summaryrefslogtreecommitdiff
path: root/builtin/fmt-merge-msg.c
blob: 46c92c174fd06ba5e0b2a06dec13733842bb48f3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
#include "builtin.h"
#include "cache.h"
#include "commit.h"
#include "diff.h"
#include "revision.h"
#include "tag.h"
#include "string-list.h"
#include "branch.h"
#include "fmt-merge-msg.h"
#include "gpg-interface.h"

static const char * const fmt_merge_msg_usage[] = {
	N_("git fmt-merge-msg [-m <message>] [--log[=<n>] | --no-log] [--file <file>]"),
	NULL
};

static int use_branch_desc;

int fmt_merge_msg_config(const char *key, const char *value, void *cb)
{
	if (!strcmp(key, "merge.log") || !strcmp(key, "merge.summary")) {
		int is_bool;
		merge_log_config = git_config_bool_or_int(key, value, &is_bool);
		if (!is_bool && merge_log_config < 0)
			return error("%s: negative length %s", key, value);
		if (is_bool && merge_log_config)
			merge_log_config = DEFAULT_MERGE_LOG_LEN;
	} else if (!strcmp(key, "merge.branchdesc")) {
		use_branch_desc = git_config_bool(key, value);
	} else {
		return git_default_config(key, value, cb);
	}
	return 0;
}

/* merge data per repository where the merged tips came from */
struct src_data {
	struct string_list branch, tag, r_branch, generic;
	int head_status;
};

struct origin_data {
	unsigned char sha1[20];
	unsigned is_local_branch:1;
};

static void init_src_data(struct src_data *data)
{
	data->branch.strdup_strings = 1;
	data->tag.strdup_strings = 1;
	data->r_branch.strdup_strings = 1;
	data->generic.strdup_strings = 1;
}

static struct string_list srcs = STRING_LIST_INIT_DUP;
static struct string_list origins = STRING_LIST_INIT_DUP;

struct merge_parents {
	int alloc, nr;
	struct merge_parent {
		unsigned char given[20];
		unsigned char commit[20];
		unsigned char used;
	} *item;
};

/*
 * I know, I know, this is inefficient, but you won't be pulling and merging
 * hundreds of heads at a time anyway.
 */
static struct merge_parent *find_merge_parent(struct merge_parents *table,
					      unsigned char *given,
					      unsigned char *commit)
{
	int i;
	for (i = 0; i < table->nr; i++) {
		if (given && hashcmp(table->item[i].given, given))
			continue;
		if (commit && hashcmp(table->item[i].commit, commit))
			continue;
		return &table->item[i];
	}
	return NULL;
}

static void add_merge_parent(struct merge_parents *table,
			     unsigned char *given,
			     unsigned char *commit)
{
	if (table->nr && find_merge_parent(table, given, commit))
		return;
	ALLOC_GROW(table->item, table->nr + 1, table->alloc);
	hashcpy(table->item[table->nr].given, given);
	hashcpy(table->item[table->nr].commit, commit);
	table->item[table->nr].used = 0;
	table->nr++;
}

static int handle_line(char *line, struct merge_parents *merge_parents)
{
	int i, len = strlen(line);
	struct origin_data *origin_data;
	char *src;
	const char *origin;
	struct src_data *src_data;
	struct string_list_item *item;
	int pulling_head = 0;
	unsigned char sha1[20];

	if (len < 43 || line[40] != '\t')
		return 1;

	if (starts_with(line + 41, "not-for-merge"))
		return 0;

	if (line[41] != '\t')
		return 2;

	i = get_sha1_hex(line, sha1);
	if (i)
		return 3;

	if (!find_merge_parent(merge_parents, sha1, NULL))
		return 0; /* subsumed by other parents */

	origin_data = xcalloc(1, sizeof(struct origin_data));
	hashcpy(origin_data->sha1, sha1);

	if (line[len - 1] == '\n')
		line[len - 1] = 0;
	line += 42;

