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1 | #include "cache.h" | |
2 | #include "lockfile.h" | |
3 | #include "refs.h" | |
4 | #include "object.h" | |
5 | #include "tag.h" | |
6 | #include "dir.h" | |
7 | #include "string-list.h" | |
8 | ||
9 | /* | |
10 | * How to handle various characters in refnames: | |
11 | * 0: An acceptable character for refs | |
12 | * 1: End-of-component | |
13 | * 2: ., look for a preceding . to reject .. in refs | |
14 | * 3: {, look for a preceding @ to reject @{ in refs | |
15 | * 4: A bad character: ASCII control characters, "~", "^", ":" or SP | |
16 | */ | |
17 | static unsigned char refname_disposition[256] = { | |
18 | 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, | |
19 | 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, | |
20 | 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 2, 1, | |
21 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4, | |
22 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | |
23 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0, | |
24 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | |
25 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4 | |
26 | }; | |
27 | ||
28 | /* | |
29 | * Used as a flag to ref_transaction_delete when a loose ref is being | |
30 | * pruned. | |
31 | */ | |
32 | #define REF_ISPRUNING 0x0100 | |
33 | /* | |
34 | * Try to read one refname component from the front of refname. | |
35 | * Return the length of the component found, or -1 if the component is | |
36 | * not legal. It is legal if it is something reasonable to have under | |
37 | * ".git/refs/"; We do not like it if: | |
38 | * | |
39 | * - any path component of it begins with ".", or | |
40 | * - it has double dots "..", or | |
41 | * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or | |
42 | * - it ends with a "/". | |
43 | * - it ends with ".lock" | |
44 | * - it contains a "\" (backslash) | |
45 | */ | |
46 | static int check_refname_component(const char *refname, int flags) | |
47 | { | |
48 | const char *cp; | |
49 | char last = '\0'; | |
50 | ||
51 | for (cp = refname; ; cp++) { | |
52 | int ch = *cp & 255; | |
53 | unsigned char disp = refname_disposition[ch]; | |
54 | switch (disp) { | |
55 | case 1: | |
56 | goto out; | |
57 | case 2: | |
58 | if (last == '.') | |
59 | return -1; /* Refname contains "..". */ | |
60 | break; | |
61 | case 3: | |
62 | if (last == '@') | |
63 | return -1; /* Refname contains "@{". */ | |
64 | break; | |
65 | case 4: | |
66 | return -1; | |
67 | } | |
68 | last = ch; | |
69 | } | |
70 | out: | |
71 | if (cp == refname) | |
72 | return 0; /* Component has zero length. */ | |
73 | if (refname[0] == '.') | |
74 | return -1; /* Component starts with '.'. */ | |
75 | if (cp - refname >= LOCK_SUFFIX_LEN && | |
76 | !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN)) | |
77 | return -1; /* Refname ends with ".lock". */ | |
78 | return cp - refname; | |
79 | } | |
80 | ||
81 | int check_refname_format(const char *refname, int flags) | |
82 | { | |
83 | int component_len, component_count = 0; | |
84 | ||
85 | if (!strcmp(refname, "@")) | |
86 | /* Refname is a single character '@'. */ | |
87 | return -1; | |
88 | ||
89 | while (1) { | |
90 | /* We are at the start of a path component. */ | |
91 | component_len = check_refname_component(refname, flags); | |
92 | if (component_len <= 0) { | |
93 | if ((flags & REFNAME_REFSPEC_PATTERN) && | |
94 | refname[0] == '*' && | |
95 | (refname[1] == '\0' || refname[1] == '/')) { | |
96 | /* Accept one wildcard as a full refname component. */ | |
97 | flags &= ~REFNAME_REFSPEC_PATTERN; | |
98 | component_len = 1; | |
99 | } else { | |
100 | return -1; | |
101 | } | |
102 | } | |
103 | component_count++; | |
104 | if (refname[component_len] == '\0') | |
105 | break; | |
106 | /* Skip to next component. */ | |
107 | refname += component_len + 1; | |
108 | } | |
109 | ||
110 | if (refname[component_len - 1] == '.') | |
111 | return -1; /* Refname ends with '.'. */ | |
112 | if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2) | |
113 | return -1; /* Refname has only one component. */ | |
114 | return 0; | |
115 | } | |
116 | ||
117 | struct ref_entry; | |
118 | ||
119 | /* | |
120 | * Information used (along with the information in ref_entry) to | |
121 | * describe a single cached reference. This data structure only | |
122 | * occurs embedded in a union in struct ref_entry, and only when | |
123 | * (ref_entry->flag & REF_DIR) is zero. | |
124 | */ | |
125 | struct ref_value { | |
126 | /* | |
127 | * The name of the object to which this reference resolves | |
128 | * (which may be a tag object). If REF_ISBROKEN, this is | |
129 | * null. If REF_ISSYMREF, then this is the name of the object | |
130 | * referred to by the last reference in the symlink chain. | |
131 | */ | |
132 | unsigned char sha1[20]; | |
133 | ||
134 | /* | |
135 | * If REF_KNOWS_PEELED, then this field holds the peeled value | |
136 | * of this reference, or null if the reference is known not to | |
137 | * be peelable. See the documentation for peel_ref() for an | |
138 | * exact definition of "peelable". | |
139 | */ | |
140 | unsigned char peeled[20]; | |
141 | }; | |
142 | ||
143 | struct ref_cache; | |
144 | ||
145 | /* | |
146 | * Information used (along with the information in ref_entry) to | |
147 | * describe a level in the hierarchy of references. This data | |
148 | * structure only occurs embedded in a union in struct ref_entry, and | |
149 | * only when (ref_entry.flag & REF_DIR) is set. In that case, | |
150 | * (ref_entry.flag & REF_INCOMPLETE) determines whether the references | |
151 | * in the directory have already been read: | |
152 | * | |
153 | * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose | |
154 | * or packed references, already read. | |
155 | * | |
156 | * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose | |
157 | * references that hasn't been read yet (nor has any of its | |
158 | * subdirectories). | |
159 | * | |
160 | * Entries within a directory are stored within a growable array of | |
161 | * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < | |
162 | * sorted are sorted by their component name in strcmp() order and the | |
163 | * remaining entries are unsorted. | |
164 | * | |
165 | * Loose references are read lazily, one directory at a time. When a | |
166 | * directory of loose references is read, then all of the references | |
167 | * in that directory are stored, and REF_INCOMPLETE stubs are created | |
168 | * for any subdirectories, but the subdirectories themselves are not | |
169 | * read. The reading is triggered by get_ref_dir(). | |
170 | */ | |
171 | struct ref_dir { | |
172 | int nr, alloc; | |
173 | ||
174 | /* | |
175 | * Entries with index 0 <= i < sorted are sorted by name. New | |
176 | * entries are appended to the list unsorted, and are sorted | |
177 | * only when required; thus we avoid the need to sort the list | |
178 | * after the addition of every reference. | |
179 | */ | |
180 | int sorted; | |
181 | ||
182 | /* A pointer to the ref_cache that contains this ref_dir. */ | |
183 | struct ref_cache *ref_cache; | |
184 | ||
185 | struct ref_entry **entries; | |
186 | }; | |
187 | ||
188 | /* | |
189 | * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, | |
190 | * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see | |
191 | * refs.h. | |
192 | */ | |
193 | ||
194 | /* | |
195 | * The field ref_entry->u.value.peeled of this value entry contains | |
196 | * the correct peeled value for the reference, which might be | |
197 | * null_sha1 if the reference is not a tag or if it is broken. | |
198 | */ | |
199 | #define REF_KNOWS_PEELED 0x08 | |
200 | ||
201 | /* ref_entry represents a directory of references */ | |
202 | #define REF_DIR 0x10 | |
203 | ||
204 | /* | |
205 | * Entry has not yet been read from disk (used only for REF_DIR | |
206 | * entries representing loose references) | |
207 | */ | |
208 | #define REF_INCOMPLETE 0x20 | |
209 | ||
210 | /* | |
211 | * A ref_entry represents either a reference or a "subdirectory" of | |
212 | * references. | |
213 | * | |
214 | * Each directory in the reference namespace is represented by a | |
215 | * ref_entry with (flags & REF_DIR) set and containing a subdir member | |
216 | * that holds the entries in that directory that have been read so | |
217 | * far. If (flags & REF_INCOMPLETE) is set, then the directory and | |
218 | * its subdirectories haven't been read yet. REF_INCOMPLETE is only | |
219 | * used for loose reference directories. | |
220 | * | |
221 | * References are represented by a ref_entry with (flags & REF_DIR) | |
222 | * unset and a value member that describes the reference's value. The | |
223 | * flag member is at the ref_entry level, but it is also needed to | |
224 | * interpret the contents of the value field (in other words, a | |
225 | * ref_value object is not very much use without the enclosing | |
226 | * ref_entry). | |
227 | * | |
228 | * Reference names cannot end with slash and directories' names are | |
229 | * always stored with a trailing slash (except for the top-level | |
230 | * directory, which is always denoted by ""). This has two nice | |
231 | * consequences: (1) when the entries in each subdir are sorted | |
232 | * lexicographically by name (as they usually are), the references in | |
233 | * a whole tree can be generated in lexicographic order by traversing | |
234 | * the tree in left-to-right, depth-first order; (2) the names of | |
235 | * references and subdirectories cannot conflict, and therefore the | |
236 | * presence of an empty subdirectory does not block the creation of a | |
237 | * similarly-named reference. (The fact that reference names with the | |
238 | * same leading components can conflict *with each other* is a | |
239 | * separate issue that is regulated by is_refname_available().) | |
240 | * | |
241 | * Please note that the name field contains the fully-qualified | |
242 | * reference (or subdirectory) name. Space could be saved by only | |
243 | * storing the relative names. But that would require the full names | |
244 | * to be generated on the fly when iterating in do_for_each_ref(), and | |
245 | * would break callback functions, who have always been able to assume | |
246 | * that the name strings that they are passed will not be freed during | |
247 | * the iteration. | |
248 | */ | |
249 | struct ref_entry { | |
250 | unsigned char flag; /* ISSYMREF? ISPACKED? */ | |
251 | union { | |
252 | struct ref_value value; /* if not (flags&REF_DIR) */ | |
253 | struct ref_dir subdir; /* if (flags&REF_DIR) */ | |
254 | } u; | |
255 | /* | |
256 | * The full name of the reference (e.g., "refs/heads/master") | |
257 | * or the full name of the directory with a trailing slash | |
258 | * (e.g., "refs/heads/"): | |
259 | */ | |
260 | char name[FLEX_ARRAY]; | |
261 | }; | |
262 | ||
263 | static void read_loose_refs(const char *dirname, struct ref_dir *dir); | |
264 | ||
265 | static struct ref_dir *get_ref_dir(struct ref_entry *entry) | |
266 | { | |
267 | struct ref_dir *dir; | |
268 | assert(entry->flag & REF_DIR); | |
269 | dir = &entry->u.subdir; | |
270 | if (entry->flag & REF_INCOMPLETE) { | |
271 | read_loose_refs(entry->name, dir); | |
272 | entry->flag &= ~REF_INCOMPLETE; | |
273 | } | |
274 | return dir; | |
275 | } | |
276 | ||
277 | static struct ref_entry *create_ref_entry(const char *refname, | |
278 | const unsigned char *sha1, int flag, | |
279 | int check_name) | |
280 | { | |
281 | int len; | |
282 | struct ref_entry *ref; | |
283 | ||
284 | if (check_name && | |
285 | check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) | |
286 | die("Reference has invalid format: '%s'", refname); | |
287 | len = strlen(refname) + 1; | |
288 | ref = xmalloc(sizeof(struct ref_entry) + len); | |
289 | hashcpy(ref->u.value.sha1, sha1); | |
290 | hashclr(ref->u.value.peeled); | |
291 | memcpy(ref->name, refname, len); | |
292 | ref->flag = flag; | |
293 | return ref; | |
294 | } | |
295 | ||
296 | static void clear_ref_dir(struct ref_dir *dir); | |
297 | ||
298 | static void free_ref_entry(struct ref_entry *entry) | |
299 | { | |
300 | if (entry->flag & REF_DIR) { | |
301 | /* | |
302 | * Do not use get_ref_dir() here, as that might | |
303 | * trigger the reading of loose refs. | |
304 | */ | |
305 | clear_ref_dir(&entry->u.subdir); | |
306 | } | |
307 | free(entry); | |
308 | } | |
309 | ||
310 | /* | |
311 | * Add a ref_entry to the end of dir (unsorted). Entry is always | |
312 | * stored directly in dir; no recursion into subdirectories is | |
313 | * done. | |
314 | */ | |
315 | static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry) | |
316 | { | |
317 | ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc); | |
318 | dir->entries[dir->nr++] = entry; | |
319 | /* optimize for the case that entries are added in order */ | |
320 | if (dir->nr == 1 || | |
321 | (dir->nr == dir->sorted + 1 && | |
322 | strcmp(dir->entries[dir->nr - 2]->name, | |
323 | dir->entries[dir->nr - 1]->name) < 0)) | |
324 | dir->sorted = dir->nr; | |
325 | } | |
326 | ||
327 | /* | |
328 | * Clear and free all entries in dir, recursively. | |
329 | */ | |
330 | static void clear_ref_dir(struct ref_dir *dir) | |
331 | { | |
332 | int i; | |
333 | for (i = 0; i < dir->nr; i++) | |
334 | free_ref_entry(dir->entries[i]); | |
335 | free(dir->entries); | |
336 | dir->sorted = dir->nr = dir->alloc = 0; | |
337 | dir->entries = NULL; | |
338 | } | |
339 | ||
340 | /* | |
341 | * Create a struct ref_entry object for the specified dirname. | |
342 | * dirname is the name of the directory with a trailing slash (e.g., | |
343 | * "refs/heads/") or "" for the top-level directory. | |
344 | */ | |
345 | static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache, | |
346 | const char *dirname, size_t len, | |
347 | int incomplete) | |
348 | { | |
349 | struct ref_entry *direntry; | |
350 | direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1); | |
351 | memcpy(direntry->name, dirname, len); | |
352 | direntry->name[len] = '\0'; | |
353 | direntry->u.subdir.ref_cache = ref_cache; | |
354 | direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0); | |
355 | return direntry; | |
356 | } | |
357 | ||
358 | static int ref_entry_cmp(const void *a, const void *b) | |
359 | { | |
360 | struct ref_entry *one = *(struct ref_entry **)a; | |
361 | struct ref_entry *two = *(struct ref_entry **)b; | |
362 | return strcmp(one->name, two->name); | |
363 | } | |
364 | ||
365 | static void sort_ref_dir(struct ref_dir *dir); | |
366 | ||
367 | struct string_slice { | |
368 | size_t len; | |
369 | const char *str; | |
370 | }; | |
371 | ||
372 | static int ref_entry_cmp_sslice(const void *key_, const void *ent_) | |
373 | { | |
374 | const struct string_slice *key = key_; | |
375 | const struct ref_entry *ent = *(const struct ref_entry * const *)ent_; | |
376 | int cmp = strncmp(key->str, ent->name, key->len); | |
377 | if (cmp) | |
378 | return cmp; | |
379 | return '\0' - (unsigned char)ent->name[key->len]; | |
380 | } | |
381 | ||
382 | /* | |
383 | * Return the index of the entry with the given refname from the | |
384 | * ref_dir (non-recursively), sorting dir if necessary. Return -1 if | |
385 | * no such entry is found. dir must already be complete. | |
386 | */ | |
387 | static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len) | |
388 | { | |
389 | struct ref_entry **r; | |
390 | struct string_slice key; | |
391 | ||
392 | if (refname == NULL || !dir->nr) | |
393 | return -1; | |
394 | ||
395 | sort_ref_dir(dir); | |
396 | key.len = len; | |
397 | key.str = refname; | |
398 | r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries), | |
399 | ref_entry_cmp_sslice); | |
400 | ||
401 | if (r == NULL) | |
402 | return -1; | |
403 | ||
404 | return r - dir->entries; | |
405 | } | |
406 | ||
407 | /* | |
408 | * Search for a directory entry directly within dir (without | |
409 | * recursing). Sort dir if necessary. subdirname must be a directory | |
410 | * name (i.e., end in '/'). If mkdir is set, then create the | |
411 | * directory if it is missing; otherwise, return NULL if the desired | |
412 | * directory cannot be found. dir must already be complete. | |
413 | */ | |
414 | static struct ref_dir *search_for_subdir(struct ref_dir *dir, | |
415 | const char *subdirname, size_t len, | |
416 | int mkdir) | |
417 | { | |
418 | int entry_index = search_ref_dir(dir, subdirname, len); | |
419 | struct ref_entry *entry; | |
420 | if (entry_index == -1) { | |
421 | if (!mkdir) | |
422 | return NULL; | |
423 | /* | |
424 | * Since dir is complete, the absence of a subdir | |
425 | * means that the subdir really doesn't exist; | |
426 | * therefore, create an empty record for it but mark | |
427 | * the record complete. | |
428 | */ | |
429 | entry = create_dir_entry(dir->ref_cache, subdirname, len, 0); | |
430 | add_entry_to_dir(dir, entry); | |
431 | } else { | |
432 | entry = dir->entries[entry_index]; | |
433 | } | |
434 | return get_ref_dir(entry); | |
435 | } | |
436 | ||
437 | /* | |
438 | * If refname is a reference name, find the ref_dir within the dir | |
439 | * tree that should hold refname. If refname is a directory name | |
