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 <time.h>
28 #include <fcntl.h>
29 #include <errno.h>
30 #include <unistd.h>
31 #include <sha1.h>
32 #include <zlib.h>
33 #include <fnmatch.h>
34 #include <libgen.h>
35 #include <uuid.h>
36 #include <util.h>
37 
38 #include "got_error.h"
39 #include "got_repository.h"
40 #include "got_reference.h"
41 #include "got_object.h"
42 #include "got_path.h"
43 #include "got_cancel.h"
44 #include "got_worktree.h"
45 #include "got_opentemp.h"
46 #include "got_diff.h"
47 
48 #include "got_lib_worktree.h"
49 #include "got_lib_sha1.h"
50 #include "got_lib_fileindex.h"
51 #include "got_lib_inflate.h"
52 #include "got_lib_delta.h"
53 #include "got_lib_object.h"
54 #include "got_lib_object_parse.h"
55 #include "got_lib_object_create.h"
56 #include "got_lib_object_idset.h"
57 #include "got_lib_diff.h"
58 
59 #ifndef MIN
60 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
61 #endif
62 
63 static const struct got_error *
64 create_meta_file(const char *path_got, const char *name, const char *content)
65 {
66 	const struct got_error *err = NULL;
67 	char *path;
68 
69 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
70 		return got_error_from_errno("asprintf");
71 
72 	err = got_path_create_file(path, content);
73 	free(path);
74 	return err;
75 }
76 
77 static const struct got_error *
78 update_meta_file(const char *path_got, const char *name, const char *content)
79 {
80 	const struct got_error *err = NULL;
81 	FILE *tmpfile = NULL;
82 	char *tmppath = NULL;
83 	char *path = NULL;
84 
85 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
86 		err = got_error_from_errno("asprintf");
87 		path = NULL;
88 		goto done;
89 	}
90 
91 	err = got_opentemp_named(&tmppath, &tmpfile, path);
92 	if (err)
93 		goto done;
94 
95 	if (content) {
96 		int len = fprintf(tmpfile, "%s\n", content);
97 		if (len != strlen(content) + 1) {
98 			err = got_error_from_errno2("fprintf", tmppath);
99 			goto done;
100 		}
101 	}
102 
103 	if (rename(tmppath, path) != 0) {
104 		err = got_error_from_errno3("rename", tmppath, path);
105 		unlink(tmppath);
106 		goto done;
107 	}
108 
109 done:
110 	if (fclose(tmpfile) != 0 && err == NULL)
111 		err = got_error_from_errno2("fclose", tmppath);
112 	free(tmppath);
113 	return err;
114 }
115 
116 static const struct got_error *
117 read_meta_file(char **content, const char *path_got, const char *name)
118 {
119 	const struct got_error *err = NULL;
120 	char *path;
121 	int fd = -1;
122 	ssize_t n;
123 	struct stat sb;
124 
125 	*content = NULL;
126 
127 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
128 		err = got_error_from_errno("asprintf");
129 		path = NULL;
130 		goto done;
131 	}
132 
133 	fd = open(path, O_RDONLY | O_NOFOLLOW);
134 	if (fd == -1) {
135 		if (errno == ENOENT)
136 			err = got_error_path(path, GOT_ERR_WORKTREE_META);
137 		else
138 			err = got_error_from_errno2("open", path);
139 		goto done;
140 	}
141 	if (flock(fd, LOCK_SH | LOCK_NB) == -1) {
142 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
143 		    : got_error_from_errno2("flock", path));
144 		goto done;
145 	}
146 
147 	if (fstat(fd, &sb) != 0) {
148 		err = got_error_from_errno2("fstat", path);
149 		goto done;
150 	}
151 	*content = calloc(1, sb.st_size);
152 	if (*content == NULL) {
153 		err = got_error_from_errno("calloc");
154 		goto done;
155 	}
156 
157 	n = read(fd, *content, sb.st_size);
158 	if (n != sb.st_size) {
159 		err = (n == -1 ? got_error_from_errno2("read", path) :
160 		    got_error_path(path, GOT_ERR_WORKTREE_META));
161 		goto done;
162 	}
163 	if ((*content)[sb.st_size - 1] != '\n') {
164 		err = got_error_path(path, GOT_ERR_WORKTREE_META);
165 		goto done;
166 	}
167 	(*content)[sb.st_size - 1] = '\0';
168 
169 done:
170 	if (fd != -1 && close(fd) == -1 && err == NULL)
171 		err = got_error_from_errno2("close", path_got);
172 	free(path);
173 	if (err) {
174 		free(*content);
175 		*content = NULL;
176 	}
177 	return err;
178 }
179 
180 static const struct got_error *
181 write_head_ref(const char *path_got, struct got_reference *head_ref)
182 {
183 	const struct got_error *err = NULL;
184 	char *refstr = NULL;
185 
186 	if (got_ref_is_symbolic(head_ref)) {
187 		refstr = got_ref_to_str(head_ref);
188 		if (refstr == NULL)
189 			return got_error_from_errno("got_ref_to_str");
190 	} else {
191 		refstr = strdup(got_ref_get_name(head_ref));
192 		if (refstr == NULL)
193 			return got_error_from_errno("strdup");
194 	}
195 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
196 	free(refstr);
197 	return err;
198 }
199 
200 const struct got_error *
201 got_worktree_init(const char *path, struct got_reference *head_ref,
202     const char *prefix, struct got_repository *repo)
203 {
204 	const struct got_error *err = NULL;
205 	struct got_object_id *commit_id = NULL;
206 	uuid_t uuid;
207 	uint32_t uuid_status;
208 	int obj_type;
209 	char *path_got = NULL;
210 	char *formatstr = NULL;
211 	char *absprefix = NULL;
212 	char *basestr = NULL;
213 	char *uuidstr = NULL;
214 
215 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
216 		err = got_error(GOT_ERR_WORKTREE_REPO);
217 		goto done;
218 	}
219 
220 	err = got_ref_resolve(&commit_id, repo, head_ref);
221 	if (err)
222 		return err;
223 	err = got_object_get_type(&obj_type, repo, commit_id);
224 	if (err)
225 		return err;
226 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
227 		return got_error(GOT_ERR_OBJ_TYPE);
228 
229 	if (!got_path_is_absolute(prefix)) {
230 		if (asprintf(&absprefix, "/%s", prefix) == -1)
231 			return got_error_from_errno("asprintf");
232 	}
233 
234 	/* Create top-level directory (may already exist). */
235 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
236 		err = got_error_from_errno2("mkdir", path);
237 		goto done;
238 	}
239 
240 	/* Create .got directory (may already exist). */
241 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
242 		err = got_error_from_errno("asprintf");
243 		goto done;
244 	}
245 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
246 		err = got_error_from_errno2("mkdir", path_got);
247 		goto done;
248 	}
249 
250 	/* Create an empty lock file. */
251 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
252 	if (err)
253 		goto done;
254 
255 	/* Create an empty file index. */
256 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
257 	if (err)
258 		goto done;
259 
260 	/* Write the HEAD reference. */
261 	err = write_head_ref(path_got, head_ref);
262 	if (err)
263 		goto done;
264 
265 	/* Record our base commit. */
266 	err = got_object_id_str(&basestr, commit_id);
267 	if (err)
268 		goto done;
269 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
270 	if (err)
271 		goto done;
272 
273 	/* Store path to repository. */
274 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
275 	    got_repo_get_path(repo));
276 	if (err)
277 		goto done;
278 
279 	/* Store in-repository path prefix. */
280 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
281 	    absprefix ? absprefix : prefix);
282 	if (err)
283 		goto done;
284 
285 	/* Generate UUID. */
286 	uuid_create(&uuid, &uuid_status);
287 	if (uuid_status != uuid_s_ok) {
288 		err = got_error_uuid(uuid_status, "uuid_create");
289 		goto done;
290 	}
291 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
292 	if (uuid_status != uuid_s_ok) {
293 		err = got_error_uuid(uuid_status, "uuid_to_string");
294 		goto done;
295 	}
296 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
297 	if (err)
298 		goto done;
299 
300 	/* Stamp work tree with format file. */
301 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
302 		err = got_error_from_errno("asprintf");
303 		goto done;
304 	}
305 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
306 	if (err)
307 		goto done;
308 
309 done:
310 	free(commit_id);
311 	free(path_got);
312 	free(formatstr);
313 	free(absprefix);
314 	free(basestr);
315 	free(uuidstr);
316 	return err;
317 }
318 
319 static const struct got_error *
320 open_worktree(struct got_worktree **worktree, const char *path)
321 {
322 	const struct got_error *err = NULL;
323 	char *path_got;
324 	char *formatstr = NULL;
325 	char *uuidstr = NULL;
326 	char *path_lock = NULL;
327 	char *base_commit_id_str = NULL;
328 	int version, fd = -1;
329 	const char *errstr;
330 	struct got_repository *repo = NULL;
331 	uint32_t uuid_status;
332 
333 	*worktree = NULL;
334 
335 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
336 		err = got_error_from_errno("asprintf");
337 		path_got = NULL;
338 		goto done;
339 	}
340 
341 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
342 		err = got_error_from_errno("asprintf");
343 		path_lock = NULL;
344 		goto done;
345 	}
346 
347 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
348 	if (fd == -1) {
349 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
350 		    : got_error_from_errno2("open", path_lock));
351 		goto done;
352 	}
353 
354 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
355 	if (err)
356 		goto done;
357 
358 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
359 	if (errstr) {
360 		err = got_error_msg(GOT_ERR_WORKTREE_META,
361 		    "could not parse work tree format version number");
362 		goto done;
363 	}
364 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
365 		err = got_error(GOT_ERR_WORKTREE_VERS);
366 		goto done;
367 	}
368 
369 	*worktree = calloc(1, sizeof(**worktree));
370 	if (*worktree == NULL) {
371 		err = got_error_from_errno("calloc");
372 		goto done;
373 	}
374 	(*worktree)->lockfd = -1;
375 
376 	(*worktree)->root_path = strdup(path);
377 	if ((*worktree)->root_path == NULL) {
378 		err = got_error_from_errno("strdup");
379 		goto done;
380 	}
381 	err = read_meta_file(&(*worktree)->repo_path, path_got,
382 	    GOT_WORKTREE_REPOSITORY);
383 	if (err)
384 		goto done;
385 
386 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
387 	    GOT_WORKTREE_PATH_PREFIX);
388 	if (err)
389 		goto done;
390 
391 	err = read_meta_file(&base_commit_id_str, path_got,
392 	    GOT_WORKTREE_BASE_COMMIT);
393 	if (err)
394 		goto done;
395 
396 	err = read_meta_file(&uuidstr, path_got, GOT_WORKTREE_UUID);
397 	if (err)
398 		goto done;
399 	uuid_from_string(uuidstr, &(*worktree)->uuid, &uuid_status);
400 	if (uuid_status != uuid_s_ok) {
401 		err = got_error_uuid(uuid_status, "uuid_from_string");
402 		goto done;
403 	}
404 
405 	err = got_repo_open(&repo, (*worktree)->repo_path, NULL);
406 	if (err)
407 		goto done;
408 
409 	err = got_object_resolve_id_str(&(*worktree)->base_commit_id, repo,
410 	    base_commit_id_str);
411 	if (err)
412 		goto done;
413 
414 	err = read_meta_file(&(*worktree)->head_ref_name, path_got,
415 	    GOT_WORKTREE_HEAD_REF);
416 done:
417 	if (repo)
418 		got_repo_close(repo);
419 	free(path_got);
420 	free(path_lock);
421 	free(base_commit_id_str);
422 	free(uuidstr);
423 	free(formatstr);
424 	if (err) {
425 		if (fd != -1)
426 			close(fd);
427 		if (*worktree != NULL)
428 			got_worktree_close(*worktree);
429 		*worktree = NULL;
430 	} else
431 		(*worktree)->lockfd = fd;
432 
433 	return err;
434 }
435 
436 const struct got_error *
437 got_worktree_open(struct got_worktree **worktree, const char *path)
438 {
439 	const struct got_error *err = NULL;
440 
441 	do {
442 		err = open_worktree(worktree, path);
443 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT))
444 			return err;
445 		if (*worktree)
446 			return NULL;
447 		path = dirname(path);
448 		if (path == NULL)
449 			return got_error_from_errno2("dirname", path);
450 	} while (!((path[0] == '.' || path[0] == '/') && path[1] == '\0'));
451 
452 	return got_error(GOT_ERR_NOT_WORKTREE);
453 }
454 
455 const struct got_error *
456 got_worktree_close(struct got_worktree *worktree)
457 {
458 	const struct got_error *err = NULL;
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->root_path);
468 	free(worktree);
469 	return err;
470 }
471 
472 const char *
473 got_worktree_get_root_path(struct got_worktree *worktree)
474 {
475 	return worktree->root_path;
476 }
477 
478 const char *
479 got_worktree_get_repo_path(struct got_worktree *worktree)
480 {
481 	return worktree->repo_path;
482 }
483 
484 const char *
485 got_worktree_get_path_prefix(struct got_worktree *worktree)
486 {
487 	return worktree->path_prefix;
488 }
489 
490 const struct got_error *
491 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
492     const char *path_prefix)
493 {
494 	char *absprefix = NULL;
495 
496 	if (!got_path_is_absolute(path_prefix)) {
497 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
498 			return got_error_from_errno("asprintf");
499 	}
500 	*match = (strcmp(absprefix ? absprefix : path_prefix,
501 	    worktree->path_prefix) == 0);
502 	free(absprefix);
503 	return NULL;
504 }
505 
506 const char *
507 got_worktree_get_head_ref_name(struct got_worktree *worktree)
508 {
509 	return worktree->head_ref_name;
510 }
511 
512 const struct got_error *
513 got_worktree_set_head_ref(struct got_worktree *worktree,
514     struct got_reference *head_ref)
515 {
516 	const struct got_error *err = NULL;
517 	char *path_got = NULL, *head_ref_name = NULL;
518 
519 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
520 	    GOT_WORKTREE_GOT_DIR) == -1) {
521 		err = got_error_from_errno("asprintf");
522 		path_got = NULL;
523 		goto done;
524 	}
525 
526 	head_ref_name = strdup(got_ref_get_name(head_ref));
527 	if (head_ref_name == NULL) {
528 		err = got_error_from_errno("strdup");
529 		goto done;
530 	}
531 
532 	err = write_head_ref(path_got, head_ref);
533 	if (err)
534 		goto done;
535 
536 	free(worktree->head_ref_name);
537 	worktree->head_ref_name = head_ref_name;
538 done:
539 	free(path_got);
540 	if (err)
541 		free(head_ref_name);
542 	return err;
543 }
544 
545 struct got_object_id *
546 got_worktree_get_base_commit_id(struct got_worktree *worktree)
547 {
548 	return worktree->base_commit_id;
549 }
550 
551 const struct got_error *
552 got_worktree_set_base_commit_id(struct got_worktree *worktree,
553     struct got_repository *repo, struct got_object_id *commit_id)
554 {
555 	const struct got_error *err;
556 	struct got_object *obj = NULL;
557 	char *id_str = NULL;
558 	char *path_got = NULL;
559 
560 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
561 	    GOT_WORKTREE_GOT_DIR) == -1) {
562 		err = got_error_from_errno("asprintf");
563 		path_got = NULL;
564 		goto done;
565 	}
566 
567 	err = got_object_open(&obj, repo, commit_id);
568 	if (err)
569 		return err;
570 
571 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
572 		err = got_error(GOT_ERR_OBJ_TYPE);
573 		goto done;
574 	}
575 
576 	/* Record our base commit. */
577 	err = got_object_id_str(&id_str, commit_id);
578 	if (err)
579 		goto done;
580 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
581 	if (err)
582 		goto done;
583 
584 	free(worktree->base_commit_id);
585 	worktree->base_commit_id = got_object_id_dup(commit_id);
586 	if (worktree->base_commit_id == NULL) {
587 		err = got_error_from_errno("got_object_id_dup");
588 		goto done;
589 	}
590 done:
591 	if (obj)
592 		got_object_close(obj);
593 	free(id_str);
594 	free(path_got);
595 	return err;
596 }
597 
598 static const struct got_error *
599 lock_worktree(struct got_worktree *worktree, int operation)
600 {
601 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
602 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
603 		    : got_error_from_errno2("flock",
604 		    got_worktree_get_root_path(worktree)));
605 	return NULL;
606 }
607 
608 static const struct got_error *
609 add_dir_on_disk(struct got_worktree *worktree, const char *path)
610 {
611 	const struct got_error *err = NULL;
612 	char *abspath;
613 
614 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
615 		return got_error_from_errno("asprintf");
616 
617 	err = got_path_mkdir(abspath);
618 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
619 		struct stat sb;
620 		err = NULL;
621 		if (lstat(abspath, &sb) == -1) {
622 			err = got_error_from_errno2("lstat", abspath);
623 		} else if (!S_ISDIR(sb.st_mode)) {
624 			/* TODO directory is obstructed; do something */
625 			err = got_error(GOT_ERR_FILE_OBSTRUCTED);
626 		}
627 	}
628 	free(abspath);
629 	return err;
630 }
631 
632 static const struct got_error *
633 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
634 {
635 	const struct got_error *err = NULL;
636 	uint8_t fbuf1[8192];
637 	uint8_t fbuf2[8192];
638 	size_t flen1 = 0, flen2 = 0;
639 
640 	*same = 1;
641 
642 	for (;;) {
643 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
644 		if (flen1 == 0 && ferror(f1)) {
645 			err = got_error_from_errno("fread");
646 			break;
647 		}
648 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
649 		if (flen2 == 0 && ferror(f2)) {
650 			err = got_error_from_errno("fread");
651 			break;
652 		}
653 		if (flen1 == 0) {
654 			if (flen2 != 0)
655 				*same = 0;
656 			break;
657 		} else if (flen2 == 0) {
658 			if (flen1 != 0)
659 				*same = 0;
660 			break;
661 		} else if (flen1 == flen2) {
662 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
663 				*same = 0;
664 				break;
665 			}
666 		} else {
667 			*same = 0;
668 			break;
669 		}
670 	}
671 
672 	return err;
673 }
674 
675 static const struct got_error *
676 check_files_equal(int *same, const char *f1_path, const char *f2_path)
677 {
678 	const struct got_error *err = NULL;
679 	struct stat sb;
680 	size_t size1, size2;
681 	FILE *f1 = NULL, *f2 = NULL;
682 
683 	*same = 1;
684 
685 	if (lstat(f1_path, &sb) != 0) {
686 		err = got_error_from_errno2("lstat", f1_path);
687 		goto done;
688 	}
689 	size1 = sb.st_size;
690 
691 	if (lstat(f2_path, &sb) != 0) {
692 		err = got_error_from_errno2("lstat", f2_path);
693 		goto done;
694 	}
695 	size2 = sb.st_size;
696 
697 	if (size1 != size2) {
698 		*same = 0;
699 		return NULL;
700 	}
701 
702 	f1 = fopen(f1_path, "r");
703 	if (f1 == NULL)
704 		return got_error_from_errno2("open", f1_path);
705 
706 	f2 = fopen(f2_path, "r");
707 	if (f2 == NULL) {
708 		err = got_error_from_errno2("open", f2_path);
709 		goto done;
710 	}
711 
712 	err = check_file_contents_equal(same, f1, f2);
713 done:
714 	if (f1 && fclose(f1) != 0 && err == NULL)
715 		err = got_error_from_errno("fclose");
716 	if (f2 && fclose(f2) != 0 && err == NULL)
717 		err = got_error_from_errno("fclose");
718 
719 	return err;
720 }
721 
722 /*
723  * Perform a 3-way merge where blob_orig acts as the common ancestor,
724  * the file at deriv_path acts as the first derived version, and the
725  * file on disk acts as the second derived version.
726  */
727 static const struct got_error *
728 merge_file(int *local_changes_subsumed, struct got_worktree *worktree,
729     struct got_blob_object *blob_orig, const char *ondisk_path,
730     const char *path, uint16_t st_mode, const char *deriv_path,
731     const char *label_deriv, struct got_repository *repo,
732     got_worktree_checkout_cb progress_cb, void *progress_arg)
733 {
734 	const struct got_error *err = NULL;
735 	int merged_fd = -1;
736 	FILE *f_orig = NULL;
737 	char *blob_orig_path = NULL;
738 	char *merged_path = NULL, *base_path = NULL;
739 	int overlapcnt = 0;
740 	char *parent;
741 
742 	*local_changes_subsumed = 0;
743 
744 	parent = dirname(ondisk_path);
745 	if (parent == NULL)
746 		return got_error_from_errno2("dirname", ondisk_path);
747 
748 	if (asprintf(&base_path, "%s/got-merged", parent) == -1)
749 		return got_error_from_errno("asprintf");
750 
751 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
752 	if (err)
753 		goto done;
754 
755 	free(base_path);
756 	if (asprintf(&base_path, "%s/got-merge-blob-orig", parent) == -1) {
757 		err = got_error_from_errno("asprintf");
758 		base_path = NULL;
759 		goto done;
760 	}
761 
762 	err = got_opentemp_named(&blob_orig_path, &f_orig, base_path);
763 	if (err)
764 		goto done;
765 	if (blob_orig) {
766 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
767 		    blob_orig);
768 		if (err)
769 			goto done;
770 	} else {
771 		/*
772 		 * If the file has no blob, this is an "add vs add" conflict,
773 		 * and we simply use an empty ancestor file to make both files
774 		 * appear in the merged result in their entirety.
775 		 */
776 	}
777 
778 	err = got_merge_diff3(&overlapcnt, merged_fd, deriv_path,
779 	    blob_orig_path, ondisk_path, label_deriv, path);
780 	if (err)
781 		goto done;
782 
783 	err = (*progress_cb)(progress_arg,
784 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
785 	if (err)
786 		goto done;
787 
788 	if (fsync(merged_fd) != 0) {
789 		err = got_error_from_errno("fsync");
790 		goto done;
791 	}
792 
793 	/* Check if a clean merge has subsumed all local changes. */
794 	if (overlapcnt == 0) {
795 		err = check_files_equal(local_changes_subsumed, deriv_path,
796 		    merged_path);
797 		if (err)
798 			goto done;
799 	}
800 
801 	if (chmod(merged_path, st_mode) != 0) {
802 		err = got_error_from_errno2("chmod", merged_path);
803 		goto done;
804 	}
805 
806 	if (rename(merged_path, ondisk_path) != 0) {
807 		err = got_error_from_errno3("rename", merged_path,
808 		    ondisk_path);
809 		unlink(merged_path);
810 		goto done;
811 	}
812 
813 done:
814 	if (merged_fd != -1 && close(merged_fd) != 0 && err == NULL)
815 		err = got_error_from_errno("close");
816 	if (f_orig && fclose(f_orig) != 0 && err == NULL)
817 		err = got_error_from_errno("fclose");
818 	free(merged_path);
819 	free(base_path);
820 	if (blob_orig_path) {
821 		unlink(blob_orig_path);
822 		free(blob_orig_path);
823 	}
824 	return err;
825 }
826 
827 /*
828  * Perform a 3-way merge where blob_orig acts as the common ancestor,
829  * blob_deriv acts as the first derived version, and the file on disk
830  * acts as the second derived version.
