Merge branch 'rf/maint-mailmap-off-by-one' into maint
[git] / builtin / fmt-merge-msg.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "commit.h"
4 #include "diff.h"
5 #include "revision.h"
6 #include "tag.h"
7 #include "string-list.h"
8 #include "branch.h"
9 #include "fmt-merge-msg.h"
10 #include "gpg-interface.h"
11
12 static const char * const fmt_merge_msg_usage[] = {
13         N_("git fmt-merge-msg [-m <message>] [--log[=<n>]|--no-log] [--file <file>]"),
14         NULL
15 };
16
17 static int use_branch_desc;
18
19 int fmt_merge_msg_config(const char *key, const char *value, void *cb)
20 {
21         if (!strcmp(key, "merge.log") || !strcmp(key, "merge.summary")) {
22                 int is_bool;
23                 merge_log_config = git_config_bool_or_int(key, value, &is_bool);
24                 if (!is_bool && merge_log_config < 0)
25                         return error("%s: negative length %s", key, value);
26                 if (is_bool && merge_log_config)
27                         merge_log_config = DEFAULT_MERGE_LOG_LEN;
28         } else if (!strcmp(key, "merge.branchdesc")) {
29                 use_branch_desc = git_config_bool(key, value);
30         } else {
31                 return git_default_config(key, value, cb);
32         }
33         return 0;
34 }
35
36 /* merge data per repository where the merged tips came from */
37 struct src_data {
38         struct string_list branch, tag, r_branch, generic;
39         int head_status;
40 };
41
42 struct origin_data {
43         unsigned char sha1[20];
44         unsigned is_local_branch:1;
45 };
46
47 static void init_src_data(struct src_data *data)
48 {
49         data->branch.strdup_strings = 1;
50         data->tag.strdup_strings = 1;
51         data->r_branch.strdup_strings = 1;
52         data->generic.strdup_strings = 1;
53 }
54
55 static struct string_list srcs = STRING_LIST_INIT_DUP;
56 static struct string_list origins = STRING_LIST_INIT_DUP;
57
58 struct merge_parents {
59         int alloc, nr;
60         struct merge_parent {
61                 unsigned char given[20];
62                 unsigned char commit[20];
63                 unsigned char used;
64         } *item;
65 };
66
67 /*
68  * I know, I know, this is inefficient, but you won't be pulling and merging
69  * hundreds of heads at a time anyway.
70  */
71 static struct merge_parent *find_merge_parent(struct merge_parents *table,
72                                               unsigned char *given,
73                                               unsigned char *commit)
74 {
75         int i;
76         for (i = 0; i < table->nr; i++) {
77                 if (given && hashcmp(table->item[i].given, given))
78                         continue;
79                 if (commit && hashcmp(table->item[i].commit, commit))
80                         continue;
81                 return &table->item[i];
82         }
83         return NULL;
84 }
85
86 static void add_merge_parent(struct merge_parents *table,
87                              unsigned char *given,
88                              unsigned char *commit)
89 {
90         if (table->nr && find_merge_parent(table, given, commit))
91                 return;
92         ALLOC_GROW(table->item, table->nr + 1, table->alloc);
93         hashcpy(table->item[table->nr].given, given);
94         hashcpy(table->item[table->nr].commit, commit);
95         table->item[table->nr].used = 0;
96         table->nr++;
97 }
98
99 static int handle_line(char *line, struct merge_parents *merge_parents)
100 {
101         int i, len = strlen(line);
102         struct origin_data *origin_data;
103         char *src, *origin;
104         struct src_data *src_data;
105         struct string_list_item *item;
106         int pulling_head = 0;
107         unsigned char sha1[20];
108
109         if (len < 43 || line[40] != '\t')
110                 return 1;
111
112         if (!prefixcmp(line + 41, "not-for-merge"))
113                 return 0;
114
115         if (line[41] != '\t')
116                 return 2;
117
118         i = get_sha1_hex(line, sha1);
119         if (i)
120                 return 3;
121
122         if (!find_merge_parent(merge_parents, sha1, NULL))
123                 return 0; /* subsumed by other parents */
124
125         origin_data = xcalloc(1, sizeof(struct origin_data));
126         hashcpy(origin_data->sha1, sha1);
127
128         if (line[len - 1] == '\n')
129                 line[len - 1] = 0;
130         line += 42;
131
132         /*
133          * At this point, line points at the beginning of comment e.g.
