Don't dereference null pointers, don't go passing them to the parser (stops lots of glib asserts).

1 files changed, 17 insertions, 13 deletions

diff --git a/vxi11_server.c b/vxi11_server.c
index 2d1a455..f367694 100644
--- a/vxi11_server.c
+++ b/vxi11_server.c
@@ -254,16 +254,20 @@ device_write_1_svc(Device_WriteParms *argp, struct svc_req *rqstp) {
 	else {
 		touchlink(argp->lid);
 		links[argp->lid]->aborted = false;
-		gchar* str = g_strndup(argp->data.data_val, argp->data.data_len);
-#ifdef DEBUG
-		int n;
-		for (n = 0; str[n] != '\0'; n++)
-			printf("%02x ", (unsigned char) str[n]);
-		printf("\n");
-		printf("got <<%s>> (reported length %d)on link %d.\n", str, (int) argp->data.data_len, (int) argp->lid);
-#endif
-		Parser_main(str, 0, GPIB_and_VXI_start_query_response, NULL );
-		g_free(str);
+		gchar* str = NULL;
+		if (argp->data.data_val != NULL )
+			str = g_strndup(argp->data.data_val, argp->data.data_len);
+		if (str != NULL ) {
+#ifdef DEBUG
+			int n;
+			for (n = 0; str[n] != '\0'; n++)
+				printf("%02x ", (unsigned char) str[n]);
+			printf("\n");
+			printf("got <<%s>> (reported length %d)on link %d.\n", str, (int) argp->data.data_len, (int) argp->lid);
+#endif
+			Parser_main(str, 0, GPIB_and_VXI_start_query_response, NULL );
+			g_free(str);
+		}
 		result.size = argp->data.data_len;
 	}
 
@@ -277,7 +281,7 @@ device_read_1_svc(Device_ReadParms *argp, struct svc_req *rqstp) {
 	printf("device_read_1_svc()\n");
 #endif
 
-	// this free's the data from the last call
+// this free's the data from the last call
 	if (result.data.data_val != NULL )
 		g_free(result.data.data_val);
 
@@ -549,8 +553,8 @@ create_intr_chan_1_svc(Device_RemoteFunc *argp, struct svc_req *rqstp) {
 	printf("Client %s is asking for an interrupt connection on port %u\n", clientaddressstring, (unsigned int) port);
 #endif
 
-	// if a client had an interrupt channel and died without closing it
-	// we need to clean it up to avoid a deadlock
+// if a client had an interrupt channel and died without closing it
+// we need to clean it up to avoid a deadlock
 	static struct rpc_err err;
 	if (intclient != NULL ) {
 		vxi11_fireinterrupt();