cherry-pick, revert: add a label for ancestor
[git] / builtin / log.c
1 /*
2  * Builtin "git log" and related commands (show, whatchanged)
3  *
4  * (C) Copyright 2006 Linus Torvalds
5  *               2006 Junio Hamano
6  */
7 #include "cache.h"
8 #include "color.h"
9 #include "commit.h"
10 #include "diff.h"
11 #include "revision.h"
12 #include "log-tree.h"
13 #include "builtin.h"
14 #include "tag.h"
15 #include "reflog-walk.h"
16 #include "patch-ids.h"
17 #include "run-command.h"
18 #include "shortlog.h"
19 #include "remote.h"
20 #include "string-list.h"
21 #include "parse-options.h"
22
23 /* Set a default date-time format for git log ("log.date" config variable) */
24 static const char *default_date_mode = NULL;
25
26 static int default_show_root = 1;
27 static const char *fmt_patch_subject_prefix = "PATCH";
28 static const char *fmt_pretty;
29
30 static const char * const builtin_log_usage =
31         "git log [<options>] [<since>..<until>] [[--] <path>...]\n"
32         "   or: git show [options] <object>...";
33
34 static void cmd_log_init(int argc, const char **argv, const char *prefix,
35                       struct rev_info *rev)
36 {
37         int i;
38         int decoration_style = 0;
39
40         rev->abbrev = DEFAULT_ABBREV;
41         rev->commit_format = CMIT_FMT_DEFAULT;
42         if (fmt_pretty)
43                 get_commit_format(fmt_pretty, rev);
44         rev->verbose_header = 1;
45         DIFF_OPT_SET(&rev->diffopt, RECURSIVE);
46         rev->show_root_diff = default_show_root;
47         rev->subject_prefix = fmt_patch_subject_prefix;
48         DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
49
50         if (default_date_mode)
51                 rev->date_mode = parse_date_format(default_date_mode);
52
53         /*
54          * Check for -h before setup_revisions(), or "git log -h" will
55          * fail when run without a git directory.
56          */
57         if (argc == 2 && !strcmp(argv[1], "-h"))
58                 usage(builtin_log_usage);
59         argc = setup_revisions(argc, argv, rev, "HEAD");
60
61         if (!rev->show_notes_given && !rev->pretty_given)
62                 rev->show_notes = 1;
63
64         if (rev->diffopt.pickaxe || rev->diffopt.filter)
65                 rev->always_show_header = 0;
66         if (DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) {
67                 rev->always_show_header = 0;
68                 if (rev->diffopt.nr_paths != 1)
69                         usage("git logs can only follow renames on one pathname at a time");
70         }
71         for (i = 1; i < argc; i++) {
72                 const char *arg = argv[i];
73                 if (!strcmp(arg, "--decorate")) {
74                         decoration_style = DECORATE_SHORT_REFS;
75                 } else if (!prefixcmp(arg, "--decorate=")) {
76                         const char *v = skip_prefix(arg, "--decorate=");
77                         if (!strcmp(v, "full"))
78                                 decoration_style = DECORATE_FULL_REFS;
79                         else if (!strcmp(v, "short"))
80                                 decoration_style = DECORATE_SHORT_REFS;
81                         else
82                                 die("invalid --decorate option: %s", arg);
83                 } else if (!strcmp(arg, "--source")) {
84                         rev->show_source = 1;
85                 } else if (!strcmp(arg, "-h")) {
86                         usage(builtin_log_usage);
87                 } else
88                         die("unrecognized argument: %s", arg);
89         }
90         if (decoration_style) {
91                 rev->show_decorations = 1;
92                 load_ref_decorations(decoration_style);
93         }
94 }
95
96 /*
97  * This gives a rough estimate for how many commits we
98  * will print out in the list.
99  */
100 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
101 {
102         int n = 0;
103
104         while (list) {
105                 struct commit *commit = list->item;
106                 unsigned int flags = commit->object.flags;
107                 list = list->next;
108                 if (!(flags & (TREESAME | UNINTERESTING)))
109                         n++;
110         }
111         return n;
112 }
113
114 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
115 {
116         if (rev->shown_one) {
117                 rev->shown_one = 0;
118                 if (rev->commit_format != CMIT_FMT_ONELINE)
119                         putchar(rev->diffopt.line_termination);
120         }
121         printf("Final output: %d %s\n", nr, stage);
122 }
123
124 static struct itimerval early_output_timer;
125
126 static void log_show_early(struct rev_info *revs, struct commit_list *list)
127 {
128         int i = revs->early_output;
129         int show_header = 1;
130
131         sort_in_topological_order(&list, revs->lifo);
132         while (list && i) {
133                 struct commit *commit = list->item;
134                 switch (simplify_commit(revs, commit)) {
135                 case commit_show:
136                         if (show_header) {
137                                 int n = estimate_commit_count(revs, list);
138                                 show_early_header(revs, "incomplete", n);
139                                 show_header = 0;
140                         }
141                         log_tree_commit(revs, commit);
142                         i--;
143                         break;
144                 case commit_ignore:
145                         break;
146                 case commit_error:
147                         return;
148                 }
149                 list = list->next;
150         }
151
152         /* Did we already get enough commits for the early output? */
153         if (!i)
154                 return;
155
156         /*
157          * ..if no, then repeat it twice a second until we
158          * do.
159          *
160          * NOTE! We don't use "it_interval", because if the
161          * reader isn't listening, we want our output to be
162          * throttled by the writing, and not have the timer
163          * trigger every second even if we're blocked on a
164          * reader!
