pull: allow interactive rebase with --rebase=interactive
[git/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 #include "cache.h"
9 #include "builtin.h"
10 #include "parse-options.h"
11 #include "exec_cmd.h"
12 #include "run-command.h"
13 #include "sha1-array.h"
14 #include "remote.h"
15 #include "dir.h"
16 #include "refs.h"
17 #include "revision.h"
18 #include "tempfile.h"
19 #include "lockfile.h"
20
21 enum rebase_type {
22 REBASE_INVALID = -1,
23 REBASE_FALSE = 0,
24 REBASE_TRUE,
25 REBASE_PRESERVE,
26 REBASE_INTERACTIVE
27 };
28
29 /**
30 * Parses the value of --rebase. If value is a false value, returns
31 * REBASE_FALSE. If value is a true value, returns REBASE_TRUE. If value is
32 * "preserve", returns REBASE_PRESERVE. If value is a invalid value, dies with
33 * a fatal error if fatal is true, otherwise returns REBASE_INVALID.
34 */
35 static enum rebase_type parse_config_rebase(const char *key, const char *value,
36 int fatal)
37 {
38 int v = git_config_maybe_bool("pull.rebase", value);
39
40 if (!v)
41 return REBASE_FALSE;
42 else if (v > 0)
43 return REBASE_TRUE;
44 else if (!strcmp(value, "preserve"))
45 return REBASE_PRESERVE;
46 else if (!strcmp(value, "interactive"))
47 return REBASE_INTERACTIVE;
48
49 if (fatal)
50 die(_("Invalid value for %s: %s"), key, value);
51 else
52 error(_("Invalid value for %s: %s"), key, value);
53
54 return REBASE_INVALID;
55 }
56
57 /**
58 * Callback for --rebase, which parses arg with parse_config_rebase().
59 */
60 static int parse_opt_rebase(const struct option *opt, const char *arg, int unset)
61 {
62 enum rebase_type *value = opt->value;
63
64 if (arg)
65 *value = parse_config_rebase("--rebase", arg, 0);
66 else
67 *value = unset ? REBASE_FALSE : REBASE_TRUE;
68 return *value == REBASE_INVALID ? -1 : 0;
69 }
70
71 static const char * const pull_usage[] = {
72 N_("git pull [<options>] [<repository> [<refspec>...]]"),
73 NULL
74 };
75
76 /* Shared options */
77 static int opt_verbosity;
78 static char *opt_progress;
79
80 /* Options passed to git-merge or git-rebase */
81 static enum rebase_type opt_rebase = -1;
82 static char *opt_diffstat;
83 static char *opt_log;
84 static char *opt_squash;
85 static char *opt_commit;
86 static char *opt_edit;
87 static char *opt_ff;
88 static char *opt_verify_signatures;
89 static struct argv_array opt_strategies = ARGV_ARRAY_INIT;
90 static struct argv_array opt_strategy_opts = ARGV_ARRAY_INIT;
91 static char *opt_gpg_sign;
92
93 /* Options passed to git-fetch */
94 static char *opt_all;
95 static char *opt_append;
96 static char *opt_upload_pack;
97 static int opt_force;
98 static char *opt_tags;
99 static char *opt_prune;
100 static char *opt_recurse_submodules;
101 static int opt_dry_run;
102 static char *opt_keep;
103 static char *opt_depth;
104 static char *opt_unshallow;
105 static char *opt_update_shallow;
106 static char *opt_refmap;
107
108 static struct option pull_options[] = {
109 /* Shared options */
110 OPT__VERBOSITY(&opt_verbosity),
111 OPT_PASSTHRU(0, "progress", &opt_progress, NULL,
112 N_("force progress reporting"),
113 PARSE_OPT_NOARG),
114
115 /* Options passed to git-merge or git-rebase */
116 OPT_GROUP(N_("Options related to merging")),
117 { OPTION_CALLBACK, 'r', "rebase", &opt_rebase,
118 "false|true|preserve|interactive",
119 N_("incorporate changes by rebasing rather than merging"),
120 PARSE_OPT_OPTARG, parse_opt_rebase },