831  */
832 static const struct got_error *
833 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
834     struct got_blob_object *blob_orig, const char *ondisk_path,
835     const char *path, uint16_t st_mode, struct got_blob_object *blob_deriv,
836     struct got_object_id *deriv_base_commit_id,
837     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
838     void *progress_arg)
839 {
840 	const struct got_error *err = NULL;
841 	FILE *f_deriv = NULL;
842 	char *blob_deriv_path = NULL, *base_path = NULL, *id_str = NULL;
843 	char *label_deriv = NULL, *parent;
844 
845 	*local_changes_subsumed = 0;
846 
847 	parent = dirname(ondisk_path);
848 	if (parent == NULL)
849 		return got_error_from_errno2("dirname", ondisk_path);
850 
851 	free(base_path);
852 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
853 		err = got_error_from_errno("asprintf");
854 		base_path = NULL;
855 		goto done;
856 	}
857 
858 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path);
859 	if (err)
860 		goto done;
861 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
862 	    blob_deriv);
863 	if (err)
864 		goto done;
865 
866 	err = got_object_id_str(&id_str, deriv_base_commit_id);
867 	if (err)
868 		goto done;
869 	if (asprintf(&label_deriv, "commit %s", id_str) == -1) {
870 		err = got_error_from_errno("asprintf");
871 		goto done;
872 	}
873 
874 	err = merge_file(local_changes_subsumed, worktree, blob_orig,
875 	    ondisk_path, path, st_mode, blob_deriv_path, label_deriv,
876 	    repo, progress_cb, progress_arg);
877 done:
878 	if (f_deriv && fclose(f_deriv) != 0 && err == NULL)
879 		err = got_error_from_errno("fclose");
880 	free(base_path);
881 	if (blob_deriv_path) {
882 		unlink(blob_deriv_path);
883 		free(blob_deriv_path);
884 	}
885 	free(id_str);
886 	free(label_deriv);
887 	return err;
888 }
889 
890 static const struct got_error *
891 update_blob_fileindex_entry(struct got_worktree *worktree,
892     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
893     const char *ondisk_path, const char *path, struct got_blob_object *blob,
894     int update_timestamps)
895 {
896 	const struct got_error *err = NULL;
897 
898 	if (ie == NULL)
899 		ie = got_fileindex_entry_get(fileindex, path, strlen(path));
900 	if (ie)
901 		err = got_fileindex_entry_update(ie, ondisk_path,
902 		    blob->id.sha1, worktree->base_commit_id->sha1,
903 		    update_timestamps);
904 	else {
905 		struct got_fileindex_entry *new_ie;
906 		err = got_fileindex_entry_alloc(&new_ie, ondisk_path,
907 		    path, blob->id.sha1, worktree->base_commit_id->sha1);
908 		if (!err)
909 			err = got_fileindex_entry_add(fileindex, new_ie);
910 	}
911 	return err;
912 }
913 
914 static const struct got_error *
915 install_blob(struct got_worktree *worktree, const char *ondisk_path,
916     const char *path, uint16_t te_mode, uint16_t st_mode,
917     struct got_blob_object *blob, int restoring_missing_file,
918     int reverting_versioned_file, struct got_repository *repo,
919     got_worktree_checkout_cb progress_cb, void *progress_arg)
920 {
921 	const struct got_error *err = NULL;
922 	int fd = -1;
923 	size_t len, hdrlen;
924 	int update = 0;
925 	char *tmppath = NULL;
926 
927 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
928 	    GOT_DEFAULT_FILE_MODE);
929 	if (fd == -1) {
930 		if (errno == ENOENT) {
931 			char *parent = dirname(path);
932 			if (parent == NULL)
933 				return got_error_from_errno2("dirname", path);
934 			err = add_dir_on_disk(worktree, parent);
935 			if (err)
936 				return err;
937 			fd = open(ondisk_path,
938 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
939 			    GOT_DEFAULT_FILE_MODE);
940 			if (fd == -1)
941 				return got_error_from_errno2("open",
942 				    ondisk_path);
943 		} else if (errno == EEXIST) {
944 			if (!S_ISREG(st_mode)) {
945 				/* TODO file is obstructed; do something */
946 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
947 				goto done;
948 			} else {
949 				err = got_opentemp_named_fd(&tmppath, &fd,
950 				    ondisk_path);
951 				if (err)
952 					goto done;
953 				update = 1;
954 			}
955 		} else
956 			return got_error_from_errno2("open", ondisk_path);
957 	}
958 
959 	if (restoring_missing_file)
960 		err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING, path);
961 	else if (reverting_versioned_file)
962 		err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT, path);
963 	else
964 		err = (*progress_cb)(progress_arg,
965 		    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
966 	if (err)
967 		goto done;
968 
969 	hdrlen = got_object_blob_get_hdrlen(blob);
970 	do {
971 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
972 		err = got_object_blob_read_block(&len, blob);
973 		if (err)
974 			break;
975 		if (len > 0) {
976 			/* Skip blob object header first time around. */
977 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
978 			if (outlen == -1) {
979 				err = got_error_from_errno("write");
980 				goto done;
981 			} else if (outlen != len - hdrlen) {
982 				err = got_error(GOT_ERR_IO);
983 				goto done;
984 			}
985 			hdrlen = 0;
986 		}
987 	} while (len != 0);
988 
989 	if (fsync(fd) != 0) {
990 		err = got_error_from_errno("fsync");
991 		goto done;
992 	}
993 
994 	if (update) {
995 		if (rename(tmppath, ondisk_path) != 0) {
996 			err = got_error_from_errno3("rename", tmppath,
997 			    ondisk_path);
998 			unlink(tmppath);
999 			goto done;
1000 		}
1001 	}
1002 
1003 	if (te_mode & S_IXUSR) {
1004 		if (chmod(ondisk_path, st_mode | S_IXUSR) == -1) {
1005 			err = got_error_from_errno2("chmod", ondisk_path);
1006 			goto done;
1007 		}
1008 	} else {
1009 		if (chmod(ondisk_path, st_mode & ~S_IXUSR) == -1) {
1010 			err = got_error_from_errno2("chmod", ondisk_path);
1011 			goto done;
1012 		}
1013 	}
1014 
1015 done:
1016 	if (fd != -1 && close(fd) != 0 && err == NULL)
1017 		err = got_error_from_errno("close");
1018 	free(tmppath);
1019 	return err;
1020 }
1021 
1022 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
1023 static const struct got_error *
1024 get_modified_file_content_status(unsigned char *status, FILE *f)
1025 {
1026 	const struct got_error *err = NULL;
1027 	const char *markers[3] = {
1028 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
1029 		GOT_DIFF_CONFLICT_MARKER_SEP,
1030 		GOT_DIFF_CONFLICT_MARKER_END
1031 	};
1032 	int i = 0;
1033 	char *line;
1034 	size_t len;
1035 	const char delim[3] = {'\0', '\0', '\0'};
1036 
1037 	while (*status == GOT_STATUS_MODIFY) {
1038 		line = fparseln(f, &len, NULL, delim, 0);
1039 		if (line == NULL) {
1040 			if (feof(f))
1041 				break;
1042 			err = got_ferror(f, GOT_ERR_IO);
1043 			break;
1044 		}
1045 
1046 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1047 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1048 			    == 0)
1049 				*status = GOT_STATUS_CONFLICT;
1050 			else
1051 				i++;
1052 		}
1053 	}
1054 
1055 	return err;
1056 }
1057 
1058 static int
1059 stat_info_differs(struct got_fileindex_entry *ie, struct stat *sb)
1060 {
1061 	return !(ie->ctime_sec == sb->st_ctime &&
1062 	    ie->ctime_nsec == sb->st_ctimensec &&
1063 	    ie->mtime_sec == sb->st_mtime &&
1064 	    ie->mtime_nsec == sb->st_mtimensec &&
1065 	    ie->size == (sb->st_size & 0xffffffff));
1066 }
1067 
1068 static unsigned char
1069 get_staged_status(struct got_fileindex_entry *ie)
1070 {
1071 	switch (got_fileindex_entry_stage_get(ie)) {
1072 	case GOT_FILEIDX_STAGE_ADD:
1073 		return GOT_STATUS_ADD;
1074 	case GOT_FILEIDX_STAGE_DELETE:
1075 		return GOT_STATUS_DELETE;
1076 	case GOT_FILEIDX_STAGE_MODIFY:
1077 		return GOT_STATUS_MODIFY;
1078 	default:
1079 		return GOT_STATUS_NO_CHANGE;
1080 	}
1081 }
1082 
1083 static const struct got_error *
1084 get_file_status(unsigned char *status, struct stat *sb,
1085     struct got_fileindex_entry *ie, const char *abspath,
1086     struct got_repository *repo)
1087 {
1088 	const struct got_error *err = NULL;
1089 	struct got_object_id id;
1090 	size_t hdrlen;
1091 	FILE *f = NULL;
1092 	uint8_t fbuf[8192];
1093 	struct got_blob_object *blob = NULL;
1094 	size_t flen, blen;
1095 	unsigned char staged_status = get_staged_status(ie);
1096 
1097 	*status = GOT_STATUS_NO_CHANGE;
1098 
1099 	if (lstat(abspath, sb) == -1) {
1100 		if (errno == ENOENT) {
1101 			if (got_fileindex_entry_has_file_on_disk(ie))
1102 				*status = GOT_STATUS_MISSING;
1103 			else
1104 				*status = GOT_STATUS_DELETE;
1105 			return NULL;
1106 		}
1107 		return got_error_from_errno2("lstat", abspath);
1108 	}
1109 
1110 	if (!S_ISREG(sb->st_mode)) {
1111 		*status = GOT_STATUS_OBSTRUCTED;
1112 		return NULL;
1113 	}
1114 
1115 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1116 		*status = GOT_STATUS_DELETE;
1117 		return NULL;
1118 	} else if (!got_fileindex_entry_has_blob(ie) &&
1119 	    staged_status != GOT_STATUS_ADD) {
1120 		*status = GOT_STATUS_ADD;
1121 		return NULL;
1122 	}
1123 
1124 	if (!stat_info_differs(ie, sb))
1125 		return NULL;
1126 
1127 	if (staged_status == GOT_STATUS_MODIFY ||
1128 	    staged_status == GOT_STATUS_ADD)
1129 		memcpy(id.sha1, ie->staged_blob_sha1, sizeof(id.sha1));
1130 	else
1131 		memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1132 
1133 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1134 	if (err)
1135 		return err;
1136 
1137 	f = fopen(abspath, "r");
1138 	if (f == NULL) {
1139 		err = got_error_from_errno2("fopen", abspath);
1140 		goto done;
1141 	}
1142 	hdrlen = got_object_blob_get_hdrlen(blob);
1143 	for (;;) {
1144 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1145 		err = got_object_blob_read_block(&blen, blob);
1146 		if (err)
1147 			goto done;
1148 		/* Skip length of blob object header first time around. */
1149 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1150 		if (flen == 0 && ferror(f)) {
1151 			err = got_error_from_errno("fread");
1152 			goto done;
1153 		}
1154 		if (blen == 0) {
1155 			if (flen != 0)
1156 				*status = GOT_STATUS_MODIFY;
1157 			break;
1158 		} else if (flen == 0) {
1159 			if (blen != 0)
1160 				*status = GOT_STATUS_MODIFY;
1161 			break;
1162 		} else if (blen - hdrlen == flen) {
1163 			/* Skip blob object header first time around. */
1164 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1165 				*status = GOT_STATUS_MODIFY;
1166 				break;
1167 			}
1168 		} else {
1169 			*status = GOT_STATUS_MODIFY;
1170 			break;
1171 		}
1172 		hdrlen = 0;
1173 	}
1174 
1175 	if (*status == GOT_STATUS_MODIFY) {
1176 		rewind(f);
1177 		err = get_modified_file_content_status(status, f);
1178 	}
1179 done:
1180 	if (blob)
1181 		got_object_blob_close(blob);
1182 	if (f)
1183 		fclose(f);
1184 	return err;
1185 }
1186 
1187 /*
1188  * Update timestamps in the file index if a file is unmodified and
1189  * we had to run a full content comparison to find out.
1190  */
1191 static const struct got_error *
1192 sync_timestamps(char *ondisk_path, unsigned char status,
1193     struct got_fileindex_entry *ie, struct stat *sb)
1194 {
1195 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1196 		return got_fileindex_entry_update(ie, ondisk_path,
1197 		    ie->blob_sha1, ie->commit_sha1, 1);
1198 
1199 	return NULL;
1200 }
1201 
1202 static const struct got_error *
1203 update_blob(struct got_worktree *worktree,
1204     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1205     struct got_tree_entry *te, const char *path,
1206     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1207     void *progress_arg)
1208 {
1209 	const struct got_error *err = NULL;
1210 	struct got_blob_object *blob = NULL;
1211 	char *ondisk_path;
1212 	unsigned char status = GOT_STATUS_NO_CHANGE;
1213 	struct stat sb;
1214 
1215 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1216 		return got_error_from_errno("asprintf");
1217 
1218 	if (ie) {
1219 		if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE) {
1220 			err = got_error_path(ie->path, GOT_ERR_FILE_STAGED);
1221 			goto done;
1222 		}
1223 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1224 		if (err)
1225 			goto done;
1226 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1227 			sb.st_mode = got_fileindex_perms_to_st(ie);
1228 	} else
1229 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
1230 
1231 	if (status == GOT_STATUS_OBSTRUCTED) {
1232 		err = (*progress_cb)(progress_arg, status, path);
1233 		goto done;
1234 	}
1235 
1236 	if (ie && status != GOT_STATUS_MISSING) {
1237 		if (got_fileindex_entry_has_commit(ie) &&
1238 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1239 		    SHA1_DIGEST_LENGTH) == 0) {
1240 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1241 			if (err)
1242 				goto done;
1243 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1244 			    path);
1245 			goto done;
1246 		}
1247 		if (got_fileindex_entry_has_blob(ie) &&
1248 		    memcmp(ie->blob_sha1, te->id->sha1,
1249 		    SHA1_DIGEST_LENGTH) == 0) {
1250 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1251 			goto done;
1252 		}
1253 	}
1254 
1255 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1256 	if (err)
1257 		goto done;
1258 
1259 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1260 		int update_timestamps;
1261 		struct got_blob_object *blob2 = NULL;
1262 		if (got_fileindex_entry_has_blob(ie)) {
1263 			struct got_object_id id2;
1264 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1265 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
1266 			if (err)
1267 				goto done;
1268 		}
1269 		err = merge_blob(&update_timestamps, worktree, blob2,
1270 		    ondisk_path, path, sb.st_mode, blob,
1271 		    worktree->base_commit_id, repo,
1272 		    progress_cb, progress_arg);
1273 		if (blob2)
1274 			got_object_blob_close(blob2);
1275 		if (err)
1276 			goto done;
1277 		/*
1278 		 * Do not update timestamps of files with local changes.
1279 		 * Otherwise, a future status walk would treat them as
1280 		 * unmodified files again.
1281 		 */
1282 		err = got_fileindex_entry_update(ie, ondisk_path,
1283 		    blob->id.sha1, worktree->base_commit_id->sha1,
1284 		    update_timestamps);
1285 	} else if (status == GOT_STATUS_DELETE) {
1286 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1287 		if (err)
1288 			goto done;
1289 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1290 		    ondisk_path, path, blob, 0);
1291 		if (err)
1292 			goto done;
1293 	} else {
1294 		err = install_blob(worktree, ondisk_path, path, te->mode,
1295 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1296 		    repo, progress_cb, progress_arg);
1297 		if (err)
1298 			goto done;
1299 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1300 		    ondisk_path, path, blob, 1);
1301 		if (err)
1302 			goto done;
1303 	}
1304 	got_object_blob_close(blob);
1305 done:
1306 	free(ondisk_path);
1307 	return err;
1308 }
1309 
1310 static const struct got_error *
1311 remove_ondisk_file(const char *root_path, const char *path)
1312 {
1313 	const struct got_error *err = NULL;
1314 	char *ondisk_path = NULL;
1315 
1316 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1317 		return got_error_from_errno("asprintf");
1318 
1319 	if (unlink(ondisk_path) == -1) {
1320 		if (errno != ENOENT)
1321 			err = got_error_from_errno2("unlink", ondisk_path);
1322 	} else {
1323 		char *parent = dirname(ondisk_path);
1324 		while (parent && strcmp(parent, root_path) != 0) {
1325 			if (rmdir(parent) == -1) {
1326 				if (errno != ENOTEMPTY)
1327 					err = got_error_from_errno2("rmdir",
1328 					    parent);
1329 				break;
1330 			}
1331 			parent = dirname(parent);
1332 		}
1333 	}
1334 	free(ondisk_path);
1335 	return err;
1336 }
1337 
1338 static const struct got_error *
1339 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1340     struct got_fileindex_entry *ie, struct got_repository *repo,
1341     got_worktree_checkout_cb progress_cb, void *progress_arg)
1342 {
1343 	const struct got_error *err = NULL;
1344 	unsigned char status;
1345 	struct stat sb;
1346 	char *ondisk_path;
1347 
1348 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
1349 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
1350 
1351 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1352 	    == -1)
1353 		return got_error_from_errno("asprintf");
1354 
1355 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1356 	if (err)
1357 		return err;
1358 
1359 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1360 	    status == GOT_STATUS_ADD) {
1361 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1362 		if (err)
1363 			return err;
1364 		/*
1365 		 * Preserve the working file and change the deleted blob's
1366 		 * entry into a schedule-add entry.
1367 		 */
1368 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1369 		    0);
1370 		if (err)
1371 			return err;
1372 	} else {
1373 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1374 		if (err)
1375 			return err;
1376 		if (status == GOT_STATUS_NO_CHANGE) {
1377 			err = remove_ondisk_file(worktree->root_path, ie->path);
1378 			if (err)
1379 				return err;
1380 		}
1381 		got_fileindex_entry_remove(fileindex, ie);
1382 	}
1383 
1384 	return err;
1385 }
1386 
1387 struct diff_cb_arg {
1388     struct got_fileindex *fileindex;
1389     struct got_worktree *worktree;
1390     struct got_repository *repo;
1391     got_worktree_checkout_cb progress_cb;
1392     void *progress_arg;
1393     got_cancel_cb cancel_cb;
1394     void *cancel_arg;
1395 };
1396 
1397 static const struct got_error *
1398 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1399     struct got_tree_entry *te, const char *parent_path)
1400 {
1401 	struct diff_cb_arg *a = arg;
1402 
1403 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1404 		return got_error(GOT_ERR_CANCELLED);
1405 
1406 	return update_blob(a->worktree, a->fileindex, ie, te,
1407 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1408 }
1409 
1410 static const struct got_error *
1411 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1412 {
1413 	struct diff_cb_arg *a = arg;
1414 
1415 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1416 		return got_error(GOT_ERR_CANCELLED);
1417 
1418 	return delete_blob(a->worktree, a->fileindex, ie,
1419 	    a->repo, a->progress_cb, a->progress_arg);
1420 }
1421 
1422 static const struct got_error *
1423 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1424 {
1425 	struct diff_cb_arg *a = arg;
1426 	const struct got_error *err;
1427 	char *path;
1428 
1429 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1430 		return got_error(GOT_ERR_CANCELLED);
1431 
1432 	if (got_object_tree_entry_is_submodule(te))
1433 		return NULL;
1434 
1435 	if (asprintf(&path, "%s%s%s", parent_path,
1436 	    parent_path[0] ? "/" : "", te->name)
1437 	    == -1)
1438 		return got_error_from_errno("asprintf");
1439 
1440 	if (S_ISDIR(te->mode))
1441 		err = add_dir_on_disk(a->worktree, path);
1442 	else
1443 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1444 		    a->repo, a->progress_cb, a->progress_arg);
1445 
1446 	free(path);
1447 	return err;
1448 }
1449 
1450 static const struct got_error *
1451 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
1452 {
1453 	const struct got_error *err = NULL;
1454 	char *uuidstr = NULL;
1455 	uint32_t uuid_status;
1456 
1457 	*refname = NULL;
1458 
1459 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1460 	if (uuid_status != uuid_s_ok)
1461 		return got_error_uuid(uuid_status, "uuid_to_string");
1462 
1463 	if (asprintf(refname, "%s-%s", prefix, uuidstr)
1464 	    == -1) {
1465 		err = got_error_from_errno("asprintf");
1466 		*refname = NULL;
1467 	}
1468 	free(uuidstr);
1469 	return err;
1470 }
1471 
1472 const struct got_error *
1473 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1474 {
1475 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
1476 }
1477 
1478 static const struct got_error *
1479 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
1480 {
1481 	return get_ref_name(refname, worktree,
1482 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
1483 }
1484 
1485 static const struct got_error *
1486 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
1487 {
1488 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
1489 }
1490 
1491 static const struct got_error *
1492 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
1493 {
1494 	return get_ref_name(refname, worktree,
1495 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
1496 }
1497 
1498 static const struct got_error *
1499 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
1500 {
1501 	return get_ref_name(refname, worktree,
1502 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
1503 }
1504 
1505 static const struct got_error *
1506 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
1507 {
1508 	return get_ref_name(refname, worktree,
1509 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
1510 }
1511 
1512 static const struct got_error *
1513 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
1514 {
1515 	return get_ref_name(refname, worktree,
1516 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
1517 }
1518 
1519 static const struct got_error *
1520 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
1521 {
1522 	return get_ref_name(refname, worktree,
1523 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
1524 }
1525 
1526 static const struct got_error *
1527 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
1528 {
1529 	return get_ref_name(refname, worktree,
1530 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
1531 }
1532 
1533 const struct got_error *
1534 got_worktree_get_histedit_script_path(char **path,
1535     struct got_worktree *worktree)
1536 {
1537 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
1538 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
1539 		*path = NULL;
1540 		return got_error_from_errno("asprintf");
1541 	}
1542 	return NULL;
1543 }
1544 
1545 /*
1546  * Prevent Git's garbage collector from deleting our base commit by
1547  * setting a reference to our base commit's ID.
1548  */
1549 static const struct got_error *
1550 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1551 {
1552 	const struct got_error *err = NULL;
1553 	struct got_reference *ref = NULL;
1554 	char *refname;
1555 
1556 	err = got_worktree_get_base_ref_name(&refname, worktree);
1557 	if (err)
1558 		return err;
1559 
1560 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1561 	if (err)
1562 		goto done;
1563 
1564 	err = got_ref_write(ref, repo);
1565 done:
1566 	free(refname);
1567 	if (ref)
1568 		got_ref_close(ref);
1569 	return err;
1570 }
1571 
1572 static const struct got_error *
1573 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
1574 {
1575 	const struct got_error *err = NULL;
1576 
1577 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1578 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1579 		err = got_error_from_errno("asprintf");
1580 		*fileindex_path = NULL;
1581 	}
1582 	return err;
1583 }
1584 
1585 
1586 static const struct got_error *
1587 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1588     struct got_worktree *worktree)
1589 {
1590 	const struct got_error *err = NULL;
1591 	FILE *index = NULL;
1592 
1593 	*fileindex_path = NULL;
1594 	*fileindex = got_fileindex_alloc();
1595 	if (*fileindex == NULL)
1596 		return got_error_from_errno("got_fileindex_alloc");
1597 
1598 	err = get_fileindex_path(fileindex_path, worktree);
1599 	if (err)
1600 		goto done;
1601 
1602 	index = fopen(*fileindex_path, "rb");
1603 	if (index == NULL) {
1604 		if (errno != ENOENT)
1605 			err = got_error_from_errno2("fopen", *fileindex_path);
1606 	} else {
1607 		err = got_fileindex_read(*fileindex, index);
1608 		if (fclose(index) != 0 && err == NULL)
1609 			err = got_error_from_errno("fclose");
1610 	}
1611 done:
1612 	if (err) {
1613 		free(*fileindex_path);
1614 		*fileindex_path = NULL;
1615 		got_fileindex_free(*fileindex);
1616 		*fileindex = NULL;
1617 	}
1618 	return err;
1619 }
1620 
1621 struct bump_base_commit_id_arg {
1622 	struct got_object_id *base_commit_id;
1623 	const char *path;
1624 	size_t path_len;
1625 	const char *entry_name;
1626 	got_worktree_checkout_cb progress_cb;
1627 	void *progress_arg;
1628 };
1629 
1630 /* Bump base commit ID of all files within an updated part of the work tree. */
1631 static const struct got_error *
1632 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
1633 {
1634 	const struct got_error *err;
1635 	struct bump_base_commit_id_arg *a = arg;
1636 
1637 	if (a->entry_name) {
1638 		if (strcmp(ie->path, a->path) != 0)
1639 			return NULL;
1640 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
1641 		return NULL;
1642 
1643 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
1644 	    SHA1_DIGEST_LENGTH) == 0)
1645 		return NULL;
1646 
1647 	if (a->progress_cb) {
1648 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
1649 		    ie->path);
1650 		if (err)
1651 			return err;
1652 	}
1653 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
1654 	return NULL;
1655 }
1656 
1657 static const struct got_error *
1658 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
1659 {
1660 	const struct got_error *err = NULL;
1661 	char *new_fileindex_path = NULL;
1662 	FILE *new_index = NULL;
1663 
1664 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1665 	    fileindex_path);
1666 	if (err)
1667 		goto done;
1668 
1669 	err = got_fileindex_write(fileindex, new_index);
1670 	if (err)
1671 		goto done;
1672 
1673 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1674 		err = got_error_from_errno3("rename", new_fileindex_path,
1675 		    fileindex_path);
1676 		unlink(new_fileindex_path);
1677 	}
1678 done:
1679 	if (new_index)
1680 		fclose(new_index);
1681 	free(new_fileindex_path);
1682 	return err;
1683 }
1684 
1685 static const struct got_error *
1686 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
1687     struct got_object_id **tree_id, const char *wt_relpath,
1688     struct got_worktree *worktree, struct got_repository *repo)
1689 {
1690 	const struct got_error *err = NULL;
1691 	struct got_object_id *id = NULL;
1692 	char *in_repo_path = NULL;
1693 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
1694 
1695 	*entry_type = GOT_OBJ_TYPE_ANY;
1696 	*tree_relpath = NULL;
1697 	*tree_id = NULL;
1698 
1699 	if (wt_relpath[0] == '\0') {
1700 		/* Check out all files within the work tree. */
1701 		*entry_type = GOT_OBJ_TYPE_TREE;
1702 		*tree_relpath = strdup("");
1703 		if (*tree_relpath == NULL) {
1704 			err = got_error_from_errno("strdup");
1705 			goto done;
1706 		}
1707 		err = got_object_id_by_path(tree_id, repo,
1708 		    worktree->base_commit_id, worktree->path_prefix);
1709 		if (err)
1710 			goto done;
1711 		return NULL;
1712 	}
1713 
1714 	/* Check out a subset of files in the work tree. */
1715 
1716 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
1717 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
1718 		err = got_error_from_errno("asprintf");
1719 		goto done;
1720 	}
1721 
1722 	err = got_object_id_by_path(&id, repo, worktree->base_commit_id,
1723 	    in_repo_path);
1724 	if (err)
1725 		goto done;
1726 
1727 	free(in_repo_path);
1728 	in_repo_path = NULL;
1729 
1730 	err = got_object_get_type(entry_type, repo, id);
1731 	if (err)
1732 		goto done;
1733 
1734 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
1735 		/* Check out a single file. */
1736 		if (strchr(wt_relpath, '/')  == NULL) {
1737 			/* Check out a single file in work tree's root dir. */
1738 			in_repo_path = strdup(worktree->path_prefix);
1739 			if (in_repo_path == NULL) {
1740 				err = got_error_from_errno("strdup");
1741 				goto done;
1742 			}
1743 			*tree_relpath = strdup("");
1744 			if (*tree_relpath == NULL) {
1745 				err = got_error_from_errno("strdup");
1746 				goto done;
1747 			}
1748 		} else {
1749 			/* Check out a single file in a subdirectory. */
1750 			err = got_path_dirname(tree_relpath, wt_relpath);
1751 			if (err)
1752 				return err;
1753 			if (asprintf(&in_repo_path, "%s%s%s",
1754 			    worktree->path_prefix, is_root_wt ? "" : "/",
1755 			    *tree_relpath) == -1) {
1756 				err = got_error_from_errno("asprintf");
1757 				goto done;
1758 			}
1759 		}
1760 		err = got_object_id_by_path(tree_id, repo,
1761 		    worktree->base_commit_id, in_repo_path);
1762 	} else {
1763 		/* Check out all files within a subdirectory. */
1764 		*tree_id = got_object_id_dup(id);
1765 		if (*tree_id == NULL) {
1766 			err = got_error_from_errno("got_object_id_dup");
1767 			goto done;
1768 		}
1769 		*tree_relpath = strdup(wt_relpath);
1770 		if (*tree_relpath == NULL) {
1771 			err = got_error_from_errno("strdup");
1772 			goto done;
1773 		}
1774 	}
1775 done:
1776 	free(id);
1777 	free(in_repo_path);
1778 	if (err) {
1779 		*entry_type = GOT_OBJ_TYPE_ANY;
1780 		free(*tree_relpath);
1781 		*tree_relpath = NULL;
1782 		free(*tree_id);
1783 		*tree_id = NULL;
1784 	}
1785 	return err;
1786 }
1787 
1788 static const struct got_error *
1789 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
1790     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
1791     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1792     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
1793 {
1794 	const struct got_error *err = NULL;
1795 	struct got_commit_object *commit = NULL;
1796 	struct got_tree_object *tree = NULL;
1797 	struct got_fileindex_diff_tree_cb diff_cb;
1798 	struct diff_cb_arg arg;
1799 
1800 	err = ref_base_commit(worktree, repo);
1801 	if (err)
1802 		goto done;
1803 
1804 	err = got_object_open_as_commit(&commit, repo,
1805 	   worktree->base_commit_id);
1806 	if (err)
1807 		goto done;
1808 
1809 	err = got_object_open_as_tree(&tree, repo, tree_id);
1810 	if (err)
1811 		goto done;
1812 
1813 	if (entry_name &&
1814 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1815 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1816 		goto done;
1817 	}
1818 
1819 	diff_cb.diff_old_new = diff_old_new;
1820 	diff_cb.diff_old = diff_old;
1821 	diff_cb.diff_new = diff_new;
1822 	arg.fileindex = fileindex;
1823 	arg.worktree = worktree;
1824 	arg.repo = repo;
1825 	arg.progress_cb = progress_cb;
1826 	arg.progress_arg = progress_arg;
1827 	arg.cancel_cb = cancel_cb;
1828 	arg.cancel_arg = cancel_arg;
1829 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
1830 	    entry_name, repo, &diff_cb, &arg);
1831 done:
1832 	if (tree)
1833 		got_object_tree_close(tree);
1834 	if (commit)
1835 		got_object_commit_close(commit);
1836 	return err;
1837 }
1838 
1839 const struct got_error *
1840 got_worktree_checkout_files(struct got_worktree *worktree,
1841     struct got_pathlist_head *paths, struct got_repository *repo,
1842     got_worktree_checkout_cb progress_cb, void *progress_arg,
1843     got_cancel_cb cancel_cb, void *cancel_arg)
1844 {
1845 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1846 	struct got_commit_object *commit = NULL;
1847 	struct got_tree_object *tree = NULL;
1848 	struct got_fileindex *fileindex = NULL;
1849 	char *fileindex_path = NULL;
1850 	struct got_pathlist_entry *pe;
1851 	struct tree_path_data {
1852 		SIMPLEQ_ENTRY(tree_path_data) entry;
1853 		struct got_object_id *tree_id;
1854 		int entry_type;
1855 		char *relpath;
1856 		char *entry_name;
1857 	} *tpd = NULL;
1858 	SIMPLEQ_HEAD(tree_paths, tree_path_data) tree_paths;
1859 
1860 	SIMPLEQ_INIT(&tree_paths);
1861 
1862 	err = lock_worktree(worktree, LOCK_EX);
1863 	if (err)
1864 		return err;
1865 
1866 	/* Map all specified paths to in-repository trees. */
1867 	TAILQ_FOREACH(pe, paths, entry) {
1868 		tpd = malloc(sizeof(*tpd));
1869 		if (tpd == NULL) {
1870 			err = got_error_from_errno("malloc");
1871 			goto done;
1872 		}
1873 
1874 		err = find_tree_entry_for_checkout(&tpd->entry_type,
1875 		    &tpd->relpath, &tpd->tree_id, pe->path, worktree, repo);
1876 		if (err) {
1877 			free(tpd);
1878 			goto done;
1879 		}
1880 
1881 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
1882 			err = got_path_basename(&tpd->entry_name, pe->path);
1883 			if (err) {
1884 				free(tpd->relpath);
1885 				free(tpd->tree_id);
1886 				free(tpd);
1887 				goto done;
1888 			}
1889 		} else
1890 			tpd->entry_name = NULL;
1891 
1892 		SIMPLEQ_INSERT_TAIL(&tree_paths, tpd, entry);
1893 	}
1894 
1895 	/*
1896 	 * Read the file index.
