trailer: add tests for "git interpret-trailers"
[git/git.git] / trailer.c
CommitLineData
9385b5d7 1#include "cache.h"
f0a90b4e 2#include "string-list.h"
b1d78d77 3#include "trailer.h"
9385b5d7
CC
4/*
5 * Copyright (c) 2013, 2014 Christian Couder <chriscool@tuxfamily.org>
6 */
7
8enum action_where { WHERE_END, WHERE_AFTER, WHERE_BEFORE, WHERE_START };
9enum action_if_exists { EXISTS_ADD_IF_DIFFERENT_NEIGHBOR, EXISTS_ADD_IF_DIFFERENT,
10 EXISTS_ADD, EXISTS_REPLACE, EXISTS_DO_NOTHING };
11enum action_if_missing { MISSING_ADD, MISSING_DO_NOTHING };
12
13struct conf_info {
14 char *name;
15 char *key;
16 char *command;
17 enum action_where where;
18 enum action_if_exists if_exists;
19 enum action_if_missing if_missing;
20};
21
22static struct conf_info default_conf_info;
23
24struct trailer_item {
25 struct trailer_item *previous;
26 struct trailer_item *next;
27 const char *token;
28 const char *value;
29 struct conf_info conf;
30};
31
32static struct trailer_item *first_conf_item;
33
34static char *separators = ":";
35
36static int after_or_end(enum action_where where)
37{
38 return (where == WHERE_AFTER) || (where == WHERE_END);
39}
40
41/*
42 * Return the length of the string not including any final
43 * punctuation. E.g., the input "Signed-off-by:" would return
44 * 13, stripping the trailing punctuation but retaining
45 * internal punctuation.
46 */
47static size_t token_len_without_separator(const char *token, size_t len)
48{
49 while (len > 0 && !isalnum(token[len - 1]))
50 len--;
51 return len;
52}
53
54static int same_token(struct trailer_item *a, struct trailer_item *b)
55{
56 size_t a_len = token_len_without_separator(a->token, strlen(a->token));
57 size_t b_len = token_len_without_separator(b->token, strlen(b->token));
58 size_t min_len = (a_len > b_len) ? b_len : a_len;
59
60 return !strncasecmp(a->token, b->token, min_len);
61}
62
63static int same_value(struct trailer_item *a, struct trailer_item *b)
64{
65 return !strcasecmp(a->value, b->value);
66}
67
68static int same_trailer(struct trailer_item *a, struct trailer_item *b)
69{
70 return same_token(a, b) && same_value(a, b);
71}
4103818d 72
2013d850
CC
73static inline int contains_only_spaces(const char *str)
74{
75 const char *s = str;
76 while (*s && isspace(*s))
77 s++;
78 return !*s;
79}
80
4103818d
CC
81static void free_trailer_item(struct trailer_item *item)
82{
83 free(item->conf.name);
84 free(item->conf.key);
85 free(item->conf.command);
86 free((char *)item->token);
87 free((char *)item->value);
88 free(item);
89}
90
b1d78d77
CC
91static char last_non_space_char(const char *s)
92{
93 int i;
94 for (i = strlen(s) - 1; i >= 0; i--)
95 if (!isspace(s[i]))
96 return s[i];
97 return '\0';
98}
99
100static void print_tok_val(const char *tok, const char *val)
101{
102 char c = last_non_space_char(tok);
103 if (!c)
104 return;
105 if (strchr(separators, c))
106 printf("%s%s\n", tok, val);
107 else
108 printf("%s%c %s\n", tok, separators[0], val);
109}
110
111static void print_all(struct trailer_item *first, int trim_empty)
112{
113 struct trailer_item *item;
114 for (item = first; item; item = item->next) {
115 if (!trim_empty || strlen(item->value) > 0)
116 print_tok_val(item->token, item->value);
117 }
118}
119
4103818d
CC
120static void update_last(struct trailer_item **last)
121{
122 if (*last)
123 while ((*last)->next != NULL)
124 *last = (*last)->next;
125}
126
127static void update_first(struct trailer_item **first)
128{
129 if (*first)
