git-remote-mediawiki: get rid of O(N^2) loop
[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         "git log [<options>] [<since>..<until>] [[--] <path>...]\n"
38         "   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, "suppress diff output"),
101                 OPT_BOOLEAN(0, "source", &source, "show source"),
102                 { OPTION_CALLBACK, 0, "decorate", NULL, NULL, "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         argc = setup_revisions(argc, argv, rev, opt);
113         if (quiet)
114                 rev->diffopt.output_format |= DIFF_FORMAT_NO_OUTPUT;
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
355         return git_diff_ui_config(var, value, cb);
356 }
357
358 int cmd_whatchanged(int argc, const char **argv, const char *prefix)
359 {
360         struct rev_info rev;
361         struct setup_revision_opt opt;
362
363         git_config(git_log_config, NULL);
364
365         init_revisions(&rev, prefix);
366         rev.diff = 1;
367         rev.simplify_history = 0;
368         memset(&opt, 0, sizeof(opt));
369         opt.def = "HEAD";
370         cmd_log_init(argc, argv, prefix, &rev, &opt);
371         if (!rev.diffopt.output_format)
372                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
373         return cmd_log_walk(&rev);
374 }
375
376 static void show_tagger(char *buf, int len, struct rev_info *rev)
377 {
378         struct strbuf out = STRBUF_INIT;
379         struct pretty_print_context pp = {0};
380
381         pp.fmt = rev->commit_format;
382         pp.date_mode = rev->date_mode;
383         pp_user_info(&pp, "Tagger", &out, buf, get_log_output_encoding());
384         printf("%s", out.buf);
385         strbuf_release(&out);
386 }
387
388 static int show_blob_object(const unsigned char *sha1, struct rev_info *rev)
389 {
390         fflush(stdout);
391         return stream_blob_to_fd(1, sha1, NULL, 0);
392 }
393
394 static int show_tag_object(const unsigned char *sha1, struct rev_info *rev)
395 {
396         unsigned long size;
397         enum object_type type;
398         char *buf = read_sha1_file(sha1, &type, &size);
399         int offset = 0;
400
401         if (!buf)
402                 return error(_("Could not read object %s"), sha1_to_hex(sha1));
403
404         assert(type == OBJ_TAG);
405         while (offset < size && buf[offset] != '\n') {
406                 int new_offset = offset + 1;
407                 while (new_offset < size && buf[new_offset++] != '\n')
408                         ; /* do nothing */
409                 if (!prefixcmp(buf + offset, "tagger "))
410                         show_tagger(buf + offset + 7,
411                                     new_offset - offset - 7, rev);
412                 offset = new_offset;
413         }
414
415         if (offset < size)
416                 fwrite(buf + offset, size - offset, 1, stdout);
417         free(buf);
418         return 0;
419 }
420
421 static int show_tree_object(const unsigned char *sha1,
422                 const char *base, int baselen,
423                 const char *pathname, unsigned mode, int stage, void *context)
424 {
425         printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
426         return 0;
427 }
428
429 static void show_rev_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
430 {
431         if (rev->ignore_merges) {
432                 /* There was no "-m" on the command line */
433                 rev->ignore_merges = 0;
434                 if (!rev->first_parent_only && !rev->combine_merges) {
435                         /* No "--first-parent", "-c", nor "--cc" */
436                         rev->combine_merges = 1;
437                         rev->dense_combined_merges = 1;
438                 }
439         }
440         if (!rev->diffopt.output_format)
441                 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
442 }
443
444 int cmd_show(int argc, const char **argv, const char *prefix)
445 {
446         struct rev_info rev;
447         struct object_array_entry *objects;
448         struct setup_revision_opt opt;
449         struct pathspec match_all;
450         int i, count, ret = 0;
451
452         git_config(git_log_config, NULL);
453
454         init_pathspec(&match_all, NULL);
455         init_revisions(&rev, prefix);
456         rev.diff = 1;
457         rev.always_show_header = 1;
458         rev.no_walk = 1;
459         rev.diffopt.stat_width = -1;    /* Scale to real terminal size */
460
461         memset(&opt, 0, sizeof(opt));
462         opt.def = "HEAD";
463         opt.tweak = show_rev_tweak_rev;
464         cmd_log_init(argc, argv, prefix, &rev, &opt);
465
466         if (!rev.no_walk)
467                 return cmd_log_walk(&rev);
468
469         count = rev.pending.nr;
470         objects = rev.pending.objects;
471         for (i = 0; i < count && !ret; i++) {
472                 struct object *o = objects[i].item;
473                 const char *name = objects[i].name;
474                 switch (o->type) {
475                 case OBJ_BLOB:
476                         ret = show_blob_object(o->sha1, NULL);
477                         break;
478                 case OBJ_TAG: {
479                         struct tag *t = (struct tag *)o;
480
481                         if (rev.shown_one)
482                                 putchar('\n');
483                         printf("%stag %s%s\n",
484                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
485                                         t->tag,
486                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
487                         ret = show_tag_object(o->sha1, &rev);
488                         rev.shown_one = 1;
489                         if (ret)
490                                 break;
491                         o = parse_object(t->tagged->sha1);
492                         if (!o)
493                                 ret = error(_("Could not read object %s"),
494                                             sha1_to_hex(t->tagged->sha1));
495                         objects[i].item = o;
496                         i--;
497                         break;
498                 }
499                 case OBJ_TREE:
500                         if (rev.shown_one)
501                                 putchar('\n');
502                         printf("%stree %s%s\n\n",
503                                         diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
504                                         name,
505                                         diff_get_color_opt(&rev.diffopt, DIFF_RESET));
506                         read_tree_recursive((struct tree *)o, "", 0, 0, &match_all,
507                                         show_tree_object, NULL);
508                         rev.shown_one = 1;
509                         break;
510                 case OBJ_COMMIT:
511                         rev.pending.nr = rev.pending.alloc = 0;
512                         rev.pending.objects = NULL;
513                         add_object_array(o, name, &rev.pending);
514                         ret = cmd_log_walk(&rev);
515                         break;
516                 default:
517                         ret = error(_("Unknown type: %d"), o->type);
518                 }
519         }
520         free(objects);
521         return ret;
522 }
523
524 /*
525  * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
526  */
527 int cmd_log_reflog(int argc, const char **argv, const char *prefix)
528 {
529         struct rev_info rev;
530         struct setup_revision_opt opt;
531
532         git_config(git_log_config, NULL);
533
534         init_revisions(&rev, prefix);
535         init_reflog_walk(&rev.reflog_info);
536         rev.verbose_header = 1;
537         memset(&opt, 0, sizeof(opt));
538         opt.def = "HEAD";
539         cmd_log_init_defaults(&rev);
540         rev.abbrev_commit = 1;
541         rev.commit_format = CMIT_FMT_ONELINE;
542         rev.use_terminator = 1;
543         rev.always_show_header = 1;
544         cmd_log_init_finish(argc, argv, prefix, &rev, &opt);
545
546         return cmd_log_walk(&rev);
547 }
548
549 int cmd_log(int argc, const char **argv, const char *prefix)
550 {
551         struct rev_info rev;
552         struct setup_revision_opt opt;
553
554         git_config(git_log_config, NULL);
555
556         init_revisions(&rev, prefix);
557         rev.always_show_header = 1;
558         memset(&opt, 0, sizeof(opt));
559         opt.def = "HEAD";
560         cmd_log_init(argc, argv, prefix, &rev, &opt);
561         return cmd_log_walk(&rev);
562 }
563
564 /* format-patch */
565
566 static const char *fmt_patch_suffix = ".patch";
567 static int numbered = 0;
568 static int auto_number = 1;
569
570 static char *default_attach = NULL;
571
572 static struct string_list extra_hdr;
573 static struct string_list extra_to;
574 static struct string_list extra_cc;
575
576 static void add_header(const char *value)
577 {
578         struct string_list_item *item;
579         int len = strlen(value);
580         while (len && value[len - 1] == '\n')
581                 len--;
582
583         if (!strncasecmp(value, "to: ", 4)) {
584                 item = string_list_append(&extra_to, value + 4);
585                 len -= 4;
586         } else if (!strncasecmp(value, "cc: ", 4)) {
587                 item = string_list_append(&extra_cc, value + 4);
588                 len -= 4;
589         } else {
590                 item = string_list_append(&extra_hdr, value);
591         }
592
593         item->string[len] = '\0';
594 }
595
596 #define THREAD_SHALLOW 1
597 #define THREAD_DEEP 2
598 static int thread;
599 static int do_signoff;
600 static const char *signature = git_version_string;
601
602 static int git_format_config(const char *var, const char *value, void *cb)
603 {
604         if (!strcmp(var, "format.headers")) {
605                 if (!value)
606                         die(_("format.headers without value"));
607                 add_header(value);
608                 return 0;
609         }
610         if (!strcmp(var, "format.suffix"))
611                 return git_config_string(&fmt_patch_suffix, var, value);
612         if (!strcmp(var, "format.to")) {
613                 if (!value)
614                         return config_error_nonbool(var);
615                 string_list_append(&extra_to, value);
616                 return 0;
617         }
618         if (!strcmp(var, "format.cc")) {
619                 if (!value)
620                         return config_error_nonbool(var);
621                 string_list_append(&extra_cc, value);
622                 return 0;
623         }
624         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff") ||
625             !strcmp(var, "color.ui")) {
626                 return 0;
627         }
628         if (!strcmp(var, "format.numbered")) {
629                 if (value && !strcasecmp(value, "auto")) {
630                         auto_number = 1;
631                         return 0;
632                 }
633                 numbered = git_config_bool(var, value);
634                 auto_number = auto_number && numbered;
635                 return 0;
636         }
637         if (!strcmp(var, "format.attach")) {
638                 if (value && *value)
639                         default_attach = xstrdup(value);
640                 else
641                         default_attach = xstrdup(git_version_string);
642                 return 0;
643         }
644         if (!strcmp(var, "format.thread")) {
645                 if (value && !strcasecmp(value, "deep")) {
646                         thread = THREAD_DEEP;
647                         return 0;
648                 }
649                 if (value && !strcasecmp(value, "shallow")) {
650                         thread = THREAD_SHALLOW;
651                         return 0;
652                 }
653                 thread = git_config_bool(var, value) && THREAD_SHALLOW;
654                 return 0;
655         }
656         if (!strcmp(var, "format.signoff")) {
657                 do_signoff = git_config_bool(var, value);
658                 return 0;
659         }
660         if (!strcmp(var, "format.signature"))
661                 return git_config_string(&signature, var, value);
662
663         return git_log_config(var, value, cb);
664 }
665
666 static FILE *realstdout = NULL;
667 static const char *output_directory = NULL;
