Merge branch 'jt/http-redact-cookies' into maint
[git.git] / builtin / merge.c
blob30264cfd7c1720aee814699eb3ca057e292b082d
1 /*
2 * Builtin "git merge"
4 * Copyright (c) 2008 Miklos Vajna <vmiklos@frugalware.org>
6 * Based on git-merge.sh by Junio C Hamano.
7 */
9 #include "cache.h"
10 #include "config.h"
11 #include "parse-options.h"
12 #include "builtin.h"
13 #include "lockfile.h"
14 #include "run-command.h"
15 #include "diff.h"
16 #include "refs.h"
17 #include "commit.h"
18 #include "diffcore.h"
19 #include "revision.h"
20 #include "unpack-trees.h"
21 #include "cache-tree.h"
22 #include "dir.h"
23 #include "utf8.h"
24 #include "log-tree.h"
25 #include "color.h"
26 #include "rerere.h"
27 #include "help.h"
28 #include "merge-recursive.h"
29 #include "resolve-undo.h"
30 #include "remote.h"
31 #include "fmt-merge-msg.h"
32 #include "gpg-interface.h"
33 #include "sequencer.h"
34 #include "string-list.h"
35 #include "packfile.h"
37 #define DEFAULT_TWOHEAD (1<<0)
38 #define DEFAULT_OCTOPUS (1<<1)
39 #define NO_FAST_FORWARD (1<<2)
40 #define NO_TRIVIAL (1<<3)
42 struct strategy {
43 const char *name;
44 unsigned attr;
47 static const char * const builtin_merge_usage[] = {
48 N_("git merge [<options>] [<commit>...]"),
49 N_("git merge --abort"),
50 N_("git merge --continue"),
51 NULL
54 static int show_diffstat = 1, shortlog_len = -1, squash;
55 static int option_commit = 1;
56 static int option_edit = -1;
57 static int allow_trivial = 1, have_message, verify_signatures;
58 static int overwrite_ignore = 1;
59 static struct strbuf merge_msg = STRBUF_INIT;
60 static struct strategy **use_strategies;
61 static size_t use_strategies_nr, use_strategies_alloc;
62 static const char **xopts;
63 static size_t xopts_nr, xopts_alloc;
64 static const char *branch;
65 static char *branch_mergeoptions;
66 static int option_renormalize;
67 static int verbosity;
68 static int allow_rerere_auto;
69 static int abort_current_merge;
70 static int continue_current_merge;
71 static int allow_unrelated_histories;
72 static int show_progress = -1;
73 static int default_to_upstream = 1;
74 static int signoff;
75 static const char *sign_commit;
76 static int verify_msg = 1;
78 static struct strategy all_strategy[] = {
79 { "recursive", DEFAULT_TWOHEAD | NO_TRIVIAL },
80 { "octopus", DEFAULT_OCTOPUS },
81 { "resolve", 0 },
82 { "ours", NO_FAST_FORWARD | NO_TRIVIAL },
83 { "subtree", NO_FAST_FORWARD | NO_TRIVIAL },
86 static const char *pull_twohead, *pull_octopus;
88 enum ff_type {
89 FF_NO,
90 FF_ALLOW,
91 FF_ONLY
94 static enum ff_type fast_forward = FF_ALLOW;
96 static int option_parse_message(const struct option *opt,
97 const char *arg, int unset)
99 struct strbuf *buf = opt->value;
101 if (unset)
102 strbuf_setlen(buf, 0);
103 else if (arg) {
104 strbuf_addf(buf, "%s%s", buf->len ? "\n\n" : "", arg);
105 have_message = 1;
106 } else
107 return error(_("switch `m' requires a value"));
108 return 0;
111 static struct strategy *get_strategy(const char *name)
113 int i;
114 struct strategy *ret;
115 static struct cmdnames main_cmds, other_cmds;
116 static int loaded;
118 if (!name)
119 return NULL;
121 for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
122 if (!strcmp(name, all_strategy[i].name))
123 return &all_strategy[i];
125 if (!loaded) {
126 struct cmdnames not_strategies;
127 loaded = 1;
129 memset(&not_strategies, 0, sizeof(struct cmdnames));
130 load_command_list("git-merge-", &main_cmds, &other_cmds);
131 for (i = 0; i < main_cmds.cnt; i++) {
132 int j, found = 0;
133 struct cmdname *ent = main_cmds.names[i];
134 for (j = 0; j < ARRAY_SIZE(all_strategy); j++)
135 if (!strncmp(ent->name, all_strategy[j].name, ent->len)
136 && !all_strategy[j].name[ent->len])
137 found = 1;
138 if (!found)
139 add_cmdname(&not_strategies, ent->name, ent->len);
141 exclude_cmds(&main_cmds, &not_strategies);
143 if (!is_in_cmdlist(&main_cmds, name) && !is_in_cmdlist(&other_cmds, name)) {
144 fprintf(stderr, _("Could not find merge strategy '%s'.\n"), name);
145 fprintf(stderr, _("Available strategies are:"));
146 for (i = 0; i < main_cmds.cnt; i++)
147 fprintf(stderr, " %s", main_cmds.names[i]->name);
148 fprintf(stderr, ".\n");
149 if (other_cmds.cnt) {
150 fprintf(stderr, _("Available custom strategies are:"));
151 for (i = 0; i < other_cmds.cnt; i++)
152 fprintf(stderr, " %s", other_cmds.names[i]->name);
153 fprintf(stderr, ".\n");
155 exit(1);
158 ret = xcalloc(1, sizeof(struct strategy));
159 ret->name = xstrdup(name);
160 ret->attr = NO_TRIVIAL;
161 return ret;
164 static void append_strategy(struct strategy *s)
166 ALLOC_GROW(use_strategies, use_strategies_nr + 1, use_strategies_alloc);
167 use_strategies[use_strategies_nr++] = s;
170 static int option_parse_strategy(const struct option *opt,
171 const char *name, int unset)
173 if (unset)
174 return 0;
176 append_strategy(get_strategy(name));
177 return 0;
180 static int option_parse_x(const struct option *opt,
181 const char *arg, int unset)
183 if (unset)
184 return 0;
186 ALLOC_GROW(xopts, xopts_nr + 1, xopts_alloc);
187 xopts[xopts_nr++] = xstrdup(arg);
188 return 0;
191 static int option_parse_n(const struct option *opt,
192 const char *arg, int unset)
194 show_diffstat = unset;
195 return 0;
198 static struct option builtin_merge_options[] = {
199 { OPTION_CALLBACK, 'n', NULL, NULL, NULL,
200 N_("do not show a diffstat at the end of the merge"),
201 PARSE_OPT_NOARG, option_parse_n },
202 OPT_BOOL(0, "stat", &show_diffstat,
203 N_("show a diffstat at the end of the merge")),
204 OPT_BOOL(0, "summary", &show_diffstat, N_("(synonym to --stat)")),
205 { OPTION_INTEGER, 0, "log", &shortlog_len, N_("n"),
206 N_("add (at most <n>) entries from shortlog to merge commit message"),
207 PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
208 OPT_BOOL(0, "squash", &squash,
209 N_("create a single commit instead of doing a merge")),
210 OPT_BOOL(0, "commit", &option_commit,
211 N_("perform a commit if the merge succeeds (default)")),
212 OPT_BOOL('e', "edit", &option_edit,
213 N_("edit message before committing")),
