2) == -1)
1758 			return got_error_from_errno("asprintf");
1759 		ie = got_fileindex_entry_get(a->fileindex, path2);
1760 		if (ie) {
1761 			err = get_file_status(&status, &sb, ie, ondisk_path,
1762 			    repo);
1763 			if (err)
1764 				goto done;
1765 			if (status != GOT_STATUS_NO_CHANGE &&
1766 			    status != GOT_STATUS_MODIFY &&
1767 			    status != GOT_STATUS_CONFLICT &&
1768 			    status != GOT_STATUS_ADD) {
1769 				(*a->progress_cb)(a->progress_arg, status,
1770 				    path2);
1771 				goto done;
1772 			}
1773 			err = merge_blob(&local_changes_subsumed, a->worktree,
1774 			    NULL, ondisk_path, path2, sb.st_mode, blob2, repo,
1775 			    a->progress_cb, a->progress_arg);
1776 			if (status == GOT_STATUS_DELETE) {
1777 				err = update_blob_fileindex_entry(a->worktree,
1778 				    a->fileindex, ie, ondisk_path, ie->path,
1779 				    blob2, 0);
1780 				if (err)
1781 					goto done;
1782 			}
1783 		} else {
1784 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
1785 			err = install_blob(a->worktree, ondisk_path, path2,
1786 			    /* XXX get this from parent tree! */
1787 			    GOT_DEFAULT_FILE_MODE,
1788 			    sb.st_mode, blob2, 0, 0, repo,
1789 			    a->progress_cb, a->progress_arg);
1790 			if (err)
1791 				goto done;
1792 			err = got_fileindex_entry_alloc(&ie,
1793 			    ondisk_path, path2, NULL, NULL);
1794 			if (err)
1795 				goto done;
1796 			err = got_fileindex_entry_add(a->fileindex, ie);
1797 			if (err) {
1798 				got_fileindex_entry_free(ie);
1799 				goto done;
1800 			}
1801 		}
1802 	}
1803 done:
1804 	free(ondisk_path);
1805 	return err;
1806 }
1807 
1808 struct check_merge_ok_arg {
1809 	struct got_worktree *worktree;
1810 	struct got_repository *repo;
1811 };
1812 
1813 static const struct got_error *
1814 check_merge_ok(void *arg, struct got_fileindex_entry *ie)
1815 {
1816 	const struct got_error *err = NULL;
1817 	struct check_merge_ok_arg *a = arg;
1818 	unsigned char status;
1819 	struct stat sb;
1820 	char *ondisk_path;
1821 
1822 	/* Reject merges into a work tree with mixed base commits. */
1823 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
1824 	    SHA1_DIGEST_LENGTH))
1825 		return got_error(GOT_ERR_MIXED_COMMITS);
1826 
1827 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
1828 	    == -1)
1829 		return got_error_from_errno("asprintf");
1830 
1831 	/* Reject merges into a work tree with conflicted files. */
1832 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
1833 	if (err)
1834 		return err;
1835 	if (status == GOT_STATUS_CONFLICT)
1836 		return got_error(GOT_ERR_CONFLICTS);
1837 
1838 	return NULL;
1839 }
1840 
1841 const struct got_error *
1842 got_worktree_merge_files(struct got_worktree *worktree,
1843     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
1844     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1845     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1846 {
1847 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1848 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
1849 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
1850 	struct merge_file_cb_arg arg;
1851 	char *fileindex_path = NULL;
1852 	struct got_fileindex *fileindex = NULL;
1853 	struct check_merge_ok_arg mok_arg;
1854 
1855 	err = lock_worktree(worktree, LOCK_EX);
1856 	if (err)
1857 		return err;
1858 
1859 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1860 	if (err)
1861 		goto done;
1862 
1863 	mok_arg.worktree = worktree;
1864 	mok_arg.repo = repo;
1865 	err = got_fileindex_for_each_entry_safe(fileindex, check_merge_ok,
1866 	    &mok_arg);
1867 	if (err)
1868 		goto done;
1869 
1870 	if (commit_id1) {
1871 		err = got_object_id_by_path(&tree_id1, repo, commit_id1,
1872 		    worktree->path_prefix);
1873 		if (err)
1874 			goto done;
1875 
1876 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
1877 		if (err)
1878 			goto done;
1879 	}
1880 
1881 	err = got_object_id_by_path(&tree_id2, repo, commit_id2,
1882 	    worktree->path_prefix);
1883 	if (err)
1884 		goto done;
1885 
1886 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
1887 	if (err)
1888 		goto done;
1889 
1890 	arg.worktree = worktree;
1891 	arg.fileindex = fileindex;
1892 	arg.progress_cb = progress_cb;
1893 	arg.progress_arg = progress_arg;
1894 	arg.cancel_cb = cancel_cb;
1895 	arg.cancel_arg = cancel_arg;
1896 	err = got_diff_tree(tree1, tree2, "", "", repo, merge_file_cb, &arg);
1897 	sync_err = sync_fileindex(fileindex, fileindex_path);
1898 	if (sync_err && err == NULL)
1899 		err = sync_err;
1900 done:
1901 	got_fileindex_free(fileindex);
1902 	if (tree1)
1903 		got_object_tree_close(tree1);
1904 	if (tree2)
1905 		got_object_tree_close(tree2);
1906 
1907 	unlockerr = lock_worktree(worktree, LOCK_SH);
1908 	if (unlockerr && err == NULL)
1909 		err = unlockerr;
1910 	return err;
1911 }
1912 
1913 struct diff_dir_cb_arg {
1914     struct got_fileindex *fileindex;
1915     struct got_worktree *worktree;
1916     const char *status_path;
1917     size_t status_path_len;
1918     struct got_repository *repo;
1919     got_worktree_status_cb status_cb;
1920     void *status_arg;
1921     got_worktree_cancel_cb cancel_cb;
1922     void *cancel_arg;
1923 };
1924 
1925 static const struct got_error *
1926 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
1927     got_worktree_status_cb status_cb, void *status_arg,
1928     struct got_repository *repo)
1929 {
1930 	const struct got_error *err = NULL;
1931 	unsigned char status = GOT_STATUS_NO_CHANGE;
1932 	struct stat sb;
1933 	struct got_object_id blob_id, commit_id;
1934 
1935 	err = get_file_status(&status, &sb, ie, abspath, repo);
1936 	if (err == NULL && status != GOT_STATUS_NO_CHANGE) {
1937 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1938 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
1939 		err = (*status_cb)(status_arg, status, ie->path, &blob_id,
1940 		    &commit_id);
1941 	}
1942 	return err;
1943 }
1944 
1945 static const struct got_error *
1946 status_old_new(void *arg, struct got_fileindex_entry *ie,
1947     struct dirent *de, const char *parent_path)
1948 {
1949 	const struct got_error *err = NULL;
1950 	struct diff_dir_cb_arg *a = arg;
1951 	char *abspath;
