gitweb: Add git_merge sub
[git/gsoc2010-gitweb.git] / sha1_name.c
blobbf924178380c42a50b2fd7a02ff869dcc3ddff6a
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"
8 #include "remote.h"
10 static int find_short_object_filename(int len, const char *name, unsigned char *sha1)
12 struct alternate_object_database *alt;
13 char hex[40];
14 int found = 0;
15 static struct alternate_object_database *fakeent;
17 if (!fakeent) {
18 const char *objdir = get_object_directory();
19 int objdir_len = strlen(objdir);
20 int entlen = objdir_len + 43;
21 fakeent = xmalloc(sizeof(*fakeent) + entlen);
22 memcpy(fakeent->base, objdir, objdir_len);
23 fakeent->name = fakeent->base + objdir_len + 1;
24 fakeent->name[-1] = '/';
26 fakeent->next = alt_odb_list;
28 sprintf(hex, "%.2s", name);
29 for (alt = fakeent; alt && found < 2; alt = alt->next) {
30 struct dirent *de;
31 DIR *dir;
32 sprintf(alt->name, "%.2s/", name);
33 dir = opendir(alt->base);
34 if (!dir)
35 continue;
36 while ((de = readdir(dir)) != NULL) {
37 if (strlen(de->d_name) != 38)
38 continue;
39 if (memcmp(de->d_name, name + 2, len - 2))
40 continue;
41 if (!found) {
42 memcpy(hex + 2, de->d_name, 38);
43 found++;
45 else if (memcmp(hex + 2, de->d_name, 38)) {
46 found = 2;
47 break;
50 closedir(dir);
52 if (found == 1)
53 return get_sha1_hex(hex, sha1) == 0;
54 return found;
57 static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
59 do {
60 if (*a != *b)
61 return 0;
62 a++;
63 b++;
64 len -= 2;
65 } while (len > 1);
66 if (len)
67 if ((*a ^ *b) & 0xf0)
68 return 0;
69 return 1;
72 static int find_short_packed_object(int len, const unsigned char *match, unsigned char *sha1)
74 struct packed_git *p;
75 const unsigned char *found_sha1 = NULL;
76 int found = 0;
78 prepare_packed_git();
79 for (p = packed_git; p && found < 2; p = p->next) {
80 uint32_t num, last;
81 uint32_t first = 0;
82 open_pack_index(p);
83 num = p->num_objects;
84 last = num;
85 while (first < last) {
86 uint32_t mid = (first + last) / 2;
87 const unsigned char *now;
88 int cmp;
90 now = nth_packed_object_sha1(p, mid);
91 cmp = hashcmp(match, now);
92 if (!cmp) {
93 first = mid;
94 break;
96 if (cmp > 0) {
97 first = mid+1;
98 continue;
100 last = mid;
102 if (first < num) {
103 const unsigned char *now, *next;
104 now = nth_packed_object_sha1(p, first);
105 if (match_sha(len, match, now)) {
106 next = nth_packed_object_sha1(p, first+1);
107 if (!next|| !match_sha(len, match, next)) {
108 /* unique within this pack */
109 if (!found) {
110 found_sha1 = now;
111 found++;
113 else if (hashcmp(found_sha1, now)) {
114 found = 2;
115 break;
118 else {
119 /* not even unique within this pack */
120 found = 2;
121 break;
126 if (found == 1)
127 hashcpy(sha1, found_sha1);
128 return found;
131 #define SHORT_NAME_NOT_FOUND (-1)
132 #define SHORT_NAME_AMBIGUOUS (-2)
134 static int find_unique_short_object(int len, char *canonical,
135 unsigned char *res, unsigned char *sha1)
137 int has_unpacked, has_packed;
138 unsigned char unpacked_sha1[20], packed_sha1[20];
140 prepare_alt_odb();
141 has_unpacked = find_short_object_filename(len, canonical, unpacked_sha1);
142 has_packed = find_short_packed_object(len, res, packed_sha1);
143 if (!has_unpacked && !has_packed)
144 return SHORT_NAME_NOT_FOUND;
145 if (1 < has_unpacked || 1 < has_packed)
146 return SHORT_NAME_AMBIGUOUS;
147 if (has_unpacked != has_packed) {
