]> git.ipfire.org Git - thirdparty/git.git/blob - builtin/pull.c
Merge branch 'jk/clone-allow-bare-and-o-together'
[thirdparty/git.git] / builtin / pull.c
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 #define USE_THE_INDEX_COMPATIBILITY_MACROS
9 #include "cache.h"
10 #include "config.h"
11 #include "builtin.h"
12 #include "parse-options.h"
13 #include "exec-cmd.h"
14 #include "run-command.h"
15 #include "oid-array.h"
16 #include "remote.h"
17 #include "dir.h"
18 #include "rebase.h"
19 #include "refs.h"
20 #include "refspec.h"
21 #include "revision.h"
22 #include "submodule.h"
23 #include "submodule-config.h"
24 #include "tempfile.h"
25 #include "lockfile.h"
26 #include "wt-status.h"
27 #include "commit-reach.h"
28 #include "sequencer.h"
29 #include "packfile.h"
30
31 /**
32 * Parses the value of --rebase. If value is a false value, returns
33 * REBASE_FALSE. If value is a true value, returns REBASE_TRUE. If value is
34 * "merges", returns REBASE_MERGES. If value is a invalid value, dies with
35 * a fatal error if fatal is true, otherwise returns REBASE_INVALID.
36 */
37 static enum rebase_type parse_config_rebase(const char *key, const char *value,
38 int fatal)
39 {
40 enum rebase_type v = rebase_parse_value(value);
41 if (v != REBASE_INVALID)
42 return v;
43
44 if (fatal)
45 die(_("invalid value for '%s': '%s'"), key, value);
46 else
47 error(_("invalid value for '%s': '%s'"), key, value);
48
49 return REBASE_INVALID;
50 }
51
52 /**
53 * Callback for --rebase, which parses arg with parse_config_rebase().
54 */
55 static int parse_opt_rebase(const struct option *opt, const char *arg, int unset)
56 {
57 enum rebase_type *value = opt->value;
58
59 if (arg)
60 *value = parse_config_rebase("--rebase", arg, 0);
61 else
62 *value = unset ? REBASE_FALSE : REBASE_TRUE;
63 return *value == REBASE_INVALID ? -1 : 0;
64 }
65
66 static const char * const pull_usage[] = {
67 N_("git pull [<options>] [<repository> [<refspec>...]]"),
68 NULL
69 };
70
71 /* Shared options */
72 static int opt_verbosity;
73 static char *opt_progress;
74 static int recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
75 static int recurse_submodules_cli = RECURSE_SUBMODULES_DEFAULT;
76
77 /* Options passed to git-merge or git-rebase */
78 static enum rebase_type opt_rebase = -1;
79 static char *opt_diffstat;
80 static char *opt_log;
81 static char *opt_signoff;
82 static char *opt_squash;
83 static char *opt_commit;
84 static char *opt_edit;
85 static char *cleanup_arg;
86 static char *opt_ff;
87 static char *opt_verify_signatures;
88 static char *opt_verify;
89 static int opt_autostash = -1;
90 static int config_autostash;
91 static int check_trust_level = 1;
92 static struct strvec opt_strategies = STRVEC_INIT;
93 static struct strvec opt_strategy_opts = STRVEC_INIT;
94 static char *opt_gpg_sign;
95 static int opt_allow_unrelated_histories;
96
97 /* Options passed to git-fetch */
98 static char *opt_all;
99 static char *opt_append;
100 static char *opt_upload_pack;
101 static int opt_force;
102 static char *opt_tags;
103 static char *opt_prune;
104 static char *max_children;
105 static int opt_dry_run;
106 static char *opt_keep;
107 static char *opt_depth;
108 static char *opt_unshallow;
109 static char *opt_update_shallow;
110 static char *opt_refmap;
111 static char *opt_ipv4;
112 static char *opt_ipv6;
113 static int opt_show_forced_updates = -1;
114 static char *set_upstream;
115 static struct strvec opt_fetch = STRVEC_INIT;
116
117 static struct option pull_options[] = {
118 /* Shared options */
119 OPT__VERBOSITY(&opt_verbosity),
120 OPT_PASSTHRU(0, "progress", &opt_progress, NULL,
121 N_("force progress reporting"),
122 PARSE_OPT_NOARG),
123 OPT_CALLBACK_F(0, "recurse-submodules",
124 &recurse_submodules_cli, N_("on-demand"),
125 N_("control for recursive fetching of submodules"),
126 PARSE_OPT_OPTARG, option_fetch_parse_recurse_submodules),
127
128 /* Options passed to git-merge or git-rebase */
129 OPT_GROUP(N_("Options related to merging")),
130 OPT_CALLBACK_F('r', "rebase", &opt_rebase,
131 "(false|true|merges|interactive)",
132 N_("incorporate changes by rebasing rather than merging"),
133 PARSE_OPT_OPTARG, parse_opt_rebase),
134 OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL,
135 N_("do not show a diffstat at the end of the merge"),
136 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
137 OPT_PASSTHRU(0, "stat", &opt_diffstat, NULL,
138 N_("show a diffstat at the end of the merge"),
139 PARSE_OPT_NOARG),
140 OPT_PASSTHRU(0, "summary", &opt_diffstat, NULL,
141 N_("(synonym to --stat)"),
