pull --rebase: exit early when the working directory is dirty
[git/git.git] / builtin / pull.c
CommitLineData
1e1ea69f
PT
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"
f2c5baa1 12#include "run-command.h"
44c175c7
PT
13#include "sha1-array.h"
14#include "remote.h"
4a4cf9e8 15#include "dir.h"
49ec402d 16#include "refs.h"
8944969c
PT
17#include "revision.h"
18#include "lockfile.h"
1e1ea69f 19
1678b81e
PT
20enum rebase_type {
21 REBASE_INVALID = -1,
22 REBASE_FALSE = 0,
23 REBASE_TRUE,
24 REBASE_PRESERVE
25};
26
27/**
28 * Parses the value of --rebase. If value is a false value, returns
29 * REBASE_FALSE. If value is a true value, returns REBASE_TRUE. If value is
30 * "preserve", returns REBASE_PRESERVE. If value is a invalid value, dies with
31 * a fatal error if fatal is true, otherwise returns REBASE_INVALID.
32 */
33static enum rebase_type parse_config_rebase(const char *key, const char *value,
34 int fatal)
35{
36 int v = git_config_maybe_bool("pull.rebase", value);
37
38 if (!v)
39 return REBASE_FALSE;
40 else if (v > 0)
41 return REBASE_TRUE;
42 else if (!strcmp(value, "preserve"))
43 return REBASE_PRESERVE;
44
45 if (fatal)
46 die(_("Invalid value for %s: %s"), key, value);
47 else
48 error(_("Invalid value for %s: %s"), key, value);
49
50 return REBASE_INVALID;
51}
52
53/**
54 * Callback for --rebase, which parses arg with parse_config_rebase().
55 */
56static int parse_opt_rebase(const struct option *opt, const char *arg, int unset)
57{
58 enum rebase_type *value = opt->value;
59
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;
65}
66
1e1ea69f 67static const char * const pull_usage[] = {
f2c5baa1 68 N_("git pull [options] [<repository> [<refspec>...]]"),
1e1ea69f
PT
69 NULL
70};
71
2a747902
PT
72/* Shared options */
73static int opt_verbosity;
74static char *opt_progress;
75
1678b81e 76/* Options passed to git-merge or git-rebase */
81dbd768 77static enum rebase_type opt_rebase = -1;
11b6d178
PT
78static char *opt_diffstat;
79static char *opt_log;
80static char *opt_squash;
81static char *opt_commit;
82static char *opt_edit;
83static char *opt_ff;
84static char *opt_verify_signatures;
85static struct argv_array opt_strategies = ARGV_ARRAY_INIT;
86static struct argv_array opt_strategy_opts = ARGV_ARRAY_INIT;
87static char *opt_gpg_sign;
88
a32975f5
PT
89/* Options passed to git-fetch */
90static char *opt_all;
91static char *opt_append;
92static char *opt_upload_pack;
93static int opt_force;
94static char *opt_tags;
95static char *opt_prune;
96static char *opt_recurse_submodules;
97static int opt_dry_run;
98static char *opt_keep;
99static char *opt_depth;
100static char *opt_unshallow;
101static char *opt_update_shallow;
102static char *opt_refmap;
103
1e1ea69f 104static struct option pull_options[] = {
2a747902
PT
105 /* Shared options */
106 OPT__VERBOSITY(&opt_verbosity),
107 OPT_PASSTHRU(0, "progress", &opt_progress, NULL,
108 N_("force progress reporting"),
109 PARSE_OPT_NOARG),
110
1678b81e 111 /* Options passed to git-merge or git-rebase */
11b6d178 112 OPT_GROUP(N_("Options related to merging")),
1678b81e
PT
113 { OPTION_CALLBACK, 'r', "rebase", &opt_rebase,
114 N_("false|true|preserve"),
115 N_("incorporate changes by rebasing rather than merging"),
116 PARSE_OPT_OPTARG, parse_opt_rebase },
11b6d178
PT
117 OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL,
