color: add support for 12-bit RGB colors
[alt-git.git] / builtin / pull.c
blob72cbb76d520718cfc2f23093dd5ef76ea2d682bf
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 #define USE_THE_INDEX_VARIABLE
9 #include "builtin.h"
10 #include "advice.h"
11 #include "config.h"
12 #include "gettext.h"
13 #include "hex.h"
14 #include "merge.h"
15 #include "object-name.h"
16 #include "parse-options.h"
17 #include "run-command.h"
18 #include "oid-array.h"
19 #include "remote.h"
20 #include "dir.h"
21 #include "path.h"
22 #include "read-cache-ll.h"
23 #include "rebase.h"
24 #include "refs.h"
25 #include "refspec.h"
26 #include "submodule.h"
27 #include "submodule-config.h"
28 #include "wt-status.h"
29 #include "commit-reach.h"
30 #include "sequencer.h"
32 /**
33 * Parses the value of --rebase. If value is a false value, returns
34 * REBASE_FALSE. If value is a true value, returns REBASE_TRUE. If value is
35 * "merges", returns REBASE_MERGES. If value is a invalid value, dies with
36 * a fatal error if fatal is true, otherwise returns REBASE_INVALID.
38 static enum rebase_type parse_config_rebase(const char *key, const char *value,
39 int fatal)
41 enum rebase_type v = rebase_parse_value(value);
42 if (v != REBASE_INVALID)
43 return v;
45 if (fatal)
46 die(_("invalid value for '%s': '%s'"), key, value);
47 else
48 error(_("invalid value for '%s': '%s'"), key, value);
50 return REBASE_INVALID;
53 /**
54 * Callback for --rebase, which parses arg with parse_config_rebase().
56 static int parse_opt_rebase(const struct option *opt, const char *arg, int unset)
58 enum rebase_type *value = opt->value;
60 if (arg)
61 *value = parse_config_rebase("--rebase", arg, 0);
62 else
63 *value = unset ? REBASE_FALSE : REBASE_TRUE;
64 return *value == REBASE_INVALID ? -1 : 0;
67 static const char * const pull_usage[] = {
68 N_("git pull [<options>] [<repository> [<refspec>...]]"),
69 NULL
72 /* Shared options */
73 static int opt_verbosity;
74 static char *opt_progress;
75 static int recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
76 static int recurse_submodules_cli = RECURSE_SUBMODULES_DEFAULT;
78 /* Options passed to git-merge or git-rebase */
79 static enum rebase_type opt_rebase = -1;
80 static char *opt_diffstat;
81 static char *opt_log;
82 static char *opt_signoff;
83 static char *opt_squash;
84 static char *opt_commit;
85 static char *opt_edit;
86 static char *cleanup_arg;
87 static char *opt_ff;
88 static char *opt_verify_signatures;
89 static char *opt_verify;
90 static int opt_autostash = -1;
91 static int config_autostash;
92 static int check_trust_level = 1;
93 static struct strvec opt_strategies = STRVEC_INIT;
94 static struct strvec opt_strategy_opts = STRVEC_INIT;
95 static char *opt_gpg_sign;
96 static int opt_allow_unrelated_histories;
98 /* Options passed to git-fetch */
99 static char *opt_all;
100 static char *opt_append;
101 static char *opt_upload_pack;
102 static int opt_force;
103 static char *opt_tags;
104 static char *opt_prune;
105 static char *max_children;
106 static int opt_dry_run;
107 static char *opt_keep;
108 static char *opt_depth;
109 static char *opt_unshallow;
110 static char *opt_update_shallow;
111 static char *opt_refmap;
112 static char *opt_ipv4;
113 static char *opt_ipv6;
114 static int opt_show_forced_updates = -1;
115 static char *set_upstream;
116 static struct strvec opt_fetch = STRVEC_INIT;
118 static struct option pull_options[] = {
119 /* Shared options */
120 OPT__VERBOSITY(&opt_verbosity),
121 OPT_PASSTHRU(0, "progress", &opt_progress, NULL,
122 N_("force progress reporting"),
123 PARSE_OPT_NOARG),
124 OPT_CALLBACK_F(0, "recurse-submodules",
125 &recurse_submodules_cli, N_("on-demand"),
126 N_("control for recursive fetching of submodules"),
127 PARSE_OPT_OPTARG, option_fetch_parse_recurse_submodules),
129 /* Options passed to git-merge or git-rebase */
130 OPT_GROUP(N_("Options related to merging")),
131 OPT_CALLBACK_F('r', "rebase", &opt_rebase,
132 "(false|true|merges|interactive)",
133 N_("incorporate changes by rebasing rather than merging"),
134 PARSE_OPT_OPTARG, parse_opt_rebase),
135 OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL,
136 N_("do not show a diffstat at the end of the merge"),
137 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
138 OPT_PASSTHRU(0, "stat", &opt_diffstat, NULL,
139 N_("show a diffstat at the end of the merge"),
140 PARSE_OPT_NOARG),
141 OPT_PASSTHRU(0, "summary", &opt_diffstat, NULL,
142 N_("(synonym to --stat)"),
