#include <stdint.h>
#endif
#include <ccan/compiler/compiler.h>
+#include <ccan/typesafe_cb/typesafe_cb.h>
union tdb_attribute;
struct tdb_context;
TDB_ERR_EXISTS = -5, /* The key already exists. */
TDB_ERR_NOEXIST = -6, /* The key does not exist. */
TDB_ERR_EINVAL = -7, /* You're using it wrong. */
- TDB_ERR_RDONLY = -8 /* The database is read-only. */
+ TDB_ERR_RDONLY = -8, /* The database is read-only. */
+ TDB_ERR_LAST = TDB_ERR_RDONLY
};
/**
*
* This inserts (or overwrites) a key/value pair in the TDB. If flag
* is TDB_REPLACE, it doesn't matter whether the key exists or not;
- * TDB_INSERT means it must not exist (TDB_ERR_EXISTS otherwise),
- * and TDB_MODIFY means it must exist (TDB_ERR_NOEXIST otherwise).
+ * TDB_INSERT means it must not exist (returns TDB_ERR_EXISTS otherwise),
+ * and TDB_MODIFY means it must exist (returns TDB_ERR_NOEXIST otherwise).
*
- * On success, this returns 0, on failure -1, and sets tdb_error().
+ * On success, this returns TDB_SUCCESS.
*
* See also:
* tdb_fetch, tdb_transaction_start, tdb_append, tdb_delete.
*/
-int tdb_store(struct tdb_context *tdb,
- struct tdb_data key,
- struct tdb_data dbuf,
- int flag);
+enum TDB_ERROR tdb_store(struct tdb_context *tdb,
+ struct tdb_data key,
+ struct tdb_data dbuf,
+ int flag);
/* flags to tdb_store() */
#define TDB_REPLACE 1 /* A readability place holder */
* tdb_fetch - fetch a value from a tdb.
* @tdb: the tdb context returned from tdb_open()
* @key: the key
+ * @data: pointer to data.
*
- * This looks up a key in the database and returns it, or returns tdb_null
- * and sets tdb_error() if there's a problem (usually, TDB_ERR_NOEXIST).
+ * This looks up a key in the database and sets it in @data.
*
- * It is your responsibility to call free() on the returned structure's
- * dptr.
- */
-struct tdb_data tdb_fetch(struct tdb_context *tdb, struct tdb_data key);
-
-/**
- * enum TDB_ERROR - error codes for TDB
+ * If it returns TDB_SUCCESS, the key was found: it is your
+ * responsibility to call free() on @data->dptr.
*
- * See Also:
- * tdb_error(), tdb_errorstr()
+ * Otherwise, it returns an error (usually, TDB_ERR_NOEXIST) and @data is
+ * undefined.
*/
-
-/**
- * tdb_error - fetch the last error value from the tdb.
- * @tdb: the tdb context returned from tdb_open()
- *
- * This returns the last error, or TDB_SUCCESS. It always returns TDB_SUCCESS
- * immediately after tdb_open() returns the (non-NULL) tdb context.
- *
- * See Also:
- * tdb_errorstr()
- */
-enum TDB_ERROR tdb_error(const struct tdb_context *tdb);
+enum TDB_ERROR tdb_fetch(struct tdb_context *tdb, struct tdb_data key,
+ struct tdb_data *data);
/**
* tdb_errorstr - map the tdb error onto a constant readable string
- * @tdb: the tdb context returned from tdb_open()
+ * @ecode: the enum TDB_ERROR to map.
*
- * This is more useful for displaying errors to users than tdb_error.
- *
- * See Also:
- * tdb_error()
+ * This is useful for displaying errors to users.
*/
-const char *tdb_errorstr(const struct tdb_context *tdb);
+const char *tdb_errorstr(enum TDB_ERROR ecode);
/**
* tdb_append - append a value to a key/value pair in a tdb.
* doesn't exist, it's equivalent to tdb_store (with an additional hint that
* you expect to expand the record in future).
*
- * Returns 0 on success, -1 on failure (and sets tdb_error()).
