6c9c1c75adefe2d5e38212b75302368293c9137b
1#include "cache.h"
2#include "tag.h"
3#include "commit.h"
4#include "tree.h"
5#include "blob.h"
6#include "tree-walk.h"
7#include "refs.h"
8static int find_short_object_filename(int len, const char *name, unsigned char *sha1)
10{
11 struct alternate_object_database *alt;
12 char hex[40];
13 int found = 0;
14 static struct alternate_object_database *fakeent;
15 if (!fakeent) {
17 const char *objdir = get_object_directory();
18 int objdir_len = strlen(objdir);
19 int entlen = objdir_len + 43;
20 fakeent = xmalloc(sizeof(*fakeent) + entlen);
21 memcpy(fakeent->base, objdir, objdir_len);
22 fakeent->name = fakeent->base + objdir_len + 1;
23 fakeent->name[-1] = '/';
24 }
25 fakeent->next = alt_odb_list;
26 sprintf(hex, "%.2s", name);
28 for (alt = fakeent; alt && found < 2; alt = alt->next) {
29 struct dirent *de;
30 DIR *dir;
31 sprintf(alt->name, "%.2s/", name);
32 dir = opendir(alt->base);
33 if (!dir)
34 continue;
35 while ((de = readdir(dir)) != NULL) {
36 if (strlen(de->d_name) != 38)
37 continue;
38 if (memcmp(de->d_name, name + 2, len - 2))
39 continue;
40 if (!found) {
41 memcpy(hex + 2, de->d_name, 38);
42 found++;
43 }
44 else if (memcmp(hex + 2, de->d_name, 38)) {
45 found = 2;
46 break;
47 }
48 }
49 closedir(dir);
50 }
51 if (found == 1)
52 return get_sha1_hex(hex, sha1) == 0;
53 return found;
54}
55static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
57{
58 do {
59 if (*a != *b)
60 return 0;
61 a++;
62 b++;
63 len -= 2;
64 } while (len > 1);
65 if (len)
66 if ((*a ^ *b) & 0xf0)
67 return 0;
68 return 1;
69}
70static int find_short_packed_object(int len, const unsigned char *match, unsigned char *sha1)
72{
73 struct packed_git *p;
74 const unsigned char *found_sha1 = NULL;
75 int found = 0;
76 prepare_packed_git();
78 for (p = packed_git; p && found < 2; p = p->next) {
79 uint32_t num, last;
80 uint32_t first = 0;
81 open_pack_index(p);
82 num = p->num_objects;
83 last = num;
84 while (first < last) {
85 uint32_t mid = (first + last) / 2;
86 const unsigned char *now;
87 int cmp;
88 now = nth_packed_object_sha1(p, mid);
90 cmp = hashcmp(match, now);
91 if (!cmp) {
92 first = mid;
93 break;
94 }
95 if (cmp > 0) {
96 first = mid+1;
97 continue;
98 }
99 last = mid;
100 }
101 if (first < num) {
102 const unsigned char *now, *next;
103 now = nth_packed_object_sha1(p, first);
104 if (match_sha(len, match, now)) {
105 next = nth_packed_object_sha1(p, first+1);
106 if (!next|| !match_sha(len, match, next)) {
107 /* unique within this pack */
108 if (!found) {
109 found_sha1 = now;
110 found++;
111 }
112 else if (hashcmp(found_sha1, now)) {
113 found = 2;
114 break;
115 }
116 }
117 else {
118 /* not even unique within this pack */
119 found = 2;
120 break;
121 }
122 }
123 }
124 }
125 if (found == 1)
126 hashcpy(sha1, found_sha1);
127 return found;
128}
129#define SHORT_NAME_NOT_FOUND (-1)
131#define SHORT_NAME_AMBIGUOUS (-2)
132static int find_unique_short_object(int len, char *canonical,
134 unsigned char *res, unsigned char *sha1)
135{
136 int has_unpacked, has_packed;
137 unsigned char unpacked_sha1[20], packed_sha1[20];
138 prepare_alt_odb();
140 has_unpacked = find_short_object_filename(len, canonical, unpacked_sha1);
141 has_packed = find_short_packed_object(len, res, packed_sha1);
142 if (!has_unpacked && !has_packed)
143 return SHORT_NAME_NOT_FOUND;
144 if (1 < has_unpacked || 1 < has_packed)
145 return SHORT_NAME_AMBIGUOUS;
146 if (has_unpacked != has_packed) {