130 while ((*first)->previous != NULL)
131 *first = (*first)->previous;
132}
133
134static void add_arg_to_input_list(struct trailer_item *on_tok,
135 struct trailer_item *arg_tok,
136 struct trailer_item **first,
137 struct trailer_item **last)
138{
139 if (after_or_end(arg_tok->conf.where)) {
140 arg_tok->next = on_tok->next;
141 on_tok->next = arg_tok;
142 arg_tok->previous = on_tok;
143 if (arg_tok->next)
144 arg_tok->next->previous = arg_tok;
145 update_last(last);
146 } else {
147 arg_tok->previous = on_tok->previous;
148 on_tok->previous = arg_tok;
149 arg_tok->next = on_tok;
150 if (arg_tok->previous)
151 arg_tok->previous->next = arg_tok;
152 update_first(first);
153 }
154}
155
156static int check_if_different(struct trailer_item *in_tok,
157 struct trailer_item *arg_tok,
158 int check_all)
159{
160 enum action_where where = arg_tok->conf.where;
161 do {
162 if (!in_tok)
163 return 1;
164 if (same_trailer(in_tok, arg_tok))
165 return 0;
166 /*
167 * if we want to add a trailer after another one,
168 * we have to check those before this one
169 */
170 in_tok = after_or_end(where) ? in_tok->previous : in_tok->next;
171 } while (check_all);
172 return 1;
173}
174
175static void remove_from_list(struct trailer_item *item,
176 struct trailer_item **first,
177 struct trailer_item **last)
178{
179 struct trailer_item *next = item->next;
180 struct trailer_item *previous = item->previous;
181
182 if (next) {
183 item->next->previous = previous;
184 item->next = NULL;
185 } else if (last)
186 *last = previous;
187
188 if (previous) {
189 item->previous->next = next;
190 item->previous = NULL;
191 } else if (first)
192 *first = next;
193}
194
195static struct trailer_item *remove_first(struct trailer_item **first)
196{
197 struct trailer_item *item = *first;
198 *first = item->next;
199 if (item->next) {
200 item->next->previous = NULL;
201 item->next = NULL;
202 }
203 return item;
204}
205
206static void apply_arg_if_exists(struct trailer_item *in_tok,
207 struct trailer_item *arg_tok,
208 struct trailer_item *on_tok,
209 struct trailer_item **in_tok_first,
210 struct trailer_item **in_tok_last)
211{
212 switch (arg_tok->conf.if_exists) {
213 case EXISTS_DO_NOTHING:
214 free_trailer_item(arg_tok);
215 break;
216 case EXISTS_REPLACE:
217 add_arg_to_input_list(on_tok, arg_tok,
218 in_tok_first, in_tok_last);
219 remove_from_list(in_tok, in_tok_first, in_tok_last);
220 free_trailer_item(in_tok);
221 break;
222 case EXISTS_ADD:
223 add_arg_to_input_list(on_tok, arg_tok,
224 in_tok_first, in_tok_last);
225 break;
226 case EXISTS_ADD_IF_DIFFERENT:
227 if (check_if_different(in_tok, arg_tok, 1))
228 add_arg_to_input_list(on_tok, arg_tok,
229 in_tok_first, in_tok_last);
230 else
231 free_trailer_item(arg_tok);
232 break;
233 case EXISTS_ADD_IF_DIFFERENT_NEIGHBOR:
234 if (check_if_different(on_tok, arg_tok, 0))
235 add_arg_to_input_list(on_tok, arg_tok,
236 in_tok_first, in_tok_last);
237 else
238 free_trailer_item(arg_tok);
239 break;
240 }
241}
242
243static void apply_arg_if_missing(struct trailer_item **in_tok_first,
244 struct trailer_item **in_tok_last,
245 struct trailer_item *arg_tok)
246{
247 struct trailer_item **in_tok;
248 enum action_where where;
249
250 switch (arg_tok->conf.if_missing) {
251 case MISSING_DO_NOTHING:
252 free_trailer_item(arg_tok);
253 break;
254 case MISSING_ADD:
255 where = arg_tok->conf.where;
256 in_tok = after_or_end(where) ? in_tok_last : in_tok_first;
257 if (*in_tok) {
258 add_arg_to_input_list(*in_tok, arg_tok,
