1#ifndef REFS_H 2#define REFS_H 3 4/* 5 * A ref_transaction represents a collection of ref updates 6 * that should succeed or fail together. 7 * 8 * Calling sequence 9 * ---------------- 10 * - Allocate and initialize a `struct ref_transaction` by calling 11 * `ref_transaction_begin()`. 12 * 13 * - List intended ref updates by calling functions like 14 * `ref_transaction_update()` and `ref_transaction_create()`. 15 * 16 * - Call `ref_transaction_commit()` to execute the transaction. 17 * If this succeeds, the ref updates will have taken place and 18 * the transaction cannot be rolled back. 19 * 20 * - At any time call `ref_transaction_free()` to discard the 21 * transaction and free associated resources. In particular, 22 * this rolls back the transaction if it has not been 23 * successfully committed. 24 * 25 * Error handling 26 * -------------- 27 * 28 * On error, transaction functions append a message about what 29 * went wrong to the 'err' argument. The message mentions what 30 * ref was being updated (if any) when the error occurred so it 31 * can be passed to 'die' or 'error' as-is. 32 * 33 * The message is appended to err without first clearing err. 34 * err will not be '\n' terminated. 35 */ 36struct ref_transaction; 37 38/* 39 * Bit values set in the flags argument passed to each_ref_fn(): 40 */ 41 42/* Reference is a symbolic reference. */ 43#define REF_ISSYMREF 0x01 44 45/* Reference is a packed reference. */ 46#define REF_ISPACKED 0x02 47 48/* 49 * Reference cannot be resolved to an object name: dangling symbolic 50 * reference (directly or indirectly), corrupt reference file, 51 * reference exists but name is bad, or symbolic reference refers to 52 * ill-formatted reference name. 53 */ 54#define REF_ISBROKEN 0x04 55 56/* 57 * Reference name is not well formed. 58 * 59 * See git-check-ref-format(1) for the definition of well formed ref names. 60 */ 61#define REF_BAD_NAME 0x08 62 63/* 64 * The signature for the callback function for the for_each_*() 65 * functions below. The memory pointed to by the refname and sha1 66 * arguments is only guaranteed to be valid for the duration of a 67 * single callback invocation. 68 */ 69typedef int each_ref_fn(const char *refname, 70 const struct object_id *oid, int flags, void *cb_data); 71 72/* 73 * The following functions invoke the specified callback function for 74 * each reference indicated. If the function ever returns a nonzero 75 * value, stop the iteration and return that value. Please note that 76 * it is not safe to modify references while an iteration is in 77 * progress, unless the same callback function invocation that 78 * modifies the reference also returns a nonzero value to immediately 79 * stop the iteration. 80 */ 81extern int head_ref(each_ref_fn, void *); 82extern int for_each_ref(each_ref_fn, void *); 83extern int for_each_ref_in(const char *, each_ref_fn, void *); 84extern int for_each_tag_ref(each_ref_fn, void *); 85extern int for_each_branch_ref(each_ref_fn, void *); 86extern int for_each_remote_ref(each_ref_fn, void *); 87extern int for_each_replace_ref(each_ref_fn, void *); 88extern int for_each_glob_ref(each_ref_fn, const char *pattern, void *); 89extern int for_each_glob_ref_in(each_ref_fn, const char *pattern, const char* prefix, void *); 90 91extern int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 92extern int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 93extern int for_each_ref_in_submodule(const char *submodule, const char *prefix, 94 each_ref_fn fn, void *cb_data); 95extern int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 96extern int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 97extern int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 98 99extern int head_ref_namespaced(each_ref_fn fn, void *cb_data); 100extern int for_each_namespaced_ref(each_ref_fn fn, void *cb_data); 101 102static inline const char *has_glob_specials(const char *pattern) 103{ 104 return strpbrk(pattern, "?