134          * "branch 'frotz' of git://that/repository.git".
135          * Find the repository name and point it with src.
136          */
137         src = strstr(line, " of ");
138         if (src) {
139                 *src = 0;
140                 src += 4;
141                 pulling_head = 0;
142         } else {
143                 src = line;
144                 pulling_head = 1;
145         }
146
147         item = unsorted_string_list_lookup(&srcs, src);
148         if (!item) {
149                 item = string_list_append(&srcs, src);
150                 item->util = xcalloc(1, sizeof(struct src_data));
151                 init_src_data(item->util);
152         }
153         src_data = item->util;
154
155         if (pulling_head) {
156                 origin = src;
157                 src_data->head_status |= 1;
158         } else if (!prefixcmp(line, "branch ")) {
159                 origin_data->is_local_branch = 1;
160                 origin = line + 7;
161                 string_list_append(&src_data->branch, origin);
162                 src_data->head_status |= 2;
163         } else if (!prefixcmp(line, "tag ")) {
164                 origin = line;
165                 string_list_append(&src_data->tag, origin + 4);
166                 src_data->head_status |= 2;
167         } else if (!prefixcmp(line, "remote-tracking branch ")) {
168                 origin = line + strlen("remote-tracking branch ");
169                 string_list_append(&src_data->r_branch, origin);
170                 src_data->head_status |= 2;
171         } else {
172                 origin = src;
173                 string_list_append(&src_data->generic, line);
174                 src_data->head_status |= 2;
175         }
176
177         if (!strcmp(".", src) || !strcmp(src, origin)) {
178                 int len = strlen(origin);
179                 if (origin[0] == '\'' && origin[len - 1] == '\'')
180                         origin = xmemdupz(origin + 1, len - 2);
181         } else {
182                 char *new_origin = xmalloc(strlen(origin) + strlen(src) + 5);
183                 sprintf(new_origin, "%s of %s", origin, src);
184                 origin = new_origin;
185         }
186         if (strcmp(".", src))
187                 origin_data->is_local_branch = 0;
188         string_list_append(&origins, origin)->util = origin_data;
189         return 0;
190 }
191
192 static void print_joined(const char *singular, const char *plural,
193                 struct string_list *list, struct strbuf *out)
194 {
195         if (list->nr == 0)
196                 return;
197         if (list->nr == 1) {
198                 strbuf_addf(out, "%s%s", singular, list->items[0].string);
199         } else {
200                 int i;
201                 strbuf_addstr(out, plural);
202                 for (i = 0; i < list->nr - 1; i++)
203                         strbuf_addf(out, "%s%s", i > 0 ? ", " : "",
204                                     list->items[i].string);
205                 strbuf_addf(out, " and %s", list->items[list->nr - 1].string);
206         }
207 }
208
209 static void add_branch_desc(struct strbuf *out, const char *name)
210 {
211         struct strbuf desc = STRBUF_INIT;
212
213         if (!read_branch_desc(&desc, name)) {
214                 const char *bp = desc.buf;
215                 while (*bp) {
216                         const char *ep = strchrnul(bp, '\n');
217                         if (*ep)
218                                 ep++;
219                         strbuf_addf(out, "  : %.*s", (int)(ep - bp), bp);
220                         bp = ep;
221                 }
222                 if (out->buf[out->len - 1] != '\n')
223                         strbuf_addch(out, '\n');
224         }
225         strbuf_release(&desc);
226 }
227
228 #define util_as_integral(elem) ((intptr_t)((elem)->util))
229
230 static void record_person(int which, struct string_list *people,
231                           struct commit *commit)
232 {
233         char *name_buf, *name, *name_end;
234         struct string_list_item *elem;
235         const char *field = (which == 'a') ? "\nauthor " : "\ncommitter ";
236
237         name = strstr(commit->buffer, field);