668 static int outdir_offset;
669
670 static int reopen_stdout(struct commit *commit, const char *subject,
671                          struct rev_info *rev, int quiet)
672 {
673         struct strbuf filename = STRBUF_INIT;
674         int suffix_len = strlen(fmt_patch_suffix) + 1;
675
676         if (output_directory) {
677                 strbuf_addstr(&filename, output_directory);
678                 if (filename.len >=
679                     PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
680                         return error(_("name of output directory is too long"));
681                 if (filename.buf[filename.len - 1] != '/')
682                         strbuf_addch(&filename, '/');
683         }
684
685         get_patch_filename(commit, subject, rev->nr, fmt_patch_suffix, &filename);
686
687         if (!quiet)
688                 fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
689
690         if (freopen(filename.buf, "w", stdout) == NULL)
691                 return error(_("Cannot open patch file %s"), filename.buf);
692
693         strbuf_release(&filename);
694         return 0;
695 }
696
697 static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix)
698 {
699         struct rev_info check_rev;
700         struct commit *commit;
701         struct object *o1, *o2;
702         unsigned flags1, flags2;
703
704         if (rev->pending.nr != 2)
705                 die(_("Need exactly one range."));
706
707         o1 = rev->pending.objects[0].item;
708         flags1 = o1->flags;
709         o2 = rev->pending.objects[1].item;
710         flags2 = o2->flags;
711
712         if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
713                 die(_("Not a range."));
714
715         init_patch_ids(ids);
716
717         /* given a range a..b get all patch ids for b..a */
718         init_revisions(&check_rev, prefix);
719         o1->flags ^= UNINTERESTING;
720         o2->flags ^= UNINTERESTING;
721         add_pending_object(&check_rev, o1, "o1");
722         add_pending_object(&check_rev, o2, "o2");
723         if (prepare_revision_walk(&check_rev))
724                 die(_("revision walk setup failed"));
725
726         while ((commit = get_revision(&check_rev)) != NULL) {
727                 /* ignore merges */
728                 if (commit->parents && commit->parents->next)
729                         continue;
730
731                 add_commit_patch_id(commit, ids);
732         }
733
734         /* reset for next revision walk */
735         clear_commit_marks((struct commit *)o1,
736                         SEEN | UNINTERESTING | SHOWN | ADDED);
737         clear_commit_marks((struct commit *)o2,
738                         SEEN | UNINTERESTING | SHOWN | ADDED);
739         o1->flags = flags1;
740         o2->flags = flags2;
741 }
742
743 static void gen_message_id(struct rev_info *info, char *base)
744 {
745         struct strbuf buf = STRBUF_INIT;
746         strbuf_addf(&buf, "%s.%lu.git.%s", base,
747                     (unsigned long) time(NULL),
748                     git_committer_info(IDENT_NO_NAME|IDENT_NO_DATE|IDENT_STRICT));
749         info->message_id = strbuf_detach(&buf, NULL);
750 }
751
752 static void print_signature(void)
753 {
754         if (signature && *signature)
755                 printf("-- \n%s\n\n", signature);
756 }
757
758 static void add_branch_description(struct strbuf *buf, const char *branch_name)
759 {
760         struct strbuf desc = STRBUF_INIT;
761         if (!branch_name || !*branch_name)
762                 return;
763         read_branch_desc(&desc, branch_name);
764         if (desc.len) {
765                 strbuf_addch(buf, '\n');
766                 strbuf_add(buf, desc.buf, desc.len);
767                 strbuf_addch(buf, '\n');
768         }
769 }
770
771 static void make_cover_letter(struct rev_info *rev, int use_stdout,
772                               int numbered, int numbered_files,
773                               struct commit *origin,
774                               int nr, struct commit **list, struct commit *head,
775                               const char *branch_name,
776                               int quiet)
777 {
778         const char *committer;
779         const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
780         const char *msg;
781         struct shortlog log;
782         struct strbuf sb = STRBUF_INIT;
783         int i;
784         const char *encoding = "UTF-8";
785         struct diff_options opts;
786         int need_8bit_cte = 0;
787         struct pretty_print_context pp = {0};
788
789         if (rev->commit_format != CMIT_FMT_EMAIL)
790                 die(_("Cover letter needs email format"));
791
792         committer = git_committer_info(0);
793
794         if (!use_stdout &&
795             reopen_stdout(NULL, numbered_files ? NULL : "cover-letter", rev, quiet))
796                 return;
797
798         log_write_email_headers(rev, head, &pp.subject, &pp.after_subject,
799                                 &need_8bit_cte);
800
801         for (i = 0; !need_8bit_cte && i < nr; i++)
802                 if (has_non_ascii(list[i]->buffer))
803                         need_8bit_cte = 1;
804
805         msg = body;
806         pp.fmt = CMIT_FMT_EMAIL;
807         pp.date_mode = DATE_RFC2822;
808         pp_user_info(&pp, NULL, &sb, committer, encoding);
809         pp_title_line(&pp, &msg, &sb, encoding, need_8bit_cte);
810         pp_remainder(&pp, &msg, &sb, 0);
811         add_branch_description(&sb, branch_name);
812         printf("%s\n", sb.buf);
813
814         strbuf_release(&sb);
815
816         shortlog_init(&log);
817         log.wrap_lines = 1;
818         log.wrap = 72;
819         log.in1 = 2;
820         log.in2 = 4;
821         for (i = 0; i < nr; i++)
822                 shortlog_add_commit(&log, list[i]);
823
824         shortlog_output(&log);
825
826         /*
827          * We can only do diffstat with a unique reference point
828          */
829         if (!origin)
830                 return;
831
832         memcpy(&opts, &rev->diffopt, sizeof(opts));
833         opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
834
835         diff_setup_done(&opts);
836
837         diff_tree_sha1(origin->tree->object.sha1,