	/*
	 * At this point, line points at the beginning of comment e.g.
	 * "branch 'frotz' of git://that/repository.git".
	 * Find the repository name and point it with src.
	 */
	src = strstr(line, " of ");
	if (src) {
		*src = 0;
		src += 4;
		pulling_head = 0;
	} else {
		src = line;
		pulling_head = 1;
	}

	item = unsorted_string_list_lookup(&srcs, src);
	if (!item) {
		item = string_list_append(&srcs, src);
		item->util = xcalloc(1, sizeof(struct src_data));
		init_src_data(item->util);
	}
	src_data = item->util;

	if (pulling_head) {
		origin = src;
		src_data->head_status |= 1;
	} else if (starts_with(line, "branch ")) {
		origin_data->is_local_branch = 1;
		origin = line + 7;
		string_list_append(&src_data->branch, origin);
		src_data->head_status |= 2;
	} else if (starts_with(line, "tag ")) {
		origin = line;
		string_list_append(&src_data->tag, origin + 4);
		src_data->head_status |= 2;
	} else if (skip_prefix(line, "remote-tracking branch ", &origin)) {
		string_list_append(&src_data->r_branch, origin);
		src_data->head_status |= 2;
	} else {
		origin = src;
		string_list_append(&src_data->generic, line);
		src_data->head_status |= 2;
	}

	if (!strcmp(".", src) || !strcmp(src, origin)) {
		int len = strlen(origin);
		if (origin[0] == '\'' && origin[len - 1] == '\'')
			origin = xmemdupz(origin + 1, len - 2);
	} else
		origin = xstrfmt("%s of %s", origin, src);
	if (strcmp(".", src))
		origin_data->is_local_branch = 0;
	string_list_append(&origins, origin)->util = origin_data;
	return 0;
}

static void print_joined(const char *singular, const char *plural,
		struct string_list *list, struct strbuf *out)
{
	if (list->nr == 0)
		return;
	if (list->nr == 1) {
		strbuf_addf(out, "%s%s", singular, list->items[0].string);
	} else {
		int i;
		strbuf_addstr(out, plural);
		for (i = 0; i < list->nr - 1; i++)
			strbuf_addf(out, "%s%s", i > 0 ? ", " : "",
				    list->items[i].string);
		strbuf_addf(out, " and %s", list->items[list->nr - 1].string);
	}
}

static void add_branch_desc(struct strbuf *out, const char *name)
{
	struct strbuf desc = STRBUF_INIT;

	if (!read_branch_desc(&desc, name)) {
		const char *bp = desc.buf;
		while (*bp) {
			const char *ep = strchrnul(bp, '\n');
			if (*ep)
				ep++;
			strbuf_addf(out, "  : %.*s", (int)(ep - bp), bp);
			bp = ep;
		}
		strbuf_complete_line(out);
	}
	strbuf_release(&desc);
}

#define util_as_integral(elem) ((intptr_t)((elem)->util))

static void record_person_from_buf(int which, struct string_list *people,
				   const char *buffer)
{
	char *name_buf, *name, *name_end;
	struct string_list_item *elem;
	const char *field;

	field = (which == 'a') ? "\nauthor " : "\ncommitter ";
	name = strstr(buffer, field);
	if (!name)
		return;
	name += strlen(field);
	name_end = strchrnul(name, '<');
	if (*name_end)
		name_end--;
	while (isspace(*name_end) && name <= name_end)
		name_end--;
	if (name_end < name)
		return;
	name_buf = xmemdupz(name, name_end - name + 1);

	elem = string_list_lookup(people, name_buf);
	if (!elem) {
		elem = string_list_insert(people, name_buf);
		elem->util = (void *)0;
	}
	elem->util = (void*)(util_as_integral(elem) + 1);
	free(name_buf);
}


static void record_person(int which, struct string_list *people,
			  struct commit *commit)
{
	const char *buffer = get_commit_buffer(commit, NULL);
	record_person_from_buf(which, people, buffer);
	unuse_commit_buffer(commit, buffer);
}

static int cmp_string_list_util_as_integral(const void *a_, const void *b_)
{
	const struct string_list_item *a = a_, *b = b_;
	return util_as_integral(b) - util_as_integral(a);
}

static void add_people_count(struct strbuf *out, struct string_list *people)
{
	if (people->nr == 1)
		strbuf_addf(out, "%s", people->items[0].string);
	else if (people->nr == 2)
		strbuf_addf(out, "%s (%d) and %s (%d)",
			    people->items[0].string,
			    (int)util_as_integral(&people->items[0]),
			    people->items[1].string,
			    (int)util_as_integral(&people->items[1]));
	else if (people->nr)
		strbuf_addf(out, "%s (%d) and others",
			    people->items[0].string,
			    (int)util_as_integral(&people->items[0]));
}

static void credit_people(struct strbuf *out,
			  struct string_list *them,
			  int kind)
{
	const char *label;
	const char *me;