148 hashcpy(sha1, (has_packed ? packed_sha1 : unpacked_sha1));
149 return 0;
151 /* Both have unique ones -- do they match? */
152 if (hashcmp(packed_sha1, unpacked_sha1))
153 return SHORT_NAME_AMBIGUOUS;
154 hashcpy(sha1, packed_sha1);
155 return 0;
158 static int get_short_sha1(const char *name, int len, unsigned char *sha1,
159 int quietly)
161 int i, status;
162 char canonical[40];
163 unsigned char res[20];
165 if (len < MINIMUM_ABBREV || len > 40)
166 return -1;
167 hashclr(res);
168 memset(canonical, 'x', 40);
169 for (i = 0; i < len ;i++) {
170 unsigned char c = name[i];
171 unsigned char val;
172 if (c >= '0' && c <= '9')
173 val = c - '0';
174 else if (c >= 'a' && c <= 'f')
175 val = c - 'a' + 10;
176 else if (c >= 'A' && c <='F') {
177 val = c - 'A' + 10;
178 c -= 'A' - 'a';
180 else
181 return -1;
182 canonical[i] = c;
183 if (!(i & 1))
184 val <<= 4;
185 res[i >> 1] |= val;
188 status = find_unique_short_object(i, canonical, res, sha1);
189 if (!quietly && (status == SHORT_NAME_AMBIGUOUS))
190 return error("short SHA1 %.*s is ambiguous.", len, canonical);
191 return status;
194 const char *find_unique_abbrev(const unsigned char *sha1, int len)
196 int status, exists;
197 static char hex[41];
199 exists = has_sha1_file(sha1);
200 memcpy(hex, sha1_to_hex(sha1), 40);
201 if (len == 40 || !len)
202 return hex;
203 while (len < 40) {
204 unsigned char sha1_ret[20];
205 status = get_short_sha1(hex, len, sha1_ret, 1);
206 if (exists
207 ? !status
208 : status == SHORT_NAME_NOT_FOUND) {
209 hex[len] = 0;
210 return hex;
212 len++;
214 return hex;
217 static int ambiguous_path(const char *path, int len)
219 int slash = 1;
220 int cnt;
222 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;
237 break;
239 return slash;
243 * *string and *len will only be substituted, and *string returned (for
244 * later free()ing) if the string passed in is a magic short-hand form
245 * to name a branch.
247 static char *substitute_branch_name(const char **string, int *len)
249 struct strbuf buf = STRBUF_INIT;
250 int ret = interpret_branch_name(*string, &buf);
252 if (ret == *len) {
253 size_t size;
254 *string = strbuf_detach(&buf, &size);
255 *len = size;
256 return (char *)*string;
259 return NULL;
262 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
264 char *last_branch = substitute_branch_name(&str, &len);
265 const char **p, *r;
266 int refs_found = 0;
268 *ref = NULL;
269 for (p = ref_rev_parse_rules; *p; p++) {
270 char fullref[PATH_MAX];
271 unsigned char sha1_from_ref[20];
272 unsigned char *this_result;
273 int flag;
275 this_result = refs_found ? sha1_from_ref : sha1;
276 mksnpath(fullref, sizeof(fullref), *p, len, str);
277 r = resolve_ref(fullref, this_result, 1, &flag);
278 if (r) {
279 if (!refs_found++)
280 *ref = xstrdup(r);
281 if (!warn_ambiguous_refs)
282 break;
283 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD"))
284 warning("ignoring dangling symref %s.", fullref);
286 free(last_branch);
287 return refs_found;
290 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
292 char *last_branch = substitute_branch_name(&str, &len);
293 const char **p;
294 int logs_found = 0;
296 *log = NULL;
297 for (p = ref_rev_parse_rules; *p; p++) {
298 struct stat st;
299 unsigned char hash[20];
300 char path[PATH_MAX];
301 const char *ref, *it;
303 mksnpath(path, sizeof(path), *p, len, str);
304 ref = resolve_ref(path, hash, 1, NULL);
