files_transaction_finish(): delete reflogs before references
[git/git.git] / refs / refs-internal.h
CommitLineData
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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
c52ce248 18 * pruned. This flag must only be used when REF_NODEREF is set.
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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
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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
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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
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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
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64/*
65 * Return the length of time to retry acquiring a loose reference lock
66 * before giving up, in milliseconds:
67 */
68long get_files_ref_lock_timeout_ms(void);
69
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70/*
71 * Return true iff refname is minimally safe. "Safe" here means that
72 * deleting a loose reference by this name will not do any damage, for
73 * example by causing a file that is not a reference to be deleted.
74 * This function does not check that the reference name is legal; for
75 * that, use check_refname_format().
76 *
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77 * A refname that starts with "refs/" is considered safe iff it
78 * doesn't contain any "." or ".." components or consecutive '/'
79 * characters, end with '/', or (on Windows) contain any '\'
80 * characters. Names that do not start with "refs/" are considered
81 * safe iff they consist entirely of upper case characters and '_'
82 * (like "HEAD" and "MERGE_HEAD" but not "config" or "FOO/BAR").
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83 */
84int refname_is_safe(const char *refname);
85
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86/*
87 * Helper function: return true if refname, which has the specified
88 * oid and flags, can be resolved to an object in the database. If the
89 * referred-to object does not exist, emit a warning and return false.
90 */
91int ref_resolves_to_object(const char *refname,
92 const struct object_id *oid,
93 unsigned int flags);
94
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95enum peel_status {
96 /* object was peeled successfully: */
97 PEEL_PEELED = 0,
98
99 /*
100 * object cannot be peeled because the named object (or an
101 * object referred to by a tag in the peel chain), does not
102 * exist.
103 */
104 PEEL_INVALID = -1,
105
106 /* object cannot be peeled because it is not a tag: */
107 PEEL_NON_TAG = -2,
108
109 /* ref_entry contains no peeled value because it is a symref: */
110 PEEL_IS_SYMREF = -3,
111
112 /*
113 * ref_entry cannot be peeled because it is broken (i.e., the
114 * symbolic reference cannot even be resolved to an object
115 * name):
116 */
117 PEEL_BROKEN = -4
118};
119
120/*
121 * Peel the named object; i.e., if the object is a tag, resolve the
122 * tag recursively until a non-tag is found. If successful, store the
123 * result to sha1 and return PEEL_PEELED. If the object is not a tag
124 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
125 * and leave sha1 unchanged.
126 */
127enum peel_status peel_object(const unsigned char *name, unsigned char *sha1);
128
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129/*
130 * Copy the reflog message msg to buf, which has been allocated sufficiently
131 * large, while cleaning up the whitespaces. Especially, convert LF to space,
132 * because reflog file is one line per entry.
133 */
134int copy_reflog_msg(char *buf, const char *msg);
135
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136/**
137 * Information needed for a single ref update. Set new_sha1 to the new
138 * value or to null_sha1 to delete the ref. To check the old value
139 * while the ref is locked, set (flags & REF_HAVE_OLD) and set
140 * old_sha1 to the old value, or to null_sha1 to ensure the ref does
141 * not exist before update.
142 */
143struct ref_update {
6e30b2f6 144
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145 /*
146 * If (flags & REF_HAVE_NEW), set the reference to this value:
147 */
98491298 148 struct object_id new_oid;
6e30b2f6 149
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150 /*
151 * If (flags & REF_HAVE_OLD), check that the reference
152 * previously had this value:
153 */
98491298 154 struct object_id old_oid;
6e30b2f6 155
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156 /*
157 * One or more of REF_HAVE_NEW, REF_HAVE_OLD, REF_NODEREF,
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158 * REF_DELETING, REF_ISPRUNING, REF_LOG_ONLY,
159 * REF_UPDATE_VIA_HEAD, REF_NEEDS_COMMIT, and
160 * REF_DELETED_LOOSE:
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161 */
162 unsigned int flags;
6e30b2f6 163
7d618264 164 void *backend_data;
92b1551b 165 unsigned int type;
4cb77009 166 char *msg;
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167
168 /*
169 * If this ref_update was split off of a symref update via
170 * split_symref_update(), then this member points at that
171 * update. This is used for two purposes:
172 * 1. When reporting errors, we report the refname under which
173 * the update was originally requested.
