i18n: verify-tag: mark parseopt strings for translation
[git/jnareb-git.git] / builtin / merge.c
blobe9871ab96bffceaf85714906776395881f2af0f7
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 "parse-options.h"
11 #include "builtin.h"
12 #include "run-command.h"
13 #include "diff.h"
14 #include "refs.h"
15 #include "commit.h"
16 #include "diffcore.h"
17 #include "revision.h"
18 #include "unpack-trees.h"
19 #include "cache-tree.h"
20 #include "dir.h"
21 #include "utf8.h"
22 #include "log-tree.h"
23 #include "color.h"
24 #include "rerere.h"
25 #include "help.h"
26 #include "merge-recursive.h"
27 #include "resolve-undo.h"
28 #include "remote.h"
29 #include "fmt-merge-msg.h"
30 #include "gpg-interface.h"
32 #define DEFAULT_TWOHEAD (1<<0)
33 #define DEFAULT_OCTOPUS (1<<1)
34 #define NO_FAST_FORWARD (1<<2)
35 #define NO_TRIVIAL (1<<3)
37 struct strategy {
38 const char *name;
39 unsigned attr;
42 static const char * const builtin_merge_usage[] = {
43 N_("git merge [options] [<commit>...]"),
44 N_("git merge [options] <msg> HEAD <commit>"),
45 N_("git merge --abort"),
46 NULL
49 static int show_diffstat = 1, shortlog_len = -1, squash;
50 static int option_commit = 1, allow_fast_forward = 1;
51 static int fast_forward_only, option_edit = -1;
52 static int allow_trivial = 1, have_message;
53 static int overwrite_ignore = 1;
54 static struct strbuf merge_msg = STRBUF_INIT;
55 static struct strategy **use_strategies;
56 static size_t use_strategies_nr, use_strategies_alloc;
57 static const char **xopts;
58 static size_t xopts_nr, xopts_alloc;
59 static const char *branch;
60 static char *branch_mergeoptions;
61 static int option_renormalize;
62 static int verbosity;
63 static int allow_rerere_auto;
64 static int abort_current_merge;
65 static int show_progress = -1;
66 static int default_to_upstream;
67 static const char *sign_commit;
69 static struct strategy all_strategy[] = {
70 { "recursive", DEFAULT_TWOHEAD | NO_TRIVIAL },
71 { "octopus", DEFAULT_OCTOPUS },
72 { "resolve", 0 },
73 { "ours", NO_FAST_FORWARD | NO_TRIVIAL },
74 { "subtree", NO_FAST_FORWARD | NO_TRIVIAL },
77 static const char *pull_twohead, *pull_octopus;
79 static int option_parse_message(const struct option *opt,
80 const char *arg, int unset)
82 struct strbuf *buf = opt->value;
84 if (unset)
85 strbuf_setlen(buf, 0);
86 else if (arg) {
87 strbuf_addf(buf, "%s%s", buf->len ? "\n\n" : "", arg);
88 have_message = 1;
89 } else
90 return error(_("switch `m' requires a value"));
91 return 0;
94 static struct strategy *get_strategy(const char *name)
96 int i;
97 struct strategy *ret;
98 static struct cmdnames main_cmds, other_cmds;
99 static int loaded;
101 if (!name)
102 return NULL;
104 for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
105 if (!strcmp(name, all_strategy[i].name))
106 return &all_strategy[i];
108 if (!loaded) {
109 struct cmdnames not_strategies;
110 loaded = 1;
112 memset(&not_strategies, 0, sizeof(struct cmdnames));
113 load_command_list("git-merge-", &main_cmds, &other_cmds);
114 for (i = 0; i < main_cmds.cnt; i++) {
115 int j, found = 0;
116 struct cmdname *ent = main_cmds.names[i];
117 for (j = 0; j < ARRAY_SIZE(all_strategy); j++)
118 if (!strncmp(ent->name, all_strategy[j].name, ent->len)
119 && !all_strategy[j].name[ent->len])
120 found = 1;
121 if (!found)
122 add_cmdname(&not_strategies, ent->name, ent->len);
124 exclude_cmds(&main_cmds, &not_strategies);
126 if (!is_in_cmdlist(&main_cmds, name) && !is_in_cmdlist(&other_cmds, name)) {
127 fprintf(stderr, _("Could not find merge strategy '%s'.\n"), name);
128 fprintf(stderr, _("Available strategies are:"));
129 for (i = 0; i < main_cmds.cnt; i++)
130 fprintf(stderr, " %s", main_cmds.names[i]->name);
131 fprintf(stderr, ".\n");
132 if (other_cmds.cnt) {
133 fprintf(stderr, _("Available custom strategies are:"));
134 for (i = 0; i < other_cmds.cnt; i++)
135 fprintf(stderr, " %s", other_cmds.names[i]->name);
136 fprintf(stderr, ".\n");
138 exit(1);
141 ret = xcalloc(1, sizeof(struct strategy));
142 ret->name = xstrdup(name);
143 ret->attr = NO_TRIVIAL;
144 return ret;
147 static void append_strategy(struct strategy *s)
149 ALLOC_GROW(use_strategies, use_strategies_nr + 1, use_strategies_alloc);
150 use_strategies[use_strategies_nr++] = s;
153 static int option_parse_strategy(const struct option *opt,
154 const char *name, int unset)
156 if (unset)
157 return 0;
159 append_strategy(get_strategy(name));
160 return 0;
163 static int option_parse_x(const struct option *opt,
164 const char *arg, int unset)
166 if (unset)
167 return 0;
169 ALLOC_GROW(xopts, xopts_nr + 1, xopts_alloc);
170 xopts[xopts_nr++] = xstrdup(arg);
171 return 0;
174 static int option_parse_n(const struct option *opt,
175 const char *arg, int unset)
177 show_diffstat = unset;
178 return 0;
181 static struct option builtin_merge_options[] = {
182 { OPTION_CALLBACK, 'n', NULL, NULL, NULL,
183 N_("do not show a diffstat at the end of the merge"),
184 PARSE_OPT_NOARG, option_parse_n },
185 OPT_BOOLEAN(0, "stat", &show_diffstat,
186 N_("show a diffstat at the end of the merge")),
187 OPT_BOOLEAN(0, "summary", &show_diffstat, N_("(synonym to --stat)")),
188 { OPTION_INTEGER, 0, "log", &shortlog_len, N_("n"),
189 N_("add (at most <n>) entries from shortlog to merge commit message"),
190 PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
191 OPT_BOOLEAN(0, "squash", &squash,
192 N_("create a single commit instead of doing a merge")),
193 OPT_BOOLEAN(0, "commit", &option_commit,
194 N_("perform a commit if the merge succeeds (default)")),
195 OPT_BOOL('e', "edit", &option_edit,
196 N_("edit message before committing")),
197 OPT_BOOLEAN(0, "ff", &allow_fast_forward,
