Merge branch 'ds/commit-graph-with-grafts' into maint
[git/git.git] / refs.h
1 #ifndef REFS_H
2 #define REFS_H
3
4 struct object_id;
5 struct ref_store;
6 struct repository;
7 struct strbuf;
8 struct string_list;
9 struct string_list_item;
10 struct worktree;
11
12 /*
13 * Resolve a reference, recursively following symbolic refererences.
14 *
15 * Return the name of the non-symbolic reference that ultimately pointed
16 * at the resolved object name. The return value, if not NULL, is a
17 * pointer into either a static buffer or the input ref.
18 *
19 * If oid is non-NULL, store the referred-to object's name in it.
20 *
21 * If the reference cannot be resolved to an object, the behavior
22 * depends on the RESOLVE_REF_READING flag:
23 *
24 * - If RESOLVE_REF_READING is set, return NULL.
25 *
26 * - If RESOLVE_REF_READING is not set, clear oid and return the name of
27 * the last reference name in the chain, which will either be a non-symbolic
28 * reference or an undefined reference. If this is a prelude to
29 * "writing" to the ref, the return value is the name of the ref
30 * that will actually be created or changed.
31 *
32 * If the RESOLVE_REF_NO_RECURSE flag is passed, only resolves one
33 * level of symbolic reference. The value stored in oid for a symbolic
34 * reference will always be null_oid in this case, and the return
35 * value is the reference that the symref refers to directly.
36 *
37 * If flags is non-NULL, set the value that it points to the
38 * combination of REF_ISPACKED (if the reference was found among the
39 * packed references), REF_ISSYMREF (if the initial reference was a
40 * symbolic reference), REF_BAD_NAME (if the reference name is ill
41 * formed --- see RESOLVE_REF_ALLOW_BAD_NAME below), and REF_ISBROKEN
42 * (if the ref is malformed or has a bad name). See refs.h for more detail
43 * on each flag.
44 *
45 * If ref is not a properly-formatted, normalized reference, return
46 * NULL. If more than MAXDEPTH recursive symbolic lookups are needed,
47 * give up and return NULL.
48 *
49 * RESOLVE_REF_ALLOW_BAD_NAME allows resolving refs even when their
50 * name is invalid according to git-check-ref-format(1). If the name
51 * is bad then the value stored in oid will be null_oid and the two
52 * flags REF_ISBROKEN and REF_BAD_NAME will be set.
53 *
54 * Even with RESOLVE_REF_ALLOW_BAD_NAME, names that escape the refs/
55 * directory and do not consist of all caps and underscores cannot be
56 * resolved. The function returns NULL for such ref names.
57 * Caps and underscores refers to the special refs, such as HEAD,
58 * FETCH_HEAD and friends, that all live outside of the refs/ directory.
59 */
60 #define RESOLVE_REF_READING 0x01
61 #define RESOLVE_REF_NO_RECURSE 0x02
62 #define RESOLVE_REF_ALLOW_BAD_NAME 0x04
63
64 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
65 const char *refname,
66 int resolve_flags,
67 struct object_id *oid,
68 int *flags);
69 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
70 struct object_id *oid, int *flags);
71
72 char *refs_resolve_refdup(struct ref_store *refs,
73 const char *refname, int resolve_flags,
74 struct object_id *oid, int *flags);
75 char *resolve_refdup(const char *refname, int resolve_flags,
76 struct object_id *oid, int *flags);
77
78 int refs_read_ref_full(struct ref_store *refs, const char *refname,
79 int resolve_flags, struct object_id *oid, int *flags);
80 int read_ref_full(const char *refname, int resolve_flags,
81 struct object_id *oid, int *flags);
82 int read_ref(const char *refname, struct object_id *oid);
83
84 /*
85 * Return 0 if a reference named refname could be created without
86 * conflicting with the name of an existing reference. Otherwise,
87 * return a negative value and write an explanation to err. If extras
88 * is non-NULL, it is a list of additional refnames with which refname
89 * is not allowed to conflict. If skip is non-NULL, ignore potential
90 * conflicts with refs in skip (e.g., because they are scheduled for
91 * deletion in the same operation). Behavior is undefined if the same
92 * name is listed in both extras and skip.
93 *
94 * Two reference names conflict if one of them exactly matches the
95 * leading components of the other; e.g., "foo/bar" conflicts with
96 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
97 * "foo/barbados".
98 *
99 * extras and skip must be sorted.
