Git 1.7.6
[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"
1b0c7174 6
4651ece8
LT
7static const char *get_mode(const char *str, unsigned int *modep)
8{
9 unsigned char c;
10 unsigned int mode = 0;
11
64cc1c09
MK
12 if (*str == ' ')
13 return NULL;
14
4651ece8
LT
15 while ((c = *str++) != ' ') {
16 if (c < '0' || c > '7')
17 return NULL;
18 mode = (mode << 3) + (c - '0');
19 }
20 *modep = mode;
21 return str;
22}
23
64cc1c09 24static void decode_tree_entry(struct tree_desc *desc, const char *buf, unsigned long size)
4651ece8
LT
25{
26 const char *path;
27 unsigned int mode, len;
28
64cc1c09
MK
29 if (size < 24 || buf[size - 21])
30 die("corrupt tree file");
31
4651ece8 32 path = get_mode(buf, &mode);
64cc1c09 33 if (!path || !*path)
4651ece8
LT
34 die("corrupt tree file");
35 len = strlen(path) + 1;
36
37 /* Initialize the descriptor entry */
38 desc->entry.path = path;
39 desc->entry.mode = mode;
40 desc->entry.sha1 = (const unsigned char *)(path + len);
41}
42
6fda5e51
LT
43void init_tree_desc(struct tree_desc *desc, const void *buffer, unsigned long size)
44{
45 desc->buffer = buffer;
46 desc->size = size;
4651ece8
LT
47 if (size)
48 decode_tree_entry(desc, buffer, size);
6fda5e51
LT
49}
50
1b0c7174
JH
51void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1)
52{
53 unsigned long size = 0;
54 void *buf = NULL;
55
56 if (sha1) {
8e440259 57 buf = read_object_with_reference(sha1, tree_type, &size, NULL);
1b0c7174
JH
58 if (!buf)
59 die("unable to read tree %s", sha1_to_hex(sha1));
60 }
6fda5e51 61 init_tree_desc(desc, buf, size);
1b0c7174
JH
62 return buf;
63}
64
1b0c7174
JH
65static void entry_clear(struct name_entry *a)
66{
67 memset(a, 0, sizeof(*a));
68}
69
70static void entry_extract(struct tree_desc *t, struct name_entry *a)
71{
4651ece8 72 *a = t->entry;
1b0c7174
JH
73}
74
75void update_tree_entry(struct tree_desc *desc)
76{
6fda5e51 77 const void *buf = desc->buffer;
4651ece8 78 const unsigned char *end = desc->entry.sha1 + 20;
1b0c7174 79 unsigned long size = desc->size;
4651ece8 80 unsigned long len = end - (const unsigned char *)buf;
1b0c7174
JH
81
82 if (size < len)
83 die("corrupt tree file");
4651ece8
LT
84 buf = end;
85 size -= len;
86 desc->buffer = buf;
87 desc->size = size;
88 if (size)
89 decode_tree_entry(desc, buf, size);
1b0c7174
JH
90}
91
4c068a98
LT
92int tree_entry(struct tree_desc *desc, struct name_entry *entry)
93{
4651ece8 94 if (!desc->size)
4c068a98
LT
95 return 0;
96
4651ece8
LT
97 *entry = desc->entry;
98 update_tree_entry(desc);
4c068a98
LT
99 return 1;
100}
101
40d934df
LT
102void setup_traverse_info(struct traverse_info *info, const char *base)
103{
104 int pathlen = strlen(base);
bcbe5a51 105 static struct traverse_info dummy;
40d934df
LT
106
107 memset(info, 0, sizeof(*info));
108 if (pathlen && base[pathlen-1] == '/')
109 pathlen--;
110 info->pathlen = pathlen ? pathlen + 1 : 0;
111 info->name.path = base;
112 info->name.sha1 = (void *)(base + pathlen + 1);
bcbe5a51
LT
113 if (pathlen)
114 info->prev = &dummy;
40d934df
LT
115}
116
117char *make_traverse_path(char *path, const struct traverse_info *info, const struct name_entry *n)
118{
119 int len = tree_entry_len(n->path, n->sha1);
120 int pathlen = info->pathlen;
121
122 path[pathlen + len] = 0;
123 for (;;) {
124 memcpy(path + pathlen, n->path, len);
125 if (!pathlen)
126 break;
127 path[--pathlen] = '/';
128 n = &info->name;
129 len = tree_entry_len(n->path, n->sha1);
130 info = info->prev;
131 pathlen -= len;
132 }
133 return path;
134}
135
1ee26571
JH
136struct tree_desc_skip {
137 struct tree_desc_skip *prev;
138 const void *ptr;
139};
140
141struct tree_desc_x {
142 struct tree_desc d;
143 struct tree_desc_skip *skip;
144};
145
146static int name_compare(const char *a, int a_len,
147 const char *b, int b_len)
148{
149 int len = (a_len < b_len) ? a_len : b_len;
150 int cmp = memcmp(a, b, len);
151 if (cmp)
152 return cmp;
153 return (a_len - b_len);
154}
155
156static int check_entry_match(const char *a, int a_len, const char *b, int b_len)
157{
158 /*
159 * The caller wants to pick *a* from a tree or nothing.