1897 	 * Checking out files is supposed to be an idempotent operation.
1898 	 * If the on-disk file index is incomplete we will try to complete it.
1899 	 */
1900 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1901 	if (err)
1902 		goto done;
1903 
1904 	tpd = SIMPLEQ_FIRST(&tree_paths);
1905 	TAILQ_FOREACH(pe, paths, entry) {
1906 		struct bump_base_commit_id_arg bbc_arg;
1907 
1908 		err = checkout_files(worktree, fileindex, tpd->relpath,
1909 		    tpd->tree_id, tpd->entry_name, repo,
1910 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
1911 		if (err)
1912 			break;
1913 
1914 		bbc_arg.base_commit_id = worktree->base_commit_id;
1915 		bbc_arg.entry_name = tpd->entry_name;
1916 		bbc_arg.path = pe->path;
1917 		bbc_arg.path_len = pe->path_len;
1918 		bbc_arg.progress_cb = progress_cb;
1919 		bbc_arg.progress_arg = progress_arg;
1920 		err = got_fileindex_for_each_entry_safe(fileindex,
1921 		    bump_base_commit_id, &bbc_arg);
1922 		if (err)
1923 			break;
1924 
1925 		tpd = SIMPLEQ_NEXT(tpd, entry);
1926 	}
1927 	sync_err = sync_fileindex(fileindex, fileindex_path);
1928 	if (sync_err && err == NULL)
1929 		err = sync_err;
1930 done:
1931 	free(fileindex_path);
1932 	if (tree)
1933 		got_object_tree_close(tree);
1934 	if (commit)
1935 		got_object_commit_close(commit);
1936 	if (fileindex)
1937 		got_fileindex_free(fileindex);
1938 	while (!SIMPLEQ_EMPTY(&tree_paths)) {
1939 		tpd = SIMPLEQ_FIRST(&tree_paths);
1940 		SIMPLEQ_REMOVE_HEAD(&tree_paths, entry);
1941 		free(tpd->relpath);
1942 		free(tpd->tree_id);
1943 		free(tpd);
1944 	}
1945 	unlockerr = lock_worktree(worktree, LOCK_SH);
1946 	if (unlockerr && err == NULL)
1947 		err = unlockerr;
1948 	return err;
1949 }
1950 
1951 struct merge_file_cb_arg {
1952     struct got_worktree *worktree;
1953     struct got_fileindex *fileindex;
1954     got_worktree_checkout_cb progress_cb;
1955     void *progress_arg;
1956     got_cancel_cb cancel_cb;
1957     void *cancel_arg;
1958     struct got_object_id *commit_id2;
1959 };
1960 
1961 static const struct got_error *
1962 merge_file_cb(void *arg, struct got_blob_object *blob1,
1963     struct got_blob_object *blob2, struct got_object_id *id1,
1964     struct got_object_id *id2, const char *path1, const char *path2,
1965     struct got_repository *repo)
1966 {
1967 	static const struct got_error *err = NULL;
1968 	struct merge_file_cb_arg *a = arg;
1969 	struct got_fileindex_entry *ie;
1970 	char *ondisk_path = NULL;
1971 	struct stat sb;
1972 	unsigned char status;
1973 	int local_changes_subsumed;
1974 
1975 	if (blob1 && blob2) {
1976 		ie = got_fileindex_entry_get(a->fileindex, path2,
1977 		    strlen(path2));
1978 		if (ie == NULL)
1979 			return (*a->progress_cb)(a->progress_arg,
1980 			    GOT_STATUS_MISSING, path2);
1981 
1982 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1983 		    path2) == -1)
1984 			return got_error_from_errno("asprintf");
1985 
1986 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1987 		if (err)
1988 			goto done;
1989 
1990 		if (status == GOT_STATUS_DELETE) {
1991 			err = (*a->progress_cb)(a->progress_arg,
1992 			    GOT_STATUS_MERGE, path2);
1993 			goto done;
1994 		}
1995 		if (status != GOT_STATUS_NO_CHANGE &&
1996 		    status != GOT_STATUS_MODIFY &&
1997 		    status != GOT_STATUS_CONFLICT &&
1998 		    status != GOT_STATUS_ADD) {
1999 			err = (*a->progress_cb)(a->progress_arg, status, path2);
2000 			goto done;
2001 		}
2002 
2003 		err = merge_blob(&local_changes_subsumed, a->worktree, blob1,
2004 		    ondisk_path, path2, sb.st_mode, blob2, a->commit_id2, repo,
2005 		    a->progress_cb, a->progress_arg);
2006 	} else if (blob1) {
2007 		ie = got_fileindex_entry_get(a->fileindex, path1,
2008 		    strlen(path1));
2009 		if (ie == NULL)
2010 			return (*a->progress_cb)(a->progress_arg,
2011 			    GOT_STATUS_MISSING, path2);
2012 
2013 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2014 		    path1) == -1)
2015 			return got_error_from_errno("asprintf");
2016 
2017 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2018 		if (err)
2019 			goto done;
2020 
2021 		switch (status) {
2022 		case GOT_STATUS_NO_CHANGE:
2023 			err = (*a->progress_cb)(a->progress_arg,
2024 			    GOT_STATUS_DELETE, path1);
2025 			if (err)
2026 				goto done;
2027 			err = remove_ondisk_file(a->worktree->root_path, path1);
2028 			if (err)
2029 				goto done;
2030 			if (ie)
2031 				got_fileindex_entry_mark_deleted_from_disk(ie);
2032 			break;
2033 		case GOT_STATUS_DELETE:
2034 		case GOT_STATUS_MISSING:
2035 			err = (*a->progress_cb)(a->progress_arg,
2036 			    GOT_STATUS_DELETE, path1);
2037 			if (err)
2038 				goto done;
2039 			if (ie)
2040 				got_fileindex_entry_mark_deleted_from_disk(ie);
2041 			break;
2042 		case GOT_STATUS_ADD:
2043 		case GOT_STATUS_MODIFY:
2044 		case GOT_STATUS_CONFLICT:
2045 			err = (*a->progress_cb)(a->progress_arg,
2046 			    GOT_STATUS_CANNOT_DELETE, path1);
2047 			if (err)
2048 				goto done;
2049 			break;
2050 		case GOT_STATUS_OBSTRUCTED:
2051 			err = (*a->progress_cb)(a->progress_arg, status, path1);
2052 			if (err)
2053 				goto done;
2054 			break;
2055 		default:
2056 			break;
2057 		}
2058 	} else if (blob2) {
2059 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2060 		    path2) == -1)
2061 			return got_error_from_errno("asprintf");
2062 		ie = got_fileindex_entry_get(a->fileindex, path2,
2063 		    strlen(path2));
2064 		if (ie) {
2065 			err = get_file_status(&status, &sb, ie, ondisk_path,
2066 			    repo);
2067 			if (err)
2068 				goto done;
2069 			if (status != GOT_STATUS_NO_CHANGE &&
2070 			    status != GOT_STATUS_MODIFY &&
2071 			    status != GOT_STATUS_CONFLICT &&
2072 			    status != GOT_STATUS_ADD) {
2073 				err = (*a->progress_cb)(a->progress_arg,
2074 				    status, path2);
2075 				goto done;
2076 			}
2077 			err = merge_blob(&local_changes_subsumed, a->worktree,
2078 			    NULL, ondisk_path, path2, sb.st_mode, blob2,
2079 			    a->commit_id2, repo,
2080 			    a->progress_cb, a->progress_arg);
2081 			if (status == GOT_STATUS_DELETE) {
2082 				err = update_blob_fileindex_entry(a->worktree,
2083 				    a->fileindex, ie, ondisk_path, ie->path,
2084 				    blob2, 0);
2085 				if (err)
2086 					goto done;
2087 			}
2088 		} else {
2089 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
2090 			err = install_blob(a->worktree, ondisk_path, path2,
2091 			    /* XXX get this from parent tree! */
2092 			    GOT_DEFAULT_FILE_MODE,
2093 			    sb.st_mode, blob2, 0, 0, repo,
2094 			    a->progress_cb, a->progress_arg);
2095 			if (err)
2096 				goto done;
2097 			err = got_fileindex_entry_alloc(&ie,
2098 			    ondisk_path, path2, NULL, NULL);
2099 			if (err)
2100 				goto done;
2101 			err = got_fileindex_entry_add(a->fileindex, ie);
2102 			if (err) {
2103 				got_fileindex_entry_free(ie);
2104 				goto done;
2105 			}
2106 		}
2107 	}
2108 done:
2109 	free(ondisk_path);
2110 	return err;
2111 }
2112 
2113 struct check_merge_ok_arg {
2114 	struct got_worktree *worktree;
2115 	struct got_repository *repo;
2116 };
2117 
2118 static const struct got_error *
2119 check_merge_ok(void *arg, struct got_fileindex_entry *ie)
2120 {
2121 	const struct got_error *err = NULL;
2122 	struct check_merge_ok_arg *a = arg;
2123 	unsigned char status;
2124 	struct stat sb;
2125 	char *ondisk_path;
2126 
2127 	/* Reject merges into a work tree with mixed base commits. */
2128 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
2129 	    SHA1_DIGEST_LENGTH))
2130 		return got_error(GOT_ERR_MIXED_COMMITS);
2131 
2132 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
2133 	    == -1)
2134 		return got_error_from_errno("asprintf");
2135 
2136 	/* Reject merges into a work tree with conflicted files. */
2137 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
2138 	if (err)
2139 		return err;
2140 	if (status == GOT_STATUS_CONFLICT)
2141 		return got_error(GOT_ERR_CONFLICTS);
2142 
2143 	return NULL;
2144 }
2145 
2146 static const struct got_error *
2147 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2148     const char *fileindex_path, struct got_object_id *commit_id1,
2149     struct got_object_id *commit_id2, struct got_repository *repo,
2150     got_worktree_checkout_cb progress_cb, void *progress_arg,
2151     got_cancel_cb cancel_cb, void *cancel_arg)
2152 {
2153 	const struct got_error *err = NULL, *sync_err;
2154 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
2155 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
2156 	struct merge_file_cb_arg arg;
2157 
2158 	if (commit_id1) {
2159 		err = got_object_id_by_path(&tree_id1, repo, commit_id1,
2160 		    worktree->path_prefix);
2161 		if (err)
2162 			goto done;
2163 
2164 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
2165 		if (err)
2166 			goto done;
2167 	}
2168 
2169 	err = got_object_id_by_path(&tree_id2, repo, commit_id2,
2170 	    worktree->path_prefix);
2171 	if (err)
2172 		goto done;
2173 
2174 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
2175 	if (err)
2176 		goto done;
2177 
2178 	arg.worktree = worktree;
2179 	arg.fileindex = fileindex;
2180 	arg.progress_cb = progress_cb;
2181 	arg.progress_arg = progress_arg;
2182 	arg.cancel_cb = cancel_cb;
2183 	arg.cancel_arg = cancel_arg;
2184 	arg.commit_id2 = commit_id2;
2185 	err = got_diff_tree(tree1, tree2, "", "", repo, merge_file_cb, &arg, 1);
2186 	sync_err = sync_fileindex(fileindex, fileindex_path);
2187 	if (sync_err && err == NULL)
2188 		err = sync_err;
2189 done:
2190 	if (tree1)
2191 		got_object_tree_close(tree1);
2192 	if (tree2)
2193 		got_object_tree_close(tree2);
2194 	return err;
2195 }
2196 
2197 const struct got_error *
2198 got_worktree_merge_files(struct got_worktree *worktree,
2199     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
2200     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2201     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
2202 {
2203 	const struct got_error *err, *unlockerr;
2204 	char *fileindex_path = NULL;
2205 	struct got_fileindex *fileindex = NULL;
2206 	struct check_merge_ok_arg mok_arg;
2207 
2208 	err = lock_worktree(worktree, LOCK_EX);
2209 	if (err)
2210 		return err;
2211 
2212 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2213 	if (err)
2214 		goto done;
2215 
2216 	mok_arg.worktree = worktree;
2217 	mok_arg.repo = repo;
2218 	err = got_fileindex_for_each_entry_safe(fileindex, check_merge_ok,
2219 	    &mok_arg);
2220 	if (err)
2221 		goto done;
2222 
2223 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
2224 	    commit_id2, repo, progress_cb, progress_arg, cancel_cb, cancel_arg);
2225 done:
2226 	if (fileindex)
2227 		got_fileindex_free(fileindex);
2228 	free(fileindex_path);
2229 	unlockerr = lock_worktree(worktree, LOCK_SH);
2230 	if (unlockerr && err == NULL)
2231 		err = unlockerr;
2232 	return err;
2233 }
2234 
2235 struct diff_dir_cb_arg {
2236     struct got_fileindex *fileindex;
2237     struct got_worktree *worktree;
2238     const char *status_path;
2239     size_t status_path_len;
2240     struct got_repository *repo;
2241     got_worktree_status_cb status_cb;
2242     void *status_arg;
2243     got_cancel_cb cancel_cb;
2244     void *cancel_arg;
2245     /* A pathlist containing per-directory pathlists of ignore patterns. */
2246     struct got_pathlist_head ignores;
2247 };
2248 
2249 static const struct got_error *
2250 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
2251     got_worktree_status_cb status_cb, void *status_arg,
2252     struct got_repository *repo)
2253 {
2254 	const struct got_error *err = NULL;
2255 	unsigned char status = GOT_STATUS_NO_CHANGE;
2256 	unsigned char staged_status = get_staged_status(ie);
2257 	struct stat sb;
2258 	struct got_object_id blob_id, commit_id, staged_blob_id;
2259 	struct got_object_id *blob_idp = NULL, *commit_idp = NULL;
2260 	struct got_object_id *staged_blob_idp = NULL;
2261 
2262 	err = get_file_status(&status, &sb, ie, abspath, repo);
2263 	if (err)
2264 		return err;
2265 
2266 	if (status == GOT_STATUS_NO_CHANGE &&
2267 	    staged_status == GOT_STATUS_NO_CHANGE)
2268 		return NULL;
2269 
2270 	if (got_fileindex_entry_has_blob(ie)) {
2271 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2272 		blob_idp = &blob_id;
2273 	}
2274 	if (got_fileindex_entry_has_commit(ie)) {
2275 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2276 		commit_idp = &commit_id;
2277 	}
2278 	if (staged_status == GOT_STATUS_ADD ||
2279 	    staged_status == GOT_STATUS_MODIFY) {
2280 		memcpy(staged_blob_id.sha1, ie->staged_blob_sha1,
2281 		    SHA1_DIGEST_LENGTH);
2282 		staged_blob_idp = &staged_blob_id;
2283 	}
2284 
2285 	return (*status_cb)(status_arg, status, staged_status,
2286 	    ie->path, blob_idp, staged_blob_idp, commit_idp);
2287 }
2288 
2289 static const struct got_error *
2290 status_old_new(void *arg, struct got_fileindex_entry *ie,
2291     struct dirent *de, const char *parent_path)
2292 {
2293 	const struct got_error *err = NULL;
2294 	struct diff_dir_cb_arg *a = arg;
2295 	char *abspath;
2296 
2297 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2298 		return got_error(GOT_ERR_CANCELLED);
2299 
2300 	if (got_path_cmp(parent_path, a->status_path,
2301 	    strlen(parent_path), a->status_path_len) != 0 &&
2302 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
2303 		return NULL;
2304 
2305 	if (parent_path[0]) {
2306 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
2307 		    parent_path, de->d_name) == -1)
2308 			return got_error_from_errno("asprintf");
2309 	} else {
2310 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
2311 		    de->d_name) == -1)
2312 			return got_error_from_errno("asprintf");
2313 	}
2314 
2315 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
2316 	    a->repo);
2317 	free(abspath);
2318 	return err;
2319 }
2320 
2321 static const struct got_error *
2322 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2323 {
2324 	struct diff_dir_cb_arg *a = arg;
2325 	struct got_object_id blob_id, commit_id;
2326 	unsigned char status;
2327 
2328 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2329 		return got_error(GOT_ERR_CANCELLED);
2330 
2331 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
2332 		return NULL;
2333 
2334 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2335 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2336 	if (got_fileindex_entry_has_file_on_disk(ie))
2337 		status = GOT_STATUS_MISSING;
2338 	else
2339 		status = GOT_STATUS_DELETE;
2340 	return (*a->status_cb)(a->status_arg, status, get_staged_status(ie),
2341 	    ie->path, &blob_id, NULL, &commit_id);
2342 }
2343 
2344 void
2345 free_ignorelist(struct got_pathlist_head *ignorelist)
2346 {
2347 	struct got_pathlist_entry *pe;
2348 
2349 	TAILQ_FOREACH(pe, ignorelist, entry)
2350 		free((char *)pe->path);
2351 	got_pathlist_free(ignorelist);
2352 }
2353 
2354 void
2355 free_ignores(struct got_pathlist_head *ignores)
2356 {
2357 	struct got_pathlist_entry *pe;
2358 
2359 	TAILQ_FOREACH(pe, ignores, entry) {
2360 		struct got_pathlist_head *ignorelist = pe->data;
2361 		free_ignorelist(ignorelist);
2362 		free((char *)pe->path);
2363 	}
2364 	got_pathlist_free(ignores);
2365 }
2366 
2367 static const struct got_error *
2368 read_ignores(struct got_pathlist_head *ignores, const char *path, FILE *f)
2369 {
2370 	const struct got_error *err = NULL;
2371 	struct got_pathlist_entry *pe = NULL;
2372 	struct got_pathlist_head *ignorelist;
2373 	char *line = NULL, *pattern, *dirpath = NULL;
2374 	size_t linesize = 0;
2375 	ssize_t linelen;
2376 
2377 	ignorelist = calloc(1, sizeof(*ignorelist));
2378 	if (ignorelist == NULL)
2379 		return got_error_from_errno("calloc");
2380 	TAILQ_INIT(ignorelist);
2381 
2382 	while ((linelen = getline(&line, &linesize, f)) != -1) {
2383 		if (linelen > 0 && line[linelen - 1] == '\n')
2384 			line[linelen - 1] = '\0';
2385 		if (asprintf(&pattern, "%s%s%s", path, path[0] ? "/" : "",
2386 		    line) == -1) {
2387 			err = got_error_from_errno("asprintf");
2388 			goto done;
2389 		}
2390 		err = got_pathlist_insert(NULL, ignorelist, pattern, NULL);
2391 		if (err)
2392 			goto done;
2393 	}
2394 	if (ferror(f)) {
2395 		err = got_error_from_errno("getline");
2396 		goto done;
2397 	}
2398 
2399 	dirpath = strdup(path);
2400 	if (dirpath == NULL) {
2401 		err = got_error_from_errno("strdup");
2402 		goto done;
2403 	}
2404 	err = got_pathlist_insert(&pe, ignores, dirpath, ignorelist);
2405 done:
2406 	free(line);
2407 	if (err || pe == NULL) {
2408 		free(dirpath);
2409 		free_ignorelist(ignorelist);
2410 	}
2411 	return err;
2412 }
2413 
2414 int
2415 match_ignores(struct got_pathlist_head *ignores, const char *path)
2416 {
2417 	struct got_pathlist_entry *pe;
2418 
2419 	/*
2420 	 * The ignores pathlist contains ignore lists from children before
2421 	 * parents, so we can find the most specific ignorelist by walking
2422 	 * ignores backwards.
