parse_object: try internal cache before reading object db
[alt-git.git] / builtin / merge.c
blob4b0ca6550c130dc8efbf248c56503018b8bcb604
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"
31 #define DEFAULT_TWOHEAD (1<<0)
32 #define DEFAULT_OCTOPUS (1<<1)
33 #define NO_FAST_FORWARD (1<<2)
34 #define NO_TRIVIAL (1<<3)
36 struct strategy {
37 const char *name;
38 unsigned attr;
41 static const char * const builtin_merge_usage[] = {
42 "git merge [options] [<commit>...]",
43 "git merge [options] <msg> HEAD <commit>",
44 "git merge --abort",
45 NULL
48 static int show_diffstat = 1, shortlog_len = -1, squash;
49 static int option_commit = 1, allow_fast_forward = 1;
50 static int fast_forward_only, option_edit;
51 static int allow_trivial = 1, have_message;
52 static int overwrite_ignore = 1;
53 static struct strbuf merge_msg = STRBUF_INIT;
54 static struct commit_list *remoteheads;
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;
68 static struct strategy all_strategy[] = {
69 { "recursive", DEFAULT_TWOHEAD | NO_TRIVIAL },
70 { "octopus", DEFAULT_OCTOPUS },
71 { "resolve", 0 },
72 { "ours", NO_FAST_FORWARD | NO_TRIVIAL },
73 { "subtree", NO_FAST_FORWARD | NO_TRIVIAL },
76 static const char *pull_twohead, *pull_octopus;
78 static int option_parse_message(const struct option *opt,
79 const char *arg, int unset)
81 struct strbuf *buf = opt->value;
83 if (unset)
84 strbuf_setlen(buf, 0);
85 else if (arg) {
86 strbuf_addf(buf, "%s%s", buf->len ? "\n\n" : "", arg);
87 have_message = 1;
88 } else
89 return error(_("switch `m' requires a value"));
90 return 0;
93 static struct strategy *get_strategy(const char *name)
95 int i;
96 struct strategy *ret;
97 static struct cmdnames main_cmds, other_cmds;
98 static int loaded;
100 if (!name)
101 return NULL;
103 for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
104 if (!strcmp(name, all_strategy[i].name))
105 return &all_strategy[i];
107 if (!loaded) {
108 struct cmdnames not_strategies;
109 loaded = 1;
111 memset(&not_strategies, 0, sizeof(struct cmdnames));
112 load_command_list("git-merge-", &main_cmds, &other_cmds);
113 for (i = 0; i < main_cmds.cnt; i++) {
114 int j, found = 0;
115 struct cmdname *ent = main_cmds.names[i];
116 for (j = 0; j < ARRAY_SIZE(all_strategy); j++)
117 if (!strncmp(ent->name, all_strategy[j].name, ent->len)
118 && !all_strategy[j].name[ent->len])
119 found = 1;
120 if (!found)
121 add_cmdname(&not_strategies, ent->name, ent->len);
123 exclude_cmds(&main_cmds, &not_strategies);
125 if (!is_in_cmdlist(&main_cmds, name) && !is_in_cmdlist(&other_cmds, name)) {
126 fprintf(stderr, _("Could not find merge strategy '%s'.\n"), name);
127 fprintf(stderr, _("Available strategies are:"));
128 for (i = 0; i < main_cmds.cnt; i++)
129 fprintf(stderr, " %s", main_cmds.names[i]->name);
130 fprintf(stderr, ".\n");
131 if (other_cmds.cnt) {
132 fprintf(stderr, _("Available custom strategies are:"));
133 for (i = 0; i < other_cmds.cnt; i++)
134 fprintf(stderr, " %s", other_cmds.names[i]->name);
135 fprintf(stderr, ".\n");
137 exit(1);
140 ret = xcalloc(1, sizeof(struct strategy));
141 ret->name = xstrdup(name);
142 ret->attr = NO_TRIVIAL;
143 return ret;
146 static void append_strategy(struct strategy *s)
148 ALLOC_GROW(use_strategies, use_strategies_nr + 1, use_strategies_alloc);
149 use_strategies[use_strategies_nr++] = s;
152 static int option_parse_strategy(const struct option *opt,
153 const char *name, int unset)
155 if (unset)
156 return 0;
158 append_strategy(get_strategy(name));
159 return 0;
162 static int option_parse_x(const struct option *opt,
163 const char *arg, int unset)
165 if (unset)
166 return 0;
168 ALLOC_GROW(xopts, xopts_nr + 1, xopts_alloc);
169 xopts[xopts_nr++] = xstrdup(arg);
170 return 0;
173 static int option_parse_n(const struct option *opt,
174 const char *arg, int unset)
176 show_diffstat = unset;
177 return 0;
180 static struct option builtin_merge_options[] = {
181 { OPTION_CALLBACK, 'n', NULL, NULL, NULL,
182 "do not show a diffstat at the end of the merge",
183 PARSE_OPT_NOARG, option_parse_n },
184 OPT_BOOLEAN(0, "stat", &show_diffstat,
185 "show a diffstat at the end of the merge"),
186 OPT_BOOLEAN(0, "summary", &show_diffstat, "(synonym to --stat)"),
187 { OPTION_INTEGER, 0, "log", &shortlog_len, "n",
188 "add (at most <n>) entries from shortlog to merge commit message",
189 PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
190 OPT_BOOLEAN(0, "squash", &squash,
191 "create a single commit instead of doing a merge"),
192 OPT_BOOLEAN(0, "commit", &option_commit,
193 "perform a commit if the merge succeeds (default)"),
194 OPT_BOOLEAN('e', "edit", &option_edit,
195 "edit message before committing"),
196 OPT_BOOLEAN(0, "ff", &allow_fast_forward,
197 "allow fast-forward (default)"),
198 OPT_BOOLEAN(0, "ff-only", &fast_forward_only,
199 "abort if fast-forward is not possible"),
200 OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
201 OPT_CALLBACK('s', "strategy", &use_strategies, "strategy",
202 "merge strategy to use", option_parse_strategy),
