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