147 hashcpy(sha1, (has_packed ? packed_sha1 : unpacked_sha1));
148 return 0;
149 }
150 /* Both have unique ones -- do they match? */
151 if (hashcmp(packed_sha1, unpacked_sha1))
152 return SHORT_NAME_AMBIGUOUS;
153 hashcpy(sha1, packed_sha1);
154 return 0;
155}
156static int get_short_sha1(const char *name, int len, unsigned char *sha1,
158 int quietly)
159{
160 int i, status;
161 char canonical[40];
162 unsigned char res[20];
163 if (len < MINIMUM_ABBREV || len > 40)
165 return -1;
166 hashclr(res);
167 memset(canonical, 'x', 40);
168 for (i = 0; i < len ;i++) {
169 unsigned char c = name[i];
170 unsigned char val;
171 if (c >= '0' && c <= '9')
172 val = c - '0';
173 else if (c >= 'a' && c <= 'f')
174 val = c - 'a' + 10;
175 else if (c >= 'A' && c <='F') {
176 val = c - 'A' + 10;
177 c -= 'A' - 'a';
178 }
179 else
180 return -1;
181 canonical[i] = c;
182 if (!(i & 1))
183 val <<= 4;
184 res[i >> 1] |= val;
185 }
186 status = find_unique_short_object(i, canonical, res, sha1);
188 if (!quietly && (status == SHORT_NAME_AMBIGUOUS))
189 return error("short SHA1 %.*s is ambiguous.", len, canonical);
190 return status;
191}
192const char *find_unique_abbrev(const unsigned char *sha1, int len)
194{
195 int status, is_null;
196 static char hex[41];
197 is_null = is_null_sha1(sha1);
199 memcpy(hex, sha1_to_hex(sha1), 40);
200 if (len == 40 || !len)
201 return hex;
202 while (len < 40) {
203 unsigned char sha1_ret[20];
204 status = get_short_sha1(hex, len, sha1_ret, 1);
205 if (!status ||
206 (is_null && status != SHORT_NAME_AMBIGUOUS)) {
207 hex[len] = 0;
208 return hex;
209 }
210 if (status != SHORT_NAME_AMBIGUOUS)
211 return NULL;
212 len++;
213 }
214 return NULL;
215}
216static int ambiguous_path(const char *path, int len)
218{
219 int slash = 1;
220 int cnt;
221 for (cnt = 0; cnt < len; cnt++) {
223 switch (*path++) {
224 case '\0':
225 break;
226 case '/':
227 if (slash)
228 break;
229 slash = 1;
230 continue;
231 case '.':
232 continue;
233 default:
234 slash = 0;
235 continue;
236 }
237 break;
238 }
239 return slash;
240}
241int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
243{
244 const char **p, *r;
245 int refs_found = 0;
246 *ref = NULL;
248 for (p = ref_rev_parse_rules; *p; p++) {
249 unsigned char sha1_from_ref[20];
250 unsigned char *this_result;
251 this_result = refs_found ? sha1_from_ref : sha1;
253 r = resolve_ref(mkpath(*p, len, str), this_result, 1, NULL);
254 if (r) {
255 if (!refs_found++)
256 *ref = xstrdup(r);
257 if (!warn_ambiguous_refs)
258 break;
259 }
260 }
261 return refs_found;
262}
263int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
265{
266 const char **p;
267 int logs_found = 0;
268 *log = NULL;
270 for (p = ref_rev_parse_rules; *p; p++) {
271 struct stat st;
272 unsigned char hash[20];
273 char path[PATH_MAX];
274 const char *ref, *it;
275 strcpy(path, mkpath(*p, len, str));
277 ref = resolve_ref(path, hash, 0, NULL);
278 if (!ref)
279 continue;
280 if (!stat(git_path("logs/%s", path), &st) &&
281 S_ISREG(st.st_mode))
282 it = path;
283 else if (strcmp(ref, path) &&
284 !stat(git_path("logs/%s", ref), &st) &&
285 S_ISREG(st.st_mode))
286 it = ref;
287 else
288 continue;
289 if (!logs_found++) {
290 *log = xstrdup(it);
291 hashcpy(sha1, hash);
292 }
293 if (!warn_ambiguous_refs)
294 break;
295 }
296 return logs_found;
297}
298static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
300{
301 static const char *warning = "warning: refname '%.*s' is ambiguous.\n";
302 char *real_ref = NULL;
