7048fdf0057383e84a73f8cf55374b13beda0b2e
1/*
2 * Builtin "git pull"
3 *
4 * Based on git-pull.sh by Junio C Hamano
5 *
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 "submodule.h"
19#include "submodule-config.h"
20#include "tempfile.h"
21#include "lockfile.h"
22#include "wt-status.h"
23enum rebase_type {
25 REBASE_INVALID = -1,
26 REBASE_FALSE = 0,
27 REBASE_TRUE,
28 REBASE_PRESERVE,
29 REBASE_INTERACTIVE
30};
31/**
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 * "preserve", returns REBASE_PRESERVE. If value is a invalid value, dies with
36 * a fatal error if fatal is true, otherwise returns REBASE_INVALID.
37 */
38static enum rebase_type parse_config_rebase(const char *key, const char *value,
39 int fatal)
40{
41 int v = git_config_maybe_bool("pull.rebase", value);
42 if (!v)
44 return REBASE_FALSE;
45 else if (v > 0)
46 return REBASE_TRUE;
47 else if (!strcmp(value, "preserve"))
48 return REBASE_PRESERVE;
49 else if (!strcmp(value, "interactive"))
50 return REBASE_INTERACTIVE;
51 if (fatal)
53 die(_("Invalid value for %s: %s"), key, value);
54 else
55 error(_("Invalid value for %s: %s"), key, value);
56 return REBASE_INVALID;
58}
59/**
61 * Callback for --rebase, which parses arg with parse_config_rebase().
62 */
63static int parse_opt_rebase(const struct option *opt, const char *arg, int unset)
64{
65 enum rebase_type *value = opt->value;
66 if (arg)
68 *value = parse_config_rebase("--rebase", arg, 0);
69 else
70 *value = unset ? REBASE_FALSE : REBASE_TRUE;
71 return *value == REBASE_INVALID ? -1 : 0;
72}
73static const char * const pull_usage[] = {
75 N_("git pull [<options>] [<repository> [<refspec>...]]"),
76 NULL
77};
78/* Shared options */
80static int opt_verbosity;
81static char *opt_progress;
82static int recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
83/* Options passed to git-merge or git-rebase */
85static enum rebase_type opt_rebase = -1;
86static char *opt_diffstat;
87static char *opt_log;
88static char *opt_squash;
89static char *opt_commit;
90static char *opt_edit;
91static char *opt_ff;
92static char *opt_verify_signatures;
93static int opt_autostash = -1;
94static int config_autostash;
95static struct argv_array opt_strategies = ARGV_ARRAY_INIT;
96static struct argv_array opt_strategy_opts = ARGV_ARRAY_INIT;
97static char *opt_gpg_sign;
98static int opt_allow_unrelated_histories;
99/* Options passed to git-fetch */
101static char *opt_all;
102static char *opt_append;
103static char *opt_upload_pack;
104static int opt_force;
105static char *opt_tags;
106static char *opt_prune;
107static char *max_children;
108static int opt_dry_run;
109static char *opt_keep;
110static char *opt_depth;
111static char *opt_unshallow;
112static char *opt_update_shallow;
113static char *opt_refmap;
114static struct option pull_options[] = {
116 /* Shared options */
117 OPT__VERBOSITY(&opt_verbosity),
118 OPT_PASSTHRU(0, "progress", &opt_progress, NULL,
119 N_("force progress reporting"),
120 PARSE_OPT_NOARG),
121 { OPTION_CALLBACK, 0, "recurse-submodules",
122 &recurse_submodules, N_("on-demand"),
123 N_("control for recursive fetching of submodules"),
124 PARSE_OPT_OPTARG, option_fetch_parse_recurse_submodules },
125 /* Options passed to git-merge or git-rebase */
127 OPT_GROUP(N_("Options related to merging")),
128 { OPTION_CALLBACK, 'r', "rebase", &opt_rebase,
129 "false|true|preserve|interactive",
130 N_("incorporate changes by rebasing rather than merging"),
131 PARSE_OPT_OPTARG, parse_opt_rebase },
132 OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL,