203 OPT_CALLBACK('X', "strategy-option", &xopts, "option=value",
204 "option for selected merge strategy", option_parse_x),
205 OPT_CALLBACK('m', "message", &merge_msg, "message",
206 "merge commit message (for a non-fast-forward merge)",
207 option_parse_message),
208 OPT__VERBOSITY(&verbosity),
209 OPT_BOOLEAN(0, "abort", &abort_current_merge,
210 "abort the current in-progress merge"),
211 OPT_SET_INT(0, "progress", &show_progress, "force progress reporting", 1),
212 OPT_BOOLEAN(0, "overwrite-ignore", &overwrite_ignore, "update ignored files (default)"),
213 OPT_END()
216 /* Cleans up metadata that is uninteresting after a succeeded merge. */
217 static void drop_save(void)
219 unlink(git_path("MERGE_HEAD"));
220 unlink(git_path("MERGE_MSG"));
221 unlink(git_path("MERGE_MODE"));
224 static int save_state(unsigned char *stash)
226 int len;
227 struct child_process cp;
228 struct strbuf buffer = STRBUF_INIT;
229 const char *argv[] = {"stash", "create", NULL};
231 memset(&cp, 0, sizeof(cp));
232 cp.argv = argv;
233 cp.out = -1;
234 cp.git_cmd = 1;
236 if (start_command(&cp))
237 die(_("could not run stash."));
238 len = strbuf_read(&buffer, cp.out, 1024);
239 close(cp.out);
241 if (finish_command(&cp) || len < 0)
242 die(_("stash failed"));
243 else if (!len) /* no changes */
244 return -1;
245 strbuf_setlen(&buffer, buffer.len-1);
246 if (get_sha1(buffer.buf, stash))
247 die(_("not a valid object: %s"), buffer.buf);
248 return 0;
251 static void read_empty(unsigned const char *sha1, int verbose)
253 int i = 0;
254 const char *args[7];
256 args[i++] = "read-tree";
257 if (verbose)
258 args[i++] = "-v";
259 args[i++] = "-m";
260 args[i++] = "-u";
261 args[i++] = EMPTY_TREE_SHA1_HEX;
262 args[i++] = sha1_to_hex(sha1);
263 args[i] = NULL;
265 if (run_command_v_opt(args, RUN_GIT_CMD))
266 die(_("read-tree failed"));
269 static void reset_hard(unsigned const char *sha1, int verbose)
271 int i = 0;
272 const char *args[6];
274 args[i++] = "read-tree";
275 if (verbose)
276 args[i++] = "-v";
277 args[i++] = "--reset";
278 args[i++] = "-u";
279 args[i++] = sha1_to_hex(sha1);
280 args[i] = NULL;
282 if (run_command_v_opt(args, RUN_GIT_CMD))
283 die(_("read-tree failed"));
286 static void restore_state(const unsigned char *head,
287 const unsigned char *stash)
289 struct strbuf sb = STRBUF_INIT;
290 const char *args[] = { "stash", "apply", NULL, NULL };
292 if (is_null_sha1(stash))
293 return;
295 reset_hard(head, 1);
297 args[2] = sha1_to_hex(stash);
300 * It is OK to ignore error here, for example when there was
301 * nothing to restore.
303 run_command_v_opt(args, RUN_GIT_CMD);
305 strbuf_release(&sb);
306 refresh_cache(REFRESH_QUIET);
309 /* This is called when no merge was necessary. */
310 static void finish_up_to_date(const char *msg)
312 if (verbosity >= 0)
313 printf("%s%s\n", squash ? _(" (nothing to squash)") : "", msg);
314 drop_save();
317 static void squash_message(struct commit *commit)
319 struct rev_info rev;
320 struct strbuf out = STRBUF_INIT;
321 struct commit_list *j;
322 const char *filename;
323 int fd;
324 struct pretty_print_context ctx = {0};
326 printf(_("Squash commit -- not updating HEAD\n"));
327 filename = git_path("SQUASH_MSG");
328 fd = open(filename, O_WRONLY | O_CREAT, 0666);
329 if (fd < 0)
330 die_errno(_("Could not write to '%s'"), filename);
332 init_revisions(&rev, NULL);
333 rev.ignore_merges = 1;
334 rev.commit_format = CMIT_FMT_MEDIUM;
336 commit->object.flags |= UNINTERESTING;
337 add_pending_object(&rev, &commit->object, NULL);
339 for (j = remoteheads; j; j = j->next)
340 add_pending_object(&rev, &j->item->object, NULL);
342 setup_revisions(0, NULL, &rev, NULL);
343 if (prepare_revision_walk(&rev))
344 die(_("revision walk setup failed"));
346 ctx.abbrev = rev.abbrev;
347 ctx.date_mode = rev.date_mode;
348 ctx.fmt = rev.commit_format;
350 strbuf_addstr(&out, "Squashed commit of the following:\n");
351 while ((commit = get_revision(&rev)) != NULL) {
352 strbuf_addch(&out, '\n');
353 strbuf_addf(&out, "commit %s\n",
354 sha1_to_hex(commit->object.sha1));
355 pretty_print_commit(&ctx, commit, &out);
357 if (write(fd, out.buf, out.len) < 0)
358 die_errno(_("Writing SQUASH_MSG"));
359 if (close(fd))
360 die_errno(_("Finishing SQUASH_MSG"));
361 strbuf_release(&out);
364 static void finish(struct commit *head_commit,
365 const unsigned char *new_head, const char *msg)
367 struct strbuf reflog_message = STRBUF_INIT;
368 const unsigned char *head = head_commit->object.sha1;
370 if (!msg)
371 strbuf_addstr(&reflog_message, getenv("GIT_REFLOG_ACTION"));
372 else {
373 if (verbosity >= 0)
374 printf("%s\n", msg);
375 strbuf_addf(&reflog_message, "%s: %s",
376 getenv("GIT_REFLOG_ACTION"), msg);
378 if (squash) {
379 squash_message(head_commit);
380 } else {
381 if (verbosity >= 0 && !merge_msg.len)
382 printf(_("No merge message -- not updating HEAD\n"));
383 else {
384 const char *argv_gc_auto[] = { "gc", "--auto", NULL };
385 update_ref(reflog_message.buf, "HEAD",
386 new_head, head, 0,
387 DIE_ON_ERR);
389 * We ignore errors in 'gc --auto', since the
390 * user should see them.