143 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN),
144 OPT_PASSTHRU(0, "log", &opt_log, N_("n"),
145 N_("add (at most <n>) entries from shortlog to merge commit message"),
146 PARSE_OPT_OPTARG),
147 OPT_PASSTHRU(0, "signoff", &opt_signoff, NULL,
148 N_("add a Signed-off-by trailer"),
149 PARSE_OPT_OPTARG),
150 OPT_PASSTHRU(0, "squash", &opt_squash, NULL,
151 N_("create a single commit instead of doing a merge"),
152 PARSE_OPT_NOARG),
153 OPT_PASSTHRU(0, "commit", &opt_commit, NULL,
154 N_("perform a commit if the merge succeeds (default)"),
155 PARSE_OPT_NOARG),
156 OPT_PASSTHRU(0, "edit", &opt_edit, NULL,
157 N_("edit message before committing"),
158 PARSE_OPT_NOARG),
159 OPT_CLEANUP(&cleanup_arg),
160 OPT_PASSTHRU(0, "ff", &opt_ff, NULL,
161 N_("allow fast-forward"),
162 PARSE_OPT_NOARG),
163 OPT_PASSTHRU(0, "ff-only", &opt_ff, NULL,
164 N_("abort if fast-forward is not possible"),
165 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
166 OPT_PASSTHRU(0, "verify", &opt_verify, NULL,
167 N_("control use of pre-merge-commit and commit-msg hooks"),
168 PARSE_OPT_NOARG),
169 OPT_PASSTHRU(0, "verify-signatures", &opt_verify_signatures, NULL,
170 N_("verify that the named commit has a valid GPG signature"),
171 PARSE_OPT_NOARG),
172 OPT_BOOL(0, "autostash", &opt_autostash,
173 N_("automatically stash/stash pop before and after")),
174 OPT_PASSTHRU_ARGV('s', "strategy", &opt_strategies, N_("strategy"),
175 N_("merge strategy to use"),
177 OPT_PASSTHRU_ARGV('X', "strategy-option", &opt_strategy_opts,
178 N_("option=value"),
179 N_("option for selected merge strategy"),
181 OPT_PASSTHRU('S', "gpg-sign", &opt_gpg_sign, N_("key-id"),
182 N_("GPG sign commit"),
183 PARSE_OPT_OPTARG),
184 OPT_SET_INT(0, "allow-unrelated-histories",
185 &opt_allow_unrelated_histories,
186 N_("allow merging unrelated histories"), 1),
188 /* Options passed to git-fetch */
189 OPT_GROUP(N_("Options related to fetching")),
190 OPT_PASSTHRU(0, "all", &opt_all, NULL,
191 N_("fetch from all remotes"),
192 PARSE_OPT_NOARG),
193 OPT_PASSTHRU('a', "append", &opt_append, NULL,
194 N_("append to .git/FETCH_HEAD instead of overwriting"),
195 PARSE_OPT_NOARG),
196 OPT_PASSTHRU(0, "upload-pack", &opt_upload_pack, N_("path"),
197 N_("path to upload pack on remote end"),
199 OPT__FORCE(&opt_force, N_("force overwrite of local branch"), 0),
200 OPT_PASSTHRU('t', "tags", &opt_tags, NULL,
201 N_("fetch all tags and associated objects"),
202 PARSE_OPT_NOARG),
203 OPT_PASSTHRU('p', "prune", &opt_prune, NULL,
204 N_("prune remote-tracking branches no longer on remote"),
205 PARSE_OPT_NOARG),
206 OPT_PASSTHRU('j', "jobs", &max_children, N_("n"),
207 N_("number of submodules pulled in parallel"),
208 PARSE_OPT_OPTARG),
209 OPT_BOOL(0, "dry-run", &opt_dry_run,
210 N_("dry run")),
211 OPT_PASSTHRU('k', "keep", &opt_keep, NULL,
212 N_("keep downloaded pack"),
213 PARSE_OPT_NOARG),
214 OPT_PASSTHRU(0, "depth", &opt_depth, N_("depth"),
215 N_("deepen history of shallow clone"),
217 OPT_PASSTHRU_ARGV(0, "shallow-since", &opt_fetch, N_("time"),
218 N_("deepen history of shallow repository based on time"),
220 OPT_PASSTHRU_ARGV(0, "shallow-exclude", &opt_fetch, N_("revision"),
221 N_("deepen history of shallow clone, excluding rev"),
223 OPT_PASSTHRU_ARGV(0, "deepen", &opt_fetch, N_("n"),
224 N_("deepen history of shallow clone"),
226 OPT_PASSTHRU(0, "unshallow", &opt_unshallow, NULL,
227 N_("convert to a complete repository"),
228 PARSE_OPT_NONEG | PARSE_OPT_NOARG),
229 OPT_PASSTHRU(0, "update-shallow", &opt_update_shallow, NULL,
230 N_("accept refs that update .git/shallow"),
231 PARSE_OPT_NOARG),
232 OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"),
233 N_("specify fetch refmap"),
234 PARSE_OPT_NONEG),
235 OPT_PASSTHRU_ARGV('o', "server-option", &opt_fetch,
236 N_("server-specific"),
237 N_("option to transmit"),
239 OPT_PASSTHRU('4', "ipv4", &opt_ipv4, NULL,
240 N_("use IPv4 addresses only"),
241 PARSE_OPT_NOARG),
242 OPT_PASSTHRU('6', "ipv6", &opt_ipv6, NULL,
243 N_("use IPv6 addresses only"),
244 PARSE_OPT_NOARG),
245 OPT_PASSTHRU_ARGV(0, "negotiation-tip", &opt_fetch, N_("revision"),
246 N_("report that we have only objects reachable from this object"),
248 OPT_BOOL(0, "show-forced-updates", &opt_show_forced_updates,
249 N_("check for forced-updates on all updated branches")),
250 OPT_PASSTHRU(0, "set-upstream", &set_upstream, NULL,
251 N_("set upstream for git pull/fetch"),
252 PARSE_OPT_NOARG),
254 OPT_END()
258 * Pushes "-q" or "-v" switches into arr to match the opt_verbosity level.