174 * 2. When we read the old value of this reference, we
175 * propagate it back to its parent update for recording in
176 * the latter's reflog.
177 */
178 struct ref_update *parent_update;
179
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180 const char refname[FLEX_ARRAY];
181};
182
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183int refs_read_raw_ref(struct ref_store *ref_store,
184 const char *refname, unsigned char *sha1,
185 struct strbuf *referent, unsigned int *type);
186
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187/*
188 * Write an error to `err` and return a nonzero value iff the same
189 * refname appears multiple times in `refnames`. `refnames` must be
190 * sorted on entry to this function.
191 */
192int ref_update_reject_duplicates(struct string_list *refnames,
193 struct strbuf *err);
194
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195/*
196 * Add a ref_update with the specified properties to transaction, and
197 * return a pointer to the new object. This function does not verify
198 * that refname is well-formed. new_sha1 and old_sha1 are only
199 * dereferenced if the REF_HAVE_NEW and REF_HAVE_OLD bits,
200 * respectively, are set in flags.
201 */
202struct ref_update *ref_transaction_add_update(
203 struct ref_transaction *transaction,
204 const char *refname, unsigned int flags,
205 const unsigned char *new_sha1,
206 const unsigned char *old_sha1,
207 const char *msg);
208
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209/*
210 * Transaction states.
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211 *
212 * OPEN: The transaction is initialized and new updates can still be
213 * added to it. An OPEN transaction can be prepared,
214 * committed, freed, or aborted (freeing and aborting an open
215 * transaction are equivalent).
216 *
217 * PREPARED: ref_transaction_prepare(), which locks all of the
218 * references involved in the update and checks that the
219 * update has no errors, has been called successfully for the
220 * transaction. A PREPARED transaction can be committed or
221 * aborted.
222 *
223 * CLOSED: The transaction is no longer active. A transaction becomes
224 * CLOSED if there is a failure while building the transaction
225 * or if a transaction is committed or aborted. A CLOSED
226 * transaction can only be freed.
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227 */
228enum ref_transaction_state {
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229 REF_TRANSACTION_OPEN = 0,
230 REF_TRANSACTION_PREPARED = 1,
231 REF_TRANSACTION_CLOSED = 2
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232};
233
234/*
235 * Data structure for holding a reference transaction, which can
236 * consist of checks and updates to multiple references, carried out
237 * as atomically as possible. This structure is opaque to callers.
238 */
239struct ref_transaction {
c0fe4e8b 240 struct ref_store *ref_store;
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241 struct ref_update **updates;
242 size_t alloc;
243 size_t nr;
244 enum ref_transaction_state state;
3bf4f561 245 void *backend_data;
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246};
247
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248/*
249 * Check for entries in extras that are within the specified
250 * directory, where dirname is a reference directory name including
251 * the trailing slash (e.g., "refs/heads/foo/"). Ignore any
252 * conflicting references that are found in skip. If there is a
253 * conflicting reference, return its name.
254 *
255 * extras and skip must be sorted lists of reference names. Either one
256 * can be NULL, signifying the empty list.
257 */
258const char *find_descendant_ref(const char *dirname,
259 const struct string_list *extras,
260 const struct string_list *skip);
261
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262/*
263 * Check whether an attempt to rename old_refname to new_refname would
264 * cause a D/F conflict with any existing reference (other than
265 * possibly old_refname). If there would be a conflict, emit an error
266 * message and return false; otherwise, return true.
267 *
268 * Note that this function is not safe against all races with other
269 * processes (though rename_ref() catches some races that might get by
270 * this check).
271 */
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272int refs_rename_ref_available(struct ref_store *refs,
273 const char *old_refname,
274 const char *new_refname);
0845122c 275
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276/* We allow "recursive" symbolic refs. Only within reason, though */
277#define SYMREF_MAXDEPTH 5
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278
279/* Include broken references in a do_for_each_ref*() iteration: */
280#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
281
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282/*
283 * Reference iterators
284 *
285 * A reference iterator encapsulates the state of an in-progress
286 * iteration over references. Create an instance of `struct
287 * ref_iterator` via one of the functions in this module.