440 | * (i.e., ends in '/'), then return that ref_dir itself. dir must | |
441 | * represent the top-level directory and must already be complete. | |
442 | * Sort ref_dirs and recurse into subdirectories as necessary. If | |
443 | * mkdir is set, then create any missing directories; otherwise, | |
444 | * return NULL if the desired directory cannot be found. | |
445 | */ | |
446 | static struct ref_dir *find_containing_dir(struct ref_dir *dir, | |
447 | const char *refname, int mkdir) | |
448 | { | |
449 | const char *slash; | |
450 | for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { | |
451 | size_t dirnamelen = slash - refname + 1; | |
452 | struct ref_dir *subdir; | |
453 | subdir = search_for_subdir(dir, refname, dirnamelen, mkdir); | |
454 | if (!subdir) { | |
455 | dir = NULL; | |
456 | break; | |
457 | } | |
458 | dir = subdir; | |
459 | } | |
460 | ||
461 | return dir; | |
462 | } | |
463 | ||
464 | /* | |
465 | * Find the value entry with the given name in dir, sorting ref_dirs | |
466 | * and recursing into subdirectories as necessary. If the name is not | |
467 | * found or it corresponds to a directory entry, return NULL. | |
468 | */ | |
469 | static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname) | |
470 | { | |
471 | int entry_index; | |
472 | struct ref_entry *entry; | |
473 | dir = find_containing_dir(dir, refname, 0); | |
474 | if (!dir) | |
475 | return NULL; | |
476 | entry_index = search_ref_dir(dir, refname, strlen(refname)); | |
477 | if (entry_index == -1) | |
478 | return NULL; | |
479 | entry = dir->entries[entry_index]; | |
480 | return (entry->flag & REF_DIR) ? NULL : entry; | |
481 | } | |
482 | ||
483 | /* | |
484 | * Remove the entry with the given name from dir, recursing into | |
485 | * subdirectories as necessary. If refname is the name of a directory | |
486 | * (i.e., ends with '/'), then remove the directory and its contents. | |
487 | * If the removal was successful, return the number of entries | |
488 | * remaining in the directory entry that contained the deleted entry. | |
489 | * If the name was not found, return -1. Please note that this | |
490 | * function only deletes the entry from the cache; it does not delete | |
491 | * it from the filesystem or ensure that other cache entries (which | |
492 | * might be symbolic references to the removed entry) are updated. | |
493 | * Nor does it remove any containing dir entries that might be made | |
494 | * empty by the removal. dir must represent the top-level directory | |
495 | * and must already be complete. | |
496 | */ | |
497 | static int remove_entry(struct ref_dir *dir, const char *refname) | |
498 | { | |
499 | int refname_len = strlen(refname); | |
500 | int entry_index; | |
501 | struct ref_entry *entry; | |
502 | int is_dir = refname[refname_len - 1] == '/'; | |
503 | if (is_dir) { | |
504 | /* | |
505 | * refname represents a reference directory. Remove | |
506 | * the trailing slash; otherwise we will get the | |
507 | * directory *representing* refname rather than the | |
508 | * one *containing* it. | |
509 | */ | |
510 | char *dirname = xmemdupz(refname, refname_len - 1); | |
511 | dir = find_containing_dir(dir, dirname, 0); | |
512 | free(dirname); | |
513 | } else { | |
514 | dir = find_containing_dir(dir, refname, 0); | |
515 | } | |
516 | if (!dir) | |
517 | return -1; | |
518 | entry_index = search_ref_dir(dir, refname, refname_len); | |
519 | if (entry_index == -1) | |
520 | return -1; | |
521 | entry = dir->entries[entry_index]; | |
522 | ||
523 | memmove(&dir->entries[entry_index], | |
524 | &dir->entries[entry_index + 1], | |
525 | (dir->nr - entry_index - 1) * sizeof(*dir->entries) | |
526 | ); | |
527 | dir->nr--; | |
528 | if (dir->sorted > entry_index) | |
529 | dir->sorted--; | |
530 | free_ref_entry(entry); | |
531 | return dir->nr; | |
532 | } | |
533 | ||
534 | /* | |
535 | * Add a ref_entry to the ref_dir (unsorted), recursing into | |
536 | * subdirectories as necessary. dir must represent the top-level | |
537 | * directory. Return 0 on success. | |
538 | */ | |
539 | static int add_ref(struct ref_dir *dir, struct ref_entry *ref) | |
540 | { | |
541 | dir = find_containing_dir(dir, ref->name, 1); | |
542 | if (!dir) | |
543 | return -1; | |
544 | add_entry_to_dir(dir, ref); | |
545 | return 0; | |
546 | } | |
547 | ||
548 | /* | |
549 | * Emit a warning and return true iff ref1 and ref2 have the same name | |
550 | * and the same sha1. Die if they have the same name but different | |
551 | * sha1s. | |
552 | */ | |
553 | static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2) | |
554 | { | |
555 | if (strcmp(ref1->name, ref2->name)) | |
556 | return 0; | |
557 | ||
558 | /* Duplicate name; make sure that they don't conflict: */ | |
559 | ||
560 | if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) | |
561 | /* This is impossible by construction */ | |
562 | die("Reference directory conflict: %s", ref1->name); | |
563 | ||
564 | if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1)) | |
565 | die("Duplicated ref, and SHA1s don't match: %s", ref1->name); | |
566 | ||
567 | warning("Duplicated ref: %s", ref1->name); | |
568 | return 1; | |
569 | } | |
570 | ||
571 | /* | |
572 | * Sort the entries in dir non-recursively (if they are not already | |
573 | * sorted) and remove any duplicate entries. | |
574 | */ | |
575 | static void sort_ref_dir(struct ref_dir *dir) | |
576 | { | |
577 | int i, j; | |
578 | struct ref_entry *last = NULL; | |
579 | ||
580 | /* | |
581 | * This check also prevents passing a zero-length array to qsort(), | |
582 | * which is a problem on some platforms. | |
583 | */ | |
584 | if (dir->sorted == dir->nr) | |
585 | return; | |
586 | ||
587 | qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp); | |
588 | ||
589 | /* Remove any duplicates: */ | |
590 | for (i = 0, j = 0; j < dir->nr; j++) { | |
591 | struct ref_entry *entry = dir->entries[j]; | |
592 | if (last && is_dup_ref(last, entry)) | |
593 | free_ref_entry(entry); | |
594 | else | |
595 | last = dir->entries[i++] = entry; | |
596 | } | |
597 | dir->sorted = dir->nr = i; | |
598 | } | |
599 | ||
600 | /* Include broken references in a do_for_each_ref*() iteration: */ | |
601 | #define DO_FOR_EACH_INCLUDE_BROKEN 0x01 | |
602 | ||
603 | /* | |
604 | * Return true iff the reference described by entry can be resolved to | |
605 | * an object in the database. Emit a warning if the referred-to | |
606 | * object does not exist. | |
607 | */ | |
608 | static int ref_resolves_to_object(struct ref_entry *entry) | |
609 | { | |
610 | if (entry->flag & REF_ISBROKEN) | |
611 | return 0; | |
612 | if (!has_sha1_file(entry->u.value.sha1)) { | |
613 | error("%s does not point to a valid object!", entry->name); | |
614 | return 0; | |
615 | } | |
616 | return 1; | |
617 | } | |
618 | ||
619 | /* | |
620 | * current_ref is a performance hack: when iterating over references | |
621 | * using the for_each_ref*() functions, current_ref is set to the | |
622 | * current reference's entry before calling the callback function. If | |
623 | * the callback function calls peel_ref(), then peel_ref() first | |
624 | * checks whether the reference to be peeled is the current reference | |
625 | * (it usually is) and if so, returns that reference's peeled version | |
626 | * if it is available. This avoids a refname lookup in a common case. | |
627 | */ | |
628 | static struct ref_entry *current_ref; | |
629 | ||
630 | typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data); | |
631 | ||
632 | struct ref_entry_cb { | |
633 | const char *base; | |
634 | int trim; | |
635 | int flags; | |
636 | each_ref_fn *fn; | |
637 | void *cb_data; | |
638 | }; | |
639 | ||
640 | /* | |
641 | * Handle one reference in a do_for_each_ref*()-style iteration, | |
642 | * calling an each_ref_fn for each entry. | |
643 | */ | |
644 | static int do_one_ref(struct ref_entry *entry, void *cb_data) | |
645 | { | |
646 | struct ref_entry_cb *data = cb_data; | |
647 | struct ref_entry *old_current_ref; | |
648 | int retval; | |
649 | ||
650 | if (!starts_with(entry->name, data->base)) | |
651 | return 0; | |
652 | ||
653 | if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) && | |
654 | !ref_resolves_to_object(entry)) | |
655 | return 0; | |
656 | ||
657 | /* Store the old value, in case this is a recursive call: */ | |
658 | old_current_ref = current_ref; | |
659 | current_ref = entry; | |
660 | retval = data->fn(entry->name + data->trim, entry->u.value.sha1, | |
661 | entry->flag, data->cb_data); | |
662 | current_ref = old_current_ref; | |
663 | return retval; | |
664 | } | |
665 | ||
666 | /* | |
667 | * Call fn for each reference in dir that has index in the range | |
668 | * offset <= index < dir->nr. Recurse into subdirectories that are in | |
669 | * that index range, sorting them before iterating. This function | |
670 | * does not sort dir itself; it should be sorted beforehand. fn is | |
671 | * called for all references, including broken ones. | |
672 | */ | |
673 | static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset, | |
674 | each_ref_entry_fn fn, void *cb_data) | |
675 | { | |
676 | int i; | |
677 | assert(dir->sorted == dir->nr); | |
678 | for (i = offset; i < dir->nr; i++) { | |
679 | struct ref_entry *entry = dir->entries[i]; | |
680 | int retval; | |
681 | if (entry->flag & REF_DIR) { | |
682 | struct ref_dir *subdir = get_ref_dir(entry); | |
683 | sort_ref_dir(subdir); | |
684 | retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data); | |
685 | } else { | |
686 | retval = fn(entry, cb_data); | |
687 | } | |
688 | if (retval) | |
689 | return retval; | |
690 | } | |
691 | return 0; | |
692 | } | |
693 | ||
694 | /* | |
695 | * Call fn for each reference in the union of dir1 and dir2, in order | |
696 | * by refname. Recurse into subdirectories. If a value entry appears | |
697 | * in both dir1 and dir2, then only process the version that is in | |
698 | * dir2. The input dirs must already be sorted, but subdirs will be | |
699 | * sorted as needed. fn is called for all references, including | |
700 | * broken ones. | |
701 | */ | |
702 | static int do_for_each_entry_in_dirs(struct ref_dir *dir1, | |
703 | struct ref_dir *dir2, | |
704 | each_ref_entry_fn fn, void *cb_data) | |
705 | { | |
706 | int retval; | |
707 | int i1 = 0, i2 = 0; | |
708 | ||
709 | assert(dir1->sorted == dir1->nr); | |
710 | assert(dir2->sorted == dir2->nr); | |
711 | while (1) { | |
712 | struct ref_entry *e1, *e2; | |
713 | int cmp; | |
714 | if (i1 == dir1->nr) { | |
715 | return do_for_each_entry_in_dir(dir2, i2, fn, cb_data); | |
716 | } | |
717 | if (i2 == dir2->nr) { | |
718 | return do_for_each_entry_in_dir(dir1, i1, fn, cb_data); | |
719 | } | |
720 | e1 = dir1->entries[i1]; | |
721 | e2 = dir2->entries[i2]; | |
722 | cmp = strcmp(e1->name, e2->name); | |
723 | if (cmp == 0) { | |
724 | if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) { | |
725 | /* Both are directories; descend them in parallel. */ | |
726 | struct ref_dir *subdir1 = get_ref_dir(e1); | |
727 | struct ref_dir *subdir2 = get_ref_dir(e2); | |
728 | sort_ref_dir(subdir1); | |
729 | sort_ref_dir(subdir2); | |
730 | retval = do_for_each_entry_in_dirs( | |
731 | subdir1, subdir2, fn, cb_data); | |
732 | i1++; | |
733 | i2++; | |
734 | } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) { | |
735 | /* Both are references; ignore the one from dir1. */ | |
736 | retval = fn(e2, cb_data); | |
737 | i1++; | |
738 | i2++; | |
739 | } else { | |
740 | die("conflict between reference and directory: %s", | |
741 | e1->name); | |
742 | } | |
743 | } else { | |
744 | struct ref_entry *e; | |
745 | if (cmp < 0) { | |
746 | e = e1; | |
747 | i1++; | |
748 | } else { | |
749 | e = e2; | |
750 | i2++; | |
751 | } | |
752 | if (e->flag & REF_DIR) { | |
753 | struct ref_dir *subdir = get_ref_dir(e); | |
754 | sort_ref_dir(subdir); | |
755 | retval = do_for_each_entry_in_dir( | |
756 | subdir, 0, fn, cb_data); | |
757 | } else { | |
758 | retval = fn(e, cb_data); | |
759 | } | |
760 | } | |
761 | if (retval) | |
762 | return retval; | |
763 | } | |
764 | } | |
765 | ||
766 | /* | |
767 | * Load all of the refs from the dir into our in-memory cache. The hard work | |
768 | * of loading loose refs is done by get_ref_dir(), so we just need to recurse | |
769 | * through all of the sub-directories. We do not even need to care about | |
770 | * sorting, as traversal order does not matter to us. | |
771 | */ | |
772 | static void prime_ref_dir(struct ref_dir *dir) | |
773 | { | |
774 | int i; | |
775 | for (i = 0; i < dir->nr; i++) { | |
776 | struct ref_entry *entry = dir->entries[i]; | |
777 | if (entry->flag & REF_DIR) | |
778 | prime_ref_dir(get_ref_dir(entry)); | |
779 | } | |
780 | } | |
781 | ||
782 | static int entry_matches(struct ref_entry *entry, const struct string_list *list) | |
783 | { | |
784 | return list && string_list_has_string(list, entry->name); | |
785 | } | |
786 | ||
787 | struct nonmatching_ref_data { | |
788 | const struct string_list *skip; | |
789 | struct ref_entry *found; | |
790 | }; | |
791 | ||
792 | static int nonmatching_ref_fn(struct ref_entry *entry, void *vdata) | |
793 | { | |
794 | struct nonmatching_ref_data *data = vdata; | |
795 | ||
796 | if (entry_matches(entry, data->skip)) | |
797 | return 0; | |
798 | ||
799 | data->found = entry; | |
800 | return 1; | |
801 | } | |
802 | ||
803 | static void report_refname_conflict(struct ref_entry *entry, | |
804 | const char *refname) | |
805 | { | |
806 | error("'%s' exists; cannot create '%s'", entry->name, refname); | |
807 | } | |
808 | ||
809 | /* | |
810 | * Return true iff a reference named refname could be created without | |
811 | * conflicting with the name of an existing reference in dir. If | |
812 | * skip is non-NULL, ignore potential conflicts with refs in skip | |
813 | * (e.g., because they are scheduled for deletion in the same | |
814 | * operation). | |
815 | * | |
816 | * Two reference names conflict if one of them exactly matches the | |
817 | * leading components of the other; e.g., "foo/bar" conflicts with | |
818 | * both "foo" and with "foo/bar/baz" but not with "foo/bar" or | |
819 | * "foo/barbados". | |
820 | * | |
821 | * skip must be sorted. | |
822 | */ | |
823 | static int is_refname_available(const char *refname, | |
824 | const struct string_list *skip, | |
825 | struct ref_dir *dir) | |
826 | { | |
827 | const char *slash; | |
828 | size_t len; | |
829 | int pos; | |
830 | char *dirname; | |
831 | ||
832 | for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { | |
833 | /* | |
834 | * We are still at a leading dir of the refname; we are | |
835 | * looking for a conflict with a leaf entry. | |
836 | * | |
837 | * If we find one, we still must make sure it is | |
838 | * not in "skip". | |
839 | */ | |
840 | pos = search_ref_dir(dir, refname, slash - refname); | |
841 | if (pos >= 0) { | |
842 | struct ref_entry *entry = dir->entries[pos]; | |
843 | if (entry_matches(entry, skip)) | |
844 | return 1; | |
845 | report_refname_conflict(entry, refname); | |
846 | return 0; | |
847 | } | |
848 | ||
849 | ||
850 | /* | |
851 | * Otherwise, we can try to continue our search with | |
852 | * the next component; if we come up empty, we know | |
853 | * there is nothing under this whole prefix. | |
854 | */ | |
855 | pos = search_ref_dir(dir, refname, slash + 1 - refname); | |
856 | if (pos < 0) | |
857 | return 1; | |
858 | ||
859 | dir = get_ref_dir(dir->entries[pos]); | |
860 | } | |
861 | ||
862 | /* | |
863 | * We are at the leaf of our refname; we want to | |
864 | * make sure there are no directories which match it. | |
865 | */ | |
866 | len = strlen(refname); | |
867 | dirname = xmallocz(len + 1); | |
868 | sprintf(dirname, "%s/", refname); | |
869 | pos = search_ref_dir(dir, dirname, len + 1); | |
870 | free(dirname); | |
871 | ||
872 | if (pos >= 0) { | |
873 | /* | |
874 | * We found a directory named "refname". It is a | |
875 | * problem iff it contains any ref that is not | |
876 | * in "skip". | |
877 | */ | |
878 | struct ref_entry *entry = dir->entries[pos]; | |
879 | struct ref_dir *dir = get_ref_dir(entry); | |
880 | struct nonmatching_ref_data data; | |
881 | ||
882 | data.skip = skip; | |
883 | sort_ref_dir(dir); | |
884 | if (!do_for_each_entry_in_dir(dir, 0, nonmatching_ref_fn, &data)) | |
885 | return 1; | |
886 | ||
887 | report_refname_conflict(data.found, refname); | |
888 | return 0; | |
889 | } | |
890 | ||
891 | /* | |
892 | * There is no point in searching for another leaf | |
893 | * node which matches it; such an entry would be the | |
894 | * ref we are looking for, not a conflict. | |
895 | */ | |
896 | return 1; | |
897 | } | |
898 | ||
899 | struct packed_ref_cache { | |
900 | struct ref_entry *root; | |
901 | ||
902 | /* | |
903 | * Count of references to the data structure in this instance, | |
904 | * including the pointer from ref_cache::packed if any. The | |
905 | * data will not be freed as long as the reference count is | |
906 | * nonzero. | |
907 | */ | |
908 | unsigned int referrers; | |
909 | ||
910 | /* | |
911 | * Iff the packed-refs file associated with this instance is | |
