Merge branch 'jk/core-use-replace-refs'
[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
13f925f3 4#include "iterator.h"
91c2f204 5
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6/*
7 * Data structures and functions for the internal use of the refs
8 * module. Code outside of the refs module should use only the public
9 * functions defined in "refs.h", and should *not* include this file.
10 */
11
12/*
5ac95fee 13 * The following flags can appear in `ref_update::flags`. Their
91774afc 14 * numerical values must not conflict with those of REF_NO_DEREF and
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15 * REF_FORCE_CREATE_REFLOG, which are also stored in
16 * `ref_update::flags`.
4cb77009 17 */
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18
19/*
78fb4579 20 * The reference should be updated to new_oid.
4cb77009 21 */
5ac95fee 22#define REF_HAVE_NEW (1 << 2)
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23
24/*
5ac95fee 25 * The current reference's value should be checked to make sure that
78fb4579 26 * it agrees with old_oid.
4cb77009 27 */
5ac95fee 28#define REF_HAVE_OLD (1 << 3)
44639777 29
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30/*
31 * Return the length of time to retry acquiring a loose reference lock
32 * before giving up, in milliseconds:
33 */
34long get_files_ref_lock_timeout_ms(void);
35
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36/*
37 * Return true iff refname is minimally safe. "Safe" here means that
38 * deleting a loose reference by this name will not do any damage, for
39 * example by causing a file that is not a reference to be deleted.
40 * This function does not check that the reference name is legal; for
41 * that, use check_refname_format().
42 *
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43 * A refname that starts with "refs/" is considered safe iff it
44 * doesn't contain any "." or ".." components or consecutive '/'
45 * characters, end with '/', or (on Windows) contain any '\'
46 * characters. Names that do not start with "refs/" are considered
47 * safe iff they consist entirely of upper case characters and '_'
48 * (like "HEAD" and "MERGE_HEAD" but not "config" or "FOO/BAR").
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49 */
50int refname_is_safe(const char *refname);
51
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52/*
53 * Helper function: return true if refname, which has the specified
54 * oid and flags, can be resolved to an object in the database. If the
55 * referred-to object does not exist, emit a warning and return false.
56 */
57int ref_resolves_to_object(const char *refname,
58 const struct object_id *oid,
59 unsigned int flags);
60
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61enum peel_status {
62 /* object was peeled successfully: */
63 PEEL_PEELED = 0,
64
65 /*
66 * object cannot be peeled because the named object (or an
67 * object referred to by a tag in the peel chain), does not
68 * exist.
69 */
70 PEEL_INVALID = -1,
71
72 /* object cannot be peeled because it is not a tag: */
73 PEEL_NON_TAG = -2,
74
75 /* ref_entry contains no peeled value because it is a symref: */
76 PEEL_IS_SYMREF = -3,
77
78 /*
79 * ref_entry cannot be peeled because it is broken (i.e., the
80 * symbolic reference cannot even be resolved to an object
81 * name):
82 */
83 PEEL_BROKEN = -4
84};
85
86/*
87 * Peel the named object; i.e., if the object is a tag, resolve the
88 * tag recursively until a non-tag is found. If successful, store the
ac2ed0d7 89 * result to oid and return PEEL_PEELED. If the object is not a tag
4cb77009 90 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
78fb4579 91 * and leave oid unchanged.
4cb77009 92 */
ac2ed0d7 93enum peel_status peel_object(const struct object_id *name, struct object_id *oid);
4cb77009 94
4cb77009 95/*
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96 * Copy the reflog message msg to sb while cleaning up the whitespaces.
97 * Especially, convert LF to space, because reflog file is one line per entry.
4cb77009 98 */
80a6c207 99void copy_reflog_msg(struct strbuf *sb, const char *msg);
4cb77009 100
4cb77009 101/**
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102 * Information needed for a single ref update. Set new_oid to the new
103 * value or to null_oid to delete the ref. To check the old value
104 * while the ref is locked, set (flags & REF_HAVE_OLD) and set old_oid
105 * to the old value, or to null_oid to ensure the ref does not exist
106 * before update.
