refs: make pack_refs() virtual
[git.git] / builtin / pull.c
blobd98f481d31535fd63773fd987b5a252901ca2ac0
1 /*
2 * Builtin "git pull"
4 * Based on git-pull.sh by Junio C Hamano
6 * Fetch one or more remote refs and merge it/them into the current HEAD.
7 */
8 #include "cache.h"
9 #include "builtin.h"
10 #include "parse-options.h"
11 #include "exec_cmd.h"
12 #include "run-command.h"
13 #include "sha1-array.h"
14 #include "remote.h"
15 #include "dir.h"
16 #include "refs.h"
17 #include "revision.h"
18 #include "tempfile.h"
19 #include "lockfile.h"
21 enum rebase_type {
22 REBASE_INVALID = -1,
23 REBASE_FALSE = 0,
24 REBASE_TRUE,
25 REBASE_PRESERVE,
26 REBASE_INTERACTIVE
29 /**
30 * Parses the value of --rebase. If value is a false value, returns
31 * REBASE_FALSE. If value is a true value, returns REBASE_TRUE. If value is
32 * "preserve", returns REBASE_PRESERVE. If value is a invalid value, dies with
33 * a fatal error if fatal is true, otherwise returns REBASE_INVALID.
35 static enum rebase_type parse_config_rebase(const char *key, const char *value,
36 int fatal)
38 int v = git_config_maybe_bool("pull.rebase", value);
40 if (!v)
41 return REBASE_FALSE;
42 else if (v > 0)
43 return REBASE_TRUE;
44 else if (!strcmp(value, "preserve"))
45 return REBASE_PRESERVE;
46 else if (!strcmp(value, "interactive"))
47 return REBASE_INTERACTIVE;
49 if (fatal)
50 die(_("Invalid value for %s: %s"), key, value);
51 else
52 error(_("Invalid value for %s: %s"), key, value);
54 return REBASE_INVALID;
57 /**
58 * Callback for --rebase, which parses arg with parse_config_rebase().
60 static int parse_opt_rebase(const struct option *opt, const char *arg, int unset)
62 enum rebase_type *value = opt->value;
64 if (arg)
65 *value = parse_config_rebase("--rebase", arg, 0);
66 else
67 *value = unset ? REBASE_FALSE : REBASE_TRUE;
68 return *value == REBASE_INVALID ? -1 : 0;
71 static const char * const pull_usage[] = {
72 N_("git pull [<options>] [<repository> [<refspec>...]]"),
73 NULL
76 /* Shared options */
77 static int opt_verbosity;
78 static char *opt_progress;
80 /* Options passed to git-merge or git-rebase */
81 static enum rebase_type opt_rebase = -1;
82 static char *opt_diffstat;
83 static char *opt_log;
84 static char *opt_squash;
85 static char *opt_commit;
86 static char *opt_edit;
87 static char *opt_ff;
88 static char *opt_verify_signatures;
89 static int opt_autostash = -1;
90 static int config_autostash;
91 static struct argv_array opt_strategies = ARGV_ARRAY_INIT;
92 static struct argv_array opt_strategy_opts = ARGV_ARRAY_INIT;
93 static char *opt_gpg_sign;
95 /* Options passed to git-fetch */
96 static char *opt_all;
97 static char *opt_append;
98 static char *opt_upload_pack;
99 static int opt_force;
100 static char *opt_tags;
101 static char *opt_prune;
102 static char *opt_recurse_submodules;
103 static char *max_children;
104 static int opt_dry_run;
105 static char *opt_keep;
106 static char *opt_depth;
107 static char *opt_unshallow;
108 static char *opt_update_shallow;
109 static char *opt_refmap;
111 static struct option pull_options[] = {
112 /* Shared options */
113 OPT__VERBOSITY(&opt_verbosity),
114 OPT_PASSTHRU(0, "progress", &opt_progress, NULL,
115 N_("force progress reporting"),
116 PARSE_OPT_NOARG),
118 /* Options passed to git-merge or git-rebase */
119 OPT_GROUP(N_("Options related to merging")),
120 { OPTION_CALLBACK, 'r', "rebase", &opt_rebase,
121 "false|true|preserve|interactive",
122 N_("incorporate changes by rebasing rather than merging"),
123 PARSE_OPT_OPTARG, parse_opt_rebase },