912 | * currently locked for writing, this points at the associated | |
913 | * lock (which is owned by somebody else). The referrer count | |
914 | * is also incremented when the file is locked and decremented | |
915 | * when it is unlocked. | |
916 | */ | |
917 | struct lock_file *lock; | |
918 | ||
919 | /* The metadata from when this packed-refs cache was read */ | |
920 | struct stat_validity validity; | |
921 | }; | |
922 | ||
923 | /* | |
924 | * Future: need to be in "struct repository" | |
925 | * when doing a full libification. | |
926 | */ | |
927 | static struct ref_cache { | |
928 | struct ref_cache *next; | |
929 | struct ref_entry *loose; | |
930 | struct packed_ref_cache *packed; | |
931 | /* | |
932 | * The submodule name, or "" for the main repo. We allocate | |
933 | * length 1 rather than FLEX_ARRAY so that the main ref_cache | |
934 | * is initialized correctly. | |
935 | */ | |
936 | char name[1]; | |
937 | } ref_cache, *submodule_ref_caches; | |
938 | ||
939 | /* Lock used for the main packed-refs file: */ | |
940 | static struct lock_file packlock; | |
941 | ||
942 | /* | |
943 | * Increment the reference count of *packed_refs. | |
944 | */ | |
945 | static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs) | |
946 | { | |
947 | packed_refs->referrers++; | |
948 | } | |
949 | ||
950 | /* | |
951 | * Decrease the reference count of *packed_refs. If it goes to zero, | |
952 | * free *packed_refs and return true; otherwise return false. | |
953 | */ | |
954 | static int release_packed_ref_cache(struct packed_ref_cache *packed_refs) | |
955 | { | |
956 | if (!--packed_refs->referrers) { | |
957 | free_ref_entry(packed_refs->root); | |
958 | stat_validity_clear(&packed_refs->validity); | |
959 | free(packed_refs); | |
960 | return 1; | |
961 | } else { | |
962 | return 0; | |
963 | } | |
964 | } | |
965 | ||
966 | static void clear_packed_ref_cache(struct ref_cache *refs) | |
967 | { | |
968 | if (refs->packed) { | |
969 | struct packed_ref_cache *packed_refs = refs->packed; | |
970 | ||
971 | if (packed_refs->lock) | |
972 | die("internal error: packed-ref cache cleared while locked"); | |
973 | refs->packed = NULL; | |
974 | release_packed_ref_cache(packed_refs); | |
975 | } | |
976 | } | |
977 | ||
978 | static void clear_loose_ref_cache(struct ref_cache *refs) | |
979 | { | |
980 | if (refs->loose) { | |
981 | free_ref_entry(refs->loose); | |
982 | refs->loose = NULL; | |
983 | } | |
984 | } | |
985 | ||
986 | static struct ref_cache *create_ref_cache(const char *submodule) | |
987 | { | |
988 | int len; | |
989 | struct ref_cache *refs; | |
990 | if (!submodule) | |
991 | submodule = ""; | |
992 | len = strlen(submodule) + 1; | |
993 | refs = xcalloc(1, sizeof(struct ref_cache) + len); | |
994 | memcpy(refs->name, submodule, len); | |
995 | return refs; | |
996 | } | |
997 | ||
998 | /* | |
999 | * Return a pointer to a ref_cache for the specified submodule. For | |
1000 | * the main repository, use submodule==NULL. The returned structure | |
1001 | * will be allocated and initialized but not necessarily populated; it | |
1002 | * should not be freed. | |
1003 | */ | |
1004 | static struct ref_cache *get_ref_cache(const char *submodule) | |
1005 | { | |
1006 | struct ref_cache *refs; | |
1007 | ||
1008 | if (!submodule || !*submodule) | |
1009 | return &ref_cache; | |
1010 | ||
1011 | for (refs = submodule_ref_caches; refs; refs = refs->next) | |
1012 | if (!strcmp(submodule, refs->name)) | |
1013 | return refs; | |
1014 | ||
1015 | refs = create_ref_cache(submodule); | |
1016 | refs->next = submodule_ref_caches; | |
1017 | submodule_ref_caches = refs; | |
1018 | return refs; | |
1019 | } | |
1020 | ||
1021 | /* The length of a peeled reference line in packed-refs, including EOL: */ | |
1022 | #define PEELED_LINE_LENGTH 42 | |
1023 | ||
1024 | /* | |
1025 | * The packed-refs header line that we write out. Perhaps other | |
1026 | * traits will be added later. The trailing space is required. | |
1027 | */ | |
1028 | static const char PACKED_REFS_HEADER[] = | |
1029 | "# pack-refs with: peeled fully-peeled \n"; | |
1030 | ||
1031 | /* | |
1032 | * Parse one line from a packed-refs file. Write the SHA1 to sha1. | |
1033 | * Return a pointer to the refname within the line (null-terminated), | |
1034 | * or NULL if there was a problem. | |
1035 | */ | |
1036 | static const char *parse_ref_line(char *line, unsigned char *sha1) | |
1037 | { | |
1038 | /* | |
1039 | * 42: the answer to everything. | |
1040 | * | |
1041 | * In this case, it happens to be the answer to | |
1042 | * 40 (length of sha1 hex representation) | |
1043 | * +1 (space in between hex and name) | |
1044 | * +1 (newline at the end of the line) | |
1045 | */ | |
1046 | int len = strlen(line) - 42; | |
1047 | ||
1048 | if (len <= 0) | |
1049 | return NULL; | |
1050 | if (get_sha1_hex(line, sha1) < 0) | |
1051 | return NULL; | |
1052 | if (!isspace(line[40])) | |
1053 | return NULL; | |
1054 | line += 41; | |
1055 | if (isspace(*line)) | |
1056 | return NULL; | |
1057 | if (line[len] != '\n') | |
1058 | return NULL; | |
1059 | line[len] = 0; | |
1060 | ||
1061 | return line; | |
1062 | } | |
1063 | ||
1064 | /* | |
1065 | * Read f, which is a packed-refs file, into dir. | |
1066 | * | |
1067 | * A comment line of the form "# pack-refs with: " may contain zero or | |
1068 | * more traits. We interpret the traits as follows: | |
1069 | * | |
1070 | * No traits: | |
1071 | * | |
1072 | * Probably no references are peeled. But if the file contains a | |
1073 | * peeled value for a reference, we will use it. | |
1074 | * | |
1075 | * peeled: | |
1076 | * | |
1077 | * References under "refs/tags/", if they *can* be peeled, *are* | |
1078 | * peeled in this file. References outside of "refs/tags/" are | |
1079 | * probably not peeled even if they could have been, but if we find | |
1080 | * a peeled value for such a reference we will use it. | |
1081 | * | |
1082 | * fully-peeled: | |
1083 | * | |
1084 | * All references in the file that can be peeled are peeled. | |
1085 | * Inversely (and this is more important), any references in the | |
1086 | * file for which no peeled value is recorded is not peelable. This | |
1087 | * trait should typically be written alongside "peeled" for | |
1088 | * compatibility with older clients, but we do not require it | |
1089 | * (i.e., "peeled" is a no-op if "fully-peeled" is set). | |
1090 | */ | |
1091 | static void read_packed_refs(FILE *f, struct ref_dir *dir) | |
1092 | { | |
1093 | struct ref_entry *last = NULL; | |
1094 | char refline[PATH_MAX]; | |
1095 | enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; | |
1096 | ||
1097 | while (fgets(refline, sizeof(refline), f)) { | |
1098 | unsigned char sha1[20]; | |
1099 | const char *refname; | |
1100 | static const char header[] = "# pack-refs with:"; | |
1101 | ||
1102 | if (!strncmp(refline, header, sizeof(header)-1)) { | |
1103 | const char *traits = refline + sizeof(header) - 1; | |
1104 | if (strstr(traits, " fully-peeled ")) | |
1105 | peeled = PEELED_FULLY; | |
1106 | else if (strstr(traits, " peeled ")) | |
1107 | peeled = PEELED_TAGS; | |
1108 | /* perhaps other traits later as well */ | |
1109 | continue; | |
1110 | } | |
1111 | ||
1112 | refname = parse_ref_line(refline, sha1); | |
1113 | if (refname) { | |
1114 | last = create_ref_entry(refname, sha1, REF_ISPACKED, 1); | |
1115 | if (peeled == PEELED_FULLY || | |
1116 | (peeled == PEELED_TAGS && starts_with(refname, "refs/tags/"))) | |
1117 | last->flag |= REF_KNOWS_PEELED; | |
1118 | add_ref(dir, last); | |
1119 | continue; | |
1120 | } | |
1121 | if (last && | |
1122 | refline[0] == '^' && | |
1123 | strlen(refline) == PEELED_LINE_LENGTH && | |
1124 | refline[PEELED_LINE_LENGTH - 1] == '\n' && | |
1125 | !get_sha1_hex(refline + 1, sha1)) { | |
1126 | hashcpy(last->u.value.peeled, sha1); | |
1127 | /* | |
1128 | * Regardless of what the file header said, | |
1129 | * we definitely know the value of *this* | |
1130 | * reference: | |
1131 | */ | |
1132 | last->flag |= REF_KNOWS_PEELED; | |
1133 | } | |
1134 | } | |
1135 | } | |
1136 | ||
1137 | /* | |
1138 | * Get the packed_ref_cache for the specified ref_cache, creating it | |
1139 | * if necessary. | |
1140 | */ | |
1141 | static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs) | |
1142 | { | |
1143 | const char *packed_refs_file; | |
1144 | ||
1145 | if (*refs->name) | |
1146 | packed_refs_file = git_path_submodule(refs->name, "packed-refs"); | |
1147 | else | |
1148 | packed_refs_file = git_path("packed-refs"); | |
1149 | ||
1150 | if (refs->packed && | |
1151 | !stat_validity_check(&refs->packed->validity, packed_refs_file)) | |
1152 | clear_packed_ref_cache(refs); | |
1153 | ||
1154 | if (!refs->packed) { | |
1155 | FILE *f; | |
1156 | ||
1157 | refs->packed = xcalloc(1, sizeof(*refs->packed)); | |
1158 | acquire_packed_ref_cache(refs->packed); | |
1159 | refs->packed->root = create_dir_entry(refs, "", 0, 0); | |
1160 | f = fopen(packed_refs_file, "r"); | |
1161 | if (f) { | |
1162 | stat_validity_update(&refs->packed->validity, fileno(f)); | |
1163 | read_packed_refs(f, get_ref_dir(refs->packed->root)); | |
1164 | fclose(f); | |
1165 | } | |
1166 | } | |
1167 | return refs->packed; | |
1168 | } | |
1169 | ||
1170 | static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache) | |
1171 | { | |
1172 | return get_ref_dir(packed_ref_cache->root); | |
1173 | } | |
1174 | ||
1175 | static struct ref_dir *get_packed_refs(struct ref_cache *refs) | |
1176 | { | |
1177 | return get_packed_ref_dir(get_packed_ref_cache(refs)); | |
1178 | } | |
1179 | ||
1180 | void add_packed_ref(const char *refname, const unsigned char *sha1) | |
1181 | { | |
1182 | struct packed_ref_cache *packed_ref_cache = | |
1183 | get_packed_ref_cache(&ref_cache); | |
1184 | ||
1185 | if (!packed_ref_cache->lock) | |
1186 | die("internal error: packed refs not locked"); | |
1187 | add_ref(get_packed_ref_dir(packed_ref_cache), | |
1188 | create_ref_entry(refname, sha1, REF_ISPACKED, 1)); | |
1189 | } | |
1190 | ||
1191 | /* | |
1192 | * Read the loose references from the namespace dirname into dir | |
1193 | * (without recursing). dirname must end with '/'. dir must be the | |
1194 | * directory entry corresponding to dirname. | |
1195 | */ | |
1196 | static void read_loose_refs(const char *dirname, struct ref_dir *dir) | |
1197 | { | |
1198 | struct ref_cache *refs = dir->ref_cache; | |
1199 | DIR *d; | |
1200 | const char *path; | |
1201 | struct dirent *de; | |
1202 | int dirnamelen = strlen(dirname); | |
1203 | struct strbuf refname; | |
1204 | ||
1205 | if (*refs->name) | |
1206 | path = git_path_submodule(refs->name, "%s", dirname); | |
1207 | else | |
1208 | path = git_path("%s", dirname); | |
1209 | ||
1210 | d = opendir(path); | |
1211 | if (!d) | |
1212 | return; | |
1213 | ||
1214 | strbuf_init(&refname, dirnamelen + 257); | |
1215 | strbuf_add(&refname, dirname, dirnamelen); | |
1216 | ||
1217 | while ((de = readdir(d)) != NULL) { | |
1218 | unsigned char sha1[20]; | |
1219 | struct stat st; | |
1220 | int flag; | |
1221 | const char *refdir; | |
1222 | ||
1223 | if (de->d_name[0] == '.') | |
1224 | continue; | |
1225 | if (ends_with(de->d_name, ".lock")) | |
1226 | continue; | |
1227 | strbuf_addstr(&refname, de->d_name); | |
1228 | refdir = *refs->name | |
1229 | ? git_path_submodule(refs->name, "%s", refname.buf) | |
1230 | : git_path("%s", refname.buf); | |
1231 | if (stat(refdir, &st) < 0) { | |
1232 | ; /* silently ignore */ | |
1233 | } else if (S_ISDIR(st.st_mode)) { | |
1234 | strbuf_addch(&refname, '/'); | |
1235 | add_entry_to_dir(dir, | |
1236 | create_dir_entry(refs, refname.buf, | |
1237 | refname.len, 1)); | |
1238 | } else { | |
1239 | if (*refs->name) { | |
1240 | hashclr(sha1); | |
1241 | flag = 0; | |
1242 | if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) { | |
1243 | hashclr(sha1); | |
1244 | flag |= REF_ISBROKEN; | |
1245 | } | |
1246 | } else if (read_ref_full(refname.buf, | |
1247 | RESOLVE_REF_READING, | |
1248 | sha1, &flag)) { | |
1249 | hashclr(sha1); | |
1250 | flag |= REF_ISBROKEN; | |
1251 | } | |
1252 | add_entry_to_dir(dir, | |
1253 | create_ref_entry(refname.buf, sha1, flag, 1)); | |
1254 | } | |
1255 | strbuf_setlen(&refname, dirnamelen); | |
1256 | } | |
1257 | strbuf_release(&refname); | |
1258 | closedir(d); | |
1259 | } | |
1260 | ||
1261 | static struct ref_dir *get_loose_refs(struct ref_cache *refs) | |
1262 | { | |
1263 | if (!refs->loose) { | |
1264 | /* | |
1265 | * Mark the top-level directory complete because we | |
1266 | * are about to read the only subdirectory that can | |
1267 | * hold references: | |
1268 | */ | |
1269 | refs->loose = create_dir_entry(refs, "", 0, 0); | |
1270 | /* | |
1271 | * Create an incomplete entry for "refs/": | |
1272 | */ | |
1273 | add_entry_to_dir(get_ref_dir(refs->loose), | |
1274 | create_dir_entry(refs, "refs/", 5, 1)); | |
1275 | } | |
1276 | return get_ref_dir(refs->loose); | |
1277 | } | |
1278 | ||
1279 | /* We allow "recursive" symbolic refs. Only within reason, though */ | |
1280 | #define MAXDEPTH 5 | |
1281 | #define MAXREFLEN (1024) | |
1282 | ||
1283 | /* | |
1284 | * Called by resolve_gitlink_ref_recursive() after it failed to read | |
1285 | * from the loose refs in ref_cache refs. Find <refname> in the | |
1286 | * packed-refs file for the submodule. | |
1287 | */ | |
1288 | static int resolve_gitlink_packed_ref(struct ref_cache *refs, | |
1289 | const char *refname, unsigned char *sha1) | |
1290 | { | |
1291 | struct ref_entry *ref; | |
1292 | struct ref_dir *dir = get_packed_refs(refs); | |
1293 | ||
1294 | ref = find_ref(dir, refname); | |
1295 | if (ref == NULL) | |
1296 | return -1; | |
1297 | ||
1298 | hashcpy(sha1, ref->u.value.sha1); | |
1299 | return 0; | |
1300 | } | |
1301 | ||
1302 | static int resolve_gitlink_ref_recursive(struct ref_cache *refs, | |
1303 | const char *refname, unsigned char *sha1, | |
1304 | int recursion) | |
1305 | { | |
1306 | int fd, len; | |
1307 | char buffer[128], *p; | |
1308 | char *path; | |
1309 | ||
1310 | if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN) | |
1311 | return -1; | |
1312 | path = *refs->name | |
1313 | ? git_path_submodule(refs->name, "%s", refname) | |
1314 | : git_path("%s", refname); | |
1315 | fd = open(path, O_RDONLY); | |
1316 | if (fd < 0) | |
1317 | return resolve_gitlink_packed_ref(refs, refname, sha1); | |
1318 | ||
1319 | len = read(fd, buffer, sizeof(buffer)-1); | |
1320 | close(fd); | |
1321 | if (len < 0) | |
1322 | return -1; | |
1323 | while (len && isspace(buffer[len-1])) | |
1324 | len--; | |
1325 | buffer[len] = 0; | |
1326 | ||
1327 | /* Was it a detached head or an old-fashioned symlink? */ | |
1328 | if (!get_sha1_hex(buffer, sha1)) | |
1329 | return 0; | |
1330 | ||
1331 | /* Symref? */ | |
1332 | if (strncmp(buffer, "ref:", 4)) | |
1333 | return -1; | |
1334 | p = buffer + 4; | |
1335 | while (isspace(*p)) | |
1336 | p++; | |
1337 | ||
1338 | return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1); | |
1339 | } | |
1340 | ||
1341 | int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1) | |
1342 | { | |
1343 | int len = strlen(path), retval; | |
1344 | char *submodule; | |
1345 | struct ref_cache *refs; | |
1346 | ||
1347 | while (len && path[len-1] == '/') | |
1348 | len--; | |
1349 | if (!len) | |
1350 | return -1; | |
1351 | submodule = xstrndup(path, len); | |
1352 | refs = get_ref_cache(submodule); | |
1353 | free(submodule); | |
1354 | ||
1355 | retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0); | |
1356 | return retval; | |
1357 | } | |
1358 | ||
1359 | /* | |
1360 | * Return the ref_entry for the given refname from the packed | |
1361 | * references. If it does not exist, return NULL. | |
1362 | */ | |
1363 | static struct ref_entry *get_packed_ref(const char *refname) | |
1364 | { | |
1365 | return find_ref(get_packed_refs(&ref_cache), refname); | |
1366 | } | |
1367 | ||
1368 | /* | |
1369 | * A loose ref file doesn't exist; check for a packed ref. The | |
1370 | * options are forwarded from resolve_safe_unsafe(). | |
1371 | */ | |
1372 | static const char *handle_missing_loose_ref(const char *refname, | |
1373 | int resolve_flags, | |
1374 | unsigned char *sha1, | |
1375 | int *flags) | |
1376 | { | |
1377 | struct ref_entry *entry; | |
1378 | ||
1379 | /* | |
1380 | * The loose reference file does not exist; check for a packed | |
1381 | * reference. | |
1382 | */ | |
1383 | entry = get_packed_ref(refname); | |
1384 | if (entry) { | |
1385 | hashcpy(sha1, entry->u.value.sha1); | |
1386 | if (flags) | |
1387 | *flags |= REF_ISPACKED; | |
1388 | return refname; | |
1389 | } | |
1390 | /* The reference is not a packed reference, either. */ | |
1391 | if (resolve_flags & RESOLVE_REF_READING) { | |
1392 | return NULL; | |
1393 | } else { | |
1394 | hashclr(sha1); | |
1395 | return refname; | |
1396 | } | |
1397 | } | |
1398 | ||
1399 | /* This function needs to return a meaningful errno on failure */ | |
1400 | const char *resolve_ref_unsafe(const char *refname, int resolve_flags, unsigned char *sha1, int *flags) | |
1401 | { | |
1402 | int depth = MAXDEPTH; | |
1403 | ssize_t len; | |
1404 | char buffer[256]; | |
1405 | static char refname_buffer[256]; | |
