Update messages in preparation for i18n
[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 "commit.h"
8 #include "tree.h"
9 #include "tree-walk.h"
10 #include "cache-tree.h"
11 #include "unpack-trees.h"
12 #include "dir.h"
13 #include "run-command.h"
14 #include "merge-recursive.h"
15 #include "branch.h"
16 #include "diff.h"
17 #include "revision.h"
18 #include "remote.h"
19 #include "blob.h"
20 #include "xdiff-interface.h"
21 #include "ll-merge.h"
22 #include "resolve-undo.h"
23 #include "submodule-config.h"
24 #include "submodule.h"
25
26 static const char * const checkout_usage[] = {
27 N_("git checkout [<options>] <branch>"),
28 N_("git checkout [<options>] [<branch>] -- <file>..."),
29 NULL,
30 };
31
32 struct checkout_opts {
33 int patch_mode;
34 int quiet;
35 int merge;
36 int force;
37 int force_detach;
38 int writeout_stage;
39 int overwrite_ignore;
40 int ignore_skipworktree;
41 int ignore_other_worktrees;
42 int show_progress;
43
44 const char *new_branch;
45 const char *new_branch_force;
46 const char *new_orphan_branch;
47 int new_branch_log;
48 enum branch_track track;
49 struct diff_options diff_options;
50
51 int branch_exists;
52 const char *prefix;
53 struct pathspec pathspec;
54 struct tree *source_tree;
55 };
56
57 static int post_checkout_hook(struct commit *old_commit, struct commit *new_commit,
58 int changed)
59 {
60 return run_hook_le(NULL, "post-checkout",
61 oid_to_hex(old_commit ? &old_commit->object.oid : &null_oid),
62 oid_to_hex(new_commit ? &new_commit->object.oid : &null_oid),
63 changed ? "1" : "0", NULL);
64 /* "new_commit" can be NULL when checking out from the index before
65 a commit exists. */
66
67 }
68
69 static int update_some(const struct object_id *oid, struct strbuf *base,
70 const char *pathname, unsigned mode, int stage, void *context)
71 {
72 int len;
73 struct cache_entry *ce;
74 int pos;
75
76 if (S_ISDIR(mode))
77 return READ_TREE_RECURSIVE;
78
79 len = base->len + strlen(pathname);
80 ce = xcalloc(1, cache_entry_size(len));
81 oidcpy(&ce->oid, oid);
82 memcpy(ce->name, base->buf, base->len);
83 memcpy(ce->name + base->len, pathname, len - base->len);
84 ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
85 ce->ce_namelen = len;
86 ce->ce_mode = create_ce_mode(mode);
87
88 /*
89 * If the entry is the same as the current index, we can leave the old
90 * entry in place. Whether it is UPTODATE or not, checkout_entry will
91 * do the right thing.
92 */
93 pos = cache_name_pos(ce->name, ce->ce_namelen);
94 if (pos >= 0) {
95 struct cache_entry *old = active_cache[pos];
96 if (ce->ce_mode == old->ce_mode &&
97 !oidcmp(&ce->oid, &old->oid)) {
98 old->ce_flags |= CE_UPDATE;
99 free(ce);
100 return 0;
101 }
102 }
103
104 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
105 return 0;
106 }
107
108 static int read_tree_some(struct tree *tree, const struct pathspec *pathspec)
109 {
110 read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
111
112 /* update the index with the given tree's info
113 * for all args, expanding wildcards, and exit
114 * with any non-zero return code.
115 */
116 return 0;
117 }
118
119 static int skip_same_name(const struct cache_entry *ce, int pos)
120 {
121 while (++pos < active_nr &&
122 !strcmp(active_cache[pos]->name, ce->name))
123 ; /* skip */
124 return pos;
125 }
126
127 static int check_stage(int stage, const struct cache_entry *ce, int pos)
128 {
129 while (pos < active_nr &&
130 !strcmp(active_cache[pos]->name, ce->name)) {
131 if (ce_stage(active_cache[pos]) == stage)
132 return 0;
133 pos++;
134 }
135 if (stage == 2)
136 return error(_("path '%s' does not have our version"), ce->name);
137 else
138 return error(_("path '%s' does not have their version"), ce->name);
139 }
140
141 static int check_stages(unsigned stages, const struct cache_entry *ce, int pos)
142 {
143 unsigned seen = 0;
144 const char *name = ce->name;
145
146 while (pos < active_nr) {
147 ce = active_cache[pos];
148 if (strcmp(name, ce->name))
149 break;
150 seen |= (1 << ce_stage(ce));
151 pos++;
152 }
153 if ((stages & seen) != stages)
154 return error(_("path '%s' does not have all necessary versions"),
155 name);
156 return 0;
157 }
158
159 static int checkout_stage(int stage, const struct cache_entry *ce, int pos,
160 const struct checkout *state)
161 {
162 while (pos < active_nr &&
163 !strcmp(active_cache[pos]->name, ce->name)) {
164 if (ce_stage(active_cache[pos]) == stage)
165 return checkout_entry(active_cache[pos], state, NULL);
166 pos++;
167 }
168 if (stage == 2)
169 return error(_("path '%s' does not have our version"), ce->name);
170 else
171 return error(_("path '%s' does not have their version"), ce->name);
172 }
173
174 static int checkout_merged(int pos, const struct checkout *state)
175 {
176 struct cache_entry *ce = active_cache[pos];
177 const char *path = ce->name;
178 mmfile_t ancestor, ours, theirs;
179 int status;
180 struct object_id oid;
181 mmbuffer_t result_buf;
182 struct object_id threeway[3];
183 unsigned mode = 0;
184
185 memset(threeway, 0, sizeof(threeway));
186 while (pos < active_nr) {
187 int stage;
188 stage = ce_stage(ce);
189 if (!stage || strcmp(path, ce->name))
190 break;
191 oidcpy(&threeway[stage - 1], &ce->oid);
192 if (stage == 2)
193 mode = create_ce_mode(ce->ce_mode);
194 pos++;
195 ce = active_cache[pos];
196 }
197 if (is_null_oid(&threeway[1]) || is_null_oid(&threeway[2]))
198 return error(_("path '%s' does not have necessary versions"), path);
199
200 read_mmblob(&ancestor, &threeway[0]);
201 read_mmblob(&ours, &threeway[1]);
202 read_mmblob(&theirs, &threeway[2]);
203
204 /*
205 * NEEDSWORK: re-create conflicts from merges with
206 * merge.renormalize set, too
207 */
208 status = ll_merge(&result_buf, path, &ancestor, "base",
209 &ours, "ours", &theirs, "theirs", NULL);
210 free(ancestor.ptr);
211 free(ours.ptr);
212 free(theirs.ptr);
213 if (status < 0 || !result_buf.ptr) {
214 free(result_buf.ptr);
215 return error(_("path '%s': cannot merge"), path);
216 }
217
218 /*
219 * NEEDSWORK:
220 * There is absolutely no reason to write this as a blob object
221 * and create a phony cache entry. This hack is primarily to get
222 * to the write_entry() machinery that massages the contents to
223 * work-tree format and writes out which only allows it for a
224 * cache entry. The code in write_entry() needs to be refactored
225 * to allow us to feed a <buffer, size, mode> instead of a cache
226 * entry. Such a refactoring would help merge_recursive as well
227 * (it also writes the merge result to the object database even
228 * when it may contain conflicts).
