attr: tighten const correctness with git_attr and match_attr
[git/git.git] / attr.c
CommitLineData
86ab7f0c
MH
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.
5 *
6 * One basic design decision here is that we are not going to support
7 * an insanely large number of attributes.
8 */
9
06f33c17 10#define NO_THE_INDEX_COMPATIBILITY_MACROS
d0bfd026 11#include "cache.h"
6df42ab9 12#include "exec_cmd.h"
d0bfd026 13#include "attr.h"
6eba6210 14#include "dir.h"
27547e5f 15#include "utf8.h"
860a74d9 16#include "quote.h"
1a600b75 17#include "thread-utils.h"
d0bfd026 18
a5e92abd
JH
19const char git_attr__true[] = "(builtin)true";
20const char git_attr__false[] = "\0(builtin)false";
21static const char git_attr__unknown[] = "(builtin)unknown";
22#define ATTR__TRUE git_attr__true
23#define ATTR__FALSE git_attr__false
24#define ATTR__UNSET NULL
25#define ATTR__UNKNOWN git_attr__unknown
515106fa 26
d0bfd026
JH
27#ifndef DEBUG_ATTR
28#define DEBUG_ATTR 0
29#endif
30
31struct git_attr {
1a600b75 32 int attr_nr; /* unique attribute number */
1a600b75 33 char name[FLEX_ARRAY]; /* attribute name */
d0bfd026 34};
7d42ec54 35
ec4d77aa 36const char *git_attr_name(const struct git_attr *attr)
352404ac
MH
37{
38 return attr->name;
39}
40
1a600b75
BW
41struct attr_hashmap {
42 struct hashmap map;
43#ifndef NO_PTHREADS
44 pthread_mutex_t mutex;
45#endif
46};
47
48static inline void hashmap_lock(struct attr_hashmap *map)
49{
50#ifndef NO_PTHREADS
51 pthread_mutex_lock(&map->mutex);
52#endif
53}
54
55static inline void hashmap_unlock(struct attr_hashmap *map)
d0bfd026 56{
1a600b75
BW
57#ifndef NO_PTHREADS
58 pthread_mutex_unlock(&map->mutex);
59#endif
60}
d0bfd026 61
1a600b75
BW
62/*
63 * The global dictionary of all interned attributes. This
64 * is a singleton object which is shared between threads.
65 * Access to this dictionary must be surrounded with a mutex.
66 */
67static struct attr_hashmap g_attr_hashmap;
68
69/* The container for objects stored in "struct attr_hashmap" */
70struct attr_hash_entry {
71 struct hashmap_entry ent; /* must be the first member! */
72 const char *key; /* the key; memory should be owned by value */
73 size_t keylen; /* length of the key */
74 void *value; /* the stored value */
75};
76
77/* attr_hashmap comparison function */
78static int attr_hash_entry_cmp(const struct attr_hash_entry *a,
79 const struct attr_hash_entry *b,
80 void *unused)
81{
82 return (a->keylen != b->keylen) || strncmp(a->key, b->key, a->keylen);
83}
84
85/* Initialize an 'attr_hashmap' object */
86static void attr_hashmap_init(struct attr_hashmap *map)
87{
88 hashmap_init(&map->map, (hashmap_cmp_fn) attr_hash_entry_cmp, 0);
89}
90
91/*
92 * Retrieve the 'value' stored in a hashmap given the provided 'key'.
93 * If there is no matching entry, return NULL.
94 */
95static void *attr_hashmap_get(struct attr_hashmap *map,
96 const char *key, size_t keylen)
97{
98 struct attr_hash_entry k;
99 struct attr_hash_entry *e;
100
101 if (!map->map.tablesize)
102 attr_hashmap_init(map);
103
104 hashmap_entry_init(&k, memhash(key, keylen));
105 k.key = key;
106 k.keylen = keylen;
107 e = hashmap_get(&map->map, &k, NULL);
108
109 return e ? e->value : NULL;
110}
111
112/* Add 'value' to a hashmap based on the provided 'key'. */
113static void attr_hashmap_add(struct attr_hashmap *map,
114 const char *key, size_t keylen,
115 void *value)
116{
117 struct attr_hash_entry *e;
118
119 if (!map->map.tablesize)
120 attr_hashmap_init(map);
121
122 e = xmalloc(sizeof(struct attr_hash_entry));
123 hashmap_entry_init(e, memhash(key, keylen));
124 e->key = key;
125 e->keylen = keylen;
126 e->value = value;
127
128 hashmap_add(&map->map, e);
d0bfd026
JH
129}
130
685b2925
BW
131struct all_attrs_item {
132 const struct git_attr *attr;
133 const char *value;
60a12722
BW
134 /*
135 * If 'macro' is non-NULL, indicates that 'attr' is a macro based on
136 * the current attribute stack and contains a pointer to the match_attr
137 * definition of the macro
138 */
139 const struct match_attr *macro;
685b2925
BW
140};
141
142/*
143 * Reallocate and reinitialize the array of all attributes (which is used in
144 * the attribute collection process) in 'check' based on the global dictionary
145 * of attributes.