118 N_("do not show a diffstat at the end of the merge"),
119 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
120 OPT_PASSTHRU(0, "stat", &opt_diffstat, NULL,
121 N_("show a diffstat at the end of the merge"),
122 PARSE_OPT_NOARG),
123 OPT_PASSTHRU(0, "summary", &opt_diffstat, NULL,
124 N_("(synonym to --stat)"),
125 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN),
126 OPT_PASSTHRU(0, "log", &opt_log, N_("n"),
127 N_("add (at most <n>) entries from shortlog to merge commit message"),
128 PARSE_OPT_OPTARG),
129 OPT_PASSTHRU(0, "squash", &opt_squash, NULL,
130 N_("create a single commit instead of doing a merge"),
131 PARSE_OPT_NOARG),
132 OPT_PASSTHRU(0, "commit", &opt_commit, NULL,
133 N_("perform a commit if the merge succeeds (default)"),
134 PARSE_OPT_NOARG),
135 OPT_PASSTHRU(0, "edit", &opt_edit, NULL,
136 N_("edit message before committing"),
137 PARSE_OPT_NOARG),
138 OPT_PASSTHRU(0, "ff", &opt_ff, NULL,
139 N_("allow fast-forward"),
140 PARSE_OPT_NOARG),
141 OPT_PASSTHRU(0, "ff-only", &opt_ff, NULL,
142 N_("abort if fast-forward is not possible"),
143 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
144 OPT_PASSTHRU(0, "verify-signatures", &opt_verify_signatures, NULL,
145 N_("verify that the named commit has a valid GPG signature"),
146 PARSE_OPT_NOARG),
147 OPT_PASSTHRU_ARGV('s', "strategy", &opt_strategies, N_("strategy"),
148 N_("merge strategy to use"),
149 0),
150 OPT_PASSTHRU_ARGV('X', "strategy-option", &opt_strategy_opts,
151 N_("option=value"),
152 N_("option for selected merge strategy"),
153 0),
154 OPT_PASSTHRU('S', "gpg-sign", &opt_gpg_sign, N_("key-id"),
155 N_("GPG sign commit"),
156 PARSE_OPT_OPTARG),
157
a32975f5
PT
158 /* Options passed to git-fetch */
159 OPT_GROUP(N_("Options related to fetching")),
160 OPT_PASSTHRU(0, "all", &opt_all, NULL,
161 N_("fetch from all remotes"),
162 PARSE_OPT_NOARG),
163 OPT_PASSTHRU('a', "append", &opt_append, NULL,
164 N_("append to .git/FETCH_HEAD instead of overwriting"),
165 PARSE_OPT_NOARG),
166 OPT_PASSTHRU(0, "upload-pack", &opt_upload_pack, N_("path"),
167 N_("path to upload pack on remote end"),
168 0),
169 OPT__FORCE(&opt_force, N_("force overwrite of local branch")),
170 OPT_PASSTHRU('t', "tags", &opt_tags, NULL,
171 N_("fetch all tags and associated objects"),
172 PARSE_OPT_NOARG),
173 OPT_PASSTHRU('p', "prune", &opt_prune, NULL,
174 N_("prune remote-tracking branches no longer on remote"),
175 PARSE_OPT_NOARG),
176 OPT_PASSTHRU(0, "recurse-submodules", &opt_recurse_submodules,
177 N_("on-demand"),
178 N_("control recursive fetching of submodules"),
179 PARSE_OPT_OPTARG),
180 OPT_BOOL(0, "dry-run", &opt_dry_run,
181 N_("dry run")),
182 OPT_PASSTHRU('k', "keep", &opt_keep, NULL,
183 N_("keep downloaded pack"),
184 PARSE_OPT_NOARG),
185 OPT_PASSTHRU(0, "depth", &opt_depth, N_("depth"),
186 N_("deepen history of shallow clone"),
187 0),
188 OPT_PASSTHRU(0, "unshallow", &opt_unshallow, NULL,
189 N_("convert to a complete repository"),
190 PARSE_OPT_NONEG | PARSE_OPT_NOARG),
191 OPT_PASSTHRU(0, "update-shallow", &opt_update_shallow, NULL,
192 N_("accept refs that update .git/shallow"),
193 PARSE_OPT_NOARG),
194 OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"),
195 N_("specify fetch refmap"),
196 PARSE_OPT_NONEG),
197
1e1ea69f
PT
198 OPT_END()
199};
200
2a747902
PT
201/**
202 * Pushes "-q" or "-v" switches into arr to match the opt_verbosity level.