- *
* See Also:
* tdb_fetch(), tdb_store()
*/
-int tdb_append(struct tdb_context *tdb,
- struct tdb_data key,
- struct tdb_data dbuf);
+enum TDB_ERROR tdb_append(struct tdb_context *tdb,
+ struct tdb_data key, struct tdb_data dbuf);
/**
* tdb_delete - delete a key from a tdb.
* @tdb: the tdb context returned from tdb_open()
* @key: the key to delete.
*
- * Returns 0 on success, or -1 on error (usually tdb_error() would be
- * TDB_ERR_NOEXIST in that case).
+ * Returns TDB_SUCCESS on success, or an error (usually TDB_ERR_NOEXIST).
*
* See Also:
* tdb_fetch(), tdb_store()
*/
-int tdb_delete(struct tdb_context *tdb, struct tdb_data key);
+enum TDB_ERROR tdb_delete(struct tdb_context *tdb, struct tdb_data key);
/**
* tdb_transaction_start - start a transaction
* to read the tdb, but not alter it (they will block), nor will they see
* any changes until tdb_transaction_commit() is called.
*
- * On failure, returns -1 and sets tdb_error().
- *
* See Also:
* tdb_transaction_cancel, tdb_transaction_commit.
*/
-int tdb_transaction_start(struct tdb_context *tdb);
+enum TDB_ERROR tdb_transaction_start(struct tdb_context *tdb);
/**
* tdb_transaction_cancel - abandon a transaction
* making it robust against machine crashes, but very slow compared to
* other TDB operations.
*
- * Returns 0 on success, or -1 on failure: this can only be caused by
- * unexpected errors (eg. I/O or memory); this is no point looping on
- * transaction failure.
+ * A failure can only be caused by unexpected errors (eg. I/O or
+ * memory); this is no point looping on transaction failure.
*
* See Also:
* tdb_transaction_prepare_commit()
*/
-int tdb_transaction_commit(struct tdb_context *tdb);
+enum TDB_ERROR tdb_transaction_commit(struct tdb_context *tdb);
/**
* tdb_transaction_prepare_commit - prepare to commit a transaction
* tdb_transaction_commit): if this succeeds then a transaction will only
* fail if the write() or fsync() calls fail.
*
- * Returns 0 on success, or -1 on failure.
- *
* See Also:
* tdb_transaction_commit()
*/
-int tdb_transaction_prepare_commit(struct tdb_context *tdb);
-
-/* FIXME: Make typesafe */
-typedef int (*tdb_traverse_func)(struct tdb_context *, TDB_DATA, TDB_DATA, void *);
+enum TDB_ERROR tdb_transaction_prepare_commit(struct tdb_context *tdb);
/**
* tdb_traverse - traverse a TDB
* current key does not undermine the reliability of the traversal.
*
* On success, returns the number of keys iterated. On error returns
- * -1 and sets tdb_error().
+ * a negative enum TDB_ERROR value.
*/
-int64_t tdb_traverse(struct tdb_context *tdb, tdb_traverse_func fn, void *p);
+#define tdb_traverse(tdb, fn, p) \
+ tdb_traverse_(tdb, typesafe_cb_preargs(int, (fn), (p), \
+ struct tdb_context *, \
+ TDB_DATA, TDB_DATA), (p))
+
+int64_t tdb_traverse_(struct tdb_context *tdb,
+ int (*fn)(struct tdb_context *,
+ TDB_DATA, TDB_DATA, void *), void *p);
/**
* tdb_firstkey - get the "first" key in a TDB
* @tdb: the tdb context returned from tdb_open()
+ * @key: pointer to key.
*
* This returns an arbitrary key in the database; with tdb_nextkey() it allows
- * open-coded traversal of the database.
+ * open-coded traversal of the database, though it is slightly less efficient
+ * than tdb_traverse.
+ *
+ * It is your responsibility to free @key->dptr on success.