1952 
1953 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1954 		return got_error(GOT_ERR_CANCELLED);
1955 
1956 	if (got_path_cmp(parent_path, a->status_path) != 0 &&
1957 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
1958 		return NULL;
1959 
1960 	if (parent_path[0]) {
1961 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
1962 		    parent_path, de->d_name) == -1)
1963 			return got_error_from_errno("asprintf");
1964 	} else {
1965 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
1966 		    de->d_name) == -1)
1967 			return got_error_from_errno("asprintf");
1968 	}
1969 
1970 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
1971 	    a->repo);
1972 	free(abspath);
1973 	return err;
1974 }
1975 
1976 static const struct got_error *
1977 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1978 {
1979 	struct diff_dir_cb_arg *a = arg;
1980 	struct got_object_id blob_id, commit_id;
1981 	unsigned char status;
1982 
1983 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1984 		return got_error(GOT_ERR_CANCELLED);
1985 
1986 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
1987 		return NULL;
1988 
1989 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1990 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
1991 	if (got_fileindex_entry_has_file_on_disk(ie))
1992 		status = GOT_STATUS_MISSING;
1993 	else
1994 		status = GOT_STATUS_DELETE;
1995 	return (*a->status_cb)(a->status_arg, status, ie->path, &blob_id,
1996 	    &commit_id);
1997 }
1998 
1999 static const struct got_error *
2000 status_new(void *arg, struct dirent *de, const char *parent_path)
2001 {
2002 	const struct got_error *err = NULL;
2003 	struct diff_dir_cb_arg *a = arg;
2004 	char *path = NULL;
2005 
2006 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2007 		return got_error(GOT_ERR_CANCELLED);
2008 
2009 	if (de->d_type == DT_DIR)
2010 		return NULL;
2011 
2012 	/* XXX ignore symlinks for now */
2013 	if (de->d_type == DT_LNK)
2014 		return NULL;
2015 
2016 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
2017 		return NULL;
2018 
2019 	if (parent_path[0]) {
2020 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
2021 			return got_error_from_errno("asprintf");
2022 	} else {
2023 		path = de->d_name;
2024 	}
2025 
2026 	err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED, path,
2027 	    NULL, NULL);
2028 	if (parent_path[0])
2029 		free(path);
2030 	return err;
2031 }
2032 
2033 const struct got_error *
2034 got_worktree_status(struct got_worktree *worktree, const char *path,
2035     struct got_repository *repo, got_worktree_status_cb status_cb,
2036     void *status_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2037 {
2038 	const struct got_error *err = NULL;
2039 	DIR *workdir = NULL;
2040 	char *fileindex_path = NULL;
2041 	struct got_fileindex *fileindex = NULL;
2042 	FILE *index = NULL;
2043 	struct got_fileindex_diff_dir_cb fdiff_cb;
2044 	struct diff_dir_cb_arg arg;
2045 	char *ondisk_path = NULL;
2046 
2047 	fileindex = got_fileindex_alloc();
2048 	if (fileindex == NULL) {
2049 		err = got_error_from_errno("got_fileindex_alloc");
2050 		goto done;
2051 	}
2052 
2053 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2054 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2055 		err = got_error_from_errno("asprintf");
2056 		fileindex_path = NULL;
2057 		goto done;
2058 	}
2059 
2060 	index = fopen(fileindex_path, "rb");
2061 	if (index == NULL) {
2062 		if (errno != ENOENT) {
2063 			err = got_error_from_errno2("fopen", fileindex_path);
2064 			goto done;
2065 		}
2066 	} else {
2067 		err = got_fileindex_read(fileindex, index);
2068 		fclose(index);
2069 		if (err)
2070 			goto done;
2071 	}
2072 
2073 	if (asprintf(&ondisk_path, "%s%s%s",
2074 	    worktree->root_path, path[0] ? "/" : "", path) == -1) {
2075 		err = got_error_from_errno("asprintf");
2076 		goto done;
2077 	}
2078 	workdir = opendir(ondisk_path);
2079 	if (workdir == NULL) {
2080 		if (errno == ENOTDIR || errno == ENOENT) {
2081 			struct got_fileindex_entry *ie;
2082 			ie = got_fileindex_entry_get(fileindex, path);
2083 			if (ie == NULL) {
2084 				err = got_error(GOT_ERR_BAD_PATH);
2085 				goto done;
2086 			}
2087 			err = report_file_status(ie, ondisk_path,
2088 			    status_cb, status_arg, repo);
2089 			goto done;
2090 		} else {
2091 			err = got_error_from_errno2("opendir", ondisk_path);
2092 			goto done;
2093 		}
2094 	}
2095 	fdiff_cb.diff_old_new = status_old_new;
2096 	fdiff_cb.diff_old = status_old;
2097 	fdiff_cb.diff_new = status_new;
2098 	arg.fileindex = fileindex;
2099 	arg.worktree = worktree;
2100 	arg.status_path = path;
2101 	arg.status_path_len = strlen(path);
2102 	arg.repo = repo;
2103 	arg.status_cb = status_cb;
2104 	arg.status_arg = status_arg;
2105 	arg.cancel_cb = cancel_cb;
2106 	arg.cancel_arg = cancel_arg;
2107 	err = got_fileindex_diff_dir(fileindex, workdir, worktree->root_path,
2108 	    path, repo, &fdiff_cb, &arg);
2109 done:
2110 	if (workdir)
2111 		closedir(workdir);
2112 	free(ondisk_path);
2113 	free(fileindex_path);
2114 	got_fileindex_free(fileindex);
2115 	return err;
2116 }
2117 
2118 const struct got_error *
2119 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
2120     const char *arg)
2121 {
2122 	const struct got_error *err = NULL;
2123 	char *resolved, *path = NULL;
2124 	size_t len;
2125 
2126 	*wt_path = NULL;
2127 
2128 	resolved = realpath(arg, NULL);
2129 	if (resolved == NULL)
2130 		return got_error_from_errno2("realpath", arg);
2131 
2132 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
2133 	    strlen(got_worktree_get_root_path(worktree)))) {
2134 		err = got_error(GOT_ERR_BAD_PATH);
2135 		goto done;
2136 	}
2137 
2138 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
2139 		err = got_path_skip_common_ancestor(&path,
2140 		    got_worktree_get_root_path(worktree), resolved);
2141 		if (err)
2142 			goto done;
2143 	} else {
2144 		path = strdup("");
2145 		if (path == NULL) {
2146 			err = got_error_from_errno("strdup");
2147 			goto done;
2148 		}
2149 	}
2150 
2151 	/* XXX status walk can't deal with trailing slash! */
2152 	len = strlen(path);
2153 	while (path[len - 1] == '/') {