259 in_tok_first, in_tok_last);
260 } else {
261 *in_tok_first = arg_tok;
262 *in_tok_last = arg_tok;
263 }
264 break;
265 }
266}
267
268static int find_same_and_apply_arg(struct trailer_item **in_tok_first,
269 struct trailer_item **in_tok_last,
270 struct trailer_item *arg_tok)
271{
272 struct trailer_item *in_tok;
273 struct trailer_item *on_tok;
274 struct trailer_item *following_tok;
275
276 enum action_where where = arg_tok->conf.where;
277 int middle = (where == WHERE_AFTER) || (where == WHERE_BEFORE);
278 int backwards = after_or_end(where);
279 struct trailer_item *start_tok = backwards ? *in_tok_last : *in_tok_first;
280
281 for (in_tok = start_tok; in_tok; in_tok = following_tok) {
282 following_tok = backwards ? in_tok->previous : in_tok->next;
283 if (!same_token(in_tok, arg_tok))
284 continue;
285 on_tok = middle ? in_tok : start_tok;
286 apply_arg_if_exists(in_tok, arg_tok, on_tok,
287 in_tok_first, in_tok_last);
288 return 1;
289 }
290 return 0;
291}
292
293static void process_trailers_lists(struct trailer_item **in_tok_first,
294 struct trailer_item **in_tok_last,
295 struct trailer_item **arg_tok_first)
296{
297 struct trailer_item *arg_tok;
298 struct trailer_item *next_arg;
299
300 if (!*arg_tok_first)
301 return;
302
303 for (arg_tok = *arg_tok_first; arg_tok; arg_tok = next_arg) {
304 int applied = 0;
305
306 next_arg = arg_tok->next;
307 remove_from_list(arg_tok, arg_tok_first, NULL);
308
309 applied = find_same_and_apply_arg(in_tok_first,
310 in_tok_last,
311 arg_tok);
312
313 if (!applied)
314 apply_arg_if_missing(in_tok_first,
315 in_tok_last,
316 arg_tok);
317 }
318}
46a0613f
CC
319
320static int set_where(struct conf_info *item, const char *value)
321{
322 if (!strcasecmp("after", value))
323 item->where = WHERE_AFTER;
324 else if (!strcasecmp("before", value))
325 item->where = WHERE_BEFORE;
326 else if (!strcasecmp("end", value))
327 item->where = WHERE_END;
328 else if (!strcasecmp("start", value))
329 item->where = WHERE_START;
330 else
331 return -1;
332 return 0;
333}
334
335static int set_if_exists(struct conf_info *item, const char *value)
336{
337 if (!strcasecmp("addIfDifferent", value))
338 item->if_exists = EXISTS_ADD_IF_DIFFERENT;
339 else if (!strcasecmp("addIfDifferentNeighbor", value))
340 item->if_exists = EXISTS_ADD_IF_DIFFERENT_NEIGHBOR;
341 else if (!strcasecmp("add", value))
342 item->if_exists = EXISTS_ADD;
343 else if (!strcasecmp("replace", value))
344 item->if_exists = EXISTS_REPLACE;
345 else if (!strcasecmp("doNothing", value))
346 item->if_exists = EXISTS_DO_NOTHING;
347 else
348 return -1;
349 return 0;
350}
351
352static int set_if_missing(struct conf_info *item, const char *value)
353{
354 if (!strcasecmp("doNothing", value))
355 item->if_missing = MISSING_DO_NOTHING;
356 else if (!strcasecmp("add", value))
357 item->if_missing = MISSING_ADD;
358 else
359 return -1;
360 return 0;
361}
362
363static void duplicate_conf(struct conf_info *dst, struct conf_info *src)
364{
365 *dst = *src;
366 if (src->name)
367 dst->name = xstrdup(src->name);
368 if (src->key)
369 dst->key = xstrdup(src->key);
370 if (src->command)
371 dst->command = xstrdup(src->command);
372}
373
374static struct trailer_item *get_conf_item(const char *name)
375{
376 struct trailer_item *item;
377 struct trailer_item *previous;
378
379 /* Look up item with same name */
380 for (previous = NULL, item = first_conf_item;
381 item;
382 previous = item, item = item->next) {
383 if (!strcasecmp(item->conf.name, name))