146 */
147static void all_attrs_init(struct attr_hashmap *map, struct attr_check *check)
148{
149 int i;
150
151 hashmap_lock(map);
152
153 if (map->map.size < check->all_attrs_nr)
154 die("BUG: interned attributes shouldn't be deleted");
155
156 /*
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.
161 */
162 if (map->map.size != check->all_attrs_nr) {
163 struct attr_hash_entry *e;
164 struct hashmap_iter iter;
165 hashmap_iter_init(&map->map, &iter);
166
167 REALLOC_ARRAY(check->all_attrs, map->map.size);
168 check->all_attrs_nr = map->map.size;
169
170 while ((e = hashmap_iter_next(&iter))) {
171 const struct git_attr *a = e->value;
172 check->all_attrs[a->attr_nr].attr = a;
173 }
174 }
175
176 hashmap_unlock(map);
177
178 /*
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.
182 */
183 for (i = 0; i < check->all_attrs_nr; i++) {
184 check->all_attrs[i].value = ATTR__UNKNOWN;
60a12722 185 check->all_attrs[i].macro = NULL;
685b2925
BW
186 }
187}
188
428103c7 189static int attr_name_valid(const char *name, size_t namelen)
e4aee10a
JH
190{
191 /*
d42453ab
MH
192 * Attribute name cannot begin with '-' and must consist of
193 * characters from [-A-Za-z0-9_.].
e4aee10a 194 */
c0b13b21 195 if (namelen <= 0 || *name == '-')
428103c7 196 return 0;
e4aee10a
JH
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')) )
428103c7 203 return 0;
e4aee10a 204 }
428103c7
JH
205 return 1;
206}
207
208static void report_invalid_attr(const char *name, size_t len,
209 const char *src, int lineno)
210{
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);
e4aee10a
JH
216}
217
1a600b75
BW
218/*
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.
222 */
e810e063 223static const struct git_attr *git_attr_internal(const char *name, int namelen)
d0bfd026 224{
d0bfd026
JH
225 struct git_attr *a;
226
1a600b75 227 if (!attr_name_valid(name, namelen))
e4aee10a
JH
228 return NULL;
229
1a600b75
BW
230 hashmap_lock(&g_attr_hashmap);
231
232 a = attr_hashmap_get(&g_attr_hashmap, name, namelen);
233
234 if (!a) {
235 FLEX_ALLOC_MEM(a, name, name, namelen);
236 a->attr_nr = g_attr_hashmap.map.size;
1a600b75
BW
237
238 attr_hashmap_add(&g_attr_hashmap, a->name, namelen, a);
239 assert(a->attr_nr == (g_attr_hashmap.map.size - 1));
1a600b75
BW
240 }
241
242 hashmap_unlock(&g_attr_hashmap);
f48fd688 243
d0bfd026
JH
244 return a;
245}
246
e810e063 247const struct git_attr *git_attr(const char *name)
7fb0eaa2
JH
248{
249 return git_attr_internal(name, strlen(name));
250}
251
515106fa 252/* What does a matched pattern decide? */
d0bfd026 253struct attr_state {
e810e063 254 const struct git_attr *attr;
a5e92abd 255 const char *setto;
d0bfd026
JH
256};
257
82dce998
NTND
258struct pattern {
259 const char *pattern;
260 int patternlen;
261 int nowildcardlen;
f8708998 262 unsigned flags; /* EXC_FLAG_* */
82dce998
NTND
263};
264
ba845b75
MH
265/*
266 * One rule, as from a .gitattributes file.
267 *
268 * If is_macro is true, then u.attr is a pointer to the git_attr being
269 * defined.
270 *
4894f4ff
JH
271 * If is_macro is false, then u.pat is the filename pattern to which the
272 * rule applies.
ba845b75
MH
273 *
274 * In either case, num_attr is the number of attributes affected by
275 * this rule, and state is an array listing them. The attributes are
276 * listed as they appear in the file (macros unexpanded).
277 */
d0bfd026 278struct match_attr {
f48fd688 279 union {
82dce998 280 struct pattern pat;
e810e063 281 const struct git_attr *attr;
f48fd688
JH
282 } u;
283 char is_macro;
d0bfd026
JH
284 unsigned num_attr;
285 struct attr_state state[FLEX_ARRAY];
286};
287
288static const char blank[] = " \t\r\n";
289
d1751298
MH
290/*
291 * Parse a whitespace-delimited attribute state (i.e., "attr",
292 * "-attr", "!attr", or "attr=value") from the string starting at src.
293 * If e is not NULL, write the results to *e. Return a pointer to the
294 * remainder of the string (with leading whitespace removed), or NULL
295 * if there was an error.