198 N_("allow fast-forward (default)")),
199 OPT_BOOLEAN(0, "ff-only", &fast_forward_only,
200 N_("abort if fast-forward is not possible")),
201 OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
202 OPT_CALLBACK('s', "strategy", &use_strategies, N_("strategy"),
203 N_("merge strategy to use"), option_parse_strategy),
204 OPT_CALLBACK('X', "strategy-option", &xopts, N_("option=value"),
205 N_("option for selected merge strategy"), option_parse_x),
206 OPT_CALLBACK('m', "message", &merge_msg, N_("message"),
207 N_("merge commit message (for a non-fast-forward merge)"),
208 option_parse_message),
209 OPT__VERBOSITY(&verbosity),
210 OPT_BOOLEAN(0, "abort", &abort_current_merge,
211 N_("abort the current in-progress merge")),
212 OPT_SET_INT(0, "progress", &show_progress, N_("force progress reporting"), 1),
213 { OPTION_STRING, 'S', "gpg-sign", &sign_commit, N_("key id"),
214 N_("GPG sign commit"), PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
215 OPT_BOOLEAN(0, "overwrite-ignore", &overwrite_ignore, N_("update ignored files (default)")),
216 OPT_END()
219 /* Cleans up metadata that is uninteresting after a succeeded merge. */
220 static void drop_save(void)
222 unlink(git_path("MERGE_HEAD"));
223 unlink(git_path("MERGE_MSG"));
224 unlink(git_path("MERGE_MODE"));
227 static int save_state(unsigned char *stash)
229 int len;
230 struct child_process cp;
231 struct strbuf buffer = STRBUF_INIT;
232 const char *argv[] = {"stash", "create", NULL};
234 memset(&cp, 0, sizeof(cp));
235 cp.argv = argv;
236 cp.out = -1;
237 cp.git_cmd = 1;
239 if (start_command(&cp))
240 die(_("could not run stash."));
241 len = strbuf_read(&buffer, cp.out, 1024);
242 close(cp.out);
244 if (finish_command(&cp) || len < 0)
245 die(_("stash failed"));
246 else if (!len) /* no changes */
247 return -1;
248 strbuf_setlen(&buffer, buffer.len-1);
249 if (get_sha1(buffer.buf, stash))
250 die(_("not a valid object: %s"), buffer.buf);
251 return 0;
254 static void read_empty(unsigned const char *sha1, int verbose)
256 int i = 0;
257 const char *args[7];
259 args[i++] = "read-tree";
260 if (verbose)
261 args[i++] = "-v";
262 args[i++] = "-m";
263 args[i++] = "-u";
264 args[i++] = EMPTY_TREE_SHA1_HEX;
265 args[i++] = sha1_to_hex(sha1);
266 args[i] = NULL;
268 if (run_command_v_opt(args, RUN_GIT_CMD))
269 die(_("read-tree failed"));
272 static void reset_hard(unsigned const char *sha1, int verbose)
274 int i = 0;
275 const char *args[6];
277 args[i++] = "read-tree";
278 if (verbose)
279 args[i++] = "-v";
280 args[i++] = "--reset";
281 args[i++] = "-u";
282 args[i++] = sha1_to_hex(sha1);
283 args[i] = NULL;
285 if (run_command_v_opt(args, RUN_GIT_CMD))
286 die(_("read-tree failed"));
289 static void restore_state(const unsigned char *head,
290 const unsigned char *stash)
292 struct strbuf sb = STRBUF_INIT;
293 const char *args[] = { "stash", "apply", NULL, NULL };
295 if (is_null_sha1(stash))
296 return;
298 reset_hard(head, 1);
300 args[2] = sha1_to_hex(stash);
303 * It is OK to ignore error here, for example when there was
304 * nothing to restore.
306 run_command_v_opt(args, RUN_GIT_CMD);
308 strbuf_release(&sb);
309 refresh_cache(REFRESH_QUIET);
312 /* This is called when no merge was necessary. */
313 static void finish_up_to_date(const char *msg)
315 if (verbosity >= 0)
316 printf("%s%s\n", squash ? _(" (nothing to squash)") : "", msg);
317 drop_save();
320 static void squash_message(struct commit *commit, struct commit_list *remoteheads)
322 struct rev_info rev;
323 struct strbuf out = STRBUF_INIT;
324 struct commit_list *j;
325 const char *filename;
326 int fd;
327 struct pretty_print_context ctx = {0};
329 printf(_("Squash commit -- not updating HEAD\n"));
330 filename = git_path("SQUASH_MSG");
331 fd = open(filename, O_WRONLY | O_CREAT, 0666);
332 if (fd < 0)
333 die_errno(_("Could not write to '%s'"), filename);
335 init_revisions(&rev, NULL);
336 rev.ignore_merges = 1;
337 rev.commit_format = CMIT_FMT_MEDIUM;
339 commit->object.flags |= UNINTERESTING;
340 add_pending_object(&rev, &commit->object, NULL);
342 for (j = remoteheads; j; j = j->next)
343 add_pending_object(&rev, &j->item->object, NULL);
345 setup_revisions(0, NULL, &rev, NULL);
346 if (prepare_revision_walk(&rev))
347 die(_("revision walk setup failed"));
349 ctx.abbrev = rev.abbrev;
350 ctx.date_mode = rev.date_mode;
351 ctx.fmt = rev.commit_format;
353 strbuf_addstr(&out, "Squashed commit of the following:\n");
354 while ((commit = get_revision(&rev)) != NULL) {
355 strbuf_addch(&out, '\n');
356 strbuf_addf(&out, "commit %s\n",
357 sha1_to_hex(commit->object.sha1));
358 pretty_print_commit(&ctx, commit, &out);
360 if (write(fd, out.buf, out.len) < 0)
361 die_errno(_("Writing SQUASH_MSG"));
362 if (close(fd))
363 die_errno(_("Finishing SQUASH_MSG"));
364 strbuf_release(&out);
367 static void finish(struct commit *head_commit,
368 struct commit_list *remoteheads,
369 const unsigned char *new_head, const char *msg)
371 struct strbuf reflog_message = STRBUF_INIT;
372 const unsigned char *head = head_commit->object.sha1;
374 if (!msg)
375 strbuf_addstr(&reflog_message, getenv("GIT_REFLOG_ACTION"));
376 else {
377 if (verbosity >= 0)
378 printf("%s\n", msg);
379 strbuf_addf(&reflog_message, "%s: %s",
380 getenv("GIT_REFLOG_ACTION"), msg);
382 if (squash) {
383 squash_message(head_commit, remoteheads);
384 } else {
385 if (verbosity >= 0 && !merge_msg.len)
386 printf(_("No merge message -- not updating HEAD\n"));
387 else {
388 const char *argv_gc_auto[] = { "gc", "--auto", NULL };
389 update_ref(reflog_message.buf, "HEAD",
390 new_head, head, 0,
391 DIE_ON_ERR);
393 * We ignore errors in 'gc --auto', since the
394 * user should see them.
