Merge branch 'tf/prompt-preserve-exit-status'
[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;
104         const char *origin;
105         struct src_data *src_data;
106         struct string_list_item *item;
107         int pulling_head = 0;
108         unsigned char sha1[20];
109
110         if (len < 43 || line[40] != '\t')
111                 return 1;
112
113         if (starts_with(line + 41, "not-for-merge"))
114                 return 0;
115
116         if (line[41] != '\t')
117                 return 2;
118
119         i = get_sha1_hex(line, sha1);
120         if (i)
121                 return 3;
122
123         if (!find_merge_parent(merge_parents, sha1, NULL))
124                 return 0; /* subsumed by other parents */
125
126         origin_data = xcalloc(1, sizeof(struct origin_data));
127         hashcpy(origin_data->sha1, sha1);
128
129         if (line[len - 1] == '\n')
130                 line[len - 1] = 0;
131         line += 42;
132
133         /*
134          * At this point, line points at the beginning of comment e.g.
135          * "branch 'frotz' of git://that/repository.git".
136          * Find the repository name and point it with src.
137          */
138         src = strstr(line, " of ");
139         if (src) {
140                 *src = 0;
141                 src += 4;
142                 pulling_head = 0;
143         } else {
144                 src = line;
145                 pulling_head = 1;
146         }
147
148         item = unsorted_string_list_lookup(&srcs, src);
149         if (!item) {
150                 item = string_list_append(&srcs, src);
151                 item->util = xcalloc(1, sizeof(struct src_data));
152                 init_src_data(item->util);
153         }
154         src_data = item->util;
155
156         if (pulling_head) {
157                 origin = src;
158                 src_data->head_status |= 1;
159         } else if (starts_with(line, "branch ")) {
160                 origin_data->is_local_branch = 1;
161                 origin = line + 7;
162                 string_list_append(&src_data->branch, origin);
163                 src_data->head_status |= 2;
164         } else if (starts_with(line, "tag ")) {
165                 origin = line;
166                 string_list_append(&src_data->tag, origin + 4);
167                 src_data->head_status |= 2;
168         } else if (skip_prefix(line, "remote-tracking branch ", &origin)) {
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                 origin = xstrfmt("%s of %s", origin, src);
183         if (strcmp(".", src))
184                 origin_data->is_local_branch = 0;
185         string_list_append(&origins, origin)->util = origin_data;
186         return 0;
187 }
188
189 static void print_joined(const char *singular, const char *plural,
190                 struct string_list *list, struct strbuf *out)
191 {
192         if (list->nr == 0)
193                 return;
194         if (list->nr == 1) {
195                 strbuf_addf(out, "%s%s", singular, list->items[0].string);
196         } else {
197                 int i;
198                 strbuf_addstr(out, plural);
199                 for (i = 0; i < list->nr - 1; i++)
200                         strbuf_addf(out, "%s%s", i > 0 ? ", " : "",
201                                     list->items[i].string);
202                 strbuf_addf(out, " and %s", list->items[list->nr - 1].string);
203         }
204 }
205
206 static void add_branch_desc(struct strbuf *out, const char *name)
207 {
208         struct strbuf desc = STRBUF_INIT;
209
210         if (!read_branch_desc(&desc, name)) {
211                 const char *bp = desc.buf;
212                 while (*bp) {
213                         const char *ep = strchrnul(bp, '\n');
214                         if (*ep)
215                                 ep++;
216                         strbuf_addf(out, "  : %.*s", (int)(ep - bp), bp);
217                         bp = ep;
218                 }
219                 strbuf_complete_line(out);
220         }
221         strbuf_release(&desc);
222 }
223
224 #define util_as_integral(elem) ((intptr_t)((elem)->util))
225
226 static void record_person(int which, struct string_list *people,
227                           struct commit *commit)
228 {
229         const char *buffer;
230         char *name_buf, *name, *name_end;
231         struct string_list_item *elem;
232         const char *field;
233
234         field = (which == 'a') ? "\nauthor " : "\ncommitter ";
235         buffer = get_commit_buffer(commit, NULL);
236         name = strstr(buffer, field);
237         if (!name)
238                 return;
239         name += strlen(field);
240         name_end = strchrnul(name, '<');
241         if (*name_end)
242                 name_end--;
243         while (isspace(*name_end) && name <= name_end)
244                 name_end--;
245         if (name_end < name)
246                 return;
247         name_buf = xmemdupz(name, name_end - name + 1);
248         unuse_commit_buffer(commit, buffer);
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 = "By";
290                 me = git_author_info(IDENT_NO_DATE);
