Merge branch 'dt/refs-pseudo'
[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 "refs.h"
9 #include "color.h"
10 #include "commit.h"
11 #include "diff.h"
12 #include "revision.h"
13 #include "log-tree.h"
14 #include "builtin.h"
15 #include "tag.h"
16 #include "reflog-walk.h"
17 #include "patch-ids.h"
18 #include "run-command.h"
19 #include "shortlog.h"
20 #include "remote.h"
21 #include "string-list.h"
22 #include "parse-options.h"
23 #include "line-log.h"
24 #include "branch.h"
25 #include "streaming.h"
26 #include "version.h"
27 #include "mailmap.h"
28 #include "gpg-interface.h"
29
30 /* Set a default date-time format for git log ("log.date" config variable) */
31 static const char *default_date_mode = NULL;
32
33 static int default_abbrev_commit;
34 static int default_show_root = 1;
35 static int default_follow;
36 static int decoration_style;
37 static int decoration_given;
38 static int use_mailmap_config;
39 static const char *fmt_patch_subject_prefix = "PATCH";
40 static const char *fmt_pretty;
41
42 static const char * const builtin_log_usage[] = {
43         N_("git log [<options>] [<revision-range>] [[--] <path>...]"),
44         N_("git show [<options>] <object>..."),
45         NULL
46 };
47
48 struct line_opt_callback_data {
49         struct rev_info *rev;
50         const char *prefix;
51         struct string_list args;
52 };
53
54 static int parse_decoration_style(const char *var, const char *value)
55 {
56         switch (git_config_maybe_bool(var, value)) {
57         case 1:
58                 return DECORATE_SHORT_REFS;
59         case 0:
60                 return 0;
61         default:
62                 break;
63         }
64         if (!strcmp(value, "full"))
65                 return DECORATE_FULL_REFS;
66         else if (!strcmp(value, "short"))
67                 return DECORATE_SHORT_REFS;
68         else if (!strcmp(value, "auto"))
69                 return (isatty(1) || pager_in_use()) ? DECORATE_SHORT_REFS : 0;
70         return -1;
71 }
72
73 static int decorate_callback(const struct option *opt, const char *arg, int unset)
74 {
75         if (unset)
76                 decoration_style = 0;
77         else if (arg)
78                 decoration_style = parse_decoration_style("command line", arg);
79         else
80                 decoration_style = DECORATE_SHORT_REFS;
81
82         if (decoration_style < 0)
83                 die(_("invalid --decorate option: %s"), arg);
84
85         decoration_given = 1;
86
87         return 0;
88 }
89
90 static int log_line_range_callback(const struct option *option, const char *arg, int unset)
91 {
92         struct line_opt_callback_data *data = option->value;
93
94         if (!arg)
95                 return -1;
96
97         data->rev->line_level_traverse = 1;
98         string_list_append(&data->args, arg);
99
100         return 0;
101 }
102
103 static void cmd_log_init_defaults(struct rev_info *rev)
104 {
105         if (fmt_pretty)
106                 get_commit_format(fmt_pretty, rev);
107         if (default_follow)
108                 DIFF_OPT_SET(&rev->diffopt, DEFAULT_FOLLOW_RENAMES);
109         rev->verbose_header = 1;
110         DIFF_OPT_SET(&rev->diffopt, RECURSIVE);
111         rev->diffopt.stat_width = -1; /* use full terminal width */
112         rev->diffopt.stat_graph_width = -1; /* respect statGraphWidth config */
113         rev->abbrev_commit = default_abbrev_commit;
114         rev->show_root_diff = default_show_root;
115         rev->subject_prefix = fmt_patch_subject_prefix;
116         DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
117
118         if (default_date_mode)
119                 parse_date_format(default_date_mode, &rev->date_mode);
120         rev->diffopt.touched_flags = 0;
121 }
122
123 static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
124                          struct rev_info *rev, struct setup_revision_opt *opt)
125 {
126         struct userformat_want w;
127         int quiet = 0, source = 0, mailmap = 0;
128         static struct line_opt_callback_data line_cb = {NULL, NULL, STRING_LIST_INIT_DUP};
129
130         const struct option builtin_log_options[] = {
131                 OPT__QUIET(&quiet, N_("suppress diff output")),
132                 OPT_BOOL(0, "source", &source, N_("show source")),
133                 OPT_BOOL(0, "use-mailmap", &mailmap, N_("Use mail map file")),
134                 { OPTION_CALLBACK, 0, "decorate", NULL, NULL, N_("decorate options"),
135                   PARSE_OPT_OPTARG, decorate_callback},
136                 OPT_CALLBACK('L', NULL, &line_cb, "n,m:file",
137                              N_("Process line range n,m in file, counting from 1"),
138                              log_line_range_callback),
139                 OPT_END()
140         };
141
142         line_cb.rev = rev;
143         line_cb.prefix = prefix;
144
145         mailmap = use_mailmap_config;
146         argc = parse_options(argc, argv, prefix,
147                              builtin_log_options, builtin_log_usage,
148                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
149                              PARSE_OPT_KEEP_DASHDASH);
150
151         if (quiet)
152                 rev->diffopt.output_format |= DIFF_FORMAT_NO_OUTPUT;
153         argc = setup_revisions(argc, argv, rev, opt);
154
155         /* Any arguments at this point are not recognized */
156         if (argc > 1)
157                 die(_("unrecognized argument: %s"), argv[1]);
158
159         memset(&w, 0, sizeof(w));
160         userformat_find_requirements(NULL, &w);
161
162         if (!rev->show_notes_given && (!rev->pretty_given || w.notes))
163                 rev->show_notes = 1;
164         if (rev->show_notes)
165                 init_display_notes(&rev->notes_opt);
166
167         if (rev->diffopt.pickaxe || rev->diffopt.filter ||
168             DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES))
169                 rev->always_show_header = 0;
170
171         if (source)
172                 rev->show_source = 1;
173
174         if (mailmap) {
175                 rev->mailmap = xcalloc(1, sizeof(struct string_list));
176                 read_mailmap(rev->mailmap, NULL);
177         }
178
179         if (rev->pretty_given && rev->commit_format == CMIT_FMT_RAW) {
180                 /*
181                  * "log --pretty=raw" is special; ignore UI oriented
182                  * configuration variables such as decoration.
183                  */
184                 if (!decoration_given)
185                         decoration_style = 0;
186                 if (!rev->abbrev_commit_given)
187                         rev->abbrev_commit = 0;
188         }
189
190         if (decoration_style) {
191                 rev->show_decorations = 1;
192                 load_ref_decorations(decoration_style);
193         }
194
195         if (rev->line_level_traverse)
196                 line_log_init(rev, line_cb.prefix, &line_cb.args);
197
198         setup_pager();
199 }
200
201 static void cmd_log_init(int argc, const char **argv, const char *prefix,
202                          struct rev_info *rev, struct setup_revision_opt *opt)
203 {
204         cmd_log_init_defaults(rev);
205         cmd_log_init_finish(argc, argv, prefix, rev, opt);
206 }
207
208 /*
209  * This gives a rough estimate for how many commits we
210  * will print out in the list.
