Git 2.7.2
[git/gitweb.git] / refs.h
blob7a040774890637253847e82e3ea3a90ac081f757
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 extern const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
56 unsigned char *sha1, int *flags);
58 extern char *resolve_refdup(const char *refname, int resolve_flags,
59 unsigned char *sha1, int *flags);
61 extern int read_ref_full(const char *refname, int resolve_flags,
62 unsigned char *sha1, int *flags);
63 extern int read_ref(const char *refname, unsigned char *sha1);
65 extern int ref_exists(const char *refname);
67 extern int is_branch(const char *refname);
70 * If refname is a non-symbolic reference that refers to a tag object,
71 * and the tag can be (recursively) dereferenced to a non-tag object,
72 * store the SHA1 of the referred-to object to sha1 and return 0. If
73 * any of these conditions are not met, return a non-zero value.
74 * Symbolic references are considered unpeelable, even if they
75 * ultimately resolve to a peelable tag.
77 extern int peel_ref(const char *refname, unsigned char *sha1);
79 /**
80 * Resolve refname in the nested "gitlink" repository that is located
81 * at path. If the resolution is successful, return 0 and set sha1 to
82 * the name of the object; otherwise, return a non-zero value.
84 extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1);
87 * Return true iff abbrev_name is a possible abbreviation for
88 * full_name according to the rules defined by ref_rev_parse_rules in
89 * refs.c.
91 extern int refname_match(const char *abbrev_name, const char *full_name);
93 extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
94 extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
97 * A ref_transaction represents a collection of ref updates
98 * that should succeed or fail together.
100 * Calling sequence
101 * ----------------
102 * - Allocate and initialize a `struct ref_transaction` by calling
103 * `ref_transaction_begin()`.
105 * - List intended ref updates by calling functions like
106 * `ref_transaction_update()` and `ref_transaction_create()`.
108 * - Call `ref_transaction_commit()` to execute the transaction.
109 * If this succeeds, the ref updates will have taken place and
110 * the transaction cannot be rolled back.
112 * - At any time call `ref_transaction_free()` to discard the
113 * transaction and free associated resources. In particular,
114 * this rolls back the transaction if it has not been
115 * successfully committed.
117 * Error handling
118 * --------------
120 * On error, transaction functions append a message about what
121 * went wrong to the 'err' argument. The message mentions what
122 * ref was being updated (if any) when the error occurred so it
123 * can be passed to 'die' or 'error' as-is.
125 * The message is appended to err without first clearing err.
126 * err will not be '\n' terminated.
128 struct ref_transaction;
131 * Bit values set in the flags argument passed to each_ref_fn():
134 /* Reference is a symbolic reference. */
135 #define REF_ISSYMREF 0x01
137 /* Reference is a packed reference. */
138 #define REF_ISPACKED 0x02
141 * Reference cannot be resolved to an object name: dangling symbolic
142 * reference (directly or indirectly), corrupt reference file,
143 * reference exists but name is bad, or symbolic reference refers to
144 * ill-formatted reference name.
146 #define REF_ISBROKEN 0x04
149 * Reference name is not well formed.
151 * See git-check-ref-format(1) for the definition of well formed ref names.
153 #define REF_BAD_NAME 0x08
156 * The signature for the callback function for the for_each_*()
157 * functions below. The memory pointed to by the refname and sha1
158 * arguments is only guaranteed to be valid for the duration of a
159 * single callback invocation.
161 typedef int each_ref_fn(const char *refname,
162 const struct object_id *oid, int flags, void *cb_data);
165 * The following functions invoke the specified callback function for
166 * each reference indicated. If the function ever returns a nonzero
167 * value, stop the iteration and return that value. Please note that
168 * it is not safe to modify references while an iteration is in
169 * progress, unless the same callback function invocation that
170 * modifies the reference also returns a nonzero value to immediately
171 * stop the iteration.
