#include <stdlib.h>#include <stdio.h>#include <dpmi.h>#include <go32.h>#include <sys/farptr.h>#include <sys/movedata.h>#include "defs.h"#include "pcm.h"#include "rc.h"struct pcm pcm;static int ver;static int dmaaddr;extern volatile int sb_ready;extern volatile int sb_frag;static int samplerate = 44100;static int sound = 1;rcvar_t pcm_exports[] ={	RCV_BOOL("sound", &sound),	RCV_INT("samplerate", &samplerate),	RCV_END};void pcm_init(){	int i;	char *blaster, *s;	int addr, irq, dma;	int dmaseg, dmasel;		ver = -1;	if ((blaster = getenv("BLASTER")))	{		for (s = blaster; *s; s++)		{			switch (*s)			{			case 'A':				addr = strtol(s+1, 0, 16);				break;			case 'I':				irq = atoi(s+1);				break;			case 'D':				dma = atoi(s+1);				break;			}		}		if ((addr & 0xff0) != addr || addr < 0x200 || addr >= 0x300)			die("invalid sb base address: %03X\n", addr);		if (irq <= 0 || irq > 15)			die ("invalid sb irq: %d\n", irq);		if (dma < 0 || dma > 3)			die ("invalid sb dma channel: %d\n", dma);		ver = sb_init(addr, irq, dma);	}	if (ver < 0)	{		pcm.hz = 11025;		pcm.len = 11025;		pcm.buf = malloc(pcm.len);		pcm.pos = 0;		return;	}	pcm.len = pcm.hz / 60;	for (i = 1; i < pcm.len; i<<=1);	pcm.len = i;	/* Get page-aligned dos memory for dma buffer */	dmaseg = __dpmi_allocate_dos_memory((pcm.len+7)>>3, &dmasel);	if (dmaseg < 0)		die("failed to allocate low memory for sb dma\n");	dmaaddr = dmaseg << 4;	if ((dmaaddr & 0xffff) + pcm.len > 0x10000)		dmaaddr = (dmaaddr & 0x10000) + 0x10000;}void pcm_close(){}int pcm_submit(){	byte *buf;		if (ver < 0) return 0;	if (pcm.pos < pcm.len) return 1;	while (!sb_ready);	_dosmemputl(pcm.buf, pcm.len >> 2, dmaaddr);	pcm.pos = 0;	return 1;}