Andrew's git / gitweb.git / refs.h
?
refs.hon commit refs: add a concept of a reference transaction (caa4046)
   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 * Information needed for a single ref update.  Set new_sha1 to the
  15 * new value or to zero to delete the ref.  To check the old value
  16 * while locking the ref, set have_old to 1 and set old_sha1 to the
  17 * value or to zero to ensure the ref does not exist before update.
  18 */
  19struct ref_update {
  20        const char *ref_name;
  21        unsigned char new_sha1[20];
  22        unsigned char old_sha1[20];
  23        int flags; /* REF_NODEREF? */
  24        int have_old; /* 1 if old_sha1 is valid, 0 otherwise */
  25};
  26
  27struct ref_transaction;
  28
  29/*
  30 * Bit values set in the flags argument passed to each_ref_fn():
  31 */
  32
  33/* Reference is a symbolic reference. */
  34#define REF_ISSYMREF 0x01
  35
  36/* Reference is a packed reference. */
  37#define REF_ISPACKED 0x02
  38
  39/*
  40 * Reference cannot be resolved to an object name: dangling symbolic
  41 * reference (directly or indirectly), corrupt reference file, or
  42 * symbolic reference refers to ill-formatted reference name.
  43 */
  44#define REF_ISBROKEN 0x04
  45
  46/*
  47 * The signature for the callback function for the for_each_*()
  48 * functions below.  The memory pointed to by the refname and sha1
  49 * arguments is only guaranteed to be valid for the duration of a
  50 * single callback invocation.
  51 */
  52typedef int each_ref_fn(const char *refname,
  53                        const unsigned char *sha1, int flags, void *cb_data);
  54
  55/*
  56 * The following functions invoke the specified callback function for
  57 * each reference indicated.  If the function ever returns a nonzero
  58 * value, stop the iteration and return that value.  Please note that
  59 * it is not safe to modify references while an iteration is in
  60 * progress, unless the same callback function invocation that
  61 * modifies the reference also returns a nonzero value to immediately
  62 * stop the iteration.
  63 */
  64extern int head_ref(each_ref_fn, void *);
  65extern int for_each_ref(each_ref_fn, void *);
  66extern int for_each_ref_in(const char *, each_ref_fn, void *);
  67extern int for_each_tag_ref(each_ref_fn, void *);
  68extern int for_each_branch_ref(each_ref_fn, void *);
  69extern int for_each_remote_ref(each_ref_fn, void *);
  70extern int for_each_replace_ref(each_ref_fn, void *);
  71extern int for_each_glob_ref(each_ref_fn, const char *pattern, void *);
  72extern int for_each_glob_ref_in(each_ref_fn, const char *pattern, const char* prefix, void *);
  73
  74extern int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
  75extern int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
  76extern int for_each_ref_in_submodule(const char *submodule, const char *prefix,
  77                each_ref_fn fn, void *cb_data);
  78extern int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
  79extern int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
  80extern int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
  81
  82extern int head_ref_namespaced(each_ref_fn fn, void *cb_data);
  83extern int for_each_namespaced_ref(each_ref_fn fn, void *cb_data);
  84
  85static inline const char *has_glob_specials(const char *pattern)
  86{
  87        return strpbrk(pattern, "?*[");
  88}
  89
  90/* can be used to learn about broken ref and symref */
  91extern int for_each_rawref(each_ref_fn, void *);
  92
  93extern void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname);
  94
  95/*
  96 * Lock the packed-refs file for writing.  Flags is passed to
  97 * hold_lock_file_for_update().  Return 0 on success.
  98 */
  99extern int lock_packed_refs(int flags);
 100
 101/*
 102 * Add a reference to the in-memory packed reference cache.  This may
 103 * only be called while the packed-refs file is locked (see
 104 * lock_packed_refs()).  To actually write the packed-refs file, call
 105 * commit_packed_refs().