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107 */
108struct ref_update {
109 /*
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110 * If (flags & REF_HAVE_NEW), set the reference to this value
111 * (or delete it, if `new_oid` is `null_oid`).
4cb77009 112 */
98491298 113 struct object_id new_oid;
6e30b2f6 114
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115 /*
116 * If (flags & REF_HAVE_OLD), check that the reference
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117 * previously had this value (or didn't previously exist, if
118 * `old_oid` is `null_oid`).
4cb77009 119 */
98491298 120 struct object_id old_oid;
6e30b2f6 121
4cb77009 122 /*
91774afc 123 * One or more of REF_NO_DEREF, REF_FORCE_CREATE_REFLOG,
5ac95fee 124 * REF_HAVE_NEW, REF_HAVE_OLD, or backend-specific flags.
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125 */
126 unsigned int flags;
6e30b2f6 127
7d618264 128 void *backend_data;
92b1551b 129 unsigned int type;
4cb77009 130 char *msg;
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131
132 /*
133 * If this ref_update was split off of a symref update via
134 * split_symref_update(), then this member points at that
135 * update. This is used for two purposes:
136 * 1. When reporting errors, we report the refname under which
137 * the update was originally requested.
138 * 2. When we read the old value of this reference, we
139 * propagate it back to its parent update for recording in
140 * the latter's reflog.
141 */
142 struct ref_update *parent_update;
143
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144 const char refname[FLEX_ARRAY];
145};
146
470be518 147int refs_read_raw_ref(struct ref_store *ref_store,
99afe91a 148 const char *refname, struct object_id *oid,
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149 struct strbuf *referent, unsigned int *type);
150
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151/*
152 * Write an error to `err` and return a nonzero value iff the same
153 * refname appears multiple times in `refnames`. `refnames` must be
154 * sorted on entry to this function.
155 */
156int ref_update_reject_duplicates(struct string_list *refnames,
157 struct strbuf *err);
158
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159/*
160 * Add a ref_update with the specified properties to transaction, and
161 * return a pointer to the new object. This function does not verify
78fb4579 162 * that refname is well-formed. new_oid and old_oid are only
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163 * dereferenced if the REF_HAVE_NEW and REF_HAVE_OLD bits,
164 * respectively, are set in flags.
165 */
166struct ref_update *ref_transaction_add_update(
167 struct ref_transaction *transaction,
168 const char *refname, unsigned int flags,
89f3bbdd 169 const struct object_id *new_oid,
170 const struct object_id *old_oid,
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171 const char *msg);
172
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173/*
174 * Transaction states.
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175 *
176 * OPEN: The transaction is initialized and new updates can still be
177 * added to it. An OPEN transaction can be prepared,
178 * committed, freed, or aborted (freeing and aborting an open
179 * transaction are equivalent).
180 *
181 * PREPARED: ref_transaction_prepare(), which locks all of the
182 * references involved in the update and checks that the
183 * update has no errors, has been called successfully for the
184 * transaction. A PREPARED transaction can be committed or
185 * aborted.
186 *
187 * CLOSED: The transaction is no longer active. A transaction becomes
188 * CLOSED if there is a failure while building the transaction
189 * or if a transaction is committed or aborted. A CLOSED
190 * transaction can only be freed.
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191 */
192enum ref_transaction_state {
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193 REF_TRANSACTION_OPEN = 0,
194 REF_TRANSACTION_PREPARED = 1,
195 REF_TRANSACTION_CLOSED = 2
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196};
197
198/*
199 * Data structure for holding a reference transaction, which can
200 * consist of checks and updates to multiple references, carried out
201 * as atomically as possible. This structure is opaque to callers.