121 OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL,
122 N_("do not show a diffstat at the end of the merge"),
123 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
124 OPT_PASSTHRU(0, "stat", &opt_diffstat, NULL,
125 N_("show a diffstat at the end of the merge"),
126 PARSE_OPT_NOARG),
127 OPT_PASSTHRU(0, "summary", &opt_diffstat, NULL,
128 N_("(synonym to --stat)"),
129 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN),
130 OPT_PASSTHRU(0, "log", &opt_log, N_("n"),
131 N_("add (at most <n>) entries from shortlog to merge commit message"),
132 PARSE_OPT_OPTARG),
133 OPT_PASSTHRU(0, "squash", &opt_squash, NULL,
134 N_("create a single commit instead of doing a merge"),
135 PARSE_OPT_NOARG),
136 OPT_PASSTHRU(0, "commit", &opt_commit, NULL,
137 N_("perform a commit if the merge succeeds (default)"),
138 PARSE_OPT_NOARG),
139 OPT_PASSTHRU(0, "edit", &opt_edit, NULL,
140 N_("edit message before committing"),
141 PARSE_OPT_NOARG),
142 OPT_PASSTHRU(0, "ff", &opt_ff, NULL,
143 N_("allow fast-forward"),
144 PARSE_OPT_NOARG),
145 OPT_PASSTHRU(0, "ff-only", &opt_ff, NULL,
146 N_("abort if fast-forward is not possible"),
147 PARSE_OPT_NOARG | PARSE_OPT_NONEG),
148 OPT_PASSTHRU(0, "verify-signatures", &opt_verify_signatures, NULL,
149 N_("verify that the named commit has a valid GPG signature"),
150 PARSE_OPT_NOARG),
151 OPT_PASSTHRU_ARGV('s', "strategy", &opt_strategies, N_("strategy"),
152 N_("merge strategy to use"),
153 0),
154 OPT_PASSTHRU_ARGV('X', "strategy-option", &opt_strategy_opts,
155 N_("option=value"),
156 N_("option for selected merge strategy"),
157 0),
158 OPT_PASSTHRU('S', "gpg-sign", &opt_gpg_sign, N_("key-id"),
159 N_("GPG sign commit"),
160 PARSE_OPT_OPTARG),
161
162 /* Options passed to git-fetch */
163 OPT_GROUP(N_("Options related to fetching")),
164 OPT_PASSTHRU(0, "all", &opt_all, NULL,
165 N_("fetch from all remotes"),
166 PARSE_OPT_NOARG),
167 OPT_PASSTHRU('a', "append", &opt_append, NULL,
168 N_("append to .git/FETCH_HEAD instead of overwriting"),
169 PARSE_OPT_NOARG),
170 OPT_PASSTHRU(0, "upload-pack", &opt_upload_pack, N_("path"),
171 N_("path to upload pack on remote end"),
172 0),
173 OPT__FORCE(&opt_force, N_("force overwrite of local branch")),
174 OPT_PASSTHRU('t', "tags", &opt_tags, NULL,
175 N_("fetch all tags and associated objects"),
176 PARSE_OPT_NOARG),
177 OPT_PASSTHRU('p', "prune", &opt_prune, NULL,
178 N_("prune remote-tracking branches no longer on remote"),
179 PARSE_OPT_NOARG),
180 OPT_PASSTHRU(0, "recurse-submodules", &opt_recurse_submodules,
181 N_("on-demand"),
182 N_("control recursive fetching of submodules"),
183 PARSE_OPT_OPTARG),
184 OPT_BOOL(0, "dry-run", &opt_dry_run,
185 N_("dry run")),
186 OPT_PASSTHRU('k', "keep", &opt_keep, NULL,
187 N_("keep downloaded pack"),
188 PARSE_OPT_NOARG),
189 OPT_PASSTHRU(0, "depth", &opt_depth, N_("depth"),
190 N_("deepen history of shallow clone"),
191 0),
192 OPT_PASSTHRU(0, "unshallow", &opt_unshallow, NULL,
193 N_("convert to a complete repository"),
194 PARSE_OPT_NONEG | PARSE_OPT_NOARG),
195 OPT_PASSTHRU(0, "update-shallow", &opt_update_shallow, NULL,
196 N_("accept refs that update .git/shallow"),
197 PARSE_OPT_NOARG),
198 OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"),
199 N_("specify fetch refmap"),
200 PARSE_OPT_NONEG),
201
202 OPT_END()
203 };
204
205 /**
206 * Pushes "-q" or "-v" switches into arr to match the opt_verbosity level.
