unpack_trees: group error messages by type
[git/git.git] / builtin / merge.c
CommitLineData
1c7b76be
MV
1/*
2 * Builtin "git merge"
3 *
4 * Copyright (c) 2008 Miklos Vajna <vmiklos@frugalware.org>
5 *
6 * Based on git-merge.sh by Junio C Hamano.
7 */
8
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"
fcab40a3 24#include "rerere.h"
87091b49 25#include "help.h"
18668f53 26#include "merge-recursive.h"
cfc5789a 27#include "resolve-undo.h"
1c7b76be
MV
28
29#define DEFAULT_TWOHEAD (1<<0)
30#define DEFAULT_OCTOPUS (1<<1)
31#define NO_FAST_FORWARD (1<<2)
32#define NO_TRIVIAL (1<<3)
33
34struct strategy {
35 const char *name;
36 unsigned attr;
37};
38
39static const char * const builtin_merge_usage[] = {
34263de0
AP
40 "git merge [options] <remote>...",
41 "git merge [options] <msg> HEAD <remote>",
1c7b76be
MV
42 NULL
43};
44
45static int show_diffstat = 1, option_log, squash;
46static int option_commit = 1, allow_fast_forward = 1;
13474835 47static int fast_forward_only;
1c7b76be
MV
48static int allow_trivial = 1, have_message;
49static struct strbuf merge_msg;
50static struct commit_list *remoteheads;
51static unsigned char head[20], stash[20];
52static struct strategy **use_strategies;
53static size_t use_strategies_nr, use_strategies_alloc;
8cc5b290
AP
54static const char **xopts;
55static size_t xopts_nr, xopts_alloc;
1c7b76be 56static const char *branch;
7f87aff2 57static int verbosity;
cb6020bb 58static int allow_rerere_auto;
1c7b76be
MV
59
60static struct strategy all_strategy[] = {
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MV
61 { "recursive", DEFAULT_TWOHEAD | NO_TRIVIAL },
62 { "octopus", DEFAULT_OCTOPUS },
63 { "resolve", 0 },
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MV
64 { "ours", NO_FAST_FORWARD | NO_TRIVIAL },
65 { "subtree", NO_FAST_FORWARD | NO_TRIVIAL },
66};
67
68static const char *pull_twohead, *pull_octopus;
69
70static int option_parse_message(const struct option *opt,
71 const char *arg, int unset)
72{
73 struct strbuf *buf = opt->value;
74
75 if (unset)
76 strbuf_setlen(buf, 0);
74f5b7fb 77 else if (arg) {
ce9d823b 78 strbuf_addf(buf, "%s%s", buf->len ? "\n\n" : "", arg);
1c7b76be 79 have_message = 1;
74f5b7fb
MB
80 } else
81 return error("switch `m' requires a value");
1c7b76be
MV
82 return 0;
83}
84
85static struct strategy *get_strategy(const char *name)
86{
87 int i;
87091b49
MV
88 struct strategy *ret;
89 static struct cmdnames main_cmds, other_cmds;
e321180e 90 static int loaded;
1c7b76be
MV
91
92 if (!name)
93 return NULL;
94
95 for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
96 if (!strcmp(name, all_strategy[i].name))
97 return &all_strategy[i];
1719b5e4 98
e321180e 99 if (!loaded) {
87091b49 100 struct cmdnames not_strategies;
e321180e 101 loaded = 1;
87091b49 102
87091b49 103 memset(&not_strategies, 0, sizeof(struct cmdnames));
e321180e 104 load_command_list("git-merge-", &main_cmds, &other_cmds);
87091b49
MV
105 for (i = 0; i < main_cmds.cnt; i++) {
106 int j, found = 0;
107 struct cmdname *ent = main_cmds.names[i];
108 for (j = 0; j < ARRAY_SIZE(all_strategy); j++)
109 if (!strncmp(ent->name, all_strategy[j].name, ent->len)
110 && !all_strategy[j].name[ent->len])
111 found = 1;
112 if (!found)
113 add_cmdname(&not_strategies, ent->name, ent->len);
87091b49 114 }
ed874656 115 exclude_cmds(&main_cmds, &not_strategies);
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MV
116 }
117 if (!is_in_cmdlist(&main_cmds, name) && !is_in_cmdlist(&other_cmds, name)) {
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JH
118 fprintf(stderr, "Could not find merge strategy '%s'.\n", name);
119 fprintf(stderr, "Available strategies are:");
120 for (i = 0; i < main_cmds.cnt; i++)
121 fprintf(stderr, " %s", main_cmds.names[i]->name);
122 fprintf(stderr, ".\n");
123 if (other_cmds.cnt) {
124 fprintf(stderr, "Available custom strategies are:");
125 for (i = 0; i < other_cmds.cnt; i++)
126 fprintf(stderr, " %s", other_cmds.names[i]->name);
127 fprintf(stderr, ".\n");
128 }
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MV
129 exit(1);
130 }
131
19d4b416 132 ret = xcalloc(1, sizeof(struct strategy));
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MV
133 ret->name = xstrdup(name);
134 return ret;
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MV
135}
136
137static void append_strategy(struct strategy *s)
138{
139 ALLOC_GROW(use_strategies, use_strategies_nr + 1, use_strategies_alloc);
140 use_strategies[use_strategies_nr++] = s;
141}
142
143static int option_parse_strategy(const struct option *opt,
144 const char *name, int unset)
145{
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MV
146 if (unset)
147 return 0;
148
1719b5e4 149 append_strategy(get_strategy(name));
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MV
150 return 0;
151}
152
8cc5b290
AP
153static int option_parse_x(const struct option *opt,
154 const char *arg, int unset)
155{
156 if (unset)
157 return 0;
158
159 ALLOC_GROW(xopts, xopts_nr + 1, xopts_alloc);
160 xopts[xopts_nr++] = xstrdup(arg);
161 return 0;
162}
163
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MV
164static int option_parse_n(const struct option *opt,
165 const char *arg, int unset)
166{
167 show_diffstat = unset;
168 return 0;
169}
170
171static struct option builtin_merge_options[] = {
172 { OPTION_CALLBACK, 'n', NULL, NULL, NULL,
173 "do not show a diffstat at the end of the merge",
174 PARSE_OPT_NOARG, option_parse_n },
175 OPT_BOOLEAN(0, "stat", &show_diffstat,
176 "show a diffstat at the end of the merge"),
177 OPT_BOOLEAN(0, "summary", &show_diffstat, "(synonym to --stat)"),
