Merge branch 'vn/line-log-memcpy-size-fix' into maint
[git/raj.git] / refs.h
blob9fbff90e79bfc45fada65651cd01765b17376249
1 #ifndef REFS_H
2 #define REFS_H
4 /*
5 * Resolve a reference, recursively following symbolic refererences.
7 * Store the referred-to object's name in sha1 and return the name of
8 * the non-symbolic reference that ultimately pointed at it. The
9 * return value, if not NULL, is a pointer into either a static buffer
10 * or the input ref.
12 * If the reference cannot be resolved to an object, the behavior
13 * depends on the RESOLVE_REF_READING flag:
15 * - If RESOLVE_REF_READING is set, return NULL.
17 * - If RESOLVE_REF_READING is not set, clear sha1 and return the name of
18 * the last reference name in the chain, which will either be a non-symbolic
19 * reference or an undefined reference. If this is a prelude to
20 * "writing" to the ref, the return value is the name of the ref
21 * that will actually be created or changed.
23 * If the RESOLVE_REF_NO_RECURSE flag is passed, only resolves one
24 * level of symbolic reference. The value stored in sha1 for a symbolic
25 * reference will always be null_sha1 in this case, and the return
26 * value is the reference that the symref refers to directly.
28 * If flags is non-NULL, set the value that it points to the
29 * combination of REF_ISPACKED (if the reference was found among the
30 * packed references), REF_ISSYMREF (if the initial reference was a
31 * symbolic reference), REF_BAD_NAME (if the reference name is ill
32 * formed --- see RESOLVE_REF_ALLOW_BAD_NAME below), and REF_ISBROKEN
33 * (if the ref is malformed or has a bad name). See refs.h for more detail
34 * on each flag.
36 * If ref is not a properly-formatted, normalized reference, return
37 * NULL. If more than MAXDEPTH recursive symbolic lookups are needed,
38 * give up and return NULL.
40 * RESOLVE_REF_ALLOW_BAD_NAME allows resolving refs even when their
41 * name is invalid according to git-check-ref-format(1). If the name
42 * is bad then the value stored in sha1 will be null_sha1 and the two
43 * flags REF_ISBROKEN and REF_BAD_NAME will be set.
45 * Even with RESOLVE_REF_ALLOW_BAD_NAME, names that escape the refs/
46 * directory and do not consist of all caps and underscores cannot be
47 * resolved. The function returns NULL for such ref names.
48 * Caps and underscores refers to the special refs, such as HEAD,
49 * FETCH_HEAD and friends, that all live outside of the refs/ directory.
51 #define RESOLVE_REF_READING 0x01
52 #define RESOLVE_REF_NO_RECURSE 0x02
53 #define RESOLVE_REF_ALLOW_BAD_NAME 0x04
55 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
56 unsigned char *sha1, int *flags);
58 char *resolve_refdup(const char *refname, int resolve_flags,
59 unsigned char *sha1, int *flags);
61 int read_ref_full(const char *refname, int resolve_flags,
62 unsigned char *sha1, int *flags);
63 int read_ref(const char *refname, unsigned char *sha1);
65 int ref_exists(const char *refname);
67 int should_autocreate_reflog(const char *refname);
69 int is_branch(const char *refname);
71 extern int refs_init_db(struct strbuf *err);
74 * If refname is a non-symbolic reference that refers to a tag object,
75 * and the tag can be (recursively) dereferenced to a non-tag object,
76 * store the SHA1 of the referred-to object to sha1 and return 0. If
77 * any of these conditions are not met, return a non-zero value.
78 * Symbolic references are considered unpeelable, even if they
79 * ultimately resolve to a peelable tag.
81 int peel_ref(const char *refname, unsigned char *sha1);
83 /**
84 * Resolve refname in the nested "gitlink" repository in the specified
85 * submodule (which must be non-NULL). If the resolution is
86 * successful, return 0 and set sha1 to the name of the object;
87 * otherwise, return a non-zero value.
