Merge branch 'sb/retire-t1200'
[git/git.git] / refs / refs-internal.h
1 #ifndef REFS_REFS_INTERNAL_H
2 #define REFS_REFS_INTERNAL_H
3
4 /*
5 * Data structures and functions for the internal use of the refs
6 * module. Code outside of the refs module should use only the public
7 * functions defined in "refs.h", and should *not* include this file.
8 */
9
10 /*
11 * Flag passed to lock_ref_sha1_basic() telling it to tolerate broken
12 * refs (i.e., because the reference is about to be deleted anyway).
13 */
14 #define REF_DELETING 0x02
15
16 /*
17 * Used as a flag in ref_update::flags when a loose ref is being
18 * pruned. This flag must only be used when REF_NODEREF is set.
19 */
20 #define REF_ISPRUNING 0x04
21
22 /*
23 * Used as a flag in ref_update::flags when the reference should be
24 * updated to new_sha1.
25 */
26 #define REF_HAVE_NEW 0x08
27
28 /*
29 * Used as a flag in ref_update::flags when old_sha1 should be
30 * checked.
31 */
32 #define REF_HAVE_OLD 0x10
33
34 /*
35 * Used as a flag in ref_update::flags when the lockfile needs to be
36 * committed.
37 */
38 #define REF_NEEDS_COMMIT 0x20
39
40 /*
41 * 0x40 is REF_FORCE_CREATE_REFLOG, so skip it if you're adding a
42 * value to ref_update::flags
43 */
44
45 /*
46 * Used as a flag in ref_update::flags when we want to log a ref
47 * update but not actually perform it. This is used when a symbolic
48 * ref update is split up.
49 */
50 #define REF_LOG_ONLY 0x80
51
52 /*
53 * Internal flag, meaning that the containing ref_update was via an
54 * update to HEAD.
55 */
56 #define REF_UPDATE_VIA_HEAD 0x100
57
58 /*
59 * Used as a flag in ref_update::flags when the loose reference has
60 * been deleted.
61 */
62 #define REF_DELETED_LOOSE 0x200
63
64 /*
65 * Return true iff refname is minimally safe. "Safe" here means that
66 * deleting a loose reference by this name will not do any damage, for
67 * example by causing a file that is not a reference to be deleted.
68 * This function does not check that the reference name is legal; for
69 * that, use check_refname_format().
70 *
71 * A refname that starts with "refs/" is considered safe iff it
72 * doesn't contain any "." or ".." components or consecutive '/'
73 * characters, end with '/', or (on Windows) contain any '\'
74 * characters. Names that do not start with "refs/" are considered
75 * safe iff they consist entirely of upper case characters and '_'
76 * (like "HEAD" and "MERGE_HEAD" but not "config" or "FOO/BAR").
77 */
78 int refname_is_safe(const char *refname);
79
80 enum peel_status {
81 /* object was peeled successfully: */
82 PEEL_PEELED = 0,
83
84 /*
85 * object cannot be peeled because the named object (or an
86 * object referred to by a tag in the peel chain), does not
87 * exist.
88 */
89 PEEL_INVALID = -1,
90
91 /* object cannot be peeled because it is not a tag: */
92 PEEL_NON_TAG = -2,
93
94 /* ref_entry contains no peeled value because it is a symref: */
95 PEEL_IS_SYMREF = -3,
96
97 /*
98 * ref_entry cannot be peeled because it is broken (i.e., the
99 * symbolic reference cannot even be resolved to an object
100 * name):
101 */
102 PEEL_BROKEN = -4
103 };
104
105 /*
106 * Peel the named object; i.e., if the object is a tag, resolve the
107 * tag recursively until a non-tag is found. If successful, store the
108 * result to sha1 and return PEEL_PEELED. If the object is not a tag
109 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
110 * and leave sha1 unchanged.
111 */
112 enum peel_status peel_object(const unsigned char *name, unsigned char *sha1);
113
114 /*
115 * Copy the reflog message msg to buf, which has been allocated sufficiently
116 * large, while cleaning up the whitespaces. Especially, convert LF to space,
117 * because reflog file is one line per entry.
118 */
119 int copy_reflog_msg(char *buf, const char *msg);
120
121 /**
122 * Information needed for a single ref update. Set new_sha1 to the new
123 * value or to null_sha1 to delete the ref. To check the old value
124 * while the ref is locked, set (flags & REF_HAVE_OLD) and set
125 * old_sha1 to the old value, or to null_sha1 to ensure the ref does
126 * not exist before update.