211  */
212 static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
213 {
214         int n = 0;
215
216         while (list) {
217                 struct commit *commit = list->item;
218                 unsigned int flags = commit->object.flags;
219                 list = list->next;
220                 if (!(flags & (TREESAME | UNINTERESTING)))
221                         n++;
222         }
223         return n;
224 }
225
226 static void show_early_header(struct rev_info *rev, const char *stage, int nr)
227 {
228         if (rev->shown_one) {
229                 rev->shown_one = 0;
230                 if (rev->commit_format != CMIT_FMT_ONELINE)
231                         putchar(rev->diffopt.line_termination);
232         }
233         printf(_("Final output: %d %s\n"), nr, stage);
234 }
235
236 static struct itimerval early_output_timer;
237
238 static void log_show_early(struct rev_info *revs, struct commit_list *list)
239 {
240         int i = revs->early_output;
241         int show_header = 1;
242
243         sort_in_topological_order(&list, revs->sort_order);
244         while (list && i) {
245                 struct commit *commit = list->item;
246                 switch (simplify_commit(revs, commit)) {
247                 case commit_show:
248                         if (show_header) {
249                                 int n = estimate_commit_count(revs, list);
250                                 show_early_header(revs, "incomplete", n);
251                                 show_header = 0;
252                         }
253                         log_tree_commit(revs, commit);
254                         i--;
255                         break;
256                 case commit_ignore:
257                         break;
258                 case commit_error:
259                         return;
260                 }
261                 list = list->next;
262         }
263
264         /* Did we already get enough commits for the early output? */
265         if (!i)
266                 return;
267
268         /*
269          * ..if no, then repeat it twice a second until we
270          * do.
271          *
272          * NOTE! We don't use "it_interval", because if the
273          * reader isn't listening, we want our output to be
274          * throttled by the writing, and not have the timer
275          * trigger every second even if we're blocked on a
276          * reader!
277          */
278         early_output_timer.it_value.tv_sec = 0;
279         early_output_timer.it_value.tv_usec = 500000;
280         setitimer(ITIMER_REAL, &early_output_timer, NULL);
281 }
282
283 static void early_output(int signal)
284 {
285         show_early_output = log_show_early;
286 }
287
288 static void setup_early_output(struct rev_info *rev)
289 {
290         struct sigaction sa;
291
292         /*
293          * Set up the signal handler, minimally intrusively:
294          * we only set a single volatile integer word (not
295          * using sigatomic_t - trying to avoid unnecessary
296          * system dependencies and headers), and using
297          * SA_RESTART.
298          */
299         memset(&sa, 0, sizeof(sa));
300         sa.sa_handler = early_output;
301         sigemptyset(&sa.sa_mask);
302         sa.sa_flags = SA_RESTART;
303         sigaction(SIGALRM, &sa, NULL);
304
305         /*
306          * If we can get the whole output in less than a
307          * tenth of a second, don't even bother doing the
308          * early-output thing..
309          *
310          * This is a one-time-only trigger.
311          */
312         early_output_timer.it_value.tv_sec = 0;
313         early_output_timer.it_value.tv_usec = 100000;
314         setitimer(ITIMER_REAL, &early_output_timer, NULL);
315 }
316
317 static void finish_early_output(struct rev_info *rev)
318 {
319         int n = estimate_commit_count(rev, rev->commits);
320         signal(SIGALRM, SIG_IGN);
321         show_early_header(rev, "done", n);
322 }
323
324 static int cmd_log_walk(struct rev_info *rev)
325 {
326         struct commit *commit;
327         int saved_nrl = 0;
328         int saved_dcctc = 0;
329
330         if (rev->early_output)
331                 setup_early_output(rev);
332
333         if (prepare_revision_walk(rev))
334                 die(_("revision walk setup failed"));
335
336         if (rev->early_output)
337                 finish_early_output(rev);
338
339         /*
340          * For --check and --exit-code, the exit code is based on CHECK_FAILED
341          * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
342          * retain that state information if replacing rev->diffopt in this loop
343          */
344         while ((commit = get_revision(rev)) != NULL) {
345                 if (!log_tree_commit(rev, commit) &&
346                     rev->max_count >= 0)
347                         /*
348                          * We decremented max_count in get_revision,
349                          * but we didn't actually show the commit.
350                          */
351                         rev->max_count++;
352                 if (!rev->reflog_info) {
353                         /* we allow cycles in reflog ancestry */
354                         free_commit_buffer(commit);
355                 }
356                 free_commit_list(commit->parents);
357                 commit->parents = NULL;
358                 if (saved_nrl < rev->diffopt.needed_rename_limit)
359                         saved_nrl = rev->diffopt.needed_rename_limit;
360                 if (rev->diffopt.degraded_cc_to_c)
361                         saved_dcctc = 1;
362         }
363         rev->diffopt.degraded_cc_to_c = saved_dcctc;
364         rev->diffopt.needed_rename_limit = saved_nrl;
365
366         if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
367             DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
368                 return 02;
369         }
370         return diff_result_code(&rev->diffopt, 0);
371 }
372
373 static int git_log_config(const char *var, const char *value, void *cb)
374 {
375         const char *slot_name;
376
377         if (!strcmp(var, "format.pretty"))
378                 return git_config_string(&fmt_pretty, var, value);
379         if (!strcmp(var, "format.subjectprefix"))
380                 return git_config_string(&fmt_patch_subject_prefix, var, value);
381         if (!strcmp(var, "log.abbrevcommit")) {
382                 default_abbrev_commit = git_config_bool(var, value);
383                 return 0;
384         }
385         if (!strcmp(var, "log.date"))
386                 return git_config_string(&default_date_mode, var, value);
387         if (!strcmp(var, "log.decorate")) {
388                 decoration_style = parse_decoration_style(var, value);
389                 if (decoration_style < 0)
390                         decoration_style = 0; /* maybe warn? */
391                 return 0;
392         }
393         if (!strcmp(var, "log.showroot")) {
394                 default_show_root = git_config_bool(var, value);
395                 return 0;
396         }
397         if (!strcmp(var, "log.follow")) {
398                 default_follow = git_config_bool(var, value);
399                 return 0;
400         }
401         if (skip_prefix(var, "color.decorate.", &slot_name))
402                 return parse_decorate_color_config(var, slot_name, value);
403         if (!strcmp(var, "log.mailmap")) {
404                 use_mailmap_config = git_config_bool(var, value);
405                 return 0;
406         }
407
408         if (grep_config(var, value, cb) < 0)
409                 return -1;
410         if (git_gpg_config(var, value, cb) < 0)
411                 return -1;
412         return git_diff_ui_config(var, value, cb);
413 }
414
415 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
416 {
417         struct rev_info rev;
418         struct setup_revision_opt opt;
419
420         init_grep_defaults();
421         git_config(git_log_config, NULL);
422
423         init_revisions(&rev, prefix);
424         rev.diff = 1;
425         rev.simplify_history = 0;
426         memset(&opt, 0, sizeof(opt));
427         opt.def = "HEAD";
428         opt.revarg_opt = REVARG_COMMITTISH;
429         cmd_log_init(argc, argv, prefix, &rev, &opt);
430         if (!rev.diffopt.output_format)