203 */
204static void argv_push_verbosity(struct argv_array *arr)
205{
206 int verbosity;
207
208 for (verbosity = opt_verbosity; verbosity > 0; verbosity--)
209 argv_array_push(arr, "-v");
210
211 for (verbosity = opt_verbosity; verbosity < 0; verbosity++)
212 argv_array_push(arr, "-q");
213}
214
a32975f5
PT
215/**
216 * Pushes "-f" switches into arr to match the opt_force level.
217 */
218static void argv_push_force(struct argv_array *arr)
219{
220 int force = opt_force;
221 while (force-- > 0)
222 argv_array_push(arr, "-f");
223}
224
41fca098
PT
225/**
226 * Sets the GIT_REFLOG_ACTION environment variable to the concatenation of argv
227 */
228static void set_reflog_message(int argc, const char **argv)
229{
230 int i;
231 struct strbuf msg = STRBUF_INIT;
232
233 for (i = 0; i < argc; i++) {
234 if (i)
235 strbuf_addch(&msg, ' ');
236 strbuf_addstr(&msg, argv[i]);
237 }
238
239 setenv("GIT_REFLOG_ACTION", msg.buf, 0);
240
241 strbuf_release(&msg);
242}
243
a9de9897
PT
244/**
245 * If pull.ff is unset, returns NULL. If pull.ff is "true", returns "--ff". If
246 * pull.ff is "false", returns "--no-ff". If pull.ff is "only", returns
247 * "--ff-only". Otherwise, if pull.ff is set to an invalid value, die with an
248 * error.
249 */
250static const char *config_get_ff(void)
251{
252 const char *value;
253
254 if (git_config_get_value("pull.ff", &value))
255 return NULL;
256
257 switch (git_config_maybe_bool("pull.ff", value)) {
258 case 0:
259 return "--no-ff";
260 case 1:
261 return "--ff";
262 }
263
264 if (!strcmp(value, "only"))
265 return "--ff-only";
266
267 die(_("Invalid value for pull.ff: %s"), value);
268}
269
81dbd768
PT
270/**
271 * Returns the default configured value for --rebase. It first looks for the
272 * value of "branch.$curr_branch.rebase", where $curr_branch is the current
273 * branch, and if HEAD is detached or the configuration key does not exist,
274 * looks for the value of "pull.rebase". If both configuration keys do not
275 * exist, returns REBASE_FALSE.
276 */
277static enum rebase_type config_get_rebase(void)
278{
279 struct branch *curr_branch = branch_get("HEAD");
280 const char *value;
281
282 if (curr_branch) {
283 char *key = xstrfmt("branch.%s.rebase", curr_branch->name);
284
285 if (!git_config_get_value(key, &value)) {
286 enum rebase_type ret = parse_config_rebase(key, value, 1);
287 free(key);
288 return ret;
289 }
290
291 free(key);
292 }
293
294 if (!git_config_get_value("pull.rebase", &value))
295 return parse_config_rebase("pull.rebase", value, 1);
296
297 return REBASE_FALSE;
298}
299
8944969c
PT
300/**
301 * Returns 1 if there are unstaged changes, 0 otherwise.
302 */
303static int has_unstaged_changes(const char *prefix)
304{
305 struct rev_info rev_info;
306 int result;
307
308 init_revisions(&rev_info, prefix);
309 DIFF_OPT_SET(&rev_info.diffopt, IGNORE_SUBMODULES);
310 DIFF_OPT_SET(&rev_info.diffopt, QUICK);
311 diff_setup_done(&rev_info.diffopt);
312 result = run_diff_files(&rev_info, 0);
313 return diff_result_code(&rev_info.diffopt, result);
314}
315
316/**
317 * Returns 1 if there are uncommitted changes, 0 otherwise.
318 */
319static int has_uncommitted_changes(const char *prefix)
320{
321 struct rev_info rev_info;
322 int result;
323
324 if (is_cache_unborn())
325 return 0;
326
327 init_revisions(&rev_info, prefix);
328 DIFF_OPT_SET(&rev_info.diffopt, IGNORE_SUBMODULES);
329 DIFF_OPT_SET(&rev_info.diffopt, QUICK);
330 add_head_to_pending(&rev_info);
331 diff_setup_done(&rev_info.diffopt);
332 result = run_diff_index(&rev_info, 1);
333 return diff_result_code(&rev_info.diffopt, result);
334}
335
336/**
337 * If the work tree has unstaged or uncommitted changes, dies with the
338 * appropriate message.
