Remove deprecated OPTION_BOOLEAN for parsing arguments
[git/git.git] / builtin / checkout.c
1 #include "cache.h"
2 #include "builtin.h"
3 #include "parse-options.h"
4 #include "refs.h"
5 #include "commit.h"
6 #include "tree.h"
7 #include "tree-walk.h"
8 #include "cache-tree.h"
9 #include "unpack-trees.h"
10 #include "dir.h"
11 #include "run-command.h"
12 #include "merge-recursive.h"
13 #include "branch.h"
14 #include "diff.h"
15 #include "revision.h"
16 #include "remote.h"
17 #include "blob.h"
18 #include "xdiff-interface.h"
19 #include "ll-merge.h"
20 #include "resolve-undo.h"
21 #include "submodule.h"
22 #include "argv-array.h"
23
24 static const char * const checkout_usage[] = {
25 N_("git checkout [options] <branch>"),
26 N_("git checkout [options] [<branch>] -- <file>..."),
27 NULL,
28 };
29
30 struct checkout_opts {
31 int patch_mode;
32 int quiet;
33 int merge;
34 int force;
35 int force_detach;
36 int writeout_stage;
37 int overwrite_ignore;
38 int ignore_skipworktree;
39
40 const char *new_branch;
41 const char *new_branch_force;
42 const char *new_orphan_branch;
43 int new_branch_log;
44 enum branch_track track;
45 struct diff_options diff_options;
46
47 int branch_exists;
48 const char *prefix;
49 const char **pathspec;
50 struct tree *source_tree;
51 };
52
53 static int post_checkout_hook(struct commit *old, struct commit *new,
54 int changed)
55 {
56 return run_hook(NULL, "post-checkout",
57 sha1_to_hex(old ? old->object.sha1 : null_sha1),
58 sha1_to_hex(new ? new->object.sha1 : null_sha1),
59 changed ? "1" : "0", NULL);
60 /* "new" can be NULL when checking out from the index before
61 a commit exists. */
62
63 }
64
65 static int update_some(const unsigned char *sha1, const char *base, int baselen,
66 const char *pathname, unsigned mode, int stage, void *context)
67 {
68 int len;
69 struct cache_entry *ce;
70
71 if (S_ISDIR(mode))
72 return READ_TREE_RECURSIVE;
73
74 len = baselen + strlen(pathname);
75 ce = xcalloc(1, cache_entry_size(len));
76 hashcpy(ce->sha1, sha1);
77 memcpy(ce->name, base, baselen);
78 memcpy(ce->name + baselen, pathname, len - baselen);
79 ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
80 ce->ce_namelen = len;
81 ce->ce_mode = create_ce_mode(mode);
82 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
83 return 0;
84 }
85
86 static int read_tree_some(struct tree *tree, const char **pathspec)
87 {
88 struct pathspec ps;
89 init_pathspec(&ps, pathspec);
90 read_tree_recursive(tree, "", 0, 0, &ps, update_some, NULL);
91 free_pathspec(&ps);
92
93 /* update the index with the given tree's info
94 * for all args, expanding wildcards, and exit
95 * with any non-zero return code.
96 */
97 return 0;
98 }
99
100 static int skip_same_name(const struct cache_entry *ce, int pos)
101 {
102 while (++pos < active_nr &&
103 !strcmp(active_cache[pos]->name, ce->name))
104 ; /* skip */
105 return pos;
106 }
107
108 static int check_stage(int stage, const struct cache_entry *ce, int pos)
109 {
110 while (pos < active_nr &&
111 !strcmp(active_cache[pos]->name, ce->name)) {
112 if (ce_stage(active_cache[pos]) == stage)
113 return 0;
114 pos++;
115 }
116 if (stage == 2)
117 return error(_("path '%s' does not have our version"), ce->name);
118 else
119 return error(_("path '%s' does not have their version"), ce->name);
120 }
121
122 static int check_stages(unsigned stages, const struct cache_entry *ce, int pos)
123 {
124 unsigned seen = 0;
125 const char *name = ce->name;
126
127 while (pos < active_nr) {
128 ce = active_cache[pos];
129 if (strcmp(name, ce->name))
130 break;
131 seen |= (1 << ce_stage(ce));
132 pos++;
133 }
134 if ((stages & seen) != stages)
135 return error(_("path '%s' does not have all necessary versions"),
136 name);
137 return 0;
138 }
139
140 static int checkout_stage(int stage, struct cache_entry *ce, int pos,
141 struct checkout *state)
142 {
143 while (pos < active_nr &&
144 !strcmp(active_cache[pos]->name, ce->name)) {
145 if (ce_stage(active_cache[pos]) == stage)
146 return checkout_entry(active_cache[pos], state, NULL);
147 pos++;
148 }
149 if (stage == 2)
150 return error(_("path '%s' does not have our version"), ce->name);
151 else
152 return error(_("path '%s' does not have their version"), ce->name);
153 }
154
155 static int checkout_merged(int pos, struct checkout *state)
156 {
157 struct cache_entry *ce = active_cache[pos];
158 const char *path = ce->name;
159 mmfile_t ancestor, ours, theirs;
160 int status;
161 unsigned char sha1[20];
162 mmbuffer_t result_buf;
163 unsigned char threeway[3][20];
164 unsigned mode = 0;
165
166 memset(threeway, 0, sizeof(threeway));
167 while (pos < active_nr) {
168 int stage;
