Second batch for 2.19 cycle
[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/*
5ac95fee 11 * The following flags can appear in `ref_update::flags`. Their
91774afc 12 * numerical values must not conflict with those of REF_NO_DEREF and
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13 * REF_FORCE_CREATE_REFLOG, which are also stored in
14 * `ref_update::flags`.
4cb77009 15 */
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16
17/*
78fb4579 18 * The reference should be updated to new_oid.
4cb77009 19 */
5ac95fee 20#define REF_HAVE_NEW (1 << 2)
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21
22/*
5ac95fee 23 * The current reference's value should be checked to make sure that
78fb4579 24 * it agrees with old_oid.
4cb77009 25 */
5ac95fee 26#define REF_HAVE_OLD (1 << 3)
44639777 27
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28/*
29 * Return the length of time to retry acquiring a loose reference lock
30 * before giving up, in milliseconds:
31 */
32long get_files_ref_lock_timeout_ms(void);
33
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34/*
35 * Return true iff refname is minimally safe. "Safe" here means that
36 * deleting a loose reference by this name will not do any damage, for
37 * example by causing a file that is not a reference to be deleted.
38 * This function does not check that the reference name is legal; for
39 * that, use check_refname_format().
40 *
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41 * A refname that starts with "refs/" is considered safe iff it
42 * doesn't contain any "." or ".." components or consecutive '/'
43 * characters, end with '/', or (on Windows) contain any '\'
44 * characters. Names that do not start with "refs/" are considered
45 * safe iff they consist entirely of upper case characters and '_'
46 * (like "HEAD" and "MERGE_HEAD" but not "config" or "FOO/BAR").
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47 */
48int refname_is_safe(const char *refname);
49
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50/*
51 * Helper function: return true if refname, which has the specified
52 * oid and flags, can be resolved to an object in the database. If the
53 * referred-to object does not exist, emit a warning and return false.
54 */
55int ref_resolves_to_object(const char *refname,
56 const struct object_id *oid,
57 unsigned int flags);
58
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59enum peel_status {
60 /* object was peeled successfully: */
61 PEEL_PEELED = 0,
62
63 /*
64 * object cannot be peeled because the named object (or an
65 * object referred to by a tag in the peel chain), does not
66 * exist.
67 */
68 PEEL_INVALID = -1,
69
70 /* object cannot be peeled because it is not a tag: */
71 PEEL_NON_TAG = -2,
72
73 /* ref_entry contains no peeled value because it is a symref: */
74 PEEL_IS_SYMREF = -3,
75
76 /*
77 * ref_entry cannot be peeled because it is broken (i.e., the
78 * symbolic reference cannot even be resolved to an object
79 * name):
80 */
81 PEEL_BROKEN = -4
82};
83
84/*
85 * Peel the named object; i.e., if the object is a tag, resolve the
86 * tag recursively until a non-tag is found. If successful, store the
ac2ed0d7 87 * result to oid and return PEEL_PEELED. If the object is not a tag
4cb77009 88 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
78fb4579 89 * and leave oid unchanged.
4cb77009 90 */
ac2ed0d7 91enum peel_status peel_object(const struct object_id *name, struct object_id *oid);
4cb77009 92
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93/*
94 * Copy the reflog message msg to buf, which has been allocated sufficiently
95 * large, while cleaning up the whitespaces. Especially, convert LF to space,
96 * because reflog file is one line per entry.
97 */
98int copy_reflog_msg(char *buf, const char *msg);
99
4cb77009 100/**
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101 * Information needed for a single ref update. Set new_oid to the new
102 * value or to null_oid to delete the ref. To check the old value
103 * while the ref is locked, set (flags & REF_HAVE_OLD) and set old_oid
104 * to the old value, or to null_oid to ensure the ref does not exist
105 * before update.
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106 */
107struct ref_update {
108 /*
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109 * If (flags & REF_HAVE_NEW), set the reference to this value
110 * (or delete it, if `new_oid` is `null_oid`).
4cb77009 111 */
98491298 112 struct object_id new_oid;
6e30b2f6 113
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114 /*
115 * If (flags & REF_HAVE_OLD), check that the reference
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116 * previously had this value (or didn't previously exist, if
117 * `old_oid` is `null_oid`).
4cb77009 118 */
98491298 119 struct object_id old_oid;
6e30b2f6 120
4cb77009 121 /*
91774afc 122 * One or more of REF_NO_DEREF, REF_FORCE_CREATE_REFLOG,
5ac95fee 123 * REF_HAVE_NEW, REF_HAVE_OLD, or backend-specific flags.
