Merge branch 'jl/submodule-status-failure-report'
[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 "color.h"
11 #include "dir.h"
12 #include "builtin.h"
13 #include "diff.h"
14 #include "diffcore.h"
15 #include "commit.h"
16 #include "revision.h"
17 #include "wt-status.h"
18 #include "run-command.h"
19 #include "refs.h"
20 #include "log-tree.h"
21 #include "strbuf.h"
22 #include "utf8.h"
23 #include "parse-options.h"
24 #include "string-list.h"
25 #include "rerere.h"
26 #include "unpack-trees.h"
27 #include "quote.h"
28 #include "submodule.h"
29
30 static const char * const builtin_commit_usage[] = {
31         "git commit [options] [--] <filepattern>...",
32         NULL
33 };
34
35 static const char * const builtin_status_usage[] = {
36         "git status [options] [--] <filepattern>...",
37         NULL
38 };
39
40 static const char implicit_ident_advice[] =
41 N_("Your name and email address were configured automatically based\n"
42 "on your username and hostname. Please check that they are accurate.\n"
43 "You can suppress this message by setting them explicitly:\n"
44 "\n"
45 "    git config --global user.name \"Your Name\"\n"
46 "    git config --global user.email you@example.com\n"
47 "\n"
48 "After doing this, you may fix the identity used for this commit with:\n"
49 "\n"
50 "    git commit --amend --reset-author\n");
51
52 static const char empty_amend_advice[] =
53 N_("You asked to amend the most recent commit, but doing so would make\n"
54 "it empty. You can repeat your command with --allow-empty, or you can\n"
55 "remove the commit entirely with \"git reset HEAD^\".\n");
56
57 static const char empty_cherry_pick_advice[] =
58 N_("The previous cherry-pick is now empty, possibly due to conflict resolution.\n"
59 "If you wish to commit it anyway, use:\n"
60 "\n"
61 "    git commit --allow-empty\n"
62 "\n"
63 "Otherwise, please use 'git reset'\n");
64
65 static const char *use_message_buffer;
66 static const char commit_editmsg[] = "COMMIT_EDITMSG";
67 static struct lock_file index_lock; /* real index */
68 static struct lock_file false_lock; /* used only for partial commits */
69 static enum {
70         COMMIT_AS_IS = 1,
71         COMMIT_NORMAL,
72         COMMIT_PARTIAL
73 } commit_style;
74
75 static const char *logfile, *force_author;
76 static const char *template_file;
77 /*
78  * The _message variables are commit names from which to take
79  * the commit message and/or authorship.
80  */
81 static const char *author_message, *author_message_buffer;
82 static char *edit_message, *use_message;
83 static char *fixup_message, *squash_message;
84 static int all, edit_flag, also, interactive, patch_interactive, only, amend, signoff;
85 static int quiet, verbose, no_verify, allow_empty, dry_run, renew_authorship;
86 static int no_post_rewrite, allow_empty_message;
87 static char *untracked_files_arg, *force_date, *ignore_submodule_arg;
88 /*
89  * The default commit message cleanup mode will remove the lines
90  * beginning with # (shell comments) and leading and trailing
91  * whitespaces (empty lines or containing only whitespaces)
92  * if editor is used, and only the whitespaces if the message
93  * is specified explicitly.
94  */
95 static enum {
96         CLEANUP_SPACE,
97         CLEANUP_NONE,
98         CLEANUP_ALL
99 } cleanup_mode;
100 static char *cleanup_arg;
101
102 static enum commit_whence whence;
103 static int use_editor = 1, include_status = 1;
104 static int show_ignored_in_status;
105 static const char *only_include_assumed;
106 static struct strbuf message;
107
108 static int null_termination;
109 static enum {
110         STATUS_FORMAT_LONG,
111         STATUS_FORMAT_SHORT,
112         STATUS_FORMAT_PORCELAIN
113 } status_format = STATUS_FORMAT_LONG;
114 static int status_show_branch;
115
116 static int opt_parse_m(const struct option *opt, const char *arg, int unset)
117 {
118         struct strbuf *buf = opt->value;
119         if (unset)
120                 strbuf_setlen(buf, 0);
121         else {
122                 strbuf_addstr(buf, arg);
123                 strbuf_addstr(buf, "\n\n");
124         }
125         return 0;
126 }
127
128 static struct option builtin_commit_options[] = {
129         OPT__QUIET(&quiet, "suppress summary after successful commit"),
130         OPT__VERBOSE(&verbose, "show diff in commit message template"),
131
132         OPT_GROUP("Commit message options"),
133         OPT_FILENAME('F', "file", &logfile, "read message from file"),
134         OPT_STRING(0, "author", &force_author, "author", "override author for commit"),
135         OPT_STRING(0, "date", &force_date, "date", "override date for commit"),
136         OPT_CALLBACK('m', "message", &message, "message", "commit message", opt_parse_m),
137         OPT_STRING('c', "reedit-message", &edit_message, "commit", "reuse and edit message from specified commit"),
138         OPT_STRING('C', "reuse-message", &use_message, "commit", "reuse message from specified commit"),
139         OPT_STRING(0, "fixup", &fixup_message, "commit", "use autosquash formatted message to fixup specified commit"),
140         OPT_STRING(0, "squash", &squash_message, "commit", "use autosquash formatted message to squash specified commit"),
141         OPT_BOOLEAN(0, "reset-author", &renew_authorship, "the commit is authored by me now (used with -C-c/--amend)"),
142         OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by:"),
143         OPT_FILENAME('t', "template", &template_file, "use specified template file"),
144         OPT_BOOLEAN('e', "edit", &edit_flag, "force edit of commit"),
145         OPT_STRING(0, "cleanup", &cleanup_arg, "default", "how to strip spaces and #comments from message"),
146         OPT_BOOLEAN(0, "status", &include_status, "include status in commit message template"),
147         /* end commit message options */
148
149         OPT_GROUP("Commit contents options"),
150         OPT_BOOLEAN('a', "all", &all, "commit all changed files"),
151         OPT_BOOLEAN('i', "include", &also, "add specified files to index for commit"),
152         OPT_BOOLEAN(0, "interactive", &interactive, "interactively add files"),
153         OPT_BOOLEAN('p', "patch", &patch_interactive, "interactively add changes"),
154         OPT_BOOLEAN('o', "only", &only, "commit only specified files"),
155         OPT_BOOLEAN('n', "no-verify", &no_verify, "bypass pre-commit hook"),
156         OPT_BOOLEAN(0, "dry-run", &dry_run, "show what would be committed"),
157         OPT_SET_INT(0, "short", &status_format, "show status concisely",
158                     STATUS_FORMAT_SHORT),
159         OPT_BOOLEAN(0, "branch", &status_show_branch, "show branch information"),
160         OPT_SET_INT(0, "porcelain", &status_format,
161                     "machine-readable output", STATUS_FORMAT_PORCELAIN),
162         OPT_BOOLEAN('z', "null", &null_termination,
163                     "terminate entries with NUL"),
164         OPT_BOOLEAN(0, "amend", &amend, "amend previous commit"),
165         OPT_BOOLEAN(0, "no-post-rewrite", &no_post_rewrite, "bypass post-rewrite hook"),
166         { OPTION_STRING, 'u', "untracked-files", &untracked_files_arg, "mode", "show untracked files, optional modes: all, normal, no. (Default: all)", PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
167         /* end commit contents options */
168
169         { OPTION_BOOLEAN, 0, "allow-empty", &allow_empty, NULL,
170           "ok to record an empty change",
171           PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
172         { OPTION_BOOLEAN, 0, "allow-empty-message", &allow_empty_message, NULL,
173           "ok to record a change with an empty message",
174           PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
175
176         OPT_END()
177 };
178
179 static void determine_whence(struct wt_status *s)
180 {
181         if (file_exists(git_path("MERGE_HEAD")))
182                 whence = FROM_MERGE;
183         else if (file_exists(git_path("CHERRY_PICK_HEAD")))
184                 whence = FROM_CHERRY_PICK;
185         else
186                 whence = FROM_COMMIT;
187         if (s)
188                 s->whence = whence;
189 }
190
191 static const char *whence_s(void)
192 {
193         char *s = "";
194
195         switch (whence) {
196         case FROM_COMMIT:
197                 break;
198         case FROM_MERGE:
199                 s = "merge";
200                 break;
201         case FROM_CHERRY_PICK:
202                 s = "cherry-pick";
203                 break;
204         }
205
206         return s;
207 }
208
209 static void rollback_index_files(void)
210 {
211         switch (commit_style) {
212         case COMMIT_AS_IS:
213                 break; /* nothing to do */
214         case COMMIT_NORMAL:
215                 rollback_lock_file(&index_lock);
216                 break;
217         case COMMIT_PARTIAL:
218                 rollback_lock_file(&index_lock);
219                 rollback_lock_file(&false_lock);
220                 break;
221         }
222 }
223
224 static int commit_index_files(void)
225 {
226         int err = 0;
227
228         switch (commit_style) {
229         case COMMIT_AS_IS:
230                 break; /* nothing to do */
231         case COMMIT_NORMAL:
232                 err = commit_lock_file(&index_lock);
233                 break;
234         case COMMIT_PARTIAL:
235                 err = commit_lock_file(&index_lock);
236                 rollback_lock_file(&false_lock);
237                 break;
238         }
239
240         return err;
241 }
242
243 /*
244  * Take a union of paths in the index and the named tree (typically, "HEAD"),
245  * and return the paths that match the given pattern in list.