229 */
230 if (write_object_file(result_buf.ptr, result_buf.size, blob_type, &oid))
231 die(_("Unable to add merge result for '%s'"), path);
232 free(result_buf.ptr);
233 ce = make_cache_entry(mode, oid.hash, path, 2, 0);
234 if (!ce)
235 die(_("make_cache_entry failed for path '%s'"), path);
236 status = checkout_entry(ce, state, NULL);
237 free(ce);
238 return status;
239 }
240
241 static int checkout_paths(const struct checkout_opts *opts,
242 const char *revision)
243 {
244 int pos;
245 struct checkout state = CHECKOUT_INIT;
246 static char *ps_matched;
247 struct object_id rev;
248 struct commit *head;
249 int errs = 0;
250 struct lock_file lock_file = LOCK_INIT;
251
252 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
253 die(_("'%s' cannot be used with updating paths"), "--track");
254
255 if (opts->new_branch_log)
256 die(_("'%s' cannot be used with updating paths"), "-l");
257
258 if (opts->force && opts->patch_mode)
259 die(_("'%s' cannot be used with updating paths"), "-f");
260
261 if (opts->force_detach)
262 die(_("'%s' cannot be used with updating paths"), "--detach");
263
264 if (opts->merge && opts->patch_mode)
265 die(_("'%s' cannot be used with %s"), "--merge", "--patch");
266
267 if (opts->force && opts->merge)
268 die(_("'%s' cannot be used with %s"), "-f", "-m");
269
270 if (opts->new_branch)
271 die(_("Cannot update paths and switch to branch '%s' at the same time."),
272 opts->new_branch);
273
274 if (opts->patch_mode)
275 return run_add_interactive(revision, "--patch=checkout",
276 &opts->pathspec);
277
278 hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
279 if (read_cache_preload(&opts->pathspec) < 0)
280 return error(_("index file corrupt"));
281
282 if (opts->source_tree)
283 read_tree_some(opts->source_tree, &opts->pathspec);
284
285 ps_matched = xcalloc(opts->pathspec.nr, 1);
286
287 /*
288 * Make sure all pathspecs participated in locating the paths
289 * to be checked out.
290 */
291 for (pos = 0; pos < active_nr; pos++) {
292 struct cache_entry *ce = active_cache[pos];
293 ce->ce_flags &= ~CE_MATCHED;
294 if (!opts->ignore_skipworktree && ce_skip_worktree(ce))
295 continue;
296 if (opts->source_tree && !(ce->ce_flags & CE_UPDATE))
297 /*
298 * "git checkout tree-ish -- path", but this entry
299 * is in the original index; it will not be checked
300 * out to the working tree and it does not matter
301 * if pathspec matched this entry. We will not do
302 * anything to this entry at all.
303 */
304 continue;
305 /*
306 * Either this entry came from the tree-ish we are
307 * checking the paths out of, or we are checking out
308 * of the index.
309 *
310 * If it comes from the tree-ish, we already know it
311 * matches the pathspec and could just stamp
312 * CE_MATCHED to it from update_some(). But we still
313 * need ps_matched and read_tree_recursive (and
314 * eventually tree_entry_interesting) cannot fill
315 * ps_matched yet. Once it can, we can avoid calling
316 * match_pathspec() for _all_ entries when
317 * opts->source_tree != NULL.