305 if (!ref)
306 continue;
307 if (!stat(git_path("logs/%s", path), &st) &&
308 S_ISREG(st.st_mode))
309 it = path;
310 else if (strcmp(ref, path) &&
311 !stat(git_path("logs/%s", ref), &st) &&
312 S_ISREG(st.st_mode))
313 it = ref;
314 else
315 continue;
316 if (!logs_found++) {
317 *log = xstrdup(it);
318 hashcpy(sha1, hash);
320 if (!warn_ambiguous_refs)
321 break;
323 free(last_branch);
324 return logs_found;
327 static inline int upstream_mark(const char *string, int len)
329 const char *suffix[] = { "@{upstream}", "@{u}" };
330 int i;
332 for (i = 0; i < ARRAY_SIZE(suffix); i++) {
333 int suffix_len = strlen(suffix[i]);
334 if (suffix_len <= len
335 && !memcmp(string, suffix[i], suffix_len))
336 return suffix_len;
338 return 0;
341 static int get_sha1_1(const char *name, int len, unsigned char *sha1);
343 static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
345 static const char *warning = "warning: refname '%.*s' is ambiguous.\n";
346 char *real_ref = NULL;
347 int refs_found = 0;
348 int at, reflog_len;
350 if (len == 40 && !get_sha1_hex(str, sha1))
351 return 0;
353 /* basic@{time or number or -number} format to query ref-log */
354 reflog_len = at = 0;
355 if (len && str[len-1] == '}') {
356 for (at = len-2; at >= 0; at--) {
357 if (str[at] == '@' && str[at+1] == '{') {
358 if (!upstream_mark(str + at, len - at)) {
359 reflog_len = (len-1) - (at+2);
360 len = at;
362 break;
367 /* Accept only unambiguous ref paths. */
368 if (len && ambiguous_path(str, len))
369 return -1;
371 if (!len && reflog_len) {
372 struct strbuf buf = STRBUF_INIT;
373 int ret;
374 /* try the @{-N} syntax for n-th checkout */
375 ret = interpret_branch_name(str+at, &buf);
376 if (ret > 0) {
377 /* substitute this branch name and restart */
378 return get_sha1_1(buf.buf, buf.len, sha1);
379 } else if (ret == 0) {
380 return -1;
382 /* allow "@{...}" to mean the current branch reflog */
383 refs_found = dwim_ref("HEAD", 4, sha1, &real_ref);
384 } else if (reflog_len)
385 refs_found = dwim_log(str, len, sha1, &real_ref);
386 else
387 refs_found = dwim_ref(str, len, sha1, &real_ref);
389 if (!refs_found)
390 return -1;
392 if (warn_ambiguous_refs && refs_found > 1)
393 fprintf(stderr, warning, len, str);
395 if (reflog_len) {
396 int nth, i;
397 unsigned long at_time;
398 unsigned long co_time;
399 int co_tz, co_cnt;
401 /* a @{-N} placed anywhere except the start is an error */
402 if (str[at+2] == '-')
403 return -1;
405 /* Is it asking for N-th entry, or approxidate? */
406 for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
407 char ch = str[at+2+i];
408 if ('0' <= ch && ch <= '9')
409 nth = nth * 10 + ch - '0';
410 else
411 nth = -1;
413 if (100000000 <= nth) {
414 at_time = nth;
415 nth = -1;
416 } else if (0 <= nth)
417 at_time = 0;
418 else {
419 int errors = 0;
420 char *tmp = xstrndup(str + at + 2, reflog_len);
421 at_time = approxidate_careful(tmp, &errors);
422 free(tmp);
423 if (errors)
424 return -1;
426 if (read_ref_at(real_ref, at_time, nth, sha1, NULL,
427 &co_time, &co_tz, &co_cnt)) {
428 if (at_time)
429 fprintf(stderr,
430 "warning: Log for '%.*s' only goes "
431 "back to %s.\n", len, str,
432 show_date(co_time, co_tz, DATE_RFC2822));
433 else
434 fprintf(stderr,
435 "warning: Log for '%.*s' only has "
436 "%d entries.\n", len, str, co_cnt);
440 free(real_ref);
441 return 0;
444 static int get_parent(const char *name, int len,