291         } else {
292                 label = "Via";
293                 me = git_committer_info(IDENT_NO_DATE);
294         }
295
296         if (!them->nr ||
297             (them->nr == 1 &&
298              me &&
299              skip_prefix(me, them->items->string, &me) &&
300              starts_with(me, " <")))
301                 return;
302         strbuf_addf(out, "\n%c %s ", comment_line_char, 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,
327                      struct fmt_merge_msg_opts *opts,
328                      struct strbuf *out)
329 {
330         int i, count = 0;
331         struct commit *commit;
332         struct object *branch;
333         struct string_list subjects = STRING_LIST_INIT_DUP;
334         struct string_list authors = STRING_LIST_INIT_DUP;
335         struct string_list committers = STRING_LIST_INIT_DUP;
336         int flags = UNINTERESTING | TREESAME | SEEN | SHOWN | ADDED;
337         struct strbuf sb = STRBUF_INIT;
338         const unsigned char *sha1 = origin_data->sha1;
339         int limit = opts->shortlog_len;
340
341         branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
342         if (!branch || branch->type != OBJ_COMMIT)
343                 return;
344
345         setup_revisions(0, NULL, rev, NULL);
346         add_pending_object(rev, branch, name);
347         add_pending_object(rev, &head->object, "^HEAD");
348         head->object.flags |= UNINTERESTING;
349         if (prepare_revision_walk(rev))
350                 die("revision walk setup failed");
351         while ((commit = get_revision(rev)) != NULL) {
352                 struct pretty_print_context ctx = {0};
353
354                 if (commit->parents && commit->parents->next) {
355                         /* do not list a merge but count committer */
356                         if (opts->credit_people)
357                                 record_person('c', &committers, commit);
358                         continue;
359                 }
360                 if (!count && opts->credit_people)
361                         /* the 'tip' committer */
362                         record_person('c', &committers, commit);
363                 if (opts->credit_people)
364                         record_person('a', &authors, commit);
365                 count++;
366                 if (subjects.nr > limit)
367                         continue;
368
369                 format_commit_message(commit, "%s", &sb, &ctx);
370                 strbuf_ltrim(&sb);
371
372                 if (!sb.len)
373                         string_list_append(&subjects,
374                                            sha1_to_hex(commit->object.sha1));
375                 else
376                         string_list_append(&subjects, strbuf_detach(&sb, NULL));
377         }
378
379         if (opts->credit_people)
380                 add_people_info(out, &authors, &committers);
381         if (count > limit)
382                 strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
383         else
384                 strbuf_addf(out, "\n* %s:\n", name);
385
386         if (origin_data->is_local_branch && use_branch_desc)
387                 add_branch_desc(out, name);
388
389         for (i = 0; i < subjects.nr; i++)
390                 if (i >= limit)
391                         strbuf_addf(out, "  ...\n");
392                 else
393                         strbuf_addf(out, "  %s\n", subjects.items[i].string);
394
395         clear_commit_marks((struct commit *)branch, flags);
396         clear_commit_marks(head, flags);
397         free_commit_list(rev->commits);
398         rev->commits = NULL;
399         rev->pending.nr = 0;
400
401         string_list_clear(&authors, 0);
402         string_list_clear(&committers, 0);
403         string_list_clear(&subjects, 0);
404 }
405
406 static void fmt_merge_msg_title(struct strbuf *out,
407         const char *current_branch) {
408         int i = 0;
409         char *sep = "";
410
411         strbuf_addstr(out, "Merge ");
412         for (i = 0; i < srcs.nr; i++) {
413                 struct src_data *src_data = srcs.items[i].util;
414                 const char *subsep = "";
415
416                 strbuf_addstr(out, sep);
417                 sep = "; ";
418
419                 if (src_data->head_status == 1) {
420                         strbuf_addstr(out, srcs.items[i].string);
421                         continue;
422                 }
423                 if (src_data->head_status == 3) {
424                         subsep = ", ";
425                         strbuf_addstr(out, "HEAD");
426                 }
427                 if (src_data->branch.nr) {
428                         strbuf_addstr(out, subsep);
429                         subsep = ", ";
430                         print_joined("branch ", "branches ", &src_data->branch,
431                                         out);
432                 }
433                 if (src_data->r_branch.nr) {
434                         strbuf_addstr(out, subsep);
435                         subsep = ", ";
436                         print_joined("remote-tracking branch ", "remote-tracking branches ",
