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/queue.h>
19 #include <sys/tree.h>
20 
21 #include <dirent.h>
22 #include <limits.h>
23 #include <stddef.h>
24 #include <string.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <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_cancel.h"
43 #include "got_worktree.h"
44 #include "got_opentemp.h"
45 #include "got_diff.h"
46 
47 #include "got_lib_worktree.h"
48 #include "got_lib_sha1.h"
49 #include "got_lib_fileindex.h"
50 #include "got_lib_inflate.h"
51 #include "got_lib_delta.h"
52 #include "got_lib_object.h"
53 #include "got_lib_object_parse.h"
54 #include "got_lib_object_create.h"
55 #include "got_lib_object_idset.h"
56 #include "got_lib_diff.h"
57 
58 #ifndef MIN
59 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
60 #endif
61 
62 static const struct got_error *
63 create_meta_file(const char *path_got, const char *name, const char *content)
64 {
65 	const struct got_error *err = NULL;
66 	char *path;
67 
68 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
69 		return got_error_from_errno("asprintf");
70 
71 	err = got_path_create_file(path, content);
72 	free(path);
73 	return err;
74 }
75 
76 static const struct got_error *
77 update_meta_file(const char *path_got, const char *name, const char *content)
78 {
79 	const struct got_error *err = NULL;
80 	FILE *tmpfile = NULL;
81 	char *tmppath = NULL;
82 	char *path = NULL;
83 
84 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
85 		err = got_error_from_errno("asprintf");
86 		path = NULL;
87 		goto done;
88 	}
89 
90 	err = got_opentemp_named(&tmppath, &tmpfile, path);
91 	if (err)
92 		goto done;
93 
94 	if (content) {
95 		int len = fprintf(tmpfile, "%s\n", content);
96 		if (len != strlen(content) + 1) {
97 			err = got_error_from_errno2("fprintf", tmppath);
98 			goto done;
99 		}
100 	}
101 
102 	if (rename(tmppath, path) != 0) {
103 		err = got_error_from_errno3("rename", tmppath, path);
104 		unlink(tmppath);
105 		goto done;
106 	}
107 
108 done:
109 	if (fclose(tmpfile) != 0 && err == NULL)
110 		err = got_error_from_errno2("fclose", tmppath);
111 	free(tmppath);
112 	return err;
113 }
114 
115 static const struct got_error *
116 read_meta_file(char **content, const char *path_got, const char *name)
117 {
118 	const struct got_error *err = NULL;
119 	char *path;
120 	int fd = -1;
121 	ssize_t n;
122 	struct stat sb;
123 
124 	*content = NULL;
125 
126 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
127 		err = got_error_from_errno("asprintf");
128 		path = NULL;
129 		goto done;
130 	}
131 
132 	fd = open(path, O_RDONLY | O_NOFOLLOW);
133 	if (fd == -1) {
134 		if (errno == ENOENT)
135 			err = got_error_path(path, GOT_ERR_WORKTREE_META);
136 		else
137 			err = got_error_from_errno2("open", path);
138 		goto done;
139 	}
140 	if (flock(fd, LOCK_SH | LOCK_NB) == -1) {
141 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
142 		    : got_error_from_errno2("flock", path));
143 		goto done;
144 	}
145 
146 	if (fstat(fd, &sb) != 0) {
147 		err = got_error_from_errno2("fstat", path);
148 		goto done;
149 	}
150 	*content = calloc(1, sb.st_size);
151 	if (*content == NULL) {
152 		err = got_error_from_errno("calloc");
153 		goto done;
154 	}
155 
156 	n = read(fd, *content, sb.st_size);
157 	if (n != sb.st_size) {
158 		err = (n == -1 ? got_error_from_errno2("read", path) :
159 		    got_error_path(path, GOT_ERR_WORKTREE_META));
160 		goto done;
161 	}
162 	if ((*content)[sb.st_size - 1] != '\n') {
163 		err = got_error_path(path, GOT_ERR_WORKTREE_META);
164 		goto done;
165 	}
166 	(*content)[sb.st_size - 1] = '\0';
167 
168 done:
169 	if (fd != -1 && close(fd) == -1 && err == NULL)
170 		err = got_error_from_errno2("close", path_got);
171 	free(path);
172 	if (err) {
173 		free(*content);
174 		*content = NULL;
175 	}
176 	return err;
177 }
178 
179 static const struct got_error *
180 write_head_ref(const char *path_got, struct got_reference *head_ref)
181 {
182 	const struct got_error *err = NULL;
183 	char *refstr = NULL;
184 
185 	if (got_ref_is_symbolic(head_ref)) {
186 		refstr = got_ref_to_str(head_ref);
187 		if (refstr == NULL)
188 			return got_error_from_errno("got_ref_to_str");
189 	} else {
190 		refstr = strdup(got_ref_get_name(head_ref));
191 		if (refstr == NULL)
192 			return got_error_from_errno("strdup");
193 	}
194 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
195 	free(refstr);
196 	return err;
197 }
198 
199 const struct got_error *
200 got_worktree_init(const char *path, struct got_reference *head_ref,
201     const char *prefix, struct got_repository *repo)
202 {
203 	const struct got_error *err = NULL;
204 	struct got_object_id *commit_id = NULL;
205 	uuid_t uuid;
206 	uint32_t uuid_status;
207 	int obj_type;
208 	char *path_got = NULL;
209 	char *formatstr = NULL;
210 	char *absprefix = NULL;
211 	char *basestr = NULL;
212 	char *uuidstr = NULL;
213 
214 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
215 		err = got_error(GOT_ERR_WORKTREE_REPO);
216 		goto done;
217 	}
218 
219 	err = got_ref_resolve(&commit_id, repo, head_ref);
220 	if (err)
221 		return err;
222 	err = got_object_get_type(&obj_type, repo, commit_id);
223 	if (err)
224 		return err;
225 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
226 		return got_error(GOT_ERR_OBJ_TYPE);
227 
228 	if (!got_path_is_absolute(prefix)) {
229 		if (asprintf(&absprefix, "/%s", prefix) == -1)
230 			return got_error_from_errno("asprintf");
231 	}
232 
233 	/* Create top-level directory (may already exist). */
234 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
235 		err = got_error_from_errno2("mkdir", path);
236 		goto done;
237 	}
238 
239 	/* Create .got directory (may already exist). */
240 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
241 		err = got_error_from_errno("asprintf");
242 		goto done;
243 	}
244 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
245 		err = got_error_from_errno2("mkdir", path_got);
246 		goto done;
247 	}
248 
249 	/* Create an empty lock file. */
250 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
251 	if (err)
252 		goto done;
253 
254 	/* Create an empty file index. */
255 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
256 	if (err)
257 		goto done;
258 
259 	/* Write the HEAD reference. */
260 	err = write_head_ref(path_got, head_ref);
261 	if (err)
262 		goto done;
263 
264 	/* Record our base commit. */
265 	err = got_object_id_str(&basestr, commit_id);
266 	if (err)
267 		goto done;
268 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
269 	if (err)
270 		goto done;
271 
272 	/* Store path to repository. */
273 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
274 	    got_repo_get_path(repo));
275 	if (err)
276 		goto done;
277 
278 	/* Store in-repository path prefix. */
279 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
280 	    absprefix ? absprefix : prefix);
281 	if (err)
282 		goto done;
283 
284 	/* Generate UUID. */
285 	uuid_create(&uuid, &uuid_status);
286 	if (uuid_status != uuid_s_ok) {
287 		err = got_error_uuid(uuid_status);
288 		goto done;
289 	}
290 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
291 	if (uuid_status != uuid_s_ok) {
292 		err = got_error_uuid(uuid_status);
293 		goto done;
294 	}
295 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
296 	if (err)
297 		goto done;
298 
299 	/* Stamp work tree with format file. */
300 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
301 		err = got_error_from_errno("asprintf");
302 		goto done;
303 	}
304 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
305 	if (err)
306 		goto done;
307 
308 done:
309 	free(commit_id);
310 	free(path_got);
311 	free(formatstr);
312 	free(absprefix);
313 	free(basestr);
314 	free(uuidstr);
315 	return err;
316 }
317 
318 static const struct got_error *
319 open_worktree(struct got_worktree **worktree, const char *path)
320 {
321 	const struct got_error *err = NULL;
322 	char *path_got;
323 	char *formatstr = NULL;
324 	char *uuidstr = NULL;
325 	char *path_lock = NULL;
326 	char *base_commit_id_str = NULL;
327 	int version, fd = -1;
328 	const char *errstr;
329 	struct got_repository *repo = NULL;
330 	uint32_t uuid_status;
331 
332 	*worktree = NULL;
333 
334 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
335 		err = got_error_from_errno("asprintf");
336 		path_got = NULL;
337 		goto done;
338 	}
339 
340 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
341 		err = got_error_from_errno("asprintf");
342 		path_lock = NULL;
343 		goto done;
344 	}
345 
346 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
347 	if (fd == -1) {
348 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
349 		    : got_error_from_errno2("open", path_lock));
350 		goto done;
351 	}
352 
353 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
354 	if (err)
355 		goto done;
356 
357 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
358 	if (errstr) {
359 		err = got_error_msg(GOT_ERR_WORKTREE_META,
360 		    "could not parse work tree format version number");
361 		goto done;
362 	}
363 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
364 		err = got_error(GOT_ERR_WORKTREE_VERS);
365 		goto done;
366 	}
367 
368 	*worktree = calloc(1, sizeof(**worktree));
369 	if (*worktree == NULL) {
370 		err = got_error_from_errno("calloc");
371 		goto done;
372 	}
373 	(*worktree)->lockfd = -1;
374 
375 	(*worktree)->root_path = strdup(path);
376 	if ((*worktree)->root_path == NULL) {
377 		err = got_error_from_errno("strdup");
378 		goto done;
379 	}
380 	err = read_meta_file(&(*worktree)->repo_path, path_got,
381 	    GOT_WORKTREE_REPOSITORY);
382 	if (err)
383 		goto done;
384 
385 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
386 	    GOT_WORKTREE_PATH_PREFIX);
387 	if (err)
388 		goto done;
389 
390 	err = read_meta_file(&base_commit_id_str, path_got,
391 	    GOT_WORKTREE_BASE_COMMIT);
392 	if (err)
393 		goto done;
394 
395 	err = read_meta_file(&uuidstr, path_got, GOT_WORKTREE_UUID);
396 	if (err)
397 		goto done;
398 	uuid_from_string(uuidstr, &(*worktree)->uuid, &uuid_status);
399 	if (uuid_status != uuid_s_ok) {
400 		err = got_error_uuid(uuid_status);
401 		goto done;
402 	}
403 
404 	err = got_repo_open(&repo, (*worktree)->repo_path);
405 	if (err)
406 		goto done;
407 
408 	err = got_object_resolve_id_str(&(*worktree)->base_commit_id, repo,
409 	    base_commit_id_str);
410 	if (err)
411 		goto done;
412 
413 	err = read_meta_file(&(*worktree)->head_ref_name, path_got,
414 	    GOT_WORKTREE_HEAD_REF);
415 done:
416 	if (repo)
417 		got_repo_close(repo);
418 	free(path_got);
419 	free(path_lock);
420 	free(base_commit_id_str);
421 	free(uuidstr);
422 	free(formatstr);
423 	if (err) {
424 		if (fd != -1)
425 			close(fd);
426 		if (*worktree != NULL)
427 			got_worktree_close(*worktree);
428 		*worktree = NULL;
429 	} else
430 		(*worktree)->lockfd = fd;
431 
432 	return err;
433 }
434 
435 const struct got_error *
436 got_worktree_open(struct got_worktree **worktree, const char *path)
437 {
438 	const struct got_error *err = NULL;
439 
440 	do {
441 		err = open_worktree(worktree, path);
442 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT))
443 			return err;
444 		if (*worktree)
445 			return NULL;
446 		path = dirname(path);
447 		if (path == NULL)
448 			return got_error_from_errno2("dirname", path);
449 	} while (!((path[0] == '.' || path[0] == '/') && path[1] == '\0'));
450 
451 	return got_error(GOT_ERR_NOT_WORKTREE);
452 }
453 
454 const struct got_error *
455 got_worktree_close(struct got_worktree *worktree)
456 {
457 	const struct got_error *err = NULL;
458 	free(worktree->root_path);
459 	free(worktree->repo_path);
460 	free(worktree->path_prefix);
461 	free(worktree->base_commit_id);
462 	free(worktree->head_ref_name);
463 	if (worktree->lockfd != -1)
464 		if (close(worktree->lockfd) != 0)
465 			err = got_error_from_errno2("close",
466 			    got_worktree_get_root_path(worktree));
467 	free(worktree);
468 	return err;
469 }
470 
471 const char *
472 got_worktree_get_root_path(struct got_worktree *worktree)
473 {
474 	return worktree->root_path;
475 }
476 
477 const char *
478 got_worktree_get_repo_path(struct got_worktree *worktree)
479 {
480 	return worktree->repo_path;
481 }
482 
483 const char *
484 got_worktree_get_path_prefix(struct got_worktree *worktree)
485 {
486 	return worktree->path_prefix;
487 }
488 
489 const struct got_error *
490 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
491     const char *path_prefix)
492 {
493 	char *absprefix = NULL;
494 
495 	if (!got_path_is_absolute(path_prefix)) {
496 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
497 			return got_error_from_errno("asprintf");
498 	}
499 	*match = (strcmp(absprefix ? absprefix : path_prefix,
500 	    worktree->path_prefix) == 0);
501 	free(absprefix);
502 	return NULL;
503 }
504 
505 const char *
506 got_worktree_get_head_ref_name(struct got_worktree *worktree)
507 {
508 	return worktree->head_ref_name;
509 }
510 
511 const struct got_error *
512 got_worktree_set_head_ref(struct got_worktree *worktree,
513     struct got_reference *head_ref)
514 {
515 	const struct got_error *err = NULL;
516 	char *path_got = NULL, *head_ref_name = NULL;
517 
518 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
519 	    GOT_WORKTREE_GOT_DIR) == -1) {
520 		err = got_error_from_errno("asprintf");
521 		path_got = NULL;
522 		goto done;
523 	}
524 
525 	head_ref_name = strdup(got_ref_get_name(head_ref));
526 	if (head_ref_name == NULL) {
527 		err = got_error_from_errno("strdup");
528 		goto done;
529 	}
530 
531 	err = write_head_ref(path_got, head_ref);
532 	if (err)
533 		goto done;
534 
535 	free(worktree->head_ref_name);
536 	worktree->head_ref_name = head_ref_name;
537 done:
538 	free(path_got);
539 	if (err)
540 		free(head_ref_name);
541 	return err;
542 }
543 
544 struct got_object_id *
545 got_worktree_get_base_commit_id(struct got_worktree *worktree)
546 {
547 	return worktree->base_commit_id;
548 }
549 
550 const struct got_error *
551 got_worktree_set_base_commit_id(struct got_worktree *worktree,
552     struct got_repository *repo, struct got_object_id *commit_id)
553 {
554 	const struct got_error *err;
555 	struct got_object *obj = NULL;
556 	char *id_str = NULL;
557 	char *path_got = NULL;
558 
559 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
560 	    GOT_WORKTREE_GOT_DIR) == -1) {
561 		err = got_error_from_errno("asprintf");
562 		path_got = NULL;
563 		goto done;
564 	}
565 
566 	err = got_object_open(&obj, repo, commit_id);
567 	if (err)
568 		return err;
569 
570 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
571 		err = got_error(GOT_ERR_OBJ_TYPE);
572 		goto done;
573 	}
574 
575 	/* Record our base commit. */
576 	err = got_object_id_str(&id_str, commit_id);
577 	if (err)
578 		goto done;
579 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
580 	if (err)
581 		goto done;
582 
583 	free(worktree->base_commit_id);
584 	worktree->base_commit_id = got_object_id_dup(commit_id);
585 	if (worktree->base_commit_id == NULL) {
586 		err = got_error_from_errno("got_object_id_dup");
587 		goto done;
588 	}
589 done:
590 	if (obj)
591 		got_object_close(obj);
592 	free(id_str);
593 	free(path_got);
594 	return err;
595 }
596 
597 static const struct got_error *
598 lock_worktree(struct got_worktree *worktree, int operation)
599 {
600 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
601 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
602 		    : got_error_from_errno2("flock",
603 		    got_worktree_get_root_path(worktree)));
604 	return NULL;
605 }
606 
607 static const struct got_error *
608 add_dir_on_disk(struct got_worktree *worktree, const char *path)
609 {
610 	const struct got_error *err = NULL;
611 	char *abspath;
612 
613 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
614 		return got_error_from_errno("asprintf");
615 
616 	err = got_path_mkdir(abspath);
617 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
618 		struct stat sb;
619 		err = NULL;
620 		if (lstat(abspath, &sb) == -1) {
621 			err = got_error_from_errno2("lstat", abspath);
622 		} else if (!S_ISDIR(sb.st_mode)) {
623 			/* TODO directory is obstructed; do something */
624 			err = got_error(GOT_ERR_FILE_OBSTRUCTED);
625 		}
626 	}
627 	free(abspath);
628 	return err;
629 }
630 
631 static const struct got_error *
632 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
633 {
634 	const struct got_error *err = NULL;
635 	uint8_t fbuf1[8192];
636 	uint8_t fbuf2[8192];
637 	size_t flen1 = 0, flen2 = 0;
638 
639 	*same = 1;
640 
641 	for (;;) {
642 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
643 		if (flen1 == 0 && ferror(f1)) {
644 			err = got_error_from_errno("fread");
645 			break;
646 		}
647 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
648 		if (flen2 == 0 && ferror(f2)) {
649 			err = got_error_from_errno("fread");
650 			break;
651 		}
652 		if (flen1 == 0) {
653 			if (flen2 != 0)
654 				*same = 0;
655 			break;
656 		} else if (flen2 == 0) {
657 			if (flen1 != 0)
658 				*same = 0;
659 			break;
660 		} else if (flen1 == flen2) {
661 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
662 				*same = 0;
663 				break;
664 			}
665 		} else {
666 			*same = 0;
667 			break;
668 		}
669 	}
670 
671 	return err;
672 }
673 
674 static const struct got_error *
675 check_files_equal(int *same, const char *f1_path, const char *f2_path)
676 {
677 	const struct got_error *err = NULL;
678 	struct stat sb;
679 	size_t size1, size2;
680 	FILE *f1 = NULL, *f2 = NULL;
681 
682 	*same = 1;
683 
684 	if (lstat(f1_path, &sb) != 0) {
685 		err = got_error_from_errno2("lstat", f1_path);
686 		goto done;
687 	}
688 	size1 = sb.st_size;
689 
690 	if (lstat(f2_path, &sb) != 0) {
691 		err = got_error_from_errno2("lstat", f2_path);
692 		goto done;
693 	}
694 	size2 = sb.st_size;
695 
696 	if (size1 != size2) {
697 		*same = 0;
698 		return NULL;
699 	}
700 
701 	f1 = fopen(f1_path, "r");
702 	if (f1 == NULL)
703 		return got_error_from_errno2("open", f1_path);
704 
705 	f2 = fopen(f2_path, "r");
706 	if (f2 == NULL) {
707 		err = got_error_from_errno2("open", f2_path);
708 		goto done;
709 	}
710 
711 	err = check_file_contents_equal(same, f1, f2);
712 done:
713 	if (f1 && fclose(f1) != 0 && err == NULL)
714 		err = got_error_from_errno("fclose");
715 	if (f2 && fclose(f2) != 0 && err == NULL)
716 		err = got_error_from_errno("fclose");
717 
718 	return err;
719 }
720 
721 /*
722  * Perform a 3-way merge where blob_orig acts as the common ancestor,
723  * the file at deriv_path acts as the first derived version, and the
724  * file on disk acts as the second derived version.
725  */
726 static const struct got_error *
727 merge_file(int *local_changes_subsumed, struct got_worktree *worktree,
728     struct got_blob_object *blob_orig, const char *ondisk_path,
729     const char *path, uint16_t st_mode, const char *deriv_path,
730     const char *label_deriv, struct got_repository *repo,
731     got_worktree_checkout_cb progress_cb, void *progress_arg)
732 {
733 	const struct got_error *err = NULL;
734 	int merged_fd = -1;
735 	FILE *f_orig = NULL;
736 	char *blob_orig_path = NULL;
737 	char *merged_path = NULL, *base_path = NULL;
738 	int overlapcnt = 0;
739 	char *parent;
740 
741 	*local_changes_subsumed = 0;
742 
743 	parent = dirname(ondisk_path);
744 	if (parent == NULL)
745 		return got_error_from_errno2("dirname", ondisk_path);
746 
747 	if (asprintf(&base_path, "%s/got-merged", parent) == -1)
748 		return got_error_from_errno("asprintf");
749 
750 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
751 	if (err)
752 		goto done;
753 
754 	free(base_path);
755 	if (asprintf(&base_path, "%s/got-merge-blob-orig", parent) == -1) {
756 		err = got_error_from_errno("asprintf");
757 		base_path = NULL;
758 		goto done;
759 	}
760 
761 	err = got_opentemp_named(&blob_orig_path, &f_orig, base_path);
762 	if (err)
763 		goto done;
764 	if (blob_orig) {
765 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
766 		    blob_orig);
767 		if (err)
768 			goto done;
769 	} else {
770 		/*
771 		 * If the file has no blob, this is an "add vs add" conflict,
772 		 * and we simply use an empty ancestor file to make both files
773 		 * appear in the merged result in their entirety.
774 		 */
775 	}
776 
777 	err = got_merge_diff3(&overlapcnt, merged_fd, deriv_path,
778 	    blob_orig_path, ondisk_path, label_deriv, path);
779 	if (err)
780 		goto done;
781 
782 	err = (*progress_cb)(progress_arg,
783 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
784 	if (err)
785 		goto done;
786 
787 	if (fsync(merged_fd) != 0) {
788 		err = got_error_from_errno("fsync");
789 		goto done;
790 	}
791 
792 	/* Check if a clean merge has subsumed all local changes. */
793 	if (overlapcnt == 0) {
794 		err = check_files_equal(local_changes_subsumed, deriv_path,
795 		    merged_path);
796 		if (err)
797 			goto done;
798 	}
799 
800 	if (chmod(merged_path, st_mode) != 0) {
801 		err = got_error_from_errno2("chmod", merged_path);
802 		goto done;
803 	}
804 
805 	if (rename(merged_path, ondisk_path) != 0) {
806 		err = got_error_from_errno3("rename", merged_path,
807 		    ondisk_path);
808 		unlink(merged_path);
809 		goto done;
810 	}
811 
812 done:
813 	if (merged_fd != -1 && close(merged_fd) != 0 && err == NULL)
814 		err = got_error_from_errno("close");
815 	if (f_orig && fclose(f_orig) != 0 && err == NULL)
816 		err = got_error_from_errno("fclose");
817 	free(merged_path);
818 	free(base_path);
819 	if (blob_orig_path) {
820 		unlink(blob_orig_path);
821 		free(blob_orig_path);
822 	}
823 	return err;
824 }
825 
826 /*
827  * Perform a 3-way merge where blob_orig acts as the common ancestor,
828  * blob_deriv acts as the first derived version, and the file on disk
829  * acts as the second derived version.
