submodule: prevent backslash expantion in submodule names
[git/git.git] / refs.h
1 #ifndef REFS_H
2 #define REFS_H
3
4 /*
5 * Resolve a reference, recursively following symbolic refererences.
6 *
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.
11 *
12 * If the reference cannot be resolved to an object, the behavior
13 * depends on the RESOLVE_REF_READING flag:
14 *
15 * - If RESOLVE_REF_READING is set, return NULL.
16 *
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.
22 *
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.
27 *
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.
35 *
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.
39 *
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.
44 *
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.
50 */
51 #define RESOLVE_REF_READING 0x01
52 #define RESOLVE_REF_NO_RECURSE 0x02
53 #define RESOLVE_REF_ALLOW_BAD_NAME 0x04
54
55 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
56 unsigned char *sha1, int *flags);
57
58 char *resolve_refdup(const char *refname, int resolve_flags,
59 unsigned char *sha1, int *flags);
60
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);
64
65 int ref_exists(const char *refname);
66
67 int should_autocreate_reflog(const char *refname);
68
69 int is_branch(const char *refname);
70
71 extern int refs_init_db(struct strbuf *err);
72
73 /*
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.
80 */
81 int peel_ref(const char *refname, unsigned char *sha1);
82
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.
88 */
89 int resolve_gitlink_ref(const char *submodule, const char *refname,
90 unsigned char *sha1);
91
92 /*
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.
96 */
97 int refname_match(const char *abbrev_name, const char *full_name);
98
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);
102
103 /*
104 * A ref_transaction represents a collection of ref updates
105 * that should succeed or fail together.
106 *
107 * Calling sequence
108 * ----------------
109 * - Allocate and initialize a `struct ref_transaction` by calling
110 * `ref_transaction_begin()`.
111 *
112 * - List intended ref updates by calling functions like
113 * `ref_transaction_update()` and `ref_transaction_create()`.
114 *
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.
118 *
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.
123 *
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.
128 *
129 * Error handling
130 * --------------
131 *
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.
136 *
137 * The message is appended to err without first clearing err.
138 * err will not be '\n' terminated.
139 *
140 * Caveats
141 * -------
142 *
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.
146 */
147 struct ref_transaction;
148
149 /*
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:
153 */
154
155 /* Reference is a symbolic reference. */
156 #define REF_ISSYMREF 0x01
157
158 /* Reference is a packed reference. */
159 #define REF_ISPACKED 0x02
160
161 /*
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.
166 */
167 #define REF_ISBROKEN 0x04
168
169 /*
170 * Reference name is not well formed.
171 *
172 * See git-check-ref-format(1) for the definition of well formed ref names.
173 */
174 #define REF_BAD_NAME 0x08
175
176 /*
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.
181 */
182 typedef int each_ref_fn(const char *refname,
183 const struct object_id *oid, int flags, void *cb_data);
184
185 /*
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.
193 */
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);
206
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);
218
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);
221
222 /* can be used to learn about broken ref and symref */
223 int for_each_rawref(each_ref_fn fn, void *cb_data);
224
225 static inline const char *has_glob_specials(const char *pattern)
226 {
227 return strpbrk(pattern, "?*[");
228 }
229
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);
233
234 /*
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
238 */
239 #define PACK_REFS_PRUNE 0x0001
240 #define PACK_REFS_ALL 0x0002
241
242 /*
243 * Write a packed-refs file for the current repository.
244 * flags: Combination of the above PACK_REFS_* flags.
245 */
246 int pack_refs(unsigned int flags);
247
248 /*
249 * Flags controlling ref_transaction_update(), ref_transaction_create(), etc.
250 * REF_NODEREF: act on the ref directly, instead of dereferencing
251 * symbolic references.
252 *
253 * Other flags are reserved for internal use.
254 */
255 #define REF_NODEREF 0x01
256 #define REF_FORCE_CREATE_REFLOG 0x40
257
258 /*
259 * Setup reflog before using. Fill in err and return -1 on failure.
260 */
261 int safe_create_reflog(const char *refname, int force_create, struct strbuf *err);
262
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);
268
269 /** Check if a particular reflog exists */
270 int reflog_exists(const char *refname);
271
272 /*
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().
278 */
279 int delete_ref(const char *msg, const char *refname,
280 const unsigned char *old_sha1, unsigned int flags);
281
282 /*
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().