124 OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL,
125 N_("do not show a diffstat at the end of the merge"),
126 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
127 OPT_PASSTHRU(0, "stat", &opt_diffstat, NULL,
128 N_("show a diffstat at the end of the merge"),
129 PARSE_OPT_NOARG),
130 OPT_PASSTHRU(0, "summary", &opt_diffstat, NULL,
131 N_("(synonym to --stat)"),
132 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN),
133 OPT_PASSTHRU(0, "log", &opt_log, N_("n"),
134 N_("add (at most <n>) entries from shortlog to merge commit message"),
135 PARSE_OPT_OPTARG),
136 OPT_PASSTHRU(0, "squash", &opt_squash, NULL,
137 N_("create a single commit instead of doing a merge"),
138 PARSE_OPT_NOARG),
139 OPT_PASSTHRU(0, "commit", &opt_commit, NULL,
140 N_("perform a commit if the merge succeeds (default)"),
141 PARSE_OPT_NOARG),
142 OPT_PASSTHRU(0, "edit", &opt_edit, NULL,
143 N_("edit message before committing"),
144 PARSE_OPT_NOARG),
145 OPT_PASSTHRU(0, "ff", &opt_ff, NULL,
146 N_("allow fast-forward"),
147 PARSE_OPT_NOARG),
148 OPT_PASSTHRU(0, "ff-only", &opt_ff, NULL,
149 N_("abort if fast-forward is not possible"),
150 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
151 OPT_PASSTHRU(0, "verify-signatures", &opt_verify_signatures, NULL,
152 N_("verify that the named commit has a valid GPG signature"),
153 PARSE_OPT_NOARG),
154 OPT_BOOL(0, "autostash", &opt_autostash,
155 N_("automatically stash/stash pop before and after rebase")),
156 OPT_PASSTHRU_ARGV('s', "strategy", &opt_strategies, N_("strategy"),
157 N_("merge strategy to use"),
159 OPT_PASSTHRU_ARGV('X', "strategy-option", &opt_strategy_opts,
160 N_("option=value"),
161 N_("option for selected merge strategy"),
163 OPT_PASSTHRU('S', "gpg-sign", &opt_gpg_sign, N_("key-id"),
164 N_("GPG sign commit"),
165 PARSE_OPT_OPTARG),
167 /* Options passed to git-fetch */
168 OPT_GROUP(N_("Options related to fetching")),
169 OPT_PASSTHRU(0, "all", &opt_all, NULL,
170 N_("fetch from all remotes"),
171 PARSE_OPT_NOARG),
172 OPT_PASSTHRU('a', "append", &opt_append, NULL,
173 N_("append to .git/FETCH_HEAD instead of overwriting"),
174 PARSE_OPT_NOARG),
175 OPT_PASSTHRU(0, "upload-pack", &opt_upload_pack, N_("path"),
176 N_("path to upload pack on remote end"),
178 OPT__FORCE(&opt_force, N_("force overwrite of local branch")),
179 OPT_PASSTHRU('t', "tags", &opt_tags, NULL,
180 N_("fetch all tags and associated objects"),
181 PARSE_OPT_NOARG),
182 OPT_PASSTHRU('p', "prune", &opt_prune, NULL,
183 N_("prune remote-tracking branches no longer on remote"),
184 PARSE_OPT_NOARG),
185 OPT_PASSTHRU(0, "recurse-submodules", &opt_recurse_submodules,
186 N_("on-demand"),
187 N_("control recursive fetching of submodules"),
188 PARSE_OPT_OPTARG),
189 OPT_PASSTHRU('j', "jobs", &max_children, N_("n"),
190 N_("number of submodules pulled in parallel"),
191 PARSE_OPT_OPTARG),
192 OPT_BOOL(0, "dry-run", &opt_dry_run,
193 N_("dry run")),
194 OPT_PASSTHRU('k', "keep", &opt_keep, NULL,
195 N_("keep downloaded pack"),
196 PARSE_OPT_NOARG),
197 OPT_PASSTHRU(0, "depth", &opt_depth, N_("depth"),
198 N_("deepen history of shallow clone"),
200 OPT_PASSTHRU(0, "unshallow", &opt_unshallow, NULL,
201 N_("convert to a complete repository"),
202 PARSE_OPT_NONEG | PARSE_OPT_NOARG),
203 OPT_PASSTHRU(0, "update-shallow", &opt_update_shallow, NULL,
204 N_("accept refs that update .git/shallow"),
205 PARSE_OPT_NOARG),
206 OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"),
207 N_("specify fetch refmap"),
208 PARSE_OPT_NONEG),
210 OPT_END()
214 * Pushes "-q" or "-v" switches into arr to match the opt_verbosity level.
