1 files changed, 420 insertions, 0 deletions
diff --git a/mpeglib/lib/input/simpleRingBuffer.cpp b/mpeglib/lib/input/simpleRingBuffer.cpp
new file mode 100644
index 00000000..71c92329
--- /dev/null
+++ b/mpeglib/lib/input/simpleRingBuffer.cpp
@@ -0,0 +1,420 @@
+/*
+  a thread safe ring buffer without dependencies
+  Copyright (C) 1999  Martin Vogt
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Library General Public License as published by
+  the Free Software Foundation.
+
+  For more information look at the file COPYRIGHT in this package
+
+ */
+
+
+
+
+#include "simpleRingBuffer.h"
+#include <string.h>
+
+#include <iostream>
+
+using namespace std;
+
+static int instanceCnt=0;
+
+SimpleRingBuffer::SimpleRingBuffer(int size,int minLinSize) {
+  abs_thread_mutex_init(&mut);
+  abs_thread_cond_init(&dataCond);
+  abs_thread_cond_init(&spaceCond);
+
+  instance=instanceCnt;
+  instanceCnt++;
+  this->size=size;
+  startPos=(char*)malloc(size);
+  readPos=startPos;
+  writePos=startPos;
+  lockPos=startPos;
+
+  lockgrade=0;
+  fillgrade=0;
+  linAvail=size;
+  lastPos=(startPos+size-1);
+  eofPos=lastPos+1;
+
+  canWrite=size;
+  canRead=0;
+
+  minLinBuf=new char[minLinSize];
+  this->minLinBufSize=minLinSize;
+  waitMinData=0;
+  waitMinSpace=0;
+  lWaitForData=false;
+  lWaitForSpace=false;
+
+  readBytes=0;
+  writeBytes=0;
+
+  lCanWaitForData=true;
+  lCanWaitForSpace=true;
+}
+
+
+SimpleRingBuffer::~SimpleRingBuffer() {
+  // The user of this class must take care that the threads
+  // have exited!
+  free(startPos);
+  delete [] minLinBuf;
+  abs_thread_mutex_destroy(&mut);
+  abs_thread_cond_destroy(&dataCond);
+  abs_thread_cond_destroy(&spaceCond);
+}
+  
+
+int SimpleRingBuffer::getSize() {
+  return size;
+}
+
+
+int SimpleRingBuffer::getWriteArea(char* &ptr,int &size) {
+
+  // When we are in this area the following
+  // can happen by the other thread
+  // fillgrade is decreased (because reader fowards)
+  // readPos is changed.
+
+  ptr=writePos;
+  size=canWrite;
+
+  return size;
+}
+
+
+void SimpleRingBuffer::updateCanWrite() {
+  if (lockPos < writePos) {
+    canWrite=eofPos-writePos;
+    //printf("1 c:%d l:%p w:%p",canWrite,lockPos,writePos);
+  } else if (lockPos > writePos) {
+    canWrite=lockPos-writePos;
+    //printf("2 c:%d l:%p w:%p",canWrite,lockPos,writePos);
+  } else {
+    if (fillgrade > 0) {
+      canWrite=0;
+    } else {
+      canWrite=eofPos-writePos;
+    }
+    //printf("2 c:%d ",canWrite);
+    
+  }
+  if (canWrite < 0) {
+    printf("error canWrite:%d fill:%d lock:%p start:%p eof:%p write:%p\n",
+           canWrite,fillgrade,lockPos,startPos,eofPos,writePos);
+  }
+
+} 
+
+
+void SimpleRingBuffer::updateCanRead() {
+  canRead=fillgrade-lockgrade;
+  int currentSpace=size-fillgrade;
+  if (currentSpace >= waitMinSpace) {
+    abs_thread_cond_signal(&spaceCond);
+  } 
+  if (canRead < 0) {
+    printf("error canRead:%d fillgrade:%d lockgrade:%d \n",
+           canRead,fillgrade,lockgrade);
+  }
+ 
+} 
+
+
+void SimpleRingBuffer::forwardLockPtr(int nBytes) {
+  abs_thread_mutex_lock(&mut);
+
+  if (fillgrade < lockgrade) {
+    printf("1:fillgrade:%d < lockgrade:%d\n",fillgrade,lockgrade);
+  }
+  fillgrade-=nBytes;
+  lockgrade-=nBytes;