169 stage = ce_stage(ce);
170 if (!stage || strcmp(path, ce->name))
171 break;
172 hashcpy(threeway[stage - 1], ce->sha1);
173 if (stage == 2)
174 mode = create_ce_mode(ce->ce_mode);
175 pos++;
176 ce = active_cache[pos];
177 }
178 if (is_null_sha1(threeway[1]) || is_null_sha1(threeway[2]))
179 return error(_("path '%s' does not have necessary versions"), path);
180
181 read_mmblob(&ancestor, threeway[0]);
182 read_mmblob(&ours, threeway[1]);
183 read_mmblob(&theirs, threeway[2]);
184
185 /*
186 * NEEDSWORK: re-create conflicts from merges with
187 * merge.renormalize set, too
188 */
189 status = ll_merge(&result_buf, path, &ancestor, "base",
190 &ours, "ours", &theirs, "theirs", NULL);
191 free(ancestor.ptr);
192 free(ours.ptr);
193 free(theirs.ptr);
194 if (status < 0 || !result_buf.ptr) {
195 free(result_buf.ptr);
196 return error(_("path '%s': cannot merge"), path);
197 }
198
199 /*
200 * NEEDSWORK:
201 * There is absolutely no reason to write this as a blob object
202 * and create a phony cache entry just to leak. This hack is
203 * primarily to get to the write_entry() machinery that massages
204 * the contents to work-tree format and writes out which only
205 * allows it for a cache entry. The code in write_entry() needs
206 * to be refactored to allow us to feed a <buffer, size, mode>
207 * instead of a cache entry. Such a refactoring would help
208 * merge_recursive as well (it also writes the merge result to the
209 * object database even when it may contain conflicts).
210 */
211 if (write_sha1_file(result_buf.ptr, result_buf.size,
212 blob_type, sha1))
213 die(_("Unable to add merge result for '%s'"), path);
214 ce = make_cache_entry(mode, sha1, path, 2, 0);
215 if (!ce)
216 die(_("make_cache_entry failed for path '%s'"), path);
217 status = checkout_entry(ce, state, NULL);
218 return status;
219 }
220
221 static int checkout_paths(const struct checkout_opts *opts,
222 const char *revision)
223 {
224 int pos;
225 struct checkout state;
226 static char *ps_matched;
227 unsigned char rev[20];
228 int flag;
229 struct commit *head;
230 int errs = 0;
231 int stage = opts->writeout_stage;
232 int merge = opts->merge;
233 int newfd;
234 struct lock_file *lock_file;
235
236 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
237 die(_("'%s' cannot be used with updating paths"), "--track");
238
239 if (opts->new_branch_log)
240 die(_("'%s' cannot be used with updating paths"), "-l");
241
242 if (opts->force && opts->patch_mode)
243 die(_("'%s' cannot be used with updating paths"), "-f");
244
245 if (opts->force_detach)
246 die(_("'%s' cannot be used with updating paths"), "--detach");
247
248 if (opts->merge && opts->patch_mode)
249 die(_("'%s' cannot be used with %s"), "--merge", "--patch");
250
251 if (opts->force && opts->merge)
252 die(_("'%s' cannot be used with %s"), "-f", "-m");
253
254 if (opts->new_branch)
255 die(_("Cannot update paths and switch to branch '%s' at the same time."),
256 opts->new_branch);
257
258 if (opts->patch_mode)
259 return run_add_interactive(revision, "--patch=checkout",
260 opts->pathspec);
261
262 lock_file = xcalloc(1, sizeof(struct lock_file));
263
264 newfd = hold_locked_index(lock_file, 1);
265 if (read_cache_preload(opts->pathspec) < 0)
266 return error(_("corrupt index file"));
267
268 if (opts->source_tree)
269 read_tree_some(opts->source_tree, opts->pathspec);
270
271 for (pos = 0; opts->pathspec[pos]; pos++)
272 ;
273 ps_matched = xcalloc(1, pos);
274
275 /*
276 * Make sure all pathspecs participated in locating the paths
277 * to be checked out.
278 */
279 for (pos = 0; pos < active_nr; pos++) {
280 struct cache_entry *ce = active_cache[pos];
281 ce->ce_flags &= ~CE_MATCHED;
282 if (!opts->ignore_skipworktree && ce_skip_worktree(ce))
283 continue;
284 if (opts->source_tree && !(ce->ce_flags & CE_UPDATE))
285 /*
286 * "git checkout tree-ish -- path", but this entry
287 * is in the original index; it will not be checked
288 * out to the working tree and it does not matter
289 * if pathspec matched this entry. We will not do
290 * anything to this entry at all.
291 */
292 continue;
293 /*
294 * Either this entry came from the tree-ish we are
295 * checking the paths out of, or we are checking out
296 * of the index.
297 *
298 * If it comes from the tree-ish, we already know it
299 * matches the pathspec and could just stamp
300 * CE_MATCHED to it from update_some(). But we still
301 * need ps_matched and read_tree_recursive (and
302 * eventually tree_entry_interesting) cannot fill
303 * ps_matched yet. Once it can, we can avoid calling
304 * match_pathspec() for _all_ entries when
305 * opts->source_tree != NULL.