318 */
319 if (ce_path_match(ce, &opts->pathspec, ps_matched))
320 ce->ce_flags |= CE_MATCHED;
321 }
322
323 if (report_path_error(ps_matched, &opts->pathspec, opts->prefix)) {
324 free(ps_matched);
325 return 1;
326 }
327 free(ps_matched);
328
329 /* "checkout -m path" to recreate conflicted state */
330 if (opts->merge)
331 unmerge_marked_index(&the_index);
332
333 /* Any unmerged paths? */
334 for (pos = 0; pos < active_nr; pos++) {
335 const struct cache_entry *ce = active_cache[pos];
336 if (ce->ce_flags & CE_MATCHED) {
337 if (!ce_stage(ce))
338 continue;
339 if (opts->force) {
340 warning(_("path '%s' is unmerged"), ce->name);
341 } else if (opts->writeout_stage) {
342 errs |= check_stage(opts->writeout_stage, ce, pos);
343 } else if (opts->merge) {
344 errs |= check_stages((1<<2) | (1<<3), ce, pos);
345 } else {
346 errs = 1;
347 error(_("path '%s' is unmerged"), ce->name);
348 }
349 pos = skip_same_name(ce, pos) - 1;
350 }
351 }
352 if (errs)
353 return 1;
354
355 /* Now we are committed to check them out */
356 state.force = 1;
357 state.refresh_cache = 1;
358 state.istate = &the_index;
359
360 enable_delayed_checkout(&state);
361 for (pos = 0; pos < active_nr; pos++) {
362 struct cache_entry *ce = active_cache[pos];
363 if (ce->ce_flags & CE_MATCHED) {
364 if (!ce_stage(ce)) {
365 errs |= checkout_entry(ce, &state, NULL);
366 continue;
367 }
368 if (opts->writeout_stage)
369 errs |= checkout_stage(opts->writeout_stage, ce, pos, &state);
370 else if (opts->merge)
371 errs |= checkout_merged(pos, &state);
372 pos = skip_same_name(ce, pos) - 1;
373 }
374 }
375 errs |= finish_delayed_checkout(&state);
376
377 if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
378 die(_("unable to write new index file"));
379
380 read_ref_full("HEAD", 0, &rev, NULL);
381 head = lookup_commit_reference_gently(&rev, 1);
382
383 errs |= post_checkout_hook(head, head, 0);
384 return errs;
385 }
386
387 static void show_local_changes(struct object *head,
388 const struct diff_options *opts)
389 {
390 struct rev_info rev;
391 /* I think we want full paths, even if we're in a subdirectory. */
392 init_revisions(&rev, NULL);
393 rev.diffopt.flags = opts->flags;
394 rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
395 diff_setup_done(&rev.diffopt);
396 add_pending_object(&rev, head, NULL);
397 run_diff_index(&rev, 0);
398 }
399
400 static void describe_detached_head(const char *msg, struct commit *commit)
401 {
402 struct strbuf sb = STRBUF_INIT;
403
404 if (!parse_commit(commit))
405 pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
406 if (print_sha1_ellipsis()) {
407 fprintf(stderr, "%s %s... %s\n", msg,
408 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV), sb.buf);
409 } else {
410 fprintf(stderr, "%s %s %s\n", msg,
411 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV), sb.buf);
412 }
413 strbuf_release(&sb);
414 }
415
416 static int reset_tree(struct tree *tree, const struct checkout_opts *o,
417 int worktree, int *writeout_error)
418 {
419 struct unpack_trees_options opts;
420 struct tree_desc tree_desc;
421
422 memset(&opts, 0, sizeof(opts));
423 opts.head_idx = -1;
424 opts.update = worktree;
425 opts.skip_unmerged = !worktree;
426 opts.reset = 1;
427 opts.merge = 1;
428 opts.fn = oneway_merge;
429 opts.verbose_update = o->show_progress;
430 opts.src_index = &the_index;
431 opts.dst_index = &the_index;
432 parse_tree(tree);
433 init_tree_desc(&tree_desc, tree->buffer, tree->size);
434 switch (unpack_trees(1, &tree_desc, &opts)) {
435 case -2:
436 *writeout_error = 1;
437 /*
438 * We return 0 nevertheless, as the index is all right
439 * and more importantly we have made best efforts to
440 * update paths in the work tree, and we cannot revert
441 * them.
442 */
443 /* fallthrough */
444 case 0:
445 return 0;
446 default:
447 return 128;
448 }
449 }
450
451 struct branch_info {
452 const char *name; /* The short name used */
453 const char *path; /* The full name of a real branch */
454 struct commit *commit; /* The named commit */
455 /*
456 * if not null the branch is detached because it's already
457 * checked out in this checkout
458 */
459 char *checkout;
460 };
461
462 static void setup_branch_path(struct branch_info *branch)
463 {
464 struct strbuf buf = STRBUF_INIT;
465
466 strbuf_branchname(&buf, branch->name, INTERPRET_BRANCH_LOCAL);
467 if (strcmp(buf.buf, branch->name))
468 branch->name = xstrdup(buf.buf);
469 strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
470 branch->path = strbuf_detach(&buf, NULL);
471 }
472
473 static int merge_working_tree(const struct checkout_opts *opts,
474 struct branch_info *old_branch_info,
475 struct branch_info *new_branch_info,
476 int *writeout_error)
477 {
478 int ret;
479 struct lock_file lock_file = LOCK_INIT;
480
481 hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
482 if (read_cache_preload(NULL) < 0)
483 return error(_("index file corrupt"));
484
485 resolve_undo_clear();
486 if (opts->force) {
487 ret = reset_tree(get_commit_tree(new_branch_info->commit),
488 opts, 1, writeout_error);
489 if (ret)
490 return ret;
491 } else {
492 struct tree_desc trees[2];
493 struct tree *tree;
494 struct unpack_trees_options topts;
495
496 memset(&topts, 0, sizeof(topts));
497 topts.head_idx = -1;
498 topts.src_index = &the_index;
499 topts.dst_index = &the_index;
500
501 setup_unpack_trees_porcelain(&topts, "checkout");
502
503 refresh_cache(REFRESH_QUIET);
504
505 if (unmerged_cache()) {
506 error(_("you need to resolve your current index first"));
507 return 1;
508 }
509
510 /* 2-way merge to the new branch */
511 topts.initial_checkout = is_cache_unborn();
512 topts.update = 1;
513 topts.merge = 1;
514 topts.gently = opts->merge && old_branch_info->commit;
515 topts.verbose_update = opts->show_progress;
516 topts.fn = twoway_merge;
517 if (opts->overwrite_ignore) {
518 topts.dir = xcalloc(1, sizeof(*topts.dir));
519 topts.dir->flags |= DIR_SHOW_IGNORED;
520 setup_standard_excludes(topts.dir);
521 }
522 tree = parse_tree_indirect(old_branch_info->commit ?
