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_path(path, 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 (fstat(fd, &sb) != 0) {
146 		err = got_error_from_errno2("fstat", 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_path(path, GOT_ERR_WORKTREE_META));
159 		goto done;
160 	}
161 	if ((*content)[sb.st_size - 1] != '\n') {
162 		err = got_error_path(path, 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_msg(GOT_ERR_WORKTREE_META,
359 		    "could not parse work tree format version number");
360 		goto done;
361 	}
362 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
363 		err = got_error(GOT_ERR_WORKTREE_VERS);
364 		goto done;
365 	}
366 
367 	*worktree = calloc(1, sizeof(**worktree));
368 	if (*worktree == NULL) {
369 		err = got_error_from_errno("calloc");
370 		goto done;
371 	}
372 	(*worktree)->lockfd = -1;
373 
374 	(*worktree)->root_path = strdup(path);
375 	if ((*worktree)->root_path == NULL) {
376 		err = got_error_from_errno("strdup");
377 		goto done;
378 	}
379 	err = read_meta_file(&(*worktree)->repo_path, path_got,
380 	    GOT_WORKTREE_REPOSITORY);
381 	if (err)
382 		goto done;
383 
384 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
385 	    GOT_WORKTREE_PATH_PREFIX);
386 	if (err)
387 		goto done;
388 
389 	err = read_meta_file(&base_commit_id_str, path_got,
390 	    GOT_WORKTREE_BASE_COMMIT);
391 	if (err)
392 		goto done;
393 
394 	err = read_meta_file(&uuidstr, path_got, GOT_WORKTREE_UUID);
395 	if (err)
396 		goto done;
397 	uuid_from_string(uuidstr, &(*worktree)->uuid, &uuid_status);
398 	if (uuid_status != uuid_s_ok) {
399 		err = got_error_uuid(uuid_status);
400 		goto done;
401 	}
402 
403 	err = got_repo_open(&repo, (*worktree)->repo_path);
404 	if (err)
405 		goto done;
406 
407 	err = got_object_resolve_id_str(&(*worktree)->base_commit_id, repo,
408 	    base_commit_id_str);
409 	if (err)
410 		goto done;
411 
412 	err = read_meta_file(&(*worktree)->head_ref_name, path_got,
413 	    GOT_WORKTREE_HEAD_REF);
414 done:
415 	if (repo)
416 		got_repo_close(repo);
417 	free(path_got);
418 	free(path_lock);
419 	free(base_commit_id_str);
420 	free(uuidstr);
421 	free(formatstr);
422 	if (err) {
423 		if (fd != -1)
424 			close(fd);
425 		if (*worktree != NULL)
426 			got_worktree_close(*worktree);
427 		*worktree = NULL;
428 	} else
429 		(*worktree)->lockfd = fd;
430 
431 	return err;
432 }
433 
434 const struct got_error *
435 got_worktree_open(struct got_worktree **worktree, const char *path)
436 {
437 	const struct got_error *err = NULL;
438 
439 	do {
440 		err = open_worktree(worktree, path);
441 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT))
442 			return err;
443 		if (*worktree)
444 			return NULL;
445 		path = dirname(path);
446 		if (path == NULL)
447 			return got_error_from_errno2("dirname", path);
448 	} while (!((path[0] == '.' || path[0] == '/') && path[1] == '\0'));
449 
450 	return got_error(GOT_ERR_NOT_WORKTREE);
451 }
452 
453 const struct got_error *
454 got_worktree_close(struct got_worktree *worktree)
455 {
456 	const struct got_error *err = NULL;
457 	free(worktree->root_path);
458 	free(worktree->repo_path);
459 	free(worktree->path_prefix);
460 	free(worktree->base_commit_id);
461 	free(worktree->head_ref_name);
462 	if (worktree->lockfd != -1)
463 		if (close(worktree->lockfd) != 0)
464 			err = got_error_from_errno2("close",
465 			    got_worktree_get_root_path(worktree));
466 	free(worktree);
467 	return err;
468 }
469 
470 const char *
471 got_worktree_get_root_path(struct got_worktree *worktree)
472 {
473 	return worktree->root_path;
474 }
475 
476 const char *
477 got_worktree_get_repo_path(struct got_worktree *worktree)
478 {
479 	return worktree->repo_path;
480 }
481 
482 const char *
483 got_worktree_get_path_prefix(struct got_worktree *worktree)
484 {
485 	return worktree->path_prefix;
486 }
487 
488 const struct got_error *
489 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
490     const char *path_prefix)
491 {
492 	char *absprefix = NULL;
493 
494 	if (!got_path_is_absolute(path_prefix)) {
495 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
496 			return got_error_from_errno("asprintf");
497 	}
498 	*match = (strcmp(absprefix ? absprefix : path_prefix,
499 	    worktree->path_prefix) == 0);
500 	free(absprefix);
501 	return NULL;
502 }
503 
504 const char *
505 got_worktree_get_head_ref_name(struct got_worktree *worktree)
506 {
507 	return worktree->head_ref_name;
508 }
509 
510 const struct got_error *
511 got_worktree_set_head_ref(struct got_worktree *worktree,
512     struct got_reference *head_ref)
513 {
514 	const struct got_error *err = NULL;
515 	char *path_got = NULL, *head_ref_name = NULL;
516 
517 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
518 	    GOT_WORKTREE_GOT_DIR) == -1) {
519 		err = got_error_from_errno("asprintf");
520 		path_got = NULL;
521 		goto done;
522 	}
523 
524 	head_ref_name = strdup(got_ref_get_name(head_ref));
525 	if (head_ref_name == NULL) {
526 		err = got_error_from_errno("strdup");
527 		goto done;
528 	}
529 
530 	err = write_head_ref(path_got, head_ref);
531 	if (err)
532 		goto done;
533 
534 	free(worktree->head_ref_name);
535 	worktree->head_ref_name = head_ref_name;
536 done:
537 	free(path_got);
538 	if (err)
539 		free(head_ref_name);
540 	return err;
541 }
542 
543 struct got_object_id *
544 got_worktree_get_base_commit_id(struct got_worktree *worktree)
545 {
546 	return worktree->base_commit_id;
547 }
548 
549 const struct got_error *
550 got_worktree_set_base_commit_id(struct got_worktree *worktree,
551     struct got_repository *repo, struct got_object_id *commit_id)
552 {
553 	const struct got_error *err;
554 	struct got_object *obj = NULL;
555 	char *id_str = NULL;
556 	char *path_got = NULL;
557 
558 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
559 	    GOT_WORKTREE_GOT_DIR) == -1) {
560 		err = got_error_from_errno("asprintf");
561 		path_got = NULL;
562 		goto done;
563 	}
564 
565 	err = got_object_open(&obj, repo, commit_id);
566 	if (err)
567 		return err;
568 
569 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
570 		err = got_error(GOT_ERR_OBJ_TYPE);
571 		goto done;
572 	}
573 
574 	/* Record our base commit. */
575 	err = got_object_id_str(&id_str, commit_id);
576 	if (err)
577 		goto done;
578 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
579 	if (err)
580 		goto done;
581 
582 	free(worktree->base_commit_id);
583 	worktree->base_commit_id = got_object_id_dup(commit_id);
584 	if (worktree->base_commit_id == NULL) {
585 		err = got_error_from_errno("got_object_id_dup");
586 		goto done;
587 	}
588 done:
589 	if (obj)
590 		got_object_close(obj);
591 	free(id_str);
592 	free(path_got);
593 	return err;
594 }
595 
596 static const struct got_error *
597 lock_worktree(struct got_worktree *worktree, int operation)
598 {
599 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
600 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
601 		    : got_error_from_errno2("flock",
602 		    got_worktree_get_root_path(worktree)));
603 	return NULL;
604 }
605 
606 static const struct got_error *
607 add_dir_on_disk(struct got_worktree *worktree, const char *path)
608 {
609 	const struct got_error *err = NULL;
610 	char *abspath;
611 
612 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
613 		return got_error_from_errno("asprintf");
614 
615 	err = got_path_mkdir(abspath);
616 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
617 		struct stat sb;
618 		err = NULL;
619 		if (lstat(abspath, &sb) == -1) {
620 			err = got_error_from_errno2("lstat", abspath);
621 		} else if (!S_ISDIR(sb.st_mode)) {
622 			/* TODO directory is obstructed; do something */
623 			err = got_error(GOT_ERR_FILE_OBSTRUCTED);
624 		}
625 	}
626 	free(abspath);
627 	return err;
628 }
629 
630 static const struct got_error *
631 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
632 {
633 	const struct got_error *err = NULL;
634 	uint8_t fbuf1[8192];
635 	uint8_t fbuf2[8192];
636 	size_t flen1 = 0, flen2 = 0;
637 
638 	*same = 1;
639 
640 	for (;;) {
641 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
642 		if (flen1 == 0 && ferror(f1)) {
643 			err = got_error_from_errno("fread");
644 			break;
645 		}
646 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
647 		if (flen2 == 0 && ferror(f2)) {
648 			err = got_error_from_errno("fread");
649 			break;
650 		}
651 		if (flen1 == 0) {
652 			if (flen2 != 0)
653 				*same = 0;
654 			break;
655 		} else if (flen2 == 0) {
656 			if (flen1 != 0)
657 				*same = 0;
658 			break;
659 		} else if (flen1 == flen2) {
660 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
661 				*same = 0;
662 				break;
663 			}
664 		} else {
665 			*same = 0;
666 			break;
667 		}
668 	}
669 
670 	return err;
671 }
672 
673 static const struct got_error *
674 check_files_equal(int *same, const char *f1_path, const char *f2_path)
675 {
676 	const struct got_error *err = NULL;
677 	struct stat sb;
678 	size_t size1, size2;
679 	FILE *f1 = NULL, *f2 = NULL;
680 
681 	*same = 1;
682 
683 	if (lstat(f1_path, &sb) != 0) {
684 		err = got_error_from_errno2("lstat", f1_path);
685 		goto done;
686 	}
687 	size1 = sb.st_size;
688 
689 	if (lstat(f2_path, &sb) != 0) {
690 		err = got_error_from_errno2("lstat", f2_path);
691 		goto done;
692 	}
693 	size2 = sb.st_size;
694 
695 	if (size1 != size2) {
696 		*same = 0;
697 		return NULL;
698 	}
699 
700 	f1 = fopen(f1_path, "r");
701 	if (f1 == NULL)
702 		return got_error_from_errno2("open", f1_path);
703 
704 	f2 = fopen(f2_path, "r");
705 	if (f2 == NULL) {
706 		err = got_error_from_errno2("open", f2_path);
707 		goto done;
708 	}
709 
710 	err = check_file_contents_equal(same, f1, f2);
711 done:
712 	if (f1 && fclose(f1) != 0 && err == NULL)
713 		err = got_error_from_errno("fclose");
714 	if (f2 && fclose(f2) != 0 && err == NULL)
715 		err = got_error_from_errno("fclose");
716 
717 	return err;
718 }
719 
720 /*
721  * Perform a 3-way merge where blob_orig acts as the common ancestor,
722  * blob_deriv acts as the first derived version, and the file on disk
723  * acts as the second derived version.
724  */
725 static const struct got_error *
726 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
727     struct got_blob_object *blob_orig, const char *ondisk_path,
728     const char *path, uint16_t st_mode, struct got_blob_object *blob_deriv,
729     struct got_object_id *deriv_base_commit_id,
730     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
731     void *progress_arg)
732 {
733 	const struct got_error *err = NULL;
734 	int merged_fd = -1;
735 	FILE *f_deriv = NULL, *f_orig = NULL;
736 	char *blob_deriv_path = NULL, *blob_orig_path = NULL;
737 	char *merged_path = NULL, *base_path = NULL;
738 	char *id_str = NULL;
739 	char *label_deriv = NULL;
740 	int overlapcnt = 0;
741 	char *parent;
742 
743 	*local_changes_subsumed = 0;
744 
745 	parent = dirname(ondisk_path);
746 	if (parent == NULL)
747 		return got_error_from_errno2("dirname", ondisk_path);
748 
749 	if (asprintf(&base_path, "%s/got-merged", parent) == -1)
750 		return got_error_from_errno("asprintf");
751 
752 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
753 	if (err)
754 		goto done;
755 
756 	free(base_path);
757 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
758 		err = got_error_from_errno("asprintf");
759 		base_path = NULL;
760 		goto done;
761 	}
762 
763 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path);
764 	if (err)
765 		goto done;
766 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
767 	    blob_deriv);
768 	if (err)
769 		goto done;
770 
771 	free(base_path);
772 	if (asprintf(&base_path, "%s/got-merge-blob-orig", parent) == -1) {
773 		err = got_error_from_errno("asprintf");
774 		base_path = NULL;
775 		goto done;
776 	}
777 
778 	err = got_opentemp_named(&blob_orig_path, &f_orig, base_path);
779 	if (err)
780 		goto done;
781 	if (blob_orig) {
782 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
783 		    blob_orig);
784 		if (err)
785 			goto done;
786 	} else {
787 		/*
788 		 * If the file has no blob, this is an "add vs add" conflict,
789 		 * and we simply use an empty ancestor file to make both files
790 		 * appear in the merged result in their entirety.