160 * We are looking at *b* in a tree.
161 *
162 * (0) If a and b are the same name, we are trivially happy.
163 *
164 * There are three possibilities where *a* could be hiding
165 * behind *b*.
166 *
167 * (1) *a* == "t", *b* == "ab" i.e. *b* sorts earlier than *a* no
168 * matter what.
169 * (2) *a* == "t", *b* == "t-2" and "t" is a subtree in the tree;
170 * (3) *a* == "t-2", *b* == "t" and "t-2" is a blob in the tree.
171 *
172 * Otherwise we know *a* won't appear in the tree without
173 * scanning further.
174 */
175
176 int cmp = name_compare(a, a_len, b, b_len);
177
178 /* Most common case first -- reading sync'd trees */
179 if (!cmp)
180 return cmp;
181
182 if (0 < cmp) {
183 /* a comes after b; it does not matter if it is case (3)
184 if (b_len < a_len && !memcmp(a, b, b_len) && a[b_len] < '/')
185 return 1;
186 */
187 return 1; /* keep looking */
188 }
189
190 /* b comes after a; are we looking at case (2)? */
191 if (a_len < b_len && !memcmp(a, b, a_len) && b[a_len] < '/')
192 return 1; /* keep looking */
193
194 return -1; /* a cannot appear in the tree */
195}
196
197/*
198 * From the extended tree_desc, extract the first name entry, while
199 * paying attention to the candidate "first" name. Most importantly,
200 * when looking for an entry, if there are entries that sorts earlier
201 * in the tree object representation than that name, skip them and
202 * process the named entry first. We will remember that we haven't
203 * processed the first entry yet, and in the later call skip the
204 * entry we processed early when update_extended_entry() is called.
205 *
206 * E.g. if the underlying tree object has these entries:
207 *
208 * blob "t-1"
209 * blob "t-2"
210 * tree "t"
211 * blob "t=1"
212 *
213 * and the "first" asks for "t", remember that we still need to
214 * process "t-1" and "t-2" but extract "t". After processing the
215 * entry "t" from this call, the caller will let us know by calling
216 * update_extended_entry() that we can remember "t" has been processed
217 * already.
218 */
219
220static void extended_entry_extract(struct tree_desc_x *t,
221 struct name_entry *a,
222 const char *first,
223 int first_len)
224{
225 const char *path;
226 int len;
227 struct tree_desc probe;
228 struct tree_desc_skip *skip;
229
230 /*
231 * Extract the first entry from the tree_desc, but skip the
232 * ones that we already returned in earlier rounds.
233 */
234 while (1) {
235 if (!t->d.size) {
236 entry_clear(a);
237 break; /* not found */
238 }
239 entry_extract(&t->d, a);
240 for (skip = t->skip; skip; skip = skip->prev)
241 if (a->path == skip->ptr)
242 break; /* found */
243 if (!skip)
244 break;
245 /* We have processed this entry already. */
246 update_tree_entry(&t->d);
247 }
248
249 if (!first || !a->path)
250 return;
251
252 /*
253 * The caller wants "first" from this tree, or nothing.
254 */
255 path = a->path;
256 len = tree_entry_len(a->path, a->sha1);
257 switch (check_entry_match(first, first_len, path, len)) {
258 case -1:
259 entry_clear(a);
260 case 0:
261 return;
262 default:
263 break;
264 }
265
266 /*
267 * We need to look-ahead -- we suspect that a subtree whose
268 * name is "first" may be hiding behind the current entry "path".
