checkout: error out when index is unmerged even with -m
[git] / builtin-commit.c
1 /*
2  * Builtin "git commit"
3  *
4  * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>
5  * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
6  */
7
8 #include "cache.h"
9 #include "cache-tree.h"
10 #include "dir.h"
11 #include "builtin.h"
12 #include "diff.h"
13 #include "diffcore.h"
14 #include "commit.h"
15 #include "revision.h"
16 #include "wt-status.h"
17 #include "run-command.h"
18 #include "refs.h"
19 #include "log-tree.h"
20 #include "strbuf.h"
21 #include "utf8.h"
22 #include "parse-options.h"
23 #include "path-list.h"
24 #include "unpack-trees.h"
25
26 static const char * const builtin_commit_usage[] = {
27         "git-commit [options] [--] <filepattern>...",
28         NULL
29 };
30
31 static const char * const builtin_status_usage[] = {
32         "git-status [options] [--] <filepattern>...",
33         NULL
34 };
35
36 static unsigned char head_sha1[20], merge_head_sha1[20];
37 static char *use_message_buffer;
38 static const char commit_editmsg[] = "COMMIT_EDITMSG";
39 static struct lock_file index_lock; /* real index */
40 static struct lock_file false_lock; /* used only for partial commits */
41 static enum {
42         COMMIT_AS_IS = 1,
43         COMMIT_NORMAL,
44         COMMIT_PARTIAL,
45 } commit_style;
46
47 static char *logfile, *force_author, *template_file;
48 static char *edit_message, *use_message;
49 static int all, edit_flag, also, interactive, only, amend, signoff;
50 static int quiet, verbose, untracked_files, no_verify, allow_empty;
51 /*
52  * The default commit message cleanup mode will remove the lines
53  * beginning with # (shell comments) and leading and trailing
54  * whitespaces (empty lines or containing only whitespaces)
55  * if editor is used, and only the whitespaces if the message
56  * is specified explicitly.
57  */
58 static enum {
59         CLEANUP_SPACE,
60         CLEANUP_NONE,
61         CLEANUP_ALL,
62 } cleanup_mode;
63 static char *cleanup_arg;
64
65 static int use_editor = 1, initial_commit, in_merge;
66 const char *only_include_assumed;
67 struct strbuf message;
68
69 static int opt_parse_m(const struct option *opt, const char *arg, int unset)
70 {
71         struct strbuf *buf = opt->value;
72         if (unset)
73                 strbuf_setlen(buf, 0);
74         else {
75                 strbuf_addstr(buf, arg);
76                 strbuf_addch(buf, '\n');
77                 strbuf_addch(buf, '\n');
78         }
79         return 0;
80 }
81
82 static struct option builtin_commit_options[] = {
83         OPT__QUIET(&quiet),
84         OPT__VERBOSE(&verbose),
85         OPT_GROUP("Commit message options"),
86
87         OPT_STRING('F', "file", &logfile, "FILE", "read log from file"),
88         OPT_STRING(0, "author", &force_author, "AUTHOR", "override author for commit"),
89         OPT_CALLBACK('m', "message", &message, "MESSAGE", "specify commit message", opt_parse_m),
90         OPT_STRING('c', "reedit-message", &edit_message, "COMMIT", "reuse and edit message from specified commit "),
91         OPT_STRING('C', "reuse-message", &use_message, "COMMIT", "reuse message from specified commit"),
92         OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by: header"),
93         OPT_STRING('t', "template", &template_file, "FILE", "use specified template file"),
94         OPT_BOOLEAN('e', "edit", &edit_flag, "force edit of commit"),
95
96         OPT_GROUP("Commit contents options"),
97         OPT_BOOLEAN('a', "all", &all, "commit all changed files"),
98         OPT_BOOLEAN('i', "include", &also, "add specified files to index for commit"),
99         OPT_BOOLEAN(0, "interactive", &interactive, "interactively add files"),
100         OPT_BOOLEAN('o', "only", &only, ""),
101         OPT_BOOLEAN('n', "no-verify", &no_verify, "bypass pre-commit hook"),
102         OPT_BOOLEAN(0, "amend", &amend, "amend previous commit"),
103         OPT_BOOLEAN(0, "untracked-files", &untracked_files, "show all untracked files"),
104         OPT_BOOLEAN(0, "allow-empty", &allow_empty, "ok to record an empty change"),
105         OPT_STRING(0, "cleanup", &cleanup_arg, "default", "how to strip spaces and #comments from message"),
106