207 */
208 static void argv_push_verbosity(struct argv_array *arr)
209 {
210 int verbosity;
211
212 for (verbosity = opt_verbosity; verbosity > 0; verbosity--)
213 argv_array_push(arr, "-v");
214
215 for (verbosity = opt_verbosity; verbosity < 0; verbosity++)
216 argv_array_push(arr, "-q");
217 }
218
219 /**
220 * Pushes "-f" switches into arr to match the opt_force level.
221 */
222 static void argv_push_force(struct argv_array *arr)
223 {
224 int force = opt_force;
225 while (force-- > 0)
226 argv_array_push(arr, "-f");
227 }
228
229 /**
230 * Sets the GIT_REFLOG_ACTION environment variable to the concatenation of argv
231 */
232 static void set_reflog_message(int argc, const char **argv)
233 {
234 int i;
235 struct strbuf msg = STRBUF_INIT;
236
237 for (i = 0; i < argc; i++) {
238 if (i)
239 strbuf_addch(&msg, ' ');
240 strbuf_addstr(&msg, argv[i]);
241 }
242
243 setenv("GIT_REFLOG_ACTION", msg.buf, 0);
244
245 strbuf_release(&msg);
246 }
247
248 /**
249 * If pull.ff is unset, returns NULL. If pull.ff is "true", returns "--ff". If
250 * pull.ff is "false", returns "--no-ff". If pull.ff is "only", returns
251 * "--ff-only". Otherwise, if pull.ff is set to an invalid value, die with an
252 * error.
253 */
254 static const char *config_get_ff(void)
255 {
256 const char *value;
257
258 if (git_config_get_value("pull.ff", &value))
259 return NULL;
260
261 switch (git_config_maybe_bool("pull.ff", value)) {
262 case 0:
263 return "--no-ff";
264 case 1:
265 return "--ff";
266 }
267
268 if (!strcmp(value, "only"))
269 return "--ff-only";
270
271 die(_("Invalid value for pull.ff: %s"), value);
272 }
273
274 /**
275 * Returns the default configured value for --rebase. It first looks for the
276 * value of "branch.$curr_branch.rebase", where $curr_branch is the current
277 * branch, and if HEAD is detached or the configuration key does not exist,
278 * looks for the value of "pull.rebase". If both configuration keys do not
279 * exist, returns REBASE_FALSE.
280 */
281 static enum rebase_type config_get_rebase(void)
282 {
283 struct branch *curr_branch = branch_get("HEAD");
284 const char *value;
285
286 if (curr_branch) {
287 char *key = xstrfmt("branch.%s.rebase", curr_branch->name);
288
289 if (!git_config_get_value(key, &value)) {
290 enum rebase_type ret = parse_config_rebase(key, value, 1);
291 free(key);
292 return ret;
293 }
294
295 free(key);
296 }
297
298 if (!git_config_get_value("pull.rebase", &value))
299 return parse_config_rebase("pull.rebase", value, 1);
300
301 return REBASE_FALSE;
302 }
303
304 /**
305 * Returns 1 if there are unstaged changes, 0 otherwise.
306 */
307 static int has_unstaged_changes(const char *prefix)
308 {
309 struct rev_info rev_info;
310 int result;
311
312 init_revisions(&rev_info, prefix);
313 DIFF_OPT_SET(&rev_info.diffopt, IGNORE_SUBMODULES);
314 DIFF_OPT_SET(&rev_info.diffopt, QUICK);
315 diff_setup_done(&rev_info.diffopt);
316 result = run_diff_files(&rev_info, 0);
317 return diff_result_code(&rev_info.diffopt, result);
318 }
319
320 /**
321 * Returns 1 if there are uncommitted changes, 0 otherwise.