269 */
270 probe = t->d;
271 while (probe.size) {
272 entry_extract(&probe, a);
273 path = a->path;
274 len = tree_entry_len(a->path, a->sha1);
275 switch (check_entry_match(first, first_len, path, len)) {
276 case -1:
277 entry_clear(a);
278 case 0:
279 return;
280 default:
281 update_tree_entry(&probe);
282 break;
283 }
284 /* keep looking */
285 }
286 entry_clear(a);
287}
288
289static void update_extended_entry(struct tree_desc_x *t, struct name_entry *a)
290{
291 if (t->d.entry.path == a->path) {
292 update_tree_entry(&t->d);
293 } else {
294 /* we have returned this entry early */
295 struct tree_desc_skip *skip = xmalloc(sizeof(*skip));
296 skip->ptr = a->path;
297 skip->prev = t->skip;
298 t->skip = skip;
299 }
300}
301
302static void free_extended_entry(struct tree_desc_x *t)
303{
304 struct tree_desc_skip *p, *s;
305
306 for (s = t->skip; s; s = p) {
307 p = s->prev;
308 free(s);
309 }
310}
311
5803c6f8 312int traverse_trees(int n, struct tree_desc *t, struct traverse_info *info)
1b0c7174 313{
5803c6f8 314 int ret = 0;
e6c111b4 315 int error = 0;
1b0c7174 316 struct name_entry *entry = xmalloc(n*sizeof(*entry));
1ee26571
JH
317 int i;
318 struct tree_desc_x *tx = xcalloc(n, sizeof(*tx));
319
320 for (i = 0; i < n; i++)
321 tx[i].d = t[i];
1b0c7174
JH
322
323 for (;;) {
1ee26571
JH
324 unsigned long mask, dirmask;
325 const char *first = NULL;
326 int first_len = 0;
327 struct name_entry *e;
328 int len;
329
330 for (i = 0; i < n; i++) {
331 e = entry + i;
332 extended_entry_extract(tx + i, e, NULL, 0);
333 }
1b0c7174 334
1ee26571
JH
335 /*
336 * A tree may have "t-2" at the current location even
337 * though it may have "t" that is a subtree behind it,
338 * and another tree may return "t". We want to grab
339 * all "t" from all trees to match in such a case.
340 */
1b0c7174 341 for (i = 0; i < n; i++) {
1ee26571
JH
342 e = entry + i;
343 if (!e->path)
1b0c7174 344 continue;
1ee26571
JH
345 len = tree_entry_len(e->path, e->sha1);
346 if (!first) {
347 first = e->path;
348 first_len = len;
349 continue;
350 }
351 if (name_compare(e->path, len, first, first_len) < 0) {
352 first = e->path;
353 first_len = len;
354 }
355 }
356
357 if (first) {
358 for (i = 0; i < n; i++) {
359 e = entry + i;
360 extended_entry_extract(tx + i, e, first, first_len);
361 /* Cull the ones that are not the earliest */
362 if (!e->path)
1b0c7174 363 continue;
1ee26571
JH
364 len = tree_entry_len(e->path, e->sha1);
365 if (name_compare(e->path, len, first, first_len))
366 entry_clear(e);
1b0c7174 367 }
1ee26571
JH
368 }
369
370 /* Now we have in entry[i] the earliest name from the trees */
371 mask = 0;
372 dirmask = 0;
373 for (i = 0; i < n; i++) {
374 if (!entry[i].path)
375 continue;
1b0c7174 376 mask |= 1ul << i;
91e4f036
LT
377 if (S_ISDIR(entry[i].mode))
378 dirmask |= 1ul << i;
1b0c7174
JH
379 }
380 if (!mask)
381 break;
91e4f036 382 ret = info->fn(n, mask, dirmask, entry, info);
e6c111b4
MM
383 if (ret < 0) {
384 error = ret;
385 if (!info->show_all_errors)
386 break;
387 }
1ee26571 388 mask &= ret;
5803c6f8 389 ret = 0;
1ee26571 390 for (i = 0; i < n; i++)
5803c6f8 391 if (mask & (1ul << i))
1ee26571 392 update_extended_entry(tx + i, entry + i);
1b0c7174
JH
393 }
394 free(entry);
1ee26571
JH
395 for (i = 0; i < n; i++)
396 free_extended_entry(tx + i);
397 free(tx);
