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Commit | Line | Data |
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9938af6a | 1 | #include "cache.h" |
5385f52d | 2 | #include "tag.h" |
9938af6a | 3 | #include "commit.h" |
5385f52d JH |
4 | #include "tree.h" |
5 | #include "blob.h" | |
9938af6a JH |
6 | |
7 | static int find_short_object_filename(int len, const char *name, unsigned char *sha1) | |
8 | { | |
99a19b43 | 9 | struct alternate_object_database *alt; |
9938af6a | 10 | char hex[40]; |
99a19b43 JH |
11 | int found = 0; |
12 | static struct alternate_object_database *fakeent; | |
13 | ||
14 | if (!fakeent) { | |
15 | const char *objdir = get_object_directory(); | |
16 | int objdir_len = strlen(objdir); | |
17 | int entlen = objdir_len + 43; | |
18 | fakeent = xmalloc(sizeof(*fakeent) + entlen); | |
19 | memcpy(fakeent->base, objdir, objdir_len); | |
20 | fakeent->name = fakeent->base + objdir_len + 1; | |
21 | fakeent->name[-1] = '/'; | |
22 | } | |
23 | fakeent->next = alt_odb_list; | |
9938af6a | 24 | |
9938af6a | 25 | sprintf(hex, "%.2s", name); |
99a19b43 | 26 | for (alt = fakeent; alt && found < 2; alt = alt->next) { |
9938af6a | 27 | struct dirent *de; |
99a19b43 JH |
28 | DIR *dir; |
29 | sprintf(alt->name, "%.2s/", name); | |
30 | dir = opendir(alt->base); | |
31 | if (!dir) | |
32 | continue; | |
9938af6a JH |
33 | while ((de = readdir(dir)) != NULL) { |
34 | if (strlen(de->d_name) != 38) | |
35 | continue; | |
99a19b43 | 36 | if (memcmp(de->d_name, name + 2, len - 2)) |
9938af6a | 37 | continue; |
99a19b43 JH |
38 | if (!found) { |
39 | memcpy(hex + 2, de->d_name, 38); | |
40 | found++; | |
41 | } | |
42 | else if (memcmp(hex + 2, de->d_name, 38)) { | |
43 | found = 2; | |
9938af6a | 44 | break; |
99a19b43 | 45 | } |
9938af6a JH |
46 | } |
47 | closedir(dir); | |
48 | } | |
49 | if (found == 1) | |
50 | return get_sha1_hex(hex, sha1) == 0; | |
99a19b43 | 51 | return found; |
9938af6a JH |
52 | } |
53 | ||
54 | static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b) | |
55 | { | |
56 | do { | |
57 | if (*a != *b) | |
58 | return 0; | |
59 | a++; | |
60 | b++; | |
61 | len -= 2; | |
62 | } while (len > 1); | |
63 | if (len) | |
64 | if ((*a ^ *b) & 0xf0) | |
65 | return 0; | |
66 | return 1; | |
67 | } | |
68 | ||
69 | static int find_short_packed_object(int len, const unsigned char *match, unsigned char *sha1) | |
70 | { | |
71 | struct packed_git *p; | |
99a19b43 JH |
72 | unsigned char found_sha1[20]; |
73 | int found = 0; | |
9938af6a JH |
74 | |
75 | prepare_packed_git(); | |
99a19b43 | 76 | for (p = packed_git; p && found < 2; p = p->next) { |
9938af6a JH |
77 | unsigned num = num_packed_objects(p); |
78 | unsigned first = 0, last = num; | |
79 | while (first < last) { | |
80 | unsigned mid = (first + last) / 2; | |
81 | unsigned char now[20]; | |
82 | int cmp; | |
83 | ||
84 | nth_packed_object_sha1(p, mid, now); | |
85 | cmp = memcmp(match, now, 20); | |
86 | if (!cmp) { | |
87 | first = mid; | |
88 | break; | |
89 | } | |
90 | if (cmp > 0) { | |
91 | first = mid+1; | |
92 | continue; | |
93 | } | |
94 | last = mid; | |
95 | } | |
96 | if (first < num) { | |
0bc45890 | 97 | unsigned char now[20], next[20]; |
9938af6a JH |
98 | nth_packed_object_sha1(p, first, now); |
99 | if (match_sha(len, match, now)) { | |
0bc45890 JH |
100 | if (nth_packed_object_sha1(p, first+1, next) || |
101 | !match_sha(len, match, next)) { | |
102 | /* unique within this pack */ | |
103 | if (!found) { | |
104 | memcpy(found_sha1, now, 20); | |
105 | found++; | |
106 | } | |
107 | else if (memcmp(found_sha1, now, 20)) { | |
108 | found = 2; | |