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124 */
125 unsigned int flags;
6e30b2f6 126
7d618264 127 void *backend_data;
92b1551b 128 unsigned int type;
4cb77009 129 char *msg;
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130
131 /*
132 * If this ref_update was split off of a symref update via
133 * split_symref_update(), then this member points at that
134 * update. This is used for two purposes:
135 * 1. When reporting errors, we report the refname under which
136 * the update was originally requested.
137 * 2. When we read the old value of this reference, we
138 * propagate it back to its parent update for recording in
139 * the latter's reflog.
140 */
141 struct ref_update *parent_update;
142
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143 const char refname[FLEX_ARRAY];
144};
145
470be518 146int refs_read_raw_ref(struct ref_store *ref_store,
99afe91a 147 const char *refname, struct object_id *oid,
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148 struct strbuf *referent, unsigned int *type);
149
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150/*
151 * Write an error to `err` and return a nonzero value iff the same
152 * refname appears multiple times in `refnames`. `refnames` must be
153 * sorted on entry to this function.
154 */
155int ref_update_reject_duplicates(struct string_list *refnames,
156 struct strbuf *err);
157
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158/*
159 * Add a ref_update with the specified properties to transaction, and
160 * return a pointer to the new object. This function does not verify
78fb4579 161 * that refname is well-formed. new_oid and old_oid are only
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162 * dereferenced if the REF_HAVE_NEW and REF_HAVE_OLD bits,
163 * respectively, are set in flags.
164 */
165struct ref_update *ref_transaction_add_update(
166 struct ref_transaction *transaction,
167 const char *refname, unsigned int flags,
89f3bbdd 168 const struct object_id *new_oid,
169 const struct object_id *old_oid,
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170 const char *msg);
171
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172/*
173 * Transaction states.
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174 *
175 * OPEN: The transaction is initialized and new updates can still be
176 * added to it. An OPEN transaction can be prepared,
177 * committed, freed, or aborted (freeing and aborting an open
178 * transaction are equivalent).
179 *
180 * PREPARED: ref_transaction_prepare(), which locks all of the
181 * references involved in the update and checks that the
182 * update has no errors, has been called successfully for the
183 * transaction. A PREPARED transaction can be committed or
184 * aborted.
185 *
186 * CLOSED: The transaction is no longer active. A transaction becomes
187 * CLOSED if there is a failure while building the transaction
188 * or if a transaction is committed or aborted. A CLOSED
189 * transaction can only be freed.
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190 */
191enum ref_transaction_state {
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192 REF_TRANSACTION_OPEN = 0,
193 REF_TRANSACTION_PREPARED = 1,
194 REF_TRANSACTION_CLOSED = 2
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195};
196
197/*
198 * Data structure for holding a reference transaction, which can
199 * consist of checks and updates to multiple references, carried out
200 * as atomically as possible. This structure is opaque to callers.
201 */
202struct ref_transaction {
c0fe4e8b 203 struct ref_store *ref_store;
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204 struct ref_update **updates;
205 size_t alloc;
206 size_t nr;
207 enum ref_transaction_state state;
3bf4f561 208 void *backend_data;
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209};
210
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211/*
212 * Check for entries in extras that are within the specified
213 * directory, where dirname is a reference directory name including
214 * the trailing slash (e.g., "refs/heads/foo/"). Ignore any
215 * conflicting references that are found in skip. If there is a
216 * conflicting reference, return its name.
217 *
218 * extras and skip must be sorted lists of reference names. Either one
219 * can be NULL, signifying the empty list.
220 */
221const char *find_descendant_ref(const char *dirname,
222 const struct string_list *extras,
223 const struct string_list *skip);
224
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225/*
226 * Check whether an attempt to rename old_refname to new_refname would
227 * cause a D/F conflict with any existing reference (other than
228 * possibly old_refname). If there would be a conflict, emit an error
229 * message and return false; otherwise, return true.
230 *
231 * Note that this function is not safe against all races with other
232 * processes (though rename_ref() catches some races that might get by
233 * this check).
234 */
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235int refs_rename_ref_available(struct ref_store *refs,
236 const char *old_refname,
237 const char *new_refname);
0845122c 238
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239/* We allow "recursive" symbolic refs. Only within reason, though */
240#define SYMREF_MAXDEPTH 5
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241
242/* Include broken references in a do_for_each_ref*() iteration: */
243#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
244
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245/*
246 * Reference iterators
247 *
248 * A reference iterator encapsulates the state of an in-progress
249 * iteration over references. Create an instance of `struct
250 * ref_iterator` via one of the functions in this module.
