Merge gitk to pick up emergency build fix
[git] / builtin / fmt-merge-msg.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "config.h"
4 #include "refs.h"
5 #include "object-store.h"
6 #include "commit.h"
7 #include "diff.h"
8 #include "revision.h"
9 #include "tag.h"
10 #include "string-list.h"
11 #include "branch.h"
12 #include "fmt-merge-msg.h"
13 #include "gpg-interface.h"
14 #include "repository.h"
15 #include "commit-reach.h"
16
17 static const char * const fmt_merge_msg_usage[] = {
18         N_("git fmt-merge-msg [-m <message>] [--log[=<n>] | --no-log] [--file <file>]"),
19         NULL
20 };
21
22 static int use_branch_desc;
23
24 int fmt_merge_msg_config(const char *key, const char *value, void *cb)
25 {
26         if (!strcmp(key, "merge.log") || !strcmp(key, "merge.summary")) {
27                 int is_bool;
28                 merge_log_config = git_config_bool_or_int(key, value, &is_bool);
29                 if (!is_bool && merge_log_config < 0)
30                         return error("%s: negative length %s", key, value);
31                 if (is_bool && merge_log_config)
32                         merge_log_config = DEFAULT_MERGE_LOG_LEN;
33         } else if (!strcmp(key, "merge.branchdesc")) {
34                 use_branch_desc = git_config_bool(key, value);
35         } else {
36                 return git_default_config(key, value, cb);
37         }
38         return 0;
39 }
40
41 /* merge data per repository where the merged tips came from */
42 struct src_data {
43         struct string_list branch, tag, r_branch, generic;
44         int head_status;
45 };
46
47 struct origin_data {
48         struct object_id oid;
49         unsigned is_local_branch:1;
50 };
51
52 static void init_src_data(struct src_data *data)
53 {
54         data->branch.strdup_strings = 1;
55         data->tag.strdup_strings = 1;
56         data->r_branch.strdup_strings = 1;
57         data->generic.strdup_strings = 1;
58 }
59
60 static struct string_list srcs = STRING_LIST_INIT_DUP;
61 static struct string_list origins = STRING_LIST_INIT_DUP;
62
63 struct merge_parents {
64         int alloc, nr;
65         struct merge_parent {
66                 struct object_id given;
67                 struct object_id commit;
68                 unsigned char used;
69         } *item;
70 };
71
72 /*
73  * I know, I know, this is inefficient, but you won't be pulling and merging
74  * hundreds of heads at a time anyway.
75  */
76 static struct merge_parent *find_merge_parent(struct merge_parents *table,
77                                               struct object_id *given,
78                                               struct object_id *commit)
79 {
80         int i;
81         for (i = 0; i < table->nr; i++) {
82                 if (given && !oideq(&table->item[i].given, given))
83                         continue;
84                 if (commit && !oideq(&table->item[i].commit, commit))
85                         continue;
86                 return &table->item[i];
87         }
88         return NULL;
89 }
90
91 static void add_merge_parent(struct merge_parents *table,
92                              struct object_id *given,
93                              struct object_id *commit)
94 {
95         if (table->nr && find_merge_parent(table, given, commit))
96                 return;
97         ALLOC_GROW(table->item, table->nr + 1, table->alloc);
98         oidcpy(&table->item[table->nr].given, given);
99         oidcpy(&table->item[table->nr].commit, commit);
100         table->item[table->nr].used = 0;
101         table->nr++;
102 }
103
104 static int handle_line(char *line, struct merge_parents *merge_parents)
105 {
106         int i, len = strlen(line);
107         struct origin_data *origin_data;
108         char *src;
109         const char *origin;
110         struct src_data *src_data;
111         struct string_list_item *item;
112         int pulling_head = 0;
113         struct object_id oid;
114         const unsigned hexsz = the_hash_algo->hexsz;
115
116         if (len < hexsz + 3 || line[hexsz] != '\t')
117                 return 1;
118
119         if (starts_with(line + hexsz + 1, "not-for-merge"))
120                 return 0;
121
122         if (line[hexsz + 1] != '\t')
123                 return 2;
124
125         i = get_oid_hex(line, &oid);
126         if (i)
127                 return 3;
128
129         if (!find_merge_parent(merge_parents, &oid, NULL))
130                 return 0; /* subsumed by other parents */
131
132         origin_data = xcalloc(1, sizeof(struct origin_data));
133         oidcpy(&origin_data->oid, &oid);
134
135         if (line[len - 1] == '\n')
136                 line[len - 1] = 0;
137         line += hexsz + 2;
138
139         /*
140          * At this point, line points at the beginning of comment e.g.