791 		 */
792 	}
793 
794 	err = got_object_id_str(&id_str, deriv_base_commit_id);
795 	if (err)
796 		goto done;
797 	if (asprintf(&label_deriv, "commit %s", id_str) == -1) {
798 		err = got_error_from_errno("asprintf");
799 		goto done;
800 	}
801 
802 	err = got_merge_diff3(&overlapcnt, merged_fd, blob_deriv_path,
803 	    blob_orig_path, ondisk_path, label_deriv, path);
804 	if (err)
805 		goto done;
806 
807 	err = (*progress_cb)(progress_arg,
808 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
809 	if (err)
810 		goto done;
811 
812 	if (fsync(merged_fd) != 0) {
813 		err = got_error_from_errno("fsync");
814 		goto done;
815 	}
816 
817 	/* Check if a clean merge has subsumed all local changes. */
818 	if (overlapcnt == 0) {
819 		err = check_files_equal(local_changes_subsumed, blob_deriv_path,
820 		    merged_path);
821 		if (err)
822 			goto done;
823 	}
824 
825 	if (chmod(merged_path, st_mode) != 0) {
826 		err = got_error_from_errno2("chmod", merged_path);
827 		goto done;
828 	}
829 
830 	if (rename(merged_path, ondisk_path) != 0) {
831 		err = got_error_from_errno3("rename", merged_path,
832 		    ondisk_path);
833 		unlink(merged_path);
834 		goto done;
835 	}
836 
837 done:
838 	if (merged_fd != -1 && close(merged_fd) != 0 && err == NULL)
839 		err = got_error_from_errno("close");
840 	if (f_deriv && fclose(f_deriv) != 0 && err == NULL)
841 		err = got_error_from_errno("fclose");
842 	if (f_orig && fclose(f_orig) != 0 && err == NULL)
843 		err = got_error_from_errno("fclose");
844 	free(merged_path);
845 	free(base_path);
846 	if (blob_deriv_path) {
847 		unlink(blob_deriv_path);
848 		free(blob_deriv_path);
849 	}
850 	if (blob_orig_path) {
851 		unlink(blob_orig_path);
852 		free(blob_orig_path);
853 	}
854 	free(id_str);
855 	free(label_deriv);
856 	return err;
857 }
858 
859 static const struct got_error *
860 update_blob_fileindex_entry(struct got_worktree *worktree,
861     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
862     const char *ondisk_path, const char *path, struct got_blob_object *blob,
863     int update_timestamps)
864 {
865 	const struct got_error *err = NULL;
866 
867 	if (ie == NULL)
868 		ie = got_fileindex_entry_get(fileindex, path, strlen(path));
869 	if (ie)
870 		err = got_fileindex_entry_update(ie, ondisk_path,
871 		    blob->id.sha1, worktree->base_commit_id->sha1,
872 		    update_timestamps);
873 	else {
874 		struct got_fileindex_entry *new_ie;
875 		err = got_fileindex_entry_alloc(&new_ie, ondisk_path,
876 		    path, blob->id.sha1, worktree->base_commit_id->sha1);
877 		if (!err)
878 			err = got_fileindex_entry_add(fileindex, new_ie);
879 	}
880 	return err;
881 }
882 
883 static const struct got_error *
884 install_blob(struct got_worktree *worktree, const char *ondisk_path,
885    const char *path, uint16_t te_mode, uint16_t st_mode,
886    struct got_blob_object *blob, int restoring_missing_file,
887    int reverting_versioned_file, struct got_repository *repo,
888    got_worktree_checkout_cb progress_cb, void *progress_arg)
889 {
890 	const struct got_error *err = NULL;
891 	int fd = -1;
892 	size_t len, hdrlen;
893 	int update = 0;
894 	char *tmppath = NULL;
895 
896 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
897 	    GOT_DEFAULT_FILE_MODE);
898 	if (fd == -1) {
899 		if (errno == ENOENT) {
900 			char *parent = dirname(path);
901 			if (parent == NULL)
902 				return got_error_from_errno2("dirname", path);
903 			err = add_dir_on_disk(worktree, parent);
904 			if (err)
905 				return err;
906 			fd = open(ondisk_path,
907 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
908 			    GOT_DEFAULT_FILE_MODE);
909 			if (fd == -1)
910 				return got_error_from_errno2("open",
911 				    ondisk_path);
912 		} else if (errno == EEXIST) {
913 			if (!S_ISREG(st_mode)) {
914 				/* TODO file is obstructed; do something */
915 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
916 				goto done;
917 			} else {
918 				err = got_opentemp_named_fd(&tmppath, &fd,
919 				    ondisk_path);
920 				if (err)
921 					goto done;
922 				update = 1;
923 			}
924 		} else
925 			return got_error_from_errno2("open", ondisk_path);
926 	}
927 
928 	if (restoring_missing_file)
929 		err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING, path);
930 	else if (reverting_versioned_file)
931 		err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT, path);
932 	else
933 		err = (*progress_cb)(progress_arg,
934 		    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
935 	if (err)
936 		goto done;
937 
938 	hdrlen = got_object_blob_get_hdrlen(blob);
939 	do {
940 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
941 		err = got_object_blob_read_block(&len, blob);
942 		if (err)
943 			break;
944 		if (len > 0) {
945 			/* Skip blob object header first time around. */
946 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
947 			if (outlen == -1) {
948 				err = got_error_from_errno("write");
949 				goto done;
950 			} else if (outlen != len - hdrlen) {
951 				err = got_error(GOT_ERR_IO);
952 				goto done;
953 			}
954 			hdrlen = 0;
955 		}
956 	} while (len != 0);
957 
958 	if (fsync(fd) != 0) {
959 		err = got_error_from_errno("fsync");
960 		goto done;
961 	}
962 
963 	if (update) {
964 		if (rename(tmppath, ondisk_path) != 0) {
965 			err = got_error_from_errno3("rename", tmppath,
966 			    ondisk_path);
967 			unlink(tmppath);
968 			goto done;
969 		}
970 	}
971 
972 	if (te_mode & S_IXUSR) {
973 		if (chmod(ondisk_path, st_mode | S_IXUSR) == -1) {
974 			err = got_error_from_errno2("chmod", ondisk_path);
975 			goto done;
976 		}
977 	} else {
978 		if (chmod(ondisk_path, st_mode & ~S_IXUSR) == -1) {
979 			err = got_error_from_errno2("chmod", ondisk_path);
980 			goto done;
981 		}
982 	}
983 
984 done:
985 	if (fd != -1 && close(fd) != 0 && err == NULL)
986 		err = got_error_from_errno("close");
987 	free(tmppath);
988 	return err;
989 }
990 
991 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
992 static const struct got_error *
993 get_modified_file_content_status(unsigned char *status, FILE *f)
994 {
995 	const struct got_error *err = NULL;
996 	const char *markers[3] = {
997 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
998 		GOT_DIFF_CONFLICT_MARKER_SEP,
999 		GOT_DIFF_CONFLICT_MARKER_END
1000 	};
1001 	int i = 0;
1002 	char *line;
1003 	size_t len;
1004 	const char delim[3] = {'\0', '\0', '\0'};
1005 
1006 	while (*status == GOT_STATUS_MODIFY) {
1007 		line = fparseln(f, &len, NULL, delim, 0);
1008 		if (line == NULL) {
1009 			if (feof(f))
1010 				break;
1011 			err = got_ferror(f, GOT_ERR_IO);
1012 			break;
1013 		}
1014 
1015 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1016 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1017 			    == 0)
1018 				*status = GOT_STATUS_CONFLICT;
1019 			else
1020 				i++;
1021 		}
1022 	}
1023 
1024 	return err;
1025 }
1026 
1027 static int
1028 stat_info_differs(struct got_fileindex_entry *ie, struct stat *sb)
1029 {
1030 	return !(ie->ctime_sec == sb->st_ctime &&
1031 	    ie->ctime_nsec == sb->st_ctimensec &&
1032 	    ie->mtime_sec == sb->st_mtime &&
1033 	    ie->mtime_nsec == sb->st_mtimensec &&
1034 	    ie->size == (sb->st_size & 0xffffffff));
1035 }
1036 
1037 static const struct got_error *
1038 get_file_status(unsigned char *status, struct stat *sb,
1039     struct got_fileindex_entry *ie, const char *abspath,
1040     struct got_repository *repo)
1041 {
1042 	const struct got_error *err = NULL;
1043 	struct got_object_id id;
1044 	size_t hdrlen;
1045 	FILE *f = NULL;
1046 	uint8_t fbuf[8192];
1047 	struct got_blob_object *blob = NULL;
1048 	size_t flen, blen;
1049 
1050 	*status = GOT_STATUS_NO_CHANGE;
1051 
1052 	if (lstat(abspath, sb) == -1) {
1053 		if (errno == ENOENT) {
1054 			if (got_fileindex_entry_has_file_on_disk(ie))
1055 				*status = GOT_STATUS_MISSING;
1056 			else
1057 				*status = GOT_STATUS_DELETE;
1058 			return NULL;
1059 		}
1060 		return got_error_from_errno2("lstat", abspath);
1061 	}
1062 
1063 	if (!S_ISREG(sb->st_mode)) {
1064 		*status = GOT_STATUS_OBSTRUCTED;
1065 		return NULL;
1066 	}
1067 
1068 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1069 		*status = GOT_STATUS_DELETE;
1070 		return NULL;
1071 	} else if (!got_fileindex_entry_has_blob(ie)) {
1072 		*status = GOT_STATUS_ADD;
1073 		return NULL;
1074 	}
1075 
1076 	if (!stat_info_differs(ie, sb))
1077 		return NULL;
1078 
1079 	memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1080 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1081 	if (err)
1082 		return err;
1083 
1084 	f = fopen(abspath, "r");
1085 	if (f == NULL) {
1086 		err = got_error_from_errno2("fopen", abspath);
1087 		goto done;
1088 	}
1089 	hdrlen = got_object_blob_get_hdrlen(blob);
1090 	for (;;) {
1091 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1092 		err = got_object_blob_read_block(&blen, blob);
1093 		if (err)
1094 			goto done;
1095 		/* Skip length of blob object header first time around. */
1096 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1097 		if (flen == 0 && ferror(f)) {
1098 			err = got_error_from_errno("fread");
1099 			goto done;
1100 		}
1101 		if (blen == 0) {
1102 			if (flen != 0)
1103 				*status = GOT_STATUS_MODIFY;
1104 			break;
1105 		} else if (flen == 0) {
1106 			if (blen != 0)
1107 				*status = GOT_STATUS_MODIFY;
1108 			break;
1109 		} else if (blen - hdrlen == flen) {
1110 			/* Skip blob object header first time around. */
1111 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1112 				*status = GOT_STATUS_MODIFY;
1113 				break;
1114 			}
1115 		} else {
1116 			*status = GOT_STATUS_MODIFY;
1117 			break;
1118 		}
1119 		hdrlen = 0;
1120 	}
1121 
1122 	if (*status == GOT_STATUS_MODIFY) {
1123 		rewind(f);
1124 		err = get_modified_file_content_status(status, f);
1125 	}
1126 done:
1127 	if (blob)
1128 		got_object_blob_close(blob);
1129 	if (f)
1130 		fclose(f);
1131 	return err;
1132 }
1133 
1134 /*
1135  * Update timestamps in the file index if a file is unmodified and
1136  * we had to run a full content comparison to find out.
1137  */
1138 static const struct got_error *
1139 sync_timestamps(char *ondisk_path, unsigned char status,
1140     struct got_fileindex_entry *ie, struct stat *sb)
1141 {
1142 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1143 		return got_fileindex_entry_update(ie, ondisk_path,
1144 		    ie->blob_sha1, ie->commit_sha1, 1);
1145 
1146 	return NULL;
1147 }
1148 
1149 static const struct got_error *
1150 update_blob(struct got_worktree *worktree,
1151     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1152     struct got_tree_entry *te, const char *path,
1153     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1154     void *progress_arg)
1155 {
1156 	const struct got_error *err = NULL;
1157 	struct got_blob_object *blob = NULL;
1158 	char *ondisk_path;
1159 	unsigned char status = GOT_STATUS_NO_CHANGE;
1160 	struct stat sb;
1161 
1162 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1163 		return got_error_from_errno("asprintf");
1164 
1165 	if (ie) {
1166 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1167 		if (err)
1168 			goto done;
1169 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1170 			sb.st_mode = got_fileindex_perms_to_st(ie);
1171 	} else
1172 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
1173 
1174 	if (status == GOT_STATUS_OBSTRUCTED) {
1175 		err = (*progress_cb)(progress_arg, status, path);
1176 		goto done;
1177 	}
1178 
1179 	if (ie && status != GOT_STATUS_MISSING) {
1180 		if (got_fileindex_entry_has_commit(ie) &&
1181 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1182 		    SHA1_DIGEST_LENGTH) == 0) {
1183 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1184 			if (err)
1185 				goto done;
1186 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1187 			    path);
1188 			goto done;
1189 		}
1190 		if (got_fileindex_entry_has_blob(ie) &&
1191 		    memcmp(ie->blob_sha1, te->id->sha1,
1192 		    SHA1_DIGEST_LENGTH) == 0) {
1193 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1194 			goto done;
1195 		}
1196 	}
1197 
1198 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1199 	if (err)
1200 		goto done;
1201 
1202 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1203 		int update_timestamps;
1204 		struct got_blob_object *blob2 = NULL;
1205 		if (got_fileindex_entry_has_blob(ie)) {
1206 			struct got_object_id id2;
1207 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1208 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
1209 			if (err)
1210 				goto done;
1211 		}
1212 		err = merge_blob(&update_timestamps, worktree, blob2,
1213 		    ondisk_path, path, sb.st_mode, blob,
1214 		    worktree->base_commit_id, repo,
1215 		    progress_cb, progress_arg);
1216 		if (blob2)
1217 			got_object_blob_close(blob2);
1218 		/*
1219 		 * Do not update timestamps of files with local changes.
1220 		 * Otherwise, a future status walk would treat them as
1221 		 * unmodified files again.
1222 		 */
1223 		err = got_fileindex_entry_update(ie, ondisk_path,
1224 		    blob->id.sha1, worktree->base_commit_id->sha1,
1225 		    update_timestamps);
1226 	} else if (status == GOT_STATUS_DELETE) {
1227 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1228 		if (err)
1229 			goto done;
1230 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1231 		    ondisk_path, path, blob, 0);
1232 		if (err)
1233 			goto done;
1234 	} else {
1235 		err = install_blob(worktree, ondisk_path, path, te->mode,
1236 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1237 		    repo, progress_cb, progress_arg);
1238 		if (err)
1239 			goto done;
1240 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1241 		    ondisk_path, path, blob, 1);
1242 		if (err)
1243 			goto done;
1244 	}
1245 	got_object_blob_close(blob);
1246 done:
1247 	free(ondisk_path);
1248 	return err;
1249 }
1250 
1251 static const struct got_error *
1252 remove_ondisk_file(const char *root_path, const char *path)
1253 {
1254 	const struct got_error *err = NULL;
1255 	char *ondisk_path = NULL;
1256 
1257 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1258 		return got_error_from_errno("asprintf");
1259 
1260 	if (unlink(ondisk_path) == -1) {
1261 		if (errno != ENOENT)
1262 			err = got_error_from_errno2("unlink", ondisk_path);
1263 	} else {
1264 		char *parent = dirname(ondisk_path);
1265 		while (parent && strcmp(parent, root_path) != 0) {
1266 			if (rmdir(parent) == -1) {
1267 				if (errno != ENOTEMPTY)
1268 					err = got_error_from_errno2("rmdir",
1269 					    parent);
1270 				break;
1271 			}
1272 			parent = dirname(parent);
1273 		}
1274 	}
1275 	free(ondisk_path);
1276 	return err;
1277 }
1278 
1279 static const struct got_error *
1280 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1281     struct got_fileindex_entry *ie, struct got_repository *repo,
1282     got_worktree_checkout_cb progress_cb, void *progress_arg)
1283 {
1284 	const struct got_error *err = NULL;
1285 	unsigned char status;
1286 	struct stat sb;
1287 	char *ondisk_path;
1288 
1289 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1290 	    == -1)
1291 		return got_error_from_errno("asprintf");
1292 
1293 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1294 	if (err)
1295 		return err;
1296 
1297 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1298 	    status == GOT_STATUS_ADD) {
1299 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1300 		if (err)
1301 			return err;
1302 		/*
1303 		 * Preserve the working file and change the deleted blob's
1304 		 * entry into a schedule-add entry.
1305 		 */
1306 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1307 		    0);
1308 		if (err)
1309 			return err;
1310 	} else {
1311 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1312 		if (err)
1313 			return err;
1314 		if (status == GOT_STATUS_NO_CHANGE) {
1315 			err = remove_ondisk_file(worktree->root_path, ie->path);
1316 			if (err)
1317 				return err;
1318 		}
1319 		got_fileindex_entry_remove(fileindex, ie);
1320 	}
1321 
1322 	return err;
1323 }
1324 
1325 struct diff_cb_arg {
1326     struct got_fileindex *fileindex;
1327     struct got_worktree *worktree;
1328     struct got_repository *repo;
1329     got_worktree_checkout_cb progress_cb;
1330     void *progress_arg;
1331     got_worktree_cancel_cb cancel_cb;
1332     void *cancel_arg;
1333 };
1334 
1335 static const struct got_error *
1336 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1337     struct got_tree_entry *te, const char *parent_path)
1338 {
1339 	struct diff_cb_arg *a = arg;
1340 
1341 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1342 		return got_error(GOT_ERR_CANCELLED);
1343 
1344 	return update_blob(a->worktree, a->fileindex, ie, te,
1345 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1346 }
1347 
1348 static const struct got_error *
1349 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1350 {
1351 	struct diff_cb_arg *a = arg;
1352 
1353 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1354 		return got_error(GOT_ERR_CANCELLED);
1355 
1356 	return delete_blob(a->worktree, a->fileindex, ie,
1357 	    a->repo, a->progress_cb, a->progress_arg);
1358 }
1359 
1360 static const struct got_error *
1361 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1362 {
1363 	struct diff_cb_arg *a = arg;
1364 	const struct got_error *err;
1365 	char *path;
1366 
1367 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1368 		return got_error(GOT_ERR_CANCELLED);
1369 
1370 	if (asprintf(&path, "%s%s%s", parent_path,
1371 	    parent_path[0] ? "/" : "", te->name)
1372 	    == -1)
1373 		return got_error_from_errno("asprintf");
1374 
1375 	if (S_ISDIR(te->mode))
1376 		err = add_dir_on_disk(a->worktree, path);
1377 	else
1378 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1379 		    a->repo, a->progress_cb, a->progress_arg);
1380 
1381 	free(path);
1382 	return err;
1383 }
1384 
1385 static const struct got_error *
1386 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
1387 {
1388 	const struct got_error *err = NULL;
1389 	char *uuidstr = NULL;
1390 	uint32_t uuid_status;
1391 
1392 	*refname = NULL;
1393 
1394 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1395 	if (uuid_status != uuid_s_ok)
1396 		return got_error_uuid(uuid_status);
1397 
1398 	if (asprintf(refname, "%s-%s", prefix, uuidstr)
1399 	    == -1) {
1400 		err = got_error_from_errno("asprintf");
1401 		*refname = NULL;
1402 	}
1403 	free(uuidstr);
1404 	return err;
1405 }
1406 
1407 const struct got_error *
1408 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1409 {
1410 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
1411 }
1412 
1413 static const struct got_error *
1414 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
1415 {
1416 	return get_ref_name(refname, worktree,
1417 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
1418 }
1419 
1420 static const struct got_error *
1421 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
1422 {
1423 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
1424 }
1425 
1426 static const struct got_error *
1427 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
1428 {
1429 	return get_ref_name(refname, worktree,
1430 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
1431 }
1432 
1433 static const struct got_error *
1434 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
1435 {
1436 	return get_ref_name(refname, worktree,
1437 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
1438 }
1439 
1440 static const struct got_error *
1441 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
1442 {
1443 	return get_ref_name(refname, worktree,
1444 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
1445 }
1446 
1447 static const struct got_error *
1448 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
1449 {
1450 	return get_ref_name(refname, worktree,
1451 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
1452 }
1453 
1454 static const struct got_error *
1455 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
1456 {
1457 	return get_ref_name(refname, worktree,
1458 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
1459 }
1460 
1461 static const struct got_error *
1462 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
1463 {
1464 	return get_ref_name(refname, worktree,
1465 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
1466 }
1467 
1468 const struct got_error *
1469 got_worktree_get_histedit_script_path(char **path,
1470     struct got_worktree *worktree)
1471 {
1472 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
1473 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
1474 		*path = NULL;
1475 		return got_error_from_errno("asprintf");
1476 	}
1477 	return NULL;
1478 }
1479 
1480 /*
1481  * Prevent Git's garbage collector from deleting our base commit by
1482  * setting a reference to our base commit's ID.
