tree-walk: be more specific about corrupt tree errors
[git/git.git] / tree-walk.c
CommitLineData
1b0c7174
JH
1#include "cache.h"
2#include "tree-walk.h"
e6c111b4 3#include "unpack-trees.h"
bc96cc87 4#include "dir.h"
8e440259 5#include "tree.h"
64acde94 6#include "pathspec.h"
1b0c7174 7
4651ece8
LT
8static const char *get_mode(const char *str, unsigned int *modep)
9{
10 unsigned char c;
11 unsigned int mode = 0;
12
64cc1c09
MK
13 if (*str == ' ')
14 return NULL;
15
4651ece8
LT
16 while ((c = *str++) != ' ') {
17 if (c < '0' || c > '7')
18 return NULL;
19 mode = (mode << 3) + (c - '0');
20 }
21 *modep = mode;
22 return str;
23}
24
64cc1c09 25static void decode_tree_entry(struct tree_desc *desc, const char *buf, unsigned long size)
4651ece8
LT
26{
27 const char *path;
28 unsigned int mode, len;
29
2edffef2
JK
30 if (size < 23 || buf[size - 21])
31 die(_("too-short tree object"));
64cc1c09 32
4651ece8 33 path = get_mode(buf, &mode);
2edffef2
JK
34 if (!path)
35 die(_("malformed mode in tree entry for tree"));
36 if (!*path)
37 die(_("empty filename in tree entry for tree"));
4651ece8
LT
38 len = strlen(path) + 1;
39
40 /* Initialize the descriptor entry */
41 desc->entry.path = path;
7146e66f 42 desc->entry.mode = canon_mode(mode);
7d924c91 43 desc->entry.oid = (const struct object_id *)(path + len);
4651ece8
LT
44}
45
6fda5e51
LT
46void init_tree_desc(struct tree_desc *desc, const void *buffer, unsigned long size)
47{
48 desc->buffer = buffer;
49 desc->size = size;
4651ece8
LT
50 if (size)
51 decode_tree_entry(desc, buffer, size);
6fda5e51
LT
52}
53
1b0c7174
JH
54void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1)
55{
56 unsigned long size = 0;
57 void *buf = NULL;
58
59 if (sha1) {
8e440259 60 buf = read_object_with_reference(sha1, tree_type, &size, NULL);
1b0c7174
JH
61 if (!buf)
62 die("unable to read tree %s", sha1_to_hex(sha1));
63 }
6fda5e51 64 init_tree_desc(desc, buf, size);
1b0c7174
JH
65 return buf;
66}
67
1b0c7174
JH
68static void entry_clear(struct name_entry *a)
69{
70 memset(a, 0, sizeof(*a));
71}
72
73static void entry_extract(struct tree_desc *t, struct name_entry *a)
74{
4651ece8 75 *a = t->entry;
1b0c7174
JH
76}
77
78void update_tree_entry(struct tree_desc *desc)
79{
6fda5e51 80 const void *buf = desc->buffer;
7d924c91 81 const unsigned char *end = desc->entry.oid->hash + 20;
1b0c7174 82 unsigned long size = desc->size;
4651ece8 83 unsigned long len = end - (const unsigned char *)buf;
1b0c7174
JH
84
85 if (size < len)
2edffef2 86 die(_("too-short tree file"));
4651ece8
LT
87 buf = end;
88 size -= len;
89 desc->buffer = buf;
90 desc->size = size;
91 if (size)
92 decode_tree_entry(desc, buf, size);
1b0c7174
JH
93}
94
4c068a98
LT
95int tree_entry(struct tree_desc *desc, struct name_entry *entry)
96{
4651ece8 97 if (!desc->size)
4c068a98
LT
98 return 0;
99
4651ece8
LT
100 *entry = desc->entry;
101 update_tree_entry(desc);
4c068a98
LT
102 return 1;
103}
104
40d934df
LT
105void setup_traverse_info(struct traverse_info *info, const char *base)
106{
107 int pathlen = strlen(base);
bcbe5a51 108 static struct traverse_info dummy;
40d934df
LT
109
110 memset(info, 0, sizeof(*info));
111 if (pathlen && base[pathlen-1] == '/')
112 pathlen--;
113 info->pathlen = pathlen ? pathlen + 1 : 0;
114 info->name.path = base;
7d924c91 115 info->name.oid = (void *)(base + pathlen + 1);
bcbe5a51
LT
116 if (pathlen)
117 info->prev = &dummy;
40d934df
LT
118}
119
120char *make_traverse_path(char *path, const struct traverse_info *info, const struct name_entry *n)
121{
0de16337 122 int len = tree_entry_len(n);
40d934df
LT
123 int pathlen = info->pathlen;
124
125 path[pathlen + len] = 0;
126 for (;;) {
127 memcpy(path + pathlen, n->path, len);
128 if (!pathlen)
129 break;
130 path[--pathlen] = '/';
131 n = &info->name;
0de16337 132 len = tree_entry_len(n);
40d934df
LT
133 info = info->prev;
134 pathlen -= len;
135 }
136 return path;
137}
138
1ee26571
JH
139struct tree_desc_skip {
140 struct tree_desc_skip *prev;
141 const void *ptr;
142};
143
144struct tree_desc_x {
145 struct tree_desc d;
146 struct tree_desc_skip *skip;
147};
148
1ee26571
JH
149static int check_entry_match(const char *a, int a_len, const char *b, int b_len)
150{
151 /*
152 * The caller wants to pick *a* from a tree or nothing.
