refactor duplicated fill_mm() in checkout and merge-recursive
[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
22 static const char * const checkout_usage[] = {
23 "git checkout [options] <branch>",
24 "git checkout [options] [<branch>] -- <file>...",
25 NULL,
26 };
27
28 struct checkout_opts {
29 int quiet;
30 int merge;
31 int force;
32 int writeout_stage;
33 int writeout_error;
34
35 const char *new_branch;
36 int new_branch_log;
37 enum branch_track track;
38 };
39
40 static int post_checkout_hook(struct commit *old, struct commit *new,
41 int changed)
42 {
43 return run_hook(NULL, "post-checkout",
44 sha1_to_hex(old ? old->object.sha1 : null_sha1),
45 sha1_to_hex(new ? new->object.sha1 : null_sha1),
46 changed ? "1" : "0", NULL);
47 /* "new" can be NULL when checking out from the index before
48 a commit exists. */
49
50 }
51
52 static int update_some(const unsigned char *sha1, const char *base, int baselen,
53 const char *pathname, unsigned mode, int stage, void *context)
54 {
55 int len;
56 struct cache_entry *ce;
57
58 if (S_ISDIR(mode))
59 return READ_TREE_RECURSIVE;
60
61 len = baselen + strlen(pathname);
62 ce = xcalloc(1, cache_entry_size(len));
63 hashcpy(ce->sha1, sha1);
64 memcpy(ce->name, base, baselen);
65 memcpy(ce->name + baselen, pathname, len - baselen);
66 ce->ce_flags = create_ce_flags(len, 0);
67 ce->ce_mode = create_ce_mode(mode);
68 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
69 return 0;
70 }
71
72 static int read_tree_some(struct tree *tree, const char **pathspec)
73 {
74 read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
75
76 /* update the index with the given tree's info
77 * for all args, expanding wildcards, and exit
78 * with any non-zero return code.
79 */
80 return 0;
81 }
82
83 static int skip_same_name(struct cache_entry *ce, int pos)
84 {
85 while (++pos < active_nr &&
86 !strcmp(active_cache[pos]->name, ce->name))
87 ; /* skip */
88 return pos;
89 }
90
91 static int check_stage(int stage, struct cache_entry *ce, int pos)
92 {
93 while (pos < active_nr &&
94 !strcmp(active_cache[pos]->name, ce->name)) {
95 if (ce_stage(active_cache[pos]) == stage)
96 return 0;
97 pos++;
98 }
99 return error("path '%s' does not have %s version",
100 ce->name,
101 (stage == 2) ? "our" : "their");
102 }
103
104 static int check_all_stages(struct cache_entry *ce, int pos)
105 {
106 if (ce_stage(ce) != 1 ||
107 active_nr <= pos + 2 ||
108 strcmp(active_cache[pos+1]->name, ce->name) ||
109 ce_stage(active_cache[pos+1]) != 2 ||
110 strcmp(active_cache[pos+2]->name, ce->name) ||
111 ce_stage(active_cache[pos+2]) != 3)
112 return error("path '%s' does not have all three versions",
113 ce->name);
114 return 0;
115 }
116
117 static int checkout_stage(int stage, struct cache_entry *ce, int pos,
118 struct checkout *state)
119 {
120 while (pos < active_nr &&
121 !strcmp(active_cache[pos]->name, ce->name)) {
122 if (ce_stage(active_cache[pos]) == stage)
123 return checkout_entry(active_cache[pos], state, NULL);
124 pos++;
125 }
126 return error("path '%s' does not have %s version",
127 ce->name,
128 (stage == 2) ? "our" : "their");
129 }
130
131 static int checkout_merged(int pos, struct checkout *state)
132 {
133 struct cache_entry *ce = active_cache[pos];
134 const char *path = ce->name;
135 mmfile_t ancestor, ours, theirs;
136 int status;
137 unsigned char sha1[20];
138 mmbuffer_t result_buf;
139
140 if (ce_stage(ce) != 1 ||
141 active_nr <= pos + 2 ||
142 strcmp(active_cache[pos+1]->name, path) ||
143 ce_stage(active_cache[pos+1]) != 2 ||
144 strcmp(active_cache[pos+2]->name, path) ||
145 ce_stage(active_cache[pos+2]) != 3)
146 return error("path '%s' does not have all 3 versions", path);
147
148 read_mmblob(&ancestor, active_cache[pos]->sha1);