384 return item;
385 }
386
387 /* Item does not already exists, create it */
388 item = xcalloc(sizeof(struct trailer_item), 1);
389 duplicate_conf(&item->conf, &default_conf_info);
390 item->conf.name = xstrdup(name);
391
392 if (!previous)
393 first_conf_item = item;
394 else {
395 previous->next = item;
396 item->previous = previous;
397 }
398
399 return item;
400}
401
402enum trailer_info_type { TRAILER_KEY, TRAILER_COMMAND, TRAILER_WHERE,
403 TRAILER_IF_EXISTS, TRAILER_IF_MISSING };
404
405static struct {
406 const char *name;
407 enum trailer_info_type type;
408} trailer_config_items[] = {
409 { "key", TRAILER_KEY },
410 { "command", TRAILER_COMMAND },
411 { "where", TRAILER_WHERE },
412 { "ifexists", TRAILER_IF_EXISTS },
413 { "ifmissing", TRAILER_IF_MISSING }
414};
415
416static int git_trailer_default_config(const char *conf_key, const char *value, void *cb)
417{
418 const char *trailer_item, *variable_name;
419
420 if (!skip_prefix(conf_key, "trailer.", &trailer_item))
421 return 0;
422
423 variable_name = strrchr(trailer_item, '.');
424 if (!variable_name) {
425 if (!strcmp(trailer_item, "where")) {
426 if (set_where(&default_conf_info, value) < 0)
427 warning(_("unknown value '%s' for key '%s'"),
428 value, conf_key);
429 } else if (!strcmp(trailer_item, "ifexists")) {
430 if (set_if_exists(&default_conf_info, value) < 0)
431 warning(_("unknown value '%s' for key '%s'"),
432 value, conf_key);
433 } else if (!strcmp(trailer_item, "ifmissing")) {
434 if (set_if_missing(&default_conf_info, value) < 0)
435 warning(_("unknown value '%s' for key '%s'"),
436 value, conf_key);
437 } else if (!strcmp(trailer_item, "separators")) {
438 separators = xstrdup(value);
439 }
440 }
441 return 0;
442}
443
444static int git_trailer_config(const char *conf_key, const char *value, void *cb)
445{
446 const char *trailer_item, *variable_name;
447 struct trailer_item *item;
448 struct conf_info *conf;
449 char *name = NULL;
450 enum trailer_info_type type;
451 int i;
452
453 if (!skip_prefix(conf_key, "trailer.", &trailer_item))
454 return 0;
455
456 variable_name = strrchr(trailer_item, '.');
457 if (!variable_name)
458 return 0;
459
460 variable_name++;
461 for (i = 0; i < ARRAY_SIZE(trailer_config_items); i++) {
462 if (strcmp(trailer_config_items[i].name, variable_name))
463 continue;
464 name = xstrndup(trailer_item, variable_name - trailer_item - 1);
465 type = trailer_config_items[i].type;
466 break;
467 }
468
469 if (!name)
470 return 0;
471
472 item = get_conf_item(name);
473 conf = &item->conf;
474 free(name);
475
476 switch (type) {
477 case TRAILER_KEY:
478 if (conf->key)
479 warning(_("more than one %s"), conf_key);
480 conf->key = xstrdup(value);
481 break;
482 case TRAILER_COMMAND:
483 if (conf->command)
484 warning(_("more than one %s"), conf_key);
485 conf->command = xstrdup(value);
486 break;
487 case TRAILER_WHERE:
488 if (set_where(conf, value))
489 warning(_("unknown value '%s' for key '%s'"), value, conf_key);
490 break;
491 case TRAILER_IF_EXISTS:
492 if (set_if_exists(conf, value))
493 warning(_("unknown value '%s' for key '%s'"), value, conf_key);
494 break;
495 case TRAILER_IF_MISSING:
496 if (set_if_missing(conf, value))
497 warning(_("unknown value '%s' for key '%s'"), value, conf_key);
498 break;
499 default:
500 die("internal bug in trailer.c");
501 }
502 return 0;
503}
f0a90b4e
CC
504
505static int parse_trailer(struct strbuf *tok, struct strbuf *val, const char *trailer)
506{
