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1 | #include "../cache.h" | |
2 | #include "../refs.h" | |
3 | #include "refs-internal.h" | |
4 | #include "../iterator.h" | |
5 | #include "../dir-iterator.h" | |
6 | #include "../lockfile.h" | |
7 | #include "../object.h" | |
8 | #include "../dir.h" | |
9 | ||
10 | struct ref_lock { | |
11 | char *ref_name; | |
12 | struct lock_file *lk; | |
13 | struct object_id old_oid; | |
14 | }; | |
15 | ||
16 | struct ref_entry; | |
17 | ||
18 | /* | |
19 | * Information used (along with the information in ref_entry) to | |
20 | * describe a single cached reference. This data structure only | |
21 | * occurs embedded in a union in struct ref_entry, and only when | |
22 | * (ref_entry->flag & REF_DIR) is zero. | |
23 | */ | |
24 | struct ref_value { | |
25 | /* | |
26 | * The name of the object to which this reference resolves | |
27 | * (which may be a tag object). If REF_ISBROKEN, this is | |
28 | * null. If REF_ISSYMREF, then this is the name of the object | |
29 | * referred to by the last reference in the symlink chain. | |
30 | */ | |
31 | struct object_id oid; | |
32 | ||
33 | /* | |
34 | * If REF_KNOWS_PEELED, then this field holds the peeled value | |
35 | * of this reference, or null if the reference is known not to | |
36 | * be peelable. See the documentation for peel_ref() for an | |
37 | * exact definition of "peelable". | |
38 | */ | |
39 | struct object_id peeled; | |
40 | }; | |
41 | ||
42 | struct files_ref_store; | |
43 | ||
44 | /* | |
45 | * Information used (along with the information in ref_entry) to | |
46 | * describe a level in the hierarchy of references. This data | |
47 | * structure only occurs embedded in a union in struct ref_entry, and | |
48 | * only when (ref_entry.flag & REF_DIR) is set. In that case, | |
49 | * (ref_entry.flag & REF_INCOMPLETE) determines whether the references | |
50 | * in the directory have already been read: | |
51 | * | |
52 | * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose | |
53 | * or packed references, already read. | |
54 | * | |
55 | * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose | |
56 | * references that hasn't been read yet (nor has any of its | |
57 | * subdirectories). | |
58 | * | |
59 | * Entries within a directory are stored within a growable array of | |
60 | * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < | |
61 | * sorted are sorted by their component name in strcmp() order and the | |
62 | * remaining entries are unsorted. | |
63 | * | |
64 | * Loose references are read lazily, one directory at a time. When a | |
65 | * directory of loose references is read, then all of the references | |
66 | * in that directory are stored, and REF_INCOMPLETE stubs are created | |
67 | * for any subdirectories, but the subdirectories themselves are not | |
68 | * read. The reading is triggered by get_ref_dir(). | |
69 | */ | |
70 | struct ref_dir { | |
71 | int nr, alloc; | |
72 | ||
73 | /* | |
74 | * Entries with index 0 <= i < sorted are sorted by name. New | |
75 | * entries are appended to the list unsorted, and are sorted | |
76 | * only when required; thus we avoid the need to sort the list | |
77 | * after the addition of every reference. | |
78 | */ | |
79 | int sorted; | |
80 | ||
81 | /* A pointer to the files_ref_store that contains this ref_dir. */ | |
82 | struct files_ref_store *ref_store; | |
83 | ||
84 | struct ref_entry **entries; | |
85 | }; | |
86 | ||
87 | /* | |
88 | * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, | |
89 | * REF_ISPACKED=0x02, REF_ISBROKEN=0x04 and REF_BAD_NAME=0x08 are | |
90 | * public values; see refs.h. | |
91 | */ | |
92 | ||
93 | /* | |
94 | * The field ref_entry->u.value.peeled of this value entry contains | |
95 | * the correct peeled value for the reference, which might be | |
96 | * null_sha1 if the reference is not a tag or if it is broken. | |
97 | */ | |
98 | #define REF_KNOWS_PEELED 0x10 | |
99 | ||
100 | /* ref_entry represents a directory of references */ | |
101 | #define REF_DIR 0x20 | |
102 | ||
103 | /* | |
104 | * Entry has not yet been read from disk (used only for REF_DIR | |
105 | * entries representing loose references) | |
106 | */ | |
107 | #define REF_INCOMPLETE 0x40 | |
108 | ||
109 | /* | |
110 | * A ref_entry represents either a reference or a "subdirectory" of | |
111 | * references. | |
112 | * | |
113 | * Each directory in the reference namespace is represented by a | |
114 | * ref_entry with (flags & REF_DIR) set and containing a subdir member | |
115 | * that holds the entries in that directory that have been read so | |
116 | * far. If (flags & REF_INCOMPLETE) is set, then the directory and | |
117 | * its subdirectories haven't been read yet. REF_INCOMPLETE is only | |
118 | * used for loose reference directories. | |
119 | * | |
120 | * References are represented by a ref_entry with (flags & REF_DIR) | |
121 | * unset and a value member that describes the reference's value. The | |
122 | * flag member is at the ref_entry level, but it is also needed to | |
123 | * interpret the contents of the value field (in other words, a | |
124 | * ref_value object is not very much use without the enclosing | |
125 | * ref_entry). | |
126 | * | |
127 | * Reference names cannot end with slash and directories' names are | |
128 | * always stored with a trailing slash (except for the top-level | |
129 | * directory, which is always denoted by ""). This has two nice | |
130 | * consequences: (1) when the entries in each subdir are sorted | |
131 | * lexicographically by name (as they usually are), the references in | |
132 | * a whole tree can be generated in lexicographic order by traversing | |
133 | * the tree in left-to-right, depth-first order; (2) the names of | |
134 | * references and subdirectories cannot conflict, and therefore the | |
135 | * presence of an empty subdirectory does not block the creation of a | |
136 | * similarly-named reference. (The fact that reference names with the | |
137 | * same leading components can conflict *with each other* is a | |
138 | * separate issue that is regulated by verify_refname_available().) | |
139 | * | |
140 | * Please note that the name field contains the fully-qualified | |
141 | * reference (or subdirectory) name. Space could be saved by only | |
142 | * storing the relative names. But that would require the full names | |
143 | * to be generated on the fly when iterating in do_for_each_ref(), and | |
144 | * would break callback functions, who have always been able to assume | |
145 | * that the name strings that they are passed will not be freed during | |
146 | * the iteration. | |
147 | */ | |
148 | struct ref_entry { | |
149 | unsigned char flag; /* ISSYMREF? ISPACKED? */ | |
150 | union { | |
151 | struct ref_value value; /* if not (flags&REF_DIR) */ | |
152 | struct ref_dir subdir; /* if (flags&REF_DIR) */ | |
153 | } u; | |
154 | /* | |
155 | * The full name of the reference (e.g., "refs/heads/master") | |
156 | * or the full name of the directory with a trailing slash | |
157 | * (e.g., "refs/heads/"): | |
158 | */ | |
159 | char name[FLEX_ARRAY]; | |
160 | }; | |
161 | ||
162 | static void read_loose_refs(const char *dirname, struct ref_dir *dir); | |
163 | static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len); | |
164 | static struct ref_entry *create_dir_entry(struct files_ref_store *ref_store, | |
165 | const char *dirname, size_t len, | |
166 | int incomplete); | |
167 | static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry); | |
168 | ||
169 | static struct ref_dir *get_ref_dir(struct ref_entry *entry) | |
170 | { | |
171 | struct ref_dir *dir; | |
172 | assert(entry->flag & REF_DIR); | |
173 | dir = &entry->u.subdir; | |
174 | if (entry->flag & REF_INCOMPLETE) { | |
175 | read_loose_refs(entry->name, dir); | |
176 | ||
177 | /* | |
178 | * Manually add refs/bisect, which, being | |
179 | * per-worktree, might not appear in the directory | |
180 | * listing for refs/ in the main repo. | |
181 | */ | |
182 | if (!strcmp(entry->name, "refs/")) { | |
183 | int pos = search_ref_dir(dir, "refs/bisect/", 12); | |
184 | if (pos < 0) { | |
185 | struct ref_entry *child_entry; | |
186 | child_entry = create_dir_entry(dir->ref_store, | |
187 | "refs/bisect/", | |
188 | 12, 1); | |
189 | add_entry_to_dir(dir, child_entry); | |
190 | read_loose_refs("refs/bisect", | |
191 | &child_entry->u.subdir); | |
192 | } | |
193 | } | |
194 | entry->flag &= ~REF_INCOMPLETE; | |
195 | } | |
196 | return dir; | |
197 | } | |
198 | ||
199 | static struct ref_entry *create_ref_entry(const char *refname, | |
200 | const unsigned char *sha1, int flag, | |
201 | int check_name) | |
202 | { | |
203 | struct ref_entry *ref; | |
204 | ||
205 | if (check_name && | |
206 | check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) | |
207 | die("Reference has invalid format: '%s'", refname); | |
208 | FLEX_ALLOC_STR(ref, name, refname); | |
209 | hashcpy(ref->u.value.oid.hash, sha1); | |
210 | oidclr(&ref->u.value.peeled); | |
211 | ref->flag = flag; | |
212 | return ref; | |
213 | } | |
214 | ||
215 | static void clear_ref_dir(struct ref_dir *dir); | |
216 | ||
217 | static void free_ref_entry(struct ref_entry *entry) | |
218 | { | |
219 | if (entry->flag & REF_DIR) { | |
220 | /* | |
221 | * Do not use get_ref_dir() here, as that might | |
222 | * trigger the reading of loose refs. | |
223 | */ | |
224 | clear_ref_dir(&entry->u.subdir); | |
225 | } | |
226 | free(entry); | |
227 | } | |
228 | ||
229 | /* | |
230 | * Add a ref_entry to the end of dir (unsorted). Entry is always | |
231 | * stored directly in dir; no recursion into subdirectories is | |
232 | * done. | |
233 | */ | |
234 | static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry) | |
235 | { | |
236 | ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc); | |
237 | dir->entries[dir->nr++] = entry; | |
238 | /* optimize for the case that entries are added in order */ | |
239 | if (dir->nr == 1 || | |
240 | (dir->nr == dir->sorted + 1 && | |
241 | strcmp(dir->entries[dir->nr - 2]->name, | |
242 | dir->entries[dir->nr - 1]->name) < 0)) | |
243 | dir->sorted = dir->nr; | |
244 | } | |
245 | ||
246 | /* | |
247 | * Clear and free all entries in dir, recursively. | |
248 | */ | |
249 | static void clear_ref_dir(struct ref_dir *dir) | |
250 | { | |
251 | int i; | |
252 | for (i = 0; i < dir->nr; i++) | |
253 | free_ref_entry(dir->entries[i]); | |
254 | free(dir->entries); | |
255 | dir->sorted = dir->nr = dir->alloc = 0; | |
256 | dir->entries = NULL; | |
257 | } | |
258 | ||
259 | /* | |
260 | * Create a struct ref_entry object for the specified dirname. | |
261 | * dirname is the name of the directory with a trailing slash (e.g., | |
262 | * "refs/heads/") or "" for the top-level directory. | |
263 | */ | |
264 | static struct ref_entry *create_dir_entry(struct files_ref_store *ref_store, | |
265 | const char *dirname, size_t len, | |
266 | int incomplete) | |
267 | { | |
268 | struct ref_entry *direntry; | |
269 | FLEX_ALLOC_MEM(direntry, name, dirname, len); | |
270 | direntry->u.subdir.ref_store = ref_store; | |
271 | direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0); | |
272 | return direntry; | |
273 | } | |
274 | ||
275 | static int ref_entry_cmp(const void *a, const void *b) | |
276 | { | |
277 | struct ref_entry *one = *(struct ref_entry **)a; | |
278 | struct ref_entry *two = *(struct ref_entry **)b; | |
279 | return strcmp(one->name, two->name); | |
280 | } | |
281 | ||
282 | static void sort_ref_dir(struct ref_dir *dir); | |
283 | ||
284 | struct string_slice { | |
285 | size_t len; | |
286 | const char *str; | |
287 | }; | |
288 | ||
289 | static int ref_entry_cmp_sslice(const void *key_, const void *ent_) | |
290 | { | |
291 | const struct string_slice *key = key_; | |
292 | const struct ref_entry *ent = *(const struct ref_entry * const *)ent_; | |
293 | int cmp = strncmp(key->str, ent->name, key->len); | |
294 | if (cmp) | |
295 | return cmp; | |
296 | return '\0' - (unsigned char)ent->name[key->len]; | |
297 | } | |
298 | ||
299 | /* | |
300 | * Return the index of the entry with the given refname from the | |
301 | * ref_dir (non-recursively), sorting dir if necessary. Return -1 if | |
302 | * no such entry is found. dir must already be complete. | |
303 | */ | |
304 | static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len) | |
305 | { | |
306 | struct ref_entry **r; | |
307 | struct string_slice key; | |
308 | ||
309 | if (refname == NULL || !dir->nr) | |
310 | return -1; | |
311 | ||
312 | sort_ref_dir(dir); | |
313 | key.len = len; | |
314 | key.str = refname; | |
315 | r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries), | |
316 | ref_entry_cmp_sslice); | |
317 | ||
318 | if (r == NULL) | |
319 | return -1; | |
320 | ||
321 | return r - dir->entries; | |
322 | } | |
323 | ||
324 | /* | |
325 | * Search for a directory entry directly within dir (without | |
326 | * recursing). Sort dir if necessary. subdirname must be a directory | |
327 | * name (i.e., end in '/'). If mkdir is set, then create the | |
328 | * directory if it is missing; otherwise, return NULL if the desired | |
329 | * directory cannot be found. dir must already be complete. | |
330 | */ | |
331 | static struct ref_dir *search_for_subdir(struct ref_dir *dir, | |
332 | const char *subdirname, size_t len, | |
333 | int mkdir) | |
334 | { | |
335 | int entry_index = search_ref_dir(dir, subdirname, len); | |
336 | struct ref_entry *entry; | |
337 | if (entry_index == -1) { | |
338 | if (!mkdir) | |
339 | return NULL; | |
340 | /* | |
341 | * Since dir is complete, the absence of a subdir | |
342 | * means that the subdir really doesn't exist; | |
343 | * therefore, create an empty record for it but mark | |
344 | * the record complete. | |
345 | */ | |
346 | entry = create_dir_entry(dir->ref_store, subdirname, len, 0); | |
347 | add_entry_to_dir(dir, entry); | |
348 | } else { | |
349 | entry = dir->entries[entry_index]; | |
350 | } | |
351 | return get_ref_dir(entry); | |
352 | } | |
353 | ||
354 | /* | |
355 | * If refname is a reference name, find the ref_dir within the dir | |
356 | * tree that should hold refname. If refname is a directory name | |
357 | * (i.e., ends in '/'), then return that ref_dir itself. dir must | |
358 | * represent the top-level directory and must already be complete. | |
359 | * Sort ref_dirs and recurse into subdirectories as necessary. If | |
360 | * mkdir is set, then create any missing directories; otherwise, | |
361 | * return NULL if the desired directory cannot be found. | |
362 | */ | |
363 | static struct ref_dir *find_containing_dir(struct ref_dir *dir, | |
364 | const char *refname, int mkdir) | |
365 | { | |
366 | const char *slash; | |
367 | for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { | |
368 | size_t dirnamelen = slash - refname + 1; | |
369 | struct ref_dir *subdir; | |
370 | subdir = search_for_subdir(dir, refname, dirnamelen, mkdir); | |
371 | if (!subdir) { | |
372 | dir = NULL; | |
373 | break; | |
374 | } | |
375 | dir = subdir; | |
376 | } | |
377 | ||
378 | return dir; | |
379 | } | |
380 | ||
381 | /* | |
382 | * Find the value entry with the given name in dir, sorting ref_dirs | |
383 | * and recursing into subdirectories as necessary. If the name is not | |
384 | * found or it corresponds to a directory entry, return NULL. | |
385 | */ | |
386 | static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname) | |
387 | { | |
388 | int entry_index; | |
389 | struct ref_entry *entry; | |
390 | dir = find_containing_dir(dir, refname, 0); | |
391 | if (!dir) | |
392 | return NULL; | |
393 | entry_index = search_ref_dir(dir, refname, strlen(refname)); | |
394 | if (entry_index == -1) | |
395 | return NULL; | |
396 | entry = dir->entries[entry_index]; | |
397 | return (entry->flag & REF_DIR) ? NULL : entry; | |
398 | } | |
399 | ||
400 | /* | |
401 | * Remove the entry with the given name from dir, recursing into | |
402 | * subdirectories as necessary. If refname is the name of a directory | |
403 | * (i.e., ends with '/'), then remove the directory and its contents. | |
404 | * If the removal was successful, return the number of entries | |
405 | * remaining in the directory entry that contained the deleted entry. | |
406 | * If the name was not found, return -1. Please note that this | |
407 | * function only deletes the entry from the cache; it does not delete | |
408 | * it from the filesystem or ensure that other cache entries (which | |
409 | * might be symbolic references to the removed entry) are updated. | |
410 | * Nor does it remove any containing dir entries that might be made | |
411 | * empty by the removal. dir must represent the top-level directory | |
412 | * and must already be complete. | |
413 | */ | |
414 | static int remove_entry(struct ref_dir *dir, const char *refname) | |
415 | { | |
416 | int refname_len = strlen(refname); | |
417 | int entry_index; | |
418 | struct ref_entry *entry; | |
419 | int is_dir = refname[refname_len - 1] == '/'; | |
420 | if (is_dir) { | |
421 | /* | |
422 | * refname represents a reference directory. Remove | |
423 | * the trailing slash; otherwise we will get the | |
424 | * directory *representing* refname rather than the | |
425 | * one *containing* it. | |
426 | */ | |
427 | char *dirname = xmemdupz(refname, refname_len - 1); | |
428 | dir = find_containing_dir(dir, dirname, 0); | |
429 | free(dirname); | |
430 | } else { | |
431 | dir = find_containing_dir(dir, refname, 0); | |
432 | } | |
433 | if (!dir) | |
434 | return -1; | |
435 | entry_index = search_ref_dir(dir, refname, refname_len); | |
436 | if (entry_index == -1) | |
437 | return -1; | |
438 | entry = dir->entries[entry_index]; | |
439 | ||
440 | memmove(&dir->entries[entry_index], | |
441 | &dir->entries[entry_index + 1], | |
442 | (dir->nr - entry_index - 1) * sizeof(*dir->entries) | |
443 | ); | |
444 | dir->nr--; | |
445 | if (dir->sorted > entry_index) | |
446 | dir->sorted--; | |
447 | free_ref_entry(entry); | |
448 | return dir->nr; | |
449 | } | |
450 | ||
451 | /* | |
452 | * Add a ref_entry to the ref_dir (unsorted), recursing into | |
453 | * subdirectories as necessary. dir must represent the top-level | |
454 | * directory. Return 0 on success. | |
455 | */ | |
456 | static int add_ref(struct ref_dir *dir, struct ref_entry *ref) | |
457 | { | |
458 | dir = find_containing_dir(dir, ref->name, 1); | |
459 | if (!dir) | |
460 | return -1; | |
461 | add_entry_to_dir(dir, ref); | |