445 unsigned char *result, int idx)
447 unsigned char sha1[20];
448 int ret = get_sha1_1(name, len, sha1);
449 struct commit *commit;
450 struct commit_list *p;
452 if (ret)
453 return ret;
454 commit = lookup_commit_reference(sha1);
455 if (!commit)
456 return -1;
457 if (parse_commit(commit))
458 return -1;
459 if (!idx) {
460 hashcpy(result, commit->object.sha1);
461 return 0;
463 p = commit->parents;
464 while (p) {
465 if (!--idx) {
466 hashcpy(result, p->item->object.sha1);
467 return 0;
469 p = p->next;
471 return -1;
474 static int get_nth_ancestor(const char *name, int len,
475 unsigned char *result, int generation)
477 unsigned char sha1[20];
478 struct commit *commit;
479 int ret;
481 ret = get_sha1_1(name, len, sha1);
482 if (ret)
483 return ret;
484 commit = lookup_commit_reference(sha1);
485 if (!commit)
486 return -1;
488 while (generation--) {
489 if (parse_commit(commit) || !commit->parents)
490 return -1;
491 commit = commit->parents->item;
493 hashcpy(result, commit->object.sha1);
494 return 0;
497 struct object *peel_to_type(const char *name, int namelen,
498 struct object *o, enum object_type expected_type)
500 if (name && !namelen)
501 namelen = strlen(name);
502 if (!o) {
503 unsigned char sha1[20];
504 if (get_sha1_1(name, namelen, sha1))
505 return NULL;
506 o = parse_object(sha1);
508 while (1) {
509 if (!o || (!o->parsed && !parse_object(o->sha1)))
510 return NULL;
511 if (o->type == expected_type)
512 return o;
513 if (o->type == OBJ_TAG)
514 o = ((struct tag*) o)->tagged;
515 else if (o->type == OBJ_COMMIT)
516 o = &(((struct commit *) o)->tree->object);
517 else {
518 if (name)
519 error("%.*s: expected %s type, but the object "
520 "dereferences to %s type",
521 namelen, name, typename(expected_type),
522 typename(o->type));
523 return NULL;
528 static int peel_onion(const char *name, int len, unsigned char *sha1)
530 unsigned char outer[20];
531 const char *sp;
532 unsigned int expected_type = 0;
533 struct object *o;
536 * "ref^{type}" dereferences ref repeatedly until you cannot
537 * dereference anymore, or you get an object of given type,
538 * whichever comes first. "ref^{}" means just dereference
539 * tags until you get a non-tag. "ref^0" is a shorthand for
540 * "ref^{commit}". "commit^{tree}" could be used to find the
541 * top-level tree of the given commit.
543 if (len < 4 || name[len-1] != '}')
544 return -1;
546 for (sp = name + len - 1; name <= sp; sp--) {
547 int ch = *sp;
548 if (ch == '{' && name < sp && sp[-1] == '^')
549 break;
551 if (sp <= name)
552 return -1;
554 sp++; /* beginning of type name, or closing brace for empty */
555 if (!strncmp(commit_type, sp, 6) && sp[6] == '}')
556 expected_type = OBJ_COMMIT;
557 else if (!strncmp(tree_type, sp, 4) && sp[4] == '}')
558 expected_type = OBJ_TREE;
559 else if (!strncmp(blob_type, sp, 4) && sp[4] == '}')
560 expected_type = OBJ_BLOB;
561 else if (sp[0] == '}')
562 expected_type = OBJ_NONE;
563 else
564 return -1;
566 if (get_sha1_1(name, sp - name - 2, outer))
567 return -1;
569 o = parse_object(outer);
570 if (!o)
571 return -1;
572 if (!expected_type) {
573 o = deref_tag(o, name, sp - name - 2);
574 if (!o || (!o->parsed && !parse_object(o->sha1)))
575 return -1;
576 hashcpy(sha1, o->sha1);
578 else {
580 * At this point, the syntax look correct, so
581 * if we do not get the needed object, we should
582 * barf.
