initial commit

ringbuffer.h

@@ -0,0 +1,112 @@
+/*UVOS*/
+
+/* This file is part of TelemetrySystem.
+ *
+ * TelemetrySystem is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License (LGPL) version 3 as published by
+ * the Free Software Foundation.
+ *
+ * TelemetrySystem is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with TelemetrySystem.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#pragma once
+
+#include <stdint.h>
+
+template < int BUFFER_SIZE >
+class RingBuffer
+{
+private:
+    
+    uint_fast16_t _headIndex = 0;
+    uint_fast16_t _tailIndex = 0;
+    uint8_t _buffer[BUFFER_SIZE];
+    
+public:
+    
+    RingBuffer()
+    {
+        flush();
+    }
+    
+    uint_fast16_t remaining()
+    {
+        return (_headIndex-_tailIndex);
+    }
+    
+    bool isOverun(uint_fast16_t margin = 0)
+    {
+       return remaining() >= BUFFER_SIZE - margin;
+    }
+    
+    bool isEmpty()
+    {
+        return _tailIndex >= _headIndex;
+    }
+    
+    uint8_t read()
+    {
+        if(!isEmpty())
+        {
+            _tailIndex++;
+            return _buffer[(_tailIndex - 1) % BUFFER_SIZE];
+        }
+        else return '\0';
+    }
+    
+    unsigned int read( uint8_t* buffer, unsigned int length )
+    {
+        unsigned int i = 0;
+        for(; i < length && !isEmpty(); i++)
+        {
+            buffer[i] = read();
+        }
+        return i;
+    }
+    
+    void write( uint8_t in )
+    {
+        if (_headIndex - BUFFER_SIZE > 0 && _tailIndex - BUFFER_SIZE > 0)
+        {
+            _headIndex -= BUFFER_SIZE;
+            _tailIndex -= BUFFER_SIZE;
+        }
+        _buffer[_headIndex % BUFFER_SIZE] = in;
+        _headIndex++;
+    }
+    
+    void write( uint8_t* buffer, unsigned int length )
+    {
+        for(uint8_t i = 0; i < length; i++) write(buffer[i]);
+    }
+    
+    void flush()
+    {
+        _headIndex = 0;
+        _tailIndex = 0;
+        for(int i = 0; i < BUFFER_SIZE; i++) _buffer[i] = ' ';
+    }
+    
+    unsigned int getString(uint8_t terminator, char* buffer, const unsigned int bufferLength)
+    {
+        unsigned int i = 0;
+        for(; i <= remaining() && i <= BUFFER_SIZE && _buffer[(_tailIndex+i) % BUFFER_SIZE] != terminator; i++);
+        
+        if( i < remaining() && i > 0)
+        {
+            if(i > bufferLength-1) i = bufferLength-1;
+            read((uint8_t*)buffer, i);
+            buffer[i]='\0';
+            _tailIndex++;
+        }
+        else if(i == 0) _tailIndex++;
+        else i = 0;
+        
+        return i;
+    }
+};