	if (kind == 'a') {
		label = "By";
		me = git_author_info(IDENT_NO_DATE);
	} else {
		label = "Via";
		me = git_committer_info(IDENT_NO_DATE);
	}

	if (!them->nr ||
	    (them->nr == 1 &&
	     me &&
	     skip_prefix(me, them->items->string, &me) &&
	     starts_with(me, " <")))
		return;
	strbuf_addf(out, "\n%c %s ", comment_line_char, label);
	add_people_count(out, them);
}

static void add_people_info(struct strbuf *out,
			    struct string_list *authors,
			    struct string_list *committers)
{
	if (authors->nr)
		qsort(authors->items,
		      authors->nr, sizeof(authors->items[0]),
		      cmp_string_list_util_as_integral);
	if (committers->nr)
		qsort(committers->items,
		      committers->nr, sizeof(committers->items[0]),
		      cmp_string_list_util_as_integral);

	credit_people(out, authors, 'a');
	credit_people(out, committers, 'c');
}

static void shortlog(const char *name,
		     struct origin_data *origin_data,
		     struct commit *head,
		     struct rev_info *rev,
		     struct fmt_merge_msg_opts *opts,
		     struct strbuf *out)
{
	int i, count = 0;
	struct commit *commit;
	struct object *branch;
	struct string_list subjects = STRING_LIST_INIT_DUP;
	struct string_list authors = STRING_LIST_INIT_DUP;
	struct string_list committers = STRING_LIST_INIT_DUP;
	int flags = UNINTERESTING | TREESAME | SEEN | SHOWN | ADDED;
	struct strbuf sb = STRBUF_INIT;
	const unsigned char *sha1 = origin_data->sha1;
	int limit = opts->shortlog_len;

	branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
	if (!branch || branch->type != OBJ_COMMIT)
		return;

	setup_revisions(0, NULL, rev, NULL);
	add_pending_object(rev, branch, name);
	add_pending_object(rev, &head->object, "^HEAD");
	head->object.flags |= UNINTERESTING;
	if (prepare_revision_walk(rev))
		die("revision walk setup failed");
	while ((commit = get_revision(rev)) != NULL) {
		struct pretty_print_context ctx = {0};

		if (commit->parents && commit->parents->next) {
			/* do not list a merge but count committer */
			if (opts->credit_people)
				record_person('c', &committers, commit);
			continue;
		}
		if (!count && opts->credit_people)
			/* the 'tip' committer */
			record_person('c', &committers, commit);
		if (opts->credit_people)
			record_person('a', &authors, commit);
		count++;
		if (subjects.nr > limit)
			continue;

		format_commit_message(commit, "%s", &sb, &ctx);
		strbuf_ltrim(&sb);

		if (!sb.len)
			string_list_append(&subjects,
					   sha1_to_hex(commit->object.sha1));
		else
			string_list_append(&subjects, strbuf_detach(&sb, NULL));
	}

	if (opts->credit_people)
		add_people_info(out, &authors, &committers);
	if (count > limit)
		strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
	else
		strbuf_addf(out, "\n* %s:\n", name);

	if (origin_data->is_local_branch && use_branch_desc)
		add_branch_desc(out, name);

	for (i = 0; i < subjects.nr; i++)
		if (i >= limit)
			strbuf_addf(out, "  ...\n");
		else
			strbuf_addf(out, "  %s\n", subjects.items[i].string);

	clear_commit_marks((struct commit *)branch, flags);
	clear_commit_marks(head, flags);
	free_commit_list(rev->commits);
	rev->commits = NULL;
	rev->pending.nr = 0;

	string_list_clear(&authors, 0);
	string_list_clear(&committers, 0);
	string_list_clear(&subjects, 0);
}

static void fmt_merge_msg_title(struct strbuf *out,
	const char *current_branch) {
	int i = 0;
	char *sep = "";

	strbuf_addstr(out, "Merge ");
	for (i = 0; i < srcs.nr; i++) {
		struct src_data *src_data = srcs.items[i].util;
		const char *subsep = "";

		strbuf_addstr(out, sep);
		sep = "; ";

