1 files changed, 108 insertions, 0 deletions
diff --git a/mpeglib/lib/util/abstract/threadQueue.cpp b/mpeglib/lib/util/abstract/threadQueue.cpp
new file mode 100644
index 00000000..1b130ba9
--- /dev/null
+++ b/mpeglib/lib/util/abstract/threadQueue.cpp
@@ -0,0 +1,108 @@
+/*
+  fifo waitqueue for threads.(Multi-in, single out)
+  Copyright (C) 2000  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 "threadQueue.h"
+
+#define _MAX_THREAD_IN_QUEUE 5
+
+#include <iostream>
+
+using namespace std;
+
+//
+// WaitThreadEntry class [START]
+//
+
+WaitThreadEntry::WaitThreadEntry() {
+  abs_thread_cond_init(&waitCond);
+}
+
+
+WaitThreadEntry::~WaitThreadEntry() {
+  abs_thread_cond_destroy(&waitCond);
+}
+
+//
+// WaitThreadEntry class [END]
+//
+
+
+ThreadQueue::ThreadQueue() {
+  waitThreadEntries=new WaitThreadEntry* [_MAX_THREAD_IN_QUEUE];
+  int i;
+  for(i=0;i<_MAX_THREAD_IN_QUEUE;i++) {
+    waitThreadEntries[i]=new WaitThreadEntry();
+  }
+  abs_thread_mutex_init(&queueMut);
+  insertPos=0;
+  removePos=0;
+  size=0;
+}
+
+
+ThreadQueue::~ThreadQueue() {
+  abs_thread_mutex_lock(&queueMut);
+  if (size != 0) {
+    cout << "Aieee! Make sure that all threads are out of ThreadQueue"<<endl;
+    exit(0);
+  }
+  int i;
+  for(i=0;i<_MAX_THREAD_IN_QUEUE;i++) {
+    delete waitThreadEntries[i];
+  }
+  delete [] waitThreadEntries;
+  abs_thread_mutex_unlock(&queueMut);
+  abs_thread_mutex_destroy(&queueMut);
+}
+
+
+void ThreadQueue::waitForExclusiveAccess() {
+  abs_thread_mutex_lock(&queueMut);
+  if (size == 0) {
+    abs_thread_mutex_unlock(&queueMut);
+    return;
+  }
+  // wait
+  size++;
+  if (size == _MAX_THREAD_IN_QUEUE) {
+    cout << "Aieee! ThreadQueue can only buffer:"<<_MAX_THREAD_IN_QUEUE<<endl;
+    exit(0);
+  }
+  abs_thread_cond_t* waitCond=&(waitThreadEntries[insertPos]->waitCond);
+  insertPos++;
+  // wrap counter
+  if (insertPos == _MAX_THREAD_IN_QUEUE) {
+    insertPos=0;
+  }
+  abs_thread_cond_wait(waitCond,&queueMut);
+  abs_thread_mutex_unlock(&queueMut);
+}
+
+
+void ThreadQueue::releaseExclusiveAccess() {
+  abs_thread_mutex_lock(&queueMut);
+  if (size == 0) {
+    abs_thread_mutex_unlock(&queueMut);
+    return;
+  } 
+  // wake up next thread
+  abs_thread_cond_t* waitCond=&(waitThreadEntries[removePos]->waitCond);
+  removePos++;
+  // wrap counter
+  if (removePos == _MAX_THREAD_IN_QUEUE) {
+    removePos=0;
+  }
+  size--;
+  abs_thread_cond_signal(waitCond);
+  abs_thread_mutex_unlock(&queueMut);
+}
+