306 */
307 if (match_pathspec(opts->pathspec, ce->name, ce_namelen(ce),
308 0, ps_matched))
309 ce->ce_flags |= CE_MATCHED;
310 }
311
312 if (report_path_error(ps_matched, opts->pathspec, opts->prefix)) {
313 free(ps_matched);
314 return 1;
315 }
316 free(ps_matched);
317
318 /* "checkout -m path" to recreate conflicted state */
319 if (opts->merge)
320 unmerge_marked_index(&the_index);
321
322 /* Any unmerged paths? */
323 for (pos = 0; pos < active_nr; pos++) {
324 const struct cache_entry *ce = active_cache[pos];
325 if (ce->ce_flags & CE_MATCHED) {
326 if (!ce_stage(ce))
327 continue;
328 if (opts->force) {
329 warning(_("path '%s' is unmerged"), ce->name);
330 } else if (stage) {
331 errs |= check_stage(stage, ce, pos);
332 } else if (opts->merge) {
333 errs |= check_stages((1<<2) | (1<<3), ce, pos);
334 } else {
335 errs = 1;
336 error(_("path '%s' is unmerged"), ce->name);
337 }
338 pos = skip_same_name(ce, pos) - 1;
339 }
340 }
341 if (errs)
342 return 1;
343
344 /* Now we are committed to check them out */
345 memset(&state, 0, sizeof(state));
346 state.force = 1;
347 state.refresh_cache = 1;
348 for (pos = 0; pos < active_nr; pos++) {
349 struct cache_entry *ce = active_cache[pos];
350 if (ce->ce_flags & CE_MATCHED) {
351 if (!ce_stage(ce)) {
352 errs |= checkout_entry(ce, &state, NULL);
353 continue;
354 }
355 if (stage)
356 errs |= checkout_stage(stage, ce, pos, &state);
357 else if (merge)
358 errs |= checkout_merged(pos, &state);
359 pos = skip_same_name(ce, pos) - 1;
360 }
361 }
362
363 if (write_cache(newfd, active_cache, active_nr) ||
364 commit_locked_index(lock_file))
365 die(_("unable to write new index file"));
366
367 read_ref_full("HEAD", rev, 0, &flag);
368 head = lookup_commit_reference_gently(rev, 1);
369
370 errs |= post_checkout_hook(head, head, 0);
371 return errs;
372 }
373
374 static void show_local_changes(struct object *head,
375 const struct diff_options *opts)
376 {
377 struct rev_info rev;
378 /* I think we want full paths, even if we're in a subdirectory. */
379 init_revisions(&rev, NULL);
380 rev.diffopt.flags = opts->flags;
381 rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
382 diff_setup_done(&rev.diffopt);
383 add_pending_object(&rev, head, NULL);
384 run_diff_index(&rev, 0);
385 }
386
387 static void describe_detached_head(const char *msg, struct commit *commit)
388 {
389 struct strbuf sb = STRBUF_INIT;
390 parse_commit(commit);
391 pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
392 fprintf(stderr, "%s %s... %s\n", msg,
393 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
394 strbuf_release(&sb);
395 }
396
397 static int reset_tree(struct tree *tree, const struct checkout_opts *o,
398 int worktree, int *writeout_error)
399 {
400 struct unpack_trees_options opts;
401 struct tree_desc tree_desc;
402
403 memset(&opts, 0, sizeof(opts));
404 opts.head_idx = -1;
405 opts.update = worktree;
406 opts.skip_unmerged = !worktree;
407 opts.reset = 1;
408 opts.merge = 1;
409 opts.fn = oneway_merge;
410 opts.verbose_update = !o->quiet && isatty(2);
411 opts.src_index = &the_index;
412 opts.dst_index = &the_index;
413 parse_tree(tree);
414 init_tree_desc(&tree_desc, tree->buffer, tree->size);
415 switch (unpack_trees(1, &tree_desc, &opts)) {
416 case -2:
417 *writeout_error = 1;
418 /*
419 * We return 0 nevertheless, as the index is all right
420 * and more importantly we have made best efforts to
421 * update paths in the work tree, and we cannot revert
422 * them.