830  */
831 static const struct got_error *
832 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
833     struct got_blob_object *blob_orig, const char *ondisk_path,
834     const char *path, uint16_t st_mode, struct got_blob_object *blob_deriv,
835     struct got_object_id *deriv_base_commit_id,
836     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
837     void *progress_arg)
838 {
839 	const struct got_error *err = NULL;
840 	FILE *f_deriv = NULL;
841 	char *blob_deriv_path = NULL, *base_path = NULL, *id_str = NULL;
842 	char *label_deriv = NULL, *parent;
843 
844 	*local_changes_subsumed = 0;
845 
846 	parent = dirname(ondisk_path);
847 	if (parent == NULL)
848 		return got_error_from_errno2("dirname", ondisk_path);
849 
850 	free(base_path);
851 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
852 		err = got_error_from_errno("asprintf");
853 		base_path = NULL;
854 		goto done;
855 	}
856 
857 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path);
858 	if (err)
859 		goto done;
860 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
861 	    blob_deriv);
862 	if (err)
863 		goto done;
864 
865 	err = got_object_id_str(&id_str, deriv_base_commit_id);
866 	if (err)
867 		goto done;
868 	if (asprintf(&label_deriv, "commit %s", id_str) == -1) {
869 		err = got_error_from_errno("asprintf");
870 		goto done;
871 	}
872 
873 	err = merge_file(local_changes_subsumed, worktree, blob_orig,
874 	    ondisk_path, path, st_mode, blob_deriv_path, label_deriv,
875 	    repo, progress_cb, progress_arg);
876 done:
877 	if (f_deriv && fclose(f_deriv) != 0 && err == NULL)
878 		err = got_error_from_errno("fclose");
879 	free(base_path);
880 	if (blob_deriv_path) {
881 		unlink(blob_deriv_path);
882 		free(blob_deriv_path);
883 	}
884 	free(id_str);
885 	free(label_deriv);
886 	return err;
887 }
888 
889 static const struct got_error *
890 update_blob_fileindex_entry(struct got_worktree *worktree,
891     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
892     const char *ondisk_path, const char *path, struct got_blob_object *blob,
893     int update_timestamps)
894 {
895 	const struct got_error *err = NULL;
896 
897 	if (ie == NULL)
898 		ie = got_fileindex_entry_get(fileindex, path, strlen(path));
899 	if (ie)
900 		err = got_fileindex_entry_update(ie, ondisk_path,
901 		    blob->id.sha1, worktree->base_commit_id->sha1,
902 		    update_timestamps);
903 	else {
904 		struct got_fileindex_entry *new_ie;
905 		err = got_fileindex_entry_alloc(&new_ie, ondisk_path,
906 		    path, blob->id.sha1, worktree->base_commit_id->sha1);
907 		if (!err)
908 			err = got_fileindex_entry_add(fileindex, new_ie);
909 	}
910 	return err;
911 }
912 
913 static const struct got_error *
914 install_blob(struct got_worktree *worktree, const char *ondisk_path,
915    const char *path, uint16_t te_mode, uint16_t st_mode,
916    struct got_blob_object *blob, int restoring_missing_file,
917    int reverting_versioned_file, struct got_repository *repo,
918    got_worktree_checkout_cb progress_cb, void *progress_arg)
919 {
920 	const struct got_error *err = NULL;
921 	int fd = -1;
922 	size_t len, hdrlen;
923 	int update = 0;
924 	char *tmppath = NULL;
925 
926 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
927 	    GOT_DEFAULT_FILE_MODE);
928 	if (fd == -1) {
929 		if (errno == ENOENT) {
930 			char *parent = dirname(path);
931 			if (parent == NULL)
932 				return got_error_from_errno2("dirname", path);
933 			err = add_dir_on_disk(worktree, parent);
934 			if (err)
935 				return err;
936 			fd = open(ondisk_path,
937 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
938 			    GOT_DEFAULT_FILE_MODE);
939 			if (fd == -1)
940 				return got_error_from_errno2("open",
941 				    ondisk_path);
942 		} else if (errno == EEXIST) {
943 			if (!S_ISREG(st_mode)) {
944 				/* TODO file is obstructed; do something */
945 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
946 				goto done;
947 			} else {
948 				err = got_opentemp_named_fd(&tmppath, &fd,
949 				    ondisk_path);
950 				if (err)
951 					goto done;
952 				update = 1;
953 			}
954 		} else
955 			return got_error_from_errno2("open", ondisk_path);
956 	}
957 
958 	if (restoring_missing_file)
959 		err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING, path);
960 	else if (reverting_versioned_file)
961 		err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT, path);
962 	else
963 		err = (*progress_cb)(progress_arg,
964 		    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
965 	if (err)
966 		goto done;
967 
968 	hdrlen = got_object_blob_get_hdrlen(blob);
969 	do {
970 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
971 		err = got_object_blob_read_block(&len, blob);
972 		if (err)
973 			break;
974 		if (len > 0) {
975 			/* Skip blob object header first time around. */
976 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
977 			if (outlen == -1) {
978 				err = got_error_from_errno("write");
979 				goto done;
980 			} else if (outlen != len - hdrlen) {
981 				err = got_error(GOT_ERR_IO);
982 				goto done;
983 			}
984 			hdrlen = 0;
985 		}
986 	} while (len != 0);
987 
988 	if (fsync(fd) != 0) {
989 		err = got_error_from_errno("fsync");
990 		goto done;
991 	}
992 
993 	if (update) {
994 		if (rename(tmppath, ondisk_path) != 0) {
995 			err = got_error_from_errno3("rename", tmppath,
996 			    ondisk_path);
997 			unlink(tmppath);
998 			goto done;
999 		}
1000 	}
1001 
1002 	if (te_mode & S_IXUSR) {
1003 		if (chmod(ondisk_path, st_mode | S_IXUSR) == -1) {
1004 			err = got_error_from_errno2("chmod", ondisk_path);
1005 			goto done;
1006 		}
1007 	} else {
1008 		if (chmod(ondisk_path, st_mode & ~S_IXUSR) == -1) {
1009 			err = got_error_from_errno2("chmod", ondisk_path);
1010 			goto done;
1011 		}
1012 	}
1013 
1014 done:
1015 	if (fd != -1 && close(fd) != 0 && err == NULL)
1016 		err = got_error_from_errno("close");
1017 	free(tmppath);
1018 	return err;
1019 }
1020 
1021 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
1022 static const struct got_error *
1023 get_modified_file_content_status(unsigned char *status, FILE *f)
1024 {
1025 	const struct got_error *err = NULL;
1026 	const char *markers[3] = {
1027 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
1028 		GOT_DIFF_CONFLICT_MARKER_SEP,
1029 		GOT_DIFF_CONFLICT_MARKER_END
1030 	};
1031 	int i = 0;
1032 	char *line;
1033 	size_t len;
1034 	const char delim[3] = {'\0', '\0', '\0'};
1035 
1036 	while (*status == GOT_STATUS_MODIFY) {
1037 		line = fparseln(f, &len, NULL, delim, 0);
1038 		if (line == NULL) {
1039 			if (feof(f))
1040 				break;
1041 			err = got_ferror(f, GOT_ERR_IO);
1042 			break;
1043 		}
1044 
1045 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1046 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1047 			    == 0)
1048 				*status = GOT_STATUS_CONFLICT;
1049 			else
1050 				i++;
1051 		}
1052 	}
1053 
1054 	return err;
1055 }
1056 
1057 static int
1058 stat_info_differs(struct got_fileindex_entry *ie, struct stat *sb)
1059 {
1060 	return !(ie->ctime_sec == sb->st_ctime &&
1061 	    ie->ctime_nsec == sb->st_ctimensec &&
1062 	    ie->mtime_sec == sb->st_mtime &&
1063 	    ie->mtime_nsec == sb->st_mtimensec &&
1064 	    ie->size == (sb->st_size & 0xffffffff));
1065 }
1066 
1067 static unsigned char
1068 get_staged_status(struct got_fileindex_entry *ie)
1069 {
1070 	switch (got_fileindex_entry_stage_get(ie)) {
1071 	case GOT_FILEIDX_STAGE_ADD:
1072 		return GOT_STATUS_ADD;
1073 	case GOT_FILEIDX_STAGE_DELETE:
1074 		return GOT_STATUS_DELETE;
1075 	case GOT_FILEIDX_STAGE_MODIFY:
1076 		return GOT_STATUS_MODIFY;
1077 	default:
1078 		return GOT_STATUS_NO_CHANGE;
1079 	}
1080 }
1081 
1082 static const struct got_error *
1083 get_file_status(unsigned char *status, struct stat *sb,
1084     struct got_fileindex_entry *ie, const char *abspath,
1085     struct got_repository *repo)
1086 {
1087 	const struct got_error *err = NULL;
1088 	struct got_object_id id;
1089 	size_t hdrlen;
1090 	FILE *f = NULL;
1091 	uint8_t fbuf[8192];
1092 	struct got_blob_object *blob = NULL;
1093 	size_t flen, blen;
1094 	unsigned char staged_status = get_staged_status(ie);
1095 
1096 	*status = GOT_STATUS_NO_CHANGE;
1097 
1098 	if (lstat(abspath, sb) == -1) {
1099 		if (errno == ENOENT) {
1100 			if (got_fileindex_entry_has_file_on_disk(ie))
1101 				*status = GOT_STATUS_MISSING;
1102 			else
1103 				*status = GOT_STATUS_DELETE;
1104 			return NULL;
1105 		}
1106 		return got_error_from_errno2("lstat", abspath);
1107 	}
1108 
1109 	if (!S_ISREG(sb->st_mode)) {
1110 		*status = GOT_STATUS_OBSTRUCTED;
1111 		return NULL;
1112 	}
1113 
1114 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1115 		*status = GOT_STATUS_DELETE;
1116 		return NULL;
1117 	} else if (!got_fileindex_entry_has_blob(ie) &&
1118 	    staged_status != GOT_STATUS_ADD) {
1119 		*status = GOT_STATUS_ADD;
1120 		return NULL;
1121 	}
1122 
1123 	if (!stat_info_differs(ie, sb))
1124 		return NULL;
1125 
1126 	if (staged_status == GOT_STATUS_MODIFY ||
1127 	    staged_status == GOT_STATUS_ADD)
1128 		memcpy(id.sha1, ie->staged_blob_sha1, sizeof(id.sha1));
1129 	else
1130 		memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1131 
1132 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1133 	if (err)
1134 		return err;
1135 
1136 	f = fopen(abspath, "r");
1137 	if (f == NULL) {
1138 		err = got_error_from_errno2("fopen", abspath);
1139 		goto done;
1140 	}
1141 	hdrlen = got_object_blob_get_hdrlen(blob);
1142 	for (;;) {
1143 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1144 		err = got_object_blob_read_block(&blen, blob);
1145 		if (err)
1146 			goto done;
1147 		/* Skip length of blob object header first time around. */
1148 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1149 		if (flen == 0 && ferror(f)) {
1150 			err = got_error_from_errno("fread");
1151 			goto done;
1152 		}
1153 		if (blen == 0) {
1154 			if (flen != 0)
1155 				*status = GOT_STATUS_MODIFY;
1156 			break;
1157 		} else if (flen == 0) {
1158 			if (blen != 0)
1159 				*status = GOT_STATUS_MODIFY;
1160 			break;
1161 		} else if (blen - hdrlen == flen) {
1162 			/* Skip blob object header first time around. */
1163 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1164 				*status = GOT_STATUS_MODIFY;
1165 				break;
1166 			}
1167 		} else {
1168 			*status = GOT_STATUS_MODIFY;
1169 			break;
1170 		}
1171 		hdrlen = 0;
1172 	}
1173 
1174 	if (*status == GOT_STATUS_MODIFY) {
1175 		rewind(f);
1176 		err = get_modified_file_content_status(status, f);
1177 	}
1178 done:
1179 	if (blob)
1180 		got_object_blob_close(blob);
1181 	if (f)
1182 		fclose(f);
1183 	return err;
1184 }
1185 
1186 /*
1187  * Update timestamps in the file index if a file is unmodified and
1188  * we had to run a full content comparison to find out.
1189  */
1190 static const struct got_error *
1191 sync_timestamps(char *ondisk_path, unsigned char status,
1192     struct got_fileindex_entry *ie, struct stat *sb)
1193 {
1194 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1195 		return got_fileindex_entry_update(ie, ondisk_path,
1196 		    ie->blob_sha1, ie->commit_sha1, 1);
1197 
1198 	return NULL;
1199 }
1200 
1201 static const struct got_error *
1202 update_blob(struct got_worktree *worktree,
1203     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1204     struct got_tree_entry *te, const char *path,
1205     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1206     void *progress_arg)
1207 {
1208 	const struct got_error *err = NULL;
1209 	struct got_blob_object *blob = NULL;
1210 	char *ondisk_path;
1211 	unsigned char status = GOT_STATUS_NO_CHANGE;
1212 	struct stat sb;
1213 
1214 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1215 		return got_error_from_errno("asprintf");
1216 
1217 	if (ie) {
1218 		if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE) {
1219 			err = got_error_path(ie->path, GOT_ERR_FILE_STAGED);
1220 			goto done;
1221 		}
1222 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1223 		if (err)
1224 			goto done;
1225 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1226 			sb.st_mode = got_fileindex_perms_to_st(ie);
1227 	} else
1228 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
1229 
1230 	if (status == GOT_STATUS_OBSTRUCTED) {
1231 		err = (*progress_cb)(progress_arg, status, path);
1232 		goto done;
1233 	}
1234 
1235 	if (ie && status != GOT_STATUS_MISSING) {
1236 		if (got_fileindex_entry_has_commit(ie) &&
1237 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1238 		    SHA1_DIGEST_LENGTH) == 0) {
1239 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1240 			if (err)
1241 				goto done;
1242 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1243 			    path);
1244 			goto done;
1245 		}
1246 		if (got_fileindex_entry_has_blob(ie) &&
1247 		    memcmp(ie->blob_sha1, te->id->sha1,
1248 		    SHA1_DIGEST_LENGTH) == 0) {
1249 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1250 			goto done;
1251 		}
1252 	}
1253 
1254 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1255 	if (err)
1256 		goto done;
1257 
1258 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1259 		int update_timestamps;
1260 		struct got_blob_object *blob2 = NULL;
1261 		if (got_fileindex_entry_has_blob(ie)) {
1262 			struct got_object_id id2;
1263 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1264 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
1265 			if (err)
1266 				goto done;
1267 		}
1268 		err = merge_blob(&update_timestamps, worktree, blob2,
1269 		    ondisk_path, path, sb.st_mode, blob,
1270 		    worktree->base_commit_id, repo,
1271 		    progress_cb, progress_arg);
1272 		if (blob2)
1273 			got_object_blob_close(blob2);
1274 		/*
1275 		 * Do not update timestamps of files with local changes.
1276 		 * Otherwise, a future status walk would treat them as
1277 		 * unmodified files again.
1278 		 */
1279 		err = got_fileindex_entry_update(ie, ondisk_path,
1280 		    blob->id.sha1, worktree->base_commit_id->sha1,
1281 		    update_timestamps);
1282 	} else if (status == GOT_STATUS_DELETE) {
1283 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1284 		if (err)
1285 			goto done;
1286 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1287 		    ondisk_path, path, blob, 0);
1288 		if (err)
1289 			goto done;
1290 	} else {
1291 		err = install_blob(worktree, ondisk_path, path, te->mode,
1292 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1293 		    repo, progress_cb, progress_arg);
1294 		if (err)
1295 			goto done;
1296 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1297 		    ondisk_path, path, blob, 1);
1298 		if (err)
1299 			goto done;
1300 	}
1301 	got_object_blob_close(blob);
1302 done:
1303 	free(ondisk_path);
1304 	return err;
1305 }
1306 
1307 static const struct got_error *
1308 remove_ondisk_file(const char *root_path, const char *path)
1309 {
1310 	const struct got_error *err = NULL;
1311 	char *ondisk_path = NULL;
1312 
1313 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1314 		return got_error_from_errno("asprintf");
1315 
1316 	if (unlink(ondisk_path) == -1) {
1317 		if (errno != ENOENT)
1318 			err = got_error_from_errno2("unlink", ondisk_path);
1319 	} else {
1320 		char *parent = dirname(ondisk_path);
1321 		while (parent && strcmp(parent, root_path) != 0) {
1322 			if (rmdir(parent) == -1) {
1323 				if (errno != ENOTEMPTY)
1324 					err = got_error_from_errno2("rmdir",
1325 					    parent);
1326 				break;
1327 			}
1328 			parent = dirname(parent);
1329 		}
1330 	}
1331 	free(ondisk_path);
1332 	return err;
1333 }
1334 
1335 static const struct got_error *
1336 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1337     struct got_fileindex_entry *ie, struct got_repository *repo,
1338     got_worktree_checkout_cb progress_cb, void *progress_arg)
1339 {
1340 	const struct got_error *err = NULL;
1341 	unsigned char status;
1342 	struct stat sb;
1343 	char *ondisk_path;
1344 
1345 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
1346 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
1347 
1348 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1349 	    == -1)
1350 		return got_error_from_errno("asprintf");
1351 
1352 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1353 	if (err)
1354 		return err;
1355 
1356 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1357 	    status == GOT_STATUS_ADD) {
1358 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1359 		if (err)
1360 			return err;
1361 		/*
1362 		 * Preserve the working file and change the deleted blob's
1363 		 * entry into a schedule-add entry.
1364 		 */
1365 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1366 		    0);
1367 		if (err)
1368 			return err;
1369 	} else {
1370 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1371 		if (err)
1372 			return err;
1373 		if (status == GOT_STATUS_NO_CHANGE) {
1374 			err = remove_ondisk_file(worktree->root_path, ie->path);
1375 			if (err)
1376 				return err;
1377 		}
1378 		got_fileindex_entry_remove(fileindex, ie);
1379 	}
1380 
1381 	return err;
1382 }
1383 
1384 struct diff_cb_arg {
1385     struct got_fileindex *fileindex;
1386     struct got_worktree *worktree;
1387     struct got_repository *repo;
1388     got_worktree_checkout_cb progress_cb;
1389     void *progress_arg;
1390     got_cancel_cb cancel_cb;
1391     void *cancel_arg;
1392 };
1393 
1394 static const struct got_error *
1395 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1396     struct got_tree_entry *te, const char *parent_path)
1397 {
1398 	struct diff_cb_arg *a = arg;
1399 
1400 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1401 		return got_error(GOT_ERR_CANCELLED);
1402 
1403 	return update_blob(a->worktree, a->fileindex, ie, te,
1404 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1405 }
1406 
1407 static const struct got_error *
1408 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1409 {
1410 	struct diff_cb_arg *a = arg;
1411 
1412 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1413 		return got_error(GOT_ERR_CANCELLED);
1414 
1415 	return delete_blob(a->worktree, a->fileindex, ie,
1416 	    a->repo, a->progress_cb, a->progress_arg);
1417 }
1418 
1419 static const struct got_error *
1420 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1421 {
1422 	struct diff_cb_arg *a = arg;
1423 	const struct got_error *err;
1424 	char *path;
1425 
1426 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1427 		return got_error(GOT_ERR_CANCELLED);
1428 
1429 	if (asprintf(&path, "%s%s%s", parent_path,
1430 	    parent_path[0] ? "/" : "", te->name)
1431 	    == -1)
1432 		return got_error_from_errno("asprintf");
1433 
1434 	if (S_ISDIR(te->mode))
1435 		err = add_dir_on_disk(a->worktree, path);
1436 	else
1437 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1438 		    a->repo, a->progress_cb, a->progress_arg);
1439 
1440 	free(path);
1441 	return err;
1442 }
1443 
1444 static const struct got_error *
1445 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
1446 {
1447 	const struct got_error *err = NULL;
1448 	char *uuidstr = NULL;
1449 	uint32_t uuid_status;
1450 
1451 	*refname = NULL;
1452 
1453 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1454 	if (uuid_status != uuid_s_ok)
1455 		return got_error_uuid(uuid_status);
1456 
1457 	if (asprintf(refname, "%s-%s", prefix, uuidstr)
1458 	    == -1) {
1459 		err = got_error_from_errno("asprintf");
1460 		*refname = NULL;
1461 	}
1462 	free(uuidstr);
1463 	return err;
1464 }
1465 
1466 const struct got_error *
1467 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1468 {
1469 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
1470 }
1471 
1472 static const struct got_error *
1473 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
1474 {
1475 	return get_ref_name(refname, worktree,
1476 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
1477 }
1478 
1479 static const struct got_error *
1480 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
1481 {
1482 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
1483 }
1484 
1485 static const struct got_error *
1486 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
1487 {
1488 	return get_ref_name(refname, worktree,
1489 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
1490 }
1491 
1492 static const struct got_error *
1493 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
1494 {
1495 	return get_ref_name(refname, worktree,
1496 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
1497 }
1498 
1499 static const struct got_error *
1500 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
1501 {
1502 	return get_ref_name(refname, worktree,
1503 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
1504 }
1505 
1506 static const struct got_error *
1507 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
1508 {
1509 	return get_ref_name(refname, worktree,
1510 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
1511 }
1512 
1513 static const struct got_error *
1514 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
1515 {
1516 	return get_ref_name(refname, worktree,
1517 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
1518 }
1519 
1520 static const struct got_error *
1521 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
1522 {
1523 	return get_ref_name(refname, worktree,
1524 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
1525 }
1526 
1527 const struct got_error *
1528 got_worktree_get_histedit_script_path(char **path,
1529     struct got_worktree *worktree)
1530 {
1531 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
1532 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
1533 		*path = NULL;
1534 		return got_error_from_errno("asprintf");
1535 	}
1536 	return NULL;
1537 }
1538 
1539 /*
1540  * Prevent Git's garbage collector from deleting our base commit by
1541  * setting a reference to our base commit's ID.
1542  */
1543 static const struct got_error *
1544 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1545 {
1546 	const struct got_error *err = NULL;
1547 	struct got_reference *ref = NULL;
1548 	char *refname;
1549 
1550 	err = got_worktree_get_base_ref_name(&refname, worktree);
1551 	if (err)
1552 		return err;
1553 
1554 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1555 	if (err)
1556 		goto done;
1557 
1558 	err = got_ref_write(ref, repo);
1559 done:
1560 	free(refname);
1561 	if (ref)
1562 		got_ref_close(ref);
1563 	return err;
1564 }
1565 
1566 static const struct got_error *
1567 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
1568 {
1569 	const struct got_error *err = NULL;
1570 
1571 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1572 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1573 		err = got_error_from_errno("asprintf");
1574 		*fileindex_path = NULL;
1575 	}
1576 	return err;
1577 }
1578 
1579 
1580 static const struct got_error *
1581 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1582    struct got_worktree *worktree)
1583 {
1584 	const struct got_error *err = NULL;
1585 	FILE *index = NULL;
1586 
1587 	*fileindex_path = NULL;
1588 	*fileindex = got_fileindex_alloc();
1589 	if (*fileindex == NULL)
1590 		return got_error_from_errno("got_fileindex_alloc");
1591 
1592 	err = get_fileindex_path(fileindex_path, worktree);
1593 	if (err)
1594 		goto done;
1595 
1596 	index = fopen(*fileindex_path, "rb");
1597 	if (index == NULL) {
1598 		if (errno != ENOENT)
1599 			err = got_error_from_errno2("fopen", *fileindex_path);
1600 	} else {
1601 		err = got_fileindex_read(*fileindex, index);
1602 		if (fclose(index) != 0 && err == NULL)
1603 			err = got_error_from_errno("fclose");
1604 	}
1605 done:
1606 	if (err) {
1607 		free(*fileindex_path);
1608 		*fileindex_path = NULL;
1609 		got_fileindex_free(*fileindex);
1610 		*fileindex = NULL;
1611 	}
1612 	return err;
1613 }
1614 
1615 struct bump_base_commit_id_arg {
1616 	struct got_object_id *base_commit_id;
1617 	const char *path;
1618 	size_t path_len;
1619 	const char *entry_name;
1620 	got_worktree_checkout_cb progress_cb;
1621 	void *progress_arg;
1622 };
1623 
1624 /* Bump base commit ID of all files within an updated part of the work tree. */
1625 static const struct got_error *
1626 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
1627 {
1628 	const struct got_error *err;
1629 	struct bump_base_commit_id_arg *a = arg;
1630 
1631 	if (a->entry_name) {
1632 		if (strcmp(ie->path, a->path) != 0)
1633 			return NULL;
1634 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
1635 		return NULL;
1636 
1637 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
1638 	    SHA1_DIGEST_LENGTH) == 0)
1639 		return NULL;
1640 
1641 	if (a->progress_cb) {
1642 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
1643 		    ie->path);
1644 		if (err)
1645 			return err;
1646 	}
1647 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
1648 	return NULL;
1649 }
1650 
1651 static const struct got_error *
1652 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
1653 {
1654 	const struct got_error *err = NULL;
1655 	char *new_fileindex_path = NULL;
1656 	FILE *new_index = NULL;
1657 
1658 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1659 	    fileindex_path);
1660 	if (err)
1661 		goto done;
1662 
1663 	err = got_fileindex_write(fileindex, new_index);
1664 	if (err)
1665 		goto done;
1666 
1667 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1668 		err = got_error_from_errno3("rename", new_fileindex_path,
1669 		    fileindex_path);
1670 		unlink(new_fileindex_path);
1671 	}
1672 done:
1673 	if (new_index)
1674 		fclose(new_index);
1675 	free(new_fileindex_path);
1676 	return err;
1677 }
1678 
1679 static const struct got_error *
1680 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
1681     struct got_object_id **tree_id, const char *wt_relpath,
1682     struct got_worktree *worktree, struct got_repository *repo)
1683 {
1684 	const struct got_error *err = NULL;
1685 	struct got_object_id *id = NULL;
1686 	char *in_repo_path = NULL;
1687 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
1688 
1689 	*entry_type = GOT_OBJ_TYPE_ANY;
1690 	*tree_relpath = NULL;
1691 	*tree_id = NULL;
1692 
1693 	if (wt_relpath[0] == '\0') {
1694 		/* Check out all files within the work tree. */
1695 		*entry_type = GOT_OBJ_TYPE_TREE;
1696 		*tree_relpath = strdup("");
1697 		if (*tree_relpath == NULL) {
1698 			err = got_error_from_errno("strdup");
1699 			goto done;
1700 		}
1701 		err = got_object_id_by_path(tree_id, repo,
1702 		    worktree->base_commit_id, worktree->path_prefix);
1703 		if (err)
1704 			goto done;
1705 		return NULL;
1706 	}
1707 
1708 	/* Check out a subset of files in the work tree. */
1709 
1710 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
1711 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
1712 		err = got_error_from_errno("asprintf");
1713 		goto done;
1714 	}
1715 
1716 	err = got_object_id_by_path(&id, repo, worktree->base_commit_id,
1717 	    in_repo_path);
1718 	if (err)
1719 		goto done;
1720 
1721 	free(in_repo_path);
1722 	in_repo_path = NULL;
1723 
1724 	err = got_object_get_type(entry_type, repo, id);
1725 	if (err)
1726 		goto done;
1727 
1728 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
1729 		/* Check out a single file. */
1730 		if (strchr(wt_relpath, '/')  == NULL) {
1731 			/* Check out a single file in work tree's root dir. */
1732 			in_repo_path = strdup(worktree->path_prefix);
1733 			if (in_repo_path == NULL) {
1734 				err = got_error_from_errno("strdup");
1735 				goto done;
1736 			}
1737 			*tree_relpath = strdup("");
1738 			if (*tree_relpath == NULL) {
1739 				err = got_error_from_errno("strdup");
1740 				goto done;
1741 			}
1742 		} else {
1743 			/* Check out a single file in a subdirectory. */
1744 			err = got_path_dirname(tree_relpath, wt_relpath);
1745 			if (err)
1746 				return err;
1747 			if (asprintf(&in_repo_path, "%s%s%s",
1748 			    worktree->path_prefix, is_root_wt ? "" : "/",
1749 			    *tree_relpath) == -1) {
1750 				err = got_error_from_errno("asprintf");
1751 				goto done;
1752 			}
1753 		}
1754 		err = got_object_id_by_path(tree_id, repo,
1755 		    worktree->base_commit_id, in_repo_path);
1756 	} else {
1757 		/* Check out all files within a subdirectory. */
1758 		*tree_id = got_object_id_dup(id);
1759 		if (*tree_id == NULL) {
1760 			err = got_error_from_errno("got_object_id_dup");
1761 			goto done;
1762 		}
1763 		*tree_relpath = strdup(wt_relpath);
1764 		if (*tree_relpath == NULL) {
1765 			err = got_error_from_errno("strdup");
1766 			goto done;
1767 		}
1768 	}
1769 done:
1770 	free(id);
1771 	free(in_repo_path);
1772 	if (err) {
1773 		*entry_type = GOT_OBJ_TYPE_ANY;
1774 		free(*tree_relpath);
1775 		*tree_relpath = NULL;
1776 		free(*tree_id);
1777 		*tree_id = NULL;
1778 	}
1779 	return err;
1780 }
1781 
1782 static const struct got_error *
1783 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
1784     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
1785     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1786     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
1787 {
1788 	const struct got_error *err = NULL;
1789 	struct got_commit_object *commit = NULL;
1790 	struct got_tree_object *tree = NULL;
1791 	struct got_fileindex_diff_tree_cb diff_cb;
1792 	struct diff_cb_arg arg;
1793 
1794 	err = ref_base_commit(worktree, repo);
1795 	if (err)
1796 		goto done;
1797 
1798 	err = got_object_open_as_commit(&commit, repo,
1799 	   worktree->base_commit_id);
1800 	if (err)
1801 		goto done;
1802 
1803 	err = got_object_open_as_tree(&tree, repo, tree_id);
1804 	if (err)
1805 		goto done;
1806 
1807 	if (entry_name &&
1808 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1809 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1810 		goto done;
1811 	}
1812 
1813 	diff_cb.diff_old_new = diff_old_new;
1814 	diff_cb.diff_old = diff_old;
1815 	diff_cb.diff_new = diff_new;
1816 	arg.fileindex = fileindex;
1817 	arg.worktree = worktree;
1818 	arg.repo = repo;
1819 	arg.progress_cb = progress_cb;
1820 	arg.progress_arg = progress_arg;
1821 	arg.cancel_cb = cancel_cb;
1822 	arg.cancel_arg = cancel_arg;
1823 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
1824 	    entry_name, repo, &diff_cb, &arg);
1825 done:
1826 	if (tree)
1827 		got_object_tree_close(tree);
1828 	if (commit)
1829 		got_object_commit_close(commit);
1830 	return err;
1831 }
1832 
1833 const struct got_error *
1834 got_worktree_checkout_files(struct got_worktree *worktree,
1835     struct got_pathlist_head *paths, struct got_repository *repo,
1836     got_worktree_checkout_cb progress_cb, void *progress_arg,
1837     got_cancel_cb cancel_cb, void *cancel_arg)
1838 {
1839 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1840 	struct got_commit_object *commit = NULL;
1841 	struct got_tree_object *tree = NULL;
1842 	struct got_fileindex *fileindex = NULL;
1843 	char *fileindex_path = NULL;
1844 	struct got_pathlist_entry *pe;
1845 	struct tree_path_data {
1846 		SIMPLEQ_ENTRY(tree_path_data) entry;
1847 		struct got_object_id *tree_id;
1848 		int entry_type;
1849 		char *relpath;
1850 		char *entry_name;
1851 	} *tpd = NULL;
1852 	SIMPLEQ_HEAD(tree_paths, tree_path_data) tree_paths;
1853 
1854 	SIMPLEQ_INIT(&tree_paths);
1855 
1856 	err = lock_worktree(worktree, LOCK_EX);
1857 	if (err)
1858 		return err;
1859 
1860 	/* Map all specified paths to in-repository trees. */
1861 	TAILQ_FOREACH(pe, paths, entry) {
1862 		tpd = malloc(sizeof(*tpd));
1863 		if (tpd == NULL) {
1864 			err = got_error_from_errno("malloc");
1865 			goto done;
1866 		}
1867 
1868 		err = find_tree_entry_for_checkout(&tpd->entry_type,
1869 		    &tpd->relpath, &tpd->tree_id, pe->path, worktree, repo);
1870 		if (err) {
1871 			free(tpd);
1872 			goto done;
1873 		}
1874 
1875 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
1876 			err = got_path_basename(&tpd->entry_name, pe->path);
1877 			if (err) {
1878 				free(tpd->relpath);
1879 				free(tpd->tree_id);
1880 				free(tpd);
1881 				goto done;
1882 			}
1883 		} else
1884 			tpd->entry_name = NULL;
1885 
1886 		SIMPLEQ_INSERT_TAIL(&tree_paths, tpd, entry);
1887 	}
1888 
1889 	/*
1890 	 * Read the file index.