109 | break; | |
110 | } | |
99a19b43 | 111 | } |
0bc45890 JH |
112 | else { |
113 | /* not even unique within this pack */ | |
99a19b43 JH |
114 | found = 2; |
115 | break; | |
9938af6a JH |
116 | } |
117 | } | |
118 | } | |
119 | } | |
99a19b43 JH |
120 | if (found == 1) |
121 | memcpy(sha1, found_sha1, 20); | |
122 | return found; | |
123 | } | |
124 | ||
013f276e JH |
125 | #define SHORT_NAME_NOT_FOUND (-1) |
126 | #define SHORT_NAME_AMBIGUOUS (-2) | |
127 | ||
99a19b43 JH |
128 | static int find_unique_short_object(int len, char *canonical, |
129 | unsigned char *res, unsigned char *sha1) | |
130 | { | |
131 | int has_unpacked, has_packed; | |
132 | unsigned char unpacked_sha1[20], packed_sha1[20]; | |
133 | ||
134 | has_unpacked = find_short_object_filename(len, canonical, unpacked_sha1); | |
135 | has_packed = find_short_packed_object(len, res, packed_sha1); | |
136 | if (!has_unpacked && !has_packed) | |
013f276e | 137 | return SHORT_NAME_NOT_FOUND; |
99a19b43 | 138 | if (1 < has_unpacked || 1 < has_packed) |
013f276e | 139 | return SHORT_NAME_AMBIGUOUS; |
99a19b43 JH |
140 | if (has_unpacked != has_packed) { |
141 | memcpy(sha1, (has_packed ? packed_sha1 : unpacked_sha1), 20); | |
142 | return 0; | |
143 | } | |
144 | /* Both have unique ones -- do they match? */ | |
145 | if (memcmp(packed_sha1, unpacked_sha1, 20)) | |
013f276e | 146 | return -2; |
99a19b43 | 147 | memcpy(sha1, packed_sha1, 20); |
9938af6a JH |
148 | return 0; |
149 | } | |
150 | ||
013f276e JH |
151 | static int get_short_sha1(const char *name, int len, unsigned char *sha1, |
152 | int quietly) | |
9938af6a | 153 | { |
013f276e | 154 | int i, status; |
9938af6a JH |
155 | char canonical[40]; |
156 | unsigned char res[20]; | |
157 | ||
af61c6e0 LT |
158 | if (len < 4) |
159 | return -1; | |
9938af6a JH |
160 | memset(res, 0, 20); |
161 | memset(canonical, 'x', 40); | |
af61c6e0 | 162 | for (i = 0; i < len ;i++) { |
9938af6a JH |
163 | unsigned char c = name[i]; |
164 | unsigned char val; | |
9938af6a JH |
165 | if (c >= '0' && c <= '9') |
166 | val = c - '0'; | |
167 | else if (c >= 'a' && c <= 'f') | |
168 | val = c - 'a' + 10; | |
169 | else if (c >= 'A' && c <='F') { | |
170 | val = c - 'A' + 10; | |
171 | c -= 'A' - 'a'; | |
172 | } | |
173 | else | |
174 | return -1; | |
175 | canonical[i] = c; | |
176 | if (!(i & 1)) | |
177 | val <<= 4; | |
178 | res[i >> 1] |= val; | |
179 | } | |
99a19b43 | 180 | |
013f276e JH |
181 | status = find_unique_short_object(i, canonical, res, sha1); |
182 | if (!quietly && (status == SHORT_NAME_AMBIGUOUS)) | |
183 | return error("short SHA1 %.*s is ambiguous.", len, canonical); | |
184 | return status; | |
185 | } | |
186 | ||
187 | const char *find_unique_abbrev(const unsigned char *sha1, int len) | |
188 | { | |
189 | int status; | |
190 | static char hex[41]; | |
191 | memcpy(hex, sha1_to_hex(sha1), 40); | |
192 | while (len < 40) { | |
193 | unsigned char sha1_ret[20]; | |
194 | status = get_short_sha1(hex, len, sha1_ret, 1); | |
195 | if (!status) { | |
196 | hex[len] = 0; | |
197 | return hex; | |
198 | } | |
199 | if (status != SHORT_NAME_AMBIGUOUS) | |
200 | return NULL; | |
201 | len++; | |
202 | } | |
203 | return NULL; | |
9938af6a JH |
204 | } |
205 | ||
6677c466 | 206 | static int ambiguous_path(const char *path, int len) |
af13cdf2 LT |
207 | { |
208 | int slash = 1; | |
6677c466 | 209 | int cnt; |
af13cdf2 | 210 | |
6677c466 | 211 | for (cnt = 0; cnt < len; cnt++) { |
af13cdf2 LT |
212 | switch (*path++) { |
213 | case '\0': | |
214 | break; | |
215 | case '/': | |
216 | if (slash) | |
217 | break; | |
218 | slash = 1; | |
219 | continue; | |