392 run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
395 if (new_head && show_diffstat) {
396 struct diff_options opts;
397 diff_setup(&opts);
398 opts.output_format |=
399 DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
400 opts.detect_rename = DIFF_DETECT_RENAME;
401 if (diff_setup_done(&opts) < 0)
402 die(_("diff_setup_done failed"));
403 diff_tree_sha1(head, new_head, "", &opts);
404 diffcore_std(&opts);
405 diff_flush(&opts);
408 /* Run a post-merge hook */
409 run_hook(NULL, "post-merge", squash ? "1" : "0", NULL);
411 strbuf_release(&reflog_message);
414 /* Get the name for the merge commit's message. */
415 static void merge_name(const char *remote, struct strbuf *msg)
417 struct commit *remote_head;
418 unsigned char branch_head[20];
419 struct strbuf buf = STRBUF_INIT;
420 struct strbuf bname = STRBUF_INIT;
421 const char *ptr;
422 char *found_ref;
423 int len, early;
425 strbuf_branchname(&bname, remote);
426 remote = bname.buf;
428 memset(branch_head, 0, sizeof(branch_head));
429 remote_head = get_merge_parent(remote);
430 if (!remote_head)
431 die(_("'%s' does not point to a commit"), remote);
433 if (dwim_ref(remote, strlen(remote), branch_head, &found_ref) > 0) {
434 if (!prefixcmp(found_ref, "refs/heads/")) {
435 strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
436 sha1_to_hex(branch_head), remote);
437 goto cleanup;
439 if (!prefixcmp(found_ref, "refs/tags/")) {
440 strbuf_addf(msg, "%s\t\ttag '%s' of .\n",
441 sha1_to_hex(branch_head), remote);
442 goto cleanup;
444 if (!prefixcmp(found_ref, "refs/remotes/")) {
445 strbuf_addf(msg, "%s\t\tremote-tracking branch '%s' of .\n",
446 sha1_to_hex(branch_head), remote);
447 goto cleanup;
451 /* See if remote matches <name>^^^.. or <name>~<number> */
452 for (len = 0, ptr = remote + strlen(remote);
453 remote < ptr && ptr[-1] == '^';
454 ptr--)
455 len++;
456 if (len)
457 early = 1;
458 else {
459 early = 0;
460 ptr = strrchr(remote, '~');
461 if (ptr) {
462 int seen_nonzero = 0;
464 len++; /* count ~ */
465 while (*++ptr && isdigit(*ptr)) {
466 seen_nonzero |= (*ptr != '0');
467 len++;
469 if (*ptr)
470 len = 0; /* not ...~<number> */
471 else if (seen_nonzero)
472 early = 1;
473 else if (len == 1)
474 early = 1; /* "name~" is "name~1"! */
477 if (len) {
478 struct strbuf truname = STRBUF_INIT;
479 strbuf_addstr(&truname, "refs/heads/");
480 strbuf_addstr(&truname, remote);
481 strbuf_setlen(&truname, truname.len - len);
482 if (ref_exists(truname.buf)) {
483 strbuf_addf(msg,
484 "%s\t\tbranch '%s'%s of .\n",
485 sha1_to_hex(remote_head->object.sha1),
486 truname.buf + 11,
487 (early ? " (early part)" : ""));
488 strbuf_release(&truname);
489 goto cleanup;
493 if (!strcmp(remote, "FETCH_HEAD") &&
494 !access(git_path("FETCH_HEAD"), R_OK)) {
495 const char *filename;
496 FILE *fp;
497 struct strbuf line = STRBUF_INIT;
498 char *ptr;
500 filename = git_path("FETCH_HEAD");
501 fp = fopen(filename, "r");
502 if (!fp)
503 die_errno(_("could not open '%s' for reading"),
504 filename);
505 strbuf_getline(&line, fp, '\n');
506 fclose(fp);
507 ptr = strstr(line.buf, "\tnot-for-merge\t");
508 if (ptr)
509 strbuf_remove(&line, ptr-line.buf+1, 13);
510 strbuf_addbuf(msg, &line);
511 strbuf_release(&line);
512 goto cleanup;
514 strbuf_addf(msg, "%s\t\tcommit '%s'\n",
515 sha1_to_hex(remote_head->object.sha1), remote);
516 cleanup:
517 strbuf_release(&buf);
518 strbuf_release(&bname);
521 static void parse_branch_merge_options(char *bmo)
523 const char **argv;
524 int argc;
526 if (!bmo)
527 return;
528 argc = split_cmdline(bmo, &argv);
529 if (argc < 0)
530 die(_("Bad branch.%s.mergeoptions string: %s"), branch,
531 split_cmdline_strerror(argc));
532 argv = xrealloc(argv, sizeof(*argv) * (argc + 2));
533 memmove(argv + 1, argv, sizeof(*argv) * (argc + 1));
534 argc++;
535 argv[0] = "branch.*.mergeoptions";
536 parse_options(argc, argv, NULL, builtin_merge_options,
537 builtin_merge_usage, 0);
538 free(argv);
541 static int git_merge_config(const char *k, const char *v, void *cb)
543 int status;
545 if (branch && !prefixcmp(k, "branch.") &&
546 !prefixcmp(k + 7, branch) &&
547 !strcmp(k + 7 + strlen(branch), ".mergeoptions")) {
548 free(branch_mergeoptions);
549 branch_mergeoptions = xstrdup(v);
550 return 0;
553 if (!strcmp(k, "merge.diffstat") || !strcmp(k, "merge.stat"))
554 show_diffstat = git_config_bool(k, v);
555 else if (!strcmp(k, "pull.twohead"))
556 return git_config_string(&pull_twohead, k, v);
557 else if (!strcmp(k, "pull.octopus"))
558 return git_config_string(&pull_octopus, k, v);
559 else if (!strcmp(k, "merge.renormalize"))
560 option_renormalize = git_config_bool(k, v);
561 else if (!strcmp(k, "merge.ff")) {
562 int boolval = git_config_maybe_bool(k, v);
563 if (0 <= boolval) {
564 allow_fast_forward = boolval;
565 } else if (v && !strcmp(v, "only")) {
566 allow_fast_forward = 1;
567 fast_forward_only = 1;
568 } /* do not barf on values from future versions of git */
569 return 0;
570 } else if (!strcmp(k, "merge.defaulttoupstream")) {
571 default_to_upstream = git_config_bool(k, v);
572 return 0;
574 status = fmt_merge_msg_config(k, v, cb);
575 if (status)
576 return status;
577 return git_diff_ui_config(k, v, cb);
580 static int read_tree_trivial(unsigned char *common, unsigned char *head,
581 unsigned char *one)
583 int i, nr_trees = 0;
584 struct tree *trees[MAX_UNPACK_TREES];
585 struct tree_desc t[MAX_UNPACK_TREES];
586 struct unpack_trees_options opts;
588 memset(&opts, 0, sizeof(opts));
589 opts.head_idx = 2;
590 opts.src_index = &the_index;
591 opts.dst_index = &the_index;
592 opts.update = 1;
593 opts.verbose_update = 1;
594 opts.trivial_merges_only = 1;
595 opts.merge = 1;