173 extern int head_ref(each_ref_fn fn, void *cb_data);
174 extern int for_each_ref(each_ref_fn fn, void *cb_data);
175 extern int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data);
176 extern int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken);
177 extern int for_each_tag_ref(each_ref_fn fn, void *cb_data);
178 extern int for_each_branch_ref(each_ref_fn fn, void *cb_data);
179 extern int for_each_remote_ref(each_ref_fn fn, void *cb_data);
180 extern int for_each_replace_ref(each_ref_fn fn, void *cb_data);
181 extern int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data);
182 extern int for_each_glob_ref_in(each_ref_fn fn, const char *pattern, const char *prefix, void *cb_data);
184 extern int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
185 extern int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
186 extern int for_each_ref_in_submodule(const char *submodule, const char *prefix,
187 each_ref_fn fn, void *cb_data);
188 extern int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
189 extern int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
190 extern int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
192 extern int head_ref_namespaced(each_ref_fn fn, void *cb_data);
193 extern int for_each_namespaced_ref(each_ref_fn fn, void *cb_data);
195 /* can be used to learn about broken ref and symref */
196 extern int for_each_rawref(each_ref_fn fn, void *cb_data);
198 static inline const char *has_glob_specials(const char *pattern)
200 return strpbrk(pattern, "?*[");
203 extern void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname);
204 extern void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames);
207 * Flags for controlling behaviour of pack_refs()
208 * PACK_REFS_PRUNE: Prune loose refs after packing
209 * PACK_REFS_ALL: Pack _all_ refs, not just tags and already packed refs
211 #define PACK_REFS_PRUNE 0x0001
212 #define PACK_REFS_ALL 0x0002
215 * Write a packed-refs file for the current repository.
216 * flags: Combination of the above PACK_REFS_* flags.
218 int pack_refs(unsigned int flags);
221 * Flags controlling ref_transaction_update(), ref_transaction_create(), etc.
222 * REF_NODEREF: act on the ref directly, instead of dereferencing
223 * symbolic references.
225 * Other flags are reserved for internal use.
227 #define REF_NODEREF 0x01
228 #define REF_FORCE_CREATE_REFLOG 0x40
231 * Setup reflog before using. Fill in err and return -1 on failure.
233 int safe_create_reflog(const char *refname, int force_create, struct strbuf *err);
235 /** Reads log for the value of ref during at_time. **/
236 extern int read_ref_at(const char *refname, unsigned int flags,
237 unsigned long at_time, int cnt,
238 unsigned char *sha1, char **msg,
239 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt);
241 /** Check if a particular reflog exists */
242 extern int reflog_exists(const char *refname);
245 * Delete the specified reference. If old_sha1 is non-NULL, then
246 * verify that the current value of the reference is old_sha1 before
247 * deleting it. If old_sha1 is NULL, delete the reference if it
248 * exists, regardless of its old value. It is an error for old_sha1 to
249 * be NULL_SHA1. flags is passed through to ref_transaction_delete().
251 extern int delete_ref(const char *refname, const unsigned char *old_sha1,
252 unsigned int flags);
255 * Delete the specified references. If there are any problems, emit
256 * errors but attempt to keep going (i.e., the deletes are not done in
257 * an all-or-nothing transaction).
259 extern int delete_refs(struct string_list *refnames);
261 /** Delete a reflog */
262 extern int delete_reflog(const char *refname);
264 /* iterate over reflog entries */
265 typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *);
266 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data);
267 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data);
270 * Calls the specified function for each reflog file until it returns nonzero,
271 * and returns the value
273 extern int for_each_reflog(each_ref_fn, void *);
275 #define REFNAME_ALLOW_ONELEVEL 1
276 #define REFNAME_REFSPEC_PATTERN 2
279 * Return 0 iff refname has the correct format for a refname according
280 * to the rules described in Documentation/git-check-ref-format.txt.
281 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level
282 * reference names. If REFNAME_REFSPEC_PATTERN is set in flags, then
283 * allow a single "*" wildcard character in the refspec. No leading or
284 * repeated slashes are accepted.
