intermediate: restructure buffer handling

lib/queue/GwBuffer.h

@@ -4,6 +4,7 @@
 #include <stdint.h>
 #include "GwLog.h"
 
+class GwBuffer;
 class GwBufferWriter{
     public:
         int id=0; //can be set be users
@@ -12,11 +13,19 @@ class GwBufferWriter{
         virtual ~GwBufferWriter(){};
 };
 
+class GwMessageFetcher{
+    public:
+        int id=0;
+        virtual bool handleBuffer(GwBuffer *buffer)=0;
+        virtual size_t fetchMessageToBuffer(GwBuffer *gwbuffer,uint8_t *buffer, size_t bufferLen,char delimiter);  
+};
+
 /**
  * an implementation of a
  * buffer to safely inserte data if it fits
  * and to write out data if possible
  */
+typedef size_t (*GwBufferHandleFunction)(uint8_t *buffer, size_t len, void *param);
 class GwBuffer{
     public:
         static const size_t TX_BUFFER_SIZE=1620; // app. 20 NMEA messages
@@ -36,25 +45,26 @@ class GwBuffer{
         }
         GwLog *logger;
         void lp(const char *fkt,int p=0);
-        /**
-         * find the first occurance of x in the buffer, -1 if not found
-         */
-        int findChar(char x);
     public:
         GwBuffer(GwLog *logger,size_t bufferSize);
         ~GwBuffer();
-        void reset();
+        void reset(String reason="");
         size_t freeSpace();
         size_t usedSpace();
         size_t addData(const uint8_t *data,size_t len,bool addPartial=false);
+        size_t fillData(int maxLen,GwBufferHandleFunction handler, void *param);
         int read();
         int peek();
+        size_t fetchData(int maxLen,GwBufferHandleFunction handler, void *param);
         /**
          * write some data to the buffer writer
          * return an error if the buffer writer returned < 0
          */
         WriteStatus fetchData(GwBufferWriter *writer, int maxLen=-1,bool errorIf0 = true);
-
+        /**
+         * find the first occurance of x in the buffer, -1 if not found
+         */
+        int findChar(char x);
         WriteStatus fetchMessage(GwBufferWriter *writer,char delimiter,bool emptyIfFull=true);
 };