100 */
101
102 int refs_verify_refname_available(struct ref_store *refs,
103 const char *refname,
104 const struct string_list *extras,
105 const struct string_list *skip,
106 struct strbuf *err);
107
108 int ref_exists(const char *refname);
109
110 int should_autocreate_reflog(const char *refname);
111
112 int is_branch(const char *refname);
113
114 extern int refs_init_db(struct strbuf *err);
115
116 /*
117 * If refname is a non-symbolic reference that refers to a tag object,
118 * and the tag can be (recursively) dereferenced to a non-tag object,
119 * store the object ID of the referred-to object to oid and return 0.
120 * If any of these conditions are not met, return a non-zero value.
121 * Symbolic references are considered unpeelable, even if they
122 * ultimately resolve to a peelable tag.
123 */
124 int refs_peel_ref(struct ref_store *refs, const char *refname,
125 struct object_id *oid);
126 int peel_ref(const char *refname, struct object_id *oid);
127
128 /**
129 * Resolve refname in the nested "gitlink" repository in the specified
130 * submodule (which must be non-NULL). If the resolution is
131 * successful, return 0 and set oid to the name of the object;
132 * otherwise, return a non-zero value.
133 */
134 int resolve_gitlink_ref(const char *submodule, const char *refname,
135 struct object_id *oid);
136
137 /*
138 * Return true iff abbrev_name is a possible abbreviation for
139 * full_name according to the rules defined by ref_rev_parse_rules in
140 * refs.c.
141 */
142 int refname_match(const char *abbrev_name, const char *full_name);
143
144 /*
145 * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add
146 * the results to 'prefixes'
147 */
148 struct argv_array;
149 void expand_ref_prefix(struct argv_array *prefixes, const char *prefix);
150
151 int expand_ref(const char *str, int len, struct object_id *oid, char **ref);
152 int dwim_ref(const char *str, int len, struct object_id *oid, char **ref);
153 int dwim_log(const char *str, int len, struct object_id *oid, char **ref);
154
155 /*
156 * A ref_transaction represents a collection of reference updates that
157 * should succeed or fail together.
158 *
159 * Calling sequence
160 * ----------------
161 *
162 * - Allocate and initialize a `struct ref_transaction` by calling
163 * `ref_transaction_begin()`.
164 *
165 * - Specify the intended ref updates by calling one or more of the
166 * following functions:
167 * - `ref_transaction_update()`
168 * - `ref_transaction_create()`
169 * - `ref_transaction_delete()`
170 * - `ref_transaction_verify()`
171 *
172 * - Then either:
173 *
174 * - Optionally call `ref_transaction_prepare()` to prepare the
175 * transaction. This locks all references, checks preconditions,
176 * etc. but doesn't finalize anything. If this step fails, the
177 * transaction has been closed and can only be freed. If this step
178 * succeeds, then `ref_transaction_commit()` is almost certain to
179 * succeed. However, you can still call `ref_transaction_abort()`
180 * if you decide not to commit the transaction after all.
181 *
182 * - Call `ref_transaction_commit()` to execute the transaction,
183 * make the changes permanent, and release all locks. If you
184 * haven't already called `ref_transaction_prepare()`, then
185 * `ref_transaction_commit()` calls it for you.
186 *
187 * Or
188 *
189 * - Call `initial_ref_transaction_commit()` if the ref database is
190 * known to be empty and have no other writers (e.g. during
191 * clone). This is likely to be much faster than
192 * `ref_transaction_commit()`. `ref_transaction_prepare()` should
193 * *not* be called before `initial_ref_transaction_commit()`.
194 *
195 * - Then finally, call `ref_transaction_free()` to free the
196 * `ref_transaction` data structure.
197 *
198 * At any time before calling `ref_transaction_commit()`, you can call
199 * `ref_transaction_abort()` to abort the transaction, rollback any
200 * locks, and free any associated resources (including the
201 * `ref_transaction` data structure).
202 *
203 * Putting it all together, a complete reference update looks like
204 *
205 * struct ref_transaction *transaction;
206 * struct strbuf err = STRBUF_INIT;
207 * int ret = 0;
208 *
209 * transaction = ref_store_transaction_begin(refs, &err);
210 * if (!transaction ||
211 * ref_transaction_update(...) ||
212 * ref_transaction_create(...) ||
213 * ...etc... ||
214 * ref_transaction_commit(transaction, &err)) {
215 * error("%s", err.buf);
216 * ret = -1;
217 * }
218 * ref_transaction_free(transaction);
219 * strbuf_release(&err);
220 * return ret;
221 *
222 * Error handling
223 * --------------
224 *
225 * On error, transaction functions append a message about what
226 * went wrong to the 'err' argument. The message mentions what
227 * ref was being updated (if any) when the error occurred so it
228 * can be passed to 'die' or 'error' as-is.