296 */
515106fa 297static const char *parse_attr(const char *src, int lineno, const char *cp,
d1751298 298 struct attr_state *e)
515106fa
JH
299{
300 const char *ep, *equals;
301 int len;
302
303 ep = cp + strcspn(cp, blank);
304 equals = strchr(cp, '=');
305 if (equals && ep < equals)
306 equals = NULL;
307 if (equals)
308 len = equals - cp;
309 else
310 len = ep - cp;
d1751298 311 if (!e) {
515106fa
JH
312 if (*cp == '-' || *cp == '!') {
313 cp++;
314 len--;
315 }
428103c7
JH
316 if (!attr_name_valid(cp, len)) {
317 report_invalid_attr(cp, len, src, lineno);
515106fa
JH
318 return NULL;
319 }
320 } else {
5a884019
JH
321 /*
322 * As this function is always called twice, once with
323 * e == NULL in the first pass and then e != NULL in
428103c7 324 * the second pass, no need for attr_name_valid()
5a884019
JH
325 * check here.
326 */
515106fa
JH
327 if (*cp == '-' || *cp == '!') {
328 e->setto = (*cp == '-') ? ATTR__FALSE : ATTR__UNSET;
329 cp++;
330 len--;
331 }
332 else if (!equals)
333 e->setto = ATTR__TRUE;
334 else {
182af834 335 e->setto = xmemdupz(equals + 1, ep - equals - 1);
515106fa 336 }
7fb0eaa2 337 e->attr = git_attr_internal(cp, len);
515106fa 338 }
515106fa
JH
339 return ep + strspn(ep, blank);
340}
341
f48fd688
JH
342static struct match_attr *parse_attr_line(const char *line, const char *src,
343 int lineno, int macro_ok)
d0bfd026
JH
344{
345 int namelen;
d68e1c18 346 int num_attr, i;
85c4a0d0 347 const char *cp, *name, *states;
515106fa 348 struct match_attr *res = NULL;
f48fd688 349 int is_macro;
860a74d9 350 struct strbuf pattern = STRBUF_INIT;
d0bfd026
JH
351
352 cp = line + strspn(line, blank);
353 if (!*cp || *cp == '#')
354 return NULL;
355 name = cp;
860a74d9
NTND
356
357 if (*cp == '"' && !unquote_c_style(&pattern, name, &states)) {
358 name = pattern.buf;
359 namelen = pattern.len;
360 } else {
361 namelen = strcspn(name, blank);
362 states = name + namelen;
363 }
364
f48fd688 365 if (strlen(ATTRIBUTE_MACRO_PREFIX) < namelen &&
59556548 366 starts_with(name, ATTRIBUTE_MACRO_PREFIX)) {
f48fd688
JH
367 if (!macro_ok) {
368 fprintf(stderr, "%s not allowed: %s:%d\n",
369 name, src, lineno);
62af8969 370 goto fail_return;
f48fd688
JH
371 }
372 is_macro = 1;
373 name += strlen(ATTRIBUTE_MACRO_PREFIX);
374 name += strspn(name, blank);
375 namelen = strcspn(name, blank);
428103c7
JH
376 if (!attr_name_valid(name, namelen)) {
377 report_invalid_attr(name, namelen, src, lineno);
62af8969 378 goto fail_return;
e4aee10a 379 }
f48fd688
JH
380 }
381 else
382 is_macro = 0;
d0bfd026 383
85c4a0d0
MH
384 states += strspn(states, blank);
385
d68e1c18
MH
386 /* First pass to count the attr_states */
387 for (cp = states, num_attr = 0; *cp; num_attr++) {
388 cp = parse_attr(src, lineno, cp, NULL);
389 if (!cp)
62af8969 390 goto fail_return;
d0bfd026 391 }
d68e1c18
MH
392
393 res = xcalloc(1,
394 sizeof(*res) +
395 sizeof(struct attr_state) * num_attr +
396 (is_macro ? 0 : namelen + 1));
fad32bcd 397 if (is_macro) {
d68e1c18 398 res->u.attr = git_attr_internal(name, namelen);
fad32bcd 399 } else {
82dce998
NTND
400 char *p = (char *)&(res->state[num_attr]);
401 memcpy(p, name, namelen);
402 res->u.pat.pattern = p;
403 parse_exclude_pattern(&res->u.pat.pattern,
404 &res->u.pat.patternlen,
405 &res->u.pat.flags,
406 &res->u.pat.nowildcardlen);
8b1bd024
TR
407 if (res->u.pat.flags & EXC_FLAG_NEGATIVE) {
408 warning(_("Negative patterns are ignored in git attributes\n"
409 "Use '\\!' for literal leading exclamation."));
62af8969 410 goto fail_return;
8b1bd024 411 }
d0bfd026 412 }
d68e1c18
MH
413 res->is_macro = is_macro;
414 res->num_attr = num_attr;
415
416 /* Second pass to fill the attr_states */
417 for (cp = states, i = 0; *cp; i++) {
418 cp = parse_attr(src, lineno, cp, &(res->state[i]));
419 }
420
860a74d9 421 strbuf_release(&pattern);
d0bfd026 422 return res;
62af8969
JH
423
424fail_return:
860a74d9 425 strbuf_release(&pattern);
62af8969
JH
426 free(res);
427 return NULL;
d0bfd026
JH
428}
429
430/*
431 * Like info/exclude and .gitignore, the attribute information can
432 * come from many places.
