transport-helper: drop read/write errno checks
[git.git] / attr.c
blobeaece6658d64b2129332ffab39e30485730f3306
1 /*
2 * Handle git attributes. See gitattributes(5) for a description of
3 * the file syntax, and Documentation/technical/api-gitattributes.txt
4 * for a description of the API.
6 * One basic design decision here is that we are not going to support
7 * an insanely large number of attributes.
8 */
10 #define NO_THE_INDEX_COMPATIBILITY_MACROS
11 #include "cache.h"
12 #include "config.h"
13 #include "exec-cmd.h"
14 #include "attr.h"
15 #include "dir.h"
16 #include "utf8.h"
17 #include "quote.h"
18 #include "thread-utils.h"
20 const char git_attr__true[] = "(builtin)true";
21 const char git_attr__false[] = "\0(builtin)false";
22 static const char git_attr__unknown[] = "(builtin)unknown";
23 #define ATTR__TRUE git_attr__true
24 #define ATTR__FALSE git_attr__false
25 #define ATTR__UNSET NULL
26 #define ATTR__UNKNOWN git_attr__unknown
28 #ifndef DEBUG_ATTR
29 #define DEBUG_ATTR 0
30 #endif
32 struct git_attr {
33 int attr_nr; /* unique attribute number */
34 char name[FLEX_ARRAY]; /* attribute name */
37 const char *git_attr_name(const struct git_attr *attr)
39 return attr->name;
42 struct attr_hashmap {
43 struct hashmap map;
44 pthread_mutex_t mutex;
47 static inline void hashmap_lock(struct attr_hashmap *map)
49 pthread_mutex_lock(&map->mutex);
52 static inline void hashmap_unlock(struct attr_hashmap *map)
54 pthread_mutex_unlock(&map->mutex);
58 * The global dictionary of all interned attributes. This
59 * is a singleton object which is shared between threads.
60 * Access to this dictionary must be surrounded with a mutex.
62 static struct attr_hashmap g_attr_hashmap;
64 /* The container for objects stored in "struct attr_hashmap" */
65 struct attr_hash_entry {
66 struct hashmap_entry ent; /* must be the first member! */
67 const char *key; /* the key; memory should be owned by value */
68 size_t keylen; /* length of the key */
69 void *value; /* the stored value */
72 /* attr_hashmap comparison function */
73 static int attr_hash_entry_cmp(const void *unused_cmp_data,
74 const void *entry,
75 const void *entry_or_key,
76 const void *unused_keydata)
78 const struct attr_hash_entry *a = entry;
79 const struct attr_hash_entry *b = entry_or_key;
80 return (a->keylen != b->keylen) || strncmp(a->key, b->key, a->keylen);
83 /* Initialize an 'attr_hashmap' object */
84 static void attr_hashmap_init(struct attr_hashmap *map)
86 hashmap_init(&map->map, attr_hash_entry_cmp, NULL, 0);
90 * Retrieve the 'value' stored in a hashmap given the provided 'key'.
91 * If there is no matching entry, return NULL.
93 static void *attr_hashmap_get(struct attr_hashmap *map,
94 const char *key, size_t keylen)
96 struct attr_hash_entry k;
97 struct attr_hash_entry *e;
99 if (!map->map.tablesize)
100 attr_hashmap_init(map);
102 hashmap_entry_init(&k, memhash(key, keylen));
103 k.key = key;
104 k.keylen = keylen;
105 e = hashmap_get(&map->map, &k, NULL);
107 return e ? e->value : NULL;
110 /* Add 'value' to a hashmap based on the provided 'key'. */
111 static void attr_hashmap_add(struct attr_hashmap *map,
112 const char *key, size_t keylen,
113 void *value)
115 struct attr_hash_entry *e;
117 if (!map->map.tablesize)
118 attr_hashmap_init(map);
120 e = xmalloc(sizeof(struct attr_hash_entry));
121 hashmap_entry_init(e, memhash(key, keylen));
122 e->key = key;
123 e->keylen = keylen;
124 e->value = value;
126 hashmap_add(&map->map, e);
129 struct all_attrs_item {
130 const struct git_attr *attr;
131 const char *value;
133 * If 'macro' is non-NULL, indicates that 'attr' is a macro based on
134 * the current attribute stack and contains a pointer to the match_attr
135 * definition of the macro
137 const struct match_attr *macro;
141 * Reallocate and reinitialize the array of all attributes (which is used in
142 * the attribute collection process) in 'check' based on the global dictionary
143 * of attributes.