238         if (!name)
239                 return;
240         name += strlen(field);
241         name_end = strchrnul(name, '<');
242         if (*name_end)
243                 name_end--;
244         while (isspace(*name_end) && name <= name_end)
245                 name_end--;
246         if (name_end < name)
247                 return;
248         name_buf = xmemdupz(name, name_end - name + 1);
249
250         elem = string_list_lookup(people, name_buf);
251         if (!elem) {
252                 elem = string_list_insert(people, name_buf);
253                 elem->util = (void *)0;
254         }
255         elem->util = (void*)(util_as_integral(elem) + 1);
256         free(name_buf);
257 }
258
259 static int cmp_string_list_util_as_integral(const void *a_, const void *b_)
260 {
261         const struct string_list_item *a = a_, *b = b_;
262         return util_as_integral(b) - util_as_integral(a);
263 }
264
265 static void add_people_count(struct strbuf *out, struct string_list *people)
266 {
267         if (people->nr == 1)
268                 strbuf_addf(out, "%s", people->items[0].string);
269         else if (people->nr == 2)
270                 strbuf_addf(out, "%s (%d) and %s (%d)",
271                             people->items[0].string,
272                             (int)util_as_integral(&people->items[0]),
273                             people->items[1].string,
274                             (int)util_as_integral(&people->items[1]));
275         else if (people->nr)
276                 strbuf_addf(out, "%s (%d) and others",
277                             people->items[0].string,
278                             (int)util_as_integral(&people->items[0]));
279 }
280
281 static void credit_people(struct strbuf *out,
282                           struct string_list *them,
283                           int kind)
284 {
285         const char *label;
286         const char *me;
287
288         if (kind == 'a') {
289                 label = "\n# By ";
290                 me = git_author_info(IDENT_NO_DATE);
291         } else {
292                 label = "\n# Via ";
293                 me = git_committer_info(IDENT_NO_DATE);
294         }
295
296         if (!them->nr ||
297             (them->nr == 1 &&
298              me &&
299              (me = skip_prefix(me, them->items->string)) != NULL &&
300              skip_prefix(me, " <")))
301                 return;
302         strbuf_addstr(out, label);
303         add_people_count(out, them);
304 }
305
306 static void add_people_info(struct strbuf *out,
307                             struct string_list *authors,
308                             struct string_list *committers)
309 {
310         if (authors->nr)
311                 qsort(authors->items,
312                       authors->nr, sizeof(authors->items[0]),
313                       cmp_string_list_util_as_integral);
314         if (committers->nr)
315                 qsort(committers->items,
316                       committers->nr, sizeof(committers->items[0]),
317                       cmp_string_list_util_as_integral);
318
319         credit_people(out, authors, 'a');
320         credit_people(out, committers, 'c');
321 }
322
323 static void shortlog(const char *name,
324                      struct origin_data *origin_data,
325                      struct commit *head,
326                      struct rev_info *rev, int limit,
327                      struct strbuf *out)
328 {
329         int i, count = 0;
330         struct commit *commit;
331         struct object *branch;
332         struct string_list subjects = STRING_LIST_INIT_DUP;
333         struct string_list authors = STRING_LIST_INIT_DUP;
334         struct string_list committers = STRING_LIST_INIT_DUP;
335         int flags = UNINTERESTING | TREESAME | SEEN | SHOWN | ADDED;
336         struct strbuf sb = STRBUF_INIT;
337         const unsigned char *sha1 = origin_data->sha1;
338
339         branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
340         if (!branch || branch->type != OBJ_COMMIT)
341                 return;
342
343         setup_revisions(0, NULL, rev, NULL);
344         add_pending_object(rev, branch, name);
345         add_pending_object(rev, &head->object, "^HEAD");