107         OPT_END()
108 };
109
110 static void rollback_index_files(void)
111 {
112         switch (commit_style) {
113         case COMMIT_AS_IS:
114                 break; /* nothing to do */
115         case COMMIT_NORMAL:
116                 rollback_lock_file(&index_lock);
117                 break;
118         case COMMIT_PARTIAL:
119                 rollback_lock_file(&index_lock);
120                 rollback_lock_file(&false_lock);
121                 break;
122         }
123 }
124
125 static void commit_index_files(void)
126 {
127         switch (commit_style) {
128         case COMMIT_AS_IS:
129                 break; /* nothing to do */
130         case COMMIT_NORMAL:
131                 commit_lock_file(&index_lock);
132                 break;
133         case COMMIT_PARTIAL:
134                 commit_lock_file(&index_lock);
135                 rollback_lock_file(&false_lock);
136                 break;
137         }
138 }
139
140 /*
141  * Take a union of paths in the index and the named tree (typically, "HEAD"),
142  * and return the paths that match the given pattern in list.
143  */
144 static int list_paths(struct path_list *list, const char *with_tree,
145                       const char *prefix, const char **pattern)
146 {
147         int i;
148         char *m;
149
150         for (i = 0; pattern[i]; i++)
151                 ;
152         m = xcalloc(1, i);
153
154         if (with_tree)
155                 overlay_tree_on_cache(with_tree, prefix);
156
157         for (i = 0; i < active_nr; i++) {
158                 struct cache_entry *ce = active_cache[i];
159                 if (ce->ce_flags & CE_UPDATE)
160                         continue;
161                 if (!pathspec_match(pattern, m, ce->name, 0))
162                         continue;
163                 path_list_insert(ce->name, list);
164         }
165
166         return report_path_error(m, pattern, prefix ? strlen(prefix) : 0);
167 }
168
169 static void add_remove_files(struct path_list *list)
170 {
171         int i;
172         for (i = 0; i < list->nr; i++) {
173                 struct path_list_item *p = &(list->items[i]);
174                 if (file_exists(p->path))
175                         add_file_to_cache(p->path, 0);
176                 else
177                         remove_file_from_cache(p->path);
178         }
179 }
180
181 static void create_base_index(void)
182 {
183         struct tree *tree;
184         struct unpack_trees_options opts;
185         struct tree_desc t;
186
187         if (initial_commit) {
188                 discard_cache();
189                 return;
190         }
191
192         memset(&opts, 0, sizeof(opts));
193         opts.head_idx = 1;
194         opts.index_only = 1;
195         opts.merge = 1;
196
197         opts.fn = oneway_merge;
198         tree = parse_tree_indirect(head_sha1);
199         if (!tree)
200                 die("failed to unpack HEAD tree object");
201         parse_tree(tree);
202         init_tree_desc(&t, tree->buffer, tree->size);
203         if (unpack_trees(1, &t, &opts))
204                 exit(128); /* We've already reported the error, finish dying */
205 }
206
207 static char *prepare_index(int argc, const char **argv, const char *prefix)
208 {
209         int fd;
210         struct path_list partial;
211         const char **pathspec = NULL;
212
213         if (interactive) {
214                 interactive_add(argc, argv, prefix);
215                 commit_style = COMMIT_AS_IS;
216                 return get_index_file();
217         }
218
219         if (read_cache() < 0)
220                 die("index file corrupt");
221
222         if (*argv)
223                 pathspec = get_pathspec(prefix, argv);
224
225         /*
226          * Non partial, non as-is commit.
227          *
228          * (1) get the real index;
229          * (2) update the_index as necessary;
230          * (3) write the_index out to the real index (still locked);
231          * (4) return the name of the locked index file.
232          *
233          * The caller should run hooks on the locked real index, and
234          * (A) if all goes well, commit the real index;
235          * (B) on failure, rollback the real index.