229 *
230 * The message is appended to err without first clearing err.
231 * err will not be '\n' terminated.
232 *
233 * Caveats
234 * -------
235 *
236 * Note that no locks are taken, and no refs are read, until
237 * `ref_transaction_prepare()` or `ref_transaction_commit()` is
238 * called. So, for example, `ref_transaction_verify()` won't report a
239 * verification failure until the commit is attempted.
240 */
241 struct ref_transaction;
242
243 /*
244 * Bit values set in the flags argument passed to each_ref_fn() and
245 * stored in ref_iterator::flags. Other bits are for internal use
246 * only:
247 */
248
249 /* Reference is a symbolic reference. */
250 #define REF_ISSYMREF 0x01
251
252 /* Reference is a packed reference. */
253 #define REF_ISPACKED 0x02
254
255 /*
256 * Reference cannot be resolved to an object name: dangling symbolic
257 * reference (directly or indirectly), corrupt reference file,
258 * reference exists but name is bad, or symbolic reference refers to
259 * ill-formatted reference name.
260 */
261 #define REF_ISBROKEN 0x04
262
263 /*
264 * Reference name is not well formed.
265 *
266 * See git-check-ref-format(1) for the definition of well formed ref names.
267 */
268 #define REF_BAD_NAME 0x08
269
270 /*
271 * The signature for the callback function for the for_each_*()
272 * functions below. The memory pointed to by the refname and oid
273 * arguments is only guaranteed to be valid for the duration of a
274 * single callback invocation.
275 */
276 typedef int each_ref_fn(const char *refname,
277 const struct object_id *oid, int flags, void *cb_data);
278
279 /*
280 * The same as each_ref_fn, but also with a repository argument that
281 * contains the repository associated with the callback.
282 */
283 typedef int each_repo_ref_fn(struct repository *r,
284 const char *refname,
285 const struct object_id *oid,
286 int flags,
287 void *cb_data);
288
289 /*
290 * The following functions invoke the specified callback function for
291 * each reference indicated. If the function ever returns a nonzero
292 * value, stop the iteration and return that value. Please note that
293 * it is not safe to modify references while an iteration is in
294 * progress, unless the same callback function invocation that
295 * modifies the reference also returns a nonzero value to immediately
296 * stop the iteration. Returned references are sorted.
297 */
298 int refs_head_ref(struct ref_store *refs,
299 each_ref_fn fn, void *cb_data);
300 int refs_for_each_ref(struct ref_store *refs,
301 each_ref_fn fn, void *cb_data);
302 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
303 each_ref_fn fn, void *cb_data);
304 int refs_for_each_tag_ref(struct ref_store *refs,
305 each_ref_fn fn, void *cb_data);
306 int refs_for_each_branch_ref(struct ref_store *refs,
307 each_ref_fn fn, void *cb_data);
308 int refs_for_each_remote_ref(struct ref_store *refs,
309 each_ref_fn fn, void *cb_data);
310
311 int head_ref(each_ref_fn fn, void *cb_data);
312 int for_each_ref(each_ref_fn fn, void *cb_data);
313 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data);
314 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
315 each_ref_fn fn, void *cb_data,
316 unsigned int broken);
317 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data,
318 unsigned int broken);
319 int for_each_tag_ref(each_ref_fn fn, void *cb_data);
320 int for_each_branch_ref(each_ref_fn fn, void *cb_data);
321 int for_each_remote_ref(each_ref_fn fn, void *cb_data);
322 int for_each_replace_ref(struct repository *r, each_repo_ref_fn fn, void *cb_data);
323 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data);
324 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
325 const char *prefix, void *cb_data);
326
327 int head_ref_namespaced(each_ref_fn fn, void *cb_data);
328 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data);
329
330 /* can be used to learn about broken ref and symref */
331 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data);
332 int for_each_rawref(each_ref_fn fn, void *cb_data);
333
334 /*
335 * Normalizes partial refs to their fully qualified form.
336 * Will prepend <prefix> to the <pattern> if it doesn't start with 'refs/'.
