1#ifndef REFS_H 2#define REFS_H 3 4struct ref_lock { 5 char *ref_name; 6 char *orig_ref_name; 7 struct lock_file *lk; 8 unsigned char old_sha1[20]; 9 int lock_fd; 10 int force_write; 11}; 12 13/* 14 * A ref_transaction represents a collection of ref updates 15 * that should succeed or fail together. 16 * 17 * Calling sequence 18 * ---------------- 19 * - Allocate and initialize a `struct ref_transaction` by calling 20 * `ref_transaction_begin()`. 21 * 22 * - List intended ref updates by calling functions like 23 * `ref_transaction_update()` and `ref_transaction_create()`. 24 * 25 * - Call `ref_transaction_commit()` to execute the transaction. 26 * If this succeeds, the ref updates will have taken place and 27 * the transaction cannot be rolled back. 28 * 29 * - At any time call `ref_transaction_free()` to discard the 30 * transaction and free associated resources. In particular, 31 * this rolls back the transaction if it has not been 32 * successfully committed. 33 * 34 * Error handling 35 * -------------- 36 * 37 * On error, transaction functions append a message about what 38 * went wrong to the 'err' argument. The message mentions what 39 * ref was being updated (if any) when the error occurred so it 40 * can be passed to 'die' or 'error' as-is. 41 * 42 * The message is appended to err without first clearing err. 43 * err will not be '\n' terminated. 44 */ 45struct ref_transaction; 46 47/* 48 * Bit values set in the flags argument passed to each_ref_fn(): 49 */ 50 51/* Reference is a symbolic reference. */ 52#define REF_ISSYMREF 0x01 53 54/* Reference is a packed reference. */ 55#define REF_ISPACKED 0x02 56 57/* 58 * Reference cannot be resolved to an object name: dangling symbolic 59 * reference (directly or indirectly), corrupt reference file, 60 * reference exists but name is bad, or symbolic reference refers to 61 * ill-formatted reference name. 62 */ 63#define REF_ISBROKEN 0x04 64 65/* 66 * Reference name is not well formed. 67 * 68 * See git-check-ref-format(1) for the definition of well formed ref names. 69 */ 70#define REF_BAD_NAME 0x08 71 72/* 73 * The signature for the callback function for the for_each_*() 74 * functions below. The memory pointed to by the refname and sha1 75 * arguments is only guaranteed to be valid for the duration of a 76 * single callback invocation. 77 */ 78typedef int each_ref_fn(const char *refname, 79 const unsigned char *sha1, int flags, void *cb_data); 80 81/* 82 * The following functions invoke the specified callback function for 83 * each reference indicated. If the function ever returns a nonzero 84 * value, stop the iteration and return that value. Please note that 85 * it is not safe to modify references while an iteration is in 86 * progress, unless the same callback function invocation that 87 * modifies the reference also returns a nonzero value to immediately 88 * stop the iteration. 89 */ 90extern int head_ref(each_ref_fn, void *); 91extern int for_each_ref(each_ref_fn, void *); 92extern int for_each_ref_in(const char *, each_ref_fn, void *); 93extern int for_each_tag_ref(each_ref_fn, void *); 94extern int for_each_branch_ref(each_ref_fn, void *); 95extern int for_each_remote_ref(each_ref_fn, void *); 96extern int for_each_replace_ref(each_ref_fn, void *); 97extern int for_each_glob_ref(each_ref_fn, const char *pattern, void *); 98extern int for_each_glob_ref_in(each_ref_fn, const char *pattern, const char* prefix, void *); 99 100extern int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 101extern int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 102extern int for_each_ref_in_submodule(const char *submodule, const char *prefix, 103 each_ref_fn fn, void *cb_data); 104extern int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 105extern int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 106extern int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 107 108extern int head_ref_namespaced(each_ref_fn fn, void *cb_data); 109extern int for_each_namespaced_ref(each_ref_fn fn, void *cb_data); 110 111static inline const char *has_glob_specials(const char *pattern) 112{ 113 return strpbrk(pattern, "?*["); 114} 115 116/* can be used to learn about broken ref and symref */ 117extern int for_each_rawref(each_ref_fn, void *); 118 119extern void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname); 120extern void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames); 121 122/* 123 * Lock the packed-refs file for writing. Flags is passed to 124 * hold_lock_file_for_update(). Return 0 on success. 125 * Errno is set to something meaningful on error. 126 */ 127extern int lock_packed_refs(int flags); 128 129/* 130 * Add a reference to the in-memory packed reference cache. This may 131 * only be called while the packed-refs file is locked (see 132 * lock_packed_refs()). To actually write the packed-refs file, call 133 * commit_packed_refs(). 