Brad Powell
The xplane_io (X-Plane I/O) program is used to establish network communications, via UDP, with the X-Plane flight simulator running on a computer. The code consists of class libraries that abstract the lower-level UDP packet encoding and decoding details, according to the UDP protocol specifications in X-Plane version 9. Any X-Plane DATA packets can be sent and received, and any X-Plane DataRefs can be set by sending DREF packets to X-Plane.
Dependencies: EthernetNetIf mbed ConfigFile
Diff: XPlaneUdp/XPlaneUdpDecoder.cpp
- Revision:
- 0:a5d13af495af
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/XPlaneUdp/XPlaneUdpDecoder.cpp Wed Dec 21 22:29:59 2011 +0000
@@ -0,0 +1,69 @@
+#include <stdio.h>
+#include <string.h>
+#include "XPlaneUdp.h"
+#include "XPlaneUdpDecoder.h"
+#include "XPlaneUdpDATA.h"
+
+void XPlaneUdpDecoder::setDebug(bool debug) {
+ _debug = debug;
+}
+
+void XPlaneUdpDecoder::setReverseByteOrder(bool reverseByteOrder) {
+ _reverseByteOrder = reverseByteOrder;
+}
+
+XPlaneUdpMessageType XPlaneUdpDecoder::setUdpBuffer(char * buf, int bufLen) {
+ _udpPacketMsgType = UNKNOWN;
+ _udpBuffer = buf;
+ _udpBufferLen = bufLen;
+ //_udpBuffer[bufLen] = 0; // only need to do this if treating buffer like a string, e.g. printing it
+
+ if (_udpBufferLen >= 5) {
+ if (strncmp(_udpBuffer, "DATA", 4) == 0) {
+ if (_debug) printf("Got DATA pkt \n");
+ _udpPacketMsgType = DATA;
+ }
+ }
+
+ return _udpPacketMsgType;
+}
+
+int XPlaneUdpDecoder::putIntoDATAMap(XPlaneUdpDATAMap & DATAMap, bool filter) {
+ int updateCount = 0;
+
+ if (_udpPacketMsgType != DATA) {
+ return 0;
+ }
+
+ if (filter && (DATAMap.size() == 0)) {
+ return 0;
+ }
+
+ int dataMsgCount = (_udpBufferLen - 5) / XPLANE_DATA_MSG_LENGTH;
+ if (_debug) printf("%d msgs in pkt \n", dataMsgCount);
+ int bufOffset = 5;
+ for (int msgNbr = 0; msgNbr < dataMsgCount; msgNbr++) {
+
+ int index;
+ memcpy(&index, _udpBuffer + bufOffset, 4);
+ if (_reverseByteOrder) {
+ reverse4Bytes((char*) &index);
+ }
+
+ XPlaneUdpDATA *DATAmsg = getXPlaneUdpDATA(DATAMap, index);
+ if (DATAmsg != NULL) {
+ DATAmsg->setAllData(_udpBuffer + bufOffset);
+ updateCount++;
+ }
+ else if (! filter) {
+ DATAmsg = new XPlaneUdpDATA(index, _reverseByteOrder);
+ DATAmsg->setAllData(_udpBuffer + bufOffset);
+ DATAMap[index] = DATAmsg;
+ updateCount++;
+ }
+
+ bufOffset += XPLANE_DATA_MSG_LENGTH;
+ }
+
+ return updateCount;
+}