584 o = peel_to_type(name, len, o, expected_type);
585 if (o) {
586 hashcpy(sha1, o->sha1);
587 return 0;
589 return -1;
591 return 0;
594 static int get_describe_name(const char *name, int len, unsigned char *sha1)
596 const char *cp;
598 for (cp = name + len - 1; name + 2 <= cp; cp--) {
599 char ch = *cp;
600 if (hexval(ch) & ~0377) {
601 /* We must be looking at g in "SOMETHING-g"
602 * for it to be describe output.
604 if (ch == 'g' && cp[-1] == '-') {
605 cp++;
606 len -= cp - name;
607 return get_short_sha1(cp, len, sha1, 1);
611 return -1;
614 static int get_sha1_1(const char *name, int len, unsigned char *sha1)
616 int ret, has_suffix;
617 const char *cp;
620 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
622 has_suffix = 0;
623 for (cp = name + len - 1; name <= cp; cp--) {
624 int ch = *cp;
625 if ('0' <= ch && ch <= '9')
626 continue;
627 if (ch == '~' || ch == '^')
628 has_suffix = ch;
629 break;
632 if (has_suffix) {
633 int num = 0;
634 int len1 = cp - name;
635 cp++;
636 while (cp < name + len)
637 num = num * 10 + *cp++ - '0';
638 if (!num && len1 == len - 1)
639 num = 1;
640 if (has_suffix == '^')
641 return get_parent(name, len1, sha1, num);
642 /* else if (has_suffix == '~') -- goes without saying */
643 return get_nth_ancestor(name, len1, sha1, num);
646 ret = peel_onion(name, len, sha1);
647 if (!ret)
648 return 0;
650 ret = get_sha1_basic(name, len, sha1);
651 if (!ret)
652 return 0;
654 /* It could be describe output that is "SOMETHING-gXXXX" */
655 ret = get_describe_name(name, len, sha1);
656 if (!ret)
657 return 0;
659 return get_short_sha1(name, len, sha1, 0);
662 static int handle_one_ref(const char *path,
663 const unsigned char *sha1, int flag, void *cb_data)
665 struct commit_list **list = cb_data;
666 struct object *object = parse_object(sha1);
667 if (!object)
668 return 0;
669 if (object->type == OBJ_TAG) {
670 object = deref_tag(object, path, strlen(path));
671 if (!object)
672 return 0;
674 if (object->type != OBJ_COMMIT)
675 return 0;
676 insert_by_date((struct commit *)object, list);
677 return 0;
681 * This interprets names like ':/Initial revision of "git"' by searching
682 * through history and returning the first commit whose message starts
683 * with the given string.
685 * For future extension, ':/!' is reserved. If you want to match a message
686 * beginning with a '!', you have to repeat the exclamation mark.
689 #define ONELINE_SEEN (1u<<20)
690 static int get_sha1_oneline(const char *prefix, unsigned char *sha1)
692 struct commit_list *list = NULL, *backup = NULL, *l;
693 int retval = -1;
694 char *temp_commit_buffer = NULL;
696 if (prefix[0] == '!') {
697 if (prefix[1] != '!')
698 die ("Invalid search pattern: %s", prefix);
699 prefix++;
701 for_each_ref(handle_one_ref, &list);
702 for (l = list; l; l = l->next)
703 commit_list_insert(l->item, &backup);
704 while (list) {
705 char *p;
706 struct commit *commit;
707 enum object_type type;
708 unsigned long size;
710 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
711 if (!parse_object(commit->object.sha1))
712 continue;
713 free(temp_commit_buffer);
714 if (commit->buffer)
715 p = commit->buffer;
716 else {
717 p = read_sha1_file(commit->object.sha1, &type, &size);
718 if (!p)
719 continue;
720 temp_commit_buffer = p;
722 if (!(p = strstr(p, "\n\n")))
723 continue;
724 if (!prefixcmp(p + 2, prefix)) {
725 hashcpy(sha1, commit->object.sha1);
726 retval = 0;
727 break;
730 free(temp_commit_buffer);
731 free_commit_list(list);
732 for (l = backup; l; l = l->next)
733 clear_commit_marks(l->item, ONELINE_SEEN);
734 return retval;
737 struct grab_nth_branch_switch_cbdata {
738 long cnt, alloc;
739 struct strbuf *buf;
742 static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
743 const char *email, unsigned long timestamp, int tz,
744 const char *message, void *cb_data)
746 struct grab_nth_branch_switch_cbdata *cb = cb_data;
747 const char *match = NULL, *target = NULL;
748 size_t len;
749 int nth;
751 if (!prefixcmp(message, "checkout: moving from ")) {
752 match = message + strlen("checkout: moving from ");
753 target = strstr(match, " to ");
756 if (!match || !target)
757 return 0;
759 len = target - match;
760 nth = cb->cnt++ % cb->alloc;
761 strbuf_reset(&cb->buf[nth]);
762 strbuf_add(&cb->buf[nth], match, len);
763 return 0;
767 * Parse @{-N} syntax, return the number of characters parsed
768 * if successful; otherwise signal an error with negative value.