286 extern int check_refname_format(const char *refname, int flags);
288 extern const char *prettify_refname(const char *refname);
290 extern char *shorten_unambiguous_ref(const char *refname, int strict);
292 /** rename ref, return 0 on success **/
293 extern int rename_ref(const char *oldref, const char *newref, const char *logmsg);
295 extern int create_symref(const char *ref, const char *refs_heads_master, const char *logmsg);
297 enum action_on_err {
298 UPDATE_REFS_MSG_ON_ERR,
299 UPDATE_REFS_DIE_ON_ERR,
300 UPDATE_REFS_QUIET_ON_ERR
304 * Begin a reference transaction. The reference transaction must
305 * be freed by calling ref_transaction_free().
307 struct ref_transaction *ref_transaction_begin(struct strbuf *err);
310 * Reference transaction updates
312 * The following four functions add a reference check or update to a
313 * ref_transaction. They have some common similar parameters:
315 * transaction -- a pointer to an open ref_transaction, obtained
316 * from ref_transaction_begin().
318 * refname -- the name of the reference to be affected.
320 * flags -- flags affecting the update, passed to
321 * update_ref_lock(). Can be REF_NODEREF, which means that
322 * symbolic references should not be followed.
324 * msg -- a message describing the change (for the reflog).
326 * err -- a strbuf for receiving a description of any error that
327 * might have occured.
329 * The functions make internal copies of refname and msg, so the
330 * caller retains ownership of these parameters.
332 * The functions return 0 on success and non-zero on failure. A
333 * failure means that the transaction as a whole has failed and needs
334 * to be rolled back.
338 * Add a reference update to transaction. new_sha1 is the value that
339 * the reference should have after the update, or null_sha1 if it
340 * should be deleted. If new_sha1 is NULL, then the reference is not
341 * changed at all. old_sha1 is the value that the reference must have
342 * before the update, or null_sha1 if it must not have existed
343 * beforehand. The old value is checked after the lock is taken to
344 * prevent races. If the old value doesn't agree with old_sha1, the
345 * whole transaction fails. If old_sha1 is NULL, then the previous
346 * value is not checked.
348 * See the above comment "Reference transaction updates" for more
349 * information.
351 int ref_transaction_update(struct ref_transaction *transaction,
352 const char *refname,
353 const unsigned char *new_sha1,
354 const unsigned char *old_sha1,
355 unsigned int flags, const char *msg,
356 struct strbuf *err);
359 * Add a reference creation to transaction. new_sha1 is the value that
360 * the reference should have after the update; it must not be
361 * null_sha1. It is verified that the reference does not exist
362 * already.
364 * See the above comment "Reference transaction updates" for more
365 * information.
367 int ref_transaction_create(struct ref_transaction *transaction,
368 const char *refname,
369 const unsigned char *new_sha1,
370 unsigned int flags, const char *msg,
371 struct strbuf *err);
374 * Add a reference deletion to transaction. If old_sha1 is non-NULL,
375 * then it holds the value that the reference should have had before
376 * the update (which must not be null_sha1).
378 * See the above comment "Reference transaction updates" for more
379 * information.
381 int ref_transaction_delete(struct ref_transaction *transaction,
382 const char *refname,
383 const unsigned char *old_sha1,
384 unsigned int flags, const char *msg,
385 struct strbuf *err);
388 * Verify, within a transaction, that refname has the value old_sha1,
389 * or, if old_sha1 is null_sha1, then verify that the reference
390 * doesn't exist. old_sha1 must be non-NULL.
392 * See the above comment "Reference transaction updates" for more
393 * information.
395 int ref_transaction_verify(struct ref_transaction *transaction,
396 const char *refname,
397 const unsigned char *old_sha1,
398 unsigned int flags,
399 struct strbuf *err);
402 * Commit all of the changes that have been queued in transaction, as
403 * atomically as possible.
405 * Returns 0 for success, or one of the below error codes for errors.
