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