X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb2%2Ftdb2.h;h=0731503b874ce130649f1bb64964460b1c7ad9f1;hp=52c234f1c8b77ea7b542c09219e412f99db5b872;hb=6ce40d6ab4dbd63bd76979b8491351708c3df892;hpb=f513c5701b184fd1c0a6f03431c7fdda3ab6d2cf

diff --git a/ccan/tdb2/tdb2.h b/ccan/tdb2/tdb2.h
index 52c234f1..0731503b 100644
--- a/ccan/tdb2/tdb2.h
+++ b/ccan/tdb2/tdb2.h
@@ -311,7 +311,7 @@ enum TDB_ERROR tdb_transaction_prepare_commit(struct tdb_context *tdb);
  * a negative enum TDB_ERROR value.
  */
 #define tdb_traverse(tdb, fn, p)					\
-	tdb_traverse_(tdb, typesafe_cb_preargs(int, (fn), (p),		\
+	tdb_traverse_(tdb, typesafe_cb_preargs(int, void *, (fn), (p),	\
 					       struct tdb_context *,	\
 					       TDB_DATA, TDB_DATA), (p))
 
@@ -324,7 +324,7 @@ int64_t tdb_traverse_(struct tdb_context *tdb,
  * @tdb: the tdb context returned from tdb_open()
  * @key: the key whose record we should hand to @parse
  * @parse: the function to call for the data
- * @p: the private pointer to hand to @parse (types must match).
+ * @data: the private pointer to hand to @parse (types must match).
  *
  * This avoids a copy for many cases, by handing you a pointer into
  * the memory-mapped database.  It also locks the record to prevent
@@ -332,17 +332,18 @@ int64_t tdb_traverse_(struct tdb_context *tdb,
  *
  * Do not alter the data handed to parse()!
  */
-#define tdb_parse_record(tdb, key, parse, p)				\
+#define tdb_parse_record(tdb, key, parse, data)				\
 	tdb_parse_record_((tdb), (key),					\
-			  typesafe_cb_preargs(enum TDB_ERROR, (parse), (p), \
-					      TDB_DATA, TDB_DATA), (p))
+			  typesafe_cb_preargs(enum TDB_ERROR, void *,	\
+					      (parse), (data),		\
+					      TDB_DATA, TDB_DATA), (data))
 
 enum TDB_ERROR tdb_parse_record_(struct tdb_context *tdb,
 				 TDB_DATA key,
-				 enum TDB_ERROR (*parse)(TDB_DATA key,
-							 TDB_DATA data,
-							 void *p),
-				 void *p);
+				 enum TDB_ERROR (*parse)(TDB_DATA k,
+							 TDB_DATA d,
+							 void *data),
+				 void *data);
 
 /**
  * tdb_get_seqnum - get a database sequence number
@@ -394,7 +395,7 @@ enum TDB_ERROR tdb_nextkey(struct tdb_context *tdb, struct tdb_data *key);
  * @tdb: the tdb context returned from tdb_open()
  * @key: the key to lock.
  *
- * This prevents any changes from occurring to a group of keys including @key,
+ * This prevents any access occurring to a group of keys including @key,
  * even if @key does not exist.  This allows primitive atomic updates of
  * records without using transactions.
  *
@@ -416,6 +417,33 @@ enum TDB_ERROR tdb_chainlock(struct tdb_context *tdb, TDB_DATA key);
  */
 void tdb_chainunlock(struct tdb_context *tdb, TDB_DATA key);
 
+/**
+ * tdb_chainlock_read - lock a record in the TDB, for reading
+ * @tdb: the tdb context returned from tdb_open()
+ * @key: the key to lock.
+ *
+ * This prevents any changes from occurring to a group of keys including @key,
+ * even if @key does not exist.  This allows primitive atomic updates of
+ * records without using transactions.
+ *
+ * You cannot begin a transaction while holding a tdb_chainlock_read(), nor can
+ * you do any operations on any other keys in the database.  This also means
+ * that you cannot hold more than one tdb_chainlock()/read() at a time.
+ *
+ * See Also:
+ *	tdb_chainlock()
+ */
+enum TDB_ERROR tdb_chainlock_read(struct tdb_context *tdb, TDB_DATA key);
+
+/**
+ * tdb_chainunlock_read - unlock a record in the TDB for reading
+ * @tdb: the tdb context returned from tdb_open()
+ * @key: the key to unlock.
+ *
+ * The key must have previously been locked by tdb_chainlock_read().
+ */
+void tdb_chainunlock_read(struct tdb_context *tdb, TDB_DATA key);
+
 /**
  * tdb_lockall - lock the entire TDB
  * @tdb: the tdb context returned from tdb_open()
@@ -462,7 +490,7 @@ enum TDB_ERROR tdb_wipe_all(struct tdb_context *tdb);
  * 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: argument for @check, must match type.
+ * @data: 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
@@ -471,18 +499,18 @@ enum TDB_ERROR tdb_wipe_all(struct tdb_context *tdb);
  *
  * Returns TDB_SUCCESS or an error.
  */
-#define tdb_check(tdb, check, private)					\
-	tdb_check_((tdb), typesafe_cb_preargs(enum TDB_ERROR,		\
-					      (check), (private),	\
+#define tdb_check(tdb, check, data)					\
+	tdb_check_((tdb), typesafe_cb_preargs(enum TDB_ERROR, void *,	\
+					      (check), (data),		\
 					      struct tdb_data,		\
 					      struct tdb_data),		\
-		   (private))
+		   (data))
 
 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_ERROR (*check)(struct tdb_data k,
+						  struct tdb_data d,
+						  void *data),
+			  void *data);
 
 /**
  * tdb_error - get the last error (not threadsafe)
@@ -612,11 +640,11 @@ enum tdb_log_level {
  */
 struct tdb_attribute_log {
 	struct tdb_attribute_base base; /* .attr = TDB_ATTRIBUTE_LOG */
-	void (*log_fn)(struct tdb_context *tdb,
-		       enum tdb_log_level level,
-		       void *log_private,
-		       const char *message);
-	void *log_private;
+	void (*fn)(struct tdb_context *tdb,
+		   enum tdb_log_level level,
+		   const char *message,
+		   void *data);
+	void *data;
 };
 
 /**
@@ -633,9 +661,9 @@ struct tdb_attribute_log {
  */
 struct tdb_attribute_hash {
 	struct tdb_attribute_base base; /* .attr = TDB_ATTRIBUTE_HASH */
-	uint64_t (*hash_fn)(const void *key, size_t len, uint64_t seed,
-			    void *priv);
-	void *hash_private;
+	uint64_t (*fn)(const void *key, size_t len, uint64_t seed,
+		       void *data);
+	void *data;
 };
 
 /**