142 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN),
143 OPT_PASSTHRU(0, "log", &opt_log, N_("n"),
144 N_("add (at most <n>) entries from shortlog to merge commit message"),
145 PARSE_OPT_OPTARG),
146 OPT_PASSTHRU(0, "signoff", &opt_signoff, NULL,
147 N_("add a Signed-off-by trailer"),
148 PARSE_OPT_OPTARG),
149 OPT_PASSTHRU(0, "squash", &opt_squash, NULL,
150 N_("create a single commit instead of doing a merge"),
151 PARSE_OPT_NOARG),
152 OPT_PASSTHRU(0, "commit", &opt_commit, NULL,
153 N_("perform a commit if the merge succeeds (default)"),
154 PARSE_OPT_NOARG),
155 OPT_PASSTHRU(0, "edit", &opt_edit, NULL,
156 N_("edit message before committing"),
157 PARSE_OPT_NOARG),
158 OPT_CLEANUP(&cleanup_arg),
159 OPT_PASSTHRU(0, "ff", &opt_ff, NULL,
160 N_("allow fast-forward"),
161 PARSE_OPT_NOARG),
162 OPT_PASSTHRU(0, "ff-only", &opt_ff, NULL,
163 N_("abort if fast-forward is not possible"),
164 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
165 OPT_PASSTHRU(0, "verify", &opt_verify, NULL,
166 N_("control use of pre-merge-commit and commit-msg hooks"),
167 PARSE_OPT_NOARG),
168 OPT_PASSTHRU(0, "verify-signatures", &opt_verify_signatures, NULL,
169 N_("verify that the named commit has a valid GPG signature"),
170 PARSE_OPT_NOARG),
171 OPT_BOOL(0, "autostash", &opt_autostash,
172 N_("automatically stash/stash pop before and after")),
173 OPT_PASSTHRU_ARGV('s', "strategy", &opt_strategies, N_("strategy"),
174 N_("merge strategy to use"),
175 0),
176 OPT_PASSTHRU_ARGV('X', "strategy-option", &opt_strategy_opts,
177 N_("option=value"),
178 N_("option for selected merge strategy"),
179 0),
180 OPT_PASSTHRU('S', "gpg-sign", &opt_gpg_sign, N_("key-id"),
181 N_("GPG sign commit"),
182 PARSE_OPT_OPTARG),
183 OPT_SET_INT(0, "allow-unrelated-histories",
184 &opt_allow_unrelated_histories,
185 N_("allow merging unrelated histories"), 1),
186
187 /* Options passed to git-fetch */
188 OPT_GROUP(N_("Options related to fetching")),
189 OPT_PASSTHRU(0, "all", &opt_all, NULL,
190 N_("fetch from all remotes"),
191 PARSE_OPT_NOARG),
192 OPT_PASSTHRU('a', "append", &opt_append, NULL,
193 N_("append to .git/FETCH_HEAD instead of overwriting"),
194 PARSE_OPT_NOARG),
195 OPT_PASSTHRU(0, "upload-pack", &opt_upload_pack, N_("path"),
196 N_("path to upload pack on remote end"),
197 0),
198 OPT__FORCE(&opt_force, N_("force overwrite of local branch"), 0),
199 OPT_PASSTHRU('t', "tags", &opt_tags, NULL,
200 N_("fetch all tags and associated objects"),
201 PARSE_OPT_NOARG),
202 OPT_PASSTHRU('p', "prune", &opt_prune, NULL,
203 N_("prune remote-tracking branches no longer on remote"),
204 PARSE_OPT_NOARG),
205 OPT_PASSTHRU('j', "jobs", &max_children, N_("n"),
206 N_("number of submodules pulled in parallel"),
207 PARSE_OPT_OPTARG),
208 OPT_BOOL(0, "dry-run", &opt_dry_run,
209 N_("dry run")),
210 OPT_PASSTHRU('k', "keep", &opt_keep, NULL,
211 N_("keep downloaded pack"),
212 PARSE_OPT_NOARG),
213 OPT_PASSTHRU(0, "depth", &opt_depth, N_("depth"),
214 N_("deepen history of shallow clone"),
215 0),
216 OPT_PASSTHRU_ARGV(0, "shallow-since", &opt_fetch, N_("time"),
217 N_("deepen history of shallow repository based on time"),
218 0),
219 OPT_PASSTHRU_ARGV(0, "shallow-exclude", &opt_fetch, N_("revision"),
220 N_("deepen history of shallow clone, excluding rev"),
221 0),
222 OPT_PASSTHRU_ARGV(0, "deepen", &opt_fetch, N_("n"),
223 N_("deepen history of shallow clone"),
224 0),
225 OPT_PASSTHRU(0, "unshallow", &opt_unshallow, NULL,
226 N_("convert to a complete repository"),
227 PARSE_OPT_NONEG | PARSE_OPT_NOARG),
228 OPT_PASSTHRU(0, "update-shallow", &opt_update_shallow, NULL,
229 N_("accept refs that update .git/shallow"),
230 PARSE_OPT_NOARG),
231 OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"),
232 N_("specify fetch refmap"),
233 PARSE_OPT_NONEG),
234 OPT_PASSTHRU_ARGV('o', "server-option", &opt_fetch,
235 N_("server-specific"),
236 N_("option to transmit"),
237 0),
238 OPT_PASSTHRU('4', "ipv4", &opt_ipv4, NULL,
239 N_("use IPv4 addresses only"),
240 PARSE_OPT_NOARG),
241 OPT_PASSTHRU('6', "ipv6", &opt_ipv6, NULL,
242 N_("use IPv6 addresses only"),
243 PARSE_OPT_NOARG),
244 OPT_PASSTHRU_ARGV(0, "negotiation-tip", &opt_fetch, N_("revision"),
245 N_("report that we have only objects reachable from this object"),
246 0),
247 OPT_BOOL(0, "show-forced-updates", &opt_show_forced_updates,
248 N_("check for forced-updates on all updated branches")),
249 OPT_PASSTHRU(0, "set-upstream", &set_upstream, NULL,
250 N_("set upstream for git pull/fetch"),
251 PARSE_OPT_NOARG),
252
253 OPT_END()
254 };
255
256 /**
257 * Pushes "-q" or "-v" switches into arr to match the opt_verbosity level.