165          */
166         early_output_timer.it_value.tv_sec = 0;
167         early_output_timer.it_value.tv_usec = 500000;
168         setitimer(ITIMER_REAL, &early_output_timer, NULL);
169 }
170
171 static void early_output(int signal)
172 {
173         show_early_output = log_show_early;
174 }
175
176 static void setup_early_output(struct rev_info *rev)
177 {
178         struct sigaction sa;
179
180         /*
181          * Set up the signal handler, minimally intrusively:
182          * we only set a single volatile integer word (not
183          * using sigatomic_t - trying to avoid unnecessary
184          * system dependencies and headers), and using
185          * SA_RESTART.
186          */
187         memset(&sa, 0, sizeof(sa));
188         sa.sa_handler = early_output;
189         sigemptyset(&sa.sa_mask);
190         sa.sa_flags = SA_RESTART;
191         sigaction(SIGALRM, &sa, NULL);
192
193         /*
194          * If we can get the whole output in less than a
195          * tenth of a second, don't even bother doing the
196          * early-output thing..
197          *
198          * This is a one-time-only trigger.
199          */
200         early_output_timer.it_value.tv_sec = 0;
201         early_output_timer.it_value.tv_usec = 100000;
202         setitimer(ITIMER_REAL, &early_output_timer, NULL);
203 }
204
205 static void finish_early_output(struct rev_info *rev)
206 {
207         int n = estimate_commit_count(rev, rev->commits);
208         signal(SIGALRM, SIG_IGN);
209         show_early_header(rev, "done", n);
210 }
211
212 static int cmd_log_walk(struct rev_info *rev)
213 {
214         struct commit *commit;
215
216         if (rev->early_output)
217                 setup_early_output(rev);
218
219         if (prepare_revision_walk(rev))
220                 die("revision walk setup failed");
221
222         if (rev->early_output)
223                 finish_early_output(rev);
224
225         /*
226          * For --check and --exit-code, the exit code is based on CHECK_FAILED
227          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
228          * retain that state information if replacing rev->diffopt in this loop
229          */
230         while ((commit = get_revision(rev)) != NULL) {
231                 log_tree_commit(rev, commit);
232                 if (!rev->reflog_info) {
233                         /* we allow cycles in reflog ancestry */
234                         free(commit->buffer);
235                         commit->buffer = NULL;
236                 }
237                 free_commit_list(commit->parents);
238                 commit->parents = NULL;
239         }
240         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
241             DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
242                 return 02;
243         }
244         return diff_result_code(&rev->diffopt, 0);
245 }
246
247 static int git_log_config(const char *var, const char *value, void *cb)
248 {
249         if (!strcmp(var, "format.pretty"))
250                 return git_config_string(&fmt_pretty, var, value);
251         if (!strcmp(var, "format.subjectprefix"))
252                 return git_config_string(&fmt_patch_subject_prefix, var, value);
253         if (!strcmp(var, "log.date"))
254                 return git_config_string(&default_date_mode, var, value);
255         if (!strcmp(var, "log.showroot")) {
256                 default_show_root = git_config_bool(var, value);
257                 return 0;
258         }
259         return git_diff_ui_config(var, value, cb);
260 }
261
262 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
263 {
264         struct rev_info rev;
265
266         git_config(git_log_config, NULL);
267
268         if (diff_use_color_default == -1)
269                 diff_use_color_default = git_use_color_default;
270
271         init_revisions(&rev, prefix);
272         rev.diff = 1;
273         rev.simplify_history = 0;
274         cmd_log_init(argc, argv, prefix, &rev);
275         if (!rev.diffopt.output_format)
276                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
277         return cmd_log_walk(&rev);
278 }
279
280 static void show_tagger(char *buf, int len, struct rev_info *rev)
281 {
282         struct strbuf out = STRBUF_INIT;
283
284         pp_user_info("Tagger", rev->commit_format, &out, buf, rev->date_mode,
285                 git_log_output_encoding ?
286                 git_log_output_encoding: git_commit_encoding);
287         printf("%s", out.buf);
288         strbuf_release(&out);
289 }
290
291 static int show_object(const unsigned char *sha1, int show_tag_object,
292         struct rev_info *rev)
293 {
294         unsigned long size;
295         enum object_type type;
296         char *buf = read_sha1_file(sha1, &type, &size);
297         int offset = 0;
298
299         if (!buf)
300                 return error("Could not read object %s", sha1_to_hex(sha1));
301
302         if (show_tag_object)
303                 while (offset < size && buf[offset] != '\n') {
304                         int new_offset = offset + 1;
305                         while (new_offset < size && buf[new_offset++] != '\n')
306                                 ; /* do nothing */
307                         if (!prefixcmp(buf + offset, "tagger "))
308                                 show_tagger(buf + offset + 7,
309                                             new_offset - offset - 7, rev);
310                         offset = new_offset;
311                 }
312
313         if (offset < size)
314                 fwrite(buf + offset, size - offset, 1, stdout);
315         free(buf);
316         return 0;
317 }
318
319 static int show_tree_object(const unsigned char *sha1,
320                 const char *base, int baselen,
321                 const char *pathname, unsigned mode, int stage, void *context)
322 {
323         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
324         return 0;
325 }
326
327 int cmd_show(int argc, const char **argv, const char *prefix)
328 {
329         struct rev_info rev;
330         struct object_array_entry *objects;
331         int i, count, ret = 0;
332
333         git_config(git_log_config, NULL);
334
335         if (diff_use_color_default == -1)
336                 diff_use_color_default = git_use_color_default;
337