1406 | ||
1407 | if (flags) | |
1408 | *flags = 0; | |
1409 | ||
1410 | if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { | |
1411 | errno = EINVAL; | |
1412 | return NULL; | |
1413 | } | |
1414 | for (;;) { | |
1415 | char path[PATH_MAX]; | |
1416 | struct stat st; | |
1417 | char *buf; | |
1418 | int fd; | |
1419 | ||
1420 | if (--depth < 0) { | |
1421 | errno = ELOOP; | |
1422 | return NULL; | |
1423 | } | |
1424 | ||
1425 | git_snpath(path, sizeof(path), "%s", refname); | |
1426 | ||
1427 | /* | |
1428 | * We might have to loop back here to avoid a race | |
1429 | * condition: first we lstat() the file, then we try | |
1430 | * to read it as a link or as a file. But if somebody | |
1431 | * changes the type of the file (file <-> directory | |
1432 | * <-> symlink) between the lstat() and reading, then | |
1433 | * we don't want to report that as an error but rather | |
1434 | * try again starting with the lstat(). | |
1435 | */ | |
1436 | stat_ref: | |
1437 | if (lstat(path, &st) < 0) { | |
1438 | if (errno == ENOENT) | |
1439 | return handle_missing_loose_ref(refname, | |
1440 | resolve_flags, sha1, flags); | |
1441 | else | |
1442 | return NULL; | |
1443 | } | |
1444 | ||
1445 | /* Follow "normalized" - ie "refs/.." symlinks by hand */ | |
1446 | if (S_ISLNK(st.st_mode)) { | |
1447 | len = readlink(path, buffer, sizeof(buffer)-1); | |
1448 | if (len < 0) { | |
1449 | if (errno == ENOENT || errno == EINVAL) | |
1450 | /* inconsistent with lstat; retry */ | |
1451 | goto stat_ref; | |
1452 | else | |
1453 | return NULL; | |
1454 | } | |
1455 | buffer[len] = 0; | |
1456 | if (starts_with(buffer, "refs/") && | |
1457 | !check_refname_format(buffer, 0)) { | |
1458 | strcpy(refname_buffer, buffer); | |
1459 | refname = refname_buffer; | |
1460 | if (flags) | |
1461 | *flags |= REF_ISSYMREF; | |
1462 | if (resolve_flags & RESOLVE_REF_NO_RECURSE) { | |
1463 | hashclr(sha1); | |
1464 | return refname; | |
1465 | } | |
1466 | continue; | |
1467 | } | |
1468 | } | |
1469 | ||
1470 | /* Is it a directory? */ | |
1471 | if (S_ISDIR(st.st_mode)) { | |
1472 | errno = EISDIR; | |
1473 | return NULL; | |
1474 | } | |
1475 | ||
1476 | /* | |
1477 | * Anything else, just open it and try to use it as | |
1478 | * a ref | |
1479 | */ | |
1480 | fd = open(path, O_RDONLY); | |
1481 | if (fd < 0) { | |
1482 | if (errno == ENOENT) | |
1483 | /* inconsistent with lstat; retry */ | |
1484 | goto stat_ref; | |
1485 | else | |
1486 | return NULL; | |
1487 | } | |
1488 | len = read_in_full(fd, buffer, sizeof(buffer)-1); | |
1489 | if (len < 0) { | |
1490 | int save_errno = errno; | |
1491 | close(fd); | |
1492 | errno = save_errno; | |
1493 | return NULL; | |
1494 | } | |
1495 | close(fd); | |
1496 | while (len && isspace(buffer[len-1])) | |
1497 | len--; | |
1498 | buffer[len] = '\0'; | |
1499 | ||
1500 | /* | |
1501 | * Is it a symbolic ref? | |
1502 | */ | |
1503 | if (!starts_with(buffer, "ref:")) { | |
1504 | /* | |
1505 | * Please note that FETCH_HEAD has a second | |
1506 | * line containing other data. | |
1507 | */ | |
1508 | if (get_sha1_hex(buffer, sha1) || | |
1509 | (buffer[40] != '\0' && !isspace(buffer[40]))) { | |
1510 | if (flags) | |
1511 | *flags |= REF_ISBROKEN; | |
1512 | errno = EINVAL; | |
1513 | return NULL; | |
1514 | } | |
1515 | return refname; | |
1516 | } | |
1517 | if (flags) | |
1518 | *flags |= REF_ISSYMREF; | |
1519 | buf = buffer + 4; | |
1520 | while (isspace(*buf)) | |
1521 | buf++; | |
1522 | refname = strcpy(refname_buffer, buf); | |
1523 | if (resolve_flags & RESOLVE_REF_NO_RECURSE) { | |
1524 | hashclr(sha1); | |
1525 | return refname; | |
1526 | } | |
1527 | if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) { | |
1528 | if (flags) | |
1529 | *flags |= REF_ISBROKEN; | |
1530 | errno = EINVAL; | |
1531 | return NULL; | |
1532 | } | |
1533 | } | |
1534 | } | |
1535 | ||
1536 | char *resolve_refdup(const char *ref, int resolve_flags, unsigned char *sha1, int *flags) | |
1537 | { | |
1538 | const char *ret = resolve_ref_unsafe(ref, resolve_flags, sha1, flags); | |
1539 | return ret ? xstrdup(ret) : NULL; | |
1540 | } | |
1541 | ||
1542 | /* The argument to filter_refs */ | |
1543 | struct ref_filter { | |
1544 | const char *pattern; | |
1545 | each_ref_fn *fn; | |
1546 | void *cb_data; | |
1547 | }; | |
1548 | ||
1549 | int read_ref_full(const char *refname, int resolve_flags, unsigned char *sha1, int *flags) | |
1550 | { | |
1551 | if (resolve_ref_unsafe(refname, resolve_flags, sha1, flags)) | |
1552 | return 0; | |
1553 | return -1; | |
1554 | } | |
1555 | ||
1556 | int read_ref(const char *refname, unsigned char *sha1) | |
1557 | { | |
1558 | return read_ref_full(refname, RESOLVE_REF_READING, sha1, NULL); | |
1559 | } | |
1560 | ||
1561 | int ref_exists(const char *refname) | |
1562 | { | |
1563 | unsigned char sha1[20]; | |
1564 | return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, sha1, NULL); | |
1565 | } | |
1566 | ||
1567 | static int filter_refs(const char *refname, const unsigned char *sha1, int flags, | |
1568 | void *data) | |
1569 | { | |
1570 | struct ref_filter *filter = (struct ref_filter *)data; | |
1571 | if (wildmatch(filter->pattern, refname, 0, NULL)) | |
1572 | return 0; | |
1573 | return filter->fn(refname, sha1, flags, filter->cb_data); | |
1574 | } | |
1575 | ||
1576 | enum peel_status { | |
1577 | /* object was peeled successfully: */ | |
1578 | PEEL_PEELED = 0, | |
1579 | ||
1580 | /* | |
1581 | * object cannot be peeled because the named object (or an | |
1582 | * object referred to by a tag in the peel chain), does not | |
1583 | * exist. | |
1584 | */ | |
1585 | PEEL_INVALID = -1, | |
1586 | ||
1587 | /* object cannot be peeled because it is not a tag: */ | |
1588 | PEEL_NON_TAG = -2, | |
1589 | ||
1590 | /* ref_entry contains no peeled value because it is a symref: */ | |
1591 | PEEL_IS_SYMREF = -3, | |
1592 | ||
1593 | /* | |
1594 | * ref_entry cannot be peeled because it is broken (i.e., the | |
1595 | * symbolic reference cannot even be resolved to an object | |
1596 | * name): | |
1597 | */ | |
1598 | PEEL_BROKEN = -4 | |
1599 | }; | |
1600 | ||
1601 | /* | |
1602 | * Peel the named object; i.e., if the object is a tag, resolve the | |
1603 | * tag recursively until a non-tag is found. If successful, store the | |
1604 | * result to sha1 and return PEEL_PEELED. If the object is not a tag | |
1605 | * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively, | |
1606 | * and leave sha1 unchanged. | |
1607 | */ | |
1608 | static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1) | |
1609 | { | |
1610 | struct object *o = lookup_unknown_object(name); | |
1611 | ||
1612 | if (o->type == OBJ_NONE) { | |
1613 | int type = sha1_object_info(name, NULL); | |
1614 | if (type < 0 || !object_as_type(o, type, 0)) | |
1615 | return PEEL_INVALID; | |
1616 | } | |
1617 | ||
1618 | if (o->type != OBJ_TAG) | |
1619 | return PEEL_NON_TAG; | |
1620 | ||
1621 | o = deref_tag_noverify(o); | |
1622 | if (!o) | |
1623 | return PEEL_INVALID; | |
1624 | ||
1625 | hashcpy(sha1, o->sha1); | |
1626 | return PEEL_PEELED; | |
1627 | } | |
1628 | ||
1629 | /* | |
1630 | * Peel the entry (if possible) and return its new peel_status. If | |
1631 | * repeel is true, re-peel the entry even if there is an old peeled | |
1632 | * value that is already stored in it. | |
1633 | * | |
1634 | * It is OK to call this function with a packed reference entry that | |
1635 | * might be stale and might even refer to an object that has since | |
1636 | * been garbage-collected. In such a case, if the entry has | |
1637 | * REF_KNOWS_PEELED then leave the status unchanged and return | |
1638 | * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID. | |
1639 | */ | |
1640 | static enum peel_status peel_entry(struct ref_entry *entry, int repeel) | |
1641 | { | |
1642 | enum peel_status status; | |
1643 | ||
1644 | if (entry->flag & REF_KNOWS_PEELED) { | |
1645 | if (repeel) { | |
1646 | entry->flag &= ~REF_KNOWS_PEELED; | |
1647 | hashclr(entry->u.value.peeled); | |
1648 | } else { | |
1649 | return is_null_sha1(entry->u.value.peeled) ? | |
1650 | PEEL_NON_TAG : PEEL_PEELED; | |
1651 | } | |
1652 | } | |
1653 | if (entry->flag & REF_ISBROKEN) | |
1654 | return PEEL_BROKEN; | |
1655 | if (entry->flag & REF_ISSYMREF) | |
1656 | return PEEL_IS_SYMREF; | |
1657 | ||
1658 | status = peel_object(entry->u.value.sha1, entry->u.value.peeled); | |
1659 | if (status == PEEL_PEELED || status == PEEL_NON_TAG) | |
1660 | entry->flag |= REF_KNOWS_PEELED; | |
1661 | return status; | |
1662 | } | |
1663 | ||
1664 | int peel_ref(const char *refname, unsigned char *sha1) | |
1665 | { | |
1666 | int flag; | |
1667 | unsigned char base[20]; | |
1668 | ||
1669 | if (current_ref && (current_ref->name == refname | |
1670 | || !strcmp(current_ref->name, refname))) { | |
1671 | if (peel_entry(current_ref, 0)) | |
1672 | return -1; | |
1673 | hashcpy(sha1, current_ref->u.value.peeled); | |
1674 | return 0; | |
1675 | } | |
1676 | ||
1677 | if (read_ref_full(refname, RESOLVE_REF_READING, base, &flag)) | |
1678 | return -1; | |
1679 | ||
1680 | /* | |
1681 | * If the reference is packed, read its ref_entry from the | |
1682 | * cache in the hope that we already know its peeled value. | |
1683 | * We only try this optimization on packed references because | |
1684 | * (a) forcing the filling of the loose reference cache could | |
1685 | * be expensive and (b) loose references anyway usually do not | |
1686 | * have REF_KNOWS_PEELED. | |
1687 | */ | |
1688 | if (flag & REF_ISPACKED) { | |
1689 | struct ref_entry *r = get_packed_ref(refname); | |
1690 | if (r) { | |
1691 | if (peel_entry(r, 0)) | |
1692 | return -1; | |
1693 | hashcpy(sha1, r->u.value.peeled); | |
1694 | return 0; | |
1695 | } | |
1696 | } | |
1697 | ||
1698 | return peel_object(base, sha1); | |
1699 | } | |
1700 | ||
1701 | struct warn_if_dangling_data { | |
1702 | FILE *fp; | |
1703 | const char *refname; | |
1704 | const struct string_list *refnames; | |
1705 | const char *msg_fmt; | |
1706 | }; | |
1707 | ||
1708 | static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1, | |
1709 | int flags, void *cb_data) | |
1710 | { | |
1711 | struct warn_if_dangling_data *d = cb_data; | |
1712 | const char *resolves_to; | |
1713 | unsigned char junk[20]; | |
1714 | ||
1715 | if (!(flags & REF_ISSYMREF)) | |
1716 | return 0; | |
1717 | ||
1718 | resolves_to = resolve_ref_unsafe(refname, 0, junk, NULL); | |
1719 | if (!resolves_to | |
1720 | || (d->refname | |
1721 | ? strcmp(resolves_to, d->refname) | |
1722 | : !string_list_has_string(d->refnames, resolves_to))) { | |
1723 | return 0; | |
1724 | } | |
1725 | ||
1726 | fprintf(d->fp, d->msg_fmt, refname); | |
1727 | fputc('\n', d->fp); | |
1728 | return 0; | |
1729 | } | |
1730 | ||
1731 | void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname) | |
1732 | { | |
1733 | struct warn_if_dangling_data data; | |
1734 | ||
1735 | data.fp = fp; | |
1736 | data.refname = refname; | |
1737 | data.refnames = NULL; | |
1738 | data.msg_fmt = msg_fmt; | |
1739 | for_each_rawref(warn_if_dangling_symref, &data); | |
1740 | } | |
1741 | ||
1742 | void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames) | |
1743 | { | |
1744 | struct warn_if_dangling_data data; | |
1745 | ||
1746 | data.fp = fp; | |
1747 | data.refname = NULL; | |
1748 | data.refnames = refnames; | |
1749 | data.msg_fmt = msg_fmt; | |
1750 | for_each_rawref(warn_if_dangling_symref, &data); | |
1751 | } | |
1752 | ||
1753 | /* | |
1754 | * Call fn for each reference in the specified ref_cache, omitting | |
1755 | * references not in the containing_dir of base. fn is called for all | |
1756 | * references, including broken ones. If fn ever returns a non-zero | |
1757 | * value, stop the iteration and return that value; otherwise, return | |
1758 | * 0. | |
1759 | */ | |
1760 | static int do_for_each_entry(struct ref_cache *refs, const char *base, | |
1761 | each_ref_entry_fn fn, void *cb_data) | |
1762 | { | |
1763 | struct packed_ref_cache *packed_ref_cache; | |
1764 | struct ref_dir *loose_dir; | |
1765 | struct ref_dir *packed_dir; | |
1766 | int retval = 0; | |
1767 | ||
1768 | /* | |
1769 | * We must make sure that all loose refs are read before accessing the | |
1770 | * packed-refs file; this avoids a race condition in which loose refs | |
1771 | * are migrated to the packed-refs file by a simultaneous process, but | |
1772 | * our in-memory view is from before the migration. get_packed_ref_cache() | |
1773 | * takes care of making sure our view is up to date with what is on | |
1774 | * disk. | |
1775 | */ | |
1776 | loose_dir = get_loose_refs(refs); | |
1777 | if (base && *base) { | |
1778 | loose_dir = find_containing_dir(loose_dir, base, 0); | |
1779 | } | |
1780 | if (loose_dir) | |
1781 | prime_ref_dir(loose_dir); | |
1782 | ||
1783 | packed_ref_cache = get_packed_ref_cache(refs); | |
1784 | acquire_packed_ref_cache(packed_ref_cache); | |
1785 | packed_dir = get_packed_ref_dir(packed_ref_cache); | |
1786 | if (base && *base) { | |
1787 | packed_dir = find_containing_dir(packed_dir, base, 0); | |
1788 | } | |
1789 | ||
1790 | if (packed_dir && loose_dir) { | |
1791 | sort_ref_dir(packed_dir); | |
1792 | sort_ref_dir(loose_dir); | |
1793 | retval = do_for_each_entry_in_dirs( | |
1794 | packed_dir, loose_dir, fn, cb_data); | |
1795 | } else if (packed_dir) { | |
1796 | sort_ref_dir(packed_dir); | |
1797 | retval = do_for_each_entry_in_dir( | |
1798 | packed_dir, 0, fn, cb_data); | |
1799 | } else if (loose_dir) { | |
1800 | sort_ref_dir(loose_dir); | |
1801 | retval = do_for_each_entry_in_dir( | |
1802 | loose_dir, 0, fn, cb_data); | |
1803 | } | |
1804 | ||
1805 | release_packed_ref_cache(packed_ref_cache); | |
1806 | return retval; | |
1807 | } | |
1808 | ||
1809 | /* | |
1810 | * Call fn for each reference in the specified ref_cache for which the | |
1811 | * refname begins with base. If trim is non-zero, then trim that many | |
1812 | * characters off the beginning of each refname before passing the | |
1813 | * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include | |
1814 | * broken references in the iteration. If fn ever returns a non-zero | |
1815 | * value, stop the iteration and return that value; otherwise, return | |
1816 | * 0. | |
1817 | */ | |
1818 | static int do_for_each_ref(struct ref_cache *refs, const char *base, | |
1819 | each_ref_fn fn, int trim, int flags, void *cb_data) | |
1820 | { | |
1821 | struct ref_entry_cb data; | |
1822 | data.base = base; | |
1823 | data.trim = trim; | |
1824 | data.flags = flags; | |
1825 | data.fn = fn; | |
1826 | data.cb_data = cb_data; | |
1827 | ||
1828 | return do_for_each_entry(refs, base, do_one_ref, &data); | |
1829 | } | |
1830 | ||
1831 | static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data) | |
1832 | { | |
1833 | unsigned char sha1[20]; | |
1834 | int flag; | |
1835 | ||
1836 | if (submodule) { | |
1837 | if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0) | |
1838 | return fn("HEAD", sha1, 0, cb_data); | |
1839 | ||
1840 | return 0; | |
1841 | } | |
1842 | ||
1843 | if (!read_ref_full("HEAD", RESOLVE_REF_READING, sha1, &flag)) | |
1844 | return fn("HEAD", sha1, flag, cb_data); | |
1845 | ||
1846 | return 0; | |
1847 | } | |
1848 | ||
1849 | int head_ref(each_ref_fn fn, void *cb_data) | |
1850 | { | |
1851 | return do_head_ref(NULL, fn, cb_data); | |
1852 | } | |
1853 | ||
1854 | int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) | |
1855 | { | |
1856 | return do_head_ref(submodule, fn, cb_data); | |
1857 | } | |
1858 | ||
1859 | int for_each_ref(each_ref_fn fn, void *cb_data) | |
1860 | { | |
1861 | return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data); | |
1862 | } | |
1863 | ||
1864 | int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) | |
1865 | { | |
1866 | return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data); | |
1867 | } | |
1868 | ||
1869 | int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data) | |
1870 | { | |
1871 | return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data); | |
1872 | } | |
1873 | ||
1874 | int for_each_ref_in_submodule(const char *submodule, const char *prefix, | |
1875 | each_ref_fn fn, void *cb_data) | |
1876 | { | |
1877 | return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data); | |
1878 | } | |
1879 | ||
1880 | int for_each_tag_ref(each_ref_fn fn, void *cb_data) | |
1881 | { | |
1882 | return for_each_ref_in("refs/tags/", fn, cb_data); | |
1883 | } | |
1884 | ||
1885 | int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) | |
1886 | { | |
1887 | return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data); | |
1888 | } | |
1889 | ||
1890 | int for_each_branch_ref(each_ref_fn fn, void *cb_data) | |
1891 | { | |
1892 | return for_each_ref_in("refs/heads/", fn, cb_data); | |
1893 | } | |
1894 | ||
1895 | int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) | |
1896 | { | |
1897 | return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data); | |
1898 | } | |
1899 | ||
1900 | int for_each_remote_ref(each_ref_fn fn, void *cb_data) | |
1901 | { | |
1902 | return for_each_ref_in("refs/remotes/", fn, cb_data); | |
1903 | } | |
1904 | ||
1905 | int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) | |