288 *
289 * A freshly-created ref_iterator doesn't yet point at a reference. To
290 * advance the iterator, call ref_iterator_advance(). If successful,
291 * this sets the iterator's refname, oid, and flags fields to describe
292 * the next reference and returns ITER_OK. The data pointed at by
293 * refname and oid belong to the iterator; if you want to retain them
294 * after calling ref_iterator_advance() again or calling
295 * ref_iterator_abort(), you must make a copy. When the iteration has
296 * been exhausted, ref_iterator_advance() releases any resources
297 * assocated with the iteration, frees the ref_iterator object, and
298 * returns ITER_DONE. If you want to abort the iteration early, call
299 * ref_iterator_abort(), which also frees the ref_iterator object and
300 * any associated resources. If there was an internal error advancing
301 * to the next entry, ref_iterator_advance() aborts the iteration,
302 * frees the ref_iterator, and returns ITER_ERROR.
303 *
304 * The reference currently being looked at can be peeled by calling
305 * ref_iterator_peel(). This function is often faster than peel_ref(),
306 * so it should be preferred when iterating over references.
307 *
308 * Putting it all together, a typical iteration looks like this:
309 *
310 * int ok;
311 * struct ref_iterator *iter = ...;
312 *
313 * while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
314 * if (want_to_stop_iteration()) {
315 * ok = ref_iterator_abort(iter);
316 * break;
317 * }
318 *
319 * // Access information about the current reference:
320 * if (!(iter->flags & REF_ISSYMREF))
321 * printf("%s is %s\n", iter->refname, oid_to_hex(&iter->oid));
322 *
323 * // If you need to peel the reference:
324 * ref_iterator_peel(iter, &oid);
325 * }
326 *
327 * if (ok != ITER_DONE)
328 * handle_error();
329 */
330struct ref_iterator {
331 struct ref_iterator_vtable *vtable;
332 const char *refname;
333 const struct object_id *oid;
334 unsigned int flags;
335};
336
337/*
338 * Advance the iterator to the first or next item and return ITER_OK.
339 * If the iteration is exhausted, free the resources associated with
340 * the ref_iterator and return ITER_DONE. On errors, free the iterator
341 * resources and return ITER_ERROR. It is a bug to use ref_iterator or
342 * call this function again after it has returned ITER_DONE or
343 * ITER_ERROR.
344 */
345int ref_iterator_advance(struct ref_iterator *ref_iterator);
346
347/*
348 * If possible, peel the reference currently being viewed by the
349 * iterator. Return 0 on success.
350 */
351int ref_iterator_peel(struct ref_iterator *ref_iterator,
352 struct object_id *peeled);
353
354/*
355 * End the iteration before it has been exhausted, freeing the
356 * reference iterator and any associated resources and returning
357 * ITER_DONE. If the abort itself failed, return ITER_ERROR.
358 */
359int ref_iterator_abort(struct ref_iterator *ref_iterator);
360
361/*
362 * An iterator over nothing (its first ref_iterator_advance() call
363 * returns ITER_DONE).
364 */
365struct ref_iterator *empty_ref_iterator_begin(void);
366
367/*
368 * Return true iff ref_iterator is an empty_ref_iterator.
369 */
370int is_empty_ref_iterator(struct ref_iterator *ref_iterator);
371
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372/*
373 * Return an iterator that goes over each reference in `refs` for
374 * which the refname begins with prefix. If trim is non-zero, then
375 * trim that many characters off the beginning of each refname. flags
376 * can be DO_FOR_EACH_INCLUDE_BROKEN to include broken references in
377 * the iteration.
378 */
379struct ref_iterator *refs_ref_iterator_begin(
380 struct ref_store *refs,
381 const char *prefix, int trim, int flags);
382
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383/*
384 * A callback function used to instruct merge_ref_iterator how to
385 * interleave the entries from iter0 and iter1. The function should
386 * return one of the constants defined in enum iterator_selection. It
387 * must not advance either of the iterators itself.
388 *
389 * The function must be prepared to handle the case that iter0 and/or
390 * iter1 is NULL, which indicates that the corresponding sub-iterator
391 * has been exhausted. Its return value must be consistent with the
392 * current states of the iterators; e.g., it must not return
393 * ITER_SKIP_1 if iter1 has already been exhausted.