523 &old_branch_info->commit->object.oid :
524 the_hash_algo->empty_tree);
525 init_tree_desc(&trees[0], tree->buffer, tree->size);
526 tree = parse_tree_indirect(&new_branch_info->commit->object.oid);
527 init_tree_desc(&trees[1], tree->buffer, tree->size);
528
529 ret = unpack_trees(2, trees, &topts);
530 clear_unpack_trees_porcelain(&topts);
531 if (ret == -1) {
532 /*
533 * Unpack couldn't do a trivial merge; either
534 * give up or do a real merge, depending on
535 * whether the merge flag was used.
536 */
537 struct tree *result;
538 struct tree *work;
539 struct merge_options o;
540 if (!opts->merge)
541 return 1;
542
543 /*
544 * Without old_branch_info->commit, the below is the same as
545 * the two-tree unpack we already tried and failed.
546 */
547 if (!old_branch_info->commit)
548 return 1;
549
550 /* Do more real merge */
551
552 /*
553 * We update the index fully, then write the
554 * tree from the index, then merge the new
555 * branch with the current tree, with the old
556 * branch as the base. Then we reset the index
557 * (but not the working tree) to the new
558 * branch, leaving the working tree as the
559 * merged version, but skipping unmerged
560 * entries in the index.
561 */
562
563 add_files_to_cache(NULL, NULL, 0);
564 /*
565 * NEEDSWORK: carrying over local changes
566 * when branches have different end-of-line
567 * normalization (or clean+smudge rules) is
568 * a pain; plumb in an option to set
569 * o.renormalize?
570 */
571 init_merge_options(&o);
572 o.verbosity = 0;
573 work = write_tree_from_memory(&o);
574
575 ret = reset_tree(get_commit_tree(new_branch_info->commit),
576 opts, 1,
577 writeout_error);
578 if (ret)
579 return ret;
580 o.ancestor = old_branch_info->name;
581 o.branch1 = new_branch_info->name;
582 o.branch2 = "local";
583 ret = merge_trees(&o,
584 get_commit_tree(new_branch_info->commit),
585 work,
586 get_commit_tree(old_branch_info->commit),
587 &result);
588 if (ret < 0)
589 exit(128);
590 ret = reset_tree(get_commit_tree(new_branch_info->commit),
591 opts, 0,
592 writeout_error);
593 strbuf_release(&o.obuf);
594 if (ret)
595 return ret;
596 }
597 }
598
599 if (!active_cache_tree)
600 active_cache_tree = cache_tree();
601
602 if (!cache_tree_fully_valid(active_cache_tree))
603 cache_tree_update(&the_index, WRITE_TREE_SILENT | WRITE_TREE_REPAIR);
604
605 if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
606 die(_("unable to write new index file"));
607
608 if (!opts->force && !opts->quiet)
609 show_local_changes(&new_branch_info->commit->object, &opts->diff_options);
610
611 return 0;
612 }
613
614 static void report_tracking(struct branch_info *new_branch_info)
615 {
616 struct strbuf sb = STRBUF_INIT;
617 struct branch *branch = branch_get(new_branch_info->name);
618
619 if (!format_tracking_info(branch, &sb, AHEAD_BEHIND_FULL))
620 return;
621 fputs(sb.buf, stdout);
622 strbuf_release(&sb);
623 }
624
625 static void update_refs_for_switch(const struct checkout_opts *opts,
626 struct branch_info *old_branch_info,
627 struct branch_info *new_branch_info)
628 {
629 struct strbuf msg = STRBUF_INIT;
630 const char *old_desc, *reflog_msg;
631 if (opts->new_branch) {
632 if (opts->new_orphan_branch) {
633 char *refname;
634
635 refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
636 if (opts->new_branch_log &&
637 !should_autocreate_reflog(refname)) {
638 int ret;
639 struct strbuf err = STRBUF_INIT;
640
641 ret = safe_create_reflog(refname, 1, &err);
642 if (ret) {
643 fprintf(stderr, _("Can not do reflog for '%s': %s\n"),
644 opts->new_orphan_branch, err.buf);
645 strbuf_release(&err);
646 free(refname);
647 return;
648 }
649 strbuf_release(&err);
650 }
651 free(refname);
652 }
653 else
654 create_branch(opts->new_branch, new_branch_info->name,
655 opts->new_branch_force ? 1 : 0,
656 opts->new_branch_force ? 1 : 0,
657 opts->new_branch_log,
658 opts->quiet,
659 opts->track);
660 new_branch_info->name = opts->new_branch;
661 setup_branch_path(new_branch_info);
662 }
663
664 old_desc = old_branch_info->name;
665 if (!old_desc && old_branch_info->commit)
666 old_desc = oid_to_hex(&old_branch_info->commit->object.oid);
667
668 reflog_msg = getenv("GIT_REFLOG_ACTION");
669 if (!reflog_msg)