396 run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
399 if (new_head && show_diffstat) {
400 struct diff_options opts;
401 diff_setup(&opts);
402 opts.stat_width = -1; /* use full terminal width */
403 opts.stat_graph_width = -1; /* respect statGraphWidth config */
404 opts.output_format |=
405 DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
406 opts.detect_rename = DIFF_DETECT_RENAME;
407 if (diff_setup_done(&opts) < 0)
408 die(_("diff_setup_done failed"));
409 diff_tree_sha1(head, new_head, "", &opts);
410 diffcore_std(&opts);
411 diff_flush(&opts);
414 /* Run a post-merge hook */
415 run_hook(NULL, "post-merge", squash ? "1" : "0", NULL);
417 strbuf_release(&reflog_message);
420 /* Get the name for the merge commit's message. */
421 static void merge_name(const char *remote, struct strbuf *msg)
423 struct commit *remote_head;
424 unsigned char branch_head[20];
425 struct strbuf buf = STRBUF_INIT;
426 struct strbuf bname = STRBUF_INIT;
427 const char *ptr;
428 char *found_ref;
429 int len, early;
431 strbuf_branchname(&bname, remote);
432 remote = bname.buf;
434 memset(branch_head, 0, sizeof(branch_head));
435 remote_head = get_merge_parent(remote);
436 if (!remote_head)
437 die(_("'%s' does not point to a commit"), remote);
439 if (dwim_ref(remote, strlen(remote), branch_head, &found_ref) > 0) {
440 if (!prefixcmp(found_ref, "refs/heads/")) {
441 strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
442 sha1_to_hex(branch_head), remote);
443 goto cleanup;
445 if (!prefixcmp(found_ref, "refs/tags/")) {
446 strbuf_addf(msg, "%s\t\ttag '%s' of .\n",
447 sha1_to_hex(branch_head), remote);
448 goto cleanup;
450 if (!prefixcmp(found_ref, "refs/remotes/")) {
451 strbuf_addf(msg, "%s\t\tremote-tracking branch '%s' of .\n",
452 sha1_to_hex(branch_head), remote);
453 goto cleanup;
457 /* See if remote matches <name>^^^.. or <name>~<number> */
458 for (len = 0, ptr = remote + strlen(remote);
459 remote < ptr && ptr[-1] == '^';
460 ptr--)
461 len++;
462 if (len)
463 early = 1;
464 else {
465 early = 0;
466 ptr = strrchr(remote, '~');
467 if (ptr) {
468 int seen_nonzero = 0;
470 len++; /* count ~ */
471 while (*++ptr && isdigit(*ptr)) {
472 seen_nonzero |= (*ptr != '0');
473 len++;
475 if (*ptr)
476 len = 0; /* not ...~<number> */
477 else if (seen_nonzero)
478 early = 1;
479 else if (len == 1)
480 early = 1; /* "name~" is "name~1"! */
483 if (len) {
484 struct strbuf truname = STRBUF_INIT;
485 strbuf_addstr(&truname, "refs/heads/");
486 strbuf_addstr(&truname, remote);
487 strbuf_setlen(&truname, truname.len - len);
488 if (ref_exists(truname.buf)) {
489 strbuf_addf(msg,
490 "%s\t\tbranch '%s'%s of .\n",
491 sha1_to_hex(remote_head->object.sha1),
492 truname.buf + 11,
493 (early ? " (early part)" : ""));
494 strbuf_release(&truname);
495 goto cleanup;
499 if (!strcmp(remote, "FETCH_HEAD") &&
500 !access(git_path("FETCH_HEAD"), R_OK)) {
501 const char *filename;
502 FILE *fp;
503 struct strbuf line = STRBUF_INIT;
504 char *ptr;
506 filename = git_path("FETCH_HEAD");
507 fp = fopen(filename, "r");
508 if (!fp)
509 die_errno(_("could not open '%s' for reading"),
510 filename);
511 strbuf_getline(&line, fp, '\n');
512 fclose(fp);
513 ptr = strstr(line.buf, "\tnot-for-merge\t");
514 if (ptr)
515 strbuf_remove(&line, ptr-line.buf+1, 13);
516 strbuf_addbuf(msg, &line);
517 strbuf_release(&line);
518 goto cleanup;
520 strbuf_addf(msg, "%s\t\tcommit '%s'\n",
521 sha1_to_hex(remote_head->object.sha1), remote);
522 cleanup:
523 strbuf_release(&buf);
524 strbuf_release(&bname);
527 static void parse_branch_merge_options(char *bmo)
529 const char **argv;
530 int argc;
532 if (!bmo)
533 return;
534 argc = split_cmdline(bmo, &argv);
535 if (argc < 0)
536 die(_("Bad branch.%s.mergeoptions string: %s"), branch,
537 split_cmdline_strerror(argc));
538 argv = xrealloc(argv, sizeof(*argv) * (argc + 2));
539 memmove(argv + 1, argv, sizeof(*argv) * (argc + 1));
540 argc++;
541 argv[0] = "branch.*.mergeoptions";
542 parse_options(argc, argv, NULL, builtin_merge_options,
543 builtin_merge_usage, 0);
544 free(argv);
547 static int git_merge_config(const char *k, const char *v, void *cb)
549 int status;
551 if (branch && !prefixcmp(k, "branch.") &&
552 !prefixcmp(k + 7, branch) &&
553 !strcmp(k + 7 + strlen(branch), ".mergeoptions")) {
554 free(branch_mergeoptions);
555 branch_mergeoptions = xstrdup(v);
556 return 0;
559 if (!strcmp(k, "merge.diffstat") || !strcmp(k, "merge.stat"))
560 show_diffstat = git_config_bool(k, v);
561 else if (!strcmp(k, "pull.twohead"))
562 return git_config_string(&pull_twohead, k, v);
563 else if (!strcmp(k, "pull.octopus"))
564 return git_config_string(&pull_octopus, k, v);
565 else if (!strcmp(k, "merge.renormalize"))
566 option_renormalize = git_config_bool(k, v);
567 else if (!strcmp(k, "merge.ff")) {
568 int boolval = git_config_maybe_bool(k, v);
569 if (0 <= boolval) {
570 allow_fast_forward = boolval;
571 } else if (v && !strcmp(v, "only")) {
572 allow_fast_forward = 1;
573 fast_forward_only = 1;
574 } /* do not barf on values from future versions of git */
575 return 0;
576 } else if (!strcmp(k, "merge.defaulttoupstream")) {
577 default_to_upstream = git_config_bool(k, v);
578 return 0;
581 status = fmt_merge_msg_config(k, v, cb);
582 if (status)
583 return status;
584 status = git_gpg_config(k, v, NULL);
585 if (status)
586 return status;
587 return git_diff_ui_config(k, v, cb);
590 static int read_tree_trivial(unsigned char *common, unsigned char *head,
591 unsigned char *one)
593 int i, nr_trees = 0;
594 struct tree *trees[MAX_UNPACK_TREES];
595 struct tree_desc t[MAX_UNPACK_TREES];
596 struct unpack_trees_options opts;
598 memset(&opts, 0, sizeof(opts));
599 opts.head_idx = 2;
600 opts.src_index = &the_index;
601 opts.dst_index = &the_index;
602 opts.update = 1;
603 opts.verbose_update = 1;
604 opts.trivial_merges_only = 1;
605 opts.merge = 1;
606 trees[nr_trees] = parse_tree_indirect(common);
