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, or 60 * symbolic reference refers to ill-formatted reference name. 61 */ 62#define REF_ISBROKEN 0x04 63 64/* 65 * The signature for the callback function for the for_each_*() 66 * functions below. The memory pointed to by the refname and sha1 67 * arguments is only guaranteed to be valid for the duration of a 68 * single callback invocation. 69 */ 70typedef int each_ref_fn(const char *refname, 71 const unsigned char *sha1, int flags, void *cb_data); 72 73/* 74 * The following functions invoke the specified callback function for 75 * each reference indicated. If the function ever returns a nonzero 76 * value, stop the iteration and return that value. Please note that 77 * it is not safe to modify references while an iteration is in 78 * progress, unless the same callback function invocation that 79 * modifies the reference also returns a nonzero value to immediately 80 * stop the iteration. 81 */ 82extern int head_ref(each_ref_fn, void *); 83extern int for_each_ref(each_ref_fn, void *); 84extern int for_each_ref_in(const char *, each_ref_fn, void *); 85extern int for_each_tag_ref(each_ref_fn, void *); 86extern int for_each_branch_ref(each_ref_fn, void *); 87extern int for_each_remote_ref(each_ref_fn, void *); 88extern int for_each_replace_ref(each_ref_fn, void *); 89extern int for_each_glob_ref(each_ref_fn, const char *pattern, void *); 90extern int for_each_glob_ref_in(each_ref_fn, const char *pattern, const char* prefix, void *); 91 92extern int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 93extern int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 94extern int for_each_ref_in_submodule(const char *submodule, const char *prefix, 95 each_ref_fn fn, void *cb_data); 96extern int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 97extern int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 98extern int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data); 99 100extern int head_ref_namespaced(each_ref_fn fn, void *cb_data); 101extern int for_each_namespaced_ref(each_ref_fn fn, void *cb_data); 102 103static inline const char *has_glob_specials(const char *pattern) 104{ 105 return strpbrk(pattern, "?*["); 106} 107 108/* can be used to learn about broken ref and symref */ 109extern int for_each_rawref(each_ref_fn, void *); 110 111extern void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname); 112extern void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list* refnames); 113 114/* 115 * Lock the packed-refs file for writing. Flags is passed to 116 * hold_lock_file_for_update(). Return 0 on success. 117 * Errno is set to something meaningful on error. 118 */ 119extern int lock_packed_refs(int flags); 120 121/* 122 * Add a reference to the in-memory packed reference cache. This may 123 * only be called while the packed-refs file is locked (see 124 * lock_packed_refs()). To actually write the packed-refs file, call 125 * commit_packed_refs(). 126 */ 127extern void add_packed_ref(const char *refname, const unsigned char *sha1); 128 129/* 130 * Write the current version of the packed refs cache from memory to 131 * disk. The packed-refs file must already be locked for writing (see 132 * lock_packed_refs()). Return zero on success. 133 * Sets errno to something meaningful on error. 134 */ 135extern int commit_packed_refs(void); 136 137/* 138 * Rollback the lockfile for the packed-refs file, and discard the 139 * in-memory packed reference cache. (The packed-refs file will be 140 * read anew if it is needed again after this function is called.) 141 */ 142extern void rollback_packed_refs(void); 143 144/* 145 * Flags for controlling behaviour of pack_refs() 146 * PACK_REFS_PRUNE: Prune loose refs after packing 147 * PACK_REFS_ALL: Pack _all_ refs, not just tags and already packed refs 148 */ 149#define PACK_REFS_PRUNE 0x0001 150#define PACK_REFS_ALL 0x0002 151 152/* 153 * Write a packed-refs file for the current repository. 154 * flags: Combination of the above PACK_REFS_* flags. 155 */ 156int pack_refs(unsigned int flags); 157 158extern int repack_without_refs(const char **refnames, int n, 159 struct strbuf *err); 160 161extern int ref_exists(const char *); 162 163/* 164 * If refname is a non-symbolic reference that refers to a tag object, 165 * and the tag can be (recursively) dereferenced to a non-tag object, 166 * store the SHA1 of the referred-to object to sha1 and return 0. If 167 * any of these conditions are not met, return a non-zero value. 