216 static void argv_push_verbosity(struct argv_array *arr)
218 int verbosity;
220 for (verbosity = opt_verbosity; verbosity > 0; verbosity--)
221 argv_array_push(arr, "-v");
223 for (verbosity = opt_verbosity; verbosity < 0; verbosity++)
224 argv_array_push(arr, "-q");
228 * Pushes "-f" switches into arr to match the opt_force level.
230 static void argv_push_force(struct argv_array *arr)
232 int force = opt_force;
233 while (force-- > 0)
234 argv_array_push(arr, "-f");
238 * Sets the GIT_REFLOG_ACTION environment variable to the concatenation of argv
240 static void set_reflog_message(int argc, const char **argv)
242 int i;
243 struct strbuf msg = STRBUF_INIT;
245 for (i = 0; i < argc; i++) {
246 if (i)
247 strbuf_addch(&msg, ' ');
248 strbuf_addstr(&msg, argv[i]);
251 setenv("GIT_REFLOG_ACTION", msg.buf, 0);
253 strbuf_release(&msg);
257 * If pull.ff is unset, returns NULL. If pull.ff is "true", returns "--ff". If
258 * pull.ff is "false", returns "--no-ff". If pull.ff is "only", returns
259 * "--ff-only". Otherwise, if pull.ff is set to an invalid value, die with an
260 * error.
262 static const char *config_get_ff(void)
264 const char *value;
266 if (git_config_get_value("pull.ff", &value))
267 return NULL;
269 switch (git_config_maybe_bool("pull.ff", value)) {
270 case 0:
271 return "--no-ff";
272 case 1:
273 return "--ff";
276 if (!strcmp(value, "only"))
277 return "--ff-only";
279 die(_("Invalid value for pull.ff: %s"), value);
283 * Returns the default configured value for --rebase. It first looks for the
284 * value of "branch.$curr_branch.rebase", where $curr_branch is the current
285 * branch, and if HEAD is detached or the configuration key does not exist,
286 * looks for the value of "pull.rebase". If both configuration keys do not
287 * exist, returns REBASE_FALSE.
289 static enum rebase_type config_get_rebase(void)
291 struct branch *curr_branch = branch_get("HEAD");
292 const char *value;
294 if (curr_branch) {
295 char *key = xstrfmt("branch.%s.rebase", curr_branch->name);
297 if (!git_config_get_value(key, &value)) {
298 enum rebase_type ret = parse_config_rebase(key, value, 1);
299 free(key);
300 return ret;
303 free(key);
306 if (!git_config_get_value("pull.rebase", &value))
307 return parse_config_rebase("pull.rebase", value, 1);
309 return REBASE_FALSE;
313 * Read config variables.
315 static int git_pull_config(const char *var, const char *value, void *cb)
317 if (!strcmp(var, "rebase.autostash")) {
318 config_autostash = git_config_bool(var, value);
319 return 0;
321 return git_default_config(var, value, cb);
325 * Returns 1 if there are unstaged changes, 0 otherwise.
