tdb2: shrink free header from 32 to 24 bytes.

[ccan] / ccan / tdb2 / private.h

diff --git a/ccan/tdb2/private.h b/ccan/tdb2/private.h
index 387e49f61182af8fe33028840ebc3be073fea70a..a10d1070d29c3d5f84f09107d032fbb0cf0dac1b 100644 (file)
--- a/ccan/tdb2/private.h
+++ b/ccan/tdb2/private.h
@@ -173,20 +173,30 @@ static inline uint16_t rec_magic(const struct tdb_used_record *r)
 }
 
 struct tdb_free_record {
-        uint64_t magic_and_meta; /* TDB_OFF_UPPER_STEAL bits of magic */
-        uint64_t data_len; /* Not counting these two fields. */
-       /* This is why the minimum record size is 16 bytes.  */
-       uint64_t next, prev;
+        uint64_t magic_and_prev; /* TDB_OFF_UPPER_STEAL bits magic, then prev */
+        uint64_t flist_and_len; /* Len not counting these two fields. */
+       /* This is why the minimum record size is 8 bytes.  */
+       uint64_t next;
 };
 
+static inline uint64_t frec_prev(const struct tdb_free_record *f)
+{
+       return f->magic_and_prev & ((1ULL << (64 - TDB_OFF_UPPER_STEAL)) - 1);
+}
+
 static inline uint64_t frec_magic(const struct tdb_free_record *f)
 {
-       return f->magic_and_meta >> (64 - TDB_OFF_UPPER_STEAL);
+       return f->magic_and_prev >> (64 - TDB_OFF_UPPER_STEAL);
+}
+
+static inline uint64_t frec_len(const struct tdb_free_record *f)
+{
+       return f->flist_and_len & ((1ULL << (64 - TDB_OFF_UPPER_STEAL))-1);
 }
 
-static inline uint64_t frec_flist(const struct tdb_free_record *f)
+static inline unsigned frec_flist(const struct tdb_free_record *f)
 {
-       return f->magic_and_meta & ((1ULL << (64 - TDB_OFF_UPPER_STEAL)) - 1);
+       return f->flist_and_len >> (64 - TDB_OFF_UPPER_STEAL);
 }
 
 struct tdb_recovery_record {
@@ -311,6 +321,7 @@ struct tdb_context {
        
        /* What freelist are we using? */
        uint64_t flist_off;
+       unsigned int flist;
 
        /* IO methods: changes for transactions. */
        const struct tdb_methods *methods;