260 static void argv_push_verbosity(struct strvec *arr)
262 int verbosity;
264 for (verbosity = opt_verbosity; verbosity > 0; verbosity--)
265 strvec_push(arr, "-v");
267 for (verbosity = opt_verbosity; verbosity < 0; verbosity++)
268 strvec_push(arr, "-q");
272 * Pushes "-f" switches into arr to match the opt_force level.
274 static void argv_push_force(struct strvec *arr)
276 int force = opt_force;
277 while (force-- > 0)
278 strvec_push(arr, "-f");
282 * Sets the GIT_REFLOG_ACTION environment variable to the concatenation of argv
284 static void set_reflog_message(int argc, const char **argv)
286 int i;
287 struct strbuf msg = STRBUF_INIT;
289 for (i = 0; i < argc; i++) {
290 if (i)
291 strbuf_addch(&msg, ' ');
292 strbuf_addstr(&msg, argv[i]);
295 setenv("GIT_REFLOG_ACTION", msg.buf, 0);
297 strbuf_release(&msg);
301 * If pull.ff is unset, returns NULL. If pull.ff is "true", returns "--ff". If
302 * pull.ff is "false", returns "--no-ff". If pull.ff is "only", returns
303 * "--ff-only". Otherwise, if pull.ff is set to an invalid value, die with an
304 * error.
306 static const char *config_get_ff(void)
308 const char *value;
310 if (git_config_get_value("pull.ff", &value))
311 return NULL;
313 switch (git_parse_maybe_bool(value)) {
314 case 0:
315 return "--no-ff";
316 case 1:
317 return "--ff";
320 if (!strcmp(value, "only"))
321 return "--ff-only";
323 die(_("invalid value for '%s': '%s'"), "pull.ff", value);
327 * Returns the default configured value for --rebase. It first looks for the
328 * value of "branch.$curr_branch.rebase", where $curr_branch is the current
329 * branch, and if HEAD is detached or the configuration key does not exist,
330 * looks for the value of "pull.rebase". If both configuration keys do not
331 * exist, returns REBASE_FALSE.
333 static enum rebase_type config_get_rebase(int *rebase_unspecified)
335 struct branch *curr_branch = branch_get("HEAD");
336 const char *value;
338 if (curr_branch) {
339 char *key = xstrfmt("branch.%s.rebase", curr_branch->name);
341 if (!git_config_get_value(key, &value)) {
342 enum rebase_type ret = parse_config_rebase(key, value, 1);
343 free(key);
344 return ret;
347 free(key);
350 if (!git_config_get_value("pull.rebase", &value))
351 return parse_config_rebase("pull.rebase", value, 1);
353 *rebase_unspecified = 1;
355 return REBASE_FALSE;
359 * Read config variables.
361 static int git_pull_config(const char *var, const char *value,
362 const struct config_context *ctx, void *cb)
364 if (!strcmp(var, "rebase.autostash")) {
365 config_autostash = git_config_bool(var, value);
366 return 0;
367 } else if (!strcmp(var, "submodule.recurse")) {
368 recurse_submodules = git_config_bool(var, value) ?
369 RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
370 return 0;
371 } else if (!strcmp(var, "gpg.mintrustlevel")) {
372 check_trust_level = 0;
375 return git_default_config(var, value, ctx, cb);
379 * Appends merge candidates from FETCH_HEAD that are not marked not-for-merge
380 * into merge_heads.
382 static void get_merge_heads(struct oid_array *merge_heads)
384 const char *filename = git_path_fetch_head(the_repository);
385 FILE *fp;
386 struct strbuf sb = STRBUF_INIT;
387 struct object_id oid;
389 fp = xfopen(filename, "r");
390 while (strbuf_getline_lf(&sb, fp) != EOF) {
391 const char *p;
392 if (parse_oid_hex(sb.buf, &oid, &p))
393 continue; /* invalid line: does not start with object ID */
394 if (starts_with(p, "\tnot-for-merge\t"))
395 continue; /* ref is not-for-merge */
396 oid_array_append(merge_heads, &oid);
398 fclose(fp);
399 strbuf_release(&sb);
403 * Used by die_no_merge_candidates() as a for_each_remote() callback to
404 * retrieve the name of the remote if the repository only has one remote.
406 static int get_only_remote(struct remote *remote, void *cb_data)
408 const char **remote_name = cb_data;
410 if (*remote_name)
411 return -1;
413 *remote_name = remote->name;
414 return 0;
418 * Dies with the appropriate reason for why there are no merge candidates:
420 * 1. We fetched from a specific remote, and a refspec was given, but it ended
421 * up not fetching anything. This is usually because the user provided a
422 * wildcard refspec which had no matches on the remote end.
