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_object_id *deriv_base_commit_id,
729     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
730     void *progress_arg)
731 {
732 	const struct got_error *err = NULL;
733 	int merged_fd = -1;
734 	FILE *f_deriv = NULL, *f_orig = NULL;
735 	char *blob_deriv_path = NULL, *blob_orig_path = NULL;
736 	char *merged_path = NULL, *base_path = NULL;
737 	char *id_str = NULL;
738 	char *label_deriv = NULL;
739 	int overlapcnt = 0;
740 	char *parent;
741 
742 	*local_changes_subsumed = 0;
743 
744 	parent = dirname(ondisk_path);
745 	if (parent == NULL)
746 		return got_error_from_errno2("dirname", ondisk_path);
747 
748 	if (asprintf(&base_path, "%s/got-merged", parent) == -1)
749 		return got_error_from_errno("asprintf");
750 
751 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
752 	if (err)
753 		goto done;
754 
755 	free(base_path);
756 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
757 		err = got_error_from_errno("asprintf");
758 		base_path = NULL;
759 		goto done;
760 	}
761 
762 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path);
763 	if (err)
764 		goto done;
765 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
766 	    blob_deriv);
767 	if (err)
768 		goto done;
769 
770 	free(base_path);
771 	if (asprintf(&base_path, "%s/got-merge-blob-orig", parent) == -1) {
772 		err = got_error_from_errno("asprintf");
773 		base_path = NULL;
774 		goto done;
775 	}
776 
777 	err = got_opentemp_named(&blob_orig_path, &f_orig, base_path);
778 	if (err)
779 		goto done;
780 	if (blob_orig) {
781 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
782 		    blob_orig);
783 		if (err)
784 			goto done;
785 	} else {
786 		/*
787 		 * If the file has no blob, this is an "add vs add" conflict,
788 		 * and we simply use an empty ancestor file to make both files
789 		 * appear in the merged result in their entirety.
790 		 */
791 	}
792 
793 	err = got_object_id_str(&id_str, deriv_base_commit_id);
794 	if (err)
795 		goto done;
796 	if (asprintf(&label_deriv, "commit %s", id_str) == -1) {
797 		err = got_error_from_errno("asprintf");
798 		goto done;
799 	}
800 
801 	err = got_merge_diff3(&overlapcnt, merged_fd, blob_deriv_path,
802 	    blob_orig_path, ondisk_path, label_deriv, path);
803 	if (err)
804 		goto done;
805 
806 	err = (*progress_cb)(progress_arg,
807 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
808 	if (err)
809 		goto done;
810 
811 	if (fsync(merged_fd) != 0) {
812 		err = got_error_from_errno("fsync");
813 		goto done;
814 	}
815 
816 	/* Check if a clean merge has subsumed all local changes. */
817 	if (overlapcnt == 0) {
818 		err = check_files_equal(local_changes_subsumed, blob_deriv_path,
819 		    merged_path);
820 		if (err)
821 			goto done;
822 	}
823 
824 	if (chmod(merged_path, st_mode) != 0) {
825 		err = got_error_from_errno2("chmod", merged_path);
826 		goto done;
827 	}
828 
829 	if (rename(merged_path, ondisk_path) != 0) {
830 		err = got_error_from_errno3("rename", merged_path,
831 		    ondisk_path);
832 		unlink(merged_path);
833 		goto done;
834 	}
835 
836 done:
837 	if (merged_fd != -1 && close(merged_fd) != 0 && err == NULL)
838 		err = got_error_from_errno("close");
839 	if (f_deriv && fclose(f_deriv) != 0 && err == NULL)
840 		err = got_error_from_errno("fclose");
841 	if (f_orig && fclose(f_orig) != 0 && err == NULL)
842 		err = got_error_from_errno("fclose");
843 	free(merged_path);
844 	free(base_path);
845 	if (blob_deriv_path) {
846 		unlink(blob_deriv_path);
847 		free(blob_deriv_path);
848 	}
849 	if (blob_orig_path) {
850 		unlink(blob_orig_path);
851 		free(blob_orig_path);
852 	}
853 	free(id_str);
854 	free(label_deriv);
855 	return err;
856 }
857 
858 static const struct got_error *
859 update_blob_fileindex_entry(struct got_worktree *worktree,
860     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
861     const char *ondisk_path, const char *path, struct got_blob_object *blob,
862     int update_timestamps)
863 {
864 	const struct got_error *err = NULL;
865 
866 	if (ie == NULL)
867 		ie = got_fileindex_entry_get(fileindex, path);
868 	if (ie)
869 		err = got_fileindex_entry_update(ie, ondisk_path,
870 		    blob->id.sha1, worktree->base_commit_id->sha1,
871 		    update_timestamps);
872 	else {
873 		struct got_fileindex_entry *new_ie;
874 		err = got_fileindex_entry_alloc(&new_ie, ondisk_path,
875 		    path, blob->id.sha1, worktree->base_commit_id->sha1);
876 		if (!err)
877 			err = got_fileindex_entry_add(fileindex, new_ie);
878 	}
879 	return err;
880 }
881 
882 static const struct got_error *
883 install_blob(struct got_worktree *worktree, const char *ondisk_path,
884    const char *path, uint16_t te_mode, uint16_t st_mode,
885    struct got_blob_object *blob, int restoring_missing_file,
886    int reverting_versioned_file, struct got_repository *repo,
887    got_worktree_checkout_cb progress_cb, void *progress_arg)
888 {
889 	const struct got_error *err = NULL;
890 	int fd = -1;
891 	size_t len, hdrlen;
892 	int update = 0;
893 	char *tmppath = NULL;
894 
895 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
896 	    GOT_DEFAULT_FILE_MODE);
897 	if (fd == -1) {
898 		if (errno == ENOENT) {
899 			char *parent = dirname(path);
900 			if (parent == NULL)
901 				return got_error_from_errno2("dirname", path);
902 			err = add_dir_on_disk(worktree, parent);
903 			if (err)
904 				return err;
905 			fd = open(ondisk_path,
906 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
907 			    GOT_DEFAULT_FILE_MODE);
908 			if (fd == -1)
909 				return got_error_from_errno2("open",
910 				    ondisk_path);
911 		} else if (errno == EEXIST) {
912 			if (!S_ISREG(st_mode)) {
913 				/* TODO file is obstructed; do something */
914 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
915 				goto done;
916 			} else {
917 				err = got_opentemp_named_fd(&tmppath, &fd,
918 				    ondisk_path);
919 				if (err)
920 					goto done;
921 				update = 1;
922 			}
923 		} else
924 			return got_error_from_errno2("open", ondisk_path);
925 	}
926 
927 	if (restoring_missing_file)
928 		err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING, path);
929 	else if (reverting_versioned_file)
930 		err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT, path);
931 	else
932 		err = (*progress_cb)(progress_arg,
933 		    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
934 	if (err)
935 		goto done;
936 
937 	hdrlen = got_object_blob_get_hdrlen(blob);
938 	do {
939 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
940 		err = got_object_blob_read_block(&len, blob);
941 		if (err)
942 			break;
943 		if (len > 0) {
944 			/* Skip blob object header first time around. */
945 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
946 			if (outlen == -1) {
947 				err = got_error_from_errno("write");
948 				goto done;
949 			} else if (outlen != len - hdrlen) {
950 				err = got_error(GOT_ERR_IO);
951 				goto done;
952 			}
953 			hdrlen = 0;
954 		}
955 	} while (len != 0);
956 
957 	if (fsync(fd) != 0) {
958 		err = got_error_from_errno("fsync");
959 		goto done;
960 	}
961 
962 	if (update) {
963 		if (rename(tmppath, ondisk_path) != 0) {
964 			err = got_error_from_errno3("rename", tmppath,
965 			    ondisk_path);
966 			unlink(tmppath);
967 			goto done;
968 		}
969 	}
970 
971 	if (te_mode & S_IXUSR) {
972 		if (chmod(ondisk_path, st_mode | S_IXUSR) == -1) {
973 			err = got_error_from_errno2("chmod", ondisk_path);
974 			goto done;
975 		}
976 	} else {
977 		if (chmod(ondisk_path, st_mode & ~S_IXUSR) == -1) {
978 			err = got_error_from_errno2("chmod", ondisk_path);
979 			goto done;
980 		}
981 	}
982 
983 done:
984 	if (fd != -1 && close(fd) != 0 && err == NULL)
985 		err = got_error_from_errno("close");
986 	free(tmppath);
987 	return err;
988 }
989 
990 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
991 static const struct got_error *
992 get_modified_file_content_status(unsigned char *status, FILE *f)
993 {
994 	const struct got_error *err = NULL;
995 	const char *markers[3] = {
996 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
997 		GOT_DIFF_CONFLICT_MARKER_SEP,
998 		GOT_DIFF_CONFLICT_MARKER_END
999 	};
1000 	int i = 0;
1001 	char *line;
1002 	size_t len;
1003 	const char delim[3] = {'\0', '\0', '\0'};
1004 
1005 	while (*status == GOT_STATUS_MODIFY) {
1006 		line = fparseln(f, &len, NULL, delim, 0);
1007 		if (line == NULL) {
1008 			if (feof(f))
1009 				break;
1010 			err = got_ferror(f, GOT_ERR_IO);
1011 			break;
1012 		}
1013 
1014 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1015 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1016 			    == 0)
1017 				*status = GOT_STATUS_CONFLICT;
1018 			else
1019 				i++;
1020 		}
1021 	}
1022 
1023 	return err;
1024 }
1025 
1026 static const struct got_error *
1027 get_file_status(unsigned char *status, struct stat *sb,
1028     struct got_fileindex_entry *ie, const char *abspath,
1029     struct got_repository *repo)
1030 {
1031 	const struct got_error *err = NULL;
1032 	struct got_object_id id;
1033 	size_t hdrlen;
1034 	FILE *f = NULL;
1035 	uint8_t fbuf[8192];
1036 	struct got_blob_object *blob = NULL;
1037 	size_t flen, blen;
1038 
1039 	*status = GOT_STATUS_NO_CHANGE;
1040 
1041 	if (lstat(abspath, sb) == -1) {
1042 		if (errno == ENOENT) {
1043 			if (ie) {
1044 				if (got_fileindex_entry_has_file_on_disk(ie))
1045 					*status = GOT_STATUS_MISSING;
1046 				else
1047 					*status = GOT_STATUS_DELETE;
1048 				sb->st_mode =
1049 				    ((ie->mode >> GOT_FILEIDX_MODE_PERMS_SHIFT)
1050 				    & (S_IRWXU | S_IRWXG | S_IRWXO));
1051 			} else
1052 				sb->st_mode = GOT_DEFAULT_FILE_MODE;
1053 			return NULL;
1054 		}
1055 		return got_error_from_errno2("lstat", abspath);
1056 	}
1057 
1058 	if (!S_ISREG(sb->st_mode)) {
1059 		*status = GOT_STATUS_OBSTRUCTED;
1060 		return NULL;
1061 	}
1062 
1063 	if (ie == NULL)
1064 		return NULL;
1065 
1066 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1067 		*status = GOT_STATUS_DELETE;
1068 		return NULL;
1069 	} else if (!got_fileindex_entry_has_blob(ie)) {
1070 		*status = GOT_STATUS_ADD;
1071 		return NULL;
1072 	}
1073 
1074 	if (ie->ctime_sec == sb->st_ctime &&
1075 	    ie->ctime_nsec == sb->st_ctimensec &&
1076 	    ie->mtime_sec == sb->st_mtime &&
1077 	    ie->mtime_sec == sb->st_mtime &&
1078 	    ie->mtime_nsec == sb->st_mtimensec &&
1079 	    ie->size == (sb->st_size & 0xffffffff))
1080 		return NULL;
1081 
1082 	memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1083 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1084 	if (err)
1085 		return err;
1086 
1087 	f = fopen(abspath, "r");
1088 	if (f == NULL) {
1089 		err = got_error_from_errno2("fopen", abspath);
1090 		goto done;
1091 	}
1092 	hdrlen = got_object_blob_get_hdrlen(blob);
1093 	for (;;) {
1094 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1095 		err = got_object_blob_read_block(&blen, blob);
1096 		if (err)
1097 			goto done;
1098 		/* Skip length of blob object header first time around. */
1099 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1100 		if (flen == 0 && ferror(f)) {
1101 			err = got_error_from_errno("fread");
1102 			goto done;
1103 		}
1104 		if (blen == 0) {
1105 			if (flen != 0)
1106 				*status = GOT_STATUS_MODIFY;
1107 			break;
1108 		} else if (flen == 0) {
1109 			if (blen != 0)
1110 				*status = GOT_STATUS_MODIFY;
1111 			break;
1112 		} else if (blen - hdrlen == flen) {
1113 			/* Skip blob object header first time around. */
1114 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1115 				*status = GOT_STATUS_MODIFY;
1116 				break;
1117 			}
1118 		} else {
1119 			*status = GOT_STATUS_MODIFY;
1120 			break;
1121 		}
1122 		hdrlen = 0;
1123 	}
1124 
1125 	if (*status == GOT_STATUS_MODIFY) {
1126 		rewind(f);
1127 		err = get_modified_file_content_status(status, f);
1128 	}
1129 done:
1130 	if (blob)
1131 		got_object_blob_close(blob);
1132 	if (f)
1133 		fclose(f);
1134 	return err;
1135 }
1136 
1137 static const struct got_error *
1138 update_blob(struct got_worktree *worktree,
1139     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1140     struct got_tree_entry *te, const char *path,
1141     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1142     void *progress_arg)
1143 {
1144 	const struct got_error *err = NULL;
1145 	struct got_blob_object *blob = NULL;
1146 	char *ondisk_path;
1147 	unsigned char status = GOT_STATUS_NO_CHANGE;
1148 	struct stat sb;
1149 
1150 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1151 		return got_error_from_errno("asprintf");
1152 
1153 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1154 	if (err)
1155 		goto done;
1156 
1157 	if (status == GOT_STATUS_OBSTRUCTED) {
1158 		err = (*progress_cb)(progress_arg, status, path);
1159 		goto done;
1160 	}
1161 
1162 	if (ie && status != GOT_STATUS_MISSING) {
1163 		if (got_fileindex_entry_has_commit(ie) &&
1164 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1165 		    SHA1_DIGEST_LENGTH) == 0) {
1166 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1167 			    path);
1168 			goto done;
1169 		}
1170 		if (got_fileindex_entry_has_blob(ie) &&
1171 		    memcmp(ie->blob_sha1, te->id->sha1,
1172 		    SHA1_DIGEST_LENGTH) == 0)
1173 			goto done;
1174 	}
1175 
1176 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1177 	if (err)
1178 		goto done;
1179 
1180 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1181 		int update_timestamps;
1182 		struct got_blob_object *blob2 = NULL;
1183 		if (got_fileindex_entry_has_blob(ie)) {
1184 			struct got_object_id id2;
1185 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1186 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
1187 			if (err)
1188 				goto done;
1189 		}
1190 		err = merge_blob(&update_timestamps, worktree, blob2,
1191 		    ondisk_path, path, sb.st_mode, blob,
1192 		    worktree->base_commit_id, repo,
1193 		    progress_cb, progress_arg);
1194 		if (blob2)
1195 			got_object_blob_close(blob2);
1196 		/*
1197 		 * Do not update timestamps of files with local changes.
