Source to src/sd-file/sound.c

 /*
  * UAE - The Un*x Amiga Emulator
  *
  * Support for Linux/USS sound
  *
  * Copyright 1997 Bernd Schmidt
  */

#include "sysconfig.h"
#include "sysdeps.h"

#include "options.h"
#include "memory.h"
#include "custom.h"
#include "audio.h"
#include "gensound.h"
#include "sounddep/sound.h"

#include <sys/ioctl.h>
#include <sys/soundcard.h>

int sound_fd;
static int have_sound;
static unsigned long formats;

unsigned long sndbuf_written;

uae_u16 sndbuffer[44100];
uae_u16 *sndbufpt;
int sndbufsize;

static int exact_log2(int v)
{
    int l = 0;
    while ((v >>= 1) != 0)
	l++;
    return l;
}

void close_sound(void)
{
    int t;
    uae_u32 v;
    char buf[4];

    if (!have_sound)
	return;

    t = 0;
    v = sndbuf_written;
    buf[t] = v & 255;
    buf[t+1] = (v>>8) & 255;
    buf[t+2] = (v>>16) & 255;
    buf[t+3] = (v>>24) & 255;
    lseek (sound_fd, 40, SEEK_SET);
    write (sound_fd, buf, 4);

    v += 36;
    buf[t] = v & 255;
    buf[t+1] = (v>>8) & 255;
    buf[t+2] = (v>>16) & 255;
    buf[t+3] = (v>>24) & 255;
    lseek (sound_fd, 4, SEEK_SET);
    write (sound_fd, buf, 4);

    close(sound_fd);
}

int setup_sound(void)
{
    sound_fd = open ("sound.output", O_CREAT|O_TRUNC|O_WRONLY, 0666);
    have_sound = !(sound_fd < 0);
    if (!have_sound)
	return 0;

    sound_available = 1;
    return 1;
}

int init_sound (void)
{
    int t;
    uae_u32 v;
    int tmp;

    char buf[200] = "RIFF    WAVEfmt                     data    ";

    /* Prepare a .WAV header */
    sndbuf_written = 44;
    t = 16; v = 16;
    buf[t] = v & 255;
    buf[t+1] = (v>>8) & 255;
    buf[t+2] = (v>>16) & 255;
    buf[t+3] = (v>>24) & 255;

    t = 20; v = 0x00010001 + (/* currprefs.stereo */ 1 ? 0x10000 : 0);
    buf[t] = v & 255;
    buf[t+1] = (v>>8) & 255;
    buf[t+2] = (v>>16) & 255;
    buf[t+3] = (v>>24) & 255;

    t = 24; v = currprefs.sound_freq;
    buf[t] = v & 255;
    buf[t+1] = (v>>8) & 255;
    buf[t+2] = (v>>16) & 255;
    buf[t+3] = (v>>24) & 255;
    t = 32; v = (2 * 2) + 65536 * 16;
    buf[t] = v & 255;
    buf[t+1] = (v>>8) & 255;
    buf[t+2] = (v>>16) & 255;
    buf[t+3] = (v>>24) & 255;
    t = 28; v = (currprefs.sound_freq * 2 * 2);
    buf[t] = v & 255;
    buf[t+1] = (v>>8) & 255;
    buf[t+2] = (v>>16) & 255;
    buf[t+3] = (v>>24) & 255;
    write (sound_fd, buf, 44);

    obtained_freq = currprefs.sound_freq;

    init_sound_table16 ();
    sample_handler = sample16s_handler;
    sound_available = 1;
    sndbufsize = 44100;
    printf ("Writing sound into \"sound.output\"; 16 bits at %d Hz\n",
	    currprefs.sound_freq, sndbufsize);
    sndbufpt = sndbuffer;
    return 1;
}