202 */
203struct ref_transaction {
c0fe4e8b 204 struct ref_store *ref_store;
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205 struct ref_update **updates;
206 size_t alloc;
207 size_t nr;
208 enum ref_transaction_state state;
3bf4f561 209 void *backend_data;
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210};
211
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212/*
213 * Check for entries in extras that are within the specified
214 * directory, where dirname is a reference directory name including
215 * the trailing slash (e.g., "refs/heads/foo/"). Ignore any
216 * conflicting references that are found in skip. If there is a
217 * conflicting reference, return its name.
218 *
219 * extras and skip must be sorted lists of reference names. Either one
220 * can be NULL, signifying the empty list.
221 */
222const char *find_descendant_ref(const char *dirname,
223 const struct string_list *extras,
224 const struct string_list *skip);
225
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226/*
227 * Check whether an attempt to rename old_refname to new_refname would
228 * cause a D/F conflict with any existing reference (other than
229 * possibly old_refname). If there would be a conflict, emit an error
230 * message and return false; otherwise, return true.
231 *
232 * Note that this function is not safe against all races with other
233 * processes (though rename_ref() catches some races that might get by
234 * this check).
235 */
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236int refs_rename_ref_available(struct ref_store *refs,
237 const char *old_refname,
238 const char *new_refname);
0845122c 239
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240/* We allow "recursive" symbolic refs. Only within reason, though */
241#define SYMREF_MAXDEPTH 5
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242
243/* Include broken references in a do_for_each_ref*() iteration: */
244#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
245
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246/*
247 * Reference iterators
248 *
249 * A reference iterator encapsulates the state of an in-progress
250 * iteration over references. Create an instance of `struct
251 * ref_iterator` via one of the functions in this module.
252 *
253 * A freshly-created ref_iterator doesn't yet point at a reference. To
254 * advance the iterator, call ref_iterator_advance(). If successful,
255 * this sets the iterator's refname, oid, and flags fields to describe
256 * the next reference and returns ITER_OK. The data pointed at by
257 * refname and oid belong to the iterator; if you want to retain them
258 * after calling ref_iterator_advance() again or calling
259 * ref_iterator_abort(), you must make a copy. When the iteration has
260 * been exhausted, ref_iterator_advance() releases any resources
261 * assocated with the iteration, frees the ref_iterator object, and
262 * returns ITER_DONE. If you want to abort the iteration early, call
263 * ref_iterator_abort(), which also frees the ref_iterator object and
264 * any associated resources. If there was an internal error advancing
265 * to the next entry, ref_iterator_advance() aborts the iteration,
266 * frees the ref_iterator, and returns ITER_ERROR.
267 *
268 * The reference currently being looked at can be peeled by calling
269 * ref_iterator_peel(). This function is often faster than peel_ref(),
270 * so it should be preferred when iterating over references.
271 *
272 * Putting it all together, a typical iteration looks like this:
273 *
274 * int ok;
275 * struct ref_iterator *iter = ...;
276 *
277 * while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
278 * if (want_to_stop_iteration()) {
279 * ok = ref_iterator_abort(iter);
280 * break;
281 * }
282 *
283 * // Access information about the current reference:
284 * if (!(iter->flags & REF_ISSYMREF))
285 * printf("%s is %s\n", iter->refname, oid_to_hex(&iter->oid));
286 *
287 * // If you need to peel the reference:
288 * ref_iterator_peel(iter, &oid);
289 * }
290 *
291 * if (ok != ITER_DONE)
292 * handle_error();
293 */
294struct ref_iterator {
295 struct ref_iterator_vtable *vtable;
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296
297 /*
298 * Does this `ref_iterator` iterate over references in order
299 * by refname?
300 */
301 unsigned int ordered : 1;
302
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303 const char *refname;
304 const struct object_id *oid;
305 unsigned int flags;
306};
307
308/*
309 * Advance the iterator to the first or next item and return ITER_OK.