423 */
424 case 0:
425 return 0;
426 default:
427 return 128;
428 }
429 }
430
431 struct branch_info {
432 const char *name; /* The short name used */
433 const char *path; /* The full name of a real branch */
434 struct commit *commit; /* The named commit */
435 };
436
437 static void setup_branch_path(struct branch_info *branch)
438 {
439 struct strbuf buf = STRBUF_INIT;
440
441 strbuf_branchname(&buf, branch->name);
442 if (strcmp(buf.buf, branch->name))
443 branch->name = xstrdup(buf.buf);
444 strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
445 branch->path = strbuf_detach(&buf, NULL);
446 }
447
448 static int merge_working_tree(const struct checkout_opts *opts,
449 struct branch_info *old,
450 struct branch_info *new,
451 int *writeout_error)
452 {
453 int ret;
454 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
455 int newfd = hold_locked_index(lock_file, 1);
456
457 if (read_cache_preload(NULL) < 0)
458 return error(_("corrupt index file"));
459
460 resolve_undo_clear();
461 if (opts->force) {
462 ret = reset_tree(new->commit->tree, opts, 1, writeout_error);
463 if (ret)
464 return ret;
465 } else {
466 struct tree_desc trees[2];
467 struct tree *tree;
468 struct unpack_trees_options topts;
469
470 memset(&topts, 0, sizeof(topts));
471 topts.head_idx = -1;
472 topts.src_index = &the_index;
473 topts.dst_index = &the_index;
474
475 setup_unpack_trees_porcelain(&topts, "checkout");
476
477 refresh_cache(REFRESH_QUIET);
478
479 if (unmerged_cache()) {
480 error(_("you need to resolve your current index first"));
481 return 1;
482 }
483
484 /* 2-way merge to the new branch */
485 topts.initial_checkout = is_cache_unborn();
486 topts.update = 1;
487 topts.merge = 1;
488 topts.gently = opts->merge && old->commit;
489 topts.verbose_update = !opts->quiet && isatty(2);
490 topts.fn = twoway_merge;
491 if (opts->overwrite_ignore) {
492 topts.dir = xcalloc(1, sizeof(*topts.dir));
493 topts.dir->flags |= DIR_SHOW_IGNORED;
494 setup_standard_excludes(topts.dir);
495 }
496 tree = parse_tree_indirect(old->commit ?
497 old->commit->object.sha1 :
498 EMPTY_TREE_SHA1_BIN);
499 init_tree_desc(&trees[0], tree->buffer, tree->size);
500 tree = parse_tree_indirect(new->commit->object.sha1);
501 init_tree_desc(&trees[1], tree->buffer, tree->size);
502
503 ret = unpack_trees(2, trees, &topts);
504 if (ret == -1) {
505 /*
506 * Unpack couldn't do a trivial merge; either
507 * give up or do a real merge, depending on
508 * whether the merge flag was used.
509 */
510 struct tree *result;
511 struct tree *work;
512 struct merge_options o;
513 if (!opts->merge)
514 return 1;
515
516 /*
517 * Without old->commit, the below is the same as
518 * the two-tree unpack we already tried and failed.
519 */
520 if (!old->commit)
521 return 1;
522
523 /* Do more real merge */
524
525 /*
526 * We update the index fully, then write the
527 * tree from the index, then merge the new
528 * branch with the current tree, with the old
529 * branch as the base. Then we reset the index
530 * (but not the working tree) to the new
531 * branch, leaving the working tree as the
532 * merged version, but skipping unmerged
533 * entries in the index.
534 */
535
536 add_files_to_cache(NULL, NULL, 0);
537 /*
538 * NEEDSWORK: carrying over local changes
539 * when branches have different end-of-line
540 * normalization (or clean+smudge rules) is
541 * a pain; plumb in an option to set
542 * o.renormalize?
543 */
544 init_merge_options(&o);
545 o.verbosity = 0;
546 work = write_tree_from_memory(&o);
547
548 ret = reset_tree(new->commit->tree, opts, 1,
549 writeout_error);
550 if (ret)
551 return ret;
552 o.ancestor = old->name;
553 o.branch1 = new->name;
554 o.branch2 = "local";
555 merge_trees(&o, new->commit->tree, work,
556 old->commit->tree, &result);
557 ret = reset_tree(new->commit->tree, opts, 0,
558 writeout_error);
559 if (ret)
560 return ret;
561 }
562 }
563
564 if (write_cache(newfd, active_cache, active_nr) ||
565 commit_locked_index(lock_file))
566 die(_("unable to write new index file"));
567
568 if (!opts->force && !opts->quiet)
569 show_local_changes(&new->commit->object, &opts->diff_options);
570
571 return 0;
572 }
573
574 static void report_tracking(struct branch_info *new)
575 {
576 struct strbuf sb = STRBUF_INIT;
577 struct branch *branch = branch_get(new->name);
578
579 if (!format_tracking_info(branch, &sb))
580 return;
581 fputs(sb.buf, stdout);
582 strbuf_release(&sb);
583 }
584
585 static void update_refs_for_switch(const struct checkout_opts *opts,
586 struct branch_info *old,
587 struct branch_info *new)
588 {
589 struct strbuf msg = STRBUF_INIT;
590 const char *old_desc, *reflog_msg;
591 if (opts->new_branch) {
592 if (opts->new_orphan_branch) {