1198 		 * Otherwise, a future status walk would treat them as
1199 		 * unmodified files again.
1200 		 */
1201 		err = got_fileindex_entry_update(ie, ondisk_path,
1202 		    blob->id.sha1, worktree->base_commit_id->sha1,
1203 		    update_timestamps);
1204 	} else if (status == GOT_STATUS_DELETE) {
1205 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1206 		if (err)
1207 			goto done;
1208 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1209 		    ondisk_path, path, blob, 0);
1210 		if (err)
1211 			goto done;
1212 	} else {
1213 		err = install_blob(worktree, ondisk_path, path, te->mode,
1214 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1215 		    repo, progress_cb, progress_arg);
1216 		if (err)
1217 			goto done;
1218 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1219 		    ondisk_path, path, blob, 1);
1220 		if (err)
1221 			goto done;
1222 	}
1223 	got_object_blob_close(blob);
1224 done:
1225 	free(ondisk_path);
1226 	return err;
1227 }
1228 
1229 static const struct got_error *
1230 remove_ondisk_file(const char *root_path, const char *path)
1231 {
1232 	const struct got_error *err = NULL;
1233 	char *ondisk_path = NULL;
1234 
1235 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1236 		return got_error_from_errno("asprintf");
1237 
1238 	if (unlink(ondisk_path) == -1) {
1239 		if (errno != ENOENT)
1240 			err = got_error_from_errno2("unlink", ondisk_path);
1241 	} else {
1242 		char *parent = dirname(ondisk_path);
1243 		while (parent && strcmp(parent, root_path) != 0) {
1244 			if (rmdir(parent) == -1) {
1245 				if (errno != ENOTEMPTY)
1246 					err = got_error_from_errno2("rmdir",
1247 					    parent);
1248 				break;
1249 			}
1250 			parent = dirname(parent);
1251 		}
1252 	}
1253 	free(ondisk_path);
1254 	return err;
1255 }
1256 
1257 static const struct got_error *
1258 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1259     struct got_fileindex_entry *ie, struct got_repository *repo,
1260     got_worktree_checkout_cb progress_cb, void *progress_arg)
1261 {
1262 	const struct got_error *err = NULL;
1263 	unsigned char status;
1264 	struct stat sb;
1265 	char *ondisk_path;
1266 
1267 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1268 	    == -1)
1269 		return got_error_from_errno("asprintf");
1270 
1271 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1272 	if (err)
1273 		return err;
1274 
1275 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1276 	    status == GOT_STATUS_ADD) {
1277 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1278 		if (err)
1279 			return err;
1280 		/*
1281 		 * Preserve the working file and change the deleted blob's
1282 		 * entry into a schedule-add entry.
1283 		 */
1284 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1285 		    0);
1286 		if (err)
1287 			return err;
1288 	} else {
1289 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1290 		if (err)
1291 			return err;
1292 		if (status == GOT_STATUS_NO_CHANGE) {
1293 			err = remove_ondisk_file(worktree->root_path, ie->path);
1294 			if (err)
1295 				return err;
1296 		}
1297 		got_fileindex_entry_remove(fileindex, ie);
1298 	}
1299 
1300 	return err;
1301 }
1302 
1303 struct diff_cb_arg {
1304     struct got_fileindex *fileindex;
1305     struct got_worktree *worktree;
1306     struct got_repository *repo;
1307     got_worktree_checkout_cb progress_cb;
1308     void *progress_arg;
1309     got_worktree_cancel_cb cancel_cb;
1310     void *cancel_arg;
1311 };
1312 
1313 static const struct got_error *
1314 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1315     struct got_tree_entry *te, const char *parent_path)
1316 {
1317 	struct diff_cb_arg *a = arg;
1318 
1319 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1320 		return got_error(GOT_ERR_CANCELLED);
1321 
1322 	return update_blob(a->worktree, a->fileindex, ie, te,
1323 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1324 }
1325 
1326 static const struct got_error *
1327 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1328 {
1329 	struct diff_cb_arg *a = arg;
1330 
1331 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1332 		return got_error(GOT_ERR_CANCELLED);
1333 
1334 	return delete_blob(a->worktree, a->fileindex, ie,
1335 	    a->repo, a->progress_cb, a->progress_arg);
1336 }
1337 
1338 static const struct got_error *
1339 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1340 {
1341 	struct diff_cb_arg *a = arg;
1342 	const struct got_error *err;
1343 	char *path;
1344 
1345 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1346 		return got_error(GOT_ERR_CANCELLED);
1347 
1348 	if (asprintf(&path, "%s%s%s", parent_path,
1349 	    parent_path[0] ? "/" : "", te->name)
1350 	    == -1)
1351 		return got_error_from_errno("asprintf");
1352 
1353 	if (S_ISDIR(te->mode))
1354 		err = add_dir_on_disk(a->worktree, path);
1355 	else
1356 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1357 		    a->repo, a->progress_cb, a->progress_arg);
1358 
1359 	free(path);
1360 	return err;
1361 }
1362 
1363 static const struct got_error *
1364 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
1365 {
1366 	const struct got_error *err = NULL;
1367 	char *uuidstr = NULL;
1368 	uint32_t uuid_status;
1369 
1370 	*refname = NULL;
1371 
1372 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1373 	if (uuid_status != uuid_s_ok)
1374 		return got_error_uuid(uuid_status);
1375 
1376 	if (asprintf(refname, "%s-%s", prefix, uuidstr)
1377 	    == -1) {
1378 		err = got_error_from_errno("asprintf");
1379 		*refname = NULL;
1380 	}
1381 	free(uuidstr);
1382 	return err;
1383 }
1384 
1385 const struct got_error *
1386 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1387 {
1388 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
1389 }
1390 
1391 static const struct got_error *
1392 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
1393 {
1394 	return get_ref_name(refname, worktree,
1395 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
1396 }
1397 
1398 static const struct got_error *
1399 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
1400 {
1401 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
1402 }
1403 
1404 static const struct got_error *
1405 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
1406 {
1407 	return get_ref_name(refname, worktree,
1408 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
1409 }
1410 
1411 static const struct got_error *
1412 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
1413 {
1414 	return get_ref_name(refname, worktree,
1415 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
1416 }
1417 
1418 
1419 /*
1420  * Prevent Git's garbage collector from deleting our base commit by
1421  * setting a reference to our base commit's ID.
1422  */
1423 static const struct got_error *
1424 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1425 {
1426 	const struct got_error *err = NULL;
1427 	struct got_reference *ref = NULL;
1428 	char *refname;
1429 
1430 	err = got_worktree_get_base_ref_name(&refname, worktree);
1431 	if (err)
1432 		return err;
1433 
1434 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1435 	if (err)
1436 		goto done;
1437 
1438 	err = got_ref_write(ref, repo);
1439 done:
1440 	free(refname);
1441 	if (ref)
1442 		got_ref_close(ref);
1443 	return err;
1444 }
1445 
1446 static const struct got_error *
1447 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1448    struct got_worktree *worktree)
1449 {
1450 	const struct got_error *err = NULL;
1451 	FILE *index = NULL;
1452 
1453 	*fileindex_path = NULL;
1454 	*fileindex = got_fileindex_alloc();
1455 	if (*fileindex == NULL)
1456 		return got_error_from_errno("got_fileindex_alloc");
1457 
1458 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1459 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1460 		err = got_error_from_errno("asprintf");
1461 		*fileindex_path = NULL;
1462 		goto done;
1463 	}
1464 
1465 	index = fopen(*fileindex_path, "rb");
1466 	if (index == NULL) {
1467 		if (errno != ENOENT)
1468 			err = got_error_from_errno2("fopen", *fileindex_path);
1469 	} else {
1470 		err = got_fileindex_read(*fileindex, index);
1471 		if (fclose(index) != 0 && err == NULL)
1472 			err = got_error_from_errno("fclose");
1473 	}
1474 done:
1475 	if (err) {
1476 		free(*fileindex_path);
1477 		*fileindex_path = NULL;
1478 		got_fileindex_free(*fileindex);
1479 		*fileindex = NULL;
1480 	}
1481 	return err;
1482 }
1483 
1484 struct bump_base_commit_id_arg {
1485 	struct got_object_id *base_commit_id;
1486 	const char *path;
1487 	size_t path_len;
1488 	const char *entry_name;
1489 	got_worktree_checkout_cb progress_cb;
1490 	void *progress_arg;
1491 };
1492 
1493 /* Bump base commit ID of all files within an updated part of the work tree. */
1494 static const struct got_error *
1495 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
1496 {
1497 	const struct got_error *err;
1498 	struct bump_base_commit_id_arg *a = arg;
1499 
1500 	if (a->entry_name) {
1501 		if (strcmp(ie->path, a->path) != 0)
1502 			return NULL;
1503 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
1504 		return NULL;
1505 
1506 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
1507 	    SHA1_DIGEST_LENGTH) == 0)
1508 		return NULL;
1509 
1510 	if (a->progress_cb) {
1511 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
1512 		    ie->path);
1513 		if (err)
1514 			return err;
1515 	}
1516 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
1517 	return NULL;
1518 }
1519 
1520 static const struct got_error *
1521 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
1522 {
1523 	const struct got_error *err = NULL;
1524 	char *new_fileindex_path = NULL;
1525 	FILE *new_index = NULL;
1526 
1527 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1528 	    fileindex_path);
1529 	if (err)
1530 		goto done;
1531 
1532 	err = got_fileindex_write(fileindex, new_index);
1533 	if (err)
1534 		goto done;
1535 
1536 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1537 		err = got_error_from_errno3("rename", new_fileindex_path,
1538 		    fileindex_path);
1539 		unlink(new_fileindex_path);
1540 	}
1541 done:
1542 	if (new_index)
1543 		fclose(new_index);
1544 	free(new_fileindex_path);
1545 	return err;
1546 }
1547 
1548 static const struct got_error *
1549 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
1550     struct got_object_id **tree_id, const char *wt_relpath,
1551     struct got_worktree *worktree, struct got_repository *repo)
1552 {
1553 	const struct got_error *err = NULL;
1554 	struct got_object_id *id = NULL;
1555 	char *in_repo_path = NULL;
1556 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
1557 
1558 	*entry_type = GOT_OBJ_TYPE_ANY;
1559 	*tree_relpath = NULL;
1560 	*tree_id = NULL;
1561 
1562 	if (wt_relpath[0] == '\0') {
1563 		/* Check out all files within the work tree. */
1564 		*entry_type = GOT_OBJ_TYPE_TREE;
1565 		*tree_relpath = strdup("");
1566 		if (*tree_relpath == NULL) {
1567 			err = got_error_from_errno("strdup");
1568 			goto done;
1569 		}
1570 		err = got_object_id_by_path(tree_id, repo,
1571 		    worktree->base_commit_id, worktree->path_prefix);
1572 		if (err)
1573 			goto done;
1574 		return NULL;
1575 	}
1576 
1577 	/* Check out a subset of files in the work tree. */
1578 
1579 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
1580 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
1581 		err = got_error_from_errno("asprintf");
1582 		goto done;
1583 	}
1584 
1585 	err = got_object_id_by_path(&id, repo, worktree->base_commit_id,
1586 	    in_repo_path);
1587 	if (err)
1588 		goto done;
1589 
1590 	free(in_repo_path);
1591 	in_repo_path = NULL;
1592 
1593 	err = got_object_get_type(entry_type, repo, id);
1594 	if (err)
1595 		goto done;
1596 
1597 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
1598 		/* Check out a single file. */
1599 		if (strchr(wt_relpath, '/')  == NULL) {
1600 			/* Check out a single file in work tree's root dir. */
1601 			in_repo_path = strdup(worktree->path_prefix);
1602 			if (in_repo_path == NULL) {
1603 				err = got_error_from_errno("strdup");
1604 				goto done;
1605 			}
1606 			*tree_relpath = strdup("");
1607 			if (*tree_relpath == NULL) {
1608 				err = got_error_from_errno("strdup");
1609 				goto done;
1610 			}
1611 		} else {
1612 			/* Check out a single file in a subdirectory. */
1613 			err = got_path_dirname(tree_relpath, wt_relpath);
1614 			if (err)
1615 				return err;
1616 			if (asprintf(&in_repo_path, "%s%s%s",
1617 			    worktree->path_prefix, is_root_wt ? "" : "/",
1618 			    *tree_relpath) == -1) {
1619 				err = got_error_from_errno("asprintf");
1620 				goto done;
1621 			}
1622 		}
1623 		err = got_object_id_by_path(tree_id, repo,
1624 		    worktree->base_commit_id, in_repo_path);
1625 	} else {
1626 		/* Check out all files within a subdirectory. */
1627 		*tree_id = got_object_id_dup(id);
1628 		if (*tree_id == NULL) {
1629 			err = got_error_from_errno("got_object_id_dup");
1630 			goto done;
1631 		}
1632 		*tree_relpath = strdup(wt_relpath);
1633 		if (*tree_relpath == NULL) {
1634 			err = got_error_from_errno("strdup");
1635 			goto done;
1636 		}
1637 	}
1638 done:
1639 	free(id);
1640 	free(in_repo_path);
1641 	if (err) {
1642 		*entry_type = GOT_OBJ_TYPE_ANY;
1643 		free(*tree_relpath);
1644 		*tree_relpath = NULL;
1645 		free(*tree_id);
1646 		*tree_id = NULL;
1647 	}
1648 	return err;
1649 }
1650 
1651 static const struct got_error *
1652 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
1653     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
1654     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1655     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1656 {
1657 	const struct got_error *err = NULL;
1658 	struct got_commit_object *commit = NULL;
1659 	struct got_tree_object *tree = NULL;
1660 	struct got_fileindex_diff_tree_cb diff_cb;
1661 	struct diff_cb_arg arg;
1662 
1663 	err = ref_base_commit(worktree, repo);
1664 	if (err)
1665 		goto done;
1666 
1667 	err = got_object_open_as_commit(&commit, repo,
1668 	   worktree->base_commit_id);
1669 	if (err)
1670 		goto done;
1671 
1672 	err = got_object_open_as_tree(&tree, repo, tree_id);
1673 	if (err)
1674 		goto done;
1675 
1676 	if (entry_name &&
1677 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1678 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1679 		goto done;
1680 	}
1681 
1682 	diff_cb.diff_old_new = diff_old_new;
1683 	diff_cb.diff_old = diff_old;
1684 	diff_cb.diff_new = diff_new;
1685 	arg.fileindex = fileindex;
1686 	arg.worktree = worktree;
1687 	arg.repo = repo;
1688 	arg.progress_cb = progress_cb;
1689 	arg.progress_arg = progress_arg;
1690 	arg.cancel_cb = cancel_cb;
1691 	arg.cancel_arg = cancel_arg;
1692 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
1693 	    entry_name, repo, &diff_cb, &arg);
1694 done:
1695 	if (tree)
1696 		got_object_tree_close(tree);
1697 	if (commit)
1698 		got_object_commit_close(commit);
1699 	return err;
1700 }
1701 
1702 const struct got_error *
1703 got_worktree_checkout_files(struct got_worktree *worktree, const char *path,
1704     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1705     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1706 {
1707 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1708 	struct got_commit_object *commit = NULL;
1709 	struct got_object_id *tree_id = NULL;
1710 	struct got_tree_object *tree = NULL;
1711 	struct got_fileindex *fileindex = NULL;
1712 	char *fileindex_path = NULL;
1713 	char *relpath = NULL, *entry_name = NULL;
1714 	int entry_type;
1715 
1716 	err = lock_worktree(worktree, LOCK_EX);
1717 	if (err)
1718 		return err;
1719 
1720 	err = find_tree_entry_for_checkout(&entry_type, &relpath, &tree_id,
1721 	    path, worktree, repo);
1722 	if (err)
1723 		goto done;
1724 
1725 	if (entry_type == GOT_OBJ_TYPE_BLOB) {
1726 		entry_name = basename(path);
1727 		if (entry_name == NULL) {
1728 			err = got_error_from_errno2("basename", path);
1729 			goto done;
1730 		}
1731 	}
1732 
1733 	/*
1734 	 * Read the file index.
