refs.hon commit lock_file(): exit early if lockfile cannot be opened (e31e949)
   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
 163extern int is_branch(const char *refname);
 164
 165/*
 166 * If refname is a non-symbolic reference that refers to a tag object,
 167 * and the tag can be (recursively) dereferenced to a non-tag object,
 168 * store the SHA1 of the referred-to object to sha1 and return 0.  If
 169 * any of these conditions are not met, return a non-zero value.
 170 * Symbolic references are considered unpeelable, even if they
 171 * ultimately resolve to a peelable tag.
 172 */
 173extern int peel_ref(const char *refname, unsigned char *sha1);
 174
 175/*
 176 * Flags controlling lock_any_ref_for_update(), ref_transaction_update(),
 177 * ref_transaction_create(), etc.
 178 * REF_NODEREF: act on the ref directly, instead of dereferencing
 179 *              symbolic references.
 180 *
 181 * Flags >= 0x100 are reserved for internal use.
 182 */
 183#define REF_NODEREF     0x01
 184/*
 185 * This function sets errno to something meaningful on failure.
 186 */
 187extern struct ref_lock *lock_any_ref_for_update(const char *refname,
 188                                                const unsigned char *old_sha1,
 189                                                int flags, int *type_p);
 190
 191/** Close the file descriptor owned by a lock and return the status */
 192extern int close_ref(struct ref_lock *lock);
 193
 194/** Close and commit the ref locked by the lock */
 195extern int commit_ref(struct ref_lock *lock);
 196
 197/** Release any lock taken but not written. **/
 198extern void unlock_ref(struct ref_lock *lock);
 199
 200/** Writes sha1 into the ref specified by the lock. **/
 201extern int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1, const char *msg);
 202
 203/*
 204 * Setup reflog before using. Set errno to something meaningful on failure.
 205 */
 206int log_ref_setup(const char *refname, char *logfile, int bufsize);
 207
 208/** Reads log for the value of ref during at_time. **/
 209extern int read_ref_at(const char *refname, unsigned int flags,
 210                       unsigned long at_time, int cnt,
 211                       unsigned char *sha1, char **msg,
 212                       unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt);
 213
 214/** Check if a particular reflog exists */
 215extern int reflog_exists(const char *refname);
 216
 217/** Delete a reflog */
 218extern int delete_reflog(const char *refname);
 219
 220/* iterate over reflog entries */
 221typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *);
 222int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data);
 223int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data);
 224
 225/*
 226 * Calls the specified function for each reflog file until it returns nonzero,
 227 * and returns the value
 228 */
 229extern int for_each_reflog(each_ref_fn, void *);
 230
 231#define REFNAME_ALLOW_ONELEVEL 1
 232#define REFNAME_REFSPEC_PATTERN 2
 233#define REFNAME_DOT_COMPONENT 4
 234
 235/*
 236 * Return 0 iff refname has the correct format for a refname according
 237 * to the rules described in Documentation/git-check-ref-format.txt.
 238 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level
 239 * reference names.  If REFNAME_REFSPEC_PATTERN is set in flags, then
 240 * allow a "*" wildcard character in place of one of the name
 241 * components.  No leading or repeated slashes are accepted.  If
 242 * REFNAME_DOT_COMPONENT is set in flags, then allow refname
 243 * components to start with "." (but not a whole component equal to
 244 * "." or "..").
 245 */
 246extern int check_refname_format(const char *refname, int flags);
 247
 248extern const char *prettify_refname(const char *refname);
 249extern char *shorten_unambiguous_ref(const char *refname, int strict);
 250
 251/** rename ref, return 0 on success **/
 252extern int rename_ref(const char *oldref, const char *newref, const char *logmsg);
 253
 254/**
 255 * Resolve refname in the nested "gitlink" repository that is located
 256 * at path.  If the resolution is successful, return 0 and set sha1 to
 257 * the name of the object; otherwise, return a non-zero value.
 258 */
 259extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1);
 260
 261enum action_on_err {
 262        UPDATE_REFS_MSG_ON_ERR,
 263        UPDATE_REFS_DIE_ON_ERR,
 264        UPDATE_REFS_QUIET_ON_ERR
 265};
 266
 267/*
 268 * Begin a reference transaction.  The reference transaction must
 269 * be freed by calling ref_transaction_free().
 270 */
 271struct ref_transaction *ref_transaction_begin(struct strbuf *err);
 272
 273/*
 274 * The following functions add a reference check or update to a
 275 * ref_transaction.  In all of them, refname is the name of the
 276 * reference to be affected.  The functions make internal copies of
 277 * refname, so the caller retains ownership of the parameter.  flags
 278 * can be REF_NODEREF; it is passed to update_ref_lock().
 279 */
 280
 281/*
 282 * Add a reference update to transaction.  new_sha1 is the value that
 283 * the reference should have after the update, or zeros if it should
 284 * be deleted.  If have_old is true, then old_sha1 holds the value
 285 * that the reference should have had before the update, or zeros if
 286 * it must not have existed beforehand.
 287 * Function returns 0 on success and non-zero on failure. A failure to update
 288 * means that the transaction as a whole has failed and will need to be
 289 * rolled back.
 290 */
 291int ref_transaction_update(struct ref_transaction *transaction,
 292                           const char *refname,
 293                           const unsigned char *new_sha1,
 294                           const unsigned char *old_sha1,
 295                           int flags, int have_old,
 296                           struct strbuf *err);
 297
 298/*
 299 * Add a reference creation to transaction.  new_sha1 is the value
 300 * that the reference should have after the update; it must not be the
 301 * null SHA-1.  It is verified that the reference does not exist
 302 * already.
 303 * Function returns 0 on success and non-zero on failure. A failure to create
 304 * means that the transaction as a whole has failed and will need to be
 305 * rolled back.
 306 */
 307int ref_transaction_create(struct ref_transaction *transaction,
 308                           const char *refname,
 309                           const unsigned char *new_sha1,
 310                           int flags,
 311                           struct strbuf *err);
 312
 313/*
 314 * Add a reference deletion to transaction.  If have_old is true, then
 315 * old_sha1 holds the value that the reference should have had before
 316 * the update (which must not be the null SHA-1).
 317 * Function returns 0 on success and non-zero on failure. A failure to delete
 318 * means that the transaction as a whole has failed and will need to be
 319 * rolled back.
 320 */
 321int ref_transaction_delete(struct ref_transaction *transaction,
 322                           const char *refname,
 323                           const unsigned char *old_sha1,
 324                           int flags, int have_old,
 325                           struct strbuf *err);
 326
 327/*
 328 * Commit all of the changes that have been queued in transaction, as
 329 * atomically as possible.  Return a nonzero value if there is a
 330 * problem.
 331 */
 332int ref_transaction_commit(struct ref_transaction *transaction,
 333                           const char *msg, struct strbuf *err);
 334
 335/*
 336 * Free an existing transaction and all associated data.
 337 */
 338void ref_transaction_free(struct ref_transaction *transaction);
 339
 340/** Lock a ref and then write its file */
 341int update_ref(const char *action, const char *refname,
 342                const unsigned char *sha1, const unsigned char *oldval,
 343                int flags, enum action_on_err onerr);
 344
 345extern int parse_hide_refs_config(const char *var, const char *value, const char *);
 346extern int ref_is_hidden(const char *);
 347
 348#endif /* REFS_H */