134 */ 135extern void add_packed_ref(const char *refname, const unsigned char *sha1); 136 137/* 138 * Write the current version of the packed refs cache from memory to 139 * disk. The packed-refs file must already be locked for writing (see 140 * lock_packed_refs()). Return zero on success. 141 * Sets errno to something meaningful on error. 142 */ 143extern int commit_packed_refs(void); 144 145/* 146 * Rollback the lockfile for the packed-refs file, and discard the 147 * in-memory packed reference cache. (The packed-refs file will be 148 * read anew if it is needed again after this function is called.) 149 */ 150extern void rollback_packed_refs(void); 151 152/* 153 * Flags for controlling behaviour of pack_refs() 154 * PACK_REFS_PRUNE: Prune loose refs after packing 155 * PACK_REFS_ALL: Pack _all_ refs, not just tags and already packed refs 156 */ 157#define PACK_REFS_PRUNE 0x0001 158#define PACK_REFS_ALL 0x0002 159 160/* 161 * Write a packed-refs file for the current repository. 162 * flags: Combination of the above PACK_REFS_* flags. 163 */ 164int pack_refs(unsigned int flags); 165 166extern int repack_without_refs(const char **refnames, int n, 167 struct strbuf *err); 168 169extern int ref_exists(const char *); 170 171extern int is_branch(const char *refname); 172 173/* 174 * If refname is a non-symbolic reference that refers to a tag object, 175 * and the tag can be (recursively) dereferenced to a non-tag object, 176 * store the SHA1 of the referred-to object to sha1 and return 0. If 177 * any of these conditions are not met, return a non-zero value. 178 * Symbolic references are considered unpeelable, even if they 179 * ultimately resolve to a peelable tag. 180 */ 181extern int peel_ref(const char *refname, unsigned char *sha1); 182 183/* 184 * Flags controlling lock_any_ref_for_update(), ref_transaction_update(), 185 * ref_transaction_create(), etc. 186 * REF_NODEREF: act on the ref directly, instead of dereferencing 187 * symbolic references. 188 * REF_DELETING: tolerate broken refs 189 * 190 * Flags >= 0x100 are reserved for internal use. 191 */ 192#define REF_NODEREF 0x01 193#define REF_DELETING 0x02 194/* 195 * This function sets errno to something meaningful on failure. 196 */ 197extern struct ref_lock *lock_any_ref_for_update(const char *refname, 198 const unsigned char *old_sha1, 199 int flags, int *type_p); 200 201/** Close the file descriptor owned by a lock and return the status */ 202extern int close_ref(struct ref_lock *lock); 203 204/** Close and commit the ref locked by the lock */ 205extern int commit_ref(struct ref_lock *lock); 206 207/** Release any lock taken but not written. **/ 208extern void unlock_ref(struct ref_lock *lock); 209 210/* 211 * Setup reflog before using. Set errno to something meaningful on failure. 212 */ 213int log_ref_setup(const char *refname, char *logfile, int bufsize); 214 215/** Reads log for the value of ref during at_time. **/ 216extern int read_ref_at(const char *refname, unsigned int flags, 217 unsigned long at_time, int cnt, 218 unsigned char *sha1, char **msg, 219 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt); 220 221/** Check if a particular reflog exists */ 222extern int reflog_exists(const char *refname); 223 224/** Delete a reflog */ 225extern int delete_reflog(const char *refname); 226 227/* iterate over reflog entries */ 228typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *); 229int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data); 230int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data); 231 232/* 233 * Calls the specified function for each reflog file until it returns nonzero, 234 * and returns the value 235 */ 236extern int for_each_reflog(each_ref_fn, void *); 237 238#define REFNAME_ALLOW_ONELEVEL 1 239#define REFNAME_REFSPEC_PATTERN 2 240 241/* 242 * Return 0 iff refname has the correct format for a refname according 243 * to the rules described in Documentation/git-check-ref-format.txt. 244 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level 245 * reference names. If REFNAME_REFSPEC_PATTERN is set in flags, then 246 * allow a "*" wildcard character in place of one of the name 247 * components. No leading or repeated slashes are accepted. 248 */ 249extern int check_refname_format(const char *refname, int flags); 250 251extern const char *prettify_refname(const char *refname); 252extern char *shorten_unambiguous_ref(const char *refname, int strict); 253 254/** rename ref, return 0 on success **/ 255extern int rename_ref(const char *oldref, const char *newref, const char *logmsg); 256 257/** 258 * Resolve refname in the nested "gitlink" repository that is located 259 * at path. If the resolution is successful, return 0 and set sha1 to 260 * the name of the object; otherwise, return a non-zero value. 261 */ 262extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1); 263 264enum action_on_err { 265 UPDATE_REFS_MSG_ON_ERR, 266 UPDATE_REFS_DIE_ON_ERR, 267 UPDATE_REFS_QUIET_ON_ERR 268}; 269 270/* 271 * Begin a reference transaction. The reference transaction must 272 * be freed by calling ref_transaction_free(). 