670 strbuf_addf(&msg, "checkout: moving from %s to %s",
671 old_desc ? old_desc : "(invalid)", new_branch_info->name);
672 else
673 strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
674
675 if (!strcmp(new_branch_info->name, "HEAD") && !new_branch_info->path && !opts->force_detach) {
676 /* Nothing to do. */
677 } else if (opts->force_detach || !new_branch_info->path) { /* No longer on any branch. */
678 update_ref(msg.buf, "HEAD", &new_branch_info->commit->object.oid, NULL,
679 REF_NO_DEREF, UPDATE_REFS_DIE_ON_ERR);
680 if (!opts->quiet) {
681 if (old_branch_info->path &&
682 advice_detached_head && !opts->force_detach)
683 detach_advice(new_branch_info->name);
684 describe_detached_head(_("HEAD is now at"), new_branch_info->commit);
685 }
686 } else if (new_branch_info->path) { /* Switch branches. */
687 if (create_symref("HEAD", new_branch_info->path, msg.buf) < 0)
688 die(_("unable to update HEAD"));
689 if (!opts->quiet) {
690 if (old_branch_info->path && !strcmp(new_branch_info->path, old_branch_info->path)) {
691 if (opts->new_branch_force)
692 fprintf(stderr, _("Reset branch '%s'\n"),
693 new_branch_info->name);
694 else
695 fprintf(stderr, _("Already on '%s'\n"),
696 new_branch_info->name);
697 } else if (opts->new_branch) {
698 if (opts->branch_exists)
699 fprintf(stderr, _("Switched to and reset branch '%s'\n"), new_branch_info->name);
700 else
701 fprintf(stderr, _("Switched to a new branch '%s'\n"), new_branch_info->name);
702 } else {
703 fprintf(stderr, _("Switched to branch '%s'\n"),
704 new_branch_info->name);
705 }
706 }
707 if (old_branch_info->path && old_branch_info->name) {
708 if (!ref_exists(old_branch_info->path) && reflog_exists(old_branch_info->path))
709 delete_reflog(old_branch_info->path);
710 }
711 }
712 remove_branch_state();
713 strbuf_release(&msg);
714 if (!opts->quiet &&
715 (new_branch_info->path || (!opts->force_detach && !strcmp(new_branch_info->name, "HEAD"))))
716 report_tracking(new_branch_info);
717 }
718
719 static int add_pending_uninteresting_ref(const char *refname,
720 const struct object_id *oid,
721 int flags, void *cb_data)
722 {
723 add_pending_oid(cb_data, refname, oid, UNINTERESTING);
724 return 0;
725 }
726
727 static void describe_one_orphan(struct strbuf *sb, struct commit *commit)
728 {
729 strbuf_addstr(sb, " ");
730 strbuf_add_unique_abbrev(sb, &commit->object.oid, DEFAULT_ABBREV);
731 strbuf_addch(sb, ' ');
732 if (!parse_commit(commit))
733 pp_commit_easy(CMIT_FMT_ONELINE, commit, sb);
734 strbuf_addch(sb, '\n');
735 }
736
737 #define ORPHAN_CUTOFF 4
738 static void suggest_reattach(struct commit *commit, struct rev_info *revs)
739 {
740 struct commit *c, *last = NULL;
741 struct strbuf sb = STRBUF_INIT;
742 int lost = 0;
743 while ((c = get_revision(revs)) != NULL) {
744 if (lost < ORPHAN_CUTOFF)
745 describe_one_orphan(&sb, c);
746 last = c;
747 lost++;
748 }
749 if (ORPHAN_CUTOFF < lost) {
750 int more = lost - ORPHAN_CUTOFF;
751 if (more == 1)
752 describe_one_orphan(&sb, last);
753 else
754 strbuf_addf(&sb, _(" ... and %d more.\n"), more);
755 }
756
757 fprintf(stderr,
758 Q_(
759 /* The singular version */
760 "Warning: you are leaving %d commit behind, "
761 "not connected to\n"
762 "any of your branches:\n\n"
763 "%s\n",
764 /* The plural version */
765 "Warning: you are leaving %d commits behind, "
766 "not connected to\n"
767 "any of your branches:\n\n"
768 "%s\n",
769 /* Give ngettext() the count */
770 lost),
771 lost,
772 sb.buf);
773 strbuf_release(&sb);
774
775 if (advice_detached_head)
776 fprintf(stderr,
777 Q_(
778 /* The singular version */
779 "If you want to keep it by creating a new branch, "
780 "this may be a good time\nto do so with:\n\n"
781 " git branch <new-branch-name> %s\n\n",
782 /* The plural version */
783 "If you want to keep them by creating a new branch, "
784 "this may be a good time\nto do so with:\n\n"
785 " git branch <new-branch-name> %s\n\n",
786 /* Give ngettext() the count */
787 lost),
788 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
789 }
790
791 /*
792 * We are about to leave commit that was at the tip of a detached
793 * HEAD. If it is not reachable from any ref, this is the last chance
794 * for the user to do so without resorting to reflog.