*
- * On failure, returns tdb_null and sets tdb_error(). On success, returns
- * a key, or tdb_null and set tdb_error() to TDB_SUCCESS for an empty database.
+ * Returns TDB_ERR_NOEXIST if the database is empty.
*/
-TDB_DATA tdb_firstkey(struct tdb_context *tdb);
+enum TDB_ERROR tdb_firstkey(struct tdb_context *tdb, struct tdb_data *key);
/**
* tdb_nextkey - get the "next" key in a TDB
* @tdb: the tdb context returned from tdb_open()
* @key: a key returned by tdb_firstkey() or tdb_nextkey().
*
- * This returns another key in the database. On failure or the last key
- * it returns tdb_null: tdb_error() will be TDB_SUCCESS if it was the last key.
+ * This returns another key in the database; it will free @key.dptr for
+ * your convenience.
+ *
+ * Returns TDB_ERR_NOEXIST if there are no more keys.
*/
-TDB_DATA tdb_nextkey(struct tdb_context *tdb, TDB_DATA key);
+enum TDB_ERROR tdb_nextkey(struct tdb_context *tdb, struct tdb_data *key);
/**
* tdb_chainlock - lock a record in the TDB
* See Also:
* tdb_chainunlock()
*/
-int tdb_chainlock(struct tdb_context *tdb, TDB_DATA key);
+enum TDB_ERROR tdb_chainlock(struct tdb_context *tdb, TDB_DATA key);
/**
* tdb_chainunlock - unlock a record in the TDB
* @tdb: the tdb context returned from tdb_open()
* @key: the key to unlock.
*/
-int tdb_chainunlock(struct tdb_context *tdb, TDB_DATA key);
+enum TDB_ERROR tdb_chainunlock(struct tdb_context *tdb, TDB_DATA key);
/**
* tdb_check - check a TDB for consistency
* @tdb: the tdb context returned from tdb_open()
* @check: function to check each key/data pair (or NULL)
- * @private_data: pointer for @check
+ * @private: argument for @check, must match type.
*
* This performs a consistency check of the open database, optionally calling
* a check() function on each record so you can do your own data consistency
- * checks as well. If check() returns non-zero, it is considered a failure.
+ * checks as well. If check() returns an error, that is returned from
+ * tdb_check().
*
- * Returns 0 on success, or -1 on failure and sets tdb_error().
+ * Returns TDB_SUCCESS or an error.
*/
-int tdb_check(struct tdb_context *tdb,
- int (*check)(TDB_DATA key, TDB_DATA data, void *private_data),
- void *private_data);
+#define tdb_check(tdb, check, private) \
+ tdb_check_((tdb), typesafe_cb_preargs(enum TDB_ERROR, \
+ (check), (private), \
+ struct tdb_data, \
+ struct tdb_data), \
+ (private))
+
+enum TDB_ERROR tdb_check_(struct tdb_context *tdb,
+ enum TDB_ERROR (*check)(struct tdb_data key,
+ struct tdb_data data,
+ void *private),
+ void *private);
/**
* enum tdb_summary_flags - flags for tdb_summary.
* tdb_summary - return a string describing the TDB state
* @tdb: the tdb context returned from tdb_open()
* @flags: flags to control the summary output.
+ * @summary: pointer to string to allocate.
*
* This returns a developer-readable string describing the overall
* state of the tdb, such as the percentage used and sizes of records.
* It is designed to provide information about the tdb at a glance
* without displaying any keys or data in the database.
*
- * On success, returns a nul-terminated multi-line string. On failure,
- * returns NULL and sets tdb_error().
+ * On success, sets @summary to point to a malloc()'ed nul-terminated
+ * multi-line string. It is your responsibility to free() it.
*/
-char *tdb_summary(struct tdb_context *tdb, enum tdb_summary_flags flags);
-
-
+enum TDB_ERROR tdb_summary(struct tdb_context *tdb,
+ enum tdb_summary_flags flags,
+ char **summary);
/**
* enum tdb_attribute_type - descriminator for union tdb_attribute.
projects / ccan / blobdiff