220 | case '.': | |
221 | continue; | |
222 | default: | |
223 | slash = 0; | |
224 | continue; | |
225 | } | |
c054d64e | 226 | break; |
af13cdf2 | 227 | } |
6677c466 | 228 | return slash; |
af13cdf2 LT |
229 | } |
230 | ||
9938af6a JH |
231 | static int get_sha1_basic(const char *str, int len, unsigned char *sha1) |
232 | { | |
233 | static const char *prefix[] = { | |
234 | "", | |
235 | "refs", | |
236 | "refs/tags", | |
237 | "refs/heads", | |
9938af6a JH |
238 | NULL |
239 | }; | |
240 | const char **p; | |
241 | ||
3c3852e3 | 242 | if (len == 40 && !get_sha1_hex(str, sha1)) |
9938af6a JH |
243 | return 0; |
244 | ||
af13cdf2 | 245 | /* Accept only unambiguous ref paths. */ |
6677c466 | 246 | if (ambiguous_path(str, len)) |
af13cdf2 LT |
247 | return -1; |
248 | ||
9938af6a JH |
249 | for (p = prefix; *p; p++) { |
250 | char *pathname = git_path("%s/%.*s", *p, len, str); | |
011fbc7f JH |
251 | if (!read_ref(pathname, sha1)) |
252 | return 0; | |
6677c466 | 253 | } |
011fbc7f | 254 | return -1; |
9938af6a JH |
255 | } |
256 | ||
257 | static int get_sha1_1(const char *name, int len, unsigned char *sha1); | |
258 | ||
259 | static int get_parent(const char *name, int len, | |
260 | unsigned char *result, int idx) | |
261 | { | |
262 | unsigned char sha1[20]; | |
263 | int ret = get_sha1_1(name, len, sha1); | |
264 | struct commit *commit; | |
265 | struct commit_list *p; | |
266 | ||
267 | if (ret) | |
268 | return ret; | |
269 | commit = lookup_commit_reference(sha1); | |
270 | if (!commit) | |
271 | return -1; | |
272 | if (parse_commit(commit)) | |
273 | return -1; | |
274 | if (!idx) { | |
275 | memcpy(result, commit->object.sha1, 20); | |
276 | return 0; | |
277 | } | |
278 | p = commit->parents; | |
279 | while (p) { | |
280 | if (!--idx) { | |
281 | memcpy(result, p->item->object.sha1, 20); | |
282 | return 0; | |
283 | } | |
284 | p = p->next; | |
285 | } | |
286 | return -1; | |
287 | } | |
288 | ||
4f7599ac JH |
289 | static int get_nth_ancestor(const char *name, int len, |
290 | unsigned char *result, int generation) | |
291 | { | |
292 | unsigned char sha1[20]; | |
293 | int ret = get_sha1_1(name, len, sha1); | |
294 | if (ret) | |
295 | return ret; | |
296 | ||
297 | while (generation--) { | |
298 | struct commit *commit = lookup_commit_reference(sha1); | |
299 | ||
300 | if (!commit || parse_commit(commit) || !commit->parents) | |
301 | return -1; | |
302 | memcpy(sha1, commit->parents->item->object.sha1, 20); | |
303 | } | |
304 | memcpy(result, sha1, 20); | |
305 | return 0; | |
306 | } | |
307 | ||
5385f52d JH |
308 | static int peel_onion(const char *name, int len, unsigned char *sha1) |
309 | { | |
310 | unsigned char outer[20]; | |
311 | const char *sp; | |
312 | const char *type_string = NULL; | |
313 | struct object *o; | |
314 | ||
315 | /* | |
316 | * "ref^{type}" dereferences ref repeatedly until you cannot | |
317 | * dereference anymore, or you get an object of given type, | |
318 | * whichever comes first. "ref^{}" means just dereference | |
319 | * tags until you get a non-tag. "ref^0" is a shorthand for | |
320 | * "ref^{commit}". "commit^{tree}" could be used to find the | |
321 | * top-level tree of the given commit. | |
322 | */ | |
323 | if (len < 4 || name[len-1] != '}') | |
324 | return -1; | |
325 | ||
326 | for (sp = name + len - 1; name <= sp; sp--) { | |
327 | int ch = *sp; | |
328 | if (ch == '{' && name < sp && sp[-1] == '^') | |
329 | break; | |
330 | } | |
331 | if (sp <= name) | |
332 | return -1; | |
333 | ||
334 | sp++; /* beginning of type name, or closing brace for empty */ | |
335 | if (!strncmp(commit_type, sp, 6) && sp[6] == '}') | |