1906 | { | |
1907 | return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data); | |
1908 | } | |
1909 | ||
1910 | int for_each_replace_ref(each_ref_fn fn, void *cb_data) | |
1911 | { | |
1912 | return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data); | |
1913 | } | |
1914 | ||
1915 | int head_ref_namespaced(each_ref_fn fn, void *cb_data) | |
1916 | { | |
1917 | struct strbuf buf = STRBUF_INIT; | |
1918 | int ret = 0; | |
1919 | unsigned char sha1[20]; | |
1920 | int flag; | |
1921 | ||
1922 | strbuf_addf(&buf, "%sHEAD", get_git_namespace()); | |
1923 | if (!read_ref_full(buf.buf, RESOLVE_REF_READING, sha1, &flag)) | |
1924 | ret = fn(buf.buf, sha1, flag, cb_data); | |
1925 | strbuf_release(&buf); | |
1926 | ||
1927 | return ret; | |
1928 | } | |
1929 | ||
1930 | int for_each_namespaced_ref(each_ref_fn fn, void *cb_data) | |
1931 | { | |
1932 | struct strbuf buf = STRBUF_INIT; | |
1933 | int ret; | |
1934 | strbuf_addf(&buf, "%srefs/", get_git_namespace()); | |
1935 | ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data); | |
1936 | strbuf_release(&buf); | |
1937 | return ret; | |
1938 | } | |
1939 | ||
1940 | int for_each_glob_ref_in(each_ref_fn fn, const char *pattern, | |
1941 | const char *prefix, void *cb_data) | |
1942 | { | |
1943 | struct strbuf real_pattern = STRBUF_INIT; | |
1944 | struct ref_filter filter; | |
1945 | int ret; | |
1946 | ||
1947 | if (!prefix && !starts_with(pattern, "refs/")) | |
1948 | strbuf_addstr(&real_pattern, "refs/"); | |
1949 | else if (prefix) | |
1950 | strbuf_addstr(&real_pattern, prefix); | |
1951 | strbuf_addstr(&real_pattern, pattern); | |
1952 | ||
1953 | if (!has_glob_specials(pattern)) { | |
1954 | /* Append implied '/' '*' if not present. */ | |
1955 | if (real_pattern.buf[real_pattern.len - 1] != '/') | |
1956 | strbuf_addch(&real_pattern, '/'); | |
1957 | /* No need to check for '*', there is none. */ | |
1958 | strbuf_addch(&real_pattern, '*'); | |
1959 | } | |
1960 | ||
1961 | filter.pattern = real_pattern.buf; | |
1962 | filter.fn = fn; | |
1963 | filter.cb_data = cb_data; | |
1964 | ret = for_each_ref(filter_refs, &filter); | |
1965 | ||
1966 | strbuf_release(&real_pattern); | |
1967 | return ret; | |
1968 | } | |
1969 | ||
1970 | int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data) | |
1971 | { | |
1972 | return for_each_glob_ref_in(fn, pattern, NULL, cb_data); | |
1973 | } | |
1974 | ||
1975 | int for_each_rawref(each_ref_fn fn, void *cb_data) | |
1976 | { | |
1977 | return do_for_each_ref(&ref_cache, "", fn, 0, | |
1978 | DO_FOR_EACH_INCLUDE_BROKEN, cb_data); | |
1979 | } | |
1980 | ||
1981 | const char *prettify_refname(const char *name) | |
1982 | { | |
1983 | return name + ( | |
1984 | starts_with(name, "refs/heads/") ? 11 : | |
1985 | starts_with(name, "refs/tags/") ? 10 : | |
1986 | starts_with(name, "refs/remotes/") ? 13 : | |
1987 | 0); | |
1988 | } | |
1989 | ||
1990 | static const char *ref_rev_parse_rules[] = { | |
1991 | "%.*s", | |
1992 | "refs/%.*s", | |
1993 | "refs/tags/%.*s", | |
1994 | "refs/heads/%.*s", | |
1995 | "refs/remotes/%.*s", | |
1996 | "refs/remotes/%.*s/HEAD", | |
1997 | NULL | |
1998 | }; | |
1999 | ||
2000 | int refname_match(const char *abbrev_name, const char *full_name) | |
2001 | { | |
2002 | const char **p; | |
2003 | const int abbrev_name_len = strlen(abbrev_name); | |
2004 | ||
2005 | for (p = ref_rev_parse_rules; *p; p++) { | |
2006 | if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) { | |
2007 | return 1; | |
2008 | } | |
2009 | } | |
2010 | ||
2011 | return 0; | |
2012 | } | |
2013 | ||
2014 | /* This function should make sure errno is meaningful on error */ | |
2015 | static struct ref_lock *verify_lock(struct ref_lock *lock, | |
2016 | const unsigned char *old_sha1, int mustexist) | |
2017 | { | |
2018 | if (read_ref_full(lock->ref_name, | |
2019 | mustexist ? RESOLVE_REF_READING : 0, | |
2020 | lock->old_sha1, NULL)) { | |
2021 | int save_errno = errno; | |
2022 | error("Can't verify ref %s", lock->ref_name); | |
2023 | unlock_ref(lock); | |
2024 | errno = save_errno; | |
2025 | return NULL; | |
2026 | } | |
2027 | if (hashcmp(lock->old_sha1, old_sha1)) { | |
2028 | error("Ref %s is at %s but expected %s", lock->ref_name, | |
2029 | sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1)); | |
2030 | unlock_ref(lock); | |
2031 | errno = EBUSY; | |
2032 | return NULL; | |
2033 | } | |
2034 | return lock; | |
2035 | } | |
2036 | ||
2037 | static int remove_empty_directories(const char *file) | |
2038 | { | |
2039 | /* we want to create a file but there is a directory there; | |
2040 | * if that is an empty directory (or a directory that contains | |
2041 | * only empty directories), remove them. | |
2042 | */ | |
2043 | struct strbuf path; | |
2044 | int result, save_errno; | |
2045 | ||
2046 | strbuf_init(&path, 20); | |
2047 | strbuf_addstr(&path, file); | |
2048 | ||
2049 | result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY); | |
2050 | save_errno = errno; | |
2051 | ||
2052 | strbuf_release(&path); | |
2053 | errno = save_errno; | |
2054 | ||
2055 | return result; | |
2056 | } | |
2057 | ||
2058 | /* | |
2059 | * *string and *len will only be substituted, and *string returned (for | |
2060 | * later free()ing) if the string passed in is a magic short-hand form | |
2061 | * to name a branch. | |
2062 | */ | |
2063 | static char *substitute_branch_name(const char **string, int *len) | |
2064 | { | |
2065 | struct strbuf buf = STRBUF_INIT; | |
2066 | int ret = interpret_branch_name(*string, *len, &buf); | |
2067 | ||
2068 | if (ret == *len) { | |
2069 | size_t size; | |
2070 | *string = strbuf_detach(&buf, &size); | |
2071 | *len = size; | |
2072 | return (char *)*string; | |
2073 | } | |
2074 | ||
2075 | return NULL; | |
2076 | } | |
2077 | ||
2078 | int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref) | |
2079 | { | |
2080 | char *last_branch = substitute_branch_name(&str, &len); | |
2081 | const char **p, *r; | |
2082 | int refs_found = 0; | |
2083 | ||
2084 | *ref = NULL; | |
2085 | for (p = ref_rev_parse_rules; *p; p++) { | |
2086 | char fullref[PATH_MAX]; | |
2087 | unsigned char sha1_from_ref[20]; | |
2088 | unsigned char *this_result; | |
2089 | int flag; | |
2090 | ||
2091 | this_result = refs_found ? sha1_from_ref : sha1; | |
2092 | mksnpath(fullref, sizeof(fullref), *p, len, str); | |
2093 | r = resolve_ref_unsafe(fullref, RESOLVE_REF_READING, | |
2094 | this_result, &flag); | |
2095 | if (r) { | |
2096 | if (!refs_found++) | |
2097 | *ref = xstrdup(r); | |
2098 | if (!warn_ambiguous_refs) | |
2099 | break; | |
2100 | } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) { | |
2101 | warning("ignoring dangling symref %s.", fullref); | |
2102 | } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) { | |
2103 | warning("ignoring broken ref %s.", fullref); | |
2104 | } | |
2105 | } | |
2106 | free(last_branch); | |
2107 | return refs_found; | |
2108 | } | |
2109 | ||
2110 | int dwim_log(const char *str, int len, unsigned char *sha1, char **log) | |
2111 | { | |
2112 | char *last_branch = substitute_branch_name(&str, &len); | |
2113 | const char **p; | |
2114 | int logs_found = 0; | |
2115 | ||
2116 | *log = NULL; | |
2117 | for (p = ref_rev_parse_rules; *p; p++) { | |
2118 | unsigned char hash[20]; | |
2119 | char path[PATH_MAX]; | |
2120 | const char *ref, *it; | |
2121 | ||
2122 | mksnpath(path, sizeof(path), *p, len, str); | |
2123 | ref = resolve_ref_unsafe(path, RESOLVE_REF_READING, | |
2124 | hash, NULL); | |
2125 | if (!ref) | |
2126 | continue; | |
2127 | if (reflog_exists(path)) | |
2128 | it = path; | |
2129 | else if (strcmp(ref, path) && reflog_exists(ref)) | |
2130 | it = ref; | |
2131 | else | |
2132 | continue; | |
2133 | if (!logs_found++) { | |
2134 | *log = xstrdup(it); | |
2135 | hashcpy(sha1, hash); | |
2136 | } | |
2137 | if (!warn_ambiguous_refs) | |
2138 | break; | |
2139 | } | |
2140 | free(last_branch); | |
2141 | return logs_found; | |
2142 | } | |
2143 | ||
2144 | /* | |
2145 | * Locks a ref returning the lock on success and NULL on failure. | |
2146 | * On failure errno is set to something meaningful. | |
2147 | */ | |
2148 | static struct ref_lock *lock_ref_sha1_basic(const char *refname, | |
2149 | const unsigned char *old_sha1, | |
2150 | const struct string_list *skip, | |
2151 | int flags, int *type_p) | |
2152 | { | |
2153 | char *ref_file; | |
2154 | const char *orig_refname = refname; | |
2155 | struct ref_lock *lock; | |
2156 | int last_errno = 0; | |
2157 | int type, lflags; | |
2158 | int mustexist = (old_sha1 && !is_null_sha1(old_sha1)); | |
2159 | int resolve_flags = 0; | |
2160 | int missing = 0; | |
2161 | int attempts_remaining = 3; | |
2162 | ||
2163 | if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { | |
2164 | errno = EINVAL; | |
2165 | return NULL; | |
2166 | } | |
2167 | ||
2168 | lock = xcalloc(1, sizeof(struct ref_lock)); | |
2169 | lock->lock_fd = -1; | |
2170 | ||
2171 | if (mustexist) | |
2172 | resolve_flags |= RESOLVE_REF_READING; | |
2173 | if (flags & REF_NODEREF && flags & REF_DELETING) | |
2174 | resolve_flags |= RESOLVE_REF_NO_RECURSE; | |
2175 | ||
2176 | refname = resolve_ref_unsafe(refname, resolve_flags, | |
2177 | lock->old_sha1, &type); | |
2178 | if (!refname && errno == EISDIR) { | |
2179 | /* we are trying to lock foo but we used to | |
2180 | * have foo/bar which now does not exist; | |
2181 | * it is normal for the empty directory 'foo' | |
2182 | * to remain. | |
2183 | */ | |
2184 | ref_file = git_path("%s", orig_refname); | |
2185 | if (remove_empty_directories(ref_file)) { | |
2186 | last_errno = errno; | |
2187 | error("there are still refs under '%s'", orig_refname); | |
2188 | goto error_return; | |
2189 | } | |
2190 | refname = resolve_ref_unsafe(orig_refname, resolve_flags, | |
2191 | lock->old_sha1, &type); | |
2192 | } | |
2193 | if (type_p) | |
2194 | *type_p = type; | |
2195 | if (!refname) { | |
2196 | last_errno = errno; | |
2197 | error("unable to resolve reference %s: %s", | |
2198 | orig_refname, strerror(errno)); | |
2199 | goto error_return; | |
2200 | } | |
2201 | missing = is_null_sha1(lock->old_sha1); | |
2202 | /* When the ref did not exist and we are creating it, | |
2203 | * make sure there is no existing ref that is packed | |
2204 | * whose name begins with our refname, nor a ref whose | |
2205 | * name is a proper prefix of our refname. | |
2206 | */ | |
2207 | if (missing && | |
2208 | !is_refname_available(refname, skip, get_packed_refs(&ref_cache))) { | |
2209 | last_errno = ENOTDIR; | |
2210 | goto error_return; | |
2211 | } | |
2212 | ||
2213 | lock->lk = xcalloc(1, sizeof(struct lock_file)); | |
2214 | ||
2215 | lflags = 0; | |
2216 | if (flags & REF_NODEREF) { | |
2217 | refname = orig_refname; | |
2218 | lflags |= LOCK_NO_DEREF; | |
2219 | } | |
2220 | lock->ref_name = xstrdup(refname); | |
2221 | lock->orig_ref_name = xstrdup(orig_refname); | |
2222 | ref_file = git_path("%s", refname); | |
2223 | if (missing) | |
2224 | lock->force_write = 1; | |
2225 | if ((flags & REF_NODEREF) && (type & REF_ISSYMREF)) | |
2226 | lock->force_write = 1; | |
2227 | ||
2228 | retry: | |
2229 | switch (safe_create_leading_directories(ref_file)) { | |
2230 | case SCLD_OK: | |
2231 | break; /* success */ | |
2232 | case SCLD_VANISHED: | |
2233 | if (--attempts_remaining > 0) | |
2234 | goto retry; | |
2235 | /* fall through */ | |
2236 | default: | |
2237 | last_errno = errno; | |
2238 | error("unable to create directory for %s", ref_file); | |
2239 | goto error_return; | |
2240 | } | |
2241 | ||
2242 | lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags); | |
2243 | if (lock->lock_fd < 0) { | |
2244 | if (errno == ENOENT && --attempts_remaining > 0) | |
2245 | /* | |
2246 | * Maybe somebody just deleted one of the | |
2247 | * directories leading to ref_file. Try | |
2248 | * again: | |
2249 | */ | |
2250 | goto retry; | |
2251 | else | |
2252 | unable_to_lock_die(ref_file, errno); | |
2253 | } | |
2254 | return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock; | |
2255 | ||
2256 | error_return: | |
2257 | unlock_ref(lock); | |
2258 | errno = last_errno; | |
2259 | return NULL; | |
2260 | } | |
2261 | ||
2262 | struct ref_lock *lock_any_ref_for_update(const char *refname, | |
2263 | const unsigned char *old_sha1, | |
2264 | int flags, int *type_p) | |
2265 | { | |
2266 | return lock_ref_sha1_basic(refname, old_sha1, NULL, flags, type_p); | |
2267 | } | |
2268 | ||
2269 | /* | |
2270 | * Write an entry to the packed-refs file for the specified refname. | |
2271 | * If peeled is non-NULL, write it as the entry's peeled value. | |
2272 | */ | |
2273 | static void write_packed_entry(FILE *fh, char *refname, unsigned char *sha1, | |
2274 | unsigned char *peeled) | |
2275 | { | |
2276 | fprintf_or_die(fh, "%s %s\n", sha1_to_hex(sha1), refname); | |
2277 | if (peeled) | |
2278 | fprintf_or_die(fh, "^%s\n", sha1_to_hex(peeled)); | |
2279 | } | |
2280 | ||
2281 | /* | |
2282 | * An each_ref_entry_fn that writes the entry to a packed-refs file. | |
2283 | */ | |
2284 | static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data) | |
2285 | { | |
2286 | enum peel_status peel_status = peel_entry(entry, 0); | |
2287 | ||
2288 | if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG) | |
2289 | error("internal error: %s is not a valid packed reference!", | |
2290 | entry->name); | |
2291 | write_packed_entry(cb_data, entry->name, entry->u.value.sha1, | |
2292 | peel_status == PEEL_PEELED ? | |
2293 | entry->u.value.peeled : NULL); | |
2294 | return 0; | |
2295 | } | |
2296 | ||
2297 | /* This should return a meaningful errno on failure */ | |
2298 | int lock_packed_refs(int flags) | |
2299 | { | |
2300 | struct packed_ref_cache *packed_ref_cache; | |
2301 | ||
2302 | if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0) | |
2303 | return -1; | |
2304 | /* | |
2305 | * Get the current packed-refs while holding the lock. If the | |
2306 | * packed-refs file has been modified since we last read it, | |
2307 | * this will automatically invalidate the cache and re-read | |
2308 | * the packed-refs file. | |
2309 | */ | |
2310 | packed_ref_cache = get_packed_ref_cache(&ref_cache); | |
2311 | packed_ref_cache->lock = &packlock; | |
2312 | /* Increment the reference count to prevent it from being freed: */ | |
2313 | acquire_packed_ref_cache(packed_ref_cache); | |
2314 | return 0; | |
2315 | } | |
2316 | ||
2317 | /* | |
2318 | * Commit the packed refs changes. | |
2319 | * On error we must make sure that errno contains a meaningful value. | |
2320 | */ | |
2321 | int commit_packed_refs(void) | |
2322 | { | |
2323 | struct packed_ref_cache *packed_ref_cache = | |
2324 | get_packed_ref_cache(&ref_cache); | |
2325 | int error = 0; | |
2326 | int save_errno = 0; | |
2327 | FILE *out; | |
2328 | ||
2329 | if (!packed_ref_cache->lock) | |
2330 | die("internal error: packed-refs not locked"); | |
2331 | ||
2332 | out = fdopen_lock_file(packed_ref_cache->lock, "w"); | |
2333 | if (!out) | |
2334 | die_errno("unable to fdopen packed-refs descriptor"); | |
2335 | ||
2336 | fprintf_or_die(out, "%s", PACKED_REFS_HEADER); | |
2337 | do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache), | |
2338 | 0, write_packed_entry_fn, out); | |
2339 | ||
2340 | if (commit_lock_file(packed_ref_cache->lock)) { | |
2341 | save_errno = errno; | |
2342 | error = -1; | |
2343 | } | |
2344 | packed_ref_cache->lock = NULL; | |
2345 | release_packed_ref_cache(packed_ref_cache); | |
2346 | errno = save_errno; | |
2347 | return error; | |
2348 | } | |
2349 | ||
2350 | void rollback_packed_refs(void) | |
2351 | { | |
2352 | struct packed_ref_cache *packed_ref_cache = | |
2353 | get_packed_ref_cache(&ref_cache); | |
2354 | ||
2355 | if (!packed_ref_cache->lock) | |
2356 | die("internal error: packed-refs not locked"); | |
2357 | rollback_lock_file(packed_ref_cache->lock); | |
2358 | packed_ref_cache->lock = NULL; | |
2359 | release_packed_ref_cache(packed_ref_cache); | |
2360 | clear_packed_ref_cache(&ref_cache); | |
2361 | } | |
2362 | ||
2363 | struct ref_to_prune { | |
2364 | struct ref_to_prune *next; | |
2365 | unsigned char sha1[20]; | |
2366 | char name[FLEX_ARRAY]; | |
2367 | }; | |
2368 | ||
2369 | struct pack_refs_cb_data { | |
2370 | unsigned int flags; | |
2371 | struct ref_dir *packed_refs; | |
2372 | struct ref_to_prune *ref_to_prune; | |
2373 | }; | |
2374 | ||
2375 | /* | |
2376 | * An each_ref_entry_fn that is run over loose references only. If | |
2377 | * the loose reference can be packed, add an entry in the packed ref | |
2378 | * cache. If the reference should be pruned, also add it to | |
2379 | * ref_to_prune in the pack_refs_cb_data. | |
2380 | */ | |
2381 | static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data) | |
2382 | { | |
2383 | struct pack_refs_cb_data *cb = cb_data; | |
2384 | enum peel_status peel_status; | |
2385 | struct ref_entry *packed_entry; | |
2386 | int is_tag_ref = starts_with(entry->name, "refs/tags/"); | |
2387 | ||
2388 | /* ALWAYS pack tags */ | |
2389 | if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref) | |
2390 | return 0; | |
2391 | ||
2392 | /* Do not pack symbolic or broken refs: */ | |