327 static int has_unstaged_changes(const char *prefix)
329 struct rev_info rev_info;
330 int result;
332 init_revisions(&rev_info, prefix);
333 DIFF_OPT_SET(&rev_info.diffopt, IGNORE_SUBMODULES);
334 DIFF_OPT_SET(&rev_info.diffopt, QUICK);
335 diff_setup_done(&rev_info.diffopt);
336 result = run_diff_files(&rev_info, 0);
337 return diff_result_code(&rev_info.diffopt, result);
341 * Returns 1 if there are uncommitted changes, 0 otherwise.
343 static int has_uncommitted_changes(const char *prefix)
345 struct rev_info rev_info;
346 int result;
348 if (is_cache_unborn())
349 return 0;
351 init_revisions(&rev_info, prefix);
352 DIFF_OPT_SET(&rev_info.diffopt, IGNORE_SUBMODULES);
353 DIFF_OPT_SET(&rev_info.diffopt, QUICK);
354 add_head_to_pending(&rev_info);
355 diff_setup_done(&rev_info.diffopt);
356 result = run_diff_index(&rev_info, 1);
357 return diff_result_code(&rev_info.diffopt, result);
361 * If the work tree has unstaged or uncommitted changes, dies with the
362 * appropriate message.
364 static void die_on_unclean_work_tree(const char *prefix)
366 struct lock_file *lock_file = xcalloc(1, sizeof(*lock_file));
367 int do_die = 0;
369 hold_locked_index(lock_file, 0);
370 refresh_cache(REFRESH_QUIET);
371 update_index_if_able(&the_index, lock_file);
372 rollback_lock_file(lock_file);
374 if (has_unstaged_changes(prefix)) {
375 error(_("Cannot pull with rebase: You have unstaged changes."));
376 do_die = 1;
379 if (has_uncommitted_changes(prefix)) {
380 if (do_die)
381 error(_("Additionally, your index contains uncommitted changes."));
382 else
383 error(_("Cannot pull with rebase: Your index contains uncommitted changes."));
384 do_die = 1;
387 if (do_die)
388 exit(1);
392 * Appends merge candidates from FETCH_HEAD that are not marked not-for-merge
393 * into merge_heads.
395 static void get_merge_heads(struct sha1_array *merge_heads)
397 const char *filename = git_path("FETCH_HEAD");
398 FILE *fp;
399 struct strbuf sb = STRBUF_INIT;
400 unsigned char sha1[GIT_SHA1_RAWSZ];
402 if (!(fp = fopen(filename, "r")))
403 die_errno(_("could not open '%s' for reading"), filename);
404 while (strbuf_getline_lf(&sb, fp) != EOF) {
405 if (get_sha1_hex(sb.buf, sha1))
406 continue; /* invalid line: does not start with SHA1 */
407 if (starts_with(sb.buf + GIT_SHA1_HEXSZ, "\tnot-for-merge\t"))
408 continue; /* ref is not-for-merge */
409 sha1_array_append(merge_heads, sha1);
411 fclose(fp);
412 strbuf_release(&sb);
416 * Used by die_no_merge_candidates() as a for_each_remote() callback to
417 * retrieve the name of the remote if the repository only has one remote.
419 static int get_only_remote(struct remote *remote, void *cb_data)
421 const char **remote_name = cb_data;
423 if (*remote_name)
424 return -1;
426 *remote_name = remote->name;
427 return 0;
431 * Dies with the appropriate reason for why there are no merge candidates:
433 * 1. We fetched from a specific remote, and a refspec was given, but it ended
434 * up not fetching anything. This is usually because the user provided a
435 * wildcard refspec which had no matches on the remote end.
437 * 2. We fetched from a non-default remote, but didn't specify a branch to
438 * merge. We can't use the configured one because it applies to the default
439 * remote, thus the user must specify the branches to merge.
441 * 3. We fetched from the branch's or repo's default remote, but:
443 * a. We are not on a branch, so there will never be a configured branch to
444 * merge with.
446 * b. We are on a branch, but there is no configured branch to merge with.
448 * 4. We fetched from the branch's or repo's default remote, but the configured
449 * branch to merge didn't get fetched. (Either it doesn't exist, or wasn't
450 * part of the configured fetch refspec.)