346         head->object.flags |= UNINTERESTING;
347         if (prepare_revision_walk(rev))
348                 die("revision walk setup failed");
349         while ((commit = get_revision(rev)) != NULL) {
350                 struct pretty_print_context ctx = {0};
351
352                 if (commit->parents && commit->parents->next) {
353                         /* do not list a merge but count committer */
354                         record_person('c', &committers, commit);
355                         continue;
356                 }
357                 if (!count)
358                         /* the 'tip' committer */
359                         record_person('c', &committers, commit);
360                 record_person('a', &authors, commit);
361                 count++;
362                 if (subjects.nr > limit)
363                         continue;
364
365                 format_commit_message(commit, "%s", &sb, &ctx);
366                 strbuf_ltrim(&sb);
367
368                 if (!sb.len)
369                         string_list_append(&subjects,
370                                            sha1_to_hex(commit->object.sha1));
371                 else
372                         string_list_append(&subjects, strbuf_detach(&sb, NULL));
373         }
374
375         add_people_info(out, &authors, &committers);
376         if (count > limit)
377                 strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
378         else
379                 strbuf_addf(out, "\n* %s:\n", name);
380
381         if (origin_data->is_local_branch && use_branch_desc)
382                 add_branch_desc(out, name);
383
384         for (i = 0; i < subjects.nr; i++)
385                 if (i >= limit)
386                         strbuf_addf(out, "  ...\n");
387                 else
388                         strbuf_addf(out, "  %s\n", subjects.items[i].string);
389
390         clear_commit_marks((struct commit *)branch, flags);
391         clear_commit_marks(head, flags);
392         free_commit_list(rev->commits);
393         rev->commits = NULL;
394         rev->pending.nr = 0;
395
396         string_list_clear(&authors, 0);
397         string_list_clear(&committers, 0);
398         string_list_clear(&subjects, 0);
399 }
400
401 static void fmt_merge_msg_title(struct strbuf *out,
402         const char *current_branch) {
403         int i = 0;
404         char *sep = "";
405
406         strbuf_addstr(out, "Merge ");
407         for (i = 0; i < srcs.nr; i++) {
408                 struct src_data *src_data = srcs.items[i].util;
409                 const char *subsep = "";
410
411                 strbuf_addstr(out, sep);
412                 sep = "; ";
413
414                 if (src_data->head_status == 1) {
415                         strbuf_addstr(out, srcs.items[i].string);
416                         continue;
417                 }
418                 if (src_data->head_status == 3) {
419                         subsep = ", ";
420                         strbuf_addstr(out, "HEAD");
421                 }
422                 if (src_data->branch.nr) {
423                         strbuf_addstr(out, subsep);
424                         subsep = ", ";
425                         print_joined("branch ", "branches ", &src_data->branch,
426                                         out);
427                 }
428                 if (src_data->r_branch.nr) {
429                         strbuf_addstr(out, subsep);
430                         subsep = ", ";
431                         print_joined("remote-tracking branch ", "remote-tracking branches ",
432                                         &src_data->r_branch, out);
433                 }
434                 if (src_data->tag.nr) {
435                         strbuf_addstr(out, subsep);
436                         subsep = ", ";
437                         print_joined("tag ", "tags ", &src_data->tag, out);
438                 }
439                 if (src_data->generic.nr) {
440                         strbuf_addstr(out, subsep);
441                         print_joined("commit ", "commits ", &src_data->generic,
442                                         out);
443                 }
444                 if (strcmp(".", srcs.items[i].string))