178 OPT_BOOLEAN(0, "log", &option_log,
179 "add list of one-line log to merge commit message"),
180 OPT_BOOLEAN(0, "squash", &squash,
181 "create a single commit instead of doing a merge"),
182 OPT_BOOLEAN(0, "commit", &option_commit,
183 "perform a commit if the merge succeeds (default)"),
184 OPT_BOOLEAN(0, "ff", &allow_fast_forward,
a75d7b54 185 "allow fast-forward (default)"),
13474835 186 OPT_BOOLEAN(0, "ff-only", &fast_forward_only,
4d8c3258 187 "abort if fast-forward is not possible"),
cb6020bb 188 OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
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MV
189 OPT_CALLBACK('s', "strategy", &use_strategies, "strategy",
190 "merge strategy to use", option_parse_strategy),
8cc5b290
AP
191 OPT_CALLBACK('X', "strategy-option", &xopts, "option=value",
192 "option for selected merge strategy", option_parse_x),
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MV
193 OPT_CALLBACK('m', "message", &merge_msg, "message",
194 "message to be used for the merge commit (if any)",
195 option_parse_message),
7f87aff2 196 OPT__VERBOSITY(&verbosity),
1c7b76be
MV
197 OPT_END()
198};
199
200/* Cleans up metadata that is uninteresting after a succeeded merge. */
201static void drop_save(void)
202{
203 unlink(git_path("MERGE_HEAD"));
204 unlink(git_path("MERGE_MSG"));
cf10f9fd 205 unlink(git_path("MERGE_MODE"));
1c7b76be
MV
206}
207
208static void save_state(void)
209{
210 int len;
211 struct child_process cp;
212 struct strbuf buffer = STRBUF_INIT;
213 const char *argv[] = {"stash", "create", NULL};
214
215 memset(&cp, 0, sizeof(cp));
216 cp.argv = argv;
217 cp.out = -1;
218 cp.git_cmd = 1;
219
220 if (start_command(&cp))
221 die("could not run stash.");
222 len = strbuf_read(&buffer, cp.out, 1024);
223 close(cp.out);
224
225 if (finish_command(&cp) || len < 0)
226 die("stash failed");
227 else if (!len)
228 return;
229 strbuf_setlen(&buffer, buffer.len-1);
230 if (get_sha1(buffer.buf, stash))
231 die("not a valid object: %s", buffer.buf);
232}
233
234static void reset_hard(unsigned const char *sha1, int verbose)
235{
236 int i = 0;
237 const char *args[6];
238
239 args[i++] = "read-tree";
240 if (verbose)
241 args[i++] = "-v";
242 args[i++] = "--reset";
243 args[i++] = "-u";
244 args[i++] = sha1_to_hex(sha1);
245 args[i] = NULL;
246
247 if (run_command_v_opt(args, RUN_GIT_CMD))
248 die("read-tree failed");
249}
250
251static void restore_state(void)
252{
f285a2d7 253 struct strbuf sb = STRBUF_INIT;
1c7b76be
MV
254 const char *args[] = { "stash", "apply", NULL, NULL };
255
256 if (is_null_sha1(stash))
257 return;
258
259 reset_hard(head, 1);
260
1c7b76be
MV
261 args[2] = sha1_to_hex(stash);
262
263 /*
264 * It is OK to ignore error here, for example when there was
265 * nothing to restore.
266 */
267 run_command_v_opt(args, RUN_GIT_CMD);
268
269 strbuf_release(&sb);
270 refresh_cache(REFRESH_QUIET);
271}
272
273/* This is called when no merge was necessary. */
274static void finish_up_to_date(const char *msg)
275{
7f87aff2
TA
276 if (verbosity >= 0)
277 printf("%s%s\n", squash ? " (nothing to squash)" : "", msg);
1c7b76be
MV
278 drop_save();
279}
280
281static void squash_message(void)
282{
283 struct rev_info rev;
284 struct commit *commit;
f285a2d7 285 struct strbuf out = STRBUF_INIT;
1c7b76be
MV
286 struct commit_list *j;
287 int fd;
dd2e794a 288 struct pretty_print_context ctx = {0};
1c7b76be
MV
289
290 printf("Squash commit -- not updating HEAD\n");
291 fd = open(git_path("SQUASH_MSG"), O_WRONLY | O_CREAT, 0666);
292 if (fd < 0)
0721c314 293 die_errno("Could not write to '%s'", git_path("SQUASH_MSG"));
1c7b76be
MV
294
295 init_revisions(&rev, NULL);
296 rev.ignore_merges = 1;
297 rev.commit_format = CMIT_FMT_MEDIUM;
298
299 commit = lookup_commit(head);
300 commit->object.flags |= UNINTERESTING;
301 add_pending_object(&rev, &commit->object, NULL);
302
303 for (j = remoteheads; j; j = j->next)
304 add_pending_object(&rev, &j->item->object, NULL);
305
306 setup_revisions(0, NULL, &rev, NULL);
307 if (prepare_revision_walk(&rev))
308 die("revision walk setup failed");
309
dd2e794a
TR
310 ctx.abbrev = rev.abbrev;
311 ctx.date_mode = rev.date_mode;
312
1c7b76be
MV
313 strbuf_addstr(&out, "Squashed commit of the following:\n");
314 while ((commit = get_revision(&rev)) != NULL) {
315 strbuf_addch(&out, '\n');
316 strbuf_addf(&out, "commit %s\n",
317 sha1_to_hex(commit->object.sha1));
dd2e794a 318 pretty_print_commit(rev.commit_format, commit, &out, &ctx);
1c7b76be 319 }
47d32af2 320 if (write(fd, out.buf, out.len) < 0)
d824cbba 321 die_errno("Writing SQUASH_MSG");
47d32af2 322 if (close(fd))
d824cbba 323 die_errno("Finishing SQUASH_MSG");
1c7b76be
MV
324 strbuf_release(&out);
325}
326
1c7b76be
MV
327static void finish(const unsigned char *new_head, const char *msg)
328{
f285a2d7 329 struct strbuf reflog_message = STRBUF_INIT;
1c7b76be 330
1c7b76be
MV
331 if (!msg)
332 strbuf_addstr(&reflog_message, getenv("GIT_REFLOG_ACTION"));
333 else {
7f87aff2
TA
334 if (verbosity >= 0)
335 printf("%s\n", msg);
1c7b76be
MV
336 strbuf_addf(&reflog_message, "%s: %s",
337 getenv("GIT_REFLOG_ACTION"), msg);
338 }
339 if (squash) {
340 squash_message();
341 } else {
7f87aff2 342 if (verbosity >= 0 && !merge_msg.len)
1c7b76be
MV
343 printf("No merge message -- not updating HEAD\n");
344 else {
345 const char *argv_gc_auto[] = { "gc", "--auto", NULL };
346 update_ref(reflog_message.buf, "HEAD",
347 new_head, head, 0,
348 DIE_ON_ERR);
349 /*
350 * We ignore errors in 'gc --auto', since the
351 * user should see them.