214 OPT_SET_INT(0, "ff", &fast_forward, N_("allow fast-forward (default)"), FF_ALLOW),
215 { OPTION_SET_INT, 0, "ff-only", &fast_forward, NULL,
216 N_("abort if fast-forward is not possible"),
217 PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, FF_ONLY },
218 OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
219 OPT_BOOL(0, "verify-signatures", &verify_signatures,
220 N_("verify that the named commit has a valid GPG signature")),
221 OPT_CALLBACK('s', "strategy", &use_strategies, N_("strategy"),
222 N_("merge strategy to use"), option_parse_strategy),
223 OPT_CALLBACK('X', "strategy-option", &xopts, N_("option=value"),
224 N_("option for selected merge strategy"), option_parse_x),
225 OPT_CALLBACK('m', "message", &merge_msg, N_("message"),
226 N_("merge commit message (for a non-fast-forward merge)"),
227 option_parse_message),
228 OPT__VERBOSITY(&verbosity),
229 OPT_BOOL(0, "abort", &abort_current_merge,
230 N_("abort the current in-progress merge")),
231 OPT_BOOL(0, "continue", &continue_current_merge,
232 N_("continue the current in-progress merge")),
233 OPT_BOOL(0, "allow-unrelated-histories", &allow_unrelated_histories,
234 N_("allow merging unrelated histories")),
235 OPT_SET_INT(0, "progress", &show_progress, N_("force progress reporting"), 1),
236 { OPTION_STRING, 'S', "gpg-sign", &sign_commit, N_("key-id"),
237 N_("GPG sign commit"), PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
238 OPT_BOOL(0, "overwrite-ignore", &overwrite_ignore, N_("update ignored files (default)")),
239 OPT_BOOL(0, "signoff", &signoff, N_("add Signed-off-by:")),
240 OPT_BOOL(0, "verify", &verify_msg, N_("verify commit-msg hook")),
241 OPT_END()
244 /* Cleans up metadata that is uninteresting after a succeeded merge. */
245 static void drop_save(void)
247 unlink(git_path_merge_head());
248 unlink(git_path_merge_msg());
249 unlink(git_path_merge_mode());
252 static int save_state(struct object_id *stash)
254 int len;
255 struct child_process cp = CHILD_PROCESS_INIT;
256 struct strbuf buffer = STRBUF_INIT;
257 const char *argv[] = {"stash", "create", NULL};
258 int rc = -1;
260 cp.argv = argv;
261 cp.out = -1;
262 cp.git_cmd = 1;
264 if (start_command(&cp))
265 die(_("could not run stash."));
266 len = strbuf_read(&buffer, cp.out, 1024);
267 close(cp.out);
269 if (finish_command(&cp) || len < 0)
270 die(_("stash failed"));
271 else if (!len) /* no changes */
272 goto out;
273 strbuf_setlen(&buffer, buffer.len-1);
274 if (get_oid(buffer.buf, stash))
275 die(_("not a valid object: %s"), buffer.buf);
276 rc = 0;
277 out:
278 strbuf_release(&buffer);
279 return rc;
282 static void read_empty(unsigned const char *sha1, int verbose)
284 int i = 0;
285 const char *args[7];
287 args[i++] = "read-tree";
288 if (verbose)
289 args[i++] = "-v";
290 args[i++] = "-m";
291 args[i++] = "-u";
292 args[i++] = EMPTY_TREE_SHA1_HEX;
293 args[i++] = sha1_to_hex(sha1);
294 args[i] = NULL;
296 if (run_command_v_opt(args, RUN_GIT_CMD))
297 die(_("read-tree failed"));
300 static void reset_hard(unsigned const char *sha1, int verbose)
302 int i = 0;
303 const char *args[6];
305 args[i++] = "read-tree";
306 if (verbose)
307 args[i++] = "-v";
308 args[i++] = "--reset";
309 args[i++] = "-u";
310 args[i++] = sha1_to_hex(sha1);
311 args[i] = NULL;
313 if (run_command_v_opt(args, RUN_GIT_CMD))
314 die(_("read-tree failed"));
317 static void restore_state(const struct object_id *head,
318 const struct object_id *stash)
320 struct strbuf sb = STRBUF_INIT;
321 const char *args[] = { "stash", "apply", NULL, NULL };
323 if (is_null_oid(stash))
324 return;
326 reset_hard(head->hash, 1);
328 args[2] = oid_to_hex(stash);
331 * It is OK to ignore error here, for example when there was
332 * nothing to restore.
334 run_command_v_opt(args, RUN_GIT_CMD);
336 strbuf_release(&sb);
337 refresh_cache(REFRESH_QUIET);
340 /* This is called when no merge was necessary. */
341 static void finish_up_to_date(const char *msg)
343 if (verbosity >= 0)
344 printf("%s%s\n", squash ? _(" (nothing to squash)") : "", msg);
345 drop_save();
348 static void squash_message(struct commit *commit, struct commit_list *remoteheads)
350 struct rev_info rev;
351 struct strbuf out = STRBUF_INIT;
352 struct commit_list *j;
353 struct pretty_print_context ctx = {0};
355 printf(_("Squash commit -- not updating HEAD\n"));
357 init_revisions(&rev, NULL);
358 rev.ignore_merges = 1;
359 rev.commit_format = CMIT_FMT_MEDIUM;
361 commit->object.flags |= UNINTERESTING;
362 add_pending_object(&rev, &commit->object, NULL);
364 for (j = remoteheads; j; j = j->next)
365 add_pending_object(&rev, &j->item->object, NULL);
367 setup_revisions(0, NULL, &rev, NULL);
368 if (prepare_revision_walk(&rev))
369 die(_("revision walk setup failed"));
371 ctx.abbrev = rev.abbrev;
372 ctx.date_mode = rev.date_mode;
373 ctx.fmt = rev.commit_format;
375 strbuf_addstr(&out, "Squashed commit of the following:\n");
376 while ((commit = get_revision(&rev)) != NULL) {
377 strbuf_addch(&out, '\n');
378 strbuf_addf(&out, "commit %s\n",
379 oid_to_hex(&commit->object.oid));
380 pretty_print_commit(&ctx, commit, &out);
382 write_file_buf(git_path_squash_msg(), out.buf, out.len);
383 strbuf_release(&out);
386 static void finish(struct commit *head_commit,
387 struct commit_list *remoteheads,
388 const struct object_id *new_head, const char *msg)
390 struct strbuf reflog_message = STRBUF_INIT;
391 const struct object_id *head = &head_commit->object.oid;
393 if (!msg)
394 strbuf_addstr(&reflog_message, getenv("GIT_REFLOG_ACTION"));
395 else {
396 if (verbosity >= 0)
397 printf("%s\n", msg);
398 strbuf_addf(&reflog_message, "%s: %s",
399 getenv("GIT_REFLOG_ACTION"), msg);
401 if (squash) {
402 squash_message(head_commit, remoteheads);
403 } else {
404 if (verbosity >= 0 && !merge_msg.len)
405 printf(_("No merge message -- not updating HEAD\n"));
406 else {
407 const char *argv_gc_auto[] = { "gc", "--auto", NULL };
408 update_ref(reflog_message.buf, "HEAD", new_head, head,
409 0, UPDATE_REFS_DIE_ON_ERR);
411 * We ignore errors in 'gc --auto', since the
412 * user should see them.