258 */
259 static void argv_push_verbosity(struct strvec *arr)
260 {
261 int verbosity;
262
263 for (verbosity = opt_verbosity; verbosity > 0; verbosity--)
264 strvec_push(arr, "-v");
265
266 for (verbosity = opt_verbosity; verbosity < 0; verbosity++)
267 strvec_push(arr, "-q");
268 }
269
270 /**
271 * Pushes "-f" switches into arr to match the opt_force level.
272 */
273 static void argv_push_force(struct strvec *arr)
274 {
275 int force = opt_force;
276 while (force-- > 0)
277 strvec_push(arr, "-f");
278 }
279
280 /**
281 * Sets the GIT_REFLOG_ACTION environment variable to the concatenation of argv
282 */
283 static void set_reflog_message(int argc, const char **argv)
284 {
285 int i;
286 struct strbuf msg = STRBUF_INIT;
287
288 for (i = 0; i < argc; i++) {
289 if (i)
290 strbuf_addch(&msg, ' ');
291 strbuf_addstr(&msg, argv[i]);
292 }
293
294 setenv("GIT_REFLOG_ACTION", msg.buf, 0);
295
296 strbuf_release(&msg);
297 }
298
299 /**
300 * If pull.ff is unset, returns NULL. If pull.ff is "true", returns "--ff". If
301 * pull.ff is "false", returns "--no-ff". If pull.ff is "only", returns
302 * "--ff-only". Otherwise, if pull.ff is set to an invalid value, die with an
303 * error.
304 */
305 static const char *config_get_ff(void)
306 {
307 const char *value;
308
309 if (git_config_get_value("pull.ff", &value))
310 return NULL;
311
312 switch (git_parse_maybe_bool(value)) {
313 case 0:
314 return "--no-ff";
315 case 1:
316 return "--ff";
317 }
318
319 if (!strcmp(value, "only"))
320 return "--ff-only";
321
322 die(_("invalid value for '%s': '%s'"), "pull.ff", value);
323 }
324
325 /**
326 * Returns the default configured value for --rebase. It first looks for the
327 * value of "branch.$curr_branch.rebase", where $curr_branch is the current
328 * branch, and if HEAD is detached or the configuration key does not exist,
329 * looks for the value of "pull.rebase". If both configuration keys do not
330 * exist, returns REBASE_FALSE.
331 */
332 static enum rebase_type config_get_rebase(int *rebase_unspecified)
333 {
334 struct branch *curr_branch = branch_get("HEAD");
335 const char *value;
336
337 if (curr_branch) {
338 char *key = xstrfmt("branch.%s.rebase", curr_branch->name);
339
340 if (!git_config_get_value(key, &value)) {
341 enum rebase_type ret = parse_config_rebase(key, value, 1);
342 free(key);
343 return ret;
344 }
345
346 free(key);
347 }
348
349 if (!git_config_get_value("pull.rebase", &value))
350 return parse_config_rebase("pull.rebase", value, 1);
351
352 *rebase_unspecified = 1;
353
354 return REBASE_FALSE;
355 }
356
357 /**
358 * Read config variables.
359 */
360 static int git_pull_config(const char *var, const char *value, void *cb)
361 {
362 int status;
363
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;
373 }
374
375 status = git_gpg_config(var, value, cb);
376 if (status)
377 return status;
378
379 return git_default_config(var, value, cb);
380 }
381
382 /**
383 * Appends merge candidates from FETCH_HEAD that are not marked not-for-merge
384 * into merge_heads.
385 */
386 static void get_merge_heads(struct oid_array *merge_heads)
387 {
388 const char *filename = git_path_fetch_head(the_repository);
389 FILE *fp;
390 struct strbuf sb = STRBUF_INIT;
391 struct object_id oid;
392
393 fp = xfopen(filename, "r");
394 while (strbuf_getline_lf(&sb, fp) != EOF) {
395 const char *p;
396 if (parse_oid_hex(sb.buf, &oid, &p))
397 continue; /* invalid line: does not start with object ID */
398 if (starts_with(p, "\tnot-for-merge\t"))
399 continue; /* ref is not-for-merge */
400 oid_array_append(merge_heads, &oid);
401 }
402 fclose(fp);
403 strbuf_release(&sb);
404 }
405
406 /**
407 * Used by die_no_merge_candidates() as a for_each_remote() callback to
408 * retrieve the name of the remote if the repository only has one remote.
409 */
410 static int get_only_remote(struct remote *remote, void *cb_data)
411 {
412 const char **remote_name = cb_data;
413
414 if (*remote_name)
415 return -1;
416
417 *remote_name = remote->name;
418 return 0;
419 }
420
421 /**
422 * Dies with the appropriate reason for why there are no merge candidates:
423 *
424 * 1. We fetched from a specific remote, and a refspec was given, but it ended
425 * up not fetching anything. This is usually because the user provided a
426 * wildcard refspec which had no matches on the remote end.