352 */
353 run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
354 }
355 }
356 if (new_head && show_diffstat) {
357 struct diff_options opts;
358 diff_setup(&opts);
359 opts.output_format |=
360 DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
361 opts.detect_rename = DIFF_DETECT_RENAME;
362 if (diff_use_color_default > 0)
363 DIFF_OPT_SET(&opts, COLOR_DIFF);
364 if (diff_setup_done(&opts) < 0)
365 die("diff_setup_done failed");
366 diff_tree_sha1(head, new_head, "", &opts);
367 diffcore_std(&opts);
368 diff_flush(&opts);
369 }
370
371 /* Run a post-merge hook */
ae98a008 372 run_hook(NULL, "post-merge", squash ? "1" : "0", NULL);
1c7b76be
MV
373
374 strbuf_release(&reflog_message);
375}
376
377/* Get the name for the merge commit's message. */
378static void merge_name(const char *remote, struct strbuf *msg)
379{
380 struct object *remote_head;
381 unsigned char branch_head[20], buf_sha[20];
f285a2d7 382 struct strbuf buf = STRBUF_INIT;
c9717ee9 383 struct strbuf bname = STRBUF_INIT;
1c7b76be 384 const char *ptr;
751c5974 385 char *found_ref;
1c7b76be
MV
386 int len, early;
387
a552de75
JH
388 strbuf_branchname(&bname, remote);
389 remote = bname.buf;
c9717ee9 390
1c7b76be
MV
391 memset(branch_head, 0, sizeof(branch_head));
392 remote_head = peel_to_type(remote, 0, NULL, OBJ_COMMIT);
393 if (!remote_head)
394 die("'%s' does not point to a commit", remote);
395
751c5974
JK
396 if (dwim_ref(remote, strlen(remote), branch_head, &found_ref) > 0) {
397 if (!prefixcmp(found_ref, "refs/heads/")) {
398 strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
399 sha1_to_hex(branch_head), remote);
400 goto cleanup;
401 }
69a8b7c7
JK
402 if (!prefixcmp(found_ref, "refs/remotes/")) {
403 strbuf_addf(msg, "%s\t\tremote branch '%s' of .\n",
404 sha1_to_hex(branch_head), remote);
405 goto cleanup;
406 }
1c7b76be
MV
407 }
408
409 /* See if remote matches <name>^^^.. or <name>~<number> */
410 for (len = 0, ptr = remote + strlen(remote);
411 remote < ptr && ptr[-1] == '^';
412 ptr--)
413 len++;
414 if (len)
415 early = 1;
416 else {
417 early = 0;
418 ptr = strrchr(remote, '~');
419 if (ptr) {
420 int seen_nonzero = 0;
421
422 len++; /* count ~ */
423 while (*++ptr && isdigit(*ptr)) {
424 seen_nonzero |= (*ptr != '0');
425 len++;
426 }
427 if (*ptr)
428 len = 0; /* not ...~<number> */
429 else if (seen_nonzero)
430 early = 1;
431 else if (len == 1)
432 early = 1; /* "name~" is "name~1"! */
433 }
434 }
435 if (len) {
436 struct strbuf truname = STRBUF_INIT;
437 strbuf_addstr(&truname, "refs/heads/");
438 strbuf_addstr(&truname, remote);
9b6bf4d5 439 strbuf_setlen(&truname, truname.len - len);
2af202be 440 if (resolve_ref(truname.buf, buf_sha, 0, NULL)) {
1c7b76be
MV
441 strbuf_addf(msg,
442 "%s\t\tbranch '%s'%s of .\n",
443 sha1_to_hex(remote_head->sha1),
9b6bf4d5 444 truname.buf + 11,
1c7b76be 445 (early ? " (early part)" : ""));
c9717ee9
JH
446 strbuf_release(&truname);
447 goto cleanup;
1c7b76be
MV
448 }
449 }
450
451 if (!strcmp(remote, "FETCH_HEAD") &&
452 !access(git_path("FETCH_HEAD"), R_OK)) {
453 FILE *fp;
f285a2d7 454 struct strbuf line = STRBUF_INIT;
1c7b76be
MV
455 char *ptr;
456
1c7b76be
MV
457 fp = fopen(git_path("FETCH_HEAD"), "r");
458 if (!fp)
d824cbba
TR
459 die_errno("could not open '%s' for reading",
460 git_path("FETCH_HEAD"));
1c7b76be
MV
461 strbuf_getline(&line, fp, '\n');
462 fclose(fp);
463 ptr = strstr(line.buf, "\tnot-for-merge\t");
464 if (ptr)
465 strbuf_remove(&line, ptr-line.buf+1, 13);
466 strbuf_addbuf(msg, &line);
467 strbuf_release(&line);
c9717ee9 468 goto cleanup;
1c7b76be
MV
469 }
470 strbuf_addf(msg, "%s\t\tcommit '%s'\n",
471 sha1_to_hex(remote_head->sha1), remote);
c9717ee9
JH
472cleanup:
473 strbuf_release(&buf);
474 strbuf_release(&bname);
1c7b76be
MV
475}
476
186458b1 477static int git_merge_config(const char *k, const char *v, void *cb)
1c7b76be
MV
478{
479 if (branch && !prefixcmp(k, "branch.") &&
480 !prefixcmp(k + 7, branch) &&
481 !strcmp(k + 7 + strlen(branch), ".mergeoptions")) {
482 const char **argv;
483 int argc;
484 char *buf;
485
486 buf = xstrdup(v);
487 argc = split_cmdline(buf, &argv);
dc4179f9
DM
488 if (argc < 0)
489 die("Bad branch.%s.mergeoptions string", branch);
1c7b76be
MV
490 argv = xrealloc(argv, sizeof(*argv) * (argc + 2));
491 memmove(argv + 1, argv, sizeof(*argv) * (argc + 1));
492 argc++;
37782920 493 parse_options(argc, argv, NULL, builtin_merge_options,
1c7b76be
MV
494 builtin_merge_usage, 0);
495 free(buf);
496 }
497
498 if (!strcmp(k, "merge.diffstat") || !strcmp(k, "merge.stat"))
499 show_diffstat = git_config_bool(k, v);
500 else if (!strcmp(k, "pull.twohead"))
501 return git_config_string(&pull_twohead, k, v);
502 else if (!strcmp(k, "pull.octopus"))
503 return git_config_string(&pull_octopus, k, v);
4393c237
JH
504 else if (!strcmp(k, "merge.log") || !strcmp(k, "merge.summary"))
505 option_log = git_config_bool(k, v);
1c7b76be
MV
506 return git_diff_ui_config(k, v, cb);
507}
508