1735 	 * Checking out files is supposed to be an idempotent operation.
1736 	 * If the on-disk file index is incomplete we will try to complete it.
1737 	 */
1738 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1739 	if (err)
1740 		goto done;
1741 
1742 	err = checkout_files(worktree, fileindex, relpath, tree_id, entry_name,
1743 	    repo, progress_cb, progress_arg, cancel_cb, cancel_arg);
1744 	if (err == NULL) {
1745 		struct bump_base_commit_id_arg bbc_arg;
1746 		bbc_arg.base_commit_id = worktree->base_commit_id;
1747 		bbc_arg.entry_name = entry_name;
1748 		bbc_arg.path = path;
1749 		bbc_arg.path_len = strlen(path);
1750 		bbc_arg.progress_cb = progress_cb;
1751 		bbc_arg.progress_arg = progress_arg;
1752 		err = got_fileindex_for_each_entry_safe(fileindex,
1753 		    bump_base_commit_id, &bbc_arg);
1754 	}
1755 	sync_err = sync_fileindex(fileindex, fileindex_path);
1756 	if (sync_err && err == NULL)
1757 		err = sync_err;
1758 done:
1759 	free(fileindex_path);
1760 	free(relpath);
1761 	if (tree)
1762 		got_object_tree_close(tree);
1763 	if (commit)
1764 		got_object_commit_close(commit);
1765 	if (fileindex)
1766 		got_fileindex_free(fileindex);
1767 	unlockerr = lock_worktree(worktree, LOCK_SH);
1768 	if (unlockerr && err == NULL)
1769 		err = unlockerr;
1770 	return err;
1771 }
1772 
1773 struct merge_file_cb_arg {
1774     struct got_worktree *worktree;
1775     struct got_fileindex *fileindex;
1776     got_worktree_checkout_cb progress_cb;
1777     void *progress_arg;
1778     got_worktree_cancel_cb cancel_cb;
1779     void *cancel_arg;
1780     struct got_object_id *commit_id2;
1781 };
1782 
1783 static const struct got_error *
1784 merge_file_cb(void *arg, struct got_blob_object *blob1,
1785     struct got_blob_object *blob2, struct got_object_id *id1,
1786     struct got_object_id *id2, const char *path1, const char *path2,
1787     struct got_repository *repo)
1788 {
1789 	static const struct got_error *err = NULL;
1790 	struct merge_file_cb_arg *a = arg;
1791 	struct got_fileindex_entry *ie;
1792 	char *ondisk_path = NULL;
1793 	struct stat sb;
1794 	unsigned char status;
1795 	int local_changes_subsumed;
1796 
1797 	if (blob1 && blob2) {
1798 		ie = got_fileindex_entry_get(a->fileindex, path2);
1799 		if (ie == NULL)
1800 			return (*a->progress_cb)(a->progress_arg,
1801 			    GOT_STATUS_MISSING, path2);
1802 
1803 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1804 		    path2) == -1)
1805 			return got_error_from_errno("asprintf");
1806 
1807 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1808 		if (err)
1809 			goto done;
1810 
1811 		if (status == GOT_STATUS_DELETE) {
1812 			err = (*a->progress_cb)(a->progress_arg,
1813 			    GOT_STATUS_MERGE, path2);
1814 			goto done;
1815 		}
1816 		if (status != GOT_STATUS_NO_CHANGE &&
1817 		    status != GOT_STATUS_MODIFY &&
1818 		    status != GOT_STATUS_CONFLICT &&
1819 		    status != GOT_STATUS_ADD) {
1820 			err = (*a->progress_cb)(a->progress_arg, status, path2);
1821 			goto done;
1822 		}
1823 
1824 		err = merge_blob(&local_changes_subsumed, a->worktree, blob1,
1825 		    ondisk_path, path2, sb.st_mode, blob2, a->commit_id2, repo,
1826 		    a->progress_cb, a->progress_arg);
1827 	} else if (blob1) {
1828 		ie = got_fileindex_entry_get(a->fileindex, path1);
1829 		if (ie == NULL)
1830 			return (*a->progress_cb)(a->progress_arg,
1831 			    GOT_STATUS_MISSING, path2);
1832 
1833 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1834 		    path1) == -1)
1835 			return got_error_from_errno("asprintf");
1836 
1837 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1838 		if (err)
1839 			goto done;
1840 
1841 		switch (status) {
1842 		case GOT_STATUS_NO_CHANGE:
1843 			err = (*a->progress_cb)(a->progress_arg,
1844 			    GOT_STATUS_DELETE, path1);
1845 			if (err)
1846 				goto done;
1847 			err = remove_ondisk_file(a->worktree->root_path, path1);
1848 			if (err)
1849 				goto done;
1850 			if (ie)
1851 				got_fileindex_entry_mark_deleted_from_disk(ie);
1852 			break;
1853 		case GOT_STATUS_DELETE:
1854 		case GOT_STATUS_MISSING:
1855 			err = (*a->progress_cb)(a->progress_arg,
1856 			    GOT_STATUS_DELETE, path1);
1857 			if (err)
1858 				goto done;
1859 			if (ie)
1860 				got_fileindex_entry_mark_deleted_from_disk(ie);
1861 			break;
1862 		case GOT_STATUS_ADD:
1863 		case GOT_STATUS_MODIFY:
1864 		case GOT_STATUS_CONFLICT:
1865 			err = (*a->progress_cb)(a->progress_arg,
1866 			    GOT_STATUS_CANNOT_DELETE, path1);
1867 			if (err)
1868 				goto done;
1869 			break;
1870 		case GOT_STATUS_OBSTRUCTED:
1871 			err = (*a->progress_cb)(a->progress_arg, status, path1);
1872 			if (err)
1873 				goto done;
1874 			break;
1875 		default:
1876 			break;
1877 		}
1878 	} else if (blob2) {
1879 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1880 		    path2) == -1)
1881 			return got_error_from_errno("asprintf");
1882 		ie = got_fileindex_entry_get(a->fileindex, path2);
1883 		if (ie) {
1884 			err = get_file_status(&status, &sb, ie, ondisk_path,
1885 			    repo);
1886 			if (err)
1887 				goto done;
1888 			if (status != GOT_STATUS_NO_CHANGE &&
1889 			    status != GOT_STATUS_MODIFY &&
1890 			    status != GOT_STATUS_CONFLICT &&
1891 			    status != GOT_STATUS_ADD) {
1892 				err = (*a->progress_cb)(a->progress_arg,
1893 				    status, path2);
1894 				goto done;
1895 			}
1896 			err = merge_blob(&local_changes_subsumed, a->worktree,
1897 			    NULL, ondisk_path, path2, sb.st_mode, blob2,
1898 			    a->commit_id2, repo,
1899 			    a->progress_cb, a->progress_arg);
1900 			if (status == GOT_STATUS_DELETE) {
1901 				err = update_blob_fileindex_entry(a->worktree,
1902 				    a->fileindex, ie, ondisk_path, ie->path,
1903 				    blob2, 0);
1904 				if (err)
1905 					goto done;
1906 			}
1907 		} else {
1908 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
1909 			err = install_blob(a->worktree, ondisk_path, path2,
1910 			    /* XXX get this from parent tree! */
1911 			    GOT_DEFAULT_FILE_MODE,
1912 			    sb.st_mode, blob2, 0, 0, repo,
1913 			    a->progress_cb, a->progress_arg);
1914 			if (err)
1915 				goto done;
1916 			err = got_fileindex_entry_alloc(&ie,
1917 			    ondisk_path, path2, NULL, NULL);
1918 			if (err)
1919 				goto done;
1920 			err = got_fileindex_entry_add(a->fileindex, ie);
1921 			if (err) {
1922 				got_fileindex_entry_free(ie);
1923 				goto done;
1924 			}
1925 		}
1926 	}
1927 done:
1928 	free(ondisk_path);
1929 	return err;
1930 }
1931 
1932 struct check_merge_ok_arg {
1933 	struct got_worktree *worktree;
1934 	struct got_repository *repo;
1935 };
1936 
1937 static const struct got_error *
1938 check_merge_ok(void *arg, struct got_fileindex_entry *ie)
1939 {
1940 	const struct got_error *err = NULL;
1941 	struct check_merge_ok_arg *a = arg;
1942 	unsigned char status;
1943 	struct stat sb;
1944 	char *ondisk_path;
1945 
1946 	/* Reject merges into a work tree with mixed base commits. */
1947 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
1948 	    SHA1_DIGEST_LENGTH))
1949 		return got_error(GOT_ERR_MIXED_COMMITS);
1950 
1951 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
1952 	    == -1)
1953 		return got_error_from_errno("asprintf");
1954 
1955 	/* Reject merges into a work tree with conflicted files. */
1956 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
1957 	if (err)
1958 		return err;
1959 	if (status == GOT_STATUS_CONFLICT)
1960 		return got_error(GOT_ERR_CONFLICTS);
1961 
1962 	return NULL;
1963 }
1964 
1965 static const struct got_error *
1966 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
1967     const char *fileindex_path, struct got_object_id *commit_id1,
1968     struct got_object_id *commit_id2, struct got_repository *repo,
1969     got_worktree_checkout_cb progress_cb, void *progress_arg,
1970     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1971 {
1972 	const struct got_error *err = NULL, *sync_err;
1973 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
1974 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
1975 	struct merge_file_cb_arg arg;
1976 
1977 	if (commit_id1) {
1978 		err = got_object_id_by_path(&tree_id1, repo, commit_id1,
1979 		    worktree->path_prefix);
1980 		if (err)
1981 			goto done;
1982 
1983 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
1984 		if (err)
1985 			goto done;
1986 	}
1987 
1988 	err = got_object_id_by_path(&tree_id2, repo, commit_id2,
1989 	    worktree->path_prefix);
1990 	if (err)
1991 		goto done;
1992 
1993 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
1994 	if (err)
1995 		goto done;
1996 
1997 	arg.worktree = worktree;
1998 	arg.fileindex = fileindex;
1999 	arg.progress_cb = progress_cb;
2000 	arg.progress_arg = progress_arg;
2001 	arg.cancel_cb = cancel_cb;
2002 	arg.cancel_arg = cancel_arg;
2003 	arg.commit_id2 = commit_id2;
2004 	err = got_diff_tree(tree1, tree2, "", "", repo, merge_file_cb, &arg);
2005 	sync_err = sync_fileindex(fileindex, fileindex_path);
2006 	if (sync_err && err == NULL)
2007 		err = sync_err;
2008 done:
2009 	if (tree1)
2010 		got_object_tree_close(tree1);
2011 	if (tree2)
2012 		got_object_tree_close(tree2);
2013 	return err;
2014 }
2015 
2016 const struct got_error *
2017 got_worktree_merge_files(struct got_worktree *worktree,
2018     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
2019     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2020     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2021 {
2022 	const struct got_error *err, *unlockerr;
2023 	char *fileindex_path = NULL;
2024 	struct got_fileindex *fileindex = NULL;
2025 	struct check_merge_ok_arg mok_arg;
2026 
2027 	err = lock_worktree(worktree, LOCK_EX);
2028 	if (err)
2029 		return err;
2030 
2031 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2032 	if (err)
2033 		goto done;
2034 
2035 	mok_arg.worktree = worktree;
2036 	mok_arg.repo = repo;
2037 	err = got_fileindex_for_each_entry_safe(fileindex, check_merge_ok,
2038 	    &mok_arg);
2039 	if (err)
2040 		goto done;
2041 
2042 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
2043 	    commit_id2, repo, progress_cb, progress_arg, cancel_cb, cancel_arg);
2044 done:
2045 	if (fileindex)
2046 		got_fileindex_free(fileindex);
2047 	free(fileindex_path);
2048 	unlockerr = lock_worktree(worktree, LOCK_SH);
2049 	if (unlockerr && err == NULL)
2050 		err = unlockerr;
2051 	return err;
2052 }
2053 
2054 struct diff_dir_cb_arg {
2055     struct got_fileindex *fileindex;
2056     struct got_worktree *worktree;
2057     const char *status_path;
2058     size_t status_path_len;
2059     struct got_repository *repo;
2060     got_worktree_status_cb status_cb;
2061     void *status_arg;
2062     got_worktree_cancel_cb cancel_cb;
2063     void *cancel_arg;
2064 };
2065 
2066 static const struct got_error *
2067 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
2068     got_worktree_status_cb status_cb, void *status_arg,
2069     struct got_repository *repo)
2070 {
2071 	const struct got_error *err = NULL;
2072 	unsigned char status = GOT_STATUS_NO_CHANGE;
2073 	struct stat sb;
2074 	struct got_object_id blob_id, commit_id;
2075 
2076 	err = get_file_status(&status, &sb, ie, abspath, repo);
2077 	if (err == NULL && status != GOT_STATUS_NO_CHANGE) {