149 read_mmblob(&ours, active_cache[pos+1]->sha1);
150 read_mmblob(&theirs, active_cache[pos+2]->sha1);
151
152 status = ll_merge(&result_buf, path, &ancestor,
153 &ours, "ours", &theirs, "theirs", 0);
154 free(ancestor.ptr);
155 free(ours.ptr);
156 free(theirs.ptr);
157 if (status < 0 || !result_buf.ptr) {
158 free(result_buf.ptr);
159 return error("path '%s': cannot merge", path);
160 }
161
162 /*
163 * NEEDSWORK:
164 * There is absolutely no reason to write this as a blob object
165 * and create a phony cache entry just to leak. This hack is
166 * primarily to get to the write_entry() machinery that massages
167 * the contents to work-tree format and writes out which only
168 * allows it for a cache entry. The code in write_entry() needs
169 * to be refactored to allow us to feed a <buffer, size, mode>
170 * instead of a cache entry. Such a refactoring would help
171 * merge_recursive as well (it also writes the merge result to the
172 * object database even when it may contain conflicts).
173 */
174 if (write_sha1_file(result_buf.ptr, result_buf.size,
175 blob_type, sha1))
176 die("Unable to add merge result for '%s'", path);
177 ce = make_cache_entry(create_ce_mode(active_cache[pos+1]->ce_mode),
178 sha1,
179 path, 2, 0);
180 if (!ce)
181 die("make_cache_entry failed for path '%s'", path);
182 status = checkout_entry(ce, state, NULL);
183 return status;
184 }
185
186 static int checkout_paths(struct tree *source_tree, const char **pathspec,
187 struct checkout_opts *opts)
188 {
189 int pos;
190 struct checkout state;
191 static char *ps_matched;
192 unsigned char rev[20];
193 int flag;
194 struct commit *head;
195 int errs = 0;
196 int stage = opts->writeout_stage;
197 int merge = opts->merge;
198 int newfd;
199 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
200
201 newfd = hold_locked_index(lock_file, 1);
202 if (read_cache_preload(pathspec) < 0)
203 return error("corrupt index file");
204
205 if (source_tree)
206 read_tree_some(source_tree, pathspec);
207
208 for (pos = 0; pathspec[pos]; pos++)
209 ;
210 ps_matched = xcalloc(1, pos);
211
212 for (pos = 0; pos < active_nr; pos++) {
213 struct cache_entry *ce = active_cache[pos];
214 match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, ps_matched);
215 }
216
217 if (report_path_error(ps_matched, pathspec, 0))
218 return 1;
219
220 /* "checkout -m path" to recreate conflicted state */
221 if (opts->merge)
222 unmerge_cache(pathspec);
223
224 /* Any unmerged paths? */
225 for (pos = 0; pos < active_nr; pos++) {
226 struct cache_entry *ce = active_cache[pos];
227 if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
228 if (!ce_stage(ce))
229 continue;
230 if (opts->force) {
231 warning("path '%s' is unmerged", ce->name);
232 } else if (stage) {
233 errs |= check_stage(stage, ce, pos);
234 } else if (opts->merge) {
235 errs |= check_all_stages(ce, pos);
236 } else {
237 errs = 1;
238 error("path '%s' is unmerged", ce->name);
239 }
240 pos = skip_same_name(ce, pos) - 1;
241 }
242 }
243 if (errs)
244 return 1;
245
246 /* Now we are committed to check them out */
247 memset(&state, 0, sizeof(state));
248 state.force = 1;
249 state.refresh_cache = 1;
250 for (pos = 0; pos < active_nr; pos++) {
251 struct cache_entry *ce = active_cache[pos];
252 if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
253 if (!ce_stage(ce)) {
254 errs |= checkout_entry(ce, &state, NULL);
255 continue;
256 }
257 if (stage)
258 errs |= checkout_stage(stage, ce, pos, &state);
259 else if (merge)
260 errs |= checkout_merged(pos, &state);
261 pos = skip_same_name(ce, pos) - 1;
262 }
263 }
264
265 if (write_cache(newfd, active_cache, active_nr) ||
266 commit_locked_index(lock_file))
267 die("unable to write new index file");
268
269 resolve_ref("HEAD", rev, 0, &flag);