770 static int interpret_nth_prior_checkout(const char *name, struct strbuf *buf)
772 long nth;
773 int i, retval;
774 struct grab_nth_branch_switch_cbdata cb;
775 const char *brace;
776 char *num_end;
778 if (name[0] != '@' || name[1] != '{' || name[2] != '-')
779 return -1;
780 brace = strchr(name, '}');
781 if (!brace)
782 return -1;
783 nth = strtol(name+3, &num_end, 10);
784 if (num_end != brace)
785 return -1;
786 if (nth <= 0)
787 return -1;
788 cb.alloc = nth;
789 cb.buf = xmalloc(nth * sizeof(struct strbuf));
790 for (i = 0; i < nth; i++)
791 strbuf_init(&cb.buf[i], 20);
792 cb.cnt = 0;
793 retval = 0;
794 for_each_recent_reflog_ent("HEAD", grab_nth_branch_switch, 40960, &cb);
795 if (cb.cnt < nth) {
796 cb.cnt = 0;
797 for_each_reflog_ent("HEAD", grab_nth_branch_switch, &cb);
799 if (cb.cnt < nth)
800 goto release_return;
801 i = cb.cnt % nth;
802 strbuf_reset(buf);
803 strbuf_add(buf, cb.buf[i].buf, cb.buf[i].len);
804 retval = brace-name+1;
806 release_return:
807 for (i = 0; i < nth; i++)
808 strbuf_release(&cb.buf[i]);
809 free(cb.buf);
811 return retval;
814 int get_sha1_mb(const char *name, unsigned char *sha1)
816 struct commit *one, *two;
817 struct commit_list *mbs;
818 unsigned char sha1_tmp[20];
819 const char *dots;
820 int st;
822 dots = strstr(name, "...");
823 if (!dots)
824 return get_sha1(name, sha1);
825 if (dots == name)
826 st = get_sha1("HEAD", sha1_tmp);
827 else {
828 struct strbuf sb;
829 strbuf_init(&sb, dots - name);
830 strbuf_add(&sb, name, dots - name);
831 st = get_sha1(sb.buf, sha1_tmp);
832 strbuf_release(&sb);
834 if (st)
835 return st;
836 one = lookup_commit_reference_gently(sha1_tmp, 0);
837 if (!one)
838 return -1;
840 if (get_sha1(dots[3] ? (dots + 3) : "HEAD", sha1_tmp))
841 return -1;
842 two = lookup_commit_reference_gently(sha1_tmp, 0);
843 if (!two)
844 return -1;
845 mbs = get_merge_bases(one, two, 1);
846 if (!mbs || mbs->next)
847 st = -1;
848 else {
849 st = 0;
850 hashcpy(sha1, mbs->item->object.sha1);
852 free_commit_list(mbs);
853 return st;
857 * This reads short-hand syntax that not only evaluates to a commit
858 * object name, but also can act as if the end user spelled the name
859 * of the branch from the command line.
861 * - "@{-N}" finds the name of the Nth previous branch we were on, and
862 * places the name of the branch in the given buf and returns the
863 * number of characters parsed if successful.