133 N_("do not show a diffstat at the end of the merge"),
134 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
135 OPT_PASSTHRU(0, "stat", &opt_diffstat, NULL,
136 N_("show a diffstat at the end of the merge"),
137 PARSE_OPT_NOARG),
138 OPT_PASSTHRU(0, "summary", &opt_diffstat, NULL,
139 N_("(synonym to --stat)"),
140 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN),
141 OPT_PASSTHRU(0, "log", &opt_log, N_("n"),
142 N_("add (at most <n>) entries from shortlog to merge commit message"),
143 PARSE_OPT_OPTARG),
144 OPT_PASSTHRU(0, "squash", &opt_squash, NULL,
145 N_("create a single commit instead of doing a merge"),
146 PARSE_OPT_NOARG),
147 OPT_PASSTHRU(0, "commit", &opt_commit, NULL,
148 N_("perform a commit if the merge succeeds (default)"),
149 PARSE_OPT_NOARG),
150 OPT_PASSTHRU(0, "edit", &opt_edit, NULL,
151 N_("edit message before committing"),
152 PARSE_OPT_NOARG),
153 OPT_PASSTHRU(0, "ff", &opt_ff, NULL,
154 N_("allow fast-forward"),
155 PARSE_OPT_NOARG),
156 OPT_PASSTHRU(0, "ff-only", &opt_ff, NULL,
157 N_("abort if fast-forward is not possible"),
158 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
159 OPT_PASSTHRU(0, "verify-signatures", &opt_verify_signatures, NULL,
160 N_("verify that the named commit has a valid GPG signature"),
161 PARSE_OPT_NOARG),
162 OPT_BOOL(0, "autostash", &opt_autostash,
163 N_("automatically stash/stash pop before and after rebase")),
164 OPT_PASSTHRU_ARGV('s', "strategy", &opt_strategies, N_("strategy"),
165 N_("merge strategy to use"),
166 0),
167 OPT_PASSTHRU_ARGV('X', "strategy-option", &opt_strategy_opts,
168 N_("option=value"),
169 N_("option for selected merge strategy"),
170 0),
171 OPT_PASSTHRU('S', "gpg-sign", &opt_gpg_sign, N_("key-id"),
172 N_("GPG sign commit"),
173 PARSE_OPT_OPTARG),
174 OPT_SET_INT(0, "allow-unrelated-histories",
175 &opt_allow_unrelated_histories,
176 N_("allow merging unrelated histories"), 1),
177 /* Options passed to git-fetch */
179 OPT_GROUP(N_("Options related to fetching")),
180 OPT_PASSTHRU(0, "all", &opt_all, NULL,
181 N_("fetch from all remotes"),
182 PARSE_OPT_NOARG),
183 OPT_PASSTHRU('a', "append", &opt_append, NULL,
184 N_("append to .git/FETCH_HEAD instead of overwriting"),
185 PARSE_OPT_NOARG),
186 OPT_PASSTHRU(0, "upload-pack", &opt_upload_pack, N_("path"),
187 N_("path to upload pack on remote end"),
188 0),
189 OPT__FORCE(&opt_force, N_("force overwrite of local branch")),
190 OPT_PASSTHRU('t', "tags", &opt_tags, NULL,
191 N_("fetch all tags and associated objects"),
192 PARSE_OPT_NOARG),
193 OPT_PASSTHRU('p', "prune", &opt_prune, NULL,
194 N_("prune remote-tracking branches no longer on remote"),
195 PARSE_OPT_NOARG),
196 OPT_PASSTHRU('j', "jobs", &max_children, N_("n"),
197 N_("number of submodules pulled in parallel"),
198 PARSE_OPT_OPTARG),
199 OPT_BOOL(0, "dry-run", &opt_dry_run,
200 N_("dry run")),
201 OPT_PASSTHRU('k', "keep", &opt_keep, NULL,
202 N_("keep downloaded pack"),
203 PARSE_OPT_NOARG),
204 OPT_PASSTHRU(0, "depth", &opt_depth, N_("depth"),
205 N_("deepen history of shallow clone"),
206 0),
207 OPT_PASSTHRU(0, "unshallow", &opt_unshallow, NULL,
208 N_("convert to a complete repository"),
209 PARSE_OPT_NONEG | PARSE_OPT_NOARG),
210 OPT_PASSTHRU(0, "update-shallow", &opt_update_shallow, NULL,
211 N_("accept refs that update .git/shallow"),
212 PARSE_OPT_NOARG),
213 OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"),
214 N_("specify fetch refmap"),
215 PARSE_OPT_NONEG),
216 OPT_END()
218};
219/**
221 * Pushes "-q" or "-v" switches into arr to match the opt_verbosity level.