322 */
323 static int has_uncommitted_changes(const char *prefix)
324 {
325 struct rev_info rev_info;
326 int result;
327
328 if (is_cache_unborn())
329 return 0;
330
331 init_revisions(&rev_info, prefix);
332 DIFF_OPT_SET(&rev_info.diffopt, IGNORE_SUBMODULES);
333 DIFF_OPT_SET(&rev_info.diffopt, QUICK);
334 add_head_to_pending(&rev_info);
335 diff_setup_done(&rev_info.diffopt);
336 result = run_diff_index(&rev_info, 1);
337 return diff_result_code(&rev_info.diffopt, result);
338 }
339
340 /**
341 * If the work tree has unstaged or uncommitted changes, dies with the
342 * appropriate message.
343 */
344 static void die_on_unclean_work_tree(const char *prefix)
345 {
346 struct lock_file *lock_file = xcalloc(1, sizeof(*lock_file));
347 int do_die = 0;
348
349 hold_locked_index(lock_file, 0);
350 refresh_cache(REFRESH_QUIET);
351 update_index_if_able(&the_index, lock_file);
352 rollback_lock_file(lock_file);
353
354 if (has_unstaged_changes(prefix)) {
355 error(_("Cannot pull with rebase: You have unstaged changes."));
356 do_die = 1;
357 }
358
359 if (has_uncommitted_changes(prefix)) {
360 if (do_die)
361 error(_("Additionally, your index contains uncommitted changes."));
362 else
363 error(_("Cannot pull with rebase: Your index contains uncommitted changes."));
364 do_die = 1;
365 }
366
367 if (do_die)
368 exit(1);
369 }
370
371 /**
372 * Appends merge candidates from FETCH_HEAD that are not marked not-for-merge
373 * into merge_heads.
374 */
375 static void get_merge_heads(struct sha1_array *merge_heads)
376 {
377 const char *filename = git_path("FETCH_HEAD");
378 FILE *fp;
379 struct strbuf sb = STRBUF_INIT;
380 unsigned char sha1[GIT_SHA1_RAWSZ];
381
382 if (!(fp = fopen(filename, "r")))
383 die_errno(_("could not open '%s' for reading"), filename);
384 while (strbuf_getline(&sb, fp, '\n') != EOF) {
385 if (get_sha1_hex(sb.buf, sha1))
386 continue; /* invalid line: does not start with SHA1 */
387 if (starts_with(sb.buf + GIT_SHA1_HEXSZ, "\tnot-for-merge\t"))
388 continue; /* ref is not-for-merge */
389 sha1_array_append(merge_heads, sha1);
390 }
391 fclose(fp);
392 strbuf_release(&sb);
393 }
394
395 /**
396 * Used by die_no_merge_candidates() as a for_each_remote() callback to
397 * retrieve the name of the remote if the repository only has one remote.
398 */
399 static int get_only_remote(struct remote *remote, void *cb_data)
400 {
401 const char **remote_name = cb_data;
402
403 if (*remote_name)
404 return -1;
405
406 *remote_name = remote->name;
407 return 0;
408 }
409
410 /**
411 * Dies with the appropriate reason for why there are no merge candidates:
412 *
413 * 1. We fetched from a specific remote, and a refspec was given, but it ended
414 * up not fetching anything. This is usually because the user provided a
415 * wildcard refspec which had no matches on the remote end.
416 *
417 * 2. We fetched from a non-default remote, but didn't specify a branch to
418 * merge. We can't use the configured one because it applies to the default
419 * remote, thus the user must specify the branches to merge.
420 *
421 * 3. We fetched from the branch's or repo's default remote, but:
422 *
423 * a. We are not on a branch, so there will never be a configured branch to
424 * merge with.
425 *
426 * b. We are on a branch, but there is no configured branch to merge with.
427 *
428 * 4. We fetched from the branch's or repo's default remote, but the configured
429 * branch to merge didn't get fetched. (Either it doesn't exist, or wasn't
430 * part of the configured fetch refspec.)