153 * We are looking at *b* in a tree.
154 *
155 * (0) If a and b are the same name, we are trivially happy.
156 *
157 * There are three possibilities where *a* could be hiding
158 * behind *b*.
159 *
160 * (1) *a* == "t", *b* == "ab" i.e. *b* sorts earlier than *a* no
161 * matter what.
162 * (2) *a* == "t", *b* == "t-2" and "t" is a subtree in the tree;
163 * (3) *a* == "t-2", *b* == "t" and "t-2" is a blob in the tree.
164 *
165 * Otherwise we know *a* won't appear in the tree without
166 * scanning further.
167 */
168
169 int cmp = name_compare(a, a_len, b, b_len);
170
171 /* Most common case first -- reading sync'd trees */
172 if (!cmp)
173 return cmp;
174
175 if (0 < cmp) {
176 /* a comes after b; it does not matter if it is case (3)
177 if (b_len < a_len && !memcmp(a, b, b_len) && a[b_len] < '/')
178 return 1;
179 */
180 return 1; /* keep looking */
181 }
182
183 /* b comes after a; are we looking at case (2)? */
184 if (a_len < b_len && !memcmp(a, b, a_len) && b[a_len] < '/')
185 return 1; /* keep looking */
186
187 return -1; /* a cannot appear in the tree */
188}
189
190/*
191 * From the extended tree_desc, extract the first name entry, while
192 * paying attention to the candidate "first" name. Most importantly,
193 * when looking for an entry, if there are entries that sorts earlier
194 * in the tree object representation than that name, skip them and
195 * process the named entry first. We will remember that we haven't
196 * processed the first entry yet, and in the later call skip the
197 * entry we processed early when update_extended_entry() is called.
198 *
199 * E.g. if the underlying tree object has these entries:
200 *
201 * blob "t-1"
202 * blob "t-2"
203 * tree "t"
204 * blob "t=1"
205 *
206 * and the "first" asks for "t", remember that we still need to
207 * process "t-1" and "t-2" but extract "t". After processing the
208 * entry "t" from this call, the caller will let us know by calling
209 * update_extended_entry() that we can remember "t" has been processed
210 * already.
211 */
212
213static void extended_entry_extract(struct tree_desc_x *t,
214 struct name_entry *a,
215 const char *first,
216 int first_len)
217{
218 const char *path;
219 int len;
220 struct tree_desc probe;
221 struct tree_desc_skip *skip;
222
223 /*
224 * Extract the first entry from the tree_desc, but skip the
225 * ones that we already returned in earlier rounds.
226 */
227 while (1) {
228 if (!t->d.size) {
229 entry_clear(a);
230 break; /* not found */
231 }
232 entry_extract(&t->d, a);
233 for (skip = t->skip; skip; skip = skip->prev)
234 if (a->path == skip->ptr)
235 break; /* found */
236 if (!skip)
237 break;
238 /* We have processed this entry already. */
239 update_tree_entry(&t->d);
240 }
241
242 if (!first || !a->path)
243 return;
244
245 /*
246 * The caller wants "first" from this tree, or nothing.
247 */
248 path = a->path;
0de16337 249 len = tree_entry_len(a);
1ee26571
JH
250 switch (check_entry_match(first, first_len, path, len)) {
251 case -1:
252 entry_clear(a);
253 case 0:
254 return;
255 default:
256 break;
257 }
258
259 /*
260 * We need to look-ahead -- we suspect that a subtree whose
261 * name is "first" may be hiding behind the current entry "path".