1891 	 * Checking out files is supposed to be an idempotent operation.
1892 	 * If the on-disk file index is incomplete we will try to complete it.
1893 	 */
1894 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1895 	if (err)
1896 		goto done;
1897 
1898 	tpd = SIMPLEQ_FIRST(&tree_paths);
1899 	TAILQ_FOREACH(pe, paths, entry) {
1900 		struct bump_base_commit_id_arg bbc_arg;
1901 
1902 		err = checkout_files(worktree, fileindex, tpd->relpath,
1903 		    tpd->tree_id, tpd->entry_name, repo,
1904 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
1905 		if (err)
1906 			break;
1907 
1908 		bbc_arg.base_commit_id = worktree->base_commit_id;
1909 		bbc_arg.entry_name = tpd->entry_name;
1910 		bbc_arg.path = pe->path;
1911 		bbc_arg.path_len = pe->path_len;
1912 		bbc_arg.progress_cb = progress_cb;
1913 		bbc_arg.progress_arg = progress_arg;
1914 		err = got_fileindex_for_each_entry_safe(fileindex,
1915 		    bump_base_commit_id, &bbc_arg);
1916 		if (err)
1917 			break;
1918 
1919 		tpd = SIMPLEQ_NEXT(tpd, entry);
1920 	}
1921 	sync_err = sync_fileindex(fileindex, fileindex_path);
1922 	if (sync_err && err == NULL)
1923 		err = sync_err;
1924 done:
1925 	free(fileindex_path);
1926 	if (tree)
1927 		got_object_tree_close(tree);
1928 	if (commit)
1929 		got_object_commit_close(commit);
1930 	if (fileindex)
1931 		got_fileindex_free(fileindex);
1932 	while (!SIMPLEQ_EMPTY(&tree_paths)) {
1933 		tpd = SIMPLEQ_FIRST(&tree_paths);
1934 		SIMPLEQ_REMOVE_HEAD(&tree_paths, entry);
1935 		free(tpd->relpath);
1936 		free(tpd->tree_id);
1937 		free(tpd);
1938 	}
1939 	unlockerr = lock_worktree(worktree, LOCK_SH);
1940 	if (unlockerr && err == NULL)
1941 		err = unlockerr;
1942 	return err;
1943 }
1944 
1945 struct merge_file_cb_arg {
1946     struct got_worktree *worktree;
1947     struct got_fileindex *fileindex;
1948     got_worktree_checkout_cb progress_cb;
1949     void *progress_arg;
1950     got_cancel_cb cancel_cb;
1951     void *cancel_arg;
1952     struct got_object_id *commit_id2;
1953 };
1954 
1955 static const struct got_error *
1956 merge_file_cb(void *arg, struct got_blob_object *blob1,
1957     struct got_blob_object *blob2, struct got_object_id *id1,
1958     struct got_object_id *id2, const char *path1, const char *path2,
1959     struct got_repository *repo)
1960 {
1961 	static const struct got_error *err = NULL;
1962 	struct merge_file_cb_arg *a = arg;
1963 	struct got_fileindex_entry *ie;
1964 	char *ondisk_path = NULL;
1965 	struct stat sb;
1966 	unsigned char status;
1967 	int local_changes_subsumed;
1968 
1969 	if (blob1 && blob2) {
1970 		ie = got_fileindex_entry_get(a->fileindex, path2,
1971 		    strlen(path2));
1972 		if (ie == NULL)
1973 			return (*a->progress_cb)(a->progress_arg,
1974 			    GOT_STATUS_MISSING, path2);
1975 
1976 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1977 		    path2) == -1)
1978 			return got_error_from_errno("asprintf");
1979 
1980 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1981 		if (err)
1982 			goto done;
1983 
1984 		if (status == GOT_STATUS_DELETE) {
1985 			err = (*a->progress_cb)(a->progress_arg,
1986 			    GOT_STATUS_MERGE, path2);
1987 			goto done;
1988 		}
1989 		if (status != GOT_STATUS_NO_CHANGE &&
1990 		    status != GOT_STATUS_MODIFY &&
1991 		    status != GOT_STATUS_CONFLICT &&
1992 		    status != GOT_STATUS_ADD) {
1993 			err = (*a->progress_cb)(a->progress_arg, status, path2);
1994 			goto done;
1995 		}
1996 
1997 		err = merge_blob(&local_changes_subsumed, a->worktree, blob1,
1998 		    ondisk_path, path2, sb.st_mode, blob2, a->commit_id2, repo,
1999 		    a->progress_cb, a->progress_arg);
2000 	} else if (blob1) {
2001 		ie = got_fileindex_entry_get(a->fileindex, path1,
2002 		    strlen(path1));
2003 		if (ie == NULL)
2004 			return (*a->progress_cb)(a->progress_arg,
2005 			    GOT_STATUS_MISSING, path2);
2006 
2007 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2008 		    path1) == -1)
2009 			return got_error_from_errno("asprintf");
2010 
2011 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2012 		if (err)
2013 			goto done;
2014 
2015 		switch (status) {
2016 		case GOT_STATUS_NO_CHANGE:
2017 			err = (*a->progress_cb)(a->progress_arg,
2018 			    GOT_STATUS_DELETE, path1);
2019 			if (err)
2020 				goto done;
2021 			err = remove_ondisk_file(a->worktree->root_path, path1);
2022 			if (err)
2023 				goto done;
2024 			if (ie)
2025 				got_fileindex_entry_mark_deleted_from_disk(ie);
2026 			break;
2027 		case GOT_STATUS_DELETE:
2028 		case GOT_STATUS_MISSING:
2029 			err = (*a->progress_cb)(a->progress_arg,
2030 			    GOT_STATUS_DELETE, path1);
2031 			if (err)
2032 				goto done;
2033 			if (ie)
2034 				got_fileindex_entry_mark_deleted_from_disk(ie);
2035 			break;
2036 		case GOT_STATUS_ADD:
2037 		case GOT_STATUS_MODIFY:
2038 		case GOT_STATUS_CONFLICT:
2039 			err = (*a->progress_cb)(a->progress_arg,
2040 			    GOT_STATUS_CANNOT_DELETE, path1);
2041 			if (err)
2042 				goto done;
2043 			break;
2044 		case GOT_STATUS_OBSTRUCTED:
2045 			err = (*a->progress_cb)(a->progress_arg, status, path1);
2046 			if (err)
2047 				goto done;
2048 			break;
2049 		default:
2050 			break;
2051 		}
2052 	} else if (blob2) {
2053 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2054 		    path2) == -1)
2055 			return got_error_from_errno("asprintf");
2056 		ie = got_fileindex_entry_get(a->fileindex, path2,
2057 		    strlen(path2));
2058 		if (ie) {
2059 			err = get_file_status(&status, &sb, ie, ondisk_path,
2060 			    repo);
2061 			if (err)
2062 				goto done;
2063 			if (status != GOT_STATUS_NO_CHANGE &&
2064 			    status != GOT_STATUS_MODIFY &&
2065 			    status != GOT_STATUS_CONFLICT &&
2066 			    status != GOT_STATUS_ADD) {
2067 				err = (*a->progress_cb)(a->progress_arg,
2068 				    status, path2);
2069 				goto done;
2070 			}
2071 			err = merge_blob(&local_changes_subsumed, a->worktree,
2072 			    NULL, ondisk_path, path2, sb.st_mode, blob2,
2073 			    a->commit_id2, repo,
2074 			    a->progress_cb, a->progress_arg);
2075 			if (status == GOT_STATUS_DELETE) {
2076 				err = update_blob_fileindex_entry(a->worktree,
2077 				    a->fileindex, ie, ondisk_path, ie->path,
2078 				    blob2, 0);
2079 				if (err)
2080 					goto done;
2081 			}
2082 		} else {
2083 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
2084 			err = install_blob(a->worktree, ondisk_path, path2,
2085 			    /* XXX get this from parent tree! */
2086 			    GOT_DEFAULT_FILE_MODE,
2087 			    sb.st_mode, blob2, 0, 0, repo,
2088 			    a->progress_cb, a->progress_arg);
2089 			if (err)
2090 				goto done;
2091 			err = got_fileindex_entry_alloc(&ie,
2092 			    ondisk_path, path2, NULL, NULL);
2093 			if (err)
2094 				goto done;
2095 			err = got_fileindex_entry_add(a->fileindex, ie);
2096 			if (err) {
2097 				got_fileindex_entry_free(ie);
2098 				goto done;
2099 			}
2100 		}
2101 	}
2102 done:
2103 	free(ondisk_path);
2104 	return err;
2105 }
2106 
2107 struct check_merge_ok_arg {
2108 	struct got_worktree *worktree;
2109 	struct got_repository *repo;
2110 };
2111 
2112 static const struct got_error *
2113 check_merge_ok(void *arg, struct got_fileindex_entry *ie)
2114 {
2115 	const struct got_error *err = NULL;
2116 	struct check_merge_ok_arg *a = arg;
2117 	unsigned char status;
2118 	struct stat sb;
2119 	char *ondisk_path;
2120 
2121 	/* Reject merges into a work tree with mixed base commits. */
2122 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
2123 	    SHA1_DIGEST_LENGTH))
2124 		return got_error(GOT_ERR_MIXED_COMMITS);
2125 
2126 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
2127 	    == -1)
2128 		return got_error_from_errno("asprintf");
2129 
2130 	/* Reject merges into a work tree with conflicted files. */
2131 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
2132 	if (err)
2133 		return err;
2134 	if (status == GOT_STATUS_CONFLICT)
2135 		return got_error(GOT_ERR_CONFLICTS);
2136 
2137 	return NULL;
2138 }
2139 
2140 static const struct got_error *
2141 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2142     const char *fileindex_path, struct got_object_id *commit_id1,
2143     struct got_object_id *commit_id2, struct got_repository *repo,
2144     got_worktree_checkout_cb progress_cb, void *progress_arg,
2145     got_cancel_cb cancel_cb, void *cancel_arg)
2146 {
2147 	const struct got_error *err = NULL, *sync_err;
2148 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
2149 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
2150 	struct merge_file_cb_arg arg;
2151 
2152 	if (commit_id1) {
2153 		err = got_object_id_by_path(&tree_id1, repo, commit_id1,
2154 		    worktree->path_prefix);
2155 		if (err)
2156 			goto done;
2157 
2158 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
2159 		if (err)
2160 			goto done;
2161 	}
2162 
2163 	err = got_object_id_by_path(&tree_id2, repo, commit_id2,
2164 	    worktree->path_prefix);
2165 	if (err)
2166 		goto done;
2167 
2168 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
2169 	if (err)
2170 		goto done;
2171 
2172 	arg.worktree = worktree;
2173 	arg.fileindex = fileindex;
2174 	arg.progress_cb = progress_cb;
2175 	arg.progress_arg = progress_arg;
2176 	arg.cancel_cb = cancel_cb;
2177 	arg.cancel_arg = cancel_arg;
2178 	arg.commit_id2 = commit_id2;
2179 	err = got_diff_tree(tree1, tree2, "", "", repo, merge_file_cb, &arg, 1);
2180 	sync_err = sync_fileindex(fileindex, fileindex_path);
2181 	if (sync_err && err == NULL)
2182 		err = sync_err;
2183 done:
2184 	if (tree1)
2185 		got_object_tree_close(tree1);
2186 	if (tree2)
2187 		got_object_tree_close(tree2);
2188 	return err;
2189 }
2190 
2191 const struct got_error *
2192 got_worktree_merge_files(struct got_worktree *worktree,
2193     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
2194     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2195     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
2196 {
2197 	const struct got_error *err, *unlockerr;
2198 	char *fileindex_path = NULL;
2199 	struct got_fileindex *fileindex = NULL;
2200 	struct check_merge_ok_arg mok_arg;
2201 
2202 	err = lock_worktree(worktree, LOCK_EX);
2203 	if (err)
2204 		return err;
2205 
2206 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2207 	if (err)
2208 		goto done;
2209 
2210 	mok_arg.worktree = worktree;
2211 	mok_arg.repo = repo;
2212 	err = got_fileindex_for_each_entry_safe(fileindex, check_merge_ok,
2213 	    &mok_arg);
2214 	if (err)
2215 		goto done;
2216 
2217 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
2218 	    commit_id2, repo, progress_cb, progress_arg, cancel_cb, cancel_arg);
2219 done:
2220 	if (fileindex)
2221 		got_fileindex_free(fileindex);
2222 	free(fileindex_path);
2223 	unlockerr = lock_worktree(worktree, LOCK_SH);
2224 	if (unlockerr && err == NULL)
2225 		err = unlockerr;
2226 	return err;
2227 }
2228 
2229 struct diff_dir_cb_arg {
2230     struct got_fileindex *fileindex;
2231     struct got_worktree *worktree;
2232     const char *status_path;
2233     size_t status_path_len;
2234     struct got_repository *repo;
2235     got_worktree_status_cb status_cb;
2236     void *status_arg;
2237     got_cancel_cb cancel_cb;
2238     void *cancel_arg;
2239     /* A pathlist containing per-directory pathlists of ignore patterns. */
2240     struct got_pathlist_head ignores;
2241 };
2242 
2243 static const struct got_error *
2244 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
2245     got_worktree_status_cb status_cb, void *status_arg,
2246     struct got_repository *repo)
2247 {
2248 	const struct got_error *err = NULL;
2249 	unsigned char status = GOT_STATUS_NO_CHANGE;
2250 	unsigned char staged_status = get_staged_status(ie);
2251 	struct stat sb;
2252 	struct got_object_id blob_id, commit_id, staged_blob_id;
2253 	struct got_object_id *blob_idp = NULL, *commit_idp = NULL;
2254 	struct got_object_id *staged_blob_idp = NULL;
2255 
2256 	err = get_file_status(&status, &sb, ie, abspath, repo);
2257 	if (err)
2258 		return err;
2259 
2260 	if (status == GOT_STATUS_NO_CHANGE &&
2261 	    staged_status == GOT_STATUS_NO_CHANGE)
2262 		return NULL;
2263 
2264 	if (got_fileindex_entry_has_blob(ie)) {
2265 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2266 		blob_idp = &blob_id;
2267 	}
2268 	if (got_fileindex_entry_has_commit(ie)) {
2269 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2270 		commit_idp = &commit_id;
2271 	}
2272 	if (staged_status == GOT_STATUS_ADD ||
2273 	    staged_status == GOT_STATUS_MODIFY) {
2274 		memcpy(staged_blob_id.sha1, ie->staged_blob_sha1,
2275 		    SHA1_DIGEST_LENGTH);
2276 		staged_blob_idp = &staged_blob_id;
2277 	}
2278 
2279 	return (*status_cb)(status_arg, status, staged_status,
2280 	    ie->path, blob_idp, staged_blob_idp, commit_idp);
2281 }
2282 
2283 static const struct got_error *
2284 status_old_new(void *arg, struct got_fileindex_entry *ie,
2285     struct dirent *de, const char *parent_path)
2286 {
2287 	const struct got_error *err = NULL;
2288 	struct diff_dir_cb_arg *a = arg;
2289 	char *abspath;
2290 
2291 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2292 		return got_error(GOT_ERR_CANCELLED);
2293 
2294 	if (got_path_cmp(parent_path, a->status_path,
2295 	    strlen(parent_path), a->status_path_len) != 0 &&
2296 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
2297 		return NULL;
2298 
2299 	if (parent_path[0]) {
2300 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
2301 		    parent_path, de->d_name) == -1)
2302 			return got_error_from_errno("asprintf");
2303 	} else {
2304 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
2305 		    de->d_name) == -1)
2306 			return got_error_from_errno("asprintf");
2307 	}
2308 
2309 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
2310 	    a->repo);
2311 	free(abspath);
2312 	return err;
2313 }
2314 
2315 static const struct got_error *
2316 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2317 {
2318 	struct diff_dir_cb_arg *a = arg;
2319 	struct got_object_id blob_id, commit_id;
2320 	unsigned char status;
2321 
2322 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2323 		return got_error(GOT_ERR_CANCELLED);
2324 
2325 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
2326 		return NULL;
2327 
2328 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2329 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2330 	if (got_fileindex_entry_has_file_on_disk(ie))
2331 		status = GOT_STATUS_MISSING;
2332 	else
2333 		status = GOT_STATUS_DELETE;
2334 	return (*a->status_cb)(a->status_arg, status, get_staged_status(ie),
2335 	    ie->path, &blob_id, NULL, &commit_id);
2336 }
2337 
2338 void
2339 free_ignorelist(struct got_pathlist_head *ignorelist)
2340 {
2341 	struct got_pathlist_entry *pe;
2342 
2343 	TAILQ_FOREACH(pe, ignorelist, entry)
2344 		free((char *)pe->path);
2345 	got_pathlist_free(ignorelist);
2346 }
2347 
2348 void
2349 free_ignores(struct got_pathlist_head *ignores)
2350 {
2351 	struct got_pathlist_entry *pe;
2352 
2353 	TAILQ_FOREACH(pe, ignores, entry) {
2354 		struct got_pathlist_head *ignorelist = pe->data;
2355 		free_ignorelist(ignorelist);
2356 		free((char *)pe->path);
2357 	}
2358 	got_pathlist_free(ignores);
2359 }
2360 
2361 static const struct got_error *
2362 read_ignores(struct got_pathlist_head *ignores, const char *path, FILE *f)
2363 {
2364 	const struct got_error *err = NULL;
2365 	struct got_pathlist_entry *pe = NULL;
2366 	struct got_pathlist_head *ignorelist;
2367 	char *line = NULL, *pattern, *dirpath = NULL;
2368 	size_t linesize = 0;
2369 	ssize_t linelen;
2370 
2371 	ignorelist = calloc(1, sizeof(*ignorelist));
2372 	if (ignorelist == NULL)
2373 		return got_error_from_errno("calloc");
2374 	TAILQ_INIT(ignorelist);
2375 
2376 	while ((linelen = getline(&line, &linesize, f)) != -1) {
2377 		if (linelen > 0 && line[linelen - 1] == '\n')
2378 			line[linelen - 1] = '\0';
2379 		if (asprintf(&pattern, "%s%s%s", path, path[0] ? "/" : "",
2380 		    line) == -1) {
2381 			err = got_error_from_errno("asprintf");
2382 			goto done;
2383 		}
2384 		err = got_pathlist_insert(NULL, ignorelist, pattern, NULL);
2385 		if (err)
2386 			goto done;
2387 	}
2388 	if (ferror(f)) {
2389 		err = got_error_from_errno("getline");
2390 		goto done;
2391 	}
2392 
2393 	dirpath = strdup(path);
2394 	if (dirpath == NULL) {
2395 		err = got_error_from_errno("strdup");
2396 		goto done;
2397 	}
2398 	err = got_pathlist_insert(&pe, ignores, dirpath, ignorelist);
2399 done:
2400 	free(line);
2401 	if (err || pe == NULL) {
2402 		free(dirpath);
2403 		free_ignorelist(ignorelist);
2404 	}
2405 	return err;
2406 }
2407 
2408 int
2409 match_ignores(struct got_pathlist_head *ignores, const char *path)
2410 {
2411 	struct got_pathlist_entry *pe;
2412 
2413 	/*
2414 	 * The ignores pathlist contains ignore lists from children before
2415 	 * parents, so we can find the most specific ignorelist by walking
2416 	 * ignores backwards.