462 | return 0; | |
463 | } | |
464 | ||
465 | /* | |
466 | * Emit a warning and return true iff ref1 and ref2 have the same name | |
467 | * and the same sha1. Die if they have the same name but different | |
468 | * sha1s. | |
469 | */ | |
470 | static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2) | |
471 | { | |
472 | if (strcmp(ref1->name, ref2->name)) | |
473 | return 0; | |
474 | ||
475 | /* Duplicate name; make sure that they don't conflict: */ | |
476 | ||
477 | if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) | |
478 | /* This is impossible by construction */ | |
479 | die("Reference directory conflict: %s", ref1->name); | |
480 | ||
481 | if (oidcmp(&ref1->u.value.oid, &ref2->u.value.oid)) | |
482 | die("Duplicated ref, and SHA1s don't match: %s", ref1->name); | |
483 | ||
484 | warning("Duplicated ref: %s", ref1->name); | |
485 | return 1; | |
486 | } | |
487 | ||
488 | /* | |
489 | * Sort the entries in dir non-recursively (if they are not already | |
490 | * sorted) and remove any duplicate entries. | |
491 | */ | |
492 | static void sort_ref_dir(struct ref_dir *dir) | |
493 | { | |
494 | int i, j; | |
495 | struct ref_entry *last = NULL; | |
496 | ||
497 | /* | |
498 | * This check also prevents passing a zero-length array to qsort(), | |
499 | * which is a problem on some platforms. | |
500 | */ | |
501 | if (dir->sorted == dir->nr) | |
502 | return; | |
503 | ||
504 | qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp); | |
505 | ||
506 | /* Remove any duplicates: */ | |
507 | for (i = 0, j = 0; j < dir->nr; j++) { | |
508 | struct ref_entry *entry = dir->entries[j]; | |
509 | if (last && is_dup_ref(last, entry)) | |
510 | free_ref_entry(entry); | |
511 | else | |
512 | last = dir->entries[i++] = entry; | |
513 | } | |
514 | dir->sorted = dir->nr = i; | |
515 | } | |
516 | ||
517 | /* | |
518 | * Return true if refname, which has the specified oid and flags, can | |
519 | * be resolved to an object in the database. If the referred-to object | |
520 | * does not exist, emit a warning and return false. | |
521 | */ | |
522 | static int ref_resolves_to_object(const char *refname, | |
523 | const struct object_id *oid, | |
524 | unsigned int flags) | |
525 | { | |
526 | if (flags & REF_ISBROKEN) | |
527 | return 0; | |
528 | if (!has_sha1_file(oid->hash)) { | |
529 | error("%s does not point to a valid object!", refname); | |
530 | return 0; | |
531 | } | |
532 | return 1; | |
533 | } | |
534 | ||
535 | /* | |
536 | * Return true if the reference described by entry can be resolved to | |
537 | * an object in the database; otherwise, emit a warning and return | |
538 | * false. | |
539 | */ | |
540 | static int entry_resolves_to_object(struct ref_entry *entry) | |
541 | { | |
542 | return ref_resolves_to_object(entry->name, | |
543 | &entry->u.value.oid, entry->flag); | |
544 | } | |
545 | ||
546 | typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data); | |
547 | ||
548 | /* | |
549 | * Call fn for each reference in dir that has index in the range | |
550 | * offset <= index < dir->nr. Recurse into subdirectories that are in | |
551 | * that index range, sorting them before iterating. This function | |
552 | * does not sort dir itself; it should be sorted beforehand. fn is | |
553 | * called for all references, including broken ones. | |
554 | */ | |
555 | static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset, | |
556 | each_ref_entry_fn fn, void *cb_data) | |
557 | { | |
558 | int i; | |
559 | assert(dir->sorted == dir->nr); | |
560 | for (i = offset; i < dir->nr; i++) { | |
561 | struct ref_entry *entry = dir->entries[i]; | |
562 | int retval; | |
563 | if (entry->flag & REF_DIR) { | |
564 | struct ref_dir *subdir = get_ref_dir(entry); | |
565 | sort_ref_dir(subdir); | |
566 | retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data); | |
567 | } else { | |
568 | retval = fn(entry, cb_data); | |
569 | } | |
570 | if (retval) | |
571 | return retval; | |
572 | } | |
573 | return 0; | |
574 | } | |
575 | ||
576 | /* | |
577 | * Load all of the refs from the dir into our in-memory cache. The hard work | |
578 | * of loading loose refs is done by get_ref_dir(), so we just need to recurse | |
579 | * through all of the sub-directories. We do not even need to care about | |
580 | * sorting, as traversal order does not matter to us. | |
581 | */ | |
582 | static void prime_ref_dir(struct ref_dir *dir) | |
583 | { | |
584 | int i; | |
585 | for (i = 0; i < dir->nr; i++) { | |
586 | struct ref_entry *entry = dir->entries[i]; | |
587 | if (entry->flag & REF_DIR) | |
588 | prime_ref_dir(get_ref_dir(entry)); | |
589 | } | |
590 | } | |
591 | ||
592 | /* | |
593 | * A level in the reference hierarchy that is currently being iterated | |
594 | * through. | |
595 | */ | |
596 | struct cache_ref_iterator_level { | |
597 | /* | |
598 | * The ref_dir being iterated over at this level. The ref_dir | |
599 | * is sorted before being stored here. | |
600 | */ | |
601 | struct ref_dir *dir; | |
602 | ||
603 | /* | |
604 | * The index of the current entry within dir (which might | |
605 | * itself be a directory). If index == -1, then the iteration | |
606 | * hasn't yet begun. If index == dir->nr, then the iteration | |
607 | * through this level is over. | |
608 | */ | |
609 | int index; | |
610 | }; | |
611 | ||
612 | /* | |
613 | * Represent an iteration through a ref_dir in the memory cache. The | |
614 | * iteration recurses through subdirectories. | |
615 | */ | |
616 | struct cache_ref_iterator { | |
617 | struct ref_iterator base; | |
618 | ||
619 | /* | |
620 | * The number of levels currently on the stack. This is always | |
621 | * at least 1, because when it becomes zero the iteration is | |
622 | * ended and this struct is freed. | |
623 | */ | |
624 | size_t levels_nr; | |
625 | ||
626 | /* The number of levels that have been allocated on the stack */ | |
627 | size_t levels_alloc; | |
628 | ||
629 | /* | |
630 | * A stack of levels. levels[0] is the uppermost level that is | |
631 | * being iterated over in this iteration. (This is not | |
632 | * necessary the top level in the references hierarchy. If we | |
633 | * are iterating through a subtree, then levels[0] will hold | |
634 | * the ref_dir for that subtree, and subsequent levels will go | |
635 | * on from there.) | |
636 | */ | |
637 | struct cache_ref_iterator_level *levels; | |
638 | }; | |
639 | ||
640 | static int cache_ref_iterator_advance(struct ref_iterator *ref_iterator) | |
641 | { | |
642 | struct cache_ref_iterator *iter = | |
643 | (struct cache_ref_iterator *)ref_iterator; | |
644 | ||
645 | while (1) { | |
646 | struct cache_ref_iterator_level *level = | |
647 | &iter->levels[iter->levels_nr - 1]; | |
648 | struct ref_dir *dir = level->dir; | |
649 | struct ref_entry *entry; | |
650 | ||
651 | if (level->index == -1) | |
652 | sort_ref_dir(dir); | |
653 | ||
654 | if (++level->index == level->dir->nr) { | |
655 | /* This level is exhausted; pop up a level */ | |
656 | if (--iter->levels_nr == 0) | |
657 | return ref_iterator_abort(ref_iterator); | |
658 | ||
659 | continue; | |
660 | } | |
661 | ||
662 | entry = dir->entries[level->index]; | |
663 | ||
664 | if (entry->flag & REF_DIR) { | |
665 | /* push down a level */ | |
666 | ALLOC_GROW(iter->levels, iter->levels_nr + 1, | |
667 | iter->levels_alloc); | |
668 | ||
669 | level = &iter->levels[iter->levels_nr++]; | |
670 | level->dir = get_ref_dir(entry); | |
671 | level->index = -1; | |
672 | } else { | |
673 | iter->base.refname = entry->name; | |
674 | iter->base.oid = &entry->u.value.oid; | |
675 | iter->base.flags = entry->flag; | |
676 | return ITER_OK; | |
677 | } | |
678 | } | |
679 | } | |
680 | ||
681 | static enum peel_status peel_entry(struct ref_entry *entry, int repeel); | |
682 | ||
683 | static int cache_ref_iterator_peel(struct ref_iterator *ref_iterator, | |
684 | struct object_id *peeled) | |
685 | { | |
686 | struct cache_ref_iterator *iter = | |
687 | (struct cache_ref_iterator *)ref_iterator; | |
688 | struct cache_ref_iterator_level *level; | |
689 | struct ref_entry *entry; | |
690 | ||
691 | level = &iter->levels[iter->levels_nr - 1]; | |
692 | ||
693 | if (level->index == -1) | |
694 | die("BUG: peel called before advance for cache iterator"); | |
695 | ||
696 | entry = level->dir->entries[level->index]; | |
697 | ||
698 | if (peel_entry(entry, 0)) | |
699 | return -1; | |
700 | hashcpy(peeled->hash, entry->u.value.peeled.hash); | |
701 | return 0; | |
702 | } | |
703 | ||
704 | static int cache_ref_iterator_abort(struct ref_iterator *ref_iterator) | |
705 | { | |
706 | struct cache_ref_iterator *iter = | |
707 | (struct cache_ref_iterator *)ref_iterator; | |
708 | ||
709 | free(iter->levels); | |
710 | base_ref_iterator_free(ref_iterator); | |
711 | return ITER_DONE; | |
712 | } | |
713 | ||
714 | static struct ref_iterator_vtable cache_ref_iterator_vtable = { | |
715 | cache_ref_iterator_advance, | |
716 | cache_ref_iterator_peel, | |
717 | cache_ref_iterator_abort | |
718 | }; | |
719 | ||
720 | static struct ref_iterator *cache_ref_iterator_begin(struct ref_dir *dir) | |
721 | { | |
722 | struct cache_ref_iterator *iter; | |
723 | struct ref_iterator *ref_iterator; | |
724 | struct cache_ref_iterator_level *level; | |
725 | ||
726 | iter = xcalloc(1, sizeof(*iter)); | |
727 | ref_iterator = &iter->base; | |
728 | base_ref_iterator_init(ref_iterator, &cache_ref_iterator_vtable); | |
729 | ALLOC_GROW(iter->levels, 10, iter->levels_alloc); | |
730 | ||
731 | iter->levels_nr = 1; | |
732 | level = &iter->levels[0]; | |
733 | level->index = -1; | |
734 | level->dir = dir; | |
735 | ||
736 | return ref_iterator; | |
737 | } | |
738 | ||
739 | struct nonmatching_ref_data { | |
740 | const struct string_list *skip; | |
741 | const char *conflicting_refname; | |
742 | }; | |
743 | ||
744 | static int nonmatching_ref_fn(struct ref_entry *entry, void *vdata) | |
745 | { | |
746 | struct nonmatching_ref_data *data = vdata; | |
747 | ||
748 | if (data->skip && string_list_has_string(data->skip, entry->name)) | |
749 | return 0; | |
750 | ||
751 | data->conflicting_refname = entry->name; | |
752 | return 1; | |
753 | } | |
754 | ||
755 | /* | |
756 | * Return 0 if a reference named refname could be created without | |
757 | * conflicting with the name of an existing reference in dir. | |
758 | * See verify_refname_available for more information. | |
759 | */ | |
760 | static int verify_refname_available_dir(const char *refname, | |
761 | const struct string_list *extras, | |
762 | const struct string_list *skip, | |
763 | struct ref_dir *dir, | |
764 | struct strbuf *err) | |
765 | { | |
766 | const char *slash; | |
767 | const char *extra_refname; | |
768 | int pos; | |
769 | struct strbuf dirname = STRBUF_INIT; | |
770 | int ret = -1; | |
771 | ||
772 | /* | |
773 | * For the sake of comments in this function, suppose that | |
774 | * refname is "refs/foo/bar". | |
775 | */ | |
776 | ||
777 | assert(err); | |
778 | ||
779 | strbuf_grow(&dirname, strlen(refname) + 1); | |
780 | for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { | |
781 | /* Expand dirname to the new prefix, not including the trailing slash: */ | |
782 | strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len); | |
783 | ||
784 | /* | |
785 | * We are still at a leading dir of the refname (e.g., | |
786 | * "refs/foo"; if there is a reference with that name, | |
787 | * it is a conflict, *unless* it is in skip. | |
788 | */ | |
789 | if (dir) { | |
790 | pos = search_ref_dir(dir, dirname.buf, dirname.len); | |
791 | if (pos >= 0 && | |
792 | (!skip || !string_list_has_string(skip, dirname.buf))) { | |
793 | /* | |
794 | * We found a reference whose name is | |
795 | * a proper prefix of refname; e.g., | |
796 | * "refs/foo", and is not in skip. | |
797 | */ | |
798 | strbuf_addf(err, "'%s' exists; cannot create '%s'", | |
799 | dirname.buf, refname); | |
800 | goto cleanup; | |
801 | } | |
802 | } | |
803 | ||
804 | if (extras && string_list_has_string(extras, dirname.buf) && | |
805 | (!skip || !string_list_has_string(skip, dirname.buf))) { | |
806 | strbuf_addf(err, "cannot process '%s' and '%s' at the same time", | |
807 | refname, dirname.buf); | |
808 | goto cleanup; | |
809 | } | |
810 | ||
811 | /* | |
812 | * Otherwise, we can try to continue our search with | |
813 | * the next component. So try to look up the | |
814 | * directory, e.g., "refs/foo/". If we come up empty, | |
815 | * we know there is nothing under this whole prefix, | |
816 | * but even in that case we still have to continue the | |
817 | * search for conflicts with extras. | |
818 | */ | |
819 | strbuf_addch(&dirname, '/'); | |
820 | if (dir) { | |
821 | pos = search_ref_dir(dir, dirname.buf, dirname.len); | |
822 | if (pos < 0) { | |
823 | /* | |
824 | * There was no directory "refs/foo/", | |
825 | * so there is nothing under this | |
826 | * whole prefix. So there is no need | |
827 | * to continue looking for conflicting | |
828 | * references. But we need to continue | |
829 | * looking for conflicting extras. | |
830 | */ | |
831 | dir = NULL; | |
832 | } else { | |
833 | dir = get_ref_dir(dir->entries[pos]); | |
834 | } | |
835 | } | |
836 | } | |
837 | ||
838 | /* | |
839 | * We are at the leaf of our refname (e.g., "refs/foo/bar"). | |
840 | * There is no point in searching for a reference with that | |
841 | * name, because a refname isn't considered to conflict with | |
842 | * itself. But we still need to check for references whose | |
843 | * names are in the "refs/foo/bar/" namespace, because they | |
844 | * *do* conflict. | |
845 | */ | |
846 | strbuf_addstr(&dirname, refname + dirname.len); | |
847 | strbuf_addch(&dirname, '/'); | |
848 | ||
849 | if (dir) { | |
850 | pos = search_ref_dir(dir, dirname.buf, dirname.len); | |
851 | ||
852 | if (pos >= 0) { | |
853 | /* | |
854 | * We found a directory named "$refname/" | |
855 | * (e.g., "refs/foo/bar/"). It is a problem | |
856 | * iff it contains any ref that is not in | |
857 | * "skip". | |
858 | */ | |
859 | struct nonmatching_ref_data data; | |
860 | ||
861 | data.skip = skip; | |
862 | data.conflicting_refname = NULL; | |
863 | dir = get_ref_dir(dir->entries[pos]); | |
864 | sort_ref_dir(dir); | |
865 | if (do_for_each_entry_in_dir(dir, 0, nonmatching_ref_fn, &data)) { | |
866 | strbuf_addf(err, "'%s' exists; cannot create '%s'", | |
867 | data.conflicting_refname, refname); | |
868 | goto cleanup; | |
869 | } | |
870 | } | |
871 | } | |
872 | ||
873 | extra_refname = find_descendant_ref(dirname.buf, extras, skip); | |
874 | if (extra_refname) | |
875 | strbuf_addf(err, "cannot process '%s' and '%s' at the same time", | |
876 | refname, extra_refname); | |
877 | else | |
878 | ret = 0; | |
879 | ||
880 | cleanup: | |
881 | strbuf_release(&dirname); | |
882 | return ret; | |
883 | } | |
884 | ||
885 | struct packed_ref_cache { | |
886 | struct ref_entry *root; | |
887 | ||
888 | /* | |
889 | * Count of references to the data structure in this instance, | |
890 | * including the pointer from files_ref_store::packed if any. | |
891 | * The data will not be freed as long as the reference count | |
892 | * is nonzero. | |
893 | */ | |
894 | unsigned int referrers; | |
895 | ||
896 | /* | |
897 | * Iff the packed-refs file associated with this instance is | |
898 | * currently locked for writing, this points at the associated | |
899 | * lock (which is owned by somebody else). The referrer count | |
900 | * is also incremented when the file is locked and decremented | |
901 | * when it is unlocked. | |
902 | */ | |
903 | struct lock_file *lock; | |
904 | ||
905 | /* The metadata from when this packed-refs cache was read */ | |
906 | struct stat_validity validity; | |
907 | }; | |
908 | ||
909 | /* | |
910 | * Future: need to be in "struct repository" | |
911 | * when doing a full libification. | |
912 | */ | |
913 | static struct files_ref_store { | |
914 | struct files_ref_store *next; | |
915 | struct ref_entry *loose; | |
916 | struct packed_ref_cache *packed; | |
917 | /* | |
918 | * The submodule name, or "" for the main repo. We allocate | |
919 | * length 1 rather than FLEX_ARRAY so that the main | |
920 | * files_ref_store is initialized correctly. | |
921 | */ | |
922 | char name[1]; | |
923 | } ref_store, *submodule_ref_stores; | |
924 | ||
925 | /* Lock used for the main packed-refs file: */ | |
926 | static struct lock_file packlock; | |
927 | ||
928 | /* | |
929 | * Increment the reference count of *packed_refs. | |
930 | */ | |
931 | static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs) | |
932 | { | |
933 | packed_refs->referrers++; | |
934 | } | |
935 | ||
936 | /* | |
937 | * Decrease the reference count of *packed_refs. If it goes to zero, | |
938 | * free *packed_refs and return true; otherwise return false. | |
939 | */ | |
940 | static int release_packed_ref_cache(struct packed_ref_cache *packed_refs) | |
941 | { | |
942 | if (!--packed_refs->referrers) { | |
943 | free_ref_entry(packed_refs->root); | |
944 | stat_validity_clear(&packed_refs->validity); | |
945 | free(packed_refs); | |
946 | return 1; | |
947 | } else { | |
948 | return 0; | |
949 | } | |
950 | } | |
951 | ||
952 | static void clear_packed_ref_cache(struct files_ref_store *refs) | |
953 | { | |
954 | if (refs->packed) { | |
955 | struct packed_ref_cache *packed_refs = refs->packed; | |
956 | ||
957 | if (packed_refs->lock) | |
958 | die("internal error: packed-ref cache cleared while locked"); | |
959 | refs->packed = NULL; | |
960 | release_packed_ref_cache(packed_refs); | |
961 | } | |
962 | } | |
963 | ||
964 | static void clear_loose_ref_cache(struct files_ref_store *refs) | |
965 | { | |
966 | if (refs->loose) { | |
967 | free_ref_entry(refs->loose); | |
968 | refs->loose = NULL; | |
969 | } | |
970 | } | |
971 | ||
972 | /* | |
973 | * Create a new submodule ref cache and add it to the internal | |
974 | * set of caches. | |
975 | */ | |
976 | static struct files_ref_store *create_ref_store(const char *submodule) | |
977 | { | |
978 | struct files_ref_store *refs; | |
979 | if (!submodule) | |
980 | submodule = ""; | |
981 | FLEX_ALLOC_STR(refs, name, submodule); | |
982 | refs->next = submodule_ref_stores; | |
983 | submodule_ref_stores = refs; | |
984 | return refs; | |
985 | } | |
986 | ||
987 | static struct files_ref_store *lookup_ref_store(const char *submodule) | |
988 | { | |
989 | struct files_ref_store *refs; | |
990 | ||
991 | if (!submodule || !*submodule) | |
992 | return &ref_store; | |