2423 	 */
2424 	pe = TAILQ_LAST(ignores, got_pathlist_head);
2425 	while (pe) {
2426 		if (got_path_is_child(path, pe->path, pe->path_len)) {
2427 			struct got_pathlist_head *ignorelist = pe->data;
2428 			struct got_pathlist_entry *pi;
2429 			TAILQ_FOREACH(pi, ignorelist, entry) {
2430 				if (fnmatch(pi->path, path,
2431 				    FNM_PATHNAME | FNM_LEADING_DIR))
2432 					continue;
2433 				return 1;
2434 			}
2435 		}
2436 		pe = TAILQ_PREV(pe, got_pathlist_head, entry);
2437 	}
2438 
2439 	return 0;
2440 }
2441 
2442 static const struct got_error *
2443 add_ignores(struct got_pathlist_head *ignores, const char *root_path,
2444     const char *path)
2445 {
2446 	const struct got_error *err = NULL;
2447 	char *ignorespath;
2448 	FILE *ignoresfile = NULL;
2449 
2450 	/* TODO: read .gitignores as well... */
2451 	if (asprintf(&ignorespath, "%s/%s%s.cvsignore", root_path, path,
2452 	    path[0] ? "/" : "") == -1)
2453 		return got_error_from_errno("asprintf");
2454 
2455 	ignoresfile = fopen(ignorespath, "r");
2456 	if (ignoresfile == NULL) {
2457 		if (errno != ENOENT && errno != EACCES)
2458 			err = got_error_from_errno2("fopen",
2459 			    ignorespath);
2460 	} else
2461 		err = read_ignores(ignores, path, ignoresfile);
2462 
2463 	if (ignoresfile && fclose(ignoresfile) == EOF && err == NULL)
2464 		err = got_error_from_errno2("flose", path);
2465 	free(ignorespath);
2466 	return err;
2467 }
2468 
2469 static const struct got_error *
2470 status_new(void *arg, struct dirent *de, const char *parent_path)
2471 {
2472 	const struct got_error *err = NULL;
2473 	struct diff_dir_cb_arg *a = arg;
2474 	char *path = NULL;
2475 
2476 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2477 		return got_error(GOT_ERR_CANCELLED);
2478 
2479 	/* XXX ignore symlinks for now */
2480 	if (de->d_type == DT_LNK)
2481 		return NULL;
2482 
2483 	if (parent_path[0]) {
2484 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
2485 			return got_error_from_errno("asprintf");
2486 	} else {
2487 		path = de->d_name;
2488 	}
2489 
2490 	if (de->d_type == DT_DIR)
2491 		err = add_ignores(&a->ignores, a->worktree->root_path, path);
2492 	else if (got_path_is_child(path, a->status_path, a->status_path_len)
2493 	    && !match_ignores(&a->ignores, path))
2494 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
2495 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL);
2496 	if (parent_path[0])
2497 		free(path);
2498 	return err;
2499 }
2500 
2501 static const struct got_error *
2502 report_single_file_status(const char *path, const char *ondisk_path,
2503 struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
2504 void *status_arg, struct got_repository *repo)
2505 {
2506 	struct got_fileindex_entry *ie;
2507 	struct stat sb;
2508 
2509 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
2510 	if (ie)
2511 		return report_file_status(ie, ondisk_path, status_cb,
2512 		    status_arg, repo);
2513 
2514 	if (lstat(ondisk_path, &sb) == -1) {
2515 		if (errno != ENOENT)
2516 			return got_error_from_errno2("lstat", ondisk_path);
2517 		return (*status_cb)(status_arg, GOT_STATUS_NONEXISTENT,
2518 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL);
2519 		return NULL;
2520 	}
2521 
2522 	if (S_ISREG(sb.st_mode))
2523 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED,
2524 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL);
2525 
2526 	return NULL;
2527 }
2528 
2529 static const struct got_error *
2530 worktree_status(struct got_worktree *worktree, const char *path,
2531     struct got_fileindex *fileindex, struct got_repository *repo,
2532     got_worktree_status_cb status_cb, void *status_arg,
2533     got_cancel_cb cancel_cb, void *cancel_arg)
2534 {
2535 	const struct got_error *err = NULL;
2536 	DIR *workdir = NULL;
2537 	struct got_fileindex_diff_dir_cb fdiff_cb;
2538 	struct diff_dir_cb_arg arg;
2539 	char *ondisk_path = NULL;
2540 
2541 	if (asprintf(&ondisk_path, "%s%s%s",
2542 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
2543 		return got_error_from_errno("asprintf");
2544 
2545 	workdir = opendir(ondisk_path);
2546 	if (workdir == NULL) {
2547 		if (errno != ENOTDIR && errno != ENOENT && errno != EACCES)
2548 			err = got_error_from_errno2("opendir", ondisk_path);
2549 		else
2550 			err = report_single_file_status(path, ondisk_path,
2551 			    fileindex, status_cb, status_arg, repo);
2552 	} else {
2553 		fdiff_cb.diff_old_new = status_old_new;
2554 		fdiff_cb.diff_old = status_old;
2555 		fdiff_cb.diff_new = status_new;
2556 		arg.fileindex = fileindex;
2557 		arg.worktree = worktree;
2558 		arg.status_path = path;
2559 		arg.status_path_len = strlen(path);
2560 		arg.repo = repo;
2561 		arg.status_cb = status_cb;
2562 		arg.status_arg = status_arg;
2563 		arg.cancel_cb = cancel_cb;
2564 		arg.cancel_arg = cancel_arg;
2565 		TAILQ_INIT(&arg.ignores);
2566 		err = add_ignores(&arg.ignores, worktree->root_path, path);
2567 		if (err == NULL)
2568 			err = got_fileindex_diff_dir(fileindex, workdir,
2569 			    worktree->root_path, path, repo, &fdiff_cb, &arg);
2570 		free_ignores(&arg.ignores);
2571 	}
2572 
2573 	if (workdir)
2574 		closedir(workdir);
2575 	free(ondisk_path);
2576 	return err;
2577 }
2578 
2579 const struct got_error *
2580 got_worktree_status(struct got_worktree *worktree,
2581     struct got_pathlist_head *paths, struct got_repository *repo,
2582     got_worktree_status_cb status_cb, void *status_arg,
2583     got_cancel_cb cancel_cb, void *cancel_arg)
2584 {
2585 	const struct got_error *err = NULL;
2586 	char *fileindex_path = NULL;
2587 	struct got_fileindex *fileindex = NULL;
2588 	struct got_pathlist_entry *pe;
2589 
2590 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2591 	if (err)
2592 		return err;
2593 
2594 	TAILQ_FOREACH(pe, paths, entry) {
2595 		err = worktree_status(worktree, pe->path, fileindex, repo,
2596 			status_cb, status_arg, cancel_cb, cancel_arg);
2597 		if (err)
2598 			break;
2599 	}
2600 	free(fileindex_path);
2601 	got_fileindex_free(fileindex);
2602 	return err;
2603 }
2604 
2605 const struct got_error *
2606 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
2607     const char *arg)
2608 {
2609 	const struct got_error *err = NULL;
2610 	char *resolved, *cwd = NULL, *path = NULL;
2611 	size_t len;
2612 
2613 	*wt_path = NULL;
2614 
2615 	resolved = realpath(arg, NULL);
2616 	if (resolved == NULL) {
2617 		if (errno != ENOENT)
2618 			return got_error_from_errno2("realpath", arg);
2619 		cwd = getcwd(NULL, 0);
2620 		if (cwd == NULL)
2621 			return got_error_from_errno("getcwd");
2622 		if (asprintf(&resolved, "%s/%s", cwd, arg) == -1) {
2623 			err = got_error_from_errno("asprintf");
2624 			goto done;
2625 		}
2626 	}
2627 
2628 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
2629 	    strlen(got_worktree_get_root_path(worktree)))) {
2630 		err = got_error(GOT_ERR_BAD_PATH);
2631 		goto done;
2632 	}
2633 
2634 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
2635 		err = got_path_skip_common_ancestor(&path,
2636 		    got_worktree_get_root_path(worktree), resolved);
2637 		if (err)
2638 			goto done;
2639 	} else {
2640 		path = strdup("");
2641 		if (path == NULL) {
2642 			err = got_error_from_errno("strdup");
2643 			goto done;
2644 		}
2645 	}
2646 
2647 	/* XXX status walk can't deal with trailing slash! */
2648 	len = strlen(path);
2649 	while (len > 0 && path[len - 1] == '/') {
2650 		path[len - 1] = '\0';
2651 		len--;
2652 	}
2653 done:
2654 	free(resolved);
2655 	free(cwd);
2656 	if (err == NULL)
2657 		*wt_path = path;
2658 	else
2659 		free(path);
2660 	return err;
2661 }
2662 
2663 static const struct got_error *
2664 schedule_addition(const char *ondisk_path, struct got_fileindex *fileindex,
2665     const char *relpath, got_worktree_status_cb status_cb, void *status_arg,
2666     struct got_repository *repo)
2667 {
2668 	const struct got_error *err = NULL;
2669 	struct got_fileindex_entry *ie;
2670 	unsigned char status;
2671 	struct stat sb;
2672 
2673 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2674 	if (ie) {
2675 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2676 		if (err)
2677 			return err;
2678 		/* Re-adding an existing entry is a no-op. */
2679 		if (status == GOT_STATUS_ADD)
2680 			return NULL;
2681 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
2682 	}
2683 
2684 	err = got_fileindex_entry_alloc(&ie, ondisk_path, relpath, NULL, NULL);
2685 	if (err)
2686 		return err;
2687 
2688 	err = got_fileindex_entry_add(fileindex, ie);
2689 	if (err) {
2690 		got_fileindex_entry_free(ie);
2691 		return err;
2692 	}
2693 
2694 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2695 }
2696 
2697 const struct got_error *
2698 got_worktree_schedule_add(struct got_worktree *worktree,
2699     struct got_pathlist_head *paths,
2700     got_worktree_status_cb status_cb, void *status_arg,
2701     struct got_repository *repo)
2702 {
2703 	struct got_fileindex *fileindex = NULL;
2704 	char *fileindex_path = NULL;
2705 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2706 	struct got_pathlist_entry *pe;
2707 
2708 	err = lock_worktree(worktree, LOCK_EX);
2709 	if (err)
2710 		return err;
2711 
2712 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2713 	if (err)
2714 		goto done;
2715 
2716 	TAILQ_FOREACH(pe, paths, entry) {
2717 		char *ondisk_path;
2718 		if (asprintf(&ondisk_path, "%s/%s", worktree->root_path,
2719 		    pe->path) == -1)
2720 			return got_error_from_errno("asprintf");
2721 		err = schedule_addition(ondisk_path, fileindex, pe->path,
2722 		    status_cb, status_arg, repo);
2723 		free(ondisk_path);
2724 		if (err)
2725 			break;
2726 	}
2727 	sync_err = sync_fileindex(fileindex, fileindex_path);
2728 	if (sync_err && err == NULL)
2729 		err = sync_err;
2730 done:
2731 	free(fileindex_path);
2732 	if (fileindex)
2733 		got_fileindex_free(fileindex);
2734 	unlockerr = lock_worktree(worktree, LOCK_SH);
2735 	if (unlockerr && err == NULL)
2736 		err = unlockerr;
2737 	return err;
2738 }
2739 
2740 static const struct got_error *
2741 schedule_for_deletion(const char *ondisk_path, struct got_fileindex *fileindex,
2742     const char *relpath, int delete_local_mods,
2743     got_worktree_status_cb status_cb, void *status_arg,
2744     struct got_repository *repo)
2745 {
2746 	const struct got_error *err = NULL;
2747 	struct got_fileindex_entry *ie = NULL;
2748 	unsigned char status, staged_status;
2749 	struct stat sb;
2750 
2751 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2752 	if (ie == NULL)
2753 		return got_error(GOT_ERR_BAD_PATH);
2754 
2755 	staged_status = get_staged_status(ie);
2756 	if (staged_status != GOT_STATUS_NO_CHANGE) {
2757 		if (staged_status == GOT_STATUS_DELETE)
2758 			return NULL;
2759 		return got_error_path(relpath, GOT_ERR_FILE_STAGED);
2760 	}
2761 
2762 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2763 	if (err)
2764 		return err;
2765 
2766 	if (status != GOT_STATUS_NO_CHANGE) {
2767 		if (status == GOT_STATUS_DELETE)
2768 			return NULL;
2769 		if (status == GOT_STATUS_MODIFY && !delete_local_mods)
2770 			return got_error_path(relpath, GOT_ERR_FILE_MODIFIED);
2771 		if (status != GOT_STATUS_MODIFY &&
2772 		    status != GOT_STATUS_MISSING)
2773 			return got_error_path(relpath, GOT_ERR_FILE_STATUS);
2774 	}
2775 
2776 	if (status != GOT_STATUS_MISSING && unlink(ondisk_path) != 0)
2777 		return got_error_from_errno2("unlink", ondisk_path);
2778 
2779 	got_fileindex_entry_mark_deleted_from_disk(ie);
2780 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2781 }
2782 
2783 const struct got_error *
2784 got_worktree_schedule_delete(struct got_worktree *worktree,
2785     struct got_pathlist_head *paths, int delete_local_mods,
2786     got_worktree_status_cb status_cb, void *status_arg,
2787     struct got_repository *repo)
2788 {
2789 	struct got_fileindex *fileindex = NULL;
2790 	char *fileindex_path = NULL;
2791 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2792 	struct got_pathlist_entry *pe;
2793 
2794 	err = lock_worktree(worktree, LOCK_EX);
2795 	if (err)
2796 		return err;
2797 
2798 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2799 	if (err)
2800 		goto done;
2801 
2802 	TAILQ_FOREACH(pe, paths, entry) {
2803 		char *ondisk_path;
2804 		if (asprintf(&ondisk_path, "%s/%s", worktree->root_path,
2805 		    pe->path) == -1)
2806 			return got_error_from_errno("asprintf");
2807 		err = schedule_for_deletion(ondisk_path, fileindex, pe->path,
2808 		    delete_local_mods, status_cb, status_arg, repo);
2809 		free(ondisk_path);
2810 		if (err)
2811 			break;
2812 	}
2813 	sync_err = sync_fileindex(fileindex, fileindex_path);
2814 	if (sync_err && err == NULL)
2815 		err = sync_err;
2816 done:
2817 	free(fileindex_path);
2818 	if (fileindex)
2819 		got_fileindex_free(fileindex);
2820 	unlockerr = lock_worktree(worktree, LOCK_SH);
2821 	if (unlockerr && err == NULL)
2822 		err = unlockerr;
2823 	return err;
2824 }
2825 
2826 static const struct got_error *
2827 copy_one_line(FILE *infile, FILE *outfile, FILE *rejectfile)
2828 {
2829 	const struct got_error *err = NULL;
2830 	char *line = NULL;
2831 	size_t linesize = 0, n;
2832 	ssize_t linelen;
2833 
2834 	linelen = getline(&line, &linesize, infile);
2835 	if (linelen == -1) {
2836 		if (ferror(infile)) {
2837 			err = got_error_from_errno("getline");
2838 			goto done;
2839 		}
2840 		return NULL;
2841 	}
2842 	if (outfile) {
2843 		n = fwrite(line, 1, linelen, outfile);
2844 		if (n != linelen) {
2845 			err = got_ferror(outfile, GOT_ERR_IO);
2846 			goto done;
2847 		}
2848 	}
2849 	if (rejectfile) {
2850 		n = fwrite(line, 1, linelen, rejectfile);
2851 		if (n != linelen)
2852 			err = got_ferror(outfile, GOT_ERR_IO);
2853 	}
2854 done:
2855 	free(line);
2856 	return err;
2857 }
2858 
2859 static const struct got_error *
2860 skip_one_line(FILE *f)
2861 {
2862 	char *line = NULL;
2863 	size_t linesize = 0;
2864 	ssize_t linelen;
2865 
2866 	linelen = getline(&line, &linesize, f);
2867 	if (linelen == -1) {
2868 		if (ferror(f))
2869 			return got_error_from_errno("getline");
2870 		return NULL;
2871 	}
2872 	free(line);
2873 	return NULL;
2874 }
2875 
2876 static const struct got_error *
2877 copy_change(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
2878     int start_old, int end_old, int start_new, int end_new,
2879     FILE *outfile, FILE *rejectfile)
2880  {
2881 	const struct got_error *err;
2882 
2883 	/* Copy old file's lines leading up to patch. */
2884 	while (!feof(f1) && *line_cur1 < start_old) {
2885 		err = copy_one_line(f1, outfile, NULL);
2886 		if (err)
2887 			return err;
2888 		(*line_cur1)++;
2889 	}
2890 	/* Skip new file's lines leading up to patch. */
2891 	while (!feof(f2) && *line_cur2 < start_new) {
2892 		if (rejectfile)
2893 			err = copy_one_line(f2, NULL, rejectfile);
2894 		else
2895 			err = skip_one_line(f2);
2896 		if (err)
2897 			return err;
2898 		(*line_cur2)++;
2899 	}
2900 	/* Copy patched lines. */
2901 	while (!feof(f2) && *line_cur2 <= end_new) {
2902 		err = copy_one_line(f2, outfile, NULL);
2903 		if (err)
2904 			return err;
2905 		(*line_cur2)++;
2906 	}
2907 	/* Skip over old file's replaced lines. */
2908 	while (!feof(f1) && *line_cur1 <= end_old) {
2909 		if (rejectfile)
2910 			err = copy_one_line(f1, NULL, rejectfile);
2911 		else
2912 			err = skip_one_line(f1);
2913 		if (err)
2914 			return err;
2915 		(*line_cur1)++;
2916 	}
2917 
2918 	return NULL;
2919 }
2920 
2921 static const struct got_error *
2922 copy_remaining_content(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
2923     FILE *outfile, FILE *rejectfile)
2924 {
2925 	const struct got_error *err;
2926 
2927 	if (outfile) {
2928 		/* Copy old file's lines until EOF. */
2929 		while (!feof(f1)) {
2930 			err = copy_one_line(f1, outfile, NULL);
2931 			if (err)
2932 				return err;
2933 			(*line_cur1)++;
2934 		}
2935 	}
2936 	if (rejectfile) {
2937 		/* Copy new file's lines until EOF. */
2938 		while (!feof(f2)) {
2939 			err = copy_one_line(f2, NULL, rejectfile);
2940 			if (err)
2941 				return err;
2942 			(*line_cur2)++;
2943 		}
2944 	}
2945 
2946 	return NULL;
2947 }
2948 
2949 static const struct got_error *
2950 apply_or_reject_change(int *choice, struct got_diff_change *change, int n,
2951     int nchanges, struct got_diff_state *ds, struct got_diff_args *args,
2952     int diff_flags, const char *relpath, FILE *f1, FILE *f2, int *line_cur1,
2953     int *line_cur2, FILE *outfile, FILE *rejectfile,
2954     got_worktree_patch_cb patch_cb, void *patch_arg)
2955 {
2956 	const struct got_error *err = NULL;
2957 	int start_old = change->cv.a;
2958 	int end_old = change->cv.b;
2959 	int start_new = change->cv.c;
2960 	int end_new = change->cv.d;
2961 	long pos1, pos2;
2962 	FILE *hunkfile;
2963 
2964 	*choice = GOT_PATCH_CHOICE_NONE;
2965 
2966 	hunkfile = got_opentemp();
2967 	if (hunkfile == NULL)
2968 		return got_error_from_errno("got_opentemp");
2969 
2970 	pos1 = ftell(f1);
2971 	pos2 = ftell(f2);
2972 
2973 	/* XXX TODO needs error checking */
2974 	got_diff_dump_change(hunkfile, change, ds, args, f1, f2, diff_flags);
2975 
2976 	if (fseek(f1, pos1, SEEK_SET) == -1) {
2977 		err = got_ferror(f1, GOT_ERR_IO);
2978 		goto done;
2979 	}
2980 	if (fseek(f2, pos2, SEEK_SET) == -1) {
2981 		err = got_ferror(f1, GOT_ERR_IO);
2982 		goto done;
2983 	}
2984 	if (fseek(hunkfile, 0L, SEEK_SET) == -1) {
2985 		err = got_ferror(hunkfile, GOT_ERR_IO);
2986 		goto done;
2987 	}
2988 
2989 	err = (*patch_cb)(choice, patch_arg, GOT_STATUS_MODIFY, relpath,
2990 	    hunkfile, n, nchanges);
2991 	if (err)
2992 		goto done;
2993 
2994 	switch (*choice) {
2995 	case GOT_PATCH_CHOICE_YES:
2996 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
2997 		    end_old, start_new, end_new, outfile, rejectfile);
2998 		break;
2999 	case GOT_PATCH_CHOICE_NO:
3000 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
3001 		    end_old, start_new, end_new, rejectfile, outfile);
3002 		break;
3003 	case GOT_PATCH_CHOICE_QUIT:
3004 		break;
3005 	default:
3006 		err = got_error(GOT_ERR_PATCH_CHOICE);
3007 		break;
3008 	}
3009 done:
3010 	if (hunkfile && fclose(hunkfile) == EOF && err == NULL)
3011 		err = got_error_from_errno("fclose");
3012 	return err;
3013 }
3014 
3015 struct revert_file_args {
3016 	struct got_worktree *worktree;
3017 	struct got_fileindex *fileindex;
3018 	got_worktree_checkout_cb progress_cb;
3019 	void *progress_arg;
3020 	got_worktree_patch_cb patch_cb;
3021 	void *patch_arg;
3022 	struct got_repository *repo;
3023 };
3024 
3025 static const struct got_error *
3026 create_patched_content(char **path_outfile, int reverse_patch,
3027     struct got_object_id *blob_id, const char *path2,
3028     const char *relpath, struct got_repository *repo,
3029     got_worktree_patch_cb patch_cb, void *patch_arg)
3030 {
3031 	const struct got_error *err;
3032 	struct got_blob_object *blob = NULL;
3033 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL;
3034 	char *path1 = NULL, *id_str = NULL;
3035 	struct stat sb1, sb2;
3036 	struct got_diff_changes *changes = NULL;
3037 	struct got_diff_state *ds = NULL;
3038 	struct got_diff_args *args = NULL;
3039 	struct got_diff_change *change;
3040 	int diff_flags = 0, line_cur1 = 1, line_cur2 = 1, have_content = 0;
3041 	int n = 0;
3042 
3043 	*path_outfile = NULL;
3044 
3045 	err = got_object_id_str(&id_str, blob_id);
3046 	if (err)
3047 		return err;
3048 
3049 	f2 = fopen(path2, "r");
3050 	if (f2 == NULL) {
3051 		err = got_error_from_errno2("fopen", path2);
3052 		goto done;
3053 	}
3054 
3055 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192);
3056 	if (err)
3057 		goto done;
3058 
3059 	err = got_opentemp_named(&path1, &f1, "got-patched-blob");
3060 	if (err)
3061 		goto done;
3062 
3063 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
3064 	if (err)
3065 		goto done;
3066 
3067 	if (stat(path1, &sb1) == -1) {
3068 		err = got_error_from_errno2("stat", path1);
3069 		goto done;
3070 	}
3071 	if (stat(path2, &sb2) == -1) {
3072 		err = got_error_from_errno2("stat", path2);
3073 		goto done;
3074 	}
3075 
3076 	err = got_diff_files(&changes, &ds, &args, &diff_flags,
3077 	    f1, sb1.st_size, id_str, f2, sb2.st_size, path2, 3, NULL);
3078 	if (err)
3079 		goto done;
3080 
3081 	err = got_opentemp_named(path_outfile, &outfile, "got-patched-content");
3082 	if (err)
3083 		goto done;
3084 
3085 	if (fseek(f1, 0L, SEEK_SET) == -1)
3086 		return got_ferror(f1, GOT_ERR_IO);
3087 	if (fseek(f2, 0L, SEEK_SET) == -1)
3088 		return got_ferror(f2, GOT_ERR_IO);
3089 	SIMPLEQ_FOREACH(change, &changes->entries, entry) {
3090 		int choice;
3091 		err = apply_or_reject_change(&choice, change, ++n,
3092 		    changes->nchanges, ds, args, diff_flags, relpath,
3093 		    f1, f2, &line_cur1, &line_cur2,
3094 		    reverse_patch ? NULL : outfile,
3095 		    reverse_patch ? outfile : NULL,
3096 		    patch_cb, patch_arg);
3097 		if (err)
3098 			goto done;
3099 		if (choice == GOT_PATCH_CHOICE_YES)
3100 			have_content = 1;
3101 		else if (choice == GOT_PATCH_CHOICE_QUIT)
3102 			break;
3103 	}
3104 	if (have_content)
3105 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
3106 		    reverse_patch ? NULL : outfile,
3107 		    reverse_patch ? outfile : NULL);
3108 done:
3109 	free(id_str);
3110 	if (blob)
3111 		got_object_blob_close(blob);
3112 	if (f1 && fclose(f1) == EOF && err == NULL)
3113 		err = got_error_from_errno2("fclose", path1);
3114 	if (f2 && fclose(f2) == EOF && err == NULL)
3115 		err = got_error_from_errno2("fclose", path2);
3116 	if (outfile && fclose(outfile) == EOF && err == NULL)
3117 		err = got_error_from_errno2("fclose", *path_outfile);
3118 	if (path1 && unlink(path1) == -1 && err == NULL)
3119 		err = got_error_from_errno2("unlink", path1);
3120 	if (err || !have_content) {
3121 		if (*path_outfile && unlink(*path_outfile) == -1 && err == NULL)
3122 			err = got_error_from_errno2("unlink", *path_outfile);
3123 		free(*path_outfile);
3124 		*path_outfile = NULL;
3125 	}
3126 	free(args);
3127 	if (ds) {
3128 		got_diff_state_free(ds);
3129 		free(ds);
3130 	}
3131 	if (changes)
3132 		got_diff_free_changes(changes);
3133 	free(path1);
3134 	return err;
3135 }
3136 
3137 static const struct got_error *
3138 revert_file(void *arg, unsigned char status, unsigned char staged_status,
3139     const char *relpath, struct got_object_id *blob_id,
3140     struct got_object_id *staged_blob_id, struct got_object_id *commit_id)
3141 {
3142 	struct revert_file_args *a = arg;
3143 	const struct got_error *err = NULL;
3144 	char *parent_path = NULL;
3145 	struct got_fileindex_entry *ie;
3146 	struct got_tree_object *tree = NULL;
3147 	struct got_object_id *tree_id = NULL;
3148 	const struct got_tree_entry *te = NULL;
3149 	char *tree_path = NULL, *te_name;
3150 	char *ondisk_path = NULL, *path_content = NULL;
3151 	struct got_blob_object *blob = NULL;
3152 
3153 	/* Reverting a staged deletion is a no-op. */
3154 	if (status == GOT_STATUS_DELETE &&
3155 	    staged_status != GOT_STATUS_NO_CHANGE)
3156 		return NULL;
3157 
3158 	if (status == GOT_STATUS_UNVERSIONED)
3159 		return (*a->progress_cb)(a->progress_arg,
3160 		    GOT_STATUS_UNVERSIONED, relpath);
3161 
3162 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
3163 	if (ie == NULL)
3164 		return got_error(GOT_ERR_BAD_PATH);
3165 
3166 	/* Construct in-repository path of tree which contains this blob. */
3167 	err = got_path_dirname(&parent_path, ie->path);
3168 	if (err) {
3169 		if (err->code != GOT_ERR_BAD_PATH)
3170 			goto done;
3171 		parent_path = strdup("/");
3172 		if (parent_path == NULL) {
3173 			err = got_error_from_errno("strdup");
3174 			goto done;
3175 		}
3176 	}
3177 	if (got_path_is_root_dir(a->worktree->path_prefix)) {
3178 		tree_path = strdup(parent_path);
3179 		if (tree_path == NULL) {
3180 			err = got_error_from_errno("strdup");
3181 			goto done;
3182 		}
3183 	} else {
3184 		if (got_path_is_root_dir(parent_path)) {
3185 			tree_path = strdup(a->worktree->path_prefix);
3186 			if (tree_path == NULL) {
3187 				err = got_error_from_errno("strdup");
3188 				goto done;
3189 			}
3190 		} else {
3191 			if (asprintf(&tree_path, "%s/%s",
3192 			    a->worktree->path_prefix, parent_path) == -1) {
3193 				err = got_error_from_errno("asprintf");
3194 				goto done;
3195 			}
3196 		}
3197 	}
3198 
3199 	err = got_object_id_by_path(&tree_id, a->repo,
3200 	    a->worktree->base_commit_id, tree_path);
3201 	if (err) {