427 *
428 * 2. We fetched from a non-default remote, but didn't specify a branch to
429 * merge. We can't use the configured one because it applies to the default
430 * remote, thus the user must specify the branches to merge.
431 *
432 * 3. We fetched from the branch's or repo's default remote, but:
433 *
434 * a. We are not on a branch, so there will never be a configured branch to
435 * merge with.
436 *
437 * b. We are on a branch, but there is no configured branch to merge with.
438 *
439 * 4. We fetched from the branch's or repo's default remote, but the configured
440 * branch to merge didn't get fetched. (Either it doesn't exist, or wasn't
441 * part of the configured fetch refspec.)
442 */
443 static void NORETURN die_no_merge_candidates(const char *repo, const char **refspecs)
444 {
445 struct branch *curr_branch = branch_get("HEAD");
446 const char *remote = curr_branch ? curr_branch->remote_name : NULL;
447
448 if (*refspecs) {
449 if (opt_rebase)
450 fprintf_ln(stderr, _("There is no candidate for rebasing against among the refs that you just fetched."));
451 else
452 fprintf_ln(stderr, _("There are no candidates for merging among the refs that you just fetched."));
453 fprintf_ln(stderr, _("Generally this means that you provided a wildcard refspec which had no\n"
454 "matches on the remote end."));
455 } else if (repo && curr_branch && (!remote || strcmp(repo, remote))) {
456 fprintf_ln(stderr, _("You asked to pull from the remote '%s', but did not specify\n"
457 "a branch. Because this is not the default configured remote\n"
458 "for your current branch, you must specify a branch on the command line."),
459 repo);
460 } else if (!curr_branch) {
461 fprintf_ln(stderr, _("You are not currently on a branch."));
462 if (opt_rebase)
463 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
464 else
465 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
466 fprintf_ln(stderr, _("See git-pull(1) for details."));
467 fprintf(stderr, "\n");
468 fprintf_ln(stderr, " git pull %s %s", _("<remote>"), _("<branch>"));
469 fprintf(stderr, "\n");
470 } else if (!curr_branch->merge_nr) {
471 const char *remote_name = NULL;
472
473 if (for_each_remote(get_only_remote, &remote_name) || !remote_name)
474 remote_name = _("<remote>");
475
476 fprintf_ln(stderr, _("There is no tracking information for the current branch."));
477 if (opt_rebase)
478 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
479 else
480 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
481 fprintf_ln(stderr, _("See git-pull(1) for details."));
482 fprintf(stderr, "\n");
483 fprintf_ln(stderr, " git pull %s %s", _("<remote>"), _("<branch>"));
484 fprintf(stderr, "\n");
485 fprintf_ln(stderr, _("If you wish to set tracking information for this branch you can do so with:"));
486 fprintf(stderr, "\n");
487 fprintf_ln(stderr, " git branch --set-upstream-to=%s/%s %s\n",
488 remote_name, _("<branch>"), curr_branch->name);
489 } else
490 fprintf_ln(stderr, _("Your configuration specifies to merge with the ref '%s'\n"
491 "from the remote, but no such ref was fetched."),
492 *curr_branch->merge_name);
493 exit(1);
494 }
495
496 /**
497 * Parses argv into [<repo> [<refspecs>...]], returning their values in `repo`
498 * as a string and `refspecs` as a null-terminated array of strings. If `repo`
499 * is not provided in argv, it is set to NULL.
500 */
501 static void parse_repo_refspecs(int argc, const char **argv, const char **repo,
502 const char ***refspecs)
503 {
504 if (argc > 0) {
505 *repo = *argv++;
506 argc--;
507 } else
508 *repo = NULL;
509 *refspecs = argv;
510 }
511
512 /**
513 * Runs git-fetch, returning its exit status. `repo` and `refspecs` are the
514 * repository and refspecs to fetch, or NULL if they are not provided.
515 */
516 static int run_fetch(const char *repo, const char **refspecs)
517 {
518 struct strvec args = STRVEC_INIT;
519 int ret;
520
521 strvec_pushl(&args, "fetch", "--update-head-ok", NULL);
522
523 /* Shared options */
524 argv_push_verbosity(&args);
525 if (opt_progress)
526 strvec_push(&args, opt_progress);
527
528 /* Options passed to git-fetch */
529 if (opt_all)
530 strvec_push(&args, opt_all);
531 if (opt_append)
532 strvec_push(&args, opt_append);
533 if (opt_upload_pack)
534 strvec_push(&args, opt_upload_pack);
535 argv_push_force(&args);
536 if (opt_tags)
537 strvec_push(&args, opt_tags);
538 if (opt_prune)
539 strvec_push(&args, opt_prune);
540 if (recurse_submodules_cli != RECURSE_SUBMODULES_DEFAULT)
541 switch (recurse_submodules_cli) {
542 case RECURSE_SUBMODULES_ON:
543 strvec_push(&args, "--recurse-submodules=on");
544 break;
545 case RECURSE_SUBMODULES_OFF:
546 strvec_push(&args, "--recurse-submodules=no");
547 break;
548 case RECURSE_SUBMODULES_ON_DEMAND:
549 strvec_push(&args, "--recurse-submodules=on-demand");
550 break;
551 default:
552 BUG("submodule recursion option not understood");
553 }
554 if (max_children)
555 strvec_push(&args, max_children);
556 if (opt_dry_run)
557 strvec_push(&args, "--dry-run");
558 if (opt_keep)
559 strvec_push(&args, opt_keep);
560 if (opt_depth)
561 strvec_push(&args, opt_depth);
562 if (opt_unshallow)
563 strvec_push(&args, opt_unshallow);
564 if (opt_update_shallow)
565 strvec_push(&args, opt_update_shallow);
566 if (opt_refmap)
567 strvec_push(&args, opt_refmap);
568 if (opt_ipv4)
569 strvec_push(&args, opt_ipv4);
570 if (opt_ipv6)
571 strvec_push(&args, opt_ipv6);
572 if (opt_show_forced_updates > 0)
573 strvec_push(&args, "--show-forced-updates");
574 else if (opt_show_forced_updates == 0)
575 strvec_push(&args, "--no-show-forced-updates");
576 if (set_upstream)
577 strvec_push(&args, set_upstream);
578 strvec_pushv(&args, opt_fetch.v);
579
580 if (repo) {
581 strvec_push(&args, repo);
582 strvec_pushv(&args, refspecs);
583 } else if (*refspecs)
584 BUG("refspecs without repo?");
585 ret = run_command_v_opt(args.v, RUN_GIT_CMD | RUN_CLOSE_OBJECT_STORE);
586 strvec_clear(&args);
587 return ret;
588 }
589
590 /**
591 * "Pulls into void" by branching off merge_head.