838                        head->tree->object.sha1,
839                        "", &opts);
840         diffcore_std(&opts);
841         diff_flush(&opts);
842
843         printf("\n");
844         print_signature();
845 }
846
847 static const char *clean_message_id(const char *msg_id)
848 {
849         char ch;
850         const char *a, *z, *m;
851
852         m = msg_id;
853         while ((ch = *m) && (isspace(ch) || (ch == '<')))
854                 m++;
855         a = m;
856         z = NULL;
857         while ((ch = *m)) {
858                 if (!isspace(ch) && (ch != '>'))
859                         z = m;
860                 m++;
861         }
862         if (!z)
863                 die(_("insane in-reply-to: %s"), msg_id);
864         if (++z == m)
865                 return a;
866         return xmemdupz(a, z - a);
867 }
868
869 static const char *set_outdir(const char *prefix, const char *output_directory)
870 {
871         if (output_directory && is_absolute_path(output_directory))
872                 return output_directory;
873
874         if (!prefix || !*prefix) {
875                 if (output_directory)
876                         return output_directory;
877                 /* The user did not explicitly ask for "./" */
878                 outdir_offset = 2;
879                 return "./";
880         }
881
882         outdir_offset = strlen(prefix);
883         if (!output_directory)
884                 return prefix;
885
886         return xstrdup(prefix_filename(prefix, outdir_offset,
887                                        output_directory));
888 }
889
890 static const char * const builtin_format_patch_usage[] = {
891         "git format-patch [options] [<since> | <revision range>]",
892         NULL
893 };
894
895 static int keep_subject = 0;
896
897 static int keep_callback(const struct option *opt, const char *arg, int unset)
898 {
899         ((struct rev_info *)opt->value)->total = -1;
900         keep_subject = 1;
901         return 0;
902 }
903
904 static int subject_prefix = 0;
905
906 static int subject_prefix_callback(const struct option *opt, const char *arg,
907                             int unset)
908 {
909         subject_prefix = 1;
910         ((struct rev_info *)opt->value)->subject_prefix = arg;
911         return 0;
912 }
913
914 static int numbered_cmdline_opt = 0;
915
916 static int numbered_callback(const struct option *opt, const char *arg,
917                              int unset)
918 {
919         *(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
920         if (unset)
921                 auto_number =  0;
922         return 0;
923 }
924
925 static int no_numbered_callback(const struct option *opt, const char *arg,
926                                 int unset)
927 {
928         return numbered_callback(opt, arg, 1);
929 }
930
931 static int output_directory_callback(const struct option *opt, const char *arg,
932                               int unset)
933 {
934         const char **dir = (const char **)opt->value;
935         if (*dir)
936                 die(_("Two output directories?"));
937         *dir = arg;
938         return 0;
939 }
940
941 static int thread_callback(const struct option *opt, const char *arg, int unset)
942 {
943         int *thread = (int *)opt->value;
944         if (unset)
945                 *thread = 0;
946         else if (!arg || !strcmp(arg, "shallow"))
947                 *thread = THREAD_SHALLOW;
948         else if (!strcmp(arg, "deep"))
949                 *thread = THREAD_DEEP;
950         else
951                 return 1;
952         return 0;
953 }
954
955 static int attach_callback(const struct option *opt, const char *arg, int unset)
956 {
957         struct rev_info *rev = (struct rev_info *)opt->value;
958         if (unset)
959                 rev->mime_boundary = NULL;
960         else if (arg)
961                 rev->mime_boundary = arg;
962         else
963                 rev->mime_boundary = git_version_string;
964         rev->no_inline = unset ? 0 : 1;
965         return 0;
966 }
967
968 static int inline_callback(const struct option *opt, const char *arg, int unset)
969 {
970         struct rev_info *rev = (struct rev_info *)opt->value;
971         if (unset)
972                 rev->mime_boundary = NULL;
973         else if (arg)
974                 rev->mime_boundary = arg;
975         else
976                 rev->mime_boundary = git_version_string;
977         rev->no_inline = 0;
978         return 0;
979 }
980
981 static int header_callback(const struct option *opt, const char *arg, int unset)
982 {
983         if (unset) {
984                 string_list_clear(&extra_hdr, 0);
985                 string_list_clear(&extra_to, 0);
986                 string_list_clear(&extra_cc, 0);
987         } else {
988             add_header(arg);
989         }
990         return 0;
991 }
992
993 static int to_callback(const struct option *opt, const char *arg, int unset)
994 {
995         if (unset)
996                 string_list_clear(&extra_to, 0);
997         else
998                 string_list_append(&extra_to, arg);
999         return 0;
1000 }
1001
1002 static int cc_callback(const struct option *opt, const char *arg, int unset)
1003 {
1004         if (unset)
1005                 string_list_clear(&extra_cc, 0);
1006         else
1007                 string_list_append(&extra_cc, arg);
1008         return 0;
1009 }
1010
1011 static char *find_branch_name(struct rev_info *rev)
1012 {
1013         int i, positive = -1;
1014         unsigned char branch_sha1[20];
1015         struct strbuf buf = STRBUF_INIT;
1016         const char *branch;
1017
1018         for (i = 0; i < rev->cmdline.nr; i++) {
1019                 if (rev->cmdline.rev[i].flags & UNINTERESTING)
1020                         continue;
1021                 if (positive < 0)
1022                         positive = i;
1023                 else
1024                         return NULL;
1025         }
1026         if (positive < 0)
1027                 return NULL;
1028         strbuf_addf(&buf, "refs/heads/%s", rev->cmdline.rev[positive].name);
1029         branch = resolve_ref_unsafe(buf.buf, branch_sha1, 1, NULL);
1030         if (!branch ||
