Gdbm: Update to new iterator API.

Fixes some of #10085.

src/modules/Gdbm/gdbmmod.c

@@ -389,7 +389,7 @@ static void gdbmmod_firstkey(INT32 args)
     push_string(DATUM_TO_STRING(ret));
     free(ret.dptr);
   } else {
-    push_int(0);
+    push_undefined();
   }
 }
 
@@ -448,7 +448,7 @@ static void gdbmmod_nextkey(INT32 args)
     push_string(DATUM_TO_STRING(ret));
     free(ret.dptr);
   } else {
-    push_int(0);
+    push_undefined();
   }
 }
 
@@ -589,33 +589,30 @@ static void gdbmmod_sync(INT32 UNUSED(args))
 static void gdbmmod_iter_first(INT32 UNUSED(args))
 {
   struct gdbm_glue *this=THIS;
-  gdbmmod_firstkey(0);
-  if( Pike_sp[-1].u.string )
-    this->iter = Pike_sp[-1].u.string;
-  Pike_sp--;
-  push_int( !!this->iter );
+  if (this->iter) {
+    free_string(this->iter);
+  }
+  this->iter = NULL;
 }
 
 static void gdbmmod_iter_next(INT32 UNUSED(args))
 {
   struct gdbm_glue *this=THIS;
-  if(!this->iter)
-  {
-      push_undefined();
-      return;
-  }
+
+  if(!this->iter) {
+    gdbmmod_firstkey(0);
+  } else {
     push_string( this->iter );
+    this->iter = NULL;
     gdbmmod_nextkey(1);
-  if( TYPEOF(Pike_sp[-1]) != PIKE_T_STRING )
-  {
-    this->iter = 0;
-    push_undefined();
-    return;
   }
+
+  if( TYPEOF(Pike_sp[-1]) == PIKE_T_STRING ) {
     this->iter = Pike_sp[-1].u.string;
-  push_int(1);
+    add_ref(this->iter);
     return;
-
+  }
+  push_undefined();
 }
 
 static void gdbmmod_iter_index(INT32 UNUSED(args))
@@ -627,11 +624,6 @@ static void gdbmmod_iter_index(INT32 UNUSED(args))
     push_undefined();
 }
 
-static void gdbmmod_iter_no_value(INT32 UNUSED(args))
-{
-  push_int( !THIS->iter );
-}
-
 static void gdbmmod_iter_value(INT32 UNUSED(args))
 {
   struct gdbm_glue *this=THIS;
@@ -695,9 +687,8 @@ static void gdbmmod_values(INT32 UNUSED(args))
 static void gdbmmod_get_iterator(INT32 UNUSED(args))
 {
   push_object( clone_object( iterator, 0 ) );
+  THIS->iter = NULL;
   *((struct gdbm_glue *)Pike_sp[-1].u.object->storage) = *THIS;
-  apply(Pike_sp[-1].u.object, "first", 0);
-  pop_stack();
 }
 
 
@@ -808,8 +799,6 @@ PIKE_MODULE_INIT
 	       ID_PROTECTED);
   ADD_FUNCTION("_iterator_value", gdbmmod_iter_value, tFunc(tNone,tStr8),
 	       ID_PROTECTED);
-  ADD_FUNCTION("`!",    gdbmmod_iter_no_value, tFunc(tNone,tInt01),
-	       ID_PROTECTED);
   set_exit_callback(exit_gdbm_iterator);
   iterator = end_program();
   add_program_constant( "Iterator", iterator, 0 );