262 */
263 probe = t->d;
264 while (probe.size) {
265 entry_extract(&probe, a);
266 path = a->path;
0de16337 267 len = tree_entry_len(a);
1ee26571
JH
268 switch (check_entry_match(first, first_len, path, len)) {
269 case -1:
270 entry_clear(a);
271 case 0:
272 return;
273 default:
274 update_tree_entry(&probe);
275 break;
276 }
277 /* keep looking */
278 }
279 entry_clear(a);
280}
281
282static void update_extended_entry(struct tree_desc_x *t, struct name_entry *a)
283{
284 if (t->d.entry.path == a->path) {
285 update_tree_entry(&t->d);
286 } else {
287 /* we have returned this entry early */
288 struct tree_desc_skip *skip = xmalloc(sizeof(*skip));
289 skip->ptr = a->path;
290 skip->prev = t->skip;
291 t->skip = skip;
292 }
293}
294
295static void free_extended_entry(struct tree_desc_x *t)
296{
297 struct tree_desc_skip *p, *s;
298
299 for (s = t->skip; s; s = p) {
300 p = s->prev;
301 free(s);
302 }
303}
304
2842c0f9
JH
305static inline int prune_traversal(struct name_entry *e,
306 struct traverse_info *info,
307 struct strbuf *base,
308 int still_interesting)
309{
310 if (!info->pathspec || still_interesting == 2)
311 return 2;
312 if (still_interesting < 0)
313 return still_interesting;
314 return tree_entry_interesting(e, base, 0, info->pathspec);
315}
316
5803c6f8 317int traverse_trees(int n, struct tree_desc *t, struct traverse_info *info)
1b0c7174 318{
e6c111b4 319 int error = 0;
1b0c7174 320 struct name_entry *entry = xmalloc(n*sizeof(*entry));
1ee26571
JH
321 int i;
322 struct tree_desc_x *tx = xcalloc(n, sizeof(*tx));
2842c0f9
JH
323 struct strbuf base = STRBUF_INIT;
324 int interesting = 1;
d9c2bd56 325 char *traverse_path;
1ee26571
JH
326
327 for (i = 0; i < n; i++)
328 tx[i].d = t[i];
1b0c7174 329
2842c0f9
JH
330 if (info->prev) {
331 strbuf_grow(&base, info->pathlen);
332 make_traverse_path(base.buf, info->prev, &info->name);
333 base.buf[info->pathlen-1] = '/';
334 strbuf_setlen(&base, info->pathlen);
d9c2bd56
DT
335 traverse_path = xstrndup(base.buf, info->pathlen);
336 } else {
337 traverse_path = xstrndup(info->name.path, info->pathlen);
2842c0f9 338 }
d9c2bd56 339 info->traverse_path = traverse_path;
1b0c7174 340 for (;;) {
a04f8196 341 int trees_used;
1ee26571
JH
342 unsigned long mask, dirmask;
343 const char *first = NULL;
344 int first_len = 0;
27c0f768 345 struct name_entry *e = NULL;
1ee26571
JH
346 int len;
347
348 for (i = 0; i < n; i++) {
349 e = entry + i;
350 extended_entry_extract(tx + i, e, NULL, 0);
351 }
1b0c7174 352
1ee26571
JH
353 /*
354 * A tree may have "t-2" at the current location even
355 * though it may have "t" that is a subtree behind it,
356 * and another tree may return "t". We want to grab
357 * all "t" from all trees to match in such a case.
358 */
1b0c7174 359 for (i = 0; i < n; i++) {
1ee26571
JH
360 e = entry + i;
361 if (!e->path)
1b0c7174 362 continue;
0de16337 363 len = tree_entry_len(e);
1ee26571
JH
364 if (!first) {
365 first = e->path;
366 first_len = len;
367 continue;
368 }
369 if (name_compare(e->path, len, first, first_len) < 0) {
370 first = e->path;
371 first_len = len;
372 }
373 }
374
375 if (first) {
376 for (i = 0; i < n; i++) {
377 e = entry + i;
378 extended_entry_extract(tx + i, e, first, first_len);
379 /* Cull the ones that are not the earliest */
380 if (!e->path)
1b0c7174 381 continue;
0de16337 382 len = tree_entry_len(e);
1ee26571
JH
383 if (name_compare(e->path, len, first, first_len))
384 entry_clear(e);
1b0c7174 385 }
1ee26571
JH
386 }
387
388 /* Now we have in entry[i] the earliest name from the trees */
389 mask = 0;
390 dirmask = 0;
391 for (i = 0; i < n; i++) {
392 if (!entry[i].path)
393 continue;
1b0c7174 394 mask |= 1ul << i;
91e4f036
LT
