commit: add repository argument to lookup_commit_reference_gently
[git/git.git] / builtin / checkout.c
1 #include "builtin.h"
2 #include "config.h"
3 #include "checkout.h"
4 #include "lockfile.h"
5 #include "parse-options.h"
6 #include "refs.h"
7 #include "object-store.h"
8 #include "commit.h"
9 #include "tree.h"
10 #include "tree-walk.h"
11 #include "cache-tree.h"
12 #include "unpack-trees.h"
13 #include "dir.h"
14 #include "run-command.h"
15 #include "merge-recursive.h"
16 #include "branch.h"
17 #include "diff.h"
18 #include "revision.h"
19 #include "remote.h"
20 #include "blob.h"
21 #include "xdiff-interface.h"
22 #include "ll-merge.h"
23 #include "resolve-undo.h"
24 #include "submodule-config.h"
25 #include "submodule.h"
26
27 static const char * const checkout_usage[] = {
28 N_("git checkout [<options>] <branch>"),
29 N_("git checkout [<options>] [<branch>] -- <file>..."),
30 NULL,
31 };
32
33 struct checkout_opts {
34 int patch_mode;
35 int quiet;
36 int merge;
37 int force;
38 int force_detach;
39 int writeout_stage;
40 int overwrite_ignore;
41 int ignore_skipworktree;
42 int ignore_other_worktrees;
43 int show_progress;
44
45 const char *new_branch;
46 const char *new_branch_force;
47 const char *new_orphan_branch;
48 int new_branch_log;
49 enum branch_track track;
50 struct diff_options diff_options;
51
52 int branch_exists;
53 const char *prefix;
54 struct pathspec pathspec;
55 struct tree *source_tree;
56 };
57
58 static int post_checkout_hook(struct commit *old_commit, struct commit *new_commit,
59 int changed)
60 {
61 return run_hook_le(NULL, "post-checkout",
62 oid_to_hex(old_commit ? &old_commit->object.oid : &null_oid),
63 oid_to_hex(new_commit ? &new_commit->object.oid : &null_oid),
64 changed ? "1" : "0", NULL);
65 /* "new_commit" can be NULL when checking out from the index before
66 a commit exists. */
67
68 }
69
70 static int update_some(const struct object_id *oid, struct strbuf *base,
71 const char *pathname, unsigned mode, int stage, void *context)
72 {
73 int len;
74 struct cache_entry *ce;
75 int pos;
76
77 if (S_ISDIR(mode))
78 return READ_TREE_RECURSIVE;
79
80 len = base->len + strlen(pathname);
81 ce = xcalloc(1, cache_entry_size(len));
82 oidcpy(&ce->oid, oid);
83 memcpy(ce->name, base->buf, base->len);
84 memcpy(ce->name + base->len, pathname, len - base->len);
85 ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
86 ce->ce_namelen = len;
87 ce->ce_mode = create_ce_mode(mode);
88
89 /*
90 * If the entry is the same as the current index, we can leave the old
91 * entry in place. Whether it is UPTODATE or not, checkout_entry will
92 * do the right thing.
93 */
94 pos = cache_name_pos(ce->name, ce->ce_namelen);
95 if (pos >= 0) {
96 struct cache_entry *old = active_cache[pos];
97 if (ce->ce_mode == old->ce_mode &&
98 !oidcmp(&ce->oid, &old->oid)) {
99 old->ce_flags |= CE_UPDATE;
100 free(ce);
101 return 0;
102 }
103 }
104
105 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
106 return 0;
107 }
108
109 static int read_tree_some(struct tree *tree, const struct pathspec *pathspec)
110 {
111 read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
112
113 /* update the index with the given tree's info
114 * for all args, expanding wildcards, and exit
115 * with any non-zero return code.
116 */
117 return 0;
118 }
119
120 static int skip_same_name(const struct cache_entry *ce, int pos)
121 {
122 while (++pos < active_nr &&
123 !strcmp(active_cache[pos]->name, ce->name))
124 ; /* skip */
125 return pos;
126 }
127
128 static int check_stage(int stage, const struct cache_entry *ce, int pos)
129 {
130 while (pos < active_nr &&
131 !strcmp(active_cache[pos]->name, ce->name)) {
132 if (ce_stage(active_cache[pos]) == stage)
133 return 0;
134 pos++;
135 }
136 if (stage == 2)
137 return error(_("path '%s' does not have our version"), ce->name);
138 else
139 return error(_("path '%s' does not have their version"), ce->name);
140 }
141
142 static int check_stages(unsigned stages, const struct cache_entry *ce, int pos)
143 {
144 unsigned seen = 0;
145 const char *name = ce->name;
146
147 while (pos < active_nr) {
148 ce = active_cache[pos];
149 if (strcmp(name, ce->name))
150 break;
151 seen |= (1 << ce_stage(ce));
152 pos++;
153 }
154 if ((stages & seen) != stages)
155 return error(_("path '%s' does not have all necessary versions"),
156 name);
157 return 0;
158 }
159
160 static int checkout_stage(int stage, const struct cache_entry *ce, int pos,
161 const struct checkout *state)
162 {
163 while (pos < active_nr &&
164 !strcmp(active_cache[pos]->name, ce->name)) {
165 if (ce_stage(active_cache[pos]) == stage)
166 return checkout_entry(active_cache[pos], state, NULL);
167 pos++;
168 }
169 if (stage == 2)
170 return error(_("path '%s' does not have our version"), ce->name);
171 else
172 return error(_("path '%s' does not have their version"), ce->name);
173 }
174