246  */
247 static int list_paths(struct string_list *list, const char *with_tree,
248                       const char *prefix, const char **pattern)
249 {
250         int i;
251         char *m;
252
253         for (i = 0; pattern[i]; i++)
254                 ;
255         m = xcalloc(1, i);
256
257         if (with_tree) {
258                 char *max_prefix = common_prefix(pattern);
259                 overlay_tree_on_cache(with_tree, max_prefix ? max_prefix : prefix);
260                 free(max_prefix);
261         }
262
263         for (i = 0; i < active_nr; i++) {
264                 struct cache_entry *ce = active_cache[i];
265                 struct string_list_item *item;
266
267                 if (ce->ce_flags & CE_UPDATE)
268                         continue;
269                 if (!match_pathspec(pattern, ce->name, ce_namelen(ce), 0, m))
270                         continue;
271                 item = string_list_insert(list, ce->name);
272                 if (ce_skip_worktree(ce))
273                         item->util = item; /* better a valid pointer than a fake one */
274         }
275
276         return report_path_error(m, pattern, prefix);
277 }
278
279 static void add_remove_files(struct string_list *list)
280 {
281         int i;
282         for (i = 0; i < list->nr; i++) {
283                 struct stat st;
284                 struct string_list_item *p = &(list->items[i]);
285
286                 /* p->util is skip-worktree */
287                 if (p->util)
288                         continue;
289
290                 if (!lstat(p->string, &st)) {
291                         if (add_to_cache(p->string, &st, 0))
292                                 die(_("updating files failed"));
293                 } else
294                         remove_file_from_cache(p->string);
295         }
296 }
297
298 static void create_base_index(const struct commit *current_head)
299 {
300         struct tree *tree;
301         struct unpack_trees_options opts;
302         struct tree_desc t;
303
304         if (!current_head) {
305                 discard_cache();
306                 return;
307         }
308
309         memset(&opts, 0, sizeof(opts));
310         opts.head_idx = 1;
311         opts.index_only = 1;
312         opts.merge = 1;
313         opts.src_index = &the_index;
314         opts.dst_index = &the_index;
315
316         opts.fn = oneway_merge;
317         tree = parse_tree_indirect(current_head->object.sha1);
318         if (!tree)
319                 die(_("failed to unpack HEAD tree object"));
320         parse_tree(tree);
321         init_tree_desc(&t, tree->buffer, tree->size);
322         if (unpack_trees(1, &t, &opts))
323                 exit(128); /* We've already reported the error, finish dying */
324 }
325
326 static void refresh_cache_or_die(int refresh_flags)
327 {
328         /*
329          * refresh_flags contains REFRESH_QUIET, so the only errors
330          * are for unmerged entries.
331          */
332         if (refresh_cache(refresh_flags | REFRESH_IN_PORCELAIN))
333                 die_resolve_conflict("commit");
334 }
335
336 static char *prepare_index(int argc, const char **argv, const char *prefix,
337                            const struct commit *current_head, int is_status)
338 {
339         int fd;
340         struct string_list partial;
341         const char **pathspec = NULL;
342         char *old_index_env = NULL;
343         int refresh_flags = REFRESH_QUIET;
344
345         if (is_status)
346                 refresh_flags |= REFRESH_UNMERGED;
347
348         if (*argv)
349                 pathspec = get_pathspec(prefix, argv);
350
351         if (read_cache_preload(pathspec) < 0)
352                 die(_("index file corrupt"));
353
354         if (interactive) {
355                 fd = hold_locked_index(&index_lock, 1);
356
357                 refresh_cache_or_die(refresh_flags);
358
359                 if (write_cache(fd, active_cache, active_nr) ||
360                     close_lock_file(&index_lock))
361                         die(_("unable to create temporary index"));
362
363                 old_index_env = getenv(INDEX_ENVIRONMENT);
364                 setenv(INDEX_ENVIRONMENT, index_lock.filename, 1);
365
366                 if (interactive_add(argc, argv, prefix, patch_interactive) != 0)
367                         die(_("interactive add failed"));
368
369                 if (old_index_env && *old_index_env)
370                         setenv(INDEX_ENVIRONMENT, old_index_env, 1);
371                 else
372                         unsetenv(INDEX_ENVIRONMENT);
373
374                 discard_cache();
375                 read_cache_from(index_lock.filename);
376
377                 commit_style = COMMIT_NORMAL;
378                 return index_lock.filename;
379         }
380
381         /*
382          * Non partial, non as-is commit.
383          *
384          * (1) get the real index;
385          * (2) update the_index as necessary;
386          * (3) write the_index out to the real index (still locked);
387          * (4) return the name of the locked index file.
388          *
389          * The caller should run hooks on the locked real index, and
390          * (A) if all goes well, commit the real index;
391          * (B) on failure, rollback the real index.
392          */
393         if (all || (also && pathspec && *pathspec)) {
394                 fd = hold_locked_index(&index_lock, 1);
395                 add_files_to_cache(also ? prefix : NULL, pathspec, 0);
396                 refresh_cache_or_die(refresh_flags);
397                 if (write_cache(fd, active_cache, active_nr) ||
398                     close_lock_file(&index_lock))
399                         die(_("unable to write new_index file"));
400                 commit_style = COMMIT_NORMAL;
401                 return index_lock.filename;
402         }
403
404         /*
405          * As-is commit.
406          *
407          * (1) return the name of the real index file.