431 */
432 static void NORETURN die_no_merge_candidates(const char *repo, const char **refspecs)
433 {
434 struct branch *curr_branch = branch_get("HEAD");
435 const char *remote = curr_branch ? curr_branch->remote_name : NULL;
436
437 if (*refspecs) {
438 if (opt_rebase)
439 fprintf_ln(stderr, _("There is no candidate for rebasing against among the refs that you just fetched."));
440 else
441 fprintf_ln(stderr, _("There are no candidates for merging among the refs that you just fetched."));
442 fprintf_ln(stderr, _("Generally this means that you provided a wildcard refspec which had no\n"
443 "matches on the remote end."));
444 } else if (repo && curr_branch && (!remote || strcmp(repo, remote))) {
445 fprintf_ln(stderr, _("You asked to pull from the remote '%s', but did not specify\n"
446 "a branch. Because this is not the default configured remote\n"
447 "for your current branch, you must specify a branch on the command line."),
448 repo);
449 } else if (!curr_branch) {
450 fprintf_ln(stderr, _("You are not currently on a branch."));
451 if (opt_rebase)
452 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
453 else
454 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
455 fprintf_ln(stderr, _("See git-pull(1) for details."));
456 fprintf(stderr, "\n");
457 fprintf_ln(stderr, " git pull <remote> <branch>");
458 fprintf(stderr, "\n");
459 } else if (!curr_branch->merge_nr) {
460 const char *remote_name = NULL;
461
462 if (for_each_remote(get_only_remote, &remote_name) || !remote_name)
463 remote_name = "<remote>";
464
465 fprintf_ln(stderr, _("There is no tracking information for the current branch."));
466 if (opt_rebase)
467 fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
468 else
469 fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
470 fprintf_ln(stderr, _("See git-pull(1) for details."));
471 fprintf(stderr, "\n");
472 fprintf_ln(stderr, " git pull <remote> <branch>");
473 fprintf(stderr, "\n");
474 fprintf_ln(stderr, _("If you wish to set tracking information for this branch you can do so with:\n"
475 "\n"
476 " git branch --set-upstream-to=%s/<branch> %s\n"),
477 remote_name, curr_branch->name);
478 } else
479 fprintf_ln(stderr, _("Your configuration specifies to merge with the ref '%s'\n"
480 "from the remote, but no such ref was fetched."),
481 *curr_branch->merge_name);
482 exit(1);
483 }
484
485 /**
486 * Parses argv into [<repo> [<refspecs>...]], returning their values in `repo`
487 * as a string and `refspecs` as a null-terminated array of strings. If `repo`
488 * is not provided in argv, it is set to NULL.
489 */
490 static void parse_repo_refspecs(int argc, const char **argv, const char **repo,
491 const char ***refspecs)
492 {
493 if (argc > 0) {
494 *repo = *argv++;
495 argc--;
496 } else
497 *repo = NULL;
498 *refspecs = argv;
499 }
500
501 /**
502 * Runs git-fetch, returning its exit status. `repo` and `refspecs` are the
503 * repository and refspecs to fetch, or NULL if they are not provided.
504 */
505 static int run_fetch(const char *repo, const char **refspecs)
506 {
507 struct argv_array args = ARGV_ARRAY_INIT;
508 int ret;
509
510 argv_array_pushl(&args, "fetch", "--update-head-ok", NULL);
511
512 /* Shared options */
513 argv_push_verbosity(&args);
514 if (opt_progress)
515 argv_array_push(&args, opt_progress);
516
517 /* Options passed to git-fetch */
518 if (opt_all)
519 argv_array_push(&args, opt_all);
520 if (opt_append)
521 argv_array_push(&args, opt_append);
522 if (opt_upload_pack)
523 argv_array_push(&args, opt_upload_pack);
524 argv_push_force(&args);
525 if (opt_tags)
526 argv_array_push(&args, opt_tags);
527 if (opt_prune)
528 argv_array_push(&args, opt_prune);
529 if (opt_recurse_submodules)
530 argv_array_push(&args, opt_recurse_submodules);
531 if (opt_dry_run)
532 argv_array_push(&args, "--dry-run");
533 if (opt_keep)
534 argv_array_push(&args, opt_keep);
535 if (opt_depth)
536 argv_array_push(&args, opt_depth);
537 if (opt_unshallow)
538 argv_array_push(&args, opt_unshallow);
539 if (opt_update_shallow)
540 argv_array_push(&args, opt_update_shallow);
541 if (opt_refmap)
542 argv_array_push(&args, opt_refmap);
543
544 if (repo) {
545 argv_array_push(&args, repo);
546 argv_array_pushv(&args, refspecs);
547 } else if (*refspecs)
548 die("BUG: refspecs without repo?");
549 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
550 argv_array_clear(&args);
551 return ret;
552 }
553
554 /**
555 * "Pulls into void" by branching off merge_head.