395 if (S_ISDIR(entry[i].mode))
396 dirmask |= 1ul << i;
2842c0f9 397 e = &entry[i];
1b0c7174
JH
398 }
399 if (!mask)
400 break;
2842c0f9
JH
401 interesting = prune_traversal(e, info, &base, interesting);
402 if (interesting < 0)
403 break;
404 if (interesting) {
a04f8196
SB
405 trees_used = info->fn(n, mask, dirmask, entry, info);
406 if (trees_used < 0) {
407 error = trees_used;
2842c0f9
JH
408 if (!info->show_all_errors)
409 break;
410 }
a04f8196 411 mask &= trees_used;
e6c111b4 412 }
1ee26571 413 for (i = 0; i < n; i++)
5803c6f8 414 if (mask & (1ul << i))
1ee26571 415 update_extended_entry(tx + i, entry + i);
1b0c7174
JH
416 }
417 free(entry);
1ee26571
JH
418 for (i = 0; i < n; i++)
419 free_extended_entry(tx + i);
420 free(tx);
d9c2bd56
DT
421 free(traverse_path);
422 info->traverse_path = NULL;
2842c0f9 423 strbuf_release(&base);
e6c111b4 424 return error;
1b0c7174
JH
425}
426
275721c2
DT
427struct dir_state {
428 void *tree;
429 unsigned long size;
430 unsigned char sha1[20];
431};
432
4dcff634
JH
433static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char *result, unsigned *mode)
434{
435 int namelen = strlen(name);
436 while (t->size) {
437 const char *entry;
ce6663a9 438 const struct object_id *oid;
4dcff634
JH
439 int entrylen, cmp;
440
ce6663a9 441 oid = tree_entry_extract(t, &entry, mode);
0de16337 442 entrylen = tree_entry_len(&t->entry);
4dcff634 443 update_tree_entry(t);
4dcff634
JH
444 if (entrylen > namelen)
445 continue;
446 cmp = memcmp(name, entry, entrylen);
447 if (cmp > 0)
448 continue;
449 if (cmp < 0)
450 break;
451 if (entrylen == namelen) {
ce6663a9 452 hashcpy(result, oid->hash);
4dcff634
JH
453 return 0;
454 }
455 if (name[entrylen] != '/')
456 continue;
457 if (!S_ISDIR(*mode))
458 break;
459 if (++entrylen == namelen) {
ce6663a9 460 hashcpy(result, oid->hash);
4dcff634
JH
461 return 0;
462 }
ce6663a9 463 return get_tree_entry(oid->hash, name + entrylen, result, mode);
4dcff634
JH
464 }
465 return -1;
466}
467
468int get_tree_entry(const unsigned char *tree_sha1, const char *name, unsigned char *sha1, unsigned *mode)
469{
470 int retval;
471 void *tree;
6fda5e51 472 unsigned long size;
d93b7d1c 473 unsigned char root[20];
4dcff634 474
6fda5e51 475 tree = read_object_with_reference(tree_sha1, tree_type, &size, root);
4dcff634
JH
476 if (!tree)
477 return -1;
d93b7d1c
JK
478
479 if (name[0] == '\0') {
480 hashcpy(sha1, root);
ef006503 481 free(tree);
d93b7d1c
JK
482 return 0;
483 }
484
5fb8c05f
JH
485 if (!size) {
486 retval = -1;
487 } else {
488 struct tree_desc t;
489 init_tree_desc(&t, tree, size);
490 retval = find_tree_entry(&t, name, sha1, mode);
491 }
4dcff634
JH
492 free(tree);
493 return retval;
494}
2c389fc8 495
275721c2
DT
496/*
497 * This is Linux's built-in max for the number of symlinks to follow.
498 * That limit, of course, does not affect git, but it's a reasonable
499 * choice.
500 */
501#define GET_TREE_ENTRY_FOLLOW_SYMLINKS_MAX_LINKS 40
502
503/**
504 * Find a tree entry by following symlinks in tree_sha (which is
505 * assumed to be the root of the repository). In the event that a
506 * symlink points outside the repository (e.g. a link to /foo or a
507 * root-level link to ../foo), the portion of the link which is
508 * outside the repository will be returned in result_path, and *mode
509 * will be set to 0. It is assumed that result_path is uninitialized.
510 * If there are no symlinks, or the end result of the symlink chain
511 * points to an object inside the repository, result will be filled in
512 * with the sha1 of the found object, and *mode will hold the mode of
513 * the object.
514 *
515 * See the code for enum follow_symlink_result for a description of
516 * the return values.
