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