3202 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
3203 		    (status == GOT_STATUS_ADD ||
3204 		    staged_status == GOT_STATUS_ADD)))
3205 			goto done;
3206 	} else {
3207 		err = got_object_open_as_tree(&tree, a->repo, tree_id);
3208 		if (err)
3209 			goto done;
3210 
3211 		te_name = basename(ie->path);
3212 		if (te_name == NULL) {
3213 			err = got_error_from_errno2("basename", ie->path);
3214 			goto done;
3215 		}
3216 
3217 		te = got_object_tree_find_entry(tree, te_name);
3218 		if (te == NULL && status != GOT_STATUS_ADD &&
3219 		    staged_status != GOT_STATUS_ADD) {
3220 			err = got_error(GOT_ERR_NO_TREE_ENTRY);
3221 			goto done;
3222 		}
3223 	}
3224 
3225 	switch (status) {
3226 	case GOT_STATUS_ADD:
3227 		if (a->patch_cb) {
3228 			int choice = GOT_PATCH_CHOICE_NONE;
3229 			err = (*a->patch_cb)(&choice, a->patch_arg,
3230 			    status, ie->path, NULL, 1, 1);
3231 			if (err)
3232 				goto done;
3233 			if (choice != GOT_PATCH_CHOICE_YES)
3234 				break;
3235 		}
3236 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_REVERT,
3237 		    ie->path);
3238 		if (err)
3239 			goto done;
3240 		got_fileindex_entry_remove(a->fileindex, ie);
3241 		break;
3242 	case GOT_STATUS_DELETE:
3243 		if (a->patch_cb) {
3244 			int choice = GOT_PATCH_CHOICE_NONE;
3245 			err = (*a->patch_cb)(&choice, a->patch_arg,
3246 			    status, ie->path, NULL, 1, 1);
3247 			if (err)
3248 				goto done;
3249 			if (choice != GOT_PATCH_CHOICE_YES)
3250 				break;
3251 		}
3252 		/* fall through */
3253 	case GOT_STATUS_MODIFY:
3254 	case GOT_STATUS_CONFLICT:
3255 	case GOT_STATUS_MISSING: {
3256 		struct got_object_id id;
3257 		if (staged_status == GOT_STATUS_ADD ||
3258 		    staged_status == GOT_STATUS_MODIFY) {
3259 			memcpy(id.sha1, ie->staged_blob_sha1,
3260 			    SHA1_DIGEST_LENGTH);
3261 		} else
3262 			memcpy(id.sha1, ie->blob_sha1,
3263 			    SHA1_DIGEST_LENGTH);
3264 		err = got_object_open_as_blob(&blob, a->repo, &id, 8192);
3265 		if (err)
3266 			goto done;
3267 
3268 		if (asprintf(&ondisk_path, "%s/%s",
3269 		    got_worktree_get_root_path(a->worktree), relpath) == -1) {
3270 			err = got_error_from_errno("asprintf");
3271 			goto done;
3272 		}
3273 
3274 		if (a->patch_cb && (status == GOT_STATUS_MODIFY ||
3275 		    status == GOT_STATUS_CONFLICT)) {
3276 			err = create_patched_content(&path_content, 1, &id,
3277 			    ondisk_path, ie->path, a->repo,
3278 			    a->patch_cb, a->patch_arg);
3279 			if (err || path_content == NULL)
3280 				break;
3281 			if (rename(path_content, ondisk_path) == -1) {
3282 				err = got_error_from_errno3("rename",
3283 				    path_content, ondisk_path);
3284 				goto done;
3285 			}
3286 		} else {
3287 			err = install_blob(a->worktree, ondisk_path, ie->path,
3288 			    te ? te->mode : GOT_DEFAULT_FILE_MODE,
3289 			    got_fileindex_perms_to_st(ie), blob, 0, 1,
3290 			    a->repo, a->progress_cb, a->progress_arg);
3291 			if (err)
3292 				goto done;
3293 			if (status == GOT_STATUS_DELETE) {
3294 				err = update_blob_fileindex_entry(a->worktree,
3295 				    a->fileindex, ie, ondisk_path, ie->path,
3296 				    blob, 1);
3297 				if (err)
3298 					goto done;
3299 			}
3300 		}
3301 		break;
3302 	}
3303 	default:
3304 		break;
3305 	}
3306 done:
3307 	free(ondisk_path);
3308 	free(path_content);
3309 	free(parent_path);
3310 	free(tree_path);
3311 	if (blob)
3312 		got_object_blob_close(blob);
3313 	if (tree)
3314 		got_object_tree_close(tree);
3315 	free(tree_id);
3316 	return err;
3317 }
3318 
3319 const struct got_error *
3320 got_worktree_revert(struct got_worktree *worktree,
3321     struct got_pathlist_head *paths,
3322     got_worktree_checkout_cb progress_cb, void *progress_arg,
3323     got_worktree_patch_cb patch_cb, void *patch_arg,
3324     struct got_repository *repo)
3325 {
3326 	struct got_fileindex *fileindex = NULL;
3327 	char *fileindex_path = NULL;
3328 	const struct got_error *err = NULL, *unlockerr = NULL;
3329 	const struct got_error *sync_err = NULL;
3330 	struct got_pathlist_entry *pe;
3331 	struct revert_file_args rfa;
3332 
3333 	err = lock_worktree(worktree, LOCK_EX);
3334 	if (err)
3335 		return err;
3336 
3337 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3338 	if (err)
3339 		goto done;
3340 
3341 	rfa.worktree = worktree;
3342 	rfa.fileindex = fileindex;
3343 	rfa.progress_cb = progress_cb;
3344 	rfa.progress_arg = progress_arg;
3345 	rfa.patch_cb = patch_cb;
3346 	rfa.patch_arg = patch_arg;
3347 	rfa.repo = repo;
3348 	TAILQ_FOREACH(pe, paths, entry) {
3349 		err = worktree_status(worktree, pe->path, fileindex, repo,
3350 		    revert_file, &rfa, NULL, NULL);
3351 		if (err)
3352 			break;
3353 	}
3354 	sync_err = sync_fileindex(fileindex, fileindex_path);
3355 	if (sync_err && err == NULL)
3356 		err = sync_err;
3357 done:
3358 	free(fileindex_path);
3359 	if (fileindex)
3360 		got_fileindex_free(fileindex);
3361 	unlockerr = lock_worktree(worktree, LOCK_SH);
3362 	if (unlockerr && err == NULL)
3363 		err = unlockerr;
3364 	return err;
3365 }
3366 
3367 static void
3368 free_commitable(struct got_commitable *ct)
3369 {
3370 	free(ct->path);
3371 	free(ct->in_repo_path);
3372 	free(ct->ondisk_path);
3373 	free(ct->blob_id);
3374 	free(ct->base_blob_id);
3375 	free(ct->staged_blob_id);
3376 	free(ct->base_commit_id);
3377 	free(ct);
3378 }
3379 
3380 struct collect_commitables_arg {
3381 	struct got_pathlist_head *commitable_paths;
3382 	struct got_repository *repo;
3383 	struct got_worktree *worktree;
3384 	int have_staged_files;
3385 };
3386 
3387 static const struct got_error *
3388 collect_commitables(void *arg, unsigned char status,
3389     unsigned char staged_status, const char *relpath,
3390     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
3391     struct got_object_id *commit_id)
3392 {
3393 	struct collect_commitables_arg *a = arg;
3394 	const struct got_error *err = NULL;
3395 	struct got_commitable *ct = NULL;
3396 	struct got_pathlist_entry *new = NULL;
3397 	char *parent_path = NULL, *path = NULL;
3398 	struct stat sb;
3399 
3400 	if (a->have_staged_files) {
3401 		if (staged_status != GOT_STATUS_MODIFY &&
3402 		    staged_status != GOT_STATUS_ADD &&
3403 		    staged_status != GOT_STATUS_DELETE)
3404 			return NULL;
3405 	} else {
3406 		if (status == GOT_STATUS_CONFLICT)
3407 			return got_error(GOT_ERR_COMMIT_CONFLICT);
3408 
3409 		if (status != GOT_STATUS_MODIFY &&
3410 		    status != GOT_STATUS_ADD &&
3411 		    status != GOT_STATUS_DELETE)
3412 			return NULL;
3413 	}
3414 
3415 	if (asprintf(&path, "/%s", relpath) == -1) {
3416 		err = got_error_from_errno("asprintf");
3417 		goto done;
3418 	}
3419 	if (strcmp(path, "/") == 0) {
3420 		parent_path = strdup("");
3421 		if (parent_path == NULL)
3422 			return got_error_from_errno("strdup");
3423 	} else {
3424 		err = got_path_dirname(&parent_path, path);
3425 		if (err)
3426 			return err;
3427 	}
3428 
3429 	ct = calloc(1, sizeof(*ct));
3430 	if (ct == NULL) {
3431 		err = got_error_from_errno("calloc");
3432 		goto done;
3433 	}
3434 
3435 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
3436 	    relpath) == -1) {
3437 		err = got_error_from_errno("asprintf");
3438 		goto done;
3439 	}
3440 	if (status == GOT_STATUS_DELETE || staged_status == GOT_STATUS_DELETE) {
3441 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
3442 	} else {
3443 		if (lstat(ct->ondisk_path, &sb) != 0) {
3444 			err = got_error_from_errno2("lstat", ct->ondisk_path);
3445 			goto done;
3446 		}
3447 		ct->mode = sb.st_mode;
3448 	}
3449 
3450 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
3451 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
3452 	    relpath) == -1) {
3453 		err = got_error_from_errno("asprintf");
3454 		goto done;
3455 	}
3456 
3457 	ct->status = status;
3458 	ct->staged_status = staged_status;
3459 	ct->blob_id = NULL; /* will be filled in when blob gets created */
3460 	if (ct->status != GOT_STATUS_ADD &&
3461 	    ct->staged_status != GOT_STATUS_ADD) {
3462 		ct->base_blob_id = got_object_id_dup(blob_id);
3463 		if (ct->base_blob_id == NULL) {
3464 			err = got_error_from_errno("got_object_id_dup");
3465 			goto done;
3466 		}
3467 		ct->base_commit_id = got_object_id_dup(commit_id);
3468 		if (ct->base_commit_id == NULL) {
3469 			err = got_error_from_errno("got_object_id_dup");
3470 			goto done;
3471 		}
3472 	}
3473 	if (ct->staged_status == GOT_STATUS_ADD ||
3474 	    ct->staged_status == GOT_STATUS_MODIFY) {
3475 		ct->staged_blob_id = got_object_id_dup(staged_blob_id);
3476 		if (ct->staged_blob_id == NULL) {
3477 			err = got_error_from_errno("got_object_id_dup");
3478 			goto done;
3479 		}
3480 	}
3481 	ct->path = strdup(path);
3482 	if (ct->path == NULL) {
3483 		err = got_error_from_errno("strdup");
3484 		goto done;
3485 	}
3486 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
3487 done:
3488 	if (ct && (err || new == NULL))
3489 		free_commitable(ct);
3490 	free(parent_path);
3491 	free(path);
3492 	return err;
3493 }
3494 
3495 static const struct got_error *write_tree(struct got_object_id **,
3496     struct got_tree_object *, const char *, struct got_pathlist_head *,
3497     got_worktree_status_cb status_cb, void *status_arg,
3498     struct got_repository *);
3499 
3500 static const struct got_error *
3501 write_subtree(struct got_object_id **new_subtree_id,
3502     struct got_tree_entry *te, const char *parent_path,
3503     struct got_pathlist_head *commitable_paths,
3504     got_worktree_status_cb status_cb, void *status_arg,
3505     struct got_repository *repo)
3506 {
3507 	const struct got_error *err = NULL;
3508 	struct got_tree_object *subtree;
3509 	char *subpath;
3510 
3511 	if (asprintf(&subpath, "%s%s%s", parent_path,
3512 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
3513 		return got_error_from_errno("asprintf");
3514 
3515 	err = got_object_open_as_tree(&subtree, repo, te->id);
3516 	if (err)
3517 		return err;
3518 
3519 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
3520 	    status_cb, status_arg, repo);
3521 	got_object_tree_close(subtree);
3522 	free(subpath);
3523 	return err;
3524 }
3525 
3526 static const struct got_error *
3527 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
3528 {
3529 	const struct got_error *err = NULL;
3530 	char *ct_parent_path = NULL;
3531 
3532 	*match = 0;
3533 
3534 	if (strchr(ct->in_repo_path, '/') == NULL) {
3535 		*match = got_path_is_root_dir(path);
3536 		return NULL;
3537 	}
3538 
3539 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
3540 	if (err)
3541 		return err;
3542 	*match = (strcmp(path, ct_parent_path) == 0);
3543 	free(ct_parent_path);
3544 	return err;
3545 }
3546 
3547 static mode_t
3548 get_ct_file_mode(struct got_commitable *ct)
3549 {
3550 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
3551 }
3552 
3553 static const struct got_error *
3554 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
3555     struct got_tree_entry *te, struct got_commitable *ct)
3556 {
3557 	const struct got_error *err = NULL;
3558 
3559 	*new_te = NULL;
3560 
3561 	err = got_object_tree_entry_dup(new_te, te);
3562 	if (err)
3563 		goto done;
3564 
3565 	(*new_te)->mode = get_ct_file_mode(ct);
3566 
3567 	free((*new_te)->id);
3568 	if (ct->staged_status == GOT_STATUS_MODIFY)
3569 		(*new_te)->id = got_object_id_dup(ct->staged_blob_id);
3570 	else
3571 		(*new_te)->id = got_object_id_dup(ct->blob_id);
3572 	if ((*new_te)->id == NULL) {
3573 		err = got_error_from_errno("got_object_id_dup");
3574 		goto done;
3575 	}
3576 done:
3577 	if (err && *new_te) {
3578 		got_object_tree_entry_close(*new_te);
3579 		*new_te = NULL;
3580 	}
3581 	return err;
3582 }
3583 
3584 static const struct got_error *
3585 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
3586     struct got_commitable *ct)
3587 {
3588 	const struct got_error *err = NULL;
3589 	char *ct_name;
3590 
3591 	 *new_te = NULL;
3592 
3593 	*new_te = calloc(1, sizeof(**new_te));
3594 	if (*new_te == NULL)
3595 		return got_error_from_errno("calloc");
3596 
3597 	ct_name = basename(ct->path);
3598 	if (ct_name == NULL) {
3599 		err = got_error_from_errno2("basename", ct->path);
3600 		goto done;
3601 	}
3602 	(*new_te)->name = strdup(ct_name);
3603 	if ((*new_te)->name == NULL) {
3604 		err = got_error_from_errno("strdup");
3605 		goto done;
3606 	}
3607 
3608 	(*new_te)->mode = get_ct_file_mode(ct);
3609 
3610 	if (ct->staged_status == GOT_STATUS_ADD)
3611 		(*new_te)->id = got_object_id_dup(ct->staged_blob_id);
3612 	else
3613 		(*new_te)->id = got_object_id_dup(ct->blob_id);
3614 	if ((*new_te)->id == NULL) {
3615 		err = got_error_from_errno("got_object_id_dup");
3616 		goto done;
3617 	}
3618 done:
3619 	if (err && *new_te) {
3620 		got_object_tree_entry_close(*new_te);
3621 		*new_te = NULL;
3622 	}
3623 	return err;
3624 }
3625 
3626 static const struct got_error *
3627 insert_tree_entry(struct got_tree_entry *new_te,
3628     struct got_pathlist_head *paths)
3629 {
3630 	const struct got_error *err = NULL;
3631 	struct got_pathlist_entry *new_pe;
3632 
3633 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
3634 	if (err)
3635 		return err;
3636 	if (new_pe == NULL)
3637 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
3638 	return NULL;
3639 }
3640 
3641 static const struct got_error *
3642 report_ct_status(struct got_commitable *ct,
3643     got_worktree_status_cb status_cb, void *status_arg)
3644 {
3645 	const char *ct_path = ct->path;
3646 	unsigned char status;
3647 
3648 	while (ct_path[0] == '/')
3649 		ct_path++;
3650 
3651 	if (ct->staged_status != GOT_STATUS_NO_CHANGE)
3652 		status = ct->staged_status;
3653 	else
3654 		status = ct->status;
3655 
3656 	return (*status_cb)(status_arg, status, GOT_STATUS_NO_CHANGE,
3657 	    ct_path, ct->blob_id, NULL, NULL);
3658 }
3659 
3660 static const struct got_error *
3661 match_modified_subtree(int *modified, struct got_tree_entry *te,
3662     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
3663 {
3664 	const struct got_error *err = NULL;
3665 	struct got_pathlist_entry *pe;
3666 	char *te_path;
3667 
3668 	*modified = 0;
3669 
3670 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
3671 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
3672 	    te->name) == -1)
3673 		return got_error_from_errno("asprintf");
3674 
3675 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3676 		struct got_commitable *ct = pe->data;
3677 		*modified = got_path_is_child(ct->in_repo_path, te_path,
3678 		    strlen(te_path));
3679 		 if (*modified)
3680 			break;
3681 	}
3682 
3683 	free(te_path);
3684 	return err;
3685 }
3686 
3687 static const struct got_error *
3688 match_deleted_or_modified_ct(struct got_commitable **ctp,
3689     struct got_tree_entry *te, const char *base_tree_path,
3690     struct got_pathlist_head *commitable_paths)
3691 {
3692 	const struct got_error *err = NULL;
3693 	struct got_pathlist_entry *pe;
3694 
3695 	*ctp = NULL;
3696 
3697 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3698 		struct got_commitable *ct = pe->data;
3699 		char *ct_name = NULL;
3700 		int path_matches;
3701 
3702 		if (ct->staged_status == GOT_STATUS_NO_CHANGE) {
3703 			if (ct->status != GOT_STATUS_MODIFY &&
3704 			    ct->status != GOT_STATUS_DELETE)
3705 				continue;
3706 		} else {
3707 			if (ct->staged_status != GOT_STATUS_MODIFY &&
3708 			    ct->staged_status != GOT_STATUS_DELETE)
3709 				continue;
3710 		}
3711 
3712 		if (got_object_id_cmp(ct->base_blob_id, te->id) != 0)
3713 			continue;
3714 
3715 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
3716 		 if (err)
3717 			return err;
3718 		if (!path_matches)
3719 			continue;
3720 
3721 		ct_name = basename(pe->path);
3722 		if (ct_name == NULL)
3723 			return got_error_from_errno2("basename", pe->path);
3724 
3725 		if (strcmp(te->name, ct_name) != 0)
3726 			continue;
3727 
3728 		*ctp = ct;
3729 		break;
3730 	}
3731 
3732 	return err;
3733 }
3734 
3735 static const struct got_error *
3736 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
3737     const char *child_path, const char *path_base_tree,
3738     struct got_pathlist_head *commitable_paths,
3739     got_worktree_status_cb status_cb, void *status_arg,
3740     struct got_repository *repo)
3741 {
3742 	const struct got_error *err = NULL;
3743 	struct got_tree_entry *new_te;
3744 	char *subtree_path;
3745 
3746 	*new_tep = NULL;
3747 
3748 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
3749 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
3750 	    child_path) == -1)
3751 		return got_error_from_errno("asprintf");
3752 
3753 	new_te = calloc(1, sizeof(*new_te));
3754 	if (new_te == NULL)
3755 		return got_error_from_errno("calloc");
3756 	new_te->mode = S_IFDIR;
3757 	new_te->name = strdup(child_path);
3758 	if (new_te->name == NULL) {
3759 		err = got_error_from_errno("strdup");
3760 		got_object_tree_entry_close(new_te);
3761 		goto done;
3762 	}
3763 	err = write_tree(&new_te->id, NULL, subtree_path,
3764 	    commitable_paths, status_cb, status_arg, repo);
3765 	if (err) {
3766 		got_object_tree_entry_close(new_te);
3767 		goto done;
3768 	}
3769 done:
3770 	free(subtree_path);
3771 	if (err == NULL)
3772 		*new_tep = new_te;
3773 	return err;
3774 }
3775 
3776 static const struct got_error *
3777 write_tree(struct got_object_id **new_tree_id,
3778     struct got_tree_object *base_tree, const char *path_base_tree,
3779     struct got_pathlist_head *commitable_paths,
3780     got_worktree_status_cb status_cb, void *status_arg,
3781     struct got_repository *repo)
3782 {
3783 	const struct got_error *err = NULL;
3784 	const struct got_tree_entries *base_entries = NULL;
3785 	struct got_pathlist_head paths;
3786 	struct got_tree_entries new_tree_entries;
3787 	struct got_tree_entry *te, *new_te = NULL;
3788 	struct got_pathlist_entry *pe;
3789 
3790 	TAILQ_INIT(&paths);
3791 	new_tree_entries.nentries = 0;
3792 	SIMPLEQ_INIT(&new_tree_entries.head);
3793 
3794 	/* Insert, and recurse into, newly added entries first. */
3795 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3796 		struct got_commitable *ct = pe->data;
3797 		char *child_path = NULL, *slash;
3798 
3799 		if ((ct->status != GOT_STATUS_ADD &&
3800 		    ct->staged_status != GOT_STATUS_ADD) ||
3801 		    (ct->flags & GOT_COMMITABLE_ADDED))
3802 			continue;
3803 
3804 		 if (!got_path_is_child(pe->path, path_base_tree,
3805 		     strlen(path_base_tree)))
3806 			continue;
3807 
3808 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
3809 		    pe->path);
3810 		if (err)
3811 			goto done;
3812 
3813 		slash = strchr(child_path, '/');
3814 		if (slash == NULL) {
3815 			err = alloc_added_blob_tree_entry(&new_te, ct);
3816 			if (err)
3817 				goto done;
3818 			err = report_ct_status(ct, status_cb, status_arg);
3819 			if (err)
3820 				goto done;
3821 			ct->flags |= GOT_COMMITABLE_ADDED;
3822 			err = insert_tree_entry(new_te, &paths);
3823 			if (err)
3824 				goto done;
3825 		} else {
3826 			*slash = '\0'; /* trim trailing path components */
3827 			if (base_tree == NULL ||
3828 			    got_object_tree_find_entry(base_tree, child_path)
3829 			    == NULL) {
3830 				err = make_subtree_for_added_blob(&new_te,
3831 				    child_path, path_base_tree,
3832 				    commitable_paths, status_cb, status_arg,
3833 				    repo);
3834 				if (err)
3835 					goto done;
3836 				err = insert_tree_entry(new_te, &paths);
3837 				if (err)
3838 					goto done;
3839 			}
3840 		}
3841 	}
3842 
3843 	if (base_tree) {
3844 		/* Handle modified and deleted entries. */
3845 		base_entries = got_object_tree_get_entries(base_tree);
3846 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
3847 			struct got_commitable *ct = NULL;
3848 
3849 			if (got_object_tree_entry_is_submodule(te)) {
3850 				/* Entry is a submodule; just copy it. */
3851 				err = got_object_tree_entry_dup(&new_te, te);
3852 				if (err)
3853 					goto done;
3854 				err = insert_tree_entry(new_te, &paths);
3855 				if (err)
3856 					goto done;
3857 				continue;
3858 			}
3859 
3860 			if (S_ISDIR(te->mode)) {
3861 				int modified;
3862 				err = got_object_tree_entry_dup(&new_te, te);
3863 				if (err)
3864 					goto done;
3865 				err = match_modified_subtree(&modified, te,
3866 				    path_base_tree, commitable_paths);
3867 				if (err)
3868 					goto done;
3869 				/* Avoid recursion into unmodified subtrees. */
3870 				if (modified) {
3871 					free(new_te->id);
3872 					err = write_subtree(&new_te->id, te,
3873 					    path_base_tree, commitable_paths,
3874 					    status_cb, status_arg, repo);
3875 					if (err)
3876 						goto done;
3877 				}
3878 				err = insert_tree_entry(new_te, &paths);
3879 				if (err)
3880 					goto done;
3881 				continue;
3882 			}
3883 
3884 			err = match_deleted_or_modified_ct(&ct, te,
3885 			    path_base_tree, commitable_paths);
3886 			if (err)
3887 				goto done;
3888 			if (ct) {
3889 				/* NB: Deleted entries get dropped here. */
3890 				if (ct->status == GOT_STATUS_MODIFY ||
3891 				    ct->staged_status == GOT_STATUS_MODIFY) {
3892 					err = alloc_modified_blob_tree_entry(
3893 					    &new_te, te, ct);
3894 					if (err)
3895 						goto done;
3896 					err = insert_tree_entry(new_te, &paths);
3897 					if (err)
3898 						goto done;
3899 				}
3900 				err = report_ct_status(ct, status_cb,
3901 				    status_arg);
3902 				if (err)
3903 					goto done;
3904 			} else {
3905 				/* Entry is unchanged; just copy it. */
3906 				err = got_object_tree_entry_dup(&new_te, te);
3907 				if (err)
3908 					goto done;
3909 				err = insert_tree_entry(new_te, &paths);
3910 				if (err)
3911 					goto done;
3912 			}
3913 		}
3914 	}
3915 
3916 	/* Write new list of entries; deleted entries have been dropped. */
3917 	TAILQ_FOREACH(pe, &paths, entry) {
3918 		struct got_tree_entry *te = pe->data;
3919 		new_tree_entries.nentries++;
3920 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
3921 	}
3922 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
3923 done:
3924 	got_object_tree_entries_close(&new_tree_entries);
3925 	got_pathlist_free(&paths);
3926 	return err;
3927 }
3928 
3929 static const struct got_error *
3930 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
3931     struct got_object_id *new_base_commit_id, struct got_fileindex *fileindex,
3932     int have_staged_files)
3933 {
3934 	const struct got_error *err = NULL;
3935 	struct got_pathlist_entry *pe;
3936 
3937 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3938 		struct got_fileindex_entry *ie;
3939 		struct got_commitable *ct = pe->data;
3940 
3941 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
3942 		if (ie) {
3943 			if (ct->status == GOT_STATUS_DELETE ||
3944 			    ct->staged_status == GOT_STATUS_DELETE) {
3945 				got_fileindex_entry_remove(fileindex, ie);
3946 				got_fileindex_entry_free(ie);
3947 			} else if (ct->staged_status == GOT_STATUS_ADD ||
3948 			    ct->staged_status == GOT_STATUS_MODIFY) {
3949 				got_fileindex_entry_stage_set(ie,
3950 				    GOT_FILEIDX_STAGE_NONE);
3951 				err = got_fileindex_entry_update(ie,
3952 				    ct->ondisk_path, ct->staged_blob_id->sha1,
3953 				    new_base_commit_id->sha1,
3954 				    !have_staged_files);
3955 			} else
3956 				err = got_fileindex_entry_update(ie,
3957 				    ct->ondisk_path, ct->blob_id->sha1,
3958 				    new_base_commit_id->sha1,
3959 				    !have_staged_files);
3960 		} else {
3961 			err = got_fileindex_entry_alloc(&ie,
3962 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
3963 			    new_base_commit_id->sha1);
3964 			if (err)
3965 				break;
3966 			err = got_fileindex_entry_add(fileindex, ie);
3967 			if (err)
3968 				break;
3969 		}
3970 	}
3971 	return err;
3972 }
3973 
3974 
3975 static const struct got_error *
3976 check_out_of_date(const char *in_repo_path, unsigned char status,
3977     unsigned char staged_status, struct got_object_id *base_blob_id,
3978     struct got_object_id *base_commit_id,
3979     struct got_object_id *head_commit_id, struct got_repository *repo,
3980     int ood_errcode)
3981 {
3982 	const struct got_error *err = NULL;
3983 	struct got_object_id *id = NULL;
3984 
3985 	if (status != GOT_STATUS_ADD && staged_status != GOT_STATUS_ADD) {
3986 		/* Trivial case: base commit == head commit */
3987 		if (got_object_id_cmp(base_commit_id, head_commit_id) == 0)
3988 			return NULL;
3989 		/*
3990 		 * Ensure file content which local changes were based
3991 		 * on matches file content in the branch head.