339 */
340static void die_on_unclean_work_tree(const char *prefix)
341{
342 struct lock_file *lock_file = xcalloc(1, sizeof(*lock_file));
343 int do_die = 0;
344
345 hold_locked_index(lock_file, 0);
346 refresh_cache(REFRESH_QUIET);
347 update_index_if_able(&the_index, lock_file);
348 rollback_lock_file(lock_file);
349
350 if (has_unstaged_changes(prefix)) {
351 error(_("Cannot pull with rebase: You have unstaged changes."));
352 do_die = 1;
353 }
354
355 if (has_uncommitted_changes(prefix)) {
356 if (do_die)
357 error(_("Additionally, your index contains uncommitted changes."));
358 else
359 error(_("Cannot pull with rebase: Your index contains uncommitted changes."));
360 do_die = 1;
361 }
362
363 if (do_die)
364 exit(1);
365}
366
44c175c7
PT
367/**
368 * Appends merge candidates from FETCH_HEAD that are not marked not-for-merge
369 * into merge_heads.
370 */
371static void get_merge_heads(struct sha1_array *merge_heads)
372{
373 const char *filename = git_path("FETCH_HEAD");
374 FILE *fp;
375 struct strbuf sb = STRBUF_INIT;
376 unsigned char sha1[GIT_SHA1_RAWSZ];
377
378 if (!(fp = fopen(filename, "r")))
379 die_errno(_("could not open '%s' for reading"), filename);
380 while (strbuf_getline(&sb, fp, '\n') != EOF) {
381 if (get_sha1_hex(sb.buf, sha1))
382 continue; /* invalid line: does not start with SHA1 */
383 if (starts_with(sb.buf + GIT_SHA1_HEXSZ, "\tnot-for-merge\t"))
384 continue; /* ref is not-for-merge */
385 sha1_array_append(merge_heads, sha1);
386 }
387 fclose(fp);
388 strbuf_release(&sb);
389}
390
391/**
392 * Used by die_no_merge_candidates() as a for_each_remote() callback to
393 * retrieve the name of the remote if the repository only has one remote.
394 */
395static int get_only_remote(struct remote *remote, void *cb_data)
396{
397 const char **remote_name = cb_data;
398
399 if (*remote_name)
400 return -1;
401
402 *remote_name = remote->name;
403 return 0;
404}
405
406/**
407 * Dies with the appropriate reason for why there are no merge candidates:
408 *
409 * 1. We fetched from a specific remote, and a refspec was given, but it ended
410 * up not fetching anything. This is usually because the user provided a
411 * wildcard refspec which had no matches on the remote end.
412 *
413 * 2. We fetched from a non-default remote, but didn't specify a branch to
414 * merge. We can't use the configured one because it applies to the default
415 * remote, thus the user must specify the branches to merge.
416 *
417 * 3. We fetched from the branch's or repo's default remote, but:
418 *
419 * a. We are not on a branch, so there will never be a configured branch to
420 * merge with.
421 *
422 * b. We are on a branch, but there is no configured branch to merge with.
423 *
424 * 4. We fetched from the branch's or repo's default remote, but the configured
425 * branch to merge didn't get fetched. (Either it doesn't exist, or wasn't
426 * part of the configured fetch refspec.)