127 */
128 struct ref_update {
129
130 /*
131 * If (flags & REF_HAVE_NEW), set the reference to this value:
132 */
133 struct object_id new_oid;
134
135 /*
136 * If (flags & REF_HAVE_OLD), check that the reference
137 * previously had this value:
138 */
139 struct object_id old_oid;
140
141 /*
142 * One or more of REF_HAVE_NEW, REF_HAVE_OLD, REF_NODEREF,
143 * REF_DELETING, REF_ISPRUNING, REF_LOG_ONLY,
144 * REF_UPDATE_VIA_HEAD, REF_NEEDS_COMMIT, and
145 * REF_DELETED_LOOSE:
146 */
147 unsigned int flags;
148
149 void *backend_data;
150 unsigned int type;
151 char *msg;
152
153 /*
154 * If this ref_update was split off of a symref update via
155 * split_symref_update(), then this member points at that
156 * update. This is used for two purposes:
157 * 1. When reporting errors, we report the refname under which
158 * the update was originally requested.
159 * 2. When we read the old value of this reference, we
160 * propagate it back to its parent update for recording in
161 * the latter's reflog.
162 */
163 struct ref_update *parent_update;
164
165 const char refname[FLEX_ARRAY];
166 };
167
168 int refs_read_raw_ref(struct ref_store *ref_store,
169 const char *refname, unsigned char *sha1,
170 struct strbuf *referent, unsigned int *type);
171
172 /*
173 * Write an error to `err` and return a nonzero value iff the same
174 * refname appears multiple times in `refnames`. `refnames` must be
175 * sorted on entry to this function.
176 */
177 int ref_update_reject_duplicates(struct string_list *refnames,
178 struct strbuf *err);
179
180 /*
181 * Add a ref_update with the specified properties to transaction, and
182 * return a pointer to the new object. This function does not verify
183 * that refname is well-formed. new_sha1 and old_sha1 are only
184 * dereferenced if the REF_HAVE_NEW and REF_HAVE_OLD bits,
185 * respectively, are set in flags.
186 */
187 struct ref_update *ref_transaction_add_update(
188 struct ref_transaction *transaction,
189 const char *refname, unsigned int flags,
190 const unsigned char *new_sha1,
191 const unsigned char *old_sha1,
192 const char *msg);
193
194 /*
195 * Transaction states.
196 *
197 * OPEN: The transaction is initialized and new updates can still be
198 * added to it. An OPEN transaction can be prepared,
199 * committed, freed, or aborted (freeing and aborting an open
200 * transaction are equivalent).
201 *
202 * PREPARED: ref_transaction_prepare(), which locks all of the
203 * references involved in the update and checks that the
204 * update has no errors, has been called successfully for the
205 * transaction. A PREPARED transaction can be committed or
206 * aborted.
207 *
208 * CLOSED: The transaction is no longer active. A transaction becomes
209 * CLOSED if there is a failure while building the transaction
210 * or if a transaction is committed or aborted. A CLOSED
211 * transaction can only be freed.
212 */
213 enum ref_transaction_state {
214 REF_TRANSACTION_OPEN = 0,
215 REF_TRANSACTION_PREPARED = 1,
216 REF_TRANSACTION_CLOSED = 2
217 };
218
219 /*
220 * Data structure for holding a reference transaction, which can
221 * consist of checks and updates to multiple references, carried out
222 * as atomically as possible. This structure is opaque to callers.
223 */
224 struct ref_transaction {
225 struct ref_store *ref_store;
226 struct ref_update **updates;
227 size_t alloc;
228 size_t nr;
229 enum ref_transaction_state state;
230 };
231
232 /*
233 * Check for entries in extras that are within the specified
234 * directory, where dirname is a reference directory name including
235 * the trailing slash (e.g., "refs/heads/foo/"). Ignore any
236 * conflicting references that are found in skip. If there is a
237 * conflicting reference, return its name.
238 *
239 * extras and skip must be sorted lists of reference names. Either one
240 * can be NULL, signifying the empty list.
241 */
242 const char *find_descendant_ref(const char *dirname,
243 const struct string_list *extras,
244 const struct string_list *skip);
245
246 /*
247 * Check whether an attempt to rename old_refname to new_refname would
248 * cause a D/F conflict with any existing reference (other than
249 * possibly old_refname). If there would be a conflict, emit an error
250 * message and return false; otherwise, return true.