3992 		 */
3993 		err = got_object_id_by_path(&id, repo, head_commit_id,
3994 		    in_repo_path);
3995 		if (err) {
3996 			if (err->code == GOT_ERR_NO_TREE_ENTRY)
3997 				err = got_error(ood_errcode);
3998 			goto done;
3999 		} else if (got_object_id_cmp(id, base_blob_id) != 0)
4000 			err = got_error(ood_errcode);
4001 	} else {
4002 		/* Require that added files don't exist in the branch head. */
4003 		err = got_object_id_by_path(&id, repo, head_commit_id,
4004 		    in_repo_path);
4005 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
4006 			goto done;
4007 		err = id ? got_error(ood_errcode) : NULL;
4008 	}
4009 done:
4010 	free(id);
4011 	return err;
4012 }
4013 
4014 const struct got_error *
4015 commit_worktree(struct got_object_id **new_commit_id,
4016     struct got_pathlist_head *commitable_paths,
4017     struct got_object_id *head_commit_id, struct got_worktree *worktree,
4018     const char *author, const char *committer,
4019     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
4020     got_worktree_status_cb status_cb, void *status_arg,
4021     struct got_repository *repo)
4022 {
4023 	const struct got_error *err = NULL, *unlockerr = NULL;
4024 	struct got_pathlist_entry *pe;
4025 	const char *head_ref_name = NULL;
4026 	struct got_commit_object *head_commit = NULL;
4027 	struct got_reference *head_ref2 = NULL;
4028 	struct got_object_id *head_commit_id2 = NULL;
4029 	struct got_tree_object *head_tree = NULL;
4030 	struct got_object_id *new_tree_id = NULL;
4031 	struct got_object_id_queue parent_ids;
4032 	struct got_object_qid *pid = NULL;
4033 	char *logmsg = NULL;
4034 
4035 	*new_commit_id = NULL;
4036 
4037 	SIMPLEQ_INIT(&parent_ids);
4038 
4039 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
4040 	if (err)
4041 		goto done;
4042 
4043 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
4044 	if (err)
4045 		goto done;
4046 
4047 	if (commit_msg_cb != NULL) {
4048 		err = commit_msg_cb(commitable_paths, &logmsg, commit_arg);
4049 		if (err)
4050 			goto done;
4051 	}
4052 
4053 	if (logmsg == NULL || strlen(logmsg) == 0) {
4054 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
4055 		goto done;
4056 	}
4057 
4058 	/* Create blobs from added and modified files and record their IDs. */
4059 	TAILQ_FOREACH(pe, commitable_paths, entry) {
4060 		struct got_commitable *ct = pe->data;
4061 		char *ondisk_path;
4062 
4063 		/* Blobs for staged files already exist. */
4064 		if (ct->staged_status == GOT_STATUS_ADD ||
4065 		    ct->staged_status == GOT_STATUS_MODIFY)
4066 			continue;
4067 
4068 		if (ct->status != GOT_STATUS_ADD &&
4069 		    ct->status != GOT_STATUS_MODIFY)
4070 			continue;
4071 
4072 		if (asprintf(&ondisk_path, "%s/%s",
4073 		    worktree->root_path, pe->path) == -1) {
4074 			err = got_error_from_errno("asprintf");
4075 			goto done;
4076 		}
4077 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
4078 		free(ondisk_path);
4079 		if (err)
4080 			goto done;
4081 	}
4082 
4083 	/* Recursively write new tree objects. */
4084 	err = write_tree(&new_tree_id, head_tree, "/", commitable_paths,
4085 	    status_cb, status_arg, repo);
4086 	if (err)
4087 		goto done;
4088 
4089 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
4090 	if (err)
4091 		goto done;
4092 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
4093 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
4094 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
4095 	got_object_qid_free(pid);
4096 	if (logmsg != NULL)
4097 		free(logmsg);
4098 	if (err)
4099 		goto done;
4100 
4101 	/* Check if a concurrent commit to our branch has occurred. */
4102 	head_ref_name = got_worktree_get_head_ref_name(worktree);
4103 	if (head_ref_name == NULL) {
4104 		err = got_error_from_errno("got_worktree_get_head_ref_name");
4105 		goto done;
4106 	}
4107 	/* Lock the reference here to prevent concurrent modification. */
4108 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
4109 	if (err)
4110 		goto done;
4111 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
4112 	if (err)
4113 		goto done;
4114 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
4115 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
4116 		goto done;
4117 	}
4118 	/* Update branch head in repository. */
4119 	err = got_ref_change_ref(head_ref2, *new_commit_id);
4120 	if (err)
4121 		goto done;
4122 	err = got_ref_write(head_ref2, repo);
4123 	if (err)
4124 		goto done;
4125 
4126 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
4127 	if (err)
4128 		goto done;
4129 
4130 	err = ref_base_commit(worktree, repo);
4131 	if (err)
4132 		goto done;
4133 done:
4134 	if (head_tree)
4135 		got_object_tree_close(head_tree);
4136 	if (head_commit)
4137 		got_object_commit_close(head_commit);
4138 	free(head_commit_id2);
4139 	if (head_ref2) {
4140 		unlockerr = got_ref_unlock(head_ref2);
4141 		if (unlockerr && err == NULL)
4142 			err = unlockerr;
4143 		got_ref_close(head_ref2);
4144 	}
4145 	return err;
4146 }
4147 
4148 static const struct got_error *
4149 check_path_is_commitable(const char *path,
4150     struct got_pathlist_head *commitable_paths)
4151 {
4152 	struct got_pathlist_entry *cpe = NULL;
4153 	size_t path_len = strlen(path);
4154 
4155 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
4156 		struct got_commitable *ct = cpe->data;
4157 		const char *ct_path = ct->path;
4158 
4159 		while (ct_path[0] == '/')
4160 			ct_path++;
4161 
4162 		if (strcmp(path, ct_path) == 0 ||
4163 		    got_path_is_child(ct_path, path, path_len))
4164 			break;
4165 	}
4166 
4167 	if (cpe == NULL)
4168 		return got_error_path(path, GOT_ERR_BAD_PATH);
4169 
4170 	return NULL;
4171 }
4172 
4173 static const struct got_error *
4174 check_staged_file(void *arg, struct got_fileindex_entry *ie)
4175 {
4176 	int *have_staged_files = arg;
4177 
4178 	if (got_fileindex_entry_stage_get(ie) != GOT_FILEIDX_STAGE_NONE) {
4179 		*have_staged_files = 1;
4180 		return got_error(GOT_ERR_CANCELLED);
4181 	}
4182 
4183 	return NULL;
4184 }
4185 
4186 static const struct got_error *
4187 check_non_staged_files(struct got_fileindex *fileindex,
4188     struct got_pathlist_head *paths)
4189 {
4190 	struct got_pathlist_entry *pe;
4191 	struct got_fileindex_entry *ie;
4192 
4193 	TAILQ_FOREACH(pe, paths, entry) {
4194 		if (pe->path[0] == '\0')
4195 			continue;
4196 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
4197 		if (ie == NULL)
4198 			return got_error_path(pe->path, GOT_ERR_BAD_PATH);
4199 		if (got_fileindex_entry_stage_get(ie) == GOT_FILEIDX_STAGE_NONE)
4200 			return got_error_path(pe->path,
4201 			    GOT_ERR_FILE_NOT_STAGED);
4202 	}
4203 
4204 	return NULL;
4205 }
4206 
4207 const struct got_error *
4208 got_worktree_commit(struct got_object_id **new_commit_id,
4209     struct got_worktree *worktree, struct got_pathlist_head *paths,
4210     const char *author, const char *committer,
4211     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
4212     got_worktree_status_cb status_cb, void *status_arg,
4213     struct got_repository *repo)
4214 {
4215 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
4216 	struct got_fileindex *fileindex = NULL;
4217 	char *fileindex_path = NULL;
4218 	struct got_pathlist_head commitable_paths;
4219 	struct collect_commitables_arg cc_arg;
4220 	struct got_pathlist_entry *pe;
4221 	struct got_reference *head_ref = NULL;
4222 	struct got_object_id *head_commit_id = NULL;
4223 	int have_staged_files = 0;
4224 
4225 	*new_commit_id = NULL;
4226 
4227 	TAILQ_INIT(&commitable_paths);
4228 
4229 	err = lock_worktree(worktree, LOCK_EX);
4230 	if (err)
4231 		goto done;
4232 
4233 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
4234 	if (err)
4235 		goto done;
4236 
4237 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
4238 	if (err)
4239 		goto done;
4240 
4241 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4242 	if (err)
4243 		goto done;
4244 
4245 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
4246 	    &have_staged_files);
4247 	if (err && err->code != GOT_ERR_CANCELLED)
4248 		goto done;
4249 	if (have_staged_files) {
4250 		err = check_non_staged_files(fileindex, paths);
4251 		if (err)
4252 			goto done;
4253 	}
4254 
4255 	cc_arg.commitable_paths = &commitable_paths;
4256 	cc_arg.worktree = worktree;
4257 	cc_arg.repo = repo;
4258 	cc_arg.have_staged_files = have_staged_files;
4259 	TAILQ_FOREACH(pe, paths, entry) {
4260 		err = worktree_status(worktree, pe->path, fileindex, repo,
4261 		    collect_commitables, &cc_arg, NULL, NULL);
4262 		if (err)
4263 			goto done;
4264 	}
4265 
4266 	if (TAILQ_EMPTY(&commitable_paths)) {
4267 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
4268 		goto done;
4269 	}
4270 
4271 	TAILQ_FOREACH(pe, paths, entry) {
4272 		err = check_path_is_commitable(pe->path, &commitable_paths);
4273 		if (err)
4274 			goto done;
4275 	}
4276 
4277 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
4278 		struct got_commitable *ct = pe->data;
4279 		const char *ct_path = ct->in_repo_path;
4280 
4281 		while (ct_path[0] == '/')
4282 			ct_path++;
4283 		err = check_out_of_date(ct_path, ct->status,
4284 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
4285 		    head_commit_id, repo, GOT_ERR_COMMIT_OUT_OF_DATE);
4286 		if (err)
4287 			goto done;
4288 
4289 	}
4290 
4291 	err = commit_worktree(new_commit_id, &commitable_paths,
4292 	    head_commit_id, worktree, author, committer,
4293 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
4294 	if (err)
4295 		goto done;
4296 
4297 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
4298 	    fileindex, have_staged_files);
4299 	sync_err = sync_fileindex(fileindex, fileindex_path);
4300 	if (sync_err && err == NULL)
4301 		err = sync_err;
4302 done:
4303 	if (fileindex)
4304 		got_fileindex_free(fileindex);
4305 	free(fileindex_path);
4306 	unlockerr = lock_worktree(worktree, LOCK_SH);
4307 	if (unlockerr && err == NULL)
4308 		err = unlockerr;
4309 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
4310 		struct got_commitable *ct = pe->data;
4311 		free_commitable(ct);
4312 	}
4313 	got_pathlist_free(&commitable_paths);
4314 	return err;
4315 }
4316 
4317 const char *
4318 got_commitable_get_path(struct got_commitable *ct)
4319 {
4320 	return ct->path;
4321 }
4322 
4323 unsigned int
4324 got_commitable_get_status(struct got_commitable *ct)
4325 {
4326 	return ct->status;
4327 }
4328 
4329 struct check_rebase_ok_arg {
4330 	struct got_worktree *worktree;
4331 	struct got_repository *repo;
4332 };
4333 
4334 static const struct got_error *
4335 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
4336 {
4337 	const struct got_error *err = NULL;
4338 	struct check_rebase_ok_arg *a = arg;
4339 	unsigned char status;
4340 	struct stat sb;
4341 	char *ondisk_path;
4342 
4343 	/* Reject rebase of a work tree with mixed base commits. */
4344 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
4345 	    SHA1_DIGEST_LENGTH))
4346 		return got_error(GOT_ERR_MIXED_COMMITS);
4347 
4348 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
4349 	    == -1)
4350 		return got_error_from_errno("asprintf");
4351 
4352 	/* Reject rebase of a work tree with modified or staged files. */
4353 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
4354 	free(ondisk_path);
4355 	if (err)
4356 		return err;
4357 
4358 	if (status != GOT_STATUS_NO_CHANGE)
4359 		return got_error(GOT_ERR_MODIFIED);
4360 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
4361 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
4362 
4363 	return NULL;
4364 }
4365 
4366 const struct got_error *
4367 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
4368     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
4369     struct got_worktree *worktree, struct got_reference *branch,
4370     struct got_repository *repo)
4371 {
4372 	const struct got_error *err = NULL;
4373 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
4374 	char *branch_ref_name = NULL;
4375 	char *fileindex_path = NULL;
4376 	struct check_rebase_ok_arg ok_arg;
4377 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
4378 
4379 	*new_base_branch_ref = NULL;
4380 	*tmp_branch = NULL;
4381 	*fileindex = NULL;
4382 
4383 	err = lock_worktree(worktree, LOCK_EX);
4384 	if (err)
4385 		return err;
4386 
4387 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4388 	if (err)
4389 		goto done;
4390 
4391 	ok_arg.worktree = worktree;
4392 	ok_arg.repo = repo;
4393 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
4394 	    &ok_arg);
4395 	if (err)
4396 		goto done;
4397 
4398 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4399 	if (err)
4400 		goto done;
4401 
4402 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
4403 	if (err)
4404 		goto done;
4405 
4406 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
4407 	if (err)
4408 		goto done;
4409 
4410 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
4411 	    0);
4412 	if (err)
4413 		goto done;
4414 
4415 	err = got_ref_alloc_symref(new_base_branch_ref,
4416 	    new_base_branch_ref_name, wt_branch);
4417 	if (err)
4418 		goto done;
4419 	err = got_ref_write(*new_base_branch_ref, repo);
4420 	if (err)
4421 		goto done;
4422 
4423 	/* TODO Lock original branch's ref while rebasing? */
4424 
4425 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
4426 	if (err)
4427 		goto done;
4428 
4429 	err = got_ref_write(branch_ref, repo);
4430 	if (err)
4431 		goto done;
4432 
4433 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
4434 	    worktree->base_commit_id);
4435 	if (err)
4436 		goto done;
4437 	err = got_ref_write(*tmp_branch, repo);
4438 	if (err)
4439 		goto done;
4440 
4441 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
4442 	if (err)
4443 		goto done;
4444 done:
4445 	free(fileindex_path);
4446 	free(tmp_branch_name);
4447 	free(new_base_branch_ref_name);
4448 	free(branch_ref_name);
4449 	if (branch_ref)
4450 		got_ref_close(branch_ref);
4451 	if (wt_branch)
4452 		got_ref_close(wt_branch);
4453 	if (err) {
4454 		if (*new_base_branch_ref) {
4455 			got_ref_close(*new_base_branch_ref);
4456 			*new_base_branch_ref = NULL;
4457 		}
4458 		if (*tmp_branch) {
4459 			got_ref_close(*tmp_branch);
4460 			*tmp_branch = NULL;
4461 		}
4462 		if (*fileindex) {
4463 			got_fileindex_free(*fileindex);
4464 			*fileindex = NULL;
4465 		}
4466 		lock_worktree(worktree, LOCK_SH);
4467 	}
4468 	return err;
4469 }
4470 
4471 const struct got_error *
4472 got_worktree_rebase_continue(struct got_object_id **commit_id,
4473     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
4474     struct got_reference **branch, struct got_fileindex **fileindex,
4475     struct got_worktree *worktree, struct got_repository *repo)
4476 {
4477 	const struct got_error *err;
4478 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
4479 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
4480 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
4481 	char *fileindex_path = NULL;
4482 	int have_staged_files = 0;
4483 
4484 	*commit_id = NULL;
4485 	*new_base_branch = NULL;
4486 	*tmp_branch = NULL;
4487 	*branch = NULL;
4488 	*fileindex = NULL;
4489 
4490 	err = lock_worktree(worktree, LOCK_EX);
4491 	if (err)
4492 		return err;
4493 
4494 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4495 	if (err)
4496 		goto done;
4497 
4498 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
4499 	    &have_staged_files);
4500 	if (err && err->code != GOT_ERR_CANCELLED)
4501 		goto done;
4502 	if (have_staged_files) {
4503 		err = got_error(GOT_ERR_STAGED_PATHS);
4504 		goto done;
4505 	}
4506 
4507 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4508 	if (err)
4509 		goto done;
4510 
4511 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
4512 	if (err)
4513 		goto done;
4514 
4515 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4516 	if (err)
4517 		goto done;
4518 
4519 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
4520 	if (err)
4521 		goto done;
4522 
4523 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
4524 	if (err)
4525 		goto done;
4526 
4527 	err = got_ref_open(branch, repo,
4528 	    got_ref_get_symref_target(branch_ref), 0);
4529 	if (err)
4530 		goto done;
4531 
4532 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4533 	if (err)
4534 		goto done;
4535 
4536 	err = got_ref_resolve(commit_id, repo, commit_ref);
4537 	if (err)
4538 		goto done;
4539 
4540 	err = got_ref_open(new_base_branch, repo,
4541 	    new_base_branch_ref_name, 0);
4542 	if (err)
4543 		goto done;
4544 
4545 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
4546 	if (err)
4547 		goto done;
4548 done:
4549 	free(commit_ref_name);
4550 	free(branch_ref_name);
4551 	free(fileindex_path);
4552 	if (commit_ref)
4553 		got_ref_close(commit_ref);
4554 	if (branch_ref)
4555 		got_ref_close(branch_ref);
4556 	if (err) {
4557 		free(*commit_id);
4558 		*commit_id = NULL;
4559 		if (*tmp_branch) {
4560 			got_ref_close(*tmp_branch);
4561 			*tmp_branch = NULL;
4562 		}
4563 		if (*new_base_branch) {
4564 			got_ref_close(*new_base_branch);
4565 			*new_base_branch = NULL;
4566 		}
4567 		if (*branch) {
4568 			got_ref_close(*branch);
4569 			*branch = NULL;
4570 		}
4571 		if (*fileindex) {
4572 			got_fileindex_free(*fileindex);
4573 			*fileindex = NULL;
4574 		}
4575 		lock_worktree(worktree, LOCK_SH);
4576 	}
4577 	return err;
4578 }
4579 
4580 const struct got_error *
4581 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
4582 {
4583 	const struct got_error *err;
4584 	char *tmp_branch_name = NULL;
4585 
4586 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4587 	if (err)
4588 		return err;
4589 
4590 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
4591 	free(tmp_branch_name);
4592 	return NULL;
4593 }
4594 
4595 static const struct got_error *
4596 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
4597     char **logmsg, void *arg)
4598 {
4599 	*logmsg = arg;
4600 	return NULL;
4601 }
4602 
4603 static const struct got_error *
4604 rebase_status(void *arg, unsigned char status, unsigned char staged_status,
4605     const char *path, struct got_object_id *blob_id,
4606     struct got_object_id *staged_blob_id, struct got_object_id *commit_id)
4607 {
4608 	return NULL;
4609 }
4610 
4611 struct collect_merged_paths_arg {
4612 	got_worktree_checkout_cb progress_cb;
4613 	void *progress_arg;
4614 	struct got_pathlist_head *merged_paths;
4615 };
4616 
4617 static const struct got_error *
4618 collect_merged_paths(void *arg, unsigned char status, const char *path)
4619 {
4620 	const struct got_error *err;
4621 	struct collect_merged_paths_arg *a = arg;
4622 	char *p;
4623 	struct got_pathlist_entry *new;
4624 
4625 	err = (*a->progress_cb)(a->progress_arg, status, path);
4626 	if (err)
4627 		return err;
4628 
4629 	if (status != GOT_STATUS_MERGE &&
4630 	    status != GOT_STATUS_ADD &&
4631 	    status != GOT_STATUS_DELETE &&
4632 	    status != GOT_STATUS_CONFLICT)
4633 		return NULL;
4634 
4635 	p = strdup(path);
4636 	if (p == NULL)
4637 		return got_error_from_errno("strdup");
4638 
4639 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
4640 	if (err || new == NULL)
4641 		free(p);
4642 	return err;
4643 }
4644 
4645 void
4646 got_worktree_rebase_pathlist_free(struct got_pathlist_head *merged_paths)
4647 {
4648 	struct got_pathlist_entry *pe;
4649 
4650 	TAILQ_FOREACH(pe, merged_paths, entry)
4651 		free((char *)pe->path);
4652 
4653 	got_pathlist_free(merged_paths);
4654 }
4655 
4656 static const struct got_error *
4657 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
4658     struct got_repository *repo)
4659 {
4660 	const struct got_error *err;
4661 	struct got_reference *commit_ref = NULL;
4662 
4663 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4664 	if (err) {
4665 		if (err->code != GOT_ERR_NOT_REF)
4666 			goto done;
4667 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
4668 		if (err)
4669 			goto done;
4670 		err = got_ref_write(commit_ref, repo);
4671 		if (err)
4672 			goto done;
4673 	} else {
4674 		struct got_object_id *stored_id;
4675 		int cmp;
4676 
4677 		err = got_ref_resolve(&stored_id, repo, commit_ref);
4678 		if (err)
4679 			goto done;
4680 		cmp = got_object_id_cmp(commit_id, stored_id);
4681 		free(stored_id);
4682 		if (cmp != 0) {
4683 			err = got_error(GOT_ERR_REBASE_COMMITID);
4684 			goto done;
4685 		}
4686 	}
4687 done:
4688 	if (commit_ref)
4689 		got_ref_close(commit_ref);
4690 	return err;
4691 }
4692 
4693 static const struct got_error *
4694 rebase_merge_files(struct got_pathlist_head *merged_paths,
4695     const char *commit_ref_name, struct got_worktree *worktree,
4696     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
4697     struct got_object_id *commit_id, struct got_repository *repo,
4698     got_worktree_checkout_cb progress_cb, void *progress_arg,
4699     got_cancel_cb cancel_cb, void *cancel_arg)
4700 {
4701 	const struct got_error *err;
4702 	struct got_reference *commit_ref = NULL;
4703 	struct collect_merged_paths_arg cmp_arg;
4704 	char *fileindex_path;
4705 
4706 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
4707 
4708 	err = get_fileindex_path(&fileindex_path, worktree);
4709 	if (err)
4710 		return err;
4711 
4712 	cmp_arg.progress_cb = progress_cb;
4713 	cmp_arg.progress_arg = progress_arg;
4714 	cmp_arg.merged_paths = merged_paths;
4715 	err = merge_files(worktree, fileindex, fileindex_path,
4716 	    parent_commit_id, commit_id, repo, collect_merged_paths,
4717 	    &cmp_arg, cancel_cb, cancel_arg);
4718 	if (commit_ref)
4719 		got_ref_close(commit_ref);
4720 	return err;
4721 }
4722 
4723 const struct got_error *
4724 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
4725     struct got_worktree *worktree, struct got_fileindex *fileindex,
4726     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
4727     struct got_repository *repo,
4728     got_worktree_checkout_cb progress_cb, void *progress_arg,
4729     got_cancel_cb cancel_cb, void *cancel_arg)
4730 {
4731 	const struct got_error *err;
4732 	char *commit_ref_name;
4733 
4734 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4735 	if (err)
4736 		return err;
4737 
4738 	err = store_commit_id(commit_ref_name, commit_id, repo);
4739 	if (err)
4740 		goto done;
4741 
4742 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4743 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4744 	    progress_arg, cancel_cb, cancel_arg);
4745 done:
4746 	free(commit_ref_name);
4747 	return err;
4748 }
4749 
4750 const struct got_error *
4751 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
4752     struct got_worktree *worktree, struct got_fileindex *fileindex,
4753     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
4754     struct got_repository *repo,
4755     got_worktree_checkout_cb progress_cb, void *progress_arg,
4756     got_cancel_cb cancel_cb, void *cancel_arg)
4757 {
4758 	const struct got_error *err;
4759 	char *commit_ref_name;
4760 
4761 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4762 	if (err)
4763 		return err;
4764 
4765 	err = store_commit_id(commit_ref_name, commit_id, repo);
4766 	if (err)
4767 		goto done;
4768 
4769 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4770 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4771 	    progress_arg, cancel_cb, cancel_arg);
4772 done:
4773 	free(commit_ref_name);
4774 	return err;
4775 }
4776 
4777 static const struct got_error *
4778 rebase_commit(struct got_object_id **new_commit_id,
4779     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
4780     struct got_worktree *worktree, struct got_fileindex *fileindex,
4781     struct got_reference *tmp_branch, struct got_commit_object *orig_commit,
4782     const char *new_logmsg, struct got_repository *repo)
4783 {
4784 	const struct got_error *err, *sync_err;
4785 	struct got_pathlist_head commitable_paths;
4786 	struct collect_commitables_arg cc_arg;
4787 	char *fileindex_path = NULL;
4788 	struct got_reference *head_ref = NULL;
4789 	struct got_object_id *head_commit_id = NULL;
4790 	char *logmsg = NULL;
4791 
4792 	TAILQ_INIT(&commitable_paths);
4793 	*new_commit_id = NULL;
4794 
4795 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
4796 
4797 	err = get_fileindex_path(&fileindex_path, worktree);
4798 	if (err)
4799 		return err;
4800 
4801 	cc_arg.commitable_paths = &commitable_paths;
4802 	cc_arg.worktree = worktree;
4803 	cc_arg.repo = repo;
4804 	cc_arg.have_staged_files = 0;
4805 	/*
4806 	 * If possible get the status of individual files directly to
4807 	 * avoid crawling the entire work tree once per rebased commit.