+  if (fillgrade < lockgrade) {
+    printf("2:fillgrade:%d < lockgrade:%d nBytes:%d\n",
+	   fillgrade,lockgrade,nBytes);
+  }
+  lockPos=lockPos+nBytes;
+  if (lockPos > lastPos) {   // we expects that we had a linAvail part
+    // if user forwards more than buffer boundary
+    nBytes=lockPos-lastPos;
+    lockPos=startPos+nBytes-1;
+  }
+  updateCanWrite();
+  updateCanRead();
+
+  abs_thread_mutex_unlock(&mut);
+  return;
+}
+
+
+void SimpleRingBuffer::forwardWritePtr(int nBytes) {
+  abs_thread_mutex_lock(&mut);
+  
+  fillgrade=fillgrade+nBytes;
+  if (fillgrade < lockgrade) {
+    printf("3:fillgrade:%d < lockgrade:%d nBytes:%d\n",
+	   fillgrade,lockgrade,nBytes);
+  }
+  writeBytes+=nBytes;
+  writePos=writePos+nBytes;
+  if(writePos >= eofPos) {
+    if (writePos == eofPos) {
+      writePos=startPos;
+    } else {
+      cout << "writePos > eofPos ! forward error:"<<(eofPos-writePos)
+	   <<" bytes"<<endl;
+    }
+  }
+
+  updateCanWrite();
+  updateCanRead();
+  if (fillgrade >= waitMinData) {
+    abs_thread_cond_signal(&dataCond);
+  }
+  abs_thread_mutex_unlock(&mut);
+}
+
+
+int SimpleRingBuffer::waitForSpace(int bytes){
+  abs_thread_mutex_lock(&mut);
+  int back=0;
+  waitMinSpace=bytes;
+  if (waitMinSpace > size) {
+    waitMinSpace=size;
+  }
+  if (waitMinSpace < 0) {
+    cout << "negative waitForSpace"<<endl;
+    waitMinSpace=0;
+  }
+  int currentSpace=size-fillgrade;
+  if (lCanWaitForSpace) {
+    if (currentSpace < waitMinSpace) {
+      lWaitForSpace=true;
+      // it is not possible to wait for data/space simultanously
+      if (lWaitForData == true) {
+	abs_thread_cond_signal(&dataCond);
+      }
+      abs_thread_cond_wait(&spaceCond,&mut);
+      lWaitForSpace=false;
+    }
+  }
+  if (size-fillgrade >= waitMinSpace) {
+    back=1;
+  }
+  abs_thread_mutex_unlock(&mut);
+  return back;
+}
+
+
+void SimpleRingBuffer::exitWaitForSpace(){
+  abs_thread_mutex_lock(&mut);
+  abs_thread_cond_signal(&spaceCond);
+  abs_thread_mutex_unlock(&mut);
+}
+
+void SimpleRingBuffer::setCanWaitForSpace(int lCanWaitForSpace) {
+  abs_thread_mutex_lock(&mut);
+  this->lCanWaitForSpace=lCanWaitForSpace;
+  abs_thread_cond_signal(&spaceCond);
+  abs_thread_mutex_unlock(&mut);
+
+}
+  
+  
+
+void SimpleRingBuffer::forwardReadPtr(int nBytes) {
+  abs_thread_mutex_lock(&mut);
+  readBytes+=nBytes;
+  readPos+=nBytes;
+  linAvail=linAvail-nBytes;
+  lockgrade+=nBytes;
+  if (readPos > lastPos) {   // we expects that we had a linAvail part
+    // if user forwards more than buffer boundary
+    nBytes=readPos-lastPos;
+    readPos=startPos+nBytes-1;
+    linAvail=lastPos+1-readPos;
+  }
+  if (fillgrade < lockgrade) {
+    printf("5:fillgrade:%d < lockgrade:%d nBytes:%d\n",
+	   fillgrade,lockgrade,nBytes);
+  }
+  updateCanRead();
+  abs_thread_mutex_unlock(&mut);
+}
+
+
+
+int SimpleRingBuffer::getReadArea(char* &ptr,int &readSize) {
+  int pSize=readSize;
+  ptr=readPos;
+
+  if (canRead == 0) {
+    readSize=0;
+    return 0;
+  }
+  if (pSize < 0) { 
+    cout << "Generic Memory Info invalid"<<endl;
+    pSize=size/2;
+  }
+  //
+  // Now the part the we deliver a minimum buffer if it is
+  // possible
+  //
+
+  if ( (pSize > linAvail) &&
+       (minLinBufSize >linAvail) &&