509static int read_tree_trivial(unsigned char *common, unsigned char *head,
510 unsigned char *one)
511{
512 int i, nr_trees = 0;
513 struct tree *trees[MAX_UNPACK_TREES];
514 struct tree_desc t[MAX_UNPACK_TREES];
515 struct unpack_trees_options opts;
516
517 memset(&opts, 0, sizeof(opts));
518 opts.head_idx = 2;
519 opts.src_index = &the_index;
520 opts.dst_index = &the_index;
521 opts.update = 1;
522 opts.verbose_update = 1;
523 opts.trivial_merges_only = 1;
524 opts.merge = 1;
525 trees[nr_trees] = parse_tree_indirect(common);
526 if (!trees[nr_trees++])
527 return -1;
528 trees[nr_trees] = parse_tree_indirect(head);
529 if (!trees[nr_trees++])
530 return -1;
531 trees[nr_trees] = parse_tree_indirect(one);
532 if (!trees[nr_trees++])
533 return -1;
534 opts.fn = threeway_merge;
535 cache_tree_free(&active_cache_tree);
536 for (i = 0; i < nr_trees; i++) {
537 parse_tree(trees[i]);
538 init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
539 }
540 if (unpack_trees(nr_trees, t, &opts))
541 return -1;
542 return 0;
543}
544
545static void write_tree_trivial(unsigned char *sha1)
546{
547 if (write_cache_as_tree(sha1, 0, NULL))
548 die("git write-tree failed to write a tree");
549}
550
c674d052
CC
551int try_merge_command(const char *strategy, struct commit_list *common,
552 const char *head_arg, struct commit_list *remotes)
1c7b76be
MV
553{
554 const char **args;
8cc5b290 555 int i = 0, x = 0, ret;
1c7b76be 556 struct commit_list *j;
f285a2d7 557 struct strbuf buf = STRBUF_INIT;
3f9083cd
CC
558
559 args = xmalloc((4 + xopts_nr + commit_list_count(common) +
560 commit_list_count(remotes)) * sizeof(char *));
561 strbuf_addf(&buf, "merge-%s", strategy);
562 args[i++] = buf.buf;
563 for (x = 0; x < xopts_nr; x++) {
564 char *s = xmalloc(strlen(xopts[x])+2+1);
565 strcpy(s, "--");
566 strcpy(s+2, xopts[x]);
567 args[i++] = s;
568 }
569 for (j = common; j; j = j->next)
570 args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
571 args[i++] = "--";
572 args[i++] = head_arg;
573 for (j = remotes; j; j = j->next)
574 args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
575 args[i] = NULL;
576 ret = run_command_v_opt(args, RUN_GIT_CMD);
577 strbuf_release(&buf);
578 i = 1;
579 for (x = 0; x < xopts_nr; x++)
580 free((void *)args[i++]);
581 for (j = common; j; j = j->next)
582 free((void *)args[i++]);
583 i += 2;
584 for (j = remotes; j; j = j->next)
585 free((void *)args[i++]);
586 free(args);
587 discard_cache();
588 if (read_cache() < 0)
589 die("failed to read the cache");
590 resolve_undo_clear();
591
592 return ret;
593}
594
595static int try_merge_strategy(const char *strategy, struct commit_list *common,
596 const char *head_arg)
597{
668f26ff
MV
598 int index_fd;
599 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
600
601 index_fd = hold_locked_index(lock, 1);
602 refresh_cache(REFRESH_QUIET);
603 if (active_cache_changed &&
604 (write_cache(index_fd, active_cache, active_nr) ||
605 commit_locked_index(lock)))
606 return error("Unable to write index.");
607 rollback_lock_file(lock);
1c7b76be 608
18668f53 609 if (!strcmp(strategy, "recursive") || !strcmp(strategy, "subtree")) {
3f9083cd 610 int clean, x;
18668f53
MV
611 struct commit *result;
612 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
613 int index_fd;
614 struct commit_list *reversed = NULL;
615 struct merge_options o;
3f9083cd 616 struct commit_list *j;
18668f53
MV
617
618 if (remoteheads->next) {
619 error("Not handling anything other than two heads merge.");
620 return 2;
621 }
622
623 init_merge_options(&o);
624 if (!strcmp(strategy, "subtree"))
85e51b78 625 o.subtree_shift = "";
8cc5b290
AP
626
627 for (x = 0; x < xopts_nr; x++) {
628 if (!strcmp(xopts[x], "ours"))
629 o.recursive_variant = MERGE_RECURSIVE_OURS;
630 else if (!strcmp(xopts[x], "theirs"))
631 o.recursive_variant = MERGE_RECURSIVE_THEIRS;
632 else if (!strcmp(xopts[x], "subtree"))
85e51b78
JH
633 o.subtree_shift = "";
634 else if (!prefixcmp(xopts[x], "subtree="))
635 o.subtree_shift = xopts[x]+8;
8cc5b290
AP
636 else
637 die("Unknown option for merge-recursive: -X%s", xopts[x]);
638 }
18668f53
MV
639
640 o.branch1 = head_arg;
641 o.branch2 = remoteheads->item->util;
642
643 for (j = common; j; j = j->next)
644 commit_list_insert(j->item, &reversed);
645
646 index_fd = hold_locked_index(lock, 1);
647 clean = merge_recursive(&o, lookup_commit(head),
648 remoteheads->item, reversed, &result);
649 if (active_cache_changed &&
650 (write_cache(index_fd, active_cache, active_nr) ||
651 commit_locked_index(lock)))
652 die ("unable to write %s", get_index_file());
42716660 653 rollback_lock_file(lock);
18668f53
MV
654 return clean ? 0 : 1;
655 } else {
3f9083cd 656 return try_merge_command(strategy, common, head_arg, remoteheads);
18668f53 657 }
1c7b76be
MV
658}
659
660static void count_diff_files(struct diff_queue_struct *q,
661 struct diff_options *opt, void *data)
662{
663 int *count = data;
664
665 (*count) += q->nr;
666}
667