407 /* Naming conflict (for example, the ref names A and A/B conflict). */
408 #define TRANSACTION_NAME_CONFLICT -1
409 /* All other errors. */
410 #define TRANSACTION_GENERIC_ERROR -2
411 int ref_transaction_commit(struct ref_transaction *transaction,
412 struct strbuf *err);
415 * Like ref_transaction_commit(), but optimized for creating
416 * references when originally initializing a repository (e.g., by "git
417 * clone"). It writes the new references directly to packed-refs
418 * without locking the individual references.
420 * It is a bug to call this function when there might be other
421 * processes accessing the repository or if there are existing
422 * references that might conflict with the ones being created. All
423 * old_sha1 values must either be absent or NULL_SHA1.
425 int initial_ref_transaction_commit(struct ref_transaction *transaction,
426 struct strbuf *err);
429 * Free an existing transaction and all associated data.
431 void ref_transaction_free(struct ref_transaction *transaction);
434 * Lock, update, and unlock a single reference. This function
435 * basically does a transaction containing a single call to
436 * ref_transaction_update(). The parameters to this function have the
437 * same meaning as the corresponding parameters to
438 * ref_transaction_update(). Handle errors as requested by the `onerr`
439 * argument.
441 int update_ref(const char *msg, const char *refname,
442 const unsigned char *new_sha1, const unsigned char *old_sha1,
443 unsigned int flags, enum action_on_err onerr);
445 extern int parse_hide_refs_config(const char *var, const char *value, const char *);
448 * Check whether a ref is hidden. If no namespace is set, both the first and
449 * the second parameter point to the full ref name. If a namespace is set and
450 * the ref is inside that namespace, the first parameter is a pointer to the
451 * name of the ref with the namespace prefix removed. If a namespace is set and
452 * the ref is outside that namespace, the first parameter is NULL. The second
453 * parameter always points to the full ref name.
455 extern int ref_is_hidden(const char *, const char *);
457 enum ref_type {
458 REF_TYPE_PER_WORKTREE,
459 REF_TYPE_PSEUDOREF,
460 REF_TYPE_NORMAL,
463 enum ref_type ref_type(const char *refname);
465 enum expire_reflog_flags {
466 EXPIRE_REFLOGS_DRY_RUN = 1 << 0,
467 EXPIRE_REFLOGS_UPDATE_REF = 1 << 1,
468 EXPIRE_REFLOGS_VERBOSE = 1 << 2,
469 EXPIRE_REFLOGS_REWRITE = 1 << 3
473 * The following interface is used for reflog expiration. The caller
474 * calls reflog_expire(), supplying it with three callback functions,
475 * of the following types. The callback functions define the
476 * expiration policy that is desired.
478 * reflog_expiry_prepare_fn -- Called once after the reference is
479 * locked.
481 * reflog_expiry_should_prune_fn -- Called once for each entry in the
482 * existing reflog. It should return true iff that entry should be
483 * pruned.
485 * reflog_expiry_cleanup_fn -- Called once before the reference is
486 * unlocked again.
488 typedef void reflog_expiry_prepare_fn(const char *refname,
489 const unsigned char *sha1,
490 void *cb_data);
491 typedef int reflog_expiry_should_prune_fn(unsigned char *osha1,
492 unsigned char *nsha1,
493 const char *email,
494 unsigned long timestamp, int tz,
495 const char *message, void *cb_data);
496 typedef void reflog_expiry_cleanup_fn(void *cb_data);
499 * Expire reflog entries for the specified reference. sha1 is the old
500 * value of the reference. flags is a combination of the constants in
501 * enum expire_reflog_flags. The three function pointers are described
502 * above. On success, return zero.
504 extern int reflog_expire(const char *refname, const unsigned char *sha1,
505 unsigned int flags,
506 reflog_expiry_prepare_fn prepare_fn,
507 reflog_expiry_should_prune_fn should_prune_fn,
508 reflog_expiry_cleanup_fn cleanup_fn,
509 void *policy_cb_data);
511 #endif /* REFS_H */