X-Git-Url: http://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Ftdb2%2Ftdb2.h;h=84228bdcb95eb66292e30cb40e5ba9713cc099a6;hb=94c8763345a51fe59e97daf4e29051f56331c63c;hp=0940be1ceac40797435eaaa6241cbdd0e787484f;hpb=8d8de08d9079f503256e1682dfa93bb22dcd4ad0;p=ccan

diff --git a/ccan/tdb2/tdb2.h b/ccan/tdb2/tdb2.h
index 0940be1c..84228bdc 100644
--- a/ccan/tdb2/tdb2.h
+++ b/ccan/tdb2/tdb2.h
@@ -45,6 +45,7 @@ extern "C" {
 #endif
 #include <ccan/compiler/compiler.h>
 #include <ccan/typesafe_cb/typesafe_cb.h>
+#include <ccan/cast/cast.h>
 
 union tdb_attribute;
 struct tdb_context;
@@ -221,6 +222,24 @@ static inline bool tdb_deq(struct tdb_data a, struct tdb_data b)
 	return a.dsize == b.dsize && memcmp(a.dptr, b.dptr, a.dsize) == 0;
 }
 
+/**
+ * tdb_mkdata - make a struct tdb_data from const data
+ * @p: the constant pointer
+ * @len: the length
+ *
+ * As the dptr member of struct tdb_data is not constant, you need to
+ * cast it.  This function keeps thost casts in one place, as well as
+ * suppressing the warning some compilers give when casting away a
+ * qualifier (eg. gcc with -Wcast-qual)
+ */
+static inline struct tdb_data tdb_mkdata(const void *p, size_t len)
+{
+	struct tdb_data d;
+	d.dptr = cast_const(void *, p);
+	d.dsize = len;
+	return d;
+}
+
 /**
  * tdb_transaction_start - start a transaction
  * @tdb: the tdb context returned from tdb_open()
@@ -392,8 +411,43 @@ 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.
+ *
+ * The key must have previously been locked by tdb_chainlock().
+ */
+void tdb_chainunlock(struct tdb_context *tdb, TDB_DATA key);
+
+/**
+ * tdb_lockall - lock the entire TDB
+ * @tdb: the tdb context returned from tdb_open()
+ *
+ * You cannot hold a tdb_chainlock while calling this.  It nests, so you
+ * must call tdb_unlockall as many times as you call tdb_lockall.
+ */
+enum TDB_ERROR tdb_lockall(struct tdb_context *tdb);
+
+/**
+ * tdb_unlockall - unlock the entire TDB
+ * @tdb: the tdb context returned from tdb_open()
  */
-enum TDB_ERROR tdb_chainunlock(struct tdb_context *tdb, TDB_DATA key);
+void tdb_unlockall(struct tdb_context *tdb);
+
+/**
+ * tdb_lockall_read - lock the entire TDB for reading
+ * @tdb: the tdb context returned from tdb_open()
+ *
+ * This prevents others writing to the database, eg. tdb_delete, tdb_store,
+ * tdb_append, but not tdb_fetch.
+ *
+ * You cannot hold a tdb_chainlock while calling this.  It nests, so you
+ * must call tdb_unlockall_read as many times as you call tdb_lockall_read.
+ */
+enum TDB_ERROR tdb_lockall_read(struct tdb_context *tdb);
+
+/**
+ * tdb_unlockall_read - unlock the entire TDB for reading
+ * @tdb: the tdb context returned from tdb_open()
+ */
+void tdb_unlockall_read(struct tdb_context *tdb);
 
 /**
  * tdb_wipe_all - wipe the database clean
@@ -408,7 +462,7 @@ 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.
+ * @private_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
@@ -417,18 +471,29 @@ enum TDB_ERROR tdb_wipe_all(struct tdb_context *tdb);
  *
  * Returns TDB_SUCCESS or an error.
  */
-#define tdb_check(tdb, check, private)					\
+#define tdb_check(tdb, check, private_data)				\
 	tdb_check_((tdb), typesafe_cb_preargs(enum TDB_ERROR,		\
-					      (check), (private),	\
+					      (check), (private_data),	\
 					      struct tdb_data,		\
 					      struct tdb_data),		\
-		   (private))
+		   (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);
+						  void *private_data),
+			  void *private_data);
+
+/**
+ * tdb_error - get the last error (not threadsafe)
+ * @tdb: the tdb context returned from tdb_open()
+ *
+ * Returns the last error returned by a TDB function.
+ *
+ * This makes porting from TDB1 easier, but note that the last error is not
+ * reliable in threaded programs.
+ */
+enum TDB_ERROR tdb_error(struct tdb_context *tdb);
 
 /**
  * enum tdb_summary_flags - flags for tdb_summary.