270 head = lookup_commit_reference_gently(rev, 1);
271
272 errs |= post_checkout_hook(head, head, 0);
273 return errs;
274 }
275
276 static void show_local_changes(struct object *head)
277 {
278 struct rev_info rev;
279 /* I think we want full paths, even if we're in a subdirectory. */
280 init_revisions(&rev, NULL);
281 rev.abbrev = 0;
282 rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
283 if (diff_setup_done(&rev.diffopt) < 0)
284 die("diff_setup_done failed");
285 add_pending_object(&rev, head, NULL);
286 run_diff_index(&rev, 0);
287 }
288
289 static void describe_detached_head(char *msg, struct commit *commit)
290 {
291 struct strbuf sb = STRBUF_INIT;
292 struct pretty_print_context ctx = {0};
293 parse_commit(commit);
294 pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, &ctx);
295 fprintf(stderr, "%s %s... %s\n", msg,
296 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
297 strbuf_release(&sb);
298 }
299
300 static int reset_tree(struct tree *tree, struct checkout_opts *o, int worktree)
301 {
302 struct unpack_trees_options opts;
303 struct tree_desc tree_desc;
304
305 memset(&opts, 0, sizeof(opts));
306 opts.head_idx = -1;
307 opts.update = worktree;
308 opts.skip_unmerged = !worktree;
309 opts.reset = 1;
310 opts.merge = 1;
311 opts.fn = oneway_merge;
312 opts.verbose_update = !o->quiet;
313 opts.src_index = &the_index;
314 opts.dst_index = &the_index;
315 parse_tree(tree);
316 init_tree_desc(&tree_desc, tree->buffer, tree->size);
317 switch (unpack_trees(1, &tree_desc, &opts)) {
318 case -2:
319 o->writeout_error = 1;
320 /*
321 * We return 0 nevertheless, as the index is all right
322 * and more importantly we have made best efforts to
323 * update paths in the work tree, and we cannot revert
324 * them.
325 */
326 case 0:
327 return 0;
328 default:
329 return 128;
330 }
331 }
332
333 struct branch_info {
334 const char *name; /* The short name used */
335 const char *path; /* The full name of a real branch */
336 struct commit *commit; /* The named commit */
337 };
338
339 static void setup_branch_path(struct branch_info *branch)
340 {
341 struct strbuf buf = STRBUF_INIT;
342
343 strbuf_branchname(&buf, branch->name);
344 if (strcmp(buf.buf, branch->name))
345 branch->name = xstrdup(buf.buf);
346 strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
347 branch->path = strbuf_detach(&buf, NULL);
348 }
349
350 static int merge_working_tree(struct checkout_opts *opts,
351 struct branch_info *old, struct branch_info *new)
352 {
353 int ret;
354 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
355 int newfd = hold_locked_index(lock_file, 1);
356
357 if (read_cache_preload(NULL) < 0)
358 return error("corrupt index file");
359
360 resolve_undo_clear();
361 if (opts->force) {
362 ret = reset_tree(new->commit->tree, opts, 1);
363 if (ret)
364 return ret;
365 } else {
366 struct tree_desc trees[2];
367 struct tree *tree;
368 struct unpack_trees_options topts;
369
370 memset(&topts, 0, sizeof(topts));
371 topts.head_idx = -1;
372 topts.src_index = &the_index;
373 topts.dst_index = &the_index;
374
375 topts.msgs.not_uptodate_file = "You have local changes to '%s'; cannot switch branches.";
376
377 refresh_cache(REFRESH_QUIET);
378
379 if (unmerged_cache()) {
380 error("you need to resolve your current index first");
381 return 1;
382 }
383
384 /* 2-way merge to the new branch */
385 topts.initial_checkout = is_cache_unborn();
386 topts.update = 1;
387 topts.merge = 1;
388 topts.gently = opts->merge && old->commit;
389 topts.verbose_update = !opts->quiet;
390 topts.fn = twoway_merge;
391 topts.dir = xcalloc(1, sizeof(*topts.dir));
392 topts.dir->flags |= DIR_SHOW_IGNORED;
393 topts.dir->exclude_per_dir = ".gitignore";
394 tree = parse_tree_indirect(old->commit ?