338         init_revisions(&rev, prefix);
339         rev.diff = 1;
340         rev.combine_merges = 1;
341         rev.dense_combined_merges = 1;
342         rev.always_show_header = 1;
343         rev.ignore_merges = 0;
344         rev.no_walk = 1;
345         cmd_log_init(argc, argv, prefix, &rev);
346
347         count = rev.pending.nr;
348         objects = rev.pending.objects;
349         for (i = 0; i < count && !ret; i++) {
350                 struct object *o = objects[i].item;
351                 const char *name = objects[i].name;
352                 switch (o->type) {
353                 case OBJ_BLOB:
354                         ret = show_object(o->sha1, 0, NULL);
355                         break;
356                 case OBJ_TAG: {
357                         struct tag *t = (struct tag *)o;
358
359                         if (rev.shown_one)
360                                 putchar('\n');
361                         printf("%stag %s%s\n",
362                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
363                                         t->tag,
364                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
365                         ret = show_object(o->sha1, 1, &rev);
366                         rev.shown_one = 1;
367                         if (ret)
368                                 break;
369                         o = parse_object(t->tagged->sha1);
370                         if (!o)
371                                 ret = error("Could not read object %s",
372                                             sha1_to_hex(t->tagged->sha1));
373                         objects[i].item = o;
374                         i--;
375                         break;
376                 }
377                 case OBJ_TREE:
378                         if (rev.shown_one)
379                                 putchar('\n');
380                         printf("%stree %s%s\n\n",
381                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
382                                         name,
383                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
384                         read_tree_recursive((struct tree *)o, "", 0, 0, NULL,
385                                         show_tree_object, NULL);
386                         rev.shown_one = 1;
387                         break;
388                 case OBJ_COMMIT:
389                         rev.pending.nr = rev.pending.alloc = 0;
390                         rev.pending.objects = NULL;
391                         add_object_array(o, name, &rev.pending);
392                         ret = cmd_log_walk(&rev);
393                         break;
394                 default:
395                         ret = error("Unknown type: %d", o->type);
396                 }
397         }
398         free(objects);
399         return ret;
400 }
401
402 /*
403  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
404  */
405 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
406 {
407         struct rev_info rev;
408
409         git_config(git_log_config, NULL);
410
411         if (diff_use_color_default == -1)
412                 diff_use_color_default = git_use_color_default;
413
414         init_revisions(&rev, prefix);
415         init_reflog_walk(&rev.reflog_info);
416         rev.abbrev_commit = 1;
417         rev.verbose_header = 1;
418         cmd_log_init(argc, argv, prefix, &rev);
419
420         /*
421          * This means that we override whatever commit format the user gave
422          * on the cmd line.  Sad, but cmd_log_init() currently doesn't
423          * allow us to set a different default.
424          */
425         rev.commit_format = CMIT_FMT_ONELINE;
426         rev.use_terminator = 1;
427         rev.always_show_header = 1;
428
429         /*
430          * We get called through "git reflog", so unlike the other log
431          * routines, we need to set up our pager manually..
432          */
433         setup_pager();
434
435         return cmd_log_walk(&rev);
436 }
437
438 int cmd_log(int argc, const char **argv, const char *prefix)
439 {
440         struct rev_info rev;
441
442         git_config(git_log_config, NULL);
443
444         if (diff_use_color_default == -1)
445                 diff_use_color_default = git_use_color_default;
446
447         init_revisions(&rev, prefix);
448         rev.always_show_header = 1;
449         cmd_log_init(argc, argv, prefix, &rev);
450         return cmd_log_walk(&rev);
451 }
452
453 /* format-patch */
454
455 static const char *fmt_patch_suffix = ".patch";
456 static int numbered = 0;
457 static int auto_number = 1;
458
459 static char *default_attach = NULL;
460
461 static struct string_list extra_hdr;
462 static struct string_list extra_to;
463 static struct string_list extra_cc;
464
465 static void add_header(const char *value)
466 {
467         struct string_list_item *item;
468         int len = strlen(value);
469         while (len && value[len - 1] == '\n')
470                 len--;
471
472         if (!strncasecmp(value, "to: ", 4)) {
473                 item = string_list_append(value + 4, &extra_to);
474                 len -= 4;
475         } else if (!strncasecmp(value, "cc: ", 4)) {
476                 item = string_list_append(value + 4, &extra_cc);
477                 len -= 4;
478         } else {
479                 item = string_list_append(value, &extra_hdr);
480         }
481
482         item->string[len] = '\0';
483 }
484
485 #define THREAD_SHALLOW 1
486 #define THREAD_DEEP 2
487 static int thread = 0;
488 static int do_signoff = 0;
489
490 static int git_format_config(const char *var, const char *value, void *cb)
491 {
492         if (!strcmp(var, "format.headers")) {
493                 if (!value)
494                         die("format.headers without value");
495                 add_header(value);
496                 return 0;
497         }
498         if (!strcmp(var, "format.suffix"))
499                 return git_config_string(&fmt_patch_suffix, var, value);
500         if (!strcmp(var, "format.to")) {
501                 if (!value)
502                         return config_error_nonbool(var);
503                 string_list_append(value, &extra_to);
504                 return 0;
505         }
506         if (!strcmp(var, "format.cc")) {
507                 if (!value)