236          */
237         if (all || (also && pathspec && *pathspec)) {
238                 int fd = hold_locked_index(&index_lock, 1);
239                 add_files_to_cache(0, also ? prefix : NULL, pathspec);
240                 refresh_cache(REFRESH_QUIET);
241                 if (write_cache(fd, active_cache, active_nr) ||
242                     close_lock_file(&index_lock))
243                         die("unable to write new_index file");
244                 commit_style = COMMIT_NORMAL;
245                 return index_lock.filename;
246         }
247
248         /*
249          * As-is commit.
250          *
251          * (1) return the name of the real index file.
252          *
253          * The caller should run hooks on the real index, and run
254          * hooks on the real index, and create commit from the_index.
255          * We still need to refresh the index here.
256          */
257         if (!pathspec || !*pathspec) {
258                 fd = hold_locked_index(&index_lock, 1);
259                 refresh_cache(REFRESH_QUIET);
260                 if (write_cache(fd, active_cache, active_nr) ||
261                     commit_locked_index(&index_lock))
262                         die("unable to write new_index file");
263                 commit_style = COMMIT_AS_IS;
264                 return get_index_file();
265         }
266
267         /*
268          * A partial commit.
269          *
270          * (0) find the set of affected paths;
271          * (1) get lock on the real index file;
272          * (2) update the_index with the given paths;
273          * (3) write the_index out to the real index (still locked);
274          * (4) get lock on the false index file;
275          * (5) reset the_index from HEAD;
276          * (6) update the_index the same way as (2);
277          * (7) write the_index out to the false index file;
278          * (8) return the name of the false index file (still locked);
279          *
280          * The caller should run hooks on the locked false index, and
281          * create commit from it.  Then
282          * (A) if all goes well, commit the real index;
283          * (B) on failure, rollback the real index;
284          * In either case, rollback the false index.
285          */
286         commit_style = COMMIT_PARTIAL;
287
288         if (file_exists(git_path("MERGE_HEAD")))
289                 die("cannot do a partial commit during a merge.");
290
291         memset(&partial, 0, sizeof(partial));
292         partial.strdup_paths = 1;
293         if (list_paths(&partial, initial_commit ? NULL : "HEAD", prefix, pathspec))
294                 exit(1);
295
296         discard_cache();
297         if (read_cache() < 0)
298                 die("cannot read the index");
299
300         fd = hold_locked_index(&index_lock, 1);
301         add_remove_files(&partial);
302         refresh_cache(REFRESH_QUIET);
303         if (write_cache(fd, active_cache, active_nr) ||
304             close_lock_file(&index_lock))
305                 die("unable to write new_index file");
306
307         fd = hold_lock_file_for_update(&false_lock,
308                                        git_path("next-index-%d", getpid()), 1);
309
310         create_base_index();
311         add_remove_files(&partial);
312         refresh_cache(REFRESH_QUIET);
313
314         if (write_cache(fd, active_cache, active_nr) ||
315             close_lock_file(&false_lock))
316                 die("unable to write temporary index file");
317         return false_lock.filename;
318 }
319
320 static int run_status(FILE *fp, const char *index_file, const char *prefix, int nowarn)
321 {
322         struct wt_status s;
323
324         wt_status_prepare(&s);
325         if (wt_status_relative_paths)
326                 s.prefix = prefix;
327
328         if (amend) {
329                 s.amend = 1;
330                 s.reference = "HEAD^1";
331         }
332         s.verbose = verbose;
333         s.untracked = untracked_files;
334         s.index_file = index_file;
335         s.fp = fp;
336         s.nowarn = nowarn;
337
338         wt_status_print(&s);
339
340         return s.commitable;
341 }
342
343 static const char sign_off_header[] = "Signed-off-by: ";
344
345 static int prepare_log_message(const char *index_file, const char *prefix)
346 {
347         struct stat statbuf;
348         int commitable, saved_color_setting;
349         struct strbuf sb;
350         char *buffer;
351         FILE *fp;
352
353         strbuf_init(&sb, 0);
354         if (message.len) {
355                 strbuf_addbuf(&sb, &message);
356         } else if (logfile && !strcmp(logfile, "-")) {
357                 if (isatty(0))
358                         fprintf(stderr, "(reading log message from standard input)\n");
359                 if (strbuf_read(&sb, 0, 0) < 0)
360                         die("could not read log from standard input");
