refs: convert peel_object to struct object_id
[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
ac2ed0d7 123 * result to oid and return PEEL_PEELED. If the object is not a tag
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124 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
125 * and leave sha1 unchanged.
126 */
ac2ed0d7 127enum peel_status peel_object(const struct object_id *name, struct object_id *oid);
4cb77009 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,
89f3bbdd 205 const struct object_id *new_oid,
206 const struct object_id *old_oid,
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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;
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332
333 /*
334 * Does this `ref_iterator` iterate over references in order
335 * by refname?
336 */
337 unsigned int ordered : 1;
338
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339 const char *refname;
340 const struct object_id *oid;
341 unsigned int flags;
342};
343
344/*
345 * Advance the iterator to the first or next item and return ITER_OK.
346 * If the iteration is exhausted, free the resources associated with
347 * the ref_iterator and return ITER_DONE. On errors, free the iterator
348 * resources and return ITER_ERROR. It is a bug to use ref_iterator or
349 * call this function again after it has returned ITER_DONE or
350 * ITER_ERROR.
351 */
352int ref_iterator_advance(struct ref_iterator *ref_iterator);
353
354/*
355 * If possible, peel the reference currently being viewed by the
356 * iterator. Return 0 on success.
357 */
358int ref_iterator_peel(struct ref_iterator *ref_iterator,
359 struct object_id *peeled);
360
361/*
362 * End the iteration before it has been exhausted, freeing the
363 * reference iterator and any associated resources and returning
364 * ITER_DONE. If the abort itself failed, return ITER_ERROR.
365 */
366int ref_iterator_abort(struct ref_iterator *ref_iterator);
367
368/*
369 * An iterator over nothing (its first ref_iterator_advance() call
370 * returns ITER_DONE).
371 */
372struct ref_iterator *empty_ref_iterator_begin(void);
373
374/*
375 * Return true iff ref_iterator is an empty_ref_iterator.
376 */
377int is_empty_ref_iterator(struct ref_iterator *ref_iterator);
378
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379/*
380 * Return an iterator that goes over each reference in `refs` for
381 * which the refname begins with prefix. If trim is non-zero, then
382 * trim that many characters off the beginning of each refname. flags
383 * can be DO_FOR_EACH_INCLUDE_BROKEN to include broken references in
8738a8a4 384 * the iteration. The output is ordered by refname.
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385 */
386struct ref_iterator *refs_ref_iterator_begin(
387 struct ref_store *refs,
388 const char *prefix, int trim, int flags);
389
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390/*
391 * A callback function used to instruct merge_ref_iterator how to
392 * interleave the entries from iter0 and iter1. The function should
393 * return one of the constants defined in enum iterator_selection. It
394 * must not advance either of the iterators itself.
395 *
396 * The function must be prepared to handle the case that iter0 and/or
397 * iter1 is NULL, which indicates that the corresponding sub-iterator
398 * has been exhausted. Its return value must be consistent with the
399 * current states of the iterators; e.g., it must not return
400 * ITER_SKIP_1 if iter1 has already been exhausted.
401 */
402typedef enum iterator_selection ref_iterator_select_fn(
403 struct ref_iterator *iter0, struct ref_iterator *iter1,
404 void *cb_data);
405
406/*
407 * Iterate over the entries from iter0 and iter1, with the values
408 * interleaved as directed by the select function. The iterator takes
409 * ownership of iter0 and iter1 and frees them when the iteration is
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410 * over. A derived class should set `ordered` to 1 or 0 based on
411 * whether it generates its output in order by reference name.
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412 */
413struct ref_iterator *merge_ref_iterator_begin(
8738a8a4 414 int ordered,
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415 struct ref_iterator *iter0, struct ref_iterator *iter1,
416 ref_iterator_select_fn *select, void *cb_data);
417
418/*
419 * An iterator consisting of the union of the entries from front and
420 * back. If there are entries common to the two sub-iterators, use the
421 * one from front. Each iterator must iterate over its entries in
422 * strcmp() order by refname for this to work.