424 * 2. We fetched from a non-default remote, but didn't specify a branch to
425 * merge. We can't use the configured one because it applies to the default
426 * remote, thus the user must specify the branches to merge.
428 * 3. We fetched from the branch's or repo's default remote, but:
430 * a. We are not on a branch, so there will never be a configured branch to
431 * merge with.
433 * b. We are on a branch, but there is no configured branch to merge with.
435 * 4. We fetched from the branch's or repo's default remote, but the configured
436 * branch to merge didn't get fetched. (Either it doesn't exist, or wasn't
437 * part of the configured fetch refspec.)
439 static void NORETURN die_no_merge_candidates(const char *repo, const char **refspecs)
441 struct branch *curr_branch = branch_get("HEAD");
442 const char *remote = curr_branch ? curr_branch->remote_name : NULL;
444 if (*refspecs) {
445 if (opt_rebase)
446 fprintf_ln(stderr, _("There is no candidate for rebasing against among the refs that you just fetched."));
447 else
448 fprintf_ln(stderr, _("There are no candidates for merging among the refs that you just fetched."));
449 fprintf_ln(stderr, _("Generally this means that you provided a wildcard refspec which had no\n"
450 "matches on the remote end."));
451 } else if (repo && curr_branch && (!remote || strcmp(repo, remote))) {
452 fprintf_ln(stderr, _("You asked to pull from the remote '%s', but did not specify\n"
453 "a branch. Because this is not the default configured remote\n"
454 "for your current branch, you must specify a branch on the command line."),
455 repo);
456 } else if (!curr_branch) {
457 fprintf_ln(stderr, _("You are not currently on a branch."));
458 if (opt_rebase)
459 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
460 else
461 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
462 fprintf_ln(stderr, _("See git-pull(1) for details."));
463 fprintf(stderr, "\n");
464 fprintf_ln(stderr, " git pull %s %s", _("<remote>"), _("<branch>"));
465 fprintf(stderr, "\n");
466 } else if (!curr_branch->merge_nr) {
467 const char *remote_name = NULL;
469 if (for_each_remote(get_only_remote, &remote_name) || !remote_name)
470 remote_name = _("<remote>");
472 fprintf_ln(stderr, _("There is no tracking information for the current branch."));
473 if (opt_rebase)
474 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
475 else
476 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
477 fprintf_ln(stderr, _("See git-pull(1) for details."));
478 fprintf(stderr, "\n");
479 fprintf_ln(stderr, " git pull %s %s", _("<remote>"), _("<branch>"));
480 fprintf(stderr, "\n");
481 fprintf_ln(stderr, _("If you wish to set tracking information for this branch you can do so with:"));
482 fprintf(stderr, "\n");
483 fprintf_ln(stderr, " git branch --set-upstream-to=%s/%s %s\n",
484 remote_name, _("<branch>"), curr_branch->name);
485 } else
486 fprintf_ln(stderr, _("Your configuration specifies to merge with the ref '%s'\n"
487 "from the remote, but no such ref was fetched."),
488 *curr_branch->merge_name);
489 exit(1);
493 * Parses argv into [<repo> [<refspecs>...]], returning their values in `repo`
494 * as a string and `refspecs` as a null-terminated array of strings. If `repo`
495 * is not provided in argv, it is set to NULL.
497 static void parse_repo_refspecs(int argc, const char **argv, const char **repo,
498 const char ***refspecs)
500 if (argc > 0) {
501 *repo = *argv++;
502 argc--;
503 } else
504 *repo = NULL;
505 *refspecs = argv;
509 * Runs git-fetch, returning its exit status. `repo` and `refspecs` are the
510 * repository and refspecs to fetch, or NULL if they are not provided.
