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