993 | ||
994 | for (refs = submodule_ref_stores; refs; refs = refs->next) | |
995 | if (!strcmp(submodule, refs->name)) | |
996 | return refs; | |
997 | return NULL; | |
998 | } | |
999 | ||
1000 | /* | |
1001 | * Return a pointer to a files_ref_store for the specified submodule. For | |
1002 | * the main repository, use submodule==NULL; such a call cannot fail. | |
1003 | * For a submodule, the submodule must exist and be a nonbare | |
1004 | * repository, otherwise return NULL. | |
1005 | * | |
1006 | * The returned structure will be allocated and initialized but not | |
1007 | * necessarily populated; it should not be freed. | |
1008 | */ | |
1009 | static struct files_ref_store *get_ref_store(const char *submodule) | |
1010 | { | |
1011 | struct files_ref_store *refs = lookup_ref_store(submodule); | |
1012 | ||
1013 | if (!refs) { | |
1014 | struct strbuf submodule_sb = STRBUF_INIT; | |
1015 | ||
1016 | strbuf_addstr(&submodule_sb, submodule); | |
1017 | if (is_nonbare_repository_dir(&submodule_sb)) | |
1018 | refs = create_ref_store(submodule); | |
1019 | strbuf_release(&submodule_sb); | |
1020 | } | |
1021 | ||
1022 | return refs; | |
1023 | } | |
1024 | ||
1025 | /* The length of a peeled reference line in packed-refs, including EOL: */ | |
1026 | #define PEELED_LINE_LENGTH 42 | |
1027 | ||
1028 | /* | |
1029 | * The packed-refs header line that we write out. Perhaps other | |
1030 | * traits will be added later. The trailing space is required. | |
1031 | */ | |
1032 | static const char PACKED_REFS_HEADER[] = | |
1033 | "# pack-refs with: peeled fully-peeled \n"; | |
1034 | ||
1035 | /* | |
1036 | * Parse one line from a packed-refs file. Write the SHA1 to sha1. | |
1037 | * Return a pointer to the refname within the line (null-terminated), | |
1038 | * or NULL if there was a problem. | |
1039 | */ | |
1040 | static const char *parse_ref_line(struct strbuf *line, unsigned char *sha1) | |
1041 | { | |
1042 | const char *ref; | |
1043 | ||
1044 | /* | |
1045 | * 42: the answer to everything. | |
1046 | * | |
1047 | * In this case, it happens to be the answer to | |
1048 | * 40 (length of sha1 hex representation) | |
1049 | * +1 (space in between hex and name) | |
1050 | * +1 (newline at the end of the line) | |
1051 | */ | |
1052 | if (line->len <= 42) | |
1053 | return NULL; | |
1054 | ||
1055 | if (get_sha1_hex(line->buf, sha1) < 0) | |
1056 | return NULL; | |
1057 | if (!isspace(line->buf[40])) | |
1058 | return NULL; | |
1059 | ||
1060 | ref = line->buf + 41; | |
1061 | if (isspace(*ref)) | |
1062 | return NULL; | |
1063 | ||
1064 | if (line->buf[line->len - 1] != '\n') | |
1065 | return NULL; | |
1066 | line->buf[--line->len] = 0; | |
1067 | ||
1068 | return ref; | |
1069 | } | |
1070 | ||
1071 | /* | |
1072 | * Read f, which is a packed-refs file, into dir. | |
1073 | * | |
1074 | * A comment line of the form "# pack-refs with: " may contain zero or | |
1075 | * more traits. We interpret the traits as follows: | |
1076 | * | |
1077 | * No traits: | |
1078 | * | |
1079 | * Probably no references are peeled. But if the file contains a | |
1080 | * peeled value for a reference, we will use it. | |
1081 | * | |
1082 | * peeled: | |
1083 | * | |
1084 | * References under "refs/tags/", if they *can* be peeled, *are* | |
1085 | * peeled in this file. References outside of "refs/tags/" are | |
1086 | * probably not peeled even if they could have been, but if we find | |
1087 | * a peeled value for such a reference we will use it. | |
1088 | * | |
1089 | * fully-peeled: | |
1090 | * | |
1091 | * All references in the file that can be peeled are peeled. | |
1092 | * Inversely (and this is more important), any references in the | |
1093 | * file for which no peeled value is recorded is not peelable. This | |
1094 | * trait should typically be written alongside "peeled" for | |
1095 | * compatibility with older clients, but we do not require it | |
1096 | * (i.e., "peeled" is a no-op if "fully-peeled" is set). | |
1097 | */ | |
1098 | static void read_packed_refs(FILE *f, struct ref_dir *dir) | |
1099 | { | |
1100 | struct ref_entry *last = NULL; | |
1101 | struct strbuf line = STRBUF_INIT; | |
1102 | enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; | |
1103 | ||
1104 | while (strbuf_getwholeline(&line, f, '\n') != EOF) { | |
1105 | unsigned char sha1[20]; | |
1106 | const char *refname; | |
1107 | const char *traits; | |
1108 | ||
1109 | if (skip_prefix(line.buf, "# pack-refs with:", &traits)) { | |
1110 | if (strstr(traits, " fully-peeled ")) | |
1111 | peeled = PEELED_FULLY; | |
1112 | else if (strstr(traits, " peeled ")) | |
1113 | peeled = PEELED_TAGS; | |
1114 | /* perhaps other traits later as well */ | |
1115 | continue; | |
1116 | } | |
1117 | ||
1118 | refname = parse_ref_line(&line, sha1); | |
1119 | if (refname) { | |
1120 | int flag = REF_ISPACKED; | |
1121 | ||
1122 | if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { | |
1123 | if (!refname_is_safe(refname)) | |
1124 | die("packed refname is dangerous: %s", refname); | |
1125 | hashclr(sha1); | |
1126 | flag |= REF_BAD_NAME | REF_ISBROKEN; | |
1127 | } | |
1128 | last = create_ref_entry(refname, sha1, flag, 0); | |
1129 | if (peeled == PEELED_FULLY || | |
1130 | (peeled == PEELED_TAGS && starts_with(refname, "refs/tags/"))) | |
1131 | last->flag |= REF_KNOWS_PEELED; | |
1132 | add_ref(dir, last); | |
1133 | continue; | |
1134 | } | |
1135 | if (last && | |
1136 | line.buf[0] == '^' && | |
1137 | line.len == PEELED_LINE_LENGTH && | |
1138 | line.buf[PEELED_LINE_LENGTH - 1] == '\n' && | |
1139 | !get_sha1_hex(line.buf + 1, sha1)) { | |
1140 | hashcpy(last->u.value.peeled.hash, sha1); | |
1141 | /* | |
1142 | * Regardless of what the file header said, | |
1143 | * we definitely know the value of *this* | |
1144 | * reference: | |
1145 | */ | |
1146 | last->flag |= REF_KNOWS_PEELED; | |
1147 | } | |
1148 | } | |
1149 | ||
1150 | strbuf_release(&line); | |
1151 | } | |
1152 | ||
1153 | /* | |
1154 | * Get the packed_ref_cache for the specified files_ref_store, | |
1155 | * creating it if necessary. | |
1156 | */ | |
1157 | static struct packed_ref_cache *get_packed_ref_cache(struct files_ref_store *refs) | |
1158 | { | |
1159 | char *packed_refs_file; | |
1160 | ||
1161 | if (*refs->name) | |
1162 | packed_refs_file = git_pathdup_submodule(refs->name, "packed-refs"); | |
1163 | else | |
1164 | packed_refs_file = git_pathdup("packed-refs"); | |
1165 | ||
1166 | if (refs->packed && | |
1167 | !stat_validity_check(&refs->packed->validity, packed_refs_file)) | |
1168 | clear_packed_ref_cache(refs); | |
1169 | ||
1170 | if (!refs->packed) { | |
1171 | FILE *f; | |
1172 | ||
1173 | refs->packed = xcalloc(1, sizeof(*refs->packed)); | |
1174 | acquire_packed_ref_cache(refs->packed); | |
1175 | refs->packed->root = create_dir_entry(refs, "", 0, 0); | |
1176 | f = fopen(packed_refs_file, "r"); | |
1177 | if (f) { | |
1178 | stat_validity_update(&refs->packed->validity, fileno(f)); | |
1179 | read_packed_refs(f, get_ref_dir(refs->packed->root)); | |
1180 | fclose(f); | |
1181 | } | |
1182 | } | |
1183 | free(packed_refs_file); | |
1184 | return refs->packed; | |
1185 | } | |
1186 | ||
1187 | static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache) | |
1188 | { | |
1189 | return get_ref_dir(packed_ref_cache->root); | |
1190 | } | |
1191 | ||
1192 | static struct ref_dir *get_packed_refs(struct files_ref_store *refs) | |
1193 | { | |
1194 | return get_packed_ref_dir(get_packed_ref_cache(refs)); | |
1195 | } | |
1196 | ||
1197 | /* | |
1198 | * Add a reference to the in-memory packed reference cache. This may | |
1199 | * only be called while the packed-refs file is locked (see | |
1200 | * lock_packed_refs()). To actually write the packed-refs file, call | |
1201 | * commit_packed_refs(). | |
1202 | */ | |
1203 | static void add_packed_ref(const char *refname, const unsigned char *sha1) | |
1204 | { | |
1205 | struct packed_ref_cache *packed_ref_cache = | |
1206 | get_packed_ref_cache(&ref_store); | |
1207 | ||
1208 | if (!packed_ref_cache->lock) | |
1209 | die("internal error: packed refs not locked"); | |
1210 | add_ref(get_packed_ref_dir(packed_ref_cache), | |
1211 | create_ref_entry(refname, sha1, REF_ISPACKED, 1)); | |
1212 | } | |
1213 | ||
1214 | /* | |
1215 | * Read the loose references from the namespace dirname into dir | |
1216 | * (without recursing). dirname must end with '/'. dir must be the | |
1217 | * directory entry corresponding to dirname. | |
1218 | */ | |
1219 | static void read_loose_refs(const char *dirname, struct ref_dir *dir) | |
1220 | { | |
1221 | struct files_ref_store *refs = dir->ref_store; | |
1222 | DIR *d; | |
1223 | struct dirent *de; | |
1224 | int dirnamelen = strlen(dirname); | |
1225 | struct strbuf refname; | |
1226 | struct strbuf path = STRBUF_INIT; | |
1227 | size_t path_baselen; | |
1228 | ||
1229 | if (*refs->name) | |
1230 | strbuf_git_path_submodule(&path, refs->name, "%s", dirname); | |
1231 | else | |
1232 | strbuf_git_path(&path, "%s", dirname); | |
1233 | path_baselen = path.len; | |
1234 | ||
1235 | d = opendir(path.buf); | |
1236 | if (!d) { | |
1237 | strbuf_release(&path); | |
1238 | return; | |
1239 | } | |
1240 | ||
1241 | strbuf_init(&refname, dirnamelen + 257); | |
1242 | strbuf_add(&refname, dirname, dirnamelen); | |
1243 | ||
1244 | while ((de = readdir(d)) != NULL) { | |
1245 | unsigned char sha1[20]; | |
1246 | struct stat st; | |
1247 | int flag; | |
1248 | ||
1249 | if (de->d_name[0] == '.') | |
1250 | continue; | |
1251 | if (ends_with(de->d_name, ".lock")) | |
1252 | continue; | |
1253 | strbuf_addstr(&refname, de->d_name); | |
1254 | strbuf_addstr(&path, de->d_name); | |
1255 | if (stat(path.buf, &st) < 0) { | |
1256 | ; /* silently ignore */ | |
1257 | } else if (S_ISDIR(st.st_mode)) { | |
1258 | strbuf_addch(&refname, '/'); | |
1259 | add_entry_to_dir(dir, | |
1260 | create_dir_entry(refs, refname.buf, | |
1261 | refname.len, 1)); | |
1262 | } else { | |
1263 | int read_ok; | |
1264 | ||
1265 | if (*refs->name) { | |
1266 | hashclr(sha1); | |
1267 | flag = 0; | |
1268 | read_ok = !resolve_gitlink_ref(refs->name, | |
1269 | refname.buf, sha1); | |
1270 | } else { | |
1271 | read_ok = !read_ref_full(refname.buf, | |
1272 | RESOLVE_REF_READING, | |
1273 | sha1, &flag); | |
1274 | } | |
1275 | ||
1276 | if (!read_ok) { | |
1277 | hashclr(sha1); | |
1278 | flag |= REF_ISBROKEN; | |
1279 | } else if (is_null_sha1(sha1)) { | |
1280 | /* | |
1281 | * It is so astronomically unlikely | |
1282 | * that NULL_SHA1 is the SHA-1 of an | |
1283 | * actual object that we consider its | |
1284 | * appearance in a loose reference | |
1285 | * file to be repo corruption | |
1286 | * (probably due to a software bug). | |
1287 | */ | |
1288 | flag |= REF_ISBROKEN; | |
1289 | } | |
1290 | ||
1291 | if (check_refname_format(refname.buf, | |
1292 | REFNAME_ALLOW_ONELEVEL)) { | |
1293 | if (!refname_is_safe(refname.buf)) | |
1294 | die("loose refname is dangerous: %s", refname.buf); | |
1295 | hashclr(sha1); | |
1296 | flag |= REF_BAD_NAME | REF_ISBROKEN; | |
1297 | } | |
1298 | add_entry_to_dir(dir, | |
1299 | create_ref_entry(refname.buf, sha1, flag, 0)); | |
1300 | } | |
1301 | strbuf_setlen(&refname, dirnamelen); | |
1302 | strbuf_setlen(&path, path_baselen); | |
1303 | } | |
1304 | strbuf_release(&refname); | |
1305 | strbuf_release(&path); | |
1306 | closedir(d); | |
1307 | } | |
1308 | ||
1309 | static struct ref_dir *get_loose_refs(struct files_ref_store *refs) | |
1310 | { | |
1311 | if (!refs->loose) { | |
1312 | /* | |
1313 | * Mark the top-level directory complete because we | |
1314 | * are about to read the only subdirectory that can | |
1315 | * hold references: | |
1316 | */ | |
1317 | refs->loose = create_dir_entry(refs, "", 0, 0); | |
1318 | /* | |
1319 | * Create an incomplete entry for "refs/": | |
1320 | */ | |
1321 | add_entry_to_dir(get_ref_dir(refs->loose), | |
1322 | create_dir_entry(refs, "refs/", 5, 1)); | |
1323 | } | |
1324 | return get_ref_dir(refs->loose); | |
1325 | } | |
1326 | ||
1327 | #define MAXREFLEN (1024) | |
1328 | ||
1329 | /* | |
1330 | * Called by resolve_gitlink_ref_recursive() after it failed to read | |
1331 | * from the loose refs in refs. Find <refname> in the packed-refs file | |
1332 | * for the submodule. | |
1333 | */ | |
1334 | static int resolve_gitlink_packed_ref(struct files_ref_store *refs, | |
1335 | const char *refname, unsigned char *sha1) | |
1336 | { | |
1337 | struct ref_entry *ref; | |
1338 | struct ref_dir *dir = get_packed_refs(refs); | |
1339 | ||
1340 | ref = find_ref(dir, refname); | |
1341 | if (ref == NULL) | |
1342 | return -1; | |
1343 | ||
1344 | hashcpy(sha1, ref->u.value.oid.hash); | |
1345 | return 0; | |
1346 | } | |
1347 | ||
1348 | static int resolve_gitlink_ref_recursive(struct files_ref_store *refs, | |
1349 | const char *refname, unsigned char *sha1, | |
1350 | int recursion) | |
1351 | { | |
1352 | int fd, len; | |
1353 | char buffer[128], *p; | |
1354 | char *path; | |
1355 | ||
1356 | if (recursion > SYMREF_MAXDEPTH || strlen(refname) > MAXREFLEN) | |
1357 | return -1; | |
1358 | path = *refs->name | |
1359 | ? git_pathdup_submodule(refs->name, "%s", refname) | |
1360 | : git_pathdup("%s", refname); | |
1361 | fd = open(path, O_RDONLY); | |
1362 | free(path); | |
1363 | if (fd < 0) | |
1364 | return resolve_gitlink_packed_ref(refs, refname, sha1); | |
1365 | ||
1366 | len = read(fd, buffer, sizeof(buffer)-1); | |
1367 | close(fd); | |
1368 | if (len < 0) | |
1369 | return -1; | |
1370 | while (len && isspace(buffer[len-1])) | |
1371 | len--; | |
1372 | buffer[len] = 0; | |
1373 | ||
1374 | /* Was it a detached head or an old-fashioned symlink? */ | |
1375 | if (!get_sha1_hex(buffer, sha1)) | |
1376 | return 0; | |
1377 | ||
1378 | /* Symref? */ | |
1379 | if (strncmp(buffer, "ref:", 4)) | |
1380 | return -1; | |
1381 | p = buffer + 4; | |
1382 | while (isspace(*p)) | |
1383 | p++; | |
1384 | ||
1385 | return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1); | |
1386 | } | |
1387 | ||
1388 | int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1) | |
1389 | { | |
1390 | int len = strlen(path); | |
1391 | struct strbuf submodule = STRBUF_INIT; | |
1392 | struct files_ref_store *refs; | |
1393 | ||
1394 | while (len && path[len-1] == '/') | |
1395 | len--; | |
1396 | if (!len) | |
1397 | return -1; | |
1398 | ||
1399 | strbuf_add(&submodule, path, len); | |
1400 | refs = get_ref_store(submodule.buf); | |
1401 | if (!refs) { | |
1402 | strbuf_release(&submodule); | |
1403 | return -1; | |
1404 | } | |
1405 | strbuf_release(&submodule); | |
1406 | ||
1407 | return resolve_gitlink_ref_recursive(refs, refname, sha1, 0); | |
1408 | } | |
1409 | ||
1410 | /* | |
1411 | * Return the ref_entry for the given refname from the packed | |
1412 | * references. If it does not exist, return NULL. | |
1413 | */ | |
1414 | static struct ref_entry *get_packed_ref(const char *refname) | |
1415 | { | |
1416 | return find_ref(get_packed_refs(&ref_store), refname); | |
1417 | } | |
1418 | ||
1419 | /* | |
1420 | * A loose ref file doesn't exist; check for a packed ref. | |
1421 | */ | |
1422 | static int resolve_missing_loose_ref(const char *refname, | |
1423 | unsigned char *sha1, | |
1424 | unsigned int *flags) | |
1425 | { | |
1426 | struct ref_entry *entry; | |
1427 | ||
1428 | /* | |
1429 | * The loose reference file does not exist; check for a packed | |
1430 | * reference. | |
1431 | */ | |
1432 | entry = get_packed_ref(refname); | |
1433 | if (entry) { | |
1434 | hashcpy(sha1, entry->u.value.oid.hash); | |
1435 | *flags |= REF_ISPACKED; | |
1436 | return 0; | |
1437 | } | |
1438 | /* refname is not a packed reference. */ | |
1439 | return -1; | |
1440 | } | |
1441 | ||
1442 | int read_raw_ref(const char *refname, unsigned char *sha1, | |
1443 | struct strbuf *referent, unsigned int *type) | |
1444 | { | |
1445 | struct strbuf sb_contents = STRBUF_INIT; | |
1446 | struct strbuf sb_path = STRBUF_INIT; | |
1447 | const char *path; | |
1448 | const char *buf; | |
1449 | struct stat st; | |
1450 | int fd; | |
1451 | int ret = -1; | |
1452 | int save_errno; | |
1453 | ||
1454 | *type = 0; | |
1455 | strbuf_reset(&sb_path); | |
1456 | strbuf_git_path(&sb_path, "%s", refname); | |
1457 | path = sb_path.buf; | |
1458 | ||
1459 | stat_ref: | |
1460 | /* | |
1461 | * We might have to loop back here to avoid a race | |
1462 | * condition: first we lstat() the file, then we try | |
1463 | * to read it as a link or as a file. But if somebody | |
1464 | * changes the type of the file (file <-> directory | |
1465 | * <-> symlink) between the lstat() and reading, then | |
1466 | * we don't want to report that as an error but rather | |
1467 | * try again starting with the lstat(). | |
1468 | */ | |
1469 | ||
1470 | if (lstat(path, &st) < 0) { | |
1471 | if (errno != ENOENT) | |
1472 | goto out; | |
1473 | if (resolve_missing_loose_ref(refname, sha1, type)) { | |
1474 | errno = ENOENT; | |
1475 | goto out; | |
1476 | } | |
1477 | ret = 0; | |
1478 | goto out; | |
1479 | } | |
1480 | ||
1481 | /* Follow "normalized" - ie "refs/.." symlinks by hand */ | |
1482 | if (S_ISLNK(st.st_mode)) { | |
1483 | strbuf_reset(&sb_contents); | |
1484 | if (strbuf_readlink(&sb_contents, path, 0) < 0) { | |
1485 | if (errno == ENOENT || errno == EINVAL) | |
1486 | /* inconsistent with lstat; retry */ | |
1487 | goto stat_ref; | |
1488 | else | |
1489 | goto out; | |
1490 | } | |
1491 | if (starts_with(sb_contents.buf, "refs/") && | |
1492 | !check_refname_format(sb_contents.buf, 0)) { | |
1493 | strbuf_swap(&sb_contents, referent); | |
1494 | *type |= REF_ISSYMREF; | |
1495 | ret = 0; | |
1496 | goto out; | |
1497 | } | |
1498 | } | |
1499 | ||
1500 | /* Is it a directory? */ | |
1501 | if (S_ISDIR(st.st_mode)) { | |
1502 | /* | |
1503 | * Even though there is a directory where the loose | |
1504 | * ref is supposed to be, there could still be a | |
1505 | * packed ref: | |
1506 | */ | |
1507 | if (resolve_missing_loose_ref(refname, sha1, type)) { | |
1508 | errno = EISDIR; | |
1509 | goto out; | |
1510 | } | |
1511 | ret = 0; | |
1512 | goto out; | |
1513 | } | |
1514 | ||
1515 | /* | |
1516 | * Anything else, just open it and try to use it as | |
1517 | * a ref | |
1518 | */ | |
1519 | fd = open(path, O_RDONLY); | |
1520 | if (fd < 0) { | |
1521 | if (errno == ENOENT) | |
1522 | /* inconsistent with lstat; retry */ | |
1523 | goto stat_ref; | |
1524 | else | |
1525 | goto out; | |
1526 | } | |
1527 | strbuf_reset(&sb_contents); | |