361         } else if (logfile) {
362                 if (strbuf_read_file(&sb, logfile, 0) < 0)
363                         die("could not read log file '%s': %s",
364                             logfile, strerror(errno));
365         } else if (use_message) {
366                 buffer = strstr(use_message_buffer, "\n\n");
367                 if (!buffer || buffer[2] == '\0')
368                         die("commit has empty message");
369                 strbuf_add(&sb, buffer + 2, strlen(buffer + 2));
370         } else if (!stat(git_path("MERGE_MSG"), &statbuf)) {
371                 if (strbuf_read_file(&sb, git_path("MERGE_MSG"), 0) < 0)
372                         die("could not read MERGE_MSG: %s", strerror(errno));
373         } else if (!stat(git_path("SQUASH_MSG"), &statbuf)) {
374                 if (strbuf_read_file(&sb, git_path("SQUASH_MSG"), 0) < 0)
375                         die("could not read SQUASH_MSG: %s", strerror(errno));
376         } else if (template_file && !stat(template_file, &statbuf)) {
377                 if (strbuf_read_file(&sb, template_file, 0) < 0)
378                         die("could not read %s: %s",
379                             template_file, strerror(errno));
380         }
381
382         fp = fopen(git_path(commit_editmsg), "w");
383         if (fp == NULL)
384                 die("could not open %s", git_path(commit_editmsg));
385
386         if (cleanup_mode != CLEANUP_NONE)
387                 stripspace(&sb, 0);
388
389         if (signoff) {
390                 struct strbuf sob;
391                 int i;
392
393                 strbuf_init(&sob, 0);
394                 strbuf_addstr(&sob, sign_off_header);
395                 strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
396                                              getenv("GIT_COMMITTER_EMAIL")));
397                 strbuf_addch(&sob, '\n');
398                 for (i = sb.len - 1; i > 0 && sb.buf[i - 1] != '\n'; i--)
399                         ; /* do nothing */
400                 if (prefixcmp(sb.buf + i, sob.buf)) {
401                         if (prefixcmp(sb.buf + i, sign_off_header))
402                                 strbuf_addch(&sb, '\n');
403                         strbuf_addbuf(&sb, &sob);
404                 }
405                 strbuf_release(&sob);
406         }
407
408         if (fwrite(sb.buf, 1, sb.len, fp) < sb.len)
409                 die("could not write commit template: %s", strerror(errno));
410
411         strbuf_release(&sb);
412
413         if (!use_editor) {
414                 struct rev_info rev;
415                 unsigned char sha1[20];
416                 const char *parent = "HEAD";
417
418                 fclose(fp);
419
420                 if (!active_nr && read_cache() < 0)
421                         die("Cannot read index");
422
423                 if (amend)
424                         parent = "HEAD^1";
425
426                 if (get_sha1(parent, sha1))
427                         return !!active_nr;
428
429                 init_revisions(&rev, "");
430                 rev.abbrev = 0;
431                 setup_revisions(0, NULL, &rev, parent);
432                 DIFF_OPT_SET(&rev.diffopt, QUIET);
433                 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
434                 run_diff_index(&rev, 1 /* cached */);
435
436                 return !!DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES);
437         }
438
439         if (in_merge)
440                 fprintf(fp,
441                         "#\n"
442                         "# It looks like you may be committing a MERGE.\n"
443                         "# If this is not correct, please remove the file\n"
444                         "#      %s\n"
445                         "# and try again.\n"
446                         "#\n",
447                         git_path("MERGE_HEAD"));
448
449         fprintf(fp,
450                 "\n"
451                 "# Please enter the commit message for your changes.\n"
452                 "# (Comment lines starting with '#' will ");
453         if (cleanup_mode == CLEANUP_ALL)
454                 fprintf(fp, "not be included)\n");
455         else /* CLEANUP_SPACE, that is. */
456                 fprintf(fp, "be kept.\n"
457                         "# You can remove them yourself if you want to)\n");
458         if (only_include_assumed)
459                 fprintf(fp, "# %s\n", only_include_assumed);
460
461         saved_color_setting = wt_status_use_color;
462         wt_status_use_color = 0;
463         commitable = run_status(fp, index_file, prefix, 1);
464         wt_status_use_color = saved_color_setting;
465
466         fclose(fp);
467
468         return commitable;
469 }
470
471 /*
472  * Find out if the message starting at position 'start' in the strbuf
473  * contains only whitespace and Signed-off-by lines.