431                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
432         return cmd_log_walk(&rev);
433 }
434
435 static void show_tagger(char *buf, int len, struct rev_info *rev)
436 {
437         struct strbuf out = STRBUF_INIT;
438         struct pretty_print_context pp = {0};
439
440         pp.fmt = rev->commit_format;
441         pp.date_mode = rev->date_mode;
442         pp_user_info(&pp, "Tagger", &out, buf, get_log_output_encoding());
443         printf("%s", out.buf);
444         strbuf_release(&out);
445 }
446
447 static int show_blob_object(const unsigned char *sha1, struct rev_info *rev, const char *obj_name)
448 {
449         unsigned char sha1c[20];
450         struct object_context obj_context;
451         char *buf;
452         unsigned long size;
453
454         fflush(stdout);
455         if (!DIFF_OPT_TOUCHED(&rev->diffopt, ALLOW_TEXTCONV) ||
456             !DIFF_OPT_TST(&rev->diffopt, ALLOW_TEXTCONV))
457                 return stream_blob_to_fd(1, sha1, NULL, 0);
458
459         if (get_sha1_with_context(obj_name, 0, sha1c, &obj_context))
460                 die(_("Not a valid object name %s"), obj_name);
461         if (!obj_context.path[0] ||
462             !textconv_object(obj_context.path, obj_context.mode, sha1c, 1, &buf, &size))
463                 return stream_blob_to_fd(1, sha1, NULL, 0);
464
465         if (!buf)
466                 die(_("git show %s: bad file"), obj_name);
467
468         write_or_die(1, buf, size);
469         return 0;
470 }
471
472 static int show_tag_object(const unsigned char *sha1, struct rev_info *rev)
473 {
474         unsigned long size;
475         enum object_type type;
476         char *buf = read_sha1_file(sha1, &type, &size);
477         int offset = 0;
478
479         if (!buf)
480                 return error(_("Could not read object %s"), sha1_to_hex(sha1));
481
482         assert(type == OBJ_TAG);
483         while (offset < size && buf[offset] != '\n') {
484                 int new_offset = offset + 1;
485                 while (new_offset < size && buf[new_offset++] != '\n')
486                         ; /* do nothing */
487                 if (starts_with(buf + offset, "tagger "))
488                         show_tagger(buf + offset + 7,
489                                     new_offset - offset - 7, rev);
490                 offset = new_offset;
491         }
492
493         if (offset < size)
494                 fwrite(buf + offset, size - offset, 1, stdout);
495         free(buf);
496         return 0;
497 }
498
499 static int show_tree_object(const unsigned char *sha1,
500                 struct strbuf *base,
501                 const char *pathname, unsigned mode, int stage, void *context)
502 {
503         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
504         return 0;
505 }
506
507 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
508 {
509         if (rev->ignore_merges) {
510                 /* There was no "-m" on the command line */
511                 rev->ignore_merges = 0;
512                 if (!rev->first_parent_only && !rev->combine_merges) {
513                         /* No "--first-parent", "-c", or "--cc" */
514                         rev->combine_merges = 1;
515                         rev->dense_combined_merges = 1;
516                 }
517         }
518         if (!rev->diffopt.output_format)
519                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
520 }
521
522 int cmd_show(int argc, const char **argv, const char *prefix)
523 {
524         struct rev_info rev;
525         struct object_array_entry *objects;
526         struct setup_revision_opt opt;
527         struct pathspec match_all;
528         int i, count, ret = 0;
529
530         init_grep_defaults();
531         git_config(git_log_config, NULL);
532
533         memset(&match_all, 0, sizeof(match_all));
534         init_revisions(&rev, prefix);
535         rev.diff = 1;
536         rev.always_show_header = 1;
537         rev.no_walk = REVISION_WALK_NO_WALK_SORTED;
538         rev.diffopt.stat_width = -1;    /* Scale to real terminal size */
539
540         memset(&opt, 0, sizeof(opt));
541         opt.def = "HEAD";
542         opt.tweak = show_rev_tweak_rev;
543         cmd_log_init(argc, argv, prefix, &rev, &opt);
544
545         if (!rev.no_walk)
546                 return cmd_log_walk(&rev);
547
548         count = rev.pending.nr;
549         objects = rev.pending.objects;
550         for (i = 0; i < count && !ret; i++) {
551                 struct object *o = objects[i].item;
552                 const char *name = objects[i].name;
553                 switch (o->type) {
554                 case OBJ_BLOB:
555                         ret = show_blob_object(o->sha1, &rev, name);
556                         break;
557                 case OBJ_TAG: {
558                         struct tag *t = (struct tag *)o;
559
560                         if (rev.shown_one)
561                                 putchar('\n');
562                         printf("%stag %s%s\n",
563                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
564                                         t->tag,
565                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
566                         ret = show_tag_object(o->sha1, &rev);
567                         rev.shown_one = 1;
568                         if (ret)
569                                 break;
570                         o = parse_object(t->tagged->sha1);
571                         if (!o)
572                                 ret = error(_("Could not read object %s"),
573                                             sha1_to_hex(t->tagged->sha1));
574                         objects[i].item = o;
575                         i--;
576                         break;
577                 }
578                 case OBJ_TREE:
579                         if (rev.shown_one)
580                                 putchar('\n');
581                         printf("%stree %s%s\n\n",
582                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
583                                         name,
584                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
585                         read_tree_recursive((struct tree *)o, "", 0, 0, &match_all,
586                                         show_tree_object, NULL);
587                         rev.shown_one = 1;
588                         break;
589                 case OBJ_COMMIT:
590                         rev.pending.nr = rev.pending.alloc = 0;
591                         rev.pending.objects = NULL;
592                         add_object_array(o, name, &rev.pending);
593                         ret = cmd_log_walk(&rev);
594                         break;
595                 default:
596                         ret = error(_("Unknown type: %d"), o->type);
597                 }
598         }
599         free(objects);
600         return ret;
601 }
602
603 /*
604  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
605  */
606 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
607 {
608         struct rev_info rev;
609         struct setup_revision_opt opt;
610
611         init_grep_defaults();
612         git_config(git_log_config, NULL);
613
614         init_revisions(&rev, prefix);
615         init_reflog_walk(&rev.reflog_info);
616         rev.verbose_header = 1;
617         memset(&opt, 0, sizeof(opt));
618         opt.def = "HEAD";
619         cmd_log_init_defaults(&rev);
620         rev.abbrev_commit = 1;
621         rev.commit_format = CMIT_FMT_ONELINE;
622         rev.use_terminator = 1;
623         rev.always_show_header = 1;
624         cmd_log_init_finish(argc, argv, prefix, &rev, &opt);
625
626         return cmd_log_walk(&rev);
627 }
628
629 static void default_follow_tweak(struct rev_info *rev,
630                                  struct setup_revision_opt *opt)
631 {
632         if (DIFF_OPT_TST(&rev->diffopt, DEFAULT_FOLLOW_RENAMES) &&
633             rev->prune_data.nr == 1)
634                 DIFF_OPT_SET(&rev->diffopt, FOLLOW_RENAMES);
635 }
636
637 int cmd_log(int argc, const char **argv, const char *prefix)
638 {
639         struct rev_info rev;
640         struct setup_revision_opt opt;
641
642         init_grep_defaults();
643         git_config(git_log_config, NULL);
644
645         init_revisions(&rev, prefix);
646         rev.always_show_header = 1;