1031             prefixcmp(branch, "refs/heads/") ||
1032             hashcmp(rev->cmdline.rev[positive].item->sha1, branch_sha1))
1033                 branch = NULL;
1034         strbuf_release(&buf);
1035         if (branch)
1036                 return xstrdup(rev->cmdline.rev[positive].name);
1037         return NULL;
1038 }
1039
1040 int cmd_format_patch(int argc, const char **argv, const char *prefix)
1041 {
1042         struct commit *commit;
1043         struct commit **list = NULL;
1044         struct rev_info rev;
1045         struct setup_revision_opt s_r_opt;
1046         int nr = 0, total, i;
1047         int use_stdout = 0;
1048         int start_number = -1;
1049         int numbered_files = 0;         /* _just_ numbers */
1050         int ignore_if_in_upstream = 0;
1051         int cover_letter = 0;
1052         int boundary_count = 0;
1053         int no_binary_diff = 0;
1054         struct commit *origin = NULL, *head = NULL;
1055         const char *in_reply_to = NULL;
1056         struct patch_ids ids;
1057         char *add_signoff = NULL;
1058         struct strbuf buf = STRBUF_INIT;
1059         int use_patch_format = 0;
1060         int quiet = 0;
1061         char *branch_name = NULL;
1062         const struct option builtin_format_patch_options[] = {
1063                 { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
1064                             "use [PATCH n/m] even with a single patch",
1065                             PARSE_OPT_NOARG, numbered_callback },
1066                 { OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
1067                             "use [PATCH] even with multiple patches",
1068                             PARSE_OPT_NOARG, no_numbered_callback },
1069                 OPT_BOOLEAN('s', "signoff", &do_signoff, "add Signed-off-by:"),
1070                 OPT_BOOLEAN(0, "stdout", &use_stdout,
1071                             "print patches to standard out"),
1072                 OPT_BOOLEAN(0, "cover-letter", &cover_letter,
1073                             "generate a cover letter"),
1074                 OPT_BOOLEAN(0, "numbered-files", &numbered_files,
1075                             "use simple number sequence for output file names"),
1076                 OPT_STRING(0, "suffix", &fmt_patch_suffix, "sfx",
1077                             "use <sfx> instead of '.patch'"),
1078                 OPT_INTEGER(0, "start-number", &start_number,
1079                             "start numbering patches at <n> instead of 1"),
1080                 { OPTION_CALLBACK, 0, "subject-prefix", &rev, "prefix",
1081                             "Use [<prefix>] instead of [PATCH]",
1082                             PARSE_OPT_NONEG, subject_prefix_callback },
1083                 { OPTION_CALLBACK, 'o', "output-directory", &output_directory,
1084                             "dir", "store resulting files in <dir>",
1085                             PARSE_OPT_NONEG, output_directory_callback },
1086                 { OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
1087                             "don't strip/add [PATCH]",
1088                             PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
1089                 OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
1090                             "don't output binary diffs"),
1091                 OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
1092                             "don't include a patch matching a commit upstream"),
1093                 { OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
1094                   "show patch format instead of default (patch + stat)",
1095                   PARSE_OPT_NONEG | PARSE_OPT_NOARG },
1096                 OPT_GROUP("Messaging"),
1097                 { OPTION_CALLBACK, 0, "add-header", NULL, "header",
1098                             "add email header", 0, header_callback },
1099                 { OPTION_CALLBACK, 0, "to", NULL, "email", "add To: header",
1100                             0, to_callback },
1101                 { OPTION_CALLBACK, 0, "cc", NULL, "email", "add Cc: header",
1102                             0, cc_callback },
1103                 OPT_STRING(0, "in-reply-to", &in_reply_to, "message-id",
1104                             "make first mail a reply to <message-id>"),
1105                 { OPTION_CALLBACK, 0, "attach", &rev, "boundary",
1106                             "attach the patch", PARSE_OPT_OPTARG,
1107                             attach_callback },
1108                 { OPTION_CALLBACK, 0, "inline", &rev, "boundary",
1109                             "inline the patch",
1110                             PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
1111                             inline_callback },
1112                 { OPTION_CALLBACK, 0, "thread", &thread, "style",
1113                             "enable message threading, styles: shallow, deep",
1114                             PARSE_OPT_OPTARG, thread_callback },
1115                 OPT_STRING(0, "signature", &signature, "signature",
1116                             "add a signature"),
1117                 OPT_BOOLEAN(0, "quiet", &quiet,
1118                             "don't print the patch filenames"),
1119                 OPT_END()
1120         };
1121
1122         extra_hdr.strdup_strings = 1;
1123         extra_to.strdup_strings = 1;
1124         extra_cc.strdup_strings = 1;
1125         git_config(git_format_config, NULL);
1126         init_revisions(&rev, prefix);
1127         rev.commit_format = CMIT_FMT_EMAIL;
1128         rev.verbose_header = 1;
1129         rev.diff = 1;
1130         rev.max_parents = 1;
1131         DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
1132         rev.subject_prefix = fmt_patch_subject_prefix;
1133         memset(&s_r_opt, 0, sizeof(s_r_opt));
1134         s_r_opt.def = "HEAD";
1135
1136         if (default_attach) {
1137                 rev.mime_boundary = default_attach;
1138                 rev.no_inline = 1;
1139         }
1140
1141         /*
1142          * Parse the arguments before setup_revisions(), or something
1143          * like "git format-patch -o a123 HEAD^.." may fail; a123 is
1144          * possibly a valid SHA1.