668static int count_unmerged_entries(void)
669{
1c7b76be
MV
670 int i, ret = 0;
671
be6ff819
JH
672 for (i = 0; i < active_nr; i++)
673 if (ce_stage(active_cache[i]))
1c7b76be
MV
674 ret++;
675
676 return ret;
677}
678
cac42b26 679int checkout_fast_forward(const unsigned char *head, const unsigned char *remote)
1c7b76be
MV
680{
681 struct tree *trees[MAX_UNPACK_TREES];
682 struct unpack_trees_options opts;
683 struct tree_desc t[MAX_UNPACK_TREES];
684 int i, fd, nr_trees = 0;
685 struct dir_struct dir;
686 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
687
9ca8f607 688 refresh_cache(REFRESH_QUIET);
1c7b76be
MV
689
690 fd = hold_locked_index(lock_file, 1);
691
692 memset(&trees, 0, sizeof(trees));
693 memset(&opts, 0, sizeof(opts));
694 memset(&t, 0, sizeof(t));
5d2299de 695 memset(&dir, 0, sizeof(dir));
7c4c97c0 696 dir.flags |= DIR_SHOW_IGNORED;
1c7b76be
MV
697 dir.exclude_per_dir = ".gitignore";
698 opts.dir = &dir;
699
700 opts.head_idx = 1;
701 opts.src_index = &the_index;
702 opts.dst_index = &the_index;
703 opts.update = 1;
704 opts.verbose_update = 1;
705 opts.merge = 1;
706 opts.fn = twoway_merge;
e6c111b4 707 opts.show_all_errors = 1;
23cbf11b 708 set_porcelain_error_msgs(opts.msgs, "merge");
1c7b76be
MV
709
710 trees[nr_trees] = parse_tree_indirect(head);
711 if (!trees[nr_trees++])
712 return -1;
713 trees[nr_trees] = parse_tree_indirect(remote);
714 if (!trees[nr_trees++])
715 return -1;
716 for (i = 0; i < nr_trees; i++) {
717 parse_tree(trees[i]);
718 init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
719 }
720 if (unpack_trees(nr_trees, t, &opts))
721 return -1;
722 if (write_cache(fd, active_cache, active_nr) ||
723 commit_locked_index(lock_file))
724 die("unable to write new index file");
725 return 0;
726}
727
728static void split_merge_strategies(const char *string, struct strategy **list,
729 int *nr, int *alloc)
730{
731 char *p, *q, *buf;
732
733 if (!string)
734 return;
735
736 buf = xstrdup(string);
737 q = buf;
738 for (;;) {
739 p = strchr(q, ' ');
740 if (!p) {
741 ALLOC_GROW(*list, *nr + 1, *alloc);
742 (*list)[(*nr)++].name = xstrdup(q);
743 free(buf);
744 return;
745 } else {
746 *p = '\0';
747 ALLOC_GROW(*list, *nr + 1, *alloc);
748 (*list)[(*nr)++].name = xstrdup(q);
749 q = ++p;
750 }
751 }
752}
753
754static void add_strategies(const char *string, unsigned attr)
755{
756 struct strategy *list = NULL;
757 int list_alloc = 0, list_nr = 0, i;
758
759 memset(&list, 0, sizeof(list));
760 split_merge_strategies(string, &list, &list_nr, &list_alloc);
1719b5e4
MV
761 if (list) {
762 for (i = 0; i < list_nr; i++)
763 append_strategy(get_strategy(list[i].name));
1c7b76be
MV
764 return;
765 }
766 for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
767 if (all_strategy[i].attr & attr)
768 append_strategy(&all_strategy[i]);
769
770}
771
772static int merge_trivial(void)
773{
774 unsigned char result_tree[20], result_commit[20];
36e40535 775 struct commit_list *parent = xmalloc(sizeof(*parent));
1c7b76be
MV
776
777 write_tree_trivial(result_tree);
778 printf("Wonderful.\n");
446247db 779 parent->item = lookup_commit(head);
36e40535 780 parent->next = xmalloc(sizeof(*parent->next));
446247db
JH
781 parent->next->item = remoteheads->item;
782 parent->next->next = NULL;
ee20a129 783 commit_tree(merge_msg.buf, result_tree, parent, result_commit, NULL);
1c7b76be
MV
784 finish(result_commit, "In-index merge");
785 drop_save();
786 return 0;
787}
788
789static int finish_automerge(struct commit_list *common,
790 unsigned char *result_tree,
791 const char *wt_strategy)
792{
793 struct commit_list *parents = NULL, *j;
794 struct strbuf buf = STRBUF_INIT;
795 unsigned char result_commit[20];
796
797 free_commit_list(common);
798 if (allow_fast_forward) {
799 parents = remoteheads;
800 commit_list_insert(lookup_commit(head), &parents);
801 parents = reduce_heads(parents);
802 } else {
803 struct commit_list **pptr = &parents;
804
805 pptr = &commit_list_insert(lookup_commit(head),
806 pptr)->next;
807 for (j = remoteheads; j; j = j->next)
808 pptr = &commit_list_insert(j->item, pptr)->next;
809 }
810 free_commit_list(remoteheads);
811 strbuf_addch(&merge_msg, '\n');
ee20a129 812 commit_tree(merge_msg.buf, result_tree, parents, result_commit, NULL);
1c7b76be
MV
813 strbuf_addf(&buf, "Merge made by %s.", wt_strategy);
814 finish(result_commit, buf.buf);
815 strbuf_release(&buf);
816 drop_save();
817 return 0;
818}
819
820static int suggest_conflicts(void)
821{
822 FILE *fp;
823 int pos;
824
825 fp = fopen(git_path("MERGE_MSG"), "a");
826 if (!fp)
0721c314
TR
827 die_errno("Could not open '%s' for writing",
828 git_path("MERGE_MSG"));
1c7b76be
MV
829 fprintf(fp, "\nConflicts:\n");
830 for (pos = 0; pos < active_nr; pos++) {
831 struct cache_entry *ce = active_cache[pos];
832
833 if (ce_stage(ce)) {
834 fprintf(fp, "\t%s\n", ce->name);
835 while (pos + 1 < active_nr &&
836 !strcmp(ce->name,
837 active_cache[pos + 1]->name))
838 pos++;
839 }
840 }
841 fclose(fp);