251 *
252 * A freshly-created ref_iterator doesn't yet point at a reference. To
253 * advance the iterator, call ref_iterator_advance(). If successful,
254 * this sets the iterator's refname, oid, and flags fields to describe
255 * the next reference and returns ITER_OK. The data pointed at by
256 * refname and oid belong to the iterator; if you want to retain them
257 * after calling ref_iterator_advance() again or calling
258 * ref_iterator_abort(), you must make a copy. When the iteration has
259 * been exhausted, ref_iterator_advance() releases any resources
260 * assocated with the iteration, frees the ref_iterator object, and
261 * returns ITER_DONE. If you want to abort the iteration early, call
262 * ref_iterator_abort(), which also frees the ref_iterator object and
263 * any associated resources. If there was an internal error advancing
264 * to the next entry, ref_iterator_advance() aborts the iteration,
265 * frees the ref_iterator, and returns ITER_ERROR.
266 *
267 * The reference currently being looked at can be peeled by calling
268 * ref_iterator_peel(). This function is often faster than peel_ref(),
269 * so it should be preferred when iterating over references.
270 *
271 * Putting it all together, a typical iteration looks like this:
272 *
273 * int ok;
274 * struct ref_iterator *iter = ...;
275 *
276 * while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
277 * if (want_to_stop_iteration()) {
278 * ok = ref_iterator_abort(iter);
279 * break;
280 * }
281 *
282 * // Access information about the current reference:
283 * if (!(iter->flags & REF_ISSYMREF))
284 * printf("%s is %s\n", iter->refname, oid_to_hex(&iter->oid));
285 *
286 * // If you need to peel the reference:
287 * ref_iterator_peel(iter, &oid);
288 * }
289 *
290 * if (ok != ITER_DONE)
291 * handle_error();
292 */
293struct ref_iterator {
294 struct ref_iterator_vtable *vtable;
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295
296 /*
297 * Does this `ref_iterator` iterate over references in order
298 * by refname?
299 */
300 unsigned int ordered : 1;
301
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302 const char *refname;
303 const struct object_id *oid;
304 unsigned int flags;
305};
306
307/*
308 * Advance the iterator to the first or next item and return ITER_OK.
309 * If the iteration is exhausted, free the resources associated with
310 * the ref_iterator and return ITER_DONE. On errors, free the iterator
311 * resources and return ITER_ERROR. It is a bug to use ref_iterator or
312 * call this function again after it has returned ITER_DONE or
313 * ITER_ERROR.
314 */
315int ref_iterator_advance(struct ref_iterator *ref_iterator);
316
317/*
318 * If possible, peel the reference currently being viewed by the
319 * iterator. Return 0 on success.
320 */
321int ref_iterator_peel(struct ref_iterator *ref_iterator,
322 struct object_id *peeled);
323
324/*
325 * End the iteration before it has been exhausted, freeing the
326 * reference iterator and any associated resources and returning
327 * ITER_DONE. If the abort itself failed, return ITER_ERROR.
328 */
329int ref_iterator_abort(struct ref_iterator *ref_iterator);
330
331/*
332 * An iterator over nothing (its first ref_iterator_advance() call
333 * returns ITER_DONE).
334 */
335struct ref_iterator *empty_ref_iterator_begin(void);
336
337/*
338 * Return true iff ref_iterator is an empty_ref_iterator.
339 */
340int is_empty_ref_iterator(struct ref_iterator *ref_iterator);
341
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342/*
343 * Return an iterator that goes over each reference in `refs` for
344 * which the refname begins with prefix. If trim is non-zero, then
345 * trim that many characters off the beginning of each refname. flags
346 * can be DO_FOR_EACH_INCLUDE_BROKEN to include broken references in
8738a8a4 347 * the iteration. The output is ordered by refname.
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348 */
349struct ref_iterator *refs_ref_iterator_begin(
350 struct ref_store *refs,
351 const char *prefix, int trim, int flags);
352
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353/*
354 * A callback function used to instruct merge_ref_iterator how to
355 * interleave the entries from iter0 and iter1. The function should
356 * return one of the constants defined in enum iterator_selection. It
357 * must not advance either of the iterators itself.
358 *
359 * The function must be prepared to handle the case that iter0 and/or
360 * iter1 is NULL, which indicates that the corresponding sub-iterator
361 * has been exhausted. Its return value must be consistent with the
362 * current states of the iterators; e.g., it must not return
363 * ITER_SKIP_1 if iter1 has already been exhausted.