593 if (opts->new_branch_log && !log_all_ref_updates) {
594 int temp;
595 char log_file[PATH_MAX];
596 char *ref_name = mkpath("refs/heads/%s", opts->new_orphan_branch);
597
598 temp = log_all_ref_updates;
599 log_all_ref_updates = 1;
600 if (log_ref_setup(ref_name, log_file, sizeof(log_file))) {
601 fprintf(stderr, _("Can not do reflog for '%s'\n"),
602 opts->new_orphan_branch);
603 log_all_ref_updates = temp;
604 return;
605 }
606 log_all_ref_updates = temp;
607 }
608 }
609 else
610 create_branch(old->name, opts->new_branch, new->name,
611 opts->new_branch_force ? 1 : 0,
612 opts->new_branch_log,
613 opts->new_branch_force ? 1 : 0,
614 opts->quiet,
615 opts->track);
616 new->name = opts->new_branch;
617 setup_branch_path(new);
618 }
619
620 old_desc = old->name;
621 if (!old_desc && old->commit)
622 old_desc = sha1_to_hex(old->commit->object.sha1);
623
624 reflog_msg = getenv("GIT_REFLOG_ACTION");
625 if (!reflog_msg)
626 strbuf_addf(&msg, "checkout: moving from %s to %s",
627 old_desc ? old_desc : "(invalid)", new->name);
628 else
629 strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
630
631 if (!strcmp(new->name, "HEAD") && !new->path && !opts->force_detach) {
632 /* Nothing to do. */
633 } else if (opts->force_detach || !new->path) { /* No longer on any branch. */
634 update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
635 REF_NODEREF, DIE_ON_ERR);
636 if (!opts->quiet) {
637 if (old->path && advice_detached_head)
638 detach_advice(new->name);
639 describe_detached_head(_("HEAD is now at"), new->commit);
640 }
641 } else if (new->path) { /* Switch branches. */
642 create_symref("HEAD", new->path, msg.buf);
643 if (!opts->quiet) {
644 if (old->path && !strcmp(new->path, old->path)) {
645 if (opts->new_branch_force)
646 fprintf(stderr, _("Reset branch '%s'\n"),
647 new->name);
648 else
649 fprintf(stderr, _("Already on '%s'\n"),
650 new->name);
651 } else if (opts->new_branch) {
652 if (opts->branch_exists)
653 fprintf(stderr, _("Switched to and reset branch '%s'\n"), new->name);
654 else
655 fprintf(stderr, _("Switched to a new branch '%s'\n"), new->name);
656 } else {
657 fprintf(stderr, _("Switched to branch '%s'\n"),
658 new->name);
659 }
660 }
661 if (old->path && old->name) {
662 char log_file[PATH_MAX], ref_file[PATH_MAX];
663
664 git_snpath(log_file, sizeof(log_file), "logs/%s", old->path);
665 git_snpath(ref_file, sizeof(ref_file), "%s", old->path);
666 if (!file_exists(ref_file) && file_exists(log_file))
667 remove_path(log_file);
668 }
669 }
670 remove_branch_state();
671 strbuf_release(&msg);
672 if (!opts->quiet &&
673 (new->path || (!opts->force_detach && !strcmp(new->name, "HEAD"))))
674 report_tracking(new);
675 }
676
677 static int add_pending_uninteresting_ref(const char *refname,
678 const unsigned char *sha1,
679 int flags, void *cb_data)
680 {
681 add_pending_sha1(cb_data, refname, sha1, UNINTERESTING);
682 return 0;
683 }
684
685 static void describe_one_orphan(struct strbuf *sb, struct commit *commit)
686 {
687 parse_commit(commit);
688 strbuf_addstr(sb, " ");
689 strbuf_addstr(sb,
690 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
691 strbuf_addch(sb, ' ');
692 pp_commit_easy(CMIT_FMT_ONELINE, commit, sb);
693 strbuf_addch(sb, '\n');
694 }
695
696 #define ORPHAN_CUTOFF 4
697 static void suggest_reattach(struct commit *commit, struct rev_info *revs)
698 {
699 struct commit *c, *last = NULL;
700 struct strbuf sb = STRBUF_INIT;
701 int lost = 0;
702 while ((c = get_revision(revs)) != NULL) {
703 if (lost < ORPHAN_CUTOFF)
704 describe_one_orphan(&sb, c);
705 last = c;
706 lost++;
707 }
708 if (ORPHAN_CUTOFF < lost) {
709 int more = lost - ORPHAN_CUTOFF;
710 if (more == 1)
711 describe_one_orphan(&sb, last);
712 else
713 strbuf_addf(&sb, _(" ... and %d more.\n"), more);
714 }
715
716 fprintf(stderr,
717 Q_(
718 /* The singular version */
719 "Warning: you are leaving %d commit behind, "
720 "not connected to\n"
721 "any of your branches:\n\n"
722 "%s\n",
723 /* The plural version */
724 "Warning: you are leaving %d commits behind, "
725 "not connected to\n"
726 "any of your branches:\n\n"
727 "%s\n",
728 /* Give ngettext() the count */
729 lost),
730 lost,
731 sb.buf);
732 strbuf_release(&sb);
733
734 if (advice_detached_head)
735 fprintf(stderr,
736 _(
737 "If you want to keep them by creating a new branch, "
738 "this may be a good time\nto do so with:\n\n"
739 " git branch new_branch_name %s\n\n"),
740 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
741 }
742
743 /*
744 * We are about to leave commit that was at the tip of a detached
745 * HEAD. If it is not reachable from any ref, this is the last chance
746 * for the user to do so without resorting to reflog.