251 *
252 * Note that this function is not safe against all races with other
253 * processes (though rename_ref() catches some races that might get by
254 * this check).
255 */
256 int refs_rename_ref_available(struct ref_store *refs,
257 const char *old_refname,
258 const char *new_refname);
259
260 /* We allow "recursive" symbolic refs. Only within reason, though */
261 #define SYMREF_MAXDEPTH 5
262
263 /* Include broken references in a do_for_each_ref*() iteration: */
264 #define DO_FOR_EACH_INCLUDE_BROKEN 0x01
265
266 /*
267 * Reference iterators
268 *
269 * A reference iterator encapsulates the state of an in-progress
270 * iteration over references. Create an instance of `struct
271 * ref_iterator` via one of the functions in this module.
272 *
273 * A freshly-created ref_iterator doesn't yet point at a reference. To
274 * advance the iterator, call ref_iterator_advance(). If successful,
275 * this sets the iterator's refname, oid, and flags fields to describe
276 * the next reference and returns ITER_OK. The data pointed at by
277 * refname and oid belong to the iterator; if you want to retain them
278 * after calling ref_iterator_advance() again or calling
279 * ref_iterator_abort(), you must make a copy. When the iteration has
280 * been exhausted, ref_iterator_advance() releases any resources
281 * assocated with the iteration, frees the ref_iterator object, and
282 * returns ITER_DONE. If you want to abort the iteration early, call
283 * ref_iterator_abort(), which also frees the ref_iterator object and
284 * any associated resources. If there was an internal error advancing
285 * to the next entry, ref_iterator_advance() aborts the iteration,
286 * frees the ref_iterator, and returns ITER_ERROR.
287 *
288 * The reference currently being looked at can be peeled by calling
289 * ref_iterator_peel(). This function is often faster than peel_ref(),
290 * so it should be preferred when iterating over references.
291 *
292 * Putting it all together, a typical iteration looks like this:
293 *
294 * int ok;
295 * struct ref_iterator *iter = ...;
296 *
297 * while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
298 * if (want_to_stop_iteration()) {
299 * ok = ref_iterator_abort(iter);
300 * break;
301 * }
302 *
303 * // Access information about the current reference:
304 * if (!(iter->flags & REF_ISSYMREF))
305 * printf("%s is %s\n", iter->refname, oid_to_hex(&iter->oid));
306 *
307 * // If you need to peel the reference:
308 * ref_iterator_peel(iter, &oid);
309 * }
310 *
311 * if (ok != ITER_DONE)
312 * handle_error();
313 */
314 struct ref_iterator {
315 struct ref_iterator_vtable *vtable;
316 const char *refname;
317 const struct object_id *oid;
318 unsigned int flags;
319 };
320
321 /*
322 * Advance the iterator to the first or next item and return ITER_OK.
323 * If the iteration is exhausted, free the resources associated with
324 * the ref_iterator and return ITER_DONE. On errors, free the iterator
325 * resources and return ITER_ERROR. It is a bug to use ref_iterator or
326 * call this function again after it has returned ITER_DONE or
327 * ITER_ERROR.
328 */
329 int ref_iterator_advance(struct ref_iterator *ref_iterator);
330
331 /*
332 * If possible, peel the reference currently being viewed by the
333 * iterator. Return 0 on success.
334 */
335 int ref_iterator_peel(struct ref_iterator *ref_iterator,
336 struct object_id *peeled);
337
338 /*
339 * End the iteration before it has been exhausted, freeing the
340 * reference iterator and any associated resources and returning
341 * ITER_DONE. If the abort itself failed, return ITER_ERROR.
342 */
343 int ref_iterator_abort(struct ref_iterator *ref_iterator);
344
345 /*
346 * An iterator over nothing (its first ref_iterator_advance() call
347 * returns ITER_DONE).
348 */
349 struct ref_iterator *empty_ref_iterator_begin(void);
350
351 /*
352 * Return true iff ref_iterator is an empty_ref_iterator.
353 */
354 int is_empty_ref_iterator(struct ref_iterator *ref_iterator);
355
356 /*
357 * Return an iterator that goes over each reference in `refs` for
358 * which the refname begins with prefix. If trim is non-zero, then
359 * trim that many characters off the beginning of each refname. flags
360 * can be DO_FOR_EACH_INCLUDE_BROKEN to include broken references in
361 * the iteration.