408          *
409          * The caller should run hooks on the real index,
410          * and create commit from the_index.
411          * We still need to refresh the index here.
412          */
413         if (!pathspec || !*pathspec) {
414                 fd = hold_locked_index(&index_lock, 1);
415                 refresh_cache_or_die(refresh_flags);
416                 if (active_cache_changed) {
417                         if (write_cache(fd, active_cache, active_nr) ||
418                             commit_locked_index(&index_lock))
419                                 die(_("unable to write new_index file"));
420                 } else {
421                         rollback_lock_file(&index_lock);
422                 }
423                 commit_style = COMMIT_AS_IS;
424                 return get_index_file();
425         }
426
427         /*
428          * A partial commit.
429          *
430          * (0) find the set of affected paths;
431          * (1) get lock on the real index file;
432          * (2) update the_index with the given paths;
433          * (3) write the_index out to the real index (still locked);
434          * (4) get lock on the false index file;
435          * (5) reset the_index from HEAD;
436          * (6) update the_index the same way as (2);
437          * (7) write the_index out to the false index file;
438          * (8) return the name of the false index file (still locked);
439          *
440          * The caller should run hooks on the locked false index, and
441          * create commit from it.  Then
442          * (A) if all goes well, commit the real index;
443          * (B) on failure, rollback the real index;
444          * In either case, rollback the false index.
445          */
446         commit_style = COMMIT_PARTIAL;
447
448         if (whence != FROM_COMMIT)
449                 die(_("cannot do a partial commit during a %s."), whence_s());
450
451         memset(&partial, 0, sizeof(partial));
452         partial.strdup_strings = 1;
453         if (list_paths(&partial, !current_head ? NULL : "HEAD", prefix, pathspec))
454                 exit(1);
455
456         discard_cache();
457         if (read_cache() < 0)
458                 die(_("cannot read the index"));
459
460         fd = hold_locked_index(&index_lock, 1);
461         add_remove_files(&partial);
462         refresh_cache(REFRESH_QUIET);
463         if (write_cache(fd, active_cache, active_nr) ||
464             close_lock_file(&index_lock))
465                 die(_("unable to write new_index file"));
466
467         fd = hold_lock_file_for_update(&false_lock,
468                                        git_path("next-index-%"PRIuMAX,
469                                                 (uintmax_t) getpid()),
470                                        LOCK_DIE_ON_ERROR);
471
472         create_base_index(current_head);
473         add_remove_files(&partial);
474         refresh_cache(REFRESH_QUIET);
475
476         if (write_cache(fd, active_cache, active_nr) ||
477             close_lock_file(&false_lock))
478                 die(_("unable to write temporary index file"));
479
480         discard_cache();
481         read_cache_from(false_lock.filename);
482
483         return false_lock.filename;
484 }
485
486 static int run_status(FILE *fp, const char *index_file, const char *prefix, int nowarn,
487                       struct wt_status *s)
488 {
489         unsigned char sha1[20];
490
491         if (s->relative_paths)
492                 s->prefix = prefix;
493
494         if (amend) {
495                 s->amend = 1;
496                 s->reference = "HEAD^1";
497         }
498         s->verbose = verbose;
499         s->index_file = index_file;
500         s->fp = fp;
501         s->nowarn = nowarn;
502         s->is_initial = get_sha1(s->reference, sha1) ? 1 : 0;
503
504         wt_status_collect(s);
505
506         switch (status_format) {
507         case STATUS_FORMAT_SHORT:
508                 wt_shortstatus_print(s, null_termination, status_show_branch);
509                 break;
510         case STATUS_FORMAT_PORCELAIN:
511                 wt_porcelain_print(s, null_termination);
512                 break;
513         case STATUS_FORMAT_LONG:
514                 wt_status_print(s);
515                 break;
516         }
517
518         return s->commitable;
519 }
520
521 static int is_a_merge(const struct commit *current_head)
522 {
523         return !!(current_head->parents && current_head->parents->next);
524 }
525
526 static const char sign_off_header[] = "Signed-off-by: ";
527
528 static void determine_author_info(struct strbuf *author_ident)
529 {
530         char *name, *email, *date;
531
532         name = getenv("GIT_AUTHOR_NAME");
533         email = getenv("GIT_AUTHOR_EMAIL");
534         date = getenv("GIT_AUTHOR_DATE");
535
536         if (author_message) {
537                 const char *a, *lb, *rb, *eol;
538
539                 a = strstr(author_message_buffer, "\nauthor ");
540                 if (!a)
541                         die(_("invalid commit: %s"), author_message);
542
543                 lb = strchrnul(a + strlen("\nauthor "), '<');
544                 rb = strchrnul(lb, '>');
545                 eol = strchrnul(rb, '\n');
546                 if (!*lb || !*rb || !*eol)
547                         die(_("invalid commit: %s"), author_message);
548
549                 if (lb == a + strlen("\nauthor "))
550                         /* \nauthor <foo@example.com> */
551                         name = xcalloc(1, 1);
552                 else
553                         name = xmemdupz(a + strlen("\nauthor "),
554                                         (lb - strlen(" ") -
555                                          (a + strlen("\nauthor "))));
556                 email = xmemdupz(lb + strlen("<"), rb - (lb + strlen("<")));
557                 date = xmemdupz(rb + strlen("> "), eol - (rb + strlen("> ")));
558         }
559
560         if (force_author) {
561                 const char *lb = strstr(force_author, " <");
562                 const char *rb = strchr(force_author, '>');
563
564                 if (!lb || !rb)
565                         die(_("malformed --author parameter"));
566                 name = xstrndup(force_author, lb - force_author);
567                 email = xstrndup(lb + 2, rb - (lb + 2));
568         }
569
570         if (force_date)
571                 date = force_date;
572         strbuf_addstr(author_ident, fmt_ident(name, email, date,
573                                               IDENT_ERROR_ON_NO_NAME));
574 }
575
576 static int ends_rfc2822_footer(struct strbuf *sb)
577 {
578         int ch;
579         int hit = 0;
580         int i, j, k;
581         int len = sb->len;
582         int first = 1;
583         const char *buf = sb->buf;
584
585         for (i = len - 1; i > 0; i--) {
586                 if (hit && buf[i] == '\n')
587                         break;
588                 hit = (buf[i] == '\n');
589         }
590
591         while (i < len - 1 && buf[i] == '\n')
592                 i++;
593
594         for (; i < len; i = k) {
595                 for (k = i; k < len && buf[k] != '\n'; k++)
596                         ; /* do nothing */
597                 k++;
598
599                 if ((buf[k] == ' ' || buf[k] == '\t') && !first)
600                         continue;
601
602                 first = 0;
603
604                 for (j = 0; i + j < len; j++) {
605                         ch = buf[i + j];
606                         if (ch == ':')
607                                 break;
608                         if (isalnum(ch) ||
609                             (ch == '-'))
610                                 continue;
611                         return 0;
612                 }
613         }
614         return 1;
615 }
616
617 static char *cut_ident_timestamp_part(char *string)
618 {
619         char *ket = strrchr(string, '>');
620         if (!ket || ket[1] != ' ')
621                 die(_("Malformed ident string: '%s'"), string);
622         *++ket = '\0';
623         return ket;
624 }
625
626 static int prepare_to_commit(const char *index_file, const char *prefix,
627                              struct commit *current_head,
628                              struct wt_status *s,
629                              struct strbuf *author_ident)
630 {
631         struct stat statbuf;
632         struct strbuf committer_ident = STRBUF_INIT;
633         int commitable, saved_color_setting;
634         struct strbuf sb = STRBUF_INIT;
635         char *buffer;
636         const char *hook_arg1 = NULL;
637         const char *hook_arg2 = NULL;
638         int ident_shown = 0;
639         int clean_message_contents = (cleanup_mode != CLEANUP_NONE);
640
641         if (!no_verify && run_hook(index_file, "pre-commit", NULL))
642                 return 0;
643
644         if (squash_message) {
645                 /*
646                  * Insert the proper subject line before other commit
647                  * message options add their content.