2393 | if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry)) | |
2394 | return 0; | |
2395 | ||
2396 | /* Add a packed ref cache entry equivalent to the loose entry. */ | |
2397 | peel_status = peel_entry(entry, 1); | |
2398 | if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG) | |
2399 | die("internal error peeling reference %s (%s)", | |
2400 | entry->name, sha1_to_hex(entry->u.value.sha1)); | |
2401 | packed_entry = find_ref(cb->packed_refs, entry->name); | |
2402 | if (packed_entry) { | |
2403 | /* Overwrite existing packed entry with info from loose entry */ | |
2404 | packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED; | |
2405 | hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1); | |
2406 | } else { | |
2407 | packed_entry = create_ref_entry(entry->name, entry->u.value.sha1, | |
2408 | REF_ISPACKED | REF_KNOWS_PEELED, 0); | |
2409 | add_ref(cb->packed_refs, packed_entry); | |
2410 | } | |
2411 | hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled); | |
2412 | ||
2413 | /* Schedule the loose reference for pruning if requested. */ | |
2414 | if ((cb->flags & PACK_REFS_PRUNE)) { | |
2415 | int namelen = strlen(entry->name) + 1; | |
2416 | struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen); | |
2417 | hashcpy(n->sha1, entry->u.value.sha1); | |
2418 | strcpy(n->name, entry->name); | |
2419 | n->next = cb->ref_to_prune; | |
2420 | cb->ref_to_prune = n; | |
2421 | } | |
2422 | return 0; | |
2423 | } | |
2424 | ||
2425 | /* | |
2426 | * Remove empty parents, but spare refs/ and immediate subdirs. | |
2427 | * Note: munges *name. | |
2428 | */ | |
2429 | static void try_remove_empty_parents(char *name) | |
2430 | { | |
2431 | char *p, *q; | |
2432 | int i; | |
2433 | p = name; | |
2434 | for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */ | |
2435 | while (*p && *p != '/') | |
2436 | p++; | |
2437 | /* tolerate duplicate slashes; see check_refname_format() */ | |
2438 | while (*p == '/') | |
2439 | p++; | |
2440 | } | |
2441 | for (q = p; *q; q++) | |
2442 | ; | |
2443 | while (1) { | |
2444 | while (q > p && *q != '/') | |
2445 | q--; | |
2446 | while (q > p && *(q-1) == '/') | |
2447 | q--; | |
2448 | if (q == p) | |
2449 | break; | |
2450 | *q = '\0'; | |
2451 | if (rmdir(git_path("%s", name))) | |
2452 | break; | |
2453 | } | |
2454 | } | |
2455 | ||
2456 | /* make sure nobody touched the ref, and unlink */ | |
2457 | static void prune_ref(struct ref_to_prune *r) | |
2458 | { | |
2459 | struct ref_transaction *transaction; | |
2460 | struct strbuf err = STRBUF_INIT; | |
2461 | ||
2462 | if (check_refname_format(r->name, 0)) | |
2463 | return; | |
2464 | ||
2465 | transaction = ref_transaction_begin(&err); | |
2466 | if (!transaction || | |
2467 | ref_transaction_delete(transaction, r->name, r->sha1, | |
2468 | REF_ISPRUNING, 1, NULL, &err) || | |
2469 | ref_transaction_commit(transaction, &err)) { | |
2470 | ref_transaction_free(transaction); | |
2471 | error("%s", err.buf); | |
2472 | strbuf_release(&err); | |
2473 | return; | |
2474 | } | |
2475 | ref_transaction_free(transaction); | |
2476 | strbuf_release(&err); | |
2477 | try_remove_empty_parents(r->name); | |
2478 | } | |
2479 | ||
2480 | static void prune_refs(struct ref_to_prune *r) | |
2481 | { | |
2482 | while (r) { | |
2483 | prune_ref(r); | |
2484 | r = r->next; | |
2485 | } | |
2486 | } | |
2487 | ||
2488 | int pack_refs(unsigned int flags) | |
2489 | { | |
2490 | struct pack_refs_cb_data cbdata; | |
2491 | ||
2492 | memset(&cbdata, 0, sizeof(cbdata)); | |
2493 | cbdata.flags = flags; | |
2494 | ||
2495 | lock_packed_refs(LOCK_DIE_ON_ERROR); | |
2496 | cbdata.packed_refs = get_packed_refs(&ref_cache); | |
2497 | ||
2498 | do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0, | |
2499 | pack_if_possible_fn, &cbdata); | |
2500 | ||
2501 | if (commit_packed_refs()) | |
2502 | die_errno("unable to overwrite old ref-pack file"); | |
2503 | ||
2504 | prune_refs(cbdata.ref_to_prune); | |
2505 | return 0; | |
2506 | } | |
2507 | ||
2508 | /* | |
2509 | * If entry is no longer needed in packed-refs, add it to the string | |
2510 | * list pointed to by cb_data. Reasons for deleting entries: | |
2511 | * | |
2512 | * - Entry is broken. | |
2513 | * - Entry is overridden by a loose ref. | |
2514 | * - Entry does not point at a valid object. | |
2515 | * | |
2516 | * In the first and third cases, also emit an error message because these | |
2517 | * are indications of repository corruption. | |
2518 | */ | |
2519 | static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data) | |
2520 | { | |
2521 | struct string_list *refs_to_delete = cb_data; | |
2522 | ||
2523 | if (entry->flag & REF_ISBROKEN) { | |
2524 | /* This shouldn't happen to packed refs. */ | |
2525 | error("%s is broken!", entry->name); | |
2526 | string_list_append(refs_to_delete, entry->name); | |
2527 | return 0; | |
2528 | } | |
2529 | if (!has_sha1_file(entry->u.value.sha1)) { | |
2530 | unsigned char sha1[20]; | |
2531 | int flags; | |
2532 | ||
2533 | if (read_ref_full(entry->name, 0, sha1, &flags)) | |
2534 | /* We should at least have found the packed ref. */ | |
2535 | die("Internal error"); | |
2536 | if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) { | |
2537 | /* | |
2538 | * This packed reference is overridden by a | |
2539 | * loose reference, so it is OK that its value | |
2540 | * is no longer valid; for example, it might | |
2541 | * refer to an object that has been garbage | |
2542 | * collected. For this purpose we don't even | |
2543 | * care whether the loose reference itself is | |
2544 | * invalid, broken, symbolic, etc. Silently | |
2545 | * remove the packed reference. | |
2546 | */ | |
2547 | string_list_append(refs_to_delete, entry->name); | |
2548 | return 0; | |
2549 | } | |
2550 | /* | |
2551 | * There is no overriding loose reference, so the fact | |
2552 | * that this reference doesn't refer to a valid object | |
2553 | * indicates some kind of repository corruption. | |
2554 | * Report the problem, then omit the reference from | |
2555 | * the output. | |
2556 | */ | |
2557 | error("%s does not point to a valid object!", entry->name); | |
2558 | string_list_append(refs_to_delete, entry->name); | |
2559 | return 0; | |
2560 | } | |
2561 | ||
2562 | return 0; | |
2563 | } | |
2564 | ||
2565 | int repack_without_refs(const char **refnames, int n, struct strbuf *err) | |
2566 | { | |
2567 | struct ref_dir *packed; | |
2568 | struct string_list refs_to_delete = STRING_LIST_INIT_DUP; | |
2569 | struct string_list_item *ref_to_delete; | |
2570 | int i, ret, removed = 0; | |
2571 | ||
2572 | /* Look for a packed ref */ | |
2573 | for (i = 0; i < n; i++) | |
2574 | if (get_packed_ref(refnames[i])) | |
2575 | break; | |
2576 | ||
2577 | /* Avoid locking if we have nothing to do */ | |
2578 | if (i == n) | |
2579 | return 0; /* no refname exists in packed refs */ | |
2580 | ||
2581 | if (lock_packed_refs(0)) { | |
2582 | if (err) { | |
2583 | unable_to_lock_message(git_path("packed-refs"), errno, | |
2584 | err); | |
2585 | return -1; | |
2586 | } | |
2587 | unable_to_lock_error(git_path("packed-refs"), errno); | |
2588 | return error("cannot delete '%s' from packed refs", refnames[i]); | |
2589 | } | |
2590 | packed = get_packed_refs(&ref_cache); | |
2591 | ||
2592 | /* Remove refnames from the cache */ | |
2593 | for (i = 0; i < n; i++) | |
2594 | if (remove_entry(packed, refnames[i]) != -1) | |
2595 | removed = 1; | |
2596 | if (!removed) { | |
2597 | /* | |
2598 | * All packed entries disappeared while we were | |
2599 | * acquiring the lock. | |
2600 | */ | |
2601 | rollback_packed_refs(); | |
2602 | return 0; | |
2603 | } | |
2604 | ||
2605 | /* Remove any other accumulated cruft */ | |
2606 | do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete); | |
2607 | for_each_string_list_item(ref_to_delete, &refs_to_delete) { | |
2608 | if (remove_entry(packed, ref_to_delete->string) == -1) | |
2609 | die("internal error"); | |
2610 | } | |
2611 | ||
2612 | /* Write what remains */ | |
2613 | ret = commit_packed_refs(); | |
2614 | if (ret && err) | |
2615 | strbuf_addf(err, "unable to overwrite old ref-pack file: %s", | |
2616 | strerror(errno)); | |
2617 | return ret; | |
2618 | } | |
2619 | ||
2620 | static int delete_ref_loose(struct ref_lock *lock, int flag, struct strbuf *err) | |
2621 | { | |
2622 | if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) { | |
2623 | /* | |
2624 | * loose. The loose file name is the same as the | |
2625 | * lockfile name, minus ".lock": | |
2626 | */ | |
2627 | char *loose_filename = get_locked_file_path(lock->lk); | |
2628 | int res = unlink_or_msg(loose_filename, err); | |
2629 | free(loose_filename); | |
2630 | if (res) | |
2631 | return 1; | |
2632 | } | |
2633 | return 0; | |
2634 | } | |
2635 | ||
2636 | int delete_ref(const char *refname, const unsigned char *sha1, int delopt) | |
2637 | { | |
2638 | struct ref_transaction *transaction; | |
2639 | struct strbuf err = STRBUF_INIT; | |
2640 | ||
2641 | transaction = ref_transaction_begin(&err); | |
2642 | if (!transaction || | |
2643 | ref_transaction_delete(transaction, refname, sha1, delopt, | |
2644 | sha1 && !is_null_sha1(sha1), NULL, &err) || | |
2645 | ref_transaction_commit(transaction, &err)) { | |
2646 | error("%s", err.buf); | |
2647 | ref_transaction_free(transaction); | |
2648 | strbuf_release(&err); | |
2649 | return 1; | |
2650 | } | |
2651 | ref_transaction_free(transaction); | |
2652 | strbuf_release(&err); | |
2653 | return 0; | |
2654 | } | |
2655 | ||
2656 | /* | |
2657 | * People using contrib's git-new-workdir have .git/logs/refs -> | |
2658 | * /some/other/path/.git/logs/refs, and that may live on another device. | |
2659 | * | |
2660 | * IOW, to avoid cross device rename errors, the temporary renamed log must | |
2661 | * live into logs/refs. | |
2662 | */ | |
2663 | #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log" | |
2664 | ||
2665 | static int rename_tmp_log(const char *newrefname) | |
2666 | { | |
2667 | int attempts_remaining = 4; | |
2668 | ||
2669 | retry: | |
2670 | switch (safe_create_leading_directories(git_path("logs/%s", newrefname))) { | |
2671 | case SCLD_OK: | |
2672 | break; /* success */ | |
2673 | case SCLD_VANISHED: | |
2674 | if (--attempts_remaining > 0) | |
2675 | goto retry; | |
2676 | /* fall through */ | |
2677 | default: | |
2678 | error("unable to create directory for %s", newrefname); | |
2679 | return -1; | |
2680 | } | |
2681 | ||
2682 | if (rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) { | |
2683 | if ((errno==EISDIR || errno==ENOTDIR) && --attempts_remaining > 0) { | |
2684 | /* | |
2685 | * rename(a, b) when b is an existing | |
2686 | * directory ought to result in ISDIR, but | |
2687 | * Solaris 5.8 gives ENOTDIR. Sheesh. | |
2688 | */ | |
2689 | if (remove_empty_directories(git_path("logs/%s", newrefname))) { | |
2690 | error("Directory not empty: logs/%s", newrefname); | |
2691 | return -1; | |
2692 | } | |
2693 | goto retry; | |
2694 | } else if (errno == ENOENT && --attempts_remaining > 0) { | |
2695 | /* | |
2696 | * Maybe another process just deleted one of | |
2697 | * the directories in the path to newrefname. | |
2698 | * Try again from the beginning. | |
2699 | */ | |
2700 | goto retry; | |
2701 | } else { | |
2702 | error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s", | |
2703 | newrefname, strerror(errno)); | |
2704 | return -1; | |
2705 | } | |
2706 | } | |
2707 | return 0; | |
2708 | } | |
2709 | ||
2710 | static int rename_ref_available(const char *oldname, const char *newname) | |
2711 | { | |
2712 | struct string_list skip = STRING_LIST_INIT_NODUP; | |
2713 | int ret; | |
2714 | ||
2715 | string_list_insert(&skip, oldname); | |
2716 | ret = is_refname_available(newname, &skip, get_packed_refs(&ref_cache)) | |
2717 | && is_refname_available(newname, &skip, get_loose_refs(&ref_cache)); | |
2718 | string_list_clear(&skip, 0); | |
2719 | return ret; | |
2720 | } | |
2721 | ||
2722 | static int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1, | |
2723 | const char *logmsg); | |
2724 | ||
2725 | int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg) | |
2726 | { | |
2727 | unsigned char sha1[20], orig_sha1[20]; | |
2728 | int flag = 0, logmoved = 0; | |
2729 | struct ref_lock *lock; | |
2730 | struct stat loginfo; | |
2731 | int log = !lstat(git_path("logs/%s", oldrefname), &loginfo); | |
2732 | const char *symref = NULL; | |
2733 | ||
2734 | if (log && S_ISLNK(loginfo.st_mode)) | |
2735 | return error("reflog for %s is a symlink", oldrefname); | |
2736 | ||
2737 | symref = resolve_ref_unsafe(oldrefname, RESOLVE_REF_READING, | |
2738 | orig_sha1, &flag); | |
2739 | if (flag & REF_ISSYMREF) | |
2740 | return error("refname %s is a symbolic ref, renaming it is not supported", | |
2741 | oldrefname); | |
2742 | if (!symref) | |
2743 | return error("refname %s not found", oldrefname); | |
2744 | ||
2745 | if (!rename_ref_available(oldrefname, newrefname)) | |
2746 | return 1; | |
2747 | ||
2748 | if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG))) | |
2749 | return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s", | |
2750 | oldrefname, strerror(errno)); | |
2751 | ||
2752 | if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) { | |
2753 | error("unable to delete old %s", oldrefname); | |
2754 | goto rollback; | |
2755 | } | |
2756 | ||
2757 | if (!read_ref_full(newrefname, RESOLVE_REF_READING, sha1, NULL) && | |
2758 | delete_ref(newrefname, sha1, REF_NODEREF)) { | |
2759 | if (errno==EISDIR) { | |
2760 | if (remove_empty_directories(git_path("%s", newrefname))) { | |
2761 | error("Directory not empty: %s", newrefname); | |
2762 | goto rollback; | |
2763 | } | |
2764 | } else { | |
2765 | error("unable to delete existing %s", newrefname); | |
2766 | goto rollback; | |
2767 | } | |
2768 | } | |
2769 | ||
2770 | if (log && rename_tmp_log(newrefname)) | |
2771 | goto rollback; | |
2772 | ||
2773 | logmoved = log; | |
2774 | ||
2775 | lock = lock_ref_sha1_basic(newrefname, NULL, NULL, 0, NULL); | |
2776 | if (!lock) { | |
2777 | error("unable to lock %s for update", newrefname); | |
2778 | goto rollback; | |
2779 | } | |
2780 | lock->force_write = 1; | |
2781 | hashcpy(lock->old_sha1, orig_sha1); | |
2782 | if (write_ref_sha1(lock, orig_sha1, logmsg)) { | |
2783 | error("unable to write current sha1 into %s", newrefname); | |
2784 | goto rollback; | |
2785 | } | |
2786 | ||
2787 | return 0; | |
2788 | ||
2789 | rollback: | |
2790 | lock = lock_ref_sha1_basic(oldrefname, NULL, NULL, 0, NULL); | |
2791 | if (!lock) { | |
2792 | error("unable to lock %s for rollback", oldrefname); | |
2793 | goto rollbacklog; | |
2794 | } | |
2795 | ||
2796 | lock->force_write = 1; | |
2797 | flag = log_all_ref_updates; | |
2798 | log_all_ref_updates = 0; | |
2799 | if (write_ref_sha1(lock, orig_sha1, NULL)) | |
2800 | error("unable to write current sha1 into %s", oldrefname); | |
2801 | log_all_ref_updates = flag; | |
2802 | ||
2803 | rollbacklog: | |
2804 | if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname))) | |
2805 | error("unable to restore logfile %s from %s: %s", | |
2806 | oldrefname, newrefname, strerror(errno)); | |
2807 | if (!logmoved && log && | |
2808 | rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname))) | |
2809 | error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s", | |
2810 | oldrefname, strerror(errno)); | |
2811 | ||
2812 | return 1; | |
2813 | } | |
2814 | ||
2815 | int close_ref(struct ref_lock *lock) | |
2816 | { | |
2817 | if (close_lock_file(lock->lk)) | |
2818 | return -1; | |
2819 | lock->lock_fd = -1; | |
2820 | return 0; | |
2821 | } | |
2822 | ||
2823 | int commit_ref(struct ref_lock *lock) | |
2824 | { | |
2825 | if (commit_lock_file(lock->lk)) | |
2826 | return -1; | |
2827 | lock->lock_fd = -1; | |
2828 | return 0; | |
2829 | } | |
2830 | ||
2831 | void unlock_ref(struct ref_lock *lock) | |
2832 | { | |
2833 | /* Do not free lock->lk -- atexit() still looks at them */ | |
2834 | if (lock->lk) | |
2835 | rollback_lock_file(lock->lk); | |
2836 | free(lock->ref_name); | |
2837 | free(lock->orig_ref_name); | |
2838 | free(lock); | |
2839 | } | |
2840 | ||
2841 | /* | |
2842 | * copy the reflog message msg to buf, which has been allocated sufficiently | |
2843 | * large, while cleaning up the whitespaces. Especially, convert LF to space, | |
2844 | * because reflog file is one line per entry. | |
2845 | */ | |
2846 | static int copy_msg(char *buf, const char *msg) | |
2847 | { | |
2848 | char *cp = buf; | |
2849 | char c; | |
2850 | int wasspace = 1; | |
2851 | ||
2852 | *cp++ = '\t'; | |
2853 | while ((c = *msg++)) { | |
2854 | if (wasspace && isspace(c)) | |
2855 | continue; | |
2856 | wasspace = isspace(c); | |
2857 | if (wasspace) | |
2858 | c = ' '; | |
2859 | *cp++ = c; | |
2860 | } | |
2861 | while (buf < cp && isspace(cp[-1])) | |
2862 | cp--; | |
2863 | *cp++ = '\n'; | |
2864 | return cp - buf; | |
2865 | } | |
2866 | ||
2867 | /* This function must set a meaningful errno on failure */ | |
2868 | int log_ref_setup(const char *refname, char *logfile, int bufsize) | |
2869 | { | |
2870 | int logfd, oflags = O_APPEND | O_WRONLY; | |
2871 | ||
2872 | git_snpath(logfile, bufsize, "logs/%s", refname); | |