89 int resolve_gitlink_ref(const char *submodule, const char *refname,
90 unsigned char *sha1);
93 * Return true iff abbrev_name is a possible abbreviation for
94 * full_name according to the rules defined by ref_rev_parse_rules in
95 * refs.c.
97 int refname_match(const char *abbrev_name, const char *full_name);
99 int expand_ref(const char *str, int len, unsigned char *sha1, char **ref);
100 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
101 int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
104 * A ref_transaction represents a collection of ref updates
105 * that should succeed or fail together.
107 * Calling sequence
108 * ----------------
109 * - Allocate and initialize a `struct ref_transaction` by calling
110 * `ref_transaction_begin()`.
112 * - List intended ref updates by calling functions like
113 * `ref_transaction_update()` and `ref_transaction_create()`.
115 * - Call `ref_transaction_commit()` to execute the transaction.
116 * If this succeeds, the ref updates will have taken place and
117 * the transaction cannot be rolled back.
119 * - Instead of `ref_transaction_commit`, use
120 * `initial_ref_transaction_commit()` if the ref database is known
121 * to be empty (e.g. during clone). This is likely to be much
122 * faster.
124 * - At any time call `ref_transaction_free()` to discard the
125 * transaction and free associated resources. In particular,
126 * this rolls back the transaction if it has not been
127 * successfully committed.
129 * Error handling
130 * --------------
132 * On error, transaction functions append a message about what
133 * went wrong to the 'err' argument. The message mentions what
134 * ref was being updated (if any) when the error occurred so it
135 * can be passed to 'die' or 'error' as-is.
137 * The message is appended to err without first clearing err.
138 * err will not be '\n' terminated.
140 * Caveats
141 * -------
143 * Note that no locks are taken, and no refs are read, until
144 * `ref_transaction_commit` is called. So `ref_transaction_verify`
145 * won't report a verification failure until the commit is attempted.
147 struct ref_transaction;
150 * Bit values set in the flags argument passed to each_ref_fn() and
151 * stored in ref_iterator::flags. Other bits are for internal use
152 * only:
155 /* Reference is a symbolic reference. */
156 #define REF_ISSYMREF 0x01
158 /* Reference is a packed reference. */
159 #define REF_ISPACKED 0x02
162 * Reference cannot be resolved to an object name: dangling symbolic
163 * reference (directly or indirectly), corrupt reference file,
164 * reference exists but name is bad, or symbolic reference refers to
165 * ill-formatted reference name.
167 #define REF_ISBROKEN 0x04
170 * Reference name is not well formed.
172 * See git-check-ref-format(1) for the definition of well formed ref names.
174 #define REF_BAD_NAME 0x08
177 * The signature for the callback function for the for_each_*()
178 * functions below. The memory pointed to by the refname and sha1
179 * arguments is only guaranteed to be valid for the duration of a
180 * single callback invocation.
182 typedef int each_ref_fn(const char *refname,
183 const struct object_id *oid, int flags, void *cb_data);
186 * The following functions invoke the specified callback function for
187 * each reference indicated. If the function ever returns a nonzero
188 * value, stop the iteration and return that value. Please note that
189 * it is not safe to modify references while an iteration is in
190 * progress, unless the same callback function invocation that
191 * modifies the reference also returns a nonzero value to immediately
192 * stop the iteration.