*["); 105} 106 107/* can be used to learn about broken ref and symref */ 108extern int for_each_rawref(each_ref_fn, void *); 109 110extern void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname); 111extern void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames); 112 113/* 114 * Lock the packed-refs file for writing. Flags is passed to 115 * hold_lock_file_for_update(). Return 0 on success. 116 * Errno is set to something meaningful on error. 117 */ 118extern int lock_packed_refs(int flags); 119 120/* 121 * Add a reference to the in-memory packed reference cache. This may 122 * only be called while the packed-refs file is locked (see 123 * lock_packed_refs()). To actually write the packed-refs file, call 124 * commit_packed_refs(). 125 */ 126extern void add_packed_ref(const char *refname, const unsigned char *sha1); 127 128/* 129 * Write the current version of the packed refs cache from memory to 130 * disk. The packed-refs file must already be locked for writing (see 131 * lock_packed_refs()). Return zero on success. 132 * Sets errno to something meaningful on error. 133 */ 134extern int commit_packed_refs(void); 135 136/* 137 * Rollback the lockfile for the packed-refs file, and discard the 138 * in-memory packed reference cache. (The packed-refs file will be 139 * read anew if it is needed again after this function is called.) 140 */ 141extern void rollback_packed_refs(void); 142 143/* 144 * Flags for controlling behaviour of pack_refs() 145 * PACK_REFS_PRUNE: Prune loose refs after packing 146 * PACK_REFS_ALL: Pack _all_ refs, not just tags and already packed refs 147 */ 148#define PACK_REFS_PRUNE 0x0001 149#define PACK_REFS_ALL 0x0002 150 151/* 152 * Write a packed-refs file for the current repository. 153 * flags: Combination of the above PACK_REFS_* flags. 154 */ 155int pack_refs(unsigned int flags); 156 157/* 158 * Rewrite the packed-refs file, omitting any refs listed in 159 * 'refnames'. On error, packed-refs will be unchanged, the return 160 * value is nonzero, and a message about the error is written to the 161 * 'err' strbuf. 162 * 163 * The refs in 'refnames' needn't be sorted. `err` must not be NULL. 164 */ 165extern int repack_without_refs(struct string_list *refnames, 166 struct strbuf *err); 167 168extern int ref_exists(const char *); 169 170extern int is_branch(const char *refname); 171 172/* 173 * If refname is a non-symbolic reference that refers to a tag object, 174 * and the tag can be (recursively) dereferenced to a non-tag object, 175 * store the SHA1 of the referred-to object to sha1 and return 0. If 176 * any of these conditions are not met, return a non-zero value. 177 * Symbolic references are considered unpeelable, even if they 178 * ultimately resolve to a peelable tag. 179 */ 180extern int peel_ref(const char *refname, unsigned char *sha1); 181 182/* 183 * Flags controlling ref_transaction_update(), ref_transaction_create(), etc. 184 * REF_NODEREF: act on the ref directly, instead of dereferencing 185 * symbolic references. 186 * 187 * Other flags are reserved for internal use. 188 */ 189#define REF_NODEREF 0x01 190#define REF_FORCE_CREATE_REFLOG 0x40 191 192/* 193 * Setup reflog before using. Fill in err and return -1 on failure. 194 */ 195int safe_create_reflog(const char *refname, int force_create, struct strbuf *err); 196 197/** Reads log for the value of ref during at_time. **/ 198extern int read_ref_at(const char *refname, unsigned int flags, 199 unsigned long at_time, int cnt, 200 unsigned char *sha1, char **msg, 201 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt); 202 203/** Check if a particular reflog exists */ 204extern int reflog_exists(const char *refname); 205 206/** Delete a reflog */ 207extern int delete_reflog(const char *refname); 208 209/* iterate over reflog entries */ 210typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *); 211int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data); 212int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data); 213 214/* 215 * Calls the specified function for each