508                         return config_error_nonbool(var);
509                 string_list_append(value, &extra_cc);
510                 return 0;
511         }
512         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
513                 return 0;
514         }
515         if (!strcmp(var, "format.numbered")) {
516                 if (value && !strcasecmp(value, "auto")) {
517                         auto_number = 1;
518                         return 0;
519                 }
520                 numbered = git_config_bool(var, value);
521                 auto_number = auto_number && numbered;
522                 return 0;
523         }
524         if (!strcmp(var, "format.attach")) {
525                 if (value && *value)
526                         default_attach = xstrdup(value);
527                 else
528                         default_attach = xstrdup(git_version_string);
529                 return 0;
530         }
531         if (!strcmp(var, "format.thread")) {
532                 if (value && !strcasecmp(value, "deep")) {
533                         thread = THREAD_DEEP;
534                         return 0;
535                 }
536                 if (value && !strcasecmp(value, "shallow")) {
537                         thread = THREAD_SHALLOW;
538                         return 0;
539                 }
540                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
541                 return 0;
542         }
543         if (!strcmp(var, "format.signoff")) {
544                 do_signoff = git_config_bool(var, value);
545                 return 0;
546         }
547
548         return git_log_config(var, value, cb);
549 }
550
551 static FILE *realstdout = NULL;
552 static const char *output_directory = NULL;
553 static int outdir_offset;
554
555 static int reopen_stdout(struct commit *commit, struct rev_info *rev)
556 {
557         struct strbuf filename = STRBUF_INIT;
558         int suffix_len = strlen(fmt_patch_suffix) + 1;
559
560         if (output_directory) {
561                 strbuf_addstr(&filename, output_directory);
562                 if (filename.len >=
563                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
564                         return error("name of output directory is too long");
565                 if (filename.buf[filename.len - 1] != '/')
566                         strbuf_addch(&filename, '/');
567         }
568
569         get_patch_filename(commit, rev->nr, fmt_patch_suffix, &filename);
570
571         if (!DIFF_OPT_TST(&rev->diffopt, QUICK))
572                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
573
574         if (freopen(filename.buf, "w", stdout) == NULL)
575                 return error("Cannot open patch file %s", filename.buf);
576
577         strbuf_release(&filename);
578         return 0;
579 }
580
581 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix)
582 {
583         struct rev_info check_rev;
584         struct commit *commit;
585         struct object *o1, *o2;
586         unsigned flags1, flags2;
587
588         if (rev->pending.nr != 2)
589                 die("Need exactly one range.");
590
591         o1 = rev->pending.objects[0].item;
592         flags1 = o1->flags;
593         o2 = rev->pending.objects[1].item;
594         flags2 = o2->flags;
595
596         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
597                 die("Not a range.");
598
599         init_patch_ids(ids);
600
601         /* given a range a..b get all patch ids for b..a */
602         init_revisions(&check_rev, prefix);
603         o1->flags ^= UNINTERESTING;
604         o2->flags ^= UNINTERESTING;
605         add_pending_object(&check_rev, o1, "o1");
606         add_pending_object(&check_rev, o2, "o2");
607         if (prepare_revision_walk(&check_rev))
608                 die("revision walk setup failed");
609
610         while ((commit = get_revision(&check_rev)) != NULL) {
611                 /* ignore merges */
612                 if (commit->parents && commit->parents->next)
613                         continue;
614
615                 add_commit_patch_id(commit, ids);
616         }
617
618         /* reset for next revision walk */
619         clear_commit_marks((struct commit *)o1,
620                         SEEN | UNINTERESTING | SHOWN | ADDED);
621         clear_commit_marks((struct commit *)o2,
622                         SEEN | UNINTERESTING | SHOWN | ADDED);
623         o1->flags = flags1;
624         o2->flags = flags2;
625 }
626
627 static void gen_message_id(struct rev_info *info, char *base)
628 {
629         const char *committer = git_committer_info(IDENT_WARN_ON_NO_NAME);
630         const char *email_start = strrchr(committer, '<');
631         const char *email_end = strrchr(committer, '>');
632         struct strbuf buf = STRBUF_INIT;
633         if (!email_start || !email_end || email_start > email_end - 1)
634                 die("Could not extract email from committer identity.");
635         strbuf_addf(&buf, "%s.%lu.git.%.*s", base,
636                     (unsigned long) time(NULL),
637                     (int)(email_end - email_start - 1), email_start + 1);
638         info->message_id = strbuf_detach(&buf, NULL);
639 }
640
641 static void make_cover_letter(struct rev_info *rev, int use_stdout,
642                               int numbered, int numbered_files,
643                               struct commit *origin,
644                               int nr, struct commit **list, struct commit *head)
645 {
646         const char *committer;
647         const char *subject_start = NULL;
648         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
649         const char *msg;
650         const char *extra_headers = rev->extra_headers;
651         struct shortlog log;
652         struct strbuf sb = STRBUF_INIT;
653         int i;
654         const char *encoding = "UTF-8";
655         struct diff_options opts;
656         int need_8bit_cte = 0;
657         struct commit *commit = NULL;
658
659         if (rev->commit_format != CMIT_FMT_EMAIL)
660                 die("Cover letter needs email format");
661
662         committer = git_committer_info(0);
663
664         if (!numbered_files) {
665                 /*
666                  * We fake a commit for the cover letter so we get the filename
667                  * desired.