394 */
395typedef enum iterator_selection ref_iterator_select_fn(
396 struct ref_iterator *iter0, struct ref_iterator *iter1,
397 void *cb_data);
398
399/*
400 * Iterate over the entries from iter0 and iter1, with the values
401 * interleaved as directed by the select function. The iterator takes
402 * ownership of iter0 and iter1 and frees them when the iteration is
403 * over.
404 */
405struct ref_iterator *merge_ref_iterator_begin(
406 struct ref_iterator *iter0, struct ref_iterator *iter1,
407 ref_iterator_select_fn *select, void *cb_data);
408
409/*
410 * An iterator consisting of the union of the entries from front and
411 * back. If there are entries common to the two sub-iterators, use the
412 * one from front. Each iterator must iterate over its entries in
413 * strcmp() order by refname for this to work.
414 *
415 * The new iterator takes ownership of its arguments and frees them
416 * when the iteration is over. As a convenience to callers, if front
417 * or back is an empty_ref_iterator, then abort that one immediately
418 * and return the other iterator directly, without wrapping it.
419 */
420struct ref_iterator *overlay_ref_iterator_begin(
421 struct ref_iterator *front, struct ref_iterator *back);
422
423/*
424 * Wrap iter0, only letting through the references whose names start
425 * with prefix. If trim is set, set iter->refname to the name of the
426 * reference with that many characters trimmed off the front;
427 * otherwise set it to the full refname. The new iterator takes over
428 * ownership of iter0 and frees it when iteration is over. It makes
429 * its own copy of prefix.
430 *
431 * As an convenience to callers, if prefix is the empty string and
432 * trim is zero, this function returns iter0 directly, without
433 * wrapping it.
434 */
435struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
436 const char *prefix,
437 int trim);
438
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439/* Internal implementation of reference iteration: */
440
441/*
442 * Base class constructor for ref_iterators. Initialize the
443 * ref_iterator part of iter, setting its vtable pointer as specified.
444 * This is meant to be called only by the initializers of derived
445 * classes.
446 */
447void base_ref_iterator_init(struct ref_iterator *iter,
448 struct ref_iterator_vtable *vtable);
449
450/*
451 * Base class destructor for ref_iterators. Destroy the ref_iterator
452 * part of iter and shallow-free the object. This is meant to be
453 * called only by the destructors of derived classes.
454 */
455void base_ref_iterator_free(struct ref_iterator *iter);
456
457/* Virtual function declarations for ref_iterators: */
458
459typedef int ref_iterator_advance_fn(struct ref_iterator *ref_iterator);
460
461typedef int ref_iterator_peel_fn(struct ref_iterator *ref_iterator,
462 struct object_id *peeled);
463
464/*
465 * Implementations of this function should free any resources specific
466 * to the derived class, then call base_ref_iterator_free() to clean
467 * up and free the ref_iterator object.
468 */
469typedef int ref_iterator_abort_fn(struct ref_iterator *ref_iterator);
470
471struct ref_iterator_vtable {
472 ref_iterator_advance_fn *advance;
473 ref_iterator_peel_fn *peel;
474 ref_iterator_abort_fn *abort;
475};
476
93770590 477/*
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478 * current_ref_iter is a performance hack: when iterating over
479 * references using the for_each_ref*() functions, current_ref_iter is
480 * set to the reference iterator before calling the callback function.
481 * If the callback function calls peel_ref(), then peel_ref() first
482 * checks whether the reference to be peeled is the one referred to by
483 * the iterator (it usually is) and if so, asks the iterator for the
484 * peeled version of the reference if it is available. This avoids a
485 * refname lookup in a common case. current_ref_iter is set to NULL
486 * when the iteration is over.
487 */
488extern struct ref_iterator *current_ref_iter;
489
490/*
491 * The common backend for the for_each_*ref* functions. Call fn for
492 * each reference in iter. If the iterator itself ever returns
493 * ITER_ERROR, return -1. If fn ever returns a non-zero value, stop
494 * the iteration and return that value. Otherwise, return 0. In any
495 * case, free the iterator when done. This function is basically an
496 * adapter between the callback style of reference iteration and the
497 * iterator style.
498 */
499int do_for_each_ref_iterator(struct ref_iterator *iter,
500 each_ref_fn fn, void *cb_data);
2d0663b2 501
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502/*
503 * Only include per-worktree refs in a do_for_each_ref*() iteration.
