Switch audio fifo queue to a faster non-STL one.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@718 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Core/Common/Src/FixedSizeQueue.h

@@ -0,0 +1,81 @@
+// Copyright (C) 2003-2008 Dolphin Project.
+
+// 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, version 2.0.
+
+// 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 2.0 for more details.
+
+// A copy of the GPL 2.0 should have been included with the program.
+// If not, see http://www.gnu.org/licenses/
+
+// Official SVN repository and contact information can be found at
+// http://code.google.com/p/dolphin-emu/
+
+#ifndef _FIXED_SIZE_QUEUE_H
+#define _FIXED_SIZE_QUEUE_H
+
+// STL-look-a-like interface, but name is mixed case to distinguish it clearly from the
+// real STL classes.
+
+// Not fully featured, no safety checking yet. Add features as needed.
+
+// TODO: "inline" storage?
+
+template <class T, int N>
+class FixedSizeQueue
+{
+	T *storage;
+	int head;
+	int tail;
+	int count;  // sacrifice 4 bytes for a simpler implementation. may optimize away in the future.
+
+	// Make copy constructor private for now.
+	FixedSizeQueue(FixedSizeQueue &other) {	}
+
+public:
+	FixedSizeQueue()
+	{
+		head = 0;
+		tail = 0;
+		storage = new T[N];
+	}
+
+	~FixedSizeQueue()
+	{
+		delete storage;
+	}
+
+	void push(T t) {
+		storage[tail] = t;
+		tail++;
+		if (tail == N)
+			tail = 0;
+		count++;
+	}
+
+	void pop() {
+		head++;
+		if (head == N)
+			head = 0;
+		count--;
+	}
+
+	T pop_front() {
+		const T &temp = storage[head];
+		pop();
+		return temp;
+	}
+
+	T &front() { return storage[head]; }
+	const T &front() const { return storage[head]; }
+
+	size_t size() const {
+		return count;
+	}
+};
+
+#endif  // _FIXED_SIZE_QUEUE_H