337 * <prefix> will default to 'refs/' if NULL.
338 *
339 * item.string will be set to the result.
340 * item.util will be set to NULL if <pattern> contains glob characters, or
341 * non-NULL if it doesn't.
342 */
343 void normalize_glob_ref(struct string_list_item *item, const char *prefix,
344 const char *pattern);
345
346 /*
347 * Returns 0 if refname matches any of the exclude_patterns, or if it doesn't
348 * match any of the include_patterns. Returns 1 otherwise.
349 *
350 * If pattern list is NULL or empty, matching against that list is skipped.
351 * This has the effect of matching everything by default, unless the user
352 * specifies rules otherwise.
353 */
354 int ref_filter_match(const char *refname,
355 const struct string_list *include_patterns,
356 const struct string_list *exclude_patterns);
357
358 static inline const char *has_glob_specials(const char *pattern)
359 {
360 return strpbrk(pattern, "?*[");
361 }
362
363 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname);
364 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt,
365 const struct string_list *refnames);
366
367 /*
368 * Flags for controlling behaviour of pack_refs()
369 * PACK_REFS_PRUNE: Prune loose refs after packing
370 * PACK_REFS_ALL: Pack _all_ refs, not just tags and already packed refs
371 */
372 #define PACK_REFS_PRUNE 0x0001
373 #define PACK_REFS_ALL 0x0002
374
375 /*
376 * Write a packed-refs file for the current repository.
377 * flags: Combination of the above PACK_REFS_* flags.
378 */
379 int refs_pack_refs(struct ref_store *refs, unsigned int flags);
380
381 /*
382 * Setup reflog before using. Fill in err and return -1 on failure.
383 */
384 int refs_create_reflog(struct ref_store *refs, const char *refname,
385 int force_create, struct strbuf *err);
386 int safe_create_reflog(const char *refname, int force_create, struct strbuf *err);
387
388 /** Reads log for the value of ref during at_time. **/
389 int read_ref_at(const char *refname, unsigned int flags,
390 timestamp_t at_time, int cnt,
391 struct object_id *oid, char **msg,
392 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt);
393
394 /** Check if a particular reflog exists */
395 int refs_reflog_exists(struct ref_store *refs, const char *refname);
396 int reflog_exists(const char *refname);
397
398 /*
399 * Delete the specified reference. If old_oid is non-NULL, then
400 * verify that the current value of the reference is old_oid before
401 * deleting it. If old_oid is NULL, delete the reference if it
402 * exists, regardless of its old value. It is an error for old_oid to
403 * be null_oid. msg and flags are passed through to
404 * ref_transaction_delete().
405 */
406 int refs_delete_ref(struct ref_store *refs, const char *msg,
407 const char *refname,
408 const struct object_id *old_oid,
409 unsigned int flags);
410 int delete_ref(const char *msg, const char *refname,
411 const struct object_id *old_oid, unsigned int flags);
412
413 /*
414 * Delete the specified references. If there are any problems, emit
415 * errors but attempt to keep going (i.e., the deletes are not done in
416 * an all-or-nothing transaction). msg and flags are passed through to
417 * ref_transaction_delete().
418 */
419 int refs_delete_refs(struct ref_store *refs, const char *msg,
420 struct string_list *refnames, unsigned int flags);
421 int delete_refs(const char *msg, struct string_list *refnames,
422 unsigned int flags);
423
424 /** Delete a reflog */
425 int refs_delete_reflog(struct ref_store *refs, const char *refname);
426 int delete_reflog(const char *refname);
427
428 /* iterate over reflog entries */
429 typedef int each_reflog_ent_fn(
430 struct object_id *old_oid, struct object_id *new_oid,
431 const char *committer, timestamp_t timestamp,
432 int tz, const char *msg, void *cb_data);
433
434 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
435 each_reflog_ent_fn fn, void *cb_data);
436 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
437 const char *refname,
438 each_reflog_ent_fn fn,
439 void *cb_data);
440 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data);
441 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data);
442
443 /*
444 * Calls the specified function for each reflog file until it returns nonzero,
445 * and returns the value. Reflog file order is unspecified.
446 */
447 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data);
448 int for_each_reflog(each_ref_fn fn, void *cb_data);
449
450 #define REFNAME_ALLOW_ONELEVEL 1
451 #define REFNAME_REFSPEC_PATTERN 2
452
453 /*
454 * Return 0 iff refname has the correct format for a refname according
455 * to the rules described in Documentation/git-check-ref-format.txt.