647         memset(&opt, 0, sizeof(opt));
648         opt.def = "HEAD";
649         opt.revarg_opt = REVARG_COMMITTISH;
650         opt.tweak = default_follow_tweak;
651         cmd_log_init(argc, argv, prefix, &rev, &opt);
652         return cmd_log_walk(&rev);
653 }
654
655 /* format-patch */
656
657 static const char *fmt_patch_suffix = ".patch";
658 static int numbered = 0;
659 static int auto_number = 1;
660
661 static char *default_attach = NULL;
662
663 static struct string_list extra_hdr;
664 static struct string_list extra_to;
665 static struct string_list extra_cc;
666
667 static void add_header(const char *value)
668 {
669         struct string_list_item *item;
670         int len = strlen(value);
671         while (len && value[len - 1] == '\n')
672                 len--;
673
674         if (!strncasecmp(value, "to: ", 4)) {
675                 item = string_list_append(&extra_to, value + 4);
676                 len -= 4;
677         } else if (!strncasecmp(value, "cc: ", 4)) {
678                 item = string_list_append(&extra_cc, value + 4);
679                 len -= 4;
680         } else {
681                 item = string_list_append(&extra_hdr, value);
682         }
683
684         item->string[len] = '\0';
685 }
686
687 #define THREAD_SHALLOW 1
688 #define THREAD_DEEP 2
689 static int thread;
690 static int do_signoff;
691 static const char *signature = git_version_string;
692 static const char *signature_file;
693 static int config_cover_letter;
694
695 enum {
696         COVER_UNSET,
697         COVER_OFF,
698         COVER_ON,
699         COVER_AUTO
700 };
701
702 static int git_format_config(const char *var, const char *value, void *cb)
703 {
704         if (!strcmp(var, "format.headers")) {
705                 if (!value)
706                         die(_("format.headers without value"));
707                 add_header(value);
708                 return 0;
709         }
710         if (!strcmp(var, "format.suffix"))
711                 return git_config_string(&fmt_patch_suffix, var, value);
712         if (!strcmp(var, "format.to")) {
713                 if (!value)
714                         return config_error_nonbool(var);
715                 string_list_append(&extra_to, value);
716                 return 0;
717         }
718         if (!strcmp(var, "format.cc")) {
719                 if (!value)
720                         return config_error_nonbool(var);
721                 string_list_append(&extra_cc, value);
722                 return 0;
723         }
724         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff") ||
725             !strcmp(var, "color.ui") || !strcmp(var, "diff.submodule")) {
726                 return 0;
727         }
728         if (!strcmp(var, "format.numbered")) {
729                 if (value && !strcasecmp(value, "auto")) {
730                         auto_number = 1;
731                         return 0;
732                 }
733                 numbered = git_config_bool(var, value);
734                 auto_number = auto_number && numbered;
735                 return 0;
736         }
737         if (!strcmp(var, "format.attach")) {
738                 if (value && *value)
739                         default_attach = xstrdup(value);
740                 else
741                         default_attach = xstrdup(git_version_string);
742                 return 0;
743         }
744         if (!strcmp(var, "format.thread")) {
745                 if (value && !strcasecmp(value, "deep")) {
746                         thread = THREAD_DEEP;
747                         return 0;
748                 }
749                 if (value && !strcasecmp(value, "shallow")) {
750                         thread = THREAD_SHALLOW;
751                         return 0;
752                 }
753                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
754                 return 0;
755         }
756         if (!strcmp(var, "format.signoff")) {
757                 do_signoff = git_config_bool(var, value);
758                 return 0;
759         }
760         if (!strcmp(var, "format.signature"))
761                 return git_config_string(&signature, var, value);
762         if (!strcmp(var, "format.signaturefile"))
763                 return git_config_pathname(&signature_file, var, value);
764         if (!strcmp(var, "format.coverletter")) {
765                 if (value && !strcasecmp(value, "auto")) {
766                         config_cover_letter = COVER_AUTO;
767                         return 0;
768                 }
769                 config_cover_letter = git_config_bool(var, value) ? COVER_ON : COVER_OFF;
770                 return 0;
771         }
772
773         return git_log_config(var, value, cb);
774 }
775
776 static FILE *realstdout = NULL;
777 static const char *output_directory = NULL;
778 static int outdir_offset;
779
780 static int reopen_stdout(struct commit *commit, const char *subject,
781                          struct rev_info *rev, int quiet)
782 {
783         struct strbuf filename = STRBUF_INIT;
784         int suffix_len = strlen(rev->patch_suffix) + 1;
785
786         if (output_directory) {
787                 strbuf_addstr(&filename, output_directory);
788                 if (filename.len >=
789                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
790                         return error(_("name of output directory is too long"));
791                 if (filename.buf[filename.len - 1] != '/')
792                         strbuf_addch(&filename, '/');
793         }
794
795         if (rev->numbered_files)
796                 strbuf_addf(&filename, "%d", rev->nr);
797         else if (commit)
798                 fmt_output_commit(&filename, commit, rev);
799         else
800                 fmt_output_subject(&filename, subject, rev);
801
802         if (!quiet)
803                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
804
805         if (freopen(filename.buf, "w", stdout) == NULL)
806                 return error(_("Cannot open patch file %s"), filename.buf);
807
808         strbuf_release(&filename);
809         return 0;
810 }
811
812 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids)
813 {
814         struct rev_info check_rev;
815         struct commit *commit, *c1, *c2;
816         struct object *o1, *o2;
817         unsigned flags1, flags2;
818
819         if (rev->pending.nr != 2)
820                 die(_("Need exactly one range."));
821
822         o1 = rev->pending.objects[0].item;
823         o2 = rev->pending.objects[1].item;
824         flags1 = o1->flags;
825         flags2 = o2->flags;
826         c1 = lookup_commit_reference(o1->sha1);
827         c2 = lookup_commit_reference(o2->sha1);
828
829         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
830                 die(_("Not a range."));
831
832         init_patch_ids(ids);
833
834         /* given a range a..b get all patch ids for b..a */
835         init_revisions(&check_rev, rev->prefix);
836         check_rev.max_parents = 1;
837         o1->flags ^= UNINTERESTING;
838         o2->flags ^= UNINTERESTING;
839         add_pending_object(&check_rev, o1, "o1");
840         add_pending_object(&check_rev, o2, "o2");
841         if (prepare_revision_walk(&check_rev))
842                 die(_("revision walk setup failed"));
843
844         while ((commit = get_revision(&check_rev)) != NULL) {
845                 add_commit_patch_id(commit, ids);
846         }
847
848         /* reset for next revision walk */
849         clear_commit_marks(c1, SEEN | UNINTERESTING | SHOWN | ADDED);
850         clear_commit_marks(c2, SEEN | UNINTERESTING | SHOWN | ADDED);
851         o1->flags = flags1;
852         o2->flags = flags2;
853 }
854
855 static void gen_message_id(struct rev_info *info, char *base)
856 {
857         struct strbuf buf = STRBUF_INIT;
858         strbuf_addf(&buf, "%s.%lu.git.%s", base,
859                     (unsigned long) time(NULL),
860                     git_committer_info(IDENT_NO_NAME|IDENT_NO_DATE|IDENT_STRICT));
861         info->message_id = strbuf_detach(&buf, NULL);
862 }
863
864 static void print_signature(void)
865 {
866         if (!signature || !*signature)
867                 return;
868
869         printf("-- \n%s", signature);
870         if (signature[strlen(signature)-1] != '\n')