592 */
593 static int pull_into_void(const struct object_id *merge_head,
594 const struct object_id *curr_head)
595 {
596 if (opt_verify_signatures) {
597 struct commit *commit;
598
599 commit = lookup_commit(the_repository, merge_head);
600 if (!commit)
601 die(_("unable to access commit %s"),
602 oid_to_hex(merge_head));
603
604 verify_merge_signature(commit, opt_verbosity,
605 check_trust_level);
606 }
607
608 /*
609 * Two-way merge: we treat the index as based on an empty tree,
610 * and try to fast-forward to HEAD. This ensures we will not lose
611 * index/worktree changes that the user already made on the unborn
612 * branch.
613 */
614 if (checkout_fast_forward(the_repository,
615 the_hash_algo->empty_tree,
616 merge_head, 0))
617 return 1;
618
619 if (update_ref("initial pull", "HEAD", merge_head, curr_head, 0, UPDATE_REFS_DIE_ON_ERR))
620 return 1;
621
622 return 0;
623 }
624
625 static int rebase_submodules(void)
626 {
627 struct child_process cp = CHILD_PROCESS_INIT;
628
629 cp.git_cmd = 1;
630 cp.no_stdin = 1;
631 strvec_pushl(&cp.args, "submodule", "update",
632 "--recursive", "--rebase", NULL);
633 argv_push_verbosity(&cp.args);
634
635 return run_command(&cp);
636 }
637
638 static int update_submodules(void)
639 {
640 struct child_process cp = CHILD_PROCESS_INIT;
641
642 cp.git_cmd = 1;
643 cp.no_stdin = 1;
644 strvec_pushl(&cp.args, "submodule", "update",
645 "--recursive", "--checkout", NULL);
646 argv_push_verbosity(&cp.args);
647
648 return run_command(&cp);
649 }
650
651 /**
652 * Runs git-merge, returning its exit status.
653 */
654 static int run_merge(void)
655 {
656 int ret;
657 struct strvec args = STRVEC_INIT;
658
659 strvec_pushl(&args, "merge", NULL);
660
661 /* Shared options */
662 argv_push_verbosity(&args);
663 if (opt_progress)
664 strvec_push(&args, opt_progress);
665
666 /* Options passed to git-merge */
667 if (opt_diffstat)
668 strvec_push(&args, opt_diffstat);
669 if (opt_log)
670 strvec_push(&args, opt_log);
671 if (opt_signoff)
672 strvec_push(&args, opt_signoff);
673 if (opt_squash)
674 strvec_push(&args, opt_squash);
675 if (opt_commit)
676 strvec_push(&args, opt_commit);
677 if (opt_edit)
678 strvec_push(&args, opt_edit);
679 if (cleanup_arg)
680 strvec_pushf(&args, "--cleanup=%s", cleanup_arg);
681 if (opt_ff)
682 strvec_push(&args, opt_ff);
683 if (opt_verify)
684 strvec_push(&args, opt_verify);
685 if (opt_verify_signatures)
686 strvec_push(&args, opt_verify_signatures);
687 strvec_pushv(&args, opt_strategies.v);
688 strvec_pushv(&args, opt_strategy_opts.v);
689 if (opt_gpg_sign)
690 strvec_push(&args, opt_gpg_sign);
691 if (opt_autostash == 0)
692 strvec_push(&args, "--no-autostash");
693 else if (opt_autostash == 1)
694 strvec_push(&args, "--autostash");
695 if (opt_allow_unrelated_histories > 0)
696 strvec_push(&args, "--allow-unrelated-histories");
697
698 strvec_push(&args, "FETCH_HEAD");
699 ret = run_command_v_opt(args.v, RUN_GIT_CMD);
700 strvec_clear(&args);
701 return ret;
702 }
703
704 /**
705 * Returns remote's upstream branch for the current branch. If remote is NULL,
706 * the current branch's configured default remote is used. Returns NULL if
707 * `remote` does not name a valid remote, HEAD does not point to a branch,
708 * remote is not the branch's configured remote or the branch does not have any
709 * configured upstream branch.