452 static void NORETURN die_no_merge_candidates(const char *repo, const char **refspecs)
454 struct branch *curr_branch = branch_get("HEAD");
455 const char *remote = curr_branch ? curr_branch->remote_name : NULL;
457 if (*refspecs) {
458 if (opt_rebase)
459 fprintf_ln(stderr, _("There is no candidate for rebasing against among the refs that you just fetched."));
460 else
461 fprintf_ln(stderr, _("There are no candidates for merging among the refs that you just fetched."));
462 fprintf_ln(stderr, _("Generally this means that you provided a wildcard refspec which had no\n"
463 "matches on the remote end."));
464 } else if (repo && curr_branch && (!remote || strcmp(repo, remote))) {
465 fprintf_ln(stderr, _("You asked to pull from the remote '%s', but did not specify\n"
466 "a branch. Because this is not the default configured remote\n"
467 "for your current branch, you must specify a branch on the command line."),
468 repo);
469 } else if (!curr_branch) {
470 fprintf_ln(stderr, _("You are not currently on a branch."));
471 if (opt_rebase)
472 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
473 else
474 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
475 fprintf_ln(stderr, _("See git-pull(1) for details."));
476 fprintf(stderr, "\n");
477 fprintf_ln(stderr, " git pull <remote> <branch>");
478 fprintf(stderr, "\n");
479 } else if (!curr_branch->merge_nr) {
480 const char *remote_name = NULL;
482 if (for_each_remote(get_only_remote, &remote_name) || !remote_name)
483 remote_name = "<remote>";
485 fprintf_ln(stderr, _("There is no tracking information for the current branch."));
486 if (opt_rebase)
487 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
488 else
489 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
490 fprintf_ln(stderr, _("See git-pull(1) for details."));
491 fprintf(stderr, "\n");
492 fprintf_ln(stderr, " git pull <remote> <branch>");
493 fprintf(stderr, "\n");
494 fprintf_ln(stderr, _("If you wish to set tracking information for this branch you can do so with:\n"
495 "\n"
496 " git branch --set-upstream-to=%s/<branch> %s\n"),
497 remote_name, curr_branch->name);
498 } else
499 fprintf_ln(stderr, _("Your configuration specifies to merge with the ref '%s'\n"
500 "from the remote, but no such ref was fetched."),
501 *curr_branch->merge_name);
502 exit(1);
506 * Parses argv into [<repo> [<refspecs>...]], returning their values in `repo`
507 * as a string and `refspecs` as a null-terminated array of strings. If `repo`
508 * is not provided in argv, it is set to NULL.
510 static void parse_repo_refspecs(int argc, const char **argv, const char **repo,
511 const char ***refspecs)
513 if (argc > 0) {
514 *repo = *argv++;
515 argc--;
516 } else
517 *repo = NULL;
518 *refspecs = argv;
522 * Runs git-fetch, returning its exit status. `repo` and `refspecs` are the
523 * repository and refspecs to fetch, or NULL if they are not provided.
525 static int run_fetch(const char *repo, const char **refspecs)
527 struct argv_array args = ARGV_ARRAY_INIT;
528 int ret;
530 argv_array_pushl(&args, "fetch", "--update-head-ok", NULL);
532 /* Shared options */
533 argv_push_verbosity(&args);
534 if (opt_progress)
535 argv_array_push(&args, opt_progress);
537 /* Options passed to git-fetch */
538 if (opt_all)
539 argv_array_push(&args, opt_all);
540 if (opt_append)
541 argv_array_push(&args, opt_append);
542 if (opt_upload_pack)
543 argv_array_push(&args, opt_upload_pack);
544 argv_push_force(&args);
545 if (opt_tags)
546 argv_array_push(&args, opt_tags);
547 if (opt_prune)
548 argv_array_push(&args, opt_prune);
549 if (opt_recurse_submodules)
550 argv_array_push(&args, opt_recurse_submodules);
551 if (max_children)
552 argv_array_push(&args, max_children);
553 if (opt_dry_run)
554 argv_array_push(&args, "--dry-run");
555 if (opt_keep)
556 argv_array_push(&args, opt_keep);
557 if (opt_depth)
558 argv_array_push(&args, opt_depth);
559 if (opt_unshallow)
560 argv_array_push(&args, opt_unshallow);
561 if (opt_update_shallow)
562 argv_array_push(&args, opt_update_shallow);
563 if (opt_refmap)
564 argv_array_push(&args, opt_refmap);
566 if (repo) {
567 argv_array_push(&args, repo);
568 argv_array_pushv(&args, refspecs);
569 } else if (*refspecs)
570 die("BUG: refspecs without repo?");
571 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
572 argv_array_clear(&args);
573 return ret;
577 * "Pulls into void" by branching off merge_head.