474  */
475 static int message_is_empty(struct strbuf *sb, int start)
476 {
477         struct strbuf tmpl;
478         const char *nl;
479         int eol, i;
480
481         if (cleanup_mode == CLEANUP_NONE && sb->len)
482                 return 0;
483
484         /* See if the template is just a prefix of the message. */
485         strbuf_init(&tmpl, 0);
486         if (template_file && strbuf_read_file(&tmpl, template_file, 0) > 0) {
487                 stripspace(&tmpl, cleanup_mode == CLEANUP_ALL);
488                 if (start + tmpl.len <= sb->len &&
489                     memcmp(tmpl.buf, sb->buf + start, tmpl.len) == 0)
490                         start += tmpl.len;
491         }
492         strbuf_release(&tmpl);
493
494         /* Check if the rest is just whitespace and Signed-of-by's. */
495         for (i = start; i < sb->len; i++) {
496                 nl = memchr(sb->buf + i, '\n', sb->len - i);
497                 if (nl)
498                         eol = nl - sb->buf;
499                 else
500                         eol = sb->len;
501
502                 if (strlen(sign_off_header) <= eol - i &&
503                     !prefixcmp(sb->buf + i, sign_off_header)) {
504                         i = eol;
505                         continue;
506                 }
507                 while (i < eol)
508                         if (!isspace(sb->buf[i++]))
509                                 return 0;
510         }
511
512         return 1;
513 }
514
515 static void determine_author_info(struct strbuf *sb)
516 {
517         char *name, *email, *date;
518
519         name = getenv("GIT_AUTHOR_NAME");
520         email = getenv("GIT_AUTHOR_EMAIL");
521         date = getenv("GIT_AUTHOR_DATE");
522
523         if (use_message) {
524                 const char *a, *lb, *rb, *eol;
525
526                 a = strstr(use_message_buffer, "\nauthor ");
527                 if (!a)
528                         die("invalid commit: %s", use_message);
529
530                 lb = strstr(a + 8, " <");
531                 rb = strstr(a + 8, "> ");
532                 eol = strchr(a + 8, '\n');
533                 if (!lb || !rb || !eol)
534                         die("invalid commit: %s", use_message);
535
536                 name = xstrndup(a + 8, lb - (a + 8));
537                 email = xstrndup(lb + 2, rb - (lb + 2));
538                 date = xstrndup(rb + 2, eol - (rb + 2));
539         }
540
541         if (force_author) {
542                 const char *lb = strstr(force_author, " <");
543                 const char *rb = strchr(force_author, '>');
544
545                 if (!lb || !rb)
546                         die("malformed --author parameter");
547                 name = xstrndup(force_author, lb - force_author);
548                 email = xstrndup(lb + 2, rb - (lb + 2));
549         }
550
551         strbuf_addf(sb, "author %s\n", fmt_ident(name, email, date, IDENT_ERROR_ON_NO_NAME));
552 }
553
554 static int parse_and_validate_options(int argc, const char *argv[],
555                                       const char * const usage[])
556 {
557         int f = 0;
558
559         argc = parse_options(argc, argv, builtin_commit_options, usage, 0);
560
561         if (logfile || message.len || use_message)
562                 use_editor = 0;
563         if (edit_flag)
564                 use_editor = 1;
565
566         if (get_sha1("HEAD", head_sha1))
567                 initial_commit = 1;
568
569         if (!get_sha1("MERGE_HEAD", merge_head_sha1))
570                 in_merge = 1;
571
572         /* Sanity check options */
573         if (amend && initial_commit)
574                 die("You have nothing to amend.");
575         if (amend && in_merge)
576                 die("You are in the middle of a merge -- cannot amend.");
577
578         if (use_message)
579                 f++;
580         if (edit_message)
581                 f++;
582         if (logfile)
583                 f++;
584         if (f > 1)
585                 die("Only one of -c/-C/-F can be used.");
586         if (message.len && f > 0)
587                 die("Option -m cannot be combined with -c/-C/-F.");
588         if (edit_message)
589                 use_message = edit_message;
590         if (amend && !use_message)
591                 use_message = "HEAD";
592         if (use_message) {
593                 unsigned char sha1[20];
594                 static char utf8[] = "UTF-8";
595                 const char *out_enc;
596                 char *enc, *end;
597                 struct commit *commit;
598
599                 if (get_sha1(use_message, sha1))
600                         die("could not lookup commit %s", use_message);
601                 commit = lookup_commit(sha1);
602                 if (!commit || parse_commit(commit))
603                         die("could not parse commit %s", use_message);
604
605                 enc = strstr(commit->buffer, "\nencoding");
606                 if (enc) {
607                         end = strchr(enc + 10, '\n');
608                         enc = xstrndup(enc + 10, end - (enc + 10));
609                 } else {
610                         enc = utf8;
611                 }
612                 out_enc = git_commit_encoding ? git_commit_encoding : utf8;
613
614                 if (strcmp(out_enc, enc))
615                         use_message_buffer =
616                                 reencode_string(commit->buffer, out_enc, enc);
617
618                 /*
619                  * If we failed to reencode the buffer, just copy it
620                  * byte for byte so the user can try to fix it up.
