--- BDB/BDB.xs	2008/09/25 13:44:44	1.52
+++ BDB/BDB.xs	2008/09/25 22:09:02	1.53
@@ -353,67 +353,67 @@
 
 static int req_invoke (bdb_req req)
 {
-  dSP;
-
-  if (req->callback)
+  switch (req->type)
     {
-      ENTER;
-      SAVETMPS;
-      PUSHMARK (SP);
-
-      switch (req->type)
-        {
-          case REQ_DB_CLOSE:
-            SvREFCNT_dec (req->sv1);
-            break;
+      case REQ_DB_CLOSE:
+        SvREFCNT_dec (req->sv1);
+        break;
 
-          case REQ_DB_GET:
-          case REQ_DB_PGET:
-            dbt_to_sv (req->sv3, &req->dbt3);
-            break;
+      case REQ_DB_GET:
+      case REQ_DB_PGET:
+        dbt_to_sv (req->sv3, &req->dbt3);
+        break;
 
-          case REQ_C_GET:
-          case REQ_C_PGET:
-            dbt_to_sv (req->sv1, &req->dbt1);
-            dbt_to_sv (req->sv2, &req->dbt2);
-            dbt_to_sv (req->sv3, &req->dbt3);
-            break;
+      case REQ_C_GET:
+      case REQ_C_PGET:
+        dbt_to_sv (req->sv1, &req->dbt1);
+        dbt_to_sv (req->sv2, &req->dbt2);
+        dbt_to_sv (req->sv3, &req->dbt3);
+        break;
 
-          case REQ_DB_PUT:
-          case REQ_C_PUT:
-            dbt_to_sv (0, &req->dbt1);
-            dbt_to_sv (0, &req->dbt2);
-            break;
+      case REQ_DB_PUT:
+      case REQ_C_PUT:
+        dbt_to_sv (0, &req->dbt1);
+        dbt_to_sv (0, &req->dbt2);
+        break;
 
-          case REQ_DB_KEY_RANGE:
-            {
-              AV *av = newAV ();
+      case REQ_DB_KEY_RANGE:
+        {
+          AV *av = newAV ();
 
-              av_push (av, newSVnv (req->key_range.less));
-              av_push (av, newSVnv (req->key_range.equal));
-              av_push (av, newSVnv (req->key_range.greater));
-
-              SvREADONLY_off (req->sv1);
-              sv_setsv_mg (req->sv1, newRV_noinc ((SV *)av));
-              SvREFCNT_dec (req->sv1);
-            }
-            break;
+          av_push (av, newSVnv (req->key_range.less));
+          av_push (av, newSVnv (req->key_range.equal));
+          av_push (av, newSVnv (req->key_range.greater));
+
+          SvREADONLY_off (req->sv1);
+          sv_setsv_mg (req->sv1, newRV_noinc ((SV *)av));
+          SvREFCNT_dec (req->sv1);
+        }
+        break;
 
 #if DB_VERSION_MINOR >= 3
-          case REQ_SEQ_GET:
-            SvREADONLY_off (req->sv1);
+      case REQ_SEQ_GET:
+        SvREADONLY_off (req->sv1);
 
-            if (sizeof (IV) > 4)
-              sv_setiv_mg (req->sv1, (IV)req->seq_t);
-            else
-              sv_setnv_mg (req->sv1, (NV)req->seq_t);
+        if (sizeof (IV) > 4)
+          sv_setiv_mg (req->sv1, (IV)req->seq_t);
+        else
+          sv_setnv_mg (req->sv1, (NV)req->seq_t);
 
-            SvREFCNT_dec (req->sv1);
-            break;
+        SvREFCNT_dec (req->sv1);
+        break;
 #endif
-        }
+    }
+
+  errno = req->result;
 
-      errno = req->result;
+  if (req->callback)
+    {
+      dSP;
+
+      ENTER;
+      SAVETMPS;
+      PUSHMARK (SP);
 
       PUTBACK;
       call_sv (req->callback, G_VOID | G_EVAL);
@@ -421,9 +421,11 @@
 
       FREETMPS;
       LEAVE;
+
+      return !SvTRUE (ERRSV);
     }
 
-  return !SvTRUE (ERRSV);
+  return 1;
 }
 
 static void req_free (bdb_req req)
@@ -487,6 +489,7 @@
   respipe_osf [1] = TO_SOCKET (respipe [1]);
 }
 
+static void bdb_request (bdb_req req);
 X_THREAD_PROC (bdb_proc);
 
 static void start_thread (void)
@@ -543,19 +546,30 @@
   // synthesize callback if none given
   if (!req->callback)
     {
-      int count;
+      if (SvOK (prepare_cb))
+        {
+          int count;
 
-      dSP;
-      PUSHMARK (SP);
-      PUTBACK;
-      count = call_sv (prepare_cb, G_ARRAY);
-      SPAGAIN;
+          dSP;
+          PUSHMARK (SP);
+          PUTBACK;
+          count = call_sv (prepare_cb, G_ARRAY);
+          SPAGAIN;
 
-      if (count != 2)
-        croak ("prepare callback must return exactly two values\n");
+          if (count != 2)
+            croak ("prepare callback must return exactly two values\n");
 
-      wait_callback = POPs;
-      req->callback = SvREFCNT_inc (POPs);
+          wait_callback = POPs;
+          req->callback = SvREFCNT_inc (POPs);
+        }
+      else
+        {
+          // execute request synchronously
+          bdb_request (req);
+          req_invoke (req);
+          req_free (req);
+          return;
+        }
     }
 
   ++nreqs;
@@ -1330,6 +1344,8 @@
         for (civ = const_iv + sizeof (const_iv) / sizeof (const_iv [0]); civ-- > const_iv; )
           newCONSTSUB (stash, (char *)civ->name, newSViv (civ->iv));
 
+        prepare_cb = &PL_sv_undef;
+
         {
           /* we currently only allow version, minor-version and patchlevel to go up to 255 */
           char vstring[3] = { DB_VERSION_MAJOR, DB_VERSION_MINOR, DB_VERSION_PATCH };
@@ -1477,12 +1493,14 @@
 	OUTPUT:
 	RETVAL
 
-void
+SV *
 set_sync_prepare (SV *cb)
 	PROTOTYPE: &
 	CODE:
-        SvREFCNT_dec (prepare_cb);
+        RETVAL = prepare_cb;
         prepare_cb = newSVsv (cb);
+	OUTPUT:
+        RETVAL
 
 char *
 strerror (int errorno = errno)