2417 	 */
2418 	pe = TAILQ_LAST(ignores, got_pathlist_head);
2419 	while (pe) {
2420 		if (got_path_is_child(path, pe->path, pe->path_len)) {
2421 			struct got_pathlist_head *ignorelist = pe->data;
2422 			struct got_pathlist_entry *pi;
2423 			TAILQ_FOREACH(pi, ignorelist, entry) {
2424 				if (fnmatch(pi->path, path,
2425 				    FNM_PATHNAME | FNM_LEADING_DIR))
2426 					continue;
2427 				return 1;
2428 			}
2429 		}
2430 		pe = TAILQ_PREV(pe, got_pathlist_head, entry);
2431 	}
2432 
2433 	return 0;
2434 }
2435 
2436 static const struct got_error *
2437 add_ignores(struct got_pathlist_head *ignores, const char *root_path,
2438     const char *path)
2439 {
2440 	const struct got_error *err = NULL;
2441 	char *ignorespath;
2442 	FILE *ignoresfile = NULL;
2443 
2444 	/* TODO: read .gitignores as well... */
2445 	if (asprintf(&ignorespath, "%s/%s%s.cvsignore", root_path, path,
2446 	    path[0] ? "/" : "") == -1)
2447 		return got_error_from_errno("asprintf");
2448 
2449 	ignoresfile = fopen(ignorespath, "r");
2450 	if (ignoresfile == NULL) {
2451 		if (errno != ENOENT)
2452 			err = got_error_from_errno2("fopen",
2453 			    ignorespath);
2454 	} else
2455 		err = read_ignores(ignores, path, ignoresfile);
2456 
2457 	if (ignoresfile && fclose(ignoresfile) == EOF && err == NULL)
2458 		err = got_error_from_errno2("flose", path);
2459 	free(ignorespath);
2460 	return err;
2461 }
2462 
2463 static const struct got_error *
2464 status_new(void *arg, struct dirent *de, const char *parent_path)
2465 {
2466 	const struct got_error *err = NULL;
2467 	struct diff_dir_cb_arg *a = arg;
2468 	char *path = NULL;
2469 
2470 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2471 		return got_error(GOT_ERR_CANCELLED);
2472 
2473 	/* XXX ignore symlinks for now */
2474 	if (de->d_type == DT_LNK)
2475 		return NULL;
2476 
2477 	if (parent_path[0]) {
2478 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
2479 			return got_error_from_errno("asprintf");
2480 	} else {
2481 		path = de->d_name;
2482 	}
2483 
2484 	if (de->d_type == DT_DIR)
2485 		err = add_ignores(&a->ignores, a->worktree->root_path, path);
2486 	else if (got_path_is_child(path, a->status_path, a->status_path_len)
2487 	    && !match_ignores(&a->ignores, path))
2488 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
2489 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL);
2490 	if (parent_path[0])
2491 		free(path);
2492 	return err;
2493 }
2494 
2495 static const struct got_error *
2496 report_single_file_status(const char *path, const char *ondisk_path,
2497 struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
2498 void *status_arg, struct got_repository *repo)
2499 {
2500 	struct got_fileindex_entry *ie;
2501 	struct stat sb;
2502 
2503 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
2504 	if (ie)
2505 		return report_file_status(ie, ondisk_path, status_cb,
2506 		    status_arg, repo);
2507 
2508 	if (lstat(ondisk_path, &sb) == -1) {
2509 		if (errno != ENOENT)
2510 			return got_error_from_errno2("lstat", ondisk_path);
2511 		return NULL;
2512 	}
2513 
2514 	if (S_ISREG(sb.st_mode))
2515 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED,
2516 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL);
2517 
2518 	return NULL;
2519 }
2520 
2521 static const struct got_error *
2522 worktree_status(struct got_worktree *worktree, const char *path,
2523     struct got_fileindex *fileindex, struct got_repository *repo,
2524     got_worktree_status_cb status_cb, void *status_arg,
2525     got_cancel_cb cancel_cb, void *cancel_arg)
2526 {
2527 	const struct got_error *err = NULL;
2528 	DIR *workdir = NULL;
2529 	struct got_fileindex_diff_dir_cb fdiff_cb;
2530 	struct diff_dir_cb_arg arg;
2531 	char *ondisk_path = NULL;
2532 
2533 	if (asprintf(&ondisk_path, "%s%s%s",
2534 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
2535 		return got_error_from_errno("asprintf");
2536 
2537 	workdir = opendir(ondisk_path);
2538 	if (workdir == NULL) {
2539 		if (errno != ENOTDIR && errno != ENOENT)
2540 			err = got_error_from_errno2("opendir", ondisk_path);
2541 		else
2542 			err = report_single_file_status(path, ondisk_path,
2543 			    fileindex, status_cb, status_arg, repo);
2544 	} else {
2545 		fdiff_cb.diff_old_new = status_old_new;
2546 		fdiff_cb.diff_old = status_old;
2547 		fdiff_cb.diff_new = status_new;
2548 		arg.fileindex = fileindex;
2549 		arg.worktree = worktree;
2550 		arg.status_path = path;
2551 		arg.status_path_len = strlen(path);
2552 		arg.repo = repo;
2553 		arg.status_cb = status_cb;
2554 		arg.status_arg = status_arg;
2555 		arg.cancel_cb = cancel_cb;
2556 		arg.cancel_arg = cancel_arg;
2557 		TAILQ_INIT(&arg.ignores);
2558 		err = add_ignores(&arg.ignores, worktree->root_path, path);
2559 		if (err == NULL)
2560 			err = got_fileindex_diff_dir(fileindex, workdir,
2561 			    worktree->root_path, path, repo, &fdiff_cb, &arg);
2562 		free_ignores(&arg.ignores);
2563 	}
2564 
2565 	if (workdir)
2566 		closedir(workdir);
2567 	free(ondisk_path);
2568 	return err;
2569 }
2570 
2571 const struct got_error *
2572 got_worktree_status(struct got_worktree *worktree,
2573     struct got_pathlist_head *paths, struct got_repository *repo,
2574     got_worktree_status_cb status_cb, void *status_arg,
2575     got_cancel_cb cancel_cb, void *cancel_arg)
2576 {
2577 	const struct got_error *err = NULL;
2578 	char *fileindex_path = NULL;
2579 	struct got_fileindex *fileindex = NULL;
2580 	struct got_pathlist_entry *pe;
2581 
2582 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2583 	if (err)
2584 		return err;
2585 
2586 	TAILQ_FOREACH(pe, paths, entry) {
2587 		err = worktree_status(worktree, pe->path, fileindex, repo,
2588 			status_cb, status_arg, cancel_cb, cancel_arg);
2589 		if (err)
2590 			break;
2591 	}
2592 	free(fileindex_path);
2593 	got_fileindex_free(fileindex);
2594 	return err;
2595 }
2596 
2597 const struct got_error *
2598 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
2599     const char *arg)
2600 {
2601 	const struct got_error *err = NULL;
2602 	char *resolved, *cwd = NULL, *path = NULL;
2603 	size_t len;
2604 
2605 	*wt_path = NULL;
2606 
2607 	resolved = realpath(arg, NULL);
2608 	if (resolved == NULL) {
2609 		if (errno != ENOENT)
2610 			return got_error_from_errno2("realpath", arg);
2611 		cwd = getcwd(NULL, 0);
2612 		if (cwd == NULL)
2613 			return got_error_from_errno("getcwd");
2614 		if (asprintf(&resolved, "%s/%s", cwd, arg) == -1) {
2615 			err = got_error_from_errno("asprintf");
2616 			goto done;
2617 		}
2618 	}
2619 
2620 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
2621 	    strlen(got_worktree_get_root_path(worktree)))) {
2622 		err = got_error(GOT_ERR_BAD_PATH);
2623 		goto done;
2624 	}
2625 
2626 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
2627 		err = got_path_skip_common_ancestor(&path,
2628 		    got_worktree_get_root_path(worktree), resolved);
2629 		if (err)
2630 			goto done;
2631 	} else {
2632 		path = strdup("");
2633 		if (path == NULL) {
2634 			err = got_error_from_errno("strdup");
2635 			goto done;
2636 		}
2637 	}
2638 
2639 	/* XXX status walk can't deal with trailing slash! */
2640 	len = strlen(path);
2641 	while (len > 0 && path[len - 1] == '/') {
2642 		path[len - 1] = '\0';
2643 		len--;
2644 	}
2645 done:
2646 	free(resolved);
2647 	free(cwd);
2648 	if (err == NULL)
2649 		*wt_path = path;
2650 	else
2651 		free(path);
2652 	return err;
2653 }
2654 
2655 static const struct got_error *
2656 schedule_addition(const char *ondisk_path, struct got_fileindex *fileindex,
2657     const char *relpath, got_worktree_status_cb status_cb, void *status_arg,
2658     struct got_repository *repo)
2659 {
2660 	const struct got_error *err = NULL;
2661 	struct got_fileindex_entry *ie;
2662 	unsigned char status;
2663 	struct stat sb;
2664 
2665 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2666 	if (ie) {
2667 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2668 		if (err)
2669 			return err;
2670 		/* Re-adding an existing entry is a no-op. */
2671 		if (status == GOT_STATUS_ADD)
2672 			return NULL;
2673 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
2674 	}
2675 
2676 	err = got_fileindex_entry_alloc(&ie, ondisk_path, relpath, NULL, NULL);
2677 	if (err)
2678 		return err;
2679 
2680 	err = got_fileindex_entry_add(fileindex, ie);
2681 	if (err) {
2682 		got_fileindex_entry_free(ie);
2683 		return err;
2684 	}
2685 
2686 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2687 }
2688 
2689 const struct got_error *
2690 got_worktree_schedule_add(struct got_worktree *worktree,
2691     struct got_pathlist_head *paths,
2692     got_worktree_status_cb status_cb, void *status_arg,
2693     struct got_repository *repo)
2694 {
2695 	struct got_fileindex *fileindex = NULL;
2696 	char *fileindex_path = NULL;
2697 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2698 	struct got_pathlist_entry *pe;
2699 
2700 	err = lock_worktree(worktree, LOCK_EX);
2701 	if (err)
2702 		return err;
2703 
2704 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2705 	if (err)
2706 		goto done;
2707 
2708 	TAILQ_FOREACH(pe, paths, entry) {
2709 		char *ondisk_path;
2710 		if (asprintf(&ondisk_path, "%s/%s", worktree->root_path,
2711 		    pe->path) == -1)
2712 			return got_error_from_errno("asprintf");
2713 		err = schedule_addition(ondisk_path, fileindex, pe->path,
2714 		    status_cb, status_arg, repo);
2715 		free(ondisk_path);
2716 		if (err)
2717 			break;
2718 	}
2719 	sync_err = sync_fileindex(fileindex, fileindex_path);
2720 	if (sync_err && err == NULL)
2721 		err = sync_err;
2722 done:
2723 	free(fileindex_path);
2724 	if (fileindex)
2725 		got_fileindex_free(fileindex);
2726 	unlockerr = lock_worktree(worktree, LOCK_SH);
2727 	if (unlockerr && err == NULL)
2728 		err = unlockerr;
2729 	return err;
2730 }
2731 
2732 static const struct got_error *
2733 schedule_for_deletion(const char *ondisk_path, struct got_fileindex *fileindex,
2734     const char *relpath, int delete_local_mods,
2735     got_worktree_status_cb status_cb, void *status_arg,
2736     struct got_repository *repo)
2737 {
2738 	const struct got_error *err = NULL;
2739 	struct got_fileindex_entry *ie = NULL;
2740 	unsigned char status, staged_status;
2741 	struct stat sb;
2742 
2743 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2744 	if (ie == NULL)
2745 		return got_error(GOT_ERR_BAD_PATH);
2746 
2747 	staged_status = get_staged_status(ie);
2748 	if (staged_status != GOT_STATUS_NO_CHANGE) {
2749 		if (staged_status == GOT_STATUS_DELETE)
2750 			return NULL;
2751 		return got_error_path(relpath, GOT_ERR_FILE_STAGED);
2752 	}
2753 
2754 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2755 	if (err)
2756 		return err;
2757 
2758 	if (status != GOT_STATUS_NO_CHANGE) {
2759 		if (status == GOT_STATUS_DELETE)
2760 			return NULL;
2761 		if (status == GOT_STATUS_MODIFY && !delete_local_mods)
2762 			return got_error_path(relpath, GOT_ERR_FILE_MODIFIED);
2763 		if (status != GOT_STATUS_MODIFY &&
2764 		    status != GOT_STATUS_MISSING)
2765 			return got_error_path(relpath, GOT_ERR_FILE_STATUS);
2766 	}
2767 
2768 	if (status != GOT_STATUS_MISSING && unlink(ondisk_path) != 0)
2769 		return got_error_from_errno2("unlink", ondisk_path);
2770 
2771 	got_fileindex_entry_mark_deleted_from_disk(ie);
2772 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2773 }
2774 
2775 const struct got_error *
2776 got_worktree_schedule_delete(struct got_worktree *worktree,
2777     struct got_pathlist_head *paths, int delete_local_mods,
2778     got_worktree_status_cb status_cb, void *status_arg,
2779     struct got_repository *repo)
2780 {
2781 	struct got_fileindex *fileindex = NULL;
2782 	char *fileindex_path = NULL;
2783 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2784 	struct got_pathlist_entry *pe;
2785 
2786 	err = lock_worktree(worktree, LOCK_EX);
2787 	if (err)
2788 		return err;
2789 
2790 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2791 	if (err)
2792 		goto done;
2793 
2794 	TAILQ_FOREACH(pe, paths, entry) {
2795 		char *ondisk_path;
2796 		if (asprintf(&ondisk_path, "%s/%s", worktree->root_path,
2797 		    pe->path) == -1)
2798 			return got_error_from_errno("asprintf");
2799 		err = schedule_for_deletion(ondisk_path, fileindex, pe->path,
2800 		    delete_local_mods, status_cb, status_arg, repo);
2801 		free(ondisk_path);
2802 		if (err)
2803 			break;
2804 	}
2805 	sync_err = sync_fileindex(fileindex, fileindex_path);
2806 	if (sync_err && err == NULL)
2807 		err = sync_err;
2808 done:
2809 	free(fileindex_path);
2810 	if (fileindex)
2811 		got_fileindex_free(fileindex);
2812 	unlockerr = lock_worktree(worktree, LOCK_SH);
2813 	if (unlockerr && err == NULL)
2814 		err = unlockerr;
2815 	return err;
2816 }
2817 
2818 static const struct got_error *
2819 copy_one_line(FILE *infile, FILE *outfile, FILE *rejectfile)
2820 {
2821 	const struct got_error *err = NULL;
2822 	char *line = NULL;
2823 	size_t linesize = 0, n;
2824 	ssize_t linelen;
2825 
2826 	linelen = getline(&line, &linesize, infile);
2827 	if (linelen == -1) {
2828 		if (ferror(infile)) {
2829 			err = got_error_from_errno("getline");
2830 			goto done;
2831 		}
2832 		return NULL;
2833 	}
2834 	if (outfile) {
2835 		n = fwrite(line, 1, linelen, outfile);
2836 		if (n != linelen) {
2837 			err = got_ferror(outfile, GOT_ERR_IO);
2838 			goto done;
2839 		}
2840 	}
2841 	if (rejectfile) {
2842 		n = fwrite(line, 1, linelen, rejectfile);
2843 		if (n != linelen)
2844 			err = got_ferror(outfile, GOT_ERR_IO);
2845 	}
2846 done:
2847 	free(line);
2848 	return err;
2849 }
2850 
2851 static const struct got_error *
2852 skip_one_line(FILE *f)
2853 {
2854 	char *line = NULL;
2855 	size_t linesize = 0;
2856 	ssize_t linelen;
2857 
2858 	linelen = getline(&line, &linesize, f);
2859 	free(line);
2860 	if (linelen == -1 && ferror(f))
2861 		return got_error_from_errno("getline");
2862 	return NULL;
2863 }
2864 
2865 static const struct got_error *
2866 copy_change(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
2867     int start_old, int end_old, int start_new, int end_new,
2868     FILE *outfile, FILE *rejectfile)
2869  {
2870 	const struct got_error *err;
2871 
2872 	/* Copy old file's lines leading up to patch. */
2873 	while (!feof(f1) && *line_cur1 < start_old) {
2874 		err = copy_one_line(f1, outfile, NULL);
2875 		if (err)
2876 			return err;
2877 		(*line_cur1)++;
2878 	}
2879 	/* Skip new file's lines leading up to patch. */
2880 	while (!feof(f2) && *line_cur2 < start_new) {
2881 		if (rejectfile)
2882 			err = copy_one_line(f2, NULL, rejectfile);
2883 		else
2884 			err = skip_one_line(f2);
2885 		if (err)
2886 			return err;
2887 		(*line_cur2)++;
2888 	}
2889 	/* Copy patched lines. */
2890 	while (!feof(f2) && *line_cur2 <= end_new) {
2891 		err = copy_one_line(f2, outfile, NULL);
2892 		if (err)
2893 			return err;
2894 		(*line_cur2)++;
2895 	}
2896 	/* Skip over old file's replaced lines. */
2897 	while (!feof(f1) && *line_cur1 <= end_old) {
2898 		if (rejectfile)
2899 			err = copy_one_line(f1, NULL, rejectfile);
2900 		else
2901 			err = skip_one_line(f1);
2902 		if (err)
2903 			return err;
2904 		(*line_cur1)++;
2905 	}
2906 
2907 	return NULL;
2908 }
2909 
2910 static const struct got_error *
2911 copy_remaining_content(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
2912     FILE *outfile, FILE *rejectfile)
2913 {
2914 	const struct got_error *err;
2915 
2916 	if (outfile) {
2917 		/* Copy old file's lines until EOF. */
2918 		while (!feof(f1)) {
2919 			err = copy_one_line(f1, outfile, NULL);
2920 			if (err)
2921 				return err;
2922 			(*line_cur1)++;
2923 		}
2924 	}
2925 	if (rejectfile) {
2926 		/* Copy new file's lines until EOF. */
2927 		while (!feof(f2)) {
2928 			err = copy_one_line(f2, NULL, rejectfile);
2929 			if (err)
2930 				return err;
2931 			(*line_cur2)++;
2932 		}
2933 	}
2934 
2935 	return NULL;
2936 }
2937 
2938 static const struct got_error *
2939 apply_or_reject_change(int *choice, struct got_diff_change *change, int n,
2940     int nchanges, struct got_diff_state *ds, struct got_diff_args *args,
2941     int diff_flags, const char *relpath, FILE *f1, FILE *f2, int *line_cur1,
2942     int *line_cur2, FILE *outfile, FILE *rejectfile,
2943     got_worktree_patch_cb patch_cb, void *patch_arg)
2944 {
2945 	const struct got_error *err = NULL;
2946 	int start_old = change->cv.a;
2947 	int end_old = change->cv.b;
2948 	int start_new = change->cv.c;
2949 	int end_new = change->cv.d;
2950 	long pos1, pos2;
2951 	FILE *hunkfile;
2952 
2953 	*choice = GOT_PATCH_CHOICE_NONE;
2954 
2955 	hunkfile = got_opentemp();
2956 	if (hunkfile == NULL)
2957 		return got_error_from_errno("got_opentemp");
2958 
2959 	pos1 = ftell(f1);
2960 	pos2 = ftell(f2);
2961 
2962 	/* XXX TODO needs error checking */
2963 	got_diff_dump_change(hunkfile, change, ds, args, f1, f2, diff_flags);
2964 
2965 	if (fseek(f1, pos1, SEEK_SET) == -1) {
2966 		err = got_ferror(f1, GOT_ERR_IO);
2967 		goto done;
2968 	}
2969 	if (fseek(f2, pos2, SEEK_SET) == -1) {
2970 		err = got_ferror(f1, GOT_ERR_IO);
2971 		goto done;
2972 	}
2973 	if (fseek(hunkfile, 0L, SEEK_SET) == -1) {
2974 		err = got_ferror(hunkfile, GOT_ERR_IO);
2975 		goto done;
2976 	}
2977 
2978 	err = (*patch_cb)(choice, patch_arg, GOT_STATUS_MODIFY, relpath,
2979 	    hunkfile, n, nchanges);
2980 	if (err)
2981 		goto done;
2982 
2983 	switch (*choice) {
2984 	case GOT_PATCH_CHOICE_YES:
2985 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
2986 		    end_old, start_new, end_new, outfile, rejectfile);
2987 		break;
2988 	case GOT_PATCH_CHOICE_NO:
2989 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
2990 		    end_old, start_new, end_new, rejectfile, outfile);
2991 		break;
2992 	case GOT_PATCH_CHOICE_QUIT:
2993 		break;
2994 	default:
2995 		err = got_error(GOT_ERR_PATCH_CHOICE);
2996 		break;
2997 	}
2998 done:
2999 	if (hunkfile && fclose(hunkfile) == EOF && err == NULL)
3000 		err = got_error_from_errno("fclose");
3001 	return err;
3002 }
3003 
3004 struct revert_file_args {
3005 	struct got_worktree *worktree;
3006 	struct got_fileindex *fileindex;
3007 	got_worktree_checkout_cb progress_cb;
3008 	void *progress_arg;
3009 	got_worktree_patch_cb patch_cb;
3010 	void *patch_arg;
3011 	struct got_repository *repo;
3012 };
3013 
3014 static const struct got_error *
3015 create_patched_content(char **path_outfile, int reverse_patch,
3016     struct got_object_id *blob_id, const char *path2,
3017     const char *relpath, struct got_repository *repo,
3018     got_worktree_patch_cb patch_cb, void *patch_arg)
3019 {
3020 	const struct got_error *err;
3021 	struct got_blob_object *blob = NULL;
3022 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL;
3023 	char *path1 = NULL, *id_str = NULL;
3024 	struct stat sb1, sb2;
3025 	struct got_diff_changes *changes = NULL;
3026 	struct got_diff_state *ds = NULL;
3027 	struct got_diff_args *args = NULL;
3028 	struct got_diff_change *change;
3029 	int diff_flags = 0, line_cur1 = 1, line_cur2 = 1, have_content = 0;
3030 	int n = 0;
3031 
3032 	*path_outfile = NULL;
3033 
3034 	err = got_object_id_str(&id_str, blob_id);
3035 	if (err)
3036 		return err;
3037 
3038 	f2 = fopen(path2, "r");
3039 	if (f2 == NULL) {
3040 		err = got_error_from_errno2("fopen", path2);
3041 		goto done;
3042 	}
3043 
3044 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192);
3045 	if (err)
3046 		goto done;
3047 
3048 	err = got_opentemp_named(&path1, &f1, "got-patched-blob");
3049 	if (err)
3050 		goto done;
3051 
3052 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
3053 	if (err)
3054 		goto done;
3055 
3056 	if (stat(path1, &sb1) == -1) {
3057 		err = got_error_from_errno2("stat", path1);
3058 		goto done;
3059 	}
3060 	if (stat(path2, &sb2) == -1) {
3061 		err = got_error_from_errno2("stat", path2);
3062 		goto done;
3063 	}
3064 
3065 	err = got_diff_files(&changes, &ds, &args, &diff_flags,
3066 	    f1, sb1.st_size, id_str, f2, sb2.st_size, path2, 3, NULL);
3067 	if (err)
3068 		goto done;
3069 
3070 	err = got_opentemp_named(path_outfile, &outfile, "got-patched-content");
3071 	if (err)
3072 		goto done;
3073 
3074 	if (fseek(f1, 0L, SEEK_SET) == -1)
3075 		return got_ferror(f1, GOT_ERR_IO);
3076 	if (fseek(f2, 0L, SEEK_SET) == -1)
3077 		return got_ferror(f2, GOT_ERR_IO);
3078 	SIMPLEQ_FOREACH(change, &changes->entries, entry) {
3079 		int choice;
3080 		err = apply_or_reject_change(&choice, change, ++n,
3081 		    changes->nchanges, ds, args, diff_flags, relpath,
3082 		    f1, f2, &line_cur1, &line_cur2,
3083 		    reverse_patch ? NULL : outfile,
3084 		    reverse_patch ? outfile : NULL,
3085 		    patch_cb, patch_arg);
3086 		if (err)
3087 			goto done;
3088 		if (choice == GOT_PATCH_CHOICE_YES)
3089 			have_content = 1;
3090 		else if (choice == GOT_PATCH_CHOICE_QUIT)
3091 			break;
3092 	}
3093 	if (have_content)
3094 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
3095 		    reverse_patch ? NULL : outfile,
3096 		    reverse_patch ? outfile : NULL);
3097 done:
3098 	free(id_str);
3099 	if (blob)
3100 		got_object_blob_close(blob);
3101 	if (f1 && fclose(f1) == EOF && err == NULL)
3102 		err = got_error_from_errno2("fclose", path1);
3103 	if (f2 && fclose(f2) == EOF && err == NULL)
3104 		err = got_error_from_errno2("fclose", path2);
3105 	if (outfile && fclose(outfile) == EOF && err == NULL)
3106 		err = got_error_from_errno2("fclose", *path_outfile);
3107 	if (path1 && unlink(path1) == -1 && err == NULL)
3108 		err = got_error_from_errno2("unlink", path1);
3109 	if (err || !have_content) {
3110 		if (*path_outfile && unlink(*path_outfile) == -1 && err == NULL)
3111 			err = got_error_from_errno2("unlink", *path_outfile);
3112 		free(*path_outfile);
3113 		*path_outfile = NULL;
3114 	}
3115 	free(args);
3116 	if (ds) {
3117 		got_diff_state_free(ds);
3118 		free(ds);
3119 	}
3120 	if (changes)
3121 		got_diff_free_changes(changes);
3122 	free(path1);
3123 	return err;
3124 }
3125 
3126 static const struct got_error *
3127 revert_file(void *arg, unsigned char status, unsigned char staged_status,
3128     const char *relpath, struct got_object_id *blob_id,
3129     struct got_object_id *staged_blob_id, struct got_object_id *commit_id)
3130 {
3131 	struct revert_file_args *a = arg;
3132 	const struct got_error *err = NULL;
3133 	char *parent_path = NULL;
3134 	struct got_fileindex_entry *ie;
3135 	struct got_tree_object *tree = NULL;
3136 	struct got_object_id *tree_id = NULL;
3137 	const struct got_tree_entry *te = NULL;
3138 	char *tree_path = NULL, *te_name;
3139 	char *ondisk_path = NULL, *path_content = NULL;
3140 	struct got_blob_object *blob = NULL;
3141 
3142 	/* Reverting a staged deletion is a no-op. */
3143 	if (status == GOT_STATUS_DELETE &&
3144 	    staged_status != GOT_STATUS_NO_CHANGE)
3145 		return NULL;
3146 
3147 	if (status == GOT_STATUS_UNVERSIONED)
3148 		return (*a->progress_cb)(a->progress_arg,
3149 		    GOT_STATUS_UNVERSIONED, relpath);
3150 
3151 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
3152 	if (ie == NULL)
3153 		return got_error(GOT_ERR_BAD_PATH);
3154 
3155 	/* Construct in-repository path of tree which contains this blob. */
3156 	err = got_path_dirname(&parent_path, ie->path);
3157 	if (err) {
3158 		if (err->code != GOT_ERR_BAD_PATH)
3159 			goto done;
3160 		parent_path = strdup("/");
3161 		if (parent_path == NULL) {
3162 			err = got_error_from_errno("strdup");
3163 			goto done;
3164 		}
3165 	}
3166 	if (got_path_is_root_dir(a->worktree->path_prefix)) {
3167 		tree_path = strdup(parent_path);
3168 		if (tree_path == NULL) {
3169 			err = got_error_from_errno("strdup");
3170 			goto done;
3171 		}
3172 	} else {
3173 		if (got_path_is_root_dir(parent_path)) {
3174 			tree_path = strdup(a->worktree->path_prefix);
3175 			if (tree_path == NULL) {
3176 				err = got_error_from_errno("strdup");
3177 				goto done;
3178 			}
3179 		} else {
3180 			if (asprintf(&tree_path, "%s/%s",
3181 			    a->worktree->path_prefix, parent_path) == -1) {
3182 				err = got_error_from_errno("asprintf");
3183 				goto done;
3184 			}
