28e7834da46e5a859a69da6452f2b8a2841a0528
   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 ref_transaction_update(), ref_transaction_create(), etc.
 185 * REF_NODEREF: act on the ref directly, instead of dereferencing
 186 *              symbolic references.
 187 * REF_DELETING: tolerate broken refs
 188 *
 189 * Flags >= 0x100 are reserved for internal use.
 190 */
 191#define REF_NODEREF     0x01
 192#define REF_DELETING    0x02
 193
 194/*
 195 * Setup reflog before using. Set errno to something meaningful on failure.
 196 */
 197int log_ref_setup(const char *refname, char *logfile, int bufsize);
 198
 199/** Reads log for the value of ref during at_time. **/
 200extern int read_ref_at(const char *refname, unsigned int flags,
 201                       unsigned long at_time, int cnt,
 202                       unsigned char *sha1, char **msg,
 203                       unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt);
 204
 205/** Check if a particular reflog exists */
 206extern int reflog_exists(const char *refname);
 207
 208/** Delete a reflog */
 209extern int delete_reflog(const char *refname);
 210
 211/* iterate over reflog entries */
 212typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *);
 213int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data);
 214int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data);
 215
 216/*
 217 * Calls the specified function for each reflog file until it returns nonzero,
 218 * and returns the value
 219 */
 220extern int for_each_reflog(each_ref_fn, void *);
 221
 222#define REFNAME_ALLOW_ONELEVEL 1
 223#define REFNAME_REFSPEC_PATTERN 2
 224
 225/*
 226 * Return 0 iff refname has the correct format for a refname according
 227 * to the rules described in Documentation/git-check-ref-format.txt.
 228 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level
 229 * reference names.  If REFNAME_REFSPEC_PATTERN is set in flags, then
 230 * allow a "*" wildcard character in place of one of the name
 231 * components.  No leading or repeated slashes are accepted.
 232 */
 233extern int check_refname_format(const char *refname, int flags);
 234
 235extern const char *prettify_refname(const char *refname);
 236extern char *shorten_unambiguous_ref(const char *refname, int strict);
 237
 238/** rename ref, return 0 on success **/
 239extern int rename_ref(const char *oldref, const char *newref, const char *logmsg);
 240
 241/**
 242 * Resolve refname in the nested "gitlink" repository that is located
 243 * at path.  If the resolution is successful, return 0 and set sha1 to
 244 * the name of the object; otherwise, return a non-zero value.
 245 */
 246extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1);
 247
 248enum action_on_err {
 249        UPDATE_REFS_MSG_ON_ERR,
 250        UPDATE_REFS_DIE_ON_ERR,
 251        UPDATE_REFS_QUIET_ON_ERR
 252};
 253
 254/*
 255 * Begin a reference transaction.  The reference transaction must
 256 * be freed by calling ref_transaction_free().
 257 */
 258struct ref_transaction *ref_transaction_begin(struct strbuf *err);
 259
 260/*
 261 * The following functions add a reference check or update to a
 262 * ref_transaction.  In all of them, refname is the name of the
 263 * reference to be affected.  The functions make internal copies of
 264 * refname and msg, so the caller retains ownership of these parameters.
 265 * flags can be REF_NODEREF; it is passed to update_ref_lock().
 266 */
 267
 268/*
 269 * Add a reference update to transaction.  new_sha1 is the value that
 270 * the reference should have after the update, or null_sha1 if it should
 271 * be deleted.  If have_old is true, then old_sha1 holds the value
 272 * that the reference should have had before the update, or zeros if
 273 * it must not have existed beforehand.
 274 * Function returns 0 on success and non-zero on failure. A failure to update
 275 * means that the transaction as a whole has failed and will need to be
 276 * rolled back.
 277 */
 278int ref_transaction_update(struct ref_transaction *transaction,
 279                           const char *refname,
 280                           const unsigned char *new_sha1,
 281                           const unsigned char *old_sha1,
 282                           int flags, int have_old, const char *msg,
 283                           struct strbuf *err);
 284
 285/*
 286 * Add a reference creation to transaction.  new_sha1 is the value
 287 * that the reference should have after the update; it must not be the
 288 * null SHA-1.  It is verified that the reference does not exist
 289 * already.