145 static void all_attrs_init(struct attr_hashmap *map, struct attr_check *check)
147 int i;
148 unsigned int size;
150 hashmap_lock(map);
152 size = hashmap_get_size(&map->map);
153 if (size < check->all_attrs_nr)
154 BUG("interned attributes shouldn't be deleted");
157 * If the number of attributes in the global dictionary has increased
158 * (or this attr_check instance doesn't have an initialized all_attrs
159 * field), reallocate the provided attr_check instance's all_attrs
160 * field and fill each entry with its corresponding git_attr.
162 if (size != check->all_attrs_nr) {
163 struct attr_hash_entry *e;
164 struct hashmap_iter iter;
165 hashmap_iter_init(&map->map, &iter);
167 REALLOC_ARRAY(check->all_attrs, size);
168 check->all_attrs_nr = size;
170 while ((e = hashmap_iter_next(&iter))) {
171 const struct git_attr *a = e->value;
172 check->all_attrs[a->attr_nr].attr = a;
176 hashmap_unlock(map);
179 * Re-initialize every entry in check->all_attrs.
180 * This re-initialization can live outside of the locked region since
181 * the attribute dictionary is no longer being accessed.
183 for (i = 0; i < check->all_attrs_nr; i++) {
184 check->all_attrs[i].value = ATTR__UNKNOWN;
185 check->all_attrs[i].macro = NULL;
189 static int attr_name_valid(const char *name, size_t namelen)
192 * Attribute name cannot begin with '-' and must consist of
193 * characters from [-A-Za-z0-9_.].
195 if (namelen <= 0 || *name == '-')
196 return 0;
197 while (namelen--) {
198 char ch = *name++;
199 if (! (ch == '-' || ch == '.' || ch == '_' ||
200 ('0' <= ch && ch <= '9') ||
201 ('a' <= ch && ch <= 'z') ||
202 ('A' <= ch && ch <= 'Z')) )
203 return 0;
205 return 1;
208 static void report_invalid_attr(const char *name, size_t len,
209 const char *src, int lineno)
211 struct strbuf err = STRBUF_INIT;
212 strbuf_addf(&err, _("%.*s is not a valid attribute name"),
213 (int) len, name);
214 fprintf(stderr, "%s: %s:%d\n", err.buf, src, lineno);
215 strbuf_release(&err);
219 * Given a 'name', lookup and return the corresponding attribute in the global
220 * dictionary. If no entry is found, create a new attribute and store it in
221 * the dictionary.
223 static const struct git_attr *git_attr_internal(const char *name, int namelen)
225 struct git_attr *a;
227 if (!attr_name_valid(name, namelen))
228 return NULL;
230 hashmap_lock(&g_attr_hashmap);
232 a = attr_hashmap_get(&g_attr_hashmap, name, namelen);
234 if (!a) {
235 FLEX_ALLOC_MEM(a, name, name, namelen);
236 a->attr_nr = hashmap_get_size(&g_attr_hashmap.map);
238 attr_hashmap_add(&g_attr_hashmap, a->name, namelen, a);
239 assert(a->attr_nr ==
240 (hashmap_get_size(&g_attr_hashmap.map) - 1));
243 hashmap_unlock(&g_attr_hashmap);
245 return a;
248 const struct git_attr *git_attr(const char *name)
250 return git_attr_internal(name, strlen(name));
253 /* What does a matched pattern decide? */
254 struct attr_state {
255 const struct git_attr *attr;
256 const char *setto;
259 struct pattern {
260 const char *pattern;
261 int patternlen;
262 int nowildcardlen;
263 unsigned flags; /* EXC_FLAG_* */
267 * One rule, as from a .gitattributes file.
269 * If is_macro is true, then u.attr is a pointer to the git_attr being
270 * defined.
272 * If is_macro is false, then u.pat is the filename pattern to which the
273 * rule applies.
275 * In either case, num_attr is the number of attributes affected by
276 * this rule, and state is an array listing them. The attributes are
277 * listed as they appear in the file (macros unexpanded).
279 struct match_attr {
280 union {
281 struct pattern pat;
282 const struct git_attr *attr;
283 } u;
284 char is_macro;
285 unsigned num_attr;
286 struct attr_state state[FLEX_ARRAY];
289 static const char blank[] = " \t\r\n";
292 * Parse a whitespace-delimited attribute state (i.e., "attr",
293 * "-attr", "!attr", or "attr=value") from the string starting at src.
