add prototypes for traversal api

cdb.h

@@ -29,7 +29,14 @@ extern void cdb_findstart(struct cdb *);
 extern int cdb_findnext(struct cdb *,const unsigned char *,unsigned long int);
 extern int cdb_find(struct cdb *,const unsigned char *,unsigned long int);
 
+extern int cdb_firstkey(struct cdb *c,uint32 *kpos);
+extern int cdb_nextkey(struct cdb *c,uint32 *kpos);
+
+extern int cdb_successor(struct cdb *c,const unsigned char *,unsigned long int);
+
 #define cdb_datapos(c) ((c)->dpos)
 #define cdb_datalen(c) ((c)->dlen)
+#define cdb_keypos(c) ((c)->kpos)
+#define cdb_keylen(c) ((c)->dpos-(c)->kpos)
 
 #endif

cdb/cdb_traverse.c

@@ -27,7 +27,7 @@ int cdb_nextkey(struct cdb *c,uint32 *kpos) {
   return doit(c,kpos);
 }
 
-int cdb_successor(struct cdb *c,unsigned char *key,unsigned long int klen) {
+int cdb_successor(struct cdb *c,const unsigned char *key,unsigned long int klen) {
   int r;
   uint32 kpos;
   if (key) {