1145          */
1146         argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
1147                              builtin_format_patch_usage,
1148                              PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
1149                              PARSE_OPT_KEEP_DASHDASH);
1150
1151         if (do_signoff) {
1152                 const char *committer;
1153                 const char *endpos;
1154                 committer = git_committer_info(IDENT_STRICT);
1155                 endpos = strchr(committer, '>');
1156                 if (!endpos)
1157                         die(_("bogus committer info %s"), committer);
1158                 add_signoff = xmemdupz(committer, endpos - committer + 1);
1159         }
1160
1161         for (i = 0; i < extra_hdr.nr; i++) {
1162                 strbuf_addstr(&buf, extra_hdr.items[i].string);
1163                 strbuf_addch(&buf, '\n');
1164         }
1165
1166         if (extra_to.nr)
1167                 strbuf_addstr(&buf, "To: ");
1168         for (i = 0; i < extra_to.nr; i++) {
1169                 if (i)
1170                         strbuf_addstr(&buf, "    ");
1171                 strbuf_addstr(&buf, extra_to.items[i].string);
1172                 if (i + 1 < extra_to.nr)
1173                         strbuf_addch(&buf, ',');
1174                 strbuf_addch(&buf, '\n');
1175         }
1176
1177         if (extra_cc.nr)
1178                 strbuf_addstr(&buf, "Cc: ");
1179         for (i = 0; i < extra_cc.nr; i++) {
1180                 if (i)
1181                         strbuf_addstr(&buf, "    ");
1182                 strbuf_addstr(&buf, extra_cc.items[i].string);
1183                 if (i + 1 < extra_cc.nr)
1184                         strbuf_addch(&buf, ',');
1185                 strbuf_addch(&buf, '\n');
1186         }
1187
1188         rev.extra_headers = strbuf_detach(&buf, NULL);
1189
1190         if (start_number < 0)
1191                 start_number = 1;
1192
1193         /*
1194          * If numbered is set solely due to format.numbered in config,
1195          * and it would conflict with --keep-subject (-k) from the
1196          * command line, reset "numbered".
1197          */
1198         if (numbered && keep_subject && !numbered_cmdline_opt)
1199                 numbered = 0;
1200
1201         if (numbered && keep_subject)
1202                 die (_("-n and -k are mutually exclusive."));
1203         if (keep_subject && subject_prefix)
1204                 die (_("--subject-prefix and -k are mutually exclusive."));
1205         rev.preserve_subject = keep_subject;
1206
1207         argc = setup_revisions(argc, argv, &rev, &s_r_opt);
1208         if (argc > 1)
1209                 die (_("unrecognized argument: %s"), argv[1]);
1210
1211         if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
1212                 die(_("--name-only does not make sense"));
1213         if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
1214                 die(_("--name-status does not make sense"));
1215         if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
1216                 die(_("--check does not make sense"));
1217
1218         if (!use_patch_format &&
1219                 (!rev.diffopt.output_format ||
1220                  rev.diffopt.output_format == DIFF_FORMAT_PATCH))
1221                 rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
1222
1223         /* Always generate a patch */
1224         rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
1225
1226         if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
1227                 DIFF_OPT_SET(&rev.diffopt, BINARY);
1228
1229         if (rev.show_notes)
1230                 init_display_notes(&rev.notes_opt);
1231
1232         if (!use_stdout)
1233                 output_directory = set_outdir(prefix, output_directory);
1234         else
1235                 setup_pager();
1236
1237         if (output_directory) {
1238                 if (use_stdout)
1239                         die(_("standard output, or directory, which one?"));
1240                 if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
1241                         die_errno(_("Could not create directory '%s'"),
1242                                   output_directory);
1243         }
1244
1245         if (rev.pending.nr == 1) {
1246                 if (rev.max_count < 0 && !rev.show_root_diff) {
1247                         /*
1248                          * This is traditional behaviour of "git format-patch
1249                          * origin" that prepares what the origin side still
1250                          * does not have.