607 if (!trees[nr_trees++])
608 return -1;
609 trees[nr_trees] = parse_tree_indirect(head);
610 if (!trees[nr_trees++])
611 return -1;
612 trees[nr_trees] = parse_tree_indirect(one);
613 if (!trees[nr_trees++])
614 return -1;
615 opts.fn = threeway_merge;
616 cache_tree_free(&active_cache_tree);
617 for (i = 0; i < nr_trees; i++) {
618 parse_tree(trees[i]);
619 init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
621 if (unpack_trees(nr_trees, t, &opts))
622 return -1;
623 return 0;
626 static void write_tree_trivial(unsigned char *sha1)
628 if (write_cache_as_tree(sha1, 0, NULL))
629 die(_("git write-tree failed to write a tree"));
632 static const char *merge_argument(struct commit *commit)
634 if (commit)
635 return sha1_to_hex(commit->object.sha1);
636 else
637 return EMPTY_TREE_SHA1_HEX;
640 int try_merge_command(const char *strategy, size_t xopts_nr,
641 const char **xopts, struct commit_list *common,
642 const char *head_arg, struct commit_list *remotes)
644 const char **args;
645 int i = 0, x = 0, ret;
646 struct commit_list *j;
647 struct strbuf buf = STRBUF_INIT;
649 args = xmalloc((4 + xopts_nr + commit_list_count(common) +
650 commit_list_count(remotes)) * sizeof(char *));
651 strbuf_addf(&buf, "merge-%s", strategy);
652 args[i++] = buf.buf;
653 for (x = 0; x < xopts_nr; x++) {
654 char *s = xmalloc(strlen(xopts[x])+2+1);
655 strcpy(s, "--");
656 strcpy(s+2, xopts[x]);
657 args[i++] = s;
659 for (j = common; j; j = j->next)
660 args[i++] = xstrdup(merge_argument(j->item));
661 args[i++] = "--";
662 args[i++] = head_arg;
663 for (j = remotes; j; j = j->next)
664 args[i++] = xstrdup(merge_argument(j->item));
665 args[i] = NULL;
666 ret = run_command_v_opt(args, RUN_GIT_CMD);
667 strbuf_release(&buf);
668 i = 1;
669 for (x = 0; x < xopts_nr; x++)
670 free((void *)args[i++]);
671 for (j = common; j; j = j->next)
672 free((void *)args[i++]);
673 i += 2;
674 for (j = remotes; j; j = j->next)
675 free((void *)args[i++]);
676 free(args);
677 discard_cache();
678 if (read_cache() < 0)
679 die(_("failed to read the cache"));
680 resolve_undo_clear();
682 return ret;
685 static int try_merge_strategy(const char *strategy, struct commit_list *common,
686 struct commit_list *remoteheads,
687 struct commit *head, const char *head_arg)
689 int index_fd;
690 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
692 index_fd = hold_locked_index(lock, 1);
693 refresh_cache(REFRESH_QUIET);
694 if (active_cache_changed &&
695 (write_cache(index_fd, active_cache, active_nr) ||
696 commit_locked_index(lock)))
697 return error(_("Unable to write index."));
698 rollback_lock_file(lock);
700 if (!strcmp(strategy, "recursive") || !strcmp(strategy, "subtree")) {
701 int clean, x;
702 struct commit *result;
703 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
704 int index_fd;
705 struct commit_list *reversed = NULL;
706 struct merge_options o;
707 struct commit_list *j;
709 if (remoteheads->next) {
710 error(_("Not handling anything other than two heads merge."));
711 return 2;
714 init_merge_options(&o);
715 if (!strcmp(strategy, "subtree"))
716 o.subtree_shift = "";
718 o.renormalize = option_renormalize;
719 o.show_rename_progress =
720 show_progress == -1 ? isatty(2) : show_progress;
722 for (x = 0; x < xopts_nr; x++)
723 if (parse_merge_opt(&o, xopts[x]))
724 die(_("Unknown option for merge-recursive: -X%s"), xopts[x]);
726 o.branch1 = head_arg;
727 o.branch2 = merge_remote_util(remoteheads->item)->name;
729 for (j = common; j; j = j->next)
730 commit_list_insert(j->item, &reversed);
732 index_fd = hold_locked_index(lock, 1);
733 clean = merge_recursive(&o, head,
734 remoteheads->item, reversed, &result);
735 if (active_cache_changed &&
736 (write_cache(index_fd, active_cache, active_nr) ||
737 commit_locked_index(lock)))
738 die (_("unable to write %s"), get_index_file());
739 rollback_lock_file(lock);
740 return clean ? 0 : 1;
741 } else {
742 return try_merge_command(strategy, xopts_nr, xopts,
743 common, head_arg, remoteheads);
747 static void count_diff_files(struct diff_queue_struct *q,
748 struct diff_options *opt, void *data)
750 int *count = data;
752 (*count) += q->nr;
755 static int count_unmerged_entries(void)
757 int i, ret = 0;
759 for (i = 0; i < active_nr; i++)
760 if (ce_stage(active_cache[i]))
761 ret++;
763 return ret;
766 int checkout_fast_forward(const unsigned char *head, const unsigned char *remote)
768 struct tree *trees[MAX_UNPACK_TREES];
769 struct unpack_trees_options opts;
770 struct tree_desc t[MAX_UNPACK_TREES];
771 int i, fd, nr_trees = 0;
772 struct dir_struct dir;
773 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
775 refresh_cache(REFRESH_QUIET);
777 fd = hold_locked_index(lock_file, 1);
779 memset(&trees, 0, sizeof(trees));
780 memset(&opts, 0, sizeof(opts));
781 memset(&t, 0, sizeof(t));
782 if (overwrite_ignore) {
783 memset(&dir, 0, sizeof(dir));
784 dir.flags |= DIR_SHOW_IGNORED;
785 setup_standard_excludes(&dir);
786 opts.dir = &dir;
789 opts.head_idx = 1;
790 opts.src_index = &the_index;
791 opts.dst_index = &the_index;
792 opts.update = 1;
793 opts.verbose_update = 1;
794 opts.merge = 1;
795 opts.fn = twoway_merge;
796 setup_unpack_trees_porcelain(&opts, "merge");
798 trees[nr_trees] = parse_tree_indirect(head);
799 if (!trees[nr_trees++])
800 return -1;
801 trees[nr_trees] = parse_tree_indirect(remote);
802 if (!trees[nr_trees++])
803 return -1;
804 for (i = 0; i < nr_trees; i++) {
805 parse_tree(trees[i]);
806 init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
808 if (unpack_trees(nr_trees, t, &opts))
809 return -1;
810 if (write_cache(fd, active_cache, active_nr) ||
811 commit_locked_index(lock_file))
812 die(_("unable to write new index file"));
813 return 0;
816 static void split_merge_strategies(const char *string, struct strategy **list,
817 int *nr, int *alloc)
819 char *p, *q, *buf;
821 if (!string)
822 return;
824 buf = xstrdup(string);
825 q = buf;
826 for (;;) {
827 p = strchr(q, ' ');