871                 putchar('\n');
872         putchar('\n');
873 }
874
875 static void add_branch_description(struct strbuf *buf, const char *branch_name)
876 {
877         struct strbuf desc = STRBUF_INIT;
878         if (!branch_name || !*branch_name)
879                 return;
880         read_branch_desc(&desc, branch_name);
881         if (desc.len) {
882                 strbuf_addch(buf, '\n');
883                 strbuf_addbuf(buf, &desc);
884                 strbuf_addch(buf, '\n');
885         }
886         strbuf_release(&desc);
887 }
888
889 static char *find_branch_name(struct rev_info *rev)
890 {
891         int i, positive = -1;
892         unsigned char branch_sha1[20];
893         const unsigned char *tip_sha1;
894         const char *ref, *v;
895         char *full_ref, *branch = NULL;
896
897         for (i = 0; i < rev->cmdline.nr; i++) {
898                 if (rev->cmdline.rev[i].flags & UNINTERESTING)
899                         continue;
900                 if (positive < 0)
901                         positive = i;
902                 else
903                         return NULL;
904         }
905         if (positive < 0)
906                 return NULL;
907         ref = rev->cmdline.rev[positive].name;
908         tip_sha1 = rev->cmdline.rev[positive].item->sha1;
909         if (dwim_ref(ref, strlen(ref), branch_sha1, &full_ref) &&
910             skip_prefix(full_ref, "refs/heads/", &v) &&
911             !hashcmp(tip_sha1, branch_sha1))
912                 branch = xstrdup(v);
913         free(full_ref);
914         return branch;
915 }
916
917 static void make_cover_letter(struct rev_info *rev, int use_stdout,
918                               struct commit *origin,
919                               int nr, struct commit **list,
920                               const char *branch_name,
921                               int quiet)
922 {
923         const char *committer;
924         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
925         const char *msg;
926         struct shortlog log;
927         struct strbuf sb = STRBUF_INIT;
928         int i;
929         const char *encoding = "UTF-8";
930         struct diff_options opts;
931         int need_8bit_cte = 0;
932         struct pretty_print_context pp = {0};
933         struct commit *head = list[0];
934
935         if (rev->commit_format != CMIT_FMT_EMAIL)
936                 die(_("Cover letter needs email format"));
937
938         committer = git_committer_info(0);
939
940         if (!use_stdout &&
941             reopen_stdout(NULL, rev->numbered_files ? NULL : "cover-letter", rev, quiet))
942                 return;
943
944         log_write_email_headers(rev, head, &pp.subject, &pp.after_subject,
945                                 &need_8bit_cte);
946
947         for (i = 0; !need_8bit_cte && i < nr; i++) {
948                 const char *buf = get_commit_buffer(list[i], NULL);
949                 if (has_non_ascii(buf))
950                         need_8bit_cte = 1;
951                 unuse_commit_buffer(list[i], buf);
952         }
953
954         if (!branch_name)
955                 branch_name = find_branch_name(rev);
956
957         msg = body;
958         pp.fmt = CMIT_FMT_EMAIL;
959         pp.date_mode.type = DATE_RFC2822;
960         pp_user_info(&pp, NULL, &sb, committer, encoding);
961         pp_title_line(&pp, &msg, &sb, encoding, need_8bit_cte);
962         pp_remainder(&pp, &msg, &sb, 0);
963         add_branch_description(&sb, branch_name);
964         printf("%s\n", sb.buf);
965
966         strbuf_release(&sb);
967
968         shortlog_init(&log);
969         log.wrap_lines = 1;
970         log.wrap = 72;
971         log.in1 = 2;
972         log.in2 = 4;
973         for (i = 0; i < nr; i++)
974                 shortlog_add_commit(&log, list[i]);
975
976         shortlog_output(&log);
977
978         /*
979          * We can only do diffstat with a unique reference point
980          */
981         if (!origin)
982                 return;
983
984         memcpy(&opts, &rev->diffopt, sizeof(opts));
985         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
986
987         diff_setup_done(&opts);
988
989         diff_tree_sha1(origin->tree->object.sha1,
990                        head->tree->object.sha1,
991                        "", &opts);
992         diffcore_std(&opts);
993         diff_flush(&opts);
994
995         printf("\n");
996         print_signature();
997 }
998
999 static const char *clean_message_id(const char *msg_id)
1000 {
1001         char ch;
1002         const char *a, *z, *m;
1003
1004         m = msg_id;
1005         while ((ch = *m) && (isspace(ch) || (ch == '<')))
1006                 m++;
1007         a = m;
1008         z = NULL;
1009         while ((ch = *m)) {
1010                 if (!isspace(ch) && (ch != '>'))
1011                         z = m;
1012                 m++;
1013         }
1014         if (!z)
1015                 die(_("insane in-reply-to: %s"), msg_id);
1016         if (++z == m)
1017                 return a;
1018         return xmemdupz(a, z - a);
1019 }
1020
1021 static const char *set_outdir(const char *prefix, const char *output_directory)
1022 {
1023         if (output_directory && is_absolute_path(output_directory))
1024                 return output_directory;
1025
1026         if (!prefix || !*prefix) {
1027                 if (output_directory)
1028                         return output_directory;
1029                 /* The user did not explicitly ask for "./" */
1030                 outdir_offset = 2;
1031                 return "./";
1032         }
1033
1034         outdir_offset = strlen(prefix);
1035         if (!output_directory)
1036                 return prefix;
1037
1038         return xstrdup(prefix_filename(prefix, outdir_offset,
1039                                        output_directory));
1040 }
1041
1042 static const char * const builtin_format_patch_usage[] = {
1043         N_("git format-patch [<options>] [<since> | <revision-range>]"),
1044         NULL
1045 };
1046
1047 static int keep_subject = 0;
1048
1049 static int keep_callback(const struct option *opt, const char *arg, int unset)
1050 {
1051         ((struct rev_info *)opt->value)->total = -1;
1052         keep_subject = 1;
1053         return 0;
1054 }
1055
1056 static int subject_prefix = 0;
1057
1058 static int subject_prefix_callback(const struct option *opt, const char *arg,
1059                             int unset)
1060 {
1061         subject_prefix = 1;
1062         ((struct rev_info *)opt->value)->subject_prefix = arg;
1063         return 0;
1064 }
1065
1066 static int numbered_cmdline_opt = 0;
1067
1068 static int numbered_callback(const struct option *opt, const char *arg,
1069                              int unset)
1070 {
1071         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
1072         if (unset)
1073                 auto_number =  0;
1074         return 0;
1075 }
1076
1077 static int no_numbered_callback(const struct option *opt, const char *arg,
1078                                 int unset)
1079 {
1080         return numbered_callback(opt, arg, 1);
1081 }
1082
1083 static int output_directory_callback(const struct option *opt, const char *arg,
1084                               int unset)
1085 {
1086         const char **dir = (const char **)opt->value;
1087         if (*dir)
1088                 die(_("Two output directories?"));
1089         *dir = arg;
1090         return 0;
1091 }
1092
1093 static int thread_callback(const struct option *opt, const char *arg, int unset)
1094 {
1095         int *thread = (int *)opt->value;
1096         if (unset)
1097                 *thread = 0;
1098         else if (!arg || !strcmp(arg, "shallow"))
1099                 *thread = THREAD_SHALLOW;
1100         else if (!strcmp(arg, "deep"))
1101                 *thread = THREAD_DEEP;
1102         else
1103                 return 1;
1104         return 0;
1105 }
1106
1107 static int attach_callback(const struct option *opt, const char *arg, int unset)
1108 {
1109         struct rev_info *rev = (struct rev_info *)opt->value;
1110         if (unset)
1111                 rev->mime_boundary = NULL;
1112         else if (arg)
1113                 rev->mime_boundary = arg;
1114         else
1115                 rev->mime_boundary = git_version_string;
1116         rev->no_inline = unset ? 0 : 1;