414 close_all_packs();
415 run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
418 if (new_head && show_diffstat) {
419 struct diff_options opts;
420 diff_setup(&opts);
421 opts.stat_width = -1; /* use full terminal width */
422 opts.stat_graph_width = -1; /* respect statGraphWidth config */
423 opts.output_format |=
424 DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
425 opts.detect_rename = DIFF_DETECT_RENAME;
426 diff_setup_done(&opts);
427 diff_tree_oid(head, new_head, "", &opts);
428 diffcore_std(&opts);
429 diff_flush(&opts);
432 /* Run a post-merge hook */
433 run_hook_le(NULL, "post-merge", squash ? "1" : "0", NULL);
435 strbuf_release(&reflog_message);
438 /* Get the name for the merge commit's message. */
439 static void merge_name(const char *remote, struct strbuf *msg)
441 struct commit *remote_head;
442 struct object_id branch_head;
443 struct strbuf buf = STRBUF_INIT;
444 struct strbuf bname = STRBUF_INIT;
445 const char *ptr;
446 char *found_ref;
447 int len, early;
449 strbuf_branchname(&bname, remote, 0);
450 remote = bname.buf;
452 oidclr(&branch_head);
453 remote_head = get_merge_parent(remote);
454 if (!remote_head)
455 die(_("'%s' does not point to a commit"), remote);
457 if (dwim_ref(remote, strlen(remote), &branch_head, &found_ref) > 0) {
458 if (starts_with(found_ref, "refs/heads/")) {
459 strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
460 oid_to_hex(&branch_head), remote);
461 goto cleanup;
463 if (starts_with(found_ref, "refs/tags/")) {
464 strbuf_addf(msg, "%s\t\ttag '%s' of .\n",
465 oid_to_hex(&branch_head), remote);
466 goto cleanup;
468 if (starts_with(found_ref, "refs/remotes/")) {
469 strbuf_addf(msg, "%s\t\tremote-tracking branch '%s' of .\n",
470 oid_to_hex(&branch_head), remote);
471 goto cleanup;
475 /* See if remote matches <name>^^^.. or <name>~<number> */
476 for (len = 0, ptr = remote + strlen(remote);
477 remote < ptr && ptr[-1] == '^';
478 ptr--)
479 len++;
480 if (len)
481 early = 1;
482 else {
483 early = 0;
484 ptr = strrchr(remote, '~');
485 if (ptr) {
486 int seen_nonzero = 0;
488 len++; /* count ~ */
489 while (*++ptr && isdigit(*ptr)) {
490 seen_nonzero |= (*ptr != '0');
491 len++;
493 if (*ptr)
494 len = 0; /* not ...~<number> */
495 else if (seen_nonzero)
496 early = 1;
497 else if (len == 1)
498 early = 1; /* "name~" is "name~1"! */
501 if (len) {
502 struct strbuf truname = STRBUF_INIT;
503 strbuf_addf(&truname, "refs/heads/%s", remote);
504 strbuf_setlen(&truname, truname.len - len);
505 if (ref_exists(truname.buf)) {
506 strbuf_addf(msg,
507 "%s\t\tbranch '%s'%s of .\n",
508 oid_to_hex(&remote_head->object.oid),
509 truname.buf + 11,
510 (early ? " (early part)" : ""));
511 strbuf_release(&truname);
512 goto cleanup;
514 strbuf_release(&truname);
517 if (remote_head->util) {
518 struct merge_remote_desc *desc;
519 desc = merge_remote_util(remote_head);
520 if (desc && desc->obj && desc->obj->type == OBJ_TAG) {
521 strbuf_addf(msg, "%s\t\t%s '%s'\n",
522 oid_to_hex(&desc->obj->oid),
523 typename(desc->obj->type),
524 remote);
525 goto cleanup;
529 strbuf_addf(msg, "%s\t\tcommit '%s'\n",
530 oid_to_hex(&remote_head->object.oid), remote);
531 cleanup:
532 strbuf_release(&buf);
533 strbuf_release(&bname);
536 static void parse_branch_merge_options(char *bmo)
538 const char **argv;
539 int argc;
541 if (!bmo)
542 return;
543 argc = split_cmdline(bmo, &argv);
544 if (argc < 0)
545 die(_("Bad branch.%s.mergeoptions string: %s"), branch,
546 split_cmdline_strerror(argc));
547 REALLOC_ARRAY(argv, argc + 2);
548 MOVE_ARRAY(argv + 1, argv, argc + 1);
549 argc++;
550 argv[0] = "branch.*.mergeoptions";
551 parse_options(argc, argv, NULL, builtin_merge_options,
552 builtin_merge_usage, 0);
553 free(argv);
556 static int git_merge_config(const char *k, const char *v, void *cb)
558 int status;
560 if (branch && starts_with(k, "branch.") &&
561 starts_with(k + 7, branch) &&
562 !strcmp(k + 7 + strlen(branch), ".mergeoptions")) {
563 free(branch_mergeoptions);
564 branch_mergeoptions = xstrdup(v);
565 return 0;
568 if (!strcmp(k, "merge.diffstat") || !strcmp(k, "merge.stat"))
569 show_diffstat = git_config_bool(k, v);
570 else if (!strcmp(k, "merge.verifysignatures"))
571 verify_signatures = git_config_bool(k, v);
572 else if (!strcmp(k, "pull.twohead"))
573 return git_config_string(&pull_twohead, k, v);
574 else if (!strcmp(k, "pull.octopus"))
575 return git_config_string(&pull_octopus, k, v);
576 else if (!strcmp(k, "merge.renormalize"))
577 option_renormalize = git_config_bool(k, v);
578 else if (!strcmp(k, "merge.ff")) {
579 int boolval = git_parse_maybe_bool(v);
580 if (0 <= boolval) {
581 fast_forward = boolval ? FF_ALLOW : FF_NO;
582 } else if (v && !strcmp(v, "only")) {
583 fast_forward = FF_ONLY;
584 } /* do not barf on values from future versions of git */
585 return 0;
586 } else if (!strcmp(k, "merge.defaulttoupstream")) {
587 default_to_upstream = git_config_bool(k, v);
588 return 0;
589 } else if (!strcmp(k, "commit.gpgsign")) {
590 sign_commit = git_config_bool(k, v) ? "" : NULL;
591 return 0;
594 status = fmt_merge_msg_config(k, v, cb);
595 if (status)
596 return status;
597 status = git_gpg_config(k, v, NULL);
598 if (status)
599 return status;
600 return git_diff_ui_config(k, v, cb);
603 static int read_tree_trivial(struct object_id *common, struct object_id *head,
604 struct object_id *one)
606 int i, nr_trees = 0;
607 struct tree *trees[MAX_UNPACK_TREES];
608 struct tree_desc t[MAX_UNPACK_TREES];
609 struct unpack_trees_options opts;
611 memset(&opts, 0, sizeof(opts));
612 opts.head_idx = 2;
613 opts.src_index = &the_index;