194 int head_ref(each_ref_fn fn, void *cb_data);
195 int for_each_ref(each_ref_fn fn, void *cb_data);
196 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data);
197 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data,
198 unsigned int broken);
199 int for_each_tag_ref(each_ref_fn fn, void *cb_data);
200 int for_each_branch_ref(each_ref_fn fn, void *cb_data);
201 int for_each_remote_ref(each_ref_fn fn, void *cb_data);
202 int for_each_replace_ref(each_ref_fn fn, void *cb_data);
203 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data);
204 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
205 const char *prefix, void *cb_data);
207 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
208 int for_each_ref_submodule(const char *submodule,
209 each_ref_fn fn, void *cb_data);
210 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
211 each_ref_fn fn, void *cb_data);
212 int for_each_tag_ref_submodule(const char *submodule,
213 each_ref_fn fn, void *cb_data);
214 int for_each_branch_ref_submodule(const char *submodule,
215 each_ref_fn fn, void *cb_data);
216 int for_each_remote_ref_submodule(const char *submodule,
217 each_ref_fn fn, void *cb_data);
219 int head_ref_namespaced(each_ref_fn fn, void *cb_data);
220 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data);
222 /* can be used to learn about broken ref and symref */
223 int for_each_rawref(each_ref_fn fn, void *cb_data);
225 static inline const char *has_glob_specials(const char *pattern)
227 return strpbrk(pattern, "?*[");
230 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname);
231 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt,
232 const struct string_list *refnames);
235 * Flags for controlling behaviour of pack_refs()
236 * PACK_REFS_PRUNE: Prune loose refs after packing
237 * PACK_REFS_ALL: Pack _all_ refs, not just tags and already packed refs
239 #define PACK_REFS_PRUNE 0x0001
240 #define PACK_REFS_ALL 0x0002
243 * Write a packed-refs file for the current repository.
244 * flags: Combination of the above PACK_REFS_* flags.
246 int pack_refs(unsigned int flags);
249 * Flags controlling ref_transaction_update(), ref_transaction_create(), etc.
250 * REF_NODEREF: act on the ref directly, instead of dereferencing
251 * symbolic references.
253 * Other flags are reserved for internal use.
255 #define REF_NODEREF 0x01
256 #define REF_FORCE_CREATE_REFLOG 0x40
259 * Setup reflog before using. Fill in err and return -1 on failure.
261 int safe_create_reflog(const char *refname, int force_create, struct strbuf *err);
263 /** Reads log for the value of ref during at_time. **/
264 int read_ref_at(const char *refname, unsigned int flags,
265 unsigned long at_time, int cnt,
266 unsigned char *sha1, char **msg,
267 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt);
269 /** Check if a particular reflog exists */
270 int reflog_exists(const char *refname);
273 * Delete the specified reference. If old_sha1 is non-NULL, then
274 * verify that the current value of the reference is old_sha1 before
275 * deleting it. If old_sha1 is NULL, delete the reference if it
276 * exists, regardless of its old value. It is an error for old_sha1 to
277 * be NULL_SHA1. flags is passed through to ref_transaction_delete().
279 int delete_ref(const char *refname, const unsigned char *old_sha1,
280 unsigned int flags);
283 * Delete the specified references. If there are any problems, emit
284 * errors but attempt to keep going (i.e., the deletes are not done in
285 * an all-or-nothing transaction). flags is passed through to
286 * ref_transaction_delete().
288 int delete_refs(struct string_list *refnames, unsigned int flags);
290 /** Delete a reflog */
291 int delete_reflog(const char *refname);
293 /* iterate over reflog entries */
294 typedef int each_reflog_ent_fn(
295 unsigned char *old_sha1, unsigned char *new_sha1,
296 const char *committer, unsigned long timestamp,
297 int tz, const char *msg, void *cb_data);
299 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data);
300 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data);
303 * Calls the specified function for each reflog file until it returns nonzero,
304 * and returns the value
306 int for_each_reflog(each_ref_fn fn, void *cb_data);
308 #define REFNAME_ALLOW_ONELEVEL 1
309 #define REFNAME_REFSPEC_PATTERN 2
312 * Return 0 iff refname has the correct format for a refname according
313 * to the rules described in Documentation/git-check-ref-format.txt.
314 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level
315 * reference names. If REFNAME_REFSPEC_PATTERN is set in flags, then
316 * allow a single "*" wildcard character in the refspec. No leading or
317 * repeated slashes are accepted.
319 int check_refname_format(const char *refname, int flags);
321 const char *prettify_refname(const char *refname);
323 char *shorten_unambiguous_ref(const char *refname, int strict);
325 /** rename ref, return 0 on success **/
326 int rename_ref(const char *oldref, const char *newref, const char *logmsg);
328 int create_symref(const char *refname, const char *target, const char *logmsg);
331 * Update HEAD of the specified gitdir.