141          * "branch 'frotz' of git://that/repository.git".
142          * Find the repository name and point it with src.
143          */
144         src = strstr(line, " of ");
145         if (src) {
146                 *src = 0;
147                 src += 4;
148                 pulling_head = 0;
149         } else {
150                 src = line;
151                 pulling_head = 1;
152         }
153
154         item = unsorted_string_list_lookup(&srcs, src);
155         if (!item) {
156                 item = string_list_append(&srcs, src);
157                 item->util = xcalloc(1, sizeof(struct src_data));
158                 init_src_data(item->util);
159         }
160         src_data = item->util;
161
162         if (pulling_head) {
163                 origin = src;
164                 src_data->head_status |= 1;
165         } else if (starts_with(line, "branch ")) {
166                 origin_data->is_local_branch = 1;
167                 origin = line + 7;
168                 string_list_append(&src_data->branch, origin);
169                 src_data->head_status |= 2;
170         } else if (starts_with(line, "tag ")) {
171                 origin = line;
172                 string_list_append(&src_data->tag, origin + 4);
173                 src_data->head_status |= 2;
174         } else if (skip_prefix(line, "remote-tracking branch ", &origin)) {
175                 string_list_append(&src_data->r_branch, origin);
176                 src_data->head_status |= 2;
177         } else {
178                 origin = src;
179                 string_list_append(&src_data->generic, line);
180                 src_data->head_status |= 2;
181         }
182
183         if (!strcmp(".", src) || !strcmp(src, origin)) {
184                 int len = strlen(origin);
185                 if (origin[0] == '\'' && origin[len - 1] == '\'')
186                         origin = xmemdupz(origin + 1, len - 2);
187         } else
188                 origin = xstrfmt("%s of %s", origin, src);
189         if (strcmp(".", src))
190                 origin_data->is_local_branch = 0;
191         string_list_append(&origins, origin)->util = origin_data;
192         return 0;
193 }
194
195 static void print_joined(const char *singular, const char *plural,
196                 struct string_list *list, struct strbuf *out)
197 {
198         if (list->nr == 0)
199                 return;
200         if (list->nr == 1) {
201                 strbuf_addf(out, "%s%s", singular, list->items[0].string);
202         } else {
203                 int i;
204                 strbuf_addstr(out, plural);
205                 for (i = 0; i < list->nr - 1; i++)
206                         strbuf_addf(out, "%s%s", i > 0 ? ", " : "",
207                                     list->items[i].string);
208                 strbuf_addf(out, " and %s", list->items[list->nr - 1].string);
209         }
210 }
211
212 static void add_branch_desc(struct strbuf *out, const char *name)
213 {
214         struct strbuf desc = STRBUF_INIT;
215
216         if (!read_branch_desc(&desc, name)) {
217                 const char *bp = desc.buf;
218                 while (*bp) {
219                         const char *ep = strchrnul(bp, '\n');
220                         if (*ep)
221                                 ep++;
222                         strbuf_addf(out, "  : %.*s", (int)(ep - bp), bp);
223                         bp = ep;
224                 }
225                 strbuf_complete_line(out);
226         }
227         strbuf_release(&desc);
228 }
229
230 #define util_as_integral(elem) ((intptr_t)((elem)->util))
231
232 static void record_person_from_buf(int which, struct string_list *people,
233                                    const char *buffer)
234 {
235         char *name_buf, *name, *name_end;
236         struct string_list_item *elem;
237         const char *field;
238
239         field = (which == 'a') ? "\nauthor " : "\ncommitter ";
240         name = strstr(buffer, field);
241         if (!name)
242                 return;
243         name += strlen(field);
244         name_end = strchrnul(name, '<');
245         if (*name_end)
246                 name_end--;
247         while (isspace(*name_end) && name <= name_end)
248                 name_end--;
249         if (name_end < name)
250                 return;
251         name_buf = xmemdupz(name, name_end - name + 1);
252