747 */
748 static void orphaned_commit_warning(struct commit *old, struct commit *new)
749 {
750 struct rev_info revs;
751 struct object *object = &old->object;
752 struct object_array refs;
753
754 init_revisions(&revs, NULL);
755 setup_revisions(0, NULL, &revs, NULL);
756
757 object->flags &= ~UNINTERESTING;
758 add_pending_object(&revs, object, sha1_to_hex(object->sha1));
759
760 for_each_ref(add_pending_uninteresting_ref, &revs);
761 add_pending_sha1(&revs, "HEAD", new->object.sha1, UNINTERESTING);
762
763 refs = revs.pending;
764 revs.leak_pending = 1;
765
766 if (prepare_revision_walk(&revs))
767 die(_("internal error in revision walk"));
768 if (!(old->object.flags & UNINTERESTING))
769 suggest_reattach(old, &revs);
770 else
771 describe_detached_head(_("Previous HEAD position was"), old);
772
773 clear_commit_marks_for_object_array(&refs, ALL_REV_FLAGS);
774 free(refs.objects);
775 }
776
777 static int switch_branches(const struct checkout_opts *opts,
778 struct branch_info *new)
779 {
780 int ret = 0;
781 struct branch_info old;
782 void *path_to_free;
783 unsigned char rev[20];
784 int flag, writeout_error = 0;
785 memset(&old, 0, sizeof(old));
786 old.path = path_to_free = resolve_refdup("HEAD", rev, 0, &flag);
787 old.commit = lookup_commit_reference_gently(rev, 1);
788 if (!(flag & REF_ISSYMREF))
789 old.path = NULL;
790
791 if (old.path && !prefixcmp(old.path, "refs/heads/"))
792 old.name = old.path + strlen("refs/heads/");
793
794 if (!new->name) {
795 new->name = "HEAD";
796 new->commit = old.commit;
797 if (!new->commit)
798 die(_("You are on a branch yet to be born"));
799 parse_commit(new->commit);
800 }
801
802 ret = merge_working_tree(opts, &old, new, &writeout_error);
803 if (ret) {
804 free(path_to_free);
805 return ret;
806 }
807
808 if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
809 orphaned_commit_warning(old.commit, new->commit);
810
811 update_refs_for_switch(opts, &old, new);
812
813 ret = post_checkout_hook(old.commit, new->commit, 1);
814 free(path_to_free);
815 return ret || writeout_error;
816 }
817
818 static int git_checkout_config(const char *var, const char *value, void *cb)
819 {
820 if (!strcmp(var, "diff.ignoresubmodules")) {
821 struct checkout_opts *opts = cb;
822 handle_ignore_submodules_arg(&opts->diff_options, value);
823 return 0;
824 }
825
826 if (!prefixcmp(var, "submodule."))
827 return parse_submodule_config_option(var, value);
828
829 return git_xmerge_config(var, value, NULL);
830 }
831
832 struct tracking_name_data {
833 /* const */ char *src_ref;
834 char *dst_ref;
835 unsigned char *dst_sha1;
836 int unique;
837 };
838
839 static int check_tracking_name(struct remote *remote, void *cb_data)
840 {
841 struct tracking_name_data *cb = cb_data;
842 struct refspec query;
843 memset(&query, 0, sizeof(struct refspec));
844 query.src = cb->src_ref;
845 if (remote_find_tracking(remote, &query) ||
846 get_sha1(query.dst, cb->dst_sha1)) {
847 free(query.dst);
848 return 0;
849 }
850 if (cb->dst_ref) {
851 free(query.dst);
852 cb->unique = 0;
853 return 0;
854 }
855 cb->dst_ref = query.dst;
856 return 0;
857 }
858
859 static const char *unique_tracking_name(const char *name, unsigned char *sha1)
860 {
861 struct tracking_name_data cb_data = { NULL, NULL, NULL, 1 };
862 char src_ref[PATH_MAX];
863 snprintf(src_ref, PATH_MAX, "refs/heads/%s", name);
864 cb_data.src_ref = src_ref;
865 cb_data.dst_sha1 = sha1;
866 for_each_remote(check_tracking_name, &cb_data);
867 if (cb_data.unique)
868 return cb_data.dst_ref;
869 free(cb_data.dst_ref);
870 return NULL;
871 }
872
873 static int parse_branchname_arg(int argc, const char **argv,
874 int dwim_new_local_branch_ok,
875 struct branch_info *new,
876 struct tree **source_tree,
877 unsigned char rev[20],
878 const char **new_branch)
879 {
880 int argcount = 0;
881 unsigned char branch_rev[20];
882 const char *arg;
883 int has_dash_dash;
884
885 /*
886 * case 1: git checkout <ref> -- [<paths>]
887 *
888 * <ref> must be a valid tree, everything after the '--' must be
889 * a path.
890 *
891 * case 2: git checkout -- [<paths>]
892 *
893 * everything after the '--' must be paths.
894 *
895 * case 3: git checkout <something> [<paths>]
896 *
897 * With no paths, if <something> is a commit, that is to
898 * switch to the branch or detach HEAD at it. As a special case,
899 * if <something> is A...B (missing A or B means HEAD but you can
900 * omit at most one side), and if there is a unique merge base
901 * between A and B, A...B names that merge base.
902 *
903 * With no paths, if <something> is _not_ a commit, no -t nor -b
904 * was given, and there is a tracking branch whose name is
905 * <something> in one and only one remote, then this is a short-hand
906 * to fork local <something> from that remote-tracking branch.
907 *
908 * Otherwise <something> shall not be ambiguous.
909 * - If it's *only* a reference, treat it like case (1).