reflog file until it returns nonzero, 216 * and returns the value 217 */ 218extern int for_each_reflog(each_ref_fn, void *); 219 220#define REFNAME_ALLOW_ONELEVEL 1 221#define REFNAME_REFSPEC_PATTERN 2 222 223/* 224 * Return 0 iff refname has the correct format for a refname according 225 * to the rules described in Documentation/git-check-ref-format.txt. 226 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level 227 * reference names. If REFNAME_REFSPEC_PATTERN is set in flags, then 228 * allow a "*" wildcard character in place of one of the name 229 * components. No leading or repeated slashes are accepted. 230 */ 231extern int check_refname_format(const char *refname, int flags); 232 233extern const char *prettify_refname(const char *refname); 234extern char *shorten_unambiguous_ref(const char *refname, int strict); 235 236/** rename ref, return 0 on success **/ 237extern int rename_ref(const char *oldref, const char *newref, const char *logmsg); 238 239/** 240 * Resolve refname in the nested "gitlink" repository that is located 241 * at path. If the resolution is successful, return 0 and set sha1 to 242 * the name of the object; otherwise, return a non-zero value. 243 */ 244extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1); 245 246enum action_on_err { 247 UPDATE_REFS_MSG_ON_ERR, 248 UPDATE_REFS_DIE_ON_ERR, 249 UPDATE_REFS_QUIET_ON_ERR 250}; 251 252/* 253 * Begin a reference transaction. The reference transaction must 254 * be freed by calling ref_transaction_free(). 255 */ 256struct ref_transaction *ref_transaction_begin(struct strbuf *err); 257 258/* 259 * Reference transaction updates 260 * 261 * The following four functions add a reference check or update to a 262 * ref_transaction. They have some common similar parameters: 263 * 264 * transaction -- a pointer to an open ref_transaction, obtained 265 * from ref_transaction_begin(). 266 * 267 * refname -- the name of the reference to be affected. 268 * 269 * flags -- flags affecting the update, passed to 270 * update_ref_lock(). Can be REF_NODEREF, which means that 271 * symbolic references should not be followed. 272 * 273 * msg -- a message describing the change (for the reflog). 274 * 275 * err -- a strbuf for receiving a description of any error that 276 * might have occured. 277 * 278 * The functions make internal copies of refname and msg, so the 279 * caller retains ownership of these parameters. 280 * 281 * The functions return 0 on success and non-zero on failure. A 282 * failure means that the transaction as a whole has failed and needs 283 * to be rolled back. 284 */ 285 286/* 287 * Add a reference update to transaction. new_sha1 is the value that 288 * the reference should have after the update, or null_sha1 if it 289 * should be deleted. If new_sha1 is NULL, then the reference is not 290 * changed at all. old_sha1 is the value that the reference must have 291 * before the update, or null_sha1 if it must not have existed 292 * beforehand. The old value is checked after the lock is taken to 293 * prevent races. If the old value doesn't agree with old_sha1, the 294 * whole transaction fails. If old_sha1 is NULL, then the previous 295 * value is not checked. 296 * 297 * See the above comment "Reference transaction updates" for more 298 * information. 299 */ 300int ref_transaction_update(struct ref_transaction *transaction, 301 const char *refname, 302 const unsigned char *new_sha1, 303 const unsigned char *old_sha1, 304 unsigned int flags, const char *msg, 305 struct strbuf *err); 306 307/* 308 * Add a reference creation to transaction. new_sha1 is the value that 309 * the reference should have after the update; it must not be 310 * null_sha1. It is verified that the reference does not exist 311 * already. 312 * 313 * See the above comment "Reference transaction updates" for more 314 * information. 