253         elem = string_list_lookup(people, name_buf);
254         if (!elem) {
255                 elem = string_list_insert(people, name_buf);
256                 elem->util = (void *)0;
257         }
258         elem->util = (void*)(util_as_integral(elem) + 1);
259         free(name_buf);
260 }
261
262
263 static void record_person(int which, struct string_list *people,
264                           struct commit *commit)
265 {
266         const char *buffer = get_commit_buffer(commit, NULL);
267         record_person_from_buf(which, people, buffer);
268         unuse_commit_buffer(commit, buffer);
269 }
270
271 static int cmp_string_list_util_as_integral(const void *a_, const void *b_)
272 {
273         const struct string_list_item *a = a_, *b = b_;
274         return util_as_integral(b) - util_as_integral(a);
275 }
276
277 static void add_people_count(struct strbuf *out, struct string_list *people)
278 {
279         if (people->nr == 1)
280                 strbuf_addstr(out, people->items[0].string);
281         else if (people->nr == 2)
282                 strbuf_addf(out, "%s (%d) and %s (%d)",
283                             people->items[0].string,
284                             (int)util_as_integral(&people->items[0]),
285                             people->items[1].string,
286                             (int)util_as_integral(&people->items[1]));
287         else if (people->nr)
288                 strbuf_addf(out, "%s (%d) and others",
289                             people->items[0].string,
290                             (int)util_as_integral(&people->items[0]));
291 }
292
293 static void credit_people(struct strbuf *out,
294                           struct string_list *them,
295                           int kind)
296 {
297         const char *label;
298         const char *me;
299
300         if (kind == 'a') {
301                 label = "By";
302                 me = git_author_info(IDENT_NO_DATE);
303         } else {
304                 label = "Via";
305                 me = git_committer_info(IDENT_NO_DATE);
306         }
307
308         if (!them->nr ||
309             (them->nr == 1 &&
310              me &&
311              skip_prefix(me, them->items->string, &me) &&
312              starts_with(me, " <")))
313                 return;
314         strbuf_addf(out, "\n%c %s ", comment_line_char, label);
315         add_people_count(out, them);
316 }
317
318 static void add_people_info(struct strbuf *out,
319                             struct string_list *authors,
320                             struct string_list *committers)
321 {
322         QSORT(authors->items, authors->nr,
323               cmp_string_list_util_as_integral);
324         QSORT(committers->items, committers->nr,
325               cmp_string_list_util_as_integral);
326
327         credit_people(out, authors, 'a');
328         credit_people(out, committers, 'c');
329 }
330
331 static void shortlog(const char *name,
332                      struct origin_data *origin_data,
333                      struct commit *head,
334                      struct rev_info *rev,
335                      struct fmt_merge_msg_opts *opts,
336                      struct strbuf *out)
337 {
338         int i, count = 0;
339         struct commit *commit;
340         struct object *branch;
341         struct string_list subjects = STRING_LIST_INIT_DUP;
342         struct string_list authors = STRING_LIST_INIT_DUP;
343         struct string_list committers = STRING_LIST_INIT_DUP;
344         int flags = UNINTERESTING | TREESAME | SEEN | SHOWN | ADDED;
345         struct strbuf sb = STRBUF_INIT;
346         const struct object_id *oid = &origin_data->oid;
347         int limit = opts->shortlog_len;
348
349         branch = deref_tag(the_repository, parse_object(the_repository, oid),
350                            oid_to_hex(oid),
351                            the_hash_algo->hexsz);
352         if (!branch || branch->type != OBJ_COMMIT)
353                 return;
354
355         setup_revisions(0, NULL, rev, NULL);
356         add_pending_object(rev, branch, name);
357         add_pending_object(rev, &head->object, "^HEAD");
358         head->object.flags |= UNINTERESTING;
359         if (prepare_revision_walk(rev))
360                 die("revision walk setup failed");
361         while ((commit = get_revision(rev)) != NULL) {
362                 struct pretty_print_context ctx = {0};