433 *
434 * (1) .gitattribute file of the same directory;
515106fa
JH
435 * (2) .gitattribute file of the parent directory if (1) does not have
436 * any match; this goes recursively upwards, just like .gitignore.
437 * (3) $GIT_DIR/info/attributes, which overrides both of the above.
d0bfd026
JH
438 *
439 * In the same file, later entries override the earlier match, so in the
440 * global list, we would have entries from info/attributes the earliest
441 * (reading the file from top to bottom), .gitattribute of the root
442 * directory (again, reading the file from top to bottom) down to the
443 * current directory, and then scan the list backwards to find the first match.
6d24e7a8 444 * This is exactly the same as what is_excluded() does in dir.c to deal with
6f416cba 445 * .gitignore file and info/excludes file as a fallback.
d0bfd026
JH
446 */
447
7d42ec54 448/* NEEDSWORK: This will become per git_attr_check */
d0bfd026
JH
449static struct attr_stack {
450 struct attr_stack *prev;
451 char *origin;
cd6a0b26 452 size_t originlen;
d0bfd026 453 unsigned num_matches;
a4413118 454 unsigned alloc;
d0bfd026
JH
455 struct match_attr **attrs;
456} *attr_stack;
457
458static void free_attr_elem(struct attr_stack *e)
459{
460 int i;
461 free(e->origin);
515106fa
JH
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++) {
a5e92abd 466 const char *setto = a->state[j].setto;
515106fa
JH
467 if (setto == ATTR__TRUE ||
468 setto == ATTR__FALSE ||
469 setto == ATTR__UNSET ||
470 setto == ATTR__UNKNOWN)
471 ;
472 else
4b25d091 473 free((char *) setto);
515106fa
JH
474 }
475 free(a);
476 }
37475f97 477 free(e->attrs);
d0bfd026
JH
478 free(e);
479}
480
37293768
JH
481struct attr_check *attr_check_alloc(void)
482{
483 return xcalloc(1, sizeof(struct attr_check));
484}
485
486struct attr_check *attr_check_initl(const char *one, ...)
487{
488 struct attr_check *check;
489 int cnt;
490 va_list params;
491 const char *param;
492
493 va_start(params, one);
494 for (cnt = 1; (param = va_arg(params, const char *)) != NULL; cnt++)
495 ;
496 va_end(params);
497
498 check = attr_check_alloc();
499 check->nr = cnt;
500 check->alloc = cnt;
501 check->items = xcalloc(cnt, sizeof(struct attr_check_item));
502
503 check->items[0].attr = git_attr(one);
504 va_start(params, one);
505 for (cnt = 1; cnt < check->nr; cnt++) {
506 const struct git_attr *attr;
507 param = va_arg(params, const char *);
508 if (!param)
509 die("BUG: counted %d != ended at %d",
510 check->nr, cnt);
511 attr = git_attr(param);
512 if (!attr)
513 die("BUG: %s: not a valid attribute name", param);
514 check->items[cnt].attr = attr;
515 }
516 va_end(params);
517 return check;
518}
519
520struct attr_check_item *attr_check_append(struct attr_check *check,
521 const struct git_attr *attr)
522{
523 struct attr_check_item *item;
524
525 ALLOC_GROW(check->items, check->nr + 1, check->alloc);
526 item = &check->items[check->nr++];
527 item->attr = attr;
528 return item;
529}
530
531void attr_check_reset(struct attr_check *check)
532{
533 check->nr = 0;
534}
535
536void attr_check_clear(struct attr_check *check)
537{
538 free(check->items);
539 check->items = NULL;
540 check->alloc = 0;
541 check->nr = 0;
685b2925
BW
542
543 free(check->all_attrs);
544 check->all_attrs = NULL;
545 check->all_attrs_nr = 0;
37293768
JH
546}
547
548void attr_check_free(struct attr_check *check)
549{
550 attr_check_clear(check);
551 free(check);
552}
553
d0bfd026 554static const char *builtin_attr[] = {
155a4b71 555 "[attr]binary -diff -merge -text",
d0bfd026
JH
556 NULL,
557};
558
a4413118
JH
559static void handle_attr_line(struct attr_stack *res,
560 const char *line,
561 const char *src,
562 int lineno,
563 int macro_ok)
564{
565 struct match_attr *a;
566
567 a = parse_attr_line(line, src, lineno, macro_ok);
568 if (!a)
569 return;
3a7fa03d 570 ALLOC_GROW(res->attrs, res->num_matches + 1, res->alloc);
a4413118
JH
571 res->attrs[res->num_matches++] = a;
572}
573
d0bfd026
JH
574static struct attr_stack *read_attr_from_array(const char **list)
575{
576 struct attr_stack *res;
577 const char *line;
f48fd688 578 int lineno = 0;
d0bfd026
JH
579
580 res = xcalloc(1, sizeof(*res));
a4413118
JH
581 while ((line = *(list++)) != NULL)
582 handle_attr_line(res, line, "[builtin]", ++lineno, 1);
d0bfd026
JH
583 return res;
584}
585
7d42ec54
JH
586/*
587 * NEEDSWORK: these two are tricky. The callers assume there is a
588 * single, system-wide global state "where we read attributes from?"