828 if (!p) {
829 ALLOC_GROW(*list, *nr + 1, *alloc);
830 (*list)[(*nr)++].name = xstrdup(q);
831 free(buf);
832 return;
833 } else {
834 *p = '\0';
835 ALLOC_GROW(*list, *nr + 1, *alloc);
836 (*list)[(*nr)++].name = xstrdup(q);
837 q = ++p;
842 static void add_strategies(const char *string, unsigned attr)
844 struct strategy *list = NULL;
845 int list_alloc = 0, list_nr = 0, i;
847 memset(&list, 0, sizeof(list));
848 split_merge_strategies(string, &list, &list_nr, &list_alloc);
849 if (list) {
850 for (i = 0; i < list_nr; i++)
851 append_strategy(get_strategy(list[i].name));
852 return;
854 for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
855 if (all_strategy[i].attr & attr)
856 append_strategy(&all_strategy[i]);
860 static void write_merge_msg(struct strbuf *msg)
862 const char *filename = git_path("MERGE_MSG");
863 int fd = open(filename, O_WRONLY | O_CREAT, 0666);
864 if (fd < 0)
865 die_errno(_("Could not open '%s' for writing"),
866 filename);
867 if (write_in_full(fd, msg->buf, msg->len) != msg->len)
868 die_errno(_("Could not write to '%s'"), filename);
869 close(fd);
872 static void read_merge_msg(struct strbuf *msg)
874 const char *filename = git_path("MERGE_MSG");
875 strbuf_reset(msg);
876 if (strbuf_read_file(msg, filename, 0) < 0)
877 die_errno(_("Could not read from '%s'"), filename);
880 static void write_merge_state(struct commit_list *);
881 static void abort_commit(struct commit_list *remoteheads, const char *err_msg)
883 if (err_msg)
884 error("%s", err_msg);
885 fprintf(stderr,
886 _("Not committing merge; use 'git commit' to complete the merge.\n"));
887 write_merge_state(remoteheads);
888 exit(1);
891 static const char merge_editor_comment[] =
892 N_("Please enter a commit message to explain why this merge is necessary,\n"
893 "especially if it merges an updated upstream into a topic branch.\n"
894 "\n"
895 "Lines starting with '#' will be ignored, and an empty message aborts\n"
896 "the commit.\n");
898 static void prepare_to_commit(struct commit_list *remoteheads)
900 struct strbuf msg = STRBUF_INIT;
901 const char *comment = _(merge_editor_comment);
902 strbuf_addbuf(&msg, &merge_msg);
903 strbuf_addch(&msg, '\n');
904 if (0 < option_edit)
905 strbuf_add_lines(&msg, "# ", comment, strlen(comment));
906 write_merge_msg(&msg);
907 run_hook(get_index_file(), "prepare-commit-msg",
908 git_path("MERGE_MSG"), "merge", NULL, NULL);
909 if (0 < option_edit) {
910 if (launch_editor(git_path("MERGE_MSG"), NULL, NULL))
911 abort_commit(remoteheads, NULL);
913 read_merge_msg(&msg);
914 stripspace(&msg, 0 < option_edit);
915 if (!msg.len)
916 abort_commit(remoteheads, _("Empty commit message."));
917 strbuf_release(&merge_msg);
918 strbuf_addbuf(&merge_msg, &msg);
919 strbuf_release(&msg);
922 static int merge_trivial(struct commit *head, struct commit_list *remoteheads)
924 unsigned char result_tree[20], result_commit[20];
925 struct commit_list *parent = xmalloc(sizeof(*parent));
927 write_tree_trivial(result_tree);
928 printf(_("Wonderful.\n"));
929 parent->item = head;
930 parent->next = xmalloc(sizeof(*parent->next));
931 parent->next->item = remoteheads->item;
932 parent->next->next = NULL;
933 prepare_to_commit(remoteheads);
934 if (commit_tree(&merge_msg, result_tree, parent, result_commit, NULL,
935 sign_commit))
936 die(_("failed to write commit object"));
937 finish(head, remoteheads, result_commit, "In-index merge");
938 drop_save();
939 return 0;
942 static int finish_automerge(struct commit *head,
943 int head_subsumed,
944 struct commit_list *common,
945 struct commit_list *remoteheads,
946 unsigned char *result_tree,
947 const char *wt_strategy)
949 struct commit_list *parents = NULL;
950 struct strbuf buf = STRBUF_INIT;
951 unsigned char result_commit[20];
953 free_commit_list(common);
954 parents = remoteheads;
955 if (!head_subsumed || !allow_fast_forward)
956 commit_list_insert(head, &parents);
957 strbuf_addch(&merge_msg, '\n');
958 prepare_to_commit(remoteheads);
959 if (commit_tree(&merge_msg, result_tree, parents, result_commit,
960 NULL, sign_commit))
961 die(_("failed to write commit object"));
962 strbuf_addf(&buf, "Merge made by the '%s' strategy.", wt_strategy);
963 finish(head, remoteheads, result_commit, buf.buf);
964 strbuf_release(&buf);
965 drop_save();
966 return 0;
969 static int suggest_conflicts(int renormalizing)
971 const char *filename;
972 FILE *fp;
973 int pos;
975 filename = git_path("MERGE_MSG");
976 fp = fopen(filename, "a");
977 if (!fp)
978 die_errno(_("Could not open '%s' for writing"), filename);
979 fprintf(fp, "\nConflicts:\n");
980 for (pos = 0; pos < active_nr; pos++) {
981 struct cache_entry *ce = active_cache[pos];
983 if (ce_stage(ce)) {
984 fprintf(fp, "\t%s\n", ce->name);
985 while (pos + 1 < active_nr &&
986 !strcmp(ce->name,
987 active_cache[pos + 1]->name))
988 pos++;
991 fclose(fp);
992 rerere(allow_rerere_auto);
993 printf(_("Automatic merge failed; "
994 "fix conflicts and then commit the result.\n"));
995 return 1;
998 static struct commit *is_old_style_invocation(int argc, const char **argv,
999 const unsigned char *head)
1001 struct commit *second_token = NULL;
1002 if (argc > 2) {
1003 unsigned char second_sha1[20];
1005 if (get_sha1(argv[1], second_sha1))
1006 return NULL;
1007 second_token = lookup_commit_reference_gently(second_sha1, 0);
1008 if (!second_token)
1009 die(_("'%s' is not a commit"), argv[1]);
1010 if (hashcmp(second_token->object.sha1, head))
1011 return NULL;
1013 return second_token;
1016 static int evaluate_result(void)
1018 int cnt = 0;
1019 struct rev_info rev;
1021 /* Check how many files differ. */
1022 init_revisions(&rev, "");
1023 setup_revisions(0, NULL, &rev, NULL);
1024 rev.diffopt.output_format |=
1025 DIFF_FORMAT_CALLBACK;
1026 rev.diffopt.format_callback = count_diff_files;
1027 rev.diffopt.format_callback_data = &cnt;
1028 run_diff_files(&rev, 0);
1031 * Check how many unmerged entries are
1032 * there.