668                  */
669                 commit = xcalloc(1, sizeof(*commit));
670                 commit->buffer = xmalloc(400);
671                 snprintf(commit->buffer, 400,
672                         "tree 0000000000000000000000000000000000000000\n"
673                         "parent %s\n"
674                         "author %s\n"
675                         "committer %s\n\n"
676                         "cover letter\n",
677                         sha1_to_hex(head->object.sha1), committer, committer);
678         }
679
680         if (!use_stdout && reopen_stdout(commit, rev))
681                 return;
682
683         if (commit) {
684
685                 free(commit->buffer);
686                 free(commit);
687         }
688
689         log_write_email_headers(rev, head, &subject_start, &extra_headers,
690                                 &need_8bit_cte);
691
692         for (i = 0; !need_8bit_cte && i < nr; i++)
693                 if (has_non_ascii(list[i]->buffer))
694                         need_8bit_cte = 1;
695
696         msg = body;
697         pp_user_info(NULL, CMIT_FMT_EMAIL, &sb, committer, DATE_RFC2822,
698                      encoding);
699         pp_title_line(CMIT_FMT_EMAIL, &msg, &sb, subject_start, extra_headers,
700                       encoding, need_8bit_cte);
701         pp_remainder(CMIT_FMT_EMAIL, &msg, &sb, 0);
702         printf("%s\n", sb.buf);
703
704         strbuf_release(&sb);
705
706         shortlog_init(&log);
707         log.wrap_lines = 1;
708         log.wrap = 72;
709         log.in1 = 2;
710         log.in2 = 4;
711         for (i = 0; i < nr; i++)
712                 shortlog_add_commit(&log, list[i]);
713
714         shortlog_output(&log);
715
716         /*
717          * We can only do diffstat with a unique reference point
718          */
719         if (!origin)
720                 return;
721
722         memcpy(&opts, &rev->diffopt, sizeof(opts));
723         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
724
725         diff_setup_done(&opts);
726
727         diff_tree_sha1(origin->tree->object.sha1,
728                        head->tree->object.sha1,
729                        "", &opts);
730         diffcore_std(&opts);
731         diff_flush(&opts);
732
733         printf("\n");
734 }
735
736 static const char *clean_message_id(const char *msg_id)
737 {
738         char ch;
739         const char *a, *z, *m;
740
741         m = msg_id;
742         while ((ch = *m) && (isspace(ch) || (ch == '<')))
743                 m++;
744         a = m;
745         z = NULL;
746         while ((ch = *m)) {
747                 if (!isspace(ch) && (ch != '>'))
748                         z = m;
749                 m++;
750         }
751         if (!z)
752                 die("insane in-reply-to: %s", msg_id);
753         if (++z == m)
754                 return a;
755         return xmemdupz(a, z - a);
756 }
757
758 static const char *set_outdir(const char *prefix, const char *output_directory)
759 {
760         if (output_directory && is_absolute_path(output_directory))
761                 return output_directory;
762
763         if (!prefix || !*prefix) {
764                 if (output_directory)
765                         return output_directory;
766                 /* The user did not explicitly ask for "./" */
767                 outdir_offset = 2;
768                 return "./";
769         }
770
771         outdir_offset = strlen(prefix);
772         if (!output_directory)
773                 return prefix;
774
775         return xstrdup(prefix_filename(prefix, outdir_offset,
776                                        output_directory));
777 }
778
779 static const char * const builtin_format_patch_usage[] = {
780         "git format-patch [options] [<since> | <revision range>]",
781         NULL
782 };
783
784 static int keep_subject = 0;
785
786 static int keep_callback(const struct option *opt, const char *arg, int unset)
787 {
788         ((struct rev_info *)opt->value)->total = -1;
789         keep_subject = 1;
790         return 0;
791 }
792
793 static int subject_prefix = 0;
794
795 static int subject_prefix_callback(const struct option *opt, const char *arg,
796                             int unset)
797 {
798         subject_prefix = 1;
799         ((struct rev_info *)opt->value)->subject_prefix = arg;
800         return 0;
801 }
802
803 static int numbered_cmdline_opt = 0;
804
805 static int numbered_callback(const struct option *opt, const char *arg,
806                              int unset)
807 {
808         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
809         if (unset)
810                 auto_number =  0;
811         return 0;
812 }
813
814 static int no_numbered_callback(const struct option *opt, const char *arg,
815                                 int unset)
816 {
817         return numbered_callback(opt, arg, 1);
818 }
819
820 static int output_directory_callback(const struct option *opt, const char *arg,
821                               int unset)
822 {
823         const char **dir = (const char **)opt->value;
824         if (*dir)
825                 die("Two output directories?");
826         *dir = arg;
827         return 0;
828 }
829
830 static int thread_callback(const struct option *opt, const char *arg, int unset)
831 {
832         int *thread = (int *)opt->value;
833         if (unset)
834                 *thread = 0;
835         else if (!arg || !strcmp(arg, "shallow"))
836                 *thread = THREAD_SHALLOW;
837         else if (!strcmp(arg, "deep"))
838                 *thread = THREAD_DEEP;
839         else
840                 return 1;
841         return 0;
842 }
843
844 static int attach_callback(const struct option *opt, const char *arg, int unset)
845 {
846         struct rev_info *rev = (struct rev_info *)opt->value;
847         if (unset)
848                 rev->mime_boundary = NULL;
849         else if (arg)
850                 rev->mime_boundary = arg;
851         else
852                 rev->mime_boundary = git_version_string;
853         rev->no_inline = unset ? 0 : 1;
854         return 0;
855 }
856
857 static int inline_callback(const struct option *opt, const char *arg, int unset)
858 {
859         struct rev_info *rev = (struct rev_info *)opt->value;
860         if (unset)
861                 rev->mime_boundary = NULL;
862         else if (arg)
863                 rev->mime_boundary = arg;
864         else
865                 rev->mime_boundary = git_version_string;
866         rev->no_inline = 0;
867         return 0;
868 }
869
870 static int header_callback(const struct option *opt, const char *arg, int unset)
871 {
872         if (unset) {
873                 string_list_clear(&extra_hdr, 0);
874                 string_list_clear(&extra_to, 0);
875                 string_list_clear(&extra_cc, 0);
876         } else {
877             add_header(arg);
878         }
879         return 0;
880 }
881
882 static int to_callback(const struct option *opt, const char *arg, int unset)
883 {
884         if (unset)
885                 string_list_clear(&extra_to, 0);
886         else
887                 string_list_append(arg, &extra_to);
888         return 0;
889 }
890
891 static int cc_callback(const struct option *opt, const char *arg, int unset)
892 {
893         if (unset)
894                 string_list_clear(&extra_cc, 0);
895         else
896                 string_list_append(arg, &extra_cc);
897         return 0;
898 }
899