556 */
557 static int pull_into_void(const unsigned char *merge_head,
558 const unsigned char *curr_head)
559 {
560 /*
561 * Two-way merge: we treat the index as based on an empty tree,
562 * and try to fast-forward to HEAD. This ensures we will not lose
563 * index/worktree changes that the user already made on the unborn
564 * branch.
565 */
566 if (checkout_fast_forward(EMPTY_TREE_SHA1_BIN, merge_head, 0))
567 return 1;
568
569 if (update_ref("initial pull", "HEAD", merge_head, curr_head, 0, UPDATE_REFS_DIE_ON_ERR))
570 return 1;
571
572 return 0;
573 }
574
575 /**
576 * Runs git-merge, returning its exit status.
577 */
578 static int run_merge(void)
579 {
580 int ret;
581 struct argv_array args = ARGV_ARRAY_INIT;
582
583 argv_array_pushl(&args, "merge", NULL);
584
585 /* Shared options */
586 argv_push_verbosity(&args);
587 if (opt_progress)
588 argv_array_push(&args, opt_progress);
589
590 /* Options passed to git-merge */
591 if (opt_diffstat)
592 argv_array_push(&args, opt_diffstat);
593 if (opt_log)
594 argv_array_push(&args, opt_log);
595 if (opt_squash)
596 argv_array_push(&args, opt_squash);
597 if (opt_commit)
598 argv_array_push(&args, opt_commit);
599 if (opt_edit)
600 argv_array_push(&args, opt_edit);
601 if (opt_ff)
602 argv_array_push(&args, opt_ff);
603 if (opt_verify_signatures)
604 argv_array_push(&args, opt_verify_signatures);
605 argv_array_pushv(&args, opt_strategies.argv);
606 argv_array_pushv(&args, opt_strategy_opts.argv);
607 if (opt_gpg_sign)
608 argv_array_push(&args, opt_gpg_sign);
609
610 argv_array_push(&args, "FETCH_HEAD");
611 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
612 argv_array_clear(&args);
613 return ret;
614 }
615
616 /**
617 * Returns remote's upstream branch for the current branch. If remote is NULL,
618 * the current branch's configured default remote is used. Returns NULL if
619 * `remote` does not name a valid remote, HEAD does not point to a branch,
620 * remote is not the branch's configured remote or the branch does not have any
621 * configured upstream branch.
622 */
623 static const char *get_upstream_branch(const char *remote)
624 {
625 struct remote *rm;
626 struct branch *curr_branch;
627 const char *curr_branch_remote;
628
629 rm = remote_get(remote);
630 if (!rm)
631 return NULL;
632
633 curr_branch = branch_get("HEAD");
634 if (!curr_branch)
635 return NULL;
636
637 curr_branch_remote = remote_for_branch(curr_branch, NULL);
638 assert(curr_branch_remote);
639
640 if (strcmp(curr_branch_remote, rm->name))
641 return NULL;
642
643 return branch_get_upstream(curr_branch, NULL);
644 }
645
646 /**
647 * Derives the remote tracking branch from the remote and refspec.
648 *
649 * FIXME: The current implementation assumes the default mapping of
650 * refs/heads/<branch_name> to refs/remotes/<remote_name>/<branch_name>.
651 */
652 static const char *get_tracking_branch(const char *remote, const char *refspec)
653 {
654 struct refspec *spec;
655 const char *spec_src;
656 const char *merge_branch;
657
658 spec = parse_fetch_refspec(1, &refspec);
659 spec_src = spec->src;
660 if (!*spec_src || !strcmp(spec_src, "HEAD"))
661 spec_src = "HEAD";
662 else if (skip_prefix(spec_src, "heads/", &spec_src))
663 ;
664 else if (skip_prefix(spec_src, "refs/heads/", &spec_src))
665 ;
666 else if (starts_with(spec_src, "refs/") ||
667 starts_with(spec_src, "tags/") ||
668 starts_with(spec_src, "remotes/"))
669 spec_src = "";
670
671 if (*spec_src) {
672 if (!strcmp(remote, "."))