1251                          */
1252                         unsigned char sha1[20];
1253                         const char *ref;
1254
1255                         rev.pending.objects[0].item->flags |= UNINTERESTING;
1256                         add_head_to_pending(&rev);
1257                         ref = resolve_ref_unsafe("HEAD", sha1, 1, NULL);
1258                         if (ref && !prefixcmp(ref, "refs/heads/"))
1259                                 branch_name = xstrdup(ref + strlen("refs/heads/"));
1260                         else
1261                                 branch_name = xstrdup(""); /* no branch */
1262                 }
1263                 /*
1264                  * Otherwise, it is "format-patch -22 HEAD", and/or
1265                  * "format-patch --root HEAD".  The user wants
1266                  * get_revision() to do the usual traversal.
1267                  */
1268         }
1269
1270         /*
1271          * We cannot move this anywhere earlier because we do want to
1272          * know if --root was given explicitly from the command line.
1273          */
1274         rev.show_root_diff = 1;
1275
1276         if (cover_letter) {
1277                 /*
1278                  * NEEDSWORK:randomly pick one positive commit to show
1279                  * diffstat; this is often the tip and the command
1280                  * happens to do the right thing in most cases, but a
1281                  * complex command like "--cover-letter a b c ^bottom"
1282                  * picks "c" and shows diffstat between bottom..c
1283                  * which may not match what the series represents at
1284                  * all and totally broken.
1285                  */
1286                 int i;
1287                 for (i = 0; i < rev.pending.nr; i++) {
1288                         struct object *o = rev.pending.objects[i].item;
1289                         if (!(o->flags & UNINTERESTING))
1290                                 head = (struct commit *)o;
1291                 }
1292                 /* There is nothing to show; it is not an error, though. */
1293                 if (!head)
1294                         return 0;
1295                 if (!branch_name)
1296                         branch_name = find_branch_name(&rev);
1297         }
1298
1299         if (ignore_if_in_upstream) {
1300                 /* Don't say anything if head and upstream are the same. */
1301                 if (rev.pending.nr == 2) {
1302                         struct object_array_entry *o = rev.pending.objects;
1303                         if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1304                                 return 0;
1305                 }
1306                 get_patch_ids(&rev, &ids, prefix);
1307         }
1308
1309         if (!use_stdout)
1310                 realstdout = xfdopen(xdup(1), "w");
1311
1312         if (prepare_revision_walk(&rev))
1313                 die(_("revision walk setup failed"));
1314         rev.boundary = 1;
1315         while ((commit = get_revision(&rev)) != NULL) {
1316                 if (commit->object.flags & BOUNDARY) {
1317                         boundary_count++;
1318                         origin = (boundary_count == 1) ? commit : NULL;
1319                         continue;
1320                 }
1321
1322                 if (ignore_if_in_upstream &&
1323                                 has_commit_patch_id(commit, &ids))
1324                         continue;
1325
1326                 nr++;
1327                 list = xrealloc(list, nr * sizeof(list[0]));
1328                 list[nr - 1] = commit;
1329         }
1330         total = nr;
1331         if (!keep_subject && auto_number && total > 1)
1332                 numbered = 1;
1333         if (numbered)
1334                 rev.total = total + start_number - 1;
1335         if (in_reply_to || thread || cover_letter)
1336                 rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
1337         if (in_reply_to) {
1338                 const char *msgid = clean_message_id(in_reply_to);
1339                 string_list_append(rev.ref_message_ids, msgid);
1340         }
1341         rev.numbered_files = numbered_files;
1342         rev.patch_suffix = fmt_patch_suffix;
1343         if (cover_letter) {
1344                 if (thread)
1345                         gen_message_id(&rev, "cover");
1346                 make_cover_letter(&rev, use_stdout, numbered, numbered_files,
1347                                   origin, nr, list, head, branch_name, quiet);
1348                 total++;
1349                 start_number--;
1350         }
1351         rev.add_signoff = add_signoff;
1352         while (0 <= --nr) {
1353                 int shown;
1354                 commit = list[nr];
1355                 rev.nr = total - nr + (start_number - 1);
1356                 /* Make the second and subsequent mails replies to the first */
1357                 if (thread) {
1358                         /* Have we already had a message ID? */
1359                         if (rev.message_id) {
1360                                 /*
1361                                  * For deep threading: make every mail
1362                                  * a reply to the previous one, no
1363                                  * matter what other options are set.
1364                                  *
1365                                  * For shallow threading:
1366                                  *
1367                                  * Without --cover-letter and
1368                                  * --in-reply-to, make every mail a
1369                                  * reply to the one before.
1370                                  *
1371                                  * With --in-reply-to but no
1372                                  * --cover-letter, make every mail a
1373                                  * reply to the <reply-to>.
1374                                  *
1375                                  * With --cover-letter, make every
1376                                  * mail but the cover letter a reply
1377                                  * to the cover letter.  The cover
1378                                  * letter is a reply to the
1379                                  * --in-reply-to, if specified.
1380                                  */
1381                                 if (thread == THREAD_SHALLOW
1382                                     && rev.ref_message_ids->nr > 0
1383                                     && (!cover_letter || rev.nr > 1))
1384                                         free(rev.message_id);
1385                                 else
1386                                         string_list_append(rev.ref_message_ids,
1387                                                            rev.message_id);
1388                         }
1389                         gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
1390                 }
1391
1392                 if (!use_stdout &&
1393                     reopen_stdout(numbered_files ? NULL : commit, NULL, &rev, quiet))
1394                         die(_("Failed to create output files"));
1395                 shown = log_tree_commit(&rev, commit);
1396                 free(commit->buffer);
1397                 commit->buffer = NULL;
1398
1399                 /* We put one extra blank line between formatted
1400                  * patches and this flag is used by log-tree code
1401                  * to see if it needs to emit a LF before showing
1402                  * the log; when using one file per patch, we do
1403                  * not want the extra blank line.