222 */
223static void argv_push_verbosity(struct argv_array *arr)
224{
225 int verbosity;
226 for (verbosity = opt_verbosity; verbosity > 0; verbosity--)
228 argv_array_push(arr, "-v");
229 for (verbosity = opt_verbosity; verbosity < 0; verbosity++)
231 argv_array_push(arr, "-q");
232}
233/**
235 * Pushes "-f" switches into arr to match the opt_force level.
236 */
237static void argv_push_force(struct argv_array *arr)
238{
239 int force = opt_force;
240 while (force-- > 0)
241 argv_array_push(arr, "-f");
242}
243/**
245 * Sets the GIT_REFLOG_ACTION environment variable to the concatenation of argv
246 */
247static void set_reflog_message(int argc, const char **argv)
248{
249 int i;
250 struct strbuf msg = STRBUF_INIT;
251 for (i = 0; i < argc; i++) {
253 if (i)
254 strbuf_addch(&msg, ' ');
255 strbuf_addstr(&msg, argv[i]);
256 }
257 setenv("GIT_REFLOG_ACTION", msg.buf, 0);
259 strbuf_release(&msg);
261}
262/**
264 * If pull.ff is unset, returns NULL. If pull.ff is "true", returns "--ff". If
265 * pull.ff is "false", returns "--no-ff". If pull.ff is "only", returns
266 * "--ff-only". Otherwise, if pull.ff is set to an invalid value, die with an
267 * error.
268 */
269static const char *config_get_ff(void)
270{
271 const char *value;
272 if (git_config_get_value("pull.ff", &value))
274 return NULL;
275 switch (git_config_maybe_bool("pull.ff", value)) {
277 case 0:
278 return "--no-ff";
279 case 1:
280 return "--ff";
281 }
282 if (!strcmp(value, "only"))
284 return "--ff-only";
285 die(_("Invalid value for pull.ff: %s"), value);
287}
288/**
290 * Returns the default configured value for --rebase. It first looks for the
291 * value of "branch.$curr_branch.rebase", where $curr_branch is the current
292 * branch, and if HEAD is detached or the configuration key does not exist,
293 * looks for the value of "pull.rebase". If both configuration keys do not
294 * exist, returns REBASE_FALSE.
295 */
296static enum rebase_type config_get_rebase(void)
297{
298 struct branch *curr_branch = branch_get("HEAD");
299 const char *value;
300 if (curr_branch) {
302 char *key = xstrfmt("branch.%s.rebase", curr_branch->name);
303 if (!git_config_get_value(key, &value)) {
305 enum rebase_type ret = parse_config_rebase(key, value, 1);
306 free(key);
307 return ret;
308 }
309 free(key);
311 }
312 if (!git_config_get_value("pull.rebase", &value))
314 return parse_config_rebase("pull.rebase", value, 1);
315 return REBASE_FALSE;
317}
318/**
320 * Read config variables.
321 */
322static int git_pull_config(const char *var, const char *value, void *cb)
323{
324 if (!strcmp(var, "rebase.autostash")) {
325 config_autostash = git_config_bool(var, value);
326 return 0;
327 }
328 return git_default_config(var, value, cb);
329}
330/**
332 * Appends merge candidates from FETCH_HEAD that are not marked not-for-merge
333 * into merge_heads.
334 */
335static void get_merge_heads(struct oid_array *merge_heads)
336{
337 const char *filename = git_path_fetch_head();
338 FILE *fp;
339 struct strbuf sb = STRBUF_INIT;
340 struct object_id oid;
341 fp = xfopen(filename, "r");
343 while (strbuf_getline_lf(&sb, fp) != EOF) {
344 if (get_oid_hex(sb.buf, &oid))
345 continue; /* invalid line: does not start with SHA1 */
346 if (starts_with(sb.buf + GIT_SHA1_HEXSZ, "\tnot-for-merge\t"))
347 continue; /* ref is not-for-merge */
348 oid_array_append(merge_heads, &oid);
349 }
350 fclose(fp);
351 strbuf_release(&sb);
352}
353/**
355 * Used by die_no_merge_candidates() as a for_each_remote() callback to
356 * retrieve the name of the remote if the repository only has one remote.