363
364                 if (commit->parents && commit->parents->next) {
365                         /* do not list a merge but count committer */
366                         if (opts->credit_people)
367                                 record_person('c', &committers, commit);
368                         continue;
369                 }
370                 if (!count && opts->credit_people)
371                         /* the 'tip' committer */
372                         record_person('c', &committers, commit);
373                 if (opts->credit_people)
374                         record_person('a', &authors, commit);
375                 count++;
376                 if (subjects.nr > limit)
377                         continue;
378
379                 format_commit_message(commit, "%s", &sb, &ctx);
380                 strbuf_ltrim(&sb);
381
382                 if (!sb.len)
383                         string_list_append(&subjects,
384                                            oid_to_hex(&commit->object.oid));
385                 else
386                         string_list_append_nodup(&subjects,
387                                                  strbuf_detach(&sb, NULL));
388         }
389
390         if (opts->credit_people)
391                 add_people_info(out, &authors, &committers);
392         if (count > limit)
393                 strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
394         else
395                 strbuf_addf(out, "\n* %s:\n", name);
396
397         if (origin_data->is_local_branch && use_branch_desc)
398                 add_branch_desc(out, name);
399
400         for (i = 0; i < subjects.nr; i++)
401                 if (i >= limit)
402                         strbuf_addstr(out, "  ...\n");
403                 else
404                         strbuf_addf(out, "  %s\n", subjects.items[i].string);
405
406         clear_commit_marks((struct commit *)branch, flags);
407         clear_commit_marks(head, flags);
408         free_commit_list(rev->commits);
409         rev->commits = NULL;
410         rev->pending.nr = 0;
411
412         string_list_clear(&authors, 0);
413         string_list_clear(&committers, 0);
414         string_list_clear(&subjects, 0);
415 }
416
417 static void fmt_merge_msg_title(struct strbuf *out,
418                                 const char *current_branch)
419 {
420         int i = 0;
421         char *sep = "";
422
423         strbuf_addstr(out, "Merge ");
424         for (i = 0; i < srcs.nr; i++) {
425                 struct src_data *src_data = srcs.items[i].util;
426                 const char *subsep = "";
427
428                 strbuf_addstr(out, sep);
429                 sep = "; ";
430
431                 if (src_data->head_status == 1) {
432                         strbuf_addstr(out, srcs.items[i].string);
433                         continue;
434                 }
435                 if (src_data->head_status == 3) {
436                         subsep = ", ";
437                         strbuf_addstr(out, "HEAD");
438                 }
439                 if (src_data->branch.nr) {
440                         strbuf_addstr(out, subsep);
441                         subsep = ", ";
442                         print_joined("branch ", "branches ", &src_data->branch,
443                                         out);
444                 }
445                 if (src_data->r_branch.nr) {
446                         strbuf_addstr(out, subsep);
447                         subsep = ", ";
448                         print_joined("remote-tracking branch ", "remote-tracking branches ",
449                                         &src_data->r_branch, out);
450                 }
451                 if (src_data->tag.nr) {
452                         strbuf_addstr(out, subsep);
453                         subsep = ", ";
454                         print_joined("tag ", "tags ", &src_data->tag, out);
455                 }
456                 if (src_data->generic.nr) {
457                         strbuf_addstr(out, subsep);
458                         print_joined("commit ", "commits ", &src_data->generic,
459                                         out);
460                 }
461                 if (strcmp(".", srcs.items[i].string))
462                         strbuf_addf(out, " of %s", srcs.items[i].string);
463         }
464
465         if (!strcmp("master", current_branch))