900 int cmd_format_patch(int argc, const char **argv, const char *prefix)
901 {
902         struct commit *commit;
903         struct commit **list = NULL;
904         struct rev_info rev;
905         int nr = 0, total, i;
906         int use_stdout = 0;
907         int start_number = -1;
908         int numbered_files = 0;         /* _just_ numbers */
909         int ignore_if_in_upstream = 0;
910         int cover_letter = 0;
911         int boundary_count = 0;
912         int no_binary_diff = 0;
913         struct commit *origin = NULL, *head = NULL;
914         const char *in_reply_to = NULL;
915         struct patch_ids ids;
916         char *add_signoff = NULL;
917         struct strbuf buf = STRBUF_INIT;
918         int use_patch_format = 0;
919         const struct option builtin_format_patch_options[] = {
920                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
921                             "use [PATCH n/m] even with a single patch",
922                             PARSE_OPT_NOARG, numbered_callback },
923                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
924                             "use [PATCH] even with multiple patches",
925                             PARSE_OPT_NOARG, no_numbered_callback },
926                 OPT_BOOLEAN('s', "signoff", &do_signoff, "add Signed-off-by:"),
927                 OPT_BOOLEAN(0, "stdout", &use_stdout,
928                             "print patches to standard out"),
929                 OPT_BOOLEAN(0, "cover-letter", &cover_letter,
930                             "generate a cover letter"),
931                 OPT_BOOLEAN(0, "numbered-files", &numbered_files,
932                             "use simple number sequence for output file names"),
933                 OPT_STRING(0, "suffix", &fmt_patch_suffix, "sfx",
934                             "use <sfx> instead of '.patch'"),
935                 OPT_INTEGER(0, "start-number", &start_number,
936                             "start numbering patches at <n> instead of 1"),
937                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, "prefix",
938                             "Use [<prefix>] instead of [PATCH]",
939                             PARSE_OPT_NONEG, subject_prefix_callback },
940                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
941                             "dir", "store resulting files in <dir>",
942                             PARSE_OPT_NONEG, output_directory_callback },
943                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
944                             "don't strip/add [PATCH]",
945                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
946                 OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
947                             "don't output binary diffs"),
948                 OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
949                             "don't include a patch matching a commit upstream"),
950                 { OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
951                   "show patch format instead of default (patch + stat)",
952                   PARSE_OPT_NONEG | PARSE_OPT_NOARG },
953                 OPT_GROUP("Messaging"),
954                 { OPTION_CALLBACK, 0, "add-header", NULL, "header",
955                             "add email header", 0, header_callback },
956                 { OPTION_CALLBACK, 0, "to", NULL, "email", "add To: header",
957                             0, to_callback },
958                 { OPTION_CALLBACK, 0, "cc", NULL, "email", "add Cc: header",
959                             0, cc_callback },
960                 OPT_STRING(0, "in-reply-to", &in_reply_to, "message-id",
961                             "make first mail a reply to <message-id>"),
962                 { OPTION_CALLBACK, 0, "attach", &rev, "boundary",
963                             "attach the patch", PARSE_OPT_OPTARG,
964                             attach_callback },
965                 { OPTION_CALLBACK, 0, "inline", &rev, "boundary",
966                             "inline the patch",
967                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
968                             inline_callback },
969                 { OPTION_CALLBACK, 0, "thread", &thread, "style",
970                             "enable message threading, styles: shallow, deep",
971                             PARSE_OPT_OPTARG, thread_callback },
972                 OPT_END()
973         };
974
975         extra_hdr.strdup_strings = 1;
976         extra_to.strdup_strings = 1;
977         extra_cc.strdup_strings = 1;
978         git_config(git_format_config, NULL);
979         init_revisions(&rev, prefix);
980         rev.commit_format = CMIT_FMT_EMAIL;
981         rev.verbose_header = 1;
982         rev.diff = 1;
983         rev.combine_merges = 0;
984         rev.ignore_merges = 1;
985         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
986
987         rev.subject_prefix = fmt_patch_subject_prefix;
988
989         if (default_attach) {
990                 rev.mime_boundary = default_attach;
991                 rev.no_inline = 1;
992         }
993
994         /*
995          * Parse the arguments before setup_revisions(), or something
996          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
997          * possibly a valid SHA1.
998          */
999         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1000                              builtin_format_patch_usage,
1001                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1002                              PARSE_OPT_KEEP_DASHDASH);
1003
1004         if (do_signoff) {
1005                 const char *committer;
1006                 const char *endpos;
1007                 committer = git_committer_info(IDENT_ERROR_ON_NO_NAME);
1008                 endpos = strchr(committer, '>');
1009                 if (!endpos)
1010                         die("bogus committer info %s", committer);
1011                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1012         }
1013
1014         for (i = 0; i < extra_hdr.nr; i++) {
1015                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1016                 strbuf_addch(&buf, '\n');
1017         }
1018
1019         if (extra_to.nr)
1020                 strbuf_addstr(&buf, "To: ");
1021         for (i = 0; i < extra_to.nr; i++) {
1022                 if (i)
1023                         strbuf_addstr(&buf, "    ");
1024                 strbuf_addstr(&buf, extra_to.items[i].string);
1025                 if (i + 1 < extra_to.nr)
1026                         strbuf_addch(&buf, ',');
1027                 strbuf_addch(&buf, '\n');
1028         }
1029
1030         if (extra_cc.nr)
1031                 strbuf_addstr(&buf, "Cc: ");
1032         for (i = 0; i < extra_cc.nr; i++) {
1033                 if (i)
1034                         strbuf_addstr(&buf, "    ");
1035                 strbuf_addstr(&buf, extra_cc.items[i].string);
1036                 if (i + 1 < extra_cc.nr)
1037                         strbuf_addch(&buf, ',');
1038                 strbuf_addch(&buf, '\n');
1039         }
1040
1041         rev.extra_headers = strbuf_detach(&buf, NULL);
1042
1043         if (start_number < 0)
1044                 start_number = 1;
1045
1046         /*
1047          * If numbered is set solely due to format.numbered in config,
1048          * and it would conflict with --keep-subject (-k) from the
1049          * command line, reset "numbered".