357 */
358static int get_only_remote(struct remote *remote, void *cb_data)
359{
360 const char **remote_name = cb_data;
361 if (*remote_name)
363 return -1;
364 *remote_name = remote->name;
366 return 0;
367}
368/**
370 * Dies with the appropriate reason for why there are no merge candidates:
371 *
372 * 1. We fetched from a specific remote, and a refspec was given, but it ended
373 * up not fetching anything. This is usually because the user provided a
374 * wildcard refspec which had no matches on the remote end.
375 *
376 * 2. We fetched from a non-default remote, but didn't specify a branch to
377 * merge. We can't use the configured one because it applies to the default
378 * remote, thus the user must specify the branches to merge.
379 *
380 * 3. We fetched from the branch's or repo's default remote, but:
381 *
382 * a. We are not on a branch, so there will never be a configured branch to
383 * merge with.
384 *
385 * b. We are on a branch, but there is no configured branch to merge with.
386 *
387 * 4. We fetched from the branch's or repo's default remote, but the configured
388 * branch to merge didn't get fetched. (Either it doesn't exist, or wasn't
389 * part of the configured fetch refspec.)
390 */
391static void NORETURN die_no_merge_candidates(const char *repo, const char **refspecs)
392{
393 struct branch *curr_branch = branch_get("HEAD");
394 const char *remote = curr_branch ? curr_branch->remote_name : NULL;
395 if (*refspecs) {
397 if (opt_rebase)
398 fprintf_ln(stderr, _("There is no candidate for rebasing against among the refs that you just fetched."));
399 else
400 fprintf_ln(stderr, _("There are no candidates for merging among the refs that you just fetched."));
401 fprintf_ln(stderr, _("Generally this means that you provided a wildcard refspec which had no\n"
402 "matches on the remote end."));
403 } else if (repo && curr_branch && (!remote || strcmp(repo, remote))) {
404 fprintf_ln(stderr, _("You asked to pull from the remote '%s', but did not specify\n"
405 "a branch. Because this is not the default configured remote\n"
406 "for your current branch, you must specify a branch on the command line."),
407 repo);
408 } else if (!curr_branch) {
409 fprintf_ln(stderr, _("You are not currently on a branch."));
410 if (opt_rebase)
411 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
412 else
413 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
414 fprintf_ln(stderr, _("See git-pull(1) for details."));
415 fprintf(stderr, "\n");
416 fprintf_ln(stderr, " git pull %s %s", _("<remote>"), _("<branch>"));
417 fprintf(stderr, "\n");
418 } else if (!curr_branch->merge_nr) {
419 const char *remote_name = NULL;
420 if (for_each_remote(get_only_remote, &remote_name) || !remote_name)
422 remote_name = _("<remote>");
423 fprintf_ln(stderr, _("There is no tracking information for the current branch."));
425 if (opt_rebase)
426 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
427 else
428 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
429 fprintf_ln(stderr, _("See git-pull(1) for details."));
430 fprintf(stderr, "\n");
431 fprintf_ln(stderr, " git pull %s %s", _("<remote>"), _("<branch>"));
432 fprintf(stderr, "\n");
433 fprintf_ln(stderr, _("If you wish to set tracking information for this branch you can do so with:"));
434 fprintf(stderr, "\n");
435 fprintf_ln(stderr, " git branch --set-upstream-to=%s/%s %s\n",
436 remote_name, _("<branch>"), curr_branch->name);
437 } else
438 fprintf_ln(stderr, _("Your configuration specifies to merge with the ref '%s'\n"
439 "from the remote, but no such ref was fetched."),
440 *curr_branch->merge_name);
441 exit(1);
442}
443/**
445 * Parses argv into [<repo> [<refspecs>...]], returning their values in `repo`
446 * as a string and `refspecs` as a null-terminated array of strings. If `repo`
447 * is not provided in argv, it is set to NULL.