2078 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2079 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2080 		err = (*status_cb)(status_arg, status, ie->path, &blob_id,
2081 		    &commit_id);
2082 	}
2083 	return err;
2084 }
2085 
2086 static const struct got_error *
2087 status_old_new(void *arg, struct got_fileindex_entry *ie,
2088     struct dirent *de, const char *parent_path)
2089 {
2090 	const struct got_error *err = NULL;
2091 	struct diff_dir_cb_arg *a = arg;
2092 	char *abspath;
2093 
2094 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2095 		return got_error(GOT_ERR_CANCELLED);
2096 
2097 	if (got_path_cmp(parent_path, a->status_path) != 0 &&
2098 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
2099 		return NULL;
2100 
2101 	if (parent_path[0]) {
2102 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
2103 		    parent_path, de->d_name) == -1)
2104 			return got_error_from_errno("asprintf");
2105 	} else {
2106 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
2107 		    de->d_name) == -1)
2108 			return got_error_from_errno("asprintf");
2109 	}
2110 
2111 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
2112 	    a->repo);
2113 	free(abspath);
2114 	return err;
2115 }
2116 
2117 static const struct got_error *
2118 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2119 {
2120 	struct diff_dir_cb_arg *a = arg;
2121 	struct got_object_id blob_id, commit_id;
2122 	unsigned char status;
2123 
2124 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2125 		return got_error(GOT_ERR_CANCELLED);
2126 
2127 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
2128 		return NULL;
2129 
2130 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2131 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2132 	if (got_fileindex_entry_has_file_on_disk(ie))
2133 		status = GOT_STATUS_MISSING;
2134 	else
2135 		status = GOT_STATUS_DELETE;
2136 	return (*a->status_cb)(a->status_arg, status, ie->path, &blob_id,
2137 	    &commit_id);
2138 }
2139 
2140 static const struct got_error *
2141 status_new(void *arg, struct dirent *de, const char *parent_path)
2142 {
2143 	const struct got_error *err = NULL;
2144 	struct diff_dir_cb_arg *a = arg;
2145 	char *path = NULL;
2146 
2147 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2148 		return got_error(GOT_ERR_CANCELLED);
2149 
2150 	if (de->d_type == DT_DIR)
2151 		return NULL;
2152 
2153 	/* XXX ignore symlinks for now */
2154 	if (de->d_type == DT_LNK)
2155 		return NULL;
2156 
2157 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
2158 		return NULL;
2159 
2160 	if (parent_path[0]) {
2161 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
2162 			return got_error_from_errno("asprintf");
2163 	} else {
2164 		path = de->d_name;
2165 	}
2166 
2167 	err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED, path,
2168 	    NULL, NULL);
2169 	if (parent_path[0])
2170 		free(path);
2171 	return err;
2172 }
2173 
2174 static const struct got_error *
2175 worktree_status(struct got_worktree *worktree, const char *path,
2176     struct got_fileindex *fileindex, struct got_repository *repo,
2177     got_worktree_status_cb status_cb, void *status_arg,
2178     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2179 {
2180 	const struct got_error *err = NULL;
2181 	DIR *workdir = NULL;
2182 	struct got_fileindex_diff_dir_cb fdiff_cb;
2183 	struct diff_dir_cb_arg arg;
2184 	char *ondisk_path = NULL;
2185 
2186 	if (asprintf(&ondisk_path, "%s%s%s",
2187 	    worktree->root_path, path[0] ? "/" : "", path) == -1) {
2188 		err = got_error_from_errno("asprintf");
2189 		goto done;
2190 	}
2191 	workdir = opendir(ondisk_path);
2192 	if (workdir == NULL) {
2193 		if (errno == ENOTDIR || errno == ENOENT) {
2194 			struct got_fileindex_entry *ie;
2195 			ie = got_fileindex_entry_get(fileindex, path);
2196 			if (ie == NULL) {
2197 				err = got_error(GOT_ERR_BAD_PATH);
2198 				goto done;
2199 			}
2200 			err = report_file_status(ie, ondisk_path,
2201 			    status_cb, status_arg, repo);
2202 			goto done;
2203 		} else {
2204 			err = got_error_from_errno2("opendir", ondisk_path);
2205 			goto done;
2206 		}
2207 	}
2208 	fdiff_cb.diff_old_new = status_old_new;
2209 	fdiff_cb.diff_old = status_old;
2210 	fdiff_cb.diff_new = status_new;
2211 	arg.fileindex = fileindex;
2212 	arg.worktree = worktree;
2213 	arg.status_path = path;
2214 	arg.status_path_len = strlen(path);
2215 	arg.repo = repo;
2216 	arg.status_cb = status_cb;
2217 	arg.status_arg = status_arg;
2218 	arg.cancel_cb = cancel_cb;
2219 	arg.cancel_arg = cancel_arg;
2220 	err = got_fileindex_diff_dir(fileindex, workdir, worktree->root_path,
2221 	    path, repo, &fdiff_cb, &arg);
2222 done:
2223 	if (workdir)
2224 		closedir(workdir);
2225 	free(ondisk_path);
2226 	return err;
2227 }
2228 
2229 const struct got_error *
2230 got_worktree_status(struct got_worktree *worktree, const char *path,
2231     struct got_repository *repo, got_worktree_status_cb status_cb,
2232     void *status_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2233 {
2234 	const struct got_error *err = NULL;
2235 	char *fileindex_path = NULL;
2236 	struct got_fileindex *fileindex = NULL;
2237 
2238 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2239 	if (err)
2240 		return err;
2241 
2242 	err = worktree_status(worktree, path, fileindex, repo,
2243 	    status_cb, status_arg, cancel_cb, cancel_arg);
2244 	free(fileindex_path);
2245 	got_fileindex_free(fileindex);
2246 	return err;
2247 }
2248 
2249 const struct got_error *
2250 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
2251     const char *arg)
2252 {
2253 	const struct got_error *err = NULL;
2254 	char *resolved, *path = NULL;
2255 	size_t len;
2256 
2257 	*wt_path = NULL;
2258 
2259 	resolved = realpath(arg, NULL);
2260 	if (resolved == NULL)
2261 		return got_error_from_errno2("realpath", arg);
2262 
2263 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
2264 	    strlen(got_worktree_get_root_path(worktree)))) {
2265 		err = got_error(GOT_ERR_BAD_PATH);
2266 		goto done;
2267 	}
2268 
2269 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
2270 		err = got_path_skip_common_ancestor(&path,
2271 		    got_worktree_get_root_path(worktree), resolved);
2272 		if (err)
2273 			goto done;
2274 	} else {
2275 		path = strdup("");
2276 		if (path == NULL) {
2277 			err = got_error_from_errno("strdup");
2278 			goto done;
2279 		}
2280 	}
2281 
2282 	/* XXX status walk can't deal with trailing slash! */
2283 	len = strlen(path);
2284 	while (path[len - 1] == '/') {
2285 		path[len - 1] = '\0';
2286 		len--;
2287 	}
2288 done:
2289 	free(resolved);
2290 	if (err == NULL)
2291 		*wt_path = path;
2292 	else
2293 		free(path);
2294 	return err;
2295 }
2296 
2297 static const struct got_error *
2298 schedule_addition(const char *ondisk_path, struct got_fileindex *fileindex,
2299     const char *relpath, got_worktree_status_cb status_cb, void *status_arg,
2300     struct got_repository *repo)
2301 {
2302 	const struct got_error *err = NULL;
2303 	struct got_fileindex_entry *ie;
2304 
2305 	/* Re-adding an existing entry is a no-op. */
2306 	if (got_fileindex_entry_get(fileindex, relpath) != NULL)
2307 		return NULL;
2308 
2309 	err = got_fileindex_entry_alloc(&ie, ondisk_path, relpath, NULL, NULL);
2310 	if (err)
2311 		return err;
2312 
2313 	err = got_fileindex_entry_add(fileindex, ie);
2314 	if (err) {
2315 		got_fileindex_entry_free(ie);
2316 		return err;
2317 	}
2318 
2319 	return report_file_status(ie, relpath, status_cb, status_arg, repo);
2320 }
2321 
2322 const struct got_error *
2323 got_worktree_schedule_add(struct got_worktree *worktree,
2324     struct got_pathlist_head *ondisk_paths,
2325     got_worktree_status_cb status_cb, void *status_arg,
2326     struct got_repository *repo)
2327 {
2328 	struct got_fileindex *fileindex = NULL;
2329 	char *fileindex_path = NULL;
2330 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2331 	struct got_pathlist_entry *pe;
2332 
2333 	err = lock_worktree(worktree, LOCK_EX);
2334 	if (err)
2335 		return err;
2336 
2337 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2338 	if (err)
2339 		goto done;
2340 
2341 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2342 		char *relpath;
2343 		err = got_path_skip_common_ancestor(&relpath,
2344 		    got_worktree_get_root_path(worktree), pe->path);
2345 		if (err)
2346 			break;
2347 		err = schedule_addition(pe->path, fileindex, relpath,
2348 		    status_cb, status_arg, repo);
2349 		free(relpath);
2350 		if (err)
2351 			break;
2352 	}
2353 	sync_err = sync_fileindex(fileindex, fileindex_path);
2354 	if (sync_err && err == NULL)
2355 		err = sync_err;
2356 done:
2357 	free(fileindex_path);
2358 	if (fileindex)
2359 		got_fileindex_free(fileindex);
2360 	unlockerr = lock_worktree(worktree, LOCK_SH);
2361 	if (unlockerr && err == NULL)
2362 		err = unlockerr;
2363 	return err;
2364 }
2365 
2366 static const struct got_error *
2367 schedule_for_deletion(const char *ondisk_path, struct got_fileindex *fileindex,
2368     const char *relpath, int delete_local_mods,
2369     got_worktree_status_cb status_cb, void *status_arg,
2370     struct got_repository *repo)
2371 {
2372 	const struct got_error *err = NULL;
2373 	struct got_fileindex_entry *ie = NULL;
2374 	unsigned char status;
2375 	struct stat sb;
2376 
2377 	ie = got_fileindex_entry_get(fileindex, relpath);
2378 	if (ie == NULL)
2379 		return got_error(GOT_ERR_BAD_PATH);
2380 
2381 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2382 	if (err)
2383 		return err;
2384 
2385 	if (status != GOT_STATUS_NO_CHANGE) {
2386 		if (status == GOT_STATUS_DELETE)
2387 			return got_error_set_errno(ENOENT, ondisk_path);
2388 		if (status != GOT_STATUS_MODIFY)
2389 			return got_error(GOT_ERR_FILE_STATUS);
2390 		if (!delete_local_mods)
2391 			return got_error(GOT_ERR_FILE_MODIFIED);
2392 	}
2393 
2394 	if (unlink(ondisk_path) != 0)
2395 		return got_error_from_errno2("unlink", ondisk_path);
2396 
2397 	got_fileindex_entry_mark_deleted_from_disk(ie);
2398 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2399 }
2400 
2401 const struct got_error *
2402 got_worktree_schedule_delete(struct got_worktree *worktree,
2403     struct got_pathlist_head *ondisk_paths, int delete_local_mods,
2404     got_worktree_status_cb status_cb, void *status_arg,
2405     struct got_repository *repo)
2406 {
2407 	struct got_fileindex *fileindex = NULL;
2408 	char *fileindex_path = NULL;
2409 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2410 	struct got_pathlist_entry *pe;
2411 
2412 	err = lock_worktree(worktree, LOCK_EX);
2413 	if (err)
2414 		return err;
2415 
2416 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2417 	if (err)
2418 		goto done;
2419 
2420 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2421 		char *relpath;
2422 		err = got_path_skip_common_ancestor(&relpath,
2423 		    got_worktree_get_root_path(worktree), pe->path);
2424 		if (err)
2425 			break;
2426 		err = schedule_for_deletion(pe->path, fileindex, relpath,
2427 		    delete_local_mods, status_cb, status_arg, repo);
2428 		free(relpath);
2429 		if (err)
2430 			break;
2431 	}
2432 	sync_err = sync_fileindex(fileindex, fileindex_path);
2433 	if (sync_err && err == NULL)
2434 		err = sync_err;
2435 done:
2436 	free(fileindex_path);
2437 	if (fileindex)
2438 		got_fileindex_free(fileindex);
2439 	unlockerr = lock_worktree(worktree, LOCK_SH);
2440 	if (unlockerr && err == NULL)
2441 		err = unlockerr;
2442 	return err;
2443 }
2444 
2445 static const struct got_error *
2446 revert_file(struct got_worktree *worktree, struct got_fileindex *fileindex,
2447     const char *ondisk_path,
2448     got_worktree_checkout_cb progress_cb, void *progress_arg,
2449     struct got_repository *repo)
2450 {
2451 	const struct got_error *err = NULL;
2452 	char *relpath = NULL, *parent_path = NULL;
2453 	struct got_fileindex_entry *ie;
2454 	struct got_tree_object *tree = NULL;
2455 	struct got_object_id *tree_id = NULL;
2456 	const struct got_tree_entry *te;
2457 	char *tree_path = NULL, *te_name;
2458 	struct got_blob_object *blob = NULL;
2459 	unsigned char status;
2460 	struct stat sb;
2461 
2462 	err = got_path_skip_common_ancestor(&relpath,
2463 	    got_worktree_get_root_path(worktree), ondisk_path);
2464 	if (err)
2465 		goto done;
2466 
2467 	ie = got_fileindex_entry_get(fileindex, relpath);
2468 	if (ie == NULL) {
2469 		err = got_error(GOT_ERR_BAD_PATH);
2470 		goto done;
2471 	}
2472 
2473 	/* Construct in-repository path of tree which contains this blob. */
2474 	err = got_path_dirname(&parent_path, ie->path);
2475 	if (err) {
2476 		if (err->code != GOT_ERR_BAD_PATH)
2477 			goto done;
2478 		parent_path = strdup("/");
2479 		if (parent_path == NULL) {
2480 			err = got_error_from_errno("strdup");
2481 			goto done;
2482 		}
2483 	}
2484 	if (got_path_is_root_dir(worktree->path_prefix)) {
2485 		tree_path = strdup(parent_path);
2486 		if (tree_path == NULL) {
2487 			err = got_error_from_errno("strdup");
2488 			goto done;
2489 		}
2490 	} else {
2491 		if (got_path_is_root_dir(parent_path)) {
2492 			tree_path = strdup(worktree->path_prefix);
2493 			if (tree_path == NULL) {
2494 				err = got_error_from_errno("strdup");
2495 				goto done;
2496 			}
2497 		} else {
2498 			if (asprintf(&tree_path, "%s/%s",
2499 			    worktree->path_prefix, parent_path) == -1) {
2500 				err = got_error_from_errno("asprintf");
2501 				goto done;
2502 			}
2503 		}
2504 	}
2505 
2506 	err = got_object_id_by_path(&tree_id, repo, worktree->base_commit_id,
2507 	    tree_path);
2508 	if (err)
2509 		goto done;
2510 
2511 	err = got_object_open_as_tree(&tree, repo, tree_id);
2512 	if (err)
2513 		goto done;
2514 
2515 	te_name = basename(ie->path);
2516 	if (te_name == NULL) {
2517 		err = got_error_from_errno2("basename", ie->path);
2518 		goto done;
2519 	}
2520 
2521 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2522 	if (err)
2523 		goto done;
2524 
2525 	te = got_object_tree_find_entry(tree, te_name);
2526 	if (te == NULL && status != GOT_STATUS_ADD) {
2527 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
2528 		goto done;
2529 	}
2530 
2531 	switch (status) {
2532 	case GOT_STATUS_ADD:
2533 		err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT, ie->path);
2534 		if (err)
2535 			goto done;
2536 		got_fileindex_entry_remove(fileindex, ie);
2537 		break;
2538 	case GOT_STATUS_DELETE:
2539 	case GOT_STATUS_MODIFY:
2540 	case GOT_STATUS_CONFLICT:
2541 	case GOT_STATUS_MISSING: {
2542 		struct got_object_id id;
2543 		memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2544 		err = got_object_open_as_blob(&blob, repo, &id, 8192);
2545 		if (err)
2546 			goto done;
2547 		err = install_blob(worktree, ondisk_path, ie->path,
2548 		    te->mode, sb.st_mode, blob, 0, 1, repo, progress_cb,
2549 		    progress_arg);
2550 		if (err)
2551 			goto done;
2552 		if (status == GOT_STATUS_DELETE) {
2553 			err = update_blob_fileindex_entry(worktree,
2554 			    fileindex, ie, ondisk_path, ie->path, blob, 1);
2555 			if (err)
2556 				goto done;
2557 		}
2558 		break;
2559 	}
2560 	default:
2561 			goto done;
2562 	}
2563 done:
2564 	free(relpath);
2565 	free(parent_path);
2566 	free(tree_path);
2567 	if (blob)
2568 		got_object_blob_close(blob);
2569 	if (tree)
2570 		got_object_tree_close(tree);
2571 	free(tree_id);
2572 	return err;
2573 }
2574 
2575 const struct got_error *
2576 got_worktree_revert(struct got_worktree *worktree,
2577     struct got_pathlist_head *ondisk_paths,
2578     got_worktree_checkout_cb progress_cb, void *progress_arg,
2579     struct got_repository *repo)
2580 {
2581 	struct got_fileindex *fileindex = NULL;
2582 	char *fileindex_path = NULL;
2583 	const struct got_error *err = NULL, *unlockerr = NULL;
2584 	const struct got_error *sync_err = NULL;
2585 	struct got_pathlist_entry *pe;
2586 
2587 	err = lock_worktree(worktree, LOCK_EX);
2588 	if (err)
2589 		return err;
2590 
2591 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2592 	if (err)
2593 		goto done;
2594 
2595 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2596 		err = revert_file(worktree, fileindex, pe->path,
2597 		    progress_cb, progress_arg, repo);
2598 		if (err)
2599 			break;
2600 	}
2601 	sync_err = sync_fileindex(fileindex, fileindex_path);
2602 	if (sync_err && err == NULL)
2603 		err = sync_err;
2604 done:
2605 	free(fileindex_path);
2606 	if (fileindex)
2607 		got_fileindex_free(fileindex);
2608 	unlockerr = lock_worktree(worktree, LOCK_SH);
2609 	if (unlockerr && err == NULL)
2610 		err = unlockerr;
2611 	return err;
2612 }
2613 
2614 static void
2615 free_commitable(struct got_commitable *ct)
2616 {
2617 	free(ct->path);
2618 	free(ct->in_repo_path);
2619 	free(ct->ondisk_path);
2620 	free(ct->blob_id);
2621 	free(ct->base_blob_id);
2622 	free(ct->base_commit_id);
2623 	free(ct);
2624 }
2625 
2626 struct collect_commitables_arg {
2627 	struct got_pathlist_head *commitable_paths;
2628 	struct got_repository *repo;
2629 	struct got_worktree *worktree;
2630 };
2631 
2632 static const struct got_error *
2633 collect_commitables(void *arg, unsigned char status, const char *relpath,
2634     struct got_object_id *blob_id, struct got_object_id *commit_id)
2635 {
2636 	struct collect_commitables_arg *a = arg;
2637 	const struct got_error *err = NULL;
2638 	struct got_commitable *ct = NULL;
2639 	struct got_pathlist_entry *new = NULL;
2640 	char *parent_path = NULL, *path = NULL;
2641 	struct stat sb;
2642 
2643 	if (status == GOT_STATUS_CONFLICT)
2644 		return got_error(GOT_ERR_COMMIT_CONFLICT);
2645 
2646 	if (status != GOT_STATUS_MODIFY && status != GOT_STATUS_ADD &&
2647 	    status != GOT_STATUS_DELETE)
2648 		return NULL;
2649 
2650 	if (asprintf(&path, "/%s", relpath) == -1) {
2651 		err = got_error_from_errno("asprintf");
2652 		goto done;
2653 	}
2654 	if (strcmp(path, "/") == 0) {
2655 		parent_path = strdup("");
2656 		if (parent_path == NULL)
2657 			return got_error_from_errno("strdup");
2658 	} else {
2659 		err = got_path_dirname(&parent_path, path);
2660 		if (err)
2661 			return err;
2662 	}
2663 
2664 	ct = calloc(1, sizeof(*ct));
2665 	if (ct == NULL) {
2666 		err = got_error_from_errno("calloc");
2667 		goto done;
2668 	}
2669 
2670 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
2671 	    relpath) == -1) {
2672 		err = got_error_from_errno("asprintf");
2673 		goto done;
2674 	}
2675 	if (status == GOT_STATUS_DELETE) {
2676 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
2677 	} else {
2678 		if (lstat(ct->ondisk_path, &sb) != 0) {
2679 			err = got_error_from_errno2("lstat", ct->ondisk_path);
2680 			goto done;
2681 		}
2682 		ct->mode = sb.st_mode;
2683 	}
2684 
2685 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
2686 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
2687 	    relpath) == -1) {
2688 		err = got_error_from_errno("asprintf");
2689 		goto done;
2690 	}
2691 
2692 	ct->status = status;
2693 	ct->blob_id = NULL; /* will be filled in when blob gets created */
2694 	if (ct->status != GOT_STATUS_ADD) {
2695 		ct->base_blob_id = got_object_id_dup(blob_id);
2696 		if (ct->base_blob_id == NULL) {
2697 			err = got_error_from_errno("got_object_id_dup");
2698 			goto done;
2699 		}
2700 		ct->base_commit_id = got_object_id_dup(commit_id);
2701 		if (ct->base_commit_id == NULL) {
2702 			err = got_error_from_errno("got_object_id_dup");
2703 			goto done;
2704 		}
2705 	}
2706 	ct->path = strdup(path);
2707 	if (ct->path == NULL) {
2708 		err = got_error_from_errno("strdup");
2709 		goto done;
2710 	}
2711 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
2712 done:
2713 	if (ct && (err || new == NULL))
2714 		free_commitable(ct);
2715 	free(parent_path);
2716 	free(path);
2717 	return err;
2718 }
2719 
2720 static const struct got_error *write_tree(struct got_object_id **,
2721     struct got_tree_object *, const char *, struct got_pathlist_head *,
2722     got_worktree_status_cb status_cb, void *status_arg,
2723     struct got_repository *);
2724 
2725 static const struct got_error *
2726 write_subtree(struct got_object_id **new_subtree_id,
2727     struct got_tree_entry *te, const char *parent_path,
2728     struct got_pathlist_head *commitable_paths,
2729     got_worktree_status_cb status_cb, void *status_arg,
2730     struct got_repository *repo)
2731 {
2732 	const struct got_error *err = NULL;
2733 	struct got_tree_object *subtree;
2734 	char *subpath;
2735 
2736 	if (asprintf(&subpath, "%s%s%s", parent_path,
2737 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
2738 		return got_error_from_errno("asprintf");
2739 
2740 	err = got_object_open_as_tree(&subtree, repo, te->id);
2741 	if (err)
2742 		return err;
2743 
2744 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
2745 	    status_cb, status_arg, repo);
2746 	got_object_tree_close(subtree);
2747 	free(subpath);
2748 	return err;
2749 }
2750 
2751 static const struct got_error *
2752 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
2753 {
2754 	const struct got_error *err = NULL;
2755 	char *ct_parent_path = NULL;
2756 
2757 	*match = 0;
2758 
2759 	if (strchr(ct->path, '/') == NULL) {
2760 		*match = got_path_is_root_dir(path);
2761 		return NULL;
2762 	}
2763 
2764 	err = got_path_dirname(&ct_parent_path, ct->path);
2765 	if (err)
2766 		return err;
2767 	*match = (strcmp(path, ct_parent_path) == 0);
2768 	free(ct_parent_path);
2769 	return err;
2770 }
2771 
2772 static mode_t
2773 get_ct_file_mode(struct got_commitable *ct)
2774 {
2775 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
2776 }
2777 
2778 static const struct got_error *
2779 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
2780     struct got_tree_entry *te, struct got_commitable *ct)
2781 {
2782 	const struct got_error *err = NULL;
2783 
2784 	*new_te = NULL;
2785 
2786 	err = got_object_tree_entry_dup(new_te, te);
2787 	if (err)
2788 		goto done;
2789 
2790 	(*new_te)->mode = get_ct_file_mode(ct);
2791 
2792 	free((*new_te)->id);
2793 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2794 	if ((*new_te)->id == NULL) {
2795 		err = got_error_from_errno("got_object_id_dup");
2796 		goto done;
2797 	}
2798 done:
2799 	if (err && *new_te) {
2800 		got_object_tree_entry_close(*new_te);
2801 		*new_te = NULL;
2802 	}
2803 	return err;
2804 }
2805 
2806 static const struct got_error *
2807 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
2808     struct got_commitable *ct)
2809 {
2810 	const struct got_error *err = NULL;
2811 	char *ct_name;
2812 
2813 	 *new_te = NULL;
2814 