507 size_t len;
508 struct strbuf seps = STRBUF_INIT;
509 strbuf_addstr(&seps, separators);
510 strbuf_addch(&seps, '=');
511 len = strcspn(trailer, seps.buf);
512 strbuf_release(&seps);
513 if (len == 0)
514 return error(_("empty trailer token in trailer '%s'"), trailer);
515 if (len < strlen(trailer)) {
516 strbuf_add(tok, trailer, len);
517 strbuf_trim(tok);
518 strbuf_addstr(val, trailer + len + 1);
519 strbuf_trim(val);
520 } else {
521 strbuf_addstr(tok, trailer);
522 strbuf_trim(tok);
523 }
524 return 0;
525}
526
527static const char *token_from_item(struct trailer_item *item, char *tok)
528{
529 if (item->conf.key)
530 return item->conf.key;
531 if (tok)
532 return tok;
533 return item->conf.name;
534}
535
536static struct trailer_item *new_trailer_item(struct trailer_item *conf_item,
537 char *tok, char *val)
538{
539 struct trailer_item *new = xcalloc(sizeof(*new), 1);
540 new->value = val;
541
542 if (conf_item) {
543 duplicate_conf(&new->conf, &conf_item->conf);
544 new->token = xstrdup(token_from_item(conf_item, tok));
545 free(tok);
546 } else {
547 duplicate_conf(&new->conf, &default_conf_info);
548 new->token = tok;
549 }
550
551 return new;
552}
553
554static int token_matches_item(const char *tok, struct trailer_item *item, int tok_len)
555{
556 if (!strncasecmp(tok, item->conf.name, tok_len))
557 return 1;
558 return item->conf.key ? !strncasecmp(tok, item->conf.key, tok_len) : 0;
559}
560
561static struct trailer_item *create_trailer_item(const char *string)
562{
563 struct strbuf tok = STRBUF_INIT;
564 struct strbuf val = STRBUF_INIT;
565 struct trailer_item *item;
566 int tok_len;
567
568 if (parse_trailer(&tok, &val, string))
569 return NULL;
570
571 tok_len = token_len_without_separator(tok.buf, tok.len);
572
573 /* Lookup if the token matches something in the config */
574 for (item = first_conf_item; item; item = item->next) {
575 if (token_matches_item(tok.buf, item, tok_len))
576 return new_trailer_item(item,
577 strbuf_detach(&tok, NULL),
578 strbuf_detach(&val, NULL));
579 }
580
581 return new_trailer_item(NULL,
582 strbuf_detach(&tok, NULL),
583 strbuf_detach(&val, NULL));
584}
585
586static void add_trailer_item(struct trailer_item **first,
587 struct trailer_item **last,
588 struct trailer_item *new)
589{
590 if (!new)
591 return;
592 if (!*last) {
593 *first = new;
594 *last = new;
595 } else {
596 (*last)->next = new;
597 new->previous = *last;
598 *last = new;
599 }
600}
601
602static struct trailer_item *process_command_line_args(struct string_list *trailers)
603{
604 struct trailer_item *arg_tok_first = NULL;
605 struct trailer_item *arg_tok_last = NULL;
606 struct string_list_item *tr;
607
608 for_each_string_list_item(tr, trailers) {
609 struct trailer_item *new = create_trailer_item(tr->string);
610 add_trailer_item(&arg_tok_first, &arg_tok_last, new);
611 }
612
613 return arg_tok_first;
614}
2013d850
CC
615
616static struct strbuf **read_input_file(const char *file)
617{
618 struct strbuf **lines;
619 struct strbuf sb = STRBUF_INIT;
620
621 if (file) {
622 if (strbuf_read_file(&sb, file, 0) < 0)
623 die_errno(_("could not read input file '%s'"), file);
624 } else {
625 if (strbuf_read(&sb, fileno(stdin), 0) < 0)
626 die_errno(_("could not read from stdin"));
627 }
628
629 lines = strbuf_split(&sb, '\n');
630
631 strbuf_release(&sb);
632
633 return lines;
634}
635
636/*
637 * Return the (0 based) index of the start of the patch or the line
638 * count if there is no patch in the message.