1404                  */
1405                 if (!use_stdout)
1406                         rev.shown_one = 0;
1407                 if (shown) {
1408                         if (rev.mime_boundary)
1409                                 printf("\n--%s%s--\n\n\n",
1410                                        mime_boundary_leader,
1411                                        rev.mime_boundary);
1412                         else
1413                                 print_signature();
1414                 }
1415                 if (!use_stdout)
1416                         fclose(stdout);
1417         }
1418         free(list);
1419         free(branch_name);
1420         string_list_clear(&extra_to, 0);
1421         string_list_clear(&extra_cc, 0);
1422         string_list_clear(&extra_hdr, 0);
1423         if (ignore_if_in_upstream)
1424                 free_patch_ids(&ids);
1425         return 0;
1426 }
1427
1428 static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
1429 {
1430         unsigned char sha1[20];
1431         if (get_sha1(arg, sha1) == 0) {
1432                 struct commit *commit = lookup_commit_reference(sha1);
1433                 if (commit) {
1434                         commit->object.flags |= flags;
1435                         add_pending_object(revs, &commit->object, arg);
1436                         return 0;
1437                 }
1438         }
1439         return -1;
1440 }
1441
1442 static const char * const cherry_usage[] = {
1443         "git cherry [-v] [<upstream> [<head> [<limit>]]]",
1444         NULL
1445 };
1446
1447 static void print_commit(char sign, struct commit *commit, int verbose,
1448                          int abbrev)
1449 {
1450         if (!verbose) {
1451                 printf("%c %s\n", sign,
1452                        find_unique_abbrev(commit->object.sha1, abbrev));
1453         } else {
1454                 struct strbuf buf = STRBUF_INIT;
1455                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
1456                 printf("%c %s %s\n", sign,
1457                        find_unique_abbrev(commit->object.sha1, abbrev),
1458                        buf.buf);
1459                 strbuf_release(&buf);
1460         }
1461 }
1462
1463 int cmd_cherry(int argc, const char **argv, const char *prefix)
1464 {
1465         struct rev_info revs;
1466         struct patch_ids ids;
1467         struct commit *commit;
1468         struct commit_list *list = NULL;
1469         struct branch *current_branch;
1470         const char *upstream;
1471         const char *head = "HEAD";
1472         const char *limit = NULL;
1473         int verbose = 0, abbrev = 0;
1474
1475         struct option options[] = {
1476                 OPT__ABBREV(&abbrev),
1477                 OPT__VERBOSE(&verbose, "be verbose"),
1478                 OPT_END()
1479         };
1480
1481         argc = parse_options(argc, argv, prefix, options, cherry_usage, 0);
1482
1483         switch (argc) {
1484         case 3:
1485                 limit = argv[2];
1486                 /* FALLTHROUGH */
1487         case 2:
1488                 head = argv[1];
1489                 /* FALLTHROUGH */
1490         case 1:
1491                 upstream = argv[0];
1492                 break;
1493         default:
1494                 current_branch = branch_get(NULL);
1495                 if (!current_branch || !current_branch->merge
1496                                         || !current_branch->merge[0]
1497                                         || !current_branch->merge[0]->dst) {
1498                         fprintf(stderr, _("Could not find a tracked"
1499                                         " remote branch, please"
1500                                         " specify <upstream> manually.\n"));
1501                         usage_with_options(cherry_usage, options);
1502                 }
1503
1504                 upstream = current_branch->merge[0]->dst;
1505         }
1506
1507         init_revisions(&revs, prefix);
1508         revs.diff = 1;
1509         revs.combine_merges = 0;
1510         revs.ignore_merges = 1;
1511         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1512
1513         if (add_pending_commit(head, &revs, 0))
1514                 die(_("Unknown commit %s"), head);
1515         if (add_pending_commit(upstream, &revs, UNINTERESTING))
1516                 die(_("Unknown commit %s"), upstream);
1517
1518         /* Don't say anything if head and upstream are the same. */
1519         if (revs.pending.nr == 2) {
1520                 struct object_array_entry *o = revs.pending.objects;
1521                 if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
1522                         return 0;
1523         }
1524
1525         get_patch_ids(&revs, &ids, prefix);
1526
1527         if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
1528                 die(_("Unknown commit %s"), limit);
1529
1530         /* reverse the list of commits */
1531         if (prepare_revision_walk(&revs))
1532                 die(_("revision walk setup failed"));
1533         while ((commit = get_revision(&revs)) != NULL) {
1534                 /* ignore merges */
1535                 if (commit->parents && commit->parents->next)
1536                         continue;
1537
1538                 commit_list_insert(commit, &list);
1539         }
1540
1541         while (list) {
1542                 char sign = '+';
1543
1544                 commit = list->item;
1545                 if (has_commit_patch_id(commit, &ids))
1546                         sign = '-';
1547                 print_commit(sign, commit, verbose, abbrev);
1548                 list = list->next;
1549         }
1550
1551         free_patch_ids(&ids);
1552         return 0;
1553 }