596 trees[nr_trees] = parse_tree_indirect(common);
597 if (!trees[nr_trees++])
598 return -1;
599 trees[nr_trees] = parse_tree_indirect(head);
600 if (!trees[nr_trees++])
601 return -1;
602 trees[nr_trees] = parse_tree_indirect(one);
603 if (!trees[nr_trees++])
604 return -1;
605 opts.fn = threeway_merge;
606 cache_tree_free(&active_cache_tree);
607 for (i = 0; i < nr_trees; i++) {
608 parse_tree(trees[i]);
609 init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
611 if (unpack_trees(nr_trees, t, &opts))
612 return -1;
613 return 0;
616 static void write_tree_trivial(unsigned char *sha1)
618 if (write_cache_as_tree(sha1, 0, NULL))
619 die(_("git write-tree failed to write a tree"));
622 static const char *merge_argument(struct commit *commit)
624 if (commit)
625 return sha1_to_hex(commit->object.sha1);
626 else
627 return EMPTY_TREE_SHA1_HEX;
630 int try_merge_command(const char *strategy, size_t xopts_nr,
631 const char **xopts, struct commit_list *common,
632 const char *head_arg, struct commit_list *remotes)
634 const char **args;
635 int i = 0, x = 0, ret;
636 struct commit_list *j;
637 struct strbuf buf = STRBUF_INIT;
639 args = xmalloc((4 + xopts_nr + commit_list_count(common) +
640 commit_list_count(remotes)) * sizeof(char *));
641 strbuf_addf(&buf, "merge-%s", strategy);
642 args[i++] = buf.buf;
643 for (x = 0; x < xopts_nr; x++) {
644 char *s = xmalloc(strlen(xopts[x])+2+1);
645 strcpy(s, "--");
646 strcpy(s+2, xopts[x]);
647 args[i++] = s;
649 for (j = common; j; j = j->next)
650 args[i++] = xstrdup(merge_argument(j->item));
651 args[i++] = "--";
652 args[i++] = head_arg;
653 for (j = remotes; j; j = j->next)
654 args[i++] = xstrdup(merge_argument(j->item));
655 args[i] = NULL;
656 ret = run_command_v_opt(args, RUN_GIT_CMD);
657 strbuf_release(&buf);
658 i = 1;
659 for (x = 0; x < xopts_nr; x++)
660 free((void *)args[i++]);
661 for (j = common; j; j = j->next)
662 free((void *)args[i++]);
663 i += 2;
664 for (j = remotes; j; j = j->next)
665 free((void *)args[i++]);
666 free(args);
667 discard_cache();
668 if (read_cache() < 0)
669 die(_("failed to read the cache"));
670 resolve_undo_clear();
672 return ret;
675 static int try_merge_strategy(const char *strategy, struct commit_list *common,
676 struct commit *head, const char *head_arg)
678 int index_fd;
679 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
681 index_fd = hold_locked_index(lock, 1);
682 refresh_cache(REFRESH_QUIET);
683 if (active_cache_changed &&
684 (write_cache(index_fd, active_cache, active_nr) ||
685 commit_locked_index(lock)))
686 return error(_("Unable to write index."));
687 rollback_lock_file(lock);
689 if (!strcmp(strategy, "recursive") || !strcmp(strategy, "subtree")) {
690 int clean, x;
691 struct commit *result;
692 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
693 int index_fd;
694 struct commit_list *reversed = NULL;
695 struct merge_options o;
696 struct commit_list *j;
698 if (remoteheads->next) {
699 error(_("Not handling anything other than two heads merge."));
700 return 2;
703 init_merge_options(&o);
704 if (!strcmp(strategy, "subtree"))
705 o.subtree_shift = "";
707 o.renormalize = option_renormalize;
708 o.show_rename_progress =
709 show_progress == -1 ? isatty(2) : show_progress;
711 for (x = 0; x < xopts_nr; x++)
712 if (parse_merge_opt(&o, xopts[x]))
713 die(_("Unknown option for merge-recursive: -X%s"), xopts[x]);
715 o.branch1 = head_arg;
716 o.branch2 = merge_remote_util(remoteheads->item)->name;
718 for (j = common; j; j = j->next)
719 commit_list_insert(j->item, &reversed);
721 index_fd = hold_locked_index(lock, 1);
722 clean = merge_recursive(&o, head,
723 remoteheads->item, reversed, &result);
724 if (active_cache_changed &&
725 (write_cache(index_fd, active_cache, active_nr) ||
726 commit_locked_index(lock)))
727 die (_("unable to write %s"), get_index_file());
728 rollback_lock_file(lock);
729 return clean ? 0 : 1;
730 } else {
731 return try_merge_command(strategy, xopts_nr, xopts,
732 common, head_arg, remoteheads);
736 static void count_diff_files(struct diff_queue_struct *q,
737 struct diff_options *opt, void *data)
739 int *count = data;
741 (*count) += q->nr;
744 static int count_unmerged_entries(void)
746 int i, ret = 0;
748 for (i = 0; i < active_nr; i++)
749 if (ce_stage(active_cache[i]))
750 ret++;
752 return ret;
755 int checkout_fast_forward(const unsigned char *head, const unsigned char *remote)
757 struct tree *trees[MAX_UNPACK_TREES];
758 struct unpack_trees_options opts;
759 struct tree_desc t[MAX_UNPACK_TREES];
760 int i, fd, nr_trees = 0;
761 struct dir_struct dir;
762 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
764 refresh_cache(REFRESH_QUIET);
766 fd = hold_locked_index(lock_file, 1);
768 memset(&trees, 0, sizeof(trees));
769 memset(&opts, 0, sizeof(opts));
770 memset(&t, 0, sizeof(t));
771 if (overwrite_ignore) {
772 memset(&dir, 0, sizeof(dir));
773 dir.flags |= DIR_SHOW_IGNORED;
774 setup_standard_excludes(&dir);
775 opts.dir = &dir;
778 opts.head_idx = 1;
779 opts.src_index = &the_index;
780 opts.dst_index = &the_index;
781 opts.update = 1;
782 opts.verbose_update = 1;
783 opts.merge = 1;
784 opts.fn = twoway_merge;
785 setup_unpack_trees_porcelain(&opts, "merge");
787 trees[nr_trees] = parse_tree_indirect(head);
788 if (!trees[nr_trees++])
789 return -1;
790 trees[nr_trees] = parse_tree_indirect(remote);
791 if (!trees[nr_trees++])
792 return -1;
793 for (i = 0; i < nr_trees; i++) {
794 parse_tree(trees[i]);
795 init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
797 if (unpack_trees(nr_trees, t, &opts))
798 return -1;
799 if (write_cache(fd, active_cache, active_nr) ||
800 commit_locked_index(lock_file))
801 die(_("unable to write new index file"));