395 old->commit->object.sha1 :
396 (unsigned char *)EMPTY_TREE_SHA1_BIN);
397 init_tree_desc(&trees[0], tree->buffer, tree->size);
398 tree = parse_tree_indirect(new->commit->object.sha1);
399 init_tree_desc(&trees[1], tree->buffer, tree->size);
400
401 ret = unpack_trees(2, trees, &topts);
402 if (ret == -1) {
403 /*
404 * Unpack couldn't do a trivial merge; either
405 * give up or do a real merge, depending on
406 * whether the merge flag was used.
407 */
408 struct tree *result;
409 struct tree *work;
410 struct merge_options o;
411 if (!opts->merge)
412 return 1;
413
414 /*
415 * Without old->commit, the below is the same as
416 * the two-tree unpack we already tried and failed.
417 */
418 if (!old->commit)
419 return 1;
420
421 /* Do more real merge */
422
423 /*
424 * We update the index fully, then write the
425 * tree from the index, then merge the new
426 * branch with the current tree, with the old
427 * branch as the base. Then we reset the index
428 * (but not the working tree) to the new
429 * branch, leaving the working tree as the
430 * merged version, but skipping unmerged
431 * entries in the index.
432 */
433
434 add_files_to_cache(NULL, NULL, 0);
435 init_merge_options(&o);
436 o.verbosity = 0;
437 work = write_tree_from_memory(&o);
438
439 ret = reset_tree(new->commit->tree, opts, 1);
440 if (ret)
441 return ret;
442 o.branch1 = new->name;
443 o.branch2 = "local";
444 merge_trees(&o, new->commit->tree, work,
445 old->commit->tree, &result);
446 ret = reset_tree(new->commit->tree, opts, 0);
447 if (ret)
448 return ret;
449 }
450 }
451
452 if (write_cache(newfd, active_cache, active_nr) ||
453 commit_locked_index(lock_file))
454 die("unable to write new index file");
455
456 if (!opts->force && !opts->quiet)
457 show_local_changes(&new->commit->object);
458
459 return 0;
460 }
461
462 static void report_tracking(struct branch_info *new)
463 {
464 struct strbuf sb = STRBUF_INIT;
465 struct branch *branch = branch_get(new->name);
466
467 if (!format_tracking_info(branch, &sb))
468 return;
469 fputs(sb.buf, stdout);
470 strbuf_release(&sb);
471 }
472
473 static void update_refs_for_switch(struct checkout_opts *opts,
474 struct branch_info *old,
475 struct branch_info *new)
476 {
477 struct strbuf msg = STRBUF_INIT;
478 const char *old_desc;
479 if (opts->new_branch) {
480 create_branch(old->name, opts->new_branch, new->name, 0,
481 opts->new_branch_log, opts->track);
482 new->name = opts->new_branch;
483 setup_branch_path(new);
484 }
485
486 old_desc = old->name;
487 if (!old_desc && old->commit)
488 old_desc = sha1_to_hex(old->commit->object.sha1);
489 strbuf_addf(&msg, "checkout: moving from %s to %s",
490 old_desc ? old_desc : "(invalid)", new->name);
491
492 if (new->path) {
493 create_symref("HEAD", new->path, msg.buf);
494 if (!opts->quiet) {
495 if (old->path && !strcmp(new->path, old->path))
496 fprintf(stderr, "Already on '%s'\n",
497 new->name);
498 else
499 fprintf(stderr, "Switched to%s branch '%s'\n",
500 opts->new_branch ? " a new" : "",
501 new->name);
502 }
503 } else if (strcmp(new->name, "HEAD")) {
504 update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