1117         return 0;
1118 }
1119
1120 static int inline_callback(const struct option *opt, const char *arg, int unset)
1121 {
1122         struct rev_info *rev = (struct rev_info *)opt->value;
1123         if (unset)
1124                 rev->mime_boundary = NULL;
1125         else if (arg)
1126                 rev->mime_boundary = arg;
1127         else
1128                 rev->mime_boundary = git_version_string;
1129         rev->no_inline = 0;
1130         return 0;
1131 }
1132
1133 static int header_callback(const struct option *opt, const char *arg, int unset)
1134 {
1135         if (unset) {
1136                 string_list_clear(&extra_hdr, 0);
1137                 string_list_clear(&extra_to, 0);
1138                 string_list_clear(&extra_cc, 0);
1139         } else {
1140             add_header(arg);
1141         }
1142         return 0;
1143 }
1144
1145 static int to_callback(const struct option *opt, const char *arg, int unset)
1146 {
1147         if (unset)
1148                 string_list_clear(&extra_to, 0);
1149         else
1150                 string_list_append(&extra_to, arg);
1151         return 0;
1152 }
1153
1154 static int cc_callback(const struct option *opt, const char *arg, int unset)
1155 {
1156         if (unset)
1157                 string_list_clear(&extra_cc, 0);
1158         else
1159                 string_list_append(&extra_cc, arg);
1160         return 0;
1161 }
1162
1163 static int from_callback(const struct option *opt, const char *arg, int unset)
1164 {
1165         char **from = opt->value;
1166
1167         free(*from);
1168
1169         if (unset)
1170                 *from = NULL;
1171         else if (arg)
1172                 *from = xstrdup(arg);
1173         else
1174                 *from = xstrdup(git_committer_info(IDENT_NO_DATE));
1175         return 0;
1176 }
1177
1178 int cmd_format_patch(int argc, const char **argv, const char *prefix)
1179 {
1180         struct commit *commit;
1181         struct commit **list = NULL;
1182         struct rev_info rev;
1183         struct setup_revision_opt s_r_opt;
1184         int nr = 0, total, i;
1185         int use_stdout = 0;
1186         int start_number = -1;
1187         int just_numbers = 0;
1188         int ignore_if_in_upstream = 0;
1189         int cover_letter = -1;
1190         int boundary_count = 0;
1191         int no_binary_diff = 0;
1192         struct commit *origin = NULL;
1193         const char *in_reply_to = NULL;
1194         struct patch_ids ids;
1195         struct strbuf buf = STRBUF_INIT;
1196         int use_patch_format = 0;
1197         int quiet = 0;
1198         int reroll_count = -1;
1199         char *branch_name = NULL;
1200         char *from = NULL;
1201         const struct option builtin_format_patch_options[] = {
1202                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1203                             N_("use [PATCH n/m] even with a single patch"),
1204                             PARSE_OPT_NOARG, numbered_callback },
1205                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1206                             N_("use [PATCH] even with multiple patches"),
1207                             PARSE_OPT_NOARG, no_numbered_callback },
1208                 OPT_BOOL('s', "signoff", &do_signoff, N_("add Signed-off-by:")),
1209                 OPT_BOOL(0, "stdout", &use_stdout,
1210                             N_("print patches to standard out")),
1211                 OPT_BOOL(0, "cover-letter", &cover_letter,
1212                             N_("generate a cover letter")),
1213                 OPT_BOOL(0, "numbered-files", &just_numbers,
1214                             N_("use simple number sequence for output file names")),
1215                 OPT_STRING(0, "suffix", &fmt_patch_suffix, N_("sfx"),
1216                             N_("use <sfx> instead of '.patch'")),
1217                 OPT_INTEGER(0, "start-number", &start_number,
1218                             N_("start numbering patches at <n> instead of 1")),
1219                 OPT_INTEGER('v', "reroll-count", &reroll_count,
1220                             N_("mark the series as Nth re-roll")),
1221                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, N_("prefix"),
1222                             N_("Use [<prefix>] instead of [PATCH]"),
1223                             PARSE_OPT_NONEG, subject_prefix_callback },
1224                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1225                             N_("dir"), N_("store resulting files in <dir>"),
1226                             PARSE_OPT_NONEG, output_directory_callback },
1227                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1228                             N_("don't strip/add [PATCH]"),
1229                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1230                 OPT_BOOL(0, "no-binary", &no_binary_diff,
1231                          N_("don't output binary diffs")),
1232                 OPT_BOOL(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1233                          N_("don't include a patch matching a commit upstream")),
1234                 { OPTION_SET_INT, 'p', "no-stat", &use_patch_format, NULL,
1235                   N_("show patch format instead of default (patch + stat)"),
1236                   PARSE_OPT_NONEG | PARSE_OPT_NOARG, NULL, 1},
1237                 OPT_GROUP(N_("Messaging")),
1238                 { OPTION_CALLBACK, 0, "add-header", NULL, N_("header"),
1239                             N_("add email header"), 0, header_callback },
1240                 { OPTION_CALLBACK, 0, "to", NULL, N_("email"), N_("add To: header"),
1241                             0, to_callback },
1242                 { OPTION_CALLBACK, 0, "cc", NULL, N_("email"), N_("add Cc: header"),
1243                             0, cc_callback },
1244                 { OPTION_CALLBACK, 0, "from", &from, N_("ident"),
1245                             N_("set From address to <ident> (or committer ident if absent)"),
1246                             PARSE_OPT_OPTARG, from_callback },
1247                 OPT_STRING(0, "in-reply-to", &in_reply_to, N_("message-id"),
1248                             N_("make first mail a reply to <message-id>")),
1249                 { OPTION_CALLBACK, 0, "attach", &rev, N_("boundary"),
1250                             N_("attach the patch"), PARSE_OPT_OPTARG,
1251                             attach_callback },
1252                 { OPTION_CALLBACK, 0, "inline", &rev, N_("boundary"),
1253                             N_("inline the patch"),
1254                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1255                             inline_callback },
1256                 { OPTION_CALLBACK, 0, "thread", &thread, N_("style"),
1257                             N_("enable message threading, styles: shallow, deep"),
1258                             PARSE_OPT_OPTARG, thread_callback },
1259                 OPT_STRING(0, "signature", &signature, N_("signature"),
1260                             N_("add a signature")),
1261                 OPT_FILENAME(0, "signature-file", &signature_file,
1262                                 N_("add a signature from a file")),
1263                 OPT__QUIET(&quiet, N_("don't print the patch filenames")),
1264                 OPT_END()
1265         };
1266
1267         extra_hdr.strdup_strings = 1;
1268         extra_to.strdup_strings = 1;
1269         extra_cc.strdup_strings = 1;
1270         init_grep_defaults();
1271         git_config(git_format_config, NULL);
1272         init_revisions(&rev, prefix);
1273         rev.commit_format = CMIT_FMT_EMAIL;
1274         rev.verbose_header = 1;
1275         rev.diff = 1;
1276         rev.max_parents = 1;
1277         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1278         rev.subject_prefix = fmt_patch_subject_prefix;
1279         memset(&s_r_opt, 0, sizeof(s_r_opt));
1280         s_r_opt.def = "HEAD";
1281         s_r_opt.revarg_opt = REVARG_COMMITTISH;
1282
1283         if (default_attach) {
1284                 rev.mime_boundary = default_attach;
1285                 rev.no_inline = 1;
1286         }
1287
1288         /*
1289          * Parse the arguments before setup_revisions(), or something
1290          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1291          * possibly a valid SHA1.