3185 		}
3186 	}
3187 
3188 	err = got_object_id_by_path(&tree_id, a->repo,
3189 	    a->worktree->base_commit_id, tree_path);
3190 	if (err) {
3191 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
3192 		    (status == GOT_STATUS_ADD ||
3193 		    staged_status == GOT_STATUS_ADD)))
3194 			goto done;
3195 	} else {
3196 		err = got_object_open_as_tree(&tree, a->repo, tree_id);
3197 		if (err)
3198 			goto done;
3199 
3200 		te_name = basename(ie->path);
3201 		if (te_name == NULL) {
3202 			err = got_error_from_errno2("basename", ie->path);
3203 			goto done;
3204 		}
3205 
3206 		te = got_object_tree_find_entry(tree, te_name);
3207 		if (te == NULL && status != GOT_STATUS_ADD &&
3208 		    staged_status != GOT_STATUS_ADD) {
3209 			err = got_error(GOT_ERR_NO_TREE_ENTRY);
3210 			goto done;
3211 		}
3212 	}
3213 
3214 	switch (status) {
3215 	case GOT_STATUS_ADD:
3216 		if (a->patch_cb) {
3217 			int choice = GOT_PATCH_CHOICE_NONE;
3218 			err = (*a->patch_cb)(&choice, a->patch_arg,
3219 			    status, ie->path, NULL, 1, 1);
3220 			if (err)
3221 				goto done;
3222 			if (choice != GOT_PATCH_CHOICE_YES)
3223 				break;
3224 		}
3225 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_REVERT,
3226 		    ie->path);
3227 		if (err)
3228 			goto done;
3229 		got_fileindex_entry_remove(a->fileindex, ie);
3230 		break;
3231 	case GOT_STATUS_DELETE:
3232 		if (a->patch_cb) {
3233 			int choice = GOT_PATCH_CHOICE_NONE;
3234 			err = (*a->patch_cb)(&choice, a->patch_arg,
3235 			    status, ie->path, NULL, 1, 1);
3236 			if (err)
3237 				goto done;
3238 			if (choice != GOT_PATCH_CHOICE_YES)
3239 				break;
3240 		}
3241 		/* fall through */
3242 	case GOT_STATUS_MODIFY:
3243 	case GOT_STATUS_CONFLICT:
3244 	case GOT_STATUS_MISSING: {
3245 		struct got_object_id id;
3246 		if (staged_status == GOT_STATUS_ADD ||
3247 		    staged_status == GOT_STATUS_MODIFY) {
3248 			memcpy(id.sha1, ie->staged_blob_sha1,
3249 			    SHA1_DIGEST_LENGTH);
3250 		} else
3251 			memcpy(id.sha1, ie->blob_sha1,
3252 			    SHA1_DIGEST_LENGTH);
3253 		err = got_object_open_as_blob(&blob, a->repo, &id, 8192);
3254 		if (err)
3255 			goto done;
3256 
3257 		if (asprintf(&ondisk_path, "%s/%s",
3258 		    got_worktree_get_root_path(a->worktree), relpath) == -1) {
3259 			err = got_error_from_errno("asprintf");
3260 			goto done;
3261 		}
3262 
3263 		if (a->patch_cb && (status == GOT_STATUS_MODIFY ||
3264 		    status == GOT_STATUS_CONFLICT)) {
3265 			err = create_patched_content(&path_content, 1, &id,
3266 			    ondisk_path, ie->path, a->repo,
3267 			    a->patch_cb, a->patch_arg);
3268 			if (err || path_content == NULL)
3269 				break;
3270 			if (rename(path_content, ondisk_path) == -1) {
3271 				err = got_error_from_errno3("rename",
3272 				    path_content, ondisk_path);
3273 				goto done;
3274 			}
3275 		} else {
3276 			err = install_blob(a->worktree, ondisk_path, ie->path,
3277 			    te ? te->mode : GOT_DEFAULT_FILE_MODE,
3278 			    got_fileindex_perms_to_st(ie), blob, 0, 1,
3279 			    a->repo, a->progress_cb, a->progress_arg);
3280 			if (err)
3281 				goto done;
3282 			if (status == GOT_STATUS_DELETE) {
3283 				err = update_blob_fileindex_entry(a->worktree,
3284 				    a->fileindex, ie, ondisk_path, ie->path,
3285 				    blob, 1);
3286 				if (err)
3287 					goto done;
3288 			}
3289 		}
3290 		break;
3291 	}
3292 	default:
3293 		break;
3294 	}
3295 done:
3296 	free(ondisk_path);
3297 	free(path_content);
3298 	free(parent_path);
3299 	free(tree_path);
3300 	if (blob)
3301 		got_object_blob_close(blob);
3302 	if (tree)
3303 		got_object_tree_close(tree);
3304 	free(tree_id);
3305 	return err;
3306 }
3307 
3308 const struct got_error *
3309 got_worktree_revert(struct got_worktree *worktree,
3310     struct got_pathlist_head *paths,
3311     got_worktree_checkout_cb progress_cb, void *progress_arg,
3312     got_worktree_patch_cb patch_cb, void *patch_arg,
3313     struct got_repository *repo)
3314 {
3315 	struct got_fileindex *fileindex = NULL;
3316 	char *fileindex_path = NULL;
3317 	const struct got_error *err = NULL, *unlockerr = NULL;
3318 	const struct got_error *sync_err = NULL;
3319 	struct got_pathlist_entry *pe;
3320 	struct revert_file_args rfa;
3321 
3322 	err = lock_worktree(worktree, LOCK_EX);
3323 	if (err)
3324 		return err;
3325 
3326 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3327 	if (err)
3328 		goto done;
3329 
3330 	rfa.worktree = worktree;
3331 	rfa.fileindex = fileindex;
3332 	rfa.progress_cb = progress_cb;
3333 	rfa.progress_arg = progress_arg;
3334 	rfa.patch_cb = patch_cb;
3335 	rfa.patch_arg = patch_arg;
3336 	rfa.repo = repo;
3337 	TAILQ_FOREACH(pe, paths, entry) {
3338 		err = worktree_status(worktree, pe->path, fileindex, repo,
3339 		    revert_file, &rfa, NULL, NULL);
3340 		if (err)
3341 			break;
3342 	}
3343 	sync_err = sync_fileindex(fileindex, fileindex_path);
3344 	if (sync_err && err == NULL)
3345 		err = sync_err;
3346 done:
3347 	free(fileindex_path);
3348 	if (fileindex)
3349 		got_fileindex_free(fileindex);
3350 	unlockerr = lock_worktree(worktree, LOCK_SH);
3351 	if (unlockerr && err == NULL)
3352 		err = unlockerr;
3353 	return err;
3354 }
3355 
3356 static void
3357 free_commitable(struct got_commitable *ct)
3358 {
3359 	free(ct->path);
3360 	free(ct->in_repo_path);
3361 	free(ct->ondisk_path);
3362 	free(ct->blob_id);
3363 	free(ct->base_blob_id);
3364 	free(ct->staged_blob_id);
3365 	free(ct->base_commit_id);
3366 	free(ct);
3367 }
3368 
3369 struct collect_commitables_arg {
3370 	struct got_pathlist_head *commitable_paths;
3371 	struct got_repository *repo;
3372 	struct got_worktree *worktree;
3373 	int have_staged_files;
3374 };
3375 
3376 static const struct got_error *
3377 collect_commitables(void *arg, unsigned char status,
3378     unsigned char staged_status, const char *relpath,
3379     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
3380     struct got_object_id *commit_id)
3381 {
3382 	struct collect_commitables_arg *a = arg;
3383 	const struct got_error *err = NULL;
3384 	struct got_commitable *ct = NULL;
3385 	struct got_pathlist_entry *new = NULL;
3386 	char *parent_path = NULL, *path = NULL;
3387 	struct stat sb;
3388 
3389 	if (a->have_staged_files) {
3390 		if (staged_status != GOT_STATUS_MODIFY &&
3391 		    staged_status != GOT_STATUS_ADD &&
3392 		    staged_status != GOT_STATUS_DELETE)
3393 			return NULL;
3394 	} else {
3395 		if (status == GOT_STATUS_CONFLICT)
3396 			return got_error(GOT_ERR_COMMIT_CONFLICT);
3397 
3398 		if (status != GOT_STATUS_MODIFY &&
3399 		    status != GOT_STATUS_ADD &&
3400 		    status != GOT_STATUS_DELETE)
3401 			return NULL;
3402 	}
3403 
3404 	if (asprintf(&path, "/%s", relpath) == -1) {
3405 		err = got_error_from_errno("asprintf");
3406 		goto done;
3407 	}
3408 	if (strcmp(path, "/") == 0) {
3409 		parent_path = strdup("");
3410 		if (parent_path == NULL)
3411 			return got_error_from_errno("strdup");
3412 	} else {
3413 		err = got_path_dirname(&parent_path, path);
3414 		if (err)
3415 			return err;
3416 	}
3417 
3418 	ct = calloc(1, sizeof(*ct));
3419 	if (ct == NULL) {
3420 		err = got_error_from_errno("calloc");
3421 		goto done;
3422 	}
3423 
3424 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
3425 	    relpath) == -1) {
3426 		err = got_error_from_errno("asprintf");
3427 		goto done;
3428 	}
3429 	if (status == GOT_STATUS_DELETE || staged_status == GOT_STATUS_DELETE) {
3430 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
3431 	} else {
3432 		if (lstat(ct->ondisk_path, &sb) != 0) {
3433 			err = got_error_from_errno2("lstat", ct->ondisk_path);
3434 			goto done;
3435 		}
3436 		ct->mode = sb.st_mode;
3437 	}
3438 
3439 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
3440 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
3441 	    relpath) == -1) {
3442 		err = got_error_from_errno("asprintf");
3443 		goto done;
3444 	}
3445 
3446 	ct->status = status;
3447 	ct->staged_status = staged_status;
3448 	ct->blob_id = NULL; /* will be filled in when blob gets created */
3449 	if (ct->status != GOT_STATUS_ADD &&
3450 	    ct->staged_status != GOT_STATUS_ADD) {
3451 		ct->base_blob_id = got_object_id_dup(blob_id);
3452 		if (ct->base_blob_id == NULL) {
3453 			err = got_error_from_errno("got_object_id_dup");
3454 			goto done;
3455 		}
3456 		ct->base_commit_id = got_object_id_dup(commit_id);
3457 		if (ct->base_commit_id == NULL) {
3458 			err = got_error_from_errno("got_object_id_dup");
3459 			goto done;
3460 		}
3461 	}
3462 	if (ct->staged_status == GOT_STATUS_ADD ||
3463 	    ct->staged_status == GOT_STATUS_MODIFY) {
3464 		ct->staged_blob_id = got_object_id_dup(staged_blob_id);
3465 		if (ct->staged_blob_id == NULL) {
3466 			err = got_error_from_errno("got_object_id_dup");
3467 			goto done;
3468 		}
3469 	}
3470 	ct->path = strdup(path);
3471 	if (ct->path == NULL) {
3472 		err = got_error_from_errno("strdup");
3473 		goto done;
3474 	}
3475 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
3476 done:
3477 	if (ct && (err || new == NULL))
3478 		free_commitable(ct);
3479 	free(parent_path);
3480 	free(path);
3481 	return err;
3482 }
3483 
3484 static const struct got_error *write_tree(struct got_object_id **,
3485     struct got_tree_object *, const char *, struct got_pathlist_head *,
3486     got_worktree_status_cb status_cb, void *status_arg,
3487     struct got_repository *);
3488 
3489 static const struct got_error *
3490 write_subtree(struct got_object_id **new_subtree_id,
3491     struct got_tree_entry *te, const char *parent_path,
3492     struct got_pathlist_head *commitable_paths,
3493     got_worktree_status_cb status_cb, void *status_arg,
3494     struct got_repository *repo)
3495 {
3496 	const struct got_error *err = NULL;
3497 	struct got_tree_object *subtree;
3498 	char *subpath;
3499 
3500 	if (asprintf(&subpath, "%s%s%s", parent_path,
3501 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
3502 		return got_error_from_errno("asprintf");
3503 
3504 	err = got_object_open_as_tree(&subtree, repo, te->id);
3505 	if (err)
3506 		return err;
3507 
3508 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
3509 	    status_cb, status_arg, repo);
3510 	got_object_tree_close(subtree);
3511 	free(subpath);
3512 	return err;
3513 }
3514 
3515 static const struct got_error *
3516 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
3517 {
3518 	const struct got_error *err = NULL;
3519 	char *ct_parent_path = NULL;
3520 
3521 	*match = 0;
3522 
3523 	if (strchr(ct->in_repo_path, '/') == NULL) {
3524 		*match = got_path_is_root_dir(path);
3525 		return NULL;
3526 	}
3527 
3528 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
3529 	if (err)
3530 		return err;
3531 	*match = (strcmp(path, ct_parent_path) == 0);
3532 	free(ct_parent_path);
3533 	return err;
3534 }
3535 
3536 static mode_t
3537 get_ct_file_mode(struct got_commitable *ct)
3538 {
3539 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
3540 }
3541 
3542 static const struct got_error *
3543 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
3544     struct got_tree_entry *te, struct got_commitable *ct)
3545 {
3546 	const struct got_error *err = NULL;
3547 
3548 	*new_te = NULL;
3549 
3550 	err = got_object_tree_entry_dup(new_te, te);
3551 	if (err)
3552 		goto done;
3553 
3554 	(*new_te)->mode = get_ct_file_mode(ct);
3555 
3556 	free((*new_te)->id);
3557 	if (ct->staged_status == GOT_STATUS_MODIFY)
3558 		(*new_te)->id = got_object_id_dup(ct->staged_blob_id);
3559 	else
3560 		(*new_te)->id = got_object_id_dup(ct->blob_id);
3561 	if ((*new_te)->id == NULL) {
3562 		err = got_error_from_errno("got_object_id_dup");
3563 		goto done;
3564 	}
3565 done:
3566 	if (err && *new_te) {
3567 		got_object_tree_entry_close(*new_te);
3568 		*new_te = NULL;
3569 	}
3570 	return err;
3571 }
3572 
3573 static const struct got_error *
3574 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
3575     struct got_commitable *ct)
3576 {
3577 	const struct got_error *err = NULL;
3578 	char *ct_name;
3579 
3580 	 *new_te = NULL;
3581 
3582 	*new_te = calloc(1, sizeof(**new_te));
3583 	if (*new_te == NULL)
3584 		return got_error_from_errno("calloc");
3585 
3586 	ct_name = basename(ct->path);
3587 	if (ct_name == NULL) {
3588 		err = got_error_from_errno2("basename", ct->path);
3589 		goto done;
3590 	}
3591 	(*new_te)->name = strdup(ct_name);
3592 	if ((*new_te)->name == NULL) {
3593 		err = got_error_from_errno("strdup");
3594 		goto done;
3595 	}
3596 
3597 	(*new_te)->mode = get_ct_file_mode(ct);
3598 
3599 	if (ct->staged_status == GOT_STATUS_ADD)
3600 		(*new_te)->id = got_object_id_dup(ct->staged_blob_id);
3601 	else
3602 		(*new_te)->id = got_object_id_dup(ct->blob_id);
3603 	if ((*new_te)->id == NULL) {
3604 		err = got_error_from_errno("got_object_id_dup");
3605 		goto done;
3606 	}
3607 done:
3608 	if (err && *new_te) {
3609 		got_object_tree_entry_close(*new_te);
3610 		*new_te = NULL;
3611 	}
3612 	return err;
3613 }
3614 
3615 static const struct got_error *
3616 insert_tree_entry(struct got_tree_entry *new_te,
3617     struct got_pathlist_head *paths)
3618 {
3619 	const struct got_error *err = NULL;
3620 	struct got_pathlist_entry *new_pe;
3621 
3622 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
3623 	if (err)
3624 		return err;
3625 	if (new_pe == NULL)
3626 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
3627 	return NULL;
3628 }
3629 
3630 static const struct got_error *
3631 report_ct_status(struct got_commitable *ct,
3632     got_worktree_status_cb status_cb, void *status_arg)
3633 {
3634 	const char *ct_path = ct->path;
3635 	unsigned char status;
3636 
3637 	while (ct_path[0] == '/')
3638 		ct_path++;
3639 
3640 	if (ct->staged_status != GOT_STATUS_NO_CHANGE)
3641 		status = ct->staged_status;
3642 	else
3643 		status = ct->status;
3644 
3645 	return (*status_cb)(status_arg, status, GOT_STATUS_NO_CHANGE,
3646 	    ct_path, ct->blob_id, NULL, NULL);
3647 }
3648 
3649 static const struct got_error *
3650 match_modified_subtree(int *modified, struct got_tree_entry *te,
3651     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
3652 {
3653 	const struct got_error *err = NULL;
3654 	struct got_pathlist_entry *pe;
3655 	char *te_path;
3656 
3657 	*modified = 0;
3658 
3659 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
3660 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
3661 	    te->name) == -1)
3662 		return got_error_from_errno("asprintf");
3663 
3664 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3665 		struct got_commitable *ct = pe->data;
3666 		*modified = got_path_is_child(ct->in_repo_path, te_path,
3667 		    strlen(te_path));
3668 		 if (*modified)
3669 			break;
3670 	}
3671 
3672 	free(te_path);
3673 	return err;
3674 }
3675 
3676 static const struct got_error *
3677 match_deleted_or_modified_ct(struct got_commitable **ctp,
3678     struct got_tree_entry *te, const char *base_tree_path,
3679     struct got_pathlist_head *commitable_paths)
3680 {
3681 	const struct got_error *err = NULL;
3682 	struct got_pathlist_entry *pe;
3683 
3684 	*ctp = NULL;
3685 
3686 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3687 		struct got_commitable *ct = pe->data;
3688 		char *ct_name = NULL;
3689 		int path_matches;
3690 
3691 		if (ct->staged_status == GOT_STATUS_NO_CHANGE) {
3692 			if (ct->status != GOT_STATUS_MODIFY &&
3693 			    ct->status != GOT_STATUS_DELETE)
3694 				continue;
3695 		} else {
3696 			if (ct->staged_status != GOT_STATUS_MODIFY &&
3697 			    ct->staged_status != GOT_STATUS_DELETE)
3698 				continue;
3699 		}
3700 
3701 		if (got_object_id_cmp(ct->base_blob_id, te->id) != 0)
3702 			continue;
3703 
3704 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
3705 		 if (err)
3706 			return err;
3707 		if (!path_matches)
3708 			continue;
3709 
3710 		ct_name = basename(pe->path);
3711 		if (ct_name == NULL)
3712 			return got_error_from_errno2("basename", pe->path);
3713 
3714 		if (strcmp(te->name, ct_name) != 0)
3715 			continue;
3716 
3717 		*ctp = ct;
3718 		break;
3719 	}
3720 
3721 	return err;
3722 }
3723 
3724 static const struct got_error *
3725 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
3726     const char *child_path, const char *path_base_tree,
3727     struct got_pathlist_head *commitable_paths,
3728     got_worktree_status_cb status_cb, void *status_arg,
3729     struct got_repository *repo)
3730 {
3731 	const struct got_error *err = NULL;
3732 	struct got_tree_entry *new_te;
3733 	char *subtree_path;
3734 
3735 	*new_tep = NULL;
3736 
3737 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
3738 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
3739 	    child_path) == -1)
3740 		return got_error_from_errno("asprintf");
3741 
3742 	new_te = calloc(1, sizeof(*new_te));
3743 	new_te->mode = S_IFDIR;
3744 	new_te->name = strdup(child_path);
3745 	if (new_te->name == NULL) {
3746 		err = got_error_from_errno("strdup");
3747 		got_object_tree_entry_close(new_te);
3748 		goto done;
3749 	}
3750 	err = write_tree(&new_te->id, NULL, subtree_path,
3751 	    commitable_paths, status_cb, status_arg, repo);
3752 	if (err) {
3753 		got_object_tree_entry_close(new_te);
3754 		goto done;
3755 	}
3756 done:
3757 	free(subtree_path);
3758 	if (err == NULL)
3759 		*new_tep = new_te;
3760 	return err;
3761 }
3762 
3763 static const struct got_error *
3764 write_tree(struct got_object_id **new_tree_id,
3765     struct got_tree_object *base_tree, const char *path_base_tree,
3766     struct got_pathlist_head *commitable_paths,
3767     got_worktree_status_cb status_cb, void *status_arg,
3768     struct got_repository *repo)
3769 {
3770 	const struct got_error *err = NULL;
3771 	const struct got_tree_entries *base_entries = NULL;
3772 	struct got_pathlist_head paths;
3773 	struct got_tree_entries new_tree_entries;
3774 	struct got_tree_entry *te, *new_te = NULL;
3775 	struct got_pathlist_entry *pe;
3776 
3777 	TAILQ_INIT(&paths);
3778 	new_tree_entries.nentries = 0;
3779 	SIMPLEQ_INIT(&new_tree_entries.head);
3780 
3781 	/* Insert, and recurse into, newly added entries first. */
3782 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3783 		struct got_commitable *ct = pe->data;
3784 		char *child_path = NULL, *slash;
3785 
3786 		if ((ct->status != GOT_STATUS_ADD &&
3787 		    ct->staged_status != GOT_STATUS_ADD) ||
3788 		    (ct->flags & GOT_COMMITABLE_ADDED))
3789 			continue;
3790 
3791 		 if (!got_path_is_child(pe->path, path_base_tree,
3792 		     strlen(path_base_tree)))
3793 			continue;
3794 
3795 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
3796 		    pe->path);
3797 		if (err)
3798 			goto done;
3799 
3800 		slash = strchr(child_path, '/');
3801 		if (slash == NULL) {
3802 			err = alloc_added_blob_tree_entry(&new_te, ct);
3803 			if (err)
3804 				goto done;
3805 			err = report_ct_status(ct, status_cb, status_arg);
3806 			if (err)
3807 				goto done;
3808 			ct->flags |= GOT_COMMITABLE_ADDED;
3809 			err = insert_tree_entry(new_te, &paths);
3810 			if (err)
3811 				goto done;
3812 		} else {
3813 			*slash = '\0'; /* trim trailing path components */
3814 			if (base_tree == NULL ||
3815 			    got_object_tree_find_entry(base_tree, child_path)
3816 			    == NULL) {
3817 				err = make_subtree_for_added_blob(&new_te,
3818 				    child_path, path_base_tree,
3819 				    commitable_paths, status_cb, status_arg,
3820 				    repo);
3821 				if (err)
3822 					goto done;
3823 				err = insert_tree_entry(new_te, &paths);
3824 				if (err)
3825 					goto done;
3826 			}
3827 		}
3828 	}
3829 
3830 	if (base_tree) {
3831 		/* Handle modified and deleted entries. */
3832 		base_entries = got_object_tree_get_entries(base_tree);
3833 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
3834 			struct got_commitable *ct = NULL;
3835 
3836 			if (S_ISDIR(te->mode)) {
3837 				int modified;
3838 				err = got_object_tree_entry_dup(&new_te, te);
3839 				if (err)
3840 					goto done;
3841 				err = match_modified_subtree(&modified, te,
3842 				    path_base_tree, commitable_paths);
3843 				if (err)
3844 					goto done;
3845 				/* Avoid recursion into unmodified subtrees. */
3846 				if (modified) {
3847 					free(new_te->id);
3848 					err = write_subtree(&new_te->id, te,
3849 					    path_base_tree, commitable_paths,
3850 					    status_cb, status_arg, repo);
3851 					if (err)
3852 						goto done;
3853 				}
3854 				err = insert_tree_entry(new_te, &paths);
3855 				if (err)
3856 					goto done;
3857 				continue;
3858 			}
3859 
3860 			err = match_deleted_or_modified_ct(&ct, te,
3861 			    path_base_tree, commitable_paths);
3862 			if (ct) {
3863 				/* NB: Deleted entries get dropped here. */
3864 				if (ct->status == GOT_STATUS_MODIFY ||
3865 				    ct->staged_status == GOT_STATUS_MODIFY) {
3866 					err = alloc_modified_blob_tree_entry(
3867 					    &new_te, te, ct);
3868 					if (err)
3869 						goto done;
3870 					err = insert_tree_entry(new_te, &paths);
3871 					if (err)
3872 						goto done;
3873 				}
3874 				err = report_ct_status(ct, status_cb,
3875 				    status_arg);
3876 				if (err)
3877 					goto done;
3878 			} else {
3879 				/* Entry is unchanged; just copy it. */
3880 				err = got_object_tree_entry_dup(&new_te, te);
3881 				if (err)
3882 					goto done;
3883 				err = insert_tree_entry(new_te, &paths);
3884 				if (err)
3885 					goto done;
3886 			}
3887 		}
3888 	}
3889 
3890 	/* Write new list of entries; deleted entries have been dropped. */
3891 	TAILQ_FOREACH(pe, &paths, entry) {
3892 		struct got_tree_entry *te = pe->data;
3893 		new_tree_entries.nentries++;
3894 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
3895 	}
3896 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
3897 done:
3898 	got_object_tree_entries_close(&new_tree_entries);
3899 	got_pathlist_free(&paths);
3900 	return err;
3901 }
3902 
3903 static const struct got_error *
3904 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
3905     struct got_object_id *new_base_commit_id, struct got_fileindex *fileindex)
3906 {
3907 	const struct got_error *err = NULL;
3908 	struct got_pathlist_entry *pe;
3909 
3910 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3911 		struct got_fileindex_entry *ie;
3912 		struct got_commitable *ct = pe->data;
3913 
3914 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
3915 		if (ie) {
3916 			if (ct->status == GOT_STATUS_DELETE ||
3917 			    ct->staged_status == GOT_STATUS_DELETE) {
3918 				got_fileindex_entry_remove(fileindex, ie);
3919 				got_fileindex_entry_free(ie);
3920 			} else if (ct->staged_status == GOT_STATUS_ADD ||
3921 			    ct->staged_status == GOT_STATUS_MODIFY) {
3922 				got_fileindex_entry_stage_set(ie,
3923 				    GOT_FILEIDX_STAGE_NONE);
3924 				err = got_fileindex_entry_update(ie,
3925 				    ct->ondisk_path, ct->staged_blob_id->sha1,
3926 				    new_base_commit_id->sha1, 1);
3927 			} else
3928 				err = got_fileindex_entry_update(ie,
3929 				    ct->ondisk_path, ct->blob_id->sha1,
3930 				    new_base_commit_id->sha1, 1);
3931 		} else {
3932 			err = got_fileindex_entry_alloc(&ie,
3933 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
3934 			    new_base_commit_id->sha1);
3935 			if (err)
3936 				break;
3937 			err = got_fileindex_entry_add(fileindex, ie);
3938 			if (err)
3939 				break;
3940 		}
3941 	}
3942 	return err;
3943 }
3944 
3945 
3946 static const struct got_error *
3947 check_out_of_date(const char *in_repo_path, unsigned char status,
3948     unsigned char staged_status, struct got_object_id *base_blob_id,
3949     struct got_object_id *base_commit_id,
3950     struct got_object_id *head_commit_id, struct got_repository *repo,
3951     int ood_errcode)
3952 {
3953 	const struct got_error *err = NULL;
3954 	struct got_object_id *id = NULL;
3955 
3956 	if (status != GOT_STATUS_ADD && staged_status != GOT_STATUS_ADD) {
3957 		/* Trivial case: base commit == head commit */
3958 		if (got_object_id_cmp(base_commit_id, head_commit_id) == 0)
3959 			return NULL;
3960 		/*
3961 		 * Ensure file content which local changes were based
3962 		 * on matches file content in the branch head.