423 *
424 * The new iterator takes ownership of its arguments and frees them
425 * when the iteration is over. As a convenience to callers, if front
426 * or back is an empty_ref_iterator, then abort that one immediately
427 * and return the other iterator directly, without wrapping it.
428 */
429struct ref_iterator *overlay_ref_iterator_begin(
430 struct ref_iterator *front, struct ref_iterator *back);
431
432/*
433 * Wrap iter0, only letting through the references whose names start
434 * with prefix. If trim is set, set iter->refname to the name of the
435 * reference with that many characters trimmed off the front;
436 * otherwise set it to the full refname. The new iterator takes over
437 * ownership of iter0 and frees it when iteration is over. It makes
438 * its own copy of prefix.
439 *
440 * As an convenience to callers, if prefix is the empty string and
441 * trim is zero, this function returns iter0 directly, without
442 * wrapping it.
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443 *
444 * The resulting ref_iterator is ordered if iter0 is.
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445 */
446struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
447 const char *prefix,
448 int trim);
449
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450/* Internal implementation of reference iteration: */
451
452/*
453 * Base class constructor for ref_iterators. Initialize the
454 * ref_iterator part of iter, setting its vtable pointer as specified.
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455 * `ordered` should be set to 1 if the iterator will iterate over
456 * references in order by refname; otherwise it should be set to 0.
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457 * This is meant to be called only by the initializers of derived
458 * classes.
459 */
460void base_ref_iterator_init(struct ref_iterator *iter,
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461 struct ref_iterator_vtable *vtable,
462 int ordered);
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463
464/*
465 * Base class destructor for ref_iterators. Destroy the ref_iterator
466 * part of iter and shallow-free the object. This is meant to be
467 * called only by the destructors of derived classes.
468 */
469void base_ref_iterator_free(struct ref_iterator *iter);
470
471/* Virtual function declarations for ref_iterators: */
472
473typedef int ref_iterator_advance_fn(struct ref_iterator *ref_iterator);
474
475typedef int ref_iterator_peel_fn(struct ref_iterator *ref_iterator,
476 struct object_id *peeled);
477
478/*
479 * Implementations of this function should free any resources specific
480 * to the derived class, then call base_ref_iterator_free() to clean
481 * up and free the ref_iterator object.
482 */
483typedef int ref_iterator_abort_fn(struct ref_iterator *ref_iterator);
484
485struct ref_iterator_vtable {
486 ref_iterator_advance_fn *advance;
487 ref_iterator_peel_fn *peel;
488 ref_iterator_abort_fn *abort;
489};
490
93770590 491/*
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492 * current_ref_iter is a performance hack: when iterating over
493 * references using the for_each_ref*() functions, current_ref_iter is
494 * set to the reference iterator before calling the callback function.
495 * If the callback function calls peel_ref(), then peel_ref() first
496 * checks whether the reference to be peeled is the one referred to by
497 * the iterator (it usually is) and if so, asks the iterator for the
498 * peeled version of the reference if it is available. This avoids a
499 * refname lookup in a common case. current_ref_iter is set to NULL
500 * when the iteration is over.
501 */
502extern struct ref_iterator *current_ref_iter;
503
504/*
505 * The common backend for the for_each_*ref* functions. Call fn for
506 * each reference in iter. If the iterator itself ever returns
507 * ITER_ERROR, return -1. If fn ever returns a non-zero value, stop
508 * the iteration and return that value. Otherwise, return 0. In any
509 * case, free the iterator when done. This function is basically an
510 * adapter between the callback style of reference iteration and the
511 * iterator style.
512 */
513int do_for_each_ref_iterator(struct ref_iterator *iter,
514 each_ref_fn fn, void *cb_data);
2d0663b2 515
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516/*
517 * Only include per-worktree refs in a do_for_each_ref*() iteration.
518 * Normally this will be used with a files ref_store, since that's
519 * where all reference backends will presumably store their
520 * per-worktree refs.
