Fixed problem with types of null values on execute

When a statement containing host variables was executed,
null values could cause the execute to fail depending on the
types of the columns.

Change-Id: I83781f4419411abe4c2e8f39ee52e69ae2032b2c

Author: gperrow-SAP

package.json

@@ -1,8 +1,8 @@
 {
-  "author": "SQL ANYWHERE ",
+  "author": "SQL ANYWHERE",
   "name": "sqlanywhere",
   "description": "SQL Anywhere JavaScript Driver.",
-  "version": "1.0.19",
+  "version": "1.0.20",
   "repository": {
     "url": "https://github.com/sqlanywhere/node-sqlanywhere"
   },

src/sqlanywhere.cpp

@@ -134,7 +134,11 @@ void executeWork( uv_work_t *req )
 	    return;
 	}
 
-	param.value.type = baton->params[i].value.type;
+	if( param.value.type == A_INVALID_TYPE &&
+	    ( baton->params[i].value.is_null == NULL ||
+	      !(*(baton->params[i].value.is_null)) ) ) {
+	    param.value.type = baton->params[i].value.type;
+	}
 	param.value.buffer = baton->params[i].value.buffer;
 	param.value.is_address = baton->params[i].value.is_address;
 

src/sqlanywhere_v0_10.cpp

@@ -126,7 +126,11 @@ void executeWork( uv_work_t *req )
 	    return;
 	}
 
-	param.value.type = baton->params[i].value.type;
+	if( param.value.type == A_INVALID_TYPE &&
+	    ( baton->params[i].value.is_null == NULL ||
+	      !(*(baton->params[i].value.is_null)) ) ) {
+	    param.value.type = baton->params[i].value.type;
+	}
 	param.value.buffer = baton->params[i].value.buffer;
 	param.value.is_address = baton->params[i].value.is_address;