648                  */
649                 if (use_message && !strcmp(use_message, squash_message))
650                         strbuf_addstr(&sb, "squash! ");
651                 else {
652                         struct pretty_print_context ctx = {0};
653                         struct commit *c;
654                         c = lookup_commit_reference_by_name(squash_message);
655                         if (!c)
656                                 die(_("could not lookup commit %s"), squash_message);
657                         ctx.output_encoding = get_commit_output_encoding();
658                         format_commit_message(c, "squash! %s\n\n", &sb,
659                                               &ctx);
660                 }
661         }
662
663         if (message.len) {
664                 strbuf_addbuf(&sb, &message);
665                 hook_arg1 = "message";
666         } else if (logfile && !strcmp(logfile, "-")) {
667                 if (isatty(0))
668                         fprintf(stderr, _("(reading log message from standard input)\n"));
669                 if (strbuf_read(&sb, 0, 0) < 0)
670                         die_errno(_("could not read log from standard input"));
671                 hook_arg1 = "message";
672         } else if (logfile) {
673                 if (strbuf_read_file(&sb, logfile, 0) < 0)
674                         die_errno(_("could not read log file '%s'"),
675                                   logfile);
676                 hook_arg1 = "message";
677         } else if (use_message) {
678                 buffer = strstr(use_message_buffer, "\n\n");
679                 if (!buffer || buffer[2] == '\0')
680                         die(_("commit has empty message"));
681                 strbuf_add(&sb, buffer + 2, strlen(buffer + 2));
682                 hook_arg1 = "commit";
683                 hook_arg2 = use_message;
684         } else if (fixup_message) {
685                 struct pretty_print_context ctx = {0};
686                 struct commit *commit;
687                 commit = lookup_commit_reference_by_name(fixup_message);
688                 if (!commit)
689                         die(_("could not lookup commit %s"), fixup_message);
690                 ctx.output_encoding = get_commit_output_encoding();
691                 format_commit_message(commit, "fixup! %s\n\n",
692                                       &sb, &ctx);
693                 hook_arg1 = "message";
694         } else if (!stat(git_path("MERGE_MSG"), &statbuf)) {
695                 if (strbuf_read_file(&sb, git_path("MERGE_MSG"), 0) < 0)
696                         die_errno(_("could not read MERGE_MSG"));
697                 hook_arg1 = "merge";
698         } else if (!stat(git_path("SQUASH_MSG"), &statbuf)) {
699                 if (strbuf_read_file(&sb, git_path("SQUASH_MSG"), 0) < 0)
700                         die_errno(_("could not read SQUASH_MSG"));
701                 hook_arg1 = "squash";
702         } else if (template_file) {
703                 if (strbuf_read_file(&sb, template_file, 0) < 0)
704                         die_errno(_("could not read '%s'"), template_file);
705                 hook_arg1 = "template";
706                 clean_message_contents = 0;
707         }
708
709         /*
710          * The remaining cases don't modify the template message, but
711          * just set the argument(s) to the prepare-commit-msg hook.
712          */
713         else if (whence == FROM_MERGE)
714                 hook_arg1 = "merge";
715         else if (whence == FROM_CHERRY_PICK) {
716                 hook_arg1 = "commit";
717                 hook_arg2 = "CHERRY_PICK_HEAD";
718         }
719
720         if (squash_message) {
721                 /*
722                  * If squash_commit was used for the commit subject,
723                  * then we're possibly hijacking other commit log options.
724                  * Reset the hook args to tell the real story.
725                  */
726                 hook_arg1 = "message";
727                 hook_arg2 = "";
728         }
729
730         s->fp = fopen(git_path(commit_editmsg), "w");
731         if (s->fp == NULL)
732                 die_errno(_("could not open '%s'"), git_path(commit_editmsg));
733
734         if (clean_message_contents)
735                 stripspace(&sb, 0);
736
737         if (signoff) {
738                 struct strbuf sob = STRBUF_INIT;
739                 int i;
740
741                 strbuf_addstr(&sob, sign_off_header);
742                 strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
743                                              getenv("GIT_COMMITTER_EMAIL")));
744                 strbuf_addch(&sob, '\n');
745                 for (i = sb.len - 1; i > 0 && sb.buf[i - 1] != '\n'; i--)
746                         ; /* do nothing */
747                 if (prefixcmp(sb.buf + i, sob.buf)) {
748                         if (!i || !ends_rfc2822_footer(&sb))
749                                 strbuf_addch(&sb, '\n');
750                         strbuf_addbuf(&sb, &sob);
751                 }
752                 strbuf_release(&sob);
753         }
754
755         if (fwrite(sb.buf, 1, sb.len, s->fp) < sb.len)
756                 die_errno(_("could not write commit template"));
757
758         strbuf_release(&sb);
759
760         /* This checks and barfs if author is badly specified */
761         determine_author_info(author_ident);
762
763         /* This checks if committer ident is explicitly given */
764         strbuf_addstr(&committer_ident, git_committer_info(0));
765         if (use_editor && include_status) {
766                 char *ai_tmp, *ci_tmp;
767                 if (whence != FROM_COMMIT)
768                         status_printf_ln(s, GIT_COLOR_NORMAL,
769                                 _("\n"
770                                 "It looks like you may be committing a %s.\n"
771                                 "If this is not correct, please remove the file\n"
772                                 "       %s\n"
773                                 "and try again.\n"
774                                 ""),
775                                 whence_s(),
776                                 git_path(whence == FROM_MERGE
777                                          ? "MERGE_HEAD"
778                                          : "CHERRY_PICK_HEAD"));
779
780                 fprintf(s->fp, "\n");
781                 status_printf(s, GIT_COLOR_NORMAL,
782                         _("Please enter the commit message for your changes."));
783                 if (cleanup_mode == CLEANUP_ALL)
784                         status_printf_more(s, GIT_COLOR_NORMAL,
785                                 _(" Lines starting\n"
786                                 "with '#' will be ignored, and an empty"
787                                 " message aborts the commit.\n"));
788                 else /* CLEANUP_SPACE, that is. */
789                         status_printf_more(s, GIT_COLOR_NORMAL,
790                                 _(" Lines starting\n"
791                                 "with '#' will be kept; you may remove them"
792                                 " yourself if you want to.\n"
793                                 "An empty message aborts the commit.\n"));
794                 if (only_include_assumed)
795                         status_printf_ln(s, GIT_COLOR_NORMAL,
796                                         "%s", only_include_assumed);
797
798                 ai_tmp = cut_ident_timestamp_part(author_ident->buf);
799                 ci_tmp = cut_ident_timestamp_part(committer_ident.buf);
800                 if (strcmp(author_ident->buf, committer_ident.buf))
801                         status_printf_ln(s, GIT_COLOR_NORMAL,
802                                 _("%s"
803                                 "Author:    %s"),
804                                 ident_shown++ ? "" : "\n",
805                                 author_ident->buf);
806
807                 if (!user_ident_sufficiently_given())
808                         status_printf_ln(s, GIT_COLOR_NORMAL,
809                                 _("%s"
810                                 "Committer: %s"),
811                                 ident_shown++ ? "" : "\n",
812                                 committer_ident.buf);
813
814                 if (ident_shown)
815                         status_printf_ln(s, GIT_COLOR_NORMAL, "");
816
817                 saved_color_setting = s->use_color;
818                 s->use_color = 0;
819                 commitable = run_status(s->fp, index_file, prefix, 1, s);
820                 s->use_color = saved_color_setting;
821
822                 *ai_tmp = ' ';
823                 *ci_tmp = ' ';
824         } else {
825                 unsigned char sha1[20];
826                 const char *parent = "HEAD";
827
828                 if (!active_nr && read_cache() < 0)
829                         die(_("Cannot read index"));
830
831                 if (amend)
832                         parent = "HEAD^1";
833
834                 if (get_sha1(parent, sha1))
835                         commitable = !!active_nr;
836                 else
837                         commitable = index_differs_from(parent, 0);
838         }
839         strbuf_release(&committer_ident);
840
841         fclose(s->fp);
842
843         /*
844          * Reject an attempt to record a non-merge empty commit without
845          * explicit --allow-empty. In the cherry-pick case, it may be
846          * empty due to conflict resolution, which the user should okay.