614 opts.dst_index = &the_index;
615 opts.update = 1;
616 opts.verbose_update = 1;
617 opts.trivial_merges_only = 1;
618 opts.merge = 1;
619 trees[nr_trees] = parse_tree_indirect(common);
620 if (!trees[nr_trees++])
621 return -1;
622 trees[nr_trees] = parse_tree_indirect(head);
623 if (!trees[nr_trees++])
624 return -1;
625 trees[nr_trees] = parse_tree_indirect(one);
626 if (!trees[nr_trees++])
627 return -1;
628 opts.fn = threeway_merge;
629 cache_tree_free(&active_cache_tree);
630 for (i = 0; i < nr_trees; i++) {
631 parse_tree(trees[i]);
632 init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
634 if (unpack_trees(nr_trees, t, &opts))
635 return -1;
636 return 0;
639 static void write_tree_trivial(struct object_id *oid)
641 if (write_cache_as_tree(oid->hash, 0, NULL))
642 die(_("git write-tree failed to write a tree"));
645 static int try_merge_strategy(const char *strategy, struct commit_list *common,
646 struct commit_list *remoteheads,
647 struct commit *head)
649 static struct lock_file lock;
650 const char *head_arg = "HEAD";
652 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
653 refresh_cache(REFRESH_QUIET);
654 if (active_cache_changed &&
655 write_locked_index(&the_index, &lock, COMMIT_LOCK))
656 return error(_("Unable to write index."));
657 rollback_lock_file(&lock);
659 if (!strcmp(strategy, "recursive") || !strcmp(strategy, "subtree")) {
660 int clean, x;
661 struct commit *result;
662 struct commit_list *reversed = NULL;
663 struct merge_options o;
664 struct commit_list *j;
666 if (remoteheads->next) {
667 error(_("Not handling anything other than two heads merge."));
668 return 2;
671 init_merge_options(&o);
672 if (!strcmp(strategy, "subtree"))
673 o.subtree_shift = "";
675 o.renormalize = option_renormalize;
676 o.show_rename_progress =
677 show_progress == -1 ? isatty(2) : show_progress;
679 for (x = 0; x < xopts_nr; x++)
680 if (parse_merge_opt(&o, xopts[x]))
681 die(_("Unknown option for merge-recursive: -X%s"), xopts[x]);
683 o.branch1 = head_arg;
684 o.branch2 = merge_remote_util(remoteheads->item)->name;
686 for (j = common; j; j = j->next)
687 commit_list_insert(j->item, &reversed);
689 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
690 clean = merge_recursive(&o, head,
691 remoteheads->item, reversed, &result);
692 if (clean < 0)
693 exit(128);
694 if (active_cache_changed &&
695 write_locked_index(&the_index, &lock, COMMIT_LOCK))
696 die (_("unable to write %s"), get_index_file());
697 rollback_lock_file(&lock);
698 return clean ? 0 : 1;
699 } else {
700 return try_merge_command(strategy, xopts_nr, xopts,
701 common, head_arg, remoteheads);
705 static void count_diff_files(struct diff_queue_struct *q,
706 struct diff_options *opt, void *data)
708 int *count = data;
710 (*count) += q->nr;
713 static int count_unmerged_entries(void)
715 int i, ret = 0;
717 for (i = 0; i < active_nr; i++)
718 if (ce_stage(active_cache[i]))
719 ret++;
721 return ret;
724 static void add_strategies(const char *string, unsigned attr)
726 int i;
728 if (string) {
729 struct string_list list = STRING_LIST_INIT_DUP;
730 struct string_list_item *item;
731 string_list_split(&list, string, ' ', -1);
732 for_each_string_list_item(item, &list)
733 append_strategy(get_strategy(item->string));
734 string_list_clear(&list, 0);
735 return;
737 for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
738 if (all_strategy[i].attr & attr)
739 append_strategy(&all_strategy[i]);
743 static void read_merge_msg(struct strbuf *msg)
745 const char *filename = git_path_merge_msg();
746 strbuf_reset(msg);
747 if (strbuf_read_file(msg, filename, 0) < 0)
748 die_errno(_("Could not read from '%s'"), filename);
751 static void write_merge_state(struct commit_list *);
752 static void abort_commit(struct commit_list *remoteheads, const char *err_msg)
754 if (err_msg)
755 error("%s", err_msg);
756 fprintf(stderr,
757 _("Not committing merge; use 'git commit' to complete the merge.\n"));
758 write_merge_state(remoteheads);
759 exit(1);
762 static const char merge_editor_comment[] =
763 N_("Please enter a commit message to explain why this merge is necessary,\n"
764 "especially if it merges an updated upstream into a topic branch.\n"
765 "\n"
766 "Lines starting with '%c' will be ignored, and an empty message aborts\n"
767 "the commit.\n");
769 static void write_merge_heads(struct commit_list *);
770 static void prepare_to_commit(struct commit_list *remoteheads)
772 struct strbuf msg = STRBUF_INIT;
773 strbuf_addbuf(&msg, &merge_msg);
774 strbuf_addch(&msg, '\n');
775 if (squash)
776 BUG("the control must not reach here under --squash");
777 if (0 < option_edit)
778 strbuf_commented_addf(&msg, _(merge_editor_comment), comment_line_char);
779 if (signoff)
780 append_signoff(&msg, ignore_non_trailer(msg.buf, msg.len), 0);
781 write_merge_heads(remoteheads);
782 write_file_buf(git_path_merge_msg(), msg.buf, msg.len);
783 if (run_commit_hook(0 < option_edit, get_index_file(), "prepare-commit-msg",
784 git_path_merge_msg(), "merge", NULL))
785 abort_commit(remoteheads, NULL);
786 if (0 < option_edit) {
787 if (launch_editor(git_path_merge_msg(), NULL, NULL))
788 abort_commit(remoteheads, NULL);
791 if (verify_msg && run_commit_hook(0 < option_edit, get_index_file(),
792 "commit-msg",
793 git_path_merge_msg(), NULL))
794 abort_commit(remoteheads, NULL);
796 read_merge_msg(&msg);
797 strbuf_stripspace(&msg, 0 < option_edit);
798 if (!msg.len)
799 abort_commit(remoteheads, _("Empty commit message."));
800 strbuf_release(&merge_msg);
801 strbuf_addbuf(&merge_msg, &msg);
802 strbuf_release(&msg);