1528 | if (strbuf_read(&sb_contents, fd, 256) < 0) { | |
1529 | int save_errno = errno; | |
1530 | close(fd); | |
1531 | errno = save_errno; | |
1532 | goto out; | |
1533 | } | |
1534 | close(fd); | |
1535 | strbuf_rtrim(&sb_contents); | |
1536 | buf = sb_contents.buf; | |
1537 | if (starts_with(buf, "ref:")) { | |
1538 | buf += 4; | |
1539 | while (isspace(*buf)) | |
1540 | buf++; | |
1541 | ||
1542 | strbuf_reset(referent); | |
1543 | strbuf_addstr(referent, buf); | |
1544 | *type |= REF_ISSYMREF; | |
1545 | ret = 0; | |
1546 | goto out; | |
1547 | } | |
1548 | ||
1549 | /* | |
1550 | * Please note that FETCH_HEAD has additional | |
1551 | * data after the sha. | |
1552 | */ | |
1553 | if (get_sha1_hex(buf, sha1) || | |
1554 | (buf[40] != '\0' && !isspace(buf[40]))) { | |
1555 | *type |= REF_ISBROKEN; | |
1556 | errno = EINVAL; | |
1557 | goto out; | |
1558 | } | |
1559 | ||
1560 | ret = 0; | |
1561 | ||
1562 | out: | |
1563 | save_errno = errno; | |
1564 | strbuf_release(&sb_path); | |
1565 | strbuf_release(&sb_contents); | |
1566 | errno = save_errno; | |
1567 | return ret; | |
1568 | } | |
1569 | ||
1570 | static void unlock_ref(struct ref_lock *lock) | |
1571 | { | |
1572 | /* Do not free lock->lk -- atexit() still looks at them */ | |
1573 | if (lock->lk) | |
1574 | rollback_lock_file(lock->lk); | |
1575 | free(lock->ref_name); | |
1576 | free(lock); | |
1577 | } | |
1578 | ||
1579 | /* | |
1580 | * Lock refname, without following symrefs, and set *lock_p to point | |
1581 | * at a newly-allocated lock object. Fill in lock->old_oid, referent, | |
1582 | * and type similarly to read_raw_ref(). | |
1583 | * | |
1584 | * The caller must verify that refname is a "safe" reference name (in | |
1585 | * the sense of refname_is_safe()) before calling this function. | |
1586 | * | |
1587 | * If the reference doesn't already exist, verify that refname doesn't | |
1588 | * have a D/F conflict with any existing references. extras and skip | |
1589 | * are passed to verify_refname_available_dir() for this check. | |
1590 | * | |
1591 | * If mustexist is not set and the reference is not found or is | |
1592 | * broken, lock the reference anyway but clear sha1. | |
1593 | * | |
1594 | * Return 0 on success. On failure, write an error message to err and | |
1595 | * return TRANSACTION_NAME_CONFLICT or TRANSACTION_GENERIC_ERROR. | |
1596 | * | |
1597 | * Implementation note: This function is basically | |
1598 | * | |
1599 | * lock reference | |
1600 | * read_raw_ref() | |
1601 | * | |
1602 | * but it includes a lot more code to | |
1603 | * - Deal with possible races with other processes | |
1604 | * - Avoid calling verify_refname_available_dir() when it can be | |
1605 | * avoided, namely if we were successfully able to read the ref | |
1606 | * - Generate informative error messages in the case of failure | |
1607 | */ | |
1608 | static int lock_raw_ref(const char *refname, int mustexist, | |
1609 | const struct string_list *extras, | |
1610 | const struct string_list *skip, | |
1611 | struct ref_lock **lock_p, | |
1612 | struct strbuf *referent, | |
1613 | unsigned int *type, | |
1614 | struct strbuf *err) | |
1615 | { | |
1616 | struct ref_lock *lock; | |
1617 | struct strbuf ref_file = STRBUF_INIT; | |
1618 | int attempts_remaining = 3; | |
1619 | int ret = TRANSACTION_GENERIC_ERROR; | |
1620 | ||
1621 | assert(err); | |
1622 | *type = 0; | |
1623 | ||
1624 | /* First lock the file so it can't change out from under us. */ | |
1625 | ||
1626 | *lock_p = lock = xcalloc(1, sizeof(*lock)); | |
1627 | ||
1628 | lock->ref_name = xstrdup(refname); | |
1629 | strbuf_git_path(&ref_file, "%s", refname); | |
1630 | ||
1631 | retry: | |
1632 | switch (safe_create_leading_directories(ref_file.buf)) { | |
1633 | case SCLD_OK: | |
1634 | break; /* success */ | |
1635 | case SCLD_EXISTS: | |
1636 | /* | |
1637 | * Suppose refname is "refs/foo/bar". We just failed | |
1638 | * to create the containing directory, "refs/foo", | |
1639 | * because there was a non-directory in the way. This | |
1640 | * indicates a D/F conflict, probably because of | |
1641 | * another reference such as "refs/foo". There is no | |
1642 | * reason to expect this error to be transitory. | |
1643 | */ | |
1644 | if (verify_refname_available(refname, extras, skip, err)) { | |
1645 | if (mustexist) { | |
1646 | /* | |
1647 | * To the user the relevant error is | |
1648 | * that the "mustexist" reference is | |
1649 | * missing: | |
1650 | */ | |
1651 | strbuf_reset(err); | |
1652 | strbuf_addf(err, "unable to resolve reference '%s'", | |
1653 | refname); | |
1654 | } else { | |
1655 | /* | |
1656 | * The error message set by | |
1657 | * verify_refname_available_dir() is OK. | |
1658 | */ | |
1659 | ret = TRANSACTION_NAME_CONFLICT; | |
1660 | } | |
1661 | } else { | |
1662 | /* | |
1663 | * The file that is in the way isn't a loose | |
1664 | * reference. Report it as a low-level | |
1665 | * failure. | |
1666 | */ | |
1667 | strbuf_addf(err, "unable to create lock file %s.lock; " | |
1668 | "non-directory in the way", | |
1669 | ref_file.buf); | |
1670 | } | |
1671 | goto error_return; | |
1672 | case SCLD_VANISHED: | |
1673 | /* Maybe another process was tidying up. Try again. */ | |
1674 | if (--attempts_remaining > 0) | |
1675 | goto retry; | |
1676 | /* fall through */ | |
1677 | default: | |
1678 | strbuf_addf(err, "unable to create directory for %s", | |
1679 | ref_file.buf); | |
1680 | goto error_return; | |
1681 | } | |
1682 | ||
1683 | if (!lock->lk) | |
1684 | lock->lk = xcalloc(1, sizeof(struct lock_file)); | |
1685 | ||
1686 | if (hold_lock_file_for_update(lock->lk, ref_file.buf, LOCK_NO_DEREF) < 0) { | |
1687 | if (errno == ENOENT && --attempts_remaining > 0) { | |
1688 | /* | |
1689 | * Maybe somebody just deleted one of the | |
1690 | * directories leading to ref_file. Try | |
1691 | * again: | |
1692 | */ | |
1693 | goto retry; | |
1694 | } else { | |
1695 | unable_to_lock_message(ref_file.buf, errno, err); | |
1696 | goto error_return; | |
1697 | } | |
1698 | } | |
1699 | ||
1700 | /* | |
1701 | * Now we hold the lock and can read the reference without | |
1702 | * fear that its value will change. | |
1703 | */ | |
1704 | ||
1705 | if (read_raw_ref(refname, lock->old_oid.hash, referent, type)) { | |
1706 | if (errno == ENOENT) { | |
1707 | if (mustexist) { | |
1708 | /* Garden variety missing reference. */ | |
1709 | strbuf_addf(err, "unable to resolve reference '%s'", | |
1710 | refname); | |
1711 | goto error_return; | |
1712 | } else { | |
1713 | /* | |
1714 | * Reference is missing, but that's OK. We | |
1715 | * know that there is not a conflict with | |
1716 | * another loose reference because | |
1717 | * (supposing that we are trying to lock | |
1718 | * reference "refs/foo/bar"): | |
1719 | * | |
1720 | * - We were successfully able to create | |
1721 | * the lockfile refs/foo/bar.lock, so we | |
1722 | * know there cannot be a loose reference | |
1723 | * named "refs/foo". | |
1724 | * | |
1725 | * - We got ENOENT and not EISDIR, so we | |
1726 | * know that there cannot be a loose | |
1727 | * reference named "refs/foo/bar/baz". | |
1728 | */ | |
1729 | } | |
1730 | } else if (errno == EISDIR) { | |
1731 | /* | |
1732 | * There is a directory in the way. It might have | |
1733 | * contained references that have been deleted. If | |
1734 | * we don't require that the reference already | |
1735 | * exists, try to remove the directory so that it | |
1736 | * doesn't cause trouble when we want to rename the | |
1737 | * lockfile into place later. | |
1738 | */ | |
1739 | if (mustexist) { | |
1740 | /* Garden variety missing reference. */ | |
1741 | strbuf_addf(err, "unable to resolve reference '%s'", | |
1742 | refname); | |
1743 | goto error_return; | |
1744 | } else if (remove_dir_recursively(&ref_file, | |
1745 | REMOVE_DIR_EMPTY_ONLY)) { | |
1746 | if (verify_refname_available_dir( | |
1747 | refname, extras, skip, | |
1748 | get_loose_refs(&ref_store), | |
1749 | err)) { | |
1750 | /* | |
1751 | * The error message set by | |
1752 | * verify_refname_available() is OK. | |
1753 | */ | |
1754 | ret = TRANSACTION_NAME_CONFLICT; | |
1755 | goto error_return; | |
1756 | } else { | |
1757 | /* | |
1758 | * We can't delete the directory, | |
1759 | * but we also don't know of any | |
1760 | * references that it should | |
1761 | * contain. | |
1762 | */ | |
1763 | strbuf_addf(err, "there is a non-empty directory '%s' " | |
1764 | "blocking reference '%s'", | |
1765 | ref_file.buf, refname); | |
1766 | goto error_return; | |
1767 | } | |
1768 | } | |
1769 | } else if (errno == EINVAL && (*type & REF_ISBROKEN)) { | |
1770 | strbuf_addf(err, "unable to resolve reference '%s': " | |
1771 | "reference broken", refname); | |
1772 | goto error_return; | |
1773 | } else { | |
1774 | strbuf_addf(err, "unable to resolve reference '%s': %s", | |
1775 | refname, strerror(errno)); | |
1776 | goto error_return; | |
1777 | } | |
1778 | ||
1779 | /* | |
1780 | * If the ref did not exist and we are creating it, | |
1781 | * make sure there is no existing packed ref whose | |
1782 | * name begins with our refname, nor a packed ref | |
1783 | * whose name is a proper prefix of our refname. | |
1784 | */ | |
1785 | if (verify_refname_available_dir( | |
1786 | refname, extras, skip, | |
1787 | get_packed_refs(&ref_store), | |
1788 | err)) { | |
1789 | goto error_return; | |
1790 | } | |
1791 | } | |
1792 | ||
1793 | ret = 0; | |
1794 | goto out; | |
1795 | ||
1796 | error_return: | |
1797 | unlock_ref(lock); | |
1798 | *lock_p = NULL; | |
1799 | ||
1800 | out: | |
1801 | strbuf_release(&ref_file); | |
1802 | return ret; | |
1803 | } | |
1804 | ||
1805 | /* | |
1806 | * Peel the entry (if possible) and return its new peel_status. If | |
1807 | * repeel is true, re-peel the entry even if there is an old peeled | |
1808 | * value that is already stored in it. | |
1809 | * | |
1810 | * It is OK to call this function with a packed reference entry that | |
1811 | * might be stale and might even refer to an object that has since | |
1812 | * been garbage-collected. In such a case, if the entry has | |
1813 | * REF_KNOWS_PEELED then leave the status unchanged and return | |
1814 | * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID. | |
1815 | */ | |
1816 | static enum peel_status peel_entry(struct ref_entry *entry, int repeel) | |
1817 | { | |
1818 | enum peel_status status; | |
1819 | ||
1820 | if (entry->flag & REF_KNOWS_PEELED) { | |
1821 | if (repeel) { | |
1822 | entry->flag &= ~REF_KNOWS_PEELED; | |
1823 | oidclr(&entry->u.value.peeled); | |
1824 | } else { | |
1825 | return is_null_oid(&entry->u.value.peeled) ? | |
1826 | PEEL_NON_TAG : PEEL_PEELED; | |
1827 | } | |
1828 | } | |
1829 | if (entry->flag & REF_ISBROKEN) | |
1830 | return PEEL_BROKEN; | |
1831 | if (entry->flag & REF_ISSYMREF) | |
1832 | return PEEL_IS_SYMREF; | |
1833 | ||
1834 | status = peel_object(entry->u.value.oid.hash, entry->u.value.peeled.hash); | |
1835 | if (status == PEEL_PEELED || status == PEEL_NON_TAG) | |
1836 | entry->flag |= REF_KNOWS_PEELED; | |
1837 | return status; | |
1838 | } | |
1839 | ||
1840 | int peel_ref(const char *refname, unsigned char *sha1) | |
1841 | { | |
1842 | int flag; | |
1843 | unsigned char base[20]; | |
1844 | ||
1845 | if (current_ref_iter && current_ref_iter->refname == refname) { | |
1846 | struct object_id peeled; | |
1847 | ||
1848 | if (ref_iterator_peel(current_ref_iter, &peeled)) | |
1849 | return -1; | |
1850 | hashcpy(sha1, peeled.hash); | |
1851 | return 0; | |
1852 | } | |
1853 | ||
1854 | if (read_ref_full(refname, RESOLVE_REF_READING, base, &flag)) | |
1855 | return -1; | |
1856 | ||
1857 | /* | |
1858 | * If the reference is packed, read its ref_entry from the | |
1859 | * cache in the hope that we already know its peeled value. | |
1860 | * We only try this optimization on packed references because | |
1861 | * (a) forcing the filling of the loose reference cache could | |
1862 | * be expensive and (b) loose references anyway usually do not | |
1863 | * have REF_KNOWS_PEELED. | |
1864 | */ | |
1865 | if (flag & REF_ISPACKED) { | |
1866 | struct ref_entry *r = get_packed_ref(refname); | |
1867 | if (r) { | |
1868 | if (peel_entry(r, 0)) | |
1869 | return -1; | |
1870 | hashcpy(sha1, r->u.value.peeled.hash); | |
1871 | return 0; | |
1872 | } | |
1873 | } | |
1874 | ||
1875 | return peel_object(base, sha1); | |
1876 | } | |
1877 | ||
1878 | struct files_ref_iterator { | |
1879 | struct ref_iterator base; | |
1880 | ||
1881 | struct packed_ref_cache *packed_ref_cache; | |
1882 | struct ref_iterator *iter0; | |
1883 | unsigned int flags; | |
1884 | }; | |
1885 | ||
1886 | static int files_ref_iterator_advance(struct ref_iterator *ref_iterator) | |
1887 | { | |
1888 | struct files_ref_iterator *iter = | |
1889 | (struct files_ref_iterator *)ref_iterator; | |
1890 | int ok; | |
1891 | ||
1892 | while ((ok = ref_iterator_advance(iter->iter0)) == ITER_OK) { | |
1893 | if (!(iter->flags & DO_FOR_EACH_INCLUDE_BROKEN) && | |
1894 | !ref_resolves_to_object(iter->iter0->refname, | |
1895 | iter->iter0->oid, | |
1896 | iter->iter0->flags)) | |
1897 | continue; | |
1898 | ||
1899 | iter->base.refname = iter->iter0->refname; | |
1900 | iter->base.oid = iter->iter0->oid; | |
1901 | iter->base.flags = iter->iter0->flags; | |
1902 | return ITER_OK; | |
1903 | } | |
1904 | ||
1905 | iter->iter0 = NULL; | |
1906 | if (ref_iterator_abort(ref_iterator) != ITER_DONE) | |
1907 | ok = ITER_ERROR; | |
1908 | ||
1909 | return ok; | |
1910 | } | |
1911 | ||
1912 | static int files_ref_iterator_peel(struct ref_iterator *ref_iterator, | |
1913 | struct object_id *peeled) | |
1914 | { | |
1915 | struct files_ref_iterator *iter = | |
1916 | (struct files_ref_iterator *)ref_iterator; | |
1917 | ||
1918 | return ref_iterator_peel(iter->iter0, peeled); | |
1919 | } | |
1920 | ||
1921 | static int files_ref_iterator_abort(struct ref_iterator *ref_iterator) | |
1922 | { | |
1923 | struct files_ref_iterator *iter = | |
1924 | (struct files_ref_iterator *)ref_iterator; | |
1925 | int ok = ITER_DONE; | |
1926 | ||
1927 | if (iter->iter0) | |
1928 | ok = ref_iterator_abort(iter->iter0); | |
1929 | ||
1930 | release_packed_ref_cache(iter->packed_ref_cache); | |
1931 | base_ref_iterator_free(ref_iterator); | |
1932 | return ok; | |
1933 | } | |
1934 | ||
1935 | static struct ref_iterator_vtable files_ref_iterator_vtable = { | |
1936 | files_ref_iterator_advance, | |
1937 | files_ref_iterator_peel, | |
1938 | files_ref_iterator_abort | |
1939 | }; | |
1940 | ||
1941 | struct ref_iterator *files_ref_iterator_begin( | |
1942 | const char *submodule, | |
1943 | const char *prefix, unsigned int flags) | |
1944 | { | |
1945 | struct files_ref_store *refs = get_ref_store(submodule); | |
1946 | struct ref_dir *loose_dir, *packed_dir; | |
1947 | struct ref_iterator *loose_iter, *packed_iter; | |
1948 | struct files_ref_iterator *iter; | |
1949 | struct ref_iterator *ref_iterator; | |
1950 | ||
1951 | if (!refs) | |
1952 | return empty_ref_iterator_begin(); | |
1953 | ||
1954 | if (ref_paranoia < 0) | |
1955 | ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0); | |
1956 | if (ref_paranoia) | |
1957 | flags |= DO_FOR_EACH_INCLUDE_BROKEN; | |
1958 | ||
1959 | iter = xcalloc(1, sizeof(*iter)); | |
1960 | ref_iterator = &iter->base; | |
1961 | base_ref_iterator_init(ref_iterator, &files_ref_iterator_vtable); | |
1962 | ||
1963 | /* | |
1964 | * We must make sure that all loose refs are read before | |
1965 | * accessing the packed-refs file; this avoids a race | |
1966 | * condition if loose refs are migrated to the packed-refs | |
1967 | * file by a simultaneous process, but our in-memory view is | |
1968 | * from before the migration. We ensure this as follows: | |
1969 | * First, we call prime_ref_dir(), which pre-reads the loose | |
1970 | * references for the subtree into the cache. (If they've | |
1971 | * already been read, that's OK; we only need to guarantee | |
1972 | * that they're read before the packed refs, not *how much* | |
1973 | * before.) After that, we call get_packed_ref_cache(), which | |
1974 | * internally checks whether the packed-ref cache is up to | |
1975 | * date with what is on disk, and re-reads it if not. | |
1976 | */ | |
1977 | ||
1978 | loose_dir = get_loose_refs(refs); | |
1979 | ||
1980 | if (prefix && *prefix) | |
1981 | loose_dir = find_containing_dir(loose_dir, prefix, 0); | |
1982 | ||
1983 | if (loose_dir) { | |
1984 | prime_ref_dir(loose_dir); | |
1985 | loose_iter = cache_ref_iterator_begin(loose_dir); | |
1986 | } else { | |
1987 | /* There's nothing to iterate over. */ | |
1988 | loose_iter = empty_ref_iterator_begin(); | |
1989 | } | |
1990 | ||
1991 | iter->packed_ref_cache = get_packed_ref_cache(refs); | |
1992 | acquire_packed_ref_cache(iter->packed_ref_cache); | |
1993 | packed_dir = get_packed_ref_dir(iter->packed_ref_cache); | |
1994 | ||
1995 | if (prefix && *prefix) | |
1996 | packed_dir = find_containing_dir(packed_dir, prefix, 0); | |
1997 | ||
1998 | if (packed_dir) { | |
1999 | packed_iter = cache_ref_iterator_begin(packed_dir); | |
2000 | } else { | |
2001 | /* There's nothing to iterate over. */ | |
2002 | packed_iter = empty_ref_iterator_begin(); | |
2003 | } | |
2004 | ||
2005 | iter->iter0 = overlay_ref_iterator_begin(loose_iter, packed_iter); | |
2006 | iter->flags = flags; | |
2007 | ||
2008 | return ref_iterator; | |
2009 | } | |
2010 | ||
2011 | /* | |
2012 | * Verify that the reference locked by lock has the value old_sha1. | |
2013 | * Fail if the reference doesn't exist and mustexist is set. Return 0 | |
2014 | * on success. On error, write an error message to err, set errno, and | |
2015 | * return a negative value. | |
2016 | */ | |
2017 | static int verify_lock(struct ref_lock *lock, | |
2018 | const unsigned char *old_sha1, int mustexist, | |
2019 | struct strbuf *err) | |
2020 | { | |
2021 | assert(err); | |
2022 | ||
2023 | if (read_ref_full(lock->ref_name, | |
2024 | mustexist ? RESOLVE_REF_READING : 0, | |
2025 | lock->old_oid.hash, NULL)) { | |
2026 | if (old_sha1) { | |
2027 | int save_errno = errno; | |
2028 | strbuf_addf(err, "can't verify ref '%s'", lock->ref_name); | |
2029 | errno = save_errno; | |
2030 | return -1; | |
2031 | } else { | |
2032 | hashclr(lock->old_oid.hash); | |
2033 | return 0; | |
2034 | } | |
2035 | } | |
2036 | if (old_sha1 && hashcmp(lock->old_oid.hash, old_sha1)) { | |
2037 | strbuf_addf(err, "ref '%s' is at %s but expected %s", | |
2038 | lock->ref_name, | |