1050          */
1051         if (numbered && keep_subject && !numbered_cmdline_opt)
1052                 numbered = 0;
1053
1054         if (numbered && keep_subject)
1055                 die ("-n and -k are mutually exclusive.");
1056         if (keep_subject && subject_prefix)
1057                 die ("--subject-prefix and -k are mutually exclusive.");
1058
1059         argc = setup_revisions(argc, argv, &rev, "HEAD");
1060         if (argc > 1)
1061                 die ("unrecognized argument: %s", argv[1]);
1062
1063         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1064                 die("--name-only does not make sense");
1065         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1066                 die("--name-status does not make sense");
1067         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1068                 die("--check does not make sense");
1069
1070         if (!use_patch_format &&
1071                 (!rev.diffopt.output_format ||
1072                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1073                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1074
1075         /* Always generate a patch */
1076         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1077
1078         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1079                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1080
1081         if (!use_stdout)
1082                 output_directory = set_outdir(prefix, output_directory);
1083
1084         if (output_directory) {
1085                 if (use_stdout)
1086                         die("standard output, or directory, which one?");
1087                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1088                         die_errno("Could not create directory '%s'",
1089                                   output_directory);
1090         }
1091
1092         if (rev.pending.nr == 1) {
1093                 if (rev.max_count < 0 && !rev.show_root_diff) {
1094                         /*
1095                          * This is traditional behaviour of "git format-patch
1096                          * origin" that prepares what the origin side still
1097                          * does not have.
1098                          */
1099                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1100                         add_head_to_pending(&rev);
1101                 }
1102                 /*
1103                  * Otherwise, it is "format-patch -22 HEAD", and/or
1104                  * "format-patch --root HEAD".  The user wants
1105                  * get_revision() to do the usual traversal.
1106                  */
1107         }
1108
1109         /*
1110          * We cannot move this anywhere earlier because we do want to
1111          * know if --root was given explicitly from the command line.
1112          */
1113         rev.show_root_diff = 1;
1114
1115         if (cover_letter) {
1116                 /* remember the range */
1117                 int i;
1118                 for (i = 0; i < rev.pending.nr; i++) {
1119                         struct object *o = rev.pending.objects[i].item;
1120                         if (!(o->flags & UNINTERESTING))
1121                                 head = (struct commit *)o;
1122                 }
1123                 /* We can't generate a cover letter without any patches */
1124                 if (!head)
1125                         return 0;
1126         }
1127
1128         if (ignore_if_in_upstream)
1129                 get_patch_ids(&rev, &ids, prefix);
1130
1131         if (!use_stdout)
1132                 realstdout = xfdopen(xdup(1), "w");
1133
1134         if (prepare_revision_walk(&rev))
1135                 die("revision walk setup failed");
1136         rev.boundary = 1;
1137         while ((commit = get_revision(&rev)) != NULL) {
1138                 if (commit->object.flags & BOUNDARY) {
1139                         boundary_count++;
1140                         origin = (boundary_count == 1) ? commit : NULL;
1141                         continue;
1142                 }
1143
1144                 /* ignore merges */
1145                 if (commit->parents && commit->parents->next)
1146                         continue;
1147
1148                 if (ignore_if_in_upstream &&
1149                                 has_commit_patch_id(commit, &ids))
1150                         continue;
1151
1152                 nr++;
1153                 list = xrealloc(list, nr * sizeof(list[0]));
1154                 list[nr - 1] = commit;
1155         }
1156         total = nr;
1157         if (!keep_subject && auto_number && total > 1)
1158                 numbered = 1;
1159         if (numbered)
1160                 rev.total = total + start_number - 1;
1161         if (in_reply_to || thread || cover_letter)
1162                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1163         if (in_reply_to) {
1164                 const char *msgid = clean_message_id(in_reply_to);
1165                 string_list_append(msgid, rev.ref_message_ids);
1166         }
1167         rev.numbered_files = numbered_files;
1168         rev.patch_suffix = fmt_patch_suffix;
1169         if (cover_letter) {
1170                 if (thread)
1171                         gen_message_id(&rev, "cover");
1172                 make_cover_letter(&rev, use_stdout, numbered, numbered_files,
1173                                   origin, nr, list, head);
1174                 total++;
1175                 start_number--;
1176         }
1177         rev.add_signoff = add_signoff;
1178         while (0 <= --nr) {
1179                 int shown;
1180                 commit = list[nr];
1181                 rev.nr = total - nr + (start_number - 1);
1182                 /* Make the second and subsequent mails replies to the first */
1183                 if (thread) {
1184                         /* Have we already had a message ID? */
1185                         if (rev.message_id) {
1186                                 /*
1187                                  * For deep threading: make every mail
1188                                  * a reply to the previous one, no
1189                                  * matter what other options are set.
1190                                  *
1191                                  * For shallow threading:
1192                                  *
1193                                  * Without --cover-letter and
1194                                  * --in-reply-to, make every mail a
1195                                  * reply to the one before.
1196                                  *
1197                                  * With --in-reply-to but no
1198                                  * --cover-letter, make every mail a
1199                                  * reply to the <reply-to>.
1200                                  *
1201                                  * With --cover-letter, make every
1202                                  * mail but the cover letter a reply
1203                                  * to the cover letter.  The cover
1204                                  * letter is a reply to the
1205                                  * --in-reply-to, if specified.