579 static int pull_into_void(const unsigned char *merge_head,
580 const unsigned char *curr_head)
583 * Two-way merge: we treat the index as based on an empty tree,
584 * and try to fast-forward to HEAD. This ensures we will not lose
585 * index/worktree changes that the user already made on the unborn
586 * branch.
588 if (checkout_fast_forward(EMPTY_TREE_SHA1_BIN, merge_head, 0))
589 return 1;
591 if (update_ref("initial pull", "HEAD", merge_head, curr_head, 0, UPDATE_REFS_DIE_ON_ERR))
592 return 1;
594 return 0;
598 * Runs git-merge, returning its exit status.
600 static int run_merge(void)
602 int ret;
603 struct argv_array args = ARGV_ARRAY_INIT;
605 argv_array_pushl(&args, "merge", NULL);
607 /* Shared options */
608 argv_push_verbosity(&args);
609 if (opt_progress)
610 argv_array_push(&args, opt_progress);
612 /* Options passed to git-merge */
613 if (opt_diffstat)
614 argv_array_push(&args, opt_diffstat);
615 if (opt_log)
616 argv_array_push(&args, opt_log);
617 if (opt_squash)
618 argv_array_push(&args, opt_squash);
619 if (opt_commit)
620 argv_array_push(&args, opt_commit);
621 if (opt_edit)
622 argv_array_push(&args, opt_edit);
623 if (opt_ff)
624 argv_array_push(&args, opt_ff);
625 if (opt_verify_signatures)
626 argv_array_push(&args, opt_verify_signatures);
627 argv_array_pushv(&args, opt_strategies.argv);
628 argv_array_pushv(&args, opt_strategy_opts.argv);
629 if (opt_gpg_sign)
630 argv_array_push(&args, opt_gpg_sign);
632 argv_array_push(&args, "FETCH_HEAD");
633 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
634 argv_array_clear(&args);
635 return ret;
639 * Returns remote's upstream branch for the current branch. If remote is NULL,
640 * the current branch's configured default remote is used. Returns NULL if
641 * `remote` does not name a valid remote, HEAD does not point to a branch,
642 * remote is not the branch's configured remote or the branch does not have any
643 * configured upstream branch.
645 static const char *get_upstream_branch(const char *remote)
647 struct remote *rm;
648 struct branch *curr_branch;
649 const char *curr_branch_remote;
651 rm = remote_get(remote);
652 if (!rm)
653 return NULL;
655 curr_branch = branch_get("HEAD");
656 if (!curr_branch)
657 return NULL;
659 curr_branch_remote = remote_for_branch(curr_branch, NULL);
660 assert(curr_branch_remote);
662 if (strcmp(curr_branch_remote, rm->name))
663 return NULL;
665 return branch_get_upstream(curr_branch, NULL);
669 * Derives the remote tracking branch from the remote and refspec.
671 * FIXME: The current implementation assumes the default mapping of
672 * refs/heads/<branch_name> to refs/remotes/<remote_name>/<branch_name>.
674 static const char *get_tracking_branch(const char *remote, const char *refspec)
676 struct refspec *spec;
677 const char *spec_src;
678 const char *merge_branch;
680 spec = parse_fetch_refspec(1, &refspec);
681 spec_src = spec->src;
682 if (!*spec_src || !strcmp(spec_src, "HEAD"))
683 spec_src = "HEAD";
684 else if (skip_prefix(spec_src, "heads/", &spec_src))
686 else if (skip_prefix(spec_src, "refs/heads/", &spec_src))
688 else if (starts_with(spec_src, "refs/") ||
689 starts_with(spec_src, "tags/") ||
690 starts_with(spec_src, "remotes/"))
691 spec_src = "";
693 if (*spec_src) {
694 if (!strcmp(remote, "."))