2873 | if (log_all_ref_updates && | |
2874 | (starts_with(refname, "refs/heads/") || | |
2875 | starts_with(refname, "refs/remotes/") || | |
2876 | starts_with(refname, "refs/notes/") || | |
2877 | !strcmp(refname, "HEAD"))) { | |
2878 | if (safe_create_leading_directories(logfile) < 0) { | |
2879 | int save_errno = errno; | |
2880 | error("unable to create directory for %s", logfile); | |
2881 | errno = save_errno; | |
2882 | return -1; | |
2883 | } | |
2884 | oflags |= O_CREAT; | |
2885 | } | |
2886 | ||
2887 | logfd = open(logfile, oflags, 0666); | |
2888 | if (logfd < 0) { | |
2889 | if (!(oflags & O_CREAT) && errno == ENOENT) | |
2890 | return 0; | |
2891 | ||
2892 | if ((oflags & O_CREAT) && errno == EISDIR) { | |
2893 | if (remove_empty_directories(logfile)) { | |
2894 | int save_errno = errno; | |
2895 | error("There are still logs under '%s'", | |
2896 | logfile); | |
2897 | errno = save_errno; | |
2898 | return -1; | |
2899 | } | |
2900 | logfd = open(logfile, oflags, 0666); | |
2901 | } | |
2902 | ||
2903 | if (logfd < 0) { | |
2904 | int save_errno = errno; | |
2905 | error("Unable to append to %s: %s", logfile, | |
2906 | strerror(errno)); | |
2907 | errno = save_errno; | |
2908 | return -1; | |
2909 | } | |
2910 | } | |
2911 | ||
2912 | adjust_shared_perm(logfile); | |
2913 | close(logfd); | |
2914 | return 0; | |
2915 | } | |
2916 | ||
2917 | static int log_ref_write(const char *refname, const unsigned char *old_sha1, | |
2918 | const unsigned char *new_sha1, const char *msg) | |
2919 | { | |
2920 | int logfd, result, written, oflags = O_APPEND | O_WRONLY; | |
2921 | unsigned maxlen, len; | |
2922 | int msglen; | |
2923 | char log_file[PATH_MAX]; | |
2924 | char *logrec; | |
2925 | const char *committer; | |
2926 | ||
2927 | if (log_all_ref_updates < 0) | |
2928 | log_all_ref_updates = !is_bare_repository(); | |
2929 | ||
2930 | result = log_ref_setup(refname, log_file, sizeof(log_file)); | |
2931 | if (result) | |
2932 | return result; | |
2933 | ||
2934 | logfd = open(log_file, oflags); | |
2935 | if (logfd < 0) | |
2936 | return 0; | |
2937 | msglen = msg ? strlen(msg) : 0; | |
2938 | committer = git_committer_info(0); | |
2939 | maxlen = strlen(committer) + msglen + 100; | |
2940 | logrec = xmalloc(maxlen); | |
2941 | len = sprintf(logrec, "%s %s %s\n", | |
2942 | sha1_to_hex(old_sha1), | |
2943 | sha1_to_hex(new_sha1), | |
2944 | committer); | |
2945 | if (msglen) | |
2946 | len += copy_msg(logrec + len - 1, msg) - 1; | |
2947 | written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1; | |
2948 | free(logrec); | |
2949 | if (written != len) { | |
2950 | int save_errno = errno; | |
2951 | close(logfd); | |
2952 | error("Unable to append to %s", log_file); | |
2953 | errno = save_errno; | |
2954 | return -1; | |
2955 | } | |
2956 | if (close(logfd)) { | |
2957 | int save_errno = errno; | |
2958 | error("Unable to append to %s", log_file); | |
2959 | errno = save_errno; | |
2960 | return -1; | |
2961 | } | |
2962 | return 0; | |
2963 | } | |
2964 | ||
2965 | int is_branch(const char *refname) | |
2966 | { | |
2967 | return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/"); | |
2968 | } | |
2969 | ||
2970 | /* | |
2971 | * Write sha1 into the ref specified by the lock. Make sure that errno | |
2972 | * is sane on error. | |
2973 | */ | |
2974 | static int write_ref_sha1(struct ref_lock *lock, | |
2975 | const unsigned char *sha1, const char *logmsg) | |
2976 | { | |
2977 | static char term = '\n'; | |
2978 | struct object *o; | |
2979 | ||
2980 | if (!lock) { | |
2981 | errno = EINVAL; | |
2982 | return -1; | |
2983 | } | |
2984 | if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) { | |
2985 | unlock_ref(lock); | |
2986 | return 0; | |
2987 | } | |
2988 | o = parse_object(sha1); | |
2989 | if (!o) { | |
2990 | error("Trying to write ref %s with nonexistent object %s", | |
2991 | lock->ref_name, sha1_to_hex(sha1)); | |
2992 | unlock_ref(lock); | |
2993 | errno = EINVAL; | |
2994 | return -1; | |
2995 | } | |
2996 | if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) { | |
2997 | error("Trying to write non-commit object %s to branch %s", | |
2998 | sha1_to_hex(sha1), lock->ref_name); | |
2999 | unlock_ref(lock); | |
3000 | errno = EINVAL; | |
3001 | return -1; | |
3002 | } | |
3003 | if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 || | |
3004 | write_in_full(lock->lock_fd, &term, 1) != 1 || | |
3005 | close_ref(lock) < 0) { | |
3006 | int save_errno = errno; | |
3007 | error("Couldn't write %s", lock->lk->filename.buf); | |
3008 | unlock_ref(lock); | |
3009 | errno = save_errno; | |
3010 | return -1; | |
3011 | } | |
3012 | clear_loose_ref_cache(&ref_cache); | |
3013 | if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 || | |
3014 | (strcmp(lock->ref_name, lock->orig_ref_name) && | |
3015 | log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) { | |
3016 | unlock_ref(lock); | |
3017 | return -1; | |
3018 | } | |
3019 | if (strcmp(lock->orig_ref_name, "HEAD") != 0) { | |
3020 | /* | |
3021 | * Special hack: If a branch is updated directly and HEAD | |
3022 | * points to it (may happen on the remote side of a push | |
3023 | * for example) then logically the HEAD reflog should be | |
3024 | * updated too. | |
3025 | * A generic solution implies reverse symref information, | |
3026 | * but finding all symrefs pointing to the given branch | |
3027 | * would be rather costly for this rare event (the direct | |
3028 | * update of a branch) to be worth it. So let's cheat and | |
3029 | * check with HEAD only which should cover 99% of all usage | |
3030 | * scenarios (even 100% of the default ones). | |
3031 | */ | |
3032 | unsigned char head_sha1[20]; | |
3033 | int head_flag; | |
3034 | const char *head_ref; | |
3035 | head_ref = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, | |
3036 | head_sha1, &head_flag); | |
3037 | if (head_ref && (head_flag & REF_ISSYMREF) && | |
3038 | !strcmp(head_ref, lock->ref_name)) | |
3039 | log_ref_write("HEAD", lock->old_sha1, sha1, logmsg); | |
3040 | } | |
3041 | if (commit_ref(lock)) { | |
3042 | error("Couldn't set %s", lock->ref_name); | |
3043 | unlock_ref(lock); | |
3044 | return -1; | |
3045 | } | |
3046 | unlock_ref(lock); | |
3047 | return 0; | |
3048 | } | |
3049 | ||
3050 | int create_symref(const char *ref_target, const char *refs_heads_master, | |
3051 | const char *logmsg) | |
3052 | { | |
3053 | const char *lockpath; | |
3054 | char ref[1000]; | |
3055 | int fd, len, written; | |
3056 | char *git_HEAD = git_pathdup("%s", ref_target); | |
3057 | unsigned char old_sha1[20], new_sha1[20]; | |
3058 | ||
3059 | if (logmsg && read_ref(ref_target, old_sha1)) | |
3060 | hashclr(old_sha1); | |
3061 | ||
3062 | if (safe_create_leading_directories(git_HEAD) < 0) | |
3063 | return error("unable to create directory for %s", git_HEAD); | |
3064 | ||
3065 | #ifndef NO_SYMLINK_HEAD | |
3066 | if (prefer_symlink_refs) { | |
3067 | unlink(git_HEAD); | |
3068 | if (!symlink(refs_heads_master, git_HEAD)) | |
3069 | goto done; | |
3070 | fprintf(stderr, "no symlink - falling back to symbolic ref\n"); | |
3071 | } | |
3072 | #endif | |
3073 | ||
3074 | len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master); | |
3075 | if (sizeof(ref) <= len) { | |
3076 | error("refname too long: %s", refs_heads_master); | |
3077 | goto error_free_return; | |
3078 | } | |
3079 | lockpath = mkpath("%s.lock", git_HEAD); | |
3080 | fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666); | |
3081 | if (fd < 0) { | |
3082 | error("Unable to open %s for writing", lockpath); | |
3083 | goto error_free_return; | |
3084 | } | |
3085 | written = write_in_full(fd, ref, len); | |
3086 | if (close(fd) != 0 || written != len) { | |
3087 | error("Unable to write to %s", lockpath); | |
3088 | goto error_unlink_return; | |
3089 | } | |
3090 | if (rename(lockpath, git_HEAD) < 0) { | |
3091 | error("Unable to create %s", git_HEAD); | |
3092 | goto error_unlink_return; | |
3093 | } | |
3094 | if (adjust_shared_perm(git_HEAD)) { | |
3095 | error("Unable to fix permissions on %s", lockpath); | |
3096 | error_unlink_return: | |
3097 | unlink_or_warn(lockpath); | |
3098 | error_free_return: | |
3099 | free(git_HEAD); | |
3100 | return -1; | |
3101 | } | |
3102 | ||
3103 | #ifndef NO_SYMLINK_HEAD | |
3104 | done: | |
3105 | #endif | |
3106 | if (logmsg && !read_ref(refs_heads_master, new_sha1)) | |
3107 | log_ref_write(ref_target, old_sha1, new_sha1, logmsg); | |
3108 | ||
3109 | free(git_HEAD); | |
3110 | return 0; | |
3111 | } | |
3112 | ||
3113 | struct read_ref_at_cb { | |
3114 | const char *refname; | |
3115 | unsigned long at_time; | |
3116 | int cnt; | |
3117 | int reccnt; | |
3118 | unsigned char *sha1; | |
3119 | int found_it; | |
3120 | ||
3121 | unsigned char osha1[20]; | |
3122 | unsigned char nsha1[20]; | |
3123 | int tz; | |
3124 | unsigned long date; | |
3125 | char **msg; | |
3126 | unsigned long *cutoff_time; | |
3127 | int *cutoff_tz; | |
3128 | int *cutoff_cnt; | |
3129 | }; | |
3130 | ||
3131 | static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1, | |
3132 | const char *email, unsigned long timestamp, int tz, | |
3133 | const char *message, void *cb_data) | |
3134 | { | |
3135 | struct read_ref_at_cb *cb = cb_data; | |
3136 | ||
3137 | cb->reccnt++; | |
3138 | cb->tz = tz; | |
3139 | cb->date = timestamp; | |
3140 | ||
3141 | if (timestamp <= cb->at_time || cb->cnt == 0) { | |
3142 | if (cb->msg) | |
3143 | *cb->msg = xstrdup(message); | |
3144 | if (cb->cutoff_time) | |
3145 | *cb->cutoff_time = timestamp; | |
3146 | if (cb->cutoff_tz) | |
3147 | *cb->cutoff_tz = tz; | |
3148 | if (cb->cutoff_cnt) | |
3149 | *cb->cutoff_cnt = cb->reccnt - 1; | |
3150 | /* | |
3151 | * we have not yet updated cb->[n|o]sha1 so they still | |
3152 | * hold the values for the previous record. | |
3153 | */ | |
3154 | if (!is_null_sha1(cb->osha1)) { | |
3155 | hashcpy(cb->sha1, nsha1); | |
3156 | if (hashcmp(cb->osha1, nsha1)) | |
3157 | warning("Log for ref %s has gap after %s.", | |
3158 | cb->refname, show_date(cb->date, cb->tz, DATE_RFC2822)); | |
3159 | } | |
3160 | else if (cb->date == cb->at_time) | |
3161 | hashcpy(cb->sha1, nsha1); | |
3162 | else if (hashcmp(nsha1, cb->sha1)) | |
3163 | warning("Log for ref %s unexpectedly ended on %s.", | |
3164 | cb->refname, show_date(cb->date, cb->tz, | |
3165 | DATE_RFC2822)); | |
3166 | hashcpy(cb->osha1, osha1); | |
3167 | hashcpy(cb->nsha1, nsha1); | |
3168 | cb->found_it = 1; | |
3169 | return 1; | |
3170 | } | |
3171 | hashcpy(cb->osha1, osha1); | |
3172 | hashcpy(cb->nsha1, nsha1); | |
3173 | if (cb->cnt > 0) | |
3174 | cb->cnt--; | |
3175 | return 0; | |
3176 | } | |
3177 | ||
3178 | static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1, | |
3179 | const char *email, unsigned long timestamp, | |
3180 | int tz, const char *message, void *cb_data) | |
3181 | { | |
3182 | struct read_ref_at_cb *cb = cb_data; | |
3183 | ||
3184 | if (cb->msg) | |
3185 | *cb->msg = xstrdup(message); | |
3186 | if (cb->cutoff_time) | |
3187 | *cb->cutoff_time = timestamp; | |
3188 | if (cb->cutoff_tz) | |
3189 | *cb->cutoff_tz = tz; | |
3190 | if (cb->cutoff_cnt) | |
3191 | *cb->cutoff_cnt = cb->reccnt; | |
3192 | hashcpy(cb->sha1, osha1); | |
3193 | if (is_null_sha1(cb->sha1)) | |
3194 | hashcpy(cb->sha1, nsha1); | |
3195 | /* We just want the first entry */ | |
3196 | return 1; | |
3197 | } | |
3198 | ||
3199 | int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt, | |
3200 | unsigned char *sha1, char **msg, | |
3201 | unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt) | |
3202 | { | |
3203 | struct read_ref_at_cb cb; | |
3204 | ||
3205 | memset(&cb, 0, sizeof(cb)); | |
3206 | cb.refname = refname; | |
3207 | cb.at_time = at_time; | |
3208 | cb.cnt = cnt; | |
3209 | cb.msg = msg; | |
3210 | cb.cutoff_time = cutoff_time; | |
3211 | cb.cutoff_tz = cutoff_tz; | |
3212 | cb.cutoff_cnt = cutoff_cnt; | |
3213 | cb.sha1 = sha1; | |
3214 | ||
3215 | for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb); | |
3216 | ||
3217 | if (!cb.reccnt) { | |
3218 | if (flags & GET_SHA1_QUIETLY) | |
3219 | exit(128); | |
3220 | else | |
3221 | die("Log for %s is empty.", refname); | |
3222 | } | |
3223 | if (cb.found_it) | |
3224 | return 0; | |
3225 | ||
3226 | for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb); | |
3227 | ||
3228 | return 1; | |
3229 | } | |
3230 | ||
3231 | int reflog_exists(const char *refname) | |
3232 | { | |
3233 | struct stat st; | |
3234 | ||
3235 | return !lstat(git_path("logs/%s", refname), &st) && | |
3236 | S_ISREG(st.st_mode); | |
3237 | } | |
3238 | ||
3239 | int delete_reflog(const char *refname) | |
3240 | { | |
3241 | return remove_path(git_path("logs/%s", refname)); | |
3242 | } | |
3243 | ||
3244 | static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data) | |
3245 | { | |
3246 | unsigned char osha1[20], nsha1[20]; | |
3247 | char *email_end, *message; | |
3248 | unsigned long timestamp; | |
3249 | int tz; | |
3250 | ||
3251 | /* old SP new SP name <email> SP time TAB msg LF */ | |
3252 | if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' || | |
3253 | get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' || | |
3254 | get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' || | |
3255 | !(email_end = strchr(sb->buf + 82, '>')) || | |
3256 | email_end[1] != ' ' || | |
3257 | !(timestamp = strtoul(email_end + 2, &message, 10)) || | |
3258 | !message || message[0] != ' ' || | |
3259 | (message[1] != '+' && message[1] != '-') || | |
3260 | !isdigit(message[2]) || !isdigit(message[3]) || | |
3261 | !isdigit(message[4]) || !isdigit(message[5])) | |
3262 | return 0; /* corrupt? */ | |
3263 | email_end[1] = '\0'; | |
3264 | tz = strtol(message + 1, NULL, 10); | |
3265 | if (message[6] != '\t') | |
3266 | message += 6; | |
3267 | else | |
3268 | message += 7; | |
3269 | return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data); | |
3270 | } | |
3271 | ||
3272 | static char *find_beginning_of_line(char *bob, char *scan) | |
3273 | { | |
3274 | while (bob < scan && *(--scan) != '\n') | |
3275 | ; /* keep scanning backwards */ | |
3276 | /* | |
3277 | * Return either beginning of the buffer, or LF at the end of | |
3278 | * the previous line. | |
3279 | */ | |
3280 | return scan; | |
3281 | } | |
3282 | ||
3283 | int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data) | |
3284 | { | |
3285 | struct strbuf sb = STRBUF_INIT; | |
3286 | FILE *logfp; | |
3287 | long pos; | |
3288 | int ret = 0, at_tail = 1; | |
3289 | ||
3290 | logfp = fopen(git_path("logs/%s", refname), "r"); | |
3291 | if (!logfp) | |
3292 | return -1; | |
3293 | ||
3294 | /* Jump to the end */ | |
3295 | if (fseek(logfp, 0, SEEK_END) < 0) | |
3296 | return error("cannot seek back reflog for %s: %s", | |
3297 | refname, strerror(errno)); | |
3298 | pos = ftell(logfp); | |
3299 | while (!ret && 0 < pos) { | |
3300 | int cnt; | |
3301 | size_t nread; | |
3302 | char buf[BUFSIZ]; | |
3303 | char *endp, *scanp; | |
3304 | ||
3305 | /* Fill next block from the end */ | |
3306 | cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos; | |
3307 | if (fseek(logfp, pos - cnt, SEEK_SET)) | |
3308 | return error("cannot seek back reflog for %s: %s", | |
3309 | refname, strerror(errno)); | |
3310 | nread = fread(buf, cnt, 1, logfp); | |
3311 | if (nread != 1) | |
3312 | return error("cannot read %d bytes from reflog for %s: %s", | |
3313 | cnt, refname, strerror(errno)); | |
3314 | pos -= cnt; | |
3315 | ||
3316 | scanp = endp = buf + cnt; | |
3317 | if (at_tail && scanp[-1] == '\n') | |
3318 | /* Looking at the final LF at the end of the file */ | |
3319 | scanp--; | |
3320 | at_tail = 0; | |
3321 | ||
3322 | while (buf < scanp) { | |
3323 | /* | |
3324 | * terminating LF of the previous line, or the beginning | |
3325 | * of the buffer. | |
3326 | */ | |
3327 | char *bp; | |
3328 | ||
3329 | bp = find_beginning_of_line(buf, scanp); | |
3330 | ||
3331 | if (*bp != '\n') { | |
3332 | strbuf_splice(&sb, 0, 0, buf, endp - buf); | |
3333 | if (pos) | |
3334 | break; /* need to fill another block */ | |
3335 | scanp = buf - 1; /* leave loop */ | |
3336 | } else { | |
3337 | /* | |
3338 | * (bp + 1) thru endp is the beginning of the | |
3339 | * current line we have in sb | |
3340 | */ | |
3341 | strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1)); | |
3342 | scanp = bp; | |
3343 | endp = bp + 1; | |
3344 | } | |
3345 | ret = show_one_reflog_ent(&sb, fn, cb_data); | |
3346 | strbuf_reset(&sb); | |
3347 | if (ret) | |
3348 | break; | |
3349 | } | |
3350 | ||
3351 | } | |
3352 | if (!ret && sb.len) | |
3353 | ret = show_one_reflog_ent(&sb, fn, cb_data); | |
3354 | ||
3355 | fclose(logfp); | |
3356 | strbuf_release(&sb); | |
3357 | return ret; | |
3358 | } | |
3359 | ||
3360 | int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data) | |
3361 | { | |
3362 | FILE *logfp; | |
3363 | struct strbuf sb = STRBUF_INIT; | |
3364 | int ret = 0; | |
3365 | ||
3366 | logfp = fopen(git_path("logs/%s", refname), "r"); | |
3367 | if (!logfp) | |
3368 | return -1; | |
3369 | ||
3370 | while (!ret && !strbuf_getwholeline(&sb, logfp, '\n')) | |
3371 | ret = show_one_reflog_ent(&sb, fn, cb_data); | |
3372 | fclose(logfp); | |
3373 | strbuf_release(&sb); | |