1483  */
1484 static const struct got_error *
1485 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1486 {
1487 	const struct got_error *err = NULL;
1488 	struct got_reference *ref = NULL;
1489 	char *refname;
1490 
1491 	err = got_worktree_get_base_ref_name(&refname, worktree);
1492 	if (err)
1493 		return err;
1494 
1495 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1496 	if (err)
1497 		goto done;
1498 
1499 	err = got_ref_write(ref, repo);
1500 done:
1501 	free(refname);
1502 	if (ref)
1503 		got_ref_close(ref);
1504 	return err;
1505 }
1506 
1507 static const struct got_error *
1508 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
1509 {
1510 	const struct got_error *err = NULL;
1511 
1512 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1513 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1514 		err = got_error_from_errno("asprintf");
1515 		*fileindex_path = NULL;
1516 	}
1517 	return err;
1518 }
1519 
1520 
1521 static const struct got_error *
1522 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1523    struct got_worktree *worktree)
1524 {
1525 	const struct got_error *err = NULL;
1526 	FILE *index = NULL;
1527 
1528 	*fileindex_path = NULL;
1529 	*fileindex = got_fileindex_alloc();
1530 	if (*fileindex == NULL)
1531 		return got_error_from_errno("got_fileindex_alloc");
1532 
1533 	err = get_fileindex_path(fileindex_path, worktree);
1534 	if (err)
1535 		goto done;
1536 
1537 	index = fopen(*fileindex_path, "rb");
1538 	if (index == NULL) {
1539 		if (errno != ENOENT)
1540 			err = got_error_from_errno2("fopen", *fileindex_path);
1541 	} else {
1542 		err = got_fileindex_read(*fileindex, index);
1543 		if (fclose(index) != 0 && err == NULL)
1544 			err = got_error_from_errno("fclose");
1545 	}
1546 done:
1547 	if (err) {
1548 		free(*fileindex_path);
1549 		*fileindex_path = NULL;
1550 		got_fileindex_free(*fileindex);
1551 		*fileindex = NULL;
1552 	}
1553 	return err;
1554 }
1555 
1556 struct bump_base_commit_id_arg {
1557 	struct got_object_id *base_commit_id;
1558 	const char *path;
1559 	size_t path_len;
1560 	const char *entry_name;
1561 	got_worktree_checkout_cb progress_cb;
1562 	void *progress_arg;
1563 };
1564 
1565 /* Bump base commit ID of all files within an updated part of the work tree. */
1566 static const struct got_error *
1567 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
1568 {
1569 	const struct got_error *err;
1570 	struct bump_base_commit_id_arg *a = arg;
1571 
1572 	if (a->entry_name) {
1573 		if (strcmp(ie->path, a->path) != 0)
1574 			return NULL;
1575 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
1576 		return NULL;
1577 
1578 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
1579 	    SHA1_DIGEST_LENGTH) == 0)
1580 		return NULL;
1581 
1582 	if (a->progress_cb) {
1583 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
1584 		    ie->path);
1585 		if (err)
1586 			return err;
1587 	}
1588 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
1589 	return NULL;
1590 }
1591 
1592 static const struct got_error *
1593 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
1594 {
1595 	const struct got_error *err = NULL;
1596 	char *new_fileindex_path = NULL;
1597 	FILE *new_index = NULL;
1598 
1599 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1600 	    fileindex_path);
1601 	if (err)
1602 		goto done;
1603 
1604 	err = got_fileindex_write(fileindex, new_index);
1605 	if (err)
1606 		goto done;
1607 
1608 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1609 		err = got_error_from_errno3("rename", new_fileindex_path,
1610 		    fileindex_path);
1611 		unlink(new_fileindex_path);
1612 	}
1613 done:
1614 	if (new_index)
1615 		fclose(new_index);
1616 	free(new_fileindex_path);
1617 	return err;
1618 }
1619 
1620 static const struct got_error *
1621 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
1622     struct got_object_id **tree_id, const char *wt_relpath,
1623     struct got_worktree *worktree, struct got_repository *repo)
1624 {
1625 	const struct got_error *err = NULL;
1626 	struct got_object_id *id = NULL;
1627 	char *in_repo_path = NULL;
1628 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
1629 
1630 	*entry_type = GOT_OBJ_TYPE_ANY;
1631 	*tree_relpath = NULL;
1632 	*tree_id = NULL;
1633 
1634 	if (wt_relpath[0] == '\0') {
1635 		/* Check out all files within the work tree. */
1636 		*entry_type = GOT_OBJ_TYPE_TREE;
1637 		*tree_relpath = strdup("");
1638 		if (*tree_relpath == NULL) {
1639 			err = got_error_from_errno("strdup");
1640 			goto done;
1641 		}
1642 		err = got_object_id_by_path(tree_id, repo,
1643 		    worktree->base_commit_id, worktree->path_prefix);
1644 		if (err)
1645 			goto done;
1646 		return NULL;
1647 	}
1648 
1649 	/* Check out a subset of files in the work tree. */
1650 
1651 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
1652 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
1653 		err = got_error_from_errno("asprintf");
1654 		goto done;
1655 	}
1656 
1657 	err = got_object_id_by_path(&id, repo, worktree->base_commit_id,
1658 	    in_repo_path);
1659 	if (err)
1660 		goto done;
1661 
1662 	free(in_repo_path);
1663 	in_repo_path = NULL;
1664 
1665 	err = got_object_get_type(entry_type, repo, id);
1666 	if (err)
1667 		goto done;
1668 
1669 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
1670 		/* Check out a single file. */
1671 		if (strchr(wt_relpath, '/')  == NULL) {
1672 			/* Check out a single file in work tree's root dir. */
1673 			in_repo_path = strdup(worktree->path_prefix);
1674 			if (in_repo_path == NULL) {
1675 				err = got_error_from_errno("strdup");
1676 				goto done;
1677 			}
1678 			*tree_relpath = strdup("");
1679 			if (*tree_relpath == NULL) {
1680 				err = got_error_from_errno("strdup");
1681 				goto done;
1682 			}
1683 		} else {
1684 			/* Check out a single file in a subdirectory. */
1685 			err = got_path_dirname(tree_relpath, wt_relpath);
1686 			if (err)
1687 				return err;
1688 			if (asprintf(&in_repo_path, "%s%s%s",
1689 			    worktree->path_prefix, is_root_wt ? "" : "/",
1690 			    *tree_relpath) == -1) {
1691 				err = got_error_from_errno("asprintf");
1692 				goto done;
1693 			}
1694 		}
1695 		err = got_object_id_by_path(tree_id, repo,
1696 		    worktree->base_commit_id, in_repo_path);
1697 	} else {
1698 		/* Check out all files within a subdirectory. */
1699 		*tree_id = got_object_id_dup(id);
1700 		if (*tree_id == NULL) {
1701 			err = got_error_from_errno("got_object_id_dup");
1702 			goto done;
1703 		}
1704 		*tree_relpath = strdup(wt_relpath);
1705 		if (*tree_relpath == NULL) {
1706 			err = got_error_from_errno("strdup");
1707 			goto done;
1708 		}
1709 	}
1710 done:
1711 	free(id);
1712 	free(in_repo_path);
1713 	if (err) {
1714 		*entry_type = GOT_OBJ_TYPE_ANY;
1715 		free(*tree_relpath);
1716 		*tree_relpath = NULL;
1717 		free(*tree_id);
1718 		*tree_id = NULL;
1719 	}
1720 	return err;
1721 }
1722 
1723 static const struct got_error *
1724 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
1725     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
1726     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1727     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1728 {
1729 	const struct got_error *err = NULL;
1730 	struct got_commit_object *commit = NULL;
1731 	struct got_tree_object *tree = NULL;
1732 	struct got_fileindex_diff_tree_cb diff_cb;
1733 	struct diff_cb_arg arg;
1734 
1735 	err = ref_base_commit(worktree, repo);
1736 	if (err)
1737 		goto done;
1738 
1739 	err = got_object_open_as_commit(&commit, repo,
1740 	   worktree->base_commit_id);
1741 	if (err)
1742 		goto done;
1743 
1744 	err = got_object_open_as_tree(&tree, repo, tree_id);
1745 	if (err)
1746 		goto done;
1747 
1748 	if (entry_name &&
1749 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1750 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1751 		goto done;
1752 	}
1753 
1754 	diff_cb.diff_old_new = diff_old_new;
1755 	diff_cb.diff_old = diff_old;
1756 	diff_cb.diff_new = diff_new;
1757 	arg.fileindex = fileindex;
1758 	arg.worktree = worktree;
1759 	arg.repo = repo;
1760 	arg.progress_cb = progress_cb;
1761 	arg.progress_arg = progress_arg;
1762 	arg.cancel_cb = cancel_cb;
1763 	arg.cancel_arg = cancel_arg;
1764 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
1765 	    entry_name, repo, &diff_cb, &arg);
1766 done:
1767 	if (tree)
1768 		got_object_tree_close(tree);
1769 	if (commit)
1770 		got_object_commit_close(commit);
1771 	return err;
1772 }
1773 
1774 const struct got_error *
1775 got_worktree_checkout_files(struct got_worktree *worktree,
1776     struct got_pathlist_head *paths, struct got_repository *repo,
1777     got_worktree_checkout_cb progress_cb, void *progress_arg,
1778     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1779 {
1780 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1781 	struct got_commit_object *commit = NULL;
1782 	struct got_tree_object *tree = NULL;
1783 	struct got_fileindex *fileindex = NULL;
1784 	char *fileindex_path = NULL;
1785 	struct got_pathlist_entry *pe;
1786 	struct tree_path_data {
1787 		SIMPLEQ_ENTRY(tree_path_data) entry;
1788 		struct got_object_id *tree_id;
1789 		int entry_type;
1790 		char *relpath;
1791 		char *entry_name;
1792 	} *tpd = NULL;
1793 	SIMPLEQ_HEAD(tree_paths, tree_path_data) tree_paths;
1794 
1795 	SIMPLEQ_INIT(&tree_paths);
1796 
1797 	err = lock_worktree(worktree, LOCK_EX);
1798 	if (err)
1799 		return err;
1800 
1801 	/* Map all specified paths to in-repository trees. */
1802 	TAILQ_FOREACH(pe, paths, entry) {
1803 		tpd = malloc(sizeof(*tpd));
1804 		if (tpd == NULL) {
1805 			err = got_error_from_errno("malloc");
1806 			goto done;
1807 		}
1808 
1809 		err = find_tree_entry_for_checkout(&tpd->entry_type,
1810 		    &tpd->relpath, &tpd->tree_id, pe->path, worktree, repo);
1811 		if (err) {
1812 			free(tpd);
1813 			goto done;
1814 		}
1815 
1816 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
1817 			err = got_path_basename(&tpd->entry_name, pe->path);
1818 			if (err) {
1819 				free(tpd->relpath);
1820 				free(tpd->tree_id);
1821 				free(tpd);
1822 				goto done;
1823 			}
1824 		} else
1825 			tpd->entry_name = NULL;
1826 
1827 		SIMPLEQ_INSERT_TAIL(&tree_paths, tpd, entry);
1828 	}
1829 
1830 	/*
1831 	 * Read the file index.
1832 	 * Checking out files is supposed to be an idempotent operation.
1833 	 * If the on-disk file index is incomplete we will try to complete it.
1834 	 */
1835 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1836 	if (err)
1837 		goto done;
1838 
1839 	tpd = SIMPLEQ_FIRST(&tree_paths);
1840 	TAILQ_FOREACH(pe, paths, entry) {
1841 		struct bump_base_commit_id_arg bbc_arg;
1842 
1843 		err = checkout_files(worktree, fileindex, tpd->relpath,
1844 		    tpd->tree_id, tpd->entry_name, repo,
1845 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
1846 		if (err)
1847 			break;
1848 
1849 		bbc_arg.base_commit_id = worktree->base_commit_id;
1850 		bbc_arg.entry_name = tpd->entry_name;
1851 		bbc_arg.path = pe->path;
1852 		bbc_arg.path_len = pe->path_len;
1853 		bbc_arg.progress_cb = progress_cb;
1854 		bbc_arg.progress_arg = progress_arg;
1855 		err = got_fileindex_for_each_entry_safe(fileindex,
1856 		    bump_base_commit_id, &bbc_arg);
1857 		if (err)
1858 			break;
1859 
1860 		tpd = SIMPLEQ_NEXT(tpd, entry);
1861 	}
1862 	sync_err = sync_fileindex(fileindex, fileindex_path);
1863 	if (sync_err && err == NULL)
1864 		err = sync_err;
1865 done:
1866 	free(fileindex_path);
1867 	if (tree)
1868 		got_object_tree_close(tree);
1869 	if (commit)
1870 		got_object_commit_close(commit);
1871 	if (fileindex)
1872 		got_fileindex_free(fileindex);
1873 	while (!SIMPLEQ_EMPTY(&tree_paths)) {
1874 		tpd = SIMPLEQ_FIRST(&tree_paths);
1875 		SIMPLEQ_REMOVE_HEAD(&tree_paths, entry);
1876 		free(tpd->relpath);
1877 		free(tpd->tree_id);
1878 		free(tpd);
1879 	}
1880 	unlockerr = lock_worktree(worktree, LOCK_SH);
1881 	if (unlockerr && err == NULL)
1882 		err = unlockerr;
1883 	return err;
1884 }
1885 
1886 struct merge_file_cb_arg {
1887     struct got_worktree *worktree;
1888     struct got_fileindex *fileindex;
1889     got_worktree_checkout_cb progress_cb;
1890     void *progress_arg;
1891     got_worktree_cancel_cb cancel_cb;
1892     void *cancel_arg;
1893     struct got_object_id *commit_id2;
1894 };
1895 
1896 static const struct got_error *
1897 merge_file_cb(void *arg, struct got_blob_object *blob1,
1898     struct got_blob_object *blob2, struct got_object_id *id1,
1899     struct got_object_id *id2, const char *path1, const char *path2,
1900     struct got_repository *repo)
1901 {
1902 	static const struct got_error *err = NULL;
1903 	struct merge_file_cb_arg *a = arg;
1904 	struct got_fileindex_entry *ie;
1905 	char *ondisk_path = NULL;
1906 	struct stat sb;
1907 	unsigned char status;
1908 	int local_changes_subsumed;
1909 
1910 	if (blob1 && blob2) {
1911 		ie = got_fileindex_entry_get(a->fileindex, path2,
1912 		    strlen(path2));
1913 		if (ie == NULL)
1914 			return (*a->progress_cb)(a->progress_arg,
1915 			    GOT_STATUS_MISSING, path2);
1916 
1917 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1918 		    path2) == -1)
1919 			return got_error_from_errno("asprintf");
1920 
1921 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1922 		if (err)
1923 			goto done;
1924 
1925 		if (status == GOT_STATUS_DELETE) {
1926 			err = (*a->progress_cb)(a->progress_arg,
1927 			    GOT_STATUS_MERGE, path2);
1928 			goto done;
1929 		}
1930 		if (status != GOT_STATUS_NO_CHANGE &&
1931 		    status != GOT_STATUS_MODIFY &&
1932 		    status != GOT_STATUS_CONFLICT &&
1933 		    status != GOT_STATUS_ADD) {
1934 			err = (*a->progress_cb)(a->progress_arg, status, path2);
1935 			goto done;
1936 		}
1937 
1938 		err = merge_blob(&local_changes_subsumed, a->worktree, blob1,
1939 		    ondisk_path, path2, sb.st_mode, blob2, a->commit_id2, repo,
1940 		    a->progress_cb, a->progress_arg);
1941 	} else if (blob1) {
1942 		ie = got_fileindex_entry_get(a->fileindex, path1,
1943 		    strlen(path1));
1944 		if (ie == NULL)
1945 			return (*a->progress_cb)(a->progress_arg,
1946 			    GOT_STATUS_MISSING, path2);
1947 
1948 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1949 		    path1) == -1)
1950 			return got_error_from_errno("asprintf");
1951 
1952 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1953 		if (err)
1954 			goto done;
1955 
1956 		switch (status) {
1957 		case GOT_STATUS_NO_CHANGE:
1958 			err = (*a->progress_cb)(a->progress_arg,
1959 			    GOT_STATUS_DELETE, path1);
1960 			if (err)
1961 				goto done;
1962 			err = remove_ondisk_file(a->worktree->root_path, path1);
1963 			if (err)
1964 				goto done;
1965 			if (ie)
1966 				got_fileindex_entry_mark_deleted_from_disk(ie);
1967 			break;
1968 		case GOT_STATUS_DELETE:
1969 		case GOT_STATUS_MISSING:
1970 			err = (*a->progress_cb)(a->progress_arg,
1971 			    GOT_STATUS_DELETE, path1);
1972 			if (err)
1973 				goto done;
1974 			if (ie)
1975 				got_fileindex_entry_mark_deleted_from_disk(ie);
1976 			break;
1977 		case GOT_STATUS_ADD:
1978 		case GOT_STATUS_MODIFY:
1979 		case GOT_STATUS_CONFLICT:
1980 			err = (*a->progress_cb)(a->progress_arg,
1981 			    GOT_STATUS_CANNOT_DELETE, path1);
1982 			if (err)
1983 				goto done;
1984 			break;
1985 		case GOT_STATUS_OBSTRUCTED:
1986 			err = (*a->progress_cb)(a->progress_arg, status, path1);
1987 			if (err)
1988 				goto done;
1989 			break;
1990 		default:
1991 			break;
1992 		}
1993 	} else if (blob2) {
1994 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1995 		    path2) == -1)
1996 			return got_error_from_errno("asprintf");
1997 		ie = got_fileindex_entry_get(a->fileindex, path2,
1998 		    strlen(path2));
1999 		if (ie) {
2000 			err = get_file_status(&status, &sb, ie, ondisk_path,
2001 			    repo);
2002 			if (err)
2003 				goto done;
2004 			if (status != GOT_STATUS_NO_CHANGE &&
2005 			    status != GOT_STATUS_MODIFY &&
2006 			    status != GOT_STATUS_CONFLICT &&
2007 			    status != GOT_STATUS_ADD) {
2008 				err = (*a->progress_cb)(a->progress_arg,
2009 				    status, path2);
2010 				goto done;
2011 			}
2012 			err = merge_blob(&local_changes_subsumed, a->worktree,
2013 			    NULL, ondisk_path, path2, sb.st_mode, blob2,
2014 			    a->commit_id2, repo,
2015 			    a->progress_cb, a->progress_arg);
2016 			if (status == GOT_STATUS_DELETE) {
2017 				err = update_blob_fileindex_entry(a->worktree,
2018 				    a->fileindex, ie, ondisk_path, ie->path,
2019 				    blob2, 0);
2020 				if (err)
2021 					goto done;
2022 			}
2023 		} else {
2024 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
2025 			err = install_blob(a->worktree, ondisk_path, path2,
2026 			    /* XXX get this from parent tree! */
2027 			    GOT_DEFAULT_FILE_MODE,
2028 			    sb.st_mode, blob2, 0, 0, repo,
2029 			    a->progress_cb, a->progress_arg);
2030 			if (err)
2031 				goto done;
2032 			err = got_fileindex_entry_alloc(&ie,
2033 			    ondisk_path, path2, NULL, NULL);
2034 			if (err)
2035 				goto done;
2036 			err = got_fileindex_entry_add(a->fileindex, ie);
2037 			if (err) {
2038 				got_fileindex_entry_free(ie);
2039 				goto done;
2040 			}
2041 		}
2042 	}
2043 done:
2044 	free(ondisk_path);
2045 	return err;
2046 }
2047 
2048 struct check_merge_ok_arg {
2049 	struct got_worktree *worktree;
2050 	struct got_repository *repo;
2051 };
2052 
2053 static const struct got_error *
2054 check_merge_ok(void *arg, struct got_fileindex_entry *ie)
2055 {
2056 	const struct got_error *err = NULL;
2057 	struct check_merge_ok_arg *a = arg;
2058 	unsigned char status;
2059 	struct stat sb;
2060 	char *ondisk_path;
2061 
2062 	/* Reject merges into a work tree with mixed base commits. */
2063 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
2064 	    SHA1_DIGEST_LENGTH))
2065 		return got_error(GOT_ERR_MIXED_COMMITS);
2066 
2067 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
2068 	    == -1)
2069 		return got_error_from_errno("asprintf");
2070 
2071 	/* Reject merges into a work tree with conflicted files. */
2072 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
2073 	if (err)
2074 		return err;
2075 	if (status == GOT_STATUS_CONFLICT)
2076 		return got_error(GOT_ERR_CONFLICTS);
2077 
2078 	return NULL;
2079 }
2080 
2081 static const struct got_error *
2082 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2083     const char *fileindex_path, struct got_object_id *commit_id1,
2084     struct got_object_id *commit_id2, struct got_repository *repo,
2085     got_worktree_checkout_cb progress_cb, void *progress_arg,
2086     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2087 {
2088 	const struct got_error *err = NULL, *sync_err;
2089 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
2090 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
2091 	struct merge_file_cb_arg arg;
2092 
2093 	if (commit_id1) {
2094 		err = got_object_id_by_path(&tree_id1, repo, commit_id1,