2039 | sha1_to_hex(lock->old_oid.hash), | |
2040 | sha1_to_hex(old_sha1)); | |
2041 | errno = EBUSY; | |
2042 | return -1; | |
2043 | } | |
2044 | return 0; | |
2045 | } | |
2046 | ||
2047 | static int remove_empty_directories(struct strbuf *path) | |
2048 | { | |
2049 | /* | |
2050 | * we want to create a file but there is a directory there; | |
2051 | * if that is an empty directory (or a directory that contains | |
2052 | * only empty directories), remove them. | |
2053 | */ | |
2054 | return remove_dir_recursively(path, REMOVE_DIR_EMPTY_ONLY); | |
2055 | } | |
2056 | ||
2057 | /* | |
2058 | * Locks a ref returning the lock on success and NULL on failure. | |
2059 | * On failure errno is set to something meaningful. | |
2060 | */ | |
2061 | static struct ref_lock *lock_ref_sha1_basic(const char *refname, | |
2062 | const unsigned char *old_sha1, | |
2063 | const struct string_list *extras, | |
2064 | const struct string_list *skip, | |
2065 | unsigned int flags, int *type, | |
2066 | struct strbuf *err) | |
2067 | { | |
2068 | struct strbuf ref_file = STRBUF_INIT; | |
2069 | struct ref_lock *lock; | |
2070 | int last_errno = 0; | |
2071 | int lflags = LOCK_NO_DEREF; | |
2072 | int mustexist = (old_sha1 && !is_null_sha1(old_sha1)); | |
2073 | int resolve_flags = RESOLVE_REF_NO_RECURSE; | |
2074 | int attempts_remaining = 3; | |
2075 | int resolved; | |
2076 | ||
2077 | assert(err); | |
2078 | ||
2079 | lock = xcalloc(1, sizeof(struct ref_lock)); | |
2080 | ||
2081 | if (mustexist) | |
2082 | resolve_flags |= RESOLVE_REF_READING; | |
2083 | if (flags & REF_DELETING) | |
2084 | resolve_flags |= RESOLVE_REF_ALLOW_BAD_NAME; | |
2085 | ||
2086 | strbuf_git_path(&ref_file, "%s", refname); | |
2087 | resolved = !!resolve_ref_unsafe(refname, resolve_flags, | |
2088 | lock->old_oid.hash, type); | |
2089 | if (!resolved && errno == EISDIR) { | |
2090 | /* | |
2091 | * we are trying to lock foo but we used to | |
2092 | * have foo/bar which now does not exist; | |
2093 | * it is normal for the empty directory 'foo' | |
2094 | * to remain. | |
2095 | */ | |
2096 | if (remove_empty_directories(&ref_file)) { | |
2097 | last_errno = errno; | |
2098 | if (!verify_refname_available_dir(refname, extras, skip, | |
2099 | get_loose_refs(&ref_store), err)) | |
2100 | strbuf_addf(err, "there are still refs under '%s'", | |
2101 | refname); | |
2102 | goto error_return; | |
2103 | } | |
2104 | resolved = !!resolve_ref_unsafe(refname, resolve_flags, | |
2105 | lock->old_oid.hash, type); | |
2106 | } | |
2107 | if (!resolved) { | |
2108 | last_errno = errno; | |
2109 | if (last_errno != ENOTDIR || | |
2110 | !verify_refname_available_dir(refname, extras, skip, | |
2111 | get_loose_refs(&ref_store), err)) | |
2112 | strbuf_addf(err, "unable to resolve reference '%s': %s", | |
2113 | refname, strerror(last_errno)); | |
2114 | ||
2115 | goto error_return; | |
2116 | } | |
2117 | ||
2118 | /* | |
2119 | * If the ref did not exist and we are creating it, make sure | |
2120 | * there is no existing packed ref whose name begins with our | |
2121 | * refname, nor a packed ref whose name is a proper prefix of | |
2122 | * our refname. | |
2123 | */ | |
2124 | if (is_null_oid(&lock->old_oid) && | |
2125 | verify_refname_available_dir(refname, extras, skip, | |
2126 | get_packed_refs(&ref_store), err)) { | |
2127 | last_errno = ENOTDIR; | |
2128 | goto error_return; | |
2129 | } | |
2130 | ||
2131 | lock->lk = xcalloc(1, sizeof(struct lock_file)); | |
2132 | ||
2133 | lock->ref_name = xstrdup(refname); | |
2134 | ||
2135 | retry: | |
2136 | switch (safe_create_leading_directories_const(ref_file.buf)) { | |
2137 | case SCLD_OK: | |
2138 | break; /* success */ | |
2139 | case SCLD_VANISHED: | |
2140 | if (--attempts_remaining > 0) | |
2141 | goto retry; | |
2142 | /* fall through */ | |
2143 | default: | |
2144 | last_errno = errno; | |
2145 | strbuf_addf(err, "unable to create directory for '%s'", | |
2146 | ref_file.buf); | |
2147 | goto error_return; | |
2148 | } | |
2149 | ||
2150 | if (hold_lock_file_for_update(lock->lk, ref_file.buf, lflags) < 0) { | |
2151 | last_errno = errno; | |
2152 | if (errno == ENOENT && --attempts_remaining > 0) | |
2153 | /* | |
2154 | * Maybe somebody just deleted one of the | |
2155 | * directories leading to ref_file. Try | |
2156 | * again: | |
2157 | */ | |
2158 | goto retry; | |
2159 | else { | |
2160 | unable_to_lock_message(ref_file.buf, errno, err); | |
2161 | goto error_return; | |
2162 | } | |
2163 | } | |
2164 | if (verify_lock(lock, old_sha1, mustexist, err)) { | |
2165 | last_errno = errno; | |
2166 | goto error_return; | |
2167 | } | |
2168 | goto out; | |
2169 | ||
2170 | error_return: | |
2171 | unlock_ref(lock); | |
2172 | lock = NULL; | |
2173 | ||
2174 | out: | |
2175 | strbuf_release(&ref_file); | |
2176 | errno = last_errno; | |
2177 | return lock; | |
2178 | } | |
2179 | ||
2180 | /* | |
2181 | * Write an entry to the packed-refs file for the specified refname. | |
2182 | * If peeled is non-NULL, write it as the entry's peeled value. | |
2183 | */ | |
2184 | static void write_packed_entry(FILE *fh, char *refname, unsigned char *sha1, | |
2185 | unsigned char *peeled) | |
2186 | { | |
2187 | fprintf_or_die(fh, "%s %s\n", sha1_to_hex(sha1), refname); | |
2188 | if (peeled) | |
2189 | fprintf_or_die(fh, "^%s\n", sha1_to_hex(peeled)); | |
2190 | } | |
2191 | ||
2192 | /* | |
2193 | * An each_ref_entry_fn that writes the entry to a packed-refs file. | |
2194 | */ | |
2195 | static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data) | |
2196 | { | |
2197 | enum peel_status peel_status = peel_entry(entry, 0); | |
2198 | ||
2199 | if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG) | |
2200 | error("internal error: %s is not a valid packed reference!", | |
2201 | entry->name); | |
2202 | write_packed_entry(cb_data, entry->name, entry->u.value.oid.hash, | |
2203 | peel_status == PEEL_PEELED ? | |
2204 | entry->u.value.peeled.hash : NULL); | |
2205 | return 0; | |
2206 | } | |
2207 | ||
2208 | /* | |
2209 | * Lock the packed-refs file for writing. Flags is passed to | |
2210 | * hold_lock_file_for_update(). Return 0 on success. On errors, set | |
2211 | * errno appropriately and return a nonzero value. | |
2212 | */ | |
2213 | static int lock_packed_refs(int flags) | |
2214 | { | |
2215 | static int timeout_configured = 0; | |
2216 | static int timeout_value = 1000; | |
2217 | ||
2218 | struct packed_ref_cache *packed_ref_cache; | |
2219 | ||
2220 | if (!timeout_configured) { | |
2221 | git_config_get_int("core.packedrefstimeout", &timeout_value); | |
2222 | timeout_configured = 1; | |
2223 | } | |
2224 | ||
2225 | if (hold_lock_file_for_update_timeout( | |
2226 | &packlock, git_path("packed-refs"), | |
2227 | flags, timeout_value) < 0) | |
2228 | return -1; | |
2229 | /* | |
2230 | * Get the current packed-refs while holding the lock. If the | |
2231 | * packed-refs file has been modified since we last read it, | |
2232 | * this will automatically invalidate the cache and re-read | |
2233 | * the packed-refs file. | |
2234 | */ | |
2235 | packed_ref_cache = get_packed_ref_cache(&ref_store); | |
2236 | packed_ref_cache->lock = &packlock; | |
2237 | /* Increment the reference count to prevent it from being freed: */ | |
2238 | acquire_packed_ref_cache(packed_ref_cache); | |
2239 | return 0; | |
2240 | } | |
2241 | ||
2242 | /* | |
2243 | * Write the current version of the packed refs cache from memory to | |
2244 | * disk. The packed-refs file must already be locked for writing (see | |
2245 | * lock_packed_refs()). Return zero on success. On errors, set errno | |
2246 | * and return a nonzero value | |
2247 | */ | |
2248 | static int commit_packed_refs(void) | |
2249 | { | |
2250 | struct packed_ref_cache *packed_ref_cache = | |
2251 | get_packed_ref_cache(&ref_store); | |
2252 | int error = 0; | |
2253 | int save_errno = 0; | |
2254 | FILE *out; | |
2255 | ||
2256 | if (!packed_ref_cache->lock) | |
2257 | die("internal error: packed-refs not locked"); | |
2258 | ||
2259 | out = fdopen_lock_file(packed_ref_cache->lock, "w"); | |
2260 | if (!out) | |
2261 | die_errno("unable to fdopen packed-refs descriptor"); | |
2262 | ||
2263 | fprintf_or_die(out, "%s", PACKED_REFS_HEADER); | |
2264 | do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache), | |
2265 | 0, write_packed_entry_fn, out); | |
2266 | ||
2267 | if (commit_lock_file(packed_ref_cache->lock)) { | |
2268 | save_errno = errno; | |
2269 | error = -1; | |
2270 | } | |
2271 | packed_ref_cache->lock = NULL; | |
2272 | release_packed_ref_cache(packed_ref_cache); | |
2273 | errno = save_errno; | |
2274 | return error; | |
2275 | } | |
2276 | ||
2277 | /* | |
2278 | * Rollback the lockfile for the packed-refs file, and discard the | |
2279 | * in-memory packed reference cache. (The packed-refs file will be | |
2280 | * read anew if it is needed again after this function is called.) | |
2281 | */ | |
2282 | static void rollback_packed_refs(void) | |
2283 | { | |
2284 | struct packed_ref_cache *packed_ref_cache = | |
2285 | get_packed_ref_cache(&ref_store); | |
2286 | ||
2287 | if (!packed_ref_cache->lock) | |
2288 | die("internal error: packed-refs not locked"); | |
2289 | rollback_lock_file(packed_ref_cache->lock); | |
2290 | packed_ref_cache->lock = NULL; | |
2291 | release_packed_ref_cache(packed_ref_cache); | |
2292 | clear_packed_ref_cache(&ref_store); | |
2293 | } | |
2294 | ||
2295 | struct ref_to_prune { | |
2296 | struct ref_to_prune *next; | |
2297 | unsigned char sha1[20]; | |
2298 | char name[FLEX_ARRAY]; | |
2299 | }; | |
2300 | ||
2301 | struct pack_refs_cb_data { | |
2302 | unsigned int flags; | |
2303 | struct ref_dir *packed_refs; | |
2304 | struct ref_to_prune *ref_to_prune; | |
2305 | }; | |
2306 | ||
2307 | /* | |
2308 | * An each_ref_entry_fn that is run over loose references only. If | |
2309 | * the loose reference can be packed, add an entry in the packed ref | |
2310 | * cache. If the reference should be pruned, also add it to | |
2311 | * ref_to_prune in the pack_refs_cb_data. | |
2312 | */ | |
2313 | static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data) | |
2314 | { | |
2315 | struct pack_refs_cb_data *cb = cb_data; | |
2316 | enum peel_status peel_status; | |
2317 | struct ref_entry *packed_entry; | |
2318 | int is_tag_ref = starts_with(entry->name, "refs/tags/"); | |
2319 | ||
2320 | /* Do not pack per-worktree refs: */ | |
2321 | if (ref_type(entry->name) != REF_TYPE_NORMAL) | |
2322 | return 0; | |
2323 | ||
2324 | /* ALWAYS pack tags */ | |
2325 | if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref) | |
2326 | return 0; | |
2327 | ||
2328 | /* Do not pack symbolic or broken refs: */ | |
2329 | if ((entry->flag & REF_ISSYMREF) || !entry_resolves_to_object(entry)) | |
2330 | return 0; | |
2331 | ||
2332 | /* Add a packed ref cache entry equivalent to the loose entry. */ | |
2333 | peel_status = peel_entry(entry, 1); | |
2334 | if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG) | |
2335 | die("internal error peeling reference %s (%s)", | |
2336 | entry->name, oid_to_hex(&entry->u.value.oid)); | |
2337 | packed_entry = find_ref(cb->packed_refs, entry->name); | |
2338 | if (packed_entry) { | |
2339 | /* Overwrite existing packed entry with info from loose entry */ | |
2340 | packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED; | |
2341 | oidcpy(&packed_entry->u.value.oid, &entry->u.value.oid); | |
2342 | } else { | |
2343 | packed_entry = create_ref_entry(entry->name, entry->u.value.oid.hash, | |
2344 | REF_ISPACKED | REF_KNOWS_PEELED, 0); | |
2345 | add_ref(cb->packed_refs, packed_entry); | |
2346 | } | |
2347 | oidcpy(&packed_entry->u.value.peeled, &entry->u.value.peeled); | |
2348 | ||
2349 | /* Schedule the loose reference for pruning if requested. */ | |
2350 | if ((cb->flags & PACK_REFS_PRUNE)) { | |
2351 | struct ref_to_prune *n; | |
2352 | FLEX_ALLOC_STR(n, name, entry->name); | |
2353 | hashcpy(n->sha1, entry->u.value.oid.hash); | |
2354 | n->next = cb->ref_to_prune; | |
2355 | cb->ref_to_prune = n; | |
2356 | } | |
2357 | return 0; | |
2358 | } | |
2359 | ||
2360 | /* | |
2361 | * Remove empty parents, but spare refs/ and immediate subdirs. | |
2362 | * Note: munges *name. | |
2363 | */ | |
2364 | static void try_remove_empty_parents(char *name) | |
2365 | { | |
2366 | char *p, *q; | |
2367 | int i; | |
2368 | p = name; | |
2369 | for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */ | |
2370 | while (*p && *p != '/') | |
2371 | p++; | |
2372 | /* tolerate duplicate slashes; see check_refname_format() */ | |
2373 | while (*p == '/') | |
2374 | p++; | |
2375 | } | |
2376 | for (q = p; *q; q++) | |
2377 | ; | |
2378 | while (1) { | |
2379 | while (q > p && *q != '/') | |
2380 | q--; | |
2381 | while (q > p && *(q-1) == '/') | |
2382 | q--; | |
2383 | if (q == p) | |
2384 | break; | |
2385 | *q = '\0'; | |
2386 | if (rmdir(git_path("%s", name))) | |
2387 | break; | |
2388 | } | |
2389 | } | |
2390 | ||
2391 | /* make sure nobody touched the ref, and unlink */ | |
2392 | static void prune_ref(struct ref_to_prune *r) | |
2393 | { | |
2394 | struct ref_transaction *transaction; | |
2395 | struct strbuf err = STRBUF_INIT; | |
2396 | ||
2397 | if (check_refname_format(r->name, 0)) | |
2398 | return; | |
2399 | ||
2400 | transaction = ref_transaction_begin(&err); | |
2401 | if (!transaction || | |
2402 | ref_transaction_delete(transaction, r->name, r->sha1, | |
2403 | REF_ISPRUNING | REF_NODEREF, NULL, &err) || | |
2404 | ref_transaction_commit(transaction, &err)) { | |
2405 | ref_transaction_free(transaction); | |
2406 | error("%s", err.buf); | |
2407 | strbuf_release(&err); | |
2408 | return; | |
2409 | } | |
2410 | ref_transaction_free(transaction); | |
2411 | strbuf_release(&err); | |
2412 | try_remove_empty_parents(r->name); | |
2413 | } | |
2414 | ||
2415 | static void prune_refs(struct ref_to_prune *r) | |
2416 | { | |
2417 | while (r) { | |
2418 | prune_ref(r); | |
2419 | r = r->next; | |
2420 | } | |
2421 | } | |
2422 | ||
2423 | int pack_refs(unsigned int flags) | |
2424 | { | |
2425 | struct pack_refs_cb_data cbdata; | |
2426 | ||
2427 | memset(&cbdata, 0, sizeof(cbdata)); | |
2428 | cbdata.flags = flags; | |
2429 | ||
2430 | lock_packed_refs(LOCK_DIE_ON_ERROR); | |
2431 | cbdata.packed_refs = get_packed_refs(&ref_store); | |
2432 | ||
2433 | do_for_each_entry_in_dir(get_loose_refs(&ref_store), 0, | |
2434 | pack_if_possible_fn, &cbdata); | |
2435 | ||
2436 | if (commit_packed_refs()) | |
2437 | die_errno("unable to overwrite old ref-pack file"); | |
2438 | ||
2439 | prune_refs(cbdata.ref_to_prune); | |
2440 | return 0; | |
2441 | } | |
2442 | ||
2443 | /* | |
2444 | * Rewrite the packed-refs file, omitting any refs listed in | |
2445 | * 'refnames'. On error, leave packed-refs unchanged, write an error | |
2446 | * message to 'err', and return a nonzero value. | |
2447 | * | |
2448 | * The refs in 'refnames' needn't be sorted. `err` must not be NULL. | |
2449 | */ | |
2450 | static int repack_without_refs(struct string_list *refnames, struct strbuf *err) | |
2451 | { | |
2452 | struct ref_dir *packed; | |
2453 | struct string_list_item *refname; | |
2454 | int ret, needs_repacking = 0, removed = 0; | |
2455 | ||
2456 | assert(err); | |
2457 | ||
2458 | /* Look for a packed ref */ | |
2459 | for_each_string_list_item(refname, refnames) { | |
2460 | if (get_packed_ref(refname->string)) { | |
2461 | needs_repacking = 1; | |
2462 | break; | |
2463 | } | |
2464 | } | |
2465 | ||
2466 | /* Avoid locking if we have nothing to do */ | |
2467 | if (!needs_repacking) | |
2468 | return 0; /* no refname exists in packed refs */ | |
2469 | ||
2470 | if (lock_packed_refs(0)) { | |
2471 | unable_to_lock_message(git_path("packed-refs"), errno, err); | |
2472 | return -1; | |
2473 | } | |
2474 | packed = get_packed_refs(&ref_store); | |
2475 | ||
2476 | /* Remove refnames from the cache */ | |
2477 | for_each_string_list_item(refname, refnames) | |
2478 | if (remove_entry(packed, refname->string) != -1) | |
2479 | removed = 1; | |
2480 | if (!removed) { | |
2481 | /* | |
2482 | * All packed entries disappeared while we were | |
2483 | * acquiring the lock. | |
2484 | */ | |
2485 | rollback_packed_refs(); | |
2486 | return 0; | |
2487 | } | |
2488 | ||
2489 | /* Write what remains */ | |
2490 | ret = commit_packed_refs(); | |
2491 | if (ret) | |
2492 | strbuf_addf(err, "unable to overwrite old ref-pack file: %s", | |
2493 | strerror(errno)); | |
2494 | return ret; | |
2495 | } | |
2496 | ||
2497 | static int delete_ref_loose(struct ref_lock *lock, int flag, struct strbuf *err) | |
2498 | { | |
2499 | assert(err); | |
2500 | ||
2501 | if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) { | |
2502 | /* | |
2503 | * loose. The loose file name is the same as the | |
2504 | * lockfile name, minus ".lock": | |
2505 | */ | |
2506 | char *loose_filename = get_locked_file_path(lock->lk); | |
2507 | int res = unlink_or_msg(loose_filename, err); | |
2508 | free(loose_filename); | |
2509 | if (res) | |
2510 | return 1; | |
2511 | } | |
2512 | return 0; | |
2513 | } | |
2514 | ||
2515 | int delete_refs(struct string_list *refnames, unsigned int flags) | |
2516 | { | |
2517 | struct strbuf err = STRBUF_INIT; | |
2518 | int i, result = 0; | |
2519 | ||
2520 | if (!refnames->nr) | |
2521 | return 0; | |
2522 | ||
2523 | result = repack_without_refs(refnames, &err); | |
2524 | if (result) { | |
2525 | /* | |
2526 | * If we failed to rewrite the packed-refs file, then | |
2527 | * it is unsafe to try to remove loose refs, because | |
2528 | * doing so might expose an obsolete packed value for | |
2529 | * a reference that might even point at an object that | |
2530 | * has been garbage collected. | |
2531 | */ | |
2532 | if (refnames->nr == 1) | |
2533 | error(_("could not delete reference %s: %s"), | |
2534 | refnames->items[0].string, err.buf); | |
2535 | else | |
2536 | error(_("could not delete references: %s"), err.buf); | |
2537 | ||
2538 | goto out; | |
2539 | } | |
2540 | ||
2541 | for (i = 0; i < refnames->nr; i++) { | |
2542 | const char *refname = refnames->items[i].string; | |
2543 | ||
2544 | if (delete_ref(refname, NULL, flags)) | |
2545 | result |= error(_("could not remove reference %s"), refname); | |
2546 | } | |
2547 | ||
2548 | out: | |
2549 | strbuf_release(&err); | |
2550 | return result; | |
2551 | } | |
2552 | ||
2553 | /* | |
2554 | * People using contrib's git-new-workdir have .git/logs/refs -> | |
2555 | * /some/other/path/.git/logs/refs, and that may live on another device. | |