364 */
365typedef enum iterator_selection ref_iterator_select_fn(
366 struct ref_iterator *iter0, struct ref_iterator *iter1,
367 void *cb_data);
368
369/*
370 * Iterate over the entries from iter0 and iter1, with the values
371 * interleaved as directed by the select function. The iterator takes
372 * ownership of iter0 and iter1 and frees them when the iteration is
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373 * over. A derived class should set `ordered` to 1 or 0 based on
374 * whether it generates its output in order by reference name.
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375 */
376struct ref_iterator *merge_ref_iterator_begin(
8738a8a4 377 int ordered,
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378 struct ref_iterator *iter0, struct ref_iterator *iter1,
379 ref_iterator_select_fn *select, void *cb_data);
380
381/*
382 * An iterator consisting of the union of the entries from front and
383 * back. If there are entries common to the two sub-iterators, use the
384 * one from front. Each iterator must iterate over its entries in
385 * strcmp() order by refname for this to work.
386 *
387 * The new iterator takes ownership of its arguments and frees them
388 * when the iteration is over. As a convenience to callers, if front
389 * or back is an empty_ref_iterator, then abort that one immediately
390 * and return the other iterator directly, without wrapping it.
391 */
392struct ref_iterator *overlay_ref_iterator_begin(
393 struct ref_iterator *front, struct ref_iterator *back);
394
395/*
396 * Wrap iter0, only letting through the references whose names start
397 * with prefix. If trim is set, set iter->refname to the name of the
398 * reference with that many characters trimmed off the front;
399 * otherwise set it to the full refname. The new iterator takes over
400 * ownership of iter0 and frees it when iteration is over. It makes
401 * its own copy of prefix.
402 *
403 * As an convenience to callers, if prefix is the empty string and
404 * trim is zero, this function returns iter0 directly, without
405 * wrapping it.
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406 *
407 * The resulting ref_iterator is ordered if iter0 is.
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408 */
409struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
410 const char *prefix,
411 int trim);
412
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413/* Internal implementation of reference iteration: */
414
415/*
416 * Base class constructor for ref_iterators. Initialize the
417 * ref_iterator part of iter, setting its vtable pointer as specified.
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418 * `ordered` should be set to 1 if the iterator will iterate over
419 * references in order by refname; otherwise it should be set to 0.
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420 * This is meant to be called only by the initializers of derived
421 * classes.
422 */
423void base_ref_iterator_init(struct ref_iterator *iter,
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424 struct ref_iterator_vtable *vtable,
425 int ordered);
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426
427/*
428 * Base class destructor for ref_iterators. Destroy the ref_iterator
429 * part of iter and shallow-free the object. This is meant to be
430 * called only by the destructors of derived classes.
431 */
432void base_ref_iterator_free(struct ref_iterator *iter);
433
434/* Virtual function declarations for ref_iterators: */
435
436typedef int ref_iterator_advance_fn(struct ref_iterator *ref_iterator);
437
438typedef int ref_iterator_peel_fn(struct ref_iterator *ref_iterator,
439 struct object_id *peeled);
440
441/*
442 * Implementations of this function should free any resources specific
443 * to the derived class, then call base_ref_iterator_free() to clean
444 * up and free the ref_iterator object.
445 */
446typedef int ref_iterator_abort_fn(struct ref_iterator *ref_iterator);
447
448struct ref_iterator_vtable {
449 ref_iterator_advance_fn *advance;
450 ref_iterator_peel_fn *peel;
451 ref_iterator_abort_fn *abort;
452};
453
93770590 454/*
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455 * current_ref_iter is a performance hack: when iterating over
456 * references using the for_each_ref*() functions, current_ref_iter is
457 * set to the reference iterator before calling the callback function.
458 * If the callback function calls peel_ref(), then peel_ref() first
459 * checks whether the reference to be peeled is the one referred to by
460 * the iterator (it usually is) and if so, asks the iterator for the
461 * peeled version of the reference if it is available. This avoids a
462 * refname lookup in a common case. current_ref_iter is set to NULL
463 * when the iteration is over.
464 */
465extern struct ref_iterator *current_ref_iter;
466
467/*
468 * The common backend for the for_each_*ref* functions. Call fn for
469 * each reference in iter. If the iterator itself ever returns
470 * ITER_ERROR, return -1. If fn ever returns a non-zero value, stop
471 * the iteration and return that value. Otherwise, return 0. In any
472 * case, free the iterator when done. This function is basically an
473 * adapter between the callback style of reference iteration and the
474 * iterator style.