589 * and when the state is flipped by calling git_attr_set_direction(),
590 * attr_stack is discarded so that subsequent attr_check will lazily
591 * read from the right place. And they do not know or care who called
592 * by them uses the attribute subsystem, hence have no knowledge of
593 * existing git_attr_check instances or future ones that will be
594 * created).
595 *
596 * Probably we need a thread_local that holds these two variables,
597 * and a list of git_attr_check instances (which need to be maintained
598 * by hooking into git_attr_check_alloc(), git_attr_check_initl(), and
599 * git_attr_check_clear(). Then git_attr_set_direction() updates the
600 * fields in that thread_local for these two variables, iterate over
601 * all the active git_attr_check instances and discard the attr_stack
602 * they hold. Yuck, but it sounds doable.
603 */
06f33c17
JH
604static enum git_attr_direction direction;
605static struct index_state *use_index;
606
f48fd688 607static struct attr_stack *read_attr_from_file(const char *path, int macro_ok)
d0bfd026 608{
a4413118 609 FILE *fp = fopen(path, "r");
d0bfd026
JH
610 struct attr_stack *res;
611 char buf[2048];
f48fd688 612 int lineno = 0;
d0bfd026 613
11e50b27 614 if (!fp) {
8e950dab 615 if (errno != ENOENT && errno != ENOTDIR)
55b38a48 616 warn_on_inaccessible(path);
a4413118 617 return NULL;
11e50b27 618 }
a4413118 619 res = xcalloc(1, sizeof(*res));
27547e5f
JH
620 while (fgets(buf, sizeof(buf), fp)) {
621 char *bufp = buf;
622 if (!lineno)
623 skip_utf8_bom(&bufp, strlen(bufp));
624 handle_attr_line(res, bufp, path, ++lineno, macro_ok);
625 }
a4413118
JH
626 fclose(fp);
627 return res;
628}
d0bfd026 629
06f33c17 630static struct attr_stack *read_attr_from_index(const char *path, int macro_ok)
a4413118
JH
631{
632 struct attr_stack *res;
1a9d7e9b
JH
633 char *buf, *sp;
634 int lineno = 0;
f48fd688 635
ff366825 636 buf = read_blob_data_from_index(use_index ? use_index : &the_index, path, NULL);
1a9d7e9b 637 if (!buf)
06f33c17 638 return NULL;
1a9d7e9b 639
06f33c17 640 res = xcalloc(1, sizeof(*res));
1a9d7e9b
JH
641 for (sp = buf; *sp; ) {
642 char *ep;
643 int more;
263434f2
JH
644
645 ep = strchrnul(sp, '\n');
1a9d7e9b
JH
646 more = (*ep == '\n');
647 *ep = '\0';
648 handle_attr_line(res, sp, path, ++lineno, macro_ok);
649 sp = ep + more;
650 }
651 free(buf);
d0bfd026
JH
652 return res;
653}
654
06f33c17
JH
655static struct attr_stack *read_attr(const char *path, int macro_ok)
656{
657 struct attr_stack *res;
658
659 if (direction == GIT_ATTR_CHECKOUT) {
660 res = read_attr_from_index(path, macro_ok);
661 if (!res)
662 res = read_attr_from_file(path, macro_ok);
663 }
4191e80a 664 else if (direction == GIT_ATTR_CHECKIN) {
06f33c17
JH
665 res = read_attr_from_file(path, macro_ok);
666 if (!res)
667 /*
668 * There is no checked out .gitattributes file there, but
669 * we might have it in the index. We allow operation in a
670 * sparsely checked out work tree, so read from it.