2556 | * | |
2557 | * IOW, to avoid cross device rename errors, the temporary renamed log must | |
2558 | * live into logs/refs. | |
2559 | */ | |
2560 | #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log" | |
2561 | ||
2562 | static int rename_tmp_log(const char *newrefname) | |
2563 | { | |
2564 | int attempts_remaining = 4; | |
2565 | struct strbuf path = STRBUF_INIT; | |
2566 | int ret = -1; | |
2567 | ||
2568 | retry: | |
2569 | strbuf_reset(&path); | |
2570 | strbuf_git_path(&path, "logs/%s", newrefname); | |
2571 | switch (safe_create_leading_directories_const(path.buf)) { | |
2572 | case SCLD_OK: | |
2573 | break; /* success */ | |
2574 | case SCLD_VANISHED: | |
2575 | if (--attempts_remaining > 0) | |
2576 | goto retry; | |
2577 | /* fall through */ | |
2578 | default: | |
2579 | error("unable to create directory for %s", newrefname); | |
2580 | goto out; | |
2581 | } | |
2582 | ||
2583 | if (rename(git_path(TMP_RENAMED_LOG), path.buf)) { | |
2584 | if ((errno==EISDIR || errno==ENOTDIR) && --attempts_remaining > 0) { | |
2585 | /* | |
2586 | * rename(a, b) when b is an existing | |
2587 | * directory ought to result in ISDIR, but | |
2588 | * Solaris 5.8 gives ENOTDIR. Sheesh. | |
2589 | */ | |
2590 | if (remove_empty_directories(&path)) { | |
2591 | error("Directory not empty: logs/%s", newrefname); | |
2592 | goto out; | |
2593 | } | |
2594 | goto retry; | |
2595 | } else if (errno == ENOENT && --attempts_remaining > 0) { | |
2596 | /* | |
2597 | * Maybe another process just deleted one of | |
2598 | * the directories in the path to newrefname. | |
2599 | * Try again from the beginning. | |
2600 | */ | |
2601 | goto retry; | |
2602 | } else { | |
2603 | error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s", | |
2604 | newrefname, strerror(errno)); | |
2605 | goto out; | |
2606 | } | |
2607 | } | |
2608 | ret = 0; | |
2609 | out: | |
2610 | strbuf_release(&path); | |
2611 | return ret; | |
2612 | } | |
2613 | ||
2614 | int verify_refname_available(const char *newname, | |
2615 | const struct string_list *extras, | |
2616 | const struct string_list *skip, | |
2617 | struct strbuf *err) | |
2618 | { | |
2619 | struct ref_dir *packed_refs = get_packed_refs(&ref_store); | |
2620 | struct ref_dir *loose_refs = get_loose_refs(&ref_store); | |
2621 | ||
2622 | if (verify_refname_available_dir(newname, extras, skip, | |
2623 | packed_refs, err) || | |
2624 | verify_refname_available_dir(newname, extras, skip, | |
2625 | loose_refs, err)) | |
2626 | return -1; | |
2627 | ||
2628 | return 0; | |
2629 | } | |
2630 | ||
2631 | static int write_ref_to_lockfile(struct ref_lock *lock, | |
2632 | const unsigned char *sha1, struct strbuf *err); | |
2633 | static int commit_ref_update(struct ref_lock *lock, | |
2634 | const unsigned char *sha1, const char *logmsg, | |
2635 | struct strbuf *err); | |
2636 | ||
2637 | int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg) | |
2638 | { | |
2639 | unsigned char sha1[20], orig_sha1[20]; | |
2640 | int flag = 0, logmoved = 0; | |
2641 | struct ref_lock *lock; | |
2642 | struct stat loginfo; | |
2643 | int log = !lstat(git_path("logs/%s", oldrefname), &loginfo); | |
2644 | struct strbuf err = STRBUF_INIT; | |
2645 | ||
2646 | if (log && S_ISLNK(loginfo.st_mode)) | |
2647 | return error("reflog for %s is a symlink", oldrefname); | |
2648 | ||
2649 | if (!resolve_ref_unsafe(oldrefname, RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, | |
2650 | orig_sha1, &flag)) | |
2651 | return error("refname %s not found", oldrefname); | |
2652 | ||
2653 | if (flag & REF_ISSYMREF) | |
2654 | return error("refname %s is a symbolic ref, renaming it is not supported", | |
2655 | oldrefname); | |
2656 | if (!rename_ref_available(oldrefname, newrefname)) | |
2657 | return 1; | |
2658 | ||
2659 | if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG))) | |
2660 | return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s", | |
2661 | oldrefname, strerror(errno)); | |
2662 | ||
2663 | if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) { | |
2664 | error("unable to delete old %s", oldrefname); | |
2665 | goto rollback; | |
2666 | } | |
2667 | ||
2668 | /* | |
2669 | * Since we are doing a shallow lookup, sha1 is not the | |
2670 | * correct value to pass to delete_ref as old_sha1. But that | |
2671 | * doesn't matter, because an old_sha1 check wouldn't add to | |
2672 | * the safety anyway; we want to delete the reference whatever | |
2673 | * its current value. | |
2674 | */ | |
2675 | if (!read_ref_full(newrefname, RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, | |
2676 | sha1, NULL) && | |
2677 | delete_ref(newrefname, NULL, REF_NODEREF)) { | |
2678 | if (errno==EISDIR) { | |
2679 | struct strbuf path = STRBUF_INIT; | |
2680 | int result; | |
2681 | ||
2682 | strbuf_git_path(&path, "%s", newrefname); | |
2683 | result = remove_empty_directories(&path); | |
2684 | strbuf_release(&path); | |
2685 | ||
2686 | if (result) { | |
2687 | error("Directory not empty: %s", newrefname); | |
2688 | goto rollback; | |
2689 | } | |
2690 | } else { | |
2691 | error("unable to delete existing %s", newrefname); | |
2692 | goto rollback; | |
2693 | } | |
2694 | } | |
2695 | ||
2696 | if (log && rename_tmp_log(newrefname)) | |
2697 | goto rollback; | |
2698 | ||
2699 | logmoved = log; | |
2700 | ||
2701 | lock = lock_ref_sha1_basic(newrefname, NULL, NULL, NULL, REF_NODEREF, | |
2702 | NULL, &err); | |
2703 | if (!lock) { | |
2704 | error("unable to rename '%s' to '%s': %s", oldrefname, newrefname, err.buf); | |
2705 | strbuf_release(&err); | |
2706 | goto rollback; | |
2707 | } | |
2708 | hashcpy(lock->old_oid.hash, orig_sha1); | |
2709 | ||
2710 | if (write_ref_to_lockfile(lock, orig_sha1, &err) || | |
2711 | commit_ref_update(lock, orig_sha1, logmsg, &err)) { | |
2712 | error("unable to write current sha1 into %s: %s", newrefname, err.buf); | |
2713 | strbuf_release(&err); | |
2714 | goto rollback; | |
2715 | } | |
2716 | ||
2717 | return 0; | |
2718 | ||
2719 | rollback: | |
2720 | lock = lock_ref_sha1_basic(oldrefname, NULL, NULL, NULL, REF_NODEREF, | |
2721 | NULL, &err); | |
2722 | if (!lock) { | |
2723 | error("unable to lock %s for rollback: %s", oldrefname, err.buf); | |
2724 | strbuf_release(&err); | |
2725 | goto rollbacklog; | |
2726 | } | |
2727 | ||
2728 | flag = log_all_ref_updates; | |
2729 | log_all_ref_updates = 0; | |
2730 | if (write_ref_to_lockfile(lock, orig_sha1, &err) || | |
2731 | commit_ref_update(lock, orig_sha1, NULL, &err)) { | |
2732 | error("unable to write current sha1 into %s: %s", oldrefname, err.buf); | |
2733 | strbuf_release(&err); | |
2734 | } | |
2735 | log_all_ref_updates = flag; | |
2736 | ||
2737 | rollbacklog: | |
2738 | if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname))) | |
2739 | error("unable to restore logfile %s from %s: %s", | |
2740 | oldrefname, newrefname, strerror(errno)); | |
2741 | if (!logmoved && log && | |
2742 | rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname))) | |
2743 | error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s", | |
2744 | oldrefname, strerror(errno)); | |
2745 | ||
2746 | return 1; | |
2747 | } | |
2748 | ||
2749 | static int close_ref(struct ref_lock *lock) | |
2750 | { | |
2751 | if (close_lock_file(lock->lk)) | |
2752 | return -1; | |
2753 | return 0; | |
2754 | } | |
2755 | ||
2756 | static int commit_ref(struct ref_lock *lock) | |
2757 | { | |
2758 | char *path = get_locked_file_path(lock->lk); | |
2759 | struct stat st; | |
2760 | ||
2761 | if (!lstat(path, &st) && S_ISDIR(st.st_mode)) { | |
2762 | /* | |
2763 | * There is a directory at the path we want to rename | |
2764 | * the lockfile to. Hopefully it is empty; try to | |
2765 | * delete it. | |
2766 | */ | |
2767 | size_t len = strlen(path); | |
2768 | struct strbuf sb_path = STRBUF_INIT; | |
2769 | ||
2770 | strbuf_attach(&sb_path, path, len, len); | |
2771 | ||
2772 | /* | |
2773 | * If this fails, commit_lock_file() will also fail | |
2774 | * and will report the problem. | |
2775 | */ | |
2776 | remove_empty_directories(&sb_path); | |
2777 | strbuf_release(&sb_path); | |
2778 | } else { | |
2779 | free(path); | |
2780 | } | |
2781 | ||
2782 | if (commit_lock_file(lock->lk)) | |
2783 | return -1; | |
2784 | return 0; | |
2785 | } | |
2786 | ||
2787 | /* | |
2788 | * Create a reflog for a ref. If force_create = 0, the reflog will | |
2789 | * only be created for certain refs (those for which | |
2790 | * should_autocreate_reflog returns non-zero. Otherwise, create it | |
2791 | * regardless of the ref name. Fill in *err and return -1 on failure. | |
2792 | */ | |
2793 | static int log_ref_setup(const char *refname, struct strbuf *logfile, struct strbuf *err, int force_create) | |
2794 | { | |
2795 | int logfd, oflags = O_APPEND | O_WRONLY; | |
2796 | ||
2797 | strbuf_git_path(logfile, "logs/%s", refname); | |
2798 | if (force_create || should_autocreate_reflog(refname)) { | |
2799 | if (safe_create_leading_directories(logfile->buf) < 0) { | |
2800 | strbuf_addf(err, "unable to create directory for '%s': " | |
2801 | "%s", logfile->buf, strerror(errno)); | |
2802 | return -1; | |
2803 | } | |
2804 | oflags |= O_CREAT; | |
2805 | } | |
2806 | ||
2807 | logfd = open(logfile->buf, oflags, 0666); | |
2808 | if (logfd < 0) { | |
2809 | if (!(oflags & O_CREAT) && (errno == ENOENT || errno == EISDIR)) | |
2810 | return 0; | |
2811 | ||
2812 | if (errno == EISDIR) { | |
2813 | if (remove_empty_directories(logfile)) { | |
2814 | strbuf_addf(err, "there are still logs under " | |
2815 | "'%s'", logfile->buf); | |
2816 | return -1; | |
2817 | } | |
2818 | logfd = open(logfile->buf, oflags, 0666); | |
2819 | } | |
2820 | ||
2821 | if (logfd < 0) { | |
2822 | strbuf_addf(err, "unable to append to '%s': %s", | |
2823 | logfile->buf, strerror(errno)); | |
2824 | return -1; | |
2825 | } | |
2826 | } | |
2827 | ||
2828 | adjust_shared_perm(logfile->buf); | |
2829 | close(logfd); | |
2830 | return 0; | |
2831 | } | |
2832 | ||
2833 | ||
2834 | int safe_create_reflog(const char *refname, int force_create, struct strbuf *err) | |
2835 | { | |
2836 | int ret; | |
2837 | struct strbuf sb = STRBUF_INIT; | |
2838 | ||
2839 | ret = log_ref_setup(refname, &sb, err, force_create); | |
2840 | strbuf_release(&sb); | |
2841 | return ret; | |
2842 | } | |
2843 | ||
2844 | static int log_ref_write_fd(int fd, const unsigned char *old_sha1, | |
2845 | const unsigned char *new_sha1, | |
2846 | const char *committer, const char *msg) | |
2847 | { | |
2848 | int msglen, written; | |
2849 | unsigned maxlen, len; | |
2850 | char *logrec; | |
2851 | ||
2852 | msglen = msg ? strlen(msg) : 0; | |
2853 | maxlen = strlen(committer) + msglen + 100; | |
2854 | logrec = xmalloc(maxlen); | |
2855 | len = xsnprintf(logrec, maxlen, "%s %s %s\n", | |
2856 | sha1_to_hex(old_sha1), | |
2857 | sha1_to_hex(new_sha1), | |
2858 | committer); | |
2859 | if (msglen) | |
2860 | len += copy_reflog_msg(logrec + len - 1, msg) - 1; | |
2861 | ||
2862 | written = len <= maxlen ? write_in_full(fd, logrec, len) : -1; | |
2863 | free(logrec); | |
2864 | if (written != len) | |
2865 | return -1; | |
2866 | ||
2867 | return 0; | |
2868 | } | |
2869 | ||
2870 | static int log_ref_write_1(const char *refname, const unsigned char *old_sha1, | |
2871 | const unsigned char *new_sha1, const char *msg, | |
2872 | struct strbuf *logfile, int flags, | |
2873 | struct strbuf *err) | |
2874 | { | |
2875 | int logfd, result, oflags = O_APPEND | O_WRONLY; | |
2876 | ||
2877 | if (log_all_ref_updates < 0) | |
2878 | log_all_ref_updates = !is_bare_repository(); | |
2879 | ||
2880 | result = log_ref_setup(refname, logfile, err, flags & REF_FORCE_CREATE_REFLOG); | |
2881 | ||
2882 | if (result) | |
2883 | return result; | |
2884 | ||
2885 | logfd = open(logfile->buf, oflags); | |
2886 | if (logfd < 0) | |
2887 | return 0; | |
2888 | result = log_ref_write_fd(logfd, old_sha1, new_sha1, | |
2889 | git_committer_info(0), msg); | |
2890 | if (result) { | |
2891 | strbuf_addf(err, "unable to append to '%s': %s", logfile->buf, | |
2892 | strerror(errno)); | |
2893 | close(logfd); | |
2894 | return -1; | |
2895 | } | |
2896 | if (close(logfd)) { | |
2897 | strbuf_addf(err, "unable to append to '%s': %s", logfile->buf, | |
2898 | strerror(errno)); | |
2899 | return -1; | |
2900 | } | |
2901 | return 0; | |
2902 | } | |
2903 | ||
2904 | static int log_ref_write(const char *refname, const unsigned char *old_sha1, | |
2905 | const unsigned char *new_sha1, const char *msg, | |
2906 | int flags, struct strbuf *err) | |
2907 | { | |
2908 | return files_log_ref_write(refname, old_sha1, new_sha1, msg, flags, | |
2909 | err); | |
2910 | } | |
2911 | ||
2912 | int files_log_ref_write(const char *refname, const unsigned char *old_sha1, | |
2913 | const unsigned char *new_sha1, const char *msg, | |
2914 | int flags, struct strbuf *err) | |
2915 | { | |
2916 | struct strbuf sb = STRBUF_INIT; | |
2917 | int ret = log_ref_write_1(refname, old_sha1, new_sha1, msg, &sb, flags, | |
2918 | err); | |
2919 | strbuf_release(&sb); | |
2920 | return ret; | |
2921 | } | |
2922 | ||
2923 | /* | |
2924 | * Write sha1 into the open lockfile, then close the lockfile. On | |
2925 | * errors, rollback the lockfile, fill in *err and | |
2926 | * return -1. | |
2927 | */ | |
2928 | static int write_ref_to_lockfile(struct ref_lock *lock, | |
2929 | const unsigned char *sha1, struct strbuf *err) | |
2930 | { | |
2931 | static char term = '\n'; | |
2932 | struct object *o; | |
2933 | int fd; | |
2934 | ||
2935 | o = parse_object(sha1); | |
2936 | if (!o) { | |
2937 | strbuf_addf(err, | |
2938 | "trying to write ref '%s' with nonexistent object %s", | |
2939 | lock->ref_name, sha1_to_hex(sha1)); | |
2940 | unlock_ref(lock); | |
2941 | return -1; | |
2942 | } | |
2943 | if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) { | |
2944 | strbuf_addf(err, | |
2945 | "trying to write non-commit object %s to branch '%s'", | |
2946 | sha1_to_hex(sha1), lock->ref_name); | |
2947 | unlock_ref(lock); | |
2948 | return -1; | |
2949 | } | |
2950 | fd = get_lock_file_fd(lock->lk); | |
2951 | if (write_in_full(fd, sha1_to_hex(sha1), 40) != 40 || | |
2952 | write_in_full(fd, &term, 1) != 1 || | |
2953 | close_ref(lock) < 0) { | |
2954 | strbuf_addf(err, | |
2955 | "couldn't write '%s'", get_lock_file_path(lock->lk)); | |
2956 | unlock_ref(lock); | |
2957 | return -1; | |
2958 | } | |
2959 | return 0; | |
2960 | } | |
2961 | ||
2962 | /* | |
2963 | * Commit a change to a loose reference that has already been written | |
2964 | * to the loose reference lockfile. Also update the reflogs if | |
2965 | * necessary, using the specified lockmsg (which can be NULL). | |
2966 | */ | |
2967 | static int commit_ref_update(struct ref_lock *lock, | |
2968 | const unsigned char *sha1, const char *logmsg, | |
2969 | struct strbuf *err) | |
2970 | { | |
2971 | clear_loose_ref_cache(&ref_store); | |
2972 | if (log_ref_write(lock->ref_name, lock->old_oid.hash, sha1, logmsg, 0, err)) { | |
2973 | char *old_msg = strbuf_detach(err, NULL); | |
2974 | strbuf_addf(err, "cannot update the ref '%s': %s", | |
2975 | lock->ref_name, old_msg); | |
2976 | free(old_msg); | |
2977 | unlock_ref(lock); | |
2978 | return -1; | |
2979 | } | |
2980 | ||
2981 | if (strcmp(lock->ref_name, "HEAD") != 0) { | |
2982 | /* | |
2983 | * Special hack: If a branch is updated directly and HEAD | |
2984 | * points to it (may happen on the remote side of a push | |
2985 | * for example) then logically the HEAD reflog should be | |
2986 | * updated too. | |
2987 | * A generic solution implies reverse symref information, | |
2988 | * but finding all symrefs pointing to the given branch | |
2989 | * would be rather costly for this rare event (the direct | |
2990 | * update of a branch) to be worth it. So let's cheat and | |
2991 | * check with HEAD only which should cover 99% of all usage | |
2992 | * scenarios (even 100% of the default ones). | |
2993 | */ | |
2994 | unsigned char head_sha1[20]; | |
2995 | int head_flag; | |
2996 | const char *head_ref; | |
2997 | ||
2998 | head_ref = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, | |
2999 | head_sha1, &head_flag); | |
3000 | if (head_ref && (head_flag & REF_ISSYMREF) && | |
3001 | !strcmp(head_ref, lock->ref_name)) { | |
3002 | struct strbuf log_err = STRBUF_INIT; | |
3003 | if (log_ref_write("HEAD", lock->old_oid.hash, sha1, | |
3004 | logmsg, 0, &log_err)) { | |
3005 | error("%s", log_err.buf); | |
3006 | strbuf_release(&log_err); | |
3007 | } | |
3008 | } | |
3009 | } | |
3010 | ||
3011 | if (commit_ref(lock)) { | |
3012 | strbuf_addf(err, "couldn't set '%s'", lock->ref_name); | |
3013 | unlock_ref(lock); | |
3014 | return -1; | |
3015 | } | |
3016 | ||
3017 | unlock_ref(lock); | |
3018 | return 0; | |
3019 | } | |
3020 | ||
3021 | static int create_ref_symlink(struct ref_lock *lock, const char *target) | |
3022 | { | |
3023 | int ret = -1; | |
3024 | #ifndef NO_SYMLINK_HEAD | |
3025 | char *ref_path = get_locked_file_path(lock->lk); | |
3026 | unlink(ref_path); | |
3027 | ret = symlink(target, ref_path); | |
3028 | free(ref_path); | |
3029 | ||
3030 | if (ret) | |
3031 | fprintf(stderr, "no symlink - falling back to symbolic ref\n"); | |
3032 | #endif | |
3033 | return ret; | |
3034 | } | |
3035 | ||
3036 | static void update_symref_reflog(struct ref_lock *lock, const char *refname, | |
3037 | const char *target, const char *logmsg) | |
3038 | { | |
3039 | struct strbuf err = STRBUF_INIT; | |
3040 | unsigned char new_sha1[20]; | |
3041 | if (logmsg && !read_ref(target, new_sha1) && | |
3042 | log_ref_write(refname, lock->old_oid.hash, new_sha1, logmsg, 0, &err)) { | |
3043 | error("%s", err.buf); | |
3044 | strbuf_release(&err); | |
3045 | } | |
3046 | } | |
3047 | ||
3048 | static int create_symref_locked(struct ref_lock *lock, const char *refname, | |
3049 | const char *target, const char *logmsg) | |
3050 | { | |
3051 | if (prefer_symlink_refs && !create_ref_symlink(lock, target)) { | |
3052 | update_symref_reflog(lock, refname, target, logmsg); | |
3053 | return 0; | |
3054 | } | |
3055 | ||
3056 | if (!fdopen_lock_file(lock->lk, "w")) | |
3057 | return error("unable to fdopen %s: %s", | |
3058 | lock->lk->tempfile.filename.buf, strerror(errno)); | |
3059 | ||
3060 | update_symref_reflog(lock, refname, target, logmsg); | |
3061 | ||
3062 | /* no error check; commit_ref will check ferror */ | |
3063 | fprintf(lock->lk->tempfile.fp, "ref: %s\n", target); | |
3064 | if (commit_ref(lock) < 0) | |