310 * If the iteration is exhausted, free the resources associated with
311 * the ref_iterator and return ITER_DONE. On errors, free the iterator
312 * resources and return ITER_ERROR. It is a bug to use ref_iterator or
313 * call this function again after it has returned ITER_DONE or
314 * ITER_ERROR.
315 */
316int ref_iterator_advance(struct ref_iterator *ref_iterator);
317
318/*
319 * If possible, peel the reference currently being viewed by the
320 * iterator. Return 0 on success.
321 */
322int ref_iterator_peel(struct ref_iterator *ref_iterator,
323 struct object_id *peeled);
324
325/*
326 * End the iteration before it has been exhausted, freeing the
327 * reference iterator and any associated resources and returning
328 * ITER_DONE. If the abort itself failed, return ITER_ERROR.
329 */
330int ref_iterator_abort(struct ref_iterator *ref_iterator);
331
332/*
333 * An iterator over nothing (its first ref_iterator_advance() call
334 * returns ITER_DONE).
335 */
336struct ref_iterator *empty_ref_iterator_begin(void);
337
338/*
339 * Return true iff ref_iterator is an empty_ref_iterator.
340 */
341int is_empty_ref_iterator(struct ref_iterator *ref_iterator);
342
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343/*
344 * Return an iterator that goes over each reference in `refs` for
345 * which the refname begins with prefix. If trim is non-zero, then
346 * trim that many characters off the beginning of each refname. flags
347 * can be DO_FOR_EACH_INCLUDE_BROKEN to include broken references in
8738a8a4 348 * the iteration. The output is ordered by refname.
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349 */
350struct ref_iterator *refs_ref_iterator_begin(
351 struct ref_store *refs,
352 const char *prefix, int trim, int flags);
353
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354/*
355 * A callback function used to instruct merge_ref_iterator how to
356 * interleave the entries from iter0 and iter1. The function should
357 * return one of the constants defined in enum iterator_selection. It
358 * must not advance either of the iterators itself.
359 *
360 * The function must be prepared to handle the case that iter0 and/or
361 * iter1 is NULL, which indicates that the corresponding sub-iterator
362 * has been exhausted. Its return value must be consistent with the
363 * current states of the iterators; e.g., it must not return
364 * ITER_SKIP_1 if iter1 has already been exhausted.
365 */
366typedef enum iterator_selection ref_iterator_select_fn(
367 struct ref_iterator *iter0, struct ref_iterator *iter1,
368 void *cb_data);
369
370/*
371 * Iterate over the entries from iter0 and iter1, with the values
372 * interleaved as directed by the select function. The iterator takes
373 * ownership of iter0 and iter1 and frees them when the iteration is
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374 * over. A derived class should set `ordered` to 1 or 0 based on
375 * whether it generates its output in order by reference name.
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376 */
377struct ref_iterator *merge_ref_iterator_begin(
8738a8a4 378 int ordered,
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379 struct ref_iterator *iter0, struct ref_iterator *iter1,
380 ref_iterator_select_fn *select, void *cb_data);
381
382/*
383 * An iterator consisting of the union of the entries from front and
384 * back. If there are entries common to the two sub-iterators, use the
385 * one from front. Each iterator must iterate over its entries in
386 * strcmp() order by refname for this to work.
387 *
388 * The new iterator takes ownership of its arguments and frees them
389 * when the iteration is over. As a convenience to callers, if front
390 * or back is an empty_ref_iterator, then abort that one immediately
391 * and return the other iterator directly, without wrapping it.
392 */
393struct ref_iterator *overlay_ref_iterator_begin(
394 struct ref_iterator *front, struct ref_iterator *back);
395
396/*
397 * Wrap iter0, only letting through the references whose names start
398 * with prefix. If trim is set, set iter->refname to the name of the
399 * reference with that many characters trimmed off the front;
400 * otherwise set it to the full refname. The new iterator takes over
401 * ownership of iter0 and frees it when iteration is over. It makes
402 * its own copy of prefix.