315 */ 316int ref_transaction_create(struct ref_transaction *transaction, 317 const char *refname, 318 const unsigned char *new_sha1, 319 unsigned int flags, const char *msg, 320 struct strbuf *err); 321 322/* 323 * Add a reference deletion to transaction. If old_sha1 is non-NULL, 324 * then it holds the value that the reference should have had before 325 * the update (which must not be null_sha1). 326 * 327 * See the above comment "Reference transaction updates" for more 328 * information. 329 */ 330int ref_transaction_delete(struct ref_transaction *transaction, 331 const char *refname, 332 const unsigned char *old_sha1, 333 unsigned int flags, const char *msg, 334 struct strbuf *err); 335 336/* 337 * Verify, within a transaction, that refname has the value old_sha1, 338 * or, if old_sha1 is null_sha1, then verify that the reference 339 * doesn't exist. old_sha1 must be non-NULL. 340 * 341 * See the above comment "Reference transaction updates" for more 342 * information. 343 */ 344int ref_transaction_verify(struct ref_transaction *transaction, 345 const char *refname, 346 const unsigned char *old_sha1, 347 unsigned int flags, 348 struct strbuf *err); 349 350/* 351 * Commit all of the changes that have been queued in transaction, as 352 * atomically as possible. 353 * 354 * Returns 0 for success, or one of the below error codes for errors. 355 */ 356/* Naming conflict (for example, the ref names A and A/B conflict). */ 357#define TRANSACTION_NAME_CONFLICT -1 358/* All other errors. */ 359#define TRANSACTION_GENERIC_ERROR -2 360int ref_transaction_commit(struct ref_transaction *transaction, 361 struct strbuf *err); 362 363/* 364 * Free an existing transaction and all associated data. 365 */ 366void ref_transaction_free(struct ref_transaction *transaction); 367 368/** 369 * Lock, update, and unlock a single reference. This function 370 * basically does a transaction containing a single call to 371 * ref_transaction_update(). The parameters to this function have the 372 * same meaning as the corresponding parameters to 373 * ref_transaction_update(). Handle errors as requested by the `onerr` 374 * argument. 375 */ 376int update_ref(const char *msg, const char *refname, 377 const unsigned char *new_sha1, const unsigned char *old_sha1, 378 unsigned int flags, enum action_on_err onerr); 379 380extern int parse_hide_refs_config(const char *var, const char *value, const char *); 381extern int ref_is_hidden(const char *); 382 383enum expire_reflog_flags { 384 EXPIRE_REFLOGS_DRY_RUN = 1 << 0, 385 EXPIRE_REFLOGS_UPDATE_REF = 1 << 1, 386 EXPIRE_REFLOGS_VERBOSE = 1 << 2, 387 EXPIRE_REFLOGS_REWRITE = 1 << 3 388}; 389 390/* 391 * The following interface is used for reflog expiration. The caller 392 * calls reflog_expire(), supplying it with three callback functions, 393 * of the following types. The callback functions define the 394 * expiration policy that is desired. 395 * 396 * reflog_expiry_prepare_fn -- Called once after the reference is 397 * locked. 398 * 399 * reflog_expiry_should_prune_fn -- Called once for each entry in the 400 * existing reflog. It should return true iff that entry should be 401 * pruned. 402 * 403 * reflog_expiry_cleanup_fn -- Called once before the reference is 404 * unlocked again. 405 */ 406typedef void reflog_expiry_prepare_fn(const char *refname, 407 const unsigned char *sha1, 408 void *cb_data); 409typedef int reflog_expiry_should_prune_fn(unsigned char *osha1, 410 unsigned char *nsha1, 411 const char *email, 412 unsigned long timestamp, int tz, 413 const char *message, void *cb_data); 414typedef void reflog_expiry_cleanup_fn(void *cb_data); 415 416/* 417 * Expire reflog entries for the specified reference. sha1 is the old 418 * value of the reference. flags is a combination of the constants in 419 * enum expire_reflog_flags. The three function pointers are described 420 * above. On success, return zero. 421 */ 422extern int reflog_expire(const char *refname, const unsigned char *sha1, 423 unsigned int flags, 424 reflog_expiry_prepare_fn prepare_fn, 425 reflog_expiry_should_prune_fn should_prune_fn, 426 reflog_expiry_cleanup_fn cleanup_fn, 427 void *policy_cb_data); 428 429#endif /* REFS_H */