3963 		 */
3964 		err = got_object_id_by_path(&id, repo, head_commit_id,
3965 		    in_repo_path);
3966 		if (err) {
3967 			if (err->code == GOT_ERR_NO_TREE_ENTRY)
3968 				err = got_error(ood_errcode);
3969 			goto done;
3970 		} else if (got_object_id_cmp(id, base_blob_id) != 0)
3971 			err = got_error(ood_errcode);
3972 	} else {
3973 		/* Require that added files don't exist in the branch head. */
3974 		err = got_object_id_by_path(&id, repo, head_commit_id,
3975 		    in_repo_path);
3976 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3977 			goto done;
3978 		err = id ? got_error(ood_errcode) : NULL;
3979 	}
3980 done:
3981 	free(id);
3982 	return err;
3983 }
3984 
3985 const struct got_error *
3986 commit_worktree(struct got_object_id **new_commit_id,
3987     struct got_pathlist_head *commitable_paths,
3988     struct got_object_id *head_commit_id, struct got_worktree *worktree,
3989     const char *author, const char *committer,
3990     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3991     got_worktree_status_cb status_cb, void *status_arg,
3992     struct got_repository *repo)
3993 {
3994 	const struct got_error *err = NULL, *unlockerr = NULL;
3995 	struct got_pathlist_entry *pe;
3996 	const char *head_ref_name = NULL;
3997 	struct got_commit_object *head_commit = NULL;
3998 	struct got_reference *head_ref2 = NULL;
3999 	struct got_object_id *head_commit_id2 = NULL;
4000 	struct got_tree_object *head_tree = NULL;
4001 	struct got_object_id *new_tree_id = NULL;
4002 	struct got_object_id_queue parent_ids;
4003 	struct got_object_qid *pid = NULL;
4004 	char *logmsg = NULL;
4005 
4006 	*new_commit_id = NULL;
4007 
4008 	SIMPLEQ_INIT(&parent_ids);
4009 
4010 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
4011 	if (err)
4012 		goto done;
4013 
4014 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
4015 	if (err)
4016 		goto done;
4017 
4018 	if (commit_msg_cb != NULL) {
4019 		err = commit_msg_cb(commitable_paths, &logmsg, commit_arg);
4020 		if (err)
4021 			goto done;
4022 	}
4023 
4024 	if (logmsg == NULL || strlen(logmsg) == 0) {
4025 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
4026 		goto done;
4027 	}
4028 
4029 	/* Create blobs from added and modified files and record their IDs. */
4030 	TAILQ_FOREACH(pe, commitable_paths, entry) {
4031 		struct got_commitable *ct = pe->data;
4032 		char *ondisk_path;
4033 
4034 		/* Blobs for staged files already exist. */
4035 		if (ct->staged_status == GOT_STATUS_ADD ||
4036 		    ct->staged_status == GOT_STATUS_MODIFY)
4037 			continue;
4038 
4039 		if (ct->status != GOT_STATUS_ADD &&
4040 		    ct->status != GOT_STATUS_MODIFY)
4041 			continue;
4042 
4043 		if (asprintf(&ondisk_path, "%s/%s",
4044 		    worktree->root_path, pe->path) == -1) {
4045 			err = got_error_from_errno("asprintf");
4046 			goto done;
4047 		}
4048 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
4049 		free(ondisk_path);
4050 		if (err)
4051 			goto done;
4052 	}
4053 
4054 	/* Recursively write new tree objects. */
4055 	err = write_tree(&new_tree_id, head_tree, "/", commitable_paths,
4056 	    status_cb, status_arg, repo);
4057 	if (err)
4058 		goto done;
4059 
4060 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
4061 	if (err)
4062 		goto done;
4063 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
4064 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
4065 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
4066 	got_object_qid_free(pid);
4067 	if (logmsg != NULL)
4068 		free(logmsg);
4069 	if (err)
4070 		goto done;
4071 
4072 	/* Check if a concurrent commit to our branch has occurred. */
4073 	head_ref_name = got_worktree_get_head_ref_name(worktree);
4074 	if (head_ref_name == NULL) {
4075 		err = got_error_from_errno("got_worktree_get_head_ref_name");
4076 		goto done;
4077 	}
4078 	/* Lock the reference here to prevent concurrent modification. */
4079 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
4080 	if (err)
4081 		goto done;
4082 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
4083 	if (err)
4084 		goto done;
4085 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
4086 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
4087 		goto done;
4088 	}
4089 	/* Update branch head in repository. */
4090 	err = got_ref_change_ref(head_ref2, *new_commit_id);
4091 	if (err)
4092 		goto done;
4093 	err = got_ref_write(head_ref2, repo);
4094 	if (err)
4095 		goto done;
4096 
4097 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
4098 	if (err)
4099 		goto done;
4100 
4101 	err = ref_base_commit(worktree, repo);
4102 	if (err)
4103 		goto done;
4104 done:
4105 	if (head_tree)
4106 		got_object_tree_close(head_tree);
4107 	if (head_commit)
4108 		got_object_commit_close(head_commit);
4109 	free(head_commit_id2);
4110 	if (head_ref2) {
4111 		unlockerr = got_ref_unlock(head_ref2);
4112 		if (unlockerr && err == NULL)
4113 			err = unlockerr;
4114 		got_ref_close(head_ref2);
4115 	}
4116 	return err;
4117 }
4118 
4119 static const struct got_error *
4120 check_path_is_commitable(const char *path,
4121     struct got_pathlist_head *commitable_paths)
4122 {
4123 	struct got_pathlist_entry *cpe = NULL;
4124 	size_t path_len = strlen(path);
4125 
4126 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
4127 		struct got_commitable *ct = cpe->data;
4128 		const char *ct_path = ct->path;
4129 
4130 		while (ct_path[0] == '/')
4131 			ct_path++;
4132 
4133 		if (strcmp(path, ct_path) == 0 ||
4134 		    got_path_is_child(ct_path, path, path_len))
4135 			break;
4136 	}
4137 
4138 	if (cpe == NULL)
4139 		return got_error_path(path, GOT_ERR_BAD_PATH);
4140 
4141 	return NULL;
4142 }
4143 
4144 static const struct got_error *
4145 check_staged_file(void *arg, struct got_fileindex_entry *ie)
4146 {
4147 	int *have_staged_files = arg;
4148 
4149 	if (got_fileindex_entry_stage_get(ie) != GOT_FILEIDX_STAGE_NONE) {
4150 		*have_staged_files = 1;
4151 		return got_error(GOT_ERR_CANCELLED);
4152 	}
4153 
4154 	return NULL;
4155 }
4156 
4157 static const struct got_error *
4158 check_non_staged_files(struct got_fileindex *fileindex,
4159     struct got_pathlist_head *paths)
4160 {
4161 	struct got_pathlist_entry *pe;
4162 	struct got_fileindex_entry *ie;
4163 
4164 	TAILQ_FOREACH(pe, paths, entry) {
4165 		if (pe->path[0] == '\0')
4166 			continue;
4167 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
4168 		if (ie == NULL)
4169 			return got_error_path(pe->path, GOT_ERR_BAD_PATH);
4170 		if (got_fileindex_entry_stage_get(ie) == GOT_FILEIDX_STAGE_NONE)
4171 			return got_error_path(pe->path,
4172 			    GOT_ERR_FILE_NOT_STAGED);
4173 	}
4174 
4175 	return NULL;
4176 }
4177 
4178 const struct got_error *
4179 got_worktree_commit(struct got_object_id **new_commit_id,
4180     struct got_worktree *worktree, struct got_pathlist_head *paths,
4181     const char *author, const char *committer,
4182     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
4183     got_worktree_status_cb status_cb, void *status_arg,
4184     struct got_repository *repo)
4185 {
4186 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
4187 	struct got_fileindex *fileindex = NULL;
4188 	char *fileindex_path = NULL;
4189 	struct got_pathlist_head commitable_paths;
4190 	struct collect_commitables_arg cc_arg;
4191 	struct got_pathlist_entry *pe;
4192 	struct got_reference *head_ref = NULL;
4193 	struct got_object_id *head_commit_id = NULL;
4194 	int have_staged_files = 0;
4195 
4196 	*new_commit_id = NULL;
4197 
4198 	TAILQ_INIT(&commitable_paths);
4199 
4200 	err = lock_worktree(worktree, LOCK_EX);
4201 	if (err)
4202 		goto done;
4203 
4204 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
4205 	if (err)
4206 		goto done;
4207 
4208 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
4209 	if (err)
4210 		goto done;
4211 
4212 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4213 	if (err)
4214 		goto done;
4215 
4216 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
4217 	    &have_staged_files);
4218 	if (err && err->code != GOT_ERR_CANCELLED)
4219 		goto done;
4220 	if (have_staged_files) {
4221 		err = check_non_staged_files(fileindex, paths);
4222 		if (err)
4223 			goto done;
4224 	}
4225 
4226 	cc_arg.commitable_paths = &commitable_paths;
4227 	cc_arg.worktree = worktree;
4228 	cc_arg.repo = repo;
4229 	cc_arg.have_staged_files = have_staged_files;
4230 	TAILQ_FOREACH(pe, paths, entry) {
4231 		err = worktree_status(worktree, pe->path, fileindex, repo,
4232 		    collect_commitables, &cc_arg, NULL, NULL);
4233 		if (err)
4234 			goto done;
4235 	}
4236 
4237 	if (TAILQ_EMPTY(&commitable_paths)) {
4238 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
4239 		goto done;
4240 	}
4241 
4242 	TAILQ_FOREACH(pe, paths, entry) {
4243 		err = check_path_is_commitable(pe->path, &commitable_paths);
4244 		if (err)
4245 			goto done;
4246 	}
4247 
4248 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
4249 		struct got_commitable *ct = pe->data;
4250 		const char *ct_path = ct->in_repo_path;
4251 
4252 		while (ct_path[0] == '/')
4253 			ct_path++;
4254 		err = check_out_of_date(ct_path, ct->status,
4255 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
4256 		    head_commit_id, repo, GOT_ERR_COMMIT_OUT_OF_DATE);
4257 		if (err)
4258 			goto done;
4259 
4260 	}
4261 
4262 	err = commit_worktree(new_commit_id, &commitable_paths,
4263 	    head_commit_id, worktree, author, committer,
4264 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
4265 	if (err)
4266 		goto done;
4267 
4268 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
4269 	    fileindex);
4270 	sync_err = sync_fileindex(fileindex, fileindex_path);
4271 	if (sync_err && err == NULL)
4272 		err = sync_err;
4273 done:
4274 	if (fileindex)
4275 		got_fileindex_free(fileindex);
4276 	free(fileindex_path);
4277 	unlockerr = lock_worktree(worktree, LOCK_SH);
4278 	if (unlockerr && err == NULL)
4279 		err = unlockerr;
4280 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
4281 		struct got_commitable *ct = pe->data;
4282 		free_commitable(ct);
4283 	}
4284 	got_pathlist_free(&commitable_paths);
4285 	return err;
4286 }
4287 
4288 const char *
4289 got_commitable_get_path(struct got_commitable *ct)
4290 {
4291 	return ct->path;
4292 }
4293 
4294 unsigned int
4295 got_commitable_get_status(struct got_commitable *ct)
4296 {
4297 	return ct->status;
4298 }
4299 
4300 struct check_rebase_ok_arg {
4301 	struct got_worktree *worktree;
4302 	struct got_repository *repo;
4303 };
4304 
4305 static const struct got_error *
4306 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
4307 {
4308 	const struct got_error *err = NULL;
4309 	struct check_rebase_ok_arg *a = arg;
4310 	unsigned char status;
4311 	struct stat sb;
4312 	char *ondisk_path;
4313 
4314 	/* Reject rebase of a work tree with mixed base commits. */
4315 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
4316 	    SHA1_DIGEST_LENGTH))
4317 		return got_error(GOT_ERR_MIXED_COMMITS);
4318 
4319 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
4320 	    == -1)
4321 		return got_error_from_errno("asprintf");
4322 
4323 	/* Reject rebase of a work tree with modified or staged files. */
4324 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
4325 	free(ondisk_path);
4326 	if (err)
4327 		return err;
4328 
4329 	if (status != GOT_STATUS_NO_CHANGE)
4330 		return got_error(GOT_ERR_MODIFIED);
4331 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
4332 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
4333 
4334 	return NULL;
4335 }
4336 
4337 const struct got_error *
4338 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
4339     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
4340     struct got_worktree *worktree, struct got_reference *branch,
4341     struct got_repository *repo)
4342 {
4343 	const struct got_error *err = NULL;
4344 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
4345 	char *branch_ref_name = NULL;
4346 	char *fileindex_path = NULL;
4347 	struct check_rebase_ok_arg ok_arg;
4348 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
4349 
4350 	*new_base_branch_ref = NULL;
4351 	*tmp_branch = NULL;
4352 	*fileindex = NULL;
4353 
4354 	err = lock_worktree(worktree, LOCK_EX);
4355 	if (err)
4356 		return err;
4357 
4358 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4359 	if (err)
4360 		goto done;
4361 
4362 	ok_arg.worktree = worktree;
4363 	ok_arg.repo = repo;
4364 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
4365 	    &ok_arg);
4366 	if (err)
4367 		goto done;
4368 
4369 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4370 	if (err)
4371 		goto done;
4372 
4373 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
4374 	if (err)
4375 		goto done;
4376 
4377 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
4378 	if (err)
4379 		goto done;
4380 
4381 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
4382 	    0);
4383 	if (err)
4384 		goto done;
4385 
4386 	err = got_ref_alloc_symref(new_base_branch_ref,
4387 	    new_base_branch_ref_name, wt_branch);
4388 	if (err)
4389 		goto done;
4390 	err = got_ref_write(*new_base_branch_ref, repo);
4391 	if (err)
4392 		goto done;
4393 
4394 	/* TODO Lock original branch's ref while rebasing? */
4395 
4396 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
4397 	if (err)
4398 		goto done;
4399 
4400 	err = got_ref_write(branch_ref, repo);
4401 	if (err)
4402 		goto done;
4403 
4404 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
4405 	    worktree->base_commit_id);
4406 	if (err)
4407 		goto done;
4408 	err = got_ref_write(*tmp_branch, repo);
4409 	if (err)
4410 		goto done;
4411 
4412 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
4413 	if (err)
4414 		goto done;
4415 done:
4416 	free(fileindex_path);
4417 	free(tmp_branch_name);
4418 	free(new_base_branch_ref_name);
4419 	free(branch_ref_name);
4420 	if (branch_ref)
4421 		got_ref_close(branch_ref);
4422 	if (wt_branch)
4423 		got_ref_close(wt_branch);
4424 	if (err) {
4425 		if (*new_base_branch_ref) {
4426 			got_ref_close(*new_base_branch_ref);
4427 			*new_base_branch_ref = NULL;
4428 		}
4429 		if (*tmp_branch) {
4430 			got_ref_close(*tmp_branch);
4431 			*tmp_branch = NULL;
4432 		}
4433 		if (*fileindex) {
4434 			got_fileindex_free(*fileindex);
4435 			*fileindex = NULL;
4436 		}
4437 		lock_worktree(worktree, LOCK_SH);
4438 	}
4439 	return err;
4440 }
4441 
4442 const struct got_error *
4443 got_worktree_rebase_continue(struct got_object_id **commit_id,
4444     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
4445     struct got_reference **branch, struct got_fileindex **fileindex,
4446     struct got_worktree *worktree, struct got_repository *repo)
4447 {
4448 	const struct got_error *err;
4449 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
4450 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
4451 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
4452 	char *fileindex_path = NULL;
4453 	int have_staged_files = 0;
4454 
4455 	*commit_id = NULL;
4456 	*new_base_branch = NULL;
4457 	*tmp_branch = NULL;
4458 	*branch = NULL;
4459 	*fileindex = NULL;
4460 
4461 	err = lock_worktree(worktree, LOCK_EX);
4462 	if (err)
4463 		return err;
4464 
4465 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4466 	if (err)
4467 		goto done;
4468 
4469 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
4470 	    &have_staged_files);
4471 	if (err && err->code != GOT_ERR_CANCELLED)
4472 		goto done;
4473 	if (have_staged_files) {
4474 		err = got_error(GOT_ERR_STAGED_PATHS);
4475 		goto done;
4476 	}
4477 
4478 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4479 	if (err)
4480 		goto done;
4481 
4482 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
4483 	if (err)
4484 		goto done;
4485 
4486 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4487 	if (err)
4488 		goto done;
4489 
4490 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
4491 	if (err)
4492 		goto done;
4493 
4494 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
4495 	if (err)
4496 		goto done;
4497 
4498 	err = got_ref_open(branch, repo,
4499 	    got_ref_get_symref_target(branch_ref), 0);
4500 	if (err)
4501 		goto done;
4502 
4503 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4504 	if (err)
4505 		goto done;
4506 
4507 	err = got_ref_resolve(commit_id, repo, commit_ref);
4508 	if (err)
4509 		goto done;
4510 
4511 	err = got_ref_open(new_base_branch, repo,
4512 	    new_base_branch_ref_name, 0);
4513 	if (err)
4514 		goto done;
4515 
4516 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
4517 	if (err)
4518 		goto done;
4519 done:
4520 	free(commit_ref_name);
4521 	free(branch_ref_name);
4522 	free(fileindex_path);
4523 	if (commit_ref)
4524 		got_ref_close(commit_ref);
4525 	if (branch_ref)
4526 		got_ref_close(branch_ref);
4527 	if (err) {
4528 		free(*commit_id);
4529 		*commit_id = NULL;
4530 		if (*tmp_branch) {
4531 			got_ref_close(*tmp_branch);
4532 			*tmp_branch = NULL;
4533 		}
4534 		if (*new_base_branch) {
4535 			got_ref_close(*new_base_branch);
4536 			*new_base_branch = NULL;
4537 		}
4538 		if (*branch) {
4539 			got_ref_close(*branch);
4540 			*branch = NULL;
4541 		}
4542 		if (*fileindex) {
4543 			got_fileindex_free(*fileindex);
4544 			*fileindex = NULL;
4545 		}
4546 		lock_worktree(worktree, LOCK_SH);
4547 	}
4548 	return err;
4549 }
4550 
4551 const struct got_error *
4552 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
4553 {
4554 	const struct got_error *err;
4555 	char *tmp_branch_name = NULL;
4556 
4557 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4558 	if (err)
4559 		return err;
4560 
4561 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
4562 	free(tmp_branch_name);
4563 	return NULL;
4564 }
4565 
4566 static const struct got_error *
4567 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
4568     char **logmsg, void *arg)
4569 {
4570 	*logmsg = arg;
4571 	return NULL;
4572 }
4573 
4574 static const struct got_error *
4575 rebase_status(void *arg, unsigned char status, unsigned char staged_status,
4576     const char *path, struct got_object_id *blob_id,
4577     struct got_object_id *staged_blob_id, struct got_object_id *commit_id)
4578 {
4579 	return NULL;
4580 }
4581 
4582 struct collect_merged_paths_arg {
4583 	got_worktree_checkout_cb progress_cb;
4584 	void *progress_arg;
4585 	struct got_pathlist_head *merged_paths;
4586 };
4587 
4588 static const struct got_error *
4589 collect_merged_paths(void *arg, unsigned char status, const char *path)
4590 {
4591 	const struct got_error *err;
4592 	struct collect_merged_paths_arg *a = arg;
4593 	char *p;
4594 	struct got_pathlist_entry *new;
4595 
4596 	err = (*a->progress_cb)(a->progress_arg, status, path);
4597 	if (err)
4598 		return err;
4599 
4600 	if (status != GOT_STATUS_MERGE &&
4601 	    status != GOT_STATUS_ADD &&
4602 	    status != GOT_STATUS_DELETE &&
4603 	    status != GOT_STATUS_CONFLICT)
4604 		return NULL;
4605 
4606 	p = strdup(path);
4607 	if (p == NULL)
4608 		return got_error_from_errno("strdup");
4609 
4610 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
4611 	if (err || new == NULL)
4612 		free(p);
4613 	return err;
4614 }
4615 
4616 void
4617 got_worktree_rebase_pathlist_free(struct got_pathlist_head *merged_paths)
4618 {
4619 	struct got_pathlist_entry *pe;
4620 
4621 	TAILQ_FOREACH(pe, merged_paths, entry)
4622 		free((char *)pe->path);
4623 
4624 	got_pathlist_free(merged_paths);
4625 }
4626 
4627 static const struct got_error *
4628 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
4629     struct got_repository *repo)
4630 {
4631 	const struct got_error *err;
4632 	struct got_reference *commit_ref = NULL;
4633 
4634 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4635 	if (err) {
4636 		if (err->code != GOT_ERR_NOT_REF)
4637 			goto done;
4638 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
4639 		if (err)
4640 			goto done;
4641 		err = got_ref_write(commit_ref, repo);
4642 		if (err)
4643 			goto done;
4644 	} else {
4645 		struct got_object_id *stored_id;
4646 		int cmp;
4647 
4648 		err = got_ref_resolve(&stored_id, repo, commit_ref);
4649 		if (err)
4650 			goto done;
4651 		cmp = got_object_id_cmp(commit_id, stored_id);
4652 		free(stored_id);
4653 		if (cmp != 0) {
4654 			err = got_error(GOT_ERR_REBASE_COMMITID);
4655 			goto done;
4656 		}
4657 	}
4658 done:
4659 	if (commit_ref)
4660 		got_ref_close(commit_ref);
4661 	return err;
4662 }
4663 
4664 static const struct got_error *
4665 rebase_merge_files(struct got_pathlist_head *merged_paths,
4666     const char *commit_ref_name, struct got_worktree *worktree,
4667     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
4668     struct got_object_id *commit_id, struct got_repository *repo,
4669     got_worktree_checkout_cb progress_cb, void *progress_arg,
4670     got_cancel_cb cancel_cb, void *cancel_arg)
4671 {
4672 	const struct got_error *err;
4673 	struct got_reference *commit_ref = NULL;
4674 	struct collect_merged_paths_arg cmp_arg;
4675 	char *fileindex_path;
4676 
4677 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
4678 
4679 	err = get_fileindex_path(&fileindex_path, worktree);
4680 	if (err)
4681 		return err;
4682 
4683 	cmp_arg.progress_cb = progress_cb;
4684 	cmp_arg.progress_arg = progress_arg;
4685 	cmp_arg.merged_paths = merged_paths;
4686 	err = merge_files(worktree, fileindex, fileindex_path,
4687 	    parent_commit_id, commit_id, repo, collect_merged_paths,
4688 	    &cmp_arg, cancel_cb, cancel_arg);
4689 	if (commit_ref)
4690 		got_ref_close(commit_ref);
4691 	return err;
4692 }
4693 
4694 const struct got_error *
4695 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
4696     struct got_worktree *worktree, struct got_fileindex *fileindex,
4697     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
4698     struct got_repository *repo,
4699     got_worktree_checkout_cb progress_cb, void *progress_arg,
4700     got_cancel_cb cancel_cb, void *cancel_arg)
4701 {
4702 	const struct got_error *err;
4703 	char *commit_ref_name;
4704 
4705 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4706 	if (err)
4707 		return err;
4708 
4709 	err = store_commit_id(commit_ref_name, commit_id, repo);
4710 	if (err)
4711 		goto done;
4712 
4713 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4714 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4715 	    progress_arg, cancel_cb, cancel_arg);
4716 done:
4717 	free(commit_ref_name);
4718 	return err;
4719 }
4720 
4721 const struct got_error *
4722 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
4723     struct got_worktree *worktree, struct got_fileindex *fileindex,
4724     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
4725     struct got_repository *repo,
4726     got_worktree_checkout_cb progress_cb, void *progress_arg,
4727     got_cancel_cb cancel_cb, void *cancel_arg)
4728 {
4729 	const struct got_error *err;
4730 	char *commit_ref_name;
4731 
4732 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4733 	if (err)
4734 		return err;
4735 
4736 	err = store_commit_id(commit_ref_name, commit_id, repo);
4737 	if (err)
4738 		goto done;
4739 
4740 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4741 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4742 	    progress_arg, cancel_cb, cancel_arg);
4743 done:
4744 	free(commit_ref_name);
4745 	return err;
4746 }
4747 
4748 static const struct got_error *
4749 rebase_commit(struct got_object_id **new_commit_id,
4750     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
4751     struct got_worktree *worktree, struct got_fileindex *fileindex,
4752     struct got_reference *tmp_branch, struct got_commit_object *orig_commit,
4753     const char *new_logmsg, struct got_repository *repo)
4754 {
4755 	const struct got_error *err, *sync_err;
4756 	struct got_pathlist_head commitable_paths;
4757 	struct collect_commitables_arg cc_arg;
4758 	char *fileindex_path = NULL;
4759 	struct got_reference *head_ref = NULL;
4760 	struct got_object_id *head_commit_id = NULL;
4761 	char *logmsg = NULL;
4762 
4763 	TAILQ_INIT(&commitable_paths);
4764 	*new_commit_id = NULL;
4765 
4766 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
4767 
4768 	err = get_fileindex_path(&fileindex_path, worktree);
4769 	if (err)
4770 		return err;
4771 
4772 	cc_arg.commitable_paths = &commitable_paths;
4773 	cc_arg.worktree = worktree;
4774 	cc_arg.repo = repo;
4775 	cc_arg.have_staged_files = 0;
4776 	/*
4777 	 * If possible get the status of individual files directly to
4778 	 * avoid crawling the entire work tree once per rebased commit.