445                         strbuf_addf(out, " of %s", srcs.items[i].string);
446         }
447
448         if (!strcmp("master", current_branch))
449                 strbuf_addch(out, '\n');
450         else
451                 strbuf_addf(out, " into %s\n", current_branch);
452 }
453
454 static void fmt_tag_signature(struct strbuf *tagbuf,
455                               struct strbuf *sig,
456                               const char *buf,
457                               unsigned long len)
458 {
459         const char *tag_body = strstr(buf, "\n\n");
460         if (tag_body) {
461                 tag_body += 2;
462                 strbuf_add(tagbuf, tag_body, buf + len - tag_body);
463         }
464         strbuf_complete_line(tagbuf);
465         if (sig->len) {
466                 strbuf_addch(tagbuf, '\n');
467                 strbuf_add_lines(tagbuf, "# ", sig->buf, sig->len);
468         }
469 }
470
471 static void fmt_merge_msg_sigs(struct strbuf *out)
472 {
473         int i, tag_number = 0, first_tag = 0;
474         struct strbuf tagbuf = STRBUF_INIT;
475
476         for (i = 0; i < origins.nr; i++) {
477                 unsigned char *sha1 = origins.items[i].util;
478                 enum object_type type;
479                 unsigned long size, len;
480                 char *buf = read_sha1_file(sha1, &type, &size);
481                 struct strbuf sig = STRBUF_INIT;
482
483                 if (!buf || type != OBJ_TAG)
484                         goto next;
485                 len = parse_signature(buf, size);
486
487                 if (size == len)
488                         ; /* merely annotated */
489                 else if (verify_signed_buffer(buf, len, buf + len, size - len, &sig)) {
490                         if (!sig.len)
491                                 strbuf_addstr(&sig, "gpg verification failed.\n");
492                 }
493
494                 if (!tag_number++) {
495                         fmt_tag_signature(&tagbuf, &sig, buf, len);
496                         first_tag = i;
497                 } else {
498                         if (tag_number == 2) {
499                                 struct strbuf tagline = STRBUF_INIT;
500                                 strbuf_addf(&tagline, "\n# %s\n",
501                                             origins.items[first_tag].string);
502                                 strbuf_insert(&tagbuf, 0, tagline.buf,
503                                               tagline.len);
504                                 strbuf_release(&tagline);
505                         }
506                         strbuf_addf(&tagbuf, "\n# %s\n",
507                                     origins.items[i].string);
508                         fmt_tag_signature(&tagbuf, &sig, buf, len);
509                 }
510                 strbuf_release(&sig);
511         next:
512                 free(buf);
513         }
514         if (tagbuf.len) {
515                 strbuf_addch(out, '\n');
516                 strbuf_addbuf(out, &tagbuf);
517         }
518         strbuf_release(&tagbuf);
519 }
520
521 static void find_merge_parents(struct merge_parents *result,
522                                struct strbuf *in, unsigned char *head)
523 {
524         struct commit_list *parents, *next;
525         struct commit *head_commit;
526         int pos = 0, i, j;
527
528         parents = NULL;
529         while (pos < in->len) {
530                 int len;
531                 char *p = in->buf + pos;
532                 char *newline = strchr(p, '\n');
533                 unsigned char sha1[20];
534                 struct commit *parent;
535                 struct object *obj;
536
537                 len = newline ? newline - p : strlen(p);
538                 pos += len + !!newline;
539
540                 if (len < 43 ||
541                     get_sha1_hex(p, sha1) ||
542                     p[40] != '\t' ||
543                     p[41] != '\t')
544                         continue; /* skip not-for-merge */
545                 /*
546                  * Do not use get_merge_parent() here; we do not have
547                  * "name" here and we do not want to contaminate its
548                  * util field yet.