427 */
428static void NORETURN die_no_merge_candidates(const char *repo, const char **refspecs)
429{
430 struct branch *curr_branch = branch_get("HEAD");
431 const char *remote = curr_branch ? curr_branch->remote_name : NULL;
432
433 if (*refspecs) {
434 fprintf_ln(stderr, _("There are no candidates for merging among the refs that you just fetched."));
435 fprintf_ln(stderr, _("Generally this means that you provided a wildcard refspec which had no\n"
436 "matches on the remote end."));
437 } else if (repo && curr_branch && (!remote || strcmp(repo, remote))) {
438 fprintf_ln(stderr, _("You asked to pull from the remote '%s', but did not specify\n"
439 "a branch. Because this is not the default configured remote\n"
440 "for your current branch, you must specify a branch on the command line."),
441 repo);
442 } else if (!curr_branch) {
443 fprintf_ln(stderr, _("You are not currently on a branch."));
444 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
445 fprintf_ln(stderr, _("See git-pull(1) for details."));
446 fprintf(stderr, "\n");
447 fprintf_ln(stderr, " git pull <remote> <branch>");
448 fprintf(stderr, "\n");
449 } else if (!curr_branch->merge_nr) {
450 const char *remote_name = NULL;
451
452 if (for_each_remote(get_only_remote, &remote_name) || !remote_name)
453 remote_name = "<remote>";
454
455 fprintf_ln(stderr, _("There is no tracking information for the current branch."));
456 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
457 fprintf_ln(stderr, _("See git-pull(1) for details."));
458 fprintf(stderr, "\n");
459 fprintf_ln(stderr, " git pull <remote> <branch>");
460 fprintf(stderr, "\n");
461 fprintf_ln(stderr, _("If you wish to set tracking information for this branch you can do so with:\n"
462 "\n"
463 " git branch --set-upstream-to=%s/<branch> %s\n"),
464 remote_name, curr_branch->name);
465 } else
466 fprintf_ln(stderr, _("Your configuration specifies to merge with the ref '%s'\n"
467 "from the remote, but no such ref was fetched."),
468 *curr_branch->merge_name);
469 exit(1);
470}
471
f2c5baa1
PT
472/**
473 * Parses argv into [<repo> [<refspecs>...]], returning their values in `repo`
474 * as a string and `refspecs` as a null-terminated array of strings. If `repo`
475 * is not provided in argv, it is set to NULL.
476 */
477static void parse_repo_refspecs(int argc, const char **argv, const char **repo,
478 const char ***refspecs)
479{
480 if (argc > 0) {
481 *repo = *argv++;
482 argc--;
483 } else
484 *repo = NULL;
485 *refspecs = argv;
486}
487
488/**
489 * Runs git-fetch, returning its exit status. `repo` and `refspecs` are the
490 * repository and refspecs to fetch, or NULL if they are not provided.
491 */
492static int run_fetch(const char *repo, const char **refspecs)
493{
494 struct argv_array args = ARGV_ARRAY_INIT;
495 int ret;
496
497 argv_array_pushl(&args, "fetch", "--update-head-ok", NULL);
2a747902
PT
498
499 /* Shared options */
500 argv_push_verbosity(&args);
501 if (opt_progress)
502 argv_array_push(&args, opt_progress);
503
a32975f5
PT
504 /* Options passed to git-fetch */
505 if (opt_all)
506 argv_array_push(&args, opt_all);
507 if (opt_append)
508 argv_array_push(&args, opt_append);
509 if (opt_upload_pack)
510 argv_array_push(&args, opt_upload_pack);
511 argv_push_force(&args);
512 if (opt_tags)
513 argv_array_push(&args, opt_tags);
514 if (opt_prune)
515 argv_array_push(&args, opt_prune);
516 if (opt_recurse_submodules)
517 argv_array_push(&args, opt_recurse_submodules);
518 if (opt_dry_run)
519 argv_array_push(&args, "--dry-run");
520 if (opt_keep)
521 argv_array_push(&args, opt_keep);
522 if (opt_depth)
523 argv_array_push(&args, opt_depth);
524 if (opt_unshallow)
525 argv_array_push(&args, opt_unshallow);
526 if (opt_update_shallow)
527 argv_array_push(&args, opt_update_shallow);
528 if (opt_refmap)
529 argv_array_push(&args, opt_refmap);
530
f2c5baa1
PT
531 if (repo) {
532 argv_array_push(&args, repo);
533 argv_array_pushv(&args, refspecs);
534 } else if (*refspecs)
535 die("BUG: refspecs without repo?");
536 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
537 argv_array_clear(&args);
538 return ret;
539}
540
49ec402d
PT
541/**
542 * "Pulls into void" by branching off merge_head.