802 return 0;
805 static void split_merge_strategies(const char *string, struct strategy **list,
806 int *nr, int *alloc)
808 char *p, *q, *buf;
810 if (!string)
811 return;
813 buf = xstrdup(string);
814 q = buf;
815 for (;;) {
816 p = strchr(q, ' ');
817 if (!p) {
818 ALLOC_GROW(*list, *nr + 1, *alloc);
819 (*list)[(*nr)++].name = xstrdup(q);
820 free(buf);
821 return;
822 } else {
823 *p = '\0';
824 ALLOC_GROW(*list, *nr + 1, *alloc);
825 (*list)[(*nr)++].name = xstrdup(q);
826 q = ++p;
831 static void add_strategies(const char *string, unsigned attr)
833 struct strategy *list = NULL;
834 int list_alloc = 0, list_nr = 0, i;
836 memset(&list, 0, sizeof(list));
837 split_merge_strategies(string, &list, &list_nr, &list_alloc);
838 if (list) {
839 for (i = 0; i < list_nr; i++)
840 append_strategy(get_strategy(list[i].name));
841 return;
843 for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
844 if (all_strategy[i].attr & attr)
845 append_strategy(&all_strategy[i]);
849 static void write_merge_msg(struct strbuf *msg)
851 const char *filename = git_path("MERGE_MSG");
852 int fd = open(filename, O_WRONLY | O_CREAT, 0666);
853 if (fd < 0)
854 die_errno(_("Could not open '%s' for writing"),
855 filename);
856 if (write_in_full(fd, msg->buf, msg->len) != msg->len)
857 die_errno(_("Could not write to '%s'"), filename);
858 close(fd);
861 static void read_merge_msg(struct strbuf *msg)
863 const char *filename = git_path("MERGE_MSG");
864 strbuf_reset(msg);
865 if (strbuf_read_file(msg, filename, 0) < 0)
866 die_errno(_("Could not read from '%s'"), filename);
869 static void write_merge_state(void);
870 static void abort_commit(const char *err_msg)
872 if (err_msg)
873 error("%s", err_msg);
874 fprintf(stderr,
875 _("Not committing merge; use 'git commit' to complete the merge.\n"));
876 write_merge_state();
877 exit(1);
880 static void prepare_to_commit(void)
882 struct strbuf msg = STRBUF_INIT;
883 strbuf_addbuf(&msg, &merge_msg);
884 strbuf_addch(&msg, '\n');
885 write_merge_msg(&msg);
886 run_hook(get_index_file(), "prepare-commit-msg",
887 git_path("MERGE_MSG"), "merge", NULL, NULL);
888 if (option_edit) {
889 if (launch_editor(git_path("MERGE_MSG"), NULL, NULL))
890 abort_commit(NULL);
892 read_merge_msg(&msg);
893 stripspace(&msg, option_edit);
894 if (!msg.len)
895 abort_commit(_("Empty commit message."));
896 strbuf_release(&merge_msg);
897 strbuf_addbuf(&merge_msg, &msg);
898 strbuf_release(&msg);
901 static int merge_trivial(struct commit *head)
903 unsigned char result_tree[20], result_commit[20];
904 struct commit_list *parent = xmalloc(sizeof(*parent));
906 write_tree_trivial(result_tree);
907 printf(_("Wonderful.\n"));
908 parent->item = head;
909 parent->next = xmalloc(sizeof(*parent->next));
910 parent->next->item = remoteheads->item;
911 parent->next->next = NULL;
912 prepare_to_commit();
913 if (commit_tree(&merge_msg, result_tree, parent, result_commit, NULL))
914 die(_("failed to write commit object"));
915 finish(head, result_commit, "In-index merge");
916 drop_save();
917 return 0;
920 static int finish_automerge(struct commit *head,
921 struct commit_list *common,
922 unsigned char *result_tree,
923 const char *wt_strategy)
925 struct commit_list *parents = NULL, *j;
926 struct strbuf buf = STRBUF_INIT;
927 unsigned char result_commit[20];
929 free_commit_list(common);
930 if (allow_fast_forward) {
931 parents = remoteheads;
932 commit_list_insert(head, &parents);
933 parents = reduce_heads(parents);
934 } else {
935 struct commit_list **pptr = &parents;
937 pptr = &commit_list_insert(head,
938 pptr)->next;
939 for (j = remoteheads; j; j = j->next)
940 pptr = &commit_list_insert(j->item, pptr)->next;
942 strbuf_addch(&merge_msg, '\n');
943 prepare_to_commit();
944 free_commit_list(remoteheads);
945 if (commit_tree(&merge_msg, result_tree, parents, result_commit, NULL))
946 die(_("failed to write commit object"));
947 strbuf_addf(&buf, "Merge made by the '%s' strategy.", wt_strategy);
948 finish(head, result_commit, buf.buf);
949 strbuf_release(&buf);
950 drop_save();
951 return 0;
954 static int suggest_conflicts(int renormalizing)
956 const char *filename;
957 FILE *fp;
958 int pos;
960 filename = git_path("MERGE_MSG");
961 fp = fopen(filename, "a");
962 if (!fp)
963 die_errno(_("Could not open '%s' for writing"), filename);
964 fprintf(fp, "\nConflicts:\n");
965 for (pos = 0; pos < active_nr; pos++) {
966 struct cache_entry *ce = active_cache[pos];
968 if (ce_stage(ce)) {
969 fprintf(fp, "\t%s\n", ce->name);
970 while (pos + 1 < active_nr &&
971 !strcmp(ce->name,
972 active_cache[pos + 1]->name))
973 pos++;
976 fclose(fp);
977 rerere(allow_rerere_auto);
978 printf(_("Automatic merge failed; "
979 "fix conflicts and then commit the result.\n"));
980 return 1;
983 static struct commit *is_old_style_invocation(int argc, const char **argv,
984 const unsigned char *head)
986 struct commit *second_token = NULL;
987 if (argc > 2) {
988 unsigned char second_sha1[20];
990 if (get_sha1(argv[1], second_sha1))
991 return NULL;
992 second_token = lookup_commit_reference_gently(second_sha1, 0);
993 if (!second_token)
994 die(_("'%s' is not a commit"), argv[1]);
995 if (hashcmp(second_token->object.sha1, head))
996 return NULL;
998 return second_token;
1001 static int evaluate_result(void)
1003 int cnt = 0;
1004 struct rev_info rev;
1006 /* Check how many files differ. */
1007 init_revisions(&rev, "");
1008 setup_revisions(0, NULL, &rev, NULL);
1009 rev.diffopt.output_format |=
1010 DIFF_FORMAT_CALLBACK;
1011 rev.diffopt.format_callback = count_diff_files;
1012 rev.diffopt.format_callback_data = &cnt;
1013 run_diff_files(&rev, 0);
1016 * Check how many unmerged entries are
1017 * there.