 290 * Function returns 0 on success and non-zero on failure. A failure to create
 291 * means that the transaction as a whole has failed and will need to be
 292 * rolled back.
 293 */
 294int ref_transaction_create(struct ref_transaction *transaction,
 295                           const char *refname,
 296                           const unsigned char *new_sha1,
 297                           int flags, const char *msg,
 298                           struct strbuf *err);
 299
 300/*
 301 * Add a reference deletion to transaction.  If have_old is true, then
 302 * old_sha1 holds the value that the reference should have had before
 303 * the update (which must not be the null SHA-1).
 304 * Function returns 0 on success and non-zero on failure. A failure to delete
 305 * means that the transaction as a whole has failed and will need to be
 306 * rolled back.
 307 */
 308int ref_transaction_delete(struct ref_transaction *transaction,
 309                           const char *refname,
 310                           const unsigned char *old_sha1,
 311                           int flags, int have_old, const char *msg,
 312                           struct strbuf *err);
 313
 314/*
 315 * Commit all of the changes that have been queued in transaction, as
 316 * atomically as possible.
 317 *
 318 * Returns 0 for success, or one of the below error codes for errors.
 319 */
 320/* Naming conflict (for example, the ref names A and A/B conflict). */
 321#define TRANSACTION_NAME_CONFLICT -1
 322/* All other errors. */
 323#define TRANSACTION_GENERIC_ERROR -2
 324int ref_transaction_commit(struct ref_transaction *transaction,
 325                           struct strbuf *err);
 326
 327/*
 328 * Free an existing transaction and all associated data.
 329 */
 330void ref_transaction_free(struct ref_transaction *transaction);
 331
 332/** Lock a ref and then write its file */
 333int update_ref(const char *action, const char *refname,
 334                const unsigned char *sha1, const unsigned char *oldval,
 335                int flags, enum action_on_err onerr);
 336
 337extern int parse_hide_refs_config(const char *var, const char *value, const char *);
 338extern int ref_is_hidden(const char *);
 339
 340enum expire_reflog_flags {
 341        EXPIRE_REFLOGS_DRY_RUN = 1 << 0,
 342        EXPIRE_REFLOGS_UPDATE_REF = 1 << 1,
 343        EXPIRE_REFLOGS_VERBOSE = 1 << 2,
 344        EXPIRE_REFLOGS_REWRITE = 1 << 3
 345};
 346
 347/*
 348 * The following interface is used for reflog expiration. The caller
 349 * calls reflog_expire(), supplying it with three callback functions,
 350 * of the following types. The callback functions define the
 351 * expiration policy that is desired.
 352 *
 353 * reflog_expiry_prepare_fn -- Called once after the reference is
 354 *     locked.
 355 *
 356 * reflog_expiry_should_prune_fn -- Called once for each entry in the
 357 *     existing reflog. It should return true iff that entry should be
 358 *     pruned.
 359 *
 360 * reflog_expiry_cleanup_fn -- Called once before the reference is
 361 *     unlocked again.
 362 */
 363typedef void reflog_expiry_prepare_fn(const char *refname,
 364                                      const unsigned char *sha1,
 365                                      void *cb_data);
 366typedef int reflog_expiry_should_prune_fn(unsigned char *osha1,
 367                                          unsigned char *nsha1,
 368                                          const char *email,
 369                                          unsigned long timestamp, int tz,
 370                                          const char *message, void *cb_data);
 371typedef void reflog_expiry_cleanup_fn(void *cb_data);
 372
 373/*
 374 * Expire reflog entries for the specified reference. sha1 is the old
 375 * value of the reference. flags is a combination of the constants in
 376 * enum expire_reflog_flags. The three function pointers are described
 377 * above. On success, return zero.
 378 */
 379extern int reflog_expire(const char *refname, const unsigned char *sha1,
 380                         unsigned int flags,
 381                         reflog_expiry_prepare_fn prepare_fn,
 382                         reflog_expiry_should_prune_fn should_prune_fn,
 383                         reflog_expiry_cleanup_fn cleanup_fn,
 384                         void *policy_cb_data);
 385
 386#endif /* REFS_H */