#include <u.h>#include <libc.h>#include <stdio.h>#include <thread.h>#include "dat.h"#include "fns.h" static cvar_t *sndbits;static cvar_t *sndspeed;static cvar_t *sndchannels;static cvar_t *snddev; static int afd = -1, wpos;enum{	Nbuf = 4,};static Channel *schan;static QLock sndlock; static voidsproc(void *){	int n; 	for(;;){		if(recv(schan, nil) < 0)			break;		if((n = write(afd, dma.buffer, Nsbuf)) != Nsbuf)			break;		qlock(&sndlock);		wpos += n;		qunlock(&sndlock);	}} intSNDDMA_GetDMAPos(void){	if(afd < 0)		return 0;	qlock(&sndlock);	dma.samplepos = wpos / Sampsz;	qunlock(&sndlock);	return dma.samplepos;} voidSNDDMA_Submit(void){	if(nbsend(schan, nil) < 0){		fprint(2, "SNDDMA_Submit: %r\n");		shutsnd();	}} voidshutsnd(void){	if(afd < 0)		return;	afd = -1;	close(afd);	chanfree(schan);	sound_started = 0;	num_sfx = 0;} voidrestartsnd(void){	sfx_t *s; 	if(afd < 0)		return;	for(s=known_sfx+num_sfx; s<known_sfx+num_sfx*2; s++){		if(!s->name[0])			continue;		if(s->cache)			Z_Free(s->cache);		memset(s, 0, sizeof *s);	}	num_sfx = 0;	soundtime = 0;	paintedtime = 0;	S_StopAllSounds();	wpos = 0;	CL_RegisterSounds();} voidinitsnd(void){	if((afd = open("/dev/audio", OWRITE)) < 0){		fprint(2, "initsnd %r\n");		return;	}	dma.samplebits = Sampsz * 8;	dma.speed = Rate;	dma.channels = 2;	dma.samples = Nsamp;	dma.submission_chunk = 1;	dma.buffer = emalloc(Nsamp * Sampsz);	dma.samplepos = 0;	wpos = 0;	schan = chancreate(sizeof(int), Nbuf);	if(proccreate(sproc, nil, 8192) < 0)		sysfatal("proccreate: %r\n");	s_volume = Cvar_Get("s_volume", "0.7", CVAR_ARCHIVE);	s_khz = Cvar_Get("s_khz", "22", CVAR_ARCHIVE);	s_loadas8bit = Cvar_Get("s_loadas8bit", "0", CVAR_ARCHIVE);	s_mixahead = Cvar_Get("s_mixahead", "0.2", CVAR_ARCHIVE);	S_InitScaletable();	sound_started = 1;	num_sfx = 0;	soundtime = 0;	paintedtime = 0;	S_StopAllSounds();}