287 */
288 int delete_refs(struct string_list *refnames, unsigned int flags);
289
290 /** Delete a reflog */
291 int delete_reflog(const char *refname);
292
293 /* iterate over reflog entries */
294 typedef int each_reflog_ent_fn(
295 struct object_id *old_oid, struct object_id *new_oid,
296 const char *committer, unsigned long timestamp,
297 int tz, const char *msg, void *cb_data);
298
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);
301
302 /*
303 * Calls the specified function for each reflog file until it returns nonzero,
304 * and returns the value
305 */
306 int for_each_reflog(each_ref_fn fn, void *cb_data);
307
308 #define REFNAME_ALLOW_ONELEVEL 1
309 #define REFNAME_REFSPEC_PATTERN 2
310
311 /*
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.
318 */
319 int check_refname_format(const char *refname, int flags);
320
321 const char *prettify_refname(const char *refname);
322
323 char *shorten_unambiguous_ref(const char *refname, int strict);
324
325 /** rename ref, return 0 on success **/
326 int rename_ref(const char *oldref, const char *newref, const char *logmsg);
327
328 int create_symref(const char *refname, const char *target, const char *logmsg);
329
330 /*
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,
338 const char *logmsg);
339
340 enum action_on_err {
341 UPDATE_REFS_MSG_ON_ERR,
342 UPDATE_REFS_DIE_ON_ERR,
343 UPDATE_REFS_QUIET_ON_ERR
344 };
345
346 /*
347 * Begin a reference transaction. The reference transaction must
348 * be freed by calling ref_transaction_free().
349 */
350 struct ref_transaction *ref_transaction_begin(struct strbuf *err);
351
352 /*
353 * Reference transaction updates
354 *
355 * The following four functions add a reference check or update to a
356 * ref_transaction. They have some common similar parameters:
357 *
358 * transaction -- a pointer to an open ref_transaction, obtained
359 * from ref_transaction_begin().
360 *
361 * refname -- the name of the reference to be affected.
362 *
363 * flags -- flags affecting the update, passed to
364 * update_ref_lock(). Can be REF_NODEREF, which means that
365 * symbolic references should not be followed.
366 *
367 * msg -- a message describing the change (for the reflog).
368 *
369 * err -- a strbuf for receiving a description of any error that
370 * might have occurred.
371 *
372 * The functions make internal copies of refname and msg, so the
373 * caller retains ownership of these parameters.
374 *
375 * The functions return 0 on success and non-zero on failure. A
376 * failure means that the transaction as a whole has failed and needs
377 * to be rolled back.
378 */
379
380 /*
381 * Add a reference update to transaction. new_sha1 is the value that
382 * the reference should have after the update, or null_sha1 if it
383 * should be deleted. If new_sha1 is NULL, then the reference is not
384 * changed at all. old_sha1 is the value that the reference must have
385 * before the update, or null_sha1 if it must not have existed
386 * beforehand. The old value is checked after the lock is taken to
387 * prevent races. If the old value doesn't agree with old_sha1, the
388 * whole transaction fails. If old_sha1 is NULL, then the previous
389 * value is not checked.
390 *
391 * See the above comment "Reference transaction updates" for more
392 * information.
393 */
394 int ref_transaction_update(struct ref_transaction *transaction,
395 const char *refname,
396 const unsigned char *new_sha1,
397 const unsigned char *old_sha1,
398 unsigned int flags, const char *msg,
399 struct strbuf *err);
400
401 /*
402 * Add a reference creation to transaction. new_sha1 is the value that
403 * the reference should have after the update; it must not be
404 * null_sha1. It is verified that the reference does not exist
405 * already.
406 *
407 * See the above comment "Reference transaction updates" for more
408 * information.
409 */
410 int ref_transaction_create(struct ref_transaction *transaction,
411 const char *refname,
412 const unsigned char *new_sha1,
413 unsigned int flags, const char *msg,
414 struct strbuf *err);
415
416 /*
417 * Add a reference deletion to transaction. If old_sha1 is non-NULL,
418 * then it holds the value that the reference should have had before
419 * the update (which must not be null_sha1).
420 *
421 * See the above comment "Reference transaction updates" for more
422 * information.
423 */
424 int ref_transaction_delete(struct ref_transaction *transaction,
425 const char *refname,
426 const unsigned char *old_sha1,
427 unsigned int flags, const char *msg,
428 struct strbuf *err);
429
430 /*
431 * Verify, within a transaction, that refname has the value old_sha1,
432 * or, if old_sha1 is null_sha1, then verify that the reference
433 * doesn't exist. old_sha1 must be non-NULL.
434 *
435 * See the above comment "Reference transaction updates" for more
436 * information.
437 */
438 int ref_transaction_verify(struct ref_transaction *transaction,
439 const char *refname,
440 const unsigned char *old_sha1,
441 unsigned int flags,
442 struct strbuf *err);
443
444 /*
445 * Commit all of the changes that have been queued in transaction, as
446 * atomically as possible.