639 */
640static int find_patch_start(struct strbuf **lines, int count)
641{
642 int i;
643
644 /* Get the start of the patch part if any */
645 for (i = 0; i < count; i++) {
646 if (starts_with(lines[i]->buf, "---"))
647 return i;
648 }
649
650 return count;
651}
652
653/*
654 * Return the (0 based) index of the first trailer line or count if
655 * there are no trailers. Trailers are searched only in the lines from
656 * index (count - 1) down to index 0.
657 */
658static int find_trailer_start(struct strbuf **lines, int count)
659{
660 int start, only_spaces = 1;
661
662 /*
663 * Get the start of the trailers by looking starting from the end
664 * for a line with only spaces before lines with one separator.
665 */
666 for (start = count - 1; start >= 0; start--) {
667 if (lines[start]->buf[0] == comment_line_char)
668 continue;
669 if (contains_only_spaces(lines[start]->buf)) {
670 if (only_spaces)
671 continue;
672 return start + 1;
673 }
674 if (strcspn(lines[start]->buf, separators) < lines[start]->len) {
675 if (only_spaces)
676 only_spaces = 0;
677 continue;
678 }
679 return count;
680 }
681
682 return only_spaces ? count : 0;
683}
684
685static int has_blank_line_before(struct strbuf **lines, int start)
686{
687 for (;start >= 0; start--) {
688 if (lines[start]->buf[0] == comment_line_char)
689 continue;
690 return contains_only_spaces(lines[start]->buf);
691 }
692 return 0;
693}
694
695static void print_lines(struct strbuf **lines, int start, int end)
696{
697 int i;
698 for (i = start; lines[i] && i < end; i++)
699 printf("%s", lines[i]->buf);
700}
701
702static int process_input_file(struct strbuf **lines,
703 struct trailer_item **in_tok_first,
704 struct trailer_item **in_tok_last)
705{
706 int count = 0;
707 int patch_start, trailer_start, i;
708
709 /* Get the line count */
710 while (lines[count])
711 count++;
712
713 patch_start = find_patch_start(lines, count);
714 trailer_start = find_trailer_start(lines, patch_start);
715
716 /* Print lines before the trailers as is */
717 print_lines(lines, 0, trailer_start);
718
719 if (!has_blank_line_before(lines, trailer_start - 1))
720 printf("\n");
721
722 /* Parse trailer lines */
723 for (i = trailer_start; i < patch_start; i++) {
724 struct trailer_item *new = create_trailer_item(lines[i]->buf);
725 add_trailer_item(in_tok_first, in_tok_last, new);
726 }
727
728 return patch_start;
729}
b1d78d77
CC
730
731static void free_all(struct trailer_item **first)
732{
733 while (*first) {
734 struct trailer_item *item = remove_first(first);
735 free_trailer_item(item);
736 }
737}
738
739void process_trailers(const char *file, int trim_empty, struct string_list *trailers)
740{
741 struct trailer_item *in_tok_first = NULL;
742 struct trailer_item *in_tok_last = NULL;
743 struct trailer_item *arg_tok_first;
744 struct strbuf **lines;
745 int patch_start;
746
747 /* Default config must be setup first */
748 git_config(git_trailer_default_config, NULL);
749 git_config(git_trailer_config, NULL);
750
751 lines = read_input_file(file);
752
753 /* Print the lines before the trailers */
754 patch_start = process_input_file(lines, &in_tok_first, &in_tok_last);
755
756 arg_tok_first = process_command_line_args(trailers);
757
758 process_trailers_lists(&in_tok_first, &in_tok_last, &arg_tok_first);
759
760 print_all(in_tok_first, trim_empty);
761
762 free_all(&in_tok_first);
763
764 /* Print the lines after the trailers as is */
765 print_lines(lines, patch_start, INT_MAX);
766
767 strbuf_list_free(lines);
768}