517 */
518enum follow_symlinks_result get_tree_entry_follow_symlinks(unsigned char *tree_sha1, const char *name, unsigned char *result, struct strbuf *result_path, unsigned *mode)
519{
520 int retval = MISSING_OBJECT;
521 struct dir_state *parents = NULL;
522 size_t parents_alloc = 0;
523 ssize_t parents_nr = 0;
524 unsigned char current_tree_sha1[20];
525 struct strbuf namebuf = STRBUF_INIT;
526 struct tree_desc t;
527 int follows_remaining = GET_TREE_ENTRY_FOLLOW_SYMLINKS_MAX_LINKS;
528 int i;
529
530 init_tree_desc(&t, NULL, 0UL);
531 strbuf_init(result_path, 0);
532 strbuf_addstr(&namebuf, name);
533 hashcpy(current_tree_sha1, tree_sha1);
534
535 while (1) {
536 int find_result;
537 char *first_slash;
538 char *remainder = NULL;
539
540 if (!t.buffer) {
541 void *tree;
542 unsigned char root[20];
543 unsigned long size;
544 tree = read_object_with_reference(current_tree_sha1,
545 tree_type, &size,
546 root);
547 if (!tree)
548 goto done;
549
550 ALLOC_GROW(parents, parents_nr + 1, parents_alloc);
551 parents[parents_nr].tree = tree;
552 parents[parents_nr].size = size;
553 hashcpy(parents[parents_nr].sha1, root);
554 parents_nr++;
555
556 if (namebuf.buf[0] == '\0') {
557 hashcpy(result, root);
558 retval = FOUND;
559 goto done;
560 }
561
562 if (!size)
563 goto done;
564
565 /* descend */
566 init_tree_desc(&t, tree, size);
567 }
568
569 /* Handle symlinks to e.g. a//b by removing leading slashes */
570 while (namebuf.buf[0] == '/') {
571 strbuf_remove(&namebuf, 0, 1);
572 }
573
574 /* Split namebuf into a first component and a remainder */
575 if ((first_slash = strchr(namebuf.buf, '/'))) {
576 *first_slash = 0;
577 remainder = first_slash + 1;
578 }
579
580 if (!strcmp(namebuf.buf, "..")) {
581 struct dir_state *parent;
582 /*
583 * We could end up with .. in the namebuf if it
584 * appears in a symlink.
585 */
586
587 if (parents_nr == 1) {
588 if (remainder)
589 *first_slash = '/';
590 strbuf_add(result_path, namebuf.buf,
591 namebuf.len);
592 *mode = 0;
593 retval = FOUND;
594 goto done;
595 }
596 parent = &parents[parents_nr - 1];
597 free(parent->tree);
598 parents_nr--;
599 parent = &parents[parents_nr - 1];
600 init_tree_desc(&t, parent->tree, parent->size);
601 strbuf_remove(&namebuf, 0, remainder ? 3 : 2);
602 continue;
603 }
604
605 /* We could end up here via a symlink to dir/.. */
606 if (namebuf.buf[0] == '\0') {
607 hashcpy(result, parents[parents_nr - 1].sha1);
608 retval = FOUND;
609 goto done;
610 }
611
612 /* Look up the first (or only) path component in the tree. */
613 find_result = find_tree_entry(&t, namebuf.buf,
614 current_tree_sha1, mode);
615 if (find_result) {
616 goto done;
617 }
618
619 if (S_ISDIR(*mode)) {
620 if (!remainder) {
621 hashcpy(result, current_tree_sha1);
622 retval = FOUND;
623 goto done;
624 }
625 /* Descend the tree */
626 t.buffer = NULL;
627 strbuf_remove(&namebuf, 0,
628 1 + first_slash - namebuf.buf);
629 } else if (S_ISREG(*mode)) {
630 if (!remainder) {
631 hashcpy(result, current_tree_sha1);
632 retval = FOUND;
633 } else {
634 retval = NOT_DIR;
635 }
636 goto done;
637 } else if (S_ISLNK(*mode)) {
638 /* Follow a symlink */
639 unsigned long link_len;
640 size_t len;
641 char *contents, *contents_start;
642 struct dir_state *parent;
643 enum object_type type;
644
645 if (follows_remaining-- == 0) {
646 /* Too many symlinks followed */
647 retval = SYMLINK_LOOP;
648 goto done;
649 }
650
651 /*
652 * At this point, we have followed at a least
653 * one symlink, so on error we need to report this.
654 */
655 retval = DANGLING_SYMLINK;
656
657 contents = read_sha1_file(current_tree_sha1, &type,
658 &link_len);
659
660 if (!contents)
661 goto done;
662
663 if (contents[0] == '/') {
664 strbuf_addstr(result_path, contents);
665 free(contents);
666 *mode = 0;
667 retval = FOUND;
668 goto done;
669 }
670
671 if (remainder)
672 len = first_slash - namebuf.buf;
673 else
674 len = namebuf.len;
675
676 contents_start = contents;
677
678 parent = &parents[parents_nr - 1];
679 init_tree_desc(&t, parent->tree, parent->size);
680 strbuf_splice(&namebuf, 0, len,
681 contents_start, link_len);
682 if (remainder)
683 namebuf.buf[link_len] = '/';
684 free(contents);
685 }
686 }
687done:
688 for (i = 0; i < parents_nr; i++)
689 free(parents[i].tree);
690 free(parents);
691
692 strbuf_release(&namebuf);
693 return retval;
694}
695
93d93537
NTND
696static int match_entry(const struct pathspec_item *item,
697 const struct name_entry *entry, int pathlen,
58c4d666 698 const char *match, int matchlen,
c3a47ca9 699 enum interesting *never_interesting)
58c4d666
NTND
700{
701 int m = -1; /* signals that we haven't called strncmp() */
702
93d93537
NTND
703 if (item->magic & PATHSPEC_ICASE)
704 /*
705 * "Never interesting" trick requires exact
706 * matching. We could do something clever with inexact
707 * matching, but it's trickier (and not to forget that
708 * strcasecmp is locale-dependent, at least in
709 * glibc). Just disable it for now. It can't be worse
710 * than the wildcard's codepath of '[Tt][Hi][Is][Ss]'
711 * pattern.