512 static int run_fetch(const char *repo, const char **refspecs)
514 struct child_process cmd = CHILD_PROCESS_INIT;
516 strvec_pushl(&cmd.args, "fetch", "--update-head-ok", NULL);
518 /* Shared options */
519 argv_push_verbosity(&cmd.args);
520 if (opt_progress)
521 strvec_push(&cmd.args, opt_progress);
523 /* Options passed to git-fetch */
524 if (opt_all)
525 strvec_push(&cmd.args, opt_all);
526 if (opt_append)
527 strvec_push(&cmd.args, opt_append);
528 if (opt_upload_pack)
529 strvec_push(&cmd.args, opt_upload_pack);
530 argv_push_force(&cmd.args);
531 if (opt_tags)
532 strvec_push(&cmd.args, opt_tags);
533 if (opt_prune)
534 strvec_push(&cmd.args, opt_prune);
535 if (recurse_submodules_cli != RECURSE_SUBMODULES_DEFAULT)
536 switch (recurse_submodules_cli) {
537 case RECURSE_SUBMODULES_ON:
538 strvec_push(&cmd.args, "--recurse-submodules=on");
539 break;
540 case RECURSE_SUBMODULES_OFF:
541 strvec_push(&cmd.args, "--recurse-submodules=no");
542 break;
543 case RECURSE_SUBMODULES_ON_DEMAND:
544 strvec_push(&cmd.args, "--recurse-submodules=on-demand");
545 break;
546 default:
547 BUG("submodule recursion option not understood");
549 if (max_children)
550 strvec_push(&cmd.args, max_children);
551 if (opt_dry_run)
552 strvec_push(&cmd.args, "--dry-run");
553 if (opt_keep)
554 strvec_push(&cmd.args, opt_keep);
555 if (opt_depth)
556 strvec_push(&cmd.args, opt_depth);
557 if (opt_unshallow)
558 strvec_push(&cmd.args, opt_unshallow);
559 if (opt_update_shallow)
560 strvec_push(&cmd.args, opt_update_shallow);
561 if (opt_refmap)
562 strvec_push(&cmd.args, opt_refmap);
563 if (opt_ipv4)
564 strvec_push(&cmd.args, opt_ipv4);
565 if (opt_ipv6)
566 strvec_push(&cmd.args, opt_ipv6);
567 if (opt_show_forced_updates > 0)
568 strvec_push(&cmd.args, "--show-forced-updates");
569 else if (opt_show_forced_updates == 0)
570 strvec_push(&cmd.args, "--no-show-forced-updates");
571 if (set_upstream)
572 strvec_push(&cmd.args, set_upstream);
573 strvec_pushv(&cmd.args, opt_fetch.v);
575 if (repo) {
576 strvec_push(&cmd.args, repo);
577 strvec_pushv(&cmd.args, refspecs);
578 } else if (*refspecs)
579 BUG("refspecs without repo?");
580 cmd.git_cmd = 1;
581 cmd.close_object_store = 1;
582 return run_command(&cmd);
586 * "Pulls into void" by branching off merge_head.
588 static int pull_into_void(const struct object_id *merge_head,
589 const struct object_id *curr_head)
591 if (opt_verify_signatures) {
592 struct commit *commit;
594 commit = lookup_commit(the_repository, merge_head);
595 if (!commit)
596 die(_("unable to access commit %s"),
597 oid_to_hex(merge_head));
599 verify_merge_signature(commit, opt_verbosity,
600 check_trust_level);
604 * Two-way merge: we treat the index as based on an empty tree,
605 * and try to fast-forward to HEAD. This ensures we will not lose
606 * index/worktree changes that the user already made on the unborn
607 * branch.
609 if (checkout_fast_forward(the_repository,
610 the_hash_algo->empty_tree,
611 merge_head, 0))
612 return 1;
614 if (update_ref("initial pull", "HEAD", merge_head, curr_head, 0, UPDATE_REFS_DIE_ON_ERR))
615 return 1;
617 return 0;
620 static int rebase_submodules(void)
622 struct child_process cp = CHILD_PROCESS_INIT;
624 cp.git_cmd = 1;
625 cp.no_stdin = 1;
626 strvec_pushl(&cp.args, "submodule", "update",
627 "--recursive", "--rebase", NULL);
628 argv_push_verbosity(&cp.args);
630 return run_command(&cp);
633 static int update_submodules(void)
635 struct child_process cp = CHILD_PROCESS_INIT;
637 cp.git_cmd = 1;
638 cp.no_stdin = 1;
639 strvec_pushl(&cp.args, "submodule", "update",
640 "--recursive", "--checkout", NULL);
641 argv_push_verbosity(&cp.args);
643 return run_command(&cp);
647 * Runs git-merge, returning its exit status.
649 static int run_merge(void)
651 struct child_process cmd = CHILD_PROCESS_INIT;
653 strvec_pushl(&cmd.args, "merge", NULL);
655 /* Shared options */
656 argv_push_verbosity(&cmd.args);
657 if (opt_progress)
658 strvec_push(&cmd.args, opt_progress);
660 /* Options passed to git-merge */
661 if (opt_diffstat)
662 strvec_push(&cmd.args, opt_diffstat);
663 if (opt_log)
664 strvec_push(&cmd.args, opt_log);
665 if (opt_signoff)
666 strvec_push(&cmd.args, opt_signoff);
667 if (opt_squash)
668 strvec_push(&cmd.args, opt_squash);
669 if (opt_commit)
670 strvec_push(&cmd.args, opt_commit);
671 if (opt_edit)
672 strvec_push(&cmd.args, opt_edit);
673 if (cleanup_arg)
674 strvec_pushf(&cmd.args, "--cleanup=%s", cleanup_arg);
675 if (opt_ff)
676 strvec_push(&cmd.args, opt_ff);
677 if (opt_verify)
678 strvec_push(&cmd.args, opt_verify);
679 if (opt_verify_signatures)
680 strvec_push(&cmd.args, opt_verify_signatures);
681 strvec_pushv(&cmd.args, opt_strategies.v);
682 strvec_pushv(&cmd.args, opt_strategy_opts.v);
683 if (opt_gpg_sign)
684 strvec_push(&cmd.args, opt_gpg_sign);
685 if (opt_autostash == 0)
686 strvec_push(&cmd.args, "--no-autostash");
687 else if (opt_autostash == 1)
688 strvec_push(&cmd.args, "--autostash");
689 if (opt_allow_unrelated_histories > 0)
690 strvec_push(&cmd.args, "--allow-unrelated-histories");
692 strvec_push(&cmd.args, "FETCH_HEAD");
693 cmd.git_cmd = 1;
694 return run_command(&cmd);
698 * Returns remote's upstream branch for the current branch. If remote is NULL,
699 * the current branch's configured default remote is used. Returns NULL if
700 * `remote` does not name a valid remote, HEAD does not point to a branch,
701 * remote is not the branch's configured remote or the branch does not have any
702 * configured upstream branch.