795 */
796 static void orphaned_commit_warning(struct commit *old_commit, struct commit *new_commit)
797 {
798 struct rev_info revs;
799 struct object *object = &old_commit->object;
800
801 init_revisions(&revs, NULL);
802 setup_revisions(0, NULL, &revs, NULL);
803
804 object->flags &= ~UNINTERESTING;
805 add_pending_object(&revs, object, oid_to_hex(&object->oid));
806
807 for_each_ref(add_pending_uninteresting_ref, &revs);
808 add_pending_oid(&revs, "HEAD", &new_commit->object.oid, UNINTERESTING);
809
810 if (prepare_revision_walk(&revs))
811 die(_("internal error in revision walk"));
812 if (!(old_commit->object.flags & UNINTERESTING))
813 suggest_reattach(old_commit, &revs);
814 else
815 describe_detached_head(_("Previous HEAD position was"), old_commit);
816
817 /* Clean up objects used, as they will be reused. */
818 clear_commit_marks_all(ALL_REV_FLAGS);
819 }
820
821 static int switch_branches(const struct checkout_opts *opts,
822 struct branch_info *new_branch_info)
823 {
824 int ret = 0;
825 struct branch_info old_branch_info;
826 void *path_to_free;
827 struct object_id rev;
828 int flag, writeout_error = 0;
829 memset(&old_branch_info, 0, sizeof(old_branch_info));
830 old_branch_info.path = path_to_free = resolve_refdup("HEAD", 0, &rev, &flag);
831 if (old_branch_info.path)
832 old_branch_info.commit = lookup_commit_reference_gently(&rev, 1);
833 if (!(flag & REF_ISSYMREF))
834 old_branch_info.path = NULL;
835
836 if (old_branch_info.path)
837 skip_prefix(old_branch_info.path, "refs/heads/", &old_branch_info.name);
838
839 if (!new_branch_info->name) {
840 new_branch_info->name = "HEAD";
841 new_branch_info->commit = old_branch_info.commit;
842 if (!new_branch_info->commit)
843 die(_("You are on a branch yet to be born"));
844 parse_commit_or_die(new_branch_info->commit);
845 }
846
847 ret = merge_working_tree(opts, &old_branch_info, new_branch_info, &writeout_error);
848 if (ret) {
849 free(path_to_free);
850 return ret;
851 }
852
853 if (!opts->quiet && !old_branch_info.path && old_branch_info.commit && new_branch_info->commit != old_branch_info.commit)
854 orphaned_commit_warning(old_branch_info.commit, new_branch_info->commit);
855
856 update_refs_for_switch(opts, &old_branch_info, new_branch_info);
857
858 ret = post_checkout_hook(old_branch_info.commit, new_branch_info->commit, 1);
859 free(path_to_free);
860 return ret || writeout_error;
861 }
862
863 static int git_checkout_config(const char *var, const char *value, void *cb)
864 {
865 if (!strcmp(var, "diff.ignoresubmodules")) {
866 struct checkout_opts *opts = cb;
867 handle_ignore_submodules_arg(&opts->diff_options, value);
868 return 0;
869 }
870
871 if (starts_with(var, "submodule."))
872 return git_default_submodule_config(var, value, NULL);
873
874 return git_xmerge_config(var, value, NULL);
875 }
876
877 static int parse_branchname_arg(int argc, const char **argv,
878 int dwim_new_local_branch_ok,
879 struct branch_info *new_branch_info,
880 struct checkout_opts *opts,
881 struct object_id *rev)
882 {
883 struct tree **source_tree = &opts->source_tree;
884 const char **new_branch = &opts->new_branch;
885 int argcount = 0;
886 struct object_id branch_rev;
887 const char *arg;
888 int dash_dash_pos;
889 int has_dash_dash = 0;
890 int i;
891
892 /*
893 * case 1: git checkout <ref> -- [<paths>]
894 *
895 * <ref> must be a valid tree, everything after the '--' must be
896 * a path.
897 *
898 * case 2: git checkout -- [<paths>]
899 *
900 * everything after the '--' must be paths.
901 *
902 * case 3: git checkout <something> [--]
903 *
904 * (a) If <something> is a commit, that is to
905 * switch to the branch or detach HEAD at it. As a special case,
906 * if <something> is A...B (missing A or B means HEAD but you can
907 * omit at most one side), and if there is a unique merge base
908 * between A and B, A...B names that merge base.
909 *
910 * (b) If <something> is _not_ a commit, either "--" is present
911 * or <something> is not a path, no -t or -b was given, and
912 * and there is a tracking branch whose name is <something>
913 * in one and only one remote, then this is a short-hand to
914 * fork local <something> from that remote-tracking branch.
915 *
916 * (c) Otherwise, if "--" is present, treat it like case (1).
917 *
918 * (d) Otherwise :
919 * - if it's a reference, treat it like case (1)
920 * - else if it's a path, treat it like case (2)
921 * - else: fail.
922 *
923 * case 4: git checkout <something> <paths>
924 *
925 * The first argument must not be ambiguous.
926 * - If it's *only* a reference, treat it like case (1).
927 * - If it's only a path, treat it like case (2).
928 * - else: fail.
929 *
930 */
931 if (!argc)
932 return 0;
933
934 arg = argv[0];
935 dash_dash_pos = -1;
936 for (i = 0; i < argc; i++) {
937 if (!strcmp(argv[i], "--")) {
938 dash_dash_pos = i;
939 break;
940 }
941 }
942 if (dash_dash_pos == 0)
943 return 1; /* case (2) */
944 else if (dash_dash_pos == 1)
945 has_dash_dash = 1; /* case (3) or (1) */
946 else if (dash_dash_pos >= 2)
947 die(_("only one reference expected, %d given."), dash_dash_pos);
948
949 if (!strcmp(arg, "-"))
950 arg = "@{-1}";
951
952 if (get_oid_mb(arg, rev)) {
953 /*
954 * Either case (3) or (4), with <something> not being
955 * a commit, or an attempt to use case (1) with an
956 * invalid ref.
957 *
958 * It's likely an error, but we need to find out if
959 * we should auto-create the branch, case (3).(b).
960 */
961 int recover_with_dwim = dwim_new_local_branch_ok;
962
963 if (!has_dash_dash &&
964 (check_filename(opts->prefix, arg) || !no_wildcard(arg)))
965 recover_with_dwim = 0;
966 /*
967 * Accept "git checkout foo" and "git checkout foo --"
968 * as candidates for dwim.