710 */
711 static const char *get_upstream_branch(const char *remote)
712 {
713 struct remote *rm;
714 struct branch *curr_branch;
715 const char *curr_branch_remote;
716
717 rm = remote_get(remote);
718 if (!rm)
719 return NULL;
720
721 curr_branch = branch_get("HEAD");
722 if (!curr_branch)
723 return NULL;
724
725 curr_branch_remote = remote_for_branch(curr_branch, NULL);
726 assert(curr_branch_remote);
727
728 if (strcmp(curr_branch_remote, rm->name))
729 return NULL;
730
731 return branch_get_upstream(curr_branch, NULL);
732 }
733
734 /**
735 * Derives the remote-tracking branch from the remote and refspec.
736 *
737 * FIXME: The current implementation assumes the default mapping of
738 * refs/heads/<branch_name> to refs/remotes/<remote_name>/<branch_name>.
739 */
740 static const char *get_tracking_branch(const char *remote, const char *refspec)
741 {
742 struct refspec_item spec;
743 const char *spec_src;
744 const char *merge_branch;
745
746 refspec_item_init_or_die(&spec, refspec, REFSPEC_FETCH);
747 spec_src = spec.src;
748 if (!*spec_src || !strcmp(spec_src, "HEAD"))
749 spec_src = "HEAD";
750 else if (skip_prefix(spec_src, "heads/", &spec_src))
751 ;
752 else if (skip_prefix(spec_src, "refs/heads/", &spec_src))
753 ;
754 else if (starts_with(spec_src, "refs/") ||
755 starts_with(spec_src, "tags/") ||
756 starts_with(spec_src, "remotes/"))
757 spec_src = "";
758
759 if (*spec_src) {
760 if (!strcmp(remote, "."))
761 merge_branch = mkpath("refs/heads/%s", spec_src);
762 else
763 merge_branch = mkpath("refs/remotes/%s/%s", remote, spec_src);
764 } else
765 merge_branch = NULL;
766
767 refspec_item_clear(&spec);
768 return merge_branch;
769 }
770
771 /**
772 * Given the repo and refspecs, sets fork_point to the point at which the
773 * current branch forked from its remote-tracking branch. Returns 0 on success,
774 * -1 on failure.
775 */
776 static int get_rebase_fork_point(struct object_id *fork_point, const char *repo,
777 const char *refspec)
778 {
779 int ret;
780 struct branch *curr_branch;
781 const char *remote_branch;
782 struct child_process cp = CHILD_PROCESS_INIT;
783 struct strbuf sb = STRBUF_INIT;
784
785 curr_branch = branch_get("HEAD");
786 if (!curr_branch)
787 return -1;
788
789 if (refspec)
790 remote_branch = get_tracking_branch(repo, refspec);
791 else
792 remote_branch = get_upstream_branch(repo);
793
794 if (!remote_branch)
795 return -1;
796
797 strvec_pushl(&cp.args, "merge-base", "--fork-point",
798 remote_branch, curr_branch->name, NULL);
799 cp.no_stdin = 1;
800 cp.no_stderr = 1;
801 cp.git_cmd = 1;
802
803 ret = capture_command(&cp, &sb, GIT_MAX_HEXSZ);
804 if (ret)
805 goto cleanup;
806
807 ret = get_oid_hex(sb.buf, fork_point);
808 if (ret)
809 goto cleanup;
810
811 cleanup:
812 strbuf_release(&sb);
813 return ret ? -1 : 0;
814 }
815
816 /**
817 * Sets merge_base to the octopus merge base of curr_head, merge_head and
818 * fork_point. Returns 0 if a merge base is found, 1 otherwise.
819 */
820 static int get_octopus_merge_base(struct object_id *merge_base,
821 const struct object_id *curr_head,
822 const struct object_id *merge_head,
823 const struct object_id *fork_point)
824 {
825 struct commit_list *revs = NULL, *result;
826
827 commit_list_insert(lookup_commit_reference(the_repository, curr_head),
828 &revs);
829 commit_list_insert(lookup_commit_reference(the_repository, merge_head),
830 &revs);
831 if (!is_null_oid(fork_point))
832 commit_list_insert(lookup_commit_reference(the_repository, fork_point),
833 &revs);
834
835 result = get_octopus_merge_bases(revs);
836 free_commit_list(revs);
837 reduce_heads_replace(&result);
838
839 if (!result)
840 return 1;
841
842 oidcpy(merge_base, &result->item->object.oid);
843 free_commit_list(result);
844 return 0;
845 }
846
847 /**
848 * Given the current HEAD oid, the merge head returned from git-fetch and the
849 * fork point calculated by get_rebase_fork_point(), compute the <newbase> and
850 * <upstream> arguments to use for the upcoming git-rebase invocation.
851 */
852 static int get_rebase_newbase_and_upstream(struct object_id *newbase,
853 struct object_id *upstream,
854 const struct object_id *curr_head,
855 const struct object_id *merge_head,
856 const struct object_id *fork_point)
857 {
858 struct object_id oct_merge_base;
859
860 if (!get_octopus_merge_base(&oct_merge_base, curr_head, merge_head, fork_point))
861 if (!is_null_oid(fork_point) && oideq(&oct_merge_base, fork_point))
862 fork_point = NULL;
863
864 if (fork_point && !is_null_oid(fork_point))
865 oidcpy(upstream, fork_point);
866 else
867 oidcpy(upstream, merge_head);
868
869 oidcpy(newbase, merge_head);
870
871 return 0;
872 }
873
874 /**
875 * Given the <newbase> and <upstream> calculated by
876 * get_rebase_newbase_and_upstream(), runs git-rebase with the
877 * appropriate arguments and returns its exit status.