2095 		    worktree->path_prefix);
2096 		if (err)
2097 			goto done;
2098 
2099 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
2100 		if (err)
2101 			goto done;
2102 	}
2103 
2104 	err = got_object_id_by_path(&tree_id2, repo, commit_id2,
2105 	    worktree->path_prefix);
2106 	if (err)
2107 		goto done;
2108 
2109 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
2110 	if (err)
2111 		goto done;
2112 
2113 	arg.worktree = worktree;
2114 	arg.fileindex = fileindex;
2115 	arg.progress_cb = progress_cb;
2116 	arg.progress_arg = progress_arg;
2117 	arg.cancel_cb = cancel_cb;
2118 	arg.cancel_arg = cancel_arg;
2119 	arg.commit_id2 = commit_id2;
2120 	err = got_diff_tree(tree1, tree2, "", "", repo, merge_file_cb, &arg, 1);
2121 	sync_err = sync_fileindex(fileindex, fileindex_path);
2122 	if (sync_err && err == NULL)
2123 		err = sync_err;
2124 done:
2125 	if (tree1)
2126 		got_object_tree_close(tree1);
2127 	if (tree2)
2128 		got_object_tree_close(tree2);
2129 	return err;
2130 }
2131 
2132 const struct got_error *
2133 got_worktree_merge_files(struct got_worktree *worktree,
2134     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
2135     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2136     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2137 {
2138 	const struct got_error *err, *unlockerr;
2139 	char *fileindex_path = NULL;
2140 	struct got_fileindex *fileindex = NULL;
2141 	struct check_merge_ok_arg mok_arg;
2142 
2143 	err = lock_worktree(worktree, LOCK_EX);
2144 	if (err)
2145 		return err;
2146 
2147 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2148 	if (err)
2149 		goto done;
2150 
2151 	mok_arg.worktree = worktree;
2152 	mok_arg.repo = repo;
2153 	err = got_fileindex_for_each_entry_safe(fileindex, check_merge_ok,
2154 	    &mok_arg);
2155 	if (err)
2156 		goto done;
2157 
2158 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
2159 	    commit_id2, repo, progress_cb, progress_arg, cancel_cb, cancel_arg);
2160 done:
2161 	if (fileindex)
2162 		got_fileindex_free(fileindex);
2163 	free(fileindex_path);
2164 	unlockerr = lock_worktree(worktree, LOCK_SH);
2165 	if (unlockerr && err == NULL)
2166 		err = unlockerr;
2167 	return err;
2168 }
2169 
2170 struct diff_dir_cb_arg {
2171     struct got_fileindex *fileindex;
2172     struct got_worktree *worktree;
2173     const char *status_path;
2174     size_t status_path_len;
2175     struct got_repository *repo;
2176     got_worktree_status_cb status_cb;
2177     void *status_arg;
2178     got_worktree_cancel_cb cancel_cb;
2179     void *cancel_arg;
2180 };
2181 
2182 static const struct got_error *
2183 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
2184     got_worktree_status_cb status_cb, void *status_arg,
2185     struct got_repository *repo)
2186 {
2187 	const struct got_error *err = NULL;
2188 	unsigned char status = GOT_STATUS_NO_CHANGE;
2189 	struct stat sb;
2190 	struct got_object_id blob_id, commit_id;
2191 
2192 	err = get_file_status(&status, &sb, ie, abspath, repo);
2193 	if (err == NULL && status != GOT_STATUS_NO_CHANGE) {
2194 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2195 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2196 		err = (*status_cb)(status_arg, status, ie->path, &blob_id,
2197 		    &commit_id);
2198 	}
2199 	return err;
2200 }
2201 
2202 static const struct got_error *
2203 status_old_new(void *arg, struct got_fileindex_entry *ie,
2204     struct dirent *de, const char *parent_path)
2205 {
2206 	const struct got_error *err = NULL;
2207 	struct diff_dir_cb_arg *a = arg;
2208 	char *abspath;
2209 
2210 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2211 		return got_error(GOT_ERR_CANCELLED);
2212 
2213 	if (got_path_cmp(parent_path, a->status_path,
2214 	    strlen(parent_path), a->status_path_len) != 0 &&
2215 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
2216 		return NULL;
2217 
2218 	if (parent_path[0]) {
2219 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
2220 		    parent_path, de->d_name) == -1)
2221 			return got_error_from_errno("asprintf");
2222 	} else {
2223 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
2224 		    de->d_name) == -1)
2225 			return got_error_from_errno("asprintf");
2226 	}
2227 
2228 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
2229 	    a->repo);
2230 	free(abspath);
2231 	return err;
2232 }
2233 
2234 static const struct got_error *
2235 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2236 {
2237 	struct diff_dir_cb_arg *a = arg;
2238 	struct got_object_id blob_id, commit_id;
2239 	unsigned char status;
2240 
2241 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2242 		return got_error(GOT_ERR_CANCELLED);
2243 
2244 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
2245 		return NULL;
2246 
2247 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2248 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2249 	if (got_fileindex_entry_has_file_on_disk(ie))
2250 		status = GOT_STATUS_MISSING;
2251 	else
2252 		status = GOT_STATUS_DELETE;
2253 	return (*a->status_cb)(a->status_arg, status, ie->path, &blob_id,
2254 	    &commit_id);
2255 }
2256 
2257 static const struct got_error *
2258 status_new(void *arg, struct dirent *de, const char *parent_path)
2259 {
2260 	const struct got_error *err = NULL;
2261 	struct diff_dir_cb_arg *a = arg;
2262 	char *path = NULL;
2263 
2264 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2265 		return got_error(GOT_ERR_CANCELLED);
2266 
2267 	if (de->d_type == DT_DIR)
2268 		return NULL;
2269 
2270 	/* XXX ignore symlinks for now */
2271 	if (de->d_type == DT_LNK)
2272 		return NULL;
2273 
2274 	if (parent_path[0]) {
2275 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
2276 			return got_error_from_errno("asprintf");
2277 	} else {
2278 		path = de->d_name;
2279 	}
2280 
2281 	if (got_path_is_child(path, a->status_path, a->status_path_len))
2282 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
2283 		    path, NULL, NULL);
2284 	if (parent_path[0])
2285 		free(path);
2286 	return err;
2287 }
2288 
2289 static const struct got_error *
2290 report_single_file_status(const char *path, const char *ondisk_path,
2291 struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
2292 void *status_arg, struct got_repository *repo)
2293 {
2294 	struct got_fileindex_entry *ie;
2295 	struct stat sb;
2296 
2297 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
2298 	if (ie)
2299 		return report_file_status(ie, ondisk_path, status_cb,
2300 		    status_arg, repo);
2301 
2302 	if (lstat(ondisk_path, &sb) == -1) {
2303 		if (errno != ENOENT)
2304 			return got_error_from_errno2("lstat", ondisk_path);
2305 		return NULL;
2306 	}
2307 
2308 	if (S_ISREG(sb.st_mode))
2309 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED, path,
2310 		    NULL, NULL);
2311 
2312 	return NULL;
2313 }
2314 
2315 static const struct got_error *
2316 worktree_status(struct got_worktree *worktree, const char *path,
2317     struct got_fileindex *fileindex, struct got_repository *repo,
2318     got_worktree_status_cb status_cb, void *status_arg,
2319     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2320 {
2321 	const struct got_error *err = NULL;
2322 	DIR *workdir = NULL;
2323 	struct got_fileindex_diff_dir_cb fdiff_cb;
2324 	struct diff_dir_cb_arg arg;
2325 	char *ondisk_path = NULL;
2326 
2327 	if (asprintf(&ondisk_path, "%s%s%s",
2328 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
2329 		return got_error_from_errno("asprintf");
2330 
2331 	workdir = opendir(ondisk_path);
2332 	if (workdir == NULL) {
2333 		if (errno != ENOTDIR && errno != ENOENT)
2334 			err = got_error_from_errno2("opendir", ondisk_path);
2335 		else
2336 			err = report_single_file_status(path, ondisk_path,
2337 			    fileindex, status_cb, status_arg, repo);
2338 	} else {
2339 		fdiff_cb.diff_old_new = status_old_new;
2340 		fdiff_cb.diff_old = status_old;
2341 		fdiff_cb.diff_new = status_new;
2342 		arg.fileindex = fileindex;
2343 		arg.worktree = worktree;
2344 		arg.status_path = path;
2345 		arg.status_path_len = strlen(path);
2346 		arg.repo = repo;
2347 		arg.status_cb = status_cb;
2348 		arg.status_arg = status_arg;
2349 		arg.cancel_cb = cancel_cb;
2350 		arg.cancel_arg = cancel_arg;
2351 		err = got_fileindex_diff_dir(fileindex, workdir,
2352 		    worktree->root_path, path, repo, &fdiff_cb, &arg);
2353 	}
2354 
2355 	if (workdir)
2356 		closedir(workdir);
2357 	free(ondisk_path);
2358 	return err;
2359 }
2360 
2361 const struct got_error *
2362 got_worktree_status(struct got_worktree *worktree,
2363     struct got_pathlist_head *paths, struct got_repository *repo,
2364     got_worktree_status_cb status_cb, void *status_arg,
2365     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2366 {
2367 	const struct got_error *err = NULL;
2368 	char *fileindex_path = NULL;
2369 	struct got_fileindex *fileindex = NULL;
2370 	struct got_pathlist_entry *pe;
2371 
2372 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2373 	if (err)
2374 		return err;
2375 
2376 	TAILQ_FOREACH(pe, paths, entry) {
2377 		err = worktree_status(worktree, pe->path, fileindex, repo,
2378 			status_cb, status_arg, cancel_cb, cancel_arg);
2379 		if (err)
2380 			break;
2381 	}
2382 	free(fileindex_path);
2383 	got_fileindex_free(fileindex);
2384 	return err;
2385 }
2386 
2387 const struct got_error *
2388 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
2389     const char *arg)
2390 {
2391 	const struct got_error *err = NULL;
2392 	char *resolved, *cwd = NULL, *path = NULL;
2393 	size_t len;
2394 
2395 	*wt_path = NULL;
2396 
2397 	resolved = realpath(arg, NULL);
2398 	if (resolved == NULL) {
2399 		if (errno != ENOENT)
2400 			return got_error_from_errno2("realpath", arg);
2401 		cwd = getcwd(NULL, 0);
2402 		if (cwd == NULL)
2403 			return got_error_from_errno("getcwd");
2404 		if (asprintf(&resolved, "%s/%s", cwd, arg) == -1) {
2405 			err = got_error_from_errno("asprintf");
2406 			goto done;
2407 		}
2408 	}
2409 
2410 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
2411 	    strlen(got_worktree_get_root_path(worktree)))) {
2412 		err = got_error(GOT_ERR_BAD_PATH);
2413 		goto done;
2414 	}
2415 
2416 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
2417 		err = got_path_skip_common_ancestor(&path,
2418 		    got_worktree_get_root_path(worktree), resolved);
2419 		if (err)
2420 			goto done;
2421 	} else {
2422 		path = strdup("");
2423 		if (path == NULL) {
2424 			err = got_error_from_errno("strdup");
2425 			goto done;
2426 		}
2427 	}
2428 
2429 	/* XXX status walk can't deal with trailing slash! */
2430 	len = strlen(path);
2431 	while (len > 0 && path[len - 1] == '/') {
2432 		path[len - 1] = '\0';
2433 		len--;
2434 	}
2435 done:
2436 	free(resolved);
2437 	free(cwd);
2438 	if (err == NULL)
2439 		*wt_path = path;
2440 	else
2441 		free(path);
2442 	return err;
2443 }
2444 
2445 static const struct got_error *
2446 schedule_addition(const char *ondisk_path, struct got_fileindex *fileindex,
2447     const char *relpath, got_worktree_status_cb status_cb, void *status_arg,
2448     struct got_repository *repo)
2449 {
2450 	const struct got_error *err = NULL;
2451 	struct got_fileindex_entry *ie;
2452 
2453 	/* Re-adding an existing entry is a no-op. */
2454 	if (got_fileindex_entry_get(fileindex, relpath, strlen(relpath)))
2455 		return NULL;
2456 
2457 	err = got_fileindex_entry_alloc(&ie, ondisk_path, relpath, NULL, NULL);
2458 	if (err)
2459 		return err;
2460 
2461 	err = got_fileindex_entry_add(fileindex, ie);
2462 	if (err) {
2463 		got_fileindex_entry_free(ie);
2464 		return err;
2465 	}
2466 
2467 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2468 }
2469 
2470 const struct got_error *
2471 got_worktree_schedule_add(struct got_worktree *worktree,
2472     struct got_pathlist_head *ondisk_paths,
2473     got_worktree_status_cb status_cb, void *status_arg,
2474     struct got_repository *repo)
2475 {
2476 	struct got_fileindex *fileindex = NULL;
2477 	char *fileindex_path = NULL;
2478 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2479 	struct got_pathlist_entry *pe;
2480 
2481 	err = lock_worktree(worktree, LOCK_EX);
2482 	if (err)
2483 		return err;
2484 
2485 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2486 	if (err)
2487 		goto done;
2488 
2489 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2490 		char *relpath;
2491 		err = got_path_skip_common_ancestor(&relpath,
2492 		    got_worktree_get_root_path(worktree), pe->path);
2493 		if (err)
2494 			break;
2495 		err = schedule_addition(pe->path, fileindex, relpath,
2496 		    status_cb, status_arg, repo);
2497 		free(relpath);
2498 		if (err)
2499 			break;
2500 	}
2501 	sync_err = sync_fileindex(fileindex, fileindex_path);
2502 	if (sync_err && err == NULL)
2503 		err = sync_err;
2504 done:
2505 	free(fileindex_path);
2506 	if (fileindex)
2507 		got_fileindex_free(fileindex);
2508 	unlockerr = lock_worktree(worktree, LOCK_SH);
2509 	if (unlockerr && err == NULL)
2510 		err = unlockerr;
2511 	return err;
2512 }
2513 
2514 static const struct got_error *
2515 schedule_for_deletion(const char *ondisk_path, struct got_fileindex *fileindex,
2516     const char *relpath, int delete_local_mods,
2517     got_worktree_status_cb status_cb, void *status_arg,
2518     struct got_repository *repo)
2519 {
2520 	const struct got_error *err = NULL;
2521 	struct got_fileindex_entry *ie = NULL;
2522 	unsigned char status;
2523 	struct stat sb;
2524 
2525 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2526 	if (ie == NULL)
2527 		return got_error(GOT_ERR_BAD_PATH);
2528 
2529 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2530 	if (err)
2531 		return err;
2532 
2533 	if (status != GOT_STATUS_NO_CHANGE) {
2534 		if (status == GOT_STATUS_DELETE)
2535 			return NULL;
2536 		if (status != GOT_STATUS_MODIFY)
2537 			return got_error(GOT_ERR_FILE_STATUS);
2538 		if (!delete_local_mods)
2539 			return got_error(GOT_ERR_FILE_MODIFIED);
2540 	}
2541 
2542 	if (unlink(ondisk_path) != 0)
2543 		return got_error_from_errno2("unlink", ondisk_path);
2544 
2545 	got_fileindex_entry_mark_deleted_from_disk(ie);
2546 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2547 }
2548 
2549 const struct got_error *
2550 got_worktree_schedule_delete(struct got_worktree *worktree,
2551     struct got_pathlist_head *ondisk_paths, int delete_local_mods,
2552     got_worktree_status_cb status_cb, void *status_arg,
2553     struct got_repository *repo)
2554 {
2555 	struct got_fileindex *fileindex = NULL;
2556 	char *fileindex_path = NULL;
2557 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2558 	struct got_pathlist_entry *pe;
2559 
2560 	err = lock_worktree(worktree, LOCK_EX);
2561 	if (err)
2562 		return err;
2563 
2564 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2565 	if (err)
2566 		goto done;
2567 
2568 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2569 		char *relpath;
2570 		err = got_path_skip_common_ancestor(&relpath,
2571 		    got_worktree_get_root_path(worktree), pe->path);
2572 		if (err)
2573 			break;
2574 		err = schedule_for_deletion(pe->path, fileindex, relpath,
2575 		    delete_local_mods, status_cb, status_arg, repo);
2576 		free(relpath);
2577 		if (err)
2578 			break;
2579 	}
2580 	sync_err = sync_fileindex(fileindex, fileindex_path);
2581 	if (sync_err && err == NULL)
2582 		err = sync_err;
2583 done:
2584 	free(fileindex_path);
2585 	if (fileindex)
2586 		got_fileindex_free(fileindex);
2587 	unlockerr = lock_worktree(worktree, LOCK_SH);
2588 	if (unlockerr && err == NULL)
2589 		err = unlockerr;
2590 	return err;
2591 }
2592 
2593 static const struct got_error *
2594 revert_file(struct got_worktree *worktree, struct got_fileindex *fileindex,
2595     const char *ondisk_path,
2596     got_worktree_checkout_cb progress_cb, void *progress_arg,
2597     struct got_repository *repo)
2598 {
2599 	const struct got_error *err = NULL;
2600 	char *relpath = NULL, *parent_path = NULL;
2601 	struct got_fileindex_entry *ie;
2602 	struct got_tree_object *tree = NULL;
2603 	struct got_object_id *tree_id = NULL;
2604 	const struct got_tree_entry *te;
2605 	char *tree_path = NULL, *te_name;
2606 	struct got_blob_object *blob = NULL;
2607 	unsigned char status;
2608 	struct stat sb;
2609 
2610 	err = got_path_skip_common_ancestor(&relpath,
2611 	    got_worktree_get_root_path(worktree), ondisk_path);
2612 	if (err)
2613 		goto done;
2614 
2615 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2616 	if (ie == NULL) {
2617 		err = got_error(GOT_ERR_BAD_PATH);
2618 		goto done;
2619 	}
2620 
2621 	/* Construct in-repository path of tree which contains this blob. */
2622 	err = got_path_dirname(&parent_path, ie->path);
2623 	if (err) {
2624 		if (err->code != GOT_ERR_BAD_PATH)
2625 			goto done;
2626 		parent_path = strdup("/");
2627 		if (parent_path == NULL) {
2628 			err = got_error_from_errno("strdup");
2629 			goto done;
2630 		}
2631 	}
2632 	if (got_path_is_root_dir(worktree->path_prefix)) {
2633 		tree_path = strdup(parent_path);
2634 		if (tree_path == NULL) {
2635 			err = got_error_from_errno("strdup");
2636 			goto done;
2637 		}
2638 	} else {
2639 		if (got_path_is_root_dir(parent_path)) {
2640 			tree_path = strdup(worktree->path_prefix);
2641 			if (tree_path == NULL) {
2642 				err = got_error_from_errno("strdup");
2643 				goto done;
2644 			}
2645 		} else {
2646 			if (asprintf(&tree_path, "%s/%s",
2647 			    worktree->path_prefix, parent_path) == -1) {
2648 				err = got_error_from_errno("asprintf");
2649 				goto done;
2650 			}
2651 		}
2652 	}
2653 
2654 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2655 	if (err)
2656 		goto done;
2657 	if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
2658 		sb.st_mode = got_fileindex_perms_to_st(ie);
2659 
2660 	err = got_object_id_by_path(&tree_id, repo, worktree->base_commit_id,
2661 	    tree_path);
2662 	if (err) {
2663 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
2664 		    status == GOT_STATUS_ADD))
2665 			goto done;
2666 	} else {
2667 		err = got_object_open_as_tree(&tree, repo, tree_id);
2668 		if (err)
2669 			goto done;
2670 
2671 		te_name = basename(ie->path);
2672 		if (te_name == NULL) {
2673 			err = got_error_from_errno2("basename", ie->path);
2674 			goto done;
2675 		}
2676 
2677 		te = got_object_tree_find_entry(tree, te_name);
2678 		if (te == NULL && status != GOT_STATUS_ADD) {
2679 			err = got_error(GOT_ERR_NO_TREE_ENTRY);
2680 			goto done;
2681 		}
2682 	}
2683 
2684 	switch (status) {
2685 	case GOT_STATUS_ADD:
2686 		err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT, ie->path);
2687 		if (err)
2688 			goto done;
2689 		got_fileindex_entry_remove(fileindex, ie);
2690 		break;
2691 	case GOT_STATUS_DELETE:
2692 	case GOT_STATUS_MODIFY:
2693 	case GOT_STATUS_CONFLICT:
2694 	case GOT_STATUS_MISSING: {
2695 		struct got_object_id id;