4808 	 * TODO: Ideally, merged_paths would contain a list of commitables
4809 	 * we could use so we could skip worktree_status() entirely.
4810 	 */
4811 	if (merged_paths) {
4812 		struct got_pathlist_entry *pe;
4813 		if (TAILQ_EMPTY(merged_paths)) {
4814 			err = got_error(GOT_ERR_NO_MERGED_PATHS);
4815 			goto done;
4816 		}
4817 		TAILQ_FOREACH(pe, merged_paths, entry) {
4818 			err = worktree_status(worktree, pe->path, fileindex,
4819 			    repo, collect_commitables, &cc_arg, NULL, NULL);
4820 			if (err)
4821 				goto done;
4822 		}
4823 	} else {
4824 		err = worktree_status(worktree, "", fileindex, repo,
4825 		    collect_commitables, &cc_arg, NULL, NULL);
4826 		if (err)
4827 			goto done;
4828 	}
4829 
4830 	if (TAILQ_EMPTY(&commitable_paths)) {
4831 		/* No-op change; commit will be elided. */
4832 		err = got_ref_delete(commit_ref, repo);
4833 		if (err)
4834 			goto done;
4835 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
4836 		goto done;
4837 	}
4838 
4839 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
4840 	if (err)
4841 		goto done;
4842 
4843 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
4844 	if (err)
4845 		goto done;
4846 
4847 	if (new_logmsg) {
4848 		logmsg = strdup(new_logmsg);
4849 		if (logmsg == NULL) {
4850 			err = got_error_from_errno("strdup");
4851 			goto done;
4852 		}
4853 	} else {
4854 		err = got_object_commit_get_logmsg(&logmsg, orig_commit);
4855 		if (err)
4856 			goto done;
4857 	}
4858 
4859 	/* NB: commit_worktree will call free(logmsg) */
4860 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
4861 	    worktree, got_object_commit_get_author(orig_commit),
4862 	    got_object_commit_get_committer(orig_commit),
4863 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
4864 	if (err)
4865 		goto done;
4866 
4867 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
4868 	if (err)
4869 		goto done;
4870 
4871 	err = got_ref_delete(commit_ref, repo);
4872 	if (err)
4873 		goto done;
4874 
4875 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
4876 	    fileindex, 0);
4877 	sync_err = sync_fileindex(fileindex, fileindex_path);
4878 	if (sync_err && err == NULL)
4879 		err = sync_err;
4880 done:
4881 	free(fileindex_path);
4882 	free(head_commit_id);
4883 	if (head_ref)
4884 		got_ref_close(head_ref);
4885 	if (err) {
4886 		free(*new_commit_id);
4887 		*new_commit_id = NULL;
4888 	}
4889 	return err;
4890 }
4891 
4892 const struct got_error *
4893 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
4894     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4895     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4896     struct got_commit_object *orig_commit,
4897     struct got_object_id *orig_commit_id, struct got_repository *repo)
4898 {
4899 	const struct got_error *err;
4900 	char *commit_ref_name;
4901 	struct got_reference *commit_ref = NULL;
4902 	struct got_object_id *commit_id = NULL;
4903 
4904 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4905 	if (err)
4906 		return err;
4907 
4908 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4909 	if (err)
4910 		goto done;
4911 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4912 	if (err)
4913 		goto done;
4914 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4915 		err = got_error(GOT_ERR_REBASE_COMMITID);
4916 		goto done;
4917 	}
4918 
4919 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4920 	    worktree, fileindex, tmp_branch, orig_commit, NULL, repo);
4921 done:
4922 	if (commit_ref)
4923 		got_ref_close(commit_ref);
4924 	free(commit_ref_name);
4925 	free(commit_id);
4926 	return err;
4927 }
4928 
4929 const struct got_error *
4930 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
4931     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4932     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4933     struct got_commit_object *orig_commit,
4934     struct got_object_id *orig_commit_id, const char *new_logmsg,
4935     struct got_repository *repo)
4936 {
4937 	const struct got_error *err;
4938 	char *commit_ref_name;
4939 	struct got_reference *commit_ref = NULL;
4940 	struct got_object_id *commit_id = NULL;
4941 
4942 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4943 	if (err)
4944 		return err;
4945 
4946 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4947 	if (err)
4948 		goto done;
4949 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4950 	if (err)
4951 		goto done;
4952 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4953 		err = got_error(GOT_ERR_HISTEDIT_COMMITID);
4954 		goto done;
4955 	}
4956 
4957 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4958 	    worktree, fileindex, tmp_branch, orig_commit, new_logmsg, repo);
4959 done:
4960 	if (commit_ref)
4961 		got_ref_close(commit_ref);
4962 	free(commit_ref_name);
4963 	free(commit_id);
4964 	return err;
4965 }
4966 
4967 const struct got_error *
4968 got_worktree_rebase_postpone(struct got_worktree *worktree,
4969     struct got_fileindex *fileindex)
4970 {
4971 	if (fileindex)
4972 		got_fileindex_free(fileindex);
4973 	return lock_worktree(worktree, LOCK_SH);
4974 }
4975 
4976 static const struct got_error *
4977 delete_ref(const char *name, struct got_repository *repo)
4978 {
4979 	const struct got_error *err;
4980 	struct got_reference *ref;
4981 
4982 	err = got_ref_open(&ref, repo, name, 0);
4983 	if (err) {
4984 		if (err->code == GOT_ERR_NOT_REF)
4985 			return NULL;
4986 		return err;
4987 	}
4988 
4989 	err = got_ref_delete(ref, repo);
4990 	got_ref_close(ref);
4991 	return err;
4992 }
4993 
4994 static const struct got_error *
4995 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
4996 {
4997 	const struct got_error *err;
4998 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
4999 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
5000 
5001 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
5002 	if (err)
5003 		goto done;
5004 	err = delete_ref(tmp_branch_name, repo);
5005 	if (err)
5006 		goto done;
5007 
5008 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
5009 	if (err)
5010 		goto done;
5011 	err = delete_ref(new_base_branch_ref_name, repo);
5012 	if (err)
5013 		goto done;
5014 
5015 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
5016 	if (err)
5017 		goto done;
5018 	err = delete_ref(branch_ref_name, repo);
5019 	if (err)
5020 		goto done;
5021 
5022 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
5023 	if (err)
5024 		goto done;
5025 	err = delete_ref(commit_ref_name, repo);
5026 	if (err)
5027 		goto done;
5028 
5029 done:
5030 	free(tmp_branch_name);
5031 	free(new_base_branch_ref_name);
5032 	free(branch_ref_name);
5033 	free(commit_ref_name);
5034 	return err;
5035 }
5036 
5037 const struct got_error *
5038 got_worktree_rebase_complete(struct got_worktree *worktree,
5039     struct got_fileindex *fileindex, struct got_reference *new_base_branch,
5040     struct got_reference *tmp_branch, struct got_reference *rebased_branch,
5041     struct got_repository *repo)
5042 {
5043 	const struct got_error *err, *unlockerr;
5044 	struct got_object_id *new_head_commit_id = NULL;
5045 
5046 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
5047 	if (err)
5048 		return err;
5049 
5050 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
5051 	if (err)
5052 		goto done;
5053 
5054 	err = got_ref_write(rebased_branch, repo);
5055 	if (err)
5056 		goto done;
5057 
5058 	err = got_worktree_set_head_ref(worktree, rebased_branch);
5059 	if (err)
5060 		goto done;
5061 
5062 	err = delete_rebase_refs(worktree, repo);
5063 done:
5064 	if (fileindex)
5065 		got_fileindex_free(fileindex);
5066 	free(new_head_commit_id);
5067 	unlockerr = lock_worktree(worktree, LOCK_SH);
5068 	if (unlockerr && err == NULL)
5069 		err = unlockerr;
5070 	return err;
5071 }
5072 
5073 const struct got_error *
5074 got_worktree_rebase_abort(struct got_worktree *worktree,
5075     struct got_fileindex *fileindex, struct got_repository *repo,
5076     struct got_reference *new_base_branch,
5077      got_worktree_checkout_cb progress_cb, void *progress_arg)
5078 {
5079 	const struct got_error *err, *unlockerr, *sync_err;
5080 	struct got_reference *resolved = NULL;
5081 	struct got_object_id *commit_id = NULL;
5082 	char *fileindex_path = NULL;
5083 	struct revert_file_args rfa;
5084 	struct got_object_id *tree_id = NULL;
5085 
5086 	err = lock_worktree(worktree, LOCK_EX);
5087 	if (err)
5088 		return err;
5089 
5090 	err = got_ref_open(&resolved, repo,
5091 	    got_ref_get_symref_target(new_base_branch), 0);
5092 	if (err)
5093 		goto done;
5094 
5095 	err = got_worktree_set_head_ref(worktree, resolved);
5096 	if (err)
5097 		goto done;
5098 
5099 	/*
5100 	 * XXX commits to the base branch could have happened while
5101 	 * we were busy rebasing; should we store the original commit ID
5102 	 * when rebase begins and read it back here?
5103 	 */
5104 	err = got_ref_resolve(&commit_id, repo, resolved);
5105 	if (err)
5106 		goto done;
5107 
5108 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
5109 	if (err)
5110 		goto done;
5111 
5112 	err = got_object_id_by_path(&tree_id, repo,
5113 	    worktree->base_commit_id, worktree->path_prefix);
5114 	if (err)
5115 		goto done;
5116 
5117 	err = delete_rebase_refs(worktree, repo);
5118 	if (err)
5119 		goto done;
5120 
5121 	err = get_fileindex_path(&fileindex_path, worktree);
5122 	if (err)
5123 		goto done;
5124 
5125 	rfa.worktree = worktree;
5126 	rfa.fileindex = fileindex;
5127 	rfa.progress_cb = progress_cb;
5128 	rfa.progress_arg = progress_arg;
5129 	rfa.patch_cb = NULL;
5130 	rfa.patch_arg = NULL;
5131 	rfa.repo = repo;
5132 	err = worktree_status(worktree, "", fileindex, repo,
5133 	    revert_file, &rfa, NULL, NULL);
5134 	if (err)
5135 		goto sync;
5136 
5137 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
5138 	    repo, progress_cb, progress_arg, NULL, NULL);
5139 sync:
5140 	sync_err = sync_fileindex(fileindex, fileindex_path);
5141 	if (sync_err && err == NULL)
5142 		err = sync_err;
5143 done:
5144 	got_ref_close(resolved);
5145 	free(tree_id);
5146 	free(commit_id);
5147 	if (fileindex)
5148 		got_fileindex_free(fileindex);
5149 	free(fileindex_path);
5150 
5151 	unlockerr = lock_worktree(worktree, LOCK_SH);
5152 	if (unlockerr && err == NULL)
5153 		err = unlockerr;
5154 	return err;
5155 }
5156 
5157 const struct got_error *
5158 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
5159     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
5160     struct got_fileindex **fileindex, struct got_worktree *worktree,
5161     struct got_repository *repo)
5162 {
5163 	const struct got_error *err = NULL;
5164 	char *tmp_branch_name = NULL;
5165 	char *branch_ref_name = NULL;
5166 	char *base_commit_ref_name = NULL;
5167 	char *fileindex_path = NULL;
5168 	struct check_rebase_ok_arg ok_arg;
5169 	struct got_reference *wt_branch = NULL;
5170 	struct got_reference *base_commit_ref = NULL;
5171 
5172 	*tmp_branch = NULL;
5173 	*branch_ref = NULL;
5174 	*base_commit_id = NULL;
5175 	*fileindex = NULL;
5176 
5177 	err = lock_worktree(worktree, LOCK_EX);
5178 	if (err)
5179 		return err;
5180 
5181 	err = open_fileindex(fileindex, &fileindex_path, worktree);
5182 	if (err)
5183 		goto done;
5184 
5185 	ok_arg.worktree = worktree;
5186 	ok_arg.repo = repo;
5187 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
5188 	    &ok_arg);
5189 	if (err)
5190 		goto done;
5191 
5192 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
5193 	if (err)
5194 		goto done;
5195 
5196 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
5197 	if (err)
5198 		goto done;
5199 
5200 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
5201 	    worktree);
5202 	if (err)
5203 		goto done;
5204 
5205 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
5206 	    0);
5207 	if (err)
5208 		goto done;
5209 
5210 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
5211 	if (err)
5212 		goto done;
5213 
5214 	err = got_ref_write(*branch_ref, repo);
5215 	if (err)
5216 		goto done;
5217 
5218 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
5219 	    worktree->base_commit_id);
5220 	if (err)
5221 		goto done;
5222 	err = got_ref_write(base_commit_ref, repo);
5223 	if (err)
5224 		goto done;
5225 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
5226 	if (*base_commit_id == NULL) {
5227 		err = got_error_from_errno("got_object_id_dup");
5228 		goto done;
5229 	}
5230 
5231 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
5232 	    worktree->base_commit_id);
5233 	if (err)
5234 		goto done;
5235 	err = got_ref_write(*tmp_branch, repo);
5236 	if (err)
5237 		goto done;
5238 
5239 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
5240 	if (err)
5241 		goto done;
5242 done:
5243 	free(fileindex_path);
5244 	free(tmp_branch_name);
5245 	free(branch_ref_name);
5246 	free(base_commit_ref_name);
5247 	if (wt_branch)
5248 		got_ref_close(wt_branch);
5249 	if (err) {
5250 		if (*branch_ref) {
5251 			got_ref_close(*branch_ref);
5252 			*branch_ref = NULL;
5253 		}
5254 		if (*tmp_branch) {
5255 			got_ref_close(*tmp_branch);
5256 			*tmp_branch = NULL;
5257 		}
5258 		free(*base_commit_id);
5259 		if (*fileindex) {
5260 			got_fileindex_free(*fileindex);
5261 			*fileindex = NULL;
5262 		}
5263 		lock_worktree(worktree, LOCK_SH);
5264 	}
5265 	return err;
5266 }
5267 
5268 const struct got_error *
5269 got_worktree_histedit_postpone(struct got_worktree *worktree,
5270     struct got_fileindex *fileindex)
5271 {
5272 	if (fileindex)
5273 		got_fileindex_free(fileindex);
5274 	return lock_worktree(worktree, LOCK_SH);
5275 }
5276 
5277 const struct got_error *
5278 got_worktree_histedit_in_progress(int *in_progress,
5279     struct got_worktree *worktree)
5280 {
5281 	const struct got_error *err;
5282 	char *tmp_branch_name = NULL;
5283 
5284 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
5285 	if (err)
5286 		return err;
5287 
5288 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
5289 	free(tmp_branch_name);
5290 	return NULL;
5291 }
5292 
5293 const struct got_error *
5294 got_worktree_histedit_continue(struct got_object_id **commit_id,
5295     struct got_reference **tmp_branch, struct got_reference **branch_ref,
5296     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
5297     struct got_worktree *worktree, struct got_repository *repo)
5298 {
5299 	const struct got_error *err;
5300 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
5301 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
5302 	struct got_reference *commit_ref = NULL;
5303 	struct got_reference *base_commit_ref = NULL;
5304 	char *fileindex_path = NULL;
5305 	int have_staged_files = 0;
5306 
5307 	*commit_id = NULL;
5308 	*tmp_branch = NULL;
5309 	*base_commit_id = NULL;
5310 	*fileindex = NULL;
5311 
5312 	err = lock_worktree(worktree, LOCK_EX);
5313 	if (err)
5314 		return err;
5315 
5316 	err = open_fileindex(fileindex, &fileindex_path, worktree);
5317 	if (err)
5318 		goto done;
5319 
5320 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
5321 	    &have_staged_files);
5322 	if (err && err->code != GOT_ERR_CANCELLED)
5323 		goto done;
5324 	if (have_staged_files) {
5325 		err = got_error(GOT_ERR_STAGED_PATHS);
5326 		goto done;
5327 	}
5328 
5329 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
5330 	if (err)
5331 		goto done;
5332 
5333 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
5334 	if (err)
5335 		goto done;
5336 
5337 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
5338 	if (err)
5339 		goto done;
5340 
5341 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
5342 	    worktree);
5343 	if (err)
5344 		goto done;
5345 
5346 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
5347 	if (err)
5348 		goto done;
5349 
5350 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
5351 	if (err)
5352 		goto done;
5353 	err = got_ref_resolve(commit_id, repo, commit_ref);
5354 	if (err)
5355 		goto done;
5356 
5357 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
5358 	if (err)
5359 		goto done;
5360 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
5361 	if (err)
5362 		goto done;
5363 
5364 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
5365 	if (err)
5366 		goto done;
5367 done:
5368 	free(commit_ref_name);
5369 	free(branch_ref_name);
5370 	free(fileindex_path);
5371 	if (commit_ref)
5372 		got_ref_close(commit_ref);
5373 	if (base_commit_ref)
5374 		got_ref_close(base_commit_ref);
5375 	if (err) {
5376 		free(*commit_id);
5377 		*commit_id = NULL;
5378 		free(*base_commit_id);
5379 		*base_commit_id = NULL;
5380 		if (*tmp_branch) {
5381 			got_ref_close(*tmp_branch);
5382 			*tmp_branch = NULL;
5383 		}
5384 		if (*fileindex) {
5385 			got_fileindex_free(*fileindex);
5386 			*fileindex = NULL;
5387 		}
5388 		lock_worktree(worktree, LOCK_EX);
5389 	}
5390 	return err;
5391 }
5392 
5393 static const struct got_error *
5394 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
5395 {
5396 	const struct got_error *err;
5397 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
5398 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
5399 
5400 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
5401 	if (err)
5402 		goto done;
5403 	err = delete_ref(tmp_branch_name, repo);
5404 	if (err)
5405 		goto done;
5406 
5407 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
5408 	    worktree);
5409 	if (err)
5410 		goto done;
5411 	err = delete_ref(base_commit_ref_name, repo);
5412 	if (err)
5413 		goto done;
5414 
5415 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
5416 	if (err)
5417 		goto done;
5418 	err = delete_ref(branch_ref_name, repo);
5419 	if (err)
5420 		goto done;
5421 
5422 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
5423 	if (err)
5424 		goto done;
5425 	err = delete_ref(commit_ref_name, repo);
5426 	if (err)
5427 		goto done;
5428 done:
5429 	free(tmp_branch_name);
5430 	free(base_commit_ref_name);
5431 	free(branch_ref_name);
5432 	free(commit_ref_name);
5433 	return err;
5434 }
5435 
5436 const struct got_error *
5437 got_worktree_histedit_abort(struct got_worktree *worktree,
5438     struct got_fileindex *fileindex, struct got_repository *repo,
5439     struct got_reference *branch, struct got_object_id *base_commit_id,
5440     got_worktree_checkout_cb progress_cb, void *progress_arg)
5441 {
5442 	const struct got_error *err, *unlockerr, *sync_err;
5443 	struct got_reference *resolved = NULL;
5444 	char *fileindex_path = NULL;
5445 	struct got_object_id *tree_id = NULL;
5446 	struct revert_file_args rfa;
5447 
5448 	err = lock_worktree(worktree, LOCK_EX);
5449 	if (err)
5450 		return err;
5451 
5452 	err = got_ref_open(&resolved, repo,
5453 	    got_ref_get_symref_target(branch), 0);
5454 	if (err)
5455 		goto done;
5456 
5457 	err = got_worktree_set_head_ref(worktree, resolved);
5458 	if (err)
5459 		goto done;
5460 
5461 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
5462 	if (err)
5463 		goto done;
5464 
5465 	err = got_object_id_by_path(&tree_id, repo, base_commit_id,
5466 	    worktree->path_prefix);
5467 	if (err)
5468 		goto done;
5469 
5470 	err = delete_histedit_refs(worktree, repo);
5471 	if (err)
5472 		goto done;
5473 
5474 	err = get_fileindex_path(&fileindex_path, worktree);
5475 	if (err)
5476 		goto done;
5477 
5478 	rfa.worktree = worktree;
5479 	rfa.fileindex = fileindex;
5480 	rfa.progress_cb = progress_cb;
5481 	rfa.progress_arg = progress_arg;
5482 	rfa.patch_cb = NULL;
5483 	rfa.patch_arg = NULL;
5484 	rfa.repo = repo;
5485 	err = worktree_status(worktree, "", fileindex, repo,
5486 	    revert_file, &rfa, NULL, NULL);
5487 	if (err)
5488 		goto sync;
5489 
5490 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
5491 	    repo, progress_cb, progress_arg, NULL, NULL);
5492 sync:
5493 	sync_err = sync_fileindex(fileindex, fileindex_path);
5494 	if (sync_err && err == NULL)
5495 		err = sync_err;
5496 done:
5497 	got_ref_close(resolved);
5498 	free(tree_id);
5499 	free(fileindex_path);
5500 
5501 	unlockerr = lock_worktree(worktree, LOCK_SH);
5502 	if (unlockerr && err == NULL)
5503 		err = unlockerr;
5504 	return err;
5505 }
5506 
5507 const struct got_error *
5508 got_worktree_histedit_complete(struct got_worktree *worktree,
5509     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
5510     struct got_reference *edited_branch, struct got_repository *repo)
5511 {
5512 	const struct got_error *err, *unlockerr;
5513 	struct got_object_id *new_head_commit_id = NULL;
5514 	struct got_reference *resolved = NULL;
5515 
5516 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
5517 	if (err)
5518 		return err;
5519 
5520 	err = got_ref_open(&resolved, repo,
5521 	    got_ref_get_symref_target(edited_branch), 0);
5522 	if (err)
5523 		goto done;
5524 
5525 	err = got_ref_change_ref(resolved, new_head_commit_id);
5526 	if (err)