4779 	 * TODO: Ideally, merged_paths would contain a list of commitables
4780 	 * we could use so we could skip worktree_status() entirely.
4781 	 */
4782 	if (merged_paths) {
4783 		struct got_pathlist_entry *pe;
4784 		if (TAILQ_EMPTY(merged_paths)) {
4785 			err = got_error(GOT_ERR_NO_MERGED_PATHS);
4786 			goto done;
4787 		}
4788 		TAILQ_FOREACH(pe, merged_paths, entry) {
4789 			err = worktree_status(worktree, pe->path, fileindex,
4790 			    repo, collect_commitables, &cc_arg, NULL, NULL);
4791 			if (err)
4792 				goto done;
4793 		}
4794 	} else {
4795 		err = worktree_status(worktree, "", fileindex, repo,
4796 		    collect_commitables, &cc_arg, NULL, NULL);
4797 		if (err)
4798 			goto done;
4799 	}
4800 
4801 	if (TAILQ_EMPTY(&commitable_paths)) {
4802 		/* No-op change; commit will be elided. */
4803 		err = got_ref_delete(commit_ref, repo);
4804 		if (err)
4805 			goto done;
4806 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
4807 		goto done;
4808 	}
4809 
4810 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
4811 	if (err)
4812 		goto done;
4813 
4814 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
4815 	if (err)
4816 		goto done;
4817 
4818 	if (new_logmsg) {
4819 		logmsg = strdup(new_logmsg);
4820 		if (logmsg == NULL) {
4821 			err = got_error_from_errno("strdup");
4822 			goto done;
4823 		}
4824 	} else {
4825 		err = got_object_commit_get_logmsg(&logmsg, orig_commit);
4826 		if (err)
4827 			goto done;
4828 	}
4829 
4830 	/* NB: commit_worktree will call free(logmsg) */
4831 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
4832 	    worktree, got_object_commit_get_author(orig_commit),
4833 	    got_object_commit_get_committer(orig_commit),
4834 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
4835 	if (err)
4836 		goto done;
4837 
4838 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
4839 	if (err)
4840 		goto done;
4841 
4842 	err = got_ref_delete(commit_ref, repo);
4843 	if (err)
4844 		goto done;
4845 
4846 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
4847 	    fileindex);
4848 	sync_err = sync_fileindex(fileindex, fileindex_path);
4849 	if (sync_err && err == NULL)
4850 		err = sync_err;
4851 done:
4852 	free(fileindex_path);
4853 	free(head_commit_id);
4854 	if (head_ref)
4855 		got_ref_close(head_ref);
4856 	if (err) {
4857 		free(*new_commit_id);
4858 		*new_commit_id = NULL;
4859 	}
4860 	return err;
4861 }
4862 
4863 const struct got_error *
4864 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
4865     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4866     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4867     struct got_commit_object *orig_commit,
4868     struct got_object_id *orig_commit_id, struct got_repository *repo)
4869 {
4870 	const struct got_error *err;
4871 	char *commit_ref_name;
4872 	struct got_reference *commit_ref = NULL;
4873 	struct got_object_id *commit_id = NULL;
4874 
4875 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4876 	if (err)
4877 		return err;
4878 
4879 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4880 	if (err)
4881 		goto done;
4882 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4883 	if (err)
4884 		goto done;
4885 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4886 		err = got_error(GOT_ERR_REBASE_COMMITID);
4887 		goto done;
4888 	}
4889 
4890 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4891 	    worktree, fileindex, tmp_branch, orig_commit, NULL, repo);
4892 done:
4893 	if (commit_ref)
4894 		got_ref_close(commit_ref);
4895 	free(commit_ref_name);
4896 	free(commit_id);
4897 	return err;
4898 }
4899 
4900 const struct got_error *
4901 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
4902     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4903     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4904     struct got_commit_object *orig_commit,
4905     struct got_object_id *orig_commit_id, const char *new_logmsg,
4906     struct got_repository *repo)
4907 {
4908 	const struct got_error *err;
4909 	char *commit_ref_name;
4910 	struct got_reference *commit_ref = NULL;
4911 	struct got_object_id *commit_id = NULL;
4912 
4913 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4914 	if (err)
4915 		return err;
4916 
4917 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4918 	if (err)
4919 		goto done;
4920 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4921 	if (err)
4922 		goto done;
4923 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4924 		err = got_error(GOT_ERR_HISTEDIT_COMMITID);
4925 		goto done;
4926 	}
4927 
4928 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4929 	    worktree, fileindex, tmp_branch, orig_commit, new_logmsg, repo);
4930 done:
4931 	if (commit_ref)
4932 		got_ref_close(commit_ref);
4933 	free(commit_ref_name);
4934 	free(commit_id);
4935 	return err;
4936 }
4937 
4938 const struct got_error *
4939 got_worktree_rebase_postpone(struct got_worktree *worktree,
4940     struct got_fileindex *fileindex)
4941 {
4942 	if (fileindex)
4943 		got_fileindex_free(fileindex);
4944 	return lock_worktree(worktree, LOCK_SH);
4945 }
4946 
4947 static const struct got_error *
4948 delete_ref(const char *name, struct got_repository *repo)
4949 {
4950 	const struct got_error *err;
4951 	struct got_reference *ref;
4952 
4953 	err = got_ref_open(&ref, repo, name, 0);
4954 	if (err) {
4955 		if (err->code == GOT_ERR_NOT_REF)
4956 			return NULL;
4957 		return err;
4958 	}
4959 
4960 	err = got_ref_delete(ref, repo);
4961 	got_ref_close(ref);
4962 	return err;
4963 }
4964 
4965 static const struct got_error *
4966 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
4967 {
4968 	const struct got_error *err;
4969 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
4970 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
4971 
4972 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4973 	if (err)
4974 		goto done;
4975 	err = delete_ref(tmp_branch_name, repo);
4976 	if (err)
4977 		goto done;
4978 
4979 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
4980 	if (err)
4981 		goto done;
4982 	err = delete_ref(new_base_branch_ref_name, repo);
4983 	if (err)
4984 		goto done;
4985 
4986 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
4987 	if (err)
4988 		goto done;
4989 	err = delete_ref(branch_ref_name, repo);
4990 	if (err)
4991 		goto done;
4992 
4993 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4994 	if (err)
4995 		goto done;
4996 	err = delete_ref(commit_ref_name, repo);
4997 	if (err)
4998 		goto done;
4999 
5000 done:
5001 	free(tmp_branch_name);
5002 	free(new_base_branch_ref_name);
5003 	free(branch_ref_name);
5004 	free(commit_ref_name);
5005 	return err;
5006 }
5007 
5008 const struct got_error *
5009 got_worktree_rebase_complete(struct got_worktree *worktree,
5010     struct got_fileindex *fileindex, struct got_reference *new_base_branch,
5011     struct got_reference *tmp_branch, struct got_reference *rebased_branch,
5012     struct got_repository *repo)
5013 {
5014 	const struct got_error *err, *unlockerr;
5015 	struct got_object_id *new_head_commit_id = NULL;
5016 
5017 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
5018 	if (err)
5019 		return err;
5020 
5021 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
5022 	if (err)
5023 		goto done;
5024 
5025 	err = got_ref_write(rebased_branch, repo);
5026 	if (err)
5027 		goto done;
5028 
5029 	err = got_worktree_set_head_ref(worktree, rebased_branch);
5030 	if (err)
5031 		goto done;
5032 
5033 	err = delete_rebase_refs(worktree, repo);
5034 done:
5035 	if (fileindex)
5036 		got_fileindex_free(fileindex);
5037 	free(new_head_commit_id);
5038 	unlockerr = lock_worktree(worktree, LOCK_SH);
5039 	if (unlockerr && err == NULL)
5040 		err = unlockerr;
5041 	return err;
5042 }
5043 
5044 const struct got_error *
5045 got_worktree_rebase_abort(struct got_worktree *worktree,
5046     struct got_fileindex *fileindex, struct got_repository *repo,
5047     struct got_reference *new_base_branch,
5048      got_worktree_checkout_cb progress_cb, void *progress_arg)
5049 {
5050 	const struct got_error *err, *unlockerr, *sync_err;
5051 	struct got_reference *resolved = NULL;
5052 	struct got_object_id *commit_id = NULL;
5053 	char *fileindex_path = NULL;
5054 	struct revert_file_args rfa;
5055 	struct got_object_id *tree_id = NULL;
5056 
5057 	err = lock_worktree(worktree, LOCK_EX);
5058 	if (err)
5059 		return err;
5060 
5061 	err = got_ref_open(&resolved, repo,
5062 	    got_ref_get_symref_target(new_base_branch), 0);
5063 	if (err)
5064 		goto done;
5065 
5066 	err = got_worktree_set_head_ref(worktree, resolved);
5067 	if (err)
5068 		goto done;
5069 
5070 	/*
5071 	 * XXX commits to the base branch could have happened while
5072 	 * we were busy rebasing; should we store the original commit ID
5073 	 * when rebase begins and read it back here?
5074 	 */
5075 	err = got_ref_resolve(&commit_id, repo, resolved);
5076 	if (err)
5077 		goto done;
5078 
5079 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
5080 	if (err)
5081 		goto done;
5082 
5083 	err = got_object_id_by_path(&tree_id, repo,
5084 	    worktree->base_commit_id, worktree->path_prefix);
5085 	if (err)
5086 		goto done;
5087 
5088 	err = delete_rebase_refs(worktree, repo);
5089 	if (err)
5090 		goto done;
5091 
5092 	err = get_fileindex_path(&fileindex_path, worktree);
5093 	if (err)
5094 		goto done;
5095 
5096 	rfa.worktree = worktree;
5097 	rfa.fileindex = fileindex;
5098 	rfa.progress_cb = progress_cb;
5099 	rfa.progress_arg = progress_arg;
5100 	rfa.patch_cb = NULL;
5101 	rfa.patch_arg = NULL;
5102 	rfa.repo = repo;
5103 	err = worktree_status(worktree, "", fileindex, repo,
5104 	    revert_file, &rfa, NULL, NULL);
5105 	if (err)
5106 		goto sync;
5107 
5108 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
5109 	    repo, progress_cb, progress_arg, NULL, NULL);
5110 sync:
5111 	sync_err = sync_fileindex(fileindex, fileindex_path);
5112 	if (sync_err && err == NULL)
5113 		err = sync_err;
5114 done:
5115 	got_ref_close(resolved);
5116 	free(tree_id);
5117 	free(commit_id);
5118 	if (fileindex)
5119 		got_fileindex_free(fileindex);
5120 	free(fileindex_path);
5121 
5122 	unlockerr = lock_worktree(worktree, LOCK_SH);
5123 	if (unlockerr && err == NULL)
5124 		err = unlockerr;
5125 	return err;
5126 }
5127 
5128 const struct got_error *
5129 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
5130     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
5131     struct got_fileindex **fileindex, struct got_worktree *worktree,
5132     struct got_repository *repo)
5133 {
5134 	const struct got_error *err = NULL;
5135 	char *tmp_branch_name = NULL;
5136 	char *branch_ref_name = NULL;
5137 	char *base_commit_ref_name = NULL;
5138 	char *fileindex_path = NULL;
5139 	struct check_rebase_ok_arg ok_arg;
5140 	struct got_reference *wt_branch = NULL;
5141 	struct got_reference *base_commit_ref = NULL;
5142 
5143 	*tmp_branch = NULL;
5144 	*branch_ref = NULL;
5145 	*base_commit_id = NULL;
5146 	*fileindex = NULL;
5147 
5148 	err = lock_worktree(worktree, LOCK_EX);
5149 	if (err)
5150 		return err;
5151 
5152 	err = open_fileindex(fileindex, &fileindex_path, worktree);
5153 	if (err)
5154 		goto done;
5155 
5156 	ok_arg.worktree = worktree;
5157 	ok_arg.repo = repo;
5158 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
5159 	    &ok_arg);
5160 	if (err)
5161 		goto done;
5162 
5163 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
5164 	if (err)
5165 		goto done;
5166 
5167 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
5168 	if (err)
5169 		goto done;
5170 
5171 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
5172 	    worktree);
5173 	if (err)
5174 		goto done;
5175 
5176 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
5177 	    0);
5178 	if (err)
5179 		goto done;
5180 
5181 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
5182 	if (err)
5183 		goto done;
5184 
5185 	err = got_ref_write(*branch_ref, repo);
5186 	if (err)
5187 		goto done;
5188 
5189 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
5190 	    worktree->base_commit_id);
5191 	if (err)
5192 		goto done;
5193 	err = got_ref_write(base_commit_ref, repo);
5194 	if (err)
5195 		goto done;
5196 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
5197 	if (*base_commit_id == NULL) {
5198 		err = got_error_from_errno("got_object_id_dup");
5199 		goto done;
5200 	}
5201 
5202 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
5203 	    worktree->base_commit_id);
5204 	if (err)
5205 		goto done;
5206 	err = got_ref_write(*tmp_branch, repo);
5207 	if (err)
5208 		goto done;
5209 
5210 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
5211 	if (err)
5212 		goto done;
5213 done:
5214 	free(fileindex_path);
5215 	free(tmp_branch_name);
5216 	free(branch_ref_name);
5217 	free(base_commit_ref_name);
5218 	if (wt_branch)
5219 		got_ref_close(wt_branch);
5220 	if (err) {
5221 		if (*branch_ref) {
5222 			got_ref_close(*branch_ref);
5223 			*branch_ref = NULL;
5224 		}
5225 		if (*tmp_branch) {
5226 			got_ref_close(*tmp_branch);
5227 			*tmp_branch = NULL;
5228 		}
5229 		free(*base_commit_id);
5230 		if (*fileindex) {
5231 			got_fileindex_free(*fileindex);
5232 			*fileindex = NULL;
5233 		}
5234 		lock_worktree(worktree, LOCK_SH);
5235 	}
5236 	return err;
5237 }
5238 
5239 const struct got_error *
5240 got_worktree_histedit_postpone(struct got_worktree *worktree,
5241     struct got_fileindex *fileindex)
5242 {
5243 	if (fileindex)
5244 		got_fileindex_free(fileindex);
5245 	return lock_worktree(worktree, LOCK_SH);
5246 }
5247 
5248 const struct got_error *
5249 got_worktree_histedit_in_progress(int *in_progress,
5250     struct got_worktree *worktree)
5251 {
5252 	const struct got_error *err;
5253 	char *tmp_branch_name = NULL;
5254 
5255 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
5256 	if (err)
5257 		return err;
5258 
5259 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
5260 	free(tmp_branch_name);
5261 	return NULL;
5262 }
5263 
5264 const struct got_error *
5265 got_worktree_histedit_continue(struct got_object_id **commit_id,
5266     struct got_reference **tmp_branch, struct got_reference **branch_ref,
5267     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
5268     struct got_worktree *worktree, struct got_repository *repo)
5269 {
5270 	const struct got_error *err;
5271 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
5272 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
5273 	struct got_reference *commit_ref = NULL;
5274 	struct got_reference *base_commit_ref = NULL;
5275 	char *fileindex_path = NULL;
5276 	int have_staged_files = 0;
5277 
5278 	*commit_id = NULL;
5279 	*tmp_branch = NULL;
5280 	*base_commit_id = NULL;
5281 	*fileindex = NULL;
5282 
5283 	err = lock_worktree(worktree, LOCK_EX);
5284 	if (err)
5285 		return err;
5286 
5287 	err = open_fileindex(fileindex, &fileindex_path, worktree);
5288 	if (err)
5289 		goto done;
5290 
5291 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
5292 	    &have_staged_files);
5293 	if (err && err->code != GOT_ERR_CANCELLED)
5294 		goto done;
5295 	if (have_staged_files) {
5296 		err = got_error(GOT_ERR_STAGED_PATHS);
5297 		goto done;
5298 	}
5299 
5300 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
5301 	if (err)
5302 		goto done;
5303 
5304 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
5305 	if (err)
5306 		goto done;
5307 
5308 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
5309 	if (err)
5310 		goto done;
5311 
5312 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
5313 	    worktree);
5314 	if (err)
5315 		goto done;
5316 
5317 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
5318 	if (err)
5319 		goto done;
5320 
5321 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
5322 	if (err)
5323 		goto done;
5324 	err = got_ref_resolve(commit_id, repo, commit_ref);
5325 	if (err)
5326 		goto done;
5327 
5328 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
5329 	if (err)
5330 		goto done;
5331 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
5332 	if (err)
5333 		goto done;
5334 
5335 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
5336 	if (err)
5337 		goto done;
5338 done:
5339 	free(commit_ref_name);
5340 	free(branch_ref_name);
5341 	free(fileindex_path);
5342 	if (commit_ref)
5343 		got_ref_close(commit_ref);
5344 	if (base_commit_ref)
5345 		got_ref_close(base_commit_ref);
5346 	if (err) {
5347 		free(*commit_id);
5348 		*commit_id = NULL;
5349 		free(*base_commit_id);
5350 		*base_commit_id = NULL;
5351 		if (*tmp_branch) {
5352 			got_ref_close(*tmp_branch);
5353 			*tmp_branch = NULL;
5354 		}
5355 		if (*fileindex) {
5356 			got_fileindex_free(*fileindex);
5357 			*fileindex = NULL;
5358 		}
5359 		lock_worktree(worktree, LOCK_EX);
5360 	}
5361 	return err;
5362 }
5363 
5364 static const struct got_error *
5365 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
5366 {
5367 	const struct got_error *err;
5368 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
5369 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
5370 
5371 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
5372 	if (err)
5373 		goto done;
5374 	err = delete_ref(tmp_branch_name, repo);
5375 	if (err)
5376 		goto done;
5377 
5378 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
5379 	    worktree);
5380 	if (err)
5381 		goto done;
5382 	err = delete_ref(base_commit_ref_name, repo);
5383 	if (err)
5384 		goto done;
5385 
5386 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
5387 	if (err)
5388 		goto done;
5389 	err = delete_ref(branch_ref_name, repo);
5390 	if (err)
5391 		goto done;
5392 
5393 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
5394 	if (err)
5395 		goto done;
5396 	err = delete_ref(commit_ref_name, repo);
5397 	if (err)
5398 		goto done;
5399 done:
5400 	free(tmp_branch_name);
5401 	free(base_commit_ref_name);
5402 	free(branch_ref_name);
5403 	free(commit_ref_name);
5404 	return err;
5405 }
5406 
5407 const struct got_error *
5408 got_worktree_histedit_abort(struct got_worktree *worktree,
5409     struct got_fileindex *fileindex, struct got_repository *repo,
5410     struct got_reference *branch, struct got_object_id *base_commit_id,
5411     got_worktree_checkout_cb progress_cb, void *progress_arg)
5412 {
5413 	const struct got_error *err, *unlockerr, *sync_err;
5414 	struct got_reference *resolved = NULL;
5415 	char *fileindex_path = NULL;
5416 	struct got_object_id *tree_id = NULL;
5417 	struct revert_file_args rfa;
5418 
5419 	err = lock_worktree(worktree, LOCK_EX);
5420 	if (err)
5421 		return err;
5422 
5423 	err = got_ref_open(&resolved, repo,
5424 	    got_ref_get_symref_target(branch), 0);
5425 	if (err)
5426 		goto done;
5427 
5428 	err = got_worktree_set_head_ref(worktree, resolved);
5429 	if (err)
5430 		goto done;
5431 
5432 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
5433 	if (err)
5434 		goto done;
5435 
5436 	err = got_object_id_by_path(&tree_id, repo, base_commit_id,
5437 	    worktree->path_prefix);
5438 	if (err)
5439 		goto done;
5440 
5441 	err = delete_histedit_refs(worktree, repo);
5442 	if (err)
5443 		goto done;
5444 
5445 	err = get_fileindex_path(&fileindex_path, worktree);
5446 	if (err)
5447 		goto done;
5448 
5449 	rfa.worktree = worktree;
5450 	rfa.fileindex = fileindex;
5451 	rfa.progress_cb = progress_cb;
5452 	rfa.progress_arg = progress_arg;
5453 	rfa.patch_cb = NULL;
5454 	rfa.patch_arg = NULL;
5455 	rfa.repo = repo;
5456 	err = worktree_status(worktree, "", fileindex, repo,
5457 	    revert_file, &rfa, NULL, NULL);
5458 	if (err)
5459 		goto sync;
5460 
5461 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
5462 	    repo, progress_cb, progress_arg, NULL, NULL);
5463 sync:
5464 	sync_err = sync_fileindex(fileindex, fileindex_path);
5465 	if (sync_err && err == NULL)
5466 		err = sync_err;
5467 done:
5468 	got_ref_close(resolved);
5469 	free(tree_id);
5470 	free(fileindex_path);
5471 
5472 	unlockerr = lock_worktree(worktree, LOCK_SH);
5473 	if (unlockerr && err == NULL)
5474 		err = unlockerr;
5475 	return err;
5476 }
5477 
5478 const struct got_error *
5479 got_worktree_histedit_complete(struct got_worktree *worktree,
5480     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
5481     struct got_reference *edited_branch, struct got_repository *repo)
5482 {
5483 	const struct got_error *err, *unlockerr;
5484 	struct got_object_id *new_head_commit_id = NULL;
5485 	struct got_reference *resolved = NULL;
5486 
5487 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
5488 	if (err)
5489 		return err;
5490 
5491 	err = got_ref_open(&resolved, repo,
5492 	    got_ref_get_symref_target(edited_branch), 0);
5493 	if (err)
5494 		goto done;