448 */
449static void parse_repo_refspecs(int argc, const char **argv, const char **repo,
450 const char ***refspecs)
451{
452 if (argc > 0) {
453 *repo = *argv++;
454 argc--;
455 } else
456 *repo = NULL;
457 *refspecs = argv;
458}
459/**
461 * Runs git-fetch, returning its exit status. `repo` and `refspecs` are the
462 * repository and refspecs to fetch, or NULL if they are not provided.
463 */
464static int run_fetch(const char *repo, const char **refspecs)
465{
466 struct argv_array args = ARGV_ARRAY_INIT;
467 int ret;
468 argv_array_pushl(&args, "fetch", "--update-head-ok", NULL);
470 /* Shared options */
472 argv_push_verbosity(&args);
473 if (opt_progress)
474 argv_array_push(&args, opt_progress);
475 /* Options passed to git-fetch */
477 if (opt_all)
478 argv_array_push(&args, opt_all);
479 if (opt_append)
480 argv_array_push(&args, opt_append);
481 if (opt_upload_pack)
482 argv_array_push(&args, opt_upload_pack);
483 argv_push_force(&args);
484 if (opt_tags)
485 argv_array_push(&args, opt_tags);
486 if (opt_prune)
487 argv_array_push(&args, opt_prune);
488 if (recurse_submodules != RECURSE_SUBMODULES_DEFAULT)
489 switch (recurse_submodules) {
490 case RECURSE_SUBMODULES_ON:
491 argv_array_push(&args, "--recurse-submodules=on");
492 break;
493 case RECURSE_SUBMODULES_OFF:
494 argv_array_push(&args, "--recurse-submodules=no");
495 break;
496 case RECURSE_SUBMODULES_ON_DEMAND:
497 argv_array_push(&args, "--recurse-submodules=on-demand");
498 break;
499 default:
500 BUG("submodule recursion option not understood");
501 }
502 if (max_children)
503 argv_array_push(&args, max_children);
504 if (opt_dry_run)
505 argv_array_push(&args, "--dry-run");
506 if (opt_keep)
507 argv_array_push(&args, opt_keep);
508 if (opt_depth)
509 argv_array_push(&args, opt_depth);
510 if (opt_unshallow)
511 argv_array_push(&args, opt_unshallow);
512 if (opt_update_shallow)
513 argv_array_push(&args, opt_update_shallow);
514 if (opt_refmap)
515 argv_array_push(&args, opt_refmap);
516 if (repo) {
518 argv_array_push(&args, repo);
519 argv_array_pushv(&args, refspecs);
520 } else if (*refspecs)
521 die("BUG: refspecs without repo?");
522 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
523 argv_array_clear(&args);
524 return ret;
525}
526/**
528 * "Pulls into void" by branching off merge_head.
529 */
530static int pull_into_void(const struct object_id *merge_head,
531 const struct object_id *curr_head)
532{
533 /*
534 * Two-way merge: we treat the index as based on an empty tree,
535 * and try to fast-forward to HEAD. This ensures we will not lose
536 * index/worktree changes that the user already made on the unborn
537 * branch.
538 */
539 if (checkout_fast_forward(&empty_tree_oid, merge_head, 0))
540 return 1;
541 if (update_ref("initial pull", "HEAD", merge_head->hash, curr_head->hash, 0, UPDATE_REFS_DIE_ON_ERR))
543 return 1;
544 return 0;
546}
547static int rebase_submodules(void)
549{
550 struct child_process cp = CHILD_PROCESS_INIT;
551 cp.git_cmd = 1;
553 cp.no_stdin = 1;
554 argv_array_pushl(&cp.args, "submodule", "update",
555 "--recursive", "--rebase", NULL);
556 return run_command(&cp);
558}
559static int update_submodules(void)
561{
562 struct child_process cp = CHILD_PROCESS_INIT;
563 cp.git_cmd = 1;
565 cp.no_stdin = 1;
566 argv_array_pushl(&cp.args, "submodule", "update",
567 "--recursive", "--checkout", NULL);
568 return run_command(&cp);
570}
571/**
573 * Runs git-merge, returning its exit status.