303 int refs_found = 0;
304 int at, reflog_len;
305 if (len == 40 && !get_sha1_hex(str, sha1))
307 return 0;
308 /* basic@{time or number} format to query ref-log */
310 reflog_len = at = 0;
311 if (str[len-1] == '}') {
312 for (at = 0; at < len - 1; at++) {
313 if (str[at] == '@' && str[at+1] == '{') {
314 reflog_len = (len-1) - (at+2);
315 len = at;
316 break;
317 }
318 }
319 }
320 /* Accept only unambiguous ref paths. */
322 if (len && ambiguous_path(str, len))
323 return -1;
324 if (!len && reflog_len) {
326 /* allow "@{...}" to mean the current branch reflog */
327 refs_found = dwim_ref("HEAD", 4, sha1, &real_ref);
328 } else if (reflog_len)
329 refs_found = dwim_log(str, len, sha1, &real_ref);
330 else
331 refs_found = dwim_ref(str, len, sha1, &real_ref);
332 if (!refs_found)
334 return -1;
335 if (warn_ambiguous_refs && refs_found > 1)
337 fprintf(stderr, warning, len, str);
338 if (reflog_len) {
340 int nth, i;
341 unsigned long at_time;
342 unsigned long co_time;
343 int co_tz, co_cnt;
344 /* Is it asking for N-th entry, or approxidate? */
346 for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
347 char ch = str[at+2+i];
348 if ('0' <= ch && ch <= '9')
349 nth = nth * 10 + ch - '0';
350 else
351 nth = -1;
352 }
353 if (0 <= nth)
354 at_time = 0;
355 else
356 at_time = approxidate(str + at + 2);
357 if (read_ref_at(real_ref, at_time, nth, sha1, NULL,
358 &co_time, &co_tz, &co_cnt)) {
359 if (at_time)
360 fprintf(stderr,
361 "warning: Log for '%.*s' only goes "
362 "back to %s.\n", len, str,
363 show_date(co_time, co_tz, DATE_RFC2822));
364 else
365 fprintf(stderr,
366 "warning: Log for '%.*s' only has "
367 "%d entries.\n", len, str, co_cnt);
368 }
369 }
370 free(real_ref);
372 return 0;
373}
374static int get_sha1_1(const char *name, int len, unsigned char *sha1);
376static int get_parent(const char *name, int len,
378 unsigned char *result, int idx)
379{
380 unsigned char sha1[20];
381 int ret = get_sha1_1(name, len, sha1);
382 struct commit *commit;
383 struct commit_list *p;
384 if (ret)
386 return ret;
387 commit = lookup_commit_reference(sha1);
388 if (!commit)
389 return -1;
390 if (parse_commit(commit))
391 return -1;
392 if (!idx) {
393 hashcpy(result, commit->object.sha1);
394 return 0;
395 }
396 p = commit->parents;
397 while (p) {
398 if (!--idx) {
399 hashcpy(result, p->item->object.sha1);
400 return 0;
401 }
402 p = p->next;
403 }
404 return -1;
405}
406static int get_nth_ancestor(const char *name, int len,
408 unsigned char *result, int generation)
409{
410 unsigned char sha1[20];
411 struct commit *commit;
412 int ret;
413 ret = get_sha1_1(name, len, sha1);
415 if (ret)
416 return ret;
417 commit = lookup_commit_reference(sha1);
418 if (!commit)
419 return -1;
420 while (generation--) {
422 if (parse_commit(commit) || !commit->parents)
423 return -1;
424 commit = commit->parents->item;
425 }
426 hashcpy(result, commit->object.sha1);
427 return 0;
428}
429static int peel_onion(const char *name, int len, unsigned char *sha1)
431{
432 unsigned char outer[20];
433 const char *sp;
434 unsigned int expected_type = 0;
435 struct object *o;
436 /*
438 * "ref^{type}" dereferences ref repeatedly until you cannot
439 * dereference anymore, or you get an object of given type,
440 * whichever comes first. "ref^{}" means just dereference
441 * tags until you get a non-tag. "ref^0" is a shorthand for
442 * "ref^{commit}". "commit^{tree}" could be used to find the
443 * top-level tree of the given commit.