847          */
848         if (!commitable && whence != FROM_MERGE && !allow_empty &&
849             !(amend && is_a_merge(current_head))) {
850                 run_status(stdout, index_file, prefix, 0, s);
851                 if (amend)
852                         fputs(_(empty_amend_advice), stderr);
853                 else if (whence == FROM_CHERRY_PICK)
854                         fputs(_(empty_cherry_pick_advice), stderr);
855                 return 0;
856         }
857
858         /*
859          * Re-read the index as pre-commit hook could have updated it,
860          * and write it out as a tree.  We must do this before we invoke
861          * the editor and after we invoke run_status above.
862          */
863         discard_cache();
864         read_cache_from(index_file);
865         if (!active_cache_tree)
866                 active_cache_tree = cache_tree();
867         if (cache_tree_update(active_cache_tree,
868                               active_cache, active_nr, 0, 0) < 0) {
869                 error(_("Error building trees"));
870                 return 0;
871         }
872
873         if (run_hook(index_file, "prepare-commit-msg",
874                      git_path(commit_editmsg), hook_arg1, hook_arg2, NULL))
875                 return 0;
876
877         if (use_editor) {
878                 char index[PATH_MAX];
879                 const char *env[2] = { NULL };
880                 env[0] =  index;
881                 snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
882                 if (launch_editor(git_path(commit_editmsg), NULL, env)) {
883                         fprintf(stderr,
884                         _("Please supply the message using either -m or -F option.\n"));
885                         exit(1);
886                 }
887         }
888
889         if (!no_verify &&
890             run_hook(index_file, "commit-msg", git_path(commit_editmsg), NULL)) {
891                 return 0;
892         }
893
894         return 1;
895 }
896
897 /*
898  * Find out if the message in the strbuf contains only whitespace and
899  * Signed-off-by lines.
900  */
901 static int message_is_empty(struct strbuf *sb)
902 {
903         struct strbuf tmpl = STRBUF_INIT;
904         const char *nl;
905         int eol, i, start = 0;
906
907         if (cleanup_mode == CLEANUP_NONE && sb->len)
908                 return 0;
909
910         /* See if the template is just a prefix of the message. */
911         if (template_file && strbuf_read_file(&tmpl, template_file, 0) > 0) {
912                 stripspace(&tmpl, cleanup_mode == CLEANUP_ALL);
913                 if (start + tmpl.len <= sb->len &&
914                     memcmp(tmpl.buf, sb->buf + start, tmpl.len) == 0)
915                         start += tmpl.len;
916         }
917         strbuf_release(&tmpl);
918
919         /* Check if the rest is just whitespace and Signed-of-by's. */
920         for (i = start; i < sb->len; i++) {
921                 nl = memchr(sb->buf + i, '\n', sb->len - i);
922                 if (nl)
923                         eol = nl - sb->buf;
924                 else
925                         eol = sb->len;
926
927                 if (strlen(sign_off_header) <= eol - i &&
928                     !prefixcmp(sb->buf + i, sign_off_header)) {
929                         i = eol;
930                         continue;
931                 }
932                 while (i < eol)
933                         if (!isspace(sb->buf[i++]))
934                                 return 0;
935         }
936
937         return 1;
938 }
939
940 static const char *find_author_by_nickname(const char *name)
941 {
942         struct rev_info revs;
943         struct commit *commit;
944         struct strbuf buf = STRBUF_INIT;
945         const char *av[20];
946         int ac = 0;
947
948         init_revisions(&revs, NULL);
949         strbuf_addf(&buf, "--author=%s", name);
950         av[++ac] = "--all";
951         av[++ac] = "-i";
952         av[++ac] = buf.buf;
953         av[++ac] = NULL;
954         setup_revisions(ac, av, &revs, NULL);
955         prepare_revision_walk(&revs);
956         commit = get_revision(&revs);
957         if (commit) {
958                 struct pretty_print_context ctx = {0};
959                 ctx.date_mode = DATE_NORMAL;
960                 strbuf_release(&buf);
961                 format_commit_message(commit, "%an <%ae>", &buf, &ctx);
962                 return strbuf_detach(&buf, NULL);
963         }
964         die(_("No existing author found with '%s'"), name);
965 }
966
967
968 static void handle_untracked_files_arg(struct wt_status *s)
969 {
970         if (!untracked_files_arg)
971                 ; /* default already initialized */
972         else if (!strcmp(untracked_files_arg, "no"))
973                 s->show_untracked_files = SHOW_NO_UNTRACKED_FILES;
974         else if (!strcmp(untracked_files_arg, "normal"))
975                 s->show_untracked_files = SHOW_NORMAL_UNTRACKED_FILES;
976         else if (!strcmp(untracked_files_arg, "all"))
977                 s->show_untracked_files = SHOW_ALL_UNTRACKED_FILES;
978         else
979                 die(_("Invalid untracked files mode '%s'"), untracked_files_arg);
980 }
981
982 static const char *read_commit_message(const char *name)
983 {
984         const char *out_enc, *out;
985         struct commit *commit;
986
987         commit = lookup_commit_reference_by_name(name);
988         if (!commit)
989                 die(_("could not lookup commit %s"), name);
990         out_enc = get_commit_output_encoding();
991         out = logmsg_reencode(commit, out_enc);
992
993         /*
994          * If we failed to reencode the buffer, just copy it
995          * byte for byte so the user can try to fix it up.
996          * This also handles the case where input and output
997          * encodings are identical.