805 static int merge_trivial(struct commit *head, struct commit_list *remoteheads)
807 struct object_id result_tree, result_commit;
808 struct commit_list *parents, **pptr = &parents;
809 static struct lock_file lock;
811 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
812 refresh_cache(REFRESH_QUIET);
813 if (active_cache_changed &&
814 write_locked_index(&the_index, &lock, COMMIT_LOCK))
815 return error(_("Unable to write index."));
816 rollback_lock_file(&lock);
818 write_tree_trivial(&result_tree);
819 printf(_("Wonderful.\n"));
820 pptr = commit_list_append(head, pptr);
821 pptr = commit_list_append(remoteheads->item, pptr);
822 prepare_to_commit(remoteheads);
823 if (commit_tree(merge_msg.buf, merge_msg.len, result_tree.hash, parents,
824 result_commit.hash, NULL, sign_commit))
825 die(_("failed to write commit object"));
826 finish(head, remoteheads, &result_commit, "In-index merge");
827 drop_save();
828 return 0;
831 static int finish_automerge(struct commit *head,
832 int head_subsumed,
833 struct commit_list *common,
834 struct commit_list *remoteheads,
835 struct object_id *result_tree,
836 const char *wt_strategy)
838 struct commit_list *parents = NULL;
839 struct strbuf buf = STRBUF_INIT;
840 struct object_id result_commit;
842 free_commit_list(common);
843 parents = remoteheads;
844 if (!head_subsumed || fast_forward == FF_NO)
845 commit_list_insert(head, &parents);
846 strbuf_addch(&merge_msg, '\n');
847 prepare_to_commit(remoteheads);
848 if (commit_tree(merge_msg.buf, merge_msg.len, result_tree->hash, parents,
849 result_commit.hash, NULL, sign_commit))
850 die(_("failed to write commit object"));
851 strbuf_addf(&buf, "Merge made by the '%s' strategy.", wt_strategy);
852 finish(head, remoteheads, &result_commit, buf.buf);
853 strbuf_release(&buf);
854 drop_save();
855 return 0;
858 static int suggest_conflicts(void)
860 const char *filename;
861 FILE *fp;
862 struct strbuf msgbuf = STRBUF_INIT;
864 filename = git_path_merge_msg();
865 fp = xfopen(filename, "a");
867 append_conflicts_hint(&msgbuf);
868 fputs(msgbuf.buf, fp);
869 strbuf_release(&msgbuf);
870 fclose(fp);
871 rerere(allow_rerere_auto);
872 printf(_("Automatic merge failed; "
873 "fix conflicts and then commit the result.\n"));
874 return 1;
877 static int evaluate_result(void)
879 int cnt = 0;
880 struct rev_info rev;
882 /* Check how many files differ. */
883 init_revisions(&rev, "");
884 setup_revisions(0, NULL, &rev, NULL);
885 rev.diffopt.output_format |=
886 DIFF_FORMAT_CALLBACK;
887 rev.diffopt.format_callback = count_diff_files;
888 rev.diffopt.format_callback_data = &cnt;
889 run_diff_files(&rev, 0);
892 * Check how many unmerged entries are
893 * there.
895 cnt += count_unmerged_entries();
897 return cnt;
901 * Pretend as if the user told us to merge with the remote-tracking
902 * branch we have for the upstream of the current branch
904 static int setup_with_upstream(const char ***argv)
906 struct branch *branch = branch_get(NULL);
907 int i;
908 const char **args;
910 if (!branch)
911 die(_("No current branch."));
912 if (!branch->remote_name)
913 die(_("No remote for the current branch."));
914 if (!branch->merge_nr)
915 die(_("No default upstream defined for the current branch."));
917 args = xcalloc(st_add(branch->merge_nr, 1), sizeof(char *));
918 for (i = 0; i < branch->merge_nr; i++) {
919 if (!branch->merge[i]->dst)
920 die(_("No remote-tracking branch for %s from %s"),
921 branch->merge[i]->src, branch->remote_name);
922 args[i] = branch->merge[i]->dst;
924 args[i] = NULL;
925 *argv = args;
926 return i;
929 static void write_merge_heads(struct commit_list *remoteheads)
931 struct commit_list *j;
932 struct strbuf buf = STRBUF_INIT;
934 for (j = remoteheads; j; j = j->next) {
935 struct object_id *oid;
936 struct commit *c = j->item;
937 if (c->util && merge_remote_util(c)->obj) {
938 oid = &merge_remote_util(c)->obj->oid;
939 } else {
940 oid = &c->object.oid;
942 strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
944 write_file_buf(git_path_merge_head(), buf.buf, buf.len);
946 strbuf_reset(&buf);
947 if (fast_forward == FF_NO)
948 strbuf_addstr(&buf, "no-ff");
949 write_file_buf(git_path_merge_mode(), buf.buf, buf.len);
950 strbuf_release(&buf);
953 static void write_merge_state(struct commit_list *remoteheads)
955 write_merge_heads(remoteheads);
956 strbuf_addch(&merge_msg, '\n');
957 write_file_buf(git_path_merge_msg(), merge_msg.buf, merge_msg.len);
960 static int default_edit_option(void)
962 static const char name[] = "GIT_MERGE_AUTOEDIT";
963 const char *e = getenv(name);
964 struct stat st_stdin, st_stdout;
966 if (have_message)
967 /* an explicit -m msg without --[no-]edit */
968 return 0;
970 if (e) {
971 int v = git_parse_maybe_bool(e);
972 if (v < 0)
973 die(_("Bad value '%s' in environment '%s'"), e, name);
974 return v;
977 /* Use editor if stdin and stdout are the same and is a tty */
978 return (!fstat(0, &st_stdin) &&
979 !fstat(1, &st_stdout) &&
980 isatty(0) && isatty(1) &&
981 st_stdin.st_dev == st_stdout.st_dev &&
982 st_stdin.st_ino == st_stdout.st_ino &&
983 st_stdin.st_mode == st_stdout.st_mode);
986 static struct commit_list *reduce_parents(struct commit *head_commit,
987 int *head_subsumed,
988 struct commit_list *remoteheads)
990 struct commit_list *parents, **remotes;
993 * Is the current HEAD reachable from another commit being
994 * merged? If so we do not want to record it as a parent of
995 * the resulting merge, unless --no-ff is given. We will flip
996 * this variable to 0 when we find HEAD among the independent
997 * tips being merged.