5527 		goto done;
5528 
5529 	err = got_ref_write(resolved, repo);
5530 	if (err)
5531 		goto done;
5532 
5533 	err = got_worktree_set_head_ref(worktree, resolved);
5534 	if (err)
5535 		goto done;
5536 
5537 	err = delete_histedit_refs(worktree, repo);
5538 done:
5539 	if (fileindex)
5540 		got_fileindex_free(fileindex);
5541 	free(new_head_commit_id);
5542 	unlockerr = lock_worktree(worktree, LOCK_SH);
5543 	if (unlockerr && err == NULL)
5544 		err = unlockerr;
5545 	return err;
5546 }
5547 
5548 const struct got_error *
5549 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
5550     struct got_object_id *commit_id, struct got_repository *repo)
5551 {
5552 	const struct got_error *err;
5553 	char *commit_ref_name;
5554 
5555 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
5556 	if (err)
5557 		return err;
5558 
5559 	err = store_commit_id(commit_ref_name, commit_id, repo);
5560 	if (err)
5561 		goto done;
5562 
5563 	err = delete_ref(commit_ref_name, repo);
5564 done:
5565 	free(commit_ref_name);
5566 	return err;
5567 }
5568 
5569 struct check_stage_ok_arg {
5570 	struct got_object_id *head_commit_id;
5571 	struct got_worktree *worktree;
5572 	struct got_fileindex *fileindex;
5573 	struct got_repository *repo;
5574 	int have_changes;
5575 };
5576 
5577 const struct got_error *
5578 check_stage_ok(void *arg, unsigned char status,
5579     unsigned char staged_status, const char *relpath,
5580     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5581     struct got_object_id *commit_id)
5582 {
5583 	struct check_stage_ok_arg *a = arg;
5584 	const struct got_error *err = NULL;
5585 	struct got_fileindex_entry *ie;
5586 	struct got_object_id base_commit_id;
5587 	struct got_object_id *base_commit_idp = NULL;
5588 	char *in_repo_path = NULL, *p;
5589 
5590 	if (status == GOT_STATUS_UNVERSIONED)
5591 		return NULL;
5592 	if (status == GOT_STATUS_NONEXISTENT)
5593 		return got_error_set_errno(ENOENT, relpath);
5594 
5595 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
5596 	if (ie == NULL)
5597 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
5598 
5599 	if (asprintf(&in_repo_path, "%s%s%s", a->worktree->path_prefix,
5600 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
5601 	    relpath) == -1)
5602 		return got_error_from_errno("asprintf");
5603 
5604 	if (got_fileindex_entry_has_commit(ie)) {
5605 		memcpy(base_commit_id.sha1, ie->commit_sha1,
5606 		    SHA1_DIGEST_LENGTH);
5607 		base_commit_idp = &base_commit_id;
5608 	}
5609 
5610 	if (status == GOT_STATUS_NO_CHANGE) {
5611 		err = got_error_path(ie->path, GOT_ERR_STAGE_NO_CHANGE);
5612 		goto done;
5613 	} else if (status == GOT_STATUS_CONFLICT) {
5614 		err = got_error_path(ie->path, GOT_ERR_STAGE_CONFLICT);
5615 		goto done;
5616 	} else if (status != GOT_STATUS_ADD &&
5617 	    status != GOT_STATUS_MODIFY &&
5618 	    status != GOT_STATUS_DELETE) {
5619 		err = got_error_path(ie->path, GOT_ERR_FILE_STATUS);
5620 		goto done;
5621 	}
5622 
5623 	a->have_changes = 1;
5624 
5625 	p = in_repo_path;
5626 	while (p[0] == '/')
5627 		p++;
5628 	err = check_out_of_date(p, status, staged_status,
5629 	    blob_id, base_commit_idp, a->head_commit_id, a->repo,
5630 	    GOT_ERR_STAGE_OUT_OF_DATE);
5631 done:
5632 	free(in_repo_path);
5633 	return err;
5634 }
5635 
5636 struct stage_path_arg {
5637 	struct got_worktree *worktree;
5638 	struct got_fileindex *fileindex;
5639 	struct got_repository *repo;
5640 	got_worktree_status_cb status_cb;
5641 	void *status_arg;
5642 	got_worktree_patch_cb patch_cb;
5643 	void *patch_arg;
5644 };
5645 
5646 static const struct got_error *
5647 stage_path(void *arg, unsigned char status,
5648     unsigned char staged_status, const char *relpath,
5649     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5650     struct got_object_id *commit_id)
5651 {
5652 	struct stage_path_arg *a = arg;
5653 	const struct got_error *err = NULL;
5654 	struct got_fileindex_entry *ie;
5655 	char *ondisk_path = NULL, *path_content = NULL;
5656 	uint32_t stage;
5657 	struct got_object_id *new_staged_blob_id = NULL;
5658 
5659 	if (status == GOT_STATUS_UNVERSIONED)
5660 		return NULL;
5661 
5662 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
5663 	if (ie == NULL)
5664 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
5665 
5666 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
5667 	    relpath)== -1)
5668 		return got_error_from_errno("asprintf");
5669 
5670 	switch (status) {
5671 	case GOT_STATUS_ADD:
5672 	case GOT_STATUS_MODIFY:
5673 		if (a->patch_cb) {
5674 			if (status == GOT_STATUS_ADD) {
5675 				int choice = GOT_PATCH_CHOICE_NONE;
5676 				err = (*a->patch_cb)(&choice, a->patch_arg,
5677 				    status, ie->path, NULL, 1, 1);
5678 				if (err)
5679 					break;
5680 				if (choice != GOT_PATCH_CHOICE_YES)
5681 					break;
5682 			} else {
5683 				err = create_patched_content(&path_content, 0,
5684 				    staged_blob_id ? staged_blob_id : blob_id,
5685 				    ondisk_path, ie->path, a->repo,
5686 				    a->patch_cb, a->patch_arg);
5687 				if (err || path_content == NULL)
5688 					break;
5689 			}
5690 		}
5691 		err = got_object_blob_create(&new_staged_blob_id,
5692 		    path_content ? path_content : ondisk_path, a->repo);
5693 		if (err)
5694 			break;
5695 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
5696 		    SHA1_DIGEST_LENGTH);
5697 		if (status == GOT_STATUS_ADD || staged_status == GOT_STATUS_ADD)
5698 			stage = GOT_FILEIDX_STAGE_ADD;
5699 		else
5700 			stage = GOT_FILEIDX_STAGE_MODIFY;
5701 		got_fileindex_entry_stage_set(ie, stage);
5702 		if (a->status_cb == NULL)
5703 			break;
5704 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
5705 		    get_staged_status(ie), relpath, blob_id,
5706 		    new_staged_blob_id, NULL);
5707 		break;
5708 	case GOT_STATUS_DELETE:
5709 		if (staged_status == GOT_STATUS_DELETE)
5710 			break;
5711 		if (a->patch_cb) {
5712 			int choice = GOT_PATCH_CHOICE_NONE;
5713 			err = (*a->patch_cb)(&choice, a->patch_arg, status,
5714 			    ie->path, NULL, 1, 1);
5715 			if (err)
5716 				break;
5717 			if (choice == GOT_PATCH_CHOICE_NO)
5718 				break;
5719 			if (choice != GOT_PATCH_CHOICE_YES) {
5720 				err = got_error(GOT_ERR_PATCH_CHOICE);
5721 				break;
5722 			}
5723 		}
5724 		stage = GOT_FILEIDX_STAGE_DELETE;
5725 		got_fileindex_entry_stage_set(ie, stage);
5726 		if (a->status_cb == NULL)
5727 			break;
5728 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
5729 		    get_staged_status(ie), relpath, NULL, NULL, NULL);
5730 		break;
5731 	case GOT_STATUS_NO_CHANGE:
5732 		err = got_error_path(relpath, GOT_ERR_STAGE_NO_CHANGE);
5733 		break;
5734 	case GOT_STATUS_CONFLICT:
5735 		err = got_error_path(relpath, GOT_ERR_STAGE_CONFLICT);
5736 		break;
5737 	case GOT_STATUS_NONEXISTENT:
5738 		err = got_error_set_errno(ENOENT, relpath);
5739 		break;
5740 	default:
5741 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
5742 		break;
5743 	}
5744 
5745 	if (path_content && unlink(path_content) == -1 && err == NULL)
5746 		err = got_error_from_errno2("unlink", path_content);
5747 	free(path_content);
5748 	free(ondisk_path);
5749 	free(new_staged_blob_id);
5750 	return err;
5751 }
5752 
5753 const struct got_error *
5754 got_worktree_stage(struct got_worktree *worktree,
5755     struct got_pathlist_head *paths,
5756     got_worktree_status_cb status_cb, void *status_arg,
5757     got_worktree_patch_cb patch_cb, void *patch_arg,
5758     struct got_repository *repo)
5759 {
5760 	const struct got_error *err = NULL, *sync_err, *unlockerr;
5761 	struct got_pathlist_entry *pe;
5762 	struct got_fileindex *fileindex = NULL;
5763 	char *fileindex_path = NULL;
5764 	struct got_reference *head_ref = NULL;
5765 	struct got_object_id *head_commit_id = NULL;
5766 	struct check_stage_ok_arg oka;
5767 	struct stage_path_arg spa;
5768 
5769 	err = lock_worktree(worktree, LOCK_EX);
5770 	if (err)
5771 		return err;
5772 
5773 	err = got_ref_open(&head_ref, repo,
5774 	    got_worktree_get_head_ref_name(worktree), 0);
5775 	if (err)
5776 		goto done;
5777 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
5778 	if (err)
5779 		goto done;
5780 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
5781 	if (err)
5782 		goto done;
5783 
5784 	/* Check pre-conditions before staging anything. */
5785 	oka.head_commit_id = head_commit_id;
5786 	oka.worktree = worktree;
5787 	oka.fileindex = fileindex;
5788 	oka.repo = repo;
5789 	oka.have_changes = 0;
5790 	TAILQ_FOREACH(pe, paths, entry) {
5791 		err = worktree_status(worktree, pe->path, fileindex, repo,
5792 		    check_stage_ok, &oka, NULL, NULL);
5793 		if (err)
5794 			goto done;
5795 	}
5796 	if (!oka.have_changes) {
5797 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
5798 		goto done;
5799 	}
5800 
5801 	spa.worktree = worktree;
5802 	spa.fileindex = fileindex;
5803 	spa.repo = repo;
5804 	spa.patch_cb = patch_cb;
5805 	spa.patch_arg = patch_arg;
5806 	spa.status_cb = status_cb;
5807 	spa.status_arg = status_arg;
5808 	TAILQ_FOREACH(pe, paths, entry) {
5809 		err = worktree_status(worktree, pe->path, fileindex, repo,
5810 		    stage_path, &spa, NULL, NULL);
5811 		if (err)
5812 			goto done;
5813 	}
5814 
5815 	sync_err = sync_fileindex(fileindex, fileindex_path);
5816 	if (sync_err && err == NULL)
5817 		err = sync_err;
5818 done:
5819 	if (head_ref)
5820 		got_ref_close(head_ref);
5821 	free(head_commit_id);
5822 	free(fileindex_path);
5823 	if (fileindex)
5824 		got_fileindex_free(fileindex);
5825 	unlockerr = lock_worktree(worktree, LOCK_SH);
5826 	if (unlockerr && err == NULL)
5827 		err = unlockerr;
5828 	return err;
5829 }
5830 
5831 struct unstage_path_arg {
5832 	struct got_worktree *worktree;
5833 	struct got_fileindex *fileindex;
5834 	struct got_repository *repo;
5835 	got_worktree_checkout_cb progress_cb;
5836 	void *progress_arg;
5837 	got_worktree_patch_cb patch_cb;
5838 	void *patch_arg;
5839 };
5840 
5841 static const struct got_error *
5842 create_unstaged_content(char **path_unstaged_content,
5843     char **path_new_staged_content, struct got_object_id *blob_id,
5844     struct got_object_id *staged_blob_id, const char *relpath,
5845     struct got_repository *repo,
5846     got_worktree_patch_cb patch_cb, void *patch_arg)
5847 {
5848 	const struct got_error *err;
5849 	struct got_blob_object *blob = NULL, *staged_blob = NULL;
5850 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL, *rejectfile = NULL;
5851 	char *path1 = NULL, *path2 = NULL, *label1 = NULL;
5852 	struct stat sb1, sb2;
5853 	struct got_diff_changes *changes = NULL;
5854 	struct got_diff_state *ds = NULL;
5855 	struct got_diff_args *args = NULL;
5856 	struct got_diff_change *change;
5857 	int diff_flags = 0, line_cur1 = 1, line_cur2 = 1, n = 0;
5858 	int have_content = 0, have_rejected_content = 0;
5859 
5860 	*path_unstaged_content = NULL;
5861 	*path_new_staged_content = NULL;
5862 
5863 	err = got_object_id_str(&label1, blob_id);
5864 	if (err)
5865 		return err;
5866 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192);
5867 	if (err)
5868 		goto done;
5869 
5870 	err = got_opentemp_named(&path1, &f1, "got-unstage-blob-base");
5871 	if (err)
5872 		goto done;
5873 
5874 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
5875 	if (err)
5876 		goto done;
5877 
5878 	err = got_object_open_as_blob(&staged_blob, repo, staged_blob_id, 8192);
5879 	if (err)
5880 		goto done;
5881 
5882 	err = got_opentemp_named(&path2, &f2, "got-unstage-blob-staged");
5883 	if (err)
5884 		goto done;
5885 
5886 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f2, staged_blob);
5887 	if (err)
5888 		goto done;
5889 
5890 	if (stat(path1, &sb1) == -1) {
5891 		err = got_error_from_errno2("stat", path1);
5892 		goto done;
5893 	}
5894 
5895 	if (stat(path2, &sb2) == -1) {
5896 		err = got_error_from_errno2("stat", path2);
5897 		goto done;
5898 	}
5899 
5900 	err = got_diff_files(&changes, &ds, &args, &diff_flags,
5901 	    f1, sb1.st_size, label1, f2, sb2.st_size, path2, 3, NULL);
5902 	if (err)
5903 		goto done;
5904 
5905 	err = got_opentemp_named(path_unstaged_content, &outfile,
5906 	    "got-unstaged-content");
5907 	if (err)
5908 		goto done;
5909 	err = got_opentemp_named(path_new_staged_content, &rejectfile,
5910 	    "got-new-staged-content");
5911 	if (err)
5912 		goto done;
5913 
5914 	if (fseek(f1, 0L, SEEK_SET) == -1) {
5915 		err = got_ferror(f1, GOT_ERR_IO);
5916 		goto done;
5917 	}
5918 	if (fseek(f2, 0L, SEEK_SET) == -1) {
5919 		err = got_ferror(f2, GOT_ERR_IO);
5920 		goto done;
5921 	}
5922 	SIMPLEQ_FOREACH(change, &changes->entries, entry) {
5923 		int choice;
5924 		err = apply_or_reject_change(&choice, change, ++n,
5925 		    changes->nchanges, ds, args, diff_flags, relpath,
5926 		    f1, f2, &line_cur1, &line_cur2,
5927 		    outfile, rejectfile, patch_cb, patch_arg);
5928 		if (err)
5929 			goto done;
5930 		if (choice == GOT_PATCH_CHOICE_YES)
5931 			have_content = 1;
5932 		else
5933 			have_rejected_content = 1;
5934 		if (choice == GOT_PATCH_CHOICE_QUIT)
5935 			break;
5936 	}
5937 	if (have_content || have_rejected_content)
5938 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
5939 		    outfile, rejectfile);
5940 done:
5941 	free(label1);
5942 	if (blob)
5943 		got_object_blob_close(blob);
5944 	if (staged_blob)
5945 		got_object_blob_close(staged_blob);
5946 	if (f1 && fclose(f1) == EOF && err == NULL)
5947 		err = got_error_from_errno2("fclose", path1);
5948 	if (f2 && fclose(f2) == EOF && err == NULL)
5949 		err = got_error_from_errno2("fclose", path2);
5950 	if (outfile && fclose(outfile) == EOF && err == NULL)
5951 		err = got_error_from_errno2("fclose", *path_unstaged_content);
5952 	if (rejectfile && fclose(rejectfile) == EOF && err == NULL)
5953 		err = got_error_from_errno2("fclose", *path_new_staged_content);
5954 	if (path1 && unlink(path1) == -1 && err == NULL)
5955 		err = got_error_from_errno2("unlink", path1);
5956 	if (path2 && unlink(path2) == -1 && err == NULL)
5957 		err = got_error_from_errno2("unlink", path2);
5958 	if (err || !have_content) {
5959 		if (*path_unstaged_content &&
5960 		    unlink(*path_unstaged_content) == -1 && err == NULL)
5961 			err = got_error_from_errno2("unlink",
5962 			    *path_unstaged_content);
5963 		free(*path_unstaged_content);
5964 		*path_unstaged_content = NULL;
5965 	}
5966 	if (err || !have_rejected_content) {
5967 		if (*path_new_staged_content &&
5968 		    unlink(*path_new_staged_content) == -1 && err == NULL)
5969 			err = got_error_from_errno2("unlink",
5970 			    *path_new_staged_content);
5971 		free(*path_new_staged_content);
5972 		*path_new_staged_content = NULL;
5973 	}
5974 	free(args);
5975 	if (ds) {
5976 		got_diff_state_free(ds);
5977 		free(ds);
5978 	}
5979 	if (changes)
5980 		got_diff_free_changes(changes);
5981 	free(path1);
5982 	free(path2);
5983 	return err;
5984 }
5985 
5986 static const struct got_error *
5987 unstage_path(void *arg, unsigned char status,
5988     unsigned char staged_status, const char *relpath,
5989     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5990     struct got_object_id *commit_id)
5991 {
5992 	const struct got_error *err = NULL;
5993 	struct unstage_path_arg *a = arg;
5994 	struct got_fileindex_entry *ie;
5995 	struct got_blob_object *blob_base = NULL, *blob_staged = NULL;
5996 	char *ondisk_path = NULL, *path_unstaged_content = NULL;
5997 	char *path_new_staged_content = NULL;
5998 	int local_changes_subsumed;
5999 	struct stat sb;
6000 
6001 	if (staged_status != GOT_STATUS_ADD &&
6002 	    staged_status != GOT_STATUS_MODIFY &&
6003 	    staged_status != GOT_STATUS_DELETE)
6004 		return NULL;
6005 
6006 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
6007 	if (ie == NULL)
6008 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
6009 
6010 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, relpath)
6011 	    == -1)
6012 		return got_error_from_errno("asprintf");
6013 
6014 	switch (staged_status) {
6015 	case GOT_STATUS_MODIFY:
6016 		err = got_object_open_as_blob(&blob_base, a->repo,
6017 		    blob_id, 8192);
6018 		if (err)
6019 			break;
6020 		/* fall through */
6021 	case GOT_STATUS_ADD:
6022 		if (a->patch_cb) {
6023 			if (staged_status == GOT_STATUS_ADD) {
6024 				int choice = GOT_PATCH_CHOICE_NONE;
6025 				err = (*a->patch_cb)(&choice, a->patch_arg,
6026 				    staged_status, ie->path, NULL, 1, 1);
6027 				if (err)
6028 					break;
6029 				if (choice != GOT_PATCH_CHOICE_YES)
6030 					break;
6031 			} else {
6032 				err = create_unstaged_content(
6033 				    &path_unstaged_content,
6034 				    &path_new_staged_content, blob_id,
6035 				    staged_blob_id, ie->path, a->repo,
6036 				    a->patch_cb, a->patch_arg);
6037 				if (err || path_unstaged_content == NULL)
6038 					break;
6039 				if (path_new_staged_content) {
6040 					err = got_object_blob_create(
6041 					    &staged_blob_id,
6042 					    path_new_staged_content,
6043 					    a->repo);
6044 					if (err)
6045 						break;
6046 					memcpy(ie->staged_blob_sha1,
6047 					    staged_blob_id->sha1,
6048 					    SHA1_DIGEST_LENGTH);
6049 				}
6050 				err = merge_file(&local_changes_subsumed,
6051 				    a->worktree, blob_base, ondisk_path,
6052 				    relpath, got_fileindex_perms_to_st(ie),
6053 				    path_unstaged_content, "unstaged",
6054 				    a->repo, a->progress_cb, a->progress_arg);
6055 				if (err == NULL &&
6056 				    path_new_staged_content == NULL)
6057 					got_fileindex_entry_stage_set(ie,
6058 					    GOT_FILEIDX_STAGE_NONE);
6059 				break; /* Done with this file. */
6060 			}
6061 		}
6062 		err = got_object_open_as_blob(&blob_staged, a->repo,
6063 		    staged_blob_id, 8192);
6064 		if (err)
6065 			break;
6066 		err = merge_blob(&local_changes_subsumed, a->worktree,
6067 		    blob_base, ondisk_path, relpath,
6068 		    got_fileindex_perms_to_st(ie), blob_staged,
6069 		    commit_id ? commit_id : a->worktree->base_commit_id,
6070 		    a->repo, a->progress_cb, a->progress_arg);
6071 		if (err == NULL)
6072 			got_fileindex_entry_stage_set(ie,
6073 			    GOT_FILEIDX_STAGE_NONE);
6074 		break;
6075 	case GOT_STATUS_DELETE:
6076 		if (a->patch_cb) {
6077 			int choice = GOT_PATCH_CHOICE_NONE;
6078 			err = (*a->patch_cb)(&choice, a->patch_arg,
6079 			    staged_status, ie->path, NULL, 1, 1);
6080 			if (err)
6081 				break;
6082 			if (choice == GOT_PATCH_CHOICE_NO)
6083 				break;
6084 			if (choice != GOT_PATCH_CHOICE_YES) {
6085 				err = got_error(GOT_ERR_PATCH_CHOICE);
6086 				break;
6087 			}
6088 		}
6089 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
6090 		err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
6091 		if (err)
6092 			break;
6093 		err = (*a->progress_cb)(a->progress_arg, status, relpath);
6094 		break;
6095 	}
6096 
6097 	free(ondisk_path);
6098 	if (path_unstaged_content &&
6099 	    unlink(path_unstaged_content) == -1 && err == NULL)
6100 		err = got_error_from_errno2("unlink", path_unstaged_content);
6101 	if (path_new_staged_content &&
6102 	    unlink(path_new_staged_content) == -1 && err == NULL)
6103 		err = got_error_from_errno2("unlink", path_new_staged_content);
6104 	free(path_unstaged_content);
6105 	free(path_new_staged_content);
6106 	if (blob_base)
6107 		got_object_blob_close(blob_base);
6108 	if (blob_staged)
6109 		got_object_blob_close(blob_staged);
6110 	return err;
6111 }
6112 
6113 const struct got_error *
6114 got_worktree_unstage(struct got_worktree *worktree,
6115     struct got_pathlist_head *paths,
6116     got_worktree_checkout_cb progress_cb, void *progress_arg,
6117     got_worktree_patch_cb patch_cb, void *patch_arg,
6118     struct got_repository *repo)
6119 {
6120 	const struct got_error *err = NULL, *sync_err, *unlockerr;
6121 	struct got_pathlist_entry *pe;
6122 	struct got_fileindex *fileindex = NULL;
6123 	char *fileindex_path = NULL;
6124 	struct unstage_path_arg upa;
6125 
6126 	err = lock_worktree(worktree, LOCK_EX);
6127 	if (err)
6128 		return err;
6129 
6130 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
6131 	if (err)
6132 		goto done;
6133 
6134 	upa.worktree = worktree;
6135 	upa.fileindex = fileindex;
6136 	upa.repo = repo;
6137 	upa.progress_cb = progress_cb;
6138 	upa.progress_arg = progress_arg;
6139 	upa.patch_cb = patch_cb;
6140 	upa.patch_arg = patch_arg;
6141 	TAILQ_FOREACH(pe, paths, entry) {
6142 		err = worktree_status(worktree, pe->path, fileindex, repo,
6143 		    unstage_path, &upa, NULL, NULL);
6144 		if (err)
6145 			goto done;
6146 	}
6147 
6148 	sync_err = sync_fileindex(fileindex, fileindex_path);
6149 	if (sync_err && err == NULL)
6150 		err = sync_err;
6151 done:
6152 	free(fileindex_path);
6153 	if (fileindex)
6154 		got_fileindex_free(fileindex);
6155 	unlockerr = lock_worktree(worktree, LOCK_SH);
6156 	if (unlockerr && err == NULL)
6157 		err = unlockerr;
6158 	return err;
6159 }