574 */
575static int run_merge(void)
576{
577 int ret;
578 struct argv_array args = ARGV_ARRAY_INIT;
579 argv_array_pushl(&args, "merge", NULL);
581 /* Shared options */
583 argv_push_verbosity(&args);
584 if (opt_progress)
585 argv_array_push(&args, opt_progress);
586 /* Options passed to git-merge */
588 if (opt_diffstat)
589 argv_array_push(&args, opt_diffstat);
590 if (opt_log)
591 argv_array_push(&args, opt_log);
592 if (opt_squash)
593 argv_array_push(&args, opt_squash);
594 if (opt_commit)
595 argv_array_push(&args, opt_commit);
596 if (opt_edit)
597 argv_array_push(&args, opt_edit);
598 if (opt_ff)
599 argv_array_push(&args, opt_ff);
600 if (opt_verify_signatures)
601 argv_array_push(&args, opt_verify_signatures);
602 argv_array_pushv(&args, opt_strategies.argv);
603 argv_array_pushv(&args, opt_strategy_opts.argv);
604 if (opt_gpg_sign)
605 argv_array_push(&args, opt_gpg_sign);
606 if (opt_allow_unrelated_histories > 0)
607 argv_array_push(&args, "--allow-unrelated-histories");
608 argv_array_push(&args, "FETCH_HEAD");
610 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
611 argv_array_clear(&args);
612 return ret;
613}
614/**
616 * Returns remote's upstream branch for the current branch. If remote is NULL,
617 * the current branch's configured default remote is used. Returns NULL if
618 * `remote` does not name a valid remote, HEAD does not point to a branch,
619 * remote is not the branch's configured remote or the branch does not have any
620 * configured upstream branch.
621 */
622static const char *get_upstream_branch(const char *remote)
623{
624 struct remote *rm;
625 struct branch *curr_branch;
626 const char *curr_branch_remote;
627 rm = remote_get(remote);
629 if (!rm)
630 return NULL;
631 curr_branch = branch_get("HEAD");
633 if (!curr_branch)
634 return NULL;
635 curr_branch_remote = remote_for_branch(curr_branch, NULL);
637 assert(curr_branch_remote);
638 if (strcmp(curr_branch_remote, rm->name))
640 return NULL;
641 return branch_get_upstream(curr_branch, NULL);
643}
644/**
646 * Derives the remote tracking branch from the remote and refspec.
647 *
648 * FIXME: The current implementation assumes the default mapping of
649 * refs/heads/<branch_name> to refs/remotes/<remote_name>/<branch_name>.
650 */
651static const char *get_tracking_branch(const char *remote, const char *refspec)
652{
653 struct refspec *spec;
654 const char *spec_src;
655 const char *merge_branch;
656 spec = parse_fetch_refspec(1, &refspec);
658 spec_src = spec->src;
659 if (!*spec_src || !strcmp(spec_src, "HEAD"))
660 spec_src = "HEAD";
661 else if (skip_prefix(spec_src, "heads/", &spec_src))
662 ;
663 else if (skip_prefix(spec_src, "refs/heads/", &spec_src))
664 ;
665 else if (starts_with(spec_src, "refs/") ||
666 starts_with(spec_src, "tags/") ||
667 starts_with(spec_src, "remotes/"))
668 spec_src = "";
669 if (*spec_src) {
671 if (!strcmp(remote, "."))
672 merge_branch = mkpath("refs/heads/%s", spec_src);
673 else
674 merge_branch = mkpath("refs/remotes/%s/%s", remote, spec_src);
675 } else
676 merge_branch = NULL;
677 free_refspec(1, spec);
679 return merge_branch;
680}
681/**
683 * Given the repo and refspecs, sets fork_point to the point at which the
684 * current branch forked from its remote tracking branch. Returns 0 on success,
685 * -1 on failure.
