1 files changed, 173 insertions, 0 deletions
diff --git a/src/ringbuffer.cpp b/src/ringbuffer.cpp
new file mode 100644
index 0000000..7609768
--- /dev/null
+++ b/src/ringbuffer.cpp
@@ -0,0 +1,173 @@
+/***************************************************************************
+                          ringbuffer.cpp  -  description
+                             -------------------
+    begin                : Sun March 21 2004
+    copyright            : (C) 2004 by Martin Witte
+    email                : witte@kawo1.rwth-aachen.de
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "include/ringbuffer.h"
+#include <string.h>
+
+RingBuffer::RingBuffer(size_t size)
+{
+    m_Buffer   = new char [size];
+    m_Size     = size;
+    m_FillSize = 0;
+    m_Start    = 0;
+}
+
+
+RingBuffer::~RingBuffer()
+{
+    delete[] m_Buffer;
+    m_Buffer = NULL;
+    m_Size   = 0;
+}
+
+
+bool RingBuffer::resize(size_t new_size)
+{
+    if (new_size >= m_FillSize && new_size > 0) {
+        char      *newBuffer = new char[new_size];
+        size_t   newFill = 0;
+        while (m_FillSize > 0)
+            newFill += takeData(newBuffer + newFill, m_FillSize);
+
+        delete[] m_Buffer;
+
+        m_FillSize = newFill;
+        m_Start    = 0;
+        m_Buffer   = newBuffer;
+        m_Size     = new_size;
+        return true;
+    }
+    return false;
+}
+
+
+size_t RingBuffer::addData (const char *src, size_t size)
+{
+    size_t written = 0;
+    if (m_Start + m_FillSize < m_Size) {
+        size_t rest = m_Size - m_Start - m_FillSize;
+        if (rest > size)
+            rest = size;
+        memmove (m_Buffer + m_Start + m_FillSize, src, rest);
+        m_FillSize += rest;
+        written    += rest;
+        size       -= rest;
+        src        += rest;
+    }
+    if (size > 0 && m_FillSize < m_Size) {
+        size_t rest = size;
+        if (rest > m_Size - m_FillSize)
+            rest = m_Size - m_FillSize;
+        memmove(m_Buffer + m_Start + m_FillSize - m_Size, src, rest);
+        m_FillSize += rest;
+        written    += rest;
+    }
+    return written;
+}
+
+
+size_t RingBuffer::takeData(char *dst, size_t size)
+{
+    size_t read = 0;
+    while (m_FillSize > 0 && size > 0) {
+        size_t n = size;
+        if (n > m_FillSize)
+            n = m_FillSize;
+        if (n > m_Size - m_Start)
+            n = m_Size - m_Start;
+        memmove (dst, m_Buffer + m_Start, n);
+        m_FillSize -= n;
+        m_Start    += n;
+        read       += n;
+        size       -= n;
+        if (m_Start >= m_Size)
+            m_Start -= m_Size;
+
+    }
+    return read;
+}
+
+
+char      *RingBuffer::getFreeSpace(size_t &size)
+{
+    if (m_FillSize == m_Size) {
+        size = 0;
+        return NULL;
+    }
+
+    if (m_Start + m_FillSize >= m_Size) {
+        size = m_Size - m_FillSize;
+        return m_Buffer + m_Start + m_FillSize - m_Size;
+    } else {
+        size = m_Size - m_Start - m_FillSize;
+        return m_Buffer + m_Start + m_FillSize;
+    }
+}
+
+
+size_t   RingBuffer::removeFreeSpace(size_t size)
+{
+    if (m_FillSize == m_Size)
+        return 0;
+
+    if (m_Start + m_FillSize >= m_Size) {
+        if (size > m_Size - m_FillSize)
+            size = m_Size - m_FillSize;
+        m_FillSize += size;
+        return size;
+    } else {
+        if (m_Start + m_FillSize + size >= m_Size)
+            size = m_Size - m_Start - m_FillSize;
+        m_FillSize += size;
+        return size;
+    }
+}
+
+
+char      *RingBuffer::getData(size_t &size)
+{
+    if (m_Start + m_FillSize >= m_Size) {
+        size = m_Size - m_Start;
+    } else {
+        size = m_FillSize;
+    }
+    return m_Buffer + m_Start;
+}
+
+
+size_t   RingBuffer::removeData(size_t size)
+{
+    size_t n = 0;
+    if (size > m_FillSize)
+        size = m_FillSize;
+    if (m_Start + size >= m_Size) {
+        n = m_Size - m_Start;
+        m_Start = 0;
+    } else {
+        m_Start += size;
+        n = size;
+    }
+    m_FillSize -= n;
+    return n;
+}
+
+
+void RingBuffer::clear()
+{
+    m_Start    = 0;
+    m_FillSize = 0;
+}