475 */
476int do_for_each_ref_iterator(struct ref_iterator *iter,
477 each_ref_fn fn, void *cb_data);
2d0663b2 478
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479/*
480 * Only include per-worktree refs in a do_for_each_ref*() iteration.
481 * Normally this will be used with a files ref_store, since that's
482 * where all reference backends will presumably store their
483 * per-worktree refs.
484 */
485#define DO_FOR_EACH_PER_WORKTREE_ONLY 0x02
e1e33b72 486
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487struct ref_store;
488
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489/* refs backends */
490
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491/* ref_store_init flags */
492#define REF_STORE_READ (1 << 0)
493#define REF_STORE_WRITE (1 << 1) /* can perform update operations */
494#define REF_STORE_ODB (1 << 2) /* has access to object database */
495#define REF_STORE_MAIN (1 << 3)
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496#define REF_STORE_ALL_CAPS (REF_STORE_READ | \
497 REF_STORE_WRITE | \
498 REF_STORE_ODB | \
499 REF_STORE_MAIN)
9e7ec634 500
e1e33b72 501/*
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502 * Initialize the ref_store for the specified gitdir. These functions
503 * should call base_ref_store_init() to initialize the shared part of
504 * the ref_store and to record the ref_store for later lookup.
e1e33b72 505 */
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506typedef struct ref_store *ref_store_init_fn(const char *gitdir,
507 unsigned int flags);
e1e33b72 508
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509typedef int ref_init_db_fn(struct ref_store *refs, struct strbuf *err);
510
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511typedef int ref_transaction_prepare_fn(struct ref_store *refs,
512 struct ref_transaction *transaction,
513 struct strbuf *err);
514
515typedef int ref_transaction_finish_fn(struct ref_store *refs,
516 struct ref_transaction *transaction,
517 struct strbuf *err);
518
519typedef int ref_transaction_abort_fn(struct ref_store *refs,
520 struct ref_transaction *transaction,
521 struct strbuf *err);
522
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523typedef int ref_transaction_commit_fn(struct ref_store *refs,
524 struct ref_transaction *transaction,
525 struct strbuf *err);
526
8231527e 527typedef int pack_refs_fn(struct ref_store *ref_store, unsigned int flags);
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528typedef int create_symref_fn(struct ref_store *ref_store,
529 const char *ref_target,
530 const char *refs_heads_master,
531 const char *logmsg);
64da4199 532typedef int delete_refs_fn(struct ref_store *ref_store, const char *msg,
a27dcf89 533 struct string_list *refnames, unsigned int flags);
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DT
534typedef int rename_ref_fn(struct ref_store *ref_store,
535 const char *oldref, const char *newref,
536 const char *logmsg);
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SD
537typedef int copy_ref_fn(struct ref_store *ref_store,
538 const char *oldref, const char *newref,
539 const char *logmsg);
8231527e 540
1a769003 541/*
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542 * Iterate over the references in `ref_store` whose names start with
543 * `prefix`. `prefix` is matched as a literal string, without regard
544 * for path separators. If prefix is NULL or the empty string, iterate
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545 * over all references in `ref_store`. The output is ordered by
546 * refname.
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547 */
548typedef struct ref_iterator *ref_iterator_begin_fn(
549 struct ref_store *ref_store,
550 const char *prefix, unsigned int flags);
551
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DT
552/* reflog functions */
553
554/*
555 * Iterate over the references in the specified ref_store that have a
556 * reflog. The refs are iterated over in arbitrary order.
557 */
558typedef struct ref_iterator *reflog_iterator_begin_fn(
559 struct ref_store *ref_store);
560
561typedef int for_each_reflog_ent_fn(struct ref_store *ref_store,
562 const char *refname,
563 each_reflog_ent_fn fn,
564 void *cb_data);
565typedef int for_each_reflog_ent_reverse_fn(struct ref_store *ref_store,
566 const char *refname,
567 each_reflog_ent_fn fn,
568 void *cb_data);
569typedef int reflog_exists_fn(struct ref_store *ref_store, const char *refname);
570typedef int create_reflog_fn(struct ref_store *ref_store, const char *refname,
571 int force_create, struct strbuf *err);
572typedef int delete_reflog_fn(struct ref_store *ref_store, const char *refname);
573typedef int reflog_expire_fn(struct ref_store *ref_store,
0155f710 574 const char *refname, const struct object_id *oid,
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DT
575 unsigned int flags,
576 reflog_expiry_prepare_fn prepare_fn,
577 reflog_expiry_should_prune_fn should_prune_fn,
578 reflog_expiry_cleanup_fn cleanup_fn,
579 void *policy_cb_data);
580
cf596442 581/*
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582 * Read a reference from the specified reference store, non-recursively.