447 *
448 * Returns 0 for success, or one of the below error codes for errors.
449 */
450 /* Naming conflict (for example, the ref names A and A/B conflict). */
451 #define TRANSACTION_NAME_CONFLICT -1
452 /* All other errors. */
453 #define TRANSACTION_GENERIC_ERROR -2
454 int ref_transaction_commit(struct ref_transaction *transaction,
455 struct strbuf *err);
456
457 /*
458 * Like ref_transaction_commit(), but optimized for creating
459 * references when originally initializing a repository (e.g., by "git
460 * clone"). It writes the new references directly to packed-refs
461 * without locking the individual references.
462 *
463 * It is a bug to call this function when there might be other
464 * processes accessing the repository or if there are existing
465 * references that might conflict with the ones being created. All
466 * old_sha1 values must either be absent or NULL_SHA1.
467 */
468 int initial_ref_transaction_commit(struct ref_transaction *transaction,
469 struct strbuf *err);
470
471 /*
472 * Free an existing transaction and all associated data.
473 */
474 void ref_transaction_free(struct ref_transaction *transaction);
475
476 /**
477 * Lock, update, and unlock a single reference. This function
478 * basically does a transaction containing a single call to
479 * ref_transaction_update(). The parameters to this function have the
480 * same meaning as the corresponding parameters to
481 * ref_transaction_update(). Handle errors as requested by the `onerr`
482 * argument.
483 */
484 int update_ref(const char *msg, const char *refname,
485 const unsigned char *new_sha1, const unsigned char *old_sha1,
486 unsigned int flags, enum action_on_err onerr);
487 int update_ref_oid(const char *msg, const char *refname,
488 const struct object_id *new_oid, const struct object_id *old_oid,
489 unsigned int flags, enum action_on_err onerr);
490
491 int parse_hide_refs_config(const char *var, const char *value, const char *);
492
493 /*
494 * Check whether a ref is hidden. If no namespace is set, both the first and
495 * the second parameter point to the full ref name. If a namespace is set and
496 * the ref is inside that namespace, the first parameter is a pointer to the
497 * name of the ref with the namespace prefix removed. If a namespace is set and
498 * the ref is outside that namespace, the first parameter is NULL. The second
499 * parameter always points to the full ref name.
500 */
501 int ref_is_hidden(const char *, const char *);
502
503 enum ref_type {
504 REF_TYPE_PER_WORKTREE,
505 REF_TYPE_PSEUDOREF,
506 REF_TYPE_NORMAL,
507 };
508
509 enum ref_type ref_type(const char *refname);
510
511 enum expire_reflog_flags {
512 EXPIRE_REFLOGS_DRY_RUN = 1 << 0,
513 EXPIRE_REFLOGS_UPDATE_REF = 1 << 1,
514 EXPIRE_REFLOGS_VERBOSE = 1 << 2,
515 EXPIRE_REFLOGS_REWRITE = 1 << 3
516 };
517
518 /*
519 * The following interface is used for reflog expiration. The caller
520 * calls reflog_expire(), supplying it with three callback functions,
521 * of the following types. The callback functions define the
522 * expiration policy that is desired.
523 *
524 * reflog_expiry_prepare_fn -- Called once after the reference is
525 * locked.
526 *
527 * reflog_expiry_should_prune_fn -- Called once for each entry in the
528 * existing reflog. It should return true iff that entry should be
529 * pruned.
530 *
531 * reflog_expiry_cleanup_fn -- Called once before the reference is
532 * unlocked again.
533 */
534 typedef void reflog_expiry_prepare_fn(const char *refname,
535 const unsigned char *sha1,
536 void *cb_data);
537 typedef int reflog_expiry_should_prune_fn(unsigned char *osha1,
538 unsigned char *nsha1,
539 const char *email,
540 unsigned long timestamp, int tz,
541 const char *message, void *cb_data);
542 typedef void reflog_expiry_cleanup_fn(void *cb_data);
543
544 /*
545 * Expire reflog entries for the specified reference. sha1 is the old
546 * value of the reference. flags is a combination of the constants in
547 * enum expire_reflog_flags. The three function pointers are described
548 * above. On success, return zero.
549 */
550 int reflog_expire(const char *refname, const unsigned char *sha1,
551 unsigned int flags,
552 reflog_expiry_prepare_fn prepare_fn,
553 reflog_expiry_should_prune_fn should_prune_fn,
554 reflog_expiry_cleanup_fn cleanup_fn,
555 void *policy_cb_data);
556
557 int ref_storage_backend_exists(const char *name);
558
559 #endif /* REFS_H */