1034 cnt += count_unmerged_entries();
1036 return cnt;
1040 * Pretend as if the user told us to merge with the tracking
1041 * branch we have for the upstream of the current branch
1043 static int setup_with_upstream(const char ***argv)
1045 struct branch *branch = branch_get(NULL);
1046 int i;
1047 const char **args;
1049 if (!branch)
1050 die(_("No current branch."));
1051 if (!branch->remote)
1052 die(_("No remote for the current branch."));
1053 if (!branch->merge_nr)
1054 die(_("No default upstream defined for the current branch."));
1056 args = xcalloc(branch->merge_nr + 1, sizeof(char *));
1057 for (i = 0; i < branch->merge_nr; i++) {
1058 if (!branch->merge[i]->dst)
1059 die(_("No remote tracking branch for %s from %s"),
1060 branch->merge[i]->src, branch->remote_name);
1061 args[i] = branch->merge[i]->dst;
1063 args[i] = NULL;
1064 *argv = args;
1065 return i;
1068 static void write_merge_state(struct commit_list *remoteheads)
1070 const char *filename;
1071 int fd;
1072 struct commit_list *j;
1073 struct strbuf buf = STRBUF_INIT;
1075 for (j = remoteheads; j; j = j->next) {
1076 unsigned const char *sha1;
1077 struct commit *c = j->item;
1078 if (c->util && merge_remote_util(c)->obj) {
1079 sha1 = merge_remote_util(c)->obj->sha1;
1080 } else {
1081 sha1 = c->object.sha1;
1083 strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
1085 filename = git_path("MERGE_HEAD");
1086 fd = open(filename, O_WRONLY | O_CREAT, 0666);
1087 if (fd < 0)
1088 die_errno(_("Could not open '%s' for writing"), filename);
1089 if (write_in_full(fd, buf.buf, buf.len) != buf.len)
1090 die_errno(_("Could not write to '%s'"), filename);
1091 close(fd);
1092 strbuf_addch(&merge_msg, '\n');
1093 write_merge_msg(&merge_msg);
1095 filename = git_path("MERGE_MODE");
1096 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
1097 if (fd < 0)
1098 die_errno(_("Could not open '%s' for writing"), filename);
1099 strbuf_reset(&buf);
1100 if (!allow_fast_forward)
1101 strbuf_addf(&buf, "no-ff");
1102 if (write_in_full(fd, buf.buf, buf.len) != buf.len)
1103 die_errno(_("Could not write to '%s'"), filename);
1104 close(fd);
1107 static int default_edit_option(void)
1109 static const char name[] = "GIT_MERGE_AUTOEDIT";
1110 const char *e = getenv(name);
1111 struct stat st_stdin, st_stdout;
1113 if (have_message)
1114 /* an explicit -m msg without --[no-]edit */
1115 return 0;
1117 if (e) {
1118 int v = git_config_maybe_bool(name, e);
1119 if (v < 0)
1120 die("Bad value '%s' in environment '%s'", e, name);
1121 return v;
1124 /* Use editor if stdin and stdout are the same and is a tty */
1125 return (!fstat(0, &st_stdin) &&
1126 !fstat(1, &st_stdout) &&
1127 isatty(0) && isatty(1) &&
1128 st_stdin.st_dev == st_stdout.st_dev &&
1129 st_stdin.st_ino == st_stdout.st_ino &&
1130 st_stdin.st_mode == st_stdout.st_mode);
1133 static struct commit_list *collect_parents(struct commit *head_commit,
1134 int *head_subsumed,
1135 int argc, const char **argv)
1137 int i;
1138 struct commit_list *remoteheads = NULL, *parents, *next;
1139 struct commit_list **remotes = &remoteheads;
1141 if (head_commit)
1142 remotes = &commit_list_insert(head_commit, remotes)->next;
1143 for (i = 0; i < argc; i++) {
1144 struct commit *commit = get_merge_parent(argv[i]);
1145 if (!commit)
1146 die(_("%s - not something we can merge"), argv[i]);
1147 remotes = &commit_list_insert(commit, remotes)->next;
1149 *remotes = NULL;
1151 parents = reduce_heads(remoteheads);
1153 *head_subsumed = 1; /* we will flip this to 0 when we find it */
1154 for (remoteheads = NULL, remotes = &remoteheads;
1155 parents;
1156 parents = next) {
1157 struct commit *commit = parents->item;
1158 next = parents->next;
1159 if (commit == head_commit)
1160 *head_subsumed = 0;
1161 else
1162 remotes = &commit_list_insert(commit, remotes)->next;
1164 return remoteheads;
1167 int cmd_merge(int argc, const char **argv, const char *prefix)
1169 unsigned char result_tree[20];
1170 unsigned char stash[20];
1171 unsigned char head_sha1[20];
1172 struct commit *head_commit;
1173 struct strbuf buf = STRBUF_INIT;
1174 const char *head_arg;
1175 int flag, i, ret = 0, head_subsumed;
1176 int best_cnt = -1, merge_was_ok = 0, automerge_was_ok = 0;
1177 struct commit_list *common = NULL;
1178 const char *best_strategy = NULL, *wt_strategy = NULL;
1179 struct commit_list *remoteheads, *p;
1180 void *branch_to_free;
1182 if (argc == 2 && !strcmp(argv[1], "-h"))
1183 usage_with_options(builtin_merge_usage, builtin_merge_options);
1186 * Check if we are _not_ on a detached HEAD, i.e. if there is a
1187 * current branch.
1189 branch = branch_to_free = resolve_refdup("HEAD", head_sha1, 0, &flag);
1190 if (branch && !prefixcmp(branch, "refs/heads/"))
1191 branch += 11;
1192 if (!branch || is_null_sha1(head_sha1))
1193 head_commit = NULL;
1194 else
1195 head_commit = lookup_commit_or_die(head_sha1, "HEAD");
1197 git_config(git_merge_config, NULL);
1199 if (branch_mergeoptions)
1200 parse_branch_merge_options(branch_mergeoptions);
1201 argc = parse_options(argc, argv, prefix, builtin_merge_options,
1202 builtin_merge_usage, 0);
1203 if (shortlog_len < 0)
1204 shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
1206 if (verbosity < 0 && show_progress == -1)
1207 show_progress = 0;
1209 if (abort_current_merge) {
1210 int nargc = 2;
1211 const char *nargv[] = {"reset", "--merge", NULL};
1213 if (!file_exists(git_path("MERGE_HEAD")))
1214 die(_("There is no merge to abort (MERGE_HEAD missing)."));
1216 /* Invoke 'git reset --merge' */
1217 ret = cmd_reset(nargc, nargv, prefix);
1218 goto done;
1221 if (read_cache_unmerged())
1222 die_resolve_conflict("merge");
1224 if (file_exists(git_path("MERGE_HEAD"))) {
1226 * There is no unmerged entry, don't advise 'git
1227 * add/rm <file>', just 'git commit'.