175 static int checkout_merged(int pos, const struct checkout *state)
176 {
177 struct cache_entry *ce = active_cache[pos];
178 const char *path = ce->name;
179 mmfile_t ancestor, ours, theirs;
180 int status;
181 struct object_id oid;
182 mmbuffer_t result_buf;
183 struct object_id threeway[3];
184 unsigned mode = 0;
185
186 memset(threeway, 0, sizeof(threeway));
187 while (pos < active_nr) {
188 int stage;
189 stage = ce_stage(ce);
190 if (!stage || strcmp(path, ce->name))
191 break;
192 oidcpy(&threeway[stage - 1], &ce->oid);
193 if (stage == 2)
194 mode = create_ce_mode(ce->ce_mode);
195 pos++;
196 ce = active_cache[pos];
197 }
198 if (is_null_oid(&threeway[1]) || is_null_oid(&threeway[2]))
199 return error(_("path '%s' does not have necessary versions"), path);
200
201 read_mmblob(&ancestor, &threeway[0]);
202 read_mmblob(&ours, &threeway[1]);
203 read_mmblob(&theirs, &threeway[2]);
204
205 /*
206 * NEEDSWORK: re-create conflicts from merges with
207 * merge.renormalize set, too
208 */
209 status = ll_merge(&result_buf, path, &ancestor, "base",
210 &ours, "ours", &theirs, "theirs", NULL);
211 free(ancestor.ptr);
212 free(ours.ptr);
213 free(theirs.ptr);
214 if (status < 0 || !result_buf.ptr) {
215 free(result_buf.ptr);
216 return error(_("path '%s': cannot merge"), path);
217 }
218
219 /*
220 * NEEDSWORK:
221 * There is absolutely no reason to write this as a blob object
222 * and create a phony cache entry. This hack is primarily to get
223 * to the write_entry() machinery that massages the contents to
224 * work-tree format and writes out which only allows it for a
225 * cache entry. The code in write_entry() needs to be refactored
226 * to allow us to feed a <buffer, size, mode> instead of a cache
227 * entry. Such a refactoring would help merge_recursive as well
228 * (it also writes the merge result to the object database even
229 * when it may contain conflicts).
230 */
231 if (write_object_file(result_buf.ptr, result_buf.size, blob_type, &oid))
232 die(_("Unable to add merge result for '%s'"), path);
233 free(result_buf.ptr);
234 ce = make_cache_entry(mode, oid.hash, path, 2, 0);
235 if (!ce)
236 die(_("make_cache_entry failed for path '%s'"), path);
237 status = checkout_entry(ce, state, NULL);
238 free(ce);
239 return status;
240 }
241
242 static int checkout_paths(const struct checkout_opts *opts,
243 const char *revision)
244 {
245 int pos;
246 struct checkout state = CHECKOUT_INIT;
247 static char *ps_matched;
248 struct object_id rev;
249 struct commit *head;
250 int errs = 0;
251 struct lock_file lock_file = LOCK_INIT;
252
253 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
254 die(_("'%s' cannot be used with updating paths"), "--track");
255
256 if (opts->new_branch_log)
257 die(_("'%s' cannot be used with updating paths"), "-l");
258
259 if (opts->force && opts->patch_mode)
260 die(_("'%s' cannot be used with updating paths"), "-f");
261
262 if (opts->force_detach)
263 die(_("'%s' cannot be used with updating paths"), "--detach");
264
265 if (opts->merge && opts->patch_mode)
266 die(_("'%s' cannot be used with %s"), "--merge", "--patch");
267
268 if (opts->force && opts->merge)
269 die(_("'%s' cannot be used with %s"), "-f", "-m");
270
271 if (opts->new_branch)
272 die(_("Cannot update paths and switch to branch '%s' at the same time."),
273 opts->new_branch);
274
275 if (opts->patch_mode)
276 return run_add_interactive(revision, "--patch=checkout",
277 &opts->pathspec);
278
279 hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
280 if (read_cache_preload(&opts->pathspec) < 0)
281 return error(_("index file corrupt"));
282
283 if (opts->source_tree)
284 read_tree_some(opts->source_tree, &opts->pathspec);
285
286 ps_matched = xcalloc(opts->pathspec.nr, 1);
287
288 /*
289 * Make sure all pathspecs participated in locating the paths
290 * to be checked out.
291 */
292 for (pos = 0; pos < active_nr; pos++) {
293 struct cache_entry *ce = active_cache[pos];
294 ce->ce_flags &= ~CE_MATCHED;
295 if (!opts->ignore_skipworktree && ce_skip_worktree(ce))
296 continue;
297 if (opts->source_tree && !(ce->ce_flags & CE_UPDATE))
298 /*
299 * "git checkout tree-ish -- path", but this entry
300 * is in the original index; it will not be checked
301 * out to the working tree and it does not matter
302 * if pathspec matched this entry. We will not do
303 * anything to this entry at all.
304 */
305 continue;
306 /*
307 * Either this entry came from the tree-ish we are
308 * checking the paths out of, or we are checking out
309 * of the index.
310 *
311 * If it comes from the tree-ish, we already know it
312 * matches the pathspec and could just stamp
313 * CE_MATCHED to it from update_some(). But we still
314 * need ps_matched and read_tree_recursive (and
315 * eventually tree_entry_interesting) cannot fill
316 * ps_matched yet. Once it can, we can avoid calling
317 * match_pathspec() for _all_ entries when
318 * opts->source_tree != NULL.