362 */
363 struct ref_iterator *refs_ref_iterator_begin(
364 struct ref_store *refs,
365 const char *prefix, int trim, int flags);
366
367 /*
368 * A callback function used to instruct merge_ref_iterator how to
369 * interleave the entries from iter0 and iter1. The function should
370 * return one of the constants defined in enum iterator_selection. It
371 * must not advance either of the iterators itself.
372 *
373 * The function must be prepared to handle the case that iter0 and/or
374 * iter1 is NULL, which indicates that the corresponding sub-iterator
375 * has been exhausted. Its return value must be consistent with the
376 * current states of the iterators; e.g., it must not return
377 * ITER_SKIP_1 if iter1 has already been exhausted.
378 */
379 typedef enum iterator_selection ref_iterator_select_fn(
380 struct ref_iterator *iter0, struct ref_iterator *iter1,
381 void *cb_data);
382
383 /*
384 * Iterate over the entries from iter0 and iter1, with the values
385 * interleaved as directed by the select function. The iterator takes
386 * ownership of iter0 and iter1 and frees them when the iteration is
387 * over.
388 */
389 struct ref_iterator *merge_ref_iterator_begin(
390 struct ref_iterator *iter0, struct ref_iterator *iter1,
391 ref_iterator_select_fn *select, void *cb_data);
392
393 /*
394 * An iterator consisting of the union of the entries from front and
395 * back. If there are entries common to the two sub-iterators, use the
396 * one from front. Each iterator must iterate over its entries in
397 * strcmp() order by refname for this to work.
398 *
399 * The new iterator takes ownership of its arguments and frees them
400 * when the iteration is over. As a convenience to callers, if front
401 * or back is an empty_ref_iterator, then abort that one immediately
402 * and return the other iterator directly, without wrapping it.
403 */
404 struct ref_iterator *overlay_ref_iterator_begin(
405 struct ref_iterator *front, struct ref_iterator *back);
406
407 /*
408 * Wrap iter0, only letting through the references whose names start
409 * with prefix. If trim is set, set iter->refname to the name of the
410 * reference with that many characters trimmed off the front;
411 * otherwise set it to the full refname. The new iterator takes over
412 * ownership of iter0 and frees it when iteration is over. It makes
413 * its own copy of prefix.
414 *
415 * As an convenience to callers, if prefix is the empty string and
416 * trim is zero, this function returns iter0 directly, without
417 * wrapping it.
418 */
419 struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
420 const char *prefix,
421 int trim);
422
423 /* Internal implementation of reference iteration: */
424
425 /*
426 * Base class constructor for ref_iterators. Initialize the
427 * ref_iterator part of iter, setting its vtable pointer as specified.
428 * This is meant to be called only by the initializers of derived
429 * classes.
430 */
431 void base_ref_iterator_init(struct ref_iterator *iter,
432 struct ref_iterator_vtable *vtable);
433
434 /*
435 * Base class destructor for ref_iterators. Destroy the ref_iterator
436 * part of iter and shallow-free the object. This is meant to be
437 * called only by the destructors of derived classes.
438 */
439 void base_ref_iterator_free(struct ref_iterator *iter);
440
441 /* Virtual function declarations for ref_iterators: */
442
443 typedef int ref_iterator_advance_fn(struct ref_iterator *ref_iterator);
444
445 typedef int ref_iterator_peel_fn(struct ref_iterator *ref_iterator,
446 struct object_id *peeled);
447
448 /*
449 * Implementations of this function should free any resources specific
450 * to the derived class, then call base_ref_iterator_free() to clean
451 * up and free the ref_iterator object.
452 */
453 typedef int ref_iterator_abort_fn(struct ref_iterator *ref_iterator);
454
455 struct ref_iterator_vtable {
456 ref_iterator_advance_fn *advance;
457 ref_iterator_peel_fn *peel;
458 ref_iterator_abort_fn *abort;
459 };
460
461 /*
462 * current_ref_iter is a performance hack: when iterating over
463 * references using the for_each_ref*() functions, current_ref_iter is
464 * set to the reference iterator before calling the callback function.
465 * If the callback function calls peel_ref(), then peel_ref() first
466 * checks whether the reference to be peeled is the one referred to by
467 * the iterator (it usually is) and if so, asks the iterator for the
468 * peeled version of the reference if it is available. This avoids a
469 * refname lookup in a common case. current_ref_iter is set to NULL
470 * when the iteration is over.