621                  * This also handles the case where input and output
622                  * encodings are identical.
623                  */
624                 if (use_message_buffer == NULL)
625                         use_message_buffer = xstrdup(commit->buffer);
626                 if (enc != utf8)
627                         free(enc);
628         }
629
630         if (!!also + !!only + !!all + !!interactive > 1)
631                 die("Only one of --include/--only/--all/--interactive can be used.");
632         if (argc == 0 && (also || (only && !amend)))
633                 die("No paths with --include/--only does not make sense.");
634         if (argc == 0 && only && amend)
635                 only_include_assumed = "Clever... amending the last one with dirty index.";
636         if (argc > 0 && !also && !only) {
637                 only_include_assumed = "Explicit paths specified without -i nor -o; assuming --only paths...";
638                 also = 0;
639         }
640         if (!cleanup_arg || !strcmp(cleanup_arg, "default"))
641                 cleanup_mode = use_editor ? CLEANUP_ALL : CLEANUP_SPACE;
642         else if (!strcmp(cleanup_arg, "verbatim"))
643                 cleanup_mode = CLEANUP_NONE;
644         else if (!strcmp(cleanup_arg, "whitespace"))
645                 cleanup_mode = CLEANUP_SPACE;
646         else if (!strcmp(cleanup_arg, "strip"))
647                 cleanup_mode = CLEANUP_ALL;
648         else
649                 die("Invalid cleanup mode %s", cleanup_arg);
650
651         if (all && argc > 0)
652                 die("Paths with -a does not make sense.");
653         else if (interactive && argc > 0)
654                 die("Paths with --interactive does not make sense.");
655
656         return argc;
657 }
658
659 int cmd_status(int argc, const char **argv, const char *prefix)
660 {
661         const char *index_file;
662         int commitable;
663
664         git_config(git_status_config);
665
666         argc = parse_and_validate_options(argc, argv, builtin_status_usage);
667
668         index_file = prepare_index(argc, argv, prefix);
669
670         commitable = run_status(stdout, index_file, prefix, 0);
671
672         rollback_index_files();
673
674         return commitable ? 0 : 1;
675 }
676
677 static int run_hook(const char *index_file, const char *name, const char *arg)
678 {
679         struct child_process hook;
680         const char *argv[3], *env[2];
681         char index[PATH_MAX];
682
683         argv[0] = git_path("hooks/%s", name);
684         argv[1] = arg;
685         argv[2] = NULL;
686         snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
687         env[0] = index;
688         env[1] = NULL;
689
690         if (access(argv[0], X_OK) < 0)
691                 return 0;
692
693         memset(&hook, 0, sizeof(hook));
694         hook.argv = argv;
695         hook.no_stdin = 1;
696         hook.stdout_to_stderr = 1;
697         hook.env = env;
698
699         return run_command(&hook);
700 }
701
702 static void print_summary(const char *prefix, const unsigned char *sha1)
703 {
704         struct rev_info rev;
705         struct commit *commit;
706
707         commit = lookup_commit(sha1);
708         if (!commit)
709                 die("couldn't look up newly created commit");
710         if (!commit || parse_commit(commit))