521 */
522#define DO_FOR_EACH_PER_WORKTREE_ONLY 0x02
e1e33b72 523
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524struct ref_store;
525
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526/* refs backends */
527
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528/* ref_store_init flags */
529#define REF_STORE_READ (1 << 0)
530#define REF_STORE_WRITE (1 << 1) /* can perform update operations */
531#define REF_STORE_ODB (1 << 2) /* has access to object database */
532#define REF_STORE_MAIN (1 << 3)
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533#define REF_STORE_ALL_CAPS (REF_STORE_READ | \
534 REF_STORE_WRITE | \
535 REF_STORE_ODB | \
536 REF_STORE_MAIN)
9e7ec634 537
e1e33b72 538/*
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539 * Initialize the ref_store for the specified gitdir. These functions
540 * should call base_ref_store_init() to initialize the shared part of
541 * the ref_store and to record the ref_store for later lookup.
e1e33b72 542 */
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543typedef struct ref_store *ref_store_init_fn(const char *gitdir,
544 unsigned int flags);
e1e33b72 545
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546typedef int ref_init_db_fn(struct ref_store *refs, struct strbuf *err);
547
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548typedef int ref_transaction_prepare_fn(struct ref_store *refs,
549 struct ref_transaction *transaction,
550 struct strbuf *err);
551
552typedef int ref_transaction_finish_fn(struct ref_store *refs,
553 struct ref_transaction *transaction,
554 struct strbuf *err);
555
556typedef int ref_transaction_abort_fn(struct ref_store *refs,
557 struct ref_transaction *transaction,
558 struct strbuf *err);
559
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560typedef int ref_transaction_commit_fn(struct ref_store *refs,
561 struct ref_transaction *transaction,
562 struct strbuf *err);
563
8231527e 564typedef int pack_refs_fn(struct ref_store *ref_store, unsigned int flags);
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565typedef int create_symref_fn(struct ref_store *ref_store,
566 const char *ref_target,
567 const char *refs_heads_master,
568 const char *logmsg);
64da4199 569typedef int delete_refs_fn(struct ref_store *ref_store, const char *msg,
a27dcf89 570 struct string_list *refnames, unsigned int flags);
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571typedef int rename_ref_fn(struct ref_store *ref_store,
572 const char *oldref, const char *newref,
573 const char *logmsg);
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574typedef int copy_ref_fn(struct ref_store *ref_store,
575 const char *oldref, const char *newref,
576 const char *logmsg);
8231527e 577
1a769003 578/*
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579 * Iterate over the references in `ref_store` whose names start with
580 * `prefix`. `prefix` is matched as a literal string, without regard
581 * for path separators. If prefix is NULL or the empty string, iterate
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582 * over all references in `ref_store`. The output is ordered by
583 * refname.
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584 */
585typedef struct ref_iterator *ref_iterator_begin_fn(
586 struct ref_store *ref_store,
587 const char *prefix, unsigned int flags);
588
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589/* reflog functions */
590
591/*
592 * Iterate over the references in the specified ref_store that have a
593 * reflog. The refs are iterated over in arbitrary order.
594 */
595typedef struct ref_iterator *reflog_iterator_begin_fn(
596 struct ref_store *ref_store);
597
598typedef int for_each_reflog_ent_fn(struct ref_store *ref_store,
599 const char *refname,
600 each_reflog_ent_fn fn,
601 void *cb_data);
602typedef int for_each_reflog_ent_reverse_fn(struct ref_store *ref_store,
603 const char *refname,
604 each_reflog_ent_fn fn,
605 void *cb_data);
606typedef int reflog_exists_fn(struct ref_store *ref_store, const char *refname);
607typedef int create_reflog_fn(struct ref_store *ref_store, const char *refname,
608 int force_create, struct strbuf *err);
609typedef int delete_reflog_fn(struct ref_store *ref_store, const char *refname);
610typedef int reflog_expire_fn(struct ref_store *ref_store,
0155f710 611 const char *refname, const struct object_id *oid,
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612 unsigned int flags,
613 reflog_expiry_prepare_fn prepare_fn,
614 reflog_expiry_should_prune_fn should_prune_fn,
615 reflog_expiry_cleanup_fn cleanup_fn,
616 void *policy_cb_data);
617
cf596442 618/*
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619 * Read a reference from the specified reference store, non-recursively.