2154 		path[len - 1] = '\0';
2155 		len--;
2156 	}
2157 done:
2158 	free(resolved);
2159 	if (err == NULL)
2160 		*wt_path = path;
2161 	else
2162 		free(path);
2163 	return err;
2164 }
2165 
2166 static const struct got_error *
2167 schedule_addition(const char *ondisk_path, struct got_fileindex *fileindex,
2168     const char *relpath, got_worktree_status_cb status_cb, void *status_arg,
2169     struct got_repository *repo)
2170 {
2171 	const struct got_error *err = NULL;
2172 	struct got_fileindex_entry *ie;
2173 
2174 	/* Re-adding an existing entry is a no-op. */
2175 	if (got_fileindex_entry_get(fileindex, relpath) != NULL)
2176 		return NULL;
2177 
2178 	err = got_fileindex_entry_alloc(&ie, ondisk_path, relpath, NULL, NULL);
2179 	if (err)
2180 		return err;
2181 
2182 	err = got_fileindex_entry_add(fileindex, ie);
2183 	if (err) {
2184 		got_fileindex_entry_free(ie);
2185 		return err;
2186 	}
2187 
2188 	return report_file_status(ie, relpath, status_cb, status_arg, repo);
2189 }
2190 
2191 const struct got_error *
2192 got_worktree_schedule_add(struct got_worktree *worktree,
2193     struct got_pathlist_head *ondisk_paths,
2194     got_worktree_status_cb status_cb, void *status_arg,
2195     struct got_repository *repo)
2196 {
2197 	struct got_fileindex *fileindex = NULL;
2198 	char *fileindex_path = NULL;
2199 	FILE *index = NULL;
2200 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2201 	struct got_pathlist_entry *pe;
2202 
2203 	err = lock_worktree(worktree, LOCK_EX);
2204 	if (err)
2205 		return err;
2206 
2207 
2208 	fileindex = got_fileindex_alloc();
2209 	if (fileindex == NULL) {
2210 		err = got_error_from_errno("got_fileindex_alloc");
2211 		goto done;
2212 	}
2213 
2214 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2215 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2216 		err = got_error_from_errno("asprintf");
2217 		fileindex_path = NULL;
2218 		goto done;
2219 	}
2220 
2221 	index = fopen(fileindex_path, "rb");
2222 	if (index == NULL) {
2223 		err = got_error_from_errno2("fopen", fileindex_path);
2224 		goto done;
2225 	}
2226 
2227 	err = got_fileindex_read(fileindex, index);
2228 	if (err)
2229 		goto done;
2230 
2231 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2232 		char *relpath;
2233 		err = got_path_skip_common_ancestor(&relpath,
2234 		    got_worktree_get_root_path(worktree), pe->path);
2235 		if (err)
2236 			break;
2237 		err = schedule_addition(pe->path, fileindex, relpath,
2238 		    status_cb, status_arg, repo);
2239 		free(relpath);
2240 		if (err)
2241 			break;
2242 	}
2243 	sync_err = sync_fileindex(fileindex, fileindex_path);
2244 	if (sync_err && err == NULL)
2245 		err = sync_err;
2246 done:
2247 	if (index) {
2248 		if (fclose(index) != 0 && err == NULL)
2249 			err = got_error_from_errno("fclose");
2250 	}
2251 	if (fileindex)
2252 		got_fileindex_free(fileindex);
2253 	unlockerr = lock_worktree(worktree, LOCK_SH);
2254 	if (unlockerr && err == NULL)
2255 		err = unlockerr;
2256 	return err;
2257 }
2258 
2259 static const struct got_error *
2260 schedule_for_deletion(const char *ondisk_path, struct got_fileindex *fileindex,
2261     const char *relpath, int delete_local_mods,
2262     got_worktree_status_cb status_cb, void *status_arg,
2263     struct got_repository *repo)
2264 {
2265 	const struct got_error *err = NULL;
2266 	struct got_fileindex_entry *ie = NULL;
2267 	unsigned char status;
2268 	struct stat sb;
2269 
2270 	ie = got_fileindex_entry_get(fileindex, relpath);
2271 	if (ie == NULL)
2272 		return got_error(GOT_ERR_BAD_PATH);
2273 
2274 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2275 	if (err)
2276 		return err;
2277 
2278 	if (status != GOT_STATUS_NO_CHANGE) {
2279 		if (status == GOT_STATUS_DELETE)
2280 			return got_error_set_errno(ENOENT, ondisk_path);
2281 		if (status != GOT_STATUS_MODIFY)
2282 			return got_error(GOT_ERR_FILE_STATUS);
2283 		if (!delete_local_mods)
2284 			return got_error(GOT_ERR_FILE_MODIFIED);
2285 	}
2286 
2287 	if (unlink(ondisk_path) != 0)
2288 		return got_error_from_errno2("unlink", ondisk_path);
2289 
2290 	got_fileindex_entry_mark_deleted_from_disk(ie);
2291 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2292 }
2293 
2294 const struct got_error *
2295 got_worktree_schedule_delete(struct got_worktree *worktree,
2296     struct got_pathlist_head *ondisk_paths, int delete_local_mods,
2297     got_worktree_status_cb status_cb, void *status_arg,
2298     struct got_repository *repo)
2299 {
2300 	struct got_fileindex *fileindex = NULL;
2301 	char *fileindex_path = NULL;
2302 	FILE *index = NULL;
2303 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2304 	struct got_pathlist_entry *pe;
2305 
2306 	err = lock_worktree(worktree, LOCK_EX);
2307 	if (err)
2308 		return err;
2309 
2310 	fileindex = got_fileindex_alloc();
2311 	if (fileindex == NULL) {
2312 		err = got_error_from_errno("got_fileindex_alloc");
2313 		goto done;
2314 	}
2315 
2316 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2317 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2318 		err = got_error_from_errno("asprintf");
2319 		fileindex_path = NULL;
2320 		goto done;
2321 	}
2322 
2323 	index = fopen(fileindex_path, "rb");
2324 	if (index == NULL) {
2325 		err = got_error_from_errno2("fopen", fileindex_path);
2326 		goto done;
2327 	}
2328 
2329 	err = got_fileindex_read(fileindex, index);
2330 	if (err)
2331 		goto done;
2332 
2333 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2334 		char *relpath;
2335 		err = got_path_skip_common_ancestor(&relpath,
2336 		    got_worktree_get_root_path(worktree), pe->path);
2337 		if (err)
2338 			break;
2339 		err = schedule_for_deletion(pe->path, fileindex, relpath,
2340 		    delete_local_mods, status_cb, status_arg, repo);
2341 		free(relpath);
2342 		if (err)
2343 			break;
2344 	}
2345 	sync_err = sync_fileindex(fileindex, fileindex_path);
2346 	if (sync_err && err == NULL)
2347 		err = sync_err;
2348 done:
2349 	if (index) {
2350 		if (fclose(index) != 0 && err == NULL)
2351 			err = got_error_from_errno("fclose");
2352 	}
2353 	if (fileindex)
2354 		got_fileindex_free(fileindex);
2355 	unlockerr = lock_worktree(worktree, LOCK_SH);
2356 	if (unlockerr && err == NULL)