878 */
879 static int run_rebase(const struct object_id *newbase,
880 const struct object_id *upstream)
881 {
882 int ret;
883 struct strvec args = STRVEC_INIT;
884
885 strvec_push(&args, "rebase");
886
887 /* Shared options */
888 argv_push_verbosity(&args);
889
890 /* Options passed to git-rebase */
891 if (opt_rebase == REBASE_MERGES)
892 strvec_push(&args, "--rebase-merges");
893 else if (opt_rebase == REBASE_INTERACTIVE)
894 strvec_push(&args, "--interactive");
895 if (opt_diffstat)
896 strvec_push(&args, opt_diffstat);
897 strvec_pushv(&args, opt_strategies.v);
898 strvec_pushv(&args, opt_strategy_opts.v);
899 if (opt_gpg_sign)
900 strvec_push(&args, opt_gpg_sign);
901 if (opt_signoff)
902 strvec_push(&args, opt_signoff);
903 if (opt_autostash == 0)
904 strvec_push(&args, "--no-autostash");
905 else if (opt_autostash == 1)
906 strvec_push(&args, "--autostash");
907 if (opt_verify_signatures &&
908 !strcmp(opt_verify_signatures, "--verify-signatures"))
909 warning(_("ignoring --verify-signatures for rebase"));
910
911 strvec_push(&args, "--onto");
912 strvec_push(&args, oid_to_hex(newbase));
913
914 strvec_push(&args, oid_to_hex(upstream));
915
916 ret = run_command_v_opt(args.v, RUN_GIT_CMD);
917 strvec_clear(&args);
918 return ret;
919 }
920
921 static int get_can_ff(struct object_id *orig_head,
922 struct oid_array *merge_heads)
923 {
924 int ret;
925 struct commit_list *list = NULL;
926 struct commit *merge_head, *head;
927 struct object_id *orig_merge_head;
928
929 if (merge_heads->nr > 1)
930 return 0;
931
932 orig_merge_head = &merge_heads->oid[0];
933 head = lookup_commit_reference(the_repository, orig_head);
934 commit_list_insert(head, &list);
935 merge_head = lookup_commit_reference(the_repository, orig_merge_head);
936 ret = repo_is_descendant_of(the_repository, merge_head, list);
937 free_commit_list(list);
938 return ret;
939 }
940
941 /*
942 * Is orig_head a descendant of _all_ merge_heads?
943 * Unfortunately is_descendant_of() cannot be used as it asks
944 * if orig_head is a descendant of at least one of them.
945 */
946 static int already_up_to_date(struct object_id *orig_head,
947 struct oid_array *merge_heads)
948 {
949 int i;
950 struct commit *ours;
951
952 ours = lookup_commit_reference(the_repository, orig_head);
953 for (i = 0; i < merge_heads->nr; i++) {
954 struct commit_list *list = NULL;
955 struct commit *theirs;
956 int ok;
957
958 theirs = lookup_commit_reference(the_repository, &merge_heads->oid[i]);
959 commit_list_insert(theirs, &list);
960 ok = repo_is_descendant_of(the_repository, ours, list);
961 free_commit_list(list);
962 if (!ok)
963 return 0;
964 }
965 return 1;
966 }
967
968 static void show_advice_pull_non_ff(void)
969 {
970 advise(_("You have divergent branches and need to specify how to reconcile them.\n"
971 "You can do so by running one of the following commands sometime before\n"
972 "your next pull:\n"
973 "\n"
974 " git config pull.rebase false # merge\n"
975 " git config pull.rebase true # rebase\n"
976 " git config pull.ff only # fast-forward only\n"
977 "\n"
978 "You can replace \"git config\" with \"git config --global\" to set a default\n"
979 "preference for all repositories. You can also pass --rebase, --no-rebase,\n"
980 "or --ff-only on the command line to override the configured default per\n"
981 "invocation.\n"));
982 }
983
984 int cmd_pull(int argc, const char **argv, const char *prefix)
985 {
986 const char *repo, **refspecs;
987 struct oid_array merge_heads = OID_ARRAY_INIT;
988 struct object_id orig_head, curr_head;
989 struct object_id rebase_fork_point;
990 int rebase_unspecified = 0;
991 int can_ff;
992 int divergent;
993 int ret;
994
995 if (!getenv("GIT_REFLOG_ACTION"))
996 set_reflog_message(argc, argv);
997
998 git_config(git_pull_config, NULL);
999 if (the_repository->gitdir) {
1000 prepare_repo_settings(the_repository);
1001 the_repository->settings.command_requires_full_index = 0;
1002 }
1003
1004 argc = parse_options(argc, argv, prefix, pull_options, pull_usage, 0);
1005
1006 if (recurse_submodules_cli != RECURSE_SUBMODULES_DEFAULT)
1007 recurse_submodules = recurse_submodules_cli;
1008
1009 if (cleanup_arg)
1010 /*
1011 * this only checks the validity of cleanup_arg; we don't need
1012 * a valid value for use_editor
1013 */
1014 get_cleanup_mode(cleanup_arg, 0);
1015
1016 parse_repo_refspecs(argc, argv, &repo, &refspecs);
1017
1018 if (!opt_ff) {
1019 opt_ff = xstrdup_or_null(config_get_ff());
1020 /*
1021 * A subtle point: opt_ff was set on the line above via
1022 * reading from config. opt_rebase, in contrast, is set
1023 * before this point via command line options. The setting
1024 * of opt_rebase via reading from config (using
1025 * config_get_rebase()) does not happen until later. We
1026 * are relying on the next if-condition happening before
1027 * the config_get_rebase() call so that an explicit
1028 * "--rebase" can override a config setting of
1029 * pull.ff=only.