999 *head_subsumed = 1;
1001 /* Find what parents to record by checking independent ones. */
1002 parents = reduce_heads(remoteheads);
1003 free_commit_list(remoteheads);
1005 remoteheads = NULL;
1006 remotes = &remoteheads;
1007 while (parents) {
1008 struct commit *commit = pop_commit(&parents);
1009 if (commit == head_commit)
1010 *head_subsumed = 0;
1011 else
1012 remotes = &commit_list_insert(commit, remotes)->next;
1014 return remoteheads;
1017 static void prepare_merge_message(struct strbuf *merge_names, struct strbuf *merge_msg)
1019 struct fmt_merge_msg_opts opts;
1021 memset(&opts, 0, sizeof(opts));
1022 opts.add_title = !have_message;
1023 opts.shortlog_len = shortlog_len;
1024 opts.credit_people = (0 < option_edit);
1026 fmt_merge_msg(merge_names, merge_msg, &opts);
1027 if (merge_msg->len)
1028 strbuf_setlen(merge_msg, merge_msg->len - 1);
1031 static void handle_fetch_head(struct commit_list **remotes, struct strbuf *merge_names)
1033 const char *filename;
1034 int fd, pos, npos;
1035 struct strbuf fetch_head_file = STRBUF_INIT;
1037 if (!merge_names)
1038 merge_names = &fetch_head_file;
1040 filename = git_path_fetch_head();
1041 fd = open(filename, O_RDONLY);
1042 if (fd < 0)
1043 die_errno(_("could not open '%s' for reading"), filename);
1045 if (strbuf_read(merge_names, fd, 0) < 0)
1046 die_errno(_("could not read '%s'"), filename);
1047 if (close(fd) < 0)
1048 die_errno(_("could not close '%s'"), filename);
1050 for (pos = 0; pos < merge_names->len; pos = npos) {
1051 struct object_id oid;
1052 char *ptr;
1053 struct commit *commit;
1055 ptr = strchr(merge_names->buf + pos, '\n');
1056 if (ptr)
1057 npos = ptr - merge_names->buf + 1;
1058 else
1059 npos = merge_names->len;
1061 if (npos - pos < GIT_SHA1_HEXSZ + 2 ||
1062 get_oid_hex(merge_names->buf + pos, &oid))
1063 commit = NULL; /* bad */
1064 else if (memcmp(merge_names->buf + pos + GIT_SHA1_HEXSZ, "\t\t", 2))
1065 continue; /* not-for-merge */
1066 else {
1067 char saved = merge_names->buf[pos + GIT_SHA1_HEXSZ];
1068 merge_names->buf[pos + GIT_SHA1_HEXSZ] = '\0';
1069 commit = get_merge_parent(merge_names->buf + pos);
1070 merge_names->buf[pos + GIT_SHA1_HEXSZ] = saved;
1072 if (!commit) {
1073 if (ptr)
1074 *ptr = '\0';
1075 die(_("not something we can merge in %s: %s"),
1076 filename, merge_names->buf + pos);
1078 remotes = &commit_list_insert(commit, remotes)->next;
1081 if (merge_names == &fetch_head_file)
1082 strbuf_release(&fetch_head_file);
1085 static struct commit_list *collect_parents(struct commit *head_commit,
1086 int *head_subsumed,
1087 int argc, const char **argv,
1088 struct strbuf *merge_msg)
1090 int i;
1091 struct commit_list *remoteheads = NULL;
1092 struct commit_list **remotes = &remoteheads;
1093 struct strbuf merge_names = STRBUF_INIT, *autogen = NULL;
1095 if (merge_msg && (!have_message || shortlog_len))
1096 autogen = &merge_names;
1098 if (head_commit)
1099 remotes = &commit_list_insert(head_commit, remotes)->next;
1101 if (argc == 1 && !strcmp(argv[0], "FETCH_HEAD")) {
1102 handle_fetch_head(remotes, autogen);
1103 remoteheads = reduce_parents(head_commit, head_subsumed, remoteheads);
1104 } else {
1105 for (i = 0; i < argc; i++) {
1106 struct commit *commit = get_merge_parent(argv[i]);
1107 if (!commit)
1108 help_unknown_ref(argv[i], "merge",
1109 _("not something we can merge"));
1110 remotes = &commit_list_insert(commit, remotes)->next;
1112 remoteheads = reduce_parents(head_commit, head_subsumed, remoteheads);
1113 if (autogen) {
1114 struct commit_list *p;
1115 for (p = remoteheads; p; p = p->next)
1116 merge_name(merge_remote_util(p->item)->name, autogen);
1120 if (autogen) {
1121 prepare_merge_message(autogen, merge_msg);
1122 strbuf_release(autogen);
1125 return remoteheads;
1128 int cmd_merge(int argc, const char **argv, const char *prefix)
1130 struct object_id result_tree, stash, head_oid;
1131 struct commit *head_commit;
1132 struct strbuf buf = STRBUF_INIT;
1133 int i, ret = 0, head_subsumed;
1134 int best_cnt = -1, merge_was_ok = 0, automerge_was_ok = 0;
1135 struct commit_list *common = NULL;
1136 const char *best_strategy = NULL, *wt_strategy = NULL;
1137 struct commit_list *remoteheads, *p;
1138 void *branch_to_free;
1139 int orig_argc = argc;
1141 if (argc == 2 && !strcmp(argv[1], "-h"))
1142 usage_with_options(builtin_merge_usage, builtin_merge_options);
1145 * Check if we are _not_ on a detached HEAD, i.e. if there is a
1146 * current branch.
1148 branch = branch_to_free = resolve_refdup("HEAD", 0, &head_oid, NULL);
1149 if (branch)
1150 skip_prefix(branch, "refs/heads/", &branch);
1151 if (!branch || is_null_oid(&head_oid))
1152 head_commit = NULL;
1153 else
1154 head_commit = lookup_commit_or_die(&head_oid, "HEAD");
1156 init_diff_ui_defaults();
1157 git_config(git_merge_config, NULL);
1159 if (branch_mergeoptions)
1160 parse_branch_merge_options(branch_mergeoptions);
1161 argc = parse_options(argc, argv, prefix, builtin_merge_options,
1162 builtin_merge_usage, 0);
1163 if (shortlog_len < 0)
1164 shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
1166 if (verbosity < 0 && show_progress == -1)
1167 show_progress = 0;
1169 if (abort_current_merge) {
1170 int nargc = 2;
1171 const char *nargv[] = {"reset", "--merge", NULL};
1173 if (orig_argc != 2)
1174 usage_msg_opt(_("--abort expects no arguments"),
1175 builtin_merge_usage, builtin_merge_options);
1177 if (!file_exists(git_path_merge_head()))
1178 die(_("There is no merge to abort (MERGE_HEAD missing)."));
1180 /* Invoke 'git reset --merge' */
1181 ret = cmd_reset(nargc, nargv, prefix);
1182 goto done;
1185 if (continue_current_merge) {
1186 int nargc = 1;
1187 const char *nargv[] = {"commit", NULL};
1189 if (orig_argc != 2)
1190 usage_msg_opt(_("--continue expects no arguments"),
1191 builtin_merge_usage, builtin_merge_options);
1193 if (!file_exists(git_path_merge_head()))
1194 die(_("There is no merge in progress (MERGE_HEAD missing)."));
1196 /* Invoke 'git commit' */
1197 ret = cmd_commit(nargc, nargv, prefix);
1198 goto done;
1201 if (read_cache_unmerged())
1202 die_resolve_conflict("merge");
1204 if (file_exists(git_path_merge_head())) {
1206 * There is no unmerged entry, don't advise 'git
1207 * add/rm <file>', just 'git commit'.