543 */
544static int pull_into_void(const unsigned char *merge_head,
545 const unsigned char *curr_head)
546{
547 /*
548 * Two-way merge: we treat the index as based on an empty tree,
549 * and try to fast-forward to HEAD. This ensures we will not lose
550 * index/worktree changes that the user already made on the unborn
551 * branch.
552 */
553 if (checkout_fast_forward(EMPTY_TREE_SHA1_BIN, merge_head, 0))
554 return 1;
555
556 if (update_ref("initial pull", "HEAD", merge_head, curr_head, 0, UPDATE_REFS_DIE_ON_ERR))
557 return 1;
558
559 return 0;
560}
561
f2c5baa1
PT
562/**
563 * Runs git-merge, returning its exit status.
564 */
565static int run_merge(void)
566{
567 int ret;
568 struct argv_array args = ARGV_ARRAY_INIT;
569
570 argv_array_pushl(&args, "merge", NULL);
2a747902
PT
571
572 /* Shared options */
573 argv_push_verbosity(&args);
574 if (opt_progress)
575 argv_array_push(&args, opt_progress);
576
11b6d178
PT
577 /* Options passed to git-merge */
578 if (opt_diffstat)
579 argv_array_push(&args, opt_diffstat);
580 if (opt_log)
581 argv_array_push(&args, opt_log);
582 if (opt_squash)
583 argv_array_push(&args, opt_squash);
584 if (opt_commit)
585 argv_array_push(&args, opt_commit);
586 if (opt_edit)
587 argv_array_push(&args, opt_edit);
588 if (opt_ff)
589 argv_array_push(&args, opt_ff);
590 if (opt_verify_signatures)
591 argv_array_push(&args, opt_verify_signatures);
592 argv_array_pushv(&args, opt_strategies.argv);
593 argv_array_pushv(&args, opt_strategy_opts.argv);
594 if (opt_gpg_sign)
595 argv_array_push(&args, opt_gpg_sign);
596
f2c5baa1
PT
597 argv_array_push(&args, "FETCH_HEAD");
598 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
599 argv_array_clear(&args);
600 return ret;
601}
602
1678b81e
PT
603/**
604 * Returns remote's upstream branch for the current branch. If remote is NULL,
605 * the current branch's configured default remote is used. Returns NULL if
606 * `remote` does not name a valid remote, HEAD does not point to a branch,
607 * remote is not the branch's configured remote or the branch does not have any
608 * configured upstream branch.
609 */
610static const char *get_upstream_branch(const char *remote)
611{
612 struct remote *rm;
613 struct branch *curr_branch;
614 const char *curr_branch_remote;
615
616 rm = remote_get(remote);
617 if (!rm)
618 return NULL;
619
620 curr_branch = branch_get("HEAD");
621 if (!curr_branch)
622 return NULL;
623
624 curr_branch_remote = remote_for_branch(curr_branch, NULL);
625 assert(curr_branch_remote);
626
627 if (strcmp(curr_branch_remote, rm->name))
628 return NULL;
629
630 return branch_get_upstream(curr_branch, NULL);
631}
632
633/**
634 * Derives the remote tracking branch from the remote and refspec.
635 *
636 * FIXME: The current implementation assumes the default mapping of
637 * refs/heads/<branch_name> to refs/remotes/<remote_name>/<branch_name>.
638 */
639static const char *get_tracking_branch(const char *remote, const char *refspec)
640{
641 struct refspec *spec;
642 const char *spec_src;
643 const char *merge_branch;
644
645 spec = parse_fetch_refspec(1, &refspec);
646 spec_src = spec->src;
647 if (!*spec_src || !strcmp(spec_src, "HEAD"))
648 spec_src = "HEAD";
649 else if (skip_prefix(spec_src, "heads/", &spec_src))
650 ;
651 else if (skip_prefix(spec_src, "refs/heads/", &spec_src))
652 ;
653 else if (starts_with(spec_src, "refs/") ||
654 starts_with(spec_src, "tags/") ||
655 starts_with(spec_src, "remotes/"))
656 spec_src = "";
657
658 if (*spec_src) {
659 if (!strcmp(remote, "."))