2357 		err = unlockerr;
2358 	return err;
2359 }
2360 
2361 static const struct got_error *
2362 revert_file(struct got_worktree *worktree, struct got_fileindex *fileindex,
2363     const char *ondisk_path,
2364     got_worktree_checkout_cb progress_cb, void *progress_arg,
2365     struct got_repository *repo)
2366 {
2367 	const struct got_error *err = NULL;
2368 	char *relpath = NULL, *parent_path = NULL;
2369 	struct got_fileindex_entry *ie;
2370 	struct got_tree_object *tree = NULL;
2371 	struct got_object_id *tree_id = NULL;
2372 	const struct got_tree_entry *te;
2373 	char *tree_path = NULL, *te_name;
2374 	struct got_blob_object *blob = NULL;
2375 	unsigned char status;
2376 	struct stat sb;
2377 
2378 	err = got_path_skip_common_ancestor(&relpath,
2379 	    got_worktree_get_root_path(worktree), ondisk_path);
2380 	if (err)
2381 		goto done;
2382 
2383 	ie = got_fileindex_entry_get(fileindex, relpath);
2384 	if (ie == NULL) {
2385 		err = got_error(GOT_ERR_BAD_PATH);
2386 		goto done;
2387 	}
2388 
2389 	/* Construct in-repository path of tree which contains this blob. */
2390 	err = got_path_dirname(&parent_path, ie->path);
2391 	if (err) {
2392 		if (err->code != GOT_ERR_BAD_PATH)
2393 			goto done;
2394 		parent_path = strdup("/");
2395 		if (parent_path == NULL) {
2396 			err = got_error_from_errno("strdup");
2397 			goto done;
2398 		}
2399 	}
2400 	if (got_path_is_root_dir(worktree->path_prefix)) {
2401 		tree_path = strdup(parent_path);
2402 		if (tree_path == NULL) {
2403 			err = got_error_from_errno("strdup");
2404 			goto done;
2405 		}
2406 	} else {
2407 		if (got_path_is_root_dir(parent_path)) {
2408 			tree_path = strdup(worktree->path_prefix);
2409 			if (tree_path == NULL) {
2410 				err = got_error_from_errno("strdup");
2411 				goto done;
2412 			}
2413 		} else {
2414 			if (asprintf(&tree_path, "%s/%s",
2415 			    worktree->path_prefix, parent_path) == -1) {
2416 				err = got_error_from_errno("asprintf");
2417 				goto done;
2418 			}
2419 		}
2420 	}
2421 
2422 	err = got_object_id_by_path(&tree_id, repo, worktree->base_commit_id,
2423 	    tree_path);
2424 	if (err)
2425 		goto done;
2426 
2427 	err = got_object_open_as_tree(&tree, repo, tree_id);
2428 	if (err)
2429 		goto done;
2430 
2431 	te_name = basename(ie->path);
2432 	if (te_name == NULL) {
2433 		err = got_error_from_errno2("basename", ie->path);
2434 		goto done;
2435 	}
2436 
2437 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2438 	if (err)
2439 		goto done;
2440 
2441 	te = got_object_tree_find_entry(tree, te_name);
2442 	if (te == NULL && status != GOT_STATUS_ADD) {
2443 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
2444 		goto done;
2445 	}
2446 
2447 	switch (status) {
2448 	case GOT_STATUS_ADD:
2449 		(*progress_cb)(progress_arg, GOT_STATUS_REVERT, ie->path);
2450 		got_fileindex_entry_remove(fileindex, ie);
2451 		break;
2452 	case GOT_STATUS_DELETE:
2453 	case GOT_STATUS_MODIFY:
2454 	case GOT_STATUS_CONFLICT:
2455 	case GOT_STATUS_MISSING: {
2456 		struct got_object_id id;
2457 		memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2458 		err = got_object_open_as_blob(&blob, repo, &id, 8192);
2459 		if (err)
2460 			goto done;
2461 		err = install_blob(worktree, ondisk_path, ie->path,
2462 		    te->mode, sb.st_mode, blob, 0, 1, repo, progress_cb,
2463 		    progress_arg);
2464 		if (err)
2465 			goto done;
2466 		if (status == GOT_STATUS_DELETE) {
2467 			err = update_blob_fileindex_entry(worktree,
2468 			    fileindex, ie, ondisk_path, ie->path, blob, 1);
2469 			if (err)
2470 				goto done;
2471 		}
2472 		break;
2473 	}
2474 	default:
2475 			goto done;
2476 	}
2477 done:
2478 	free(relpath);
2479 	free(parent_path);
2480 	free(tree_path);
2481 	if (blob)
2482 		got_object_blob_close(blob);
2483 	if (tree)
2484 		got_object_tree_close(tree);
2485 	free(tree_id);
2486 	return err;
2487 }
2488 
2489 const struct got_error *
2490 got_worktree_revert(struct got_worktree *worktree,
2491     struct got_pathlist_head *ondisk_paths,
2492     got_worktree_checkout_cb progress_cb, void *progress_arg,
2493     struct got_repository *repo)
2494 {
2495 	struct got_fileindex *fileindex = NULL;
2496 	char *fileindex_path = NULL;
2497 	FILE *index = NULL;
2498 	const struct got_error *err = NULL, *unlockerr = NULL;
2499 	const struct got_error *sync_err = NULL;
2500 	struct got_pathlist_entry *pe;
2501 
2502 	err = lock_worktree(worktree, LOCK_EX);
2503 	if (err)
2504 		return err;
2505 
2506 	fileindex = got_fileindex_alloc();
2507 	if (fileindex == NULL) {
2508 		err = got_error_from_errno("got_fileindex_alloc");
2509 		goto done;
2510 	}
2511 
2512 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2513 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2514 		err = got_error_from_errno("asprintf");
2515 		fileindex_path = NULL;
2516 		goto done;
2517 	}
2518 
2519 	index = fopen(fileindex_path, "rb");
2520 	if (index == NULL) {
2521 		err = got_error_from_errno2("fopen", fileindex_path);
2522 		goto done;
2523 	}
2524 
2525 	err = got_fileindex_read(fileindex, index);
2526 	if (err)
2527 		goto done;
2528 
2529 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2530 		err = revert_file(worktree, fileindex, pe->path,
2531 		    progress_cb, progress_arg, repo);
2532 		if (err)
2533 			break;
2534 	}
2535 	sync_err = sync_fileindex(fileindex, fileindex_path);
2536 	if (sync_err && err == NULL)
2537 		err = sync_err;
2538 done:
2539 	if (index) {
2540 		if (fclose(index) != 0 && err == NULL)
2541 			err = got_error_from_errno("fclose");
2542 	}
2543 	if (fileindex)
2544 		got_fileindex_free(fileindex);
2545 	unlockerr = lock_worktree(worktree, LOCK_SH);
2546 	if (unlockerr && err == NULL)
2547 		err = unlockerr;
2548 	return err;
2549 }
2550 
2551 static void
2552 free_commitable(struct got_commitable *ct)
2553 {
2554 	free(ct->path);
2555 	free(ct->in_repo_path);
2556 	free(ct->ondisk_path);
2557 	free(ct->blob_id);
2558 	free(ct->base_blob_id);
2559 	free(ct->base_commit_id);
2560 	free(ct);
2561 }
2562 
2563 struct collect_commitables_arg {
2564 	struct got_pathlist_head *commitable_paths;
2565 	struct got_repository *repo;
2566 	struct got_worktree *worktree;
2567 };
2568 