1019 cnt += count_unmerged_entries();
1021 return cnt;
1025 * Pretend as if the user told us to merge with the tracking
1026 * branch we have for the upstream of the current branch
1028 static int setup_with_upstream(const char ***argv)
1030 struct branch *branch = branch_get(NULL);
1031 int i;
1032 const char **args;
1034 if (!branch)
1035 die(_("No current branch."));
1036 if (!branch->remote)
1037 die(_("No remote for the current branch."));
1038 if (!branch->merge_nr)
1039 die(_("No default upstream defined for the current branch."));
1041 args = xcalloc(branch->merge_nr + 1, sizeof(char *));
1042 for (i = 0; i < branch->merge_nr; i++) {
1043 if (!branch->merge[i]->dst)
1044 die(_("No remote tracking branch for %s from %s"),
1045 branch->merge[i]->src, branch->remote_name);
1046 args[i] = branch->merge[i]->dst;
1048 args[i] = NULL;
1049 *argv = args;
1050 return i;
1053 static void write_merge_state(void)
1055 const char *filename;
1056 int fd;
1057 struct commit_list *j;
1058 struct strbuf buf = STRBUF_INIT;
1060 for (j = remoteheads; j; j = j->next) {
1061 unsigned const char *sha1;
1062 struct commit *c = j->item;
1063 if (c->util && merge_remote_util(c)->obj) {
1064 sha1 = merge_remote_util(c)->obj->sha1;
1065 } else {
1066 sha1 = c->object.sha1;
1068 strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
1070 filename = git_path("MERGE_HEAD");
1071 fd = open(filename, O_WRONLY | O_CREAT, 0666);
1072 if (fd < 0)
1073 die_errno(_("Could not open '%s' for writing"), filename);
1074 if (write_in_full(fd, buf.buf, buf.len) != buf.len)
1075 die_errno(_("Could not write to '%s'"), filename);
1076 close(fd);
1077 strbuf_addch(&merge_msg, '\n');
1078 write_merge_msg(&merge_msg);
1080 filename = git_path("MERGE_MODE");
1081 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
1082 if (fd < 0)
1083 die_errno(_("Could not open '%s' for writing"), filename);
1084 strbuf_reset(&buf);
1085 if (!allow_fast_forward)
1086 strbuf_addf(&buf, "no-ff");
1087 if (write_in_full(fd, buf.buf, buf.len) != buf.len)
1088 die_errno(_("Could not write to '%s'"), filename);
1089 close(fd);
1092 int cmd_merge(int argc, const char **argv, const char *prefix)
1094 unsigned char result_tree[20];
1095 unsigned char stash[20];
1096 unsigned char head_sha1[20];
1097 struct commit *head_commit;
1098 struct strbuf buf = STRBUF_INIT;
1099 const char *head_arg;
1100 int flag, i, ret = 0;
1101 int best_cnt = -1, merge_was_ok = 0, automerge_was_ok = 0;
1102 struct commit_list *common = NULL;
1103 const char *best_strategy = NULL, *wt_strategy = NULL;
1104 struct commit_list **remotes = &remoteheads;
1105 void *branch_to_free;
1107 if (argc == 2 && !strcmp(argv[1], "-h"))
1108 usage_with_options(builtin_merge_usage, builtin_merge_options);
1111 * Check if we are _not_ on a detached HEAD, i.e. if there is a
1112 * current branch.
1114 branch = branch_to_free = resolve_refdup("HEAD", head_sha1, 0, &flag);
1115 if (branch && !prefixcmp(branch, "refs/heads/"))
1116 branch += 11;
1117 if (!branch || is_null_sha1(head_sha1))
1118 head_commit = NULL;
1119 else
1120 head_commit = lookup_commit_or_die(head_sha1, "HEAD");
1122 git_config(git_merge_config, NULL);
1124 if (branch_mergeoptions)
1125 parse_branch_merge_options(branch_mergeoptions);
1126 argc = parse_options(argc, argv, prefix, builtin_merge_options,
1127 builtin_merge_usage, 0);
1128 if (shortlog_len < 0)
1129 shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
1131 if (verbosity < 0 && show_progress == -1)
1132 show_progress = 0;
1134 if (abort_current_merge) {
1135 int nargc = 2;
1136 const char *nargv[] = {"reset", "--merge", NULL};
1138 if (!file_exists(git_path("MERGE_HEAD")))
1139 die(_("There is no merge to abort (MERGE_HEAD missing)."));
1141 /* Invoke 'git reset --merge' */
1142 ret = cmd_reset(nargc, nargv, prefix);
1143 goto done;
1146 if (read_cache_unmerged())
1147 die_resolve_conflict("merge");
1149 if (file_exists(git_path("MERGE_HEAD"))) {
1151 * There is no unmerged entry, don't advise 'git
1152 * add/rm <file>', just 'git commit'.