e6c111b4 398 return error;
1b0c7174
JH
399}
400
4dcff634
JH
401static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char *result, unsigned *mode)
402{
403 int namelen = strlen(name);
404 while (t->size) {
405 const char *entry;
406 const unsigned char *sha1;
407 int entrylen, cmp;
408
409 sha1 = tree_entry_extract(t, &entry, mode);
410 update_tree_entry(t);
304de2d2 411 entrylen = tree_entry_len(entry, sha1);
4dcff634
JH
412 if (entrylen > namelen)
413 continue;
414 cmp = memcmp(name, entry, entrylen);
415 if (cmp > 0)
416 continue;
417 if (cmp < 0)
418 break;
419 if (entrylen == namelen) {
e702496e 420 hashcpy(result, sha1);
4dcff634
JH
421 return 0;
422 }
423 if (name[entrylen] != '/')
424 continue;
425 if (!S_ISDIR(*mode))
426 break;
427 if (++entrylen == namelen) {
e702496e 428 hashcpy(result, sha1);
4dcff634
JH
429 return 0;
430 }
431 return get_tree_entry(sha1, name + entrylen, result, mode);
432 }
433 return -1;
434}
435
436int get_tree_entry(const unsigned char *tree_sha1, const char *name, unsigned char *sha1, unsigned *mode)
437{
438 int retval;
439 void *tree;
6fda5e51 440 unsigned long size;
4dcff634 441 struct tree_desc t;
d93b7d1c 442 unsigned char root[20];
4dcff634 443
6fda5e51 444 tree = read_object_with_reference(tree_sha1, tree_type, &size, root);
4dcff634
JH
445 if (!tree)
446 return -1;
d93b7d1c
JK
447
448 if (name[0] == '\0') {
449 hashcpy(sha1, root);
ef006503 450 free(tree);
d93b7d1c
JK
451 return 0;
452 }
453
6fda5e51 454 init_tree_desc(&t, tree, size);
4dcff634
JH
455 retval = find_tree_entry(&t, name, sha1, mode);
456 free(tree);
457 return retval;
458}
2c389fc8 459
58c4d666
NTND
460static int match_entry(const struct name_entry *entry, int pathlen,
461 const char *match, int matchlen,
462 int *never_interesting)
463{
464 int m = -1; /* signals that we haven't called strncmp() */
465
466 if (*never_interesting) {
467 /*
468 * We have not seen any match that sorts later
469 * than the current path.
470 */
471
472 /*
473 * Does match sort strictly earlier than path
474 * with their common parts?
475 */
476 m = strncmp(match, entry->path,
477 (matchlen < pathlen) ? matchlen : pathlen);
478 if (m < 0)
479 return 0;
480
481 /*
482 * If we come here even once, that means there is at
483 * least one pathspec that would sort equal to or
484 * later than the path we are currently looking at.
485 * In other words, if we have never reached this point
486 * after iterating all pathspecs, it means all
487 * pathspecs are either outside of base, or inside the
488 * base but sorts strictly earlier than the current
489 * one. In either case, they will never match the
490 * subsequent entries. In such a case, we initialized
491 * the variable to -1 and that is what will be
492 * returned, allowing the caller to terminate early.
493 */
494 *never_interesting = 0;
495 }
496
497 if (pathlen > matchlen)
498 return 0;
499
500 if (matchlen > pathlen) {
501 if (match[pathlen] != '/')
502 return 0;
503 if (!S_ISDIR(entry->mode))
504 return 0;
505 }
506
507 if (m == -1)
508 /*
509 * we cheated and did not do strncmp(), so we do
510 * that here.
511 */
512 m = strncmp(match, entry->path, pathlen);
513
514 /*
515 * If common part matched earlier then it is a hit,
516 * because we rejected the case where path is not a
517 * leading directory and is shorter than match.