2815 	*new_te = calloc(1, sizeof(**new_te));
2816 	if (*new_te == NULL)
2817 		return got_error_from_errno("calloc");
2818 
2819 	ct_name = basename(ct->path);
2820 	if (ct_name == NULL) {
2821 		err = got_error_from_errno2("basename", ct->path);
2822 		goto done;
2823 	}
2824 	(*new_te)->name = strdup(ct_name);
2825 	if ((*new_te)->name == NULL) {
2826 		err = got_error_from_errno("strdup");
2827 		goto done;
2828 	}
2829 
2830 	(*new_te)->mode = get_ct_file_mode(ct);
2831 
2832 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2833 	if ((*new_te)->id == NULL) {
2834 		err = got_error_from_errno("got_object_id_dup");
2835 		goto done;
2836 	}
2837 done:
2838 	if (err && *new_te) {
2839 		got_object_tree_entry_close(*new_te);
2840 		*new_te = NULL;
2841 	}
2842 	return err;
2843 }
2844 
2845 static const struct got_error *
2846 insert_tree_entry(struct got_tree_entry *new_te,
2847     struct got_pathlist_head *paths)
2848 {
2849 	const struct got_error *err = NULL;
2850 	struct got_pathlist_entry *new_pe;
2851 
2852 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
2853 	if (err)
2854 		return err;
2855 	if (new_pe == NULL)
2856 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
2857 	return NULL;
2858 }
2859 
2860 static const struct got_error *
2861 report_ct_status(struct got_commitable *ct,
2862     got_worktree_status_cb status_cb, void *status_arg)
2863 {
2864 	const char *ct_path = ct->path;
2865 	while (ct_path[0] == '/')
2866 		ct_path++;
2867 	return (*status_cb)(status_arg, ct->status, ct_path, ct->blob_id, NULL);
2868 }
2869 
2870 static const struct got_error *
2871 match_modified_subtree(int *modified, struct got_tree_entry *te,
2872     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
2873 {
2874 	const struct got_error *err = NULL;
2875 	struct got_pathlist_entry *pe;
2876 	char *te_path;
2877 
2878 	*modified = 0;
2879 
2880 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
2881 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
2882 	    te->name) == -1)
2883 		return got_error_from_errno("asprintf");
2884 
2885 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2886 		struct got_commitable *ct = pe->data;
2887 		*modified = got_path_is_child(ct->in_repo_path, te_path,
2888 		    strlen(te_path));
2889 		 if (*modified)
2890 			break;
2891 	}
2892 
2893 	free(te_path);
2894 	return err;
2895 }
2896 
2897 static const struct got_error *
2898 match_deleted_or_modified_ct(struct got_commitable **ctp,
2899     struct got_tree_entry *te, const char *base_tree_path,
2900     struct got_pathlist_head *commitable_paths)
2901 {
2902 	const struct got_error *err = NULL;
2903 	struct got_pathlist_entry *pe;
2904 
2905 	*ctp = NULL;
2906 
2907 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2908 		struct got_commitable *ct = pe->data;
2909 		char *ct_name = NULL;
2910 		int path_matches;
2911 
2912 		if (ct->status != GOT_STATUS_MODIFY &&
2913 		    ct->status != GOT_STATUS_DELETE)
2914 			continue;
2915 
2916 		if (got_object_id_cmp(ct->base_blob_id, te->id) != 0)
2917 			continue;
2918 
2919 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
2920 		 if (err)
2921 			return err;
2922 		if (!path_matches)
2923 			continue;
2924 
2925 		ct_name = basename(pe->path);
2926 		if (ct_name == NULL)
2927 			return got_error_from_errno2("basename", pe->path);
2928 
2929 		if (strcmp(te->name, ct_name) != 0)
2930 			continue;
2931 
2932 		*ctp = ct;
2933 		break;
2934 	}
2935 
2936 	return err;
2937 }
2938 
2939 static const struct got_error *
2940 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
2941     const char *child_path, const char *path_base_tree,
2942     struct got_pathlist_head *commitable_paths,
2943     got_worktree_status_cb status_cb, void *status_arg,
2944     struct got_repository *repo)
2945 {
2946 	const struct got_error *err = NULL;
2947 	struct got_tree_entry *new_te;
2948 	char *subtree_path;
2949 
2950 	*new_tep = NULL;
2951 
2952 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
2953 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
2954 	    child_path) == -1)
2955 		return got_error_from_errno("asprintf");
2956 
2957 	new_te = calloc(1, sizeof(*new_te));
2958 	new_te->mode = S_IFDIR;
2959 	new_te->name = strdup(child_path);
2960 	if (new_te->name == NULL) {
2961 		err = got_error_from_errno("strdup");
2962 		got_object_tree_entry_close(new_te);
2963 		goto done;
2964 	}
2965 	err = write_tree(&new_te->id, NULL, subtree_path,
2966 	    commitable_paths, status_cb, status_arg, repo);
2967 	if (err) {
2968 		got_object_tree_entry_close(new_te);
2969 		goto done;
2970 	}
2971 done:
2972 	free(subtree_path);
2973 	if (err == NULL)
2974 		*new_tep = new_te;
2975 	return err;
2976 }
2977 
2978 static const struct got_error *
2979 write_tree(struct got_object_id **new_tree_id,
2980     struct got_tree_object *base_tree, const char *path_base_tree,
2981     struct got_pathlist_head *commitable_paths,
2982     got_worktree_status_cb status_cb, void *status_arg,
2983     struct got_repository *repo)
2984 {
2985 	const struct got_error *err = NULL;
2986 	const struct got_tree_entries *base_entries = NULL;
2987 	struct got_pathlist_head paths;
2988 	struct got_tree_entries new_tree_entries;
2989 	struct got_tree_entry *te, *new_te = NULL;
2990 	struct got_pathlist_entry *pe;
2991 
2992 	TAILQ_INIT(&paths);
2993 	new_tree_entries.nentries = 0;
2994 	SIMPLEQ_INIT(&new_tree_entries.head);
2995 
2996 	/* Insert, and recurse into, newly added entries first. */
2997 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2998 		struct got_commitable *ct = pe->data;
2999 		char *child_path = NULL, *slash;
3000 
3001 		if (ct->status != GOT_STATUS_ADD ||
3002 		    (ct->flags & GOT_COMMITABLE_ADDED))
3003 			continue;
3004 
3005 		 if (!got_path_is_child(pe->path, path_base_tree,
3006 		     strlen(path_base_tree)))
3007 			continue;
3008 
3009 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
3010 		    pe->path);
3011 		if (err)
3012 			goto done;
3013 
3014 		slash = strchr(child_path, '/');
3015 		if (slash == NULL) {
3016 			err = alloc_added_blob_tree_entry(&new_te, ct);
3017 			if (err)
3018 				goto done;
3019 			err = report_ct_status(ct, status_cb, status_arg);
3020 			if (err)
3021 				goto done;
3022 			ct->flags |= GOT_COMMITABLE_ADDED;
3023 			err = insert_tree_entry(new_te, &paths);
3024 			if (err)
3025 				goto done;
3026 		} else {
3027 			*slash = '\0'; /* trim trailing path components */
3028 			if (base_tree == NULL ||
3029 			    got_object_tree_find_entry(base_tree, child_path)
3030 			    == NULL) {
3031 				err = make_subtree_for_added_blob(&new_te,
3032 				    child_path, path_base_tree,
3033 				    commitable_paths, status_cb, status_arg,
3034 				    repo);
3035 				if (err)
3036 					goto done;
3037 				err = insert_tree_entry(new_te, &paths);
3038 				if (err)
3039 					goto done;
3040 			}
3041 		}
3042 	}
3043 
3044 	if (base_tree) {
3045 		/* Handle modified and deleted entries. */
3046 		base_entries = got_object_tree_get_entries(base_tree);
3047 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
3048 			struct got_commitable *ct = NULL;
3049 
3050 			if (S_ISDIR(te->mode)) {
3051 				int modified;
3052 				err = got_object_tree_entry_dup(&new_te, te);
3053 				if (err)
3054 					goto done;
3055 				err = match_modified_subtree(&modified, te,
3056 				    path_base_tree, commitable_paths);
3057 				if (err)
3058 					goto done;
3059 				/* Avoid recursion into unmodified subtrees. */
3060 				if (modified) {
3061 					free(new_te->id);
3062 					err = write_subtree(&new_te->id, te,
3063 					    path_base_tree, commitable_paths,
3064 					    status_cb, status_arg, repo);
3065 					if (err)
3066 						goto done;
3067 				}
3068 				err = insert_tree_entry(new_te, &paths);
3069 				if (err)
3070 					goto done;
3071 				continue;
3072 			}
3073 
3074 			err = match_deleted_or_modified_ct(&ct, te,
3075 			    path_base_tree, commitable_paths);
3076 			if (ct) {
3077 				/* NB: Deleted entries get dropped here. */
3078 				if (ct->status == GOT_STATUS_MODIFY) {
3079 					err = alloc_modified_blob_tree_entry(
3080 					    &new_te, te, ct);
3081 					if (err)
3082 						goto done;
3083 					err = insert_tree_entry(new_te, &paths);
3084 					if (err)
3085 						goto done;
3086 				}
3087 				err = report_ct_status(ct, status_cb,
3088 				    status_arg);
3089 				if (err)
3090 					goto done;
3091 			} else {
3092 				/* Entry is unchanged; just copy it. */
3093 				err = got_object_tree_entry_dup(&new_te, te);
3094 				if (err)
3095 					goto done;
3096 				err = insert_tree_entry(new_te, &paths);
3097 				if (err)
3098 					goto done;
3099 			}
3100 		}
3101 	}
3102 
3103 	/* Write new list of entries; deleted entries have been dropped. */
3104 	TAILQ_FOREACH(pe, &paths, entry) {
3105 		struct got_tree_entry *te = pe->data;
3106 		new_tree_entries.nentries++;
3107 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
3108 	}
3109 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
3110 done:
3111 	got_object_tree_entries_close(&new_tree_entries);
3112 	got_pathlist_free(&paths);
3113 	return err;
3114 }
3115 
3116 static const struct got_error *
3117 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
3118     struct got_object_id *new_base_commit_id, struct got_fileindex *fileindex)
3119 {
3120 	const struct got_error *err = NULL;
3121 	struct got_pathlist_entry *pe;
3122 
3123 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3124 		struct got_fileindex_entry *ie;
3125 		struct got_commitable *ct = pe->data;
3126 
3127 		ie = got_fileindex_entry_get(fileindex, pe->path);
3128 		if (ie) {
3129 			if (ct->status == GOT_STATUS_DELETE) {
3130 				got_fileindex_entry_remove(fileindex, ie);
3131 				got_fileindex_entry_free(ie);
3132 			} else
3133 				err = got_fileindex_entry_update(ie,
3134 				    ct->ondisk_path, ct->blob_id->sha1,
3135 				    new_base_commit_id->sha1, 1);
3136 		} else {
3137 			err = got_fileindex_entry_alloc(&ie,
3138 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
3139 			    new_base_commit_id->sha1);
3140 			if (err)
3141 				break;
3142 			err = got_fileindex_entry_add(fileindex, ie);
3143 			if (err)
3144 				break;
3145 		}
3146 	}
3147 	return err;
3148 }
3149 
3150 static const struct got_error *
3151 check_ct_out_of_date(struct got_commitable *ct, struct got_repository *repo,
3152 	struct got_object_id *head_commit_id)
3153 {
3154 	const struct got_error *err = NULL;
3155 	struct got_object_id *id_in_head = NULL, *id = NULL;
3156 	struct got_commit_object *commit = NULL;
3157 	char *path = NULL;
3158 	const char *ct_path = ct->in_repo_path;
3159 
3160 	while (ct_path[0] == '/')
3161 		ct_path++;
3162 
3163 	/*
3164 	 * Ensure that no modifications were made to files *and their parents*
3165 	 * in commits between the file's base commit and the branch head.
3166 	 *
3167 	 * Checking the parents is important for detecting conflicting tree
3168 	 * configurations (files or parent folders might have been moved,
3169 	 * deleted, added again, etc.). Such changes need to be merged with
3170 	 * local changes before a commit can occur.
3171 	 *
3172 	 * The implication is that the file's (parent) entry in the root
3173 	 * directory must have the same ID in all relevant commits.