695 merge_branch = mkpath("refs/heads/%s", spec_src);
696 else
697 merge_branch = mkpath("refs/remotes/%s/%s", remote, spec_src);
698 } else
699 merge_branch = NULL;
701 free_refspec(1, spec);
702 return merge_branch;
706 * Given the repo and refspecs, sets fork_point to the point at which the
707 * current branch forked from its remote tracking branch. Returns 0 on success,
708 * -1 on failure.
710 static int get_rebase_fork_point(unsigned char *fork_point, const char *repo,
711 const char *refspec)
713 int ret;
714 struct branch *curr_branch;
715 const char *remote_branch;
716 struct child_process cp = CHILD_PROCESS_INIT;
717 struct strbuf sb = STRBUF_INIT;
719 curr_branch = branch_get("HEAD");
720 if (!curr_branch)
721 return -1;
723 if (refspec)
724 remote_branch = get_tracking_branch(repo, refspec);
725 else
726 remote_branch = get_upstream_branch(repo);
728 if (!remote_branch)
729 return -1;
731 argv_array_pushl(&cp.args, "merge-base", "--fork-point",
732 remote_branch, curr_branch->name, NULL);
733 cp.no_stdin = 1;
734 cp.no_stderr = 1;
735 cp.git_cmd = 1;
737 ret = capture_command(&cp, &sb, GIT_SHA1_HEXSZ);
738 if (ret)
739 goto cleanup;
741 ret = get_sha1_hex(sb.buf, fork_point);
742 if (ret)
743 goto cleanup;
745 cleanup:
746 strbuf_release(&sb);
747 return ret ? -1 : 0;
751 * Sets merge_base to the octopus merge base of curr_head, merge_head and
752 * fork_point. Returns 0 if a merge base is found, 1 otherwise.
754 static int get_octopus_merge_base(unsigned char *merge_base,
755 const unsigned char *curr_head,
756 const unsigned char *merge_head,
757 const unsigned char *fork_point)
759 struct commit_list *revs = NULL, *result;
761 commit_list_insert(lookup_commit_reference(curr_head), &revs);
762 commit_list_insert(lookup_commit_reference(merge_head), &revs);
763 if (!is_null_sha1(fork_point))
764 commit_list_insert(lookup_commit_reference(fork_point), &revs);
766 result = reduce_heads(get_octopus_merge_bases(revs));
767 free_commit_list(revs);
768 if (!result)
769 return 1;
771 hashcpy(merge_base, result->item->object.oid.hash);
772 return 0;
776 * Given the current HEAD SHA1, the merge head returned from git-fetch and the
777 * fork point calculated by get_rebase_fork_point(), runs git-rebase with the
778 * appropriate arguments and returns its exit status.