437                                         &src_data->r_branch, out);
438                 }
439                 if (src_data->tag.nr) {
440                         strbuf_addstr(out, subsep);
441                         subsep = ", ";
442                         print_joined("tag ", "tags ", &src_data->tag, out);
443                 }
444                 if (src_data->generic.nr) {
445                         strbuf_addstr(out, subsep);
446                         print_joined("commit ", "commits ", &src_data->generic,
447                                         out);
448                 }
449                 if (strcmp(".", srcs.items[i].string))
450                         strbuf_addf(out, " of %s", srcs.items[i].string);
451         }
452
453         if (!strcmp("master", current_branch))
454                 strbuf_addch(out, '\n');
455         else
456                 strbuf_addf(out, " into %s\n", current_branch);
457 }
458
459 static void fmt_tag_signature(struct strbuf *tagbuf,
460                               struct strbuf *sig,
461                               const char *buf,
462                               unsigned long len)
463 {
464         const char *tag_body = strstr(buf, "\n\n");
465         if (tag_body) {
466                 tag_body += 2;
467                 strbuf_add(tagbuf, tag_body, buf + len - tag_body);
468         }
469         strbuf_complete_line(tagbuf);
470         if (sig->len) {
471                 strbuf_addch(tagbuf, '\n');
472                 strbuf_add_commented_lines(tagbuf, sig->buf, sig->len);
473         }
474 }
475
476 static void fmt_merge_msg_sigs(struct strbuf *out)
477 {
478         int i, tag_number = 0, first_tag = 0;
479         struct strbuf tagbuf = STRBUF_INIT;
480
481         for (i = 0; i < origins.nr; i++) {
482                 unsigned char *sha1 = origins.items[i].util;
483                 enum object_type type;
484                 unsigned long size, len;
485                 char *buf = read_sha1_file(sha1, &type, &size);
486                 struct strbuf sig = STRBUF_INIT;
487
488                 if (!buf || type != OBJ_TAG)
489                         goto next;
490                 len = parse_signature(buf, size);
491
492                 if (size == len)
493                         ; /* merely annotated */
494                 else if (verify_signed_buffer(buf, len, buf + len, size - len, &sig, NULL)) {
495                         if (!sig.len)
496                                 strbuf_addstr(&sig, "gpg verification failed.\n");
497                 }
498
499                 if (!tag_number++) {
500                         fmt_tag_signature(&tagbuf, &sig, buf, len);
501                         first_tag = i;
502                 } else {
503                         if (tag_number == 2) {
504                                 struct strbuf tagline = STRBUF_INIT;
505                                 strbuf_addch(&tagline, '\n');
506                                 strbuf_add_commented_lines(&tagline,
507                                                 origins.items[first_tag].string,
508                                                 strlen(origins.items[first_tag].string));
509                                 strbuf_insert(&tagbuf, 0, tagline.buf,
510                                               tagline.len);
511                                 strbuf_release(&tagline);
512                         }
513                         strbuf_addch(&tagbuf, '\n');
514                         strbuf_add_commented_lines(&tagbuf,
515                                         origins.items[i].string,
516                                         strlen(origins.items[i].string));
517                         fmt_tag_signature(&tagbuf, &sig, buf, len);
518                 }
519                 strbuf_release(&sig);
520         next:
521                 free(buf);
522         }
523         if (tagbuf.len) {
524                 strbuf_addch(out, '\n');
525                 strbuf_addbuf(out, &tagbuf);
526         }
527         strbuf_release(&tagbuf);
528 }
529
530 static void find_merge_parents(struct merge_parents *result,
531                                struct strbuf *in, unsigned char *head)
532 {
533         struct commit_list *parents, *next;
534         struct commit *head_commit;
535         int pos = 0, i, j;
536
537         parents = NULL;
538         while (pos < in->len) {
539                 int len;
540                 char *p = in->buf + pos;
541                 char *newline = strchr(p, '\n');
542                 unsigned char sha1[20];
543                 struct commit *parent;
544                 struct object *obj;
545
546                 len = newline ? newline - p : strlen(p);
547                 pos += len + !!newline;
548
549                 if (len < 43 ||
550                     get_sha1_hex(p, sha1) ||
551                     p[40] != '\t' ||
552                     p[41] != '\t')
553                         continue; /* skip not-for-merge */
554                 /*
555                  * Do not use get_merge_parent() here; we do not have
556                  * "name" here and we do not want to contaminate its
557                  * util field yet.