549                  */
550                 obj = parse_object(sha1);
551                 parent = (struct commit *)peel_to_type(NULL, 0, obj, OBJ_COMMIT);
552                 if (!parent)
553                         continue;
554                 commit_list_insert(parent, &parents);
555                 add_merge_parent(result, obj->sha1, parent->object.sha1);
556         }
557         head_commit = lookup_commit(head);
558         if (head_commit)
559                 commit_list_insert(head_commit, &parents);
560         parents = reduce_heads(parents);
561
562         while (parents) {
563                 for (i = 0; i < result->nr; i++)
564                         if (!hashcmp(result->item[i].commit,
565                                      parents->item->object.sha1))
566                                 result->item[i].used = 1;
567                 next = parents->next;
568                 free(parents);
569                 parents = next;
570         }
571
572         for (i = j = 0; i < result->nr; i++) {
573                 if (result->item[i].used) {
574                         if (i != j)
575                                 result->item[j] = result->item[i];
576                         j++;
577                 }
578         }
579         result->nr = j;
580 }
581
582 int fmt_merge_msg(struct strbuf *in, struct strbuf *out,
583                   struct fmt_merge_msg_opts *opts)
584 {
585         int i = 0, pos = 0;
586         unsigned char head_sha1[20];
587         const char *current_branch;
588         void *current_branch_to_free;
589         struct merge_parents merge_parents;
590
591         memset(&merge_parents, 0, sizeof(merge_parents));
592
593         /* get current branch */
594         current_branch = current_branch_to_free =
595                 resolve_refdup("HEAD", head_sha1, 1, NULL);
596         if (!current_branch)
597                 die("No current branch");
598         if (!prefixcmp(current_branch, "refs/heads/"))
599                 current_branch += 11;
600
601         find_merge_parents(&merge_parents, in, head_sha1);
602
603         /* get a line */
604         while (pos < in->len) {
605                 int len;
606                 char *newline, *p = in->buf + pos;
607
608                 newline = strchr(p, '\n');
609                 len = newline ? newline - p : strlen(p);
610                 pos += len + !!newline;
611                 i++;
612                 p[len] = 0;
613                 if (handle_line(p, &merge_parents))
614                         die ("Error in line %d: %.*s", i, len, p);
615         }
616
617         if (opts->add_title && srcs.nr)
618                 fmt_merge_msg_title(out, current_branch);
619
620         if (origins.nr)
621                 fmt_merge_msg_sigs(out);
622
623         if (opts->shortlog_len) {
624                 struct commit *head;
625                 struct rev_info rev;
626
627                 head = lookup_commit_or_die(head_sha1, "HEAD");
628                 init_revisions(&rev, NULL);
629                 rev.commit_format = CMIT_FMT_ONELINE;
630                 rev.ignore_merges = 1;
631                 rev.limited = 1;
632
633                 strbuf_complete_line(out);
634
635                 for (i = 0; i < origins.nr; i++)
636                         shortlog(origins.items[i].string,
637                                  origins.items[i].util,
638                                  head, &rev, opts->shortlog_len, out);
639         }
640
641         strbuf_complete_line(out);
642         free(current_branch_to_free);
643         free(merge_parents.item);
644         return 0;
645 }
646
647 int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
648 {
649         const char *inpath = NULL;
650         const char *message = NULL;
651         int shortlog_len = -1;
652         struct option options[] = {
653                 { OPTION_INTEGER, 0, "log", &shortlog_len, N_("n"),
654                   N_("populate log with at most <n> entries from shortlog"),
655                   PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
656                 { OPTION_INTEGER, 0, "summary", &shortlog_len, N_("n"),
657                   N_("alias for --log (deprecated)"),
658                   PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, NULL,
659                   DEFAULT_MERGE_LOG_LEN },
660                 OPT_STRING('m', "message", &message, N_("text"),
661                         N_("use <text> as start of message")),
662                 OPT_FILENAME('F', "file", &inpath, N_("file to read from")),
663                 OPT_END()
664         };
665
666         FILE *in = stdin;
667         struct strbuf input = STRBUF_INIT, output = STRBUF_INIT;
668         int ret;
669         struct fmt_merge_msg_opts opts;
670
671         git_config(fmt_merge_msg_config, NULL);
672         argc = parse_options(argc, argv, prefix, options, fmt_merge_msg_usage,
673                              0);
674         if (argc > 0)
675                 usage_with_options(fmt_merge_msg_usage, options);
676         if (shortlog_len < 0)
677                 shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
678
679         if (inpath && strcmp(inpath, "-")) {
680                 in = fopen(inpath, "r");
681                 if (!in)
682                         die_errno("cannot open '%s'", inpath);
683         }
684
685         if (strbuf_read(&input, fileno(in), 0) < 0)
686                 die_errno("could not read input file");
687
688         if (message)
689                 strbuf_addstr(&output, message);
690
691         memset(&opts, 0, sizeof(opts));
692         opts.add_title = !message;
693         opts.shortlog_len = shortlog_len;
694
695         ret = fmt_merge_msg(&input, &output, &opts);
696         if (ret)
697                 return ret;
698         write_in_full(STDOUT_FILENO, output.buf, output.len);
699         return 0;
700 }