319 */
320 if (ce_path_match(ce, &opts->pathspec, ps_matched))
321 ce->ce_flags |= CE_MATCHED;
322 }
323
324 if (report_path_error(ps_matched, &opts->pathspec, opts->prefix)) {
325 free(ps_matched);
326 return 1;
327 }
328 free(ps_matched);
329
330 /* "checkout -m path" to recreate conflicted state */
331 if (opts->merge)
332 unmerge_marked_index(&the_index);
333
334 /* Any unmerged paths? */
335 for (pos = 0; pos < active_nr; pos++) {
336 const struct cache_entry *ce = active_cache[pos];
337 if (ce->ce_flags & CE_MATCHED) {
338 if (!ce_stage(ce))
339 continue;
340 if (opts->force) {
341 warning(_("path '%s' is unmerged"), ce->name);
342 } else if (opts->writeout_stage) {
343 errs |= check_stage(opts->writeout_stage, ce, pos);
344 } else if (opts->merge) {
345 errs |= check_stages((1<<2) | (1<<3), ce, pos);
346 } else {
347 errs = 1;
348 error(_("path '%s' is unmerged"), ce->name);
349 }
350 pos = skip_same_name(ce, pos) - 1;
351 }
352 }
353 if (errs)
354 return 1;
355
356 /* Now we are committed to check them out */
357 state.force = 1;
358 state.refresh_cache = 1;
359 state.istate = &the_index;
360
361 enable_delayed_checkout(&state);
362 for (pos = 0; pos < active_nr; pos++) {
363 struct cache_entry *ce = active_cache[pos];
364 if (ce->ce_flags & CE_MATCHED) {
365 if (!ce_stage(ce)) {
366 errs |= checkout_entry(ce, &state, NULL);
367 continue;
368 }
369 if (opts->writeout_stage)
370 errs |= checkout_stage(opts->writeout_stage, ce, pos, &state);
371 else if (opts->merge)
372 errs |= checkout_merged(pos, &state);
373 pos = skip_same_name(ce, pos) - 1;
374 }
375 }
376 errs |= finish_delayed_checkout(&state);
377
378 if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
379 die(_("unable to write new index file"));
380
381 read_ref_full("HEAD", 0, &rev, NULL);
382 head = lookup_commit_reference_gently(the_repository, &rev, 1);
383
384 errs |= post_checkout_hook(head, head, 0);
385 return errs;
386 }
387
388 static void show_local_changes(struct object *head,
389 const struct diff_options *opts)
390 {
391 struct rev_info rev;
392 /* I think we want full paths, even if we're in a subdirectory. */
393 init_revisions(&rev, NULL);
394 rev.diffopt.flags = opts->flags;
395 rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
396 diff_setup_done(&rev.diffopt);
397 add_pending_object(&rev, head, NULL);
398 run_diff_index(&rev, 0);
399 }
400
401 static void describe_detached_head(const char *msg, struct commit *commit)
402 {
403 struct strbuf sb = STRBUF_INIT;
404
405 if (!parse_commit(commit))
406 pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
407 if (print_sha1_ellipsis()) {
408 fprintf(stderr, "%s %s... %s\n", msg,
409 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV), sb.buf);
410 } else {
411 fprintf(stderr, "%s %s %s\n", msg,
412 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV), sb.buf);
413 }
414 strbuf_release(&sb);
415 }
416
417 static int reset_tree(struct tree *tree, const struct checkout_opts *o,
418 int worktree, int *writeout_error)
419 {
420 struct unpack_trees_options opts;
421 struct tree_desc tree_desc;
422
423 memset(&opts, 0, sizeof(opts));
424 opts.head_idx = -1;
425 opts.update = worktree;
426 opts.skip_unmerged = !worktree;
427 opts.reset = 1;
428 opts.merge = 1;
429 opts.fn = oneway_merge;
430 opts.verbose_update = o->show_progress;
431 opts.src_index = &the_index;
432 opts.dst_index = &the_index;
433 parse_tree(tree);
434 init_tree_desc(&tree_desc, tree->buffer, tree->size);
435 switch (unpack_trees(1, &tree_desc, &opts)) {
436 case -2:
437 *writeout_error = 1;
438 /*
439 * We return 0 nevertheless, as the index is all right
440 * and more importantly we have made best efforts to
441 * update paths in the work tree, and we cannot revert
442 * them.
443 */
444 /* fallthrough */
445 case 0:
446 return 0;
447 default:
448 return 128;
449 }
450 }
451
452 struct branch_info {
453 const char *name; /* The short name used */
454 const char *path; /* The full name of a real branch */
455 struct commit *commit; /* The named commit */
456 /*
457 * if not null the branch is detached because it's already
458 * checked out in this checkout
459 */
460 char *checkout;
461 };
462
463 static void setup_branch_path(struct branch_info *branch)
464 {
465 struct strbuf buf = STRBUF_INIT;
466
467 strbuf_branchname(&buf, branch->name, INTERPRET_BRANCH_LOCAL);
468 if (strcmp(buf.buf, branch->name))
469 branch->name = xstrdup(buf.buf);
470 strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
471 branch->path = strbuf_detach(&buf, NULL);
472 }
473
474 static int merge_working_tree(const struct checkout_opts *opts,
475 struct branch_info *old_branch_info,
476 struct branch_info *new_branch_info,
477 int *writeout_error)
478 {
479 int ret;
480 struct lock_file lock_file = LOCK_INIT;
481
482 hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
483 if (read_cache_preload(NULL) < 0)
484 return error(_("index file corrupt"));
485
486 resolve_undo_clear();
487 if (opts->force) {
488 ret = reset_tree(get_commit_tree(new_branch_info->commit),
489 opts, 1, writeout_error);
490 if (ret)
491 return ret;
492 } else {
493 struct tree_desc trees[2];
494 struct tree *tree;
495 struct unpack_trees_options topts;
496
497 memset(&topts, 0, sizeof(topts));
498 topts.head_idx = -1;
499 topts.src_index = &the_index;
500 topts.dst_index = &the_index;
501
502 setup_unpack_trees_porcelain(&topts, "checkout");
503
504 refresh_cache(REFRESH_QUIET);
505
506 if (unmerged_cache()) {
507 error(_("you need to resolve your current index first"));
508 return 1;
509 }
510
511 /* 2-way merge to the new branch */
512 topts.initial_checkout = is_cache_unborn();
513 topts.update = 1;
514 topts.merge = 1;
515 topts.gently = opts->merge && old_branch_info->commit;
516 topts.verbose_update = opts->show_progress;
517 topts.fn = twoway_merge;
518 if (opts->overwrite_ignore) {
519 topts.dir = xcalloc(1, sizeof(*topts.dir));
520 topts.dir->flags |= DIR_SHOW_IGNORED;
521 setup_standard_excludes(topts.dir);
522 }
523 tree = parse_tree_indirect(old_branch_info->commit ?