1154 if (advice_resolve_conflict)
1155 die(_("You have not concluded your merge (MERGE_HEAD exists).\n"
1156 "Please, commit your changes before you can merge."));
1157 else
1158 die(_("You have not concluded your merge (MERGE_HEAD exists)."));
1160 if (file_exists(git_path("CHERRY_PICK_HEAD"))) {
1161 if (advice_resolve_conflict)
1162 die(_("You have not concluded your cherry-pick (CHERRY_PICK_HEAD exists).\n"
1163 "Please, commit your changes before you can merge."));
1164 else
1165 die(_("You have not concluded your cherry-pick (CHERRY_PICK_HEAD exists)."));
1167 resolve_undo_clear();
1169 if (verbosity < 0)
1170 show_diffstat = 0;
1172 if (squash) {
1173 if (!allow_fast_forward)
1174 die(_("You cannot combine --squash with --no-ff."));
1175 option_commit = 0;
1178 if (!allow_fast_forward && fast_forward_only)
1179 die(_("You cannot combine --no-ff with --ff-only."));
1181 if (!abort_current_merge) {
1182 if (!argc) {
1183 if (default_to_upstream)
1184 argc = setup_with_upstream(&argv);
1185 else
1186 die(_("No commit specified and merge.defaultToUpstream not set."));
1187 } else if (argc == 1 && !strcmp(argv[0], "-"))
1188 argv[0] = "@{-1}";
1190 if (!argc)
1191 usage_with_options(builtin_merge_usage,
1192 builtin_merge_options);
1195 * This could be traditional "merge <msg> HEAD <commit>..." and
1196 * the way we can tell it is to see if the second token is HEAD,
1197 * but some people might have misused the interface and used a
1198 * committish that is the same as HEAD there instead.
1199 * Traditional format never would have "-m" so it is an
1200 * additional safety measure to check for it.
1203 if (!have_message && head_commit &&
1204 is_old_style_invocation(argc, argv, head_commit->object.sha1)) {
1205 strbuf_addstr(&merge_msg, argv[0]);
1206 head_arg = argv[1];
1207 argv += 2;
1208 argc -= 2;
1209 } else if (!head_commit) {
1210 struct commit *remote_head;
1212 * If the merged head is a valid one there is no reason
1213 * to forbid "git merge" into a branch yet to be born.
1214 * We do the same for "git pull".
1216 if (argc != 1)
1217 die(_("Can merge only exactly one commit into "
1218 "empty head"));
1219 if (squash)
1220 die(_("Squash commit into empty head not supported yet"));
1221 if (!allow_fast_forward)
1222 die(_("Non-fast-forward commit does not make sense into "
1223 "an empty head"));
1224 remote_head = get_merge_parent(argv[0]);
1225 if (!remote_head)
1226 die(_("%s - not something we can merge"), argv[0]);
1227 read_empty(remote_head->object.sha1, 0);
1228 update_ref("initial pull", "HEAD", remote_head->object.sha1,
1229 NULL, 0, DIE_ON_ERR);
1230 goto done;
1231 } else {
1232 struct strbuf merge_names = STRBUF_INIT;
1234 /* We are invoked directly as the first-class UI. */
1235 head_arg = "HEAD";
1238 * All the rest are the commits being merged; prepare
1239 * the standard merge summary message to be appended
1240 * to the given message.
1242 for (i = 0; i < argc; i++)
1243 merge_name(argv[i], &merge_names);
1245 if (!have_message || shortlog_len) {
1246 struct fmt_merge_msg_opts opts;
1247 memset(&opts, 0, sizeof(opts));
1248 opts.add_title = !have_message;
1249 opts.shortlog_len = shortlog_len;
1251 fmt_merge_msg(&merge_names, &merge_msg, &opts);
1252 if (merge_msg.len)
1253 strbuf_setlen(&merge_msg, merge_msg.len - 1);
1257 if (!head_commit || !argc)
1258 usage_with_options(builtin_merge_usage,
1259 builtin_merge_options);
1261 strbuf_addstr(&buf, "merge");
1262 for (i = 0; i < argc; i++)
1263 strbuf_addf(&buf, " %s", argv[i]);
1264 setenv("GIT_REFLOG_ACTION", buf.buf, 0);
1265 strbuf_reset(&buf);
1267 for (i = 0; i < argc; i++) {
1268 struct commit *commit = get_merge_parent(argv[i]);
1269 if (!commit)
1270 die(_("%s - not something we can merge"), argv[i]);
1271 remotes = &commit_list_insert(commit, remotes)->next;
1272 strbuf_addf(&buf, "GITHEAD_%s",
1273 sha1_to_hex(commit->object.sha1));
1274 setenv(buf.buf, argv[i], 1);
1275 strbuf_reset(&buf);
1276 if (merge_remote_util(commit) &&
1277 merge_remote_util(commit)->obj &&
1278 merge_remote_util(commit)->obj->type == OBJ_TAG) {
1279 option_edit = 1;
1280 allow_fast_forward = 0;
1284 if (!use_strategies) {
1285 if (!remoteheads->next)
1286 add_strategies(pull_twohead, DEFAULT_TWOHEAD);
1287 else
1288 add_strategies(pull_octopus, DEFAULT_OCTOPUS);
1291 for (i = 0; i < use_strategies_nr; i++) {
1292 if (use_strategies[i]->attr & NO_FAST_FORWARD)
1293 allow_fast_forward = 0;
1294 if (use_strategies[i]->attr & NO_TRIVIAL)
1295 allow_trivial = 0;
1298 if (!remoteheads->next)
1299 common = get_merge_bases(head_commit, remoteheads->item, 1);
1300 else {
1301 struct commit_list *list = remoteheads;
1302 commit_list_insert(head_commit, &list);
1303 common = get_octopus_merge_bases(list);
1304 free(list);
1307 update_ref("updating ORIG_HEAD", "ORIG_HEAD", head_commit->object.sha1,
1308 NULL, 0, DIE_ON_ERR);
1310 if (!common)
1311 ; /* No common ancestors found. We need a real merge. */
1312 else if (!remoteheads->next && !common->next &&
1313 common->item == remoteheads->item) {
1315 * If head can reach all the merge then we are up to date.
1316 * but first the most common case of merging one remote.