660 merge_branch = mkpath("refs/heads/%s", spec_src);
661 else
662 merge_branch = mkpath("refs/remotes/%s/%s", remote, spec_src);
663 } else
664 merge_branch = NULL;
665
666 free_refspec(1, spec);
667 return merge_branch;
668}
669
670/**
671 * Given the repo and refspecs, sets fork_point to the point at which the
672 * current branch forked from its remote tracking branch. Returns 0 on success,
673 * -1 on failure.
674 */
675static int get_rebase_fork_point(unsigned char *fork_point, const char *repo,
676 const char *refspec)
677{
678 int ret;
679 struct branch *curr_branch;
680 const char *remote_branch;
681 struct child_process cp = CHILD_PROCESS_INIT;
682 struct strbuf sb = STRBUF_INIT;
683
684 curr_branch = branch_get("HEAD");
685 if (!curr_branch)
686 return -1;
687
688 if (refspec)
689 remote_branch = get_tracking_branch(repo, refspec);
690 else
691 remote_branch = get_upstream_branch(repo);
692
693 if (!remote_branch)
694 return -1;
695
696 argv_array_pushl(&cp.args, "merge-base", "--fork-point",
697 remote_branch, curr_branch->name, NULL);
698 cp.no_stdin = 1;
699 cp.no_stderr = 1;
700 cp.git_cmd = 1;
701
702 ret = capture_command(&cp, &sb, GIT_SHA1_HEXSZ);
703 if (ret)
704 goto cleanup;
705
706 ret = get_sha1_hex(sb.buf, fork_point);
707 if (ret)
708 goto cleanup;
709
710cleanup:
711 strbuf_release(&sb);
712 return ret ? -1 : 0;
713}
714
715/**
716 * Sets merge_base to the octopus merge base of curr_head, merge_head and
717 * fork_point. Returns 0 if a merge base is found, 1 otherwise.
718 */
719static int get_octopus_merge_base(unsigned char *merge_base,
720 const unsigned char *curr_head,
721 const unsigned char *merge_head,
722 const unsigned char *fork_point)
723{
724 struct commit_list *revs = NULL, *result;
725
726 commit_list_insert(lookup_commit_reference(curr_head), &revs);
727 commit_list_insert(lookup_commit_reference(merge_head), &revs);
728 if (!is_null_sha1(fork_point))
729 commit_list_insert(lookup_commit_reference(fork_point), &revs);
730
731 result = reduce_heads(get_octopus_merge_bases(revs));
732 free_commit_list(revs);
733 if (!result)
734 return 1;
735
736 hashcpy(merge_base, result->item->object.sha1);
737 return 0;
738}
739
740/**
741 * Given the current HEAD SHA1, the merge head returned from git-fetch and the
742 * fork point calculated by get_rebase_fork_point(), runs git-rebase with the
743 * appropriate arguments and returns its exit status.
744 */
745static int run_rebase(const unsigned char *curr_head,
746 const unsigned char *merge_head,
747 const unsigned char *fork_point)
748{
749 int ret;
750 unsigned char oct_merge_base[GIT_SHA1_RAWSZ];
751 struct argv_array args = ARGV_ARRAY_INIT;
752
753 if (!get_octopus_merge_base(oct_merge_base, curr_head, merge_head, fork_point))
754 if (!is_null_sha1(fork_point) && !hashcmp(oct_merge_base, fork_point))
755 fork_point = NULL;
756
757 argv_array_push(&args, "rebase");
758
759 /* Shared options */
760 argv_push_verbosity(&args);
761
762 /* Options passed to git-rebase */
763 if (opt_rebase == REBASE_PRESERVE)
764 argv_array_push(&args, "--preserve-merges");
765 if (opt_diffstat)
766 argv_array_push(&args, opt_diffstat);
767 argv_array_pushv(&args, opt_strategies.argv);
768 argv_array_pushv(&args, opt_strategy_opts.argv);
769 if (opt_gpg_sign)
770 argv_array_push(&args, opt_gpg_sign);
771
772 argv_array_push(&args, "--onto");
773 argv_array_push(&args, sha1_to_hex(merge_head));
774