1229 if (advice_resolve_conflict)
1230 die(_("You have not concluded your merge (MERGE_HEAD exists).\n"
1231 "Please, commit your changes before you can merge."));
1232 else
1233 die(_("You have not concluded your merge (MERGE_HEAD exists)."));
1235 if (file_exists(git_path("CHERRY_PICK_HEAD"))) {
1236 if (advice_resolve_conflict)
1237 die(_("You have not concluded your cherry-pick (CHERRY_PICK_HEAD exists).\n"
1238 "Please, commit your changes before you can merge."));
1239 else
1240 die(_("You have not concluded your cherry-pick (CHERRY_PICK_HEAD exists)."));
1242 resolve_undo_clear();
1244 if (verbosity < 0)
1245 show_diffstat = 0;
1247 if (squash) {
1248 if (!allow_fast_forward)
1249 die(_("You cannot combine --squash with --no-ff."));
1250 option_commit = 0;
1253 if (!allow_fast_forward && fast_forward_only)
1254 die(_("You cannot combine --no-ff with --ff-only."));
1256 if (!abort_current_merge) {
1257 if (!argc) {
1258 if (default_to_upstream)
1259 argc = setup_with_upstream(&argv);
1260 else
1261 die(_("No commit specified and merge.defaultToUpstream not set."));
1262 } else if (argc == 1 && !strcmp(argv[0], "-"))
1263 argv[0] = "@{-1}";
1265 if (!argc)
1266 usage_with_options(builtin_merge_usage,
1267 builtin_merge_options);
1270 * This could be traditional "merge <msg> HEAD <commit>..." and
1271 * the way we can tell it is to see if the second token is HEAD,
1272 * but some people might have misused the interface and used a
1273 * committish that is the same as HEAD there instead.
1274 * Traditional format never would have "-m" so it is an
1275 * additional safety measure to check for it.
1278 if (!have_message && head_commit &&
1279 is_old_style_invocation(argc, argv, head_commit->object.sha1)) {
1280 strbuf_addstr(&merge_msg, argv[0]);
1281 head_arg = argv[1];
1282 argv += 2;
1283 argc -= 2;
1284 remoteheads = collect_parents(head_commit, &head_subsumed, argc, argv);
1285 } else if (!head_commit) {
1286 struct commit *remote_head;
1288 * If the merged head is a valid one there is no reason
1289 * to forbid "git merge" into a branch yet to be born.
1290 * We do the same for "git pull".
1292 if (argc != 1)
1293 die(_("Can merge only exactly one commit into "
1294 "empty head"));
1295 if (squash)
1296 die(_("Squash commit into empty head not supported yet"));
1297 if (!allow_fast_forward)
1298 die(_("Non-fast-forward commit does not make sense into "
1299 "an empty head"));
1300 remoteheads = collect_parents(head_commit, &head_subsumed, argc, argv);
1301 remote_head = remoteheads->item;
1302 if (!remote_head)
1303 die(_("%s - not something we can merge"), argv[0]);
1304 read_empty(remote_head->object.sha1, 0);
1305 update_ref("initial pull", "HEAD", remote_head->object.sha1,
1306 NULL, 0, DIE_ON_ERR);
1307 goto done;
1308 } else {
1309 struct strbuf merge_names = STRBUF_INIT;
1311 /* We are invoked directly as the first-class UI. */
1312 head_arg = "HEAD";
1315 * All the rest are the commits being merged; prepare
1316 * the standard merge summary message to be appended
1317 * to the given message.
1319 remoteheads = collect_parents(head_commit, &head_subsumed, argc, argv);
1320 for (p = remoteheads; p; p = p->next)
1321 merge_name(merge_remote_util(p->item)->name, &merge_names);
1323 if (!have_message || shortlog_len) {
1324 struct fmt_merge_msg_opts opts;
1325 memset(&opts, 0, sizeof(opts));
1326 opts.add_title = !have_message;
1327 opts.shortlog_len = shortlog_len;
1329 fmt_merge_msg(&merge_names, &merge_msg, &opts);
1330 if (merge_msg.len)
1331 strbuf_setlen(&merge_msg, merge_msg.len - 1);
1335 if (!head_commit || !argc)
1336 usage_with_options(builtin_merge_usage,
1337 builtin_merge_options);
1339 strbuf_addstr(&buf, "merge");
1340 for (p = remoteheads; p; p = p->next)
1341 strbuf_addf(&buf, " %s", merge_remote_util(p->item)->name);
1342 setenv("GIT_REFLOG_ACTION", buf.buf, 0);
1343 strbuf_reset(&buf);
1345 for (p = remoteheads; p; p = p->next) {
1346 struct commit *commit = p->item;
1347 strbuf_addf(&buf, "GITHEAD_%s",
1348 sha1_to_hex(commit->object.sha1));
1349 setenv(buf.buf, merge_remote_util(commit)->name, 1);
1350 strbuf_reset(&buf);
1351 if (!fast_forward_only &&
1352 merge_remote_util(commit) &&
1353 merge_remote_util(commit)->obj &&
1354 merge_remote_util(commit)->obj->type == OBJ_TAG)
1355 allow_fast_forward = 0;
1358 if (option_edit < 0)
1359 option_edit = default_edit_option();
1361 if (!use_strategies) {
1362 if (!remoteheads)
1363 ; /* already up-to-date */
1364 else if (!remoteheads->next)
1365 add_strategies(pull_twohead, DEFAULT_TWOHEAD);
1366 else
1367 add_strategies(pull_octopus, DEFAULT_OCTOPUS);
1370 for (i = 0; i < use_strategies_nr; i++) {
1371 if (use_strategies[i]->attr & NO_FAST_FORWARD)
1372 allow_fast_forward = 0;
1373 if (use_strategies[i]->attr & NO_TRIVIAL)
1374 allow_trivial = 0;
1377 if (!remoteheads)
1378 ; /* already up-to-date */
1379 else if (!remoteheads->next)
1380 common = get_merge_bases(head_commit, remoteheads->item, 1);
1381 else {
1382 struct commit_list *list = remoteheads;
1383 commit_list_insert(head_commit, &list);
1384 common = get_octopus_merge_bases(list);
1385 free(list);
1388 update_ref("updating ORIG_HEAD", "ORIG_HEAD", head_commit->object.sha1,
1389 NULL, 0, DIE_ON_ERR);
1391 if (remoteheads && !common)
1392 ; /* No common ancestors found. We need a real merge. */
1393 else if (!remoteheads ||
1394 (!remoteheads->next && !common->next &&
1395 common->item == remoteheads->item)) {
1397 * If head can reach all the merge then we are up to date.