711                 die("could not parse newly created commit");
712
713         init_revisions(&rev, prefix);
714         setup_revisions(0, NULL, &rev, NULL);
715
716         rev.abbrev = 0;
717         rev.diff = 1;
718         rev.diffopt.output_format =
719                 DIFF_FORMAT_SHORTSTAT | DIFF_FORMAT_SUMMARY;
720
721         rev.verbose_header = 1;
722         rev.show_root_diff = 1;
723         rev.commit_format = get_commit_format("format:%h: %s");
724         rev.always_show_header = 0;
725         rev.diffopt.detect_rename = 1;
726         rev.diffopt.rename_limit = 100;
727         rev.diffopt.break_opt = 0;
728         diff_setup_done(&rev.diffopt);
729
730         printf("Created %scommit ", initial_commit ? "initial " : "");
731
732         if (!log_tree_commit(&rev, commit)) {
733                 struct strbuf buf = STRBUF_INIT;
734                 format_commit_message(commit, "%h: %s", &buf);
735                 printf("%s\n", buf.buf);
736                 strbuf_release(&buf);
737         }
738 }
739
740 int git_commit_config(const char *k, const char *v)
741 {
742         if (!strcmp(k, "commit.template")) {
743                 template_file = xstrdup(v);
744                 return 0;
745         }
746
747         return git_status_config(k, v);
748 }
749
750 static int is_a_merge(const unsigned char *sha1)
751 {
752         struct commit *commit = lookup_commit(sha1);
753         if (!commit || parse_commit(commit))
754                 die("could not parse HEAD commit");
755         return !!(commit->parents && commit->parents->next);
756 }
757
758 static const char commit_utf8_warn[] =
759 "Warning: commit message does not conform to UTF-8.\n"
760 "You may want to amend it after fixing the message, or set the config\n"
761 "variable i18n.commitencoding to the encoding your project uses.\n";
762
763 static void add_parent(struct strbuf *sb, const unsigned char *sha1)
764 {
765         struct object *obj = parse_object(sha1);
766         const char *parent = sha1_to_hex(sha1);
767         if (!obj)
768                 die("Unable to find commit parent %s", parent);
769         if (obj->type != OBJ_COMMIT)
770                 die("Parent %s isn't a proper commit", parent);
771         strbuf_addf(sb, "parent %s\n", parent);
772 }
773
774 int cmd_commit(int argc, const char **argv, const char *prefix)
775 {
776         int header_len;
777         struct strbuf sb;
778         const char *index_file, *reflog_msg;
779         char *nl, *p;
780         unsigned char commit_sha1[20];
781         struct ref_lock *ref_lock;
782
783         git_config(git_commit_config);
784
785         argc = parse_and_validate_options(argc, argv, builtin_commit_usage);
786
787         index_file = prepare_index(argc, argv, prefix);
788
789         if (!no_verify && run_hook(index_file, "pre-commit", NULL)) {
790                 rollback_index_files();
791                 return 1;
792         }
793
794         if (!prepare_log_message(index_file, prefix) && !in_merge &&
795             !allow_empty && !(amend && is_a_merge(head_sha1))) {
796                 run_status(stdout, index_file, prefix, 0);
797                 rollback_index_files();
798                 unlink(commit_editmsg);
799                 return 1;
800         }
801
802         /*
803          * Re-read the index as pre-commit hook could have updated it,
804          * and write it out as a tree.