524 &old_branch_info->commit->object.oid :
525 the_hash_algo->empty_tree);
526 init_tree_desc(&trees[0], tree->buffer, tree->size);
527 tree = parse_tree_indirect(&new_branch_info->commit->object.oid);
528 init_tree_desc(&trees[1], tree->buffer, tree->size);
529
530 ret = unpack_trees(2, trees, &topts);
531 clear_unpack_trees_porcelain(&topts);
532 if (ret == -1) {
533 /*
534 * Unpack couldn't do a trivial merge; either
535 * give up or do a real merge, depending on
536 * whether the merge flag was used.
537 */
538 struct tree *result;
539 struct tree *work;
540 struct merge_options o;
541 if (!opts->merge)
542 return 1;
543
544 /*
545 * Without old_branch_info->commit, the below is the same as
546 * the two-tree unpack we already tried and failed.
547 */
548 if (!old_branch_info->commit)
549 return 1;
550
551 /* Do more real merge */
552
553 /*
554 * We update the index fully, then write the
555 * tree from the index, then merge the new
556 * branch with the current tree, with the old
557 * branch as the base. Then we reset the index
558 * (but not the working tree) to the new
559 * branch, leaving the working tree as the
560 * merged version, but skipping unmerged
561 * entries in the index.
562 */
563
564 add_files_to_cache(NULL, NULL, 0);
565 /*
566 * NEEDSWORK: carrying over local changes
567 * when branches have different end-of-line
568 * normalization (or clean+smudge rules) is
569 * a pain; plumb in an option to set
570 * o.renormalize?
571 */
572 init_merge_options(&o);
573 o.verbosity = 0;
574 work = write_tree_from_memory(&o);
575
576 ret = reset_tree(get_commit_tree(new_branch_info->commit),
577 opts, 1,
578 writeout_error);
579 if (ret)
580 return ret;
581 o.ancestor = old_branch_info->name;
582 o.branch1 = new_branch_info->name;
583 o.branch2 = "local";
584 ret = merge_trees(&o,
585 get_commit_tree(new_branch_info->commit),
586 work,
587 get_commit_tree(old_branch_info->commit),
588 &result);
589 if (ret < 0)
590 exit(128);
591 ret = reset_tree(get_commit_tree(new_branch_info->commit),
592 opts, 0,
593 writeout_error);
594 strbuf_release(&o.obuf);
595 if (ret)
596 return ret;
597 }
598 }
599
600 if (!active_cache_tree)
601 active_cache_tree = cache_tree();
602
603 if (!cache_tree_fully_valid(active_cache_tree))
604 cache_tree_update(&the_index, WRITE_TREE_SILENT | WRITE_TREE_REPAIR);
605
606 if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
607 die(_("unable to write new index file"));
608
609 if (!opts->force && !opts->quiet)
610 show_local_changes(&new_branch_info->commit->object, &opts->diff_options);
611
612 return 0;
613 }
614
615 static void report_tracking(struct branch_info *new_branch_info)
616 {
617 struct strbuf sb = STRBUF_INIT;
618 struct branch *branch = branch_get(new_branch_info->name);
619
620 if (!format_tracking_info(branch, &sb, AHEAD_BEHIND_FULL))
621 return;
622 fputs(sb.buf, stdout);
623 strbuf_release(&sb);
624 }
625
626 static void update_refs_for_switch(const struct checkout_opts *opts,
627 struct branch_info *old_branch_info,
628 struct branch_info *new_branch_info)
629 {
630 struct strbuf msg = STRBUF_INIT;
631 const char *old_desc, *reflog_msg;
632 if (opts->new_branch) {
633 if (opts->new_orphan_branch) {
634 char *refname;
635
636 refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
637 if (opts->new_branch_log &&
638 !should_autocreate_reflog(refname)) {
639 int ret;
640 struct strbuf err = STRBUF_INIT;
641
642 ret = safe_create_reflog(refname, 1, &err);
643 if (ret) {
644 fprintf(stderr, _("Can not do reflog for '%s': %s\n"),
645 opts->new_orphan_branch, err.buf);
646 strbuf_release(&err);
647 free(refname);
648 return;
649 }
650 strbuf_release(&err);
651 }
652 free(refname);
653 }
654 else
655 create_branch(opts->new_branch, new_branch_info->name,
656 opts->new_branch_force ? 1 : 0,
657 opts->new_branch_force ? 1 : 0,
658 opts->new_branch_log,
659 opts->quiet,
660 opts->track);
661 new_branch_info->name = opts->new_branch;
662 setup_branch_path(new_branch_info);
663 }
664
665 old_desc = old_branch_info->name;
666 if (!old_desc && old_branch_info->commit)
667 old_desc = oid_to_hex(&old_branch_info->commit->object.oid);
668
669 reflog_msg = getenv("GIT_REFLOG_ACTION");
670 if (!reflog_msg)