403 *
404 * As an convenience to callers, if prefix is the empty string and
405 * trim is zero, this function returns iter0 directly, without
406 * wrapping it.
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407 *
408 * The resulting ref_iterator is ordered if iter0 is.
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409 */
410struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
411 const char *prefix,
412 int trim);
413
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414/* Internal implementation of reference iteration: */
415
416/*
417 * Base class constructor for ref_iterators. Initialize the
418 * ref_iterator part of iter, setting its vtable pointer as specified.
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419 * `ordered` should be set to 1 if the iterator will iterate over
420 * references in order by refname; otherwise it should be set to 0.
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421 * This is meant to be called only by the initializers of derived
422 * classes.
423 */
424void base_ref_iterator_init(struct ref_iterator *iter,
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425 struct ref_iterator_vtable *vtable,
426 int ordered);
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427
428/*
429 * Base class destructor for ref_iterators. Destroy the ref_iterator
430 * part of iter and shallow-free the object. This is meant to be
431 * called only by the destructors of derived classes.
432 */
433void base_ref_iterator_free(struct ref_iterator *iter);
434
435/* Virtual function declarations for ref_iterators: */
436
437typedef int ref_iterator_advance_fn(struct ref_iterator *ref_iterator);
438
439typedef int ref_iterator_peel_fn(struct ref_iterator *ref_iterator,
440 struct object_id *peeled);
441
442/*
443 * Implementations of this function should free any resources specific
444 * to the derived class, then call base_ref_iterator_free() to clean
445 * up and free the ref_iterator object.
446 */
447typedef int ref_iterator_abort_fn(struct ref_iterator *ref_iterator);
448
449struct ref_iterator_vtable {
450 ref_iterator_advance_fn *advance;
451 ref_iterator_peel_fn *peel;
452 ref_iterator_abort_fn *abort;
453};
454
93770590 455/*
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MH
456 * current_ref_iter is a performance hack: when iterating over
457 * references using the for_each_ref*() functions, current_ref_iter is
458 * set to the reference iterator before calling the callback function.
459 * If the callback function calls peel_ref(), then peel_ref() first
460 * checks whether the reference to be peeled is the one referred to by
461 * the iterator (it usually is) and if so, asks the iterator for the
462 * peeled version of the reference if it is available. This avoids a
463 * refname lookup in a common case. current_ref_iter is set to NULL
464 * when the iteration is over.
465 */
466extern struct ref_iterator *current_ref_iter;
467
468/*
469 * The common backend for the for_each_*ref* functions. Call fn for
470 * each reference in iter. If the iterator itself ever returns
471 * ITER_ERROR, return -1. If fn ever returns a non-zero value, stop
472 * the iteration and return that value. Otherwise, return 0. In any
473 * case, free the iterator when done. This function is basically an
474 * adapter between the callback style of reference iteration and the
475 * iterator style.
476 */
477int do_for_each_ref_iterator(struct ref_iterator *iter,
478 each_ref_fn fn, void *cb_data);
2d0663b2 479
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DT
480/*
481 * Only include per-worktree refs in a do_for_each_ref*() iteration.
482 * Normally this will be used with a files ref_store, since that's
483 * where all reference backends will presumably store their
484 * per-worktree refs.
485 */
486#define DO_FOR_EACH_PER_WORKTREE_ONLY 0x02
e1e33b72 487
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488struct ref_store;
489
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DT
490/* refs backends */
491
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NTND
492/* ref_store_init flags */
493#define REF_STORE_READ (1 << 0)
494#define REF_STORE_WRITE (1 << 1) /* can perform update operations */
495#define REF_STORE_ODB (1 << 2) /* has access to object database */
496#define REF_STORE_MAIN (1 << 3)
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497#define REF_STORE_ALL_CAPS (REF_STORE_READ | \
498 REF_STORE_WRITE | \
499 REF_STORE_ODB | \
500 REF_STORE_MAIN)
9e7ec634 501
e1e33b72 502/*
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503 * Initialize the ref_store for the specified gitdir. These functions
504 * should call base_ref_store_init() to initialize the shared part of
505 * the ref_store and to record the ref_store for later lookup.
