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