294 * If e is not NULL, write the results to *e. Return a pointer to the
295 * remainder of the string (with leading whitespace removed), or NULL
296 * if there was an error.
298 static const char *parse_attr(const char *src, int lineno, const char *cp,
299 struct attr_state *e)
301 const char *ep, *equals;
302 int len;
304 ep = cp + strcspn(cp, blank);
305 equals = strchr(cp, '=');
306 if (equals && ep < equals)
307 equals = NULL;
308 if (equals)
309 len = equals - cp;
310 else
311 len = ep - cp;
312 if (!e) {
313 if (*cp == '-' || *cp == '!') {
314 cp++;
315 len--;
317 if (!attr_name_valid(cp, len)) {
318 report_invalid_attr(cp, len, src, lineno);
319 return NULL;
321 } else {
323 * As this function is always called twice, once with
324 * e == NULL in the first pass and then e != NULL in
325 * the second pass, no need for attr_name_valid()
326 * check here.
328 if (*cp == '-' || *cp == '!') {
329 e->setto = (*cp == '-') ? ATTR__FALSE : ATTR__UNSET;
330 cp++;
331 len--;
333 else if (!equals)
334 e->setto = ATTR__TRUE;
335 else {
336 e->setto = xmemdupz(equals + 1, ep - equals - 1);
338 e->attr = git_attr_internal(cp, len);
340 return ep + strspn(ep, blank);
343 static struct match_attr *parse_attr_line(const char *line, const char *src,
344 int lineno, int macro_ok)
346 int namelen;
347 int num_attr, i;
348 const char *cp, *name, *states;
349 struct match_attr *res = NULL;
350 int is_macro;
351 struct strbuf pattern = STRBUF_INIT;
353 cp = line + strspn(line, blank);
354 if (!*cp || *cp == '#')
355 return NULL;
356 name = cp;
358 if (*cp == '"' && !unquote_c_style(&pattern, name, &states)) {
359 name = pattern.buf;
360 namelen = pattern.len;
361 } else {
362 namelen = strcspn(name, blank);
363 states = name + namelen;
366 if (strlen(ATTRIBUTE_MACRO_PREFIX) < namelen &&
367 starts_with(name, ATTRIBUTE_MACRO_PREFIX)) {
368 if (!macro_ok) {
369 fprintf(stderr, "%s not allowed: %s:%d\n",
370 name, src, lineno);
371 goto fail_return;
373 is_macro = 1;
374 name += strlen(ATTRIBUTE_MACRO_PREFIX);
375 name += strspn(name, blank);
376 namelen = strcspn(name, blank);
377 if (!attr_name_valid(name, namelen)) {
378 report_invalid_attr(name, namelen, src, lineno);
379 goto fail_return;
382 else
383 is_macro = 0;
385 states += strspn(states, blank);
387 /* First pass to count the attr_states */
388 for (cp = states, num_attr = 0; *cp; num_attr++) {
389 cp = parse_attr(src, lineno, cp, NULL);
390 if (!cp)
391 goto fail_return;
394 res = xcalloc(1,
395 sizeof(*res) +
396 sizeof(struct attr_state) * num_attr +
397 (is_macro ? 0 : namelen + 1));
398 if (is_macro) {
399 res->u.attr = git_attr_internal(name, namelen);
400 } else {
401 char *p = (char *)&(res->state[num_attr]);
402 memcpy(p, name, namelen);
403 res->u.pat.pattern = p;
404 parse_exclude_pattern(&res->u.pat.pattern,
405 &res->u.pat.patternlen,
406 &res->u.pat.flags,
407 &res->u.pat.nowildcardlen);
408 if (res->u.pat.flags & EXC_FLAG_NEGATIVE) {
409 warning(_("Negative patterns are ignored in git attributes\n"
410 "Use '\\!' for literal leading exclamation."));
411 goto fail_return;
414 res->is_macro = is_macro;
415 res->num_attr = num_attr;
417 /* Second pass to fill the attr_states */
418 for (cp = states, i = 0; *cp; i++) {
419 cp = parse_attr(src, lineno, cp, &(res->state[i]));
422 strbuf_release(&pattern);
423 return res;
425 fail_return:
426 strbuf_release(&pattern);
427 free(res);
428 return NULL;
432 * Like info/exclude and .gitignore, the attribute information can
433 * come from many places.