805          */
806         discard_cache();
807         read_cache_from(index_file);
808         if (!active_cache_tree)
809                 active_cache_tree = cache_tree();
810         if (cache_tree_update(active_cache_tree,
811                               active_cache, active_nr, 0, 0) < 0) {
812                 rollback_index_files();
813                 die("Error building trees");
814         }
815
816         /*
817          * The commit object
818          */
819         strbuf_init(&sb, 0);
820         strbuf_addf(&sb, "tree %s\n",
821                     sha1_to_hex(active_cache_tree->sha1));
822
823         /* Determine parents */
824         if (initial_commit) {
825                 reflog_msg = "commit (initial)";
826         } else if (amend) {
827                 struct commit_list *c;
828                 struct commit *commit;
829
830                 reflog_msg = "commit (amend)";
831                 commit = lookup_commit(head_sha1);
832                 if (!commit || parse_commit(commit))
833                         die("could not parse HEAD commit");
834
835                 for (c = commit->parents; c; c = c->next)
836                         add_parent(&sb, c->item->object.sha1);
837         } else if (in_merge) {
838                 struct strbuf m;
839                 FILE *fp;
840
841                 reflog_msg = "commit (merge)";
842                 add_parent(&sb, head_sha1);
843                 strbuf_init(&m, 0);
844                 fp = fopen(git_path("MERGE_HEAD"), "r");
845                 if (fp == NULL)
846                         die("could not open %s for reading: %s",
847                             git_path("MERGE_HEAD"), strerror(errno));
848                 while (strbuf_getline(&m, fp, '\n') != EOF) {
849                         unsigned char sha1[20];
850                         if (get_sha1_hex(m.buf, sha1) < 0)
851                                 die("Corrupt MERGE_HEAD file (%s)", m.buf);
852                         add_parent(&sb, sha1);
853                 }
854                 fclose(fp);
855                 strbuf_release(&m);
856         } else {
857                 reflog_msg = "commit";
858                 strbuf_addf(&sb, "parent %s\n", sha1_to_hex(head_sha1));
859         }
860
861         determine_author_info(&sb);
862         strbuf_addf(&sb, "committer %s\n", git_committer_info(IDENT_ERROR_ON_NO_NAME));
863         if (!is_encoding_utf8(git_commit_encoding))
864                 strbuf_addf(&sb, "encoding %s\n", git_commit_encoding);
865         strbuf_addch(&sb, '\n');
866
867         /* Get the commit message and validate it */
868         header_len = sb.len;
869         if (use_editor) {
870                 char index[PATH_MAX];
871                 const char *env[2] = { index, NULL };
872                 snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
873                 launch_editor(git_path(commit_editmsg), NULL, env);
874         }
875         if (!no_verify &&
876             run_hook(index_file, "commit-msg", git_path(commit_editmsg))) {
877                 rollback_index_files();
878                 exit(1);
879         }
880         if (strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0) {
881                 rollback_index_files();
882                 die("could not read commit message");
883         }
884
885         /* Truncate the message just before the diff, if any. */
886         p = strstr(sb.buf, "\ndiff --git a/");
887         if (p != NULL)
888                 strbuf_setlen(&sb, p - sb.buf + 1);
889
890         if (cleanup_mode != CLEANUP_NONE)
891                 stripspace(&sb, cleanup_mode == CLEANUP_ALL);
892         if (sb.len < header_len || message_is_empty(&sb, header_len)) {
893                 rollback_index_files();
894                 die("no commit message?  aborting commit.");
895         }
896         strbuf_addch(&sb, '\0');
897         if (is_encoding_utf8(git_commit_encoding) && !is_utf8(sb.buf))
898                 fprintf(stderr, commit_utf8_warn);
899
900         if (write_sha1_file(sb.buf, sb.len - 1, commit_type, commit_sha1)) {
901                 rollback_index_files();
902                 die("failed to write commit object");
903         }
904
905         ref_lock = lock_any_ref_for_update("HEAD",
906                                            initial_commit ? NULL : head_sha1,
907                                            0);
908
909         nl = strchr(sb.buf + header_len, '\n');
910         if (nl)
911                 strbuf_setlen(&sb, nl + 1 - sb.buf);
912         else
913                 strbuf_addch(&sb, '\n');
914         strbuf_remove(&sb, 0, header_len);
915         strbuf_insert(&sb, 0, reflog_msg, strlen(reflog_msg));
916         strbuf_insert(&sb, strlen(reflog_msg), ": ", 2);
917
918         if (!ref_lock) {
919                 rollback_index_files();
920                 die("cannot lock HEAD ref");
921         }
922         if (write_ref_sha1(ref_lock, commit_sha1, sb.buf) < 0) {
923                 rollback_index_files();
924                 die("cannot update HEAD ref");
925         }
926
927         unlink(git_path("MERGE_HEAD"));
928         unlink(git_path("MERGE_MSG"));
929
930         commit_index_files();
931
932         rerere();
933         run_hook(get_index_file(), "post-commit", NULL);
934         if (!quiet)
935                 print_summary(prefix, commit_sha1);
936
937         return 0;
938 }