 106 */
 107extern void add_packed_ref(const char *refname, const unsigned char *sha1);
 108
 109/*
 110 * Write the current version of the packed refs cache from memory to
 111 * disk.  The packed-refs file must already be locked for writing (see
 112 * lock_packed_refs()).  Return zero on success.
 113 */
 114extern int commit_packed_refs(void);
 115
 116/*
 117 * Rollback the lockfile for the packed-refs file, and discard the
 118 * in-memory packed reference cache.  (The packed-refs file will be
 119 * read anew if it is needed again after this function is called.)
 120 */
 121extern void rollback_packed_refs(void);
 122
 123/*
 124 * Flags for controlling behaviour of pack_refs()
 125 * PACK_REFS_PRUNE: Prune loose refs after packing
 126 * PACK_REFS_ALL:   Pack _all_ refs, not just tags and already packed refs
 127 */
 128#define PACK_REFS_PRUNE 0x0001
 129#define PACK_REFS_ALL   0x0002
 130
 131/*
 132 * Write a packed-refs file for the current repository.
 133 * flags: Combination of the above PACK_REFS_* flags.
 134 */
 135int pack_refs(unsigned int flags);
 136
 137extern int ref_exists(const char *);
 138
 139/*
 140 * If refname is a non-symbolic reference that refers to a tag object,
 141 * and the tag can be (recursively) dereferenced to a non-tag object,
 142 * store the SHA1 of the referred-to object to sha1 and return 0.  If
 143 * any of these conditions are not met, return a non-zero value.
 144 * Symbolic references are considered unpeelable, even if they
 145 * ultimately resolve to a peelable tag.
 146 */
 147extern int peel_ref(const char *refname, unsigned char *sha1);
 148
 149/** Locks a "refs/" ref returning the lock on success and NULL on failure. **/
 150extern struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1);
 151
 152/** Locks any ref (for 'HEAD' type refs). */
 153#define REF_NODEREF     0x01
 154extern struct ref_lock *lock_any_ref_for_update(const char *refname,
 155                                                const unsigned char *old_sha1,
 156                                                int flags, int *type_p);
 157
 158/** Close the file descriptor owned by a lock and return the status */
 159extern int close_ref(struct ref_lock *lock);
 160
 161/** Close and commit the ref locked by the lock */
 162extern int commit_ref(struct ref_lock *lock);
 163
 164/** Release any lock taken but not written. **/
 165extern void unlock_ref(struct ref_lock *lock);
 166
 167/** Writes sha1 into the ref specified by the lock. **/
 168extern int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1, const char *msg);
 169
 170/** Setup reflog before using. **/
 171int log_ref_setup(const char *ref_name, char *logfile, int bufsize);
 172
 173/** Reads log for the value of ref during at_time. **/
 174extern int read_ref_at(const char *refname, unsigned long at_time, int cnt,
 175                       unsigned char *sha1, char **msg,
 176                       unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt);
 177
 178/* iterate over reflog entries */
 179typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *);
 180int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data);
 181int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data);
 182
 183/*
 184 * Calls the specified function for each reflog file until it returns nonzero,
 185 * and returns the value
 186 */
 187extern int for_each_reflog(each_ref_fn, void *);
 188
 189#define REFNAME_ALLOW_ONELEVEL 1
 190#define REFNAME_REFSPEC_PATTERN 2
 191#define REFNAME_DOT_COMPONENT 4
 192
 193/*
 194 * Return 0 iff refname has the correct format for a refname according
 195 * to the rules described in Documentation/git-check-ref-format.txt.
 196 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level
 197 * reference names.  If REFNAME_REFSPEC_PATTERN is set in flags, then
 198 * allow a "*" wildcard character in place of one of the name
 199 * components.  No leading or repeated slashes are accepted.  If
 200 * REFNAME_DOT_COMPONENT is set in flags, then allow refname
 201 * components to start with "." (but not a whole component equal to
 202 * "." or "..").