444 */
445 if (len < 4 || name[len-1] != '}')
446 return -1;
447 for (sp = name + len - 1; name <= sp; sp--) {
449 int ch = *sp;
450 if (ch == '{' && name < sp && sp[-1] == '^')
451 break;
452 }
453 if (sp <= name)
454 return -1;
455 sp++; /* beginning of type name, or closing brace for empty */
457 if (!strncmp(commit_type, sp, 6) && sp[6] == '}')
458 expected_type = OBJ_COMMIT;
459 else if (!strncmp(tree_type, sp, 4) && sp[4] == '}')
460 expected_type = OBJ_TREE;
461 else if (!strncmp(blob_type, sp, 4) && sp[4] == '}')
462 expected_type = OBJ_BLOB;
463 else if (sp[0] == '}')
464 expected_type = OBJ_NONE;
465 else
466 return -1;
467 if (get_sha1_1(name, sp - name - 2, outer))
469 return -1;
470 o = parse_object(outer);
472 if (!o)
473 return -1;
474 if (!expected_type) {
475 o = deref_tag(o, name, sp - name - 2);
476 if (!o || (!o->parsed && !parse_object(o->sha1)))
477 return -1;
478 hashcpy(sha1, o->sha1);
479 }
480 else {
481 /* At this point, the syntax look correct, so
482 * if we do not get the needed object, we should
483 * barf.
484 */
485 while (1) {
487 if (!o || (!o->parsed && !parse_object(o->sha1)))
488 return -1;
489 if (o->type == expected_type) {
490 hashcpy(sha1, o->sha1);
491 return 0;
492 }
493 if (o->type == OBJ_TAG)
494 o = ((struct tag*) o)->tagged;
495 else if (o->type == OBJ_COMMIT)
496 o = &(((struct commit *) o)->tree->object);
497 else
498 return error("%.*s: expected %s type, but the object dereferences to %s type",
499 len, name, typename(expected_type),
500 typename(o->type));
501 if (!o->parsed)
502 parse_object(o->sha1);
503 }
504 }
505 return 0;
506}
507static int get_describe_name(const char *name, int len, unsigned char *sha1)
509{
510 const char *cp;
511 for (cp = name + len - 1; name + 2 <= cp; cp--) {
513 char ch = *cp;
514 if (hexval(ch) & ~0377) {
515 /* We must be looking at g in "SOMETHING-g"
516 * for it to be describe output.
517 */
518 if (ch == 'g' && cp[-1] == '-') {
519 cp++;
520 len -= cp - name;
521 return get_short_sha1(cp, len, sha1, 1);
522 }
523 }
524 }
525 return -1;
526}
527static int get_sha1_1(const char *name, int len, unsigned char *sha1)
529{
530 int ret, has_suffix;
531 const char *cp;
532 /*
534 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
535 */
536 has_suffix = 0;
537 for (cp = name + len - 1; name <= cp; cp--) {
538 int ch = *cp;
539 if ('0' <= ch && ch <= '9')
540 continue;
541 if (ch == '~' || ch == '^')
542 has_suffix = ch;
543 break;
544 }
545 if (has_suffix) {
547 int num = 0;
548 int len1 = cp - name;
549 cp++;
550 while (cp < name + len)
551 num = num * 10 + *cp++ - '0';
552 if (!num && len1 == len - 1)
553 num = 1;
554 if (has_suffix == '^')
555 return get_parent(name, len1, sha1, num);
556 /* else if (has_suffix == '~') -- goes without saying */
557 return get_nth_ancestor(name, len1, sha1, num);
558 }
559 ret = peel_onion(name, len, sha1);
561 if (!ret)
562 return 0;
563 ret = get_sha1_basic(name, len, sha1);
565 if (!ret)
566 return 0;
567 /* It could be describe output that is "SOMETHING-gXXXX" */
569 ret = get_describe_name(name, len, sha1);
570 if (!ret)
571 return 0;
572 return get_short_sha1(name, len, sha1, 0);
574}
575static int handle_one_ref(const char *path,
577 const unsigned char *sha1, int flag, void *cb_data)
578{
579 struct commit_list **list = cb_data;
580 struct object *object = parse_object(sha1);
581 if (!object)
582 return 0;
583 if (object->type == OBJ_TAG)
584 object = deref_tag(object, path, strlen(path));
585 if (object->type != OBJ_COMMIT)
586 return 0;
587 insert_by_date((struct commit *)object, list);
588 return 0;
589}
590/*
592 * This interprets names like ':/Initial revision of "git"' by searching
593 * through history and returning the first commit whose message starts
594 * with the given string.