583 * Set type to describe the reference, and:
cf596442 584 *
99afe91a 585 * - If refname is the name of a normal reference, fill in oid
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586 * (leaving referent unchanged).
587 *
588 * - If refname is the name of a symbolic reference, write the full
589 * name of the reference to which it refers (e.g.
590 * "refs/heads/master") to referent and set the REF_ISSYMREF bit in
99afe91a 591 * type (leaving oid unchanged). The caller is responsible for
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592 * validating that referent is a valid reference name.
593 *
594 * WARNING: refname might be used as part of a filename, so it is
595 * important from a security standpoint that it be safe in the sense
596 * of refname_is_safe(). Moreover, for symrefs this function sets
597 * referent to whatever the repository says, which might not be a
598 * properly-formatted or even safe reference name. NEITHER INPUT NOR
599 * OUTPUT REFERENCE NAMES ARE VALIDATED WITHIN THIS FUNCTION.
600 *
601 * Return 0 on success. If the ref doesn't exist, set errno to ENOENT
602 * and return -1. If the ref exists but is neither a symbolic ref nor
99afe91a 603 * an object ID, it is broken; set REF_ISBROKEN in type, set errno to
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604 * EINVAL, and return -1. If there is another error reading the ref,
605 * set errno appropriately and return -1.
606 *
607 * Backend-specific flags might be set in type as well, regardless of
608 * outcome.
609 *
610 * It is OK for refname to point into referent. If so:
611 *
612 * - if the function succeeds with REF_ISSYMREF, referent will be
613 * overwritten and the memory formerly pointed to by it might be
614 * changed or even freed.
615 *
616 * - in all other cases, referent will be untouched, and therefore
617 * refname will still be valid and unchanged.
618 */
e1e33b72 619typedef int read_raw_ref_fn(struct ref_store *ref_store,
99afe91a 620 const char *refname, struct object_id *oid,
e1e33b72 621 struct strbuf *referent, unsigned int *type);
127b42a1 622
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623struct ref_storage_be {
624 struct ref_storage_be *next;
625 const char *name;
00eebe35 626 ref_store_init_fn *init;
6fb5acfd 627 ref_init_db_fn *init_db;
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628
629 ref_transaction_prepare_fn *transaction_prepare;
630 ref_transaction_finish_fn *transaction_finish;
631 ref_transaction_abort_fn *transaction_abort;
fc681463 632 ref_transaction_commit_fn *initial_transaction_commit;
e1e33b72 633
8231527e 634 pack_refs_fn *pack_refs;
284689ba 635 create_symref_fn *create_symref;
a27dcf89 636 delete_refs_fn *delete_refs;
9b6b40d9 637 rename_ref_fn *rename_ref;
52d59cc6 638 copy_ref_fn *copy_ref;
8231527e 639
1a769003 640 ref_iterator_begin_fn *iterator_begin;
e1e33b72 641 read_raw_ref_fn *read_raw_ref;
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642
643 reflog_iterator_begin_fn *reflog_iterator_begin;
644 for_each_reflog_ent_fn *for_each_reflog_ent;
645 for_each_reflog_ent_reverse_fn *for_each_reflog_ent_reverse;
646 reflog_exists_fn *reflog_exists;
647 create_reflog_fn *create_reflog;
648 delete_reflog_fn *delete_reflog;
649 reflog_expire_fn *reflog_expire;
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650};
651
652extern struct ref_storage_be refs_be_files;
e0cc8ac8 653extern struct ref_storage_be refs_be_packed;
3dce444f 654
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655/*
656 * A representation of the reference store for the main repository or
657 * a submodule. The ref_store instances for submodules are kept in a
658 * linked list.
659 */
660struct ref_store {
661 /* The backend describing this ref_store's storage scheme: */
662 const struct ref_storage_be *be;
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663};
664
665/*
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666 * Fill in the generic part of refs and add it to our collection of
667 * reference stores.
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668 */
669void base_ref_store_init(struct ref_store *refs,
fbfd0a29 670 const struct ref_storage_be *be);
00eebe35 671
4cb77009 672#endif /* REFS_REFS_INTERNAL_H */