3065 | return error("unable to write symref for %s: %s", refname, | |
3066 | strerror(errno)); | |
3067 | return 0; | |
3068 | } | |
3069 | ||
3070 | int create_symref(const char *refname, const char *target, const char *logmsg) | |
3071 | { | |
3072 | struct strbuf err = STRBUF_INIT; | |
3073 | struct ref_lock *lock; | |
3074 | int ret; | |
3075 | ||
3076 | lock = lock_ref_sha1_basic(refname, NULL, NULL, NULL, REF_NODEREF, NULL, | |
3077 | &err); | |
3078 | if (!lock) { | |
3079 | error("%s", err.buf); | |
3080 | strbuf_release(&err); | |
3081 | return -1; | |
3082 | } | |
3083 | ||
3084 | ret = create_symref_locked(lock, refname, target, logmsg); | |
3085 | unlock_ref(lock); | |
3086 | return ret; | |
3087 | } | |
3088 | ||
3089 | int set_worktree_head_symref(const char *gitdir, const char *target) | |
3090 | { | |
3091 | static struct lock_file head_lock; | |
3092 | struct ref_lock *lock; | |
3093 | struct strbuf head_path = STRBUF_INIT; | |
3094 | const char *head_rel; | |
3095 | int ret; | |
3096 | ||
3097 | strbuf_addf(&head_path, "%s/HEAD", absolute_path(gitdir)); | |
3098 | if (hold_lock_file_for_update(&head_lock, head_path.buf, | |
3099 | LOCK_NO_DEREF) < 0) { | |
3100 | struct strbuf err = STRBUF_INIT; | |
3101 | unable_to_lock_message(head_path.buf, errno, &err); | |
3102 | error("%s", err.buf); | |
3103 | strbuf_release(&err); | |
3104 | strbuf_release(&head_path); | |
3105 | return -1; | |
3106 | } | |
3107 | ||
3108 | /* head_rel will be "HEAD" for the main tree, "worktrees/wt/HEAD" for | |
3109 | linked trees */ | |
3110 | head_rel = remove_leading_path(head_path.buf, | |
3111 | absolute_path(get_git_common_dir())); | |
3112 | /* to make use of create_symref_locked(), initialize ref_lock */ | |
3113 | lock = xcalloc(1, sizeof(struct ref_lock)); | |
3114 | lock->lk = &head_lock; | |
3115 | lock->ref_name = xstrdup(head_rel); | |
3116 | ||
3117 | ret = create_symref_locked(lock, head_rel, target, NULL); | |
3118 | ||
3119 | unlock_ref(lock); /* will free lock */ | |
3120 | strbuf_release(&head_path); | |
3121 | return ret; | |
3122 | } | |
3123 | ||
3124 | int reflog_exists(const char *refname) | |
3125 | { | |
3126 | struct stat st; | |
3127 | ||
3128 | return !lstat(git_path("logs/%s", refname), &st) && | |
3129 | S_ISREG(st.st_mode); | |
3130 | } | |
3131 | ||
3132 | int delete_reflog(const char *refname) | |
3133 | { | |
3134 | return remove_path(git_path("logs/%s", refname)); | |
3135 | } | |
3136 | ||
3137 | static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data) | |
3138 | { | |
3139 | unsigned char osha1[20], nsha1[20]; | |
3140 | char *email_end, *message; | |
3141 | unsigned long timestamp; | |
3142 | int tz; | |
3143 | ||
3144 | /* old SP new SP name <email> SP time TAB msg LF */ | |
3145 | if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' || | |
3146 | get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' || | |
3147 | get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' || | |
3148 | !(email_end = strchr(sb->buf + 82, '>')) || | |
3149 | email_end[1] != ' ' || | |
3150 | !(timestamp = strtoul(email_end + 2, &message, 10)) || | |
3151 | !message || message[0] != ' ' || | |
3152 | (message[1] != '+' && message[1] != '-') || | |
3153 | !isdigit(message[2]) || !isdigit(message[3]) || | |
3154 | !isdigit(message[4]) || !isdigit(message[5])) | |
3155 | return 0; /* corrupt? */ | |
3156 | email_end[1] = '\0'; | |
3157 | tz = strtol(message + 1, NULL, 10); | |
3158 | if (message[6] != '\t') | |
3159 | message += 6; | |
3160 | else | |
3161 | message += 7; | |
3162 | return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data); | |
3163 | } | |
3164 | ||
3165 | static char *find_beginning_of_line(char *bob, char *scan) | |
3166 | { | |
3167 | while (bob < scan && *(--scan) != '\n') | |
3168 | ; /* keep scanning backwards */ | |
3169 | /* | |
3170 | * Return either beginning of the buffer, or LF at the end of | |
3171 | * the previous line. | |
3172 | */ | |
3173 | return scan; | |
3174 | } | |
3175 | ||
3176 | int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data) | |
3177 | { | |
3178 | struct strbuf sb = STRBUF_INIT; | |
3179 | FILE *logfp; | |
3180 | long pos; | |
3181 | int ret = 0, at_tail = 1; | |
3182 | ||
3183 | logfp = fopen(git_path("logs/%s", refname), "r"); | |
3184 | if (!logfp) | |
3185 | return -1; | |
3186 | ||
3187 | /* Jump to the end */ | |
3188 | if (fseek(logfp, 0, SEEK_END) < 0) | |
3189 | return error("cannot seek back reflog for %s: %s", | |
3190 | refname, strerror(errno)); | |
3191 | pos = ftell(logfp); | |
3192 | while (!ret && 0 < pos) { | |
3193 | int cnt; | |
3194 | size_t nread; | |
3195 | char buf[BUFSIZ]; | |
3196 | char *endp, *scanp; | |
3197 | ||
3198 | /* Fill next block from the end */ | |
3199 | cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos; | |
3200 | if (fseek(logfp, pos - cnt, SEEK_SET)) | |
3201 | return error("cannot seek back reflog for %s: %s", | |
3202 | refname, strerror(errno)); | |
3203 | nread = fread(buf, cnt, 1, logfp); | |
3204 | if (nread != 1) | |
3205 | return error("cannot read %d bytes from reflog for %s: %s", | |
3206 | cnt, refname, strerror(errno)); | |
3207 | pos -= cnt; | |
3208 | ||
3209 | scanp = endp = buf + cnt; | |
3210 | if (at_tail && scanp[-1] == '\n') | |
3211 | /* Looking at the final LF at the end of the file */ | |
3212 | scanp--; | |
3213 | at_tail = 0; | |
3214 | ||
3215 | while (buf < scanp) { | |
3216 | /* | |
3217 | * terminating LF of the previous line, or the beginning | |
3218 | * of the buffer. | |
3219 | */ | |
3220 | char *bp; | |
3221 | ||
3222 | bp = find_beginning_of_line(buf, scanp); | |
3223 | ||
3224 | if (*bp == '\n') { | |
3225 | /* | |
3226 | * The newline is the end of the previous line, | |
3227 | * so we know we have complete line starting | |
3228 | * at (bp + 1). Prefix it onto any prior data | |
3229 | * we collected for the line and process it. | |
3230 | */ | |
3231 | strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1)); | |
3232 | scanp = bp; | |
3233 | endp = bp + 1; | |
3234 | ret = show_one_reflog_ent(&sb, fn, cb_data); | |
3235 | strbuf_reset(&sb); | |
3236 | if (ret) | |
3237 | break; | |
3238 | } else if (!pos) { | |
3239 | /* | |
3240 | * We are at the start of the buffer, and the | |
3241 | * start of the file; there is no previous | |
3242 | * line, and we have everything for this one. | |
3243 | * Process it, and we can end the loop. | |
3244 | */ | |
3245 | strbuf_splice(&sb, 0, 0, buf, endp - buf); | |
3246 | ret = show_one_reflog_ent(&sb, fn, cb_data); | |
3247 | strbuf_reset(&sb); | |
3248 | break; | |
3249 | } | |
3250 | ||
3251 | if (bp == buf) { | |
3252 | /* | |
3253 | * We are at the start of the buffer, and there | |
3254 | * is more file to read backwards. Which means | |
3255 | * we are in the middle of a line. Note that we | |
3256 | * may get here even if *bp was a newline; that | |
3257 | * just means we are at the exact end of the | |
3258 | * previous line, rather than some spot in the | |
3259 | * middle. | |
3260 | * | |
3261 | * Save away what we have to be combined with | |
3262 | * the data from the next read. | |
3263 | */ | |
3264 | strbuf_splice(&sb, 0, 0, buf, endp - buf); | |
3265 | break; | |
3266 | } | |
3267 | } | |
3268 | ||
3269 | } | |
3270 | if (!ret && sb.len) | |
3271 | die("BUG: reverse reflog parser had leftover data"); | |
3272 | ||
3273 | fclose(logfp); | |
3274 | strbuf_release(&sb); | |
3275 | return ret; | |
3276 | } | |
3277 | ||
3278 | int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data) | |
3279 | { | |
3280 | FILE *logfp; | |
3281 | struct strbuf sb = STRBUF_INIT; | |
3282 | int ret = 0; | |
3283 | ||
3284 | logfp = fopen(git_path("logs/%s", refname), "r"); | |
3285 | if (!logfp) | |
3286 | return -1; | |
3287 | ||
3288 | while (!ret && !strbuf_getwholeline(&sb, logfp, '\n')) | |
3289 | ret = show_one_reflog_ent(&sb, fn, cb_data); | |
3290 | fclose(logfp); | |
3291 | strbuf_release(&sb); | |
3292 | return ret; | |
3293 | } | |
3294 | ||
3295 | struct files_reflog_iterator { | |
3296 | struct ref_iterator base; | |
3297 | ||
3298 | struct dir_iterator *dir_iterator; | |
3299 | struct object_id oid; | |
3300 | }; | |
3301 | ||
3302 | static int files_reflog_iterator_advance(struct ref_iterator *ref_iterator) | |
3303 | { | |
3304 | struct files_reflog_iterator *iter = | |
3305 | (struct files_reflog_iterator *)ref_iterator; | |
3306 | struct dir_iterator *diter = iter->dir_iterator; | |
3307 | int ok; | |
3308 | ||
3309 | while ((ok = dir_iterator_advance(diter)) == ITER_OK) { | |
3310 | int flags; | |
3311 | ||
3312 | if (!S_ISREG(diter->st.st_mode)) | |
3313 | continue; | |
3314 | if (diter->basename[0] == '.') | |
3315 | continue; | |
3316 | if (ends_with(diter->basename, ".lock")) | |
3317 | continue; | |
3318 | ||
3319 | if (read_ref_full(diter->relative_path, 0, | |
3320 | iter->oid.hash, &flags)) { | |
3321 | error("bad ref for %s", diter->path.buf); | |
3322 | continue; | |
3323 | } | |
3324 | ||
3325 | iter->base.refname = diter->relative_path; | |
3326 | iter->base.oid = &iter->oid; | |
3327 | iter->base.flags = flags; | |
3328 | return ITER_OK; | |
3329 | } | |
3330 | ||
3331 | iter->dir_iterator = NULL; | |
3332 | if (ref_iterator_abort(ref_iterator) == ITER_ERROR) | |
3333 | ok = ITER_ERROR; | |
3334 | return ok; | |
3335 | } | |
3336 | ||
3337 | static int files_reflog_iterator_peel(struct ref_iterator *ref_iterator, | |
3338 | struct object_id *peeled) | |
3339 | { | |
3340 | die("BUG: ref_iterator_peel() called for reflog_iterator"); | |
3341 | } | |
3342 | ||
3343 | static int files_reflog_iterator_abort(struct ref_iterator *ref_iterator) | |
3344 | { | |
3345 | struct files_reflog_iterator *iter = | |
3346 | (struct files_reflog_iterator *)ref_iterator; | |
3347 | int ok = ITER_DONE; | |
3348 | ||
3349 | if (iter->dir_iterator) | |
3350 | ok = dir_iterator_abort(iter->dir_iterator); | |
3351 | ||
3352 | base_ref_iterator_free(ref_iterator); | |
3353 | return ok; | |
3354 | } | |
3355 | ||
3356 | static struct ref_iterator_vtable files_reflog_iterator_vtable = { | |
3357 | files_reflog_iterator_advance, | |
3358 | files_reflog_iterator_peel, | |
3359 | files_reflog_iterator_abort | |
3360 | }; | |
3361 | ||
3362 | struct ref_iterator *files_reflog_iterator_begin(void) | |
3363 | { | |
3364 | struct files_reflog_iterator *iter = xcalloc(1, sizeof(*iter)); | |
3365 | struct ref_iterator *ref_iterator = &iter->base; | |
3366 | ||
3367 | base_ref_iterator_init(ref_iterator, &files_reflog_iterator_vtable); | |
3368 | iter->dir_iterator = dir_iterator_begin(git_path("logs")); | |
3369 | return ref_iterator; | |
3370 | } | |
3371 | ||
3372 | int for_each_reflog(each_ref_fn fn, void *cb_data) | |
3373 | { | |
3374 | return do_for_each_ref_iterator(files_reflog_iterator_begin(), | |
3375 | fn, cb_data); | |
3376 | } | |
3377 | ||
3378 | static int ref_update_reject_duplicates(struct string_list *refnames, | |
3379 | struct strbuf *err) | |
3380 | { | |
3381 | int i, n = refnames->nr; | |
3382 | ||
3383 | assert(err); | |
3384 | ||
3385 | for (i = 1; i < n; i++) | |
3386 | if (!strcmp(refnames->items[i - 1].string, refnames->items[i].string)) { | |
3387 | strbuf_addf(err, | |
3388 | "multiple updates for ref '%s' not allowed.", | |
3389 | refnames->items[i].string); | |
3390 | return 1; | |
3391 | } | |
3392 | return 0; | |
3393 | } | |
3394 | ||
3395 | /* | |
3396 | * If update is a direct update of head_ref (the reference pointed to | |
3397 | * by HEAD), then add an extra REF_LOG_ONLY update for HEAD. | |
3398 | */ | |
3399 | static int split_head_update(struct ref_update *update, | |
3400 | struct ref_transaction *transaction, | |
3401 | const char *head_ref, | |
3402 | struct string_list *affected_refnames, | |
3403 | struct strbuf *err) | |
3404 | { | |
3405 | struct string_list_item *item; | |
3406 | struct ref_update *new_update; | |
3407 | ||
3408 | if ((update->flags & REF_LOG_ONLY) || | |
3409 | (update->flags & REF_ISPRUNING) || | |
3410 | (update->flags & REF_UPDATE_VIA_HEAD)) | |
3411 | return 0; | |
3412 | ||
3413 | if (strcmp(update->refname, head_ref)) | |
3414 | return 0; | |
3415 | ||
3416 | /* | |
3417 | * First make sure that HEAD is not already in the | |
3418 | * transaction. This insertion is O(N) in the transaction | |
3419 | * size, but it happens at most once per transaction. | |
3420 | */ | |
3421 | item = string_list_insert(affected_refnames, "HEAD"); | |
3422 | if (item->util) { | |
3423 | /* An entry already existed */ | |
3424 | strbuf_addf(err, | |
3425 | "multiple updates for 'HEAD' (including one " | |
3426 | "via its referent '%s') are not allowed", | |
3427 | update->refname); | |
3428 | return TRANSACTION_NAME_CONFLICT; | |
3429 | } | |
3430 | ||
3431 | new_update = ref_transaction_add_update( | |
3432 | transaction, "HEAD", | |
3433 | update->flags | REF_LOG_ONLY | REF_NODEREF, | |
3434 | update->new_sha1, update->old_sha1, | |
3435 | update->msg); | |
3436 | ||
3437 | item->util = new_update; | |
3438 | ||
3439 | return 0; | |
3440 | } | |
3441 | ||
3442 | /* | |
3443 | * update is for a symref that points at referent and doesn't have | |
3444 | * REF_NODEREF set. Split it into two updates: | |
3445 | * - The original update, but with REF_LOG_ONLY and REF_NODEREF set | |
3446 | * - A new, separate update for the referent reference | |
3447 | * Note that the new update will itself be subject to splitting when | |
3448 | * the iteration gets to it. | |
3449 | */ | |
3450 | static int split_symref_update(struct ref_update *update, | |
3451 | const char *referent, | |
3452 | struct ref_transaction *transaction, | |
3453 | struct string_list *affected_refnames, | |
3454 | struct strbuf *err) | |
3455 | { | |
3456 | struct string_list_item *item; | |
3457 | struct ref_update *new_update; | |
3458 | unsigned int new_flags; | |
3459 | ||
3460 | /* | |
3461 | * First make sure that referent is not already in the | |
3462 | * transaction. This insertion is O(N) in the transaction | |
3463 | * size, but it happens at most once per symref in a | |
3464 | * transaction. | |
3465 | */ | |
3466 | item = string_list_insert(affected_refnames, referent); | |
3467 | if (item->util) { | |
3468 | /* An entry already existed */ | |
3469 | strbuf_addf(err, | |
3470 | "multiple updates for '%s' (including one " | |
3471 | "via symref '%s') are not allowed", | |
3472 | referent, update->refname); | |
3473 | return TRANSACTION_NAME_CONFLICT; | |
3474 | } | |
3475 | ||
3476 | new_flags = update->flags; | |
3477 | if (!strcmp(update->refname, "HEAD")) { | |
3478 | /* | |
3479 | * Record that the new update came via HEAD, so that | |
3480 | * when we process it, split_head_update() doesn't try | |
3481 | * to add another reflog update for HEAD. Note that | |
3482 | * this bit will be propagated if the new_update | |
3483 | * itself needs to be split. | |
3484 | */ | |
3485 | new_flags |= REF_UPDATE_VIA_HEAD; | |
3486 | } | |
3487 | ||
3488 | new_update = ref_transaction_add_update( | |
3489 | transaction, referent, new_flags, | |
3490 | update->new_sha1, update->old_sha1, | |
3491 | update->msg); | |
3492 | ||
3493 | new_update->parent_update = update; | |
3494 | ||
3495 | /* | |
3496 | * Change the symbolic ref update to log only. Also, it | |
3497 | * doesn't need to check its old SHA-1 value, as that will be | |
3498 | * done when new_update is processed. | |
3499 | */ | |
3500 | update->flags |= REF_LOG_ONLY | REF_NODEREF; | |
3501 | update->flags &= ~REF_HAVE_OLD; | |
3502 | ||
3503 | item->util = new_update; | |
3504 | ||
3505 | return 0; | |
3506 | } | |
3507 | ||
3508 | /* | |
3509 | * Return the refname under which update was originally requested. | |
3510 | */ | |
3511 | static const char *original_update_refname(struct ref_update *update) | |
3512 | { | |
3513 | while (update->parent_update) | |
3514 | update = update->parent_update; | |
3515 | ||
3516 | return update->refname; | |
3517 | } | |
3518 | ||
3519 | /* | |
3520 | * Prepare for carrying out update: | |
3521 | * - Lock the reference referred to by update. | |
3522 | * - Read the reference under lock. | |
3523 | * - Check that its old SHA-1 value (if specified) is correct, and in | |
3524 | * any case record it in update->lock->old_oid for later use when | |
3525 | * writing the reflog. | |
3526 | * - If it is a symref update without REF_NODEREF, split it up into a | |
3527 | * REF_LOG_ONLY update of the symref and add a separate update for | |
3528 | * the referent to transaction. | |
3529 | * - If it is an update of head_ref, add a corresponding REF_LOG_ONLY | |
3530 | * update of HEAD. | |
3531 | */ | |
3532 | static int lock_ref_for_update(struct ref_update *update, | |
3533 | struct ref_transaction *transaction, | |
3534 | const char *head_ref, | |
3535 | struct string_list *affected_refnames, | |
3536 | struct strbuf *err) | |
3537 | { | |
3538 | struct strbuf referent = STRBUF_INIT; | |
3539 | int mustexist = (update->flags & REF_HAVE_OLD) && | |
3540 | !is_null_sha1(update->old_sha1); | |
3541 | int ret; | |
3542 | struct ref_lock *lock; | |
3543 | ||
3544 | if ((update->flags & REF_HAVE_NEW) && is_null_sha1(update->new_sha1)) | |
3545 | update->flags |= REF_DELETING; | |
3546 | ||
3547 | if (head_ref) { | |
3548 | ret = split_head_update(update, transaction, head_ref, | |
3549 | affected_refnames, err); | |
3550 | if (ret) | |
3551 | return ret; | |
3552 | } | |
3553 | ||
3554 | ret = lock_raw_ref(update->refname, mustexist, | |
3555 | affected_refnames, NULL, | |
3556 | &update->lock, &referent, | |
3557 | &update->type, err); | |
3558 | ||
3559 | if (ret) { | |
3560 | char *reason; | |
3561 | ||
3562 | reason = strbuf_detach(err, NULL); | |
3563 | strbuf_addf(err, "cannot lock ref '%s': %s", | |
3564 | update->refname, reason); | |
3565 | free(reason); | |
3566 | return ret; | |
3567 | } | |
3568 | ||
3569 | lock = update->lock; | |
3570 | ||
3571 | if (update->type & REF_ISSYMREF) { | |
3572 | if (update->flags & REF_NODEREF) { | |
3573 | /* | |
3574 | * We won't be reading the referent as part of | |
3575 | * the transaction, so we have to read it here | |
3576 | * to record and possibly check old_sha1: | |
3577 | */ | |
3578 | if (read_ref_full(update->refname, | |
3579 | mustexist ? RESOLVE_REF_READING : 0, | |
3580 | lock->old_oid.hash, NULL)) { | |
3581 | if (update->flags & REF_HAVE_OLD) { | |
3582 | strbuf_addf(err, "cannot lock ref '%s': " | |
3583 | "can't resolve old value", | |
3584 | update->refname); | |
3585 | return TRANSACTION_GENERIC_ERROR; | |
3586 | } else { | |
