X-Git-Url: http://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Ftdb2%2Ftdb2.h;h=3fa99b15dbb6cab3d09162b3789efd5b8501e875;hb=2f780d578cf2c102957f7872f6edbcbffb8cba69;hp=c91ca7cad08613d53e1bfa3f317f6197eea3db30;hpb=49475d68deecd0b31597ed6094229171d2699b11;p=ccan

diff --git a/ccan/tdb2/tdb2.h b/ccan/tdb2/tdb2.h
index c91ca7ca..3fa99b15 100644
--- a/ccan/tdb2/tdb2.h
+++ b/ccan/tdb2/tdb2.h
@@ -87,6 +87,19 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 #define TDB_ALLOW_NESTING   256 /* fake nested transactions */
 #define TDB_RDONLY   512 /* implied by O_RDONLY */
 #define TDB_VERSION1  1024 /* create/open an old style TDB */
+#define TDB_CANT_CHECK  2048 /* has a feature which we don't understand */
+
+/**
+ * tdb1_incompatible_hash - better (Jenkins) hash for tdb1
+ *
+ * This is better than the default hash for tdb1; but older versions of the
+ * tdb library (prior to version 1.2.6) won't be able to open them.
+ *
+ * It only makes sense to specify this (using tdb_attribute_hash) when
+ * creating (with O_CREAT) an old tdb version using TDB_VERSION1.  It's
+ * equivalent to the TDB_INCOMPATIBLE_HASH flag for tdb1.
+ */
+uint64_t tdb1_incompatible_hash(const void *, size_t, uint64_t, void *);
 
 /**
  * tdb_close - close and free a tdb.
@@ -505,6 +518,16 @@ void tdb_unlockall_read(struct tdb_context *tdb);
  */
 enum TDB_ERROR tdb_wipe_all(struct tdb_context *tdb);
 
+/**
+ * tdb_repack - repack the database
+ * @tdb: the tdb context returned from tdb_open()
+ *
+ * This repacks the database; if it is suffering from a great deal of
+ * fragmentation this might help.  However, it can take twice the
+ * memory of the existing TDB.
+ */
+enum TDB_ERROR tdb_repack(struct tdb_context *tdb);
+
 /**
  * tdb_check - check a TDB for consistency
  * @tdb: the tdb context returned from tdb_open()
@@ -516,6 +539,11 @@ enum TDB_ERROR tdb_wipe_all(struct tdb_context *tdb);
  * checks as well.  If check() returns an error, that is returned from
  * tdb_check().
  *
+ * Note that the TDB uses a feature which we don't understand which
+ * indicates we can't run tdb_check(), this will log a warning to that
+ * effect and return TDB_SUCCESS.  You can detect this condition by
+ * looking for TDB_CANT_CHECK in tdb_get_flags().
+ *
  * Returns TDB_SUCCESS or an error.
  */
 #define tdb_check(tdb, check, data)					\
@@ -609,6 +637,7 @@ enum tdb_attribute_type {
 	TDB_ATTRIBUTE_OPENHOOK = 4,
 	TDB_ATTRIBUTE_FLOCK = 5,
 	TDB_ATTRIBUTE_TDB1_HASHSIZE = 128,
+	TDB_ATTRIBUTE_TDB1_MAX_DEAD = 129,
 };
 
 /**
@@ -853,6 +882,19 @@ struct tdb_attribute_tdb1_hashsize {
 	unsigned int hsize;
 };
 
+/**
+ * struct tdb_attribute_tdb1_max_dead - tdb1 number of maximum dead records.
+ *
+ * TDB1 has a method to speed up its slow free list: it lets a certain
+ * number of "dead" records build up before freeing them.  This is
+ * particularly useful for volatile TDBs; setting it to 5 is
+ * equivalent to tdb1's TDB_VOLATILE flag.
+ */
+struct tdb_attribute_tdb1_max_dead {
+	struct tdb_attribute_base base; /* .attr = TDB_ATTRIBUTE_TDB1_MAX_DEAD */
+	unsigned int max_dead;
+};
+
 /**
  * union tdb_attribute - tdb attributes.
  *
@@ -872,6 +914,7 @@ union tdb_attribute {
 	struct tdb_attribute_openhook openhook;
 	struct tdb_attribute_flock flock;
 	struct tdb_attribute_tdb1_hashsize tdb1_hashsize;
+	struct tdb_attribute_tdb1_max_dead tdb1_max_dead;
 };
 
 #ifdef  __cplusplus