		if (src_data->head_status == 1) {
			strbuf_addstr(out, srcs.items[i].string);
			continue;
		}
		if (src_data->head_status == 3) {
			subsep = ", ";
			strbuf_addstr(out, "HEAD");
		}
		if (src_data->branch.nr) {
			strbuf_addstr(out, subsep);
			subsep = ", ";
			print_joined("branch ", "branches ", &src_data->branch,
					out);
		}
		if (src_data->r_branch.nr) {
			strbuf_addstr(out, subsep);
			subsep = ", ";
			print_joined("remote-tracking branch ", "remote-tracking branches ",
					&src_data->r_branch, out);
		}
		if (src_data->tag.nr) {
			strbuf_addstr(out, subsep);
			subsep = ", ";
			print_joined("tag ", "tags ", &src_data->tag, out);
		}
		if (src_data->generic.nr) {
			strbuf_addstr(out, subsep);
			print_joined("commit ", "commits ", &src_data->generic,
					out);
		}
		if (strcmp(".", srcs.items[i].string))
			strbuf_addf(out, " of %s", srcs.items[i].string);
	}

	if (!strcmp("master", current_branch))
		strbuf_addch(out, '\n');
	else
		strbuf_addf(out, " into %s\n", current_branch);
}

static void fmt_tag_signature(struct strbuf *tagbuf,
			      struct strbuf *sig,
			      const char *buf,
			      unsigned long len)
{
	const char *tag_body = strstr(buf, "\n\n");
	if (tag_body) {
		tag_body += 2;
		strbuf_add(tagbuf, tag_body, buf + len - tag_body);
	}
	strbuf_complete_line(tagbuf);
	if (sig->len) {
		strbuf_addch(tagbuf, '\n');
		strbuf_add_commented_lines(tagbuf, sig->buf, sig->len);
	}
}

static void fmt_merge_msg_sigs(struct strbuf *out)
{
	int i, tag_number = 0, first_tag = 0;
	struct strbuf tagbuf = STRBUF_INIT;

	for (i = 0; i < origins.nr; i++) {
		unsigned char *sha1 = origins.items[i].util;
		enum object_type type;
		unsigned long size, len;
		char *buf = read_sha1_file(sha1, &type, &size);
		struct strbuf sig = STRBUF_INIT;

		if (!buf || type != OBJ_TAG)
			goto next;
		len = parse_signature(buf, size);

		if (size == len)
			; /* merely annotated */
		else if (verify_signed_buffer(buf, len, buf + len, size - len, &sig, NULL)) {
			if (!sig.len)
				strbuf_addstr(&sig, "gpg verification failed.\n");
		}

		if (!tag_number++) {
			fmt_tag_signature(&tagbuf, &sig, buf, len);
			first_tag = i;
		} else {
			if (tag_number == 2) {
				struct strbuf tagline = STRBUF_INIT;
				strbuf_addch(&tagline, '\n');
				strbuf_add_commented_lines(&tagline,
						origins.items[first_tag].string,
						strlen(origins.items[first_tag].string));
				strbuf_insert(&tagbuf, 0, tagline.buf,
					      tagline.len);
				strbuf_release(&tagline);
			}
			strbuf_addch(&tagbuf, '\n');
			strbuf_add_commented_lines(&tagbuf,
					origins.items[i].string,
					strlen(origins.items[i].string));
			fmt_tag_signature(&tagbuf, &sig, buf, len);
		}
		strbuf_release(&sig);
	next:
		free(buf);
	}
	if (tagbuf.len) {
		strbuf_addch(out, '\n');
		strbuf_addbuf(out, &tagbuf);
	}
	strbuf_release(&tagbuf);
}

static void find_merge_parents(struct merge_parents *result,
			       struct strbuf *in, unsigned char *head)
{
	struct commit_list *parents;
	struct commit *head_commit;
	int pos = 0, i, j;

	parents = NULL;
	while (pos < in->len) {
		int len;
		char *p = in->buf + pos;
		char *newline = strchr(p, '\n');
		unsigned char sha1[20];
		struct commit *parent;
		struct object *obj;

		len = newline ? newline - p : strlen(p);
		pos += len + !!newline;

		if (len < 43 ||
		    get_sha1_hex(p, sha1) ||
		    p[40] != '\t' ||
		    p[41] != '\t')
			continue; /* skip not-for-merge */
		/*
		 * Do not use get_merge_parent() here; we do not have
		 * "name" here and we do not want to contaminate its
		 * util field yet.
		 */
		obj = parse_object(sha1);
		parent = (struct commit *)peel_to_type(NULL, 0, obj, OBJ_COMMIT);
		if (!parent)
			continue;
		commit_list_insert(parent, &parents);
		add_merge_parent(result, obj->sha1, parent->object.sha1);
	}
	head_commit = lookup_commit(head);
	if (head_commit)
		commit_list_insert(head_commit, &parents);
	parents = reduce_heads(parents);