2569 static const struct got_error *
2570 collect_commitables(void *arg, unsigned char status, const char *relpath,
2571     struct got_object_id *blob_id, struct got_object_id *commit_id)
2572 {
2573 	struct collect_commitables_arg *a = arg;
2574 	const struct got_error *err = NULL;
2575 	struct got_commitable *ct = NULL;
2576 	struct got_pathlist_entry *new = NULL;
2577 	char *parent_path = NULL, *path = NULL;
2578 	struct stat sb;
2579 
2580 	if (status == GOT_STATUS_CONFLICT)
2581 		return got_error(GOT_ERR_COMMIT_CONFLICT);
2582 
2583 	if (status != GOT_STATUS_MODIFY && status != GOT_STATUS_ADD &&
2584 	    status != GOT_STATUS_DELETE)
2585 		return NULL;
2586 
2587 	if (asprintf(&path, "/%s", relpath) == -1) {
2588 		err = got_error_from_errno("asprintf");
2589 		goto done;
2590 	}
2591 	if (strcmp(path, "/") == 0) {
2592 		parent_path = strdup("");
2593 		if (parent_path == NULL)
2594 			return got_error_from_errno("strdup");
2595 	} else {
2596 		err = got_path_dirname(&parent_path, path);
2597 		if (err)
2598 			return err;
2599 	}
2600 
2601 	ct = calloc(1, sizeof(*ct));
2602 	if (ct == NULL) {
2603 		err = got_error_from_errno("calloc");
2604 		goto done;
2605 	}
2606 
2607 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
2608 	    relpath) == -1) {
2609 		err = got_error_from_errno("asprintf");
2610 		goto done;
2611 	}
2612 	if (status == GOT_STATUS_DELETE) {
2613 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
2614 	} else {
2615 		if (lstat(ct->ondisk_path, &sb) != 0) {
2616 			err = got_error_from_errno2("lstat", ct->ondisk_path);
2617 			goto done;
2618 		}
2619 		ct->mode = sb.st_mode;
2620 	}
2621 
2622 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
2623 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
2624 	    relpath) == -1) {
2625 		err = got_error_from_errno("asprintf");
2626 		goto done;
2627 	}
2628 
2629 	ct->status = status;
2630 	ct->blob_id = NULL; /* will be filled in when blob gets created */
2631 	if (ct->status != GOT_STATUS_ADD) {
2632 		ct->base_blob_id = got_object_id_dup(blob_id);
2633 		if (ct->base_blob_id == NULL) {
2634 			err = got_error_from_errno("got_object_id_dup");
2635 			goto done;
2636 		}
2637 		ct->base_commit_id = got_object_id_dup(commit_id);
2638 		if (ct->base_commit_id == NULL) {
2639 			err = got_error_from_errno("got_object_id_dup");
2640 			goto done;
2641 		}
2642 	}
2643 	ct->path = strdup(path);
2644 	if (ct->path == NULL) {
2645 		err = got_error_from_errno("strdup");
2646 		goto done;
2647 	}
2648 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
2649 done:
2650 	if (ct && (err || new == NULL))
2651 		free_commitable(ct);
2652 	free(parent_path);
2653 	free(path);
2654 	return err;
2655 }
2656 
2657 static const struct got_error *write_tree(struct got_object_id **,
2658     struct got_tree_object *, const char *, struct got_pathlist_head *,
2659     got_worktree_status_cb status_cb, void *status_arg,
2660     struct got_repository *);
2661 
2662 static const struct got_error *
2663 write_subtree(struct got_object_id **new_subtree_id,
2664     struct got_tree_entry *te, const char *parent_path,
2665     struct got_pathlist_head *commitable_paths,
2666     got_worktree_status_cb status_cb, void *status_arg,
2667     struct got_repository *repo)
2668 {
2669 	const struct got_error *err = NULL;
2670 	struct got_tree_object *subtree;
2671 	char *subpath;
2672 
2673 	if (asprintf(&subpath, "%s%s%s", parent_path,
2674 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
2675 		return got_error_from_errno("asprintf");
2676 
2677 	err = got_object_open_as_tree(&subtree, repo, te->id);
2678 	if (err)
2679 		return err;
2680 
2681 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
2682 	    status_cb, status_arg, repo);
2683 	got_object_tree_close(subtree);
2684 	free(subpath);
2685 	return err;
2686 }
2687 
2688 static const struct got_error *
2689 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
2690 {
2691 	const struct got_error *err = NULL;
2692 	char *ct_parent_path = NULL;
2693 
2694 	*match = 0;
2695 
2696 	if (strchr(ct->path, '/') == NULL) {
2697 		*match = got_path_is_root_dir(path);
2698 		return NULL;
2699 	}
2700 
2701 	err = got_path_dirname(&ct_parent_path, ct->path);
2702 	if (err)
2703 		return err;
2704 	*match = (strcmp(path, ct_parent_path) == 0);
2705 	free(ct_parent_path);
2706 	return err;
2707 }
2708 
2709 static mode_t
2710 get_ct_file_mode(struct got_commitable *ct)
2711 {
2712 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
2713 }
2714 
2715 static const struct got_error *
2716 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
2717     struct got_tree_entry *te, struct got_commitable *ct)
2718 {
2719 	const struct got_error *err = NULL;
2720 
2721 	*new_te = NULL;
2722 
2723 	err = got_object_tree_entry_dup(new_te, te);
2724 	if (err)
2725 		goto done;
2726 
2727 	(*new_te)->mode = get_ct_file_mode(ct);
2728 
2729 	free((*new_te)->id);
2730 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2731 	if ((*new_te)->id == NULL) {
2732 		err = got_error_from_errno("got_object_id_dup");
2733 		goto done;
2734 	}
2735 done:
2736 	if (err && *new_te) {
2737 		got_object_tree_entry_close(*new_te);
2738 		*new_te = NULL;
2739 	}
2740 	return err;
2741 }
2742 
2743 static const struct got_error *
2744 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
2745     struct got_commitable *ct)
2746 {
2747 	const struct got_error *err = NULL;
2748 	char *ct_name;
2749 
2750 	 *new_te = NULL;
2751 
2752 	*new_te = calloc(1, sizeof(**new_te));
2753 	if (*new_te == NULL)
2754 		return got_error_from_errno("calloc");
2755 
2756 	ct_name = basename(ct->path);
2757 	if (ct_name == NULL) {
2758 		err = got_error_from_errno2("basename", ct->path);
2759 		goto done;
2760 	}
2761 	(*new_te)->name = strdup(ct_name);
2762 	if ((*new_te)->name == NULL) {
2763 		err = got_error_from_errno("strdup");
2764 		goto done;
2765 	}
2766 
2767 	(*new_te)->mode = get_ct_file_mode(ct);
2768 
2769 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2770 	if ((*new_te)->id == NULL) {
2771 		err = got_error_from_errno("got_object_id_dup");
2772 		goto done;
2773 	}
2774 done:
2775 	if (err && *new_te) {