466                 strbuf_addch(out, '\n');
467         else
468                 strbuf_addf(out, " into %s\n", current_branch);
469 }
470
471 static void fmt_tag_signature(struct strbuf *tagbuf,
472                               struct strbuf *sig,
473                               const char *buf,
474                               unsigned long len)
475 {
476         const char *tag_body = strstr(buf, "\n\n");
477         if (tag_body) {
478                 tag_body += 2;
479                 strbuf_add(tagbuf, tag_body, buf + len - tag_body);
480         }
481         strbuf_complete_line(tagbuf);
482         if (sig->len) {
483                 strbuf_addch(tagbuf, '\n');
484                 strbuf_add_commented_lines(tagbuf, sig->buf, sig->len);
485         }
486 }
487
488 static void fmt_merge_msg_sigs(struct strbuf *out)
489 {
490         int i, tag_number = 0, first_tag = 0;
491         struct strbuf tagbuf = STRBUF_INIT;
492
493         for (i = 0; i < origins.nr; i++) {
494                 struct object_id *oid = origins.items[i].util;
495                 enum object_type type;
496                 unsigned long size, len;
497                 char *buf = read_object_file(oid, &type, &size);
498                 struct strbuf sig = STRBUF_INIT;
499
500                 if (!buf || type != OBJ_TAG)
501                         goto next;
502                 len = parse_signature(buf, size);
503
504                 if (size == len)
505                         ; /* merely annotated */
506                 else if (verify_signed_buffer(buf, len, buf + len, size - len, &sig, NULL)) {
507                         if (!sig.len)
508                                 strbuf_addstr(&sig, "gpg verification failed.\n");
509                 }
510
511                 if (!tag_number++) {
512                         fmt_tag_signature(&tagbuf, &sig, buf, len);
513                         first_tag = i;
514                 } else {
515                         if (tag_number == 2) {
516                                 struct strbuf tagline = STRBUF_INIT;
517                                 strbuf_addch(&tagline, '\n');
518                                 strbuf_add_commented_lines(&tagline,
519                                                 origins.items[first_tag].string,
520                                                 strlen(origins.items[first_tag].string));
521                                 strbuf_insert(&tagbuf, 0, tagline.buf,
522                                               tagline.len);
523                                 strbuf_release(&tagline);
524                         }
525                         strbuf_addch(&tagbuf, '\n');
526                         strbuf_add_commented_lines(&tagbuf,
527                                         origins.items[i].string,
528                                         strlen(origins.items[i].string));
529                         fmt_tag_signature(&tagbuf, &sig, buf, len);
530                 }
531                 strbuf_release(&sig);
532         next:
533                 free(buf);
534         }
535         if (tagbuf.len) {
536                 strbuf_addch(out, '\n');
537                 strbuf_addbuf(out, &tagbuf);
538         }
539         strbuf_release(&tagbuf);
540 }
541
542 static void find_merge_parents(struct merge_parents *result,
543                                struct strbuf *in, struct object_id *head)
544 {
545         struct commit_list *parents;
546         struct commit *head_commit;
547         int pos = 0, i, j;
548
549         parents = NULL;
550         while (pos < in->len) {
551                 int len;
552                 char *p = in->buf + pos;
553                 char *newline = strchr(p, '\n');
554                 const char *q;
555                 struct object_id oid;
556                 struct commit *parent;
557                 struct object *obj;
558
559                 len = newline ? newline - p : strlen(p);
560                 pos += len + !!newline;
561
562                 if (parse_oid_hex(p, &oid, &q) ||
563                     q[0] != '\t' ||
564                     q[1] != '\t')
565                         continue; /* skip not-for-merge */
566                 /*
567                  * Do not use get_merge_parent() here; we do not have
568                  * "name" here and we do not want to contaminate its
569                  * util field yet.
