output_solaris.c

杜比AC-3编码解码器（参考程序）

/*
 *
 *  output_solaris.c
 *
 *	Copyright (C) Aaron Holtzman - May 1999
 *
 *  This file is part of ac3dec, a free Dolby AC-3 stream decoder.
 *	
 *  ac3dec 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; either version 2, or (at your option)
 *  any later version.
 *   
 *  ac3dec 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 for more details.
 *   
 *  You should have received a copy of the GNU General Public License
 *  along with GNU Make; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 
 *
 *
 */

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/audioio.h>
#include <sys/ioctl.h>
#include <stropts.h>
#include <signal.h>
#include <math.h>

//FIXME broken solaris headers!
int usleep(unsigned int useconds);


//this sux...types should go in config.h methinks
typedef signed short sint_16;
typedef unsigned int uint_32;

#include "output.h"

/* Global to keep track of old state */
static audio_info_t info;
static char dev[] = "/dev/audio";
static int fd;


/*
 * open the audio device for writing to
 */
int output_open(int bits, int rate, int channels)
{

  /*
   * Open the device driver
   */

	fd=open(dev,O_WRONLY);
  if(fd < 0) 
  {
    fprintf(stderr,"%s: Opening audio device %s\n",
        strerror(errno), dev);
    goto ERR;
  }
	fprintf(stderr,"Opened audio device \"%s\"\n",dev);

	/* Setup our parameters */
	AUDIO_INITINFO(&info);

	info.play.sample_rate = rate;
	info.play.precision = bits;
	info.play.channels = channels;
	info.play.buffer_size = 1024;
	info.play.encoding = AUDIO_ENCODING_LINEAR;
	//info.play.port = AUDIO_SPEAKER;
	//info.play.gain = 110;

	/* Write our configuration */
	/* An implicit GETINFO is also performed so we can get
	 * the buffer_size */

  if(ioctl(fd, AUDIO_SETINFO, &info) < 0)
  {
    fprintf(stderr, "%s: Writing audio config block\n",strerror(errno));
    goto ERR;
  }

	return 1;

ERR:
  if(fd >= 0) { close(fd); }
  return 0;
}

unsigned long j= 0 ;
/*
 * play the sample to the already opened file descriptor
 */
void output_play(sint_16* output_samples, uint_32 num_bytes)
{
	write(fd,&output_samples[0 * 512],1024);
	write(fd,&output_samples[1 * 512],1024);
	write(fd,&output_samples[2 * 512],1024);
	write(fd,&output_samples[3 * 512],1024);
	write(fd,&output_samples[4 * 512],1024);
	write(fd,&output_samples[5 * 512],1024);
}


void
output_close(void)
{
	close(fd);
}