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 unsigned char *sha1, 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 190 191/* 192 * Setup reflog before using. Set errno to something meaningful on failure. 193 */ 194int log_ref_setup(const char *refname, char *logfile, int bufsize); 195 196/** Reads log for the value of ref during at_time. **/ 197extern int read_ref_at(const char *refname, unsigned int flags, 198 unsigned long at_time, int cnt, 199 unsigned char *sha1, char **msg, 200 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt); 201 202/** Check if a particular reflog exists */ 203extern int reflog_exists(const char *refname); 204 205/** Delete a reflog */ 206extern int delete_reflog(const char *refname); 207 208/* iterate over reflog entries */ 209typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *); 210int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data); 211int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data); 212 213/* 214 * Calls the specified function for each reflog file until it returns nonzero, 215 * and returns the value 216 */ 217extern int for_each_reflog(each_ref_fn, void *); 218 219#define REFNAME_ALLOW_ONELEVEL 1 220#define REFNAME_REFSPEC_PATTERN 2 221 222/* 223 * Return 0 iff refname has the correct format for a refname according 224 * to the rules described in Documentation/git-check-ref-format.txt. 225 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level 226 * reference names. If REFNAME_REFSPEC_PATTERN is set in flags, then 227 * allow a "*" wildcard character in place of one of the name 228 * components. No leading or repeated slashes are accepted. 229 */ 230extern int check_refname_format(const char *refname, int flags); 231 232extern const char *prettify_refname(const char *refname); 233extern char *shorten_unambiguous_ref(const char *refname, int strict); 234 235/** rename ref, return 0 on success **/ 236extern int rename_ref(const char *oldref, const char *newref, const char *logmsg); 237 238/** 239 * Resolve refname in the nested "gitlink" repository that is located 240 * at path. If the resolution is successful, return 0 and set sha1 to 241 * the name of the object; otherwise, return a non-zero value. 242 */ 243extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1); 244 245enum action_on_err { 246 UPDATE_REFS_MSG_ON_ERR, 247 UPDATE_REFS_DIE_ON_ERR, 248 UPDATE_REFS_QUIET_ON_ERR 249}; 250 251/* 252 * Begin a reference transaction. The reference transaction must 253 * be freed by calling ref_transaction_free(). 254 */ 255struct ref_transaction *ref_transaction_begin(struct strbuf *err); 256 257/* 258 * The following functions add a reference check or update to a 259 * ref_transaction. In all of them, refname is the name of the 260 * reference to be affected. The functions make internal copies of 261 * refname and msg, so the caller retains ownership of these parameters. 262 * flags can be REF_NODEREF; it is passed to update_ref_lock(). 263 */ 264 265/* 266 * Add a reference update to transaction. new_sha1 is the value that 267 * the reference should have after the update, or null_sha1 if it 268 * should be deleted. If new_sha1 is NULL, then the reference is not 269 * changed at all. old_sha1 is the value that the reference must have 270 * before the update, or null_sha1 if it must not have existed 271 * beforehand. The old value is checked after the lock is taken to 272 * prevent races. If the old value doesn't agree with old_sha1, the 273 * whole transaction fails. If old_sha1 is NULL, then the previous 274 * value is not checked. 275 * 276 * Return 0 on success and non-zero on failure. Any failure in the 277 * transaction means that the transaction as a whole has failed and 278 * will need to be rolled back. 279 */ 280int ref_transaction_update(struct ref_transaction *transaction, 281 const char *refname, 282 const unsigned char *new_sha1, 283 const unsigned char *old_sha1, 284 unsigned int flags, const char *msg, 285 struct strbuf *err); 286 287/* 288 * Add a reference creation to transaction. new_sha1 is the value 289 * that the reference should have after the update; it must not be the 290 * null SHA-1. It is verified that the reference does not exist 291 * already. 