/* Linux 
* --Mao
*
* 播放音頻文件要用ioctl函數設置使播放參數與音頻文件相同
* 設置聲卡采樣頻率 arg = 16; ioctl(handler,SOUND_PCM_WRITE_BITS,&arg);
*
*
*
*/

#include <stdio.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <unistd.h>
#include <linux/soundcard.h>

#define Audio_Device "/dev/dsp"

	/*
	不同的聲音有不同的播放參數，這些參數可以使用file命令獲得
	*/

#define Sample_Size 16
#define Sample_Rate 44100

int play_sound(char *filename)
{
	struct stat stat_buf;
	unsigned char *buf = NULL;
	int handler,fd;
	int result;
	int arg,status;
	//打開聲音文件，將文件讀入內存
	fd = open(filename,O_RDONLY);
	if(fd < 0)
		return -1;
	if(fstat(fd,&stat_buf))
	{
		close(fd);
		return -1;
	}
	if(!stat_buf.st_size)
	{
		close(fd);
		return -1;
	}

	buf = malloc(stat_buf.st_size);
	if(!buf)
	{
		close(fd);
		return -1;
	}
	if(read(fd,buf,stat_buf.st_size) < 0)
	{
		free(buf);
		close(fd);
		return -1;
	}

	/*
	打開聲卡設備，并設置聲卡播放參數，這些參數必須與聲音文件參數一致
	*/

	handler = open(Audio_Device,O_WRONLY);
	if(handler == -1)
	{
		perror("Cannot open the Audio_Device");
		return -1;
	}

	arg = Sample_Rate;
	status = ioctl(handler,SOUND_PCM_WRITE_RATE,&arg);
	if(status == -1)
	{
		perror("error from SOUND_PCM_WRITE_RATE ioctl");
		return -1;
	}

	arg = Sample_Size;
	status = ioctl(handler,SOUND_PCM_WRITE_BITS,&arg);
	if(status == -1)
	{
		perror("error from SOUND_PCM_WRITE_BITS ioctl");
		return -1;
	}

	result = write(handler,buf,stat_buf.st_size);
	if(result == -1)
	{
		perror("Fail to play the sound");
		return -1;
	}
	free(buf);
	close(fd);
	close(handler);
	return result;
}

void main(void)
{
	play_sound("windowXp.wav");
}