505 REF_NODEREF, DIE_ON_ERR);
506 if (!opts->quiet) {
507 if (old->path)
508 fprintf(stderr, "Note: moving to '%s' which isn't a local branch\nIf you want to create a new branch from this checkout, you may do so\n(now or later) by using -b with the checkout command again. Example:\n git checkout -b <new_branch_name>\n", new->name);
509 describe_detached_head("HEAD is now at", new->commit);
510 }
511 }
512 remove_branch_state();
513 strbuf_release(&msg);
514 if (!opts->quiet && (new->path || !strcmp(new->name, "HEAD")))
515 report_tracking(new);
516 }
517
518 static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
519 {
520 int ret = 0;
521 struct branch_info old;
522 unsigned char rev[20];
523 int flag;
524 memset(&old, 0, sizeof(old));
525 old.path = resolve_ref("HEAD", rev, 0, &flag);
526 old.commit = lookup_commit_reference_gently(rev, 1);
527 if (!(flag & REF_ISSYMREF))
528 old.path = NULL;
529
530 if (old.path && !prefixcmp(old.path, "refs/heads/"))
531 old.name = old.path + strlen("refs/heads/");
532
533 if (!new->name) {
534 new->name = "HEAD";
535 new->commit = old.commit;
536 if (!new->commit)
537 die("You are on a branch yet to be born");
538 parse_commit(new->commit);
539 }
540
541 ret = merge_working_tree(opts, &old, new);
542 if (ret)
543 return ret;
544
545 /*
546 * If we were on a detached HEAD, but have now moved to
547 * a new commit, we want to mention the old commit once more
548 * to remind the user that it might be lost.
549 */
550 if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
551 describe_detached_head("Previous HEAD position was", old.commit);
552
553 update_refs_for_switch(opts, &old, new);
554
555 ret = post_checkout_hook(old.commit, new->commit, 1);
556 return ret || opts->writeout_error;
557 }
558
559 static int git_checkout_config(const char *var, const char *value, void *cb)
560 {
561 return git_xmerge_config(var, value, cb);
562 }
563
564 static int interactive_checkout(const char *revision, const char **pathspec,
565 struct checkout_opts *opts)
566 {
567 return run_add_interactive(revision, "--patch=checkout", pathspec);
568 }
569
570 struct tracking_name_data {
571 const char *name;
572 char *remote;
573 int unique;
574 };
575
576 static int check_tracking_name(const char *refname, const unsigned char *sha1,
577 int flags, void *cb_data)
578 {
579 struct tracking_name_data *cb = cb_data;
580 const char *slash;
581
582 if (prefixcmp(refname, "refs/remotes/"))
583 return 0;
584 slash = strchr(refname + 13, '/');
585 if (!slash || strcmp(slash + 1, cb->name))
586 return 0;
587 if (cb->remote) {
588 cb->unique = 0;
589 return 0;
590 }
591 cb->remote = xstrdup(refname);
592 return 0;
593 }
594
595 static const char *unique_tracking_name(const char *name)
596 {
597 struct tracking_name_data cb_data = { name, NULL, 1 };
598 for_each_ref(check_tracking_name, &cb_data);
599 if (cb_data.unique)
600 return cb_data.remote;
601 free(cb_data.remote);
602 return NULL;
603 }
604
605 int cmd_checkout(int argc, const char **argv, const char *prefix)
606 {
607 struct checkout_opts opts;
608 unsigned char rev[20];
609 const char *arg;