704 static const char *get_upstream_branch(const char *remote)
706 struct remote *rm;
707 struct branch *curr_branch;
708 const char *curr_branch_remote;
710 rm = remote_get(remote);
711 if (!rm)
712 return NULL;
714 curr_branch = branch_get("HEAD");
715 if (!curr_branch)
716 return NULL;
718 curr_branch_remote = remote_for_branch(curr_branch, NULL);
719 assert(curr_branch_remote);
721 if (strcmp(curr_branch_remote, rm->name))
722 return NULL;
724 return branch_get_upstream(curr_branch, NULL);
728 * Derives the remote-tracking branch from the remote and refspec.
730 * FIXME: The current implementation assumes the default mapping of
731 * refs/heads/<branch_name> to refs/remotes/<remote_name>/<branch_name>.
733 static const char *get_tracking_branch(const char *remote, const char *refspec)
735 struct refspec_item spec;
736 const char *spec_src;
737 const char *merge_branch;
739 refspec_item_init_or_die(&spec, refspec, REFSPEC_FETCH);
740 spec_src = spec.src;
741 if (!*spec_src || !strcmp(spec_src, "HEAD"))
742 spec_src = "HEAD";
743 else if (skip_prefix(spec_src, "heads/", &spec_src))
745 else if (skip_prefix(spec_src, "refs/heads/", &spec_src))
747 else if (starts_with(spec_src, "refs/") ||
748 starts_with(spec_src, "tags/") ||
749 starts_with(spec_src, "remotes/"))
750 spec_src = "";
752 if (*spec_src) {
753 if (!strcmp(remote, "."))
754 merge_branch = mkpath("refs/heads/%s", spec_src);
755 else
756 merge_branch = mkpath("refs/remotes/%s/%s", remote, spec_src);
757 } else
758 merge_branch = NULL;
760 refspec_item_clear(&spec);
761 return merge_branch;
765 * Given the repo and refspecs, sets fork_point to the point at which the
766 * current branch forked from its remote-tracking branch. Returns 0 on success,
767 * -1 on failure.
769 static int get_rebase_fork_point(struct object_id *fork_point, const char *repo,
770 const char *refspec)
772 int ret;
773 struct branch *curr_branch;
774 const char *remote_branch;
775 struct child_process cp = CHILD_PROCESS_INIT;
776 struct strbuf sb = STRBUF_INIT;
778 curr_branch = branch_get("HEAD");
779 if (!curr_branch)
780 return -1;
782 if (refspec)
783 remote_branch = get_tracking_branch(repo, refspec);
784 else
785 remote_branch = get_upstream_branch(repo);
787 if (!remote_branch)
788 return -1;
790 strvec_pushl(&cp.args, "merge-base", "--fork-point",
791 remote_branch, curr_branch->name, NULL);
792 cp.no_stdin = 1;
793 cp.no_stderr = 1;
794 cp.git_cmd = 1;
796 ret = capture_command(&cp, &sb, GIT_MAX_HEXSZ);
797 if (ret)
798 goto cleanup;
800 ret = get_oid_hex(sb.buf, fork_point);
801 if (ret)
802 goto cleanup;
804 cleanup:
805 strbuf_release(&sb);
806 return ret ? -1 : 0;
810 * Sets merge_base to the octopus merge base of curr_head, merge_head and
811 * fork_point. Returns 0 if a merge base is found, 1 otherwise.
813 static int get_octopus_merge_base(struct object_id *merge_base,
814 const struct object_id *curr_head,
815 const struct object_id *merge_head,
816 const struct object_id *fork_point)
818 struct commit_list *revs = NULL, *result = NULL;
820 commit_list_insert(lookup_commit_reference(the_repository, curr_head),
821 &revs);
822 commit_list_insert(lookup_commit_reference(the_repository, merge_head),
823 &revs);
824 if (!is_null_oid(fork_point))
825 commit_list_insert(lookup_commit_reference(the_repository, fork_point),
826 &revs);
828 if (get_octopus_merge_bases(revs, &result) < 0)
829 exit(128);
830 free_commit_list(revs);
831 reduce_heads_replace(&result);
833 if (!result)
834 return 1;
836 oidcpy(merge_base, &result->item->object.oid);
837 free_commit_list(result);
838 return 0;
842 * Given the current HEAD oid, the merge head returned from git-fetch and the
843 * fork point calculated by get_rebase_fork_point(), compute the <newbase> and
844 * <upstream> arguments to use for the upcoming git-rebase invocation.
846 static int get_rebase_newbase_and_upstream(struct object_id *newbase,
847 struct object_id *upstream,
848 const struct object_id *curr_head,
849 const struct object_id *merge_head,
850 const struct object_id *fork_point)
852 struct object_id oct_merge_base;
854 if (!get_octopus_merge_base(&oct_merge_base, curr_head, merge_head, fork_point))
855 if (!is_null_oid(fork_point) && oideq(&oct_merge_base, fork_point))
856 fork_point = NULL;
858 if (fork_point && !is_null_oid(fork_point))
859 oidcpy(upstream, fork_point);
860 else
861 oidcpy(upstream, merge_head);
863 oidcpy(newbase, merge_head);
865 return 0;
869 * Given the <newbase> and <upstream> calculated by
870 * get_rebase_newbase_and_upstream(), runs git-rebase with the
871 * appropriate arguments and returns its exit status.