435 * (1) .gitattribute file of the same directory;
436 * (2) .gitattribute file of the parent directory if (1) does not have
437 * any match; this goes recursively upwards, just like .gitignore.
438 * (3) $GIT_DIR/info/attributes, which overrides both of the above.
440 * In the same file, later entries override the earlier match, so in the
441 * global list, we would have entries from info/attributes the earliest
442 * (reading the file from top to bottom), .gitattribute of the root
443 * directory (again, reading the file from top to bottom) down to the
444 * current directory, and then scan the list backwards to find the first match.
445 * This is exactly the same as what is_excluded() does in dir.c to deal with
446 * .gitignore file and info/excludes file as a fallback.
449 struct attr_stack {
450 struct attr_stack *prev;
451 char *origin;
452 size_t originlen;
453 unsigned num_matches;
454 unsigned alloc;
455 struct match_attr **attrs;
458 static void attr_stack_free(struct attr_stack *e)
460 int i;
461 free(e->origin);
462 for (i = 0; i < e->num_matches; i++) {
463 struct match_attr *a = e->attrs[i];
464 int j;
465 for (j = 0; j < a->num_attr; j++) {
466 const char *setto = a->state[j].setto;
467 if (setto == ATTR__TRUE ||
468 setto == ATTR__FALSE ||
469 setto == ATTR__UNSET ||
470 setto == ATTR__UNKNOWN)
472 else
473 free((char *) setto);
475 free(a);
477 free(e->attrs);
478 free(e);
481 static void drop_attr_stack(struct attr_stack **stack)
483 while (*stack) {
484 struct attr_stack *elem = *stack;
485 *stack = elem->prev;
486 attr_stack_free(elem);
490 /* List of all attr_check structs; access should be surrounded by mutex */
491 static struct check_vector {
492 size_t nr;
493 size_t alloc;
494 struct attr_check **checks;
495 pthread_mutex_t mutex;
496 } check_vector;
498 static inline void vector_lock(void)
500 pthread_mutex_lock(&check_vector.mutex);
503 static inline void vector_unlock(void)
505 pthread_mutex_unlock(&check_vector.mutex);
508 static void check_vector_add(struct attr_check *c)
510 vector_lock();
512 ALLOC_GROW(check_vector.checks,
513 check_vector.nr + 1,
514 check_vector.alloc);
515 check_vector.checks[check_vector.nr++] = c;
517 vector_unlock();
520 static void check_vector_remove(struct attr_check *check)
522 int i;
524 vector_lock();
526 /* Find entry */
527 for (i = 0; i < check_vector.nr; i++)
528 if (check_vector.checks[i] == check)
529 break;
531 if (i >= check_vector.nr)
532 BUG("no entry found");
534 /* shift entries over */
535 for (; i < check_vector.nr - 1; i++)
536 check_vector.checks[i] = check_vector.checks[i + 1];
538 check_vector.nr--;
540 vector_unlock();
543 /* Iterate through all attr_check instances and drop their stacks */
544 static void drop_all_attr_stacks(void)
546 int i;
548 vector_lock();
550 for (i = 0; i < check_vector.nr; i++) {
551 drop_attr_stack(&check_vector.checks[i]->stack);
554 vector_unlock();
557 struct attr_check *attr_check_alloc(void)
559 struct attr_check *c = xcalloc(1, sizeof(struct attr_check));
561 /* save pointer to the check struct */
562 check_vector_add(c);
564 return c;
567 struct attr_check *attr_check_initl(const char *one, ...)