595 *
596 * For future extension, ':/!' is reserved. If you want to match a message
597 * beginning with a '!', you have to repeat the exclamation mark.
598 */
599#define ONELINE_SEEN (1u<<20)
601static int get_sha1_oneline(const char *prefix, unsigned char *sha1)
602{
603 struct commit_list *list = NULL, *backup = NULL, *l;
604 int retval = -1;
605 char *temp_commit_buffer = NULL;
606 if (prefix[0] == '!') {
608 if (prefix[1] != '!')
609 die ("Invalid search pattern: %s", prefix);
610 prefix++;
611 }
612 for_each_ref(handle_one_ref, &list);
613 for (l = list; l; l = l->next)
614 commit_list_insert(l->item, &backup);
615 while (list) {
616 char *p;
617 struct commit *commit;
618 enum object_type type;
619 unsigned long size;
620 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
622 parse_object(commit->object.sha1);
623 if (temp_commit_buffer)
624 free(temp_commit_buffer);
625 if (commit->buffer)
626 p = commit->buffer;
627 else {
628 p = read_sha1_file(commit->object.sha1, &type, &size);
629 if (!p)
630 continue;
631 temp_commit_buffer = p;
632 }
633 if (!(p = strstr(p, "\n\n")))
634 continue;
635 if (!prefixcmp(p + 2, prefix)) {
636 hashcpy(sha1, commit->object.sha1);
637 retval = 0;
638 break;
639 }
640 }
641 if (temp_commit_buffer)
642 free(temp_commit_buffer);
643 free_commit_list(list);
644 for (l = backup; l; l = l->next)
645 clear_commit_marks(l->item, ONELINE_SEEN);
646 return retval;
647}
648/*
650 * This is like "get_sha1_basic()", except it allows "sha1 expressions",
651 * notably "xyz^" for "parent of xyz"
652 */
653int get_sha1(const char *name, unsigned char *sha1)
654{
655 unsigned unused;
656 return get_sha1_with_mode(name, sha1, &unused);
657}
658int get_sha1_with_mode(const char *name, unsigned char *sha1, unsigned *mode)
660{
661 int ret, bracket_depth;
662 int namelen = strlen(name);
663 const char *cp;
664 *mode = S_IFINVALID;
666 ret = get_sha1_1(name, namelen, sha1);
667 if (!ret)
668 return ret;
669 /* sha1:path --> object name of path in ent sha1
670 * :path -> object name of path in index
671 * :[0-3]:path -> object name of path in index at stage
672 */
673 if (name[0] == ':') {
674 int stage = 0;
675 struct cache_entry *ce;
676 int pos;
677 if (namelen > 2 && name[1] == '/')
678 return get_sha1_oneline(name + 2, sha1);
679 if (namelen < 3 ||
680 name[2] != ':' ||
681 name[1] < '0' || '3' < name[1])
682 cp = name + 1;
683 else {
684 stage = name[1] - '0';
685 cp = name + 3;
686 }
687 namelen = namelen - (cp - name);
688 if (!active_cache)
689 read_cache();
690 pos = cache_name_pos(cp, namelen);
691 if (pos < 0)
692 pos = -pos - 1;
693 while (pos < active_nr) {
694 ce = active_cache[pos];
695 if (ce_namelen(ce) != namelen ||
696 memcmp(ce->name, cp, namelen))
697 break;
698 if (ce_stage(ce) == stage) {
699 hashcpy(sha1, ce->sha1);
700 *mode = ntohl(ce->ce_mode);
701 return 0;
702 }
703 pos++;
704 }
705 return -1;
706 }
707 for (cp = name, bracket_depth = 0; *cp; cp++) {
708 if (*cp == '{')
709 bracket_depth++;
710 else if (bracket_depth && *cp == '}')
711 bracket_depth--;
712 else if (!bracket_depth && *cp == ':')
713 break;
714 }
715 if (*cp == ':') {
716 unsigned char tree_sha1[20];
717 if (!get_sha1_1(name, cp-name, tree_sha1))
718 return get_tree_entry(tree_sha1, cp+1, sha1,
719 mode);
720 }
721 return ret;
722}