998          */
999         if (out == NULL)
1000                 out = xstrdup(commit->buffer);
1001         return out;
1002 }
1003
1004 static int parse_and_validate_options(int argc, const char *argv[],
1005                                       const char * const usage[],
1006                                       const char *prefix,
1007                                       struct commit *current_head,
1008                                       struct wt_status *s)
1009 {
1010         int f = 0;
1011
1012         argc = parse_options(argc, argv, prefix, builtin_commit_options, usage,
1013                              0);
1014
1015         if (force_author && !strchr(force_author, '>'))
1016                 force_author = find_author_by_nickname(force_author);
1017
1018         if (force_author && renew_authorship)
1019                 die(_("Using both --reset-author and --author does not make sense"));
1020
1021         if (logfile || message.len || use_message || fixup_message)
1022                 use_editor = 0;
1023         if (edit_flag)
1024                 use_editor = 1;
1025         if (!use_editor)
1026                 setenv("GIT_EDITOR", ":", 1);
1027
1028         /* Sanity check options */
1029         if (amend && !current_head)
1030                 die(_("You have nothing to amend."));
1031         if (amend && whence != FROM_COMMIT)
1032                 die(_("You are in the middle of a %s -- cannot amend."), whence_s());
1033         if (fixup_message && squash_message)
1034                 die(_("Options --squash and --fixup cannot be used together"));
1035         if (use_message)
1036                 f++;
1037         if (edit_message)
1038                 f++;
1039         if (fixup_message)
1040                 f++;
1041         if (logfile)
1042                 f++;
1043         if (f > 1)
1044                 die(_("Only one of -c/-C/-F/--fixup can be used."));
1045         if (message.len && f > 0)
1046                 die((_("Option -m cannot be combined with -c/-C/-F/--fixup.")));
1047         if (edit_message)
1048                 use_message = edit_message;
1049         if (amend && !use_message && !fixup_message)
1050                 use_message = "HEAD";
1051         if (!use_message && whence != FROM_CHERRY_PICK && renew_authorship)
1052                 die(_("--reset-author can be used only with -C, -c or --amend."));
1053         if (use_message) {
1054                 use_message_buffer = read_commit_message(use_message);
1055                 if (!renew_authorship) {
1056                         author_message = use_message;
1057                         author_message_buffer = use_message_buffer;
1058                 }
1059         }
1060         if (whence == FROM_CHERRY_PICK && !renew_authorship) {
1061                 author_message = "CHERRY_PICK_HEAD";
1062                 author_message_buffer = read_commit_message(author_message);
1063         }
1064
1065         if (patch_interactive)
1066                 interactive = 1;
1067
1068         if (!!also + !!only + !!all + !!interactive > 1)
1069                 die(_("Only one of --include/--only/--all/--interactive/--patch can be used."));
1070         if (argc == 0 && (also || (only && !amend)))
1071                 die(_("No paths with --include/--only does not make sense."));
1072         if (argc == 0 && only && amend)
1073                 only_include_assumed = _("Clever... amending the last one with dirty index.");
1074         if (argc > 0 && !also && !only)
1075                 only_include_assumed = _("Explicit paths specified without -i nor -o; assuming --only paths...");
1076         if (!cleanup_arg || !strcmp(cleanup_arg, "default"))
1077                 cleanup_mode = use_editor ? CLEANUP_ALL : CLEANUP_SPACE;
1078         else if (!strcmp(cleanup_arg, "verbatim"))
1079                 cleanup_mode = CLEANUP_NONE;
1080         else if (!strcmp(cleanup_arg, "whitespace"))
1081                 cleanup_mode = CLEANUP_SPACE;
1082         else if (!strcmp(cleanup_arg, "strip"))
1083                 cleanup_mode = CLEANUP_ALL;
1084         else
1085                 die(_("Invalid cleanup mode %s"), cleanup_arg);
1086
1087         handle_untracked_files_arg(s);
1088
1089         if (all && argc > 0)
1090                 die(_("Paths with -a does not make sense."));
1091
1092         if (null_termination && status_format == STATUS_FORMAT_LONG)
1093                 status_format = STATUS_FORMAT_PORCELAIN;
1094         if (status_format != STATUS_FORMAT_LONG)
1095                 dry_run = 1;
1096
1097         return argc;
1098 }
1099
1100 static int dry_run_commit(int argc, const char **argv, const char *prefix,
1101                           const struct commit *current_head, struct wt_status *s)
1102 {
1103         int commitable;
1104         const char *index_file;
1105
1106         index_file = prepare_index(argc, argv, prefix, current_head, 1);
1107         commitable = run_status(stdout, index_file, prefix, 0, s);
1108         rollback_index_files();
1109
1110         return commitable ? 0 : 1;
1111 }
1112
1113 static int parse_status_slot(const char *var, int offset)
1114 {
1115         if (!strcasecmp(var+offset, "header"))
1116                 return WT_STATUS_HEADER;
1117         if (!strcasecmp(var+offset, "branch"))
1118                 return WT_STATUS_ONBRANCH;
1119         if (!strcasecmp(var+offset, "updated")
1120                 || !strcasecmp(var+offset, "added"))
1121                 return WT_STATUS_UPDATED;
1122         if (!strcasecmp(var+offset, "changed"))
1123                 return WT_STATUS_CHANGED;
1124         if (!strcasecmp(var+offset, "untracked"))
1125                 return WT_STATUS_UNTRACKED;
1126         if (!strcasecmp(var+offset, "nobranch"))
1127                 return WT_STATUS_NOBRANCH;
1128         if (!strcasecmp(var+offset, "unmerged"))
1129                 return WT_STATUS_UNMERGED;
1130         return -1;
1131 }
1132
1133 static int git_status_config(const char *k, const char *v, void *cb)
1134 {
1135         struct wt_status *s = cb;
1136
1137         if (!strcmp(k, "status.submodulesummary")) {
1138                 int is_bool;
1139                 s->submodule_summary = git_config_bool_or_int(k, v, &is_bool);
1140                 if (is_bool && s->submodule_summary)
1141                         s->submodule_summary = -1;
1142                 return 0;
1143         }
1144         if (!strcmp(k, "status.color") || !strcmp(k, "color.status")) {
1145                 s->use_color = git_config_colorbool(k, v);
1146                 return 0;
1147         }
1148         if (!prefixcmp(k, "status.color.") || !prefixcmp(k, "color.status.")) {
1149                 int slot = parse_status_slot(k, 13);
1150                 if (slot < 0)
1151                         return 0;
1152                 if (!v)
1153                         return config_error_nonbool(k);
1154                 color_parse(v, k, s->color_palette[slot]);
1155                 return 0;