 203 */
 204extern int check_refname_format(const char *refname, int flags);
 205
 206extern const char *prettify_refname(const char *refname);
 207extern char *shorten_unambiguous_ref(const char *refname, int strict);
 208
 209/** rename ref, return 0 on success **/
 210extern int rename_ref(const char *oldref, const char *newref, const char *logmsg);
 211
 212/**
 213 * Resolve refname in the nested "gitlink" repository that is located
 214 * at path.  If the resolution is successful, return 0 and set sha1 to
 215 * the name of the object; otherwise, return a non-zero value.
 216 */
 217extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1);
 218
 219enum action_on_err {
 220        UPDATE_REFS_MSG_ON_ERR,
 221        UPDATE_REFS_DIE_ON_ERR,
 222        UPDATE_REFS_QUIET_ON_ERR
 223};
 224
 225/*
 226 * Begin a reference transaction.  The reference transaction must
 227 * eventually be commited using ref_transaction_commit() or rolled
 228 * back using ref_transaction_rollback().
 229 */
 230struct ref_transaction *ref_transaction_begin(void);
 231
 232/*
 233 * Roll back a ref_transaction and free all associated data.
 234 */
 235void ref_transaction_rollback(struct ref_transaction *transaction);
 236
 237
 238/*
 239 * The following functions add a reference check or update to a
 240 * ref_transaction.  In all of them, refname is the name of the
 241 * reference to be affected.  The functions make internal copies of
 242 * refname, so the caller retains ownership of the parameter.  flags
 243 * can be REF_NODEREF; it is passed to update_ref_lock().
 244 */
 245
 246
 247/*
 248 * Add a reference update to transaction.  new_sha1 is the value that
 249 * the reference should have after the update, or zeros if it should
 250 * be deleted.  If have_old is true, then old_sha1 holds the value
 251 * that the reference should have had before the update, or zeros if
 252 * it must not have existed beforehand.
 253 */
 254void ref_transaction_update(struct ref_transaction *transaction,
 255                            const char *refname,
 256                            unsigned char *new_sha1, unsigned char *old_sha1,
 257                            int flags, int have_old);
 258
 259/*
 260 * Add a reference creation to transaction.  new_sha1 is the value
 261 * that the reference should have after the update; it must not be the
 262 * null SHA-1.  It is verified that the reference does not exist
 263 * already.
 264 */
 265void ref_transaction_create(struct ref_transaction *transaction,
 266                            const char *refname,
 267                            unsigned char *new_sha1,
 268                            int flags);
 269
 270/*
 271 * Add a reference deletion to transaction.  If have_old is true, then
 272 * old_sha1 holds the value that the reference should have had before
 273 * the update (which must not be the null SHA-1).
 274 */
 275void ref_transaction_delete(struct ref_transaction *transaction,
 276                            const char *refname,
 277                            unsigned char *old_sha1,
 278                            int flags, int have_old);
 279
 280/*
 281 * Commit all of the changes that have been queued in transaction, as
 282 * atomically as possible.  Return a nonzero value if there is a
 283 * problem.  The ref_transaction is freed by this function.
 284 */
 285int ref_transaction_commit(struct ref_transaction *transaction,
 286                           const char *msg, enum action_on_err onerr);
 287
 288/** Lock a ref and then write its file */
 289int update_ref(const char *action, const char *refname,
 290                const unsigned char *sha1, const unsigned char *oldval,
 291                int flags, enum action_on_err onerr);
 292
 293/**
 294 * Lock all refs and then perform all modifications.
 295 */
 296int update_refs(const char *action, struct ref_update * const *updates,
 297                int n, enum action_on_err onerr);
 298
 299extern int parse_hide_refs_config(const char *var, const char *value, const char *);
 300extern int ref_is_hidden(const char *);
 301
 302#endif /* REFS_H */