671 strbuf_addf(&msg, "checkout: moving from %s to %s",
672 old_desc ? old_desc : "(invalid)", new_branch_info->name);
673 else
674 strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
675
676 if (!strcmp(new_branch_info->name, "HEAD") && !new_branch_info->path && !opts->force_detach) {
677 /* Nothing to do. */
678 } else if (opts->force_detach || !new_branch_info->path) { /* No longer on any branch. */
679 update_ref(msg.buf, "HEAD", &new_branch_info->commit->object.oid, NULL,
680 REF_NO_DEREF, UPDATE_REFS_DIE_ON_ERR);
681 if (!opts->quiet) {
682 if (old_branch_info->path &&
683 advice_detached_head && !opts->force_detach)
684 detach_advice(new_branch_info->name);
685 describe_detached_head(_("HEAD is now at"), new_branch_info->commit);
686 }
687 } else if (new_branch_info->path) { /* Switch branches. */
688 if (create_symref("HEAD", new_branch_info->path, msg.buf) < 0)
689 die(_("unable to update HEAD"));
690 if (!opts->quiet) {
691 if (old_branch_info->path && !strcmp(new_branch_info->path, old_branch_info->path)) {
692 if (opts->new_branch_force)
693 fprintf(stderr, _("Reset branch '%s'\n"),
694 new_branch_info->name);
695 else
696 fprintf(stderr, _("Already on '%s'\n"),
697 new_branch_info->name);
698 } else if (opts->new_branch) {
699 if (opts->branch_exists)
700 fprintf(stderr, _("Switched to and reset branch '%s'\n"), new_branch_info->name);
701 else
702 fprintf(stderr, _("Switched to a new branch '%s'\n"), new_branch_info->name);
703 } else {
704 fprintf(stderr, _("Switched to branch '%s'\n"),
705 new_branch_info->name);
706 }
707 }
708 if (old_branch_info->path && old_branch_info->name) {
709 if (!ref_exists(old_branch_info->path) && reflog_exists(old_branch_info->path))
710 delete_reflog(old_branch_info->path);
711 }
712 }
713 remove_branch_state();
714 strbuf_release(&msg);
715 if (!opts->quiet &&
716 (new_branch_info->path || (!opts->force_detach && !strcmp(new_branch_info->name, "HEAD"))))
717 report_tracking(new_branch_info);
718 }
719
720 static int add_pending_uninteresting_ref(const char *refname,
721 const struct object_id *oid,
722 int flags, void *cb_data)
723 {
724 add_pending_oid(cb_data, refname, oid, UNINTERESTING);
725 return 0;
726 }
727
728 static void describe_one_orphan(struct strbuf *sb, struct commit *commit)
729 {
730 strbuf_addstr(sb, " ");
731 strbuf_add_unique_abbrev(sb, &commit->object.oid, DEFAULT_ABBREV);
732 strbuf_addch(sb, ' ');
733 if (!parse_commit(commit))
734 pp_commit_easy(CMIT_FMT_ONELINE, commit, sb);
735 strbuf_addch(sb, '\n');
736 }
737
738 #define ORPHAN_CUTOFF 4
739 static void suggest_reattach(struct commit *commit, struct rev_info *revs)
740 {
741 struct commit *c, *last = NULL;
742 struct strbuf sb = STRBUF_INIT;
743 int lost = 0;
744 while ((c = get_revision(revs)) != NULL) {
745 if (lost < ORPHAN_CUTOFF)
746 describe_one_orphan(&sb, c);
747 last = c;
748 lost++;
749 }
750 if (ORPHAN_CUTOFF < lost) {
751 int more = lost - ORPHAN_CUTOFF;
752 if (more == 1)
753 describe_one_orphan(&sb, last);
754 else
755 strbuf_addf(&sb, _(" ... and %d more.\n"), more);
756 }
757
758 fprintf(stderr,
759 Q_(
760 /* The singular version */
761 "Warning: you are leaving %d commit behind, "
762 "not connected to\n"
763 "any of your branches:\n\n"
764 "%s\n",
765 /* The plural version */
766 "Warning: you are leaving %d commits behind, "
767 "not connected to\n"
768 "any of your branches:\n\n"
769 "%s\n",
770 /* Give ngettext() the count */
771 lost),
772 lost,
773 sb.buf);
774 strbuf_release(&sb);
775
776 if (advice_detached_head)
777 fprintf(stderr,
778 Q_(
779 /* The singular version */
780 "If you want to keep it by creating a new branch, "
781 "this may be a good time\nto do so with:\n\n"
782 " git branch <new-branch-name> %s\n\n",
783 /* The plural version */
784 "If you want to keep them by creating a new branch, "
785 "this may be a good time\nto do so with:\n\n"
786 " git branch <new-branch-name> %s\n\n",
787 /* Give ngettext() the count */
788 lost),
789 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
790 }
791
792 /*
793 * We are about to leave commit that was at the tip of a detached
794 * HEAD. If it is not reachable from any ref, this is the last chance
795 * for the user to do so without resorting to reflog.