910 * - If it's only a path, treat it like case (2).
911 * - else: fail.
912 *
913 */
914 if (!argc)
915 return 0;
916
917 if (!strcmp(argv[0], "--")) /* case (2) */
918 return 1;
919
920 arg = argv[0];
921 has_dash_dash = (argc > 1) && !strcmp(argv[1], "--");
922
923 if (!strcmp(arg, "-"))
924 arg = "@{-1}";
925
926 if (get_sha1_mb(arg, rev)) {
927 if (has_dash_dash) /* case (1) */
928 die(_("invalid reference: %s"), arg);
929 if (dwim_new_local_branch_ok &&
930 !check_filename(NULL, arg) &&
931 argc == 1) {
932 const char *remote = unique_tracking_name(arg, rev);
933 if (!remote)
934 return argcount;
935 *new_branch = arg;
936 arg = remote;
937 /* DWIMmed to create local branch */
938 } else {
939 return argcount;
940 }
941 }
942
943 /* we can't end up being in (2) anymore, eat the argument */
944 argcount++;
945 argv++;
946 argc--;
947
948 new->name = arg;
949 setup_branch_path(new);
950
951 if (!check_refname_format(new->path, 0) &&
952 !read_ref(new->path, branch_rev))
953 hashcpy(rev, branch_rev);
954 else
955 new->path = NULL; /* not an existing branch */
956
957 new->commit = lookup_commit_reference_gently(rev, 1);
958 if (!new->commit) {
959 /* not a commit */
960 *source_tree = parse_tree_indirect(rev);
961 } else {
962 parse_commit(new->commit);
963 *source_tree = new->commit->tree;
964 }
965
966 if (!*source_tree) /* case (1): want a tree */
967 die(_("reference is not a tree: %s"), arg);
968 if (!has_dash_dash) {/* case (3 -> 1) */
969 /*
970 * Do not complain the most common case
971 * git checkout branch
972 * even if there happen to be a file called 'branch';
973 * it would be extremely annoying.
974 */
975 if (argc)
976 verify_non_filename(NULL, arg);
977 } else {
978 argcount++;
979 argv++;
980 argc--;
981 }
982
983 return argcount;
984 }
985
986 static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
987 {
988 int status;
989 struct strbuf branch_ref = STRBUF_INIT;
990
991 if (!opts->new_branch)
992 die(_("You are on a branch yet to be born"));
993 strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
994 status = create_symref("HEAD", branch_ref.buf, "checkout -b");
995 strbuf_release(&branch_ref);
996 if (!opts->quiet)
997 fprintf(stderr, _("Switched to a new branch '%s'\n"),
998 opts->new_branch);
999 return status;
1000 }
1001
1002 static int checkout_branch(struct checkout_opts *opts,
1003 struct branch_info *new)
1004 {
1005 if (opts->pathspec)
1006 die(_("paths cannot be used with switching branches"));
1007
1008 if (opts->patch_mode)
1009 die(_("'%s' cannot be used with switching branches"),
1010 "--patch");
1011
1012 if (opts->writeout_stage)
1013 die(_("'%s' cannot be used with switching branches"),
1014 "--ours/--theirs");
1015
1016 if (opts->force && opts->merge)
1017 die(_("'%s' cannot be used with '%s'"), "-f", "-m");
1018
1019 if (opts->force_detach && opts->new_branch)
1020 die(_("'%s' cannot be used with '%s'"),
1021 "--detach", "-b/-B/--orphan");
1022
1023 if (opts->new_orphan_branch) {
1024 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1025 die(_("'%s' cannot be used with '%s'"), "--orphan", "-t");
1026 } else if (opts->force_detach) {
1027 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1028 die(_("'%s' cannot be used with '%s'"), "--detach", "-t");
1029 } else if (opts->track == BRANCH_TRACK_UNSPECIFIED)
1030 opts->track = git_branch_track;
1031
1032 if (new->name && !new->commit)
1033 die(_("Cannot switch branch to a non-commit '%s'"),
1034 new->name);
1035
1036 if (!new->commit && opts->new_branch) {
1037 unsigned char rev[20];
1038 int flag;
1039
1040 if (!read_ref_full("HEAD", rev, 0, &flag) &&
1041 (flag & REF_ISSYMREF) && is_null_sha1(rev))
1042 return switch_unborn_to_new_branch(opts);
1043 }
1044 return switch_branches(opts, new);
1045 }
1046
1047 int cmd_checkout(int argc, const char **argv, const char *prefix)
1048 {
1049 struct checkout_opts opts;
1050 struct branch_info new;
1051 char *conflict_style = NULL;
1052 int dwim_new_local_branch = 1;
1053 struct option options[] = {
1054 OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
1055 OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
1056 N_("create and checkout a new branch")),
1057 OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
1058 N_("create/reset and checkout a branch")),
1059 OPT_BOOLEAN('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
1060 OPT_BOOLEAN(0, "detach", &opts.force_detach, N_("detach the HEAD at named commit")),
1061 OPT_SET_INT('t', "track", &opts.track, N_("set upstream info for new branch"),