569 struct attr_check *check;
570 int cnt;
571 va_list params;
572 const char *param;
574 va_start(params, one);
575 for (cnt = 1; (param = va_arg(params, const char *)) != NULL; cnt++)
577 va_end(params);
579 check = attr_check_alloc();
580 check->nr = cnt;
581 check->alloc = cnt;
582 check->items = xcalloc(cnt, sizeof(struct attr_check_item));
584 check->items[0].attr = git_attr(one);
585 va_start(params, one);
586 for (cnt = 1; cnt < check->nr; cnt++) {
587 const struct git_attr *attr;
588 param = va_arg(params, const char *);
589 if (!param)
590 BUG("counted %d != ended at %d",
591 check->nr, cnt);
592 attr = git_attr(param);
593 if (!attr)
594 BUG("%s: not a valid attribute name", param);
595 check->items[cnt].attr = attr;
597 va_end(params);
598 return check;
601 struct attr_check *attr_check_dup(const struct attr_check *check)
603 struct attr_check *ret;
605 if (!check)
606 return NULL;
608 ret = attr_check_alloc();
610 ret->nr = check->nr;
611 ret->alloc = check->alloc;
612 ALLOC_ARRAY(ret->items, ret->nr);
613 COPY_ARRAY(ret->items, check->items, ret->nr);
615 return ret;
618 struct attr_check_item *attr_check_append(struct attr_check *check,
619 const struct git_attr *attr)
621 struct attr_check_item *item;
623 ALLOC_GROW(check->items, check->nr + 1, check->alloc);
624 item = &check->items[check->nr++];
625 item->attr = attr;
626 return item;
629 void attr_check_reset(struct attr_check *check)
631 check->nr = 0;
634 void attr_check_clear(struct attr_check *check)
636 FREE_AND_NULL(check->items);
637 check->alloc = 0;
638 check->nr = 0;
640 FREE_AND_NULL(check->all_attrs);
641 check->all_attrs_nr = 0;
643 drop_attr_stack(&check->stack);
646 void attr_check_free(struct attr_check *check)
648 if (check) {
649 /* Remove check from the check vector */
650 check_vector_remove(check);
652 attr_check_clear(check);
653 free(check);
657 static const char *builtin_attr[] = {
658 "[attr]binary -diff -merge -text",
659 NULL,
662 static void handle_attr_line(struct attr_stack *res,
663 const char *line,
664 const char *src,
665 int lineno,
666 int macro_ok)
668 struct match_attr *a;
670 a = parse_attr_line(line, src, lineno, macro_ok);
671 if (!a)
672 return;
673 ALLOC_GROW(res->attrs, res->num_matches + 1, res->alloc);
674 res->attrs[res->num_matches++] = a;
677 static struct attr_stack *read_attr_from_array(const char **list)
679 struct attr_stack *res;
680 const char *line;
681 int lineno = 0;
683 res = xcalloc(1, sizeof(*res));
684 while ((line = *(list++)) != NULL)
685 handle_attr_line(res, line, "[builtin]", ++lineno, 1);
686 return res;
690 * Callers into the attribute system assume there is a single, system-wide
691 * global state where attributes are read from and when the state is flipped by
692 * calling git_attr_set_direction(), the stack frames that have been
693 * constructed need to be discarded so so that subsequent calls into the
694 * attribute system will lazily read from the right place. Since changing
695 * direction causes a global paradigm shift, it should not ever be called while
696 * another thread could potentially be calling into the attribute system.
698 static enum git_attr_direction direction;
700 void git_attr_set_direction(enum git_attr_direction new_direction)
702 if (is_bare_repository() && new_direction != GIT_ATTR_INDEX)
703 BUG("non-INDEX attr direction in a bare repo");
705 if (new_direction != direction)
706 drop_all_attr_stacks();
708 direction = new_direction;
711 static struct attr_stack *read_attr_from_file(const char *path, int macro_ok)
713 FILE *fp = fopen_or_warn(path, "r");
714 struct attr_stack *res;
715 char buf[2048];
716 int lineno = 0;
718 if (!fp)
719 return NULL;
720 res = xcalloc(1, sizeof(*res));
721 while (fgets(buf, sizeof(buf), fp)) {
722 char *bufp = buf;
723 if (!lineno)
724 skip_utf8_bom(&bufp, strlen(bufp));
725 handle_attr_line(res, bufp, path, ++lineno, macro_ok);
727 fclose(fp);
728 return res;
731 static struct attr_stack *read_attr_from_index(const struct index_state *istate,
732 const char *path,
733 int macro_ok)
735 struct attr_stack *res;
736 char *buf, *sp;
737 int lineno = 0;
739 if (!istate)
740 return NULL;
742 buf = read_blob_data_from_index(istate, path, NULL);
743 if (!buf)
744 return NULL;
746 res = xcalloc(1, sizeof(*res));
747 for (sp = buf; *sp; ) {
748 char *ep;
749 int more;
751 ep = strchrnul(sp, '\n');
752 more = (*ep == '\n');
753 *ep = '\0';
754 handle_attr_line(res, sp, path, ++lineno, macro_ok);
755 sp = ep + more;
757 free(buf);
758 return res;
761 static struct attr_stack *read_attr(const struct index_state *istate,
762 const char *path, int macro_ok)
764 struct attr_stack *res = NULL;
766 if (direction == GIT_ATTR_INDEX) {
767 res = read_attr_from_index(istate, path, macro_ok);
768 } else if (!is_bare_repository()) {
769 if (direction == GIT_ATTR_CHECKOUT) {
770 res = read_attr_from_index(istate, path, macro_ok);
771 if (!res)
772 res = read_attr_from_file(path, macro_ok);
773 } else if (direction == GIT_ATTR_CHECKIN) {
774 res = read_attr_from_file(path, macro_ok);
775 if (!res)
777 * There is no checked out .gitattributes file
778 * there, but we might have it in the index.