456 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level
457 * reference names. If REFNAME_REFSPEC_PATTERN is set in flags, then
458 * allow a single "*" wildcard character in the refspec. No leading or
459 * repeated slashes are accepted.
460 */
461 int check_refname_format(const char *refname, int flags);
462
463 const char *prettify_refname(const char *refname);
464
465 char *shorten_unambiguous_ref(const char *refname, int strict);
466
467 /** rename ref, return 0 on success **/
468 int refs_rename_ref(struct ref_store *refs, const char *oldref,
469 const char *newref, const char *logmsg);
470 int rename_ref(const char *oldref, const char *newref,
471 const char *logmsg);
472
473 /** copy ref, return 0 on success **/
474 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
475 const char *newref, const char *logmsg);
476 int copy_existing_ref(const char *oldref, const char *newref,
477 const char *logmsg);
478
479 int refs_create_symref(struct ref_store *refs, const char *refname,
480 const char *target, const char *logmsg);
481 int create_symref(const char *refname, const char *target, const char *logmsg);
482
483 enum action_on_err {
484 UPDATE_REFS_MSG_ON_ERR,
485 UPDATE_REFS_DIE_ON_ERR,
486 UPDATE_REFS_QUIET_ON_ERR
487 };
488
489 /*
490 * Begin a reference transaction. The reference transaction must
491 * be freed by calling ref_transaction_free().
492 */
493 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
494 struct strbuf *err);
495 struct ref_transaction *ref_transaction_begin(struct strbuf *err);
496
497 /*
498 * Reference transaction updates
499 *
500 * The following four functions add a reference check or update to a
501 * ref_transaction. They have some common similar parameters:
502 *
503 * transaction -- a pointer to an open ref_transaction, obtained
504 * from ref_transaction_begin().
505 *
506 * refname -- the name of the reference to be affected.
507 *
508 * new_oid -- the object ID that should be set to be the new value
509 * of the reference. Some functions allow this parameter to be
510 * NULL, meaning that the reference is not changed, or
511 * null_oid, meaning that the reference should be deleted. A
512 * copy of this value is made in the transaction.
513 *
514 * old_oid -- the object ID that the reference must have before
515 * the update. Some functions allow this parameter to be NULL,
516 * meaning that the old value of the reference is not checked,
517 * or null_oid, meaning that the reference must not exist
518 * before the update. A copy of this value is made in the
519 * transaction.
520 *
521 * flags -- flags affecting the update, passed to
522 * update_ref_lock(). Possible flags: REF_NO_DEREF,
523 * REF_FORCE_CREATE_REFLOG. See those constants for more
524 * information.
525 *
526 * msg -- a message describing the change (for the reflog).
527 *
528 * err -- a strbuf for receiving a description of any error that
529 * might have occurred.
530 *
531 * The functions make internal copies of refname and msg, so the
532 * caller retains ownership of these parameters.
533 *
534 * The functions return 0 on success and non-zero on failure. A
535 * failure means that the transaction as a whole has failed and needs
536 * to be rolled back.
537 */
538
539 /*
540 * The following flags can be passed to ref_transaction_update() etc.
541 * Internally, they are stored in `ref_update::flags`, along with some
542 * internal flags.
543 */
544
545 /*
546 * Act on the ref directly; i.e., without dereferencing symbolic refs.
547 * If this flag is not specified, then symbolic references are
548 * dereferenced and the update is applied to the referent.
549 */
550 #define REF_NO_DEREF (1 << 0)
551
552 /*
553 * Force the creation of a reflog for this reference, even if it
554 * didn't previously have a reflog.
555 */
556 #define REF_FORCE_CREATE_REFLOG (1 << 1)
557
558 /*
559 * Bitmask of all of the flags that are allowed to be passed in to
560 * ref_transaction_update() and friends:
561 */
562 #define REF_TRANSACTION_UPDATE_ALLOWED_FLAGS \
563 (REF_NO_DEREF | REF_FORCE_CREATE_REFLOG)
564
565 /*
566 * Add a reference update to transaction. `new_oid` is the value that
567 * the reference should have after the update, or `null_oid` if it
568 * should be deleted. If `new_oid` is NULL, then the reference is not
569 * changed at all. `old_oid` is the value that the reference must have
570 * before the update, or `null_oid` if it must not have existed
571 * beforehand. The old value is checked after the lock is taken to
572 * prevent races. If the old value doesn't agree with old_oid, the
573 * whole transaction fails. If old_oid is NULL, then the previous
574 * value is not checked.