3174 	 */
3175 	if (ct->status != GOT_STATUS_ADD) {
3176 		struct got_object_qid *pid;
3177 		char *slash;
3178 		struct got_object_id *root_entry_id = NULL;
3179 
3180 		/* Trivial case: base commit == head commit */
3181 		if (got_object_id_cmp(ct->base_commit_id, head_commit_id) == 0)
3182 			return NULL;
3183 
3184 		/* Compute the path to the root directory's entry. */
3185 		path = strdup(ct_path);
3186 		if (path == NULL) {
3187 			err = got_error_from_errno("strdup");
3188 			goto done;
3189 		}
3190 		slash = strchr(path, '/');
3191 		if (slash)
3192 			*slash = '\0';
3193 
3194 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
3195 		if (err)
3196 			goto done;
3197 
3198 		err = got_object_id_by_path(&root_entry_id, repo,
3199 		    head_commit_id, path);
3200 		if (err)
3201 			goto done;
3202 
3203 		pid = SIMPLEQ_FIRST(got_object_commit_get_parent_ids(commit));
3204 		while (pid) {
3205 			struct got_commit_object *pcommit;
3206 
3207 			err = got_object_id_by_path(&id, repo, pid->id, path);
3208 			if (err) {
3209 				if (err->code != GOT_ERR_NO_TREE_ENTRY)
3210 					goto done;
3211 				err = NULL;
3212 				break;
3213 			}
3214 
3215 			err = got_object_id_by_path(&id, repo, pid->id, path);
3216 			if (err)
3217 				goto done;
3218 
3219 			if (got_object_id_cmp(id, root_entry_id) != 0) {
3220 				err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
3221 				break;
3222 			}
3223 
3224 			if (got_object_id_cmp(pid->id, ct->base_commit_id) == 0)
3225 				break; /* all relevant commits scanned */
3226 
3227 			err = got_object_open_as_commit(&pcommit, repo,
3228 			    pid->id);
3229 			if (err)
3230 				goto done;
3231 
3232 			got_object_commit_close(commit);
3233 			commit = pcommit;
3234 			pid = SIMPLEQ_FIRST(got_object_commit_get_parent_ids(
3235 			    commit));
3236 		}
3237 	} else {
3238 		/* Require that added files don't exist in the branch head. */
3239 		err = got_object_id_by_path(&id_in_head, repo, head_commit_id,
3240 		    ct_path);
3241 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3242 			goto done;
3243 		err = id_in_head ? got_error(GOT_ERR_COMMIT_OUT_OF_DATE) : NULL;
3244 	}
3245 done:
3246 	if (commit)
3247 		got_object_commit_close(commit);
3248 	free(id_in_head);
3249 	free(id);
3250 	free(path);
3251 	return err;
3252 }
3253 
3254 const struct got_error *
3255 commit_worktree(struct got_object_id **new_commit_id,
3256     struct got_pathlist_head *commitable_paths,
3257     struct got_object_id *head_commit_id, struct got_worktree *worktree,
3258     const char *ondisk_path, const char *author, const char *committer,
3259     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3260     got_worktree_status_cb status_cb, void *status_arg,
3261     struct got_repository *repo)
3262 {
3263 	const struct got_error *err = NULL, *unlockerr = NULL;
3264 	struct got_pathlist_entry *pe;
3265 	const char *head_ref_name = NULL;
3266 	struct got_commit_object *head_commit = NULL;
3267 	struct got_reference *head_ref2 = NULL;
3268 	struct got_object_id *head_commit_id2 = NULL;
3269 	struct got_tree_object *head_tree = NULL;
3270 	struct got_object_id *new_tree_id = NULL;
3271 	struct got_object_id_queue parent_ids;
3272 	struct got_object_qid *pid = NULL;
3273 	char *logmsg = NULL;
3274 
3275 	*new_commit_id = NULL;
3276 
3277 	SIMPLEQ_INIT(&parent_ids);
3278 
3279 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
3280 	if (err)
3281 		goto done;
3282 
3283 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
3284 	if (err)
3285 		goto done;
3286 
3287 	if (commit_msg_cb != NULL) {
3288 		err = commit_msg_cb(commitable_paths, &logmsg, commit_arg);
3289 		if (err)
3290 			goto done;
3291 	}
3292 
3293 	if (logmsg == NULL || strlen(logmsg) == 0) {
3294 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
3295 		goto done;
3296 	}
3297 
3298 	/* Create blobs from added and modified files and record their IDs. */
3299 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3300 		struct got_commitable *ct = pe->data;
3301 		char *ondisk_path;
3302 
3303 		if (ct->status != GOT_STATUS_ADD &&
3304 		    ct->status != GOT_STATUS_MODIFY)
3305 			continue;
3306 
3307 		if (asprintf(&ondisk_path, "%s/%s",
3308 		    worktree->root_path, pe->path) == -1) {
3309 			err = got_error_from_errno("asprintf");
3310 			goto done;
3311 		}
3312 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
3313 		free(ondisk_path);
3314 		if (err)
3315 			goto done;
3316 	}
3317 
3318 	/* Recursively write new tree objects. */
3319 	err = write_tree(&new_tree_id, head_tree, "/", commitable_paths,
3320 	    status_cb, status_arg, repo);
3321 	if (err)
3322 		goto done;
3323 
3324 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
3325 	if (err)
3326 		goto done;
3327 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
3328 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
3329 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
3330 	got_object_qid_free(pid);
3331 	if (logmsg != NULL)
3332 		free(logmsg);
3333 	if (err)
3334 		goto done;
3335 
3336 	/* Check if a concurrent commit to our branch has occurred. */
3337 	head_ref_name = got_worktree_get_head_ref_name(worktree);
3338 	if (head_ref_name == NULL) {
3339 		err = got_error_from_errno("got_worktree_get_head_ref_name");
3340 		goto done;
3341 	}
3342 	/* Lock the reference here to prevent concurrent modification. */
3343 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
3344 	if (err)
3345 		goto done;
3346 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
3347 	if (err)
3348 		goto done;
3349 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
3350 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
3351 		goto done;
3352 	}
3353 	/* Update branch head in repository. */
3354 	err = got_ref_change_ref(head_ref2, *new_commit_id);
3355 	if (err)
3356 		goto done;
3357 	err = got_ref_write(head_ref2, repo);
3358 	if (err)
3359 		goto done;
3360 
3361 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
3362 	if (err)
3363 		goto done;
3364 
3365 	err = ref_base_commit(worktree, repo);
3366 	if (err)
3367 		goto done;
3368 done:
3369 	if (head_tree)
3370 		got_object_tree_close(head_tree);
3371 	if (head_commit)
3372 		got_object_commit_close(head_commit);
3373 	free(head_commit_id2);
3374 	if (head_ref2) {
3375 		unlockerr = got_ref_unlock(head_ref2);
3376 		if (unlockerr && err == NULL)
3377 			err = unlockerr;
3378 		got_ref_close(head_ref2);
3379 	}
3380 	return err;
3381 }
3382 
3383 const struct got_error *
3384 got_worktree_commit(struct got_object_id **new_commit_id,
3385     struct got_worktree *worktree, const char *ondisk_path,
3386     const char *author, const char *committer,
3387     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3388     got_worktree_status_cb status_cb, void *status_arg,
3389     struct got_repository *repo)
3390 {
3391 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
3392 	struct got_fileindex *fileindex = NULL;
3393 	char *fileindex_path = NULL, *relpath = NULL;
3394 	struct got_pathlist_head commitable_paths;
3395 	struct collect_commitables_arg cc_arg;
3396 	struct got_pathlist_entry *pe;
3397 	struct got_reference *head_ref = NULL;
3398 	struct got_object_id *head_commit_id = NULL;
3399 
3400 	*new_commit_id = NULL;
3401 
3402 	TAILQ_INIT(&commitable_paths);
3403 
3404 	err = lock_worktree(worktree, LOCK_EX);
3405 	if (err)
3406 		goto done;
3407 
3408 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
3409 	if (err)
3410 		goto done;
3411 
3412 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
3413 	if (err)
3414 		goto done;
3415 
3416 	if (ondisk_path) {
3417 		err = got_path_skip_common_ancestor(&relpath,
3418 		    worktree->root_path, ondisk_path);
3419 		if (err)
3420 			return err;
3421 	}
3422 
3423 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3424 	if (err)
3425 		goto done;
3426 
3427 	cc_arg.commitable_paths = &commitable_paths;
3428 	cc_arg.worktree = worktree;
3429 	cc_arg.repo = repo;
3430 	err = worktree_status(worktree, relpath ? relpath : "",
3431 	    fileindex, repo, collect_commitables, &cc_arg, NULL, NULL);
3432 	if (err)
3433 		goto done;
3434 
3435 	if (TAILQ_EMPTY(&commitable_paths)) {
3436 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
3437 		goto done;
3438 	}
3439 
3440 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3441 		struct got_commitable *ct = pe->data;
3442 		err = check_ct_out_of_date(ct, repo, head_commit_id);
3443 		if (err)
3444 			goto done;
3445 	}
3446 
3447 	err = commit_worktree(new_commit_id, &commitable_paths,
3448 	    head_commit_id, worktree, ondisk_path, author, committer,
3449 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
3450 	if (err)
3451 		goto done;
3452 
3453 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
3454 	    fileindex);
3455 	sync_err = sync_fileindex(fileindex, fileindex_path);
3456 	if (sync_err && err == NULL)
3457 		err = sync_err;
3458 done:
3459 	if (fileindex)
3460 		got_fileindex_free(fileindex);
3461 	free(fileindex_path);
3462 	free(relpath);
3463 	unlockerr = lock_worktree(worktree, LOCK_SH);
3464 	if (unlockerr && err == NULL)
3465 		err = unlockerr;
3466 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3467 		struct got_commitable *ct = pe->data;
3468 		free_commitable(ct);
3469 	}
3470 	got_pathlist_free(&commitable_paths);
3471 	return err;
3472 }
3473 
3474 const char *
3475 got_commitable_get_path(struct got_commitable *ct)
3476 {
3477 	return ct->path;
3478 }
3479 
3480 unsigned int
3481 got_commitable_get_status(struct got_commitable *ct)
3482 {
3483 	return ct->status;
3484 }
3485 
3486 struct check_rebase_ok_arg {
3487 	struct got_worktree *worktree;
3488 	struct got_repository *repo;
3489 	int rebase_in_progress;
3490 };
3491 
3492 static const struct got_error *
3493 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
3494 {
3495 	const struct got_error *err = NULL;
3496 	struct check_rebase_ok_arg *a = arg;
3497 	unsigned char status;
3498 	struct stat sb;
3499 	char *ondisk_path;
3500 
3501 	if (!a->rebase_in_progress) {
3502 		/* Reject rebase of a work tree with mixed base commits. */
3503 		if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
3504 		    SHA1_DIGEST_LENGTH))
3505 			return got_error(GOT_ERR_MIXED_COMMITS);
3506 	}
3507 
3508 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
3509 	    == -1)
3510 		return got_error_from_errno("asprintf");
3511 
3512 	/* Reject rebase of a work tree with modified or conflicted files. */
3513 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
3514 	free(ondisk_path);
3515 	if (err)
3516 		return err;
3517 
3518 	if (a->rebase_in_progress) {
3519 		if (status == GOT_STATUS_CONFLICT)
3520 			return got_error(GOT_ERR_CONFLICTS);
3521 	} else if (status != GOT_STATUS_NO_CHANGE)
3522 		return got_error(GOT_ERR_MODIFIED);
3523 
3524 	return NULL;
3525 }
3526 
3527 const struct got_error *
3528 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
3529     struct got_reference **tmp_branch, struct got_worktree *worktree,
3530     struct got_reference *branch, struct got_repository *repo)
3531 {
3532 	const struct got_error *err = NULL;
3533 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
3534 	char *branch_ref_name = NULL;
3535 	struct got_fileindex *fileindex = NULL;
3536 	char *fileindex_path = NULL;
3537 	struct check_rebase_ok_arg ok_arg;
3538 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
3539 
3540 	*new_base_branch_ref = NULL;
3541 	*tmp_branch = NULL;
3542 
3543 	err = lock_worktree(worktree, LOCK_EX);
3544 	if (err)
3545 		return err;
3546 
3547 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3548 	if (err)
3549 		goto done;
3550 
3551 	ok_arg.worktree = worktree;
3552 	ok_arg.repo = repo;
3553 	ok_arg.rebase_in_progress = 0;
3554 	err = got_fileindex_for_each_entry_safe(fileindex, check_rebase_ok,
3555 	    &ok_arg);
3556 	if (err)
3557 		goto done;
3558 
3559 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3560 	if (err)
3561 		goto done;
3562 
3563 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
3564 	if (err)
3565 		goto done;
3566 
3567 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
3568 	if (err)
3569 		goto done;
3570 
3571 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
3572 	    0);
3573 	if (err)
3574 		goto done;
3575 
3576 	err = got_ref_alloc_symref(new_base_branch_ref,
3577 	    new_base_branch_ref_name, wt_branch);
3578 	if (err)
3579 		goto done;
3580 	err = got_ref_write(*new_base_branch_ref, repo);
3581 	if (err)
3582 		goto done;
3583 
3584 	/* TODO Lock original branch's ref while rebasing? */
3585 
3586 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
3587 	if (err)
3588 		goto done;
3589 
3590 	err = got_ref_write(branch_ref, repo);
3591 	if (err)
3592 		goto done;
3593 
3594 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
3595 	    worktree->base_commit_id);
3596 	if (err)
3597 		goto done;
3598 	err = got_ref_write(*tmp_branch, repo);
3599 	if (err)
3600 		goto done;
3601 
3602 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
3603 	if (err)
3604 		goto done;
3605 done:
3606 	free(fileindex_path);
3607 	if (fileindex)
3608 		got_fileindex_free(fileindex);
3609 	free(tmp_branch_name);
3610 	free(new_base_branch_ref_name);
3611 	free(branch_ref_name);
3612 	if (branch_ref)
3613 		got_ref_close(branch_ref);
3614 	if (wt_branch)
3615 		got_ref_close(wt_branch);
3616 	if (err) {
3617 		if (*new_base_branch_ref) {
3618 			got_ref_close(*new_base_branch_ref);
3619 			*new_base_branch_ref = NULL;
3620 		}
3621 		if (*tmp_branch) {
3622 			got_ref_close(*tmp_branch);
3623 			*tmp_branch = NULL;
3624 		}
3625 		lock_worktree(worktree, LOCK_SH);
3626 	}
3627 	return err;
3628 }
3629 
3630 const struct got_error *
3631 got_worktree_rebase_continue(struct got_object_id **commit_id,
3632     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
3633     struct got_reference **branch, struct got_worktree *worktree,
3634     struct got_repository *repo)
3635 {
3636 	const struct got_error *err;
3637 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
3638 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
3639 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