5495 
5496 	err = got_ref_change_ref(resolved, new_head_commit_id);
5497 	if (err)
5498 		goto done;
5499 
5500 	err = got_ref_write(resolved, repo);
5501 	if (err)
5502 		goto done;
5503 
5504 	err = got_worktree_set_head_ref(worktree, resolved);
5505 	if (err)
5506 		goto done;
5507 
5508 	err = delete_histedit_refs(worktree, repo);
5509 done:
5510 	if (fileindex)
5511 		got_fileindex_free(fileindex);
5512 	free(new_head_commit_id);
5513 	unlockerr = lock_worktree(worktree, LOCK_SH);
5514 	if (unlockerr && err == NULL)
5515 		err = unlockerr;
5516 	return err;
5517 }
5518 
5519 const struct got_error *
5520 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
5521     struct got_object_id *commit_id, struct got_repository *repo)
5522 {
5523 	const struct got_error *err;
5524 	char *commit_ref_name;
5525 
5526 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
5527 	if (err)
5528 		return err;
5529 
5530 	err = store_commit_id(commit_ref_name, commit_id, repo);
5531 	if (err)
5532 		goto done;
5533 
5534 	err = delete_ref(commit_ref_name, repo);
5535 done:
5536 	free(commit_ref_name);
5537 	return err;
5538 }
5539 
5540 struct check_stage_ok_arg {
5541 	struct got_object_id *head_commit_id;
5542 	struct got_worktree *worktree;
5543 	struct got_fileindex *fileindex;
5544 	struct got_repository *repo;
5545 	int have_changes;
5546 };
5547 
5548 const struct got_error *
5549 check_stage_ok(void *arg, unsigned char status,
5550     unsigned char staged_status, const char *relpath,
5551     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5552     struct got_object_id *commit_id)
5553 {
5554 	struct check_stage_ok_arg *a = arg;
5555 	const struct got_error *err = NULL;
5556 	struct got_fileindex_entry *ie;
5557 	struct got_object_id base_commit_id;
5558 	struct got_object_id *base_commit_idp = NULL;
5559 	char *in_repo_path = NULL, *p;
5560 
5561 	if (status == GOT_STATUS_UNVERSIONED)
5562 		return NULL;
5563 
5564 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
5565 	if (ie == NULL)
5566 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
5567 
5568 	if (asprintf(&in_repo_path, "%s%s%s", a->worktree->path_prefix,
5569 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
5570 	    relpath) == -1)
5571 		return got_error_from_errno("asprintf");
5572 
5573 	if (got_fileindex_entry_has_commit(ie)) {
5574 		memcpy(base_commit_id.sha1, ie->commit_sha1,
5575 		    SHA1_DIGEST_LENGTH);
5576 		base_commit_idp = &base_commit_id;
5577 	}
5578 
5579 	if (status == GOT_STATUS_NO_CHANGE) {
5580 		err = got_error_path(ie->path, GOT_ERR_STAGE_NO_CHANGE);
5581 		goto done;
5582 	} else if (status == GOT_STATUS_CONFLICT) {
5583 		err = got_error_path(ie->path, GOT_ERR_STAGE_CONFLICT);
5584 		goto done;
5585 	} else if (status != GOT_STATUS_ADD &&
5586 	    status != GOT_STATUS_MODIFY &&
5587 	    status != GOT_STATUS_DELETE) {
5588 		err = got_error_path(ie->path, GOT_ERR_FILE_STATUS);
5589 		goto done;
5590 	}
5591 
5592 	a->have_changes = 1;
5593 
5594 	p = in_repo_path;
5595 	while (p[0] == '/')
5596 		p++;
5597 	err = check_out_of_date(p, status, staged_status,
5598 	    blob_id, base_commit_idp, a->head_commit_id, a->repo,
5599 	    GOT_ERR_STAGE_OUT_OF_DATE);
5600 done:
5601 	free(in_repo_path);
5602 	return err;
5603 }
5604 
5605 struct stage_path_arg {
5606 	struct got_worktree *worktree;
5607 	struct got_fileindex *fileindex;
5608 	struct got_repository *repo;
5609 	got_worktree_status_cb status_cb;
5610 	void *status_arg;
5611 	got_worktree_patch_cb patch_cb;
5612 	void *patch_arg;
5613 };
5614 
5615 static const struct got_error *
5616 stage_path(void *arg, unsigned char status,
5617     unsigned char staged_status, const char *relpath,
5618     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5619     struct got_object_id *commit_id)
5620 {
5621 	struct stage_path_arg *a = arg;
5622 	const struct got_error *err = NULL;
5623 	struct got_fileindex_entry *ie;
5624 	char *ondisk_path = NULL, *path_content = NULL;
5625 	uint32_t stage;
5626 	struct got_object_id *new_staged_blob_id = NULL;
5627 
5628 	if (status == GOT_STATUS_UNVERSIONED)
5629 		return NULL;
5630 
5631 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
5632 	if (ie == NULL)
5633 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
5634 
5635 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
5636 	    relpath)== -1)
5637 		return got_error_from_errno("asprintf");
5638 
5639 	switch (status) {
5640 	case GOT_STATUS_ADD:
5641 	case GOT_STATUS_MODIFY:
5642 		if (a->patch_cb) {
5643 			if (status == GOT_STATUS_ADD) {
5644 				int choice = GOT_PATCH_CHOICE_NONE;
5645 				err = (*a->patch_cb)(&choice, a->patch_arg,
5646 				    status, ie->path, NULL, 1, 1);
5647 				if (err)
5648 					break;
5649 				if (choice != GOT_PATCH_CHOICE_YES)
5650 					break;
5651 			} else {
5652 				err = create_patched_content(&path_content, 0,
5653 				    staged_blob_id ? staged_blob_id : blob_id,
5654 				    ondisk_path, ie->path, a->repo,
5655 				    a->patch_cb, a->patch_arg);
5656 				if (err || path_content == NULL)
5657 					break;
5658 			}
5659 		}
5660 		err = got_object_blob_create(&new_staged_blob_id,
5661 		    path_content ? path_content : ondisk_path, a->repo);
5662 		if (err)
5663 			break;
5664 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
5665 		    SHA1_DIGEST_LENGTH);
5666 		if (status == GOT_STATUS_ADD || staged_status == GOT_STATUS_ADD)
5667 			stage = GOT_FILEIDX_STAGE_ADD;
5668 		else
5669 			stage = GOT_FILEIDX_STAGE_MODIFY;
5670 		got_fileindex_entry_stage_set(ie, stage);
5671 		if (a->status_cb == NULL)
5672 			break;
5673 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
5674 		    get_staged_status(ie), relpath, blob_id,
5675 		    new_staged_blob_id, NULL);
5676 		break;
5677 	case GOT_STATUS_DELETE:
5678 		if (staged_status == GOT_STATUS_DELETE)
5679 			break;
5680 		if (a->patch_cb) {
5681 			int choice = GOT_PATCH_CHOICE_NONE;
5682 			err = (*a->patch_cb)(&choice, a->patch_arg, status,
5683 			    ie->path, NULL, 1, 1);
5684 			if (err)
5685 				break;
5686 			if (choice == GOT_PATCH_CHOICE_NO)
5687 				break;
5688 			if (choice != GOT_PATCH_CHOICE_YES) {
5689 				err = got_error(GOT_ERR_PATCH_CHOICE);
5690 				break;
5691 			}
5692 		}
5693 		stage = GOT_FILEIDX_STAGE_DELETE;
5694 		got_fileindex_entry_stage_set(ie, stage);
5695 		if (a->status_cb == NULL)
5696 			break;
5697 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
5698 		    get_staged_status(ie), relpath, NULL, NULL, NULL);
5699 		break;
5700 	case GOT_STATUS_NO_CHANGE:
5701 		err = got_error_path(relpath, GOT_ERR_STAGE_NO_CHANGE);
5702 		break;
5703 	case GOT_STATUS_CONFLICT:
5704 		err = got_error_path(relpath, GOT_ERR_STAGE_CONFLICT);
5705 		break;
5706 	default:
5707 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
5708 		break;
5709 	}
5710 
5711 	if (path_content && unlink(path_content) == -1 && err == NULL)
5712 		err = got_error_from_errno2("unlink", path_content);
5713 	free(path_content);
5714 	free(ondisk_path);
5715 	free(new_staged_blob_id);
5716 	return err;
5717 }
5718 
5719 const struct got_error *
5720 got_worktree_stage(struct got_worktree *worktree,
5721     struct got_pathlist_head *paths,
5722     got_worktree_status_cb status_cb, void *status_arg,
5723     got_worktree_patch_cb patch_cb, void *patch_arg,
5724     struct got_repository *repo)
5725 {
5726 	const struct got_error *err = NULL, *sync_err, *unlockerr;
5727 	struct got_pathlist_entry *pe;
5728 	struct got_fileindex *fileindex = NULL;
5729 	char *fileindex_path = NULL;
5730 	struct got_reference *head_ref = NULL;
5731 	struct got_object_id *head_commit_id = NULL;
5732 	struct check_stage_ok_arg oka;
5733 	struct stage_path_arg spa;
5734 
5735 	err = lock_worktree(worktree, LOCK_EX);
5736 	if (err)
5737 		return err;
5738 
5739 	err = got_ref_open(&head_ref, repo,
5740 	    got_worktree_get_head_ref_name(worktree), 0);
5741 	if (err)
5742 		goto done;
5743 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
5744 	if (err)
5745 		goto done;
5746 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
5747 	if (err)
5748 		goto done;
5749 
5750 	/* Check pre-conditions before staging anything. */
5751 	oka.head_commit_id = head_commit_id;
5752 	oka.worktree = worktree;
5753 	oka.fileindex = fileindex;
5754 	oka.repo = repo;
5755 	oka.have_changes = 0;
5756 	TAILQ_FOREACH(pe, paths, entry) {
5757 		err = worktree_status(worktree, pe->path, fileindex, repo,
5758 		    check_stage_ok, &oka, NULL, NULL);
5759 		if (err)
5760 			goto done;
5761 	}
5762 	if (!oka.have_changes) {
5763 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
5764 		goto done;
5765 	}
5766 
5767 	spa.worktree = worktree;
5768 	spa.fileindex = fileindex;
5769 	spa.repo = repo;
5770 	spa.patch_cb = patch_cb;
5771 	spa.patch_arg = patch_arg;
5772 	spa.status_cb = status_cb;
5773 	spa.status_arg = status_arg;
5774 	TAILQ_FOREACH(pe, paths, entry) {
5775 		err = worktree_status(worktree, pe->path, fileindex, repo,
5776 		    stage_path, &spa, NULL, NULL);
5777 		if (err)
5778 			goto done;
5779 	}
5780 
5781 	sync_err = sync_fileindex(fileindex, fileindex_path);
5782 	if (sync_err && err == NULL)
5783 		err = sync_err;
5784 done:
5785 	if (head_ref)
5786 		got_ref_close(head_ref);
5787 	free(head_commit_id);
5788 	free(fileindex_path);
5789 	if (fileindex)
5790 		got_fileindex_free(fileindex);
5791 	unlockerr = lock_worktree(worktree, LOCK_SH);
5792 	if (unlockerr && err == NULL)
5793 		err = unlockerr;
5794 	return err;
5795 }
5796 
5797 struct unstage_path_arg {
5798 	struct got_worktree *worktree;
5799 	struct got_fileindex *fileindex;
5800 	struct got_repository *repo;
5801 	got_worktree_checkout_cb progress_cb;
5802 	void *progress_arg;
5803 	got_worktree_patch_cb patch_cb;
5804 	void *patch_arg;
5805 };
5806 
5807 static const struct got_error *
5808 create_unstaged_content(char **path_unstaged_content,
5809     char **path_new_staged_content, struct got_object_id *blob_id,
5810     struct got_object_id *staged_blob_id, const char *relpath,
5811     struct got_repository *repo,
5812     got_worktree_patch_cb patch_cb, void *patch_arg)
5813 {
5814 	const struct got_error *err;
5815 	struct got_blob_object *blob = NULL, *staged_blob = NULL;
5816 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL, *rejectfile = NULL;
5817 	char *path1 = NULL, *path2 = NULL, *label1 = NULL;
5818 	struct stat sb1, sb2;
5819 	struct got_diff_changes *changes = NULL;
5820 	struct got_diff_state *ds = NULL;
5821 	struct got_diff_args *args = NULL;
5822 	struct got_diff_change *change;
5823 	int diff_flags = 0, line_cur1 = 1, line_cur2 = 1, n = 0;
5824 	int have_content = 0, have_rejected_content = 0;
5825 
5826 	*path_unstaged_content = NULL;
5827 	*path_new_staged_content = NULL;
5828 
5829 	err = got_object_id_str(&label1, blob_id);
5830 	if (err)
5831 		return err;
5832 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192);
5833 	if (err)
5834 		goto done;
5835 
5836 	err = got_opentemp_named(&path1, &f1, "got-unstage-blob-base");
5837 	if (err)
5838 		goto done;
5839 
5840 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
5841 	if (err)
5842 		goto done;
5843 
5844 	err = got_object_open_as_blob(&staged_blob, repo, staged_blob_id, 8192);
5845 	if (err)
5846 		goto done;
5847 
5848 	err = got_opentemp_named(&path2, &f2, "got-unstage-blob-staged");
5849 	if (err)
5850 		goto done;
5851 
5852 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f2, staged_blob);
5853 	if (err)
5854 		goto done;
5855 
5856 	if (stat(path1, &sb1) == -1) {
5857 		err = got_error_from_errno2("stat", path1);
5858 		goto done;
5859 	}
5860 
5861 	if (stat(path2, &sb2) == -1) {
5862 		err = got_error_from_errno2("stat", path2);
5863 		goto done;
5864 	}
5865 
5866 	err = got_diff_files(&changes, &ds, &args, &diff_flags,
5867 	    f1, sb1.st_size, label1, f2, sb2.st_size, path2, 3, NULL);
5868 	if (err)
5869 		goto done;
5870 
5871 	err = got_opentemp_named(path_unstaged_content, &outfile,
5872 	    "got-unstaged-content");
5873 	if (err)
5874 		goto done;
5875 	err = got_opentemp_named(path_new_staged_content, &rejectfile,
5876 	    "got-new-staged-content");
5877 	if (err)
5878 		goto done;
5879 
5880 	if (fseek(f1, 0L, SEEK_SET) == -1) {
5881 		err = got_ferror(f1, GOT_ERR_IO);
5882 		goto done;
5883 	}
5884 	if (fseek(f2, 0L, SEEK_SET) == -1) {
5885 		err = got_ferror(f2, GOT_ERR_IO);
5886 		goto done;
5887 	}
5888 	SIMPLEQ_FOREACH(change, &changes->entries, entry) {
5889 		int choice;
5890 		err = apply_or_reject_change(&choice, change, ++n,
5891 		    changes->nchanges, ds, args, diff_flags, relpath,
5892 		    f1, f2, &line_cur1, &line_cur2,
5893 		    outfile, rejectfile, patch_cb, patch_arg);
5894 		if (err)
5895 			goto done;
5896 		if (choice == GOT_PATCH_CHOICE_YES)
5897 			have_content = 1;
5898 		else
5899 			have_rejected_content = 1;
5900 		if (choice == GOT_PATCH_CHOICE_QUIT)
5901 			break;
5902 	}
5903 	if (have_content || have_rejected_content)
5904 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
5905 		    outfile, rejectfile);
5906 done:
5907 	free(label1);
5908 	if (blob)
5909 		got_object_blob_close(blob);
5910 	if (staged_blob)
5911 		got_object_blob_close(staged_blob);
5912 	if (f1 && fclose(f1) == EOF && err == NULL)
5913 		err = got_error_from_errno2("fclose", path1);
5914 	if (f2 && fclose(f2) == EOF && err == NULL)
5915 		err = got_error_from_errno2("fclose", path2);
5916 	if (outfile && fclose(outfile) == EOF && err == NULL)
5917 		err = got_error_from_errno2("fclose", *path_unstaged_content);
5918 	if (rejectfile && fclose(rejectfile) == EOF && err == NULL)
5919 		err = got_error_from_errno2("fclose", *path_new_staged_content);
5920 	if (path1 && unlink(path1) == -1 && err == NULL)
5921 		err = got_error_from_errno2("unlink", path1);
5922 	if (path2 && unlink(path2) == -1 && err == NULL)
5923 		err = got_error_from_errno2("unlink", path2);
5924 	if (err || !have_content) {
5925 		if (*path_unstaged_content &&
5926 		    unlink(*path_unstaged_content) == -1 && err == NULL)
5927 			err = got_error_from_errno2("unlink",
5928 			    *path_unstaged_content);
5929 		free(*path_unstaged_content);
5930 		*path_unstaged_content = NULL;
5931 	}
5932 	if (err || !have_rejected_content) {
5933 		if (*path_new_staged_content &&
5934 		    unlink(*path_new_staged_content) == -1 && err == NULL)
5935 			err = got_error_from_errno2("unlink",
5936 			    *path_new_staged_content);
5937 		free(*path_new_staged_content);
5938 		*path_new_staged_content = NULL;
5939 	}
5940 	free(args);
5941 	if (ds) {
5942 		got_diff_state_free(ds);
5943 		free(ds);
5944 	}
5945 	if (changes)
5946 		got_diff_free_changes(changes);
5947 	free(path1);
5948 	free(path2);
5949 	return err;
5950 }
5951 
5952 static const struct got_error *
5953 unstage_path(void *arg, unsigned char status,
5954     unsigned char staged_status, const char *relpath,
5955     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5956     struct got_object_id *commit_id)
5957 {
5958 	const struct got_error *err = NULL;
5959 	struct unstage_path_arg *a = arg;
5960 	struct got_fileindex_entry *ie;
5961 	struct got_blob_object *blob_base = NULL, *blob_staged = NULL;
5962 	char *ondisk_path = NULL, *path_unstaged_content = NULL;
5963 	char *path_new_staged_content = NULL;
5964 	int local_changes_subsumed;
5965 	struct stat sb;
5966 
5967 	if (staged_status != GOT_STATUS_ADD &&
5968 	    staged_status != GOT_STATUS_MODIFY &&
5969 	    staged_status != GOT_STATUS_DELETE)
5970 		return NULL;
5971 
5972 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
5973 	if (ie == NULL)
5974 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
5975 
5976 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, relpath)
5977 	    == -1)
5978 		return got_error_from_errno("asprintf");
5979 
5980 	switch (staged_status) {
5981 	case GOT_STATUS_MODIFY:
5982 		err = got_object_open_as_blob(&blob_base, a->repo,
5983 		    blob_id, 8192);
5984 		if (err)
5985 			break;
5986 		/* fall through */
5987 	case GOT_STATUS_ADD:
5988 		if (a->patch_cb) {
5989 			if (staged_status == GOT_STATUS_ADD) {
5990 				int choice = GOT_PATCH_CHOICE_NONE;
5991 				err = (*a->patch_cb)(&choice, a->patch_arg,
5992 				    staged_status, ie->path, NULL, 1, 1);
5993 				if (err)
5994 					break;
5995 				if (choice != GOT_PATCH_CHOICE_YES)
5996 					break;
5997 			} else {
5998 				err = create_unstaged_content(
5999 				    &path_unstaged_content,
6000 				    &path_new_staged_content, blob_id,
6001 				    staged_blob_id, ie->path, a->repo,
6002 				    a->patch_cb, a->patch_arg);
6003 				if (err || path_unstaged_content == NULL)
6004 					break;
6005 				if (path_new_staged_content) {
6006 					err = got_object_blob_create(
6007 					    &staged_blob_id,
6008 					    path_new_staged_content,
6009 					    a->repo);
6010 					if (err)
6011 						break;
6012 					memcpy(ie->staged_blob_sha1,
6013 					    staged_blob_id->sha1,
6014 					    SHA1_DIGEST_LENGTH);
6015 				}
6016 				err = merge_file(&local_changes_subsumed,
6017 				    a->worktree, blob_base, ondisk_path,
6018 				    relpath, got_fileindex_perms_to_st(ie),
6019 				    path_unstaged_content, "unstaged",
6020 				    a->repo, a->progress_cb, a->progress_arg);
6021 				if (err == NULL &&
6022 				    path_new_staged_content == NULL)
6023 					got_fileindex_entry_stage_set(ie,
6024 					    GOT_FILEIDX_STAGE_NONE);
6025 				break; /* Done with this file. */
6026 			}
6027 		}
6028 		err = got_object_open_as_blob(&blob_staged, a->repo,
6029 		    staged_blob_id, 8192);
6030 		if (err)
6031 			break;
6032 		err = merge_blob(&local_changes_subsumed, a->worktree,
6033 		    blob_base, ondisk_path, relpath,
6034 		    got_fileindex_perms_to_st(ie), blob_staged,
6035 		    commit_id ? commit_id : a->worktree->base_commit_id,
6036 		    a->repo, a->progress_cb, a->progress_arg);
6037 		if (err == NULL)
6038 			got_fileindex_entry_stage_set(ie,
6039 			    GOT_FILEIDX_STAGE_NONE);
6040 		break;
6041 	case GOT_STATUS_DELETE:
6042 		if (a->patch_cb) {
6043 			int choice = GOT_PATCH_CHOICE_NONE;
6044 			err = (*a->patch_cb)(&choice, a->patch_arg,
6045 			    staged_status, ie->path, NULL, 1, 1);
6046 			if (err)
6047 				break;
6048 			if (choice == GOT_PATCH_CHOICE_NO)
6049 				break;
6050 			if (choice != GOT_PATCH_CHOICE_YES) {
6051 				err = got_error(GOT_ERR_PATCH_CHOICE);
6052 				break;
6053 			}
6054 		}
6055 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
6056 		err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
6057 		if (err)
6058 			break;
6059 		err = (*a->progress_cb)(a->progress_arg, status, relpath);
6060 		break;
6061 	}
6062 
6063 	free(ondisk_path);
6064 	if (path_unstaged_content &&
6065 	    unlink(path_unstaged_content) == -1 && err == NULL)
6066 		err = got_error_from_errno2("unlink", path_unstaged_content);
6067 	if (path_new_staged_content &&
6068 	    unlink(path_new_staged_content) == -1 && err == NULL)
6069 		err = got_error_from_errno2("unlink", path_new_staged_content);
6070 	free(path_unstaged_content);
6071 	free(path_new_staged_content);
6072 	if (blob_base)
6073 		got_object_blob_close(blob_base);
6074 	if (blob_staged)
6075 		got_object_blob_close(blob_staged);
6076 	return err;
6077 }
6078 
6079 const struct got_error *
6080 got_worktree_unstage(struct got_worktree *worktree,
6081     struct got_pathlist_head *paths,
6082     got_worktree_checkout_cb progress_cb, void *progress_arg,
6083     got_worktree_patch_cb patch_cb, void *patch_arg,
6084     struct got_repository *repo)
6085 {
6086 	const struct got_error *err = NULL, *sync_err, *unlockerr;
6087 	struct got_pathlist_entry *pe;
6088 	struct got_fileindex *fileindex = NULL;
6089 	char *fileindex_path = NULL;
6090 	struct unstage_path_arg upa;
6091 
6092 	err = lock_worktree(worktree, LOCK_EX);
6093 	if (err)
6094 		return err;
6095 
6096 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
6097 	if (err)
6098 		goto done;
6099 
6100 	upa.worktree = worktree;
6101 	upa.fileindex = fileindex;
6102 	upa.repo = repo;
6103 	upa.progress_cb = progress_cb;
6104 	upa.progress_arg = progress_arg;
6105 	upa.patch_cb = patch_cb;
6106 	upa.patch_arg = patch_arg;
6107 	TAILQ_FOREACH(pe, paths, entry) {
6108 		err = worktree_status(worktree, pe->path, fileindex, repo,
6109 		    unstage_path, &upa, NULL, NULL);
6110 		if (err)
6111 			goto done;
6112 	}
6113 
6114 	sync_err = sync_fileindex(fileindex, fileindex_path);
6115 	if (sync_err && err == NULL)
6116 		err = sync_err;
6117 done:
6118 	free(fileindex_path);
6119 	if (fileindex)
6120 		got_fileindex_free(fileindex);
6121 	unlockerr = lock_worktree(worktree, LOCK_SH);
6122 	if (unlockerr && err == NULL)
6123 		err = unlockerr;
6124 	return err;
6125 }