712 */
713 *never_interesting = entry_not_interesting;
714 else if (*never_interesting != entry_not_interesting) {
58c4d666
NTND
715 /*
716 * We have not seen any match that sorts later
717 * than the current path.
718 */
719
720 /*
721 * Does match sort strictly earlier than path
722 * with their common parts?
723 */
724 m = strncmp(match, entry->path,
725 (matchlen < pathlen) ? matchlen : pathlen);
726 if (m < 0)
727 return 0;
728
729 /*
730 * If we come here even once, that means there is at
731 * least one pathspec that would sort equal to or
732 * later than the path we are currently looking at.
733 * In other words, if we have never reached this point
734 * after iterating all pathspecs, it means all
735 * pathspecs are either outside of base, or inside the
736 * base but sorts strictly earlier than the current
737 * one. In either case, they will never match the
738 * subsequent entries. In such a case, we initialized
739 * the variable to -1 and that is what will be
740 * returned, allowing the caller to terminate early.
741 */
c3a47ca9 742 *never_interesting = entry_not_interesting;
58c4d666
NTND
743 }
744
745 if (pathlen > matchlen)
746 return 0;
747
748 if (matchlen > pathlen) {
749 if (match[pathlen] != '/')
750 return 0;
74b4f7f2 751 if (!S_ISDIR(entry->mode) && !S_ISGITLINK(entry->mode))
58c4d666
NTND
752 return 0;
753 }
754
755 if (m == -1)
756 /*
757 * we cheated and did not do strncmp(), so we do
758 * that here.
759 */
93d93537 760 m = ps_strncmp(item, match, entry->path, pathlen);
58c4d666
NTND
761
762 /*
763 * If common part matched earlier then it is a hit,
764 * because we rejected the case where path is not a
765 * leading directory and is shorter than match.
766 */
767 if (!m)
93d93537
NTND
768 /*
769 * match_entry does not check if the prefix part is
770 * matched case-sensitively. If the entry is a
771 * directory and part of prefix, it'll be rematched
772 * eventually by basecmp with special treatment for
773 * the prefix.
774 */
58c4d666
NTND
775 return 1;
776
777 return 0;
778}
779
93d93537
NTND
780/* :(icase)-aware string compare */
781static int basecmp(const struct pathspec_item *item,
782 const char *base, const char *match, int len)
783{
784 if (item->magic & PATHSPEC_ICASE) {
785 int ret, n = len > item->prefix ? item->prefix : len;
786 ret = strncmp(base, match, n);
787 if (ret)
788 return ret;
789 base += n;
790 match += n;
791 len -= n;
792 }
793 return ps_strncmp(item, base, match, len);
794}
795
796static int match_dir_prefix(const struct pathspec_item *item,
797 const char *base,
58c4d666
NTND
798 const char *match, int matchlen)
799{
93d93537 800 if (basecmp(item, base, match, matchlen))
58c4d666
NTND
801 return 0;
802
803 /*
804 * If the base is a subdirectory of a path which
805 * was specified, all of them are interesting.
806 */
807 if (!matchlen ||
808 base[matchlen] == '/' ||
809 match[matchlen - 1] == '/')
810 return 1;
811
812 /* Just a random prefix match */
813 return 0;
814}
815
c904cd89
NTND
816/*
817 * Perform matching on the leading non-wildcard part of
818 * pathspec. item->nowildcard_len must be greater than zero. Return
819 * non-zero if base is matched.
820 */
821static int match_wildcard_base(const struct pathspec_item *item,
822 const char *base, int baselen,
823 int *matched)
824{
825 const char *match = item->match;
826 /* the wildcard part is not considered in this function */
827 int matchlen = item->nowildcard_len;
828
829 if (baselen) {
830 int dirlen;
831 /*
832 * Return early if base is longer than the
833 * non-wildcard part but it does not match.