969 */
970 if (!(argc == 1 && !has_dash_dash) &&
971 !(argc == 2 && has_dash_dash))
972 recover_with_dwim = 0;
973
974 if (recover_with_dwim) {
975 const char *remote = unique_tracking_name(arg, rev);
976 if (remote) {
977 *new_branch = arg;
978 arg = remote;
979 /* DWIMmed to create local branch, case (3).(b) */
980 } else {
981 recover_with_dwim = 0;
982 }
983 }
984
985 if (!recover_with_dwim) {
986 if (has_dash_dash)
987 die(_("invalid reference: %s"), arg);
988 return argcount;
989 }
990 }
991
992 /* we can't end up being in (2) anymore, eat the argument */
993 argcount++;
994 argv++;
995 argc--;
996
997 new_branch_info->name = arg;
998 setup_branch_path(new_branch_info);
999
1000 if (!check_refname_format(new_branch_info->path, 0) &&
1001 !read_ref(new_branch_info->path, &branch_rev))
1002 oidcpy(rev, &branch_rev);
1003 else
1004 new_branch_info->path = NULL; /* not an existing branch */
1005
1006 new_branch_info->commit = lookup_commit_reference_gently(rev, 1);
1007 if (!new_branch_info->commit) {
1008 /* not a commit */
1009 *source_tree = parse_tree_indirect(rev);
1010 } else {
1011 parse_commit_or_die(new_branch_info->commit);
1012 *source_tree = get_commit_tree(new_branch_info->commit);
1013 }
1014
1015 if (!*source_tree) /* case (1): want a tree */
1016 die(_("reference is not a tree: %s"), arg);
1017 if (!has_dash_dash) { /* case (3).(d) -> (1) */
1018 /*
1019 * Do not complain the most common case
1020 * git checkout branch
1021 * even if there happen to be a file called 'branch';
1022 * it would be extremely annoying.
1023 */
1024 if (argc)
1025 verify_non_filename(opts->prefix, arg);
1026 } else {
1027 argcount++;
1028 argv++;
1029 argc--;
1030 }
1031
1032 return argcount;
1033 }
1034
1035 static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
1036 {
1037 int status;
1038 struct strbuf branch_ref = STRBUF_INIT;
1039
1040 if (!opts->new_branch)
1041 die(_("You are on a branch yet to be born"));
1042 strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
1043 status = create_symref("HEAD", branch_ref.buf, "checkout -b");
1044 strbuf_release(&branch_ref);
1045 if (!opts->quiet)
1046 fprintf(stderr, _("Switched to a new branch '%s'\n"),
1047 opts->new_branch);
1048 return status;
1049 }
1050
1051 static int checkout_branch(struct checkout_opts *opts,
1052 struct branch_info *new_branch_info)
1053 {
1054 if (opts->pathspec.nr)
1055 die(_("paths cannot be used with switching branches"));
1056
1057 if (opts->patch_mode)
1058 die(_("'%s' cannot be used with switching branches"),
1059 "--patch");
1060
1061 if (opts->writeout_stage)
1062 die(_("'%s' cannot be used with switching branches"),
1063 "--ours/--theirs");
1064
1065 if (opts->force && opts->merge)
1066 die(_("'%s' cannot be used with '%s'"), "-f", "-m");
1067
1068 if (opts->force_detach && opts->new_branch)
1069 die(_("'%s' cannot be used with '%s'"),
1070 "--detach", "-b/-B/--orphan");
1071
1072 if (opts->new_orphan_branch) {
1073 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1074 die(_("'%s' cannot be used with '%s'"), "--orphan", "-t");
1075 } else if (opts->force_detach) {
1076 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1077 die(_("'%s' cannot be used with '%s'"), "--detach", "-t");
1078 } else if (opts->track == BRANCH_TRACK_UNSPECIFIED)
1079 opts->track = git_branch_track;
1080
1081 if (new_branch_info->name && !new_branch_info->commit)
1082 die(_("Cannot switch branch to a non-commit '%s'"),
1083 new_branch_info->name);
1084
1085 if (new_branch_info->path && !opts->force_detach && !opts->new_branch &&
1086 !opts->ignore_other_worktrees) {
1087 int flag;
1088 char *head_ref = resolve_refdup("HEAD", 0, NULL, &flag);
1089 if (head_ref &&
1090 (!(flag & REF_ISSYMREF) || strcmp(head_ref, new_branch_info->path)))
1091 die_if_checked_out(new_branch_info->path, 1);
1092 free(head_ref);
1093 }
1094
1095 if (!new_branch_info->commit && opts->new_branch) {
1096 struct object_id rev;
1097 int flag;
1098
1099 if (!read_ref_full("HEAD", 0, &rev, &flag) &&
1100 (flag & REF_ISSYMREF) && is_null_oid(&rev))
1101 return switch_unborn_to_new_branch(opts);
1102 }
1103 return switch_branches(opts, new_branch_info);
1104 }
1105
1106 int cmd_checkout(int argc, const char **argv, const char *prefix)
1107 {
1108 struct checkout_opts opts;
1109 struct branch_info new_branch_info;
1110 char *conflict_style = NULL;
1111 int dwim_new_local_branch = 1;
1112 struct option options[] = {
1113 OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
1114 OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
1115 N_("create and checkout a new branch")),
1116 OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
1117 N_("create/reset and checkout a branch")),
1118 OPT_BOOL('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
1119 OPT_BOOL(0, "detach", &opts.force_detach, N_("detach HEAD at named commit")),
1120 OPT_SET_INT('t', "track", &opts.track, N_("set upstream info for new branch"),
1121 BRANCH_TRACK_EXPLICIT),
1122 OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
1123 OPT_SET_INT_F('2', "ours", &opts.writeout_stage,