610 struct branch_info new;
611 struct tree *source_tree = NULL;
612 char *conflict_style = NULL;
613 int patch_mode = 0;
614 int dwim_new_local_branch = 1;
615 struct option options[] = {
616 OPT__QUIET(&opts.quiet),
617 OPT_STRING('b', NULL, &opts.new_branch, "new branch", "branch"),
618 OPT_BOOLEAN('l', NULL, &opts.new_branch_log, "log for new branch"),
619 OPT_SET_INT('t', "track", &opts.track, "track",
620 BRANCH_TRACK_EXPLICIT),
621 OPT_SET_INT('2', "ours", &opts.writeout_stage, "stage",
622 2),
623 OPT_SET_INT('3', "theirs", &opts.writeout_stage, "stage",
624 3),
625 OPT_BOOLEAN('f', "force", &opts.force, "force"),
626 OPT_BOOLEAN('m', "merge", &opts.merge, "merge"),
627 OPT_STRING(0, "conflict", &conflict_style, "style",
628 "conflict style (merge or diff3)"),
629 OPT_BOOLEAN('p', "patch", &patch_mode, "select hunks interactively"),
630 { OPTION_BOOLEAN, 0, "guess", &dwim_new_local_branch, NULL,
631 "second guess 'git checkout no-such-branch'",
632 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
633 OPT_END(),
634 };
635 int has_dash_dash;
636
637 memset(&opts, 0, sizeof(opts));
638 memset(&new, 0, sizeof(new));
639
640 git_config(git_checkout_config, NULL);
641
642 opts.track = BRANCH_TRACK_UNSPECIFIED;
643
644 argc = parse_options(argc, argv, prefix, options, checkout_usage,
645 PARSE_OPT_KEEP_DASHDASH);
646
647 if (patch_mode && (opts.track > 0 || opts.new_branch
648 || opts.new_branch_log || opts.merge || opts.force))
649 die ("--patch is incompatible with all other options");
650
651 /* --track without -b should DWIM */
652 if (0 < opts.track && !opts.new_branch) {
653 const char *argv0 = argv[0];
654 if (!argc || !strcmp(argv0, "--"))
655 die ("--track needs a branch name");
656 if (!prefixcmp(argv0, "refs/"))
657 argv0 += 5;
658 if (!prefixcmp(argv0, "remotes/"))
659 argv0 += 8;
660 argv0 = strchr(argv0, '/');
661 if (!argv0 || !argv0[1])
662 die ("Missing branch name; try -b");
663 opts.new_branch = argv0 + 1;
664 }
665
666 if (conflict_style) {
667 opts.merge = 1; /* implied */
668 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
669 }
670
671 if (opts.force && opts.merge)
672 die("git checkout: -f and -m are incompatible");
673
674 /*
675 * case 1: git checkout <ref> -- [<paths>]
676 *
677 * <ref> must be a valid tree, everything after the '--' must be
678 * a path.
679 *
680 * case 2: git checkout -- [<paths>]
681 *
682 * everything after the '--' must be paths.
683 *
684 * case 3: git checkout <something> [<paths>]
685 *
686 * With no paths, if <something> is a commit, that is to
687 * switch to the branch or detach HEAD at it. As a special case,
688 * if <something> is A...B (missing A or B means HEAD but you can
689 * omit at most one side), and if there is a unique merge base
690 * between A and B, A...B names that merge base.
691 *
692 * With no paths, if <something> is _not_ a commit, no -t nor -b
693 * was given, and there is a tracking branch whose name is
694 * <something> in one and only one remote, then this is a short-hand
695 * to fork local <something> from that remote tracking branch.
696 *
697 * Otherwise <something> shall not be ambiguous.