3587 | hashclr(lock->old_oid.hash); | |
3588 | } | |
3589 | } | |
3590 | if ((update->flags & REF_HAVE_OLD) && | |
3591 | hashcmp(lock->old_oid.hash, update->old_sha1)) { | |
3592 | strbuf_addf(err, "cannot lock ref '%s': " | |
3593 | "is at %s but expected %s", | |
3594 | update->refname, | |
3595 | sha1_to_hex(lock->old_oid.hash), | |
3596 | sha1_to_hex(update->old_sha1)); | |
3597 | return TRANSACTION_GENERIC_ERROR; | |
3598 | } | |
3599 | ||
3600 | } else { | |
3601 | /* | |
3602 | * Create a new update for the reference this | |
3603 | * symref is pointing at. Also, we will record | |
3604 | * and verify old_sha1 for this update as part | |
3605 | * of processing the split-off update, so we | |
3606 | * don't have to do it here. | |
3607 | */ | |
3608 | ret = split_symref_update(update, referent.buf, transaction, | |
3609 | affected_refnames, err); | |
3610 | if (ret) | |
3611 | return ret; | |
3612 | } | |
3613 | } else { | |
3614 | struct ref_update *parent_update; | |
3615 | ||
3616 | /* | |
3617 | * If this update is happening indirectly because of a | |
3618 | * symref update, record the old SHA-1 in the parent | |
3619 | * update: | |
3620 | */ | |
3621 | for (parent_update = update->parent_update; | |
3622 | parent_update; | |
3623 | parent_update = parent_update->parent_update) { | |
3624 | oidcpy(&parent_update->lock->old_oid, &lock->old_oid); | |
3625 | } | |
3626 | ||
3627 | if ((update->flags & REF_HAVE_OLD) && | |
3628 | hashcmp(lock->old_oid.hash, update->old_sha1)) { | |
3629 | if (is_null_sha1(update->old_sha1)) | |
3630 | strbuf_addf(err, "cannot lock ref '%s': reference already exists", | |
3631 | original_update_refname(update)); | |
3632 | else | |
3633 | strbuf_addf(err, "cannot lock ref '%s': is at %s but expected %s", | |
3634 | original_update_refname(update), | |
3635 | sha1_to_hex(lock->old_oid.hash), | |
3636 | sha1_to_hex(update->old_sha1)); | |
3637 | ||
3638 | return TRANSACTION_GENERIC_ERROR; | |
3639 | } | |
3640 | } | |
3641 | ||
3642 | if ((update->flags & REF_HAVE_NEW) && | |
3643 | !(update->flags & REF_DELETING) && | |
3644 | !(update->flags & REF_LOG_ONLY)) { | |
3645 | if (!(update->type & REF_ISSYMREF) && | |
3646 | !hashcmp(lock->old_oid.hash, update->new_sha1)) { | |
3647 | /* | |
3648 | * The reference already has the desired | |
3649 | * value, so we don't need to write it. | |
3650 | */ | |
3651 | } else if (write_ref_to_lockfile(lock, update->new_sha1, | |
3652 | err)) { | |
3653 | char *write_err = strbuf_detach(err, NULL); | |
3654 | ||
3655 | /* | |
3656 | * The lock was freed upon failure of | |
3657 | * write_ref_to_lockfile(): | |
3658 | */ | |
3659 | update->lock = NULL; | |
3660 | strbuf_addf(err, | |
3661 | "cannot update the ref '%s': %s", | |
3662 | update->refname, write_err); | |
3663 | free(write_err); | |
3664 | return TRANSACTION_GENERIC_ERROR; | |
3665 | } else { | |
3666 | update->flags |= REF_NEEDS_COMMIT; | |
3667 | } | |
3668 | } | |
3669 | if (!(update->flags & REF_NEEDS_COMMIT)) { | |
3670 | /* | |
3671 | * We didn't call write_ref_to_lockfile(), so | |
3672 | * the lockfile is still open. Close it to | |
3673 | * free up the file descriptor: | |
3674 | */ | |
3675 | if (close_ref(lock)) { | |
3676 | strbuf_addf(err, "couldn't close '%s.lock'", | |
3677 | update->refname); | |
3678 | return TRANSACTION_GENERIC_ERROR; | |
3679 | } | |
3680 | } | |
3681 | return 0; | |
3682 | } | |
3683 | ||
3684 | int ref_transaction_commit(struct ref_transaction *transaction, | |
3685 | struct strbuf *err) | |
3686 | { | |
3687 | int ret = 0, i; | |
3688 | struct string_list refs_to_delete = STRING_LIST_INIT_NODUP; | |
3689 | struct string_list_item *ref_to_delete; | |
3690 | struct string_list affected_refnames = STRING_LIST_INIT_NODUP; | |
3691 | char *head_ref = NULL; | |
3692 | int head_type; | |
3693 | struct object_id head_oid; | |
3694 | ||
3695 | assert(err); | |
3696 | ||
3697 | if (transaction->state != REF_TRANSACTION_OPEN) | |
3698 | die("BUG: commit called for transaction that is not open"); | |
3699 | ||
3700 | if (!transaction->nr) { | |
3701 | transaction->state = REF_TRANSACTION_CLOSED; | |
3702 | return 0; | |
3703 | } | |
3704 | ||
3705 | /* | |
3706 | * Fail if a refname appears more than once in the | |
3707 | * transaction. (If we end up splitting up any updates using | |
3708 | * split_symref_update() or split_head_update(), those | |
3709 | * functions will check that the new updates don't have the | |
3710 | * same refname as any existing ones.) | |
3711 | */ | |
3712 | for (i = 0; i < transaction->nr; i++) { | |
3713 | struct ref_update *update = transaction->updates[i]; | |
3714 | struct string_list_item *item = | |
3715 | string_list_append(&affected_refnames, update->refname); | |
3716 | ||
3717 | /* | |
3718 | * We store a pointer to update in item->util, but at | |
3719 | * the moment we never use the value of this field | |
3720 | * except to check whether it is non-NULL. | |
3721 | */ | |
3722 | item->util = update; | |
3723 | } | |
3724 | string_list_sort(&affected_refnames); | |
3725 | if (ref_update_reject_duplicates(&affected_refnames, err)) { | |
3726 | ret = TRANSACTION_GENERIC_ERROR; | |
3727 | goto cleanup; | |
3728 | } | |
3729 | ||
3730 | /* | |
3731 | * Special hack: If a branch is updated directly and HEAD | |
3732 | * points to it (may happen on the remote side of a push | |
3733 | * for example) then logically the HEAD reflog should be | |
3734 | * updated too. | |
3735 | * | |
3736 | * A generic solution would require reverse symref lookups, | |
3737 | * but finding all symrefs pointing to a given branch would be | |
3738 | * rather costly for this rare event (the direct update of a | |
3739 | * branch) to be worth it. So let's cheat and check with HEAD | |
3740 | * only, which should cover 99% of all usage scenarios (even | |
3741 | * 100% of the default ones). | |
3742 | * | |
3743 | * So if HEAD is a symbolic reference, then record the name of | |
3744 | * the reference that it points to. If we see an update of | |
3745 | * head_ref within the transaction, then split_head_update() | |
3746 | * arranges for the reflog of HEAD to be updated, too. | |
3747 | */ | |
3748 | head_ref = resolve_refdup("HEAD", RESOLVE_REF_NO_RECURSE, | |
3749 | head_oid.hash, &head_type); | |
3750 | ||
3751 | if (head_ref && !(head_type & REF_ISSYMREF)) { | |
3752 | free(head_ref); | |
3753 | head_ref = NULL; | |
3754 | } | |
3755 | ||
3756 | /* | |
3757 | * Acquire all locks, verify old values if provided, check | |
3758 | * that new values are valid, and write new values to the | |
3759 | * lockfiles, ready to be activated. Only keep one lockfile | |
3760 | * open at a time to avoid running out of file descriptors. | |
3761 | */ | |
3762 | for (i = 0; i < transaction->nr; i++) { | |
3763 | struct ref_update *update = transaction->updates[i]; | |
3764 | ||
3765 | ret = lock_ref_for_update(update, transaction, head_ref, | |
3766 | &affected_refnames, err); | |
3767 | if (ret) | |
3768 | goto cleanup; | |
3769 | } | |
3770 | ||
3771 | /* Perform updates first so live commits remain referenced */ | |
3772 | for (i = 0; i < transaction->nr; i++) { | |
3773 | struct ref_update *update = transaction->updates[i]; | |
3774 | struct ref_lock *lock = update->lock; | |
3775 | ||
3776 | if (update->flags & REF_NEEDS_COMMIT || | |
3777 | update->flags & REF_LOG_ONLY) { | |
3778 | if (log_ref_write(lock->ref_name, lock->old_oid.hash, | |
3779 | update->new_sha1, | |
3780 | update->msg, update->flags, err)) { | |
3781 | char *old_msg = strbuf_detach(err, NULL); | |
3782 | ||
3783 | strbuf_addf(err, "cannot update the ref '%s': %s", | |
3784 | lock->ref_name, old_msg); | |
3785 | free(old_msg); | |
3786 | unlock_ref(lock); | |
3787 | update->lock = NULL; | |
3788 | ret = TRANSACTION_GENERIC_ERROR; | |
3789 | goto cleanup; | |
3790 | } | |
3791 | } | |
3792 | if (update->flags & REF_NEEDS_COMMIT) { | |
3793 | clear_loose_ref_cache(&ref_store); | |
3794 | if (commit_ref(lock)) { | |
3795 | strbuf_addf(err, "couldn't set '%s'", lock->ref_name); | |
3796 | unlock_ref(lock); | |
3797 | update->lock = NULL; | |
3798 | ret = TRANSACTION_GENERIC_ERROR; | |
3799 | goto cleanup; | |
3800 | } | |
3801 | } | |
3802 | } | |
3803 | /* Perform deletes now that updates are safely completed */ | |
3804 | for (i = 0; i < transaction->nr; i++) { | |
3805 | struct ref_update *update = transaction->updates[i]; | |
3806 | ||
3807 | if (update->flags & REF_DELETING && | |
3808 | !(update->flags & REF_LOG_ONLY)) { | |
3809 | if (delete_ref_loose(update->lock, update->type, err)) { | |
3810 | ret = TRANSACTION_GENERIC_ERROR; | |
3811 | goto cleanup; | |
3812 | } | |
3813 | ||
3814 | if (!(update->flags & REF_ISPRUNING)) | |
3815 | string_list_append(&refs_to_delete, | |
3816 | update->lock->ref_name); | |
3817 | } | |
3818 | } | |
3819 | ||
3820 | if (repack_without_refs(&refs_to_delete, err)) { | |
3821 | ret = TRANSACTION_GENERIC_ERROR; | |
3822 | goto cleanup; | |
3823 | } | |
3824 | for_each_string_list_item(ref_to_delete, &refs_to_delete) | |
3825 | unlink_or_warn(git_path("logs/%s", ref_to_delete->string)); | |
3826 | clear_loose_ref_cache(&ref_store); | |
3827 | ||
3828 | cleanup: | |
3829 | transaction->state = REF_TRANSACTION_CLOSED; | |
3830 | ||
3831 | for (i = 0; i < transaction->nr; i++) | |
3832 | if (transaction->updates[i]->lock) | |
3833 | unlock_ref(transaction->updates[i]->lock); | |
3834 | string_list_clear(&refs_to_delete, 0); | |
3835 | free(head_ref); | |
3836 | string_list_clear(&affected_refnames, 0); | |
3837 | ||
3838 | return ret; | |
3839 | } | |
3840 | ||
3841 | static int ref_present(const char *refname, | |
3842 | const struct object_id *oid, int flags, void *cb_data) | |
3843 | { | |
3844 | struct string_list *affected_refnames = cb_data; | |
3845 | ||
3846 | return string_list_has_string(affected_refnames, refname); | |
3847 | } | |
3848 | ||
3849 | int initial_ref_transaction_commit(struct ref_transaction *transaction, | |
3850 | struct strbuf *err) | |
3851 | { | |
3852 | int ret = 0, i; | |
3853 | struct string_list affected_refnames = STRING_LIST_INIT_NODUP; | |
3854 | ||
3855 | assert(err); | |
3856 | ||
3857 | if (transaction->state != REF_TRANSACTION_OPEN) | |
3858 | die("BUG: commit called for transaction that is not open"); | |
3859 | ||
3860 | /* Fail if a refname appears more than once in the transaction: */ | |
3861 | for (i = 0; i < transaction->nr; i++) | |
3862 | string_list_append(&affected_refnames, | |
3863 | transaction->updates[i]->refname); | |
3864 | string_list_sort(&affected_refnames); | |
3865 | if (ref_update_reject_duplicates(&affected_refnames, err)) { | |
3866 | ret = TRANSACTION_GENERIC_ERROR; | |
3867 | goto cleanup; | |
3868 | } | |
3869 | ||
3870 | /* | |
3871 | * It's really undefined to call this function in an active | |
3872 | * repository or when there are existing references: we are | |
3873 | * only locking and changing packed-refs, so (1) any | |
3874 | * simultaneous processes might try to change a reference at | |
3875 | * the same time we do, and (2) any existing loose versions of | |
3876 | * the references that we are setting would have precedence | |
3877 | * over our values. But some remote helpers create the remote | |
3878 | * "HEAD" and "master" branches before calling this function, | |
3879 | * so here we really only check that none of the references | |
3880 | * that we are creating already exists. | |
3881 | */ | |
3882 | if (for_each_rawref(ref_present, &affected_refnames)) | |
3883 | die("BUG: initial ref transaction called with existing refs"); | |
3884 | ||
3885 | for (i = 0; i < transaction->nr; i++) { | |
3886 | struct ref_update *update = transaction->updates[i]; | |
3887 | ||
3888 | if ((update->flags & REF_HAVE_OLD) && | |
3889 | !is_null_sha1(update->old_sha1)) | |
3890 | die("BUG: initial ref transaction with old_sha1 set"); | |
3891 | if (verify_refname_available(update->refname, | |
3892 | &affected_refnames, NULL, | |
3893 | err)) { | |
3894 | ret = TRANSACTION_NAME_CONFLICT; | |
3895 | goto cleanup; | |
3896 | } | |
3897 | } | |
3898 | ||
3899 | if (lock_packed_refs(0)) { | |
3900 | strbuf_addf(err, "unable to lock packed-refs file: %s", | |
3901 | strerror(errno)); | |
3902 | ret = TRANSACTION_GENERIC_ERROR; | |
3903 | goto cleanup; | |
3904 | } | |
3905 | ||
3906 | for (i = 0; i < transaction->nr; i++) { | |
3907 | struct ref_update *update = transaction->updates[i]; | |
3908 | ||
3909 | if ((update->flags & REF_HAVE_NEW) && | |
3910 | !is_null_sha1(update->new_sha1)) | |
3911 | add_packed_ref(update->refname, update->new_sha1); | |
3912 | } | |
3913 | ||
3914 | if (commit_packed_refs()) { | |
3915 | strbuf_addf(err, "unable to commit packed-refs file: %s", | |
3916 | strerror(errno)); | |
3917 | ret = TRANSACTION_GENERIC_ERROR; | |
3918 | goto cleanup; | |
3919 | } | |
3920 | ||
3921 | cleanup: | |
3922 | transaction->state = REF_TRANSACTION_CLOSED; | |
3923 | string_list_clear(&affected_refnames, 0); | |
3924 | return ret; | |
3925 | } | |
3926 | ||
3927 | struct expire_reflog_cb { | |
3928 | unsigned int flags; | |
3929 | reflog_expiry_should_prune_fn *should_prune_fn; | |
3930 | void *policy_cb; | |
3931 | FILE *newlog; | |
3932 | unsigned char last_kept_sha1[20]; | |
3933 | }; | |
3934 | ||
3935 | static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1, | |
3936 | const char *email, unsigned long timestamp, int tz, | |
3937 | const char *message, void *cb_data) | |
3938 | { | |
3939 | struct expire_reflog_cb *cb = cb_data; | |
3940 | struct expire_reflog_policy_cb *policy_cb = cb->policy_cb; | |
3941 | ||
3942 | if (cb->flags & EXPIRE_REFLOGS_REWRITE) | |
3943 | osha1 = cb->last_kept_sha1; | |
3944 | ||
3945 | if ((*cb->should_prune_fn)(osha1, nsha1, email, timestamp, tz, | |
3946 | message, policy_cb)) { | |
3947 | if (!cb->newlog) | |
3948 | printf("would prune %s", message); | |
3949 | else if (cb->flags & EXPIRE_REFLOGS_VERBOSE) | |
3950 | printf("prune %s", message); | |
3951 | } else { | |
3952 | if (cb->newlog) { | |
3953 | fprintf(cb->newlog, "%s %s %s %lu %+05d\t%s", | |
3954 | sha1_to_hex(osha1), sha1_to_hex(nsha1), | |
3955 | email, timestamp, tz, message); | |
3956 | hashcpy(cb->last_kept_sha1, nsha1); | |
3957 | } | |
3958 | if (cb->flags & EXPIRE_REFLOGS_VERBOSE) | |
3959 | printf("keep %s", message); | |
3960 | } | |
3961 | return 0; | |
3962 | } | |
3963 | ||
3964 | int reflog_expire(const char *refname, const unsigned char *sha1, | |
3965 | unsigned int flags, | |
3966 | reflog_expiry_prepare_fn prepare_fn, | |
3967 | reflog_expiry_should_prune_fn should_prune_fn, | |
3968 | reflog_expiry_cleanup_fn cleanup_fn, | |
3969 | void *policy_cb_data) | |
3970 | { | |
3971 | static struct lock_file reflog_lock; | |
3972 | struct expire_reflog_cb cb; | |
3973 | struct ref_lock *lock; | |
3974 | char *log_file; | |
3975 | int status = 0; | |
3976 | int type; | |
3977 | struct strbuf err = STRBUF_INIT; | |
3978 | ||
3979 | memset(&cb, 0, sizeof(cb)); | |
3980 | cb.flags = flags; | |
3981 | cb.policy_cb = policy_cb_data; | |
3982 | cb.should_prune_fn = should_prune_fn; | |
3983 | ||
3984 | /* | |
3985 | * The reflog file is locked by holding the lock on the | |
3986 | * reference itself, plus we might need to update the | |
3987 | * reference if --updateref was specified: | |
3988 | */ | |
3989 | lock = lock_ref_sha1_basic(refname, sha1, NULL, NULL, REF_NODEREF, | |
3990 | &type, &err); | |
3991 | if (!lock) { | |
3992 | error("cannot lock ref '%s': %s", refname, err.buf); | |
3993 | strbuf_release(&err); | |
3994 | return -1; | |
3995 | } | |
3996 | if (!reflog_exists(refname)) { | |
3997 | unlock_ref(lock); | |
3998 | return 0; | |
3999 | } | |
4000 | ||
4001 | log_file = git_pathdup("logs/%s", refname); | |
4002 | if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) { | |
4003 | /* | |
4004 | * Even though holding $GIT_DIR/logs/$reflog.lock has | |
4005 | * no locking implications, we use the lock_file | |
4006 | * machinery here anyway because it does a lot of the | |
4007 | * work we need, including cleaning up if the program | |
4008 | * exits unexpectedly. | |
4009 | */ | |
4010 | if (hold_lock_file_for_update(&reflog_lock, log_file, 0) < 0) { | |
4011 | struct strbuf err = STRBUF_INIT; | |
4012 | unable_to_lock_message(log_file, errno, &err); | |
4013 | error("%s", err.buf); | |
4014 | strbuf_release(&err); | |
4015 | goto failure; | |
4016 | } | |
4017 | cb.newlog = fdopen_lock_file(&reflog_lock, "w"); | |
4018 | if (!cb.newlog) { | |
4019 | error("cannot fdopen %s (%s)", | |
4020 | get_lock_file_path(&reflog_lock), strerror(errno)); | |
4021 | goto failure; | |
4022 | } | |
4023 | } | |
4024 | ||
4025 | (*prepare_fn)(refname, sha1, cb.policy_cb); | |
4026 | for_each_reflog_ent(refname, expire_reflog_ent, &cb); | |
4027 | (*cleanup_fn)(cb.policy_cb); | |
4028 | ||
4029 | if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) { | |
4030 | /* | |
4031 | * It doesn't make sense to adjust a reference pointed | |
4032 | * to by a symbolic ref based on expiring entries in | |
4033 | * the symbolic reference's reflog. Nor can we update | |
4034 | * a reference if there are no remaining reflog | |
4035 | * entries. | |
4036 | */ | |
4037 | int update = (flags & EXPIRE_REFLOGS_UPDATE_REF) && | |
4038 | !(type & REF_ISSYMREF) && | |
4039 | !is_null_sha1(cb.last_kept_sha1); | |
4040 | ||
4041 | if (close_lock_file(&reflog_lock)) { | |
4042 | status |= error("couldn't write %s: %s", log_file, | |
4043 | strerror(errno)); | |
4044 | } else if (update && | |
4045 | (write_in_full(get_lock_file_fd(lock->lk), | |
4046 | sha1_to_hex(cb.last_kept_sha1), 40) != 40 || | |
4047 | write_str_in_full(get_lock_file_fd(lock->lk), "\n") != 1 || | |
4048 | close_ref(lock) < 0)) { | |
4049 | status |= error("couldn't write %s", | |
4050 | get_lock_file_path(lock->lk)); | |
4051 | rollback_lock_file(&reflog_lock); | |
4052 | } else if (commit_lock_file(&reflog_lock)) { | |
4053 | status |= error("unable to write reflog '%s' (%s)", | |
4054 | log_file, strerror(errno)); | |
4055 | } else if (update && commit_ref(lock)) { | |
4056 | status |= error("couldn't set %s", lock->ref_name); | |
4057 | } | |
4058 | } | |
4059 | free(log_file); | |
4060 | unlock_ref(lock); | |
4061 | return status; | |
4062 | ||
4063 | failure: | |
4064 | rollback_lock_file(&reflog_lock); | |
4065 | free(log_file); | |
4066 | unlock_ref(lock); | |
4067 | return -1; | |
4068 | } | |
4069 | ||
4070 | struct ref_storage_be refs_be_files = { | |
4071 | NULL, | |
4072 | "files" | |
4073 | }; |