575 *
576 * See the above comment "Reference transaction updates" for more
577 * information.
578 */
579 int ref_transaction_update(struct ref_transaction *transaction,
580 const char *refname,
581 const struct object_id *new_oid,
582 const struct object_id *old_oid,
583 unsigned int flags, const char *msg,
584 struct strbuf *err);
585
586 /*
587 * Add a reference creation to transaction. new_oid is the value that
588 * the reference should have after the update; it must not be
589 * null_oid. It is verified that the reference does not exist
590 * already.
591 *
592 * See the above comment "Reference transaction updates" for more
593 * information.
594 */
595 int ref_transaction_create(struct ref_transaction *transaction,
596 const char *refname,
597 const struct object_id *new_oid,
598 unsigned int flags, const char *msg,
599 struct strbuf *err);
600
601 /*
602 * Add a reference deletion to transaction. If old_oid is non-NULL,
603 * then it holds the value that the reference should have had before
604 * the update (which must not be null_oid).
605 *
606 * See the above comment "Reference transaction updates" for more
607 * information.
608 */
609 int ref_transaction_delete(struct ref_transaction *transaction,
610 const char *refname,
611 const struct object_id *old_oid,
612 unsigned int flags, const char *msg,
613 struct strbuf *err);
614
615 /*
616 * Verify, within a transaction, that refname has the value old_oid,
617 * or, if old_oid is null_oid, then verify that the reference
618 * doesn't exist. old_oid must be non-NULL.
619 *
620 * See the above comment "Reference transaction updates" for more
621 * information.
622 */
623 int ref_transaction_verify(struct ref_transaction *transaction,
624 const char *refname,
625 const struct object_id *old_oid,
626 unsigned int flags,
627 struct strbuf *err);
628
629 /* Naming conflict (for example, the ref names A and A/B conflict). */
630 #define TRANSACTION_NAME_CONFLICT -1
631 /* All other errors. */
632 #define TRANSACTION_GENERIC_ERROR -2
633
634 /*
635 * Perform the preparatory stages of committing `transaction`. Acquire
636 * any needed locks, check preconditions, etc.; basically, do as much
637 * as possible to ensure that the transaction will be able to go
638 * through, stopping just short of making any irrevocable or
639 * user-visible changes. The updates that this function prepares can
640 * be finished up by calling `ref_transaction_commit()` or rolled back
641 * by calling `ref_transaction_abort()`.
642 *
643 * On success, return 0 and leave the transaction in "prepared" state.
644 * On failure, abort the transaction, write an error message to `err`,
645 * and return one of the `TRANSACTION_*` constants.
646 *
647 * Callers who don't need such fine-grained control over committing
648 * reference transactions should just call `ref_transaction_commit()`.
649 */
650 int ref_transaction_prepare(struct ref_transaction *transaction,
651 struct strbuf *err);
652
653 /*
654 * Commit all of the changes that have been queued in transaction, as
655 * atomically as possible. On success, return 0 and leave the
656 * transaction in "closed" state. On failure, roll back the
657 * transaction, write an error message to `err`, and return one of the
658 * `TRANSACTION_*` constants
659 */
660 int ref_transaction_commit(struct ref_transaction *transaction,
661 struct strbuf *err);
662
663 /*
664 * Abort `transaction`, which has been begun and possibly prepared,
665 * but not yet committed.
666 */
667 int ref_transaction_abort(struct ref_transaction *transaction,
668 struct strbuf *err);
669
670 /*
671 * Like ref_transaction_commit(), but optimized for creating
672 * references when originally initializing a repository (e.g., by "git
673 * clone"). It writes the new references directly to packed-refs
674 * without locking the individual references.
675 *
676 * It is a bug to call this function when there might be other
677 * processes accessing the repository or if there are existing
678 * references that might conflict with the ones being created. All
679 * old_oid values must either be absent or null_oid.
680 */
681 int initial_ref_transaction_commit(struct ref_transaction *transaction,
682 struct strbuf *err);
683
684 /*
685 * Free `*transaction` and all associated data.