1156         }
1157         if (!strcmp(k, "status.relativepaths")) {
1158                 s->relative_paths = git_config_bool(k, v);
1159                 return 0;
1160         }
1161         if (!strcmp(k, "status.showuntrackedfiles")) {
1162                 if (!v)
1163                         return config_error_nonbool(k);
1164                 else if (!strcmp(v, "no"))
1165                         s->show_untracked_files = SHOW_NO_UNTRACKED_FILES;
1166                 else if (!strcmp(v, "normal"))
1167                         s->show_untracked_files = SHOW_NORMAL_UNTRACKED_FILES;
1168                 else if (!strcmp(v, "all"))
1169                         s->show_untracked_files = SHOW_ALL_UNTRACKED_FILES;
1170                 else
1171                         return error(_("Invalid untracked files mode '%s'"), v);
1172                 return 0;
1173         }
1174         return git_diff_ui_config(k, v, NULL);
1175 }
1176
1177 int cmd_status(int argc, const char **argv, const char *prefix)
1178 {
1179         struct wt_status s;
1180         int fd;
1181         unsigned char sha1[20];
1182         static struct option builtin_status_options[] = {
1183                 OPT__VERBOSE(&verbose, "be verbose"),
1184                 OPT_SET_INT('s', "short", &status_format,
1185                             "show status concisely", STATUS_FORMAT_SHORT),
1186                 OPT_BOOLEAN('b', "branch", &status_show_branch,
1187                             "show branch information"),
1188                 OPT_SET_INT(0, "porcelain", &status_format,
1189                             "machine-readable output",
1190                             STATUS_FORMAT_PORCELAIN),
1191                 OPT_BOOLEAN('z', "null", &null_termination,
1192                             "terminate entries with NUL"),
1193                 { OPTION_STRING, 'u', "untracked-files", &untracked_files_arg,
1194                   "mode",
1195                   "show untracked files, optional modes: all, normal, no. (Default: all)",
1196                   PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
1197                 OPT_BOOLEAN(0, "ignored", &show_ignored_in_status,
1198                             "show ignored files"),
1199                 { OPTION_STRING, 0, "ignore-submodules", &ignore_submodule_arg, "when",
1200                   "ignore changes to submodules, optional when: all, dirty, untracked. (Default: all)",
1201                   PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
1202                 OPT_END(),
1203         };
1204
1205         if (argc == 2 && !strcmp(argv[1], "-h"))
1206                 usage_with_options(builtin_status_usage, builtin_status_options);
1207
1208         wt_status_prepare(&s);
1209         gitmodules_config();
1210         git_config(git_status_config, &s);
1211         determine_whence(&s);
1212         argc = parse_options(argc, argv, prefix,
1213                              builtin_status_options,
1214                              builtin_status_usage, 0);
1215
1216         if (null_termination && status_format == STATUS_FORMAT_LONG)
1217                 status_format = STATUS_FORMAT_PORCELAIN;
1218
1219         handle_untracked_files_arg(&s);
1220         if (show_ignored_in_status)
1221                 s.show_ignored_files = 1;
1222         if (*argv)
1223                 s.pathspec = get_pathspec(prefix, argv);
1224
1225         read_cache_preload(s.pathspec);
1226         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, s.pathspec, NULL, NULL);
1227
1228         fd = hold_locked_index(&index_lock, 0);
1229         if (0 <= fd)
1230                 update_index_if_able(&the_index, &index_lock);
1231
1232         s.is_initial = get_sha1(s.reference, sha1) ? 1 : 0;
1233         s.ignore_submodule_arg = ignore_submodule_arg;
1234         wt_status_collect(&s);
1235
1236         if (s.relative_paths)
1237                 s.prefix = prefix;
1238
1239         switch (status_format) {
1240         case STATUS_FORMAT_SHORT:
1241                 wt_shortstatus_print(&s, null_termination, status_show_branch);
1242                 break;
1243         case STATUS_FORMAT_PORCELAIN:
1244                 wt_porcelain_print(&s, null_termination);
1245                 break;
1246         case STATUS_FORMAT_LONG:
1247                 s.verbose = verbose;
1248                 s.ignore_submodule_arg = ignore_submodule_arg;
1249                 wt_status_print(&s);
1250                 break;
1251         }
1252         return 0;
1253 }
1254
1255 static void print_summary(const char *prefix, const unsigned char *sha1,
1256                           int initial_commit)
1257 {
1258         struct rev_info rev;
1259         struct commit *commit;
1260         struct strbuf format = STRBUF_INIT;
1261         unsigned char junk_sha1[20];
1262         const char *head;
1263         struct pretty_print_context pctx = {0};
1264         struct strbuf author_ident = STRBUF_INIT;
1265         struct strbuf committer_ident = STRBUF_INIT;
1266
1267         commit = lookup_commit(sha1);
1268         if (!commit)
1269                 die(_("couldn't look up newly created commit"));
1270         if (!commit || parse_commit(commit))
1271                 die(_("could not parse newly created commit"));
1272
1273         strbuf_addstr(&format, "format:%h] %s");
1274
1275         format_commit_message(commit, "%an <%ae>", &author_ident, &pctx);
1276         format_commit_message(commit, "%cn <%ce>", &committer_ident, &pctx);
1277         if (strbuf_cmp(&author_ident, &committer_ident)) {
1278                 strbuf_addstr(&format, "\n Author: ");
1279                 strbuf_addbuf_percentquote(&format, &author_ident);
1280         }
1281         if (!user_ident_sufficiently_given()) {
1282                 strbuf_addstr(&format, "\n Committer: ");
1283                 strbuf_addbuf_percentquote(&format, &committer_ident);
1284                 if (advice_implicit_identity) {
1285                         strbuf_addch(&format, '\n');
1286                         strbuf_addstr(&format, _(implicit_ident_advice));
1287                 }
1288         }
1289         strbuf_release(&author_ident);
1290         strbuf_release(&committer_ident);
1291
1292         init_revisions(&rev, prefix);
1293         setup_revisions(0, NULL, &rev, NULL);
1294
1295         rev.diff = 1;
1296         rev.diffopt.output_format =
1297                 DIFF_FORMAT_SHORTSTAT | DIFF_FORMAT_SUMMARY;
1298
1299         rev.verbose_header = 1;
1300         rev.show_root_diff = 1;
1301         get_commit_format(format.buf, &rev);
1302         rev.always_show_header = 0;
1303         rev.diffopt.detect_rename = 1;
1304         rev.diffopt.break_opt = 0;
1305         diff_setup_done(&rev.diffopt);
1306
1307         head = resolve_ref("HEAD", junk_sha1, 0, NULL);
1308         printf("[%s%s ",
1309                 !prefixcmp(head, "refs/heads/") ?
1310                         head + 11 :
1311                         !strcmp(head, "HEAD") ?