834 */
835 if (baselen >= matchlen) {
836 *matched = matchlen;
93d93537 837 return !basecmp(item, base, match, matchlen);
c904cd89
NTND
838 }
839
840 dirlen = matchlen;
841 while (dirlen && match[dirlen - 1] != '/')
842 dirlen--;
843
844 /*
845 * Return early if base is shorter than the
846 * non-wildcard part but it does not match. Note that
847 * base ends with '/' so we are sure it really matches
848 * directory
849 */
93d93537 850 if (basecmp(item, base, match, baselen))
c904cd89
NTND
851 return 0;
852 *matched = baselen;
853 } else
854 *matched = 0;
855 /*
856 * we could have checked entry against the non-wildcard part
857 * that is not in base and does similar never_interesting
858 * optimization as in match_entry. For now just be happy with
859 * base comparison.
860 */
861 return entry_interesting;
862}
863
2c389fc8
NTND
864/*
865 * Is a tree entry interesting given the pathspec we have?
866 *
1376e507
NTND
867 * Pre-condition: either baselen == base_offset (i.e. empty path)
868 * or base[baselen-1] == '/' (i.e. with trailing slash).
2c389fc8 869 */
ef79b1f8
NTND
870static enum interesting do_match(const struct name_entry *entry,
871 struct strbuf *base, int base_offset,
872 const struct pathspec *ps,
873 int exclude)
2c389fc8
NTND
874{
875 int i;
1376e507 876 int pathlen, baselen = base->len - base_offset;
c3a47ca9 877 enum interesting never_interesting = ps->has_wildcard ?
d688cf07 878 entry_not_interesting : all_entries_not_interesting;
2c389fc8 879
5c6933d2
NTND
880 GUARD_PATHSPEC(ps,
881 PATHSPEC_FROMTOP |
882 PATHSPEC_MAXDEPTH |
bd30c2e4 883 PATHSPEC_LITERAL |
93d93537 884 PATHSPEC_GLOB |
ef79b1f8
NTND
885 PATHSPEC_ICASE |
886 PATHSPEC_EXCLUDE);
8f4f8f45 887
bc96cc87 888 if (!ps->nr) {
6330a171
NTND
889 if (!ps->recursive ||
890 !(ps->magic & PATHSPEC_MAXDEPTH) ||
891 ps->max_depth == -1)
d688cf07
NTND
892 return all_entries_interesting;
893 return within_depth(base->buf + base_offset, baselen,
894 !!S_ISDIR(entry->mode),
895 ps->max_depth) ?
896 entry_interesting : entry_not_interesting;
bc96cc87 897 }
2c389fc8 898
0de16337 899 pathlen = tree_entry_len(entry);
2c389fc8 900
1376e507 901 for (i = ps->nr - 1; i >= 0; i--) {
2c389fc8
NTND
902 const struct pathspec_item *item = ps->items+i;
903 const char *match = item->match;
1376e507 904 const char *base_str = base->buf + base_offset;
c904cd89 905 int matchlen = item->len, matched = 0;
2c389fc8 906
ef79b1f8
NTND
907 if ((!exclude && item->magic & PATHSPEC_EXCLUDE) ||
908 ( exclude && !(item->magic & PATHSPEC_EXCLUDE)))
909 continue;
910
2c389fc8
NTND
911 if (baselen >= matchlen) {
912 /* If it doesn't match, move along... */
93d93537 913 if (!match_dir_prefix(item, base_str, match, matchlen))
d38f2809 914 goto match_wildcards;
bc96cc87 915
6330a171
NTND
916 if (!ps->recursive ||
917 !(ps->magic & PATHSPEC_MAXDEPTH) ||
918 ps->max_depth == -1)
d688cf07 919 return all_entries_interesting;
bc96cc87 920
d688cf07
NTND
921 return within_depth(base_str + matchlen + 1,
922 baselen - matchlen - 1,
923 !!S_ISDIR(entry->mode),
924 ps->max_depth) ?
925 entry_interesting : entry_not_interesting;
2c389fc8
NTND
926 }
927
1b740923 928 /* Either there must be no base, or the base must match. */
93d93537
NTND
929 if (baselen == 0 || !basecmp(item, base_str, match, baselen)) {
930 if (match_entry(item, entry, pathlen,
58c4d666
NTND
931 match + baselen, matchlen - baselen,
932 &never_interesting))
d688cf07 933 return entry_interesting;
f1a2ddbb 934
170260ae 935 if (item->nowildcard_len < item->len) {
bd30c2e4 936 if (!git_fnmatch(item, match + baselen, entry->path,
8c6abbcd 937 item->nowildcard_len - baselen))
d688cf07 938 return entry_interesting;
f1a2ddbb
NTND
939
940 /*
941 * Match all directories. We'll try to
942 * match files later on.