cb6020bb 842 rerere(allow_rerere_auto);
1c7b76be
MV
843 printf("Automatic merge failed; "
844 "fix conflicts and then commit the result.\n");
845 return 1;
846}
847
848static struct commit *is_old_style_invocation(int argc, const char **argv)
849{
850 struct commit *second_token = NULL;
76bf488e 851 if (argc > 2) {
1c7b76be
MV
852 unsigned char second_sha1[20];
853
854 if (get_sha1(argv[1], second_sha1))
855 return NULL;
856 second_token = lookup_commit_reference_gently(second_sha1, 0);
857 if (!second_token)
858 die("'%s' is not a commit", argv[1]);
859 if (hashcmp(second_token->object.sha1, head))
860 return NULL;
861 }
862 return second_token;
863}
864
865static int evaluate_result(void)
866{
867 int cnt = 0;
868 struct rev_info rev;
869
1c7b76be
MV
870 /* Check how many files differ. */
871 init_revisions(&rev, "");
872 setup_revisions(0, NULL, &rev, NULL);
873 rev.diffopt.output_format |=
874 DIFF_FORMAT_CALLBACK;
875 rev.diffopt.format_callback = count_diff_files;
876 rev.diffopt.format_callback_data = &cnt;
877 run_diff_files(&rev, 0);
878
879 /*
880 * Check how many unmerged entries are
881 * there.
882 */
883 cnt += count_unmerged_entries();
884
885 return cnt;
886}
887
888int cmd_merge(int argc, const char **argv, const char *prefix)
889{
890 unsigned char result_tree[20];
f285a2d7 891 struct strbuf buf = STRBUF_INIT;
1c7b76be
MV
892 const char *head_arg;
893 int flag, head_invalid = 0, i;
894 int best_cnt = -1, merge_was_ok = 0, automerge_was_ok = 0;
895 struct commit_list *common = NULL;
896 const char *best_strategy = NULL, *wt_strategy = NULL;
897 struct commit_list **remotes = &remoteheads;
898
d38a30df
MM
899 if (read_cache_unmerged()) {
900 die_resolve_conflict("merge");
901 }
902 if (file_exists(git_path("MERGE_HEAD"))) {
903 /*
904 * There is no unmerged entry, don't advise 'git
905 * add/rm <file>', just 'git commit'.
906 */
907 if (advice_resolve_conflict)
908 die("You have not concluded your merge (MERGE_HEAD exists).\n"
909 "Please, commit your changes before you can merge.");
910 else
911 die("You have not concluded your merge (MERGE_HEAD exists).");
912 }
1c7b76be 913
cfc5789a 914 resolve_undo_clear();
1c7b76be
MV
915 /*
916 * Check if we are _not_ on a detached HEAD, i.e. if there is a
917 * current branch.
918 */
919 branch = resolve_ref("HEAD", head, 0, &flag);
920 if (branch && !prefixcmp(branch, "refs/heads/"))
921 branch += 11;
922 if (is_null_sha1(head))
923 head_invalid = 1;
924
925 git_config(git_merge_config, NULL);
926
927 /* for color.ui */
928 if (diff_use_color_default == -1)
929 diff_use_color_default = git_use_color_default;
930
37782920 931 argc = parse_options(argc, argv, prefix, builtin_merge_options,
1c7b76be 932 builtin_merge_usage, 0);
7f87aff2
TA
933 if (verbosity < 0)
934 show_diffstat = 0;
1c7b76be
MV
935
936 if (squash) {
937 if (!allow_fast_forward)
938 die("You cannot combine --squash with --no-ff.");
939 option_commit = 0;
940 }
941
13474835
BG
942 if (!allow_fast_forward && fast_forward_only)
943 die("You cannot combine --no-ff with --ff-only.");
944
1c7b76be
MV
945 if (!argc)
946 usage_with_options(builtin_merge_usage,
947 builtin_merge_options);
948
949 /*
950 * This could be traditional "merge <msg> HEAD <commit>..." and
951 * the way we can tell it is to see if the second token is HEAD,
952 * but some people might have misused the interface and used a
953 * committish that is the same as HEAD there instead.
954 * Traditional format never would have "-m" so it is an
955 * additional safety measure to check for it.
956 */
1c7b76be
MV
957
958 if (!have_message && is_old_style_invocation(argc, argv)) {
959 strbuf_addstr(&merge_msg, argv[0]);
960 head_arg = argv[1];
961 argv += 2;
962 argc -= 2;
963 } else if (head_invalid) {
964 struct object *remote_head;
965 /*
966 * If the merged head is a valid one there is no reason
967 * to forbid "git merge" into a branch yet to be born.
968 * We do the same for "git pull".
969 */
970 if (argc != 1)
971 die("Can merge only exactly one commit into "
972 "empty head");
4be636f4
PB
973 if (squash)
974 die("Squash commit into empty head not supported yet");
975 if (!allow_fast_forward)
976 die("Non-fast-forward commit does not make sense into "
977 "an empty head");
1c7b76be
MV
978 remote_head = peel_to_type(argv[0], 0, NULL, OBJ_COMMIT);
979 if (!remote_head)
980 die("%s - not something we can merge", argv[0]);
981 update_ref("initial pull", "HEAD", remote_head->sha1, NULL, 0,
982 DIE_ON_ERR);
983 reset_hard(remote_head->sha1, 0);
984 return 0;
985 } else {
97d45bcb 986 struct strbuf merge_names = STRBUF_INIT;
1c7b76be
MV
987
988 /* We are invoked directly as the first-class UI. */
989 head_arg = "HEAD";
990
991 /*
992 * All the rest are the commits being merged;
993 * prepare the standard merge summary message to
994 * be appended to the given message. If remote
995 * is invalid we will die later in the common
996 * codepath so we discard the error in this
997 * loop.
