aboutsummaryrefslogtreecommitdiff
path: root/daemon/Fifo.h
blob: 51e2bcd6a7f888662b9ba664abc7349ca8c483e9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
/**
 * Copyright (C) ARM Limited 2010-2012. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef	__FIFO_H__
#define	__FIFO_H__

#include <semaphore.h>

// Number of buffers allowed with large buffer mode
#define FIFO_BUFFER_LIMIT	64

class Fifo {
public:
	Fifo(int numBuffers, int bufferSize);
	~Fifo();
	int depth(void);
	int numReadToWriteBuffersFilled();
	int numWriteToReadBuffersFilled();
	int numReadToWriteBuffersEmpty() {return depth() - numReadToWriteBuffersFilled();}
	int numWriteToReadBuffersEmpty() {return depth() - numWriteToReadBuffersFilled();}
	char* start();
	char* write(int length);
	char* read(int* length);

private:
	int		mNumBuffers;
	int		mBufferSize;
	int		mWriteCurrent;
	int		mReadCurrent;
	sem_t	mReadToWriteSem[FIFO_BUFFER_LIMIT];
	sem_t	mWriteToReadSem[FIFO_BUFFER_LIMIT];
	char*	mBuffer[FIFO_BUFFER_LIMIT];
	int		mLength[FIFO_BUFFER_LIMIT];
};

#endif 	//__FIFO_H__