1206                                  */
1207                                 if (thread == THREAD_SHALLOW
1208                                     && rev.ref_message_ids->nr > 0
1209                                     && (!cover_letter || rev.nr > 1))
1210                                         free(rev.message_id);
1211                                 else
1212                                         string_list_append(rev.message_id,
1213                                                            rev.ref_message_ids);
1214                         }
1215                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1216                 }
1217
1218                 if (!use_stdout && reopen_stdout(numbered_files ? NULL : commit,
1219                                                  &rev))
1220                         die("Failed to create output files");
1221                 shown = log_tree_commit(&rev, commit);
1222                 free(commit->buffer);
1223                 commit->buffer = NULL;
1224
1225                 /* We put one extra blank line between formatted
1226                  * patches and this flag is used by log-tree code
1227                  * to see if it needs to emit a LF before showing
1228                  * the log; when using one file per patch, we do
1229                  * not want the extra blank line.
1230                  */
1231                 if (!use_stdout)
1232                         rev.shown_one = 0;
1233                 if (shown) {
1234                         if (rev.mime_boundary)
1235                                 printf("\n--%s%s--\n\n\n",
1236                                        mime_boundary_leader,
1237                                        rev.mime_boundary);
1238                         else
1239                                 printf("-- \n%s\n\n", git_version_string);
1240                 }
1241                 if (!use_stdout)
1242                         fclose(stdout);
1243         }
1244         free(list);
1245         string_list_clear(&extra_to, 0);
1246         string_list_clear(&extra_cc, 0);
1247         string_list_clear(&extra_hdr, 0);
1248         if (ignore_if_in_upstream)
1249                 free_patch_ids(&ids);
1250         return 0;
1251 }
1252
1253 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1254 {
1255         unsigned char sha1[20];
1256         if (get_sha1(arg, sha1) == 0) {
1257                 struct commit *commit = lookup_commit_reference(sha1);
1258                 if (commit) {
1259                         commit->object.flags |= flags;
1260                         add_pending_object(revs, &commit->object, arg);
1261                         return 0;
1262                 }
1263         }
1264         return -1;
1265 }
1266
1267 static const char cherry_usage[] =
1268 "git cherry [-v] [<upstream> [<head> [<limit>]]]";
1269 int cmd_cherry(int argc, const char **argv, const char *prefix)
1270 {
1271         struct rev_info revs;
1272         struct patch_ids ids;
1273         struct commit *commit;
1274         struct commit_list *list = NULL;
1275         struct branch *current_branch;
1276         const char *upstream;
1277         const char *head = "HEAD";
1278         const char *limit = NULL;
1279         int verbose = 0;
1280
1281         if (argc > 1 && !strcmp(argv[1], "-v")) {
1282                 verbose = 1;
1283                 argc--;
1284                 argv++;
1285         }
1286
1287         if (argc > 1 && !strcmp(argv[1], "-h"))
1288                 usage(cherry_usage);
1289
1290         switch (argc) {
1291         case 4:
1292                 limit = argv[3];
1293                 /* FALLTHROUGH */
1294         case 3:
1295                 head = argv[2];
1296                 /* FALLTHROUGH */
1297         case 2:
1298                 upstream = argv[1];
1299                 break;
1300         default:
1301                 current_branch = branch_get(NULL);
1302                 if (!current_branch || !current_branch->merge
1303                                         || !current_branch->merge[0]
1304                                         || !current_branch->merge[0]->dst) {
1305                         fprintf(stderr, "Could not find a tracked"
1306                                         " remote branch, please"
1307                                         " specify <upstream> manually.\n");
1308                         usage(cherry_usage);
1309                 }
1310
1311                 upstream = current_branch->merge[0]->dst;
1312         }
1313
1314         init_revisions(&revs, prefix);
1315         revs.diff = 1;
1316         revs.combine_merges = 0;
1317         revs.ignore_merges = 1;
1318         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1319
1320         if (add_pending_commit(head, &revs, 0))
1321                 die("Unknown commit %s", head);
1322         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1323                 die("Unknown commit %s", upstream);
1324
1325         /* Don't say anything if head and upstream are the same. */
1326         if (revs.pending.nr == 2) {
1327                 struct object_array_entry *o = revs.pending.objects;
1328                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1329                         return 0;
1330         }
1331
1332         get_patch_ids(&revs, &ids, prefix);
1333
1334         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1335                 die("Unknown commit %s", limit);
1336
1337         /* reverse the list of commits */
1338         if (prepare_revision_walk(&revs))
1339                 die("revision walk setup failed");
1340         while ((commit = get_revision(&revs)) != NULL) {
1341                 /* ignore merges */
1342                 if (commit->parents && commit->parents->next)
1343                         continue;
1344
1345                 commit_list_insert(commit, &list);
1346         }
1347
1348         while (list) {
1349                 char sign = '+';
1350
1351                 commit = list->item;
1352                 if (has_commit_patch_id(commit, &ids))
1353                         sign = '-';
1354
1355                 if (verbose) {
1356                         struct strbuf buf = STRBUF_INIT;
1357                         struct pretty_print_context ctx = {0};
1358                         pretty_print_commit(CMIT_FMT_ONELINE, commit,
1359                                             &buf, &ctx);
1360                         printf("%c %s %s\n", sign,
1361                                sha1_to_hex(commit->object.sha1), buf.buf);
1362                         strbuf_release(&buf);
1363                 }
1364                 else {
1365                         printf("%c %s\n", sign,
1366                                sha1_to_hex(commit->object.sha1));
1367                 }
1368
1369                 list = list->next;
1370         }
1371
1372         free_patch_ids(&ids);
1373         return 0;
1374 }