998 */
f0ecac2b
TRC
999 for (i = 0; i < argc; i++)
1000 merge_name(argv[i], &merge_names);
1001
1002 if (have_message && option_log)
1003 fmt_merge_msg_shortlog(&merge_names, &merge_msg);
1004 else if (!have_message)
97d45bcb 1005 fmt_merge_msg(option_log, &merge_names, &merge_msg);
f0ecac2b
TRC
1006
1007
1008 if (!(have_message && !option_log) && merge_msg.len)
1009 strbuf_setlen(&merge_msg, merge_msg.len-1);
1c7b76be
MV
1010 }
1011
1012 if (head_invalid || !argc)
1013 usage_with_options(builtin_merge_usage,
1014 builtin_merge_options);
1015
1016 strbuf_addstr(&buf, "merge");
1017 for (i = 0; i < argc; i++)
1018 strbuf_addf(&buf, " %s", argv[i]);
1019 setenv("GIT_REFLOG_ACTION", buf.buf, 0);
1020 strbuf_reset(&buf);
1021
1022 for (i = 0; i < argc; i++) {
1023 struct object *o;
18668f53 1024 struct commit *commit;
1c7b76be
MV
1025
1026 o = peel_to_type(argv[i], 0, NULL, OBJ_COMMIT);
1027 if (!o)
1028 die("%s - not something we can merge", argv[i]);
18668f53
MV
1029 commit = lookup_commit(o->sha1);
1030 commit->util = (void *)argv[i];
1031 remotes = &commit_list_insert(commit, remotes)->next;
1c7b76be
MV
1032
1033 strbuf_addf(&buf, "GITHEAD_%s", sha1_to_hex(o->sha1));
1034 setenv(buf.buf, argv[i], 1);
1035 strbuf_reset(&buf);
1036 }
1037
1038 if (!use_strategies) {
1039 if (!remoteheads->next)
1040 add_strategies(pull_twohead, DEFAULT_TWOHEAD);
1041 else
1042 add_strategies(pull_octopus, DEFAULT_OCTOPUS);
1043 }
1044
1045 for (i = 0; i < use_strategies_nr; i++) {
1046 if (use_strategies[i]->attr & NO_FAST_FORWARD)
1047 allow_fast_forward = 0;
1048 if (use_strategies[i]->attr & NO_TRIVIAL)
1049 allow_trivial = 0;
1050 }
1051
1052 if (!remoteheads->next)
1053 common = get_merge_bases(lookup_commit(head),
1054 remoteheads->item, 1);
1055 else {
1056 struct commit_list *list = remoteheads;
1057 commit_list_insert(lookup_commit(head), &list);
1058 common = get_octopus_merge_bases(list);
1059 free(list);
1060 }
1061
1062 update_ref("updating ORIG_HEAD", "ORIG_HEAD", head, NULL, 0,
1063 DIE_ON_ERR);
1064
1065 if (!common)
1066 ; /* No common ancestors found. We need a real merge. */
1067 else if (!remoteheads->next && !common->next &&
1068 common->item == remoteheads->item) {
1069 /*
1070 * If head can reach all the merge then we are up to date.
1071 * but first the most common case of merging one remote.
1072 */
1073 finish_up_to_date("Already up-to-date.");
1074 return 0;
1075 } else if (allow_fast_forward && !remoteheads->next &&
1076 !common->next &&
1077 !hashcmp(common->item->object.sha1, head)) {
1078 /* Again the most common case of merging one remote. */
f285a2d7 1079 struct strbuf msg = STRBUF_INIT;
1c7b76be
MV
1080 struct object *o;
1081 char hex[41];
1082
1083 strcpy(hex, find_unique_abbrev(head, DEFAULT_ABBREV));
1084
7f87aff2
TA
1085 if (verbosity >= 0)
1086 printf("Updating %s..%s\n",
1087 hex,
1088 find_unique_abbrev(remoteheads->item->object.sha1,
1089 DEFAULT_ABBREV));
a75d7b54 1090 strbuf_addstr(&msg, "Fast-forward");
1c7b76be
MV
1091 if (have_message)
1092 strbuf_addstr(&msg,
1093 " (no commit created; -m option ignored)");
1094 o = peel_to_type(sha1_to_hex(remoteheads->item->object.sha1),
1095 0, NULL, OBJ_COMMIT);
1096 if (!o)
1097 return 1;
1098
1099 if (checkout_fast_forward(head, remoteheads->item->object.sha1))
1100 return 1;
1101
1102 finish(o->sha1, msg.buf);
1103 drop_save();
1104 return 0;
1105 } else if (!remoteheads->next && common->next)
1106 ;
1107 /*
a75d7b54 1108 * We are not doing octopus and not fast-forward. Need
1c7b76be
MV
1109 * a real merge.
1110 */
1111 else if (!remoteheads->next && !common->next && option_commit) {
1112 /*
a75d7b54 1113 * We are not doing octopus, not fast-forward, and have
1c7b76be
MV
1114 * only one common.
1115 */
1116 refresh_cache(REFRESH_QUIET);
13474835 1117 if (allow_trivial && !fast_forward_only) {
1c7b76be
MV
1118 /* See if it is really trivial. */
1119 git_committer_info(IDENT_ERROR_ON_NO_NAME);
1120 printf("Trying really trivial in-index merge...\n");
1121 if (!read_tree_trivial(common->item->object.sha1,
1122 head, remoteheads->item->object.sha1))
1123 return merge_trivial();
1124 printf("Nope.\n");
1125 }
1126 } else {
1127 /*
1128 * An octopus. If we can reach all the remote we are up
1129 * to date.
1130 */
1131 int up_to_date = 1;
1132 struct commit_list *j;
1133
1134 for (j = remoteheads; j; j = j->next) {
1135 struct commit_list *common_one;
1136
1137 /*
1138 * Here we *have* to calculate the individual
1139 * merge_bases again, otherwise "git merge HEAD^
1140 * HEAD^^" would be missed.