686 */
687static int get_rebase_fork_point(struct object_id *fork_point, const char *repo,
688 const char *refspec)
689{
690 int ret;
691 struct branch *curr_branch;
692 const char *remote_branch;
693 struct child_process cp = CHILD_PROCESS_INIT;
694 struct strbuf sb = STRBUF_INIT;
695 curr_branch = branch_get("HEAD");
697 if (!curr_branch)
698 return -1;
699 if (refspec)
701 remote_branch = get_tracking_branch(repo, refspec);
702 else
703 remote_branch = get_upstream_branch(repo);
704 if (!remote_branch)
706 return -1;
707 argv_array_pushl(&cp.args, "merge-base", "--fork-point",
709 remote_branch, curr_branch->name, NULL);
710 cp.no_stdin = 1;
711 cp.no_stderr = 1;
712 cp.git_cmd = 1;
713 ret = capture_command(&cp, &sb, GIT_SHA1_HEXSZ);
715 if (ret)
716 goto cleanup;
717 ret = get_oid_hex(sb.buf, fork_point);
719 if (ret)
720 goto cleanup;
721cleanup:
723 strbuf_release(&sb);
724 return ret ? -1 : 0;
725}
726/**
728 * Sets merge_base to the octopus merge base of curr_head, merge_head and
729 * fork_point. Returns 0 if a merge base is found, 1 otherwise.
730 */
731static int get_octopus_merge_base(struct object_id *merge_base,
732 const struct object_id *curr_head,
733 const struct object_id *merge_head,
734 const struct object_id *fork_point)
735{
736 struct commit_list *revs = NULL, *result;
737 commit_list_insert(lookup_commit_reference(curr_head), &revs);
739 commit_list_insert(lookup_commit_reference(merge_head), &revs);
740 if (!is_null_oid(fork_point))
741 commit_list_insert(lookup_commit_reference(fork_point), &revs);
742 result = reduce_heads(get_octopus_merge_bases(revs));
744 free_commit_list(revs);
745 if (!result)
746 return 1;
747 oidcpy(merge_base, &result->item->object.oid);
749 return 0;
750}
751/**
753 * Given the current HEAD SHA1, the merge head returned from git-fetch and the
754 * fork point calculated by get_rebase_fork_point(), runs git-rebase with the
755 * appropriate arguments and returns its exit status.
756 */
757static int run_rebase(const struct object_id *curr_head,
758 const struct object_id *merge_head,
759 const struct object_id *fork_point)
760{
761 int ret;
762 struct object_id oct_merge_base;
763 struct argv_array args = ARGV_ARRAY_INIT;
764 if (!get_octopus_merge_base(&oct_merge_base, curr_head, merge_head, fork_point))
766 if (!is_null_oid(fork_point) && !oidcmp(&oct_merge_base, fork_point))
767 fork_point = NULL;
768 argv_array_push(&args, "rebase");
770 /* Shared options */
772 argv_push_verbosity(&args);
773 /* Options passed to git-rebase */
775 if (opt_rebase == REBASE_PRESERVE)
776 argv_array_push(&args, "--preserve-merges");
777 else if (opt_rebase == REBASE_INTERACTIVE)
778 argv_array_push(&args, "--interactive");
779 if (opt_diffstat)
780 argv_array_push(&args, opt_diffstat);
781 argv_array_pushv(&args, opt_strategies.argv);
782 argv_array_pushv(&args, opt_strategy_opts.argv);
783 if (opt_gpg_sign)
784 argv_array_push(&args, opt_gpg_sign);
785 if (opt_autostash == 0)
786 argv_array_push(&args, "--no-autostash");
787 else if (opt_autostash == 1)
788 argv_array_push(&args, "--autostash");
789 if (opt_verify_signatures &&
790 !strcmp(opt_verify_signatures, "--verify-signatures"))
791 warning(_("ignoring --verify-signatures for rebase"));
792 argv_array_push(&args, "--onto");
794 argv_array_push(&args, oid_to_hex(merge_head));
795 if (fork_point && !is_null_oid(fork_point))
797 argv_array_push(&args, oid_to_hex(fork_point));
798 else
799 argv_array_push(&args, oid_to_hex(merge_head));
800 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
802 argv_array_clear(&args);
803 return ret;
804}
805int cmd_pull(int argc, const char **argv, const char *prefix)
807{
808 const char *repo, **refspecs;
809 struct oid_array merge_heads = OID_ARRAY_INIT;