558                  */
559                 obj = parse_object(sha1);
560                 parent = (struct commit *)peel_to_type(NULL, 0, obj, OBJ_COMMIT);
561                 if (!parent)
562                         continue;
563                 commit_list_insert(parent, &parents);
564                 add_merge_parent(result, obj->sha1, parent->object.sha1);
565         }
566         head_commit = lookup_commit(head);
567         if (head_commit)
568                 commit_list_insert(head_commit, &parents);
569         parents = reduce_heads(parents);
570
571         while (parents) {
572                 for (i = 0; i < result->nr; i++)
573                         if (!hashcmp(result->item[i].commit,
574                                      parents->item->object.sha1))
575                                 result->item[i].used = 1;
576                 next = parents->next;
577                 free(parents);
578                 parents = next;
579         }
580
581         for (i = j = 0; i < result->nr; i++) {
582                 if (result->item[i].used) {
583                         if (i != j)
584                                 result->item[j] = result->item[i];
585                         j++;
586                 }
587         }
588         result->nr = j;
589 }
590
591 int fmt_merge_msg(struct strbuf *in, struct strbuf *out,
592                   struct fmt_merge_msg_opts *opts)
593 {
594         int i = 0, pos = 0;
595         unsigned char head_sha1[20];
596         const char *current_branch;
597         void *current_branch_to_free;
598         struct merge_parents merge_parents;
599
600         memset(&merge_parents, 0, sizeof(merge_parents));
601
602         /* get current branch */
603         current_branch = current_branch_to_free =
604                 resolve_refdup("HEAD", RESOLVE_REF_READING, head_sha1, NULL);
605         if (!current_branch)
606                 die("No current branch");
607         if (starts_with(current_branch, "refs/heads/"))
608                 current_branch += 11;
609
610         find_merge_parents(&merge_parents, in, head_sha1);
611
612         /* get a line */
613         while (pos < in->len) {
614                 int len;
615                 char *newline, *p = in->buf + pos;
616
617                 newline = strchr(p, '\n');
618                 len = newline ? newline - p : strlen(p);
619                 pos += len + !!newline;
620                 i++;
621                 p[len] = 0;
622                 if (handle_line(p, &merge_parents))
623                         die ("Error in line %d: %.*s", i, len, p);
624         }
625
626         if (opts->add_title && srcs.nr)
627                 fmt_merge_msg_title(out, current_branch);
628
629         if (origins.nr)
630                 fmt_merge_msg_sigs(out);
631
632         if (opts->shortlog_len) {
633                 struct commit *head;
634                 struct rev_info rev;
635
636                 head = lookup_commit_or_die(head_sha1, "HEAD");
637                 init_revisions(&rev, NULL);
638                 rev.commit_format = CMIT_FMT_ONELINE;
639                 rev.ignore_merges = 1;
640                 rev.limited = 1;
641
642                 strbuf_complete_line(out);
643
644                 for (i = 0; i < origins.nr; i++)
645                         shortlog(origins.items[i].string,
646                                  origins.items[i].util,
647                                  head, &rev, opts, out);
648         }
649
650         strbuf_complete_line(out);
651         free(current_branch_to_free);
652         free(merge_parents.item);
653         return 0;
654 }
655
656 int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
657 {
658         const char *inpath = NULL;
659         const char *message = NULL;
660         int shortlog_len = -1;
661         struct option options[] = {
662                 { OPTION_INTEGER, 0, "log", &shortlog_len, N_("n"),
663                   N_("populate log with at most <n> entries from shortlog"),
664                   PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
665                 { OPTION_INTEGER, 0, "summary", &shortlog_len, N_("n"),
666                   N_("alias for --log (deprecated)"),
667                   PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, NULL,
668                   DEFAULT_MERGE_LOG_LEN },
669                 OPT_STRING('m', "message", &message, N_("text"),
670                         N_("use <text> as start of message")),
671                 OPT_FILENAME('F', "file", &inpath, N_("file to read from")),
672                 OPT_END()
673         };
674
675         FILE *in = stdin;
676         struct strbuf input = STRBUF_INIT, output = STRBUF_INIT;
677         int ret;
678         struct fmt_merge_msg_opts opts;
679
680         git_config(fmt_merge_msg_config, NULL);
681         argc = parse_options(argc, argv, prefix, options, fmt_merge_msg_usage,
682                              0);
683         if (argc > 0)
684                 usage_with_options(fmt_merge_msg_usage, options);
685         if (shortlog_len < 0)
686                 shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
687
688         if (inpath && strcmp(inpath, "-")) {
689                 in = fopen(inpath, "r");
690                 if (!in)
691                         die_errno("cannot open '%s'", inpath);
692         }
693
694         if (strbuf_read(&input, fileno(in), 0) < 0)
695                 die_errno("could not read input file");
696
697         if (message)
698                 strbuf_addstr(&output, message);
699
700         memset(&opts, 0, sizeof(opts));
701         opts.add_title = !message;
702         opts.credit_people = 1;
703         opts.shortlog_len = shortlog_len;
704
705         ret = fmt_merge_msg(&input, &output, &opts);
706         if (ret)
707                 return ret;
708         write_in_full(STDOUT_FILENO, output.buf, output.len);
709         return 0;
710 }