2776 		got_object_tree_entry_close(*new_te);
2777 		*new_te = NULL;
2778 	}
2779 	return err;
2780 }
2781 
2782 static const struct got_error *
2783 insert_tree_entry(struct got_tree_entry *new_te,
2784     struct got_pathlist_head *paths)
2785 {
2786 	const struct got_error *err = NULL;
2787 	struct got_pathlist_entry *new_pe;
2788 
2789 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
2790 	if (err)
2791 		return err;
2792 	if (new_pe == NULL)
2793 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
2794 	return NULL;
2795 }
2796 
2797 static const struct got_error *
2798 report_ct_status(struct got_commitable *ct,
2799     got_worktree_status_cb status_cb, void *status_arg)
2800 {
2801 	const char *ct_path = ct->path;
2802 	while (ct_path[0] == '/')
2803 		ct_path++;
2804 	return (*status_cb)(status_arg, ct->status, ct_path, ct->blob_id, NULL);
2805 }
2806 
2807 static const struct got_error *
2808 match_modified_subtree(int *modified, struct got_tree_entry *te,
2809     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
2810 {
2811 	const struct got_error *err = NULL;
2812 	struct got_pathlist_entry *pe;
2813 	char *te_path;
2814 
2815 	*modified = 0;
2816 
2817 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
2818 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
2819 	    te->name) == -1)
2820 		return got_error_from_errno("asprintf");
2821 
2822 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2823 		struct got_commitable *ct = pe->data;
2824 		*modified = got_path_is_child(ct->in_repo_path, te_path,
2825 		    strlen(te_path));
2826 		 if (*modified)
2827 			break;
2828 	}
2829 
2830 	free(te_path);
2831 	return err;
2832 }
2833 
2834 static const struct got_error *
2835 match_deleted_or_modified_ct(struct got_commitable **ctp,
2836     struct got_tree_entry *te, const char *base_tree_path,
2837     struct got_pathlist_head *commitable_paths)
2838 {
2839 	const struct got_error *err = NULL;
2840 	struct got_pathlist_entry *pe;
2841 
2842 	*ctp = NULL;
2843 
2844 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2845 		struct got_commitable *ct = pe->data;
2846 		char *ct_name = NULL;
2847 		int path_matches;
2848 
2849 		if (ct->status != GOT_STATUS_MODIFY &&
2850 		    ct->status != GOT_STATUS_DELETE)
2851 			continue;
2852 
2853 		if (got_object_id_cmp(ct->base_blob_id, te->id) != 0)
2854 			continue;
2855 
2856 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
2857 		 if (err)
2858 			return err;
2859 		if (!path_matches)
2860 			continue;
2861 
2862 		ct_name = basename(pe->path);
2863 		if (ct_name == NULL)
2864 			return got_error_from_errno2("basename", pe->path);
2865 
2866 		if (strcmp(te->name, ct_name) != 0)
2867 			continue;
2868 
2869 		*ctp = ct;
2870 		break;
2871 	}
2872 
2873 	return err;
2874 }
2875 
2876 static const struct got_error *
2877 write_tree(struct got_object_id **new_tree_id,
2878     struct got_tree_object *base_tree, const char *path_base_tree,
2879     struct got_pathlist_head *commitable_paths,
2880     got_worktree_status_cb status_cb, void *status_arg,
2881     struct got_repository *repo)
2882 {
2883 	const struct got_error *err = NULL;
2884 	const struct got_tree_entries *base_entries = NULL;
2885 	struct got_pathlist_head paths;
2886 	struct got_tree_entries new_tree_entries;
2887 	struct got_tree_entry *te, *new_te = NULL;
2888 	struct got_pathlist_entry *pe;
2889 
2890 	TAILQ_INIT(&paths);
2891 	new_tree_entries.nentries = 0;
2892 	SIMPLEQ_INIT(&new_tree_entries.head);
2893 
2894 	/* Insert, and recurse into, newly added entries first. */
2895 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2896 		struct got_commitable *ct = pe->data;
2897 		char *child_path = NULL, *slash;
2898 
2899 		if (ct->status != GOT_STATUS_ADD ||
2900 		    (ct->flags & GOT_COMMITABLE_ADDED))
2901 			continue;
2902 
2903 		 if (!got_path_is_child(pe->path, path_base_tree,
2904 		     strlen(path_base_tree)))
2905 			continue;
2906 
2907 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
2908 		    pe->path);
2909 		if (err)
2910 			goto done;
2911 
2912 		slash = strchr(child_path, '/');
2913 		if (slash == NULL) {
2914 			err = alloc_added_blob_tree_entry(&new_te, ct);
2915 			if (err)
2916 				goto done;
2917 			err = report_ct_status(ct, status_cb, status_arg);
2918 			if (err)
2919 				goto done;
2920 			ct->flags |= GOT_COMMITABLE_ADDED;
2921 		} else {
2922 			char *subtree_path;
2923 
2924 			*slash = '\0'; /* trim trailing path components */
2925 			if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
2926 			    got_path_is_root_dir(path_base_tree) ? "" : "/",
2927 			    child_path) == -1) {
2928 				err = got_error_from_errno("asprintf");
2929 				goto done;
2930 			}
2931 
2932 			new_te = calloc(1, sizeof(*new_te));
2933 			new_te->mode = S_IFDIR;
2934 			new_te->name = strdup(child_path);
2935 			if (new_te->name == NULL) {
2936 				err = got_error_from_errno("strdup");
2937 				got_object_tree_entry_close(new_te);
2938 				new_te = NULL;
2939 				goto done;
2940 			}
2941 			err = write_tree(&new_te->id, NULL, subtree_path,
2942 			    commitable_paths, status_cb, status_arg, repo);
2943 			free(subtree_path);
2944 			if (err) {
2945 				got_object_tree_entry_close(new_te);
2946 				new_te = NULL;
2947 				goto done;
2948 			}
2949 		}
2950 		err = insert_tree_entry(new_te, &paths);
2951 		if (err)
2952 			goto done;
2953 	}
2954 
2955 	if (base_tree) {
2956 		/* Handle modified and deleted entries. */
2957 		base_entries = got_object_tree_get_entries(base_tree);
2958 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
2959 			struct got_commitable *ct = NULL;
2960 
2961 			if (S_ISDIR(te->mode)) {
2962 				int modified;
2963 				err = got_object_tree_entry_dup(&new_te, te);
2964 				if (err)
2965 					goto done;
2966 				err = match_modified_subtree(&modified, te,
2967 				    path_base_tree, commitable_paths);
2968 				if (err)
2969 					goto done;
2970 				/* Avoid recursion into unmodified subtrees. */
2971 				if (modified) {
2972 					free(new_te->id);
2973 					err = write_subtree(&new_te->id, te,
2974 					    path_base_tree, commitable_paths,
2975 					    status_cb, status_arg, repo);
2976 					if (err)
2977 						goto done;