1312                                 _("detached HEAD") :
1313                                 head,
1314                 initial_commit ? _(" (root-commit)") : "");
1315
1316         if (!log_tree_commit(&rev, commit)) {
1317                 rev.always_show_header = 1;
1318                 rev.use_terminator = 1;
1319                 log_tree_commit(&rev, commit);
1320         }
1321
1322         strbuf_release(&format);
1323 }
1324
1325 static int git_commit_config(const char *k, const char *v, void *cb)
1326 {
1327         struct wt_status *s = cb;
1328
1329         if (!strcmp(k, "commit.template"))
1330                 return git_config_pathname(&template_file, k, v);
1331         if (!strcmp(k, "commit.status")) {
1332                 include_status = git_config_bool(k, v);
1333                 return 0;
1334         }
1335
1336         return git_status_config(k, v, s);
1337 }
1338
1339 static const char post_rewrite_hook[] = "hooks/post-rewrite";
1340
1341 static int run_rewrite_hook(const unsigned char *oldsha1,
1342                             const unsigned char *newsha1)
1343 {
1344         /* oldsha1 SP newsha1 LF NUL */
1345         static char buf[2*40 + 3];
1346         struct child_process proc;
1347         const char *argv[3];
1348         int code;
1349         size_t n;
1350
1351         if (access(git_path(post_rewrite_hook), X_OK) < 0)
1352                 return 0;
1353
1354         argv[0] = git_path(post_rewrite_hook);
1355         argv[1] = "amend";
1356         argv[2] = NULL;
1357
1358         memset(&proc, 0, sizeof(proc));
1359         proc.argv = argv;
1360         proc.in = -1;
1361         proc.stdout_to_stderr = 1;
1362
1363         code = start_command(&proc);
1364         if (code)
1365                 return code;
1366         n = snprintf(buf, sizeof(buf), "%s %s\n",
1367                      sha1_to_hex(oldsha1), sha1_to_hex(newsha1));
1368         write_in_full(proc.in, buf, n);
1369         close(proc.in);
1370         return finish_command(&proc);
1371 }
1372
1373 int cmd_commit(int argc, const char **argv, const char *prefix)
1374 {
1375         struct strbuf sb = STRBUF_INIT;
1376         struct strbuf author_ident = STRBUF_INIT;
1377         const char *index_file, *reflog_msg;
1378         char *nl, *p;
1379         unsigned char sha1[20];
1380         struct ref_lock *ref_lock;
1381         struct commit_list *parents = NULL, **pptr = &parents;
1382         struct stat statbuf;
1383         int allow_fast_forward = 1;
1384         struct wt_status s;
1385         struct commit *current_head = NULL;
1386         struct commit_extra_header *extra = NULL;
1387
1388         if (argc == 2 && !strcmp(argv[1], "-h"))
1389                 usage_with_options(builtin_commit_usage, builtin_commit_options);
1390
1391         wt_status_prepare(&s);
1392         git_config(git_commit_config, &s);
1393         determine_whence(&s);
1394
1395         if (get_sha1("HEAD", sha1))
1396                 current_head = NULL;
1397         else {
1398                 current_head = lookup_commit_or_die(sha1, "HEAD");
1399                 if (!current_head || parse_commit(current_head))
1400                         die(_("could not parse HEAD commit"));
1401         }
1402         argc = parse_and_validate_options(argc, argv, builtin_commit_usage,
1403                                           prefix, current_head, &s);
1404         if (dry_run)
1405                 return dry_run_commit(argc, argv, prefix, current_head, &s);
1406         index_file = prepare_index(argc, argv, prefix, current_head, 0);
1407
1408         /* Set up everything for writing the commit object.  This includes
1409            running hooks, writing the trees, and interacting with the user.  */
1410         if (!prepare_to_commit(index_file, prefix,
1411                                current_head, &s, &author_ident)) {
1412                 rollback_index_files();
1413                 return 1;
1414         }
1415
1416         /* Determine parents */
1417         reflog_msg = getenv("GIT_REFLOG_ACTION");
1418         if (!current_head) {
1419                 if (!reflog_msg)
1420                         reflog_msg = "commit (initial)";
1421         } else if (amend) {
1422                 struct commit_list *c;
1423
1424                 if (!reflog_msg)
1425                         reflog_msg = "commit (amend)";
1426                 for (c = current_head->parents; c; c = c->next)
1427                         pptr = &commit_list_insert(c->item, pptr)->next;
1428         } else if (whence == FROM_MERGE) {
1429                 struct strbuf m = STRBUF_INIT;
1430                 FILE *fp;
1431
1432                 if (!reflog_msg)
1433                         reflog_msg = "commit (merge)";
1434                 pptr = &commit_list_insert(current_head, pptr)->next;
1435                 fp = fopen(git_path("MERGE_HEAD"), "r");
1436                 if (fp == NULL)
1437                         die_errno(_("could not open '%s' for reading"),
1438                                   git_path("MERGE_HEAD"));
1439                 while (strbuf_getline(&m, fp, '\n') != EOF) {
1440                         struct commit *parent;
1441
1442                         parent = get_merge_parent(m.buf);
1443                         if (!parent)
1444                                 die(_("Corrupt MERGE_HEAD file (%s)"), m.buf);
1445                         pptr = &commit_list_insert(parent, pptr)->next;
1446                 }
1447                 fclose(fp);
1448                 strbuf_release(&m);
1449                 if (!stat(git_path("MERGE_MODE"), &statbuf)) {
1450                         if (strbuf_read_file(&sb, git_path("MERGE_MODE"), 0) < 0)
1451                                 die_errno(_("could not read MERGE_MODE"));
1452                         if (!strcmp(sb.buf, "no-ff"))
1453                                 allow_fast_forward = 0;
1454                 }
1455                 if (allow_fast_forward)
1456                         parents = reduce_heads(parents);
1457         } else {
1458                 if (!reflog_msg)
1459                         reflog_msg = (whence == FROM_CHERRY_PICK)
1460                                         ? "commit (cherry-pick)"
1461                                         : "commit";
1462                 pptr = &commit_list_insert(current_head, pptr)->next;
1463         }
1464
1465         /* Finally, get the commit message */
1466         strbuf_reset(&sb);
1467         if (strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0) {
1468                 int saved_errno = errno;
1469                 rollback_index_files();
1470                 die(_("could not read commit message: %s"), strerror(saved_errno));
1471         }
1472
1473         /* Truncate the message just before the diff, if any. */
1474         if (verbose) {
1475                 p = strstr(sb.buf, "\ndiff --git ");
1476                 if (p != NULL)
1477                         strbuf_setlen(&sb, p - sb.buf + 1);
1478         }
1479
1480         if (cleanup_mode != CLEANUP_NONE)
1481                 stripspace(&sb, cleanup_mode == CLEANUP_ALL);
1482         if (message_is_empty(&sb) && !allow_empty_message) {
1483                 rollback_index_files();
1484                 fprintf(stderr, _("Aborting commit due to empty commit message.\n"));
1485                 exit(1);
1486         }
1487
1488         if (amend)
1489                 extra = read_commit_extra_headers(current_head);
1490
1491         if (commit_tree_extended(sb.buf, active_cache_tree->sha1, parents, sha1,
1492                                  author_ident.buf, extra)) {
1493                 rollback_index_files();
1494                 die(_("failed to write commit object"));
1495         }
1496         strbuf_release(&author_ident);
1497         free_commit_extra_headers(extra);
1498
1499         ref_lock = lock_any_ref_for_update("HEAD",
1500                                            !current_head
1501                                            ? NULL
1502                                            : current_head->object.sha1,
1503                                            0);
1504
1505         nl = strchr(sb.buf, '\n');
1506         if (nl)
1507                 strbuf_setlen(&sb, nl + 1 - sb.buf);
1508         else
1509                 strbuf_addch(&sb, '\n');
1510         strbuf_insert(&sb, 0, reflog_msg, strlen(reflog_msg));
1511         strbuf_insert(&sb, strlen(reflog_msg), ": ", 2);
1512
1513         if (!ref_lock) {
1514                 rollback_index_files();
1515                 die(_("cannot lock HEAD ref"));
1516         }
1517         if (write_ref_sha1(ref_lock, sha1, sb.buf) < 0) {
1518                 rollback_index_files();
1519                 die(_("cannot update HEAD ref"));
1520         }
1521
1522         unlink(git_path("CHERRY_PICK_HEAD"));
1523         unlink(git_path("REVERT_HEAD"));
1524         unlink(git_path("MERGE_HEAD"));
1525         unlink(git_path("MERGE_MSG"));
1526         unlink(git_path("MERGE_MODE"));
1527         unlink(git_path("SQUASH_MSG"));
1528
1529         if (commit_index_files())
1530                 die (_("Repository has been updated, but unable to write\n"
1531                      "new_index file. Check that disk is not full or quota is\n"
1532                      "not exceeded, and then \"git reset HEAD\" to recover."));
1533
1534         rerere(0);
1535         run_hook(get_index_file(), "post-commit", NULL);
1536         if (amend && !no_post_rewrite) {
1537                 struct notes_rewrite_cfg *cfg;
1538                 cfg = init_copy_notes_for_rewrite("amend");
1539                 if (cfg) {
1540                         /* we are amending, so current_head is not NULL */
1541                         copy_note_for_rewrite(cfg, current_head->object.sha1, sha1);
1542                         finish_copy_notes_for_rewrite(cfg);
1543                 }
1544                 run_rewrite_hook(current_head->object.sha1, sha1);
1545         }
1546         if (!quiet)
1547                 print_summary(prefix, sha1, !current_head);
1548
1549         return 0;
1550 }