570                  */
571                 obj = parse_object(the_repository, &oid);
572                 parent = (struct commit *)peel_to_type(NULL, 0, obj, OBJ_COMMIT);
573                 if (!parent)
574                         continue;
575                 commit_list_insert(parent, &parents);
576                 add_merge_parent(result, &obj->oid, &parent->object.oid);
577         }
578         head_commit = lookup_commit(the_repository, head);
579         if (head_commit)
580                 commit_list_insert(head_commit, &parents);
581         reduce_heads_replace(&parents);
582
583         while (parents) {
584                 struct commit *cmit = pop_commit(&parents);
585                 for (i = 0; i < result->nr; i++)
586                         if (oideq(&result->item[i].commit, &cmit->object.oid))
587                                 result->item[i].used = 1;
588         }
589
590         for (i = j = 0; i < result->nr; i++) {
591                 if (result->item[i].used) {
592                         if (i != j)
593                                 result->item[j] = result->item[i];
594                         j++;
595                 }
596         }
597         result->nr = j;
598 }
599
600 int fmt_merge_msg(struct strbuf *in, struct strbuf *out,
601                   struct fmt_merge_msg_opts *opts)
602 {
603         int i = 0, pos = 0;
604         struct object_id head_oid;
605         const char *current_branch;
606         void *current_branch_to_free;
607         struct merge_parents merge_parents;
608
609         memset(&merge_parents, 0, sizeof(merge_parents));
610
611         /* get current branch */
612         current_branch = current_branch_to_free =
613                 resolve_refdup("HEAD", RESOLVE_REF_READING, &head_oid, NULL);
614         if (!current_branch)
615                 die("No current branch");
616         if (starts_with(current_branch, "refs/heads/"))
617                 current_branch += 11;
618
619         find_merge_parents(&merge_parents, in, &head_oid);
620
621         /* get a line */
622         while (pos < in->len) {
623                 int len;
624                 char *newline, *p = in->buf + pos;
625
626                 newline = strchr(p, '\n');
627                 len = newline ? newline - p : strlen(p);
628                 pos += len + !!newline;
629                 i++;
630                 p[len] = 0;
631                 if (handle_line(p, &merge_parents))
632                         die("error in line %d: %.*s", i, len, p);
633         }
634
635         if (opts->add_title && srcs.nr)
636                 fmt_merge_msg_title(out, current_branch);
637
638         if (origins.nr)
639                 fmt_merge_msg_sigs(out);
640
641         if (opts->shortlog_len) {
642                 struct commit *head;
643                 struct rev_info rev;
644
645                 head = lookup_commit_or_die(&head_oid, "HEAD");
646                 repo_init_revisions(the_repository, &rev, NULL);
647                 rev.commit_format = CMIT_FMT_ONELINE;
648                 rev.ignore_merges = 1;
649                 rev.limited = 1;
650
651                 strbuf_complete_line(out);
652
653                 for (i = 0; i < origins.nr; i++)
654                         shortlog(origins.items[i].string,
655                                  origins.items[i].util,
656                                  head, &rev, opts, out);
657         }
658
659         strbuf_complete_line(out);
660         free(current_branch_to_free);
661         free(merge_parents.item);
662         return 0;
663 }
664
665 int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
666 {
667         const char *inpath = NULL;
668         const char *message = NULL;
669         int shortlog_len = -1;
670         struct option options[] = {
671                 { OPTION_INTEGER, 0, "log", &shortlog_len, N_("n"),
672                   N_("populate log with at most <n> entries from shortlog"),
673                   PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
674                 { OPTION_INTEGER, 0, "summary", &shortlog_len, N_("n"),
675                   N_("alias for --log (deprecated)"),
676                   PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, NULL,
677                   DEFAULT_MERGE_LOG_LEN },
678                 OPT_STRING('m', "message", &message, N_("text"),
679                         N_("use <text> as start of message")),
680                 OPT_FILENAME('F', "file", &inpath, N_("file to read from")),
681                 OPT_END()
682         };
683
684         FILE *in = stdin;
685         struct strbuf input = STRBUF_INIT, output = STRBUF_INIT;
686         int ret;
687         struct fmt_merge_msg_opts opts;
688
689         git_config(fmt_merge_msg_config, NULL);
690         argc = parse_options(argc, argv, prefix, options, fmt_merge_msg_usage,
691                              0);
692         if (argc > 0)
693                 usage_with_options(fmt_merge_msg_usage, options);
694         if (shortlog_len < 0)
695                 shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
696
697         if (inpath && strcmp(inpath, "-")) {
698                 in = fopen(inpath, "r");
699                 if (!in)
700                         die_errno("cannot open '%s'", inpath);
701         }
702
703         if (strbuf_read(&input, fileno(in), 0) < 0)
704                 die_errno("could not read input file");
705
706         if (message)
707                 strbuf_addstr(&output, message);
708
709         memset(&opts, 0, sizeof(opts));
710         opts.add_title = !message;
711         opts.credit_people = 1;
712         opts.shortlog_len = shortlog_len;
713
714         ret = fmt_merge_msg(&input, &output, &opts);
715         if (ret)
716                 return ret;
717         write_in_full(STDOUT_FILENO, output.buf, output.len);
718         return 0;
719 }