671 */
672 res = read_attr_from_index(path, macro_ok);
673 }
4191e80a
NTND
674 else
675 res = read_attr_from_index(path, macro_ok);
06f33c17
JH
676 if (!res)
677 res = xcalloc(1, sizeof(*res));
678 return res;
679}
680
d0bfd026
JH
681#if DEBUG_ATTR
682static void debug_info(const char *what, struct attr_stack *elem)
683{
684 fprintf(stderr, "%s: %s\n", what, elem->origin ? elem->origin : "()");
685}
cf94ccda 686static void debug_set(const char *what, const char *match, struct git_attr *attr, const void *v)
f48fd688 687{
515106fa
JH
688 const char *value = v;
689
690 if (ATTR_TRUE(value))
691 value = "set";
692 else if (ATTR_FALSE(value))
693 value = "unset";
694 else if (ATTR_UNSET(value))
695 value = "unspecified";
696
697 fprintf(stderr, "%s: %s => %s (%s)\n",
698 what, attr->name, (char *) value, match);
f48fd688 699}
d0bfd026
JH
700#define debug_push(a) debug_info("push", (a))
701#define debug_pop(a) debug_info("pop", (a))
702#else
703#define debug_push(a) do { ; } while (0)
704#define debug_pop(a) do { ; } while (0)
f48fd688 705#define debug_set(a,b,c,d) do { ; } while (0)
034d35c9 706#endif /* DEBUG_ATTR */
d0bfd026 707
06f33c17
JH
708static void drop_attr_stack(void)
709{
710 while (attr_stack) {
711 struct attr_stack *elem = attr_stack;
712 attr_stack = elem->prev;
713 free_attr_elem(elem);
714 }
715}
716
c5147722 717static const char *git_etc_gitattributes(void)
6df42ab9
PO
718{
719 static const char *system_wide;
720 if (!system_wide)
721 system_wide = system_path(ETC_GITATTRIBUTES);
722 return system_wide;
723}
724
c5147722 725static int git_attr_system(void)
6df42ab9
PO
726{
727 return !git_env_bool("GIT_ATTR_NOSYSTEM", 0);
728}
729
f932729c
JK
730static GIT_PATH_FUNC(git_path_info_attributes, INFOATTRIBUTES_FILE)
731
4c0ce074
JH
732static void push_stack(struct attr_stack **attr_stack_p,
733 struct attr_stack *elem, char *origin, size_t originlen)
734{
735 if (elem) {
736 elem->origin = origin;
737 if (origin)
738 elem->originlen = originlen;
739 elem->prev = *attr_stack_p;
740 *attr_stack_p = elem;
741 }
742}
743
f48fd688
JH
744static void bootstrap_attr_stack(void)
745{
909ca7b9 746 struct attr_stack *elem;
f48fd688 747
909ca7b9
JH
748 if (attr_stack)
749 return;
f48fd688 750
4c0ce074
JH
751 push_stack(&attr_stack, read_attr_from_array(builtin_attr), NULL, 0);
752
753 if (git_attr_system())
754 push_stack(&attr_stack,
755 read_attr_from_file(git_etc_gitattributes(), 1),
756 NULL, 0);
6df42ab9 757
2527bbce
PT
758 if (!git_attributes_file)
759 git_attributes_file = xdg_config_home("attributes");
4c0ce074
JH
760 if (git_attributes_file)
761 push_stack(&attr_stack,
762 read_attr_from_file(git_attributes_file, 1),
763 NULL, 0);
f48fd688 764
909ca7b9
JH
765 if (!is_bare_repository() || direction == GIT_ATTR_INDEX) {
766 elem = read_attr(GITATTRIBUTES_FILE, 1);
4c0ce074 767 push_stack(&attr_stack, elem, xstrdup(""), 0);
909ca7b9 768 debug_push(elem);
f48fd688 769 }
909ca7b9 770
f0056f64
JK
771 if (startup_info->have_repository)
772 elem = read_attr_from_file(git_path_info_attributes(), 1);
773 else
774 elem = NULL;
775
909ca7b9
JH
776 if (!elem)
777 elem = xcalloc(1, sizeof(*elem));
4c0ce074 778 push_stack(&attr_stack, elem, NULL, 0);
f48fd688
JH
779}
780
9db9eecf 781static void prepare_attr_stack(const char *path, int dirlen)
d0bfd026
JH
782{
783 struct attr_stack *elem, *info;
a8727017
MH
784 const char *cp;
785
d0bfd026
JH
786 /*
787 * At the bottom of the attribute stack is the built-in
6df42ab9
PO
788 * set of attribute definitions, followed by the contents
789 * of $(prefix)/etc/gitattributes and a file specified by
790 * core.attributesfile. Then, contents from
d0bfd026
JH
791 * .gitattribute files from directories closer to the
792 * root to the ones in deeper directories are pushed
793 * to the stack. Finally, at the very top of the stack
794 * we always keep the contents of $GIT_DIR/info/attributes.
795 *
796 * When checking, we use entries from near the top of the
797 * stack, preferring $GIT_DIR/info/attributes, then
798 * .gitattributes in deeper directories to shallower ones,
799 * and finally use the built-in set as the default.
800 */
7373eab4 801 bootstrap_attr_stack();
d0bfd026
JH
802
803 /*
804 * Pop the "info" one that is always at the top of the stack.
805 */
806 info = attr_stack;
807 attr_stack = info->prev;
808
809 /*
810 * Pop the ones from directories that are not the prefix of
c432ef99
JH
811 * the path we are checking. Break out of the loop when we see
812 * the root one (whose origin is an empty string "") or the builtin
813 * one (whose origin is NULL) without popping it.
d0bfd026 814 */
77f7f822 815 while (attr_stack->origin) {
d0bfd026
JH
816 int namelen = strlen(attr_stack->origin);
817
818 elem = attr_stack;
819 if (namelen <= dirlen &&
1afca444
JK
820 !strncmp(elem->origin, path, namelen) &&
821 (!namelen || path[namelen] == '/'))
d0bfd026
JH
822 break;
823
824 debug_pop(elem);
825 attr_stack = elem->prev;
826 free_attr_elem(elem);
827 }
828
829 /*
830 * Read from parent directories and push them down
831 */
4191e80a 832 if (!is_bare_repository() || direction == GIT_ATTR_INDEX) {
c432ef99
JH
833 /*
834 * bootstrap_attr_stack() should have added, and the
835 * above loop should have stopped before popping, the
836 * root element whose attr_stack->origin is set to an
837 * empty string.