e1e33b72 506 */
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507typedef struct ref_store *ref_store_init_fn(const char *gitdir,
508 unsigned int flags);
e1e33b72 509
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DT
510typedef int ref_init_db_fn(struct ref_store *refs, struct strbuf *err);
511
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512typedef int ref_transaction_prepare_fn(struct ref_store *refs,
513 struct ref_transaction *transaction,
514 struct strbuf *err);
515
516typedef int ref_transaction_finish_fn(struct ref_store *refs,
517 struct ref_transaction *transaction,
518 struct strbuf *err);
519
520typedef int ref_transaction_abort_fn(struct ref_store *refs,
521 struct ref_transaction *transaction,
522 struct strbuf *err);
523
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524typedef int ref_transaction_commit_fn(struct ref_store *refs,
525 struct ref_transaction *transaction,
526 struct strbuf *err);
527
8231527e 528typedef int pack_refs_fn(struct ref_store *ref_store, unsigned int flags);
284689ba
MH
529typedef int create_symref_fn(struct ref_store *ref_store,
530 const char *ref_target,
531 const char *refs_heads_master,
532 const char *logmsg);
64da4199 533typedef int delete_refs_fn(struct ref_store *ref_store, const char *msg,
a27dcf89 534 struct string_list *refnames, unsigned int flags);
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DT
535typedef int rename_ref_fn(struct ref_store *ref_store,
536 const char *oldref, const char *newref,
537 const char *logmsg);
52d59cc6
SD
538typedef int copy_ref_fn(struct ref_store *ref_store,
539 const char *oldref, const char *newref,
540 const char *logmsg);
8231527e 541
1a769003 542/*
e1860571
MH
543 * Iterate over the references in `ref_store` whose names start with
544 * `prefix`. `prefix` is matched as a literal string, without regard
545 * for path separators. If prefix is NULL or the empty string, iterate
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MH
546 * over all references in `ref_store`. The output is ordered by
547 * refname.
1a769003
MH
548 */
549typedef struct ref_iterator *ref_iterator_begin_fn(
550 struct ref_store *ref_store,
551 const char *prefix, unsigned int flags);
552
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DT
553/* reflog functions */
554
555/*
556 * Iterate over the references in the specified ref_store that have a
557 * reflog. The refs are iterated over in arbitrary order.
558 */
559typedef struct ref_iterator *reflog_iterator_begin_fn(
560 struct ref_store *ref_store);
561
562typedef int for_each_reflog_ent_fn(struct ref_store *ref_store,
563 const char *refname,
564 each_reflog_ent_fn fn,
565 void *cb_data);
566typedef int for_each_reflog_ent_reverse_fn(struct ref_store *ref_store,
567 const char *refname,
568 each_reflog_ent_fn fn,
569 void *cb_data);
570typedef int reflog_exists_fn(struct ref_store *ref_store, const char *refname);
571typedef int create_reflog_fn(struct ref_store *ref_store, const char *refname,
572 int force_create, struct strbuf *err);
573typedef int delete_reflog_fn(struct ref_store *ref_store, const char *refname);
574typedef int reflog_expire_fn(struct ref_store *ref_store,
0155f710 575 const char *refname, const struct object_id *oid,
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DT
576 unsigned int flags,
577 reflog_expiry_prepare_fn prepare_fn,
578 reflog_expiry_should_prune_fn should_prune_fn,
579 reflog_expiry_cleanup_fn cleanup_fn,
580 void *policy_cb_data);
581
cf596442 582/*
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MH
583 * Read a reference from the specified reference store, non-recursively.
584 * Set type to describe the reference, and:
cf596442 585 *
99afe91a 586 * - If refname is the name of a normal reference, fill in oid
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MH
587 * (leaving referent unchanged).