2978 				}
2979 				err = insert_tree_entry(new_te, &paths);
2980 				if (err)
2981 					goto done;
2982 				continue;
2983 			}
2984 
2985 			err = match_deleted_or_modified_ct(&ct, te,
2986 			    path_base_tree, commitable_paths);
2987 			if (ct) {
2988 				/* NB: Deleted entries get dropped here. */
2989 				if (ct->status == GOT_STATUS_MODIFY) {
2990 					err = alloc_modified_blob_tree_entry(
2991 					    &new_te, te, ct);
2992 					if (err)
2993 						goto done;
2994 					err = insert_tree_entry(new_te, &paths);
2995 					if (err)
2996 						goto done;
2997 				}
2998 				err = report_ct_status(ct, status_cb,
2999 				    status_arg);
3000 				if (err)
3001 					goto done;
3002 			} else {
3003 				/* Entry is unchanged; just copy it. */
3004 				err = got_object_tree_entry_dup(&new_te, te);
3005 				if (err)
3006 					goto done;
3007 				err = insert_tree_entry(new_te, &paths);
3008 				if (err)
3009 					goto done;
3010 			}
3011 		}
3012 	}
3013 
3014 	/* Write new list of entries; deleted entries have been dropped. */
3015 	TAILQ_FOREACH(pe, &paths, entry) {
3016 		struct got_tree_entry *te = pe->data;
3017 		new_tree_entries.nentries++;
3018 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
3019 	}
3020 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
3021 done:
3022 	got_object_tree_entries_close(&new_tree_entries);
3023 	got_pathlist_free(&paths);
3024 	return err;
3025 }
3026 
3027 static const struct got_error *
3028 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
3029     struct got_object_id *new_base_commit_id, struct got_worktree *worktree)
3030 {
3031 	const struct got_error *err = NULL, *sync_err;
3032 	char *fileindex_path = NULL;
3033 	struct got_fileindex *fileindex = NULL;
3034 	struct got_pathlist_entry *pe;
3035 
3036 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3037 	if (err)
3038 		return err;
3039 
3040 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3041 		struct got_fileindex_entry *ie;
3042 		struct got_commitable *ct = pe->data;
3043 
3044 		ie = got_fileindex_entry_get(fileindex, pe->path);
3045 		if (ie) {
3046 			if (ct->status == GOT_STATUS_DELETE) {
3047 				got_fileindex_entry_remove(fileindex, ie);
3048 				got_fileindex_entry_free(ie);
3049 			} else
3050 				err = got_fileindex_entry_update(ie,
3051 				    ct->ondisk_path, ct->blob_id->sha1,
3052 				    new_base_commit_id->sha1, 1);
3053 		} else {
3054 			err = got_fileindex_entry_alloc(&ie,
3055 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
3056 			    new_base_commit_id->sha1);
3057 			if (err)
3058 				break;
3059 			err = got_fileindex_entry_add(fileindex, ie);
3060 			if (err)
3061 				break;
3062 		}
3063 	}
3064 	sync_err = sync_fileindex(fileindex, fileindex_path);
3065 	if (sync_err && err == NULL)
3066 		err = sync_err;
3067 	free(fileindex_path);
3068 	got_fileindex_free(fileindex);
3069 	return err;
3070 }
3071 
3072 static const struct got_error *
3073 check_ct_out_of_date(struct got_commitable *ct, struct got_repository *repo,
3074 	struct got_object_id *head_commit_id)
3075 {
3076 	const struct got_error *err = NULL;
3077 	struct got_object_id *id_in_head = NULL, *id = NULL;
3078 	struct got_commit_object *commit = NULL;
3079 	char *path = NULL;
3080 	const char *ct_path = ct->in_repo_path;
3081 
3082 	while (ct_path[0] == '/')
3083 		ct_path++;
3084 
3085 	/*
3086 	 * Ensure that no modifications were made to files *and their parents*
3087 	 * in commits between the file's base commit and the branch head.
3088 	 *
3089 	 * Checking the parents is important for detecting conflicting tree
3090 	 * configurations (files or parent folders might have been moved,
3091 	 * deleted, added again, etc.). Such changes need to be merged with
3092 	 * local changes before a commit can occur.
3093 	 *
3094 	 * The implication is that the file's (parent) entry in the root
3095 	 * directory must have the same ID in all relevant commits.
3096 	 */
3097 	if (ct->status != GOT_STATUS_ADD) {
3098 		struct got_object_qid *pid;
3099 		char *slash;
3100 		struct got_object_id *root_entry_id = NULL;
3101 
3102 		/* Trivial case: base commit == head commit */
3103 		if (got_object_id_cmp(ct->base_commit_id, head_commit_id) == 0)
3104 			return NULL;
3105 
3106 		/* Compute the path to the root directory's entry. */
3107 		path = strdup(ct_path);
3108 		if (path == NULL) {
3109 			err = got_error_from_errno("strdup");
3110 			goto done;
3111 		}
3112 		slash = strchr(path, '/');
3113 		if (slash)
3114 			*slash = '\0';
3115 
3116 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
3117 		if (err)
3118 			goto done;
3119 
3120 		err = got_object_id_by_path(&root_entry_id, repo,
3121 		    head_commit_id, path);
3122 		if (err)
3123 			goto done;
3124 
3125 		pid = SIMPLEQ_FIRST(got_object_commit_get_parent_ids(commit));
3126 		while (pid) {
3127 			struct got_commit_object *pcommit;
3128 
3129 			err = got_object_id_by_path(&id, repo, pid->id, path);
3130 			if (err) {
3131 				if (err->code != GOT_ERR_NO_TREE_ENTRY)
3132 					goto done;
3133 				err = NULL;
3134 				break;
3135 			}
3136 
3137 			err = got_object_id_by_path(&id, repo, pid->id, path);
3138 			if (err)
3139 				goto done;
3140 
3141 			if (got_object_id_cmp(id, root_entry_id) != 0) {
3142 				err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
3143 				break;
3144 			}
3145 
3146 			if (got_object_id_cmp(pid->id, ct->base_commit_id) == 0)
3147 				break; /* all relevant commits scanned */
3148 
3149 			err = got_object_open_as_commit(&pcommit, repo,
3150 			    pid->id);
3151 			if (err)
3152 				goto done;
3153 
3154 			got_object_commit_close(commit);
3155 			commit = pcommit;
3156 			pid = SIMPLEQ_FIRST(got_object_commit_get_parent_ids(
3157 			    commit));
3158 		}
3159 	} else {
3160 		/* Require that added files don't exist in the branch head. */
3161 		err = got_object_id_by_path(&id_in_head, repo, head_commit_id,
3162 		    ct_path);
3163 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3164 			goto done;
3165 		err = id_in_head ? got_error(GOT_ERR_COMMIT_OUT_OF_DATE) : NULL;
3166 	}
3167 done:
3168 	if (commit)
3169 		got_object_commit_close(commit);
3170 	free(id_in_head);
3171 	free(id);
3172 	free(path);