1398 * but first the most common case of merging one remote.
1400 finish_up_to_date("Already up-to-date.");
1401 goto done;
1402 } else if (allow_fast_forward && !remoteheads->next &&
1403 !common->next &&
1404 !hashcmp(common->item->object.sha1, head_commit->object.sha1)) {
1405 /* Again the most common case of merging one remote. */
1406 struct strbuf msg = STRBUF_INIT;
1407 struct commit *commit;
1408 char hex[41];
1410 strcpy(hex, find_unique_abbrev(head_commit->object.sha1, DEFAULT_ABBREV));
1412 if (verbosity >= 0)
1413 printf(_("Updating %s..%s\n"),
1414 hex,
1415 find_unique_abbrev(remoteheads->item->object.sha1,
1416 DEFAULT_ABBREV));
1417 strbuf_addstr(&msg, "Fast-forward");
1418 if (have_message)
1419 strbuf_addstr(&msg,
1420 " (no commit created; -m option ignored)");
1421 commit = remoteheads->item;
1422 if (!commit) {
1423 ret = 1;
1424 goto done;
1427 if (checkout_fast_forward(head_commit->object.sha1,
1428 commit->object.sha1)) {
1429 ret = 1;
1430 goto done;
1433 finish(head_commit, remoteheads, commit->object.sha1, msg.buf);
1434 drop_save();
1435 goto done;
1436 } else if (!remoteheads->next && common->next)
1439 * We are not doing octopus and not fast-forward. Need
1440 * a real merge.
1442 else if (!remoteheads->next && !common->next && option_commit) {
1444 * We are not doing octopus, not fast-forward, and have
1445 * only one common.
1447 refresh_cache(REFRESH_QUIET);
1448 if (allow_trivial && !fast_forward_only) {
1449 /* See if it is really trivial. */
1450 git_committer_info(IDENT_STRICT);
1451 printf(_("Trying really trivial in-index merge...\n"));
1452 if (!read_tree_trivial(common->item->object.sha1,
1453 head_commit->object.sha1,
1454 remoteheads->item->object.sha1)) {
1455 ret = merge_trivial(head_commit, remoteheads);
1456 goto done;
1458 printf(_("Nope.\n"));
1460 } else {
1462 * An octopus. If we can reach all the remote we are up
1463 * to date.
1465 int up_to_date = 1;
1466 struct commit_list *j;
1468 for (j = remoteheads; j; j = j->next) {
1469 struct commit_list *common_one;
1472 * Here we *have* to calculate the individual
1473 * merge_bases again, otherwise "git merge HEAD^
1474 * HEAD^^" would be missed.
1476 common_one = get_merge_bases(head_commit, j->item, 1);
1477 if (hashcmp(common_one->item->object.sha1,
1478 j->item->object.sha1)) {
1479 up_to_date = 0;
1480 break;
1483 if (up_to_date) {
1484 finish_up_to_date("Already up-to-date. Yeeah!");
1485 goto done;
1489 if (fast_forward_only)
1490 die(_("Not possible to fast-forward, aborting."));
1492 /* We are going to make a new commit. */
1493 git_committer_info(IDENT_STRICT);
1496 * At this point, we need a real merge. No matter what strategy
1497 * we use, it would operate on the index, possibly affecting the
1498 * working tree, and when resolved cleanly, have the desired
1499 * tree in the index -- this means that the index must be in
1500 * sync with the head commit. The strategies are responsible
1501 * to ensure this.
1503 if (use_strategies_nr == 1 ||
1505 * Stash away the local changes so that we can try more than one.
1507 save_state(stash))
1508 hashcpy(stash, null_sha1);
1510 for (i = 0; i < use_strategies_nr; i++) {
1511 int ret;
1512 if (i) {
1513 printf(_("Rewinding the tree to pristine...\n"));
1514 restore_state(head_commit->object.sha1, stash);
1516 if (use_strategies_nr != 1)
1517 printf(_("Trying merge strategy %s...\n"),
1518 use_strategies[i]->name);
1520 * Remember which strategy left the state in the working
1521 * tree.
1523 wt_strategy = use_strategies[i]->name;
1525 ret = try_merge_strategy(use_strategies[i]->name,
1526 common, remoteheads,
1527 head_commit, head_arg);
1528 if (!option_commit && !ret) {
1529 merge_was_ok = 1;
1531 * This is necessary here just to avoid writing
1532 * the tree, but later we will *not* exit with
1533 * status code 1 because merge_was_ok is set.
1535 ret = 1;
1538 if (ret) {
1540 * The backend exits with 1 when conflicts are
1541 * left to be resolved, with 2 when it does not
1542 * handle the given merge at all.
1544 if (ret == 1) {
1545 int cnt = evaluate_result();
1547 if (best_cnt <= 0 || cnt <= best_cnt) {
1548 best_strategy = use_strategies[i]->name;
1549 best_cnt = cnt;
1552 if (merge_was_ok)
1553 break;
1554 else
1555 continue;
1558 /* Automerge succeeded. */
1559 write_tree_trivial(result_tree);
1560 automerge_was_ok = 1;
1561 break;
1565 * If we have a resulting tree, that means the strategy module
1566 * auto resolved the merge cleanly.
1568 if (automerge_was_ok) {
1569 ret = finish_automerge(head_commit, head_subsumed,
1570 common, remoteheads,
1571 result_tree, wt_strategy);
1572 goto done;
1576 * Pick the result from the best strategy and have the user fix
1577 * it up.
1579 if (!best_strategy) {
1580 restore_state(head_commit->object.sha1, stash);
1581 if (use_strategies_nr > 1)
1582 fprintf(stderr,
1583 _("No merge strategy handled the merge.\n"));
1584 else
1585 fprintf(stderr, _("Merge with strategy %s failed.\n"),
1586 use_strategies[0]->name);
1587 ret = 2;
1588 goto done;
1589 } else if (best_strategy == wt_strategy)
1590 ; /* We already have its result in the working tree. */
1591 else {
1592 printf(_("Rewinding the tree to pristine...\n"));
1593 restore_state(head_commit->object.sha1, stash);
1594 printf(_("Using the %s to prepare resolving by hand.\n"),
1595 best_strategy);
1596 try_merge_strategy(best_strategy, common, remoteheads,
1597 head_commit, head_arg);
1600 if (squash)
1601 finish(head_commit, remoteheads, NULL, NULL);
1602 else
1603 write_merge_state(remoteheads);
1605 if (merge_was_ok)
1606 fprintf(stderr, _("Automatic merge went well; "
1607 "stopped before committing as requested\n"));
1608 else
1609 ret = suggest_conflicts(option_renormalize);
1611 done:
1612 free(branch_to_free);
1613 return ret;