332 * Similar to create_symref("relative-git-dir/HEAD", target, NULL), but
333 * this can update the main working tree's HEAD regardless of where
334 * $GIT_DIR points to.
335 * Return 0 if successful, non-zero otherwise.
336 * */
337 int set_worktree_head_symref(const char *gitdir, const char *target);
339 enum action_on_err {
340 UPDATE_REFS_MSG_ON_ERR,
341 UPDATE_REFS_DIE_ON_ERR,
342 UPDATE_REFS_QUIET_ON_ERR
346 * Begin a reference transaction. The reference transaction must
347 * be freed by calling ref_transaction_free().
349 struct ref_transaction *ref_transaction_begin(struct strbuf *err);
352 * Reference transaction updates
354 * The following four functions add a reference check or update to a
355 * ref_transaction. They have some common similar parameters:
357 * transaction -- a pointer to an open ref_transaction, obtained
358 * from ref_transaction_begin().
360 * refname -- the name of the reference to be affected.
362 * flags -- flags affecting the update, passed to
363 * update_ref_lock(). Can be REF_NODEREF, which means that
364 * symbolic references should not be followed.
366 * msg -- a message describing the change (for the reflog).
368 * err -- a strbuf for receiving a description of any error that
369 * might have occurred.
371 * The functions make internal copies of refname and msg, so the
372 * caller retains ownership of these parameters.
374 * The functions return 0 on success and non-zero on failure. A
375 * failure means that the transaction as a whole has failed and needs
376 * to be rolled back.
380 * Add a reference update to transaction. new_sha1 is the value that
381 * the reference should have after the update, or null_sha1 if it
382 * should be deleted. If new_sha1 is NULL, then the reference is not
383 * changed at all. old_sha1 is the value that the reference must have
384 * before the update, or null_sha1 if it must not have existed
385 * beforehand. The old value is checked after the lock is taken to
386 * prevent races. If the old value doesn't agree with old_sha1, the
387 * whole transaction fails. If old_sha1 is NULL, then the previous
388 * value is not checked.
390 * See the above comment "Reference transaction updates" for more
391 * information.
393 int ref_transaction_update(struct ref_transaction *transaction,
394 const char *refname,
395 const unsigned char *new_sha1,
396 const unsigned char *old_sha1,
397 unsigned int flags, const char *msg,
398 struct strbuf *err);
401 * Add a reference creation to transaction. new_sha1 is the value that
402 * the reference should have after the update; it must not be
403 * null_sha1. It is verified that the reference does not exist
404 * already.
406 * See the above comment "Reference transaction updates" for more
407 * information.
409 int ref_transaction_create(struct ref_transaction *transaction,
410 const char *refname,
411 const unsigned char *new_sha1,
412 unsigned int flags, const char *msg,
413 struct strbuf *err);
416 * Add a reference deletion to transaction. If old_sha1 is non-NULL,
417 * then it holds the value that the reference should have had before
418 * the update (which must not be null_sha1).
420 * See the above comment "Reference transaction updates" for more
421 * information.
423 int ref_transaction_delete(struct ref_transaction *transaction,
424 const char *refname,
425 const unsigned char *old_sha1,
426 unsigned int flags, const char *msg,
427 struct strbuf *err);
430 * Verify, within a transaction, that refname has the value old_sha1,
431 * or, if old_sha1 is null_sha1, then verify that the reference
432 * doesn't exist. old_sha1 must be non-NULL.
434 * See the above comment "Reference transaction updates" for more
435 * information.
437 int ref_transaction_verify(struct ref_transaction *transaction,
438 const char *refname,
439 const unsigned char *old_sha1,
440 unsigned int flags,
441 struct strbuf *err);
444 * Commit all of the changes that have been queued in transaction, as
445 * atomically as possible.
447 * Returns 0 for success, or one of the below error codes for errors.