1030 */
1031 if (opt_rebase >= 0 && opt_ff && !strcmp(opt_ff, "--ff-only"))
1032 opt_ff = "--ff";
1033 }
1034
1035 if (opt_rebase < 0)
1036 opt_rebase = config_get_rebase(&rebase_unspecified);
1037
1038 if (read_cache_unmerged())
1039 die_resolve_conflict("pull");
1040
1041 if (file_exists(git_path_merge_head(the_repository)))
1042 die_conclude_merge();
1043
1044 if (get_oid("HEAD", &orig_head))
1045 oidclr(&orig_head);
1046
1047 if (opt_rebase) {
1048 if (opt_autostash == -1)
1049 opt_autostash = config_autostash;
1050
1051 if (is_null_oid(&orig_head) && !is_cache_unborn())
1052 die(_("Updating an unborn branch with changes added to the index."));
1053
1054 if (!opt_autostash)
1055 require_clean_work_tree(the_repository,
1056 N_("pull with rebase"),
1057 _("please commit or stash them."), 1, 0);
1058
1059 if (get_rebase_fork_point(&rebase_fork_point, repo, *refspecs))
1060 oidclr(&rebase_fork_point);
1061 }
1062
1063 if (run_fetch(repo, refspecs))
1064 return 1;
1065
1066 if (opt_dry_run)
1067 return 0;
1068
1069 if (get_oid("HEAD", &curr_head))
1070 oidclr(&curr_head);
1071
1072 if (!is_null_oid(&orig_head) && !is_null_oid(&curr_head) &&
1073 !oideq(&orig_head, &curr_head)) {
1074 /*
1075 * The fetch involved updating the current branch.
1076 *
1077 * The working tree and the index file are still based on
1078 * orig_head commit, but we are merging into curr_head.
1079 * Update the working tree to match curr_head.
1080 */
1081
1082 warning(_("fetch updated the current branch head.\n"
1083 "fast-forwarding your working tree from\n"
1084 "commit %s."), oid_to_hex(&orig_head));
1085
1086 if (checkout_fast_forward(the_repository, &orig_head,
1087 &curr_head, 0))
1088 die(_("Cannot fast-forward your working tree.\n"
1089 "After making sure that you saved anything precious from\n"
1090 "$ git diff %s\n"
1091 "output, run\n"
1092 "$ git reset --hard\n"
1093 "to recover."), oid_to_hex(&orig_head));
1094 }
1095
1096 get_merge_heads(&merge_heads);
1097
1098 if (!merge_heads.nr)
1099 die_no_merge_candidates(repo, refspecs);
1100
1101 if (is_null_oid(&orig_head)) {
1102 if (merge_heads.nr > 1)
1103 die(_("Cannot merge multiple branches into empty head."));
1104 ret = pull_into_void(merge_heads.oid, &curr_head);
1105 goto cleanup;
1106 }
1107 if (merge_heads.nr > 1) {
1108 if (opt_rebase)
1109 die(_("Cannot rebase onto multiple branches."));
1110 if (opt_ff && !strcmp(opt_ff, "--ff-only"))
1111 die(_("Cannot fast-forward to multiple branches."));
1112 }
1113
1114 can_ff = get_can_ff(&orig_head, &merge_heads);
1115 divergent = !can_ff && !already_up_to_date(&orig_head, &merge_heads);
1116
1117 /* ff-only takes precedence over rebase */
1118 if (opt_ff && !strcmp(opt_ff, "--ff-only")) {
1119 if (divergent)
1120 die_ff_impossible();
1121 opt_rebase = REBASE_FALSE;
1122 }
1123 /* If no action specified and we can't fast forward, then warn. */
1124 if (!opt_ff && rebase_unspecified && divergent) {
1125 show_advice_pull_non_ff();
1126 die(_("Need to specify how to reconcile divergent branches."));
1127 }
1128
1129 if (opt_rebase) {
1130 struct object_id newbase;
1131 struct object_id upstream;
1132 get_rebase_newbase_and_upstream(&newbase, &upstream, &curr_head,
1133 merge_heads.oid, &rebase_fork_point);
1134
1135 if ((recurse_submodules == RECURSE_SUBMODULES_ON ||
1136 recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) &&
1137 submodule_touches_in_range(the_repository, &upstream, &curr_head))
1138 die(_("cannot rebase with locally recorded submodule modifications"));
1139
1140 if (can_ff) {
1141 /* we can fast-forward this without invoking rebase */
1142 opt_ff = "--ff-only";
1143 ret = run_merge();
1144 } else {
1145 ret = run_rebase(&newbase, &upstream);
1146 }
1147
1148 if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON ||
1149 recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND))
1150 ret = rebase_submodules();
1151
1152 goto cleanup;
1153 } else {
1154 ret = run_merge();
1155 if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON ||
1156 recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND))
1157 ret = update_submodules();
1158 goto cleanup;
1159 }
1160
1161 cleanup:
1162 oid_array_clear(&merge_heads);
1163 return ret;
1164 }