873 static int run_rebase(const struct object_id *newbase,
874 const struct object_id *upstream)
876 struct child_process cmd = CHILD_PROCESS_INIT;
878 strvec_push(&cmd.args, "rebase");
880 /* Shared options */
881 argv_push_verbosity(&cmd.args);
883 /* Options passed to git-rebase */
884 if (opt_rebase == REBASE_MERGES)
885 strvec_push(&cmd.args, "--rebase-merges");
886 else if (opt_rebase == REBASE_INTERACTIVE)
887 strvec_push(&cmd.args, "--interactive");
888 if (opt_diffstat)
889 strvec_push(&cmd.args, opt_diffstat);
890 strvec_pushv(&cmd.args, opt_strategies.v);
891 strvec_pushv(&cmd.args, opt_strategy_opts.v);
892 if (opt_gpg_sign)
893 strvec_push(&cmd.args, opt_gpg_sign);
894 if (opt_signoff)
895 strvec_push(&cmd.args, opt_signoff);
896 if (opt_autostash == 0)
897 strvec_push(&cmd.args, "--no-autostash");
898 else if (opt_autostash == 1)
899 strvec_push(&cmd.args, "--autostash");
900 if (opt_verify_signatures &&
901 !strcmp(opt_verify_signatures, "--verify-signatures"))
902 warning(_("ignoring --verify-signatures for rebase"));
904 strvec_push(&cmd.args, "--onto");
905 strvec_push(&cmd.args, oid_to_hex(newbase));
907 strvec_push(&cmd.args, oid_to_hex(upstream));
909 cmd.git_cmd = 1;
910 return run_command(&cmd);
913 static int get_can_ff(struct object_id *orig_head,
914 struct oid_array *merge_heads)
916 int ret;
917 struct commit_list *list = NULL;
918 struct commit *merge_head, *head;
919 struct object_id *orig_merge_head;
921 if (merge_heads->nr > 1)
922 return 0;
924 orig_merge_head = &merge_heads->oid[0];
925 head = lookup_commit_reference(the_repository, orig_head);
926 commit_list_insert(head, &list);
927 merge_head = lookup_commit_reference(the_repository, orig_merge_head);
928 ret = repo_is_descendant_of(the_repository, merge_head, list);
929 free_commit_list(list);
930 if (ret < 0)
931 exit(128);
932 return ret;
936 * Is orig_head a descendant of _all_ merge_heads?
937 * Unfortunately is_descendant_of() cannot be used as it asks
938 * if orig_head is a descendant of at least one of them.
940 static int already_up_to_date(struct object_id *orig_head,
941 struct oid_array *merge_heads)
943 int i;
944 struct commit *ours;
946 ours = lookup_commit_reference(the_repository, orig_head);
947 for (i = 0; i < merge_heads->nr; i++) {
948 struct commit_list *list = NULL;
949 struct commit *theirs;
950 int ok;
952 theirs = lookup_commit_reference(the_repository, &merge_heads->oid[i]);
953 commit_list_insert(theirs, &list);
954 ok = repo_is_descendant_of(the_repository, ours, list);
955 free_commit_list(list);
956 if (ok < 0)
957 exit(128);
958 if (!ok)
959 return 0;
961 return 1;
964 static void show_advice_pull_non_ff(void)
966 advise(_("You have divergent branches and need to specify how to reconcile them.\n"
967 "You can do so by running one of the following commands sometime before\n"
968 "your next pull:\n"
969 "\n"
970 " git config pull.rebase false # merge\n"
971 " git config pull.rebase true # rebase\n"
972 " git config pull.ff only # fast-forward only\n"
973 "\n"
974 "You can replace \"git config\" with \"git config --global\" to set a default\n"
975 "preference for all repositories. You can also pass --rebase, --no-rebase,\n"
976 "or --ff-only on the command line to override the configured default per\n"
977 "invocation.\n"));
980 int cmd_pull(int argc, const char **argv, const char *prefix)
982 const char *repo, **refspecs;
983 struct oid_array merge_heads = OID_ARRAY_INIT;
984 struct object_id orig_head, curr_head;
985 struct object_id rebase_fork_point;
986 int rebase_unspecified = 0;
987 int can_ff;
988 int divergent;
989 int ret;
991 if (!getenv("GIT_REFLOG_ACTION"))
992 set_reflog_message(argc, argv);
994 git_config(git_pull_config, NULL);
995 if (the_repository->gitdir) {
996 prepare_repo_settings(the_repository);
997 the_repository->settings.command_requires_full_index = 0;
1000 argc = parse_options(argc, argv, prefix, pull_options, pull_usage, 0);
1002 if (recurse_submodules_cli != RECURSE_SUBMODULES_DEFAULT)
1003 recurse_submodules = recurse_submodules_cli;
1005 if (cleanup_arg)
1007 * this only checks the validity of cleanup_arg; we don't need
1008 * a valid value for use_editor
1010 get_cleanup_mode(cleanup_arg, 0);
1012 parse_repo_refspecs(argc, argv, &repo, &refspecs);
1014 if (!opt_ff) {
1015 opt_ff = xstrdup_or_null(config_get_ff());
1017 * A subtle point: opt_ff was set on the line above via
1018 * reading from config. opt_rebase, in contrast, is set
1019 * before this point via command line options. The setting
1020 * of opt_rebase via reading from config (using
1021 * config_get_rebase()) does not happen until later. We
1022 * are relying on the next if-condition happening before
1023 * the config_get_rebase() call so that an explicit
1024 * "--rebase" can override a config setting of
1025 * pull.ff=only.