1141 */
1142 common_one = get_merge_bases(lookup_commit(head),
1143 j->item, 1);
1144 if (hashcmp(common_one->item->object.sha1,
1145 j->item->object.sha1)) {
1146 up_to_date = 0;
1147 break;
1148 }
1149 }
1150 if (up_to_date) {
1151 finish_up_to_date("Already up-to-date. Yeeah!");
1152 return 0;
1153 }
1154 }
1155
13474835 1156 if (fast_forward_only)
4d8c3258 1157 die("Not possible to fast-forward, aborting.");
13474835 1158
1c7b76be
MV
1159 /* We are going to make a new commit. */
1160 git_committer_info(IDENT_ERROR_ON_NO_NAME);
1161
1162 /*
1163 * At this point, we need a real merge. No matter what strategy
1164 * we use, it would operate on the index, possibly affecting the
1165 * working tree, and when resolved cleanly, have the desired
1166 * tree in the index -- this means that the index must be in
1167 * sync with the head commit. The strategies are responsible
1168 * to ensure this.
1169 */
1170 if (use_strategies_nr != 1) {
1171 /*
1172 * Stash away the local changes so that we can try more
1173 * than one.
1174 */
1175 save_state();
1176 } else {
1177 memcpy(stash, null_sha1, 20);
1178 }
1179
1180 for (i = 0; i < use_strategies_nr; i++) {
1181 int ret;
1182 if (i) {
1183 printf("Rewinding the tree to pristine...\n");
1184 restore_state();
1185 }
1186 if (use_strategies_nr != 1)
1187 printf("Trying merge strategy %s...\n",
1188 use_strategies[i]->name);
1189 /*
1190 * Remember which strategy left the state in the working
1191 * tree.
1192 */
1193 wt_strategy = use_strategies[i]->name;
1194
1195 ret = try_merge_strategy(use_strategies[i]->name,
1196 common, head_arg);
1197 if (!option_commit && !ret) {
1198 merge_was_ok = 1;
1199 /*
1200 * This is necessary here just to avoid writing
1201 * the tree, but later we will *not* exit with
1202 * status code 1 because merge_was_ok is set.
1203 */
1204 ret = 1;
1205 }
1206
1207 if (ret) {
1208 /*
1209 * The backend exits with 1 when conflicts are
1210 * left to be resolved, with 2 when it does not
1211 * handle the given merge at all.
1212 */
1213 if (ret == 1) {
1214 int cnt = evaluate_result();
1215
1216 if (best_cnt <= 0 || cnt <= best_cnt) {
1217 best_strategy = use_strategies[i]->name;
1218 best_cnt = cnt;
1219 }
1220 }
1221 if (merge_was_ok)
1222 break;
1223 else
1224 continue;
1225 }
1226
1227 /* Automerge succeeded. */
1228 write_tree_trivial(result_tree);
1229 automerge_was_ok = 1;
1230 break;
1231 }
1232
1233 /*
1234 * If we have a resulting tree, that means the strategy module
1235 * auto resolved the merge cleanly.
1236 */
1237 if (automerge_was_ok)
1238 return finish_automerge(common, result_tree, wt_strategy);
1239
1240 /*
1241 * Pick the result from the best strategy and have the user fix
1242 * it up.
1243 */
1244 if (!best_strategy) {
1245 restore_state();
1246 if (use_strategies_nr > 1)
1247 fprintf(stderr,
1248 "No merge strategy handled the merge.\n");
1249 else
1250 fprintf(stderr, "Merge with strategy %s failed.\n",
1251 use_strategies[0]->name);
1252 return 2;
1253 } else if (best_strategy == wt_strategy)
1254 ; /* We already have its result in the working tree. */
1255 else {
1256 printf("Rewinding the tree to pristine...\n");
1257 restore_state();
1258 printf("Using the %s to prepare resolving by hand.\n",
1259 best_strategy);
1260 try_merge_strategy(best_strategy, common, head_arg);
1261 }
1262
1263 if (squash)
1264 finish(NULL, NULL);
1265 else {
1266 int fd;
1267 struct commit_list *j;
1268
1269 for (j = remoteheads; j; j = j->next)
1270 strbuf_addf(&buf, "%s\n",
1271 sha1_to_hex(j->item->object.sha1));
1272 fd = open(git_path("MERGE_HEAD"), O_WRONLY | O_CREAT, 0666);
1273 if (fd < 0)
0721c314
TR
1274 die_errno("Could not open '%s' for writing",
1275 git_path("MERGE_HEAD"));
1c7b76be 1276 if (write_in_full(fd, buf.buf, buf.len) != buf.len)
0721c314 1277 die_errno("Could not write to '%s'", git_path("MERGE_HEAD"));
1c7b76be
MV
1278 close(fd);
1279 strbuf_addch(&merge_msg, '\n');
1280 fd = open(git_path("MERGE_MSG"), O_WRONLY | O_CREAT, 0666);
1281 if (fd < 0)
0721c314
TR
1282 die_errno("Could not open '%s' for writing",
1283 git_path("MERGE_MSG"));
1c7b76be
MV
1284 if (write_in_full(fd, merge_msg.buf, merge_msg.len) !=
1285 merge_msg.len)
0721c314 1286 die_errno("Could not write to '%s'", git_path("MERGE_MSG"));
1c7b76be 1287 close(fd);
cf10f9fd
MV
1288 fd = open(git_path("MERGE_MODE"), O_WRONLY | O_CREAT | O_TRUNC, 0666);
1289 if (fd < 0)
0721c314
TR
1290 die_errno("Could not open '%s' for writing",
1291 git_path("MERGE_MODE"));
cf10f9fd
MV
1292 strbuf_reset(&buf);
1293 if (!allow_fast_forward)
1294 strbuf_addf(&buf, "no-ff");
1295 if (write_in_full(fd, buf.buf, buf.len) != buf.len)
0721c314 1296 die_errno("Could not write to '%s'", git_path("MERGE_MODE"));
cf10f9fd 1297 close(fd);
1c7b76be
MV
1298 }
1299
1300 if (merge_was_ok) {
1301 fprintf(stderr, "Automatic merge went well; "
1302 "stopped before committing as requested\n");
1303 return 0;
1304 } else
1305 return suggest_conflicts();
1306}