3173 	return err;
3174 }
3175 
3176 const struct got_error *
3177 got_worktree_commit(struct got_object_id **new_commit_id,
3178     struct got_worktree *worktree, const char *ondisk_path,
3179     const char *author, const char *committer,
3180     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3181     got_worktree_status_cb status_cb, void *status_arg,
3182     struct got_repository *repo)
3183 {
3184 	const struct got_error *err = NULL, *unlockerr = NULL;
3185 	struct collect_commitables_arg cc_arg;
3186 	struct got_pathlist_head commitable_paths;
3187 	struct got_pathlist_entry *pe;
3188 	char *relpath = NULL;
3189 	const char *head_ref_name = NULL;
3190 	struct got_reference *head_ref = NULL;
3191 	struct got_commit_object *head_commit = NULL;
3192 	struct got_object_id *head_commit_id = NULL;
3193 	struct got_reference *head_ref2 = NULL;
3194 	struct got_object_id *head_commit_id2 = NULL;
3195 	struct got_tree_object *head_tree = NULL;
3196 	struct got_object_id *new_tree_id = NULL;
3197 	struct got_object_id_queue parent_ids;
3198 	struct got_object_qid *pid = NULL;
3199 	char *logmsg = NULL;
3200 
3201 	*new_commit_id = NULL;
3202 
3203 	TAILQ_INIT(&commitable_paths);
3204 	SIMPLEQ_INIT(&parent_ids);
3205 
3206 	if (ondisk_path) {
3207 		err = got_path_skip_common_ancestor(&relpath,
3208 		    worktree->root_path, ondisk_path);
3209 		if (err)
3210 			return err;
3211 	}
3212 
3213 	err = lock_worktree(worktree, LOCK_EX);
3214 	if (err)
3215 		goto done;
3216 
3217 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
3218 	if (err)
3219 		goto done;
3220 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
3221 	if (err)
3222 		goto done;
3223 
3224 	cc_arg.commitable_paths = &commitable_paths;
3225 	cc_arg.worktree = worktree;
3226 	cc_arg.repo = repo;
3227 	err = got_worktree_status(worktree, relpath ? relpath : "",
3228 	    repo, collect_commitables, &cc_arg, NULL, NULL);
3229 	if (err)
3230 		goto done;
3231 
3232 	if (TAILQ_EMPTY(&commitable_paths)) {
3233 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
3234 		goto done;
3235 	}
3236 
3237 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
3238 	if (err)
3239 		goto done;
3240 
3241 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3242 		struct got_commitable *ct = pe->data;
3243 		err = check_ct_out_of_date(ct, repo, head_commit_id);
3244 		if (err)
3245 			goto done;
3246 	}
3247 
3248 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
3249 	if (err)
3250 		goto done;
3251 
3252 	if (commit_msg_cb != NULL) {
3253 		err = commit_msg_cb(&commitable_paths, &logmsg, commit_arg);
3254 		if (err)
3255 			goto done;
3256 	}
3257 
3258 	if (logmsg == NULL || strlen(logmsg) == 0) {
3259 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
3260 		goto done;
3261 	}
3262 
3263 	/* Create blobs from added and modified files and record their IDs. */
3264 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3265 		struct got_commitable *ct = pe->data;
3266 		char *ondisk_path;
3267 
3268 		if (ct->status != GOT_STATUS_ADD &&
3269 		    ct->status != GOT_STATUS_MODIFY)
3270 			continue;
3271 
3272 		if (asprintf(&ondisk_path, "%s/%s",
3273 		    worktree->root_path, pe->path) == -1) {
3274 			err = got_error_from_errno("asprintf");
3275 			goto done;
3276 		}
3277 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
3278 		free(ondisk_path);
3279 		if (err)
3280 			goto done;
3281 	}
3282 
3283 	/* Recursively write new tree objects. */
3284 	err = write_tree(&new_tree_id, head_tree, "/", &commitable_paths,
3285 	    status_cb, status_arg, repo);
3286 	if (err)
3287 		goto done;
3288 
3289 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
3290 	if (err)
3291 		goto done;
3292 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
3293 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
3294 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
3295 	got_object_qid_free(pid);
3296 	if (logmsg != NULL)
3297 		free(logmsg);
3298 	if (err)
3299 		goto done;
3300 
3301 	/* Check if a concurrent commit to our branch has occurred. */
3302 	head_ref_name = got_worktree_get_head_ref_name(worktree);
3303 	if (head_ref_name == NULL) {
3304 		err = got_error_from_errno("got_worktree_get_head_ref_name");
3305 		goto done;
3306 	}
3307 	/* Lock the reference here to prevent concurrent modification. */
3308 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
3309 	if (err)
3310 		goto done;
3311 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
3312 	if (err)
3313 		goto done;
3314 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
3315 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
3316 		goto done;
3317 	}
3318 	/* Update branch head in repository. */
3319 	err = got_ref_change_ref(head_ref2, *new_commit_id);
3320 	if (err)
3321 		goto done;
3322 	err = got_ref_write(head_ref2, repo);
3323 	if (err)
3324 		goto done;
3325 
3326 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
3327 	if (err)
3328 		goto done;
3329 
3330 	err = ref_base_commit(worktree, repo);
3331 	if (err)
3332 		goto done;
3333 
3334 	err = update_fileindex_after_commit(&commitable_paths,
3335 	    *new_commit_id, worktree);
3336 	if (err)
3337 		goto done;
3338 done:
3339 	unlockerr = lock_worktree(worktree, LOCK_SH);
3340 	if (unlockerr && err == NULL)
3341 		err = unlockerr;
3342 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3343 		struct got_commitable *ct = pe->data;
3344 		free_commitable(ct);
3345 	}
3346 	got_pathlist_free(&commitable_paths);
3347 	if (head_tree)
3348 		got_object_tree_close(head_tree);
3349 	if (head_commit)
3350 		got_object_commit_close(head_commit);
3351 	free(relpath);
3352 	free(head_commit_id);
3353 	free(head_commit_id2);
3354 	if (head_ref)
3355 		got_ref_close(head_ref);
3356 	if (head_ref2) {
3357 		unlockerr = got_ref_unlock(head_ref2);
3358 		if (unlockerr && err == NULL)
3359 			err = unlockerr;
3360 		got_ref_close(head_ref2);
3361 	}
3362 	return err;
3363 }
3364 
3365 const char *
3366 got_commitable_get_path(struct got_commitable *ct)
3367 {
3368 	return ct->path;
3369 }
3370 
3371 unsigned int
3372 got_commitable_get_status(struct got_commitable *ct)
3373 {
3374 	return ct->status;
3375 }