	while (parents) {
		struct commit *cmit = pop_commit(&parents);
		for (i = 0; i < result->nr; i++)
			if (!hashcmp(result->item[i].commit, cmit->object.sha1))
				result->item[i].used = 1;
	}

	for (i = j = 0; i < result->nr; i++) {
		if (result->item[i].used) {
			if (i != j)
				result->item[j] = result->item[i];
			j++;
		}
	}
	result->nr = j;
}

int fmt_merge_msg(struct strbuf *in, struct strbuf *out,
		  struct fmt_merge_msg_opts *opts)
{
	int i = 0, pos = 0;
	unsigned char head_sha1[20];
	const char *current_branch;
	void *current_branch_to_free;
	struct merge_parents merge_parents;

	memset(&merge_parents, 0, sizeof(merge_parents));

	/* get current branch */
	current_branch = current_branch_to_free =
		resolve_refdup("HEAD", RESOLVE_REF_READING, head_sha1, NULL);
	if (!current_branch)
		die("No current branch");
	if (starts_with(current_branch, "refs/heads/"))
		current_branch += 11;

	find_merge_parents(&merge_parents, in, head_sha1);

	/* get a line */
	while (pos < in->len) {
		int len;
		char *newline, *p = in->buf + pos;

		newline = strchr(p, '\n');
		len = newline ? newline - p : strlen(p);
		pos += len + !!newline;
		i++;
		p[len] = 0;
		if (handle_line(p, &merge_parents))
			die ("Error in line %d: %.*s", i, len, p);
	}

	if (opts->add_title && srcs.nr)
		fmt_merge_msg_title(out, current_branch);

	if (origins.nr)
		fmt_merge_msg_sigs(out);

	if (opts->shortlog_len) {
		struct commit *head;
		struct rev_info rev;

		head = lookup_commit_or_die(head_sha1, "HEAD");
		init_revisions(&rev, NULL);
		rev.commit_format = CMIT_FMT_ONELINE;
		rev.ignore_merges = 1;
		rev.limited = 1;

		strbuf_complete_line(out);

		for (i = 0; i < origins.nr; i++)
			shortlog(origins.items[i].string,
				 origins.items[i].util,
				 head, &rev, opts, out);
	}

	strbuf_complete_line(out);
	free(current_branch_to_free);
	free(merge_parents.item);
	return 0;
}

int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
{
	const char *inpath = NULL;
	const char *message = NULL;
	int shortlog_len = -1;
	struct option options[] = {
		{ OPTION_INTEGER, 0, "log", &shortlog_len, N_("n"),
		  N_("populate log with at most <n> entries from shortlog"),
		  PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
		{ OPTION_INTEGER, 0, "summary", &shortlog_len, N_("n"),
		  N_("alias for --log (deprecated)"),
		  PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, NULL,
		  DEFAULT_MERGE_LOG_LEN },
		OPT_STRING('m', "message", &message, N_("text"),
			N_("use <text> as start of message")),
		OPT_FILENAME('F', "file", &inpath, N_("file to read from")),
		OPT_END()
	};

	FILE *in = stdin;
	struct strbuf input = STRBUF_INIT, output = STRBUF_INIT;
	int ret;
	struct fmt_merge_msg_opts opts;

	git_config(fmt_merge_msg_config, NULL);
	argc = parse_options(argc, argv, prefix, options, fmt_merge_msg_usage,
			     0);
	if (argc > 0)
		usage_with_options(fmt_merge_msg_usage, options);
	if (shortlog_len < 0)
		shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;

	if (inpath && strcmp(inpath, "-")) {
		in = fopen(inpath, "r");
		if (!in)
			die_errno("cannot open '%s'", inpath);
	}

	if (strbuf_read(&input, fileno(in), 0) < 0)
		die_errno("could not read input file");

	if (message)
		strbuf_addstr(&output, message);

	memset(&opts, 0, sizeof(opts));
	opts.add_title = !message;
	opts.credit_people = 1;
	opts.shortlog_len = shortlog_len;

	ret = fmt_merge_msg(&input, &output, &opts);
	if (ret)
		return ret;
	write_in_full(STDOUT_FILENO, output.buf, output.len);
	return 0;
}