673 merge_branch = mkpath("refs/heads/%s", spec_src);
674 else
675 merge_branch = mkpath("refs/remotes/%s/%s", remote, spec_src);
676 } else
677 merge_branch = NULL;
678
679 free_refspec(1, spec);
680 return merge_branch;
681 }
682
683 /**
684 * Given the repo and refspecs, sets fork_point to the point at which the
685 * current branch forked from its remote tracking branch. Returns 0 on success,
686 * -1 on failure.
687 */
688 static int get_rebase_fork_point(unsigned char *fork_point, const char *repo,
689 const char *refspec)
690 {
691 int ret;
692 struct branch *curr_branch;
693 const char *remote_branch;
694 struct child_process cp = CHILD_PROCESS_INIT;
695 struct strbuf sb = STRBUF_INIT;
696
697 curr_branch = branch_get("HEAD");
698 if (!curr_branch)
699 return -1;
700
701 if (refspec)
702 remote_branch = get_tracking_branch(repo, refspec);
703 else
704 remote_branch = get_upstream_branch(repo);
705
706 if (!remote_branch)
707 return -1;
708
709 argv_array_pushl(&cp.args, "merge-base", "--fork-point",
710 remote_branch, curr_branch->name, NULL);
711 cp.no_stdin = 1;
712 cp.no_stderr = 1;
713 cp.git_cmd = 1;
714
715 ret = capture_command(&cp, &sb, GIT_SHA1_HEXSZ);
716 if (ret)
717 goto cleanup;
718
719 ret = get_sha1_hex(sb.buf, fork_point);
720 if (ret)
721 goto cleanup;
722
723 cleanup:
724 strbuf_release(&sb);
725 return ret ? -1 : 0;
726 }
727
728 /**
729 * Sets merge_base to the octopus merge base of curr_head, merge_head and
730 * fork_point. Returns 0 if a merge base is found, 1 otherwise.
731 */
732 static int get_octopus_merge_base(unsigned char *merge_base,
733 const unsigned char *curr_head,
734 const unsigned char *merge_head,
735 const unsigned char *fork_point)
736 {
737 struct commit_list *revs = NULL, *result;
738
739 commit_list_insert(lookup_commit_reference(curr_head), &revs);
740 commit_list_insert(lookup_commit_reference(merge_head), &revs);
741 if (!is_null_sha1(fork_point))
742 commit_list_insert(lookup_commit_reference(fork_point), &revs);
743
744 result = reduce_heads(get_octopus_merge_bases(revs));
745 free_commit_list(revs);
746 if (!result)
747 return 1;
748
749 hashcpy(merge_base, result->item->object.oid.hash);
750 return 0;
751 }
752
753 /**
754 * Given the current HEAD SHA1, the merge head returned from git-fetch and the
755 * fork point calculated by get_rebase_fork_point(), runs git-rebase with the
756 * appropriate arguments and returns its exit status.