838 */
97410b27 839 struct strbuf pathbuf = STRBUF_INIT;
2d35d556 840
c432ef99 841 assert(attr_stack->origin);
97410b27 842 while (1) {
4c0ce074
JH
843 size_t len = strlen(attr_stack->origin);
844 char *origin;
845
2d35d556
RS
846 if (dirlen <= len)
847 break;
97410b27
BC
848 cp = memchr(path + len + 1, '/', dirlen - len - 1);
849 if (!cp)
850 cp = path + dirlen;
4c0ce074
JH
851 strbuf_addf(&pathbuf,
852 "%.*s/%s", (int)(cp - path), path,
853 GITATTRIBUTES_FILE);
f66cf96d 854 elem = read_attr(pathbuf.buf, 0);
97410b27 855 strbuf_setlen(&pathbuf, cp - path);
4c0ce074
JH
856 origin = strbuf_detach(&pathbuf, &len);
857 push_stack(&attr_stack, elem, origin, len);
2d35d556
RS
858 debug_push(elem);
859 }
d0bfd026 860
97410b27
BC
861 strbuf_release(&pathbuf);
862 }
d4c98565 863
d0bfd026
JH
864 /*
865 * Finally push the "info" one at the top of the stack.
866 */
4c0ce074 867 push_stack(&attr_stack, info, NULL, 0);
d0bfd026
JH
868}
869
870static int path_matches(const char *pathname, int pathlen,
bd2f371d 871 int basename_offset,
82dce998 872 const struct pattern *pat,
d0bfd026
JH
873 const char *base, int baselen)
874{
82dce998
NTND
875 const char *pattern = pat->pattern;
876 int prefix = pat->nowildcardlen;
dc09e9ec 877 int isdir = (pathlen && pathname[pathlen - 1] == '/');
82dce998 878
dc09e9ec 879 if ((pat->flags & EXC_FLAG_MUSTBEDIR) && !isdir)
94bc671a
JNA
880 return 0;
881
82dce998 882 if (pat->flags & EXC_FLAG_NODIR) {
bd2f371d 883 return match_basename(pathname + basename_offset,
dc09e9ec 884 pathlen - basename_offset - isdir,
82dce998
NTND
885 pattern, prefix,
886 pat->patternlen, pat->flags);
d0bfd026 887 }
dc09e9ec 888 return match_pathname(pathname, pathlen - isdir,
82dce998
NTND
889 base, baselen,
890 pattern, prefix, pat->patternlen, pat->flags);
d0bfd026
JH
891}
892
685b2925 893static int macroexpand_one(struct all_attrs_item *all_attrs, int nr, int rem);
ec775c41 894
685b2925 895static int fill_one(const char *what, struct all_attrs_item *all_attrs,
60a12722 896 const struct match_attr *a, int rem)
515106fa 897{
515106fa
JH
898 int i;
899
685b2925 900 for (i = a->num_attr - 1; rem > 0 && i >= 0; i--) {
e810e063 901 const struct git_attr *attr = a->state[i].attr;
685b2925 902 const char **n = &(all_attrs[attr->attr_nr].value);
a5e92abd 903 const char *v = a->state[i].setto;
515106fa
JH
904
905 if (*n == ATTR__UNKNOWN) {
426c27b7 906 debug_set(what,
712efb1a 907 a->is_macro ? a->u.attr->name : a->u.pat.pattern,
426c27b7 908 attr, v);
515106fa
JH
909 *n = v;
910 rem--;
685b2925 911 rem = macroexpand_one(all_attrs, attr->attr_nr, rem);
515106fa
JH
912 }
913 }
914 return rem;
915}
916
bd2f371d 917static int fill(const char *path, int pathlen, int basename_offset,
685b2925
BW
918 struct attr_stack *stk, struct all_attrs_item *all_attrs,
919 int rem)
d0bfd026 920{
515106fa 921 int i;
d0bfd026
JH
922 const char *base = stk->origin ? stk->origin : "";
923
924 for (i = stk->num_matches - 1; 0 < rem && 0 <= i; i--) {
e810e063 925 const struct match_attr *a = stk->attrs[i];
f48fd688
JH
926 if (a->is_macro)
927 continue;
bd2f371d 928 if (path_matches(path, pathlen, basename_offset,
82dce998 929 &a->u.pat, base, stk->originlen))
685b2925 930 rem = fill_one("fill", all_attrs, a, rem);
d0bfd026
JH
931 }
932 return rem;
933}
934
685b2925 935static int macroexpand_one(struct all_attrs_item *all_attrs, int nr, int rem)
f48fd688 936{
60a12722 937 const struct all_attrs_item *item = &all_attrs[nr];
f48fd688 938
60a12722
BW
939 if (item->macro && item->value == ATTR__TRUE)
940 return fill_one("expand", all_attrs, item->macro, rem);
941 else
ec775c41 942 return rem;
60a12722 943}
ec775c41 944
60a12722
BW
945/*
946 * Marks the attributes which are macros based on the attribute stack.