865 * - "<branch>@{upstream}" finds the name of the other ref that
866 * <branch> is configured to merge with (missing <branch> defaults
867 * to the current branch), and places the name of the branch in the
868 * given buf and returns the number of characters parsed if
869 * successful.
871 * If the input is not of the accepted format, it returns a negative
872 * number to signal an error.
874 * If the input was ok but there are not N branch switches in the
875 * reflog, it returns 0.
877 int interpret_branch_name(const char *name, struct strbuf *buf)
879 char *cp;
880 struct branch *upstream;
881 int namelen = strlen(name);
882 int len = interpret_nth_prior_checkout(name, buf);
883 int tmp_len;
885 if (!len)
886 return len; /* syntax Ok, not enough switches */
887 if (0 < len && len == namelen)
888 return len; /* consumed all */
889 else if (0 < len) {
890 /* we have extra data, which might need further processing */
891 struct strbuf tmp = STRBUF_INIT;
892 int used = buf->len;
893 int ret;
895 strbuf_add(buf, name + len, namelen - len);
896 ret = interpret_branch_name(buf->buf, &tmp);
897 /* that data was not interpreted, remove our cruft */
898 if (ret < 0) {
899 strbuf_setlen(buf, used);
900 return len;
902 strbuf_reset(buf);
903 strbuf_addbuf(buf, &tmp);
904 strbuf_release(&tmp);
905 /* tweak for size of {-N} versus expanded ref name */
906 return ret - used + len;
909 cp = strchr(name, '@');
910 if (!cp)
911 return -1;
912 tmp_len = upstream_mark(cp, namelen - (cp - name));
913 if (!tmp_len)
914 return -1;
915 len = cp + tmp_len - name;
916 cp = xstrndup(name, cp - name);
917 upstream = branch_get(*cp ? cp : NULL);
918 if (!upstream
919 || !upstream->merge
920 || !upstream->merge[0]->dst)
921 return error("No upstream branch found for '%s'", cp);
922 free(cp);
923 cp = shorten_unambiguous_ref(upstream->merge[0]->dst, 0);
924 strbuf_reset(buf);
925 strbuf_addstr(buf, cp);
926 free(cp);
927 return len;
931 * This is like "get_sha1_basic()", except it allows "sha1 expressions",
932 * notably "xyz^" for "parent of xyz"
934 int get_sha1(const char *name, unsigned char *sha1)
936 unsigned unused;
937 return get_sha1_with_mode(name, sha1, &unused);
940 /* Must be called only when object_name:filename doesn't exist. */
941 static void diagnose_invalid_sha1_path(const char *prefix,
942 const char *filename,
943 const unsigned char *tree_sha1,
944 const char *object_name)
946 struct stat st;
947 unsigned char sha1[20];
948 unsigned mode;
950 if (!prefix)
951 prefix = "";
953 if (!lstat(filename, &st))
954 die("Path '%s' exists on disk, but not in '%s'.",
955 filename, object_name);
956 if (errno == ENOENT || errno == ENOTDIR) {
957 char *fullname = xmalloc(strlen(filename)
958 + strlen(prefix) + 1);
959 strcpy(fullname, prefix);
960 strcat(fullname, filename);
962 if (!get_tree_entry(tree_sha1, fullname,
963 sha1, &mode)) {
964 die("Path '%s' exists, but not '%s'.\n"
965 "Did you mean '%s:%s'?",
966 fullname,
967 filename,
968 object_name,
969 fullname);
971 die("Path '%s' does not exist in '%s'",
972 filename, object_name);
976 /* Must be called only when :stage:filename doesn't exist. */
977 static void diagnose_invalid_index_path(int stage,
978 const char *prefix,
979 const char *filename)
981 struct stat st;
982 struct cache_entry *ce;
983 int pos;
984 unsigned namelen = strlen(filename);
985 unsigned fullnamelen;
986 char *fullname;