2696 		memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2697 		err = got_object_open_as_blob(&blob, repo, &id, 8192);
2698 		if (err)
2699 			goto done;
2700 		err = install_blob(worktree, ondisk_path, ie->path,
2701 		    te->mode, sb.st_mode, blob, 0, 1, repo, progress_cb,
2702 		    progress_arg);
2703 		if (err)
2704 			goto done;
2705 		if (status == GOT_STATUS_DELETE) {
2706 			err = update_blob_fileindex_entry(worktree,
2707 			    fileindex, ie, ondisk_path, ie->path, blob, 1);
2708 			if (err)
2709 				goto done;
2710 		}
2711 		break;
2712 	}
2713 	default:
2714 			goto done;
2715 	}
2716 done:
2717 	free(relpath);
2718 	free(parent_path);
2719 	free(tree_path);
2720 	if (blob)
2721 		got_object_blob_close(blob);
2722 	if (tree)
2723 		got_object_tree_close(tree);
2724 	free(tree_id);
2725 	return err;
2726 }
2727 
2728 const struct got_error *
2729 got_worktree_revert(struct got_worktree *worktree,
2730     struct got_pathlist_head *ondisk_paths,
2731     got_worktree_checkout_cb progress_cb, void *progress_arg,
2732     struct got_repository *repo)
2733 {
2734 	struct got_fileindex *fileindex = NULL;
2735 	char *fileindex_path = NULL;
2736 	const struct got_error *err = NULL, *unlockerr = NULL;
2737 	const struct got_error *sync_err = NULL;
2738 	struct got_pathlist_entry *pe;
2739 
2740 	err = lock_worktree(worktree, LOCK_EX);
2741 	if (err)
2742 		return err;
2743 
2744 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2745 	if (err)
2746 		goto done;
2747 
2748 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2749 		err = revert_file(worktree, fileindex, pe->path,
2750 		    progress_cb, progress_arg, repo);
2751 		if (err)
2752 			break;
2753 	}
2754 	sync_err = sync_fileindex(fileindex, fileindex_path);
2755 	if (sync_err && err == NULL)
2756 		err = sync_err;
2757 done:
2758 	free(fileindex_path);
2759 	if (fileindex)
2760 		got_fileindex_free(fileindex);
2761 	unlockerr = lock_worktree(worktree, LOCK_SH);
2762 	if (unlockerr && err == NULL)
2763 		err = unlockerr;
2764 	return err;
2765 }
2766 
2767 static void
2768 free_commitable(struct got_commitable *ct)
2769 {
2770 	free(ct->path);
2771 	free(ct->in_repo_path);
2772 	free(ct->ondisk_path);
2773 	free(ct->blob_id);
2774 	free(ct->base_blob_id);
2775 	free(ct->base_commit_id);
2776 	free(ct);
2777 }
2778 
2779 struct collect_commitables_arg {
2780 	struct got_pathlist_head *commitable_paths;
2781 	struct got_repository *repo;
2782 	struct got_worktree *worktree;
2783 };
2784 
2785 static const struct got_error *
2786 collect_commitables(void *arg, unsigned char status, const char *relpath,
2787     struct got_object_id *blob_id, struct got_object_id *commit_id)
2788 {
2789 	struct collect_commitables_arg *a = arg;
2790 	const struct got_error *err = NULL;
2791 	struct got_commitable *ct = NULL;
2792 	struct got_pathlist_entry *new = NULL;
2793 	char *parent_path = NULL, *path = NULL;
2794 	struct stat sb;
2795 
2796 	if (status == GOT_STATUS_CONFLICT)
2797 		return got_error(GOT_ERR_COMMIT_CONFLICT);
2798 
2799 	if (status != GOT_STATUS_MODIFY && status != GOT_STATUS_ADD &&
2800 	    status != GOT_STATUS_DELETE)
2801 		return NULL;
2802 
2803 	if (asprintf(&path, "/%s", relpath) == -1) {
2804 		err = got_error_from_errno("asprintf");
2805 		goto done;
2806 	}
2807 	if (strcmp(path, "/") == 0) {
2808 		parent_path = strdup("");
2809 		if (parent_path == NULL)
2810 			return got_error_from_errno("strdup");
2811 	} else {
2812 		err = got_path_dirname(&parent_path, path);
2813 		if (err)
2814 			return err;
2815 	}
2816 
2817 	ct = calloc(1, sizeof(*ct));
2818 	if (ct == NULL) {
2819 		err = got_error_from_errno("calloc");
2820 		goto done;
2821 	}
2822 
2823 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
2824 	    relpath) == -1) {
2825 		err = got_error_from_errno("asprintf");
2826 		goto done;
2827 	}
2828 	if (status == GOT_STATUS_DELETE) {
2829 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
2830 	} else {
2831 		if (lstat(ct->ondisk_path, &sb) != 0) {
2832 			err = got_error_from_errno2("lstat", ct->ondisk_path);
2833 			goto done;
2834 		}
2835 		ct->mode = sb.st_mode;
2836 	}
2837 
2838 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
2839 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
2840 	    relpath) == -1) {
2841 		err = got_error_from_errno("asprintf");
2842 		goto done;
2843 	}
2844 
2845 	ct->status = status;
2846 	ct->blob_id = NULL; /* will be filled in when blob gets created */
2847 	if (ct->status != GOT_STATUS_ADD) {
2848 		ct->base_blob_id = got_object_id_dup(blob_id);
2849 		if (ct->base_blob_id == NULL) {
2850 			err = got_error_from_errno("got_object_id_dup");
2851 			goto done;
2852 		}
2853 		ct->base_commit_id = got_object_id_dup(commit_id);
2854 		if (ct->base_commit_id == NULL) {
2855 			err = got_error_from_errno("got_object_id_dup");
2856 			goto done;
2857 		}
2858 	}
2859 	ct->path = strdup(path);
2860 	if (ct->path == NULL) {
2861 		err = got_error_from_errno("strdup");
2862 		goto done;
2863 	}
2864 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
2865 done:
2866 	if (ct && (err || new == NULL))
2867 		free_commitable(ct);
2868 	free(parent_path);
2869 	free(path);
2870 	return err;
2871 }
2872 
2873 static const struct got_error *write_tree(struct got_object_id **,
2874     struct got_tree_object *, const char *, struct got_pathlist_head *,
2875     got_worktree_status_cb status_cb, void *status_arg,
2876     struct got_repository *);
2877 
2878 static const struct got_error *
2879 write_subtree(struct got_object_id **new_subtree_id,
2880     struct got_tree_entry *te, const char *parent_path,
2881     struct got_pathlist_head *commitable_paths,
2882     got_worktree_status_cb status_cb, void *status_arg,
2883     struct got_repository *repo)
2884 {
2885 	const struct got_error *err = NULL;
2886 	struct got_tree_object *subtree;
2887 	char *subpath;
2888 
2889 	if (asprintf(&subpath, "%s%s%s", parent_path,
2890 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
2891 		return got_error_from_errno("asprintf");
2892 
2893 	err = got_object_open_as_tree(&subtree, repo, te->id);
2894 	if (err)
2895 		return err;
2896 
2897 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
2898 	    status_cb, status_arg, repo);
2899 	got_object_tree_close(subtree);
2900 	free(subpath);
2901 	return err;
2902 }
2903 
2904 static const struct got_error *
2905 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
2906 {
2907 	const struct got_error *err = NULL;
2908 	char *ct_parent_path = NULL;
2909 
2910 	*match = 0;
2911 
2912 	if (strchr(ct->in_repo_path, '/') == NULL) {
2913 		*match = got_path_is_root_dir(path);
2914 		return NULL;
2915 	}
2916 
2917 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
2918 	if (err)
2919 		return err;
2920 	*match = (strcmp(path, ct_parent_path) == 0);
2921 	free(ct_parent_path);
2922 	return err;
2923 }
2924 
2925 static mode_t
2926 get_ct_file_mode(struct got_commitable *ct)
2927 {
2928 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
2929 }
2930 
2931 static const struct got_error *
2932 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
2933     struct got_tree_entry *te, struct got_commitable *ct)
2934 {
2935 	const struct got_error *err = NULL;
2936 
2937 	*new_te = NULL;
2938 
2939 	err = got_object_tree_entry_dup(new_te, te);
2940 	if (err)
2941 		goto done;
2942 
2943 	(*new_te)->mode = get_ct_file_mode(ct);
2944 
2945 	free((*new_te)->id);
2946 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2947 	if ((*new_te)->id == NULL) {
2948 		err = got_error_from_errno("got_object_id_dup");
2949 		goto done;
2950 	}
2951 done:
2952 	if (err && *new_te) {
2953 		got_object_tree_entry_close(*new_te);
2954 		*new_te = NULL;
2955 	}
2956 	return err;
2957 }
2958 
2959 static const struct got_error *
2960 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
2961     struct got_commitable *ct)
2962 {
2963 	const struct got_error *err = NULL;
2964 	char *ct_name;
2965 
2966 	 *new_te = NULL;
2967 
2968 	*new_te = calloc(1, sizeof(**new_te));
2969 	if (*new_te == NULL)
2970 		return got_error_from_errno("calloc");
2971 
2972 	ct_name = basename(ct->path);
2973 	if (ct_name == NULL) {
2974 		err = got_error_from_errno2("basename", ct->path);
2975 		goto done;
2976 	}
2977 	(*new_te)->name = strdup(ct_name);
2978 	if ((*new_te)->name == NULL) {
2979 		err = got_error_from_errno("strdup");
2980 		goto done;
2981 	}
2982 
2983 	(*new_te)->mode = get_ct_file_mode(ct);
2984 
2985 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2986 	if ((*new_te)->id == NULL) {
2987 		err = got_error_from_errno("got_object_id_dup");
2988 		goto done;
2989 	}
2990 done:
2991 	if (err && *new_te) {
2992 		got_object_tree_entry_close(*new_te);
2993 		*new_te = NULL;
2994 	}
2995 	return err;
2996 }
2997 
2998 static const struct got_error *
2999 insert_tree_entry(struct got_tree_entry *new_te,
3000     struct got_pathlist_head *paths)
3001 {
3002 	const struct got_error *err = NULL;
3003 	struct got_pathlist_entry *new_pe;
3004 
3005 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
3006 	if (err)
3007 		return err;
3008 	if (new_pe == NULL)
3009 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
3010 	return NULL;
3011 }
3012 
3013 static const struct got_error *
3014 report_ct_status(struct got_commitable *ct,
3015     got_worktree_status_cb status_cb, void *status_arg)
3016 {
3017 	const char *ct_path = ct->path;
3018 	while (ct_path[0] == '/')
3019 		ct_path++;
3020 	return (*status_cb)(status_arg, ct->status, ct_path, ct->blob_id, NULL);
3021 }
3022 
3023 static const struct got_error *
3024 match_modified_subtree(int *modified, struct got_tree_entry *te,
3025     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
3026 {
3027 	const struct got_error *err = NULL;
3028 	struct got_pathlist_entry *pe;
3029 	char *te_path;
3030 
3031 	*modified = 0;
3032 
3033 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
3034 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
3035 	    te->name) == -1)
3036 		return got_error_from_errno("asprintf");
3037 
3038 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3039 		struct got_commitable *ct = pe->data;
3040 		*modified = got_path_is_child(ct->in_repo_path, te_path,
3041 		    strlen(te_path));
3042 		 if (*modified)
3043 			break;
3044 	}
3045 
3046 	free(te_path);
3047 	return err;
3048 }
3049 
3050 static const struct got_error *
3051 match_deleted_or_modified_ct(struct got_commitable **ctp,
3052     struct got_tree_entry *te, const char *base_tree_path,
3053     struct got_pathlist_head *commitable_paths)
3054 {
3055 	const struct got_error *err = NULL;
3056 	struct got_pathlist_entry *pe;
3057 
3058 	*ctp = NULL;
3059 
3060 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3061 		struct got_commitable *ct = pe->data;
3062 		char *ct_name = NULL;
3063 		int path_matches;
3064 
3065 		if (ct->status != GOT_STATUS_MODIFY &&
3066 		    ct->status != GOT_STATUS_DELETE)
3067 			continue;
3068 
3069 		if (got_object_id_cmp(ct->base_blob_id, te->id) != 0)
3070 			continue;
3071 
3072 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
3073 		 if (err)
3074 			return err;
3075 		if (!path_matches)
3076 			continue;
3077 
3078 		ct_name = basename(pe->path);
3079 		if (ct_name == NULL)
3080 			return got_error_from_errno2("basename", pe->path);
3081 
3082 		if (strcmp(te->name, ct_name) != 0)
3083 			continue;
3084 
3085 		*ctp = ct;
3086 		break;
3087 	}
3088 
3089 	return err;
3090 }
3091 
3092 static const struct got_error *
3093 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
3094     const char *child_path, const char *path_base_tree,
3095     struct got_pathlist_head *commitable_paths,
3096     got_worktree_status_cb status_cb, void *status_arg,
3097     struct got_repository *repo)
3098 {
3099 	const struct got_error *err = NULL;
3100 	struct got_tree_entry *new_te;
3101 	char *subtree_path;
3102 
3103 	*new_tep = NULL;
3104 
3105 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
3106 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
3107 	    child_path) == -1)
3108 		return got_error_from_errno("asprintf");
3109 
3110 	new_te = calloc(1, sizeof(*new_te));
3111 	new_te->mode = S_IFDIR;
3112 	new_te->name = strdup(child_path);
3113 	if (new_te->name == NULL) {
3114 		err = got_error_from_errno("strdup");
3115 		got_object_tree_entry_close(new_te);
3116 		goto done;
3117 	}
3118 	err = write_tree(&new_te->id, NULL, subtree_path,
3119 	    commitable_paths, status_cb, status_arg, repo);
3120 	if (err) {
3121 		got_object_tree_entry_close(new_te);
3122 		goto done;
3123 	}
3124 done:
3125 	free(subtree_path);
3126 	if (err == NULL)
3127 		*new_tep = new_te;
3128 	return err;
3129 }
3130 
3131 static const struct got_error *
3132 write_tree(struct got_object_id **new_tree_id,
3133     struct got_tree_object *base_tree, const char *path_base_tree,
3134     struct got_pathlist_head *commitable_paths,
3135     got_worktree_status_cb status_cb, void *status_arg,
3136     struct got_repository *repo)
3137 {
3138 	const struct got_error *err = NULL;
3139 	const struct got_tree_entries *base_entries = NULL;
3140 	struct got_pathlist_head paths;
3141 	struct got_tree_entries new_tree_entries;
3142 	struct got_tree_entry *te, *new_te = NULL;
3143 	struct got_pathlist_entry *pe;
3144 
3145 	TAILQ_INIT(&paths);
3146 	new_tree_entries.nentries = 0;
3147 	SIMPLEQ_INIT(&new_tree_entries.head);
3148 
3149 	/* Insert, and recurse into, newly added entries first. */
3150 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3151 		struct got_commitable *ct = pe->data;
3152 		char *child_path = NULL, *slash;
3153 
3154 		if (ct->status != GOT_STATUS_ADD ||
3155 		    (ct->flags & GOT_COMMITABLE_ADDED))
3156 			continue;
3157 
3158 		 if (!got_path_is_child(pe->path, path_base_tree,
3159 		     strlen(path_base_tree)))
3160 			continue;
3161 
3162 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
3163 		    pe->path);
3164 		if (err)
3165 			goto done;
3166 
3167 		slash = strchr(child_path, '/');
3168 		if (slash == NULL) {
3169 			err = alloc_added_blob_tree_entry(&new_te, ct);
3170 			if (err)
3171 				goto done;
3172 			err = report_ct_status(ct, status_cb, status_arg);
3173 			if (err)
3174 				goto done;
3175 			ct->flags |= GOT_COMMITABLE_ADDED;
3176 			err = insert_tree_entry(new_te, &paths);
3177 			if (err)
3178 				goto done;
3179 		} else {
3180 			*slash = '\0'; /* trim trailing path components */
3181 			if (base_tree == NULL ||
3182 			    got_object_tree_find_entry(base_tree, child_path)
3183 			    == NULL) {
3184 				err = make_subtree_for_added_blob(&new_te,
3185 				    child_path, path_base_tree,
3186 				    commitable_paths, status_cb, status_arg,
3187 				    repo);
3188 				if (err)
3189 					goto done;
3190 				err = insert_tree_entry(new_te, &paths);
3191 				if (err)
3192 					goto done;
3193 			}
3194 		}
3195 	}
3196 
3197 	if (base_tree) {
3198 		/* Handle modified and deleted entries. */
3199 		base_entries = got_object_tree_get_entries(base_tree);
3200 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
3201 			struct got_commitable *ct = NULL;
3202 
3203 			if (S_ISDIR(te->mode)) {
3204 				int modified;
3205 				err = got_object_tree_entry_dup(&new_te, te);
3206 				if (err)
3207 					goto done;
3208 				err = match_modified_subtree(&modified, te,
3209 				    path_base_tree, commitable_paths);
3210 				if (err)
3211 					goto done;
3212 				/* Avoid recursion into unmodified subtrees. */
3213 				if (modified) {
3214 					free(new_te->id);
3215 					err = write_subtree(&new_te->id, te,
3216 					    path_base_tree, commitable_paths,
3217 					    status_cb, status_arg, repo);
3218 					if (err)
3219 						goto done;
3220 				}
3221 				err = insert_tree_entry(new_te, &paths);
3222 				if (err)
3223 					goto done;
3224 				continue;
3225 			}
3226 
3227 			err = match_deleted_or_modified_ct(&ct, te,
3228 			    path_base_tree, commitable_paths);
3229 			if (ct) {
3230 				/* NB: Deleted entries get dropped here. */
3231 				if (ct->status == GOT_STATUS_MODIFY) {
3232 					err = alloc_modified_blob_tree_entry(
3233 					    &new_te, te, ct);
3234 					if (err)
3235 						goto done;
3236 					err = insert_tree_entry(new_te, &paths);
3237 					if (err)
3238 						goto done;
3239 				}
3240 				err = report_ct_status(ct, status_cb,
3241 				    status_arg);
3242 				if (err)
3243 					goto done;
3244 			} else {
3245 				/* Entry is unchanged; just copy it. */
3246 				err = got_object_tree_entry_dup(&new_te, te);
3247 				if (err)
3248 					goto done;
3249 				err = insert_tree_entry(new_te, &paths);
3250 				if (err)
3251 					goto done;
3252 			}
3253 		}
3254 	}
3255 
3256 	/* Write new list of entries; deleted entries have been dropped. */
3257 	TAILQ_FOREACH(pe, &paths, entry) {
3258 		struct got_tree_entry *te = pe->data;
3259 		new_tree_entries.nentries++;
3260 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
3261 	}
3262 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
3263 done:
3264 	got_object_tree_entries_close(&new_tree_entries);
3265 	got_pathlist_free(&paths);
3266 	return err;
3267 }
3268 
3269 static const struct got_error *
3270 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
3271     struct got_object_id *new_base_commit_id, struct got_fileindex *fileindex)
3272 {
3273 	const struct got_error *err = NULL;
3274 	struct got_pathlist_entry *pe;
3275 
3276 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3277 		struct got_fileindex_entry *ie;
3278 		struct got_commitable *ct = pe->data;
3279 
3280 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
3281 		if (ie) {
3282 			if (ct->status == GOT_STATUS_DELETE) {
3283 				got_fileindex_entry_remove(fileindex, ie);
3284 				got_fileindex_entry_free(ie);
3285 			} else
3286 				err = got_fileindex_entry_update(ie,
3287 				    ct->ondisk_path, ct->blob_id->sha1,
3288 				    new_base_commit_id->sha1, 1);
3289 		} else {
3290 			err = got_fileindex_entry_alloc(&ie,
3291 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
3292 			    new_base_commit_id->sha1);
3293 			if (err)
3294 				break;
3295 			err = got_fileindex_entry_add(fileindex, ie);
3296 			if (err)
3297 				break;
3298 		}
3299 	}
3300 	return err;
3301 }
3302 
3303 static const struct got_error *
3304 check_ct_out_of_date(struct got_commitable *ct, struct got_repository *repo,
3305 	struct got_object_id *head_commit_id)
3306 {
3307 	const struct got_error *err = NULL;
3308 	struct got_object_id *id = NULL;
3309 	struct got_commit_object *commit = NULL;
3310 	const char *ct_path = ct->in_repo_path;
3311 
3312 	while (ct_path[0] == '/')
3313 		ct_path++;
3314 
3315 	if (ct->status != GOT_STATUS_ADD) {
3316 		/* Trivial case: base commit == head commit */
3317 		if (got_object_id_cmp(ct->base_commit_id, head_commit_id) == 0)
3318 			return NULL;
3319 		/*
3320 		 * Ensure file content which local changes were based
3321 		 * on matches file content in the branch head.