588 *
589 * - If refname is the name of a symbolic reference, write the full
590 * name of the reference to which it refers (e.g.
591 * "refs/heads/master") to referent and set the REF_ISSYMREF bit in
99afe91a 592 * type (leaving oid unchanged). The caller is responsible for
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593 * validating that referent is a valid reference name.
594 *
595 * WARNING: refname might be used as part of a filename, so it is
596 * important from a security standpoint that it be safe in the sense
597 * of refname_is_safe(). Moreover, for symrefs this function sets
598 * referent to whatever the repository says, which might not be a
599 * properly-formatted or even safe reference name. NEITHER INPUT NOR
600 * OUTPUT REFERENCE NAMES ARE VALIDATED WITHIN THIS FUNCTION.
601 *
602 * Return 0 on success. If the ref doesn't exist, set errno to ENOENT
603 * and return -1. If the ref exists but is neither a symbolic ref nor
99afe91a 604 * an object ID, it is broken; set REF_ISBROKEN in type, set errno to
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605 * EINVAL, and return -1. If there is another error reading the ref,
606 * set errno appropriately and return -1.
607 *
608 * Backend-specific flags might be set in type as well, regardless of
609 * outcome.
610 *
611 * It is OK for refname to point into referent. If so:
612 *
613 * - if the function succeeds with REF_ISSYMREF, referent will be
614 * overwritten and the memory formerly pointed to by it might be
615 * changed or even freed.
616 *
617 * - in all other cases, referent will be untouched, and therefore
618 * refname will still be valid and unchanged.
619 */
e1e33b72 620typedef int read_raw_ref_fn(struct ref_store *ref_store,
99afe91a 621 const char *refname, struct object_id *oid,
e1e33b72 622 struct strbuf *referent, unsigned int *type);
127b42a1 623
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624struct ref_storage_be {
625 struct ref_storage_be *next;
626 const char *name;
00eebe35 627 ref_store_init_fn *init;
6fb5acfd 628 ref_init_db_fn *init_db;
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629
630 ref_transaction_prepare_fn *transaction_prepare;
631 ref_transaction_finish_fn *transaction_finish;
632 ref_transaction_abort_fn *transaction_abort;
fc681463 633 ref_transaction_commit_fn *initial_transaction_commit;
e1e33b72 634
8231527e 635 pack_refs_fn *pack_refs;
284689ba 636 create_symref_fn *create_symref;
a27dcf89 637 delete_refs_fn *delete_refs;
9b6b40d9 638 rename_ref_fn *rename_ref;
52d59cc6 639 copy_ref_fn *copy_ref;
8231527e 640
1a769003 641 ref_iterator_begin_fn *iterator_begin;
e1e33b72 642 read_raw_ref_fn *read_raw_ref;
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643
644 reflog_iterator_begin_fn *reflog_iterator_begin;
645 for_each_reflog_ent_fn *for_each_reflog_ent;
646 for_each_reflog_ent_reverse_fn *for_each_reflog_ent_reverse;
647 reflog_exists_fn *reflog_exists;
648 create_reflog_fn *create_reflog;
649 delete_reflog_fn *delete_reflog;
650 reflog_expire_fn *reflog_expire;
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651};
652
653extern struct ref_storage_be refs_be_files;
e0cc8ac8 654extern struct ref_storage_be refs_be_packed;
3dce444f 655
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656/*
657 * A representation of the reference store for the main repository or
658 * a submodule. The ref_store instances for submodules are kept in a
659 * linked list.
660 */
661struct ref_store {
662 /* The backend describing this ref_store's storage scheme: */
663 const struct ref_storage_be *be;
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664};
665
666/*
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667 * Fill in the generic part of refs and add it to our collection of
668 * reference stores.
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669 */
670void base_ref_store_init(struct ref_store *refs,
fbfd0a29 671 const struct ref_storage_be *be);
00eebe35 672
4cb77009 673#endif /* REFS_REFS_INTERNAL_H */