943 */
944 if (ps->recursive && S_ISDIR(entry->mode))
d688cf07 945 return entry_interesting;
f1a2ddbb
NTND
946 }
947
948 continue;
2c389fc8 949 }
d38f2809
NTND
950
951match_wildcards:
170260ae 952 if (item->nowildcard_len == item->len)
d38f2809
NTND
953 continue;
954
c904cd89
NTND
955 if (item->nowildcard_len &&
956 !match_wildcard_base(item, base_str, baselen, &matched))
e4ddb057 957 continue;
c904cd89 958
d38f2809
NTND
959 /*
960 * Concatenate base and entry->path into one and do
961 * fnmatch() on it.
c904cd89
NTND
962 *
963 * While we could avoid concatenation in certain cases
964 * [1], which saves a memcpy and potentially a
965 * realloc, it turns out not worth it. Measurement on
966 * linux-2.6 does not show any clear improvements,
967 * partly because of the nowildcard_len optimization
968 * in git_fnmatch(). Avoid micro-optimizations here.
969 *
970 * [1] if match_wildcard_base() says the base
971 * directory is already matched, we only need to match
972 * the rest, which is shorter so _in theory_ faster.
d38f2809
NTND
973 */
974
975 strbuf_add(base, entry->path, pathlen);
976
bd30c2e4 977 if (!git_fnmatch(item, match, base->buf + base_offset,
8c6abbcd 978 item->nowildcard_len)) {
1376e507 979 strbuf_setlen(base, base_offset + baselen);
d688cf07 980 return entry_interesting;
d38f2809 981 }
1376e507 982 strbuf_setlen(base, base_offset + baselen);
d38f2809
NTND
983
984 /*
985 * Match all directories. We'll try to match files
986 * later on.
8c69c1f9
NTND
987 * max_depth is ignored but we may consider support it
988 * in future, see
989 * http://thread.gmane.org/gmane.comp.version-control.git/163757/focus=163840
d38f2809
NTND
990 */
991 if (ps->recursive && S_ISDIR(entry->mode))
d688cf07 992 return entry_interesting;
2c389fc8
NTND
993 }
994 return never_interesting; /* No matches */
995}
ef79b1f8
NTND
996
997/*
998 * Is a tree entry interesting given the pathspec we have?
999 *
1000 * Pre-condition: either baselen == base_offset (i.e. empty path)
1001 * or base[baselen-1] == '/' (i.e. with trailing slash).
1002 */
1003enum interesting tree_entry_interesting(const struct name_entry *entry,
1004 struct strbuf *base, int base_offset,
1005 const struct pathspec *ps)
1006{
1007 enum interesting positive, negative;
1008 positive = do_match(entry, base, base_offset, ps, 0);
1009
1010 /*
1011 * case | entry | positive | negative | result
1012 * -----+-------+----------+----------+-------
1013 * 1 | file | -1 | -1..2 | -1
1014 * 2 | file | 0 | -1..2 | 0
1015 * 3 | file | 1 | -1 | 1
1016 * 4 | file | 1 | 0 | 1
1017 * 5 | file | 1 | 1 | 0
1018 * 6 | file | 1 | 2 | 0
1019 * 7 | file | 2 | -1 | 2
1020 * 8 | file | 2 | 0 | 2
1021 * 9 | file | 2 | 1 | 0
1022 * 10 | file | 2 | 2 | -1
1023 * -----+-------+----------+----------+-------
1024 * 11 | dir | -1 | -1..2 | -1
1025 * 12 | dir | 0 | -1..2 | 0
1026 * 13 | dir | 1 | -1 | 1
1027 * 14 | dir | 1 | 0 | 1
1028 * 15 | dir | 1 | 1 | 1 (*)
1029 * 16 | dir | 1 | 2 | 0
1030 * 17 | dir | 2 | -1 | 2
1031 * 18 | dir | 2 | 0 | 2
1032 * 19 | dir | 2 | 1 | 1 (*)
1033 * 20 | dir | 2 | 2 | -1
1034 *
1035 * (*) An exclude pattern interested in a directory does not
1036 * necessarily mean it will exclude all of the directory. In
1037 * wildcard case, it can't decide until looking at individual
1038 * files inside. So don't write such directories off yet.
1039 */
1040
1041 if (!(ps->magic & PATHSPEC_EXCLUDE) ||
1042 positive <= entry_not_interesting) /* #1, #2, #11, #12 */
1043 return positive;
1044
1045 negative = do_match(entry, base, base_offset, ps, 1);
1046
1047 /* #3, #4, #7, #8, #13, #14, #17, #18 */
1048 if (negative <= entry_not_interesting)
1049 return positive;
1050
1051 /* #15, #19 */
1052 if (S_ISDIR(entry->mode) &&
1053 positive >= entry_interesting &&
1054 negative == entry_interesting)
1055 return entry_interesting;
1056
1057 if ((positive == entry_interesting &&
1058 negative >= entry_interesting) || /* #5, #6, #16 */
1059 (positive == all_entries_interesting &&
1060 negative == entry_interesting)) /* #9 */
1061 return entry_not_interesting;
1062
1063 return all_entries_not_interesting; /* #10, #20 */
1064}