1209 if (advice_resolve_conflict)
1210 die(_("You have not concluded your merge (MERGE_HEAD exists).\n"
1211 "Please, commit your changes before you merge."));
1212 else
1213 die(_("You have not concluded your merge (MERGE_HEAD exists)."));
1215 if (file_exists(git_path_cherry_pick_head())) {
1216 if (advice_resolve_conflict)
1217 die(_("You have not concluded your cherry-pick (CHERRY_PICK_HEAD exists).\n"
1218 "Please, commit your changes before you merge."));
1219 else
1220 die(_("You have not concluded your cherry-pick (CHERRY_PICK_HEAD exists)."));
1222 resolve_undo_clear();
1224 if (verbosity < 0)
1225 show_diffstat = 0;
1227 if (squash) {
1228 if (fast_forward == FF_NO)
1229 die(_("You cannot combine --squash with --no-ff."));
1230 option_commit = 0;
1233 if (!argc) {
1234 if (default_to_upstream)
1235 argc = setup_with_upstream(&argv);
1236 else
1237 die(_("No commit specified and merge.defaultToUpstream not set."));
1238 } else if (argc == 1 && !strcmp(argv[0], "-")) {
1239 argv[0] = "@{-1}";
1242 if (!argc)
1243 usage_with_options(builtin_merge_usage,
1244 builtin_merge_options);
1246 if (!head_commit) {
1248 * If the merged head is a valid one there is no reason
1249 * to forbid "git merge" into a branch yet to be born.
1250 * We do the same for "git pull".
1252 struct object_id *remote_head_oid;
1253 if (squash)
1254 die(_("Squash commit into empty head not supported yet"));
1255 if (fast_forward == FF_NO)
1256 die(_("Non-fast-forward commit does not make sense into "
1257 "an empty head"));
1258 remoteheads = collect_parents(head_commit, &head_subsumed,
1259 argc, argv, NULL);
1260 if (!remoteheads)
1261 die(_("%s - not something we can merge"), argv[0]);
1262 if (remoteheads->next)
1263 die(_("Can merge only exactly one commit into empty head"));
1264 remote_head_oid = &remoteheads->item->object.oid;
1265 read_empty(remote_head_oid->hash, 0);
1266 update_ref("initial pull", "HEAD", remote_head_oid, NULL, 0,
1267 UPDATE_REFS_DIE_ON_ERR);
1268 goto done;
1272 * All the rest are the commits being merged; prepare
1273 * the standard merge summary message to be appended
1274 * to the given message.
1276 remoteheads = collect_parents(head_commit, &head_subsumed,
1277 argc, argv, &merge_msg);
1279 if (!head_commit || !argc)
1280 usage_with_options(builtin_merge_usage,
1281 builtin_merge_options);
1283 if (verify_signatures) {
1284 for (p = remoteheads; p; p = p->next) {
1285 struct commit *commit = p->item;
1286 char hex[GIT_MAX_HEXSZ + 1];
1287 struct signature_check signature_check;
1288 memset(&signature_check, 0, sizeof(signature_check));
1290 check_commit_signature(commit, &signature_check);
1292 find_unique_abbrev_r(hex, commit->object.oid.hash, DEFAULT_ABBREV);
1293 switch (signature_check.result) {
1294 case 'G':
1295 break;
1296 case 'U':
1297 die(_("Commit %s has an untrusted GPG signature, "
1298 "allegedly by %s."), hex, signature_check.signer);
1299 case 'B':
1300 die(_("Commit %s has a bad GPG signature "
1301 "allegedly by %s."), hex, signature_check.signer);
1302 default: /* 'N' */
1303 die(_("Commit %s does not have a GPG signature."), hex);
1305 if (verbosity >= 0 && signature_check.result == 'G')
1306 printf(_("Commit %s has a good GPG signature by %s\n"),
1307 hex, signature_check.signer);
1309 signature_check_clear(&signature_check);
1313 strbuf_addstr(&buf, "merge");
1314 for (p = remoteheads; p; p = p->next)
1315 strbuf_addf(&buf, " %s", merge_remote_util(p->item)->name);
1316 setenv("GIT_REFLOG_ACTION", buf.buf, 0);
1317 strbuf_reset(&buf);
1319 for (p = remoteheads; p; p = p->next) {
1320 struct commit *commit = p->item;
1321 strbuf_addf(&buf, "GITHEAD_%s",
1322 oid_to_hex(&commit->object.oid));
1323 setenv(buf.buf, merge_remote_util(commit)->name, 1);
1324 strbuf_reset(&buf);
1325 if (fast_forward != FF_ONLY &&
1326 merge_remote_util(commit) &&
1327 merge_remote_util(commit)->obj &&
1328 merge_remote_util(commit)->obj->type == OBJ_TAG)
1329 fast_forward = FF_NO;
1332 if (option_edit < 0)
1333 option_edit = default_edit_option();
1335 if (!use_strategies) {
1336 if (!remoteheads)
1337 ; /* already up-to-date */
1338 else if (!remoteheads->next)
1339 add_strategies(pull_twohead, DEFAULT_TWOHEAD);
1340 else
1341 add_strategies(pull_octopus, DEFAULT_OCTOPUS);
1344 for (i = 0; i < use_strategies_nr; i++) {
1345 if (use_strategies[i]->attr & NO_FAST_FORWARD)
1346 fast_forward = FF_NO;
1347 if (use_strategies[i]->attr & NO_TRIVIAL)
1348 allow_trivial = 0;
1351 if (!remoteheads)
1352 ; /* already up-to-date */
1353 else if (!remoteheads->next)
1354 common = get_merge_bases(head_commit, remoteheads->item);
1355 else {
1356 struct commit_list *list = remoteheads;
1357 commit_list_insert(head_commit, &list);
1358 common = get_octopus_merge_bases(list);
1359 free(list);
1362 update_ref("updating ORIG_HEAD", "ORIG_HEAD",
1363 &head_commit->object.oid, NULL, 0, UPDATE_REFS_DIE_ON_ERR);
1365 if (remoteheads && !common) {
1366 /* No common ancestors found. */
1367 if (!allow_unrelated_histories)
1368 die(_("refusing to merge unrelated histories"));
1369 /* otherwise, we need a real merge. */
1370 } else if (!remoteheads ||
1371 (!remoteheads->next && !common->next &&
1372 common->item == remoteheads->item)) {
1374 * If head can reach all the merge then we are up to date.