449 /* Naming conflict (for example, the ref names A and A/B conflict). */
450 #define TRANSACTION_NAME_CONFLICT -1
451 /* All other errors. */
452 #define TRANSACTION_GENERIC_ERROR -2
453 int ref_transaction_commit(struct ref_transaction *transaction,
454 struct strbuf *err);
457 * Like ref_transaction_commit(), but optimized for creating
458 * references when originally initializing a repository (e.g., by "git
459 * clone"). It writes the new references directly to packed-refs
460 * without locking the individual references.
462 * It is a bug to call this function when there might be other
463 * processes accessing the repository or if there are existing
464 * references that might conflict with the ones being created. All
465 * old_sha1 values must either be absent or NULL_SHA1.
467 int initial_ref_transaction_commit(struct ref_transaction *transaction,
468 struct strbuf *err);
471 * Free an existing transaction and all associated data.
473 void ref_transaction_free(struct ref_transaction *transaction);
476 * Lock, update, and unlock a single reference. This function
477 * basically does a transaction containing a single call to
478 * ref_transaction_update(). The parameters to this function have the
479 * same meaning as the corresponding parameters to
480 * ref_transaction_update(). Handle errors as requested by the `onerr`
481 * argument.
483 int update_ref(const char *msg, const char *refname,
484 const unsigned char *new_sha1, const unsigned char *old_sha1,
485 unsigned int flags, enum action_on_err onerr);
486 int update_ref_oid(const char *msg, const char *refname,
487 const struct object_id *new_oid, const struct object_id *old_oid,
488 unsigned int flags, enum action_on_err onerr);
490 int parse_hide_refs_config(const char *var, const char *value, const char *);
493 * Check whether a ref is hidden. If no namespace is set, both the first and
494 * the second parameter point to the full ref name. If a namespace is set and
495 * the ref is inside that namespace, the first parameter is a pointer to the
496 * name of the ref with the namespace prefix removed. If a namespace is set and
497 * the ref is outside that namespace, the first parameter is NULL. The second
498 * parameter always points to the full ref name.
500 int ref_is_hidden(const char *, const char *);
502 enum ref_type {
503 REF_TYPE_PER_WORKTREE,
504 REF_TYPE_PSEUDOREF,
505 REF_TYPE_NORMAL,
508 enum ref_type ref_type(const char *refname);
510 enum expire_reflog_flags {
511 EXPIRE_REFLOGS_DRY_RUN = 1 << 0,
512 EXPIRE_REFLOGS_UPDATE_REF = 1 << 1,
513 EXPIRE_REFLOGS_VERBOSE = 1 << 2,
514 EXPIRE_REFLOGS_REWRITE = 1 << 3
518 * The following interface is used for reflog expiration. The caller
519 * calls reflog_expire(), supplying it with three callback functions,
520 * of the following types. The callback functions define the
521 * expiration policy that is desired.
523 * reflog_expiry_prepare_fn -- Called once after the reference is
524 * locked.
526 * reflog_expiry_should_prune_fn -- Called once for each entry in the
527 * existing reflog. It should return true iff that entry should be
528 * pruned.
530 * reflog_expiry_cleanup_fn -- Called once before the reference is
531 * unlocked again.
533 typedef void reflog_expiry_prepare_fn(const char *refname,
534 const unsigned char *sha1,
535 void *cb_data);
536 typedef int reflog_expiry_should_prune_fn(unsigned char *osha1,
537 unsigned char *nsha1,
538 const char *email,
539 unsigned long timestamp, int tz,
540 const char *message, void *cb_data);
541 typedef void reflog_expiry_cleanup_fn(void *cb_data);
544 * Expire reflog entries for the specified reference. sha1 is the old
545 * value of the reference. flags is a combination of the constants in
546 * enum expire_reflog_flags. The three function pointers are described
547 * above. On success, return zero.
549 int reflog_expire(const char *refname, const unsigned char *sha1,
550 unsigned int flags,
551 reflog_expiry_prepare_fn prepare_fn,
552 reflog_expiry_should_prune_fn should_prune_fn,
553 reflog_expiry_cleanup_fn cleanup_fn,
554 void *policy_cb_data);
556 int ref_storage_backend_exists(const char *name);
558 #endif /* REFS_H */