1027 if (opt_rebase >= 0 && opt_ff && !strcmp(opt_ff, "--ff-only"))
1028 opt_ff = "--ff";
1031 if (opt_rebase < 0)
1032 opt_rebase = config_get_rebase(&rebase_unspecified);
1034 if (repo_read_index_unmerged(the_repository))
1035 die_resolve_conflict("pull");
1037 if (file_exists(git_path_merge_head(the_repository)))
1038 die_conclude_merge();
1040 if (repo_get_oid(the_repository, "HEAD", &orig_head))
1041 oidclr(&orig_head);
1043 if (opt_rebase) {
1044 if (opt_autostash == -1)
1045 opt_autostash = config_autostash;
1047 if (is_null_oid(&orig_head) && !is_index_unborn(&the_index))
1048 die(_("Updating an unborn branch with changes added to the index."));
1050 if (!opt_autostash)
1051 require_clean_work_tree(the_repository,
1052 N_("pull with rebase"),
1053 _("Please commit or stash them."), 1, 0);
1055 if (get_rebase_fork_point(&rebase_fork_point, repo, *refspecs))
1056 oidclr(&rebase_fork_point);
1059 if (run_fetch(repo, refspecs))
1060 return 1;
1062 if (opt_dry_run)
1063 return 0;
1065 if (repo_get_oid(the_repository, "HEAD", &curr_head))
1066 oidclr(&curr_head);
1068 if (!is_null_oid(&orig_head) && !is_null_oid(&curr_head) &&
1069 !oideq(&orig_head, &curr_head)) {
1071 * The fetch involved updating the current branch.
1073 * The working tree and the index file are still based on
1074 * orig_head commit, but we are merging into curr_head.
1075 * Update the working tree to match curr_head.
1078 warning(_("fetch updated the current branch head.\n"
1079 "fast-forwarding your working tree from\n"
1080 "commit %s."), oid_to_hex(&orig_head));
1082 if (checkout_fast_forward(the_repository, &orig_head,
1083 &curr_head, 0))
1084 die(_("Cannot fast-forward your working tree.\n"
1085 "After making sure that you saved anything precious from\n"
1086 "$ git diff %s\n"
1087 "output, run\n"
1088 "$ git reset --hard\n"
1089 "to recover."), oid_to_hex(&orig_head));
1092 get_merge_heads(&merge_heads);
1094 if (!merge_heads.nr)
1095 die_no_merge_candidates(repo, refspecs);
1097 if (is_null_oid(&orig_head)) {
1098 if (merge_heads.nr > 1)
1099 die(_("Cannot merge multiple branches into empty head."));
1100 ret = pull_into_void(merge_heads.oid, &curr_head);
1101 goto cleanup;
1103 if (merge_heads.nr > 1) {
1104 if (opt_rebase)
1105 die(_("Cannot rebase onto multiple branches."));
1106 if (opt_ff && !strcmp(opt_ff, "--ff-only"))
1107 die(_("Cannot fast-forward to multiple branches."));
1110 can_ff = get_can_ff(&orig_head, &merge_heads);
1111 divergent = !can_ff && !already_up_to_date(&orig_head, &merge_heads);
1113 /* ff-only takes precedence over rebase */
1114 if (opt_ff && !strcmp(opt_ff, "--ff-only")) {
1115 if (divergent)
1116 die_ff_impossible();
1117 opt_rebase = REBASE_FALSE;
1119 /* If no action specified and we can't fast forward, then warn. */
1120 if (!opt_ff && rebase_unspecified && divergent) {
1121 show_advice_pull_non_ff();
1122 die(_("Need to specify how to reconcile divergent branches."));
1125 if (opt_rebase) {
1126 struct object_id newbase;
1127 struct object_id upstream;
1128 get_rebase_newbase_and_upstream(&newbase, &upstream, &curr_head,
1129 merge_heads.oid, &rebase_fork_point);
1131 if ((recurse_submodules == RECURSE_SUBMODULES_ON ||
1132 recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) &&
1133 submodule_touches_in_range(the_repository, &upstream, &curr_head))
1134 die(_("cannot rebase with locally recorded submodule modifications"));
1136 if (can_ff) {
1137 /* we can fast-forward this without invoking rebase */
1138 opt_ff = "--ff-only";
1139 ret = run_merge();
1140 } else {
1141 ret = run_rebase(&newbase, &upstream);
1144 if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON ||
1145 recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND))
1146 ret = rebase_submodules();
1148 goto cleanup;
1149 } else {
1150 ret = run_merge();
1151 if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON ||
1152 recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND))
1153 ret = update_submodules();
1154 goto cleanup;
1157 cleanup:
1158 oid_array_clear(&merge_heads);
1159 return ret;