1062 BRANCH_TRACK_EXPLICIT),
1063 OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new branch"), N_("new unparented branch")),
1064 OPT_SET_INT('2', "ours", &opts.writeout_stage, N_("checkout our version for unmerged files"),
1065 2),
1066 OPT_SET_INT('3', "theirs", &opts.writeout_stage, N_("checkout their version for unmerged files"),
1067 3),
1068 OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)")),
1069 OPT_BOOLEAN('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),
1070 OPT_BOOLEAN(0, "overwrite-ignore", &opts.overwrite_ignore, N_("update ignored files (default)")),
1071 OPT_STRING(0, "conflict", &conflict_style, N_("style"),
1072 N_("conflict style (merge or diff3)")),
1073 OPT_BOOLEAN('p', "patch", &opts.patch_mode, N_("select hunks interactively")),
1074 OPT_BOOL(0, "ignore-skip-worktree-bits", &opts.ignore_skipworktree,
1075 N_("do not limit pathspecs to sparse entries only")),
1076 OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch,
1077 N_("second guess 'git checkout no-such-branch'")),
1078 OPT_END(),
1079 };
1080
1081 memset(&opts, 0, sizeof(opts));
1082 memset(&new, 0, sizeof(new));
1083 opts.overwrite_ignore = 1;
1084 opts.prefix = prefix;
1085
1086 gitmodules_config();
1087 git_config(git_checkout_config, &opts);
1088
1089 opts.track = BRANCH_TRACK_UNSPECIFIED;
1090
1091 argc = parse_options(argc, argv, prefix, options, checkout_usage,
1092 PARSE_OPT_KEEP_DASHDASH);
1093
1094 if (conflict_style) {
1095 opts.merge = 1; /* implied */
1096 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
1097 }
1098
1099 if ((!!opts.new_branch + !!opts.new_branch_force + !!opts.new_orphan_branch) > 1)
1100 die(_("-b, -B and --orphan are mutually exclusive"));
1101
1102 /*
1103 * From here on, new_branch will contain the branch to be checked out,
1104 * and new_branch_force and new_orphan_branch will tell us which one of
1105 * -b/-B/--orphan is being used.
1106 */
1107 if (opts.new_branch_force)
1108 opts.new_branch = opts.new_branch_force;
1109
1110 if (opts.new_orphan_branch)
1111 opts.new_branch = opts.new_orphan_branch;
1112
1113 /* --track without -b/-B/--orphan should DWIM */
1114 if (opts.track != BRANCH_TRACK_UNSPECIFIED && !opts.new_branch) {
1115 const char *argv0 = argv[0];
1116 if (!argc || !strcmp(argv0, "--"))
1117 die (_("--track needs a branch name"));
1118 if (!prefixcmp(argv0, "refs/"))
1119 argv0 += 5;
1120 if (!prefixcmp(argv0, "remotes/"))
1121 argv0 += 8;
1122 argv0 = strchr(argv0, '/');
1123 if (!argv0 || !argv0[1])
1124 die (_("Missing branch name; try -b"));
1125 opts.new_branch = argv0 + 1;
1126 }
1127
1128 /*
1129 * Extract branch name from command line arguments, so
1130 * all that is left is pathspecs.
1131 *
1132 * Handle
1133 *
1134 * 1) git checkout <tree> -- [<paths>]
1135 * 2) git checkout -- [<paths>]
1136 * 3) git checkout <something> [<paths>]
1137 *
1138 * including "last branch" syntax and DWIM-ery for names of
1139 * remote branches, erroring out for invalid or ambiguous cases.
1140 */
1141 if (argc) {
1142 unsigned char rev[20];
1143 int dwim_ok =
1144 !opts.patch_mode &&
1145 dwim_new_local_branch &&
1146 opts.track == BRANCH_TRACK_UNSPECIFIED &&
1147 !opts.new_branch;
1148 int n = parse_branchname_arg(argc, argv, dwim_ok,
1149 &new, &opts.source_tree,
1150 rev, &opts.new_branch);
1151 argv += n;
1152 argc -= n;
1153 }
1154
1155 if (argc) {
1156 opts.pathspec = get_pathspec(prefix, argv);
1157
1158 if (!opts.pathspec)
1159 die(_("invalid path specification"));
1160
1161 /*
1162 * Try to give more helpful suggestion.
1163 * new_branch && argc > 1 will be caught later.
1164 */
1165 if (opts.new_branch && argc == 1)
1166 die(_("Cannot update paths and switch to branch '%s' at the same time.\n"
1167 "Did you intend to checkout '%s' which can not be resolved as commit?"),
1168 opts.new_branch, argv[0]);
1169
1170 if (opts.force_detach)
1171 die(_("git checkout: --detach does not take a path argument '%s'"),
1172 argv[0]);
1173
1174 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
1175 die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\n"
1176 "checking out of the index."));
1177 }
1178
1179 if (opts.new_branch) {
1180 struct strbuf buf = STRBUF_INIT;
1181
1182 opts.branch_exists =
1183 validate_new_branchname(opts.new_branch, &buf,
1184 !!opts.new_branch_force,
1185 !!opts.new_branch_force);
1186
1187 strbuf_release(&buf);
1188 }
1189
1190 if (opts.patch_mode || opts.pathspec)
1191 return checkout_paths(&opts, new.name);
1192 else
1193 return checkout_branch(&opts, &new);
1194 }