3322 		 */
3323 		err = got_object_id_by_path(&id, repo, head_commit_id, ct_path);
3324 		if (err) {
3325 			if (err->code != GOT_ERR_NO_TREE_ENTRY)
3326 				goto done;
3327 			err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
3328 			goto done;
3329 		} else if (got_object_id_cmp(id, ct->base_blob_id) != 0)
3330 			err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
3331 	} else {
3332 		/* Require that added files don't exist in the branch head. */
3333 		err = got_object_id_by_path(&id, repo, head_commit_id, ct_path);
3334 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3335 			goto done;
3336 		err = id ? got_error(GOT_ERR_COMMIT_OUT_OF_DATE) : NULL;
3337 	}
3338 done:
3339 	if (commit)
3340 		got_object_commit_close(commit);
3341 	free(id);
3342 	return err;
3343 }
3344 
3345 const struct got_error *
3346 commit_worktree(struct got_object_id **new_commit_id,
3347     struct got_pathlist_head *commitable_paths,
3348     struct got_object_id *head_commit_id, struct got_worktree *worktree,
3349     const char *author, const char *committer,
3350     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3351     got_worktree_status_cb status_cb, void *status_arg,
3352     struct got_repository *repo)
3353 {
3354 	const struct got_error *err = NULL, *unlockerr = NULL;
3355 	struct got_pathlist_entry *pe;
3356 	const char *head_ref_name = NULL;
3357 	struct got_commit_object *head_commit = NULL;
3358 	struct got_reference *head_ref2 = NULL;
3359 	struct got_object_id *head_commit_id2 = NULL;
3360 	struct got_tree_object *head_tree = NULL;
3361 	struct got_object_id *new_tree_id = NULL;
3362 	struct got_object_id_queue parent_ids;
3363 	struct got_object_qid *pid = NULL;
3364 	char *logmsg = NULL;
3365 
3366 	*new_commit_id = NULL;
3367 
3368 	SIMPLEQ_INIT(&parent_ids);
3369 
3370 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
3371 	if (err)
3372 		goto done;
3373 
3374 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
3375 	if (err)
3376 		goto done;
3377 
3378 	if (commit_msg_cb != NULL) {
3379 		err = commit_msg_cb(commitable_paths, &logmsg, commit_arg);
3380 		if (err)
3381 			goto done;
3382 	}
3383 
3384 	if (logmsg == NULL || strlen(logmsg) == 0) {
3385 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
3386 		goto done;
3387 	}
3388 
3389 	/* Create blobs from added and modified files and record their IDs. */
3390 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3391 		struct got_commitable *ct = pe->data;
3392 		char *ondisk_path;
3393 
3394 		if (ct->status != GOT_STATUS_ADD &&
3395 		    ct->status != GOT_STATUS_MODIFY)
3396 			continue;
3397 
3398 		if (asprintf(&ondisk_path, "%s/%s",
3399 		    worktree->root_path, pe->path) == -1) {
3400 			err = got_error_from_errno("asprintf");
3401 			goto done;
3402 		}
3403 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
3404 		free(ondisk_path);
3405 		if (err)
3406 			goto done;
3407 	}
3408 
3409 	/* Recursively write new tree objects. */
3410 	err = write_tree(&new_tree_id, head_tree, "/", commitable_paths,
3411 	    status_cb, status_arg, repo);
3412 	if (err)
3413 		goto done;
3414 
3415 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
3416 	if (err)
3417 		goto done;
3418 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
3419 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
3420 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
3421 	got_object_qid_free(pid);
3422 	if (logmsg != NULL)
3423 		free(logmsg);
3424 	if (err)
3425 		goto done;
3426 
3427 	/* Check if a concurrent commit to our branch has occurred. */
3428 	head_ref_name = got_worktree_get_head_ref_name(worktree);
3429 	if (head_ref_name == NULL) {
3430 		err = got_error_from_errno("got_worktree_get_head_ref_name");
3431 		goto done;
3432 	}
3433 	/* Lock the reference here to prevent concurrent modification. */
3434 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
3435 	if (err)
3436 		goto done;
3437 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
3438 	if (err)
3439 		goto done;
3440 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
3441 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
3442 		goto done;
3443 	}
3444 	/* Update branch head in repository. */
3445 	err = got_ref_change_ref(head_ref2, *new_commit_id);
3446 	if (err)
3447 		goto done;
3448 	err = got_ref_write(head_ref2, repo);
3449 	if (err)
3450 		goto done;
3451 
3452 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
3453 	if (err)
3454 		goto done;
3455 
3456 	err = ref_base_commit(worktree, repo);
3457 	if (err)
3458 		goto done;
3459 done:
3460 	if (head_tree)
3461 		got_object_tree_close(head_tree);
3462 	if (head_commit)
3463 		got_object_commit_close(head_commit);
3464 	free(head_commit_id2);
3465 	if (head_ref2) {
3466 		unlockerr = got_ref_unlock(head_ref2);
3467 		if (unlockerr && err == NULL)
3468 			err = unlockerr;
3469 		got_ref_close(head_ref2);
3470 	}
3471 	return err;
3472 }
3473 
3474 static const struct got_error *
3475 check_path_is_commitable(const char *path,
3476     struct got_pathlist_head *commitable_paths)
3477 {
3478 	struct got_pathlist_entry *cpe = NULL;
3479 	size_t path_len = strlen(path);
3480 
3481 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
3482 		struct got_commitable *ct = cpe->data;
3483 		const char *ct_path = ct->path;
3484 
3485 		while (ct_path[0] == '/')
3486 			ct_path++;
3487 
3488 		if (strcmp(path, ct_path) == 0 ||
3489 		    got_path_is_child(ct_path, path, path_len))
3490 			break;
3491 	}
3492 
3493 	if (cpe == NULL)
3494 		return got_error_path(path, GOT_ERR_BAD_PATH);
3495 
3496 	return NULL;
3497 }
3498 
3499 const struct got_error *
3500 got_worktree_commit(struct got_object_id **new_commit_id,
3501     struct got_worktree *worktree, struct got_pathlist_head *paths,
3502     const char *author, const char *committer,
3503     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3504     got_worktree_status_cb status_cb, void *status_arg,
3505     struct got_repository *repo)
3506 {
3507 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
3508 	struct got_fileindex *fileindex = NULL;
3509 	char *fileindex_path = NULL;
3510 	struct got_pathlist_head commitable_paths;
3511 	struct collect_commitables_arg cc_arg;
3512 	struct got_pathlist_entry *pe;
3513 	struct got_reference *head_ref = NULL;
3514 	struct got_object_id *head_commit_id = NULL;
3515 
3516 	*new_commit_id = NULL;
3517 
3518 	TAILQ_INIT(&commitable_paths);
3519 
3520 	err = lock_worktree(worktree, LOCK_EX);
3521 	if (err)
3522 		goto done;
3523 
3524 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
3525 	if (err)
3526 		goto done;
3527 
3528 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
3529 	if (err)
3530 		goto done;
3531 
3532 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3533 	if (err)
3534 		goto done;
3535 
3536 	cc_arg.commitable_paths = &commitable_paths;
3537 	cc_arg.worktree = worktree;
3538 	cc_arg.repo = repo;
3539 	TAILQ_FOREACH(pe, paths, entry) {
3540 		err = worktree_status(worktree, pe->path, fileindex, repo,
3541 		    collect_commitables, &cc_arg, NULL, NULL);
3542 		if (err)
3543 			goto done;
3544 	}
3545 
3546 	if (TAILQ_EMPTY(&commitable_paths)) {
3547 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
3548 		goto done;
3549 	}
3550 
3551 	TAILQ_FOREACH(pe, paths, entry) {
3552 		err = check_path_is_commitable(pe->path, &commitable_paths);
3553 		if (err)
3554 			goto done;
3555 	}
3556 
3557 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3558 		struct got_commitable *ct = pe->data;
3559 		err = check_ct_out_of_date(ct, repo, head_commit_id);
3560 		if (err)
3561 			goto done;
3562 	}
3563 
3564 	err = commit_worktree(new_commit_id, &commitable_paths,
3565 	    head_commit_id, worktree, author, committer,
3566 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
3567 	if (err)
3568 		goto done;
3569 
3570 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
3571 	    fileindex);
3572 	sync_err = sync_fileindex(fileindex, fileindex_path);
3573 	if (sync_err && err == NULL)
3574 		err = sync_err;
3575 done:
3576 	if (fileindex)
3577 		got_fileindex_free(fileindex);
3578 	free(fileindex_path);
3579 	unlockerr = lock_worktree(worktree, LOCK_SH);
3580 	if (unlockerr && err == NULL)
3581 		err = unlockerr;
3582 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3583 		struct got_commitable *ct = pe->data;
3584 		free_commitable(ct);
3585 	}
3586 	got_pathlist_free(&commitable_paths);
3587 	return err;
3588 }
3589 
3590 const char *
3591 got_commitable_get_path(struct got_commitable *ct)
3592 {
3593 	return ct->path;
3594 }
3595 
3596 unsigned int
3597 got_commitable_get_status(struct got_commitable *ct)
3598 {
3599 	return ct->status;
3600 }
3601 
3602 struct check_rebase_ok_arg {
3603 	struct got_worktree *worktree;
3604 	struct got_repository *repo;
3605 };
3606 
3607 static const struct got_error *
3608 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
3609 {
3610 	const struct got_error *err = NULL;
3611 	struct check_rebase_ok_arg *a = arg;
3612 	unsigned char status;
3613 	struct stat sb;
3614 	char *ondisk_path;
3615 
3616 	/* Reject rebase of a work tree with mixed base commits. */
3617 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
3618 	    SHA1_DIGEST_LENGTH))
3619 		return got_error(GOT_ERR_MIXED_COMMITS);
3620 
3621 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
3622 	    == -1)
3623 		return got_error_from_errno("asprintf");
3624 
3625 	/* Reject rebase of a work tree with modified or conflicted files. */
3626 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
3627 	free(ondisk_path);
3628 	if (err)
3629 		return err;
3630 
3631 	if (status != GOT_STATUS_NO_CHANGE)
3632 		return got_error(GOT_ERR_MODIFIED);
3633 
3634 	return NULL;
3635 }
3636 
3637 const struct got_error *
3638 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
3639     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
3640     struct got_worktree *worktree, struct got_reference *branch,
3641     struct got_repository *repo)
3642 {
3643 	const struct got_error *err = NULL;
3644 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
3645 	char *branch_ref_name = NULL;
3646 	char *fileindex_path = NULL;
3647 	struct check_rebase_ok_arg ok_arg;
3648 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
3649 
3650 	*new_base_branch_ref = NULL;
3651 	*tmp_branch = NULL;
3652 	*fileindex = NULL;
3653 
3654 	err = lock_worktree(worktree, LOCK_EX);
3655 	if (err)
3656 		return err;
3657 
3658 	err = open_fileindex(fileindex, &fileindex_path, worktree);
3659 	if (err)
3660 		goto done;
3661 
3662 	ok_arg.worktree = worktree;
3663 	ok_arg.repo = repo;
3664 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
3665 	    &ok_arg);
3666 	if (err)
3667 		goto done;
3668 
3669 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3670 	if (err)
3671 		goto done;
3672 
3673 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
3674 	if (err)
3675 		goto done;
3676 
3677 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
3678 	if (err)
3679 		goto done;
3680 
3681 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
3682 	    0);
3683 	if (err)
3684 		goto done;
3685 
3686 	err = got_ref_alloc_symref(new_base_branch_ref,
3687 	    new_base_branch_ref_name, wt_branch);
3688 	if (err)
3689 		goto done;
3690 	err = got_ref_write(*new_base_branch_ref, repo);
3691 	if (err)
3692 		goto done;
3693 
3694 	/* TODO Lock original branch's ref while rebasing? */
3695 
3696 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
3697 	if (err)
3698 		goto done;
3699 
3700 	err = got_ref_write(branch_ref, repo);
3701 	if (err)
3702 		goto done;
3703 
3704 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
3705 	    worktree->base_commit_id);
3706 	if (err)
3707 		goto done;
3708 	err = got_ref_write(*tmp_branch, repo);
3709 	if (err)
3710 		goto done;
3711 
3712 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
3713 	if (err)
3714 		goto done;
3715 done:
3716 	free(fileindex_path);
3717 	free(tmp_branch_name);
3718 	free(new_base_branch_ref_name);
3719 	free(branch_ref_name);
3720 	if (branch_ref)
3721 		got_ref_close(branch_ref);
3722 	if (wt_branch)
3723 		got_ref_close(wt_branch);
3724 	if (err) {
3725 		if (*new_base_branch_ref) {
3726 			got_ref_close(*new_base_branch_ref);
3727 			*new_base_branch_ref = NULL;
3728 		}
3729 		if (*tmp_branch) {
3730 			got_ref_close(*tmp_branch);
3731 			*tmp_branch = NULL;
3732 		}
3733 		if (*fileindex) {
3734 			got_fileindex_free(*fileindex);
3735 			*fileindex = NULL;
3736 		}
3737 		lock_worktree(worktree, LOCK_SH);
3738 	}
3739 	return err;
3740 }
3741 
3742 const struct got_error *
3743 got_worktree_rebase_continue(struct got_object_id **commit_id,
3744     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
3745     struct got_reference **branch, struct got_fileindex **fileindex,
3746     struct got_worktree *worktree, struct got_repository *repo)
3747 {
3748 	const struct got_error *err;
3749 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
3750 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
3751 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
3752 	char *fileindex_path = NULL;
3753 
3754 	*commit_id = NULL;
3755 	*new_base_branch = NULL;
3756 	*tmp_branch = NULL;
3757 	*branch = NULL;
3758 	*fileindex = NULL;
3759 
3760 	err = lock_worktree(worktree, LOCK_EX);
3761 	if (err)
3762 		return err;
3763 
3764 	err = open_fileindex(fileindex, &fileindex_path, worktree);
3765 	if (err)
3766 		goto done;
3767 
3768 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3769 	if (err)
3770 		return err;
3771 
3772 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
3773 	if (err)
3774 		goto done;
3775 
3776 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
3777 	if (err)
3778 		goto done;
3779 
3780 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
3781 	if (err)
3782 		goto done;
3783 
3784 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
3785 	if (err)
3786 		goto done;
3787 
3788 	err = got_ref_open(branch, repo,
3789 	    got_ref_get_symref_target(branch_ref), 0);
3790 	if (err)
3791 		goto done;
3792 
3793 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
3794 	if (err)
3795 		goto done;
3796 
3797 	err = got_ref_resolve(commit_id, repo, commit_ref);
3798 	if (err)
3799 		goto done;
3800 
3801 	err = got_ref_open(new_base_branch, repo,
3802 	    new_base_branch_ref_name, 0);
3803 	if (err)
3804 		goto done;
3805 
3806 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
3807 	if (err)
3808 		goto done;
3809 done:
3810 	free(commit_ref_name);
3811 	free(branch_ref_name);
3812 	free(fileindex_path);
3813 	if (commit_ref)
3814 		got_ref_close(commit_ref);
3815 	if (branch_ref)
3816 		got_ref_close(branch_ref);
3817 	if (err) {
3818 		free(*commit_id);
3819 		*commit_id = NULL;
3820 		if (*tmp_branch) {
3821 			got_ref_close(*tmp_branch);
3822 			*tmp_branch = NULL;
3823 		}
3824 		if (*new_base_branch) {
3825 			got_ref_close(*new_base_branch);
3826 			*new_base_branch = NULL;
3827 		}
3828 		if (*branch) {
3829 			got_ref_close(*branch);
3830 			*branch = NULL;
3831 		}
3832 		if (*fileindex) {
3833 			got_fileindex_free(*fileindex);
3834 			*fileindex = NULL;
3835 		}
3836 		lock_worktree(worktree, LOCK_SH);
3837 	}
3838 	return err;
3839 }
3840 
3841 const struct got_error *
3842 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
3843 {
3844 	const struct got_error *err;
3845 	char *tmp_branch_name = NULL;
3846 
3847 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3848 	if (err)
3849 		return err;
3850 
3851 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
3852 	free(tmp_branch_name);
3853 	return NULL;
3854 }
3855 
3856 static const struct got_error *
3857 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
3858     char **logmsg, void *arg)
3859 {
3860 	*logmsg = arg;
3861 	return NULL;
3862 }
3863 
3864 static const struct got_error *
3865 rebase_status(void *arg, unsigned char status, const char *path,
3866     struct got_object_id *blob_id, struct got_object_id *commit_id)
3867 {
3868 	return NULL;
3869 }
3870 
3871 struct collect_merged_paths_arg {
3872 	got_worktree_checkout_cb progress_cb;