471 */
472 extern struct ref_iterator *current_ref_iter;
473
474 /*
475 * The common backend for the for_each_*ref* functions. Call fn for
476 * each reference in iter. If the iterator itself ever returns
477 * ITER_ERROR, return -1. If fn ever returns a non-zero value, stop
478 * the iteration and return that value. Otherwise, return 0. In any
479 * case, free the iterator when done. This function is basically an
480 * adapter between the callback style of reference iteration and the
481 * iterator style.
482 */
483 int do_for_each_ref_iterator(struct ref_iterator *iter,
484 each_ref_fn fn, void *cb_data);
485
486 /*
487 * Only include per-worktree refs in a do_for_each_ref*() iteration.
488 * Normally this will be used with a files ref_store, since that's
489 * where all reference backends will presumably store their
490 * per-worktree refs.
491 */
492 #define DO_FOR_EACH_PER_WORKTREE_ONLY 0x02
493
494 struct ref_store;
495
496 /* refs backends */
497
498 /* ref_store_init flags */
499 #define REF_STORE_READ (1 << 0)
500 #define REF_STORE_WRITE (1 << 1) /* can perform update operations */
501 #define REF_STORE_ODB (1 << 2) /* has access to object database */
502 #define REF_STORE_MAIN (1 << 3)
503 #define REF_STORE_ALL_CAPS (REF_STORE_READ | \
504 REF_STORE_WRITE | \
505 REF_STORE_ODB | \
506 REF_STORE_MAIN)
507
508 /*
509 * Initialize the ref_store for the specified gitdir. These functions
510 * should call base_ref_store_init() to initialize the shared part of
511 * the ref_store and to record the ref_store for later lookup.
512 */
513 typedef struct ref_store *ref_store_init_fn(const char *gitdir,
514 unsigned int flags);
515
516 typedef int ref_init_db_fn(struct ref_store *refs, struct strbuf *err);
517
518 typedef int ref_transaction_prepare_fn(struct ref_store *refs,
519 struct ref_transaction *transaction,
520 struct strbuf *err);
521
522 typedef int ref_transaction_finish_fn(struct ref_store *refs,
523 struct ref_transaction *transaction,
524 struct strbuf *err);
525
526 typedef int ref_transaction_abort_fn(struct ref_store *refs,
527 struct ref_transaction *transaction,
528 struct strbuf *err);
529
530 typedef int ref_transaction_commit_fn(struct ref_store *refs,
531 struct ref_transaction *transaction,
532 struct strbuf *err);
533
534 typedef int pack_refs_fn(struct ref_store *ref_store, unsigned int flags);
535 typedef int peel_ref_fn(struct ref_store *ref_store,
536 const char *refname, unsigned char *sha1);
537 typedef int create_symref_fn(struct ref_store *ref_store,
538 const char *ref_target,
539 const char *refs_heads_master,
540 const char *logmsg);
541 typedef int delete_refs_fn(struct ref_store *ref_store, const char *msg,
542 struct string_list *refnames, unsigned int flags);
543 typedef int rename_ref_fn(struct ref_store *ref_store,
544 const char *oldref, const char *newref,
545 const char *logmsg);
546
547 /*
548 * Iterate over the references in `ref_store` whose names start with
549 * `prefix`. `prefix` is matched as a literal string, without regard
550 * for path separators. If prefix is NULL or the empty string, iterate
551 * over all references in `ref_store`.
552 */
553 typedef struct ref_iterator *ref_iterator_begin_fn(
554 struct ref_store *ref_store,
555 const char *prefix, unsigned int flags);
556
557 /* reflog functions */
558
559 /*
560 * Iterate over the references in the specified ref_store that have a
561 * reflog. The refs are iterated over in arbitrary order.