757 */
758 static int run_rebase(const unsigned char *curr_head,
759 const unsigned char *merge_head,
760 const unsigned char *fork_point)
761 {
762 int ret;
763 unsigned char oct_merge_base[GIT_SHA1_RAWSZ];
764 struct argv_array args = ARGV_ARRAY_INIT;
765
766 if (!get_octopus_merge_base(oct_merge_base, curr_head, merge_head, fork_point))
767 if (!is_null_sha1(fork_point) && !hashcmp(oct_merge_base, fork_point))
768 fork_point = NULL;
769
770 argv_array_push(&args, "rebase");
771
772 /* Shared options */
773 argv_push_verbosity(&args);
774
775 /* Options passed to git-rebase */
776 if (opt_rebase == REBASE_PRESERVE)
777 argv_array_push(&args, "--preserve-merges");
778 else if (opt_rebase == REBASE_INTERACTIVE)
779 argv_array_push(&args, "--interactive");
780 if (opt_diffstat)
781 argv_array_push(&args, opt_diffstat);
782 argv_array_pushv(&args, opt_strategies.argv);
783 argv_array_pushv(&args, opt_strategy_opts.argv);
784 if (opt_gpg_sign)
785 argv_array_push(&args, opt_gpg_sign);
786
787 argv_array_push(&args, "--onto");
788 argv_array_push(&args, sha1_to_hex(merge_head));
789
790 if (fork_point && !is_null_sha1(fork_point))
791 argv_array_push(&args, sha1_to_hex(fork_point));
792 else
793 argv_array_push(&args, sha1_to_hex(merge_head));
794
795 ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
796 argv_array_clear(&args);
797 return ret;
798 }
799
800 int cmd_pull(int argc, const char **argv, const char *prefix)
801 {
802 const char *repo, **refspecs;
803 struct sha1_array merge_heads = SHA1_ARRAY_INIT;
804 unsigned char orig_head[GIT_SHA1_RAWSZ], curr_head[GIT_SHA1_RAWSZ];
805 unsigned char rebase_fork_point[GIT_SHA1_RAWSZ];
806
807 if (!getenv("GIT_REFLOG_ACTION"))
808 set_reflog_message(argc, argv);
809
810 argc = parse_options(argc, argv, prefix, pull_options, pull_usage, 0);
811
812 parse_repo_refspecs(argc, argv, &repo, &refspecs);
813
814 if (!opt_ff)
815 opt_ff = xstrdup_or_null(config_get_ff());
816
817 if (opt_rebase < 0)
818 opt_rebase = config_get_rebase();
819
820 git_config(git_default_config, NULL);
821
822 if (read_cache_unmerged())
823 die_resolve_conflict("Pull");
824
825 if (file_exists(git_path("MERGE_HEAD")))
826 die_conclude_merge();
827
828 if (get_sha1("HEAD", orig_head))
829 hashclr(orig_head);
830
831 if (opt_rebase) {
832 int autostash = 0;
833
834 if (is_null_sha1(orig_head) && !is_cache_unborn())
835 die(_("Updating an unborn branch with changes added to the index."));
836
837 git_config_get_bool("rebase.autostash", &autostash);
838 if (!autostash)
839 die_on_unclean_work_tree(prefix);
840
841 if (get_rebase_fork_point(rebase_fork_point, repo, *refspecs))
842 hashclr(rebase_fork_point);
843 }
844
845 if (run_fetch(repo, refspecs))
846 return 1;
847
848 if (opt_dry_run)
849 return 0;
850
851 if (get_sha1("HEAD", curr_head))
852 hashclr(curr_head);
853
854 if (!is_null_sha1(orig_head) && !is_null_sha1(curr_head) &&
855 hashcmp(orig_head, curr_head)) {
856 /*
857 * The fetch involved updating the current branch.
858 *
859 * The working tree and the index file are still based on
860 * orig_head commit, but we are merging into curr_head.
861 * Update the working tree to match curr_head.
862 */
863
864 warning(_("fetch updated the current branch head.\n"
865 "fast-forwarding your working tree from\n"
866 "commit %s."), sha1_to_hex(orig_head));
867
868 if (checkout_fast_forward(orig_head, curr_head, 0))
869 die(_("Cannot fast-forward your working tree.\n"
870 "After making sure that you saved anything precious from\n"
871 "$ git diff %s\n"
872 "output, run\n"
873 "$ git reset --hard\n"
874 "to recover."), sha1_to_hex(orig_head));
875 }
876
877 get_merge_heads(&merge_heads);
878
879 if (!merge_heads.nr)
880 die_no_merge_candidates(repo, refspecs);
881
882 if (is_null_sha1(orig_head)) {
883 if (merge_heads.nr > 1)
884 die(_("Cannot merge multiple branches into empty head."));
885 return pull_into_void(*merge_heads.sha1, curr_head);
886 } else if (opt_rebase) {
887 if (merge_heads.nr > 1)
888 die(_("Cannot rebase onto multiple branches."));
889 return run_rebase(curr_head, *merge_heads.sha1, rebase_fork_point);
890 } else
891 return run_merge();
892 }