779 * We allow operation in a sparsely checked out
780 * work tree, so read from it.
782 res = read_attr_from_index(istate, path, macro_ok);
786 if (!res)
787 res = xcalloc(1, sizeof(*res));
788 return res;
791 #if DEBUG_ATTR
792 static void debug_info(const char *what, struct attr_stack *elem)
794 fprintf(stderr, "%s: %s\n", what, elem->origin ? elem->origin : "()");
796 static void debug_set(const char *what, const char *match, struct git_attr *attr, const void *v)
798 const char *value = v;
800 if (ATTR_TRUE(value))
801 value = "set";
802 else if (ATTR_FALSE(value))
803 value = "unset";
804 else if (ATTR_UNSET(value))
805 value = "unspecified";
807 fprintf(stderr, "%s: %s => %s (%s)\n",
808 what, attr->name, (char *) value, match);
810 #define debug_push(a) debug_info("push", (a))
811 #define debug_pop(a) debug_info("pop", (a))
812 #else
813 #define debug_push(a) do { ; } while (0)
814 #define debug_pop(a) do { ; } while (0)
815 #define debug_set(a,b,c,d) do { ; } while (0)
816 #endif /* DEBUG_ATTR */
818 static const char *git_etc_gitattributes(void)
820 static const char *system_wide;
821 if (!system_wide)
822 system_wide = system_path(ETC_GITATTRIBUTES);
823 return system_wide;
826 static const char *get_home_gitattributes(void)
828 if (!git_attributes_file)
829 git_attributes_file = xdg_config_home("attributes");
831 return git_attributes_file;
834 static int git_attr_system(void)
836 return !git_env_bool("GIT_ATTR_NOSYSTEM", 0);
839 static GIT_PATH_FUNC(git_path_info_attributes, INFOATTRIBUTES_FILE)
841 static void push_stack(struct attr_stack **attr_stack_p,
842 struct attr_stack *elem, char *origin, size_t originlen)
844 if (elem) {
845 elem->origin = origin;
846 if (origin)
847 elem->originlen = originlen;
848 elem->prev = *attr_stack_p;
849 *attr_stack_p = elem;
853 static void bootstrap_attr_stack(const struct index_state *istate,
854 struct attr_stack **stack)
856 struct attr_stack *e;
858 if (*stack)
859 return;
861 /* builtin frame */
862 e = read_attr_from_array(builtin_attr);
863 push_stack(stack, e, NULL, 0);
865 /* system-wide frame */
866 if (git_attr_system()) {
867 e = read_attr_from_file(git_etc_gitattributes(), 1);
868 push_stack(stack, e, NULL, 0);
871 /* home directory */
872 if (get_home_gitattributes()) {
873 e = read_attr_from_file(get_home_gitattributes(), 1);
874 push_stack(stack, e, NULL, 0);
877 /* root directory */
878 e = read_attr(istate, GITATTRIBUTES_FILE, 1);
879 push_stack(stack, e, xstrdup(""), 0);
881 /* info frame */
882 if (startup_info->have_repository)
883 e = read_attr_from_file(git_path_info_attributes(), 1);
884 else
885 e = NULL;
886 if (!e)
887 e = xcalloc(1, sizeof(struct attr_stack));
888 push_stack(stack, e, NULL, 0);
891 static void prepare_attr_stack(const struct index_state *istate,
892 const char *path, int dirlen,
893 struct attr_stack **stack)
895 struct attr_stack *info;
896 struct strbuf pathbuf = STRBUF_INIT;
899 * At the bottom of the attribute stack is the built-in
900 * set of attribute definitions, followed by the contents
901 * of $(prefix)/etc/gitattributes and a file specified by
902 * core.attributesfile. Then, contents from
903 * .gitattribute files from directories closer to the
904 * root to the ones in deeper directories are pushed
905 * to the stack. Finally, at the very top of the stack
906 * we always keep the contents of $GIT_DIR/info/attributes.