3873 	void *progress_arg;
3874 	struct got_pathlist_head *merged_paths;
3875 };
3876 
3877 static const struct got_error *
3878 collect_merged_paths(void *arg, unsigned char status, const char *path)
3879 {
3880 	const struct got_error *err;
3881 	struct collect_merged_paths_arg *a = arg;
3882 	char *p;
3883 	struct got_pathlist_entry *new;
3884 
3885 	err = (*a->progress_cb)(a->progress_arg, status, path);
3886 	if (err)
3887 		return err;
3888 
3889 	if (status != GOT_STATUS_MERGE &&
3890 	    status != GOT_STATUS_ADD &&
3891 	    status != GOT_STATUS_DELETE &&
3892 	    status != GOT_STATUS_CONFLICT)
3893 		return NULL;
3894 
3895 	p = strdup(path);
3896 	if (p == NULL)
3897 		return got_error_from_errno("strdup");
3898 
3899 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
3900 	if (err || new == NULL)
3901 		free(p);
3902 	return err;
3903 }
3904 
3905 void
3906 got_worktree_rebase_pathlist_free(struct got_pathlist_head *merged_paths)
3907 {
3908 	struct got_pathlist_entry *pe;
3909 
3910 	TAILQ_FOREACH(pe, merged_paths, entry)
3911 		free((char *)pe->path);
3912 
3913 	got_pathlist_free(merged_paths);
3914 }
3915 
3916 static const struct got_error *
3917 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
3918     struct got_repository *repo)
3919 {
3920 	const struct got_error *err;
3921 	struct got_reference *commit_ref = NULL;
3922 
3923 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
3924 	if (err) {
3925 		if (err->code != GOT_ERR_NOT_REF)
3926 			goto done;
3927 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
3928 		if (err)
3929 			goto done;
3930 		err = got_ref_write(commit_ref, repo);
3931 		if (err)
3932 			goto done;
3933 	} else {
3934 		struct got_object_id *stored_id;
3935 		int cmp;
3936 
3937 		err = got_ref_resolve(&stored_id, repo, commit_ref);
3938 		if (err)
3939 			goto done;
3940 		cmp = got_object_id_cmp(commit_id, stored_id);
3941 		free(stored_id);
3942 		if (cmp != 0) {
3943 			err = got_error(GOT_ERR_REBASE_COMMITID);
3944 			goto done;
3945 		}
3946 	}
3947 done:
3948 	if (commit_ref)
3949 		got_ref_close(commit_ref);
3950 	return err;
3951 }
3952 
3953 static const struct got_error *
3954 rebase_merge_files(struct got_pathlist_head *merged_paths,
3955     const char *commit_ref_name, struct got_worktree *worktree,
3956     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
3957     struct got_object_id *commit_id, struct got_repository *repo,
3958     got_worktree_checkout_cb progress_cb, void *progress_arg,
3959     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
3960 {
3961 	const struct got_error *err;
3962 	struct got_reference *commit_ref = NULL;
3963 	struct collect_merged_paths_arg cmp_arg;
3964 	char *fileindex_path;
3965 
3966 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
3967 
3968 	err = get_fileindex_path(&fileindex_path, worktree);
3969 	if (err)
3970 		return err;
3971 
3972 	cmp_arg.progress_cb = progress_cb;
3973 	cmp_arg.progress_arg = progress_arg;
3974 	cmp_arg.merged_paths = merged_paths;
3975 	err = merge_files(worktree, fileindex, fileindex_path,
3976 	    parent_commit_id, commit_id, repo, collect_merged_paths,
3977 	    &cmp_arg, cancel_cb, cancel_arg);
3978 	if (commit_ref)
3979 		got_ref_close(commit_ref);
3980 	return err;
3981 }
3982 
3983 const struct got_error *
3984 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
3985     struct got_worktree *worktree, struct got_fileindex *fileindex,
3986     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
3987     struct got_repository *repo,
3988     got_worktree_checkout_cb progress_cb, void *progress_arg,
3989     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
3990 {
3991 	const struct got_error *err;
3992 	char *commit_ref_name;
3993 
3994 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
3995 	if (err)
3996 		return err;
3997 
3998 	err = store_commit_id(commit_ref_name, commit_id, repo);
3999 	if (err)
4000 		goto done;
4001 
4002 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4003 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4004 	    progress_arg, cancel_cb, cancel_arg);
4005 done:
4006 	free(commit_ref_name);
4007 	return err;
4008 }
4009 
4010 const struct got_error *
4011 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
4012     struct got_worktree *worktree, struct got_fileindex *fileindex,
4013     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
4014     struct got_repository *repo,
4015     got_worktree_checkout_cb progress_cb, void *progress_arg,
4016     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
4017 {
4018 	const struct got_error *err;
4019 	char *commit_ref_name;
4020 
4021 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4022 	if (err)
4023 		return err;
4024 
4025 	err = store_commit_id(commit_ref_name, commit_id, repo);
4026 	if (err)
4027 		goto done;
4028 
4029 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4030 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4031 	    progress_arg, cancel_cb, cancel_arg);
4032 done:
4033 	free(commit_ref_name);
4034 	return err;
4035 }
4036 
4037 static const struct got_error *
4038 rebase_commit(struct got_object_id **new_commit_id,
4039     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
4040     struct got_worktree *worktree, struct got_fileindex *fileindex,
4041     struct got_reference *tmp_branch, struct got_commit_object *orig_commit,
4042     const char *new_logmsg, struct got_repository *repo)
4043 {
4044 	const struct got_error *err, *sync_err;
4045 	struct got_pathlist_head commitable_paths;
4046 	struct collect_commitables_arg cc_arg;
4047 	char *fileindex_path = NULL;
4048 	struct got_reference *head_ref = NULL;
4049 	struct got_object_id *head_commit_id = NULL;
4050 	char *logmsg = NULL;
4051 
4052 	TAILQ_INIT(&commitable_paths);
4053 	*new_commit_id = NULL;
4054 
4055 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
4056 
4057 	err = get_fileindex_path(&fileindex_path, worktree);
4058 	if (err)
4059 		return err;
4060 
4061 	cc_arg.commitable_paths = &commitable_paths;
4062 	cc_arg.worktree = worktree;
4063 	cc_arg.repo = repo;
4064 	/*
4065 	 * If possible get the status of individual files directly to
4066 	 * avoid crawling the entire work tree once per rebased commit.
4067 	 * TODO: Ideally, merged_paths would contain a list of commitables
4068 	 * we could use so we could skip worktree_status() entirely.
4069 	 */
4070 	if (merged_paths) {
4071 		struct got_pathlist_entry *pe;
4072 		if (TAILQ_EMPTY(merged_paths)) {
4073 			err = got_error(GOT_ERR_NO_MERGED_PATHS);
4074 			goto done;
4075 		}
4076 		TAILQ_FOREACH(pe, merged_paths, entry) {
4077 			err = worktree_status(worktree, pe->path, fileindex,
4078 			    repo, collect_commitables, &cc_arg, NULL, NULL);
4079 			if (err)
4080 				goto done;
4081 		}
4082 	} else {
4083 		err = worktree_status(worktree, "", fileindex, repo,
4084 		    collect_commitables, &cc_arg, NULL, NULL);
4085 		if (err)
4086 			goto done;
4087 	}
4088 
4089 	if (TAILQ_EMPTY(&commitable_paths)) {
4090 		/* No-op change; commit will be elided. */
4091 		err = got_ref_delete(commit_ref, repo);
4092 		if (err)
4093 			goto done;
4094 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
4095 		goto done;
4096 	}
4097 
4098 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
4099 	if (err)
4100 		goto done;
4101 
4102 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
4103 	if (err)
4104 		goto done;
4105 
4106 	if (new_logmsg)
4107 		logmsg = strdup(new_logmsg);
4108 	else
4109 		logmsg = strdup(got_object_commit_get_logmsg(orig_commit));
4110 	if (logmsg == NULL)
4111 		return got_error_from_errno("strdup");
4112 
4113 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
4114 	    worktree, got_object_commit_get_author(orig_commit),
4115 	    got_object_commit_get_committer(orig_commit),
4116 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
4117 	if (err)
4118 		goto done;
4119 
4120 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
4121 	if (err)
4122 		goto done;
4123 
4124 	err = got_ref_delete(commit_ref, repo);
4125 	if (err)
4126 		goto done;
4127 
4128 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
4129 	    fileindex);
4130 	sync_err = sync_fileindex(fileindex, fileindex_path);
4131 	if (sync_err && err == NULL)
4132 		err = sync_err;
4133 done:
4134 	free(fileindex_path);
4135 	free(head_commit_id);
4136 	if (head_ref)
4137 		got_ref_close(head_ref);
4138 	if (err) {
4139 		free(*new_commit_id);
4140 		*new_commit_id = NULL;
4141 	}
4142 	return err;
4143 }
4144 
4145 const struct got_error *
4146 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
4147     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4148     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4149     struct got_commit_object *orig_commit,
4150     struct got_object_id *orig_commit_id, struct got_repository *repo)
4151 {
4152 	const struct got_error *err;
4153 	char *commit_ref_name;
4154 	struct got_reference *commit_ref = NULL;
4155 	struct got_object_id *commit_id = NULL;
4156 
4157 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4158 	if (err)
4159 		return err;
4160 
4161 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4162 	if (err)
4163 		goto done;
4164 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4165 	if (err)
4166 		goto done;
4167 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4168 		err = got_error(GOT_ERR_REBASE_COMMITID);
4169 		goto done;
4170 	}
4171 
4172 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4173 	    worktree, fileindex, tmp_branch, orig_commit, NULL, repo);
4174 done:
4175 	if (commit_ref)
4176 		got_ref_close(commit_ref);
4177 	free(commit_ref_name);
4178 	free(commit_id);
4179 	return err;
4180 }
4181 
4182 const struct got_error *
4183 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
4184     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4185     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4186     struct got_commit_object *orig_commit,
4187     struct got_object_id *orig_commit_id, const char *new_logmsg,
4188     struct got_repository *repo)
4189 {
4190 	const struct got_error *err;
4191 	char *commit_ref_name;
4192 	struct got_reference *commit_ref = NULL;
4193 	struct got_object_id *commit_id = NULL;
4194 
4195 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4196 	if (err)
4197 		return err;
4198 
4199 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4200 	if (err)
4201 		goto done;
4202 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4203 	if (err)
4204 		goto done;
4205 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4206 		err = got_error(GOT_ERR_HISTEDIT_COMMITID);
4207 		goto done;
4208 	}
4209 
4210 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4211 	    worktree, fileindex, tmp_branch, orig_commit, new_logmsg, repo);
4212 done:
4213 	if (commit_ref)
4214 		got_ref_close(commit_ref);
4215 	free(commit_ref_name);
4216 	free(commit_id);
4217 	return err;
4218 }
4219 
4220 const struct got_error *
4221 got_worktree_rebase_postpone(struct got_worktree *worktree,
4222     struct got_fileindex *fileindex)
4223 {
4224 	if (fileindex)
4225 		got_fileindex_free(fileindex);
4226 	return lock_worktree(worktree, LOCK_SH);
4227 }
4228 
4229 static const struct got_error *
4230 delete_ref(const char *name, struct got_repository *repo)
4231 {
4232 	const struct got_error *err;
4233 	struct got_reference *ref;
4234 
4235 	err = got_ref_open(&ref, repo, name, 0);
4236 	if (err) {
4237 		if (err->code == GOT_ERR_NOT_REF)
4238 			return NULL;
4239 		return err;
4240 	}
4241 
4242 	err = got_ref_delete(ref, repo);
4243 	got_ref_close(ref);
4244 	return err;
4245 }
4246 
4247 static const struct got_error *
4248 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
4249 {
4250 	const struct got_error *err;
4251 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
4252 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
4253 
4254 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4255 	if (err)
4256 		goto done;
4257 	err = delete_ref(tmp_branch_name, repo);
4258 	if (err)
4259 		goto done;
4260 
4261 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
4262 	if (err)
4263 		goto done;
4264 	err = delete_ref(new_base_branch_ref_name, repo);
4265 	if (err)
4266 		goto done;
4267 
4268 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
4269 	if (err)
4270 		goto done;
4271 	err = delete_ref(branch_ref_name, repo);
4272 	if (err)
4273 		goto done;
4274 
4275 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4276 	if (err)
4277 		goto done;
4278 	err = delete_ref(commit_ref_name, repo);
4279 	if (err)
4280 		goto done;
4281 
4282 done:
4283 	free(tmp_branch_name);
4284 	free(new_base_branch_ref_name);
4285 	free(branch_ref_name);
4286 	free(commit_ref_name);
4287 	return err;
4288 }
4289 
4290 const struct got_error *
4291 got_worktree_rebase_complete(struct got_worktree *worktree,
4292     struct got_fileindex *fileindex, struct got_reference *new_base_branch,
4293     struct got_reference *tmp_branch, struct got_reference *rebased_branch,
4294     struct got_repository *repo)
4295 {
4296 	const struct got_error *err, *unlockerr;
4297 	struct got_object_id *new_head_commit_id = NULL;
4298 
4299 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
4300 	if (err)
4301 		return err;
4302 
4303 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
4304 	if (err)
4305 		goto done;
4306 
4307 	err = got_ref_write(rebased_branch, repo);
4308 	if (err)
4309 		goto done;
4310 
4311 	err = got_worktree_set_head_ref(worktree, rebased_branch);
4312 	if (err)
4313 		goto done;
4314 
4315 	err = delete_rebase_refs(worktree, repo);
4316 done:
4317 	if (fileindex)
4318 		got_fileindex_free(fileindex);
4319 	free(new_head_commit_id);
4320 	unlockerr = lock_worktree(worktree, LOCK_SH);
4321 	if (unlockerr && err == NULL)
4322 		err = unlockerr;
4323 	return err;
4324 }
4325 
4326 struct collect_revertible_paths_arg {
4327 	struct got_pathlist_head *revertible_paths;
4328 	struct got_worktree *worktree;
4329 };
4330 
4331 static const struct got_error *
4332 collect_revertible_paths(void *arg, unsigned char status, const char *relpath,
4333     struct got_object_id *blob_id, struct got_object_id *commit_id)
4334 {
4335 	struct collect_revertible_paths_arg *a = arg;
4336 	const struct got_error *err = NULL;
4337 	struct got_pathlist_entry *new = NULL;
4338 	char *path = NULL;
4339 
4340 	if (status != GOT_STATUS_ADD &&
4341 	    status != GOT_STATUS_DELETE &&
4342 	    status != GOT_STATUS_MODIFY &&
4343 	    status != GOT_STATUS_CONFLICT &&
4344 	    status != GOT_STATUS_MISSING)
4345 		return NULL;
4346 
4347 	if (asprintf(&path, "%s/%s", a->worktree->root_path, relpath) == -1)
4348 		return got_error_from_errno("asprintf");
4349 
4350 	err = got_pathlist_insert(&new, a->revertible_paths, path, NULL);
4351 	if (err || new == NULL)
4352 		free(path);
4353 	return err;
4354 }
4355 
4356 const struct got_error *
4357 got_worktree_rebase_abort(struct got_worktree *worktree,
4358     struct got_fileindex *fileindex, struct got_repository *repo,
4359     struct got_reference *new_base_branch,
4360      got_worktree_checkout_cb progress_cb, void *progress_arg)
4361 {
4362 	const struct got_error *err, *unlockerr, *sync_err;
4363 	struct got_reference *resolved = NULL;
4364 	struct got_object_id *commit_id = NULL;
4365 	char *fileindex_path = NULL;
4366 	struct got_pathlist_head revertible_paths;
4367 	struct got_pathlist_entry *pe;
4368 	struct collect_revertible_paths_arg crp_arg;
4369 	struct got_object_id *tree_id = NULL;
4370 
4371 	TAILQ_INIT(&revertible_paths);
4372 
4373 	err = lock_worktree(worktree, LOCK_EX);
4374 	if (err)
4375 		return err;
4376 
4377 	err = got_ref_open(&resolved, repo,
4378 	    got_ref_get_symref_target(new_base_branch), 0);
4379 	if (err)
4380 		goto done;
4381 
4382 	err = got_worktree_set_head_ref(worktree, resolved);
4383 	if (err)
4384 		goto done;
4385 
4386 	/*
4387 	 * XXX commits to the base branch could have happened while
4388 	 * we were busy rebasing; should we store the original commit ID
4389 	 * when rebase begins and read it back here?