780 static int run_rebase(const unsigned char *curr_head,
781 const unsigned char *merge_head,
782 const unsigned char *fork_point)
784 int ret;
785 unsigned char oct_merge_base[GIT_SHA1_RAWSZ];
786 struct argv_array args = ARGV_ARRAY_INIT;
788 if (!get_octopus_merge_base(oct_merge_base, curr_head, merge_head, fork_point))
789 if (!is_null_sha1(fork_point) && !hashcmp(oct_merge_base, fork_point))
790 fork_point = NULL;
792 argv_array_push(&args, "rebase");
794 /* Shared options */
795 argv_push_verbosity(&args);
797 /* Options passed to git-rebase */
798 if (opt_rebase == REBASE_PRESERVE)
799 argv_array_push(&args, "--preserve-merges");
800 else if (opt_rebase == REBASE_INTERACTIVE)
801 argv_array_push(&args, "--interactive");
802 if (opt_diffstat)
803 argv_array_push(&args, opt_diffstat);
804 argv_array_pushv(&args, opt_strategies.argv);
805 argv_array_pushv(&args, opt_strategy_opts.argv);
806 if (opt_gpg_sign)
807 argv_array_push(&args, opt_gpg_sign);
808 if (opt_autostash == 0)
809 argv_array_push(&args, "--no-autostash");
810 else if (opt_autostash == 1)
811 argv_array_push(&args, "--autostash");
813 argv_array_push(&args, "--onto");
814 argv_array_push(&args, sha1_to_hex(merge_head));
816 if (fork_point && !is_null_sha1(fork_point))
817 argv_array_push(&args, sha1_to_hex(fork_point));
818 else
819 argv_array_push(&args, sha1_to_hex(merge_head));
821 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
822 argv_array_clear(&args);
823 return ret;
826 int cmd_pull(int argc, const char **argv, const char *prefix)
828 const char *repo, **refspecs;
829 struct sha1_array merge_heads = SHA1_ARRAY_INIT;
830 unsigned char orig_head[GIT_SHA1_RAWSZ], curr_head[GIT_SHA1_RAWSZ];
831 unsigned char rebase_fork_point[GIT_SHA1_RAWSZ];
833 if (!getenv("GIT_REFLOG_ACTION"))
834 set_reflog_message(argc, argv);
836 argc = parse_options(argc, argv, prefix, pull_options, pull_usage, 0);
838 parse_repo_refspecs(argc, argv, &repo, &refspecs);
840 if (!opt_ff)
841 opt_ff = xstrdup_or_null(config_get_ff());
843 if (opt_rebase < 0)
844 opt_rebase = config_get_rebase();
846 git_config(git_pull_config, NULL);
848 if (read_cache_unmerged())
849 die_resolve_conflict("Pull");
851 if (file_exists(git_path("MERGE_HEAD")))
852 die_conclude_merge();
854 if (get_sha1("HEAD", orig_head))
855 hashclr(orig_head);
857 if (!opt_rebase && opt_autostash != -1)
858 die(_("--[no-]autostash option is only valid with --rebase."));
860 if (opt_rebase) {
861 int autostash = config_autostash;
862 if (opt_autostash != -1)
863 autostash = opt_autostash;
865 if (is_null_sha1(orig_head) && !is_cache_unborn())
866 die(_("Updating an unborn branch with changes added to the index."));
868 if (!autostash)
869 die_on_unclean_work_tree(prefix);
871 if (get_rebase_fork_point(rebase_fork_point, repo, *refspecs))
872 hashclr(rebase_fork_point);
875 if (run_fetch(repo, refspecs))
876 return 1;
878 if (opt_dry_run)
879 return 0;
881 if (get_sha1("HEAD", curr_head))
882 hashclr(curr_head);
884 if (!is_null_sha1(orig_head) && !is_null_sha1(curr_head) &&
885 hashcmp(orig_head, curr_head)) {
887 * The fetch involved updating the current branch.
889 * The working tree and the index file are still based on
890 * orig_head commit, but we are merging into curr_head.
891 * Update the working tree to match curr_head.
894 warning(_("fetch updated the current branch head.\n"
895 "fast-forwarding your working tree from\n"
896 "commit %s."), sha1_to_hex(orig_head));
898 if (checkout_fast_forward(orig_head, curr_head, 0))
899 die(_("Cannot fast-forward your working tree.\n"
900 "After making sure that you saved anything precious from\n"
901 "$ git diff %s\n"
902 "output, run\n"
903 "$ git reset --hard\n"
904 "to recover."), sha1_to_hex(orig_head));
907 get_merge_heads(&merge_heads);
909 if (!merge_heads.nr)
910 die_no_merge_candidates(repo, refspecs);
912 if (is_null_sha1(orig_head)) {
913 if (merge_heads.nr > 1)
914 die(_("Cannot merge multiple branches into empty head."));
915 return pull_into_void(*merge_heads.sha1, curr_head);
916 } else if (opt_rebase) {
917 if (merge_heads.nr > 1)
918 die(_("Cannot rebase onto multiple branches."));
919 return run_rebase(curr_head, *merge_heads.sha1, rebase_fork_point);
920 } else
921 return run_merge();