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