292 * Function returns 0 on success and non-zero on failure. A failure to create 293 * means that the transaction as a whole has failed and will need to be 294 * rolled back. 295 */ 296int ref_transaction_create(struct ref_transaction *transaction, 297 const char *refname, 298 const unsigned char *new_sha1, 299 unsigned int flags, const char *msg, 300 struct strbuf *err); 301 302/* 303 * Add a reference deletion to transaction. If old_sha1 is non-NULL, then 304 * it holds the value that the reference should have had before 305 * the update (which must not be the null SHA-1). 306 * Function returns 0 on success and non-zero on failure. A failure to delete 307 * means that the transaction as a whole has failed and will need to be 308 * rolled back. 309 */ 310int ref_transaction_delete(struct ref_transaction *transaction, 311 const char *refname, 312 const unsigned char *old_sha1, 313 unsigned int flags, const char *msg, 314 struct strbuf *err); 315 316/* 317 * Verify, within a transaction, that refname has the value old_sha1, 318 * or, if old_sha1 is null_sha1, then verify that the reference 319 * doesn't exist. old_sha1 must be non-NULL. Function returns 0 on 320 * success and non-zero on failure. A failure to verify means that the 321 * transaction as a whole has failed and will need to be rolled back. 322 */ 323int ref_transaction_verify(struct ref_transaction *transaction, 324 const char *refname, 325 const unsigned char *old_sha1, 326 unsigned int flags, 327 struct strbuf *err); 328 329/* 330 * Commit all of the changes that have been queued in transaction, as 331 * atomically as possible. 332 * 333 * Returns 0 for success, or one of the below error codes for errors. 334 */ 335/* Naming conflict (for example, the ref names A and A/B conflict). */ 336#define TRANSACTION_NAME_CONFLICT -1 337/* All other errors. */ 338#define TRANSACTION_GENERIC_ERROR -2 339int ref_transaction_commit(struct ref_transaction *transaction, 340 struct strbuf *err); 341 342/* 343 * Free an existing transaction and all associated data. 344 */ 345void ref_transaction_free(struct ref_transaction *transaction); 346 347/** Lock a ref and then write its file */ 348int update_ref(const char *action, const char *refname, 349 const unsigned char *sha1, const unsigned char *oldval, 350 unsigned int flags, enum action_on_err onerr); 351 352extern int parse_hide_refs_config(const char *var, const char *value, const char *); 353extern int ref_is_hidden(const char *); 354 355enum expire_reflog_flags { 356 EXPIRE_REFLOGS_DRY_RUN = 1 << 0, 357 EXPIRE_REFLOGS_UPDATE_REF = 1 << 1, 358 EXPIRE_REFLOGS_VERBOSE = 1 << 2, 359 EXPIRE_REFLOGS_REWRITE = 1 << 3 360}; 361 362/* 363 * The following interface is used for reflog expiration. The caller 364 * calls reflog_expire(), supplying it with three callback functions, 365 * of the following types. The callback functions define the 366 * expiration policy that is desired. 367 * 368 * reflog_expiry_prepare_fn -- Called once after the reference is 369 * locked. 370 * 371 * reflog_expiry_should_prune_fn -- Called once for each entry in the 372 * existing reflog. It should return true iff that entry should be 373 * pruned. 374 * 375 * reflog_expiry_cleanup_fn -- Called once before the reference is 376 * unlocked again. 377 */ 378typedef void reflog_expiry_prepare_fn(const char *refname, 379 const unsigned char *sha1, 380 void *cb_data); 381typedef int reflog_expiry_should_prune_fn(unsigned char *osha1, 382 unsigned char *nsha1, 383 const char *email, 384 unsigned long timestamp, int tz, 385 const char *message, void *cb_data); 386typedef void reflog_expiry_cleanup_fn(void *cb_data); 387 388/* 389 * Expire reflog entries for the specified reference. sha1 is the old 390 * value of the reference. flags is a combination of the constants in 391 * enum expire_reflog_flags. The three function pointers are described 392 * above. On success, return zero. 393 */ 394extern int reflog_expire(const char *refname, const unsigned char *sha1, 395 unsigned int flags, 396 reflog_expiry_prepare_fn prepare_fn, 397 reflog_expiry_should_prune_fn should_prune_fn, 398 reflog_expiry_cleanup_fn cleanup_fn, 399 void *policy_cb_data); 400 401#endif /* REFS_H */