796 */
797 static void orphaned_commit_warning(struct commit *old_commit, struct commit *new_commit)
798 {
799 struct rev_info revs;
800 struct object *object = &old_commit->object;
801
802 init_revisions(&revs, NULL);
803 setup_revisions(0, NULL, &revs, NULL);
804
805 object->flags &= ~UNINTERESTING;
806 add_pending_object(&revs, object, oid_to_hex(&object->oid));
807
808 for_each_ref(add_pending_uninteresting_ref, &revs);
809 add_pending_oid(&revs, "HEAD", &new_commit->object.oid, UNINTERESTING);
810
811 if (prepare_revision_walk(&revs))
812 die(_("internal error in revision walk"));
813 if (!(old_commit->object.flags & UNINTERESTING))
814 suggest_reattach(old_commit, &revs);
815 else
816 describe_detached_head(_("Previous HEAD position was"), old_commit);
817
818 /* Clean up objects used, as they will be reused. */
819 clear_commit_marks_all(ALL_REV_FLAGS);
820 }
821
822 static int switch_branches(const struct checkout_opts *opts,
823 struct branch_info *new_branch_info)
824 {
825 int ret = 0;
826 struct branch_info old_branch_info;
827 void *path_to_free;
828 struct object_id rev;
829 int flag, writeout_error = 0;
830 memset(&old_branch_info, 0, sizeof(old_branch_info));
831 old_branch_info.path = path_to_free = resolve_refdup("HEAD", 0, &rev, &flag);
832 if (old_branch_info.path)
833 old_branch_info.commit = lookup_commit_reference_gently(the_repository, &rev, 1);
834 if (!(flag & REF_ISSYMREF))
835 old_branch_info.path = NULL;
836
837 if (old_branch_info.path)
838 skip_prefix(old_branch_info.path, "refs/heads/", &old_branch_info.name);
839
840 if (!new_branch_info->name) {
841 new_branch_info->name = "HEAD";
842 new_branch_info->commit = old_branch_info.commit;
843 if (!new_branch_info->commit)
844 die(_("You are on a branch yet to be born"));
845 parse_commit_or_die(new_branch_info->commit);
846 }
847
848 ret = merge_working_tree(opts, &old_branch_info, new_branch_info, &writeout_error);
849 if (ret) {
850 free(path_to_free);
851 return ret;
852 }
853
854 if (!opts->quiet && !old_branch_info.path && old_branch_info.commit && new_branch_info->commit != old_branch_info.commit)
855 orphaned_commit_warning(old_branch_info.commit, new_branch_info->commit);
856
857 update_refs_for_switch(opts, &old_branch_info, new_branch_info);
858
859 ret = post_checkout_hook(old_branch_info.commit, new_branch_info->commit, 1);
860 free(path_to_free);
861 return ret || writeout_error;
862 }
863
864 static int git_checkout_config(const char *var, const char *value, void *cb)
865 {
866 if (!strcmp(var, "diff.ignoresubmodules")) {
867 struct checkout_opts *opts = cb;
868 handle_ignore_submodules_arg(&opts->diff_options, value);
869 return 0;
870 }
871
872 if (starts_with(var, "submodule."))
873 return git_default_submodule_config(var, value, NULL);
874
875 return git_xmerge_config(var, value, NULL);
876 }
877
878 static int parse_branchname_arg(int argc, const char **argv,
879 int dwim_new_local_branch_ok,
880 struct branch_info *new_branch_info,
881 struct checkout_opts *opts,
882 struct object_id *rev)
883 {
884 struct tree **source_tree = &opts->source_tree;
885 const char **new_branch = &opts->new_branch;
886 int argcount = 0;
887 struct object_id branch_rev;
888 const char *arg;
889 int dash_dash_pos;
890 int has_dash_dash = 0;
891 int i;
892
893 /*
894 * case 1: git checkout <ref> -- [<paths>]
895 *
896 * <ref> must be a valid tree, everything after the '--' must be
897 * a path.
898 *
899 * case 2: git checkout -- [<paths>]
900 *
901 * everything after the '--' must be paths.
902 *
903 * case 3: git checkout <something> [--]
904 *
905 * (a) If <something> is a commit, that is to
906 * switch to the branch or detach HEAD at it. As a special case,
907 * if <something> is A...B (missing A or B means HEAD but you can
908 * omit at most one side), and if there is a unique merge base
909 * between A and B, A...B names that merge base.
910 *
911 * (b) If <something> is _not_ a commit, either "--" is present
912 * or <something> is not a path, no -t or -b was given, and
913 * and there is a tracking branch whose name is <something>
914 * in one and only one remote, then this is a short-hand to
915 * fork local <something> from that remote-tracking branch.
916 *
917 * (c) Otherwise, if "--" is present, treat it like case (1).
918 *
919 * (d) Otherwise :
920 * - if it's a reference, treat it like case (1)
921 * - else if it's a path, treat it like case (2)
922 * - else: fail.
923 *
924 * case 4: git checkout <something> <paths>
925 *
926 * The first argument must not be ambiguous.
927 * - If it's *only* a reference, treat it like case (1).
928 * - If it's only a path, treat it like case (2).
929 * - else: fail.
930 *
931 */
932 if (!argc)
933 return 0;
934
935 arg = argv[0];
936 dash_dash_pos = -1;
937 for (i = 0; i < argc; i++) {
938 if (!strcmp(argv[i], "--")) {
939 dash_dash_pos = i;
940 break;
941 }
942 }
943 if (dash_dash_pos == 0)
944 return 1; /* case (2) */
945 else if (dash_dash_pos == 1)
946 has_dash_dash = 1; /* case (3) or (1) */
947 else if (dash_dash_pos >= 2)
948 die(_("only one reference expected, %d given."), dash_dash_pos);
949
950 if (!strcmp(arg, "-"))
951 arg = "@{-1}";
952
953 if (get_oid_mb(arg, rev)) {
954 /*
955 * Either case (3) or (4), with <something> not being
956 * a commit, or an attempt to use case (1) with an
957 * invalid ref.
958 *
959 * It's likely an error, but we need to find out if
960 * we should auto-create the branch, case (3).(b).
961 */
962 int recover_with_dwim = dwim_new_local_branch_ok;
963
964 if (!has_dash_dash &&
965 (check_filename(opts->prefix, arg) || !no_wildcard(arg)))
966 recover_with_dwim = 0;
967 /*
968 * Accept "git checkout foo" and "git checkout foo --"
969 * as candidates for dwim.