518 */
519 if (!m)
520 return 1;
521
522 return 0;
523}
524
525static int match_dir_prefix(const char *base, int baselen,
526 const char *match, int matchlen)
527{
528 if (strncmp(base, match, matchlen))
529 return 0;
530
531 /*
532 * If the base is a subdirectory of a path which
533 * was specified, all of them are interesting.
534 */
535 if (!matchlen ||
536 base[matchlen] == '/' ||
537 match[matchlen - 1] == '/')
538 return 1;
539
540 /* Just a random prefix match */
541 return 0;
542}
543
2c389fc8
NTND
544/*
545 * Is a tree entry interesting given the pathspec we have?
546 *
1376e507
NTND
547 * Pre-condition: either baselen == base_offset (i.e. empty path)
548 * or base[baselen-1] == '/' (i.e. with trailing slash).
2c389fc8
NTND
549 *
550 * Return:
551 * - 2 for "yes, and all subsequent entries will be"
552 * - 1 for yes
553 * - zero for no
554 * - negative for "no, and no subsequent entries will be either"
555 */
556int tree_entry_interesting(const struct name_entry *entry,
1376e507 557 struct strbuf *base, int base_offset,
2c389fc8
NTND
558 const struct pathspec *ps)
559{
560 int i;
1376e507 561 int pathlen, baselen = base->len - base_offset;
d38f2809 562 int never_interesting = ps->has_wildcard ? 0 : -1;
2c389fc8 563
bc96cc87
NTND
564 if (!ps->nr) {
565 if (!ps->recursive || ps->max_depth == -1)
566 return 2;
1376e507 567 return !!within_depth(base->buf + base_offset, baselen,
bc96cc87
NTND
568 !!S_ISDIR(entry->mode),
569 ps->max_depth);
570 }
2c389fc8
NTND
571
572 pathlen = tree_entry_len(entry->path, entry->sha1);
573
1376e507 574 for (i = ps->nr - 1; i >= 0; i--) {
2c389fc8
NTND
575 const struct pathspec_item *item = ps->items+i;
576 const char *match = item->match;
1376e507 577 const char *base_str = base->buf + base_offset;
2c389fc8 578 int matchlen = item->len;
2c389fc8
NTND
579
580 if (baselen >= matchlen) {
581 /* If it doesn't match, move along... */
1376e507 582 if (!match_dir_prefix(base_str, baselen, match, matchlen))
d38f2809 583 goto match_wildcards;
bc96cc87
NTND
584
585 if (!ps->recursive || ps->max_depth == -1)
586 return 2;
587
1376e507 588 return !!within_depth(base_str + matchlen + 1,
bc96cc87
NTND
589 baselen - matchlen - 1,
590 !!S_ISDIR(entry->mode),
591 ps->max_depth);
2c389fc8
NTND
592 }
593
594 /* Does the base match? */
1376e507 595 if (!strncmp(base_str, match, baselen)) {
58c4d666
NTND
596 if (match_entry(entry, pathlen,
597 match + baselen, matchlen - baselen,
598 &never_interesting))
599 return 1;
f1a2ddbb 600
33e0f62b 601 if (ps->items[i].use_wildcard) {
f1a2ddbb
NTND
602 if (!fnmatch(match + baselen, entry->path, 0))
603 return 1;
604
605 /*
606 * Match all directories. We'll try to
607 * match files later on.
608 */
609 if (ps->recursive && S_ISDIR(entry->mode))
610 return 1;
611 }
612
613 continue;
2c389fc8 614 }
d38f2809
NTND
615
616match_wildcards:
33e0f62b 617 if (!ps->items[i].use_wildcard)
d38f2809
NTND
618 continue;
619
620 /*
621 * Concatenate base and entry->path into one and do
622 * fnmatch() on it.
623 */
624
625 strbuf_add(base, entry->path, pathlen);
626
1376e507
NTND
627 if (!fnmatch(match, base->buf + base_offset, 0)) {
628 strbuf_setlen(base, base_offset + baselen);
d38f2809
NTND
629 return 1;
630 }
1376e507 631 strbuf_setlen(base, base_offset + baselen);
d38f2809
NTND
632
633 /*
634 * Match all directories. We'll try to match files
635 * later on.
636 */
637 if (ps->recursive && S_ISDIR(entry->mode))
638 return 1;
2c389fc8
NTND
639 }
640 return never_interesting; /* No matches */
641}