168 * Symbolic references are considered unpeelable, even if they 169 * ultimately resolve to a peelable tag. 170 */ 171extern int peel_ref(const char *refname, unsigned char *sha1); 172 173/** Locks any ref (for 'HEAD' type refs). */ 174#define REF_NODEREF 0x01 175/* errno is set to something meaningful on failure */ 176extern struct ref_lock *lock_any_ref_for_update(const char *refname, 177 const unsigned char *old_sha1, 178 int flags, int *type_p); 179 180/** Close the file descriptor owned by a lock and return the status */ 181extern int close_ref(struct ref_lock *lock); 182 183/** Close and commit the ref locked by the lock */ 184extern int commit_ref(struct ref_lock *lock); 185 186/** Release any lock taken but not written. **/ 187extern void unlock_ref(struct ref_lock *lock); 188 189/** Writes sha1 into the ref specified by the lock. **/ 190extern int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1, const char *msg); 191 192/* 193 * Setup reflog before using. Set errno to something meaningful on failure. 194 */ 195int log_ref_setup(const char *refname, char *logfile, int bufsize); 196 197/** Reads log for the value of ref during at_time. **/ 198extern int read_ref_at(const char *refname, 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#define REFNAME_DOT_COMPONENT 4 222 223/* 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. If 230 * REFNAME_DOT_COMPONENT is set in flags, then allow refname 231 * components to start with "." (but not a whole component equal to 232 * "." or ".."). 233 */ 234extern int check_refname_format(const char *refname, int flags); 235 236extern const char *prettify_refname(const char *refname); 237extern char *shorten_unambiguous_ref(const char *refname, int strict); 238 239/** rename ref, return 0 on success **/ 240extern int rename_ref(const char *oldref, const char *newref, const char *logmsg); 241 242/** 243 * Resolve refname in the nested "gitlink" repository that is located 244 * at path. If the resolution is successful, return 0 and set sha1 to 245 * the name of the object; otherwise, return a non-zero value. 246 */ 247extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1); 248 249enum action_on_err { 250 UPDATE_REFS_MSG_ON_ERR, 251 UPDATE_REFS_DIE_ON_ERR, 252 UPDATE_REFS_QUIET_ON_ERR 253}; 254 255/* 256 * Begin a reference transaction. The reference transaction must 257 * be freed by calling ref_transaction_free(). 258 */ 259struct ref_transaction *ref_transaction_begin(struct strbuf *err); 260 261/* 262 * The following functions add a reference check or update to a 263 * ref_transaction. In all of them, refname is the name of the 264 * reference to be affected. The functions make internal copies of 265 * refname, so the caller retains ownership of the parameter. flags 266 * can be REF_NODEREF; it is passed to update_ref_lock(). 267 */ 268 269/* 270 * Add a reference update to transaction. new_sha1 is the value that 271 * the reference should have after the update, or zeros if it should 272 * be deleted. If have_old is true, then old_sha1 holds the value 273 * that the reference should have had before the update, or zeros if 274 * it must not have existed beforehand. 275 * Function returns 0 on success and non-zero on failure. A failure to update 276 * means that the transaction as a whole has failed and will need to be 277 * rolled back. 278 */ 279int ref_transaction_update(struct ref_transaction *transaction, 280 const char *refname, 281 const unsigned char *new_sha1, 282 const unsigned char *old_sha1, 283 int flags, int have_old, 284 struct strbuf *err); 285 286/* 287 * Add a reference creation to transaction. new_sha1 is the value 288 * that the reference should have after the update; it must not be the 289 * null SHA-1. It is verified that the reference does not exist 290 * already. 291 * Function returns 0 on success and non-zero on failure. A failure to create 292 * means that the transaction as a whole has failed and will need to be 293 * rolled back. 294 */ 295int ref_transaction_create(struct ref_transaction *transaction, 296 const char *refname, 297 const unsigned char *new_sha1, 298 int flags, 299 struct strbuf *err); 300 301/* 302 * Add a reference deletion to transaction. If have_old is true, then 303 * old_sha1 holds the value that the reference should have had before 304 * the update (which must not be the null SHA-1). 305 * Function returns 0 on success and non-zero on failure. A failure to delete 306 * means that the transaction as a whole has failed and will need to be 307 * rolled back. 308 */ 309int ref_transaction_delete(struct ref_transaction *transaction, 310 const char *refname, 311 const unsigned char *old_sha1, 312 int flags, int have_old, 313 struct strbuf *err); 314 315/* 316 * Commit all of the changes that have been queued in transaction, as 317 * atomically as possible. Return a nonzero value if there is a 318 * problem. 319 */ 320int ref_transaction_commit(struct ref_transaction *transaction, 321 const char *msg, struct strbuf *err); 322 323/* 324 * Free an existing transaction and all associated data. 325 */ 326void ref_transaction_free(struct ref_transaction *transaction); 327 328/** Lock a ref and then write its file */ 329int update_ref(const char *action, const char *refname, 330 const unsigned char *sha1, const unsigned char *oldval, 331 int flags, enum action_on_err onerr); 332 333extern int parse_hide_refs_config(const char *var, const char *value, const char *); 334extern int ref_is_hidden(const char *); 335 336#endif /* REFS_H */