970 */
971 if (!(argc == 1 && !has_dash_dash) &&
972 !(argc == 2 && has_dash_dash))
973 recover_with_dwim = 0;
974
975 if (recover_with_dwim) {
976 const char *remote = unique_tracking_name(arg, rev);
977 if (remote) {
978 *new_branch = arg;
979 arg = remote;
980 /* DWIMmed to create local branch, case (3).(b) */
981 } else {
982 recover_with_dwim = 0;
983 }
984 }
985
986 if (!recover_with_dwim) {
987 if (has_dash_dash)
988 die(_("invalid reference: %s"), arg);
989 return argcount;
990 }
991 }
992
993 /* we can't end up being in (2) anymore, eat the argument */
994 argcount++;
995 argv++;
996 argc--;
997
998 new_branch_info->name = arg;
999 setup_branch_path(new_branch_info);
1000
1001 if (!check_refname_format(new_branch_info->path, 0) &&
1002 !read_ref(new_branch_info->path, &branch_rev))
1003 oidcpy(rev, &branch_rev);
1004 else
1005 new_branch_info->path = NULL; /* not an existing branch */
1006
1007 new_branch_info->commit = lookup_commit_reference_gently(the_repository, rev, 1);
1008 if (!new_branch_info->commit) {
1009 /* not a commit */
1010 *source_tree = parse_tree_indirect(rev);
1011 } else {
1012 parse_commit_or_die(new_branch_info->commit);
1013 *source_tree = get_commit_tree(new_branch_info->commit);
1014 }
1015
1016 if (!*source_tree) /* case (1): want a tree */
1017 die(_("reference is not a tree: %s"), arg);
1018 if (!has_dash_dash) { /* case (3).(d) -> (1) */
1019 /*
1020 * Do not complain the most common case
1021 * git checkout branch
1022 * even if there happen to be a file called 'branch';
1023 * it would be extremely annoying.
1024 */
1025 if (argc)
1026 verify_non_filename(opts->prefix, arg);
1027 } else {
1028 argcount++;
1029 argv++;
1030 argc--;
1031 }
1032
1033 return argcount;
1034 }
1035
1036 static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
1037 {
1038 int status;
1039 struct strbuf branch_ref = STRBUF_INIT;
1040
1041 if (!opts->new_branch)
1042 die(_("You are on a branch yet to be born"));
1043 strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
1044 status = create_symref("HEAD", branch_ref.buf, "checkout -b");
1045 strbuf_release(&branch_ref);
1046 if (!opts->quiet)
1047 fprintf(stderr, _("Switched to a new branch '%s'\n"),
1048 opts->new_branch);
1049 return status;
1050 }
1051
1052 static int checkout_branch(struct checkout_opts *opts,
1053 struct branch_info *new_branch_info)
1054 {
1055 if (opts->pathspec.nr)
1056 die(_("paths cannot be used with switching branches"));
1057
1058 if (opts->patch_mode)
1059 die(_("'%s' cannot be used with switching branches"),
1060 "--patch");
1061
1062 if (opts->writeout_stage)
1063 die(_("'%s' cannot be used with switching branches"),
1064 "--ours/--theirs");
1065
1066 if (opts->force && opts->merge)
1067 die(_("'%s' cannot be used with '%s'"), "-f", "-m");
1068
1069 if (opts->force_detach && opts->new_branch)
1070 die(_("'%s' cannot be used with '%s'"),
1071 "--detach", "-b/-B/--orphan");
1072
1073 if (opts->new_orphan_branch) {
1074 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1075 die(_("'%s' cannot be used with '%s'"), "--orphan", "-t");
1076 } else if (opts->force_detach) {
1077 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1078 die(_("'%s' cannot be used with '%s'"), "--detach", "-t");
1079 } else if (opts->track == BRANCH_TRACK_UNSPECIFIED)
1080 opts->track = git_branch_track;
1081
1082 if (new_branch_info->name && !new_branch_info->commit)
1083 die(_("Cannot switch branch to a non-commit '%s'"),
1084 new_branch_info->name);
1085
1086 if (new_branch_info->path && !opts->force_detach && !opts->new_branch &&
1087 !opts->ignore_other_worktrees) {
1088 int flag;
1089 char *head_ref = resolve_refdup("HEAD", 0, NULL, &flag);
1090 if (head_ref &&
1091 (!(flag & REF_ISSYMREF) || strcmp(head_ref, new_branch_info->path)))
1092 die_if_checked_out(new_branch_info->path, 1);
1093 free(head_ref);
1094 }
1095
1096 if (!new_branch_info->commit && opts->new_branch) {
1097 struct object_id rev;
1098 int flag;
1099
1100 if (!read_ref_full("HEAD", 0, &rev, &flag) &&
1101 (flag & REF_ISSYMREF) && is_null_oid(&rev))
1102 return switch_unborn_to_new_branch(opts);
1103 }
1104 return switch_branches(opts, new_branch_info);
1105 }
1106
1107 int cmd_checkout(int argc, const char **argv, const char *prefix)
1108 {
1109 struct checkout_opts opts;
1110 struct branch_info new_branch_info;
1111 char *conflict_style = NULL;
1112 int dwim_new_local_branch = 1;
1113 struct option options[] = {
1114 OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
1115 OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
1116 N_("create and checkout a new branch")),
1117 OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
1118 N_("create/reset and checkout a branch")),
1119 OPT_BOOL('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
1120 OPT_BOOL(0, "detach", &opts.force_detach, N_("detach HEAD at named commit")),
1121 OPT_SET_INT('t', "track", &opts.track, N_("set upstream info for new branch"),
1122 BRANCH_TRACK_EXPLICIT),
1123 OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
1124 OPT_SET_INT_F('2', "ours", &opts.writeout_stage,