3374 | return ret; | |
3375 | } | |
3376 | /* | |
3377 | * Call fn for each reflog in the namespace indicated by name. name | |
3378 | * must be empty or end with '/'. Name will be used as a scratch | |
3379 | * space, but its contents will be restored before return. | |
3380 | */ | |
3381 | static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data) | |
3382 | { | |
3383 | DIR *d = opendir(git_path("logs/%s", name->buf)); | |
3384 | int retval = 0; | |
3385 | struct dirent *de; | |
3386 | int oldlen = name->len; | |
3387 | ||
3388 | if (!d) | |
3389 | return name->len ? errno : 0; | |
3390 | ||
3391 | while ((de = readdir(d)) != NULL) { | |
3392 | struct stat st; | |
3393 | ||
3394 | if (de->d_name[0] == '.') | |
3395 | continue; | |
3396 | if (ends_with(de->d_name, ".lock")) | |
3397 | continue; | |
3398 | strbuf_addstr(name, de->d_name); | |
3399 | if (stat(git_path("logs/%s", name->buf), &st) < 0) { | |
3400 | ; /* silently ignore */ | |
3401 | } else { | |
3402 | if (S_ISDIR(st.st_mode)) { | |
3403 | strbuf_addch(name, '/'); | |
3404 | retval = do_for_each_reflog(name, fn, cb_data); | |
3405 | } else { | |
3406 | unsigned char sha1[20]; | |
3407 | if (read_ref_full(name->buf, 0, sha1, NULL)) | |
3408 | retval = error("bad ref for %s", name->buf); | |
3409 | else | |
3410 | retval = fn(name->buf, sha1, 0, cb_data); | |
3411 | } | |
3412 | if (retval) | |
3413 | break; | |
3414 | } | |
3415 | strbuf_setlen(name, oldlen); | |
3416 | } | |
3417 | closedir(d); | |
3418 | return retval; | |
3419 | } | |
3420 | ||
3421 | int for_each_reflog(each_ref_fn fn, void *cb_data) | |
3422 | { | |
3423 | int retval; | |
3424 | struct strbuf name; | |
3425 | strbuf_init(&name, PATH_MAX); | |
3426 | retval = do_for_each_reflog(&name, fn, cb_data); | |
3427 | strbuf_release(&name); | |
3428 | return retval; | |
3429 | } | |
3430 | ||
3431 | /** | |
3432 | * Information needed for a single ref update. Set new_sha1 to the | |
3433 | * new value or to zero to delete the ref. To check the old value | |
3434 | * while locking the ref, set have_old to 1 and set old_sha1 to the | |
3435 | * value or to zero to ensure the ref does not exist before update. | |
3436 | */ | |
3437 | struct ref_update { | |
3438 | unsigned char new_sha1[20]; | |
3439 | unsigned char old_sha1[20]; | |
3440 | int flags; /* REF_NODEREF? */ | |
3441 | int have_old; /* 1 if old_sha1 is valid, 0 otherwise */ | |
3442 | struct ref_lock *lock; | |
3443 | int type; | |
3444 | char *msg; | |
3445 | const char refname[FLEX_ARRAY]; | |
3446 | }; | |
3447 | ||
3448 | /* | |
3449 | * Transaction states. | |
3450 | * OPEN: The transaction is in a valid state and can accept new updates. | |
3451 | * An OPEN transaction can be committed. | |
3452 | * CLOSED: A closed transaction is no longer active and no other operations | |
3453 | * than free can be used on it in this state. | |
3454 | * A transaction can either become closed by successfully committing | |
3455 | * an active transaction or if there is a failure while building | |
3456 | * the transaction thus rendering it failed/inactive. | |
3457 | */ | |
3458 | enum ref_transaction_state { | |
3459 | REF_TRANSACTION_OPEN = 0, | |
3460 | REF_TRANSACTION_CLOSED = 1 | |
3461 | }; | |
3462 | ||
3463 | /* | |
3464 | * Data structure for holding a reference transaction, which can | |
3465 | * consist of checks and updates to multiple references, carried out | |
3466 | * as atomically as possible. This structure is opaque to callers. | |
3467 | */ | |
3468 | struct ref_transaction { | |
3469 | struct ref_update **updates; | |
3470 | size_t alloc; | |
3471 | size_t nr; | |
3472 | enum ref_transaction_state state; | |
3473 | }; | |
3474 | ||
3475 | struct ref_transaction *ref_transaction_begin(struct strbuf *err) | |
3476 | { | |
3477 | return xcalloc(1, sizeof(struct ref_transaction)); | |
3478 | } | |
3479 | ||
3480 | void ref_transaction_free(struct ref_transaction *transaction) | |
3481 | { | |
3482 | int i; | |
3483 | ||
3484 | if (!transaction) | |
3485 | return; | |
3486 | ||
3487 | for (i = 0; i < transaction->nr; i++) { | |
3488 | free(transaction->updates[i]->msg); | |
3489 | free(transaction->updates[i]); | |
3490 | } | |
3491 | free(transaction->updates); | |
3492 | free(transaction); | |
3493 | } | |
3494 | ||
3495 | static struct ref_update *add_update(struct ref_transaction *transaction, | |
3496 | const char *refname) | |
3497 | { | |
3498 | size_t len = strlen(refname); | |
3499 | struct ref_update *update = xcalloc(1, sizeof(*update) + len + 1); | |
3500 | ||
3501 | strcpy((char *)update->refname, refname); | |
3502 | ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc); | |
3503 | transaction->updates[transaction->nr++] = update; | |
3504 | return update; | |
3505 | } | |
3506 | ||
3507 | int ref_transaction_update(struct ref_transaction *transaction, | |
3508 | const char *refname, | |
3509 | const unsigned char *new_sha1, | |
3510 | const unsigned char *old_sha1, | |
3511 | int flags, int have_old, const char *msg, | |
3512 | struct strbuf *err) | |
3513 | { | |
3514 | struct ref_update *update; | |
3515 | ||
3516 | if (transaction->state != REF_TRANSACTION_OPEN) | |
3517 | die("BUG: update called for transaction that is not open"); | |
3518 | ||
3519 | if (have_old && !old_sha1) | |
3520 | die("BUG: have_old is true but old_sha1 is NULL"); | |
3521 | ||
3522 | update = add_update(transaction, refname); | |
3523 | hashcpy(update->new_sha1, new_sha1); | |
3524 | update->flags = flags; | |
3525 | update->have_old = have_old; | |
3526 | if (have_old) | |
3527 | hashcpy(update->old_sha1, old_sha1); | |
3528 | if (msg) | |
3529 | update->msg = xstrdup(msg); | |
3530 | return 0; | |
3531 | } | |
3532 | ||
3533 | int ref_transaction_create(struct ref_transaction *transaction, | |
3534 | const char *refname, | |
3535 | const unsigned char *new_sha1, | |
3536 | int flags, const char *msg, | |
3537 | struct strbuf *err) | |
3538 | { | |
3539 | struct ref_update *update; | |
3540 | ||
3541 | if (transaction->state != REF_TRANSACTION_OPEN) | |
3542 | die("BUG: create called for transaction that is not open"); | |
3543 | ||
3544 | if (!new_sha1 || is_null_sha1(new_sha1)) | |
3545 | die("BUG: create ref with null new_sha1"); | |
3546 | ||
3547 | update = add_update(transaction, refname); | |
3548 | ||
3549 | hashcpy(update->new_sha1, new_sha1); | |
3550 | hashclr(update->old_sha1); | |
3551 | update->flags = flags; | |
3552 | update->have_old = 1; | |
3553 | if (msg) | |
3554 | update->msg = xstrdup(msg); | |
3555 | return 0; | |
3556 | } | |
3557 | ||
3558 | int ref_transaction_delete(struct ref_transaction *transaction, | |
3559 | const char *refname, | |
3560 | const unsigned char *old_sha1, | |
3561 | int flags, int have_old, const char *msg, | |
3562 | struct strbuf *err) | |
3563 | { | |
3564 | struct ref_update *update; | |
3565 | ||
3566 | if (transaction->state != REF_TRANSACTION_OPEN) | |
3567 | die("BUG: delete called for transaction that is not open"); | |
3568 | ||
3569 | if (have_old && !old_sha1) | |
3570 | die("BUG: have_old is true but old_sha1 is NULL"); | |
3571 | ||
3572 | update = add_update(transaction, refname); | |
3573 | update->flags = flags; | |
3574 | update->have_old = have_old; | |
3575 | if (have_old) { | |
3576 | assert(!is_null_sha1(old_sha1)); | |
3577 | hashcpy(update->old_sha1, old_sha1); | |
3578 | } | |
3579 | if (msg) | |
3580 | update->msg = xstrdup(msg); | |
3581 | return 0; | |
3582 | } | |
3583 | ||
3584 | int update_ref(const char *action, const char *refname, | |
3585 | const unsigned char *sha1, const unsigned char *oldval, | |
3586 | int flags, enum action_on_err onerr) | |
3587 | { | |
3588 | struct ref_transaction *t; | |
3589 | struct strbuf err = STRBUF_INIT; | |
3590 | ||
3591 | t = ref_transaction_begin(&err); | |
3592 | if (!t || | |
3593 | ref_transaction_update(t, refname, sha1, oldval, flags, | |
3594 | !!oldval, action, &err) || | |
3595 | ref_transaction_commit(t, &err)) { | |
3596 | const char *str = "update_ref failed for ref '%s': %s"; | |
3597 | ||
3598 | ref_transaction_free(t); | |
3599 | switch (onerr) { | |
3600 | case UPDATE_REFS_MSG_ON_ERR: | |
3601 | error(str, refname, err.buf); | |
3602 | break; | |
3603 | case UPDATE_REFS_DIE_ON_ERR: | |
3604 | die(str, refname, err.buf); | |
3605 | break; | |
3606 | case UPDATE_REFS_QUIET_ON_ERR: | |
3607 | break; | |
3608 | } | |
3609 | strbuf_release(&err); | |
3610 | return 1; | |
3611 | } | |
3612 | strbuf_release(&err); | |
3613 | ref_transaction_free(t); | |
3614 | return 0; | |
3615 | } | |
3616 | ||
3617 | static int ref_update_compare(const void *r1, const void *r2) | |
3618 | { | |
3619 | const struct ref_update * const *u1 = r1; | |
3620 | const struct ref_update * const *u2 = r2; | |
3621 | return strcmp((*u1)->refname, (*u2)->refname); | |
3622 | } | |
3623 | ||
3624 | static int ref_update_reject_duplicates(struct ref_update **updates, int n, | |
3625 | struct strbuf *err) | |
3626 | { | |
3627 | int i; | |
3628 | for (i = 1; i < n; i++) | |
3629 | if (!strcmp(updates[i - 1]->refname, updates[i]->refname)) { | |
3630 | const char *str = | |
3631 | "Multiple updates for ref '%s' not allowed."; | |
3632 | if (err) | |
3633 | strbuf_addf(err, str, updates[i]->refname); | |
3634 | ||
3635 | return 1; | |
3636 | } | |
3637 | return 0; | |
3638 | } | |
3639 | ||
3640 | int ref_transaction_commit(struct ref_transaction *transaction, | |
3641 | struct strbuf *err) | |
3642 | { | |
3643 | int ret = 0, delnum = 0, i; | |
3644 | const char **delnames; | |
3645 | int n = transaction->nr; | |
3646 | struct ref_update **updates = transaction->updates; | |
3647 | ||
3648 | if (transaction->state != REF_TRANSACTION_OPEN) | |
3649 | die("BUG: commit called for transaction that is not open"); | |
3650 | ||
3651 | if (!n) { | |
3652 | transaction->state = REF_TRANSACTION_CLOSED; | |
3653 | return 0; | |
3654 | } | |
3655 | ||
3656 | /* Allocate work space */ | |
3657 | delnames = xmalloc(sizeof(*delnames) * n); | |
3658 | ||
3659 | /* Copy, sort, and reject duplicate refs */ | |
3660 | qsort(updates, n, sizeof(*updates), ref_update_compare); | |
3661 | if (ref_update_reject_duplicates(updates, n, err)) { | |
3662 | ret = TRANSACTION_GENERIC_ERROR; | |
3663 | goto cleanup; | |
3664 | } | |
3665 | ||
3666 | /* Acquire all locks while verifying old values */ | |
3667 | for (i = 0; i < n; i++) { | |
3668 | struct ref_update *update = updates[i]; | |
3669 | int flags = update->flags; | |
3670 | ||
3671 | if (is_null_sha1(update->new_sha1)) | |
3672 | flags |= REF_DELETING; | |
3673 | update->lock = lock_ref_sha1_basic(update->refname, | |
3674 | (update->have_old ? | |
3675 | update->old_sha1 : | |
3676 | NULL), | |
3677 | NULL, | |
3678 | flags, | |
3679 | &update->type); | |
3680 | if (!update->lock) { | |
3681 | ret = (errno == ENOTDIR) | |
3682 | ? TRANSACTION_NAME_CONFLICT | |
3683 | : TRANSACTION_GENERIC_ERROR; | |
3684 | if (err) | |
3685 | strbuf_addf(err, "Cannot lock the ref '%s'.", | |
3686 | update->refname); | |
3687 | goto cleanup; | |
3688 | } | |
3689 | } | |
3690 | ||
3691 | /* Perform updates first so live commits remain referenced */ | |
3692 | for (i = 0; i < n; i++) { | |
3693 | struct ref_update *update = updates[i]; | |
3694 | ||
3695 | if (!is_null_sha1(update->new_sha1)) { | |
3696 | if (write_ref_sha1(update->lock, update->new_sha1, | |
3697 | update->msg)) { | |
3698 | update->lock = NULL; /* freed by write_ref_sha1 */ | |
3699 | if (err) | |
3700 | strbuf_addf(err, "Cannot update the ref '%s'.", | |
3701 | update->refname); | |
3702 | ret = TRANSACTION_GENERIC_ERROR; | |
3703 | goto cleanup; | |
3704 | } | |
3705 | update->lock = NULL; /* freed by write_ref_sha1 */ | |
3706 | } | |
3707 | } | |
3708 | ||
3709 | /* Perform deletes now that updates are safely completed */ | |
3710 | for (i = 0; i < n; i++) { | |
3711 | struct ref_update *update = updates[i]; | |
3712 | ||
3713 | if (update->lock) { | |
3714 | if (delete_ref_loose(update->lock, update->type, err)) | |
3715 | ret = TRANSACTION_GENERIC_ERROR; | |
3716 | ||
3717 | if (!(update->flags & REF_ISPRUNING)) | |
3718 | delnames[delnum++] = update->lock->ref_name; | |
3719 | } | |
3720 | } | |
3721 | ||
3722 | if (repack_without_refs(delnames, delnum, err)) | |
3723 | ret = TRANSACTION_GENERIC_ERROR; | |
3724 | for (i = 0; i < delnum; i++) | |
3725 | unlink_or_warn(git_path("logs/%s", delnames[i])); | |
3726 | clear_loose_ref_cache(&ref_cache); | |
3727 | ||
3728 | cleanup: | |
3729 | transaction->state = REF_TRANSACTION_CLOSED; | |
3730 | ||
3731 | for (i = 0; i < n; i++) | |
3732 | if (updates[i]->lock) | |
3733 | unlock_ref(updates[i]->lock); | |
3734 | free(delnames); | |
3735 | return ret; | |
3736 | } | |
3737 | ||
3738 | char *shorten_unambiguous_ref(const char *refname, int strict) | |
3739 | { | |
3740 | int i; | |
3741 | static char **scanf_fmts; | |
3742 | static int nr_rules; | |
3743 | char *short_name; | |
3744 | ||
3745 | if (!nr_rules) { | |
3746 | /* | |
3747 | * Pre-generate scanf formats from ref_rev_parse_rules[]. | |
3748 | * Generate a format suitable for scanf from a | |
3749 | * ref_rev_parse_rules rule by interpolating "%s" at the | |
3750 | * location of the "%.*s". | |
3751 | */ | |
3752 | size_t total_len = 0; | |
3753 | size_t offset = 0; | |
3754 | ||
3755 | /* the rule list is NULL terminated, count them first */ | |
3756 | for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++) | |
3757 | /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */ | |
3758 | total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1; | |
3759 | ||
3760 | scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len); | |
3761 | ||
3762 | offset = 0; | |
3763 | for (i = 0; i < nr_rules; i++) { | |
3764 | assert(offset < total_len); | |
3765 | scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset; | |
3766 | offset += snprintf(scanf_fmts[i], total_len - offset, | |
3767 | ref_rev_parse_rules[i], 2, "%s") + 1; | |
3768 | } | |
3769 | } | |
3770 | ||
3771 | /* bail out if there are no rules */ | |
3772 | if (!nr_rules) | |
3773 | return xstrdup(refname); | |
3774 | ||
3775 | /* buffer for scanf result, at most refname must fit */ | |
3776 | short_name = xstrdup(refname); | |
3777 | ||
3778 | /* skip first rule, it will always match */ | |
3779 | for (i = nr_rules - 1; i > 0 ; --i) { | |
3780 | int j; | |
3781 | int rules_to_fail = i; | |
3782 | int short_name_len; | |
3783 | ||
3784 | if (1 != sscanf(refname, scanf_fmts[i], short_name)) | |
3785 | continue; | |
3786 | ||
3787 | short_name_len = strlen(short_name); | |
3788 | ||
3789 | /* | |
3790 | * in strict mode, all (except the matched one) rules | |
3791 | * must fail to resolve to a valid non-ambiguous ref | |
3792 | */ | |
3793 | if (strict) | |
3794 | rules_to_fail = nr_rules; | |
3795 | ||
3796 | /* | |
3797 | * check if the short name resolves to a valid ref, | |
3798 | * but use only rules prior to the matched one | |
3799 | */ | |
3800 | for (j = 0; j < rules_to_fail; j++) { | |
3801 | const char *rule = ref_rev_parse_rules[j]; | |
3802 | char refname[PATH_MAX]; | |
3803 | ||
3804 | /* skip matched rule */ | |
3805 | if (i == j) | |
3806 | continue; | |
3807 | ||
3808 | /* | |
3809 | * the short name is ambiguous, if it resolves | |
3810 | * (with this previous rule) to a valid ref | |
3811 | * read_ref() returns 0 on success | |
3812 | */ | |
3813 | mksnpath(refname, sizeof(refname), | |
3814 | rule, short_name_len, short_name); | |
3815 | if (ref_exists(refname)) | |
3816 | break; | |
3817 | } | |
3818 | ||
3819 | /* | |
3820 | * short name is non-ambiguous if all previous rules | |
3821 | * haven't resolved to a valid ref | |
3822 | */ | |
3823 | if (j == rules_to_fail) | |
3824 | return short_name; | |
3825 | } | |
3826 | ||
3827 | free(short_name); | |
3828 | return xstrdup(refname); | |
3829 | } | |
3830 | ||
3831 | static struct string_list *hide_refs; | |
3832 | ||
3833 | int parse_hide_refs_config(const char *var, const char *value, const char *section) | |
3834 | { | |
3835 | if (!strcmp("transfer.hiderefs", var) || | |
3836 | /* NEEDSWORK: use parse_config_key() once both are merged */ | |
3837 | (starts_with(var, section) && var[strlen(section)] == '.' && | |
3838 | !strcmp(var + strlen(section), ".hiderefs"))) { | |
3839 | char *ref; | |
3840 | int len; | |
3841 | ||
3842 | if (!value) | |
3843 | return config_error_nonbool(var); | |
3844 | ref = xstrdup(value); | |
3845 | len = strlen(ref); | |
3846 | while (len && ref[len - 1] == '/') | |
3847 | ref[--len] = '\0'; | |
3848 | if (!hide_refs) { | |
3849 | hide_refs = xcalloc(1, sizeof(*hide_refs)); | |
3850 | hide_refs->strdup_strings = 1; | |
3851 | } | |
3852 | string_list_append(hide_refs, ref); | |
3853 | } | |
3854 | return 0; | |
3855 | } | |
3856 | ||
3857 | int ref_is_hidden(const char *refname) | |
3858 | { | |
3859 | struct string_list_item *item; | |
3860 | ||
3861 | if (!hide_refs) | |
3862 | return 0; | |
3863 | for_each_string_list_item(item, hide_refs) { | |
3864 | int len; | |
3865 | if (!starts_with(refname, item->string)) | |
3866 | continue; | |
3867 | len = strlen(item->string); | |
3868 | if (!refname[len] || refname[len] == '/') | |
3869 | return 1; | |
3870 | } | |
3871 | return 0; | |
3872 | } |