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authorChristian Gromm <christian.gromm@microchip.com>2016-12-08 16:46:07 +0100
committerChristian Gromm <christian.gromm@microchip.com>2016-12-08 16:46:07 +0100
commit0a28683a1ff9f3975c8b68b15017cf342bab5f3d (patch)
tree2f350b709db4d45532fc0624cfce22ec11e43ccf /Src/Multiplexer/RingBuffer.h
parent18c9e9fc0000861257ab06f6a033612b0c567674 (diff)
src: vod-server: import sources
This patch adds the source tree of the Video-On-Demand server and its configuration scripts. Change-Id: I6db8c43d46c7450baf117a541bd7153496dbcd4c Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
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1 files changed, 187 insertions, 0 deletions
diff --git a/Src/Multiplexer/RingBuffer.h b/Src/Multiplexer/RingBuffer.h
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+/*
+ * Video On Demand Samples
+ *
+ * Copyright (C) 2015 Microchip Technology Germany II GmbH & Co. KG
+ *
+ * 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * You may also obtain this software under a propriety license from Microchip.
+ * Please contact Microchip for further information.
+ *
+ */
+
+/*----------------------------------------------------------*/
+/*! \file
+ * \brief This file contains the CRingBuffer class.
+ */
+/*----------------------------------------------------------*/
+
+#ifndef CRINGBUFFER_H
+#define CRINGBUFFER_H
+
+#include "Console.h"
+
+
+/*----------------------------------------------------------*/
+/*! \brief Class providing a ring buffer. One thread can
+* write to the buffer while another thread is reading
+* from it. This class has highest performance for
+* synchronization, since it is not using mutexes.
+*
+* LIMITATIONS:
+* - only one thread can read
+* - only one thread can write
+* - the ring buffer size needs to be aligned to
+* read, write block size
+*
+* Violating any limitation will lead to unpredictable
+* results.
+*/
+/*----------------------------------------------------------*/
+class CRingBuffer
+{
+ uint8_t *m_pBuf;
+ uint32_t m_nWriteTot; // total bytes written to ring buffer
+ uint32_t m_nReadTot; // total bytes read from ring buffer
+ uint32_t m_nWritePos; // memory write position
+ uint32_t m_nReadPos; // memory read position
+ uint32_t m_nReadLen; // bytes per read
+ uint32_t m_nWriteLen; // bytes per write
+ uint32_t m_nBufLen; // bytes of buffer
+
+public:
+ /*----------------------------------------------------------*/
+ /*! \brief constructs a ring buffer instance
+ * \param nReadLen - read block size in bytes
+ * \param nWriteLen - write block size in bytes
+ * \param nWriteBlocks - total buffer size counted in write
+ * blocks
+ */
+ /*----------------------------------------------------------*/
+ CRingBuffer(uint32_t nReadLen, uint32_t nWriteLen, uint32_t nWriteBlocks)
+ : m_nWriteTot(0)
+ , m_nReadTot(0)
+ , m_nWritePos(0)
+ , m_nReadPos(0)
+ , m_nReadLen(nReadLen)
+ , m_nWriteLen(nWriteLen)
+ , m_nBufLen(nWriteBlocks*nWriteLen)
+ {
+ if ( 0 != (m_nBufLen % m_nReadLen) ) {
+ ConsolePrintf( PRIO_ERROR, RED"! ring size needs to be dividable by read block size"RESETCOLOR);
+ throw (-10);
+ }
+ m_pBuf = new uint8_t[m_nBufLen];
+
+ if (NULL == m_pBuf) {
+ ConsolePrintf( PRIO_ERROR, RED"! out of memory"RESETCOLOR);
+ throw (-10);
+ }
+ }
+
+
+
+ /*----------------------------------------------------------*/
+ /*! \brief destructs ring buffer instance
+ */
+ /*----------------------------------------------------------*/
+ ~CRingBuffer()
+ {
+ delete m_pBuf;
+ }
+
+
+
+ /*----------------------------------------------------------*/
+ /*! \brief checks if there is enough memory available to
+ * write a chunk of data to the ring buffer
+ * \return true, if can be written
+ */
+ /*----------------------------------------------------------*/
+ bool GetCanWrite()
+ {
+ uint32_t nFilled = m_nWriteTot - m_nReadTot;
+ return nFilled < m_nBufLen - m_nWriteLen;
+ }
+
+
+
+ /*----------------------------------------------------------*/
+ /*! \brief checks if there is enough memory available to
+ * read a chunk of data from the ring buffer
+ * \return true, if can be read
+ */
+ /*----------------------------------------------------------*/
+ bool GetCanRead()
+ {
+ uint32_t nFilled = m_nWriteTot - m_nReadTot;
+ return nFilled >= m_nReadLen;
+ }
+
+
+
+ /*----------------------------------------------------------*/
+ /*! \brief gets pointer to current read position
+ * \return pointer to current read position
+ */
+ /*----------------------------------------------------------*/
+ uint8_t *GetReadPos()
+ {
+ return m_pBuf + m_nReadPos;
+ }
+
+
+
+ /*----------------------------------------------------------*/
+ /*! \brief gets pointer to current write position
+ * \return pointer to current write position
+ */
+ /*----------------------------------------------------------*/
+ uint8_t *GetWritePos()
+ {
+ return m_pBuf + m_nWritePos;
+ }
+
+
+
+ /*----------------------------------------------------------*/
+ /*! \brief called after a chunk of data has been written
+ * to the ring buffer
+ */
+ /*----------------------------------------------------------*/
+ void WriteDone()
+ {
+ m_nWriteTot += m_nWriteLen;
+ m_nWritePos += m_nWriteLen;
+ if (m_nBufLen == m_nWritePos)
+ m_nWritePos = 0;
+ }
+
+
+
+ /*----------------------------------------------------------*/
+ /*! \brief called after a chunk of data has been read
+ * from the ring buffer
+ */
+ /*----------------------------------------------------------*/
+ void ReadDone()
+ {
+ m_nReadTot += m_nReadLen;
+ m_nReadPos += m_nReadLen;
+ if (m_nBufLen == m_nReadPos)
+ m_nReadPos = 0;
+ }
+};
+
+#endif