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