908 * When checking, we use entries from near the top of the
909 * stack, preferring $GIT_DIR/info/attributes, then
910 * .gitattributes in deeper directories to shallower ones,
911 * and finally use the built-in set as the default.
913 bootstrap_attr_stack(istate, stack);
916 * Pop the "info" one that is always at the top of the stack.
918 info = *stack;
919 *stack = info->prev;
922 * Pop the ones from directories that are not the prefix of
923 * the path we are checking. Break out of the loop when we see
924 * the root one (whose origin is an empty string "") or the builtin
925 * one (whose origin is NULL) without popping it.
927 while ((*stack)->origin) {
928 int namelen = (*stack)->originlen;
929 struct attr_stack *elem;
931 elem = *stack;
932 if (namelen <= dirlen &&
933 !strncmp(elem->origin, path, namelen) &&
934 (!namelen || path[namelen] == '/'))
935 break;
937 debug_pop(elem);
938 *stack = elem->prev;
939 attr_stack_free(elem);
943 * bootstrap_attr_stack() should have added, and the
944 * above loop should have stopped before popping, the
945 * root element whose attr_stack->origin is set to an
946 * empty string.
948 assert((*stack)->origin);
950 strbuf_addstr(&pathbuf, (*stack)->origin);
951 /* Build up to the directory 'path' is in */
952 while (pathbuf.len < dirlen) {
953 size_t len = pathbuf.len;
954 struct attr_stack *next;
955 char *origin;
957 /* Skip path-separator */
958 if (len < dirlen && is_dir_sep(path[len]))
959 len++;
960 /* Find the end of the next component */
961 while (len < dirlen && !is_dir_sep(path[len]))
962 len++;
964 if (pathbuf.len > 0)
965 strbuf_addch(&pathbuf, '/');
966 strbuf_add(&pathbuf, path + pathbuf.len, (len - pathbuf.len));
967 strbuf_addf(&pathbuf, "/%s", GITATTRIBUTES_FILE);
969 next = read_attr(istate, pathbuf.buf, 0);
971 /* reset the pathbuf to not include "/.gitattributes" */
972 strbuf_setlen(&pathbuf, len);
974 origin = xstrdup(pathbuf.buf);
975 push_stack(stack, next, origin, len);
979 * Finally push the "info" one at the top of the stack.
981 push_stack(stack, info, NULL, 0);
983 strbuf_release(&pathbuf);
986 static int path_matches(const char *pathname, int pathlen,
987 int basename_offset,
988 const struct pattern *pat,
989 const char *base, int baselen)
991 const char *pattern = pat->pattern;
992 int prefix = pat->nowildcardlen;
993 int isdir = (pathlen && pathname[pathlen - 1] == '/');
995 if ((pat->flags & EXC_FLAG_MUSTBEDIR) && !isdir)
996 return 0;
998 if (pat->flags & EXC_FLAG_NODIR) {
999 return match_basename(pathname + basename_offset,
1000 pathlen - basename_offset - isdir,
1001 pattern, prefix,
1002 pat->patternlen, pat->flags);
1004 return match_pathname(pathname, pathlen - isdir,
1005 base, baselen,
1006 pattern, prefix, pat->patternlen, pat->flags);
1009 static int macroexpand_one(struct all_attrs_item *all_attrs, int nr, int rem);
1011 static int fill_one(const char *what, struct all_attrs_item *all_attrs,
1012 const struct match_attr *a, int rem)
1014 int i;
1016 for (i = a->num_attr - 1; rem > 0 && i >= 0; i--) {
1017 const struct git_attr *attr = a->state[i].attr;
1018 const char **n = &(all_attrs[attr->attr_nr].value);
1019 const char *v = a->state[i].setto;
1021 if (*n == ATTR__UNKNOWN) {
1022 debug_set(what,
1023 a->is_macro ? a->u.attr->name : a->u.pat.pattern,
1024 attr, v);
1025 *n = v;
1026 rem--;
1027 rem = macroexpand_one(all_attrs, attr->attr_nr, rem);
1030 return rem;
1033 static int fill(const char *path, int pathlen, int basename_offset,
1034 const struct attr_stack *stack,
1035 struct all_attrs_item *all_attrs, int rem)
1037 for (; rem > 0 && stack; stack = stack->prev) {
1038 int i;
1039 const char *base = stack->origin ? stack->origin : "";
1041 for (i = stack->num_matches - 1; 0 < rem && 0 <= i; i--) {
1042 const struct match_attr *a = stack->attrs[i];
1043 if (a->is_macro)
1044 continue;
1045 if (path_matches(path, pathlen, basename_offset,
1046 &a->u.pat, base, stack->originlen))
1047 rem = fill_one("fill", all_attrs, a, rem);
1051 return rem;
1054 static int macroexpand_one(struct all_attrs_item *all_attrs, int nr, int rem)
1056 const struct all_attrs_item *item = &all_attrs[nr];
1058 if (item->macro && item->value == ATTR__TRUE)
1059 return fill_one("expand", all_attrs, item->macro, rem);
1060 else
1061 return rem;
1065 * Marks the attributes which are macros based on the attribute stack.