504 * Normally this will be used with a files ref_store, since that's
505 * where all reference backends will presumably store their
506 * per-worktree refs.
507 */
508#define DO_FOR_EACH_PER_WORKTREE_ONLY 0x02
e1e33b72 509
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510struct ref_store;
511
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512/* refs backends */
513
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514/* ref_store_init flags */
515#define REF_STORE_READ (1 << 0)
516#define REF_STORE_WRITE (1 << 1) /* can perform update operations */
517#define REF_STORE_ODB (1 << 2) /* has access to object database */
518#define REF_STORE_MAIN (1 << 3)
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519#define REF_STORE_ALL_CAPS (REF_STORE_READ | \
520 REF_STORE_WRITE | \
521 REF_STORE_ODB | \
522 REF_STORE_MAIN)
9e7ec634 523
e1e33b72 524/*
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525 * Initialize the ref_store for the specified gitdir. These functions
526 * should call base_ref_store_init() to initialize the shared part of
527 * the ref_store and to record the ref_store for later lookup.
e1e33b72 528 */
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529typedef struct ref_store *ref_store_init_fn(const char *gitdir,
530 unsigned int flags);
e1e33b72 531
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532typedef int ref_init_db_fn(struct ref_store *refs, struct strbuf *err);
533
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534typedef int ref_transaction_prepare_fn(struct ref_store *refs,
535 struct ref_transaction *transaction,
536 struct strbuf *err);
537
538typedef int ref_transaction_finish_fn(struct ref_store *refs,
539 struct ref_transaction *transaction,
540 struct strbuf *err);
541
542typedef int ref_transaction_abort_fn(struct ref_store *refs,
543 struct ref_transaction *transaction,
544 struct strbuf *err);
545
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546typedef int ref_transaction_commit_fn(struct ref_store *refs,
547 struct ref_transaction *transaction,
548 struct strbuf *err);
549
8231527e 550typedef int pack_refs_fn(struct ref_store *ref_store, unsigned int flags);
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551typedef int peel_ref_fn(struct ref_store *ref_store,
552 const char *refname, unsigned char *sha1);
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553typedef int create_symref_fn(struct ref_store *ref_store,
554 const char *ref_target,
555 const char *refs_heads_master,
556 const char *logmsg);
64da4199 557typedef int delete_refs_fn(struct ref_store *ref_store, const char *msg,
a27dcf89 558 struct string_list *refnames, unsigned int flags);
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559typedef int rename_ref_fn(struct ref_store *ref_store,
560 const char *oldref, const char *newref,
561 const char *logmsg);
8231527e 562
1a769003 563/*
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564 * Iterate over the references in `ref_store` whose names start with
565 * `prefix`. `prefix` is matched as a literal string, without regard
566 * for path separators. If prefix is NULL or the empty string, iterate
567 * over all references in `ref_store`.
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568 */
569typedef struct ref_iterator *ref_iterator_begin_fn(
570 struct ref_store *ref_store,
571 const char *prefix, unsigned int flags);
572
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573/* reflog functions */
574
575/*
576 * Iterate over the references in the specified ref_store that have a
577 * reflog. The refs are iterated over in arbitrary order.
578 */
579typedef struct ref_iterator *reflog_iterator_begin_fn(
580 struct ref_store *ref_store);
581
582typedef int for_each_reflog_ent_fn(struct ref_store *ref_store,
583 const char *refname,
584 each_reflog_ent_fn fn,
585 void *cb_data);
586typedef int for_each_reflog_ent_reverse_fn(struct ref_store *ref_store,
587 const char *refname,
588 each_reflog_ent_fn fn,
589 void *cb_data);
590typedef int reflog_exists_fn(struct ref_store *ref_store, const char *refname);
591typedef int create_reflog_fn(struct ref_store *ref_store, const char *refname,
592 int force_create, struct strbuf *err);
593typedef int delete_reflog_fn(struct ref_store *ref_store, const char *refname);
594typedef int reflog_expire_fn(struct ref_store *ref_store,
595 const char *refname, const unsigned char *sha1,
596 unsigned int flags,
597 reflog_expiry_prepare_fn prepare_fn,
598 reflog_expiry_should_prune_fn should_prune_fn,
599 reflog_expiry_cleanup_fn cleanup_fn,
600 void *policy_cb_data);
601
cf596442 602/*
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603 * Read a reference from the specified reference store, non-recursively.