1318 finish_up_to_date("Already up-to-date.");
1319 goto done;
1320 } else if (allow_fast_forward && !remoteheads->next &&
1321 !common->next &&
1322 !hashcmp(common->item->object.sha1, head_commit->object.sha1)) {
1323 /* Again the most common case of merging one remote. */
1324 struct strbuf msg = STRBUF_INIT;
1325 struct commit *commit;
1326 char hex[41];
1328 strcpy(hex, find_unique_abbrev(head_commit->object.sha1, DEFAULT_ABBREV));
1330 if (verbosity >= 0)
1331 printf(_("Updating %s..%s\n"),
1332 hex,
1333 find_unique_abbrev(remoteheads->item->object.sha1,
1334 DEFAULT_ABBREV));
1335 strbuf_addstr(&msg, "Fast-forward");
1336 if (have_message)
1337 strbuf_addstr(&msg,
1338 " (no commit created; -m option ignored)");
1339 commit = remoteheads->item;
1340 if (!commit) {
1341 ret = 1;
1342 goto done;
1345 if (checkout_fast_forward(head_commit->object.sha1,
1346 commit->object.sha1)) {
1347 ret = 1;
1348 goto done;
1351 finish(head_commit, commit->object.sha1, msg.buf);
1352 drop_save();
1353 goto done;
1354 } else if (!remoteheads->next && common->next)
1357 * We are not doing octopus and not fast-forward. Need
1358 * a real merge.
1360 else if (!remoteheads->next && !common->next && option_commit) {
1362 * We are not doing octopus, not fast-forward, and have
1363 * only one common.
1365 refresh_cache(REFRESH_QUIET);
1366 if (allow_trivial && !fast_forward_only) {
1367 /* See if it is really trivial. */
1368 git_committer_info(IDENT_ERROR_ON_NO_NAME);
1369 printf(_("Trying really trivial in-index merge...\n"));
1370 if (!read_tree_trivial(common->item->object.sha1,
1371 head_commit->object.sha1,
1372 remoteheads->item->object.sha1)) {
1373 ret = merge_trivial(head_commit);
1374 goto done;
1376 printf(_("Nope.\n"));
1378 } else {
1380 * An octopus. If we can reach all the remote we are up
1381 * to date.
1383 int up_to_date = 1;
1384 struct commit_list *j;
1386 for (j = remoteheads; j; j = j->next) {
1387 struct commit_list *common_one;
1390 * Here we *have* to calculate the individual
1391 * merge_bases again, otherwise "git merge HEAD^
1392 * HEAD^^" would be missed.
1394 common_one = get_merge_bases(head_commit, j->item, 1);
1395 if (hashcmp(common_one->item->object.sha1,
1396 j->item->object.sha1)) {
1397 up_to_date = 0;
1398 break;
1401 if (up_to_date) {
1402 finish_up_to_date("Already up-to-date. Yeeah!");
1403 goto done;
1407 if (fast_forward_only)
1408 die(_("Not possible to fast-forward, aborting."));
1410 /* We are going to make a new commit. */
1411 git_committer_info(IDENT_ERROR_ON_NO_NAME);
1414 * At this point, we need a real merge. No matter what strategy
1415 * we use, it would operate on the index, possibly affecting the
1416 * working tree, and when resolved cleanly, have the desired
1417 * tree in the index -- this means that the index must be in
1418 * sync with the head commit. The strategies are responsible
1419 * to ensure this.
1421 if (use_strategies_nr == 1 ||
1423 * Stash away the local changes so that we can try more than one.
1425 save_state(stash))
1426 hashcpy(stash, null_sha1);
1428 for (i = 0; i < use_strategies_nr; i++) {
1429 int ret;
1430 if (i) {
1431 printf(_("Rewinding the tree to pristine...\n"));
1432 restore_state(head_commit->object.sha1, stash);
1434 if (use_strategies_nr != 1)
1435 printf(_("Trying merge strategy %s...\n"),
1436 use_strategies[i]->name);
1438 * Remember which strategy left the state in the working
1439 * tree.
1441 wt_strategy = use_strategies[i]->name;
1443 ret = try_merge_strategy(use_strategies[i]->name,
1444 common, head_commit, head_arg);
1445 if (!option_commit && !ret) {
1446 merge_was_ok = 1;
1448 * This is necessary here just to avoid writing
1449 * the tree, but later we will *not* exit with
1450 * status code 1 because merge_was_ok is set.
1452 ret = 1;
1455 if (ret) {
1457 * The backend exits with 1 when conflicts are
1458 * left to be resolved, with 2 when it does not
1459 * handle the given merge at all.
1461 if (ret == 1) {
1462 int cnt = evaluate_result();
1464 if (best_cnt <= 0 || cnt <= best_cnt) {
1465 best_strategy = use_strategies[i]->name;
1466 best_cnt = cnt;
1469 if (merge_was_ok)
1470 break;
1471 else
1472 continue;
1475 /* Automerge succeeded. */
1476 write_tree_trivial(result_tree);
1477 automerge_was_ok = 1;
1478 break;
1482 * If we have a resulting tree, that means the strategy module
1483 * auto resolved the merge cleanly.
1485 if (automerge_was_ok) {
1486 ret = finish_automerge(head_commit, common, result_tree,
1487 wt_strategy);
1488 goto done;
1492 * Pick the result from the best strategy and have the user fix
1493 * it up.
1495 if (!best_strategy) {
1496 restore_state(head_commit->object.sha1, stash);
1497 if (use_strategies_nr > 1)
1498 fprintf(stderr,
1499 _("No merge strategy handled the merge.\n"));
1500 else
1501 fprintf(stderr, _("Merge with strategy %s failed.\n"),
1502 use_strategies[0]->name);
1503 ret = 2;
1504 goto done;
1505 } else if (best_strategy == wt_strategy)
1506 ; /* We already have its result in the working tree. */
1507 else {
1508 printf(_("Rewinding the tree to pristine...\n"));
1509 restore_state(head_commit->object.sha1, stash);
1510 printf(_("Using the %s to prepare resolving by hand.\n"),
1511 best_strategy);
1512 try_merge_strategy(best_strategy, common, head_commit, head_arg);
1515 if (squash)
1516 finish(head_commit, NULL, NULL);
1517 else
1518 write_merge_state();
1520 if (merge_was_ok)
1521 fprintf(stderr, _("Automatic merge went well; "
1522 "stopped before committing as requested\n"));
1523 else
1524 ret = suggest_conflicts(option_renormalize);
1526 done:
1527 free(branch_to_free);
1528 return ret;