1124 N_("checkout our version for unmerged files"),
1125 2, PARSE_OPT_NONEG),
1126 OPT_SET_INT_F('3', "theirs", &opts.writeout_stage,
1127 N_("checkout their version for unmerged files"),
1128 3, PARSE_OPT_NONEG),
1129 OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)"),
1130 PARSE_OPT_NOCOMPLETE),
1131 OPT_BOOL('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),
1132 OPT_BOOL_F(0, "overwrite-ignore", &opts.overwrite_ignore,
1133 N_("update ignored files (default)"),
1134 PARSE_OPT_NOCOMPLETE),
1135 OPT_STRING(0, "conflict", &conflict_style, N_("style"),
1136 N_("conflict style (merge or diff3)")),
1137 OPT_BOOL('p', "patch", &opts.patch_mode, N_("select hunks interactively")),
1138 OPT_BOOL(0, "ignore-skip-worktree-bits", &opts.ignore_skipworktree,
1139 N_("do not limit pathspecs to sparse entries only")),
1140 OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch,
1141 N_("second guess 'git checkout <no-such-branch>'")),
1142 OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
1143 N_("do not check if another worktree is holding the given ref")),
1144 { OPTION_CALLBACK, 0, "recurse-submodules", NULL,
1145 "checkout", "control recursive updating of submodules",
1146 PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater },
1147 OPT_BOOL(0, "progress", &opts.show_progress, N_("force progress reporting")),
1148 OPT_END(),
1149 };
1150
1151 memset(&opts, 0, sizeof(opts));
1152 memset(&new_branch_info, 0, sizeof(new_branch_info));
1153 opts.overwrite_ignore = 1;
1154 opts.prefix = prefix;
1155 opts.show_progress = -1;
1156
1157 git_config(git_checkout_config, &opts);
1158
1159 opts.track = BRANCH_TRACK_UNSPECIFIED;
1160
1161 argc = parse_options(argc, argv, prefix, options, checkout_usage,
1162 PARSE_OPT_KEEP_DASHDASH);
1163
1164 if (opts.show_progress < 0) {
1165 if (opts.quiet)
1166 opts.show_progress = 0;
1167 else
1168 opts.show_progress = isatty(2);
1169 }
1170
1171 if (conflict_style) {
1172 opts.merge = 1; /* implied */
1173 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
1174 }
1175
1176 if ((!!opts.new_branch + !!opts.new_branch_force + !!opts.new_orphan_branch) > 1)
1177 die(_("-b, -B and --orphan are mutually exclusive"));
1178
1179 /*
1180 * From here on, new_branch will contain the branch to be checked out,
1181 * and new_branch_force and new_orphan_branch will tell us which one of
1182 * -b/-B/--orphan is being used.
1183 */
1184 if (opts.new_branch_force)
1185 opts.new_branch = opts.new_branch_force;
1186
1187 if (opts.new_orphan_branch)
1188 opts.new_branch = opts.new_orphan_branch;
1189
1190 /* --track without -b/-B/--orphan should DWIM */
1191 if (opts.track != BRANCH_TRACK_UNSPECIFIED && !opts.new_branch) {
1192 const char *argv0 = argv[0];
1193 if (!argc || !strcmp(argv0, "--"))
1194 die(_("--track needs a branch name"));
1195 skip_prefix(argv0, "refs/", &argv0);
1196 skip_prefix(argv0, "remotes/", &argv0);
1197 argv0 = strchr(argv0, '/');
1198 if (!argv0 || !argv0[1])
1199 die(_("missing branch name; try -b"));
1200 opts.new_branch = argv0 + 1;
1201 }
1202
1203 /*
1204 * Extract branch name from command line arguments, so
1205 * all that is left is pathspecs.
1206 *
1207 * Handle
1208 *
1209 * 1) git checkout <tree> -- [<paths>]
1210 * 2) git checkout -- [<paths>]
1211 * 3) git checkout <something> [<paths>]
1212 *
1213 * including "last branch" syntax and DWIM-ery for names of
1214 * remote branches, erroring out for invalid or ambiguous cases.
1215 */
1216 if (argc) {
1217 struct object_id rev;
1218 int dwim_ok =
1219 !opts.patch_mode &&
1220 dwim_new_local_branch &&
1221 opts.track == BRANCH_TRACK_UNSPECIFIED &&
1222 !opts.new_branch;
1223 int n = parse_branchname_arg(argc, argv, dwim_ok,
1224 &new_branch_info, &opts, &rev);
1225 argv += n;
1226 argc -= n;
1227 }
1228
1229 if (argc) {
1230 parse_pathspec(&opts.pathspec, 0,
1231 opts.patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0,
1232 prefix, argv);
1233
1234 if (!opts.pathspec.nr)
1235 die(_("invalid path specification"));
1236
1237 /*
1238 * Try to give more helpful suggestion.
1239 * new_branch && argc > 1 will be caught later.
1240 */
1241 if (opts.new_branch && argc == 1)
1242 die(_("'%s' is not a commit and a branch '%s' cannot be created from it"),
1243 argv[0], opts.new_branch);
1244
1245 if (opts.force_detach)
1246 die(_("git checkout: --detach does not take a path argument '%s'"),
1247 argv[0]);
1248
1249 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
1250 die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\n"
1251 "checking out of the index."));
1252 }
1253
1254 if (opts.new_branch) {
1255 struct strbuf buf = STRBUF_INIT;
1256
1257 if (opts.new_branch_force)
1258 opts.branch_exists = validate_branchname(opts.new_branch, &buf);
1259 else
1260 opts.branch_exists =
1261 validate_new_branchname(opts.new_branch, &buf, 0);
1262 strbuf_release(&buf);
1263 }
1264
1265 UNLEAK(opts);
1266 if (opts.patch_mode || opts.pathspec.nr)
1267 return checkout_paths(&opts, new_branch_info.name);
1268 else
1269 return checkout_branch(&opts, &new_branch_info);
1270 }