698 * - If it's *only* a reference, treat it like case (1).
699 * - If it's only a path, treat it like case (2).
700 * - else: fail.
701 *
702 */
703 if (argc) {
704 if (!strcmp(argv[0], "--")) { /* case (2) */
705 argv++;
706 argc--;
707 goto no_reference;
708 }
709
710 arg = argv[0];
711 has_dash_dash = (argc > 1) && !strcmp(argv[1], "--");
712
713 if (!strcmp(arg, "-"))
714 arg = "@{-1}";
715
716 if (get_sha1_mb(arg, rev)) {
717 if (has_dash_dash) /* case (1) */
718 die("invalid reference: %s", arg);
719 if (!patch_mode &&
720 dwim_new_local_branch &&
721 opts.track == BRANCH_TRACK_UNSPECIFIED &&
722 !opts.new_branch &&
723 !check_filename(NULL, arg) &&
724 argc == 1) {
725 const char *remote = unique_tracking_name(arg);
726 if (!remote || get_sha1(remote, rev))
727 goto no_reference;
728 opts.new_branch = arg;
729 arg = remote;
730 /* DWIMmed to create local branch */
731 }
732 else
733 goto no_reference;
734 }
735
736 /* we can't end up being in (2) anymore, eat the argument */
737 argv++;
738 argc--;
739
740 new.name = arg;
741 if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
742 setup_branch_path(&new);
743
744 if ((check_ref_format(new.path) == CHECK_REF_FORMAT_OK) &&
745 resolve_ref(new.path, rev, 1, NULL))
746 ;
747 else
748 new.path = NULL;
749 parse_commit(new.commit);
750 source_tree = new.commit->tree;
751 } else
752 source_tree = parse_tree_indirect(rev);
753
754 if (!source_tree) /* case (1): want a tree */
755 die("reference is not a tree: %s", arg);
756 if (!has_dash_dash) {/* case (3 -> 1) */
757 /*
758 * Do not complain the most common case
759 * git checkout branch
760 * even if there happen to be a file called 'branch';
761 * it would be extremely annoying.
762 */
763 if (argc)
764 verify_non_filename(NULL, arg);
765 }
766 else {
767 argv++;
768 argc--;
769 }
770 }
771
772 no_reference:
773
774 if (opts.track == BRANCH_TRACK_UNSPECIFIED)
775 opts.track = git_branch_track;
776
777 if (argc) {
778 const char **pathspec = get_pathspec(prefix, argv);
779
780 if (!pathspec)
781 die("invalid path specification");
782
783 if (patch_mode)
784 return interactive_checkout(new.name, pathspec, &opts);
785
786 /* Checkout paths */
787 if (opts.new_branch) {
788 if (argc == 1) {
789 die("git checkout: updating paths is incompatible with switching branches.\nDid you intend to checkout '%s' which can not be resolved as commit?", argv[0]);
790 } else {
791 die("git checkout: updating paths is incompatible with switching branches.");
792 }
793 }
794
795 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
796 die("git checkout: --ours/--theirs, --force and --merge are incompatible when\nchecking out of the index.");
797
798 return checkout_paths(source_tree, pathspec, &opts);
799 }
800
801 if (patch_mode)
802 return interactive_checkout(new.name, NULL, &opts);
803
804 if (opts.new_branch) {
805 struct strbuf buf = STRBUF_INIT;
806 if (strbuf_check_branch_ref(&buf, opts.new_branch))
807 die("git checkout: we do not like '%s' as a branch name.",
808 opts.new_branch);
809 if (!get_sha1(buf.buf, rev))
810 die("git checkout: branch %s already exists", opts.new_branch);
811 strbuf_release(&buf);
812 }
813
814 if (new.name && !new.commit) {
815 die("Cannot switch branch to a non-commit.");
816 }
817 if (opts.writeout_stage)
818 die("--ours/--theirs is incompatible with switching branches.");
819
820 return switch_branches(&opts, &new);
821 }