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audio/mixfs: implement Tstat to obtain buffer size, better underrun handling

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This commit is contained in:
cinap_lenrek 2013-12-27 20:39:56 +01:00
parent 9c4ca0a51c
commit 7d9ae4883d
1 changed files with 51 additions and 13 deletions
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64
sys/src/cmd/audio/mixfs/mixfs.c
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@ -8,6 +8,7 @@ enum {
NBUF = 8*1024, NBUF = 8*1024,
NDELAY = 2048, NDELAY = 2048,
NCHAN = 2, NCHAN = 2,
FREQ = 44100,
}; };
typedef struct Stream Stream; typedef struct Stream Stream;
@ -83,21 +84,21 @@ void
audioproc(void *) audioproc(void *)
{ {
static uchar buf[NBUF*NCHAN*2]; static uchar buf[NBUF*NCHAN*2];
int nsleep, fd, i, j, n, m, v; int sweep, fd, i, j, n, m, v;
Stream *s; Stream *s;
uchar *p; uchar *p;
threadsetname("audioproc"); threadsetname("audioproc");
fd = -1; fd = -1;
nsleep = 0; sweep = 0;
for(;;){ for(;;){
m = NBUF; m = NBUF;
for(s = streams; s < streams+nelem(streams); s++){ for(s = streams; s < streams+nelem(streams); s++){
qlock(s); qlock(s);
if(s->run){ if(s->run){
n = (long)(s->wp - mixrp); n = (long)(s->wp - mixrp);
if(n <= 0 && nsleep > 4) if(n <= 0 && (s->used == 0 || sweep))
s->run = 0; s->run = 0;
else if(n < m) else if(n < m)
m = n; m = n;
@ -109,20 +110,34 @@ audioproc(void *)
m %= NBUF; m %= NBUF;
if(m == 0){ if(m == 0){
sleep(1<<nsleep); int ms;
if(nsleep < 7)
nsleep++; ms = 100;
else { if(fd >= 0){
close(fd); if(sweep){
fd = -1; close(fd);
fd = -1;
} else {
/* attempt to sleep just shortly before buffer underrun */
ms = seek(fd, 0, 2);
if(ms > 0){
ms *= 800;
ms /= FREQ*NCHAN*2;
} else
ms = 4;
}
sweep = 1;
} }
sleep(ms);
continue; continue;
} }
sweep = 0;
if(fd < 0) if(fd < 0)
if((fd = open("/dev/audio", OWRITE)) < 0) if((fd = open("/dev/audio", OWRITE)) < 0){
continue; fprint(2, "%s: open /dev/audio: %r\n", argv0);
sleep(1000);
nsleep = 0; continue;
}
p = buf; p = buf;
for(i=0; i<m; i++){ for(i=0; i<m; i++){
@ -179,6 +194,28 @@ fswrite(Req *r)
srvacquire(srv); srvacquire(srv);
} }
void
fsstat(Req *r)
{
Stream *s;
if(r->fid->file == nil){
respond(r, "bug");
return;
}
if(strcmp(r->fid->file->name, "audio") == 0 && (s = r->fid->aux) != nil){
qlock(s);
if(s->run){
r->d.length = (long)(s->wp - mixrp);
r->d.length *= NCHAN*2;
} else {
r->d.length = 0;
}
qunlock(s);
}
respond(r, nil);
}
void void
fsstart(Srv *) fsstart(Srv *)
{ {
@ -200,6 +237,7 @@ fsend(Srv *)
Srv fs = { Srv fs = {
.open= fsopen, .open= fsopen,
.write= fswrite, .write= fswrite,
.stat= fsstat,
.destroyfid= fsclunk, .destroyfid= fsclunk,
.start= fsstart, .start= fsstart,
.end= fsend, .end= fsend,