Changeset 1311 in ntrip

Timestamp:

Dec 20, 2008, 1:32:04 PM (15 years ago)

Author:

mervart

Message:

* empty log message *

Location:

trunk/BNC/GPSS

Files:

• gpssDecoder.cpp (modified) (2 diffs)
• gpssDecoder.h (modified) (1 diff)

trunk/BNC/GPSS/gpssDecoder.cpp

@@ -18 +18 @@
 #include "gpssDecoder.h"
 
+#define MODE_SEARCH     0
+#define MODE_TYPE       1
+#define MODE_EPOCH      2
+#define MODE_EPOCH_BODY 3
+#define MODE_EPOCH_CRC  4
+#define MODE_EPOCH_ETX  5
+#define MODE_EPH        6
+#define MODE_EPH_BODY   7
+#define MODE_EPH_CRC    8
+#define MODE_EPH_ETX    9
+#define MAX_PRN         32
+
 using namespace std;
+
+typedef struct epochHeader {
+  double t_epoch;
+  int    n_svs;
+} EPOCHHEADER;
 
 // Constructor
 ////////////////////////////////////////////////////////////////////////////
 gpssDecoder::gpssDecoder() : GPSDecoder() {
+  _mode = MODE_SEARCH;
 }
 
@@ -32 +50 @@
 // 
 ////////////////////////////////////////////////////////////////////////////
-t_irc gpssDecoder::Decode(char* buffer, int bufLen, vector<string>& errmsg) {
+t_irc gpssDecoder::Decode(char* data, int dataLen, vector<string>& errmsg) {
+
   errmsg.clear();
 
+  _buffer.append(data, dataLen);
+
+  bool     haveEpoch  = false;
+  bool     haveEph    = false;
+  int      recordSize = 0;
+  unsigned offset     = 0;
+
+  EPOCHHEADER   epochHdr;
+  t_obsInternal gpsObs[MAX_PRN];
+  gpsephemeris  gpsEph;
+
+  for (offset = 0; offset < _buffer.size(); offset++) { 
+
+    switch(_mode) {
+
+      case MODE_SEARCH:
+        if (_buffer[offset] == 0x02) {
+          _mode = MODE_TYPE;
+        }
+        continue;
+
+      case MODE_TYPE:
+        if        (_buffer[offset] == 0x00) {
+          _mode = MODE_EPOCH;
+        } else if (_buffer[offset] == 0x01) {
+          _mode = MODE_EPH;
+        } else {
+          errmsg.push_back("Unknown record type");
+          _mode = MODE_SEARCH;
+        }
+        continue;
+
+      case MODE_EPOCH:
+      case MODE_EPH:
+        if (offset+sizeof(recordSize) > _buffer.size()) {
+          errmsg.push_back("Record size too large (A)");
+          _mode = MODE_SEARCH;
+        } else {
+          memcpy(&_buffer[offset], &recordSize, sizeof(recordSize)); 
+          if (_mode == MODE_EPOCH) {
+            _mode = MODE_EPOCH_BODY;
+          }
+          if (_mode == MODE_EPH) {
+            _mode = MODE_EPH_BODY;
+          }
+          offset += sizeof(recordSize) - 1;
+        }
+        continue;
+
+      case MODE_EPOCH_BODY:
+        if (offset + recordSize > _buffer.size()) {
+          errmsg.push_back("Record size too large (B)");
+          _mode = MODE_SEARCH;
+        } else {
+          ///          memcpy(&_buffer[offset], epoch, recordSize);
+          offset += recordSize - 1;
+          _mode = MODE_EPOCH_CRC;
+        }
+        continue;
+
+      case MODE_EPH_BODY:
+        if (offset + recordSize > _buffer.size()) {
+          errmsg.push_back("Record size too large (B)");
+          _mode = MODE_SEARCH;
+        } else {
+          ///          memcpy(&_buffer[offset], eph, recordSize);
+          offset += recordSize - 1;
+          _mode = MODE_EPH_CRC;
+        }
+        continue;
+
+      case MODE_EPOCH_CRC:
+        _mode = MODE_EPOCH_ETX; // TODO: CRC check
+        continue;
+
+      case MODE_EPH_CRC:
+        _mode = MODE_EPH_ETX;   // TODO: CRC check
+        continue;
+
+      case MODE_EPOCH_ETX:
+        haveEpoch = true;
+        _mode = MODE_SEARCH;
+        continue;
+
+      case MODE_EPH_ETX:
+        haveEph = true;
+        _mode = MODE_SEARCH;
+        continue;
+    }
+
+    if (haveEpoch) {
+      haveEpoch = false;
+    }
+
+    if (haveEph) {
+      haveEph = false;
+    }
+  }
 }

trunk/BNC/GPSS/gpssDecoder.h

@@ -10 +10 @@
 class gpssDecoder : public QObject, public GPSDecoder {
 Q_OBJECT
+
  public:
   gpssDecoder();
   virtual ~gpssDecoder();
   virtual t_irc Decode(char* buffer, int bufLen, std::vector<std::string>& errmsg);
+
  signals:
   void newMessage(QByteArray msg, bool showOnScreen);
   void newGPSEph(gpsephemeris* gpseph);
+
  private:
+  int         _mode;
+  std::string _buffer;
 } ;