562 */
563 typedef struct ref_iterator *reflog_iterator_begin_fn(
564 struct ref_store *ref_store);
565
566 typedef int for_each_reflog_ent_fn(struct ref_store *ref_store,
567 const char *refname,
568 each_reflog_ent_fn fn,
569 void *cb_data);
570 typedef int for_each_reflog_ent_reverse_fn(struct ref_store *ref_store,
571 const char *refname,
572 each_reflog_ent_fn fn,
573 void *cb_data);
574 typedef int reflog_exists_fn(struct ref_store *ref_store, const char *refname);
575 typedef int create_reflog_fn(struct ref_store *ref_store, const char *refname,
576 int force_create, struct strbuf *err);
577 typedef int delete_reflog_fn(struct ref_store *ref_store, const char *refname);
578 typedef int reflog_expire_fn(struct ref_store *ref_store,
579 const char *refname, const unsigned char *sha1,
580 unsigned int flags,
581 reflog_expiry_prepare_fn prepare_fn,
582 reflog_expiry_should_prune_fn should_prune_fn,
583 reflog_expiry_cleanup_fn cleanup_fn,
584 void *policy_cb_data);
585
586 /*
587 * Read a reference from the specified reference store, non-recursively.
588 * Set type to describe the reference, and:
589 *
590 * - If refname is the name of a normal reference, fill in sha1
591 * (leaving referent unchanged).
592 *
593 * - If refname is the name of a symbolic reference, write the full
594 * name of the reference to which it refers (e.g.
595 * "refs/heads/master") to referent and set the REF_ISSYMREF bit in
596 * type (leaving sha1 unchanged). The caller is responsible for
597 * validating that referent is a valid reference name.
598 *
599 * WARNING: refname might be used as part of a filename, so it is
600 * important from a security standpoint that it be safe in the sense
601 * of refname_is_safe(). Moreover, for symrefs this function sets
602 * referent to whatever the repository says, which might not be a
603 * properly-formatted or even safe reference name. NEITHER INPUT NOR
604 * OUTPUT REFERENCE NAMES ARE VALIDATED WITHIN THIS FUNCTION.
605 *
606 * Return 0 on success. If the ref doesn't exist, set errno to ENOENT
607 * and return -1. If the ref exists but is neither a symbolic ref nor
608 * a sha1, it is broken; set REF_ISBROKEN in type, set errno to
609 * EINVAL, and return -1. If there is another error reading the ref,
610 * set errno appropriately and return -1.
611 *
612 * Backend-specific flags might be set in type as well, regardless of
613 * outcome.
614 *
615 * It is OK for refname to point into referent. If so:
616 *
617 * - if the function succeeds with REF_ISSYMREF, referent will be
618 * overwritten and the memory formerly pointed to by it might be
619 * changed or even freed.
620 *
621 * - in all other cases, referent will be untouched, and therefore
622 * refname will still be valid and unchanged.
623 */
624 typedef int read_raw_ref_fn(struct ref_store *ref_store,
625 const char *refname, unsigned char *sha1,
626 struct strbuf *referent, unsigned int *type);
627
628 struct ref_storage_be {
629 struct ref_storage_be *next;
630 const char *name;
631 ref_store_init_fn *init;
632 ref_init_db_fn *init_db;
633
634 ref_transaction_prepare_fn *transaction_prepare;
635 ref_transaction_finish_fn *transaction_finish;
636 ref_transaction_abort_fn *transaction_abort;
637 ref_transaction_commit_fn *initial_transaction_commit;
638
639 pack_refs_fn *pack_refs;
640 peel_ref_fn *peel_ref;
641 create_symref_fn *create_symref;
642 delete_refs_fn *delete_refs;
643 rename_ref_fn *rename_ref;
644
645 ref_iterator_begin_fn *iterator_begin;
646 read_raw_ref_fn *read_raw_ref;
647
648 reflog_iterator_begin_fn *reflog_iterator_begin;
649 for_each_reflog_ent_fn *for_each_reflog_ent;
650 for_each_reflog_ent_reverse_fn *for_each_reflog_ent_reverse;
651 reflog_exists_fn *reflog_exists;
652 create_reflog_fn *create_reflog;
653 delete_reflog_fn *delete_reflog;
654 reflog_expire_fn *reflog_expire;
655 };
656
657 extern struct ref_storage_be refs_be_files;
658
659 /*
660 * A representation of the reference store for the main repository or
661 * a submodule. The ref_store instances for submodules are kept in a
662 * linked list.
663 */
664 struct ref_store {
665 /* The backend describing this ref_store's storage scheme: */
666 const struct ref_storage_be *be;
667 };
668
669 /*
670 * Fill in the generic part of refs and add it to our collection of
671 * reference stores.
672 */
673 void base_ref_store_init(struct ref_store *refs,
674 const struct ref_storage_be *be);
675
676 #endif /* REFS_REFS_INTERNAL_H */