1375 * but first the most common case of merging one remote.
1377 finish_up_to_date(_("Already up to date."));
1378 goto done;
1379 } else if (fast_forward != FF_NO && !remoteheads->next &&
1380 !common->next &&
1381 !oidcmp(&common->item->object.oid, &head_commit->object.oid)) {
1382 /* Again the most common case of merging one remote. */
1383 struct strbuf msg = STRBUF_INIT;
1384 struct commit *commit;
1386 if (verbosity >= 0) {
1387 printf(_("Updating %s..%s\n"),
1388 find_unique_abbrev(head_commit->object.oid.hash,
1389 DEFAULT_ABBREV),
1390 find_unique_abbrev(remoteheads->item->object.oid.hash,
1391 DEFAULT_ABBREV));
1393 strbuf_addstr(&msg, "Fast-forward");
1394 if (have_message)
1395 strbuf_addstr(&msg,
1396 " (no commit created; -m option ignored)");
1397 commit = remoteheads->item;
1398 if (!commit) {
1399 ret = 1;
1400 goto done;
1403 if (checkout_fast_forward(&head_commit->object.oid,
1404 &commit->object.oid,
1405 overwrite_ignore)) {
1406 ret = 1;
1407 goto done;
1410 finish(head_commit, remoteheads, &commit->object.oid, msg.buf);
1411 drop_save();
1412 goto done;
1413 } else if (!remoteheads->next && common->next)
1416 * We are not doing octopus and not fast-forward. Need
1417 * a real merge.
1419 else if (!remoteheads->next && !common->next && option_commit) {
1421 * We are not doing octopus, not fast-forward, and have
1422 * only one common.
1424 refresh_cache(REFRESH_QUIET);
1425 if (allow_trivial && fast_forward != FF_ONLY) {
1426 /* See if it is really trivial. */
1427 git_committer_info(IDENT_STRICT);
1428 printf(_("Trying really trivial in-index merge...\n"));
1429 if (!read_tree_trivial(&common->item->object.oid,
1430 &head_commit->object.oid,
1431 &remoteheads->item->object.oid)) {
1432 ret = merge_trivial(head_commit, remoteheads);
1433 goto done;
1435 printf(_("Nope.\n"));
1437 } else {
1439 * An octopus. If we can reach all the remote we are up
1440 * to date.
1442 int up_to_date = 1;
1443 struct commit_list *j;
1445 for (j = remoteheads; j; j = j->next) {
1446 struct commit_list *common_one;
1449 * Here we *have* to calculate the individual
1450 * merge_bases again, otherwise "git merge HEAD^
1451 * HEAD^^" would be missed.
1453 common_one = get_merge_bases(head_commit, j->item);
1454 if (oidcmp(&common_one->item->object.oid, &j->item->object.oid)) {
1455 up_to_date = 0;
1456 break;
1459 if (up_to_date) {
1460 finish_up_to_date(_("Already up to date. Yeeah!"));
1461 goto done;
1465 if (fast_forward == FF_ONLY)
1466 die(_("Not possible to fast-forward, aborting."));
1468 /* We are going to make a new commit. */
1469 git_committer_info(IDENT_STRICT);
1472 * At this point, we need a real merge. No matter what strategy
1473 * we use, it would operate on the index, possibly affecting the
1474 * working tree, and when resolved cleanly, have the desired
1475 * tree in the index -- this means that the index must be in
1476 * sync with the head commit. The strategies are responsible
1477 * to ensure this.
1479 if (use_strategies_nr == 1 ||
1481 * Stash away the local changes so that we can try more than one.
1483 save_state(&stash))
1484 oidclr(&stash);
1486 for (i = 0; i < use_strategies_nr; i++) {
1487 int ret;
1488 if (i) {
1489 printf(_("Rewinding the tree to pristine...\n"));
1490 restore_state(&head_commit->object.oid, &stash);
1492 if (use_strategies_nr != 1)
1493 printf(_("Trying merge strategy %s...\n"),
1494 use_strategies[i]->name);
1496 * Remember which strategy left the state in the working
1497 * tree.
1499 wt_strategy = use_strategies[i]->name;
1501 ret = try_merge_strategy(use_strategies[i]->name,
1502 common, remoteheads,
1503 head_commit);
1504 if (!option_commit && !ret) {
1505 merge_was_ok = 1;
1507 * This is necessary here just to avoid writing
1508 * the tree, but later we will *not* exit with
1509 * status code 1 because merge_was_ok is set.
1511 ret = 1;
1514 if (ret) {
1516 * The backend exits with 1 when conflicts are
1517 * left to be resolved, with 2 when it does not
1518 * handle the given merge at all.
1520 if (ret == 1) {
1521 int cnt = evaluate_result();
1523 if (best_cnt <= 0 || cnt <= best_cnt) {
1524 best_strategy = use_strategies[i]->name;
1525 best_cnt = cnt;
1528 if (merge_was_ok)
1529 break;
1530 else
1531 continue;
1534 /* Automerge succeeded. */
1535 write_tree_trivial(&result_tree);
1536 automerge_was_ok = 1;
1537 break;
1541 * If we have a resulting tree, that means the strategy module
1542 * auto resolved the merge cleanly.
1544 if (automerge_was_ok) {
1545 ret = finish_automerge(head_commit, head_subsumed,
1546 common, remoteheads,
1547 &result_tree, wt_strategy);
1548 goto done;
1552 * Pick the result from the best strategy and have the user fix
1553 * it up.
1555 if (!best_strategy) {
1556 restore_state(&head_commit->object.oid, &stash);
1557 if (use_strategies_nr > 1)
1558 fprintf(stderr,
1559 _("No merge strategy handled the merge.\n"));
1560 else
1561 fprintf(stderr, _("Merge with strategy %s failed.\n"),
1562 use_strategies[0]->name);
1563 ret = 2;
1564 goto done;
1565 } else if (best_strategy == wt_strategy)
1566 ; /* We already have its result in the working tree. */
1567 else {
1568 printf(_("Rewinding the tree to pristine...\n"));
1569 restore_state(&head_commit->object.oid, &stash);
1570 printf(_("Using the %s to prepare resolving by hand.\n"),
1571 best_strategy);
1572 try_merge_strategy(best_strategy, common, remoteheads,
1573 head_commit);
1576 if (squash)
1577 finish(head_commit, remoteheads, NULL, NULL);
1578 else
1579 write_merge_state(remoteheads);
1581 if (merge_was_ok)
1582 fprintf(stderr, _("Automatic merge went well; "
1583 "stopped before committing as requested\n"));
1584 else
1585 ret = suggest_conflicts();
1587 done:
1588 free(branch_to_free);
1589 return ret;