604 * Set type to describe the reference, and:
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605 *
606 * - If refname is the name of a normal reference, fill in sha1
607 * (leaving referent unchanged).
608 *
609 * - If refname is the name of a symbolic reference, write the full
610 * name of the reference to which it refers (e.g.
611 * "refs/heads/master") to referent and set the REF_ISSYMREF bit in
612 * type (leaving sha1 unchanged). The caller is responsible for
613 * validating that referent is a valid reference name.
614 *
615 * WARNING: refname might be used as part of a filename, so it is
616 * important from a security standpoint that it be safe in the sense
617 * of refname_is_safe(). Moreover, for symrefs this function sets
618 * referent to whatever the repository says, which might not be a
619 * properly-formatted or even safe reference name. NEITHER INPUT NOR
620 * OUTPUT REFERENCE NAMES ARE VALIDATED WITHIN THIS FUNCTION.
621 *
622 * Return 0 on success. If the ref doesn't exist, set errno to ENOENT
623 * and return -1. If the ref exists but is neither a symbolic ref nor
624 * a sha1, it is broken; set REF_ISBROKEN in type, set errno to
625 * EINVAL, and return -1. If there is another error reading the ref,
626 * set errno appropriately and return -1.
627 *
628 * Backend-specific flags might be set in type as well, regardless of
629 * outcome.
630 *
631 * It is OK for refname to point into referent. If so:
632 *
633 * - if the function succeeds with REF_ISSYMREF, referent will be
634 * overwritten and the memory formerly pointed to by it might be
635 * changed or even freed.
636 *
637 * - in all other cases, referent will be untouched, and therefore
638 * refname will still be valid and unchanged.
639 */
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640typedef int read_raw_ref_fn(struct ref_store *ref_store,
641 const char *refname, unsigned char *sha1,
642 struct strbuf *referent, unsigned int *type);
127b42a1 643
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644struct ref_storage_be {
645 struct ref_storage_be *next;
646 const char *name;
00eebe35 647 ref_store_init_fn *init;
6fb5acfd 648 ref_init_db_fn *init_db;
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649
650 ref_transaction_prepare_fn *transaction_prepare;
651 ref_transaction_finish_fn *transaction_finish;
652 ref_transaction_abort_fn *transaction_abort;
fc681463 653 ref_transaction_commit_fn *initial_transaction_commit;
e1e33b72 654
8231527e 655 pack_refs_fn *pack_refs;
bd427cf2 656 peel_ref_fn *peel_ref;
284689ba 657 create_symref_fn *create_symref;
a27dcf89 658 delete_refs_fn *delete_refs;
9b6b40d9 659 rename_ref_fn *rename_ref;
8231527e 660
1a769003 661 ref_iterator_begin_fn *iterator_begin;
e1e33b72 662 read_raw_ref_fn *read_raw_ref;
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663
664 reflog_iterator_begin_fn *reflog_iterator_begin;
665 for_each_reflog_ent_fn *for_each_reflog_ent;
666 for_each_reflog_ent_reverse_fn *for_each_reflog_ent_reverse;
667 reflog_exists_fn *reflog_exists;
668 create_reflog_fn *create_reflog;
669 delete_reflog_fn *delete_reflog;
670 reflog_expire_fn *reflog_expire;
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671};
672
673extern struct ref_storage_be refs_be_files;
e0cc8ac8 674extern struct ref_storage_be refs_be_packed;
3dce444f 675
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676/*
677 * A representation of the reference store for the main repository or
678 * a submodule. The ref_store instances for submodules are kept in a
679 * linked list.
680 */
681struct ref_store {
682 /* The backend describing this ref_store's storage scheme: */
683 const struct ref_storage_be *be;
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684};
685
686/*
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687 * Fill in the generic part of refs and add it to our collection of
688 * reference stores.
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689 */
690void base_ref_store_init(struct ref_store *refs,
fbfd0a29 691 const struct ref_storage_be *be);
00eebe35 692
4cb77009 693#endif /* REFS_REFS_INTERNAL_H */