free column_data once we receive SQLITE_DONE

speedtest.rb

@@ -7,7 +7,7 @@ db.execute("CREATE TABLE t1 (alpha INTEGER)") do |row|
 
 end
 
-count = 100000;
+count = 1000000;
 
 t0 = Time.new;
 1.upto(count) do

sqlite3_bindings.cc

@@ -492,7 +492,7 @@ protected:
       if (stmt_) sqlite3_finalize(stmt_);
       if (column_types_) free(column_types_);
       if (column_names_) free(column_names_);
-      if (column_data_) free(column_data_);
+      if (column_data_) FreeColumnData();
     }
 
     //
@@ -824,13 +824,31 @@ protected:
       }
 
       if (req->result == SQLITE_DONE && sto->column_count_) {
-        free(sto->column_data_);
-        sto->column_data_ = NULL;
+        sto->FreeColumnData();
       }
 
       return 0;
     }
 
+    void FreeColumnData(void) {
+      if (!column_count_) return;
+      for (int i = 0; i < column_count_; i++) {
+        switch (column_types_[i]) {
+          // XXX why does using String::New make v8 croak here?
+          case SQLITE_INTEGER:
+            free(column_data_[i]);
+            break;
+          case SQLITE_FLOAT:
+            free(column_data_[i]);
+            break;
+        }
+        column_data_[i] = NULL;
+      }
+
+      free(column_data_);
+      column_data_ = NULL;
+    }
+
     static int EIO_Step(eio_req *req) {
       Statement *sto = (class Statement *)(req->data);
       sqlite3_stmt *stmt = sto->stmt_;
@@ -875,7 +893,6 @@ protected:
 
             switch(sto->column_types_[i]) {
               case SQLITE_INTEGER:
-                // XXX reuse this space instead of allocating every time
                 sto->column_data_[i] = (int *) malloc(sizeof(int));
                 break;