1066 * This prevents having to search through the attribute stack each time
1067 * a macro needs to be expanded during the fill stage.
1069 static void determine_macros(struct all_attrs_item *all_attrs,
1070 const struct attr_stack *stack)
1072 for (; stack; stack = stack->prev) {
1073 int i;
1074 for (i = stack->num_matches - 1; i >= 0; i--) {
1075 const struct match_attr *ma = stack->attrs[i];
1076 if (ma->is_macro) {
1077 int n = ma->u.attr->attr_nr;
1078 if (!all_attrs[n].macro) {
1079 all_attrs[n].macro = ma;
1087 * Collect attributes for path into the array pointed to by check->all_attrs.
1088 * If check->check_nr is non-zero, only attributes in check[] are collected.
1089 * Otherwise all attributes are collected.
1091 static void collect_some_attrs(const struct index_state *istate,
1092 const char *path,
1093 struct attr_check *check)
1095 int i, pathlen, rem, dirlen;
1096 const char *cp, *last_slash = NULL;
1097 int basename_offset;
1099 for (cp = path; *cp; cp++) {
1100 if (*cp == '/' && cp[1])
1101 last_slash = cp;
1103 pathlen = cp - path;
1104 if (last_slash) {
1105 basename_offset = last_slash + 1 - path;
1106 dirlen = last_slash - path;
1107 } else {
1108 basename_offset = 0;
1109 dirlen = 0;
1112 prepare_attr_stack(istate, path, dirlen, &check->stack);
1113 all_attrs_init(&g_attr_hashmap, check);
1114 determine_macros(check->all_attrs, check->stack);
1116 if (check->nr) {
1117 rem = 0;
1118 for (i = 0; i < check->nr; i++) {
1119 int n = check->items[i].attr->attr_nr;
1120 struct all_attrs_item *item = &check->all_attrs[n];
1121 if (item->macro) {
1122 item->value = ATTR__UNSET;
1123 rem++;
1126 if (rem == check->nr)
1127 return;
1130 rem = check->all_attrs_nr;
1131 fill(path, pathlen, basename_offset, check->stack, check->all_attrs, rem);
1134 void git_check_attr(const struct index_state *istate,
1135 const char *path,
1136 struct attr_check *check)
1138 int i;
1140 collect_some_attrs(istate, path, check);
1142 for (i = 0; i < check->nr; i++) {
1143 size_t n = check->items[i].attr->attr_nr;
1144 const char *value = check->all_attrs[n].value;
1145 if (value == ATTR__UNKNOWN)
1146 value = ATTR__UNSET;
1147 check->items[i].value = value;
1151 void git_all_attrs(const struct index_state *istate,
1152 const char *path, struct attr_check *check)
1154 int i;
1156 attr_check_reset(check);
1157 collect_some_attrs(istate, path, check);
1159 for (i = 0; i < check->all_attrs_nr; i++) {
1160 const char *name = check->all_attrs[i].attr->name;
1161 const char *value = check->all_attrs[i].value;
1162 struct attr_check_item *item;
1163 if (value == ATTR__UNSET || value == ATTR__UNKNOWN)
1164 continue;
1165 item = attr_check_append(check, git_attr(name));
1166 item->value = value;
1170 void attr_start(void)
1172 pthread_mutex_init(&g_attr_hashmap.mutex, NULL);
1173 pthread_mutex_init(&check_vector.mutex, NULL);