273 */ 274struct ref_transaction *ref_transaction_begin(struct strbuf *err); 275 276/* 277 * The following functions add a reference check or update to a 278 * ref_transaction. In all of them, refname is the name of the 279 * reference to be affected. The functions make internal copies of 280 * refname and msg, so the caller retains ownership of these parameters. 281 * flags can be REF_NODEREF; it is passed to update_ref_lock(). 282 */ 283 284/* 285 * Add a reference update to transaction. new_sha1 is the value that 286 * the reference should have after the update, or null_sha1 if it should 287 * be deleted. If have_old is true, then old_sha1 holds the value 288 * that the reference should have had before the update, or zeros if 289 * it must not have existed beforehand. 290 * Function returns 0 on success and non-zero on failure. A failure to update 291 * means that the transaction as a whole has failed and will need to be 292 * rolled back. 293 */ 294int ref_transaction_update(struct ref_transaction *transaction, 295 const char *refname, 296 const unsigned char *new_sha1, 297 const unsigned char *old_sha1, 298 int flags, int have_old, const char *msg, 299 struct strbuf *err); 300 301/* 302 * Add a reference creation to transaction. new_sha1 is the value 303 * that the reference should have after the update; it must not be the 304 * null SHA-1. It is verified that the reference does not exist 305 * already. 306 * Function returns 0 on success and non-zero on failure. A failure to create 307 * means that the transaction as a whole has failed and will need to be 308 * rolled back. 309 */ 310int ref_transaction_create(struct ref_transaction *transaction, 311 const char *refname, 312 const unsigned char *new_sha1, 313 int flags, const char *msg, 314 struct strbuf *err); 315 316/* 317 * Add a reference deletion to transaction. If have_old is true, then 318 * old_sha1 holds the value that the reference should have had before 319 * the update (which must not be the null SHA-1). 320 * Function returns 0 on success and non-zero on failure. A failure to delete 321 * means that the transaction as a whole has failed and will need to be 322 * rolled back. 323 */ 324int ref_transaction_delete(struct ref_transaction *transaction, 325 const char *refname, 326 const unsigned char *old_sha1, 327 int flags, int have_old, const char *msg, 328 struct strbuf *err); 329 330/* 331 * Commit all of the changes that have been queued in transaction, as 332 * atomically as possible. 333 * 334 * Returns 0 for success, or one of the below error codes for errors. 335 */ 336/* Naming conflict (for example, the ref names A and A/B conflict). */ 337#define TRANSACTION_NAME_CONFLICT -1 338/* All other errors. */ 339#define TRANSACTION_GENERIC_ERROR -2 340int ref_transaction_commit(struct ref_transaction *transaction, 341 struct strbuf *err); 342 343/* 344 * Free an existing transaction and all associated data. 345 */ 346void ref_transaction_free(struct ref_transaction *transaction); 347 348/** Lock a ref and then write its file */ 349int update_ref(const char *action, const char *refname, 350 const unsigned char *sha1, const unsigned char *oldval, 351 int flags, enum action_on_err onerr); 352 353extern int parse_hide_refs_config(const char *var, const char *value, const char *); 354extern int ref_is_hidden(const char *); 355 356enum expire_reflog_flags { 357 EXPIRE_REFLOGS_DRY_RUN = 1 << 0, 358 EXPIRE_REFLOGS_UPDATE_REF = 1 << 1, 359 EXPIRE_REFLOGS_VERBOSE = 1 << 2, 360 EXPIRE_REFLOGS_REWRITE = 1 << 3 361}; 362 363/* 364 * The following interface is used for reflog expiration. The caller 365 * calls reflog_expire(), supplying it with three callback functions, 366 * of the following types. The callback functions define the 367 * expiration policy that is desired. 368 * 369 * reflog_expiry_prepare_fn -- Called once after the reference is 370 * locked. 371 * 372 * reflog_expiry_should_prune_fn -- Called once for each entry in the 373 * existing reflog. It should return true iff that entry should be 374 * pruned. 375 * 376 * reflog_expiry_cleanup_fn -- Called once before the reference is 377 * unlocked again. 378 */ 379typedef void reflog_expiry_prepare_fn(const char *refname, 380 const unsigned char *sha1, 381 void *cb_data); 382typedef int reflog_expiry_should_prune_fn(unsigned char *osha1, 383 unsigned char *nsha1, 384 const char *email, 385 unsigned long timestamp, int tz, 386 const char *message, void *cb_data); 387typedef void reflog_expiry_cleanup_fn(void *cb_data); 388 389/* 390 * Expire reflog entries for the specified reference. sha1 is the old 391 * value of the reference. flags is a combination of the constants in 392 * enum expire_reflog_flags. The three function pointers are described 393 * above. On success, return zero. 394 */ 395extern int reflog_expire(const char *refname, const unsigned char *sha1, 396 unsigned int flags, 397 reflog_expiry_prepare_fn prepare_fn, 398 reflog_expiry_should_prune_fn should_prune_fn, 399 reflog_expiry_cleanup_fn cleanup_fn, 400 void *policy_cb_data); 401 402#endif /* REFS_H */