1292          */
1293         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1294                              builtin_format_patch_usage,
1295                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1296                              PARSE_OPT_KEEP_DASHDASH);
1297
1298         if (0 < reroll_count) {
1299                 struct strbuf sprefix = STRBUF_INIT;
1300                 strbuf_addf(&sprefix, "%s v%d",
1301                             rev.subject_prefix, reroll_count);
1302                 rev.reroll_count = reroll_count;
1303                 rev.subject_prefix = strbuf_detach(&sprefix, NULL);
1304         }
1305
1306         for (i = 0; i < extra_hdr.nr; i++) {
1307                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1308                 strbuf_addch(&buf, '\n');
1309         }
1310
1311         if (extra_to.nr)
1312                 strbuf_addstr(&buf, "To: ");
1313         for (i = 0; i < extra_to.nr; i++) {
1314                 if (i)
1315                         strbuf_addstr(&buf, "    ");
1316                 strbuf_addstr(&buf, extra_to.items[i].string);
1317                 if (i + 1 < extra_to.nr)
1318                         strbuf_addch(&buf, ',');
1319                 strbuf_addch(&buf, '\n');
1320         }
1321
1322         if (extra_cc.nr)
1323                 strbuf_addstr(&buf, "Cc: ");
1324         for (i = 0; i < extra_cc.nr; i++) {
1325                 if (i)
1326                         strbuf_addstr(&buf, "    ");
1327                 strbuf_addstr(&buf, extra_cc.items[i].string);
1328                 if (i + 1 < extra_cc.nr)
1329                         strbuf_addch(&buf, ',');
1330                 strbuf_addch(&buf, '\n');
1331         }
1332
1333         rev.extra_headers = strbuf_detach(&buf, NULL);
1334
1335         if (from) {
1336                 if (split_ident_line(&rev.from_ident, from, strlen(from)))
1337                         die(_("invalid ident line: %s"), from);
1338         }
1339
1340         if (start_number < 0)
1341                 start_number = 1;
1342
1343         /*
1344          * If numbered is set solely due to format.numbered in config,
1345          * and it would conflict with --keep-subject (-k) from the
1346          * command line, reset "numbered".
1347          */
1348         if (numbered && keep_subject && !numbered_cmdline_opt)
1349                 numbered = 0;
1350
1351         if (numbered && keep_subject)
1352                 die (_("-n and -k are mutually exclusive."));
1353         if (keep_subject && subject_prefix)
1354                 die (_("--subject-prefix and -k are mutually exclusive."));
1355         rev.preserve_subject = keep_subject;
1356
1357         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1358         if (argc > 1)
1359                 die (_("unrecognized argument: %s"), argv[1]);
1360
1361         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1362                 die(_("--name-only does not make sense"));
1363         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1364                 die(_("--name-status does not make sense"));
1365         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1366                 die(_("--check does not make sense"));
1367
1368         if (!use_patch_format &&
1369                 (!rev.diffopt.output_format ||
1370                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1371                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1372
1373         /* Always generate a patch */
1374         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1375
1376         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1377                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1378
1379         if (rev.show_notes)
1380                 init_display_notes(&rev.notes_opt);
1381
1382         if (!use_stdout)
1383                 output_directory = set_outdir(prefix, output_directory);
1384         else
1385                 setup_pager();
1386
1387         if (output_directory) {
1388                 if (use_stdout)
1389                         die(_("standard output, or directory, which one?"));
1390                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1391                         die_errno(_("Could not create directory '%s'"),
1392                                   output_directory);
1393         }
1394
1395         if (rev.pending.nr == 1) {
1396                 int check_head = 0;
1397
1398                 if (rev.max_count < 0 && !rev.show_root_diff) {
1399                         /*
1400                          * This is traditional behaviour of "git format-patch
1401                          * origin" that prepares what the origin side still
1402                          * does not have.
1403                          */
1404                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1405                         add_head_to_pending(&rev);
1406                         check_head = 1;
1407                 }
1408                 /*
1409                  * Otherwise, it is "format-patch -22 HEAD", and/or
1410                  * "format-patch --root HEAD".  The user wants
1411                  * get_revision() to do the usual traversal.
1412                  */
1413
1414                 if (!strcmp(rev.pending.objects[0].name, "HEAD"))
1415                         check_head = 1;
1416
1417                 if (check_head) {
1418                         unsigned char sha1[20];
1419                         const char *ref, *v;
1420                         ref = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
1421                                                  sha1, NULL);
1422                         if (ref && skip_prefix(ref, "refs/heads/", &v))
1423                                 branch_name = xstrdup(v);
1424                         else
1425                                 branch_name = xstrdup(""); /* no branch */
1426                 }
1427         }
1428
1429         /*
1430          * We cannot move this anywhere earlier because we do want to
1431          * know if --root was given explicitly from the command line.
1432          */
1433         rev.show_root_diff = 1;
1434
1435         if (ignore_if_in_upstream) {
1436                 /* Don't say anything if head and upstream are the same. */
1437                 if (rev.pending.nr == 2) {
1438                         struct object_array_entry *o = rev.pending.objects;
1439                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1440                                 return 0;
1441                 }
1442                 get_patch_ids(&rev, &ids);
1443         }
1444
1445         if (!use_stdout)
1446                 realstdout = xfdopen(xdup(1), "w");
1447
1448         if (prepare_revision_walk(&rev))
1449                 die(_("revision walk setup failed"));
1450         rev.boundary = 1;
1451         while ((commit = get_revision(&rev)) != NULL) {
1452                 if (commit->object.flags & BOUNDARY) {
1453                         boundary_count++;
1454                         origin = (boundary_count == 1) ? commit : NULL;
1455                         continue;
1456                 }
1457
1458                 if (ignore_if_in_upstream &&
1459                                 has_commit_patch_id(commit, &ids))
1460                         continue;
1461
1462                 nr++;
1463                 REALLOC_ARRAY(list, nr);
1464                 list[nr - 1] = commit;
1465         }
1466         if (nr == 0)
1467                 /* nothing to do */
1468                 return 0;
1469         total = nr;
1470         if (!keep_subject && auto_number && total > 1)
1471                 numbered = 1;
1472         if (numbered)
1473                 rev.total = total + start_number - 1;
1474         if (cover_letter == -1) {
1475                 if (config_cover_letter == COVER_AUTO)
1476                         cover_letter = (total > 1);
1477                 else
1478                         cover_letter = (config_cover_letter == COVER_ON);
1479         }
1480
1481         if (!signature) {
1482                 ; /* --no-signature inhibits all signatures */
1483         } else if (signature && signature != git_version_string) {
1484                 ; /* non-default signature already set */
1485         } else if (signature_file) {
1486                 struct strbuf buf = STRBUF_INIT;
1487
1488                 if (strbuf_read_file(&buf, signature_file, 128) < 0)
1489                         die_errno(_("unable to read signature file '%s'"), signature_file);
1490                 signature = strbuf_detach(&buf, NULL);
1491         }
1492
1493         if (in_reply_to || thread || cover_letter)
1494                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1495         if (in_reply_to) {
1496                 const char *msgid = clean_message_id(in_reply_to);
1497                 string_list_append(rev.ref_message_ids, msgid);
1498         }
1499         rev.numbered_files = just_numbers;
1500         rev.patch_suffix = fmt_patch_suffix;
1501         if (cover_letter) {
1502                 if (thread)
1503                         gen_message_id(&rev, "cover");
1504                 make_cover_letter(&rev, use_stdout,
1505                                   origin, nr, list, branch_name, quiet);
1506                 total++;
1507                 start_number--;
1508         }
1509         rev.add_signoff = do_signoff;
1510         while (0 <= --nr) {
1511                 int shown;
1512                 commit = list[nr];
1513                 rev.nr = total - nr + (start_number - 1);
1514                 /* Make the second and subsequent mails replies to the first */
1515                 if (thread) {
1516                         /* Have we already had a message ID? */
1517                         if (rev.message_id) {
1518                                 /*
1519                                  * For deep threading: make every mail
1520                                  * a reply to the previous one, no
1521                                  * matter what other options are set.