620 * Set type to describe the reference, and:
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MH
621 *
622 * - If refname is the name of a normal reference, fill in sha1
623 * (leaving referent unchanged).
624 *
625 * - If refname is the name of a symbolic reference, write the full
626 * name of the reference to which it refers (e.g.
627 * "refs/heads/master") to referent and set the REF_ISSYMREF bit in
628 * type (leaving sha1 unchanged). The caller is responsible for
629 * validating that referent is a valid reference name.
630 *
631 * WARNING: refname might be used as part of a filename, so it is
632 * important from a security standpoint that it be safe in the sense
633 * of refname_is_safe(). Moreover, for symrefs this function sets
634 * referent to whatever the repository says, which might not be a
635 * properly-formatted or even safe reference name. NEITHER INPUT NOR
636 * OUTPUT REFERENCE NAMES ARE VALIDATED WITHIN THIS FUNCTION.
637 *
638 * Return 0 on success. If the ref doesn't exist, set errno to ENOENT
639 * and return -1. If the ref exists but is neither a symbolic ref nor
640 * a sha1, it is broken; set REF_ISBROKEN in type, set errno to
641 * EINVAL, and return -1. If there is another error reading the ref,
642 * set errno appropriately and return -1.
643 *
644 * Backend-specific flags might be set in type as well, regardless of
645 * outcome.
646 *
647 * It is OK for refname to point into referent. If so:
648 *
649 * - if the function succeeds with REF_ISSYMREF, referent will be
650 * overwritten and the memory formerly pointed to by it might be
651 * changed or even freed.
652 *
653 * - in all other cases, referent will be untouched, and therefore
654 * refname will still be valid and unchanged.
655 */
e1e33b72
MH
656typedef int read_raw_ref_fn(struct ref_store *ref_store,
657 const char *refname, unsigned char *sha1,
658 struct strbuf *referent, unsigned int *type);
127b42a1 659
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RS
660struct ref_storage_be {
661 struct ref_storage_be *next;
662 const char *name;
00eebe35 663 ref_store_init_fn *init;
6fb5acfd 664 ref_init_db_fn *init_db;
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MH
665
666 ref_transaction_prepare_fn *transaction_prepare;
667 ref_transaction_finish_fn *transaction_finish;
668 ref_transaction_abort_fn *transaction_abort;
fc681463 669 ref_transaction_commit_fn *initial_transaction_commit;
e1e33b72 670
8231527e 671 pack_refs_fn *pack_refs;
284689ba 672 create_symref_fn *create_symref;
a27dcf89 673 delete_refs_fn *delete_refs;
9b6b40d9 674 rename_ref_fn *rename_ref;
52d59cc6 675 copy_ref_fn *copy_ref;
8231527e 676
1a769003 677 ref_iterator_begin_fn *iterator_begin;
e1e33b72 678 read_raw_ref_fn *read_raw_ref;
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DT
679
680 reflog_iterator_begin_fn *reflog_iterator_begin;
681 for_each_reflog_ent_fn *for_each_reflog_ent;
682 for_each_reflog_ent_reverse_fn *for_each_reflog_ent_reverse;
683 reflog_exists_fn *reflog_exists;
684 create_reflog_fn *create_reflog;
685 delete_reflog_fn *delete_reflog;
686 reflog_expire_fn *reflog_expire;
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RS
687};
688
689extern struct ref_storage_be refs_be_files;
e0cc8ac8 690extern struct ref_storage_be refs_be_packed;
3dce444f 691
00eebe35
MH
692/*
693 * A representation of the reference store for the main repository or
694 * a submodule. The ref_store instances for submodules are kept in a
695 * linked list.
696 */
697struct ref_store {
698 /* The backend describing this ref_store's storage scheme: */
699 const struct ref_storage_be *be;
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700};
701
702/*
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703 * Fill in the generic part of refs and add it to our collection of
704 * reference stores.
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705 */
706void base_ref_store_init(struct ref_store *refs,
fbfd0a29 707 const struct ref_storage_be *be);
00eebe35 708
4cb77009 709#endif /* REFS_REFS_INTERNAL_H */