1125 N_("checkout our version for unmerged files"),
1126 2, PARSE_OPT_NONEG),
1127 OPT_SET_INT_F('3', "theirs", &opts.writeout_stage,
1128 N_("checkout their version for unmerged files"),
1129 3, PARSE_OPT_NONEG),
1130 OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)"),
1131 PARSE_OPT_NOCOMPLETE),
1132 OPT_BOOL('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),
1133 OPT_BOOL_F(0, "overwrite-ignore", &opts.overwrite_ignore,
1134 N_("update ignored files (default)"),
1135 PARSE_OPT_NOCOMPLETE),
1136 OPT_STRING(0, "conflict", &conflict_style, N_("style"),
1137 N_("conflict style (merge or diff3)")),
1138 OPT_BOOL('p', "patch", &opts.patch_mode, N_("select hunks interactively")),
1139 OPT_BOOL(0, "ignore-skip-worktree-bits", &opts.ignore_skipworktree,
1140 N_("do not limit pathspecs to sparse entries only")),
1141 OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch,
1142 N_("second guess 'git checkout <no-such-branch>'")),
1143 OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
1144 N_("do not check if another worktree is holding the given ref")),
1145 { OPTION_CALLBACK, 0, "recurse-submodules", NULL,
1146 "checkout", "control recursive updating of submodules",
1147 PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater },
1148 OPT_BOOL(0, "progress", &opts.show_progress, N_("force progress reporting")),
1149 OPT_END(),
1150 };
1151
1152 memset(&opts, 0, sizeof(opts));
1153 memset(&new_branch_info, 0, sizeof(new_branch_info));
1154 opts.overwrite_ignore = 1;
1155 opts.prefix = prefix;
1156 opts.show_progress = -1;
1157
1158 git_config(git_checkout_config, &opts);
1159
1160 opts.track = BRANCH_TRACK_UNSPECIFIED;
1161
1162 argc = parse_options(argc, argv, prefix, options, checkout_usage,
1163 PARSE_OPT_KEEP_DASHDASH);
1164
1165 if (opts.show_progress < 0) {
1166 if (opts.quiet)
1167 opts.show_progress = 0;
1168 else
1169 opts.show_progress = isatty(2);
1170 }
1171
1172 if (conflict_style) {
1173 opts.merge = 1; /* implied */
1174 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
1175 }
1176
1177 if ((!!opts.new_branch + !!opts.new_branch_force + !!opts.new_orphan_branch) > 1)
1178 die(_("-b, -B and --orphan are mutually exclusive"));
1179
1180 /*
1181 * From here on, new_branch will contain the branch to be checked out,
1182 * and new_branch_force and new_orphan_branch will tell us which one of
1183 * -b/-B/--orphan is being used.
1184 */
1185 if (opts.new_branch_force)
1186 opts.new_branch = opts.new_branch_force;
1187
1188 if (opts.new_orphan_branch)
1189 opts.new_branch = opts.new_orphan_branch;
1190
1191 /* --track without -b/-B/--orphan should DWIM */
1192 if (opts.track != BRANCH_TRACK_UNSPECIFIED && !opts.new_branch) {
1193 const char *argv0 = argv[0];
1194 if (!argc || !strcmp(argv0, "--"))
1195 die (_("--track needs a branch name"));
1196 skip_prefix(argv0, "refs/", &argv0);
1197 skip_prefix(argv0, "remotes/", &argv0);
1198 argv0 = strchr(argv0, '/');
1199 if (!argv0 || !argv0[1])
1200 die (_("Missing branch name; try -b"));
1201 opts.new_branch = argv0 + 1;
1202 }
1203
1204 /*
1205 * Extract branch name from command line arguments, so
1206 * all that is left is pathspecs.
1207 *
1208 * Handle
1209 *
1210 * 1) git checkout <tree> -- [<paths>]
1211 * 2) git checkout -- [<paths>]
1212 * 3) git checkout <something> [<paths>]
1213 *
1214 * including "last branch" syntax and DWIM-ery for names of
1215 * remote branches, erroring out for invalid or ambiguous cases.
1216 */
1217 if (argc) {
1218 struct object_id rev;
1219 int dwim_ok =
1220 !opts.patch_mode &&
1221 dwim_new_local_branch &&
1222 opts.track == BRANCH_TRACK_UNSPECIFIED &&
1223 !opts.new_branch;
1224 int n = parse_branchname_arg(argc, argv, dwim_ok,
1225 &new_branch_info, &opts, &rev);
1226 argv += n;
1227 argc -= n;
1228 }
1229
1230 if (argc) {
1231 parse_pathspec(&opts.pathspec, 0,
1232 opts.patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0,
1233 prefix, argv);
1234
1235 if (!opts.pathspec.nr)
1236 die(_("invalid path specification"));
1237
1238 /*
1239 * Try to give more helpful suggestion.
1240 * new_branch && argc > 1 will be caught later.
1241 */
1242 if (opts.new_branch && argc == 1)
1243 die(_("'%s' is not a commit and a branch '%s' cannot be created from it"),
1244 argv[0], opts.new_branch);
1245
1246 if (opts.force_detach)
1247 die(_("git checkout: --detach does not take a path argument '%s'"),
1248 argv[0]);
1249
1250 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
1251 die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\n"
1252 "checking out of the index."));
1253 }
1254
1255 if (opts.new_branch) {
1256 struct strbuf buf = STRBUF_INIT;
1257
1258 if (opts.new_branch_force)
1259 opts.branch_exists = validate_branchname(opts.new_branch, &buf);
1260 else
1261 opts.branch_exists =
1262 validate_new_branchname(opts.new_branch, &buf, 0);
1263 strbuf_release(&buf);
1264 }
1265
1266 UNLEAK(opts);
1267 if (opts.patch_mode || opts.pathspec.nr)
1268 return checkout_paths(&opts, new_branch_info.name);
1269 else
1270 return checkout_branch(&opts, &new_branch_info);
1271 }