775 if (fork_point && !is_null_sha1(fork_point))
776 argv_array_push(&args, sha1_to_hex(fork_point));
777 else
778 argv_array_push(&args, sha1_to_hex(merge_head));
779
780 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
781 argv_array_clear(&args);
782 return ret;
783}
784
1e1ea69f
PT
785int cmd_pull(int argc, const char **argv, const char *prefix)
786{
f2c5baa1 787 const char *repo, **refspecs;
44c175c7 788 struct sha1_array merge_heads = SHA1_ARRAY_INIT;
fe911b8c 789 unsigned char orig_head[GIT_SHA1_RAWSZ], curr_head[GIT_SHA1_RAWSZ];
1678b81e 790 unsigned char rebase_fork_point[GIT_SHA1_RAWSZ];
f2c5baa1 791
1e1ea69f
PT
792 if (!getenv("_GIT_USE_BUILTIN_PULL")) {
793 const char *path = mkpath("%s/git-pull", git_exec_path());
794
795 if (sane_execvp(path, (char **)argv) < 0)
796 die_errno("could not exec %s", path);
797 }
798
41fca098
PT
799 if (!getenv("GIT_REFLOG_ACTION"))
800 set_reflog_message(argc, argv);
801
1e1ea69f
PT
802 argc = parse_options(argc, argv, prefix, pull_options, pull_usage, 0);
803
f2c5baa1
PT
804 parse_repo_refspecs(argc, argv, &repo, &refspecs);
805
a9de9897
PT
806 if (!opt_ff)
807 opt_ff = xstrdup_or_null(config_get_ff());
808
81dbd768
PT
809 if (opt_rebase < 0)
810 opt_rebase = config_get_rebase();
811
4a4cf9e8
PT
812 git_config(git_default_config, NULL);
813
814 if (read_cache_unmerged())
815 die_resolve_conflict("Pull");
816
817 if (file_exists(git_path("MERGE_HEAD")))
818 die_conclude_merge();
819
fe911b8c
PT
820 if (get_sha1("HEAD", orig_head))
821 hashclr(orig_head);
822
8944969c
PT
823 if (opt_rebase) {
824 if (is_null_sha1(orig_head) && !is_cache_unborn())
825 die(_("Updating an unborn branch with changes added to the index."));
826
827 die_on_unclean_work_tree(prefix);
828
1678b81e
PT
829 if (get_rebase_fork_point(rebase_fork_point, repo, *refspecs))
830 hashclr(rebase_fork_point);
8944969c 831 }
1678b81e 832
f2c5baa1
PT
833 if (run_fetch(repo, refspecs))
834 return 1;
835
a32975f5
PT
836 if (opt_dry_run)
837 return 0;
838
fe911b8c
PT
839 if (get_sha1("HEAD", curr_head))
840 hashclr(curr_head);
841
842 if (!is_null_sha1(orig_head) && !is_null_sha1(curr_head) &&
843 hashcmp(orig_head, curr_head)) {
844 /*
845 * The fetch involved updating the current branch.
846 *
847 * The working tree and the index file are still based on
848 * orig_head commit, but we are merging into curr_head.
849 * Update the working tree to match curr_head.
850 */
851
852 warning(_("fetch updated the current branch head.\n"
853 "fast-forwarding your working tree from\n"
854 "commit %s."), sha1_to_hex(orig_head));
855
856 if (checkout_fast_forward(orig_head, curr_head, 0))
857 die(_("Cannot fast-forward your working tree.\n"
858 "After making sure that you saved anything precious from\n"
859 "$ git diff %s\n"
860 "output, run\n"
861 "$ git reset --hard\n"
862 "to recover."), sha1_to_hex(orig_head));
863 }
864
44c175c7
PT
865 get_merge_heads(&merge_heads);
866
867 if (!merge_heads.nr)
868 die_no_merge_candidates(repo, refspecs);
869
49ec402d
PT
870 if (is_null_sha1(orig_head)) {
871 if (merge_heads.nr > 1)
872 die(_("Cannot merge multiple branches into empty head."));
873 return pull_into_void(*merge_heads.sha1, curr_head);
1678b81e
PT
874 } else if (opt_rebase) {
875 if (merge_heads.nr > 1)
876 die(_("Cannot rebase onto multiple branches."));
877 return run_rebase(curr_head, *merge_heads.sha1, rebase_fork_point);
49ec402d
PT
878 } else
879 return run_merge();
1e1ea69f 880}