988 if (!prefix)
989 prefix = "";
991 /* Wrong stage number? */
992 pos = cache_name_pos(filename, namelen);
993 if (pos < 0)
994 pos = -pos - 1;
995 if (pos < active_nr) {
996 ce = active_cache[pos];
997 if (ce_namelen(ce) == namelen &&
998 !memcmp(ce->name, filename, namelen))
999 die("Path '%s' is in the index, but not at stage %d.\n"
1000 "Did you mean ':%d:%s'?",
1001 filename, stage,
1002 ce_stage(ce), filename);
1005 /* Confusion between relative and absolute filenames? */
1006 fullnamelen = namelen + strlen(prefix);
1007 fullname = xmalloc(fullnamelen + 1);
1008 strcpy(fullname, prefix);
1009 strcat(fullname, filename);
1010 pos = cache_name_pos(fullname, fullnamelen);
1011 if (pos < 0)
1012 pos = -pos - 1;
1013 if (pos < active_nr) {
1014 ce = active_cache[pos];
1015 if (ce_namelen(ce) == fullnamelen &&
1016 !memcmp(ce->name, fullname, fullnamelen))
1017 die("Path '%s' is in the index, but not '%s'.\n"
1018 "Did you mean ':%d:%s'?",
1019 fullname, filename,
1020 ce_stage(ce), fullname);
1023 if (!lstat(filename, &st))
1024 die("Path '%s' exists on disk, but not in the index.", filename);
1025 if (errno == ENOENT || errno == ENOTDIR)
1026 die("Path '%s' does not exist (neither on disk nor in the index).",
1027 filename);
1029 free(fullname);
1033 int get_sha1_with_mode_1(const char *name, unsigned char *sha1, unsigned *mode, int gently, const char *prefix)
1035 int ret, bracket_depth;
1036 int namelen = strlen(name);
1037 const char *cp;
1039 *mode = S_IFINVALID;
1040 ret = get_sha1_1(name, namelen, sha1);
1041 if (!ret)
1042 return ret;
1043 /* sha1:path --> object name of path in ent sha1
1044 * :path -> object name of path in index
1045 * :[0-3]:path -> object name of path in index at stage
1047 if (name[0] == ':') {
1048 int stage = 0;
1049 struct cache_entry *ce;
1050 int pos;
1051 if (namelen > 2 && name[1] == '/')
1052 return get_sha1_oneline(name + 2, sha1);
1053 if (namelen < 3 ||
1054 name[2] != ':' ||
1055 name[1] < '0' || '3' < name[1])
1056 cp = name + 1;
1057 else {
1058 stage = name[1] - '0';
1059 cp = name + 3;
1061 namelen = namelen - (cp - name);
1062 if (!active_cache)
1063 read_cache();
1064 pos = cache_name_pos(cp, namelen);
1065 if (pos < 0)
1066 pos = -pos - 1;
1067 while (pos < active_nr) {
1068 ce = active_cache[pos];
1069 if (ce_namelen(ce) != namelen ||
1070 memcmp(ce->name, cp, namelen))
1071 break;
1072 if (ce_stage(ce) == stage) {
1073 hashcpy(sha1, ce->sha1);
1074 *mode = ce->ce_mode;
1075 return 0;
1077 pos++;
1079 if (!gently)
1080 diagnose_invalid_index_path(stage, prefix, cp);
1081 return -1;
1083 for (cp = name, bracket_depth = 0; *cp; cp++) {
1084 if (*cp == '{')
1085 bracket_depth++;
1086 else if (bracket_depth && *cp == '}')
1087 bracket_depth--;
1088 else if (!bracket_depth && *cp == ':')
1089 break;
1091 if (*cp == ':') {
1092 unsigned char tree_sha1[20];
1093 char *object_name = NULL;
1094 if (!gently) {
1095 object_name = xmalloc(cp-name+1);
1096 strncpy(object_name, name, cp-name);
1097 object_name[cp-name] = '\0';
1099 if (!get_sha1_1(name, cp-name, tree_sha1)) {
1100 const char *filename = cp+1;
1101 ret = get_tree_entry(tree_sha1, filename, sha1, mode);
1102 if (!gently) {
1103 diagnose_invalid_sha1_path(prefix, filename,
1104 tree_sha1, object_name);
1105 free(object_name);
1107 return ret;
1108 } else {
1109 if (!gently)
1110 die("Invalid object name '%s'.", object_name);
1113 return ret;