810 struct object_id orig_head, curr_head;
811 struct object_id rebase_fork_point;
812 int autostash;
813 if (!getenv("GIT_REFLOG_ACTION"))
815 set_reflog_message(argc, argv);
816 argc = parse_options(argc, argv, prefix, pull_options, pull_usage, 0);
818 parse_repo_refspecs(argc, argv, &repo, &refspecs);
820 if (!opt_ff)
822 opt_ff = xstrdup_or_null(config_get_ff());
823 if (opt_rebase < 0)
825 opt_rebase = config_get_rebase();
826 git_config(git_pull_config, NULL);
828 if (read_cache_unmerged())
830 die_resolve_conflict("pull");
831 if (file_exists(git_path_merge_head()))
833 die_conclude_merge();
834 if (get_oid("HEAD", &orig_head))
836 oidclr(&orig_head);
837 if (!opt_rebase && opt_autostash != -1)
839 die(_("--[no-]autostash option is only valid with --rebase."));
840 autostash = config_autostash;
842 if (opt_rebase) {
843 if (opt_autostash != -1)
844 autostash = opt_autostash;
845 if (is_null_oid(&orig_head) && !is_cache_unborn())
847 die(_("Updating an unborn branch with changes added to the index."));
848 if (!autostash)
850 require_clean_work_tree(N_("pull with rebase"),
851 _("please commit or stash them."), 1, 0);
852 if (get_rebase_fork_point(&rebase_fork_point, repo, *refspecs))
854 oidclr(&rebase_fork_point);
855 }
856 if (run_fetch(repo, refspecs))
858 return 1;
859 if (opt_dry_run)
861 return 0;
862 if (get_oid("HEAD", &curr_head))
864 oidclr(&curr_head);
865 if (!is_null_oid(&orig_head) && !is_null_oid(&curr_head) &&
867 oidcmp(&orig_head, &curr_head)) {
868 /*
869 * The fetch involved updating the current branch.
870 *
871 * The working tree and the index file are still based on
872 * orig_head commit, but we are merging into curr_head.
873 * Update the working tree to match curr_head.
874 */
875 warning(_("fetch updated the current branch head.\n"
877 "fast-forwarding your working tree from\n"
878 "commit %s."), oid_to_hex(&orig_head));
879 if (checkout_fast_forward(&orig_head, &curr_head, 0))
881 die(_("Cannot fast-forward your working tree.\n"
882 "After making sure that you saved anything precious from\n"
883 "$ git diff %s\n"
884 "output, run\n"
885 "$ git reset --hard\n"
886 "to recover."), oid_to_hex(&orig_head));
887 }
888 get_merge_heads(&merge_heads);
890 if (!merge_heads.nr)
892 die_no_merge_candidates(repo, refspecs);
893 if (is_null_oid(&orig_head)) {
895 if (merge_heads.nr > 1)
896 die(_("Cannot merge multiple branches into empty head."));
897 return pull_into_void(merge_heads.oid, &curr_head);
898 }
899 if (opt_rebase && merge_heads.nr > 1)
900 die(_("Cannot rebase onto multiple branches."));
901 if (opt_rebase) {
903 int ret = 0;
904 if ((recurse_submodules == RECURSE_SUBMODULES_ON ||
905 recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) &&
906 submodule_touches_in_range(&rebase_fork_point, &curr_head))
907 die(_("cannot rebase with locally recorded submodule modifications"));
908 if (!autostash) {
909 struct commit_list *list = NULL;
910 struct commit *merge_head, *head;
911 head = lookup_commit_reference(&orig_head);
913 commit_list_insert(head, &list);
914 merge_head = lookup_commit_reference(&merge_heads.oid[0]);
915 if (is_descendant_of(merge_head, list)) {
916 /* we can fast-forward this without invoking rebase */
917 opt_ff = "--ff-only";
918 ret = run_merge();
919 }
920 }
921 ret = run_rebase(&curr_head, merge_heads.oid, &rebase_fork_point);
922 if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON ||
924 recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND))
925 ret = rebase_submodules();
926 return ret;
928 } else {
929 int ret = run_merge();
930 if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON ||
931 recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND))
932 ret = update_submodules();
933 return ret;
934 }
935}