3640 
3641 	*commit_id = NULL;
3642 
3643 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3644 	if (err)
3645 		return err;
3646 
3647 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
3648 	if (err)
3649 		goto done;
3650 
3651 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
3652 	if (err)
3653 		goto done;
3654 
3655 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
3656 	if (err)
3657 		goto done;
3658 
3659 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
3660 	if (err)
3661 		goto done;
3662 
3663 	err = got_ref_open(branch, repo,
3664 	    got_ref_get_symref_target(branch_ref), 0);
3665 	if (err)
3666 		goto done;
3667 
3668 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
3669 	if (err)
3670 		goto done;
3671 
3672 	err = got_ref_resolve(commit_id, repo, commit_ref);
3673 	if (err)
3674 		goto done;
3675 
3676 	err = got_ref_open(new_base_branch, repo,
3677 	    new_base_branch_ref_name, 0);
3678 	if (err)
3679 		goto done;
3680 
3681 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
3682 	if (err)
3683 		goto done;
3684 done:
3685 	free(commit_ref_name);
3686 	free(branch_ref_name);
3687 	if (commit_ref)
3688 		got_ref_close(commit_ref);
3689 	if (branch_ref)
3690 		got_ref_close(branch_ref);
3691 	if (err) {
3692 		free(*commit_id);
3693 		*commit_id = NULL;
3694 		if (*tmp_branch) {
3695 			got_ref_close(*tmp_branch);
3696 			*tmp_branch = NULL;
3697 		}
3698 		if (*new_base_branch) {
3699 			got_ref_close(*new_base_branch);
3700 			*new_base_branch = NULL;
3701 		}
3702 		if (*branch) {
3703 			got_ref_close(*branch);
3704 			*branch = NULL;
3705 		}
3706 	}
3707 	return err;
3708 }
3709 
3710 const struct got_error *
3711 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
3712 {
3713 	const struct got_error *err;
3714 	char *tmp_branch_name = NULL;
3715 
3716 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3717 	if (err)
3718 		return err;
3719 
3720 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
3721 	free(tmp_branch_name);
3722 	return NULL;
3723 }
3724 
3725 static const struct got_error *
3726 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
3727     char **logmsg, void *arg)
3728 {
3729 	struct got_commit_object *commit = arg;
3730 
3731 	*logmsg = strdup(got_object_commit_get_logmsg(commit));
3732 	if (*logmsg == NULL)
3733 		return got_error_from_errno("strdup");
3734 
3735 	return NULL;
3736 }
3737 
3738 static const struct got_error *
3739 rebase_status(void *arg, unsigned char status, const char *path,
3740     struct got_object_id *blob_id, struct got_object_id *commit_id)
3741 {
3742 	return NULL;
3743 }
3744 
3745 const struct got_error *
3746 got_worktree_rebase_merge_files(struct got_worktree *worktree,
3747     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
3748     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
3749     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
3750 {
3751 	const struct got_error *err;
3752 	struct got_fileindex *fileindex;
3753 	char *fileindex_path, *commit_ref_name = NULL;
3754 	struct got_reference *commit_ref = NULL;
3755 
3756 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
3757 
3758 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3759 	if (err)
3760 		return err;
3761 
3762 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
3763 	if (err)
3764 		goto done;
3765 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
3766 	if (err) {
3767 		if (err->code != GOT_ERR_NOT_REF)
3768 			goto done;
3769 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
3770 		if (err)
3771 			goto done;
3772 		err = got_ref_write(commit_ref, repo);
3773 		if (err)
3774 			goto done;
3775 	} else {
3776 		struct got_object_id *stored_id;
3777 		int cmp;
3778 
3779 		err = got_ref_resolve(&stored_id, repo, commit_ref);
3780 		if (err)
3781 			goto done;
3782 		cmp = got_object_id_cmp(commit_id, stored_id);
3783 		free(stored_id);
3784 		if (cmp != 0) {
3785 			err = got_error(GOT_ERR_REBASE_COMMITID);
3786 			goto done;
3787 		}
3788 	}
3789 
3790 	err = merge_files(worktree, fileindex, fileindex_path,
3791 	    parent_commit_id, commit_id, repo, progress_cb, progress_arg,
3792 	    cancel_cb, cancel_arg);
3793 done:
3794 	got_fileindex_free(fileindex);
3795 	free(fileindex_path);
3796 	if (commit_ref)
3797 		got_ref_close(commit_ref);
3798 	return err;
3799 }
3800 
3801 const struct got_error *
3802 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
3803     struct got_worktree *worktree, struct got_reference *tmp_branch,
3804     struct got_commit_object *orig_commit,
3805     struct got_object_id *orig_commit_id, struct got_repository *repo)
3806 {
3807 	const struct got_error *err, *sync_err;
3808 	struct got_pathlist_head commitable_paths;
3809 	struct collect_commitables_arg cc_arg;
3810 	struct got_fileindex *fileindex = NULL;
3811 	char *fileindex_path = NULL, *commit_ref_name = NULL;
3812 	struct got_reference *head_ref = NULL;
3813 	struct got_object_id *head_commit_id = NULL;
3814 	struct got_reference *commit_ref = NULL;
3815 	struct got_object_id *commit_id = NULL;
3816 
3817 	TAILQ_INIT(&commitable_paths);
3818 	*new_commit_id = NULL;
3819 
3820 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
3821 
3822 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
3823 	if (err)
3824 		return err;
3825 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
3826 	if (err)
3827 		goto done;
3828 	err = got_ref_resolve(&commit_id, repo, commit_ref);
3829 	if (err)
3830 		goto done;
3831 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
3832 		err = got_error(GOT_ERR_REBASE_COMMITID);
3833 		goto done;
3834 	}
3835 
3836 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3837 	if (err)
3838 		goto done;
3839 
3840 	cc_arg.commitable_paths = &commitable_paths;
3841 	cc_arg.worktree = worktree;
3842 	cc_arg.repo = repo;
3843 	err = worktree_status(worktree, "", fileindex, repo,
3844 	    collect_commitables, &cc_arg, NULL, NULL);
3845 	if (err)
3846 		goto done;
3847 
3848 	if (TAILQ_EMPTY(&commitable_paths)) {
3849 		/* No-op change; commit will be elided. */
3850 		err = got_ref_delete(commit_ref, repo);
3851 		if (err)
3852 			goto done;
3853 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
3854 		goto done;
3855 	}
3856 
3857 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
3858 	if (err)
3859 		goto done;
3860 
3861 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
3862 	if (err)
3863 		goto done;
3864 
3865 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
3866 	    worktree, NULL, got_object_commit_get_author(orig_commit),
3867 	    got_object_commit_get_committer(orig_commit),
3868 	    collect_rebase_commit_msg, orig_commit,
3869 	    rebase_status, NULL, repo);
3870 	if (err)
3871 		goto done;
3872 
3873 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
3874 	if (err)
3875 		goto done;
3876 
3877 	err = got_ref_delete(commit_ref, repo);
3878 	if (err)
3879 		goto done;
3880 
3881 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
3882 	    fileindex);
3883 	sync_err = sync_fileindex(fileindex, fileindex_path);
3884 	if (sync_err && err == NULL)
3885 		err = sync_err;
3886 done:
3887 	if (fileindex)
3888 		got_fileindex_free(fileindex);
3889 	free(fileindex_path);
3890 	free(commit_ref_name);
3891 	if (commit_ref)
3892 		got_ref_close(commit_ref);
3893 	free(head_commit_id);
3894 	if (head_ref)
3895 		got_ref_close(head_ref);
3896 	if (err) {
3897 		free(*new_commit_id);
3898 		*new_commit_id = NULL;
3899 	}
3900 	return err;
3901 }
3902 
3903 const struct got_error *
3904 got_worktree_rebase_postpone(struct got_worktree *worktree)
3905 {
3906 	return lock_worktree(worktree, LOCK_SH);
3907 }
3908 
3909 static const struct got_error *
3910 delete_ref(const char *name, struct got_repository *repo)
3911 {
3912 	const struct got_error *err;
3913 	struct got_reference *ref;
3914 
3915 	err = got_ref_open(&ref, repo, name, 0);
3916 	if (err) {
3917 		if (err->code == GOT_ERR_NOT_REF)
3918 			return NULL;
3919 		return err;
3920 	}
3921 
3922 	err = got_ref_delete(ref, repo);
3923 	got_ref_close(ref);
3924 	return err;
3925 }
3926 
3927 static const struct got_error *
3928 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
3929 {
3930 	const struct got_error *err;
3931 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
3932 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
3933 
3934 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3935 	if (err)
3936 		goto done;
3937 	err = delete_ref(tmp_branch_name, repo);
3938 	if (err)
3939 		goto done;
3940 
3941 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
3942 	if (err)
3943 		goto done;
3944 	err = delete_ref(new_base_branch_ref_name, repo);
3945 	if (err)
3946 		goto done;
3947 
3948 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
3949 	if (err)
3950 		goto done;
3951 	err = delete_ref(branch_ref_name, repo);
3952 	if (err)
3953 		goto done;
3954 
3955 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
3956 	if (err)
3957 		goto done;
3958 	err = delete_ref(commit_ref_name, repo);
3959 	if (err)
3960 		goto done;
3961 
3962 done:
3963 	free(tmp_branch_name);
3964 	free(new_base_branch_ref_name);
3965 	free(branch_ref_name);
3966 	free(commit_ref_name);
3967 	return err;
3968 }
3969 
3970 const struct got_error *
3971 got_worktree_rebase_complete(struct got_worktree *worktree,
3972     struct got_reference *new_base_branch, struct got_reference *tmp_branch,
3973     struct got_reference *rebased_branch,
3974     struct got_repository *repo)
3975 {
3976 	const struct got_error *err, *unlockerr;
3977 	struct got_object_id *new_head_commit_id = NULL;
3978 
3979 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
3980 	if (err)
3981 		return err;
3982 
3983 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
3984 	if (err)
3985 		goto done;
3986 
3987 	err = got_ref_write(rebased_branch, repo);
3988 	if (err)
3989 		goto done;
3990 
3991 	err = got_worktree_set_head_ref(worktree, rebased_branch);
3992 	if (err)
3993 		goto done;
3994 
3995 	err = delete_rebase_refs(worktree, repo);
3996 done:
3997 	free(new_head_commit_id);
3998 	unlockerr = lock_worktree(worktree, LOCK_SH);
3999 	if (unlockerr && err == NULL)
4000 		err = unlockerr;
4001 	return err;
4002 }
4003 
4004 struct collect_revertible_paths_arg {
4005 	struct got_pathlist_head *revertible_paths;
4006 	struct got_worktree *worktree;
4007 };
4008 
4009 static const struct got_error *
4010 collect_revertible_paths(void *arg, unsigned char status, const char *relpath,
4011     struct got_object_id *blob_id, struct got_object_id *commit_id)
4012 {
4013 	struct collect_revertible_paths_arg *a = arg;
4014 	const struct got_error *err = NULL;
4015 	struct got_pathlist_entry *new = NULL;
4016 	char *path = NULL;
4017 
4018 	if (status != GOT_STATUS_ADD &&
4019 	    status != GOT_STATUS_DELETE &&
4020 	    status != GOT_STATUS_MODIFY &&
4021 	    status != GOT_STATUS_CONFLICT &&
4022 	    status != GOT_STATUS_MISSING)
4023 		return NULL;
4024 
4025 	if (asprintf(&path, "%s/%s", a->worktree->root_path, relpath) == -1)
4026 		return got_error_from_errno("asprintf");
4027 
4028 	err = got_pathlist_insert(&new, a->revertible_paths, path, NULL);
4029 	if (err || new == NULL)
4030 		free(path);
4031 	return err;
4032 }
4033 
4034 const struct got_error *
4035 got_worktree_rebase_abort(struct got_worktree *worktree,
4036     struct got_repository *repo, struct got_reference *new_base_branch,
4037      got_worktree_checkout_cb progress_cb, void *progress_arg)
4038 {
4039 	const struct got_error *err, *unlockerr, *sync_err;
4040 	struct got_reference *resolved = NULL;
4041 	struct got_object_id *commit_id = NULL;
4042 	struct got_fileindex *fileindex = NULL;
4043 	char *fileindex_path = NULL;
4044 	struct got_pathlist_head revertible_paths;
4045 	struct got_pathlist_entry *pe;
4046 	struct collect_revertible_paths_arg crp_arg;
4047 	struct got_object_id *tree_id = NULL;
4048 
4049 	TAILQ_INIT(&revertible_paths);
4050 
4051 	err = lock_worktree(worktree, LOCK_EX);
4052 	if (err)
4053 		return err;
4054 
4055 	err = got_ref_open(&resolved, repo,
4056 	    got_ref_get_symref_target(new_base_branch), 0);
4057 	if (err)
4058 		goto done;
4059 
4060 	err = got_worktree_set_head_ref(worktree, resolved);
4061 	if (err)
4062 		goto done;
4063 
4064 	/*
4065 	 * XXX commits to the base branch could have happened while
4066 	 * we were busy rebasing; should we store the original commit ID
4067 	 * when rebase begins and read it back here?
4068 	 */
4069 	err = got_ref_resolve(&commit_id, repo, resolved);
4070 	if (err)
4071 		goto done;
4072 
4073 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
4074 	if (err)
4075 		goto done;
4076 
4077 	err = got_object_id_by_path(&tree_id, repo,
4078 	    worktree->base_commit_id, worktree->path_prefix);
4079 	if (err)
4080 		goto done;
4081 
4082 	err = delete_rebase_refs(worktree, repo);
4083 	if (err)
4084 		goto done;
4085 
4086 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4087 	if (err)
4088 		goto done;
4089 
4090 	crp_arg.revertible_paths = &revertible_paths;
4091 	crp_arg.worktree = worktree;
4092 	err = worktree_status(worktree, "", fileindex, repo,
4093 	    collect_revertible_paths, &crp_arg, NULL, NULL);
4094 	if (err)
4095 		goto done;
4096 
4097 	TAILQ_FOREACH(pe, &revertible_paths, entry) {
4098 		err = revert_file(worktree, fileindex, pe->path,
4099 		    progress_cb, progress_arg, repo);
4100 		if (err)
4101 			goto sync;
4102 	}
4103 
4104 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
4105 	    repo, progress_cb, progress_arg, NULL, NULL);
4106 sync:
4107 	sync_err = sync_fileindex(fileindex, fileindex_path);
4108 	if (sync_err && err == NULL)
4109 		err = sync_err;
4110 done:
4111 	got_ref_close(resolved);
4112 	free(tree_id);
4113 	free(commit_id);
4114 	if (fileindex)
4115 		got_fileindex_free(fileindex);
4116 	free(fileindex_path);
4117 	TAILQ_FOREACH(pe, &revertible_paths, entry)
4118 		free((char *)pe->path);
4119 	got_pathlist_free(&revertible_paths);
4120 
4121 	unlockerr = lock_worktree(worktree, LOCK_SH);
4122 	if (unlockerr && err == NULL)
4123 		err = unlockerr;
4124 	return err;
4125 }