1522                                  *
1523                                  * For shallow threading:
1524                                  *
1525                                  * Without --cover-letter and
1526                                  * --in-reply-to, make every mail a
1527                                  * reply to the one before.
1528                                  *
1529                                  * With --in-reply-to but no
1530                                  * --cover-letter, make every mail a
1531                                  * reply to the <reply-to>.
1532                                  *
1533                                  * With --cover-letter, make every
1534                                  * mail but the cover letter a reply
1535                                  * to the cover letter.  The cover
1536                                  * letter is a reply to the
1537                                  * --in-reply-to, if specified.
1538                                  */
1539                                 if (thread == THREAD_SHALLOW
1540                                     && rev.ref_message_ids->nr > 0
1541                                     && (!cover_letter || rev.nr > 1))
1542                                         free(rev.message_id);
1543                                 else
1544                                         string_list_append(rev.ref_message_ids,
1545                                                            rev.message_id);
1546                         }
1547                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1548                 }
1549
1550                 if (!use_stdout &&
1551                     reopen_stdout(rev.numbered_files ? NULL : commit, NULL, &rev, quiet))
1552                         die(_("Failed to create output files"));
1553                 shown = log_tree_commit(&rev, commit);
1554                 free_commit_buffer(commit);
1555
1556                 /* We put one extra blank line between formatted
1557                  * patches and this flag is used by log-tree code
1558                  * to see if it needs to emit a LF before showing
1559                  * the log; when using one file per patch, we do
1560                  * not want the extra blank line.
1561                  */
1562                 if (!use_stdout)
1563                         rev.shown_one = 0;
1564                 if (shown) {
1565                         if (rev.mime_boundary)
1566                                 printf("\n--%s%s--\n\n\n",
1567                                        mime_boundary_leader,
1568                                        rev.mime_boundary);
1569                         else
1570                                 print_signature();
1571                 }
1572                 if (!use_stdout)
1573                         fclose(stdout);
1574         }
1575         free(list);
1576         free(branch_name);
1577         string_list_clear(&extra_to, 0);
1578         string_list_clear(&extra_cc, 0);
1579         string_list_clear(&extra_hdr, 0);
1580         if (ignore_if_in_upstream)
1581                 free_patch_ids(&ids);
1582         return 0;
1583 }
1584
1585 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1586 {
1587         unsigned char sha1[20];
1588         if (get_sha1(arg, sha1) == 0) {
1589                 struct commit *commit = lookup_commit_reference(sha1);
1590                 if (commit) {
1591                         commit->object.flags |= flags;
1592                         add_pending_object(revs, &commit->object, arg);
1593                         return 0;
1594                 }
1595         }
1596         return -1;
1597 }
1598
1599 static const char * const cherry_usage[] = {
1600         N_("git cherry [-v] [<upstream> [<head> [<limit>]]]"),
1601         NULL
1602 };
1603
1604 static void print_commit(char sign, struct commit *commit, int verbose,
1605                          int abbrev)
1606 {
1607         if (!verbose) {
1608                 printf("%c %s\n", sign,
1609                        find_unique_abbrev(commit->object.sha1, abbrev));
1610         } else {
1611                 struct strbuf buf = STRBUF_INIT;
1612                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
1613                 printf("%c %s %s\n", sign,
1614                        find_unique_abbrev(commit->object.sha1, abbrev),
1615                        buf.buf);
1616                 strbuf_release(&buf);
1617         }
1618 }
1619
1620 int cmd_cherry(int argc, const char **argv, const char *prefix)
1621 {
1622         struct rev_info revs;
1623         struct patch_ids ids;
1624         struct commit *commit;
1625         struct commit_list *list = NULL;
1626         struct branch *current_branch;
1627         const char *upstream;
1628         const char *head = "HEAD";
1629         const char *limit = NULL;
1630         int verbose = 0, abbrev = 0;
1631
1632         struct option options[] = {
1633                 OPT__ABBREV(&abbrev),
1634                 OPT__VERBOSE(&verbose, N_("be verbose")),
1635                 OPT_END()
1636         };
1637
1638         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1639
1640         switch (argc) {
1641         case 3:
1642                 limit = argv[2];
1643                 /* FALLTHROUGH */
1644         case 2:
1645                 head = argv[1];
1646                 /* FALLTHROUGH */
1647         case 1:
1648                 upstream = argv[0];
1649                 break;
1650         default:
1651                 current_branch = branch_get(NULL);
1652                 upstream = branch_get_upstream(current_branch, NULL);
1653                 if (!upstream) {
1654                         fprintf(stderr, _("Could not find a tracked"
1655                                         " remote branch, please"
1656                                         " specify <upstream> manually.\n"));
1657                         usage_with_options(cherry_usage, options);
1658                 }
1659         }
1660
1661         init_revisions(&revs, prefix);
1662         revs.max_parents = 1;
1663
1664         if (add_pending_commit(head, &revs, 0))
1665                 die(_("Unknown commit %s"), head);
1666         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1667                 die(_("Unknown commit %s"), upstream);
1668
1669         /* Don't say anything if head and upstream are the same. */
1670         if (revs.pending.nr == 2) {
1671                 struct object_array_entry *o = revs.pending.objects;
1672                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1673                         return 0;
1674         }
1675
1676         get_patch_ids(&revs, &ids);
1677
1678         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1679                 die(_("Unknown commit %s"), limit);
1680
1681         /* reverse the list of commits */
1682         if (prepare_revision_walk(&revs))
1683                 die(_("revision walk setup failed"));
1684         while ((commit = get_revision(&revs)) != NULL) {
1685                 commit_list_insert(commit, &list);
1686         }
1687
1688         while (list) {
1689                 char sign = '+';
1690
1691                 commit = list->item;
1692                 if (has_commit_patch_id(commit, &ids))
1693                         sign = '-';
1694                 print_commit(sign, commit, verbose, abbrev);
1695                 list = list->next;
1696         }
1697
1698         free_patch_ids(&ids);
1699         return 0;
1700 }