+       (canRead > linAvail) ) {
+    int copySize;
+    copySize=canRead;  // we cannot copy more than this
+    if (copySize > pSize) { // if it is too much reduche it
+      copySize=pSize;
+    }
+    if (copySize > minLinBufSize) { // if it does not fit in buffer->reduce
+      copySize=minLinBufSize;
+    }
+    memcpy(minLinBuf,readPos,linAvail);
+    memcpy(minLinBuf+linAvail,startPos,copySize-linAvail);
+    readSize=copySize;
+    ptr=minLinBuf;
+    return copySize;
+  }
+
+  // linAvail part end
+
+  int copyBytes=linAvail;
+  if (canRead < copyBytes) {
+    copyBytes=canRead;
+  }
+  if (copyBytes >= pSize) {
+    readSize=pSize;
+  } else {
+    readSize=copyBytes;
+  }
+  return readSize;
+}
+
+
+
+void SimpleRingBuffer::exitWaitForData(){
+  abs_thread_mutex_lock(&mut);
+  abs_thread_cond_signal(&dataCond);
+  abs_thread_mutex_unlock(&mut);
+}
+
+
+
+int SimpleRingBuffer::waitForData(int bytes){
+  abs_thread_mutex_lock(&mut);
+  int back=0;
+  waitMinData=bytes;
+  if (waitMinData > size) {
+    waitMinData=size;
+  }
+  if (waitMinData < 0) {
+    cout << "negative waitForData"<<endl;
+    waitMinData=0;
+  }
+  if (lCanWaitForData) {
+    if (fillgrade < waitMinData) {
+      lWaitForData=true;
+      // it is not possible to wait for data space simultanously
+      if (lWaitForSpace == true) {
+	abs_thread_cond_signal(&spaceCond);
+      }
+      abs_thread_cond_wait(&dataCond,&mut);
+      lWaitForData=false;
+    }
+  }
+  if (fillgrade >= waitMinData) {
+    back=1;
+  }
+  abs_thread_mutex_unlock(&mut);
+  return back;
+}
+
+int SimpleRingBuffer::getCanWaitForData() {
+  return lCanWaitForData;
+}
+  
+
+void SimpleRingBuffer::setCanWaitForData(int lCanWaitForData) {
+  abs_thread_mutex_lock(&mut);
+  this->lCanWaitForData=lCanWaitForData;
+  abs_thread_cond_signal(&dataCond);
+  abs_thread_mutex_unlock(&mut);
+
+}
+
+void SimpleRingBuffer::emptyBuffer() {
+  abs_thread_mutex_lock(&mut);
+  writePos=readPos;
+  if (fillgrade < lockgrade) {
+    printf("4:fillgrade:%d < lockgrade:%d\n",fillgrade,lockgrade);
+  }
+  linAvail=lastPos+1-writePos;
+  fillgrade=lockgrade;
+  updateCanRead();
+  updateCanWrite();
+  readBytes=0;
+  writeBytes=0;
+  if (size-fillgrade >= waitMinSpace) {
+    abs_thread_cond_signal(&spaceCond);
+  }
+  if (fillgrade >= waitMinData) {
+    abs_thread_cond_signal(&dataCond);
+  }
+  abs_thread_mutex_unlock(&mut);
+}
+
+
+int SimpleRingBuffer::getFillgrade() {
+  return fillgrade;
+}
+
+
+int SimpleRingBuffer::getReadBytes() {
+  return readBytes;
+}
+
+
+int SimpleRingBuffer::getWriteBytes() {
+  return writeBytes;
+}
+
+
+int SimpleRingBuffer::getFreeRead() {
+  return fillgrade;
+}
+
+int SimpleRingBuffer::getFreeWrite() {
+  return size-fillgrade;
+}
+
+void SimpleRingBuffer::resizeBuffer(int changeSize) {
+  abs_thread_mutex_lock(&mut);
+  int lPos=lockPos-startPos;
+  int wPos=writePos-startPos;
+  int rPos=readPos-startPos;
+  startPos=(char *)realloc(startPos,changeSize);
+  size=changeSize;
+  readPos=startPos+lPos;
+  writePos=startPos+wPos;
+  lockPos=startPos+rPos;
+
+  lastPos=(startPos+size-1);
+  eofPos=lastPos+1;
+
+  linAvail=lastPos+1-readPos;
+
+  updateCanWrite();
+  updateCanRead();
+  abs_thread_mutex_unlock(&mut);
+
+
+}