336 | type_string = commit_type; | |
337 | else if (!strncmp(tree_type, sp, 4) && sp[4] == '}') | |
338 | type_string = tree_type; | |
339 | else if (!strncmp(blob_type, sp, 4) && sp[4] == '}') | |
340 | type_string = blob_type; | |
341 | else if (sp[0] == '}') | |
342 | type_string = NULL; | |
343 | else | |
344 | return -1; | |
345 | ||
346 | if (get_sha1_1(name, sp - name - 2, outer)) | |
347 | return -1; | |
348 | ||
349 | o = parse_object(outer); | |
350 | if (!o) | |
351 | return -1; | |
352 | if (!type_string) { | |
9534f40b | 353 | o = deref_tag(o, name, sp - name - 2); |
6e1c6c10 JH |
354 | if (!o || (!o->parsed && !parse_object(o->sha1))) |
355 | return -1; | |
5385f52d JH |
356 | memcpy(sha1, o->sha1, 20); |
357 | } | |
358 | else { | |
359 | /* At this point, the syntax look correct, so | |
360 | * if we do not get the needed object, we should | |
361 | * barf. | |
362 | */ | |
363 | ||
364 | while (1) { | |
6e1c6c10 | 365 | if (!o || (!o->parsed && !parse_object(o->sha1))) |
5385f52d JH |
366 | return -1; |
367 | if (o->type == type_string) { | |
368 | memcpy(sha1, o->sha1, 20); | |
369 | return 0; | |
370 | } | |
371 | if (o->type == tag_type) | |
372 | o = ((struct tag*) o)->tagged; | |
373 | else if (o->type == commit_type) | |
374 | o = &(((struct commit *) o)->tree->object); | |
375 | else | |
376 | return error("%.*s: expected %s type, but the object dereferences to %s type", | |
377 | len, name, type_string, | |
378 | o->type); | |
379 | if (!o->parsed) | |
380 | parse_object(o->sha1); | |
381 | } | |
382 | } | |
383 | return 0; | |
384 | } | |
385 | ||
9938af6a JH |
386 | static int get_sha1_1(const char *name, int len, unsigned char *sha1) |
387 | { | |
388 | int parent, ret; | |
4f7599ac | 389 | const char *cp; |
9938af6a JH |
390 | |
391 | /* foo^[0-9] or foo^ (== foo^1); we do not do more than 9 parents. */ | |
392 | if (len > 2 && name[len-2] == '^' && | |
393 | name[len-1] >= '0' && name[len-1] <= '9') { | |
394 | parent = name[len-1] - '0'; | |
395 | len -= 2; | |
396 | } | |
ef0bd2e6 | 397 | else if (len > 1 && name[len-1] == '^') { |
9938af6a | 398 | parent = 1; |
ef0bd2e6 JS |
399 | len--; |
400 | } else | |
9938af6a JH |
401 | parent = -1; |
402 | ||
02a4a32c LT |
403 | if (parent >= 0) |
404 | return get_parent(name, len, sha1, parent); | |
405 | ||
4f7599ac JH |
406 | /* "name~3" is "name^^^", |
407 | * "name~12" is "name^^^^^^^^^^^^", and | |
408 | * "name~" and "name~0" are name -- not "name^0"! | |
409 | */ | |
410 | parent = 0; | |
411 | for (cp = name + len - 1; name <= cp; cp--) { | |
412 | int ch = *cp; | |
413 | if ('0' <= ch && ch <= '9') | |
414 | continue; | |
415 | if (ch != '~') | |
416 | parent = -1; | |
417 | break; | |
418 | } | |
419 | if (!parent && *cp == '~') { | |
420 | int len1 = cp - name; | |
421 | cp++; | |
422 | while (cp < name + len) | |
423 | parent = parent * 10 + *cp++ - '0'; | |
424 | return get_nth_ancestor(name, len1, sha1, parent); | |
425 | } | |
426 | ||
5385f52d JH |
427 | ret = peel_onion(name, len, sha1); |
428 | if (!ret) | |
429 | return 0; | |
430 | ||
9938af6a JH |
431 | ret = get_sha1_basic(name, len, sha1); |
432 | if (!ret) | |
433 | return 0; | |
013f276e | 434 | return get_short_sha1(name, len, sha1, 0); |
9938af6a JH |
435 | } |
436 | ||
437 | /* | |
438 | * This is like "get_sha1_basic()", except it allows "sha1 expressions", | |
439 | * notably "xyz^" for "parent of xyz" | |
440 | */ | |
441 | int get_sha1(const char *name, unsigned char *sha1) | |
442 | { | |
99a19b43 | 443 | prepare_alt_odb(); |
9938af6a JH |
444 | return get_sha1_1(name, strlen(name), sha1); |
445 | } |