4390 	 */
4391 	err = got_ref_resolve(&commit_id, repo, resolved);
4392 	if (err)
4393 		goto done;
4394 
4395 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
4396 	if (err)
4397 		goto done;
4398 
4399 	err = got_object_id_by_path(&tree_id, repo,
4400 	    worktree->base_commit_id, worktree->path_prefix);
4401 	if (err)
4402 		goto done;
4403 
4404 	err = delete_rebase_refs(worktree, repo);
4405 	if (err)
4406 		goto done;
4407 
4408 	err = get_fileindex_path(&fileindex_path, worktree);
4409 	if (err)
4410 		goto done;
4411 
4412 	crp_arg.revertible_paths = &revertible_paths;
4413 	crp_arg.worktree = worktree;
4414 	err = worktree_status(worktree, "", fileindex, repo,
4415 	    collect_revertible_paths, &crp_arg, NULL, NULL);
4416 	if (err)
4417 		goto done;
4418 
4419 	TAILQ_FOREACH(pe, &revertible_paths, entry) {
4420 		err = revert_file(worktree, fileindex, pe->path,
4421 		    progress_cb, progress_arg, repo);
4422 		if (err)
4423 			goto sync;
4424 	}
4425 
4426 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
4427 	    repo, progress_cb, progress_arg, NULL, NULL);
4428 sync:
4429 	sync_err = sync_fileindex(fileindex, fileindex_path);
4430 	if (sync_err && err == NULL)
4431 		err = sync_err;
4432 done:
4433 	got_ref_close(resolved);
4434 	free(tree_id);
4435 	free(commit_id);
4436 	if (fileindex)
4437 		got_fileindex_free(fileindex);
4438 	free(fileindex_path);
4439 	TAILQ_FOREACH(pe, &revertible_paths, entry)
4440 		free((char *)pe->path);
4441 	got_pathlist_free(&revertible_paths);
4442 
4443 	unlockerr = lock_worktree(worktree, LOCK_SH);
4444 	if (unlockerr && err == NULL)
4445 		err = unlockerr;
4446 	return err;
4447 }
4448 
4449 const struct got_error *
4450 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
4451     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
4452     struct got_fileindex **fileindex, struct got_worktree *worktree,
4453     struct got_repository *repo)
4454 {
4455 	const struct got_error *err = NULL;
4456 	char *tmp_branch_name = NULL;
4457 	char *branch_ref_name = NULL;
4458 	char *base_commit_ref_name = NULL;
4459 	char *fileindex_path = NULL;
4460 	struct check_rebase_ok_arg ok_arg;
4461 	struct got_reference *wt_branch = NULL;
4462 	struct got_reference *base_commit_ref = NULL;
4463 
4464 	*tmp_branch = NULL;
4465 	*branch_ref = NULL;
4466 	*base_commit_id = NULL;
4467 	*fileindex = NULL;
4468 
4469 	err = lock_worktree(worktree, LOCK_EX);
4470 	if (err)
4471 		return err;
4472 
4473 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4474 	if (err)
4475 		goto done;
4476 
4477 	ok_arg.worktree = worktree;
4478 	ok_arg.repo = repo;
4479 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
4480 	    &ok_arg);
4481 	if (err)
4482 		goto done;
4483 
4484 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4485 	if (err)
4486 		goto done;
4487 
4488 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
4489 	if (err)
4490 		goto done;
4491 
4492 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
4493 	    worktree);
4494 	if (err)
4495 		goto done;
4496 
4497 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
4498 	    0);
4499 	if (err)
4500 		goto done;
4501 
4502 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
4503 	if (err)
4504 		goto done;
4505 
4506 	err = got_ref_write(*branch_ref, repo);
4507 	if (err)
4508 		goto done;
4509 
4510 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
4511 	    worktree->base_commit_id);
4512 	if (err)
4513 		goto done;
4514 	err = got_ref_write(base_commit_ref, repo);
4515 	if (err)
4516 		goto done;
4517 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
4518 	if (*base_commit_id == NULL) {
4519 		err = got_error_from_errno("got_object_id_dup");
4520 		goto done;
4521 	}
4522 
4523 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
4524 	    worktree->base_commit_id);
4525 	if (err)
4526 		goto done;
4527 	err = got_ref_write(*tmp_branch, repo);
4528 	if (err)
4529 		goto done;
4530 
4531 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
4532 	if (err)
4533 		goto done;
4534 done:
4535 	free(fileindex_path);
4536 	free(tmp_branch_name);
4537 	free(branch_ref_name);
4538 	free(base_commit_ref_name);
4539 	if (wt_branch)
4540 		got_ref_close(wt_branch);
4541 	if (err) {
4542 		if (*branch_ref) {
4543 			got_ref_close(*branch_ref);
4544 			*branch_ref = NULL;
4545 		}
4546 		if (*tmp_branch) {
4547 			got_ref_close(*tmp_branch);
4548 			*tmp_branch = NULL;
4549 		}
4550 		free(*base_commit_id);
4551 		if (*fileindex) {
4552 			got_fileindex_free(*fileindex);
4553 			*fileindex = NULL;
4554 		}
4555 		lock_worktree(worktree, LOCK_SH);
4556 	}
4557 	return err;
4558 }
4559 
4560 const struct got_error *
4561 got_worktree_histedit_postpone(struct got_worktree *worktree,
4562     struct got_fileindex *fileindex)
4563 {
4564 	if (fileindex)
4565 		got_fileindex_free(fileindex);
4566 	return lock_worktree(worktree, LOCK_SH);
4567 }
4568 
4569 const struct got_error *
4570 got_worktree_histedit_in_progress(int *in_progress,
4571     struct got_worktree *worktree)
4572 {
4573 	const struct got_error *err;
4574 	char *tmp_branch_name = NULL;
4575 
4576 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4577 	if (err)
4578 		return err;
4579 
4580 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
4581 	free(tmp_branch_name);
4582 	return NULL;
4583 }
4584 
4585 const struct got_error *
4586 got_worktree_histedit_continue(struct got_object_id **commit_id,
4587     struct got_reference **tmp_branch, struct got_reference **branch_ref,
4588     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
4589     struct got_worktree *worktree, struct got_repository *repo)
4590 {
4591 	const struct got_error *err;
4592 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
4593 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
4594 	struct got_reference *commit_ref = NULL;
4595 	struct got_reference *base_commit_ref = NULL;
4596 	char *fileindex_path = NULL;
4597 
4598 	*commit_id = NULL;
4599 	*tmp_branch = NULL;
4600 	*base_commit_id = NULL;
4601 	*fileindex = NULL;
4602 
4603 	err = lock_worktree(worktree, LOCK_EX);
4604 	if (err)
4605 		return err;
4606 
4607 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4608 	if (err)
4609 		goto done;
4610 
4611 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4612 	if (err)
4613 		return err;
4614 
4615 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
4616 	if (err)
4617 		goto done;
4618 
4619 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4620 	if (err)
4621 		goto done;
4622 
4623 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
4624 	    worktree);
4625 	if (err)
4626 		goto done;
4627 
4628 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
4629 	if (err)
4630 		goto done;
4631 
4632 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4633 	if (err)
4634 		goto done;
4635 	err = got_ref_resolve(commit_id, repo, commit_ref);
4636 	if (err)
4637 		goto done;
4638 
4639 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
4640 	if (err)
4641 		goto done;
4642 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
4643 	if (err)
4644 		goto done;
4645 
4646 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
4647 	if (err)
4648 		goto done;
4649 done:
4650 	free(commit_ref_name);
4651 	free(branch_ref_name);
4652 	free(fileindex_path);
4653 	if (commit_ref)
4654 		got_ref_close(commit_ref);
4655 	if (base_commit_ref)
4656 		got_ref_close(base_commit_ref);
4657 	if (err) {
4658 		free(*commit_id);
4659 		*commit_id = NULL;
4660 		free(*base_commit_id);
4661 		*base_commit_id = NULL;
4662 		if (*tmp_branch) {
4663 			got_ref_close(*tmp_branch);
4664 			*tmp_branch = NULL;
4665 		}
4666 		if (*fileindex) {
4667 			got_fileindex_free(*fileindex);
4668 			*fileindex = NULL;
4669 		}
4670 		lock_worktree(worktree, LOCK_EX);
4671 	}
4672 	return err;
4673 }
4674 
4675 static const struct got_error *
4676 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
4677 {
4678 	const struct got_error *err;
4679 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
4680 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
4681 
4682 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4683 	if (err)
4684 		goto done;
4685 	err = delete_ref(tmp_branch_name, repo);
4686 	if (err)
4687 		goto done;
4688 
4689 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
4690 	    worktree);
4691 	if (err)
4692 		goto done;
4693 	err = delete_ref(base_commit_ref_name, repo);
4694 	if (err)
4695 		goto done;
4696 
4697 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
4698 	if (err)
4699 		goto done;
4700 	err = delete_ref(branch_ref_name, repo);
4701 	if (err)
4702 		goto done;
4703 
4704 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4705 	if (err)
4706 		goto done;
4707 	err = delete_ref(commit_ref_name, repo);
4708 	if (err)
4709 		goto done;
4710 done:
4711 	free(tmp_branch_name);
4712 	free(base_commit_ref_name);
4713 	free(branch_ref_name);
4714 	free(commit_ref_name);
4715 	return err;
4716 }
4717 
4718 const struct got_error *
4719 got_worktree_histedit_abort(struct got_worktree *worktree,
4720     struct got_fileindex *fileindex, struct got_repository *repo,
4721     struct got_reference *branch, struct got_object_id *base_commit_id,
4722     got_worktree_checkout_cb progress_cb, void *progress_arg)
4723 {
4724 	const struct got_error *err, *unlockerr, *sync_err;
4725 	struct got_reference *resolved = NULL;
4726 	char *fileindex_path = NULL;
4727 	struct got_pathlist_head revertible_paths;
4728 	struct got_pathlist_entry *pe;
4729 	struct collect_revertible_paths_arg crp_arg;
4730 	struct got_object_id *tree_id = NULL;
4731 
4732 	TAILQ_INIT(&revertible_paths);
4733 
4734 	err = lock_worktree(worktree, LOCK_EX);
4735 	if (err)
4736 		return err;
4737 
4738 	err = got_ref_open(&resolved, repo,
4739 	    got_ref_get_symref_target(branch), 0);
4740 	if (err)
4741 		goto done;
4742 
4743 	err = got_worktree_set_head_ref(worktree, resolved);
4744 	if (err)
4745 		goto done;
4746 
4747 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
4748 	if (err)
4749 		goto done;
4750 
4751 	err = got_object_id_by_path(&tree_id, repo, base_commit_id,
4752 	    worktree->path_prefix);
4753 	if (err)
4754 		goto done;
4755 
4756 	err = delete_histedit_refs(worktree, repo);
4757 	if (err)
4758 		goto done;
4759 
4760 	err = get_fileindex_path(&fileindex_path, worktree);
4761 	if (err)
4762 		goto done;
4763 
4764 	crp_arg.revertible_paths = &revertible_paths;
4765 	crp_arg.worktree = worktree;
4766 	err = worktree_status(worktree, "", fileindex, repo,
4767 	    collect_revertible_paths, &crp_arg, NULL, NULL);
4768 	if (err)
4769 		goto done;
4770 
4771 	TAILQ_FOREACH(pe, &revertible_paths, entry) {
4772 		err = revert_file(worktree, fileindex, pe->path,
4773 		    progress_cb, progress_arg, repo);
4774 		if (err)
4775 			goto sync;
4776 	}
4777 
4778 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
4779 	    repo, progress_cb, progress_arg, NULL, NULL);
4780 sync:
4781 	sync_err = sync_fileindex(fileindex, fileindex_path);
4782 	if (sync_err && err == NULL)
4783 		err = sync_err;
4784 done:
4785 	got_ref_close(resolved);
4786 	free(tree_id);
4787 	free(fileindex_path);
4788 	TAILQ_FOREACH(pe, &revertible_paths, entry)
4789 		free((char *)pe->path);
4790 	got_pathlist_free(&revertible_paths);
4791 
4792 	unlockerr = lock_worktree(worktree, LOCK_SH);
4793 	if (unlockerr && err == NULL)
4794 		err = unlockerr;
4795 	return err;
4796 }
4797 
4798 const struct got_error *
4799 got_worktree_histedit_complete(struct got_worktree *worktree,
4800     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4801     struct got_reference *edited_branch, struct got_repository *repo)
4802 {
4803 	const struct got_error *err, *unlockerr;
4804 	struct got_object_id *new_head_commit_id = NULL;
4805 	struct got_reference *resolved = NULL;
4806 
4807 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
4808 	if (err)
4809 		return err;
4810 
4811 	err = got_ref_open(&resolved, repo,
4812 	    got_ref_get_symref_target(edited_branch), 0);
4813 	if (err)
4814 		goto done;
4815 
4816 	err = got_ref_change_ref(resolved, new_head_commit_id);
4817 	if (err)
4818 		goto done;
4819 
4820 	err = got_ref_write(resolved, repo);
4821 	if (err)
4822 		goto done;
4823 
4824 	err = got_worktree_set_head_ref(worktree, resolved);
4825 	if (err)
4826 		goto done;
4827 
4828 	err = delete_histedit_refs(worktree, repo);
4829 done:
4830 	if (fileindex)
4831 		got_fileindex_free(fileindex);
4832 	free(new_head_commit_id);
4833 	unlockerr = lock_worktree(worktree, LOCK_SH);
4834 	if (unlockerr && err == NULL)
4835 		err = unlockerr;
4836 	return err;
4837 }
4838 
4839 const struct got_error *
4840 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
4841     struct got_object_id *commit_id, struct got_repository *repo)
4842 {
4843 	const struct got_error *err;
4844 	char *commit_ref_name;
4845 
4846 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4847 	if (err)
4848 		return err;
4849 
4850 	err = store_commit_id(commit_ref_name, commit_id, repo);
4851 	if (err)
4852 		goto done;
4853 
4854 	err = delete_ref(commit_ref_name, repo);
4855 done:
4856 	free(commit_ref_name);
4857 	return err;
4858 }
4859 
4860 static const struct got_error *
4861 stage_path(const char *path, size_t path_len, struct got_worktree *worktree,
4862     struct got_fileindex *fileindex, struct got_repository *repo,
4863     got_worktree_status_cb status_cb, void *status_arg)
4864 {
4865 	const struct got_error *err = NULL;
4866 	char *ondisk_path;
4867 	struct got_fileindex_entry *ie;
4868 	unsigned char status;
4869 	struct stat sb;
4870 	struct got_object_id *blob_id = NULL;
4871 	uint32_t stage;
4872 
4873 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
4874 		return got_error_from_errno("asprintf");
4875 
4876 	ie = got_fileindex_entry_get(fileindex, path, path_len);
4877 	if (ie == NULL) {
4878 		err = got_error_path(path, GOT_ERR_FILE_STATUS);
4879 		goto done;
4880 	}
4881 
4882 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
4883 	if (err)
4884 		goto done;
4885 
4886 	switch (status) {
4887 	case GOT_STATUS_ADD:
4888 	case GOT_STATUS_MODIFY:
4889 		err = got_object_blob_create(&blob_id, ondisk_path,
4890 		    repo);
4891 		if (err)
4892 			goto done;
4893 		memcpy(ie->staged_blob_sha1, blob_id->sha1,
4894 		    SHA1_DIGEST_LENGTH);
4895 		if (status == GOT_STATUS_ADD)
4896 			stage = GOT_FILEIDX_STAGE_ADD;
4897 		else
4898 			stage = GOT_FILEIDX_STAGE_MODIFY;
4899 		break;
4900 	case GOT_STATUS_DELETE:
4901 		stage = GOT_FILEIDX_STAGE_DELETE;
4902 		break;
4903 	default:
4904 		err = got_error_path(path, GOT_ERR_FILE_STATUS);
4905 		goto done;
4906 	}
4907 
4908 	got_fileindex_entry_stage_set(ie, stage);
4909 
4910 	/* XXX TODO pass 'staged' status separately */
4911 	err = (*status_cb)(status_arg, status, path, blob_id, NULL);
4912 done:
4913 	free(blob_id);
4914 	free(ondisk_path);
4915 	return err;
4916 }
4917 
4918 const struct got_error *
4919 got_worktree_stage_paths(struct got_worktree *worktree,
4920     struct got_pathlist_head *paths, struct got_repository *repo,
4921     got_worktree_status_cb status_cb, void *status_arg,
4922     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
4923 {
4924 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4925 	struct got_pathlist_entry *pe;
4926 	struct got_fileindex *fileindex = NULL;
4927 	char *fileindex_path = NULL;
4928 
4929 	err = lock_worktree(worktree, LOCK_EX);
4930 	if (err)
4931 		return err;
4932 
4933 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4934 	if (err)
4935 		goto done;
4936 
4937 	TAILQ_FOREACH(pe, paths, entry) {
4938 		if (cancel_cb) {
4939 			err = (*cancel_cb)(cancel_arg);
4940 			if (err)
4941 				break;
4942 		}
4943 		err = stage_path(pe->path, pe->path_len, worktree, fileindex,
4944 		    repo, status_cb, status_arg);
4945 		if (err)
4946 			break;
4947 	}
4948 
4949 	sync_err = sync_fileindex(fileindex, fileindex_path);
4950 	if (sync_err && err == NULL)
4951 		err = sync_err;
4952 done:
4953 	free(fileindex_path);
4954 	if (fileindex)
4955 		got_fileindex_free(fileindex);
4956 	unlockerr = lock_worktree(worktree, LOCK_SH);
4957 	if (unlockerr && err == NULL)
4958 		err = unlockerr;
4959 	return err;
4960 }