686 */
687 void ref_transaction_free(struct ref_transaction *transaction);
688
689 /**
690 * Lock, update, and unlock a single reference. This function
691 * basically does a transaction containing a single call to
692 * ref_transaction_update(). The parameters to this function have the
693 * same meaning as the corresponding parameters to
694 * ref_transaction_update(). Handle errors as requested by the `onerr`
695 * argument.
696 */
697 int refs_update_ref(struct ref_store *refs, const char *msg, const char *refname,
698 const struct object_id *new_oid, const struct object_id *old_oid,
699 unsigned int flags, enum action_on_err onerr);
700 int update_ref(const char *msg, const char *refname,
701 const struct object_id *new_oid, const struct object_id *old_oid,
702 unsigned int flags, enum action_on_err onerr);
703
704 int parse_hide_refs_config(const char *var, const char *value, const char *);
705
706 /*
707 * Check whether a ref is hidden. If no namespace is set, both the first and
708 * the second parameter point to the full ref name. If a namespace is set and
709 * the ref is inside that namespace, the first parameter is a pointer to the
710 * name of the ref with the namespace prefix removed. If a namespace is set and
711 * the ref is outside that namespace, the first parameter is NULL. The second
712 * parameter always points to the full ref name.
713 */
714 int ref_is_hidden(const char *, const char *);
715
716 enum ref_type {
717 REF_TYPE_PER_WORKTREE,
718 REF_TYPE_PSEUDOREF,
719 REF_TYPE_NORMAL,
720 };
721
722 enum ref_type ref_type(const char *refname);
723
724 enum expire_reflog_flags {
725 EXPIRE_REFLOGS_DRY_RUN = 1 << 0,
726 EXPIRE_REFLOGS_UPDATE_REF = 1 << 1,
727 EXPIRE_REFLOGS_VERBOSE = 1 << 2,
728 EXPIRE_REFLOGS_REWRITE = 1 << 3
729 };
730
731 /*
732 * The following interface is used for reflog expiration. The caller
733 * calls reflog_expire(), supplying it with three callback functions,
734 * of the following types. The callback functions define the
735 * expiration policy that is desired.
736 *
737 * reflog_expiry_prepare_fn -- Called once after the reference is
738 * locked.
739 *
740 * reflog_expiry_should_prune_fn -- Called once for each entry in the
741 * existing reflog. It should return true iff that entry should be
742 * pruned.
743 *
744 * reflog_expiry_cleanup_fn -- Called once before the reference is
745 * unlocked again.
746 */
747 typedef void reflog_expiry_prepare_fn(const char *refname,
748 const struct object_id *oid,
749 void *cb_data);
750 typedef int reflog_expiry_should_prune_fn(struct object_id *ooid,
751 struct object_id *noid,
752 const char *email,
753 timestamp_t timestamp, int tz,
754 const char *message, void *cb_data);
755 typedef void reflog_expiry_cleanup_fn(void *cb_data);
756
757 /*
758 * Expire reflog entries for the specified reference. oid is the old
759 * value of the reference. flags is a combination of the constants in
760 * enum expire_reflog_flags. The three function pointers are described
761 * above. On success, return zero.
762 */
763 int refs_reflog_expire(struct ref_store *refs,
764 const char *refname,
765 const struct object_id *oid,
766 unsigned int flags,
767 reflog_expiry_prepare_fn prepare_fn,
768 reflog_expiry_should_prune_fn should_prune_fn,
769 reflog_expiry_cleanup_fn cleanup_fn,
770 void *policy_cb_data);
771 int reflog_expire(const char *refname, const struct object_id *oid,
772 unsigned int flags,
773 reflog_expiry_prepare_fn prepare_fn,
774 reflog_expiry_should_prune_fn should_prune_fn,
775 reflog_expiry_cleanup_fn cleanup_fn,
776 void *policy_cb_data);
777
778 int ref_storage_backend_exists(const char *name);
779
780 struct ref_store *get_main_ref_store(struct repository *r);
781 /*
782 * Return the ref_store instance for the specified submodule. For the
783 * main repository, use submodule==NULL; such a call cannot fail. For
784 * a submodule, the submodule must exist and be a nonbare repository,
785 * otherwise return NULL. If the requested reference store has not yet
786 * been initialized, initialize it first.
787 *
788 * For backwards compatibility, submodule=="" is treated the same as
789 * submodule==NULL.
790 */
791 struct ref_store *get_submodule_ref_store(const char *submodule);
792 struct ref_store *get_worktree_ref_store(const struct worktree *wt);
793
794 #endif /* REFS_H */