947 * This prevents having to search through the attribute stack each time
948 * a macro needs to be expanded during the fill stage.
949 */
950static void determine_macros(struct all_attrs_item *all_attrs,
951 const struct attr_stack *stack)
952{
953 for (; stack; stack = stack->prev) {
954 int i;
955 for (i = stack->num_matches - 1; i >= 0; i--) {
956 const struct match_attr *ma = stack->attrs[i];
957 if (ma->is_macro) {
958 int n = ma->u.attr->attr_nr;
959 if (!all_attrs[n].macro) {
960 all_attrs[n].macro = ma;
961 }
962 }
ec775c41 963 }
4b0c6961 964 }
f48fd688
JH
965}
966
2d721744 967/*
685b2925
BW
968 * Collect attributes for path into the array pointed to by check->all_attrs.
969 * If check->check_nr is non-zero, only attributes in check[] are collected.
970 * Otherwise all attributes are collected.
2d721744 971 */
6bc2e3f7 972static void collect_some_attrs(const char *path, struct attr_check *check)
d0bfd026
JH
973{
974 struct attr_stack *stk;
9db9eecf 975 int i, pathlen, rem, dirlen;
bd2f371d
JH
976 const char *cp, *last_slash = NULL;
977 int basename_offset;
9db9eecf
NTND
978
979 for (cp = path; *cp; cp++) {
980 if (*cp == '/' && cp[1])
981 last_slash = cp;
982 }
983 pathlen = cp - path;
984 if (last_slash) {
bd2f371d 985 basename_offset = last_slash + 1 - path;
9db9eecf
NTND
986 dirlen = last_slash - path;
987 } else {
bd2f371d 988 basename_offset = 0;
9db9eecf
NTND
989 dirlen = 0;
990 }
d0bfd026 991
9db9eecf 992 prepare_attr_stack(path, dirlen);
685b2925 993 all_attrs_init(&g_attr_hashmap, check);
60a12722 994 determine_macros(check->all_attrs, attr_stack);
685b2925 995
60a12722 996 if (check->nr) {
06a604e6 997 rem = 0;
6bc2e3f7 998 for (i = 0; i < check->nr; i++) {
60a12722
BW
999 int n = check->items[i].attr->attr_nr;
1000 struct all_attrs_item *item = &check->all_attrs[n];
1001 if (item->macro) {
1002 item->value = ATTR__UNSET;
06a604e6
NTND
1003 rem++;
1004 }
1005 }
6bc2e3f7 1006 if (rem == check->nr)
06a604e6
NTND
1007 return;
1008 }
d0bfd026 1009
685b2925 1010 rem = check->all_attrs_nr;
f48fd688 1011 for (stk = attr_stack; 0 < rem && stk; stk = stk->prev)
685b2925 1012 rem = fill(path, pathlen, basename_offset, stk, check->all_attrs, rem);
2d721744
MH
1013}
1014
6bc2e3f7 1015int git_check_attr(const char *path, struct attr_check *check)
2d721744
MH
1016{
1017 int i;
1018
6bc2e3f7 1019 collect_some_attrs(path, check);
f48fd688 1020
6bc2e3f7 1021 for (i = 0; i < check->nr; i++) {
685b2925
BW
1022 size_t n = check->items[i].attr->attr_nr;
1023 const char *value = check->all_attrs[n].value;
515106fa
JH
1024 if (value == ATTR__UNKNOWN)
1025 value = ATTR__UNSET;
6bc2e3f7 1026 check->items[i].value = value;
515106fa 1027 }
f48fd688 1028
d0bfd026
JH
1029 return 0;
1030}
06f33c17 1031
7f864111 1032void git_all_attrs(const char *path, struct attr_check *check)
ee548df3 1033{
7f864111 1034 int i;
ee548df3 1035
7f864111 1036 attr_check_reset(check);
6bc2e3f7 1037 collect_some_attrs(path, check);
ee548df3 1038
685b2925
BW
1039 for (i = 0; i < check->all_attrs_nr; i++) {
1040 const char *name = check->all_attrs[i].attr->name;
1041 const char *value = check->all_attrs[i].value;
7f864111
JH
1042 struct attr_check_item *item;
1043 if (value == ATTR__UNSET || value == ATTR__UNKNOWN)
1044 continue;
1045 item = attr_check_append(check, git_attr(name));
1046 item->value = value;
ee548df3 1047 }
ee548df3
MH
1048}
1049
06f33c17
JH
1050void git_attr_set_direction(enum git_attr_direction new, struct index_state *istate)
1051{
1052 enum git_attr_direction old = direction;
4191e80a
NTND
1053
1054 if (is_bare_repository() && new != GIT_ATTR_INDEX)
1055 die("BUG: non-INDEX attr direction in a bare repo");
1056
06f33c17
JH
1057 direction = new;
1058 if (new != old)
1059 drop_attr_stack();
1060 use_index = istate;
1061}
1a600b75
BW
1062
1063void attr_start(void)
1064{
1065#ifndef NO_PTHREADS
1066 pthread_mutex_init(&g_attr_hashmap.mutex, NULL);
1067#endif
1068}