shithub: riscv

ref: 0b8851ddb688e8de813196b7cd62f113edde2e3a
dir: /sys/src/games/music/playlistfs/player.c/

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#include <u.h>
#include <libc.h>
#include <thread.h>
#include <fcall.h>
#include "pool.h"
#include "playlist.h"

typedef struct Playfd Playfd;

struct Playfd {
	/* Describes a file to play for starting up pac4dec/mp3,... */
	char	*filename;	/* mallocated */
	int	fd;		/* filedesc to use */
	int	cfd;		/* fildesc to close */
};

Channel *full, *empty, *playout, *spare;
Channel	*playc, *pacc;

ulong totbytes, totbuffers;

static char curfile[8192];

void
decexec(void *a)
{
	char buf[256];
	Playfd *pfd;
	Pacbuf *pb;

	threadsetname("decexec");
	pfd = a;
	close(pfd->cfd);	/* read fd */
	if(pfd->fd != 1){
		dup(pfd->fd, 1);
		close(pfd->fd);
	}
	close(0); open("/dev/null", OREAD);
	close(2); open("/dev/null", OWRITE);
	strncpy(buf, pfd->filename, sizeof(buf)-1);
	buf[sizeof(buf)-1] = 0;
	free(pfd->filename);
	free(pfd);
	procexecl(nil, "/bin/play", "play", "-o", "/fd/1", buf, nil);
	if((pb = nbrecvp(spare)) == nil)
		pb = malloc(sizeof(Pacbuf));
	pb->cmd = Error;
	pb->off = 0;
	pb->len = snprint(pb->data, sizeof(pb->data), "startplay: exec play failed");
	sendp(full, pb);
	threadexits("exec");
}

static int
startplay(ushort n)
{
	int fd[2];
	Playfd *pfd;
	char *file;

	file = getplaylist(n);
	if(file == nil)
		return Undef;
	if (debug & DbgPlayer)
		fprint(2, "startplay: file is `%s'\n", file);
	if(pipe(fd) < 0)
		sysfatal("pipe: %r");
	pfd = malloc(sizeof(Playfd));
	pfd->filename = file;	/* mallocated already */
	pfd->fd = fd[1];
	pfd->cfd = fd[0];
	procrfork(decexec, pfd, 4096, RFFDG|RFENVG);
	close(fd[1]);	/* write fd, for pac4dec */
	return fd[0];	/* read fd */
}

static void
rtsched(void)
{
	int fd;
	char *ctl;

	ctl = smprint("/proc/%ud/ctl", getpid());
	if((fd = open(ctl, ORDWR)) < 0) 
		sysfatal("%s: %r", ctl);
	if(fprint(fd, "period 20ms") < 0)
		sysfatal("%s: %r", ctl);
	if(fprint(fd, "cost 100µs") < 0)
		sysfatal("%s: %r", ctl);
	if(fprint(fd, "sporadic") < 0)
		sysfatal("%s: %r", ctl);
	if(fprint(fd, "admit") < 0)
		sysfatal("%s: %r", ctl);
	close(fd);
	free(ctl);
}

static void
boost(void)
{
	int fd;
	char *ctl;

	ctl = smprint("/proc/%ud/ctl", getpid());
	if((fd = open(ctl, ORDWR)) >= 0) {
		fprint(fd, "pri 13");
		close(fd);
	}
	free(ctl);
}

void
decproc(void*)
{
	Pmsg playstate, newstate;
	int fd;
	Pacbuf *pb;
	Alt a[3] = {
		{empty, &pb, CHANNOP},
		{playc, &newstate.m, CHANRCV},
		{nil, nil, CHANEND},
	};

	threadsetname("decproc");
	close(srvfd[1]);
	newstate.cmd = playstate.cmd = Stop;
	newstate.off = playstate.off = 0;
	fd = -1;
	for(;;){
		switch(alt(a)){
		case 0:
			/* Play out next buffer (pb points to one already) */
			assert(fd >= 0);	/* Because we must be in Play mode */
			pb->m = playstate.m;
			pb->len = read(fd, pb->data, sizeof pb->data);
			if(pb->len > 0){
				sendp(full, pb);
				break;
			}
			if(pb->len < 0){
				if(debug & DbgPlayer)
					fprint(2, "pac, error: %d\n", playstate.off);
				pb->cmd = Error;
				pb->len = snprint(pb->data, sizeof pb->data, "%s: %r", curfile);
				sendp(full, pb);
			}else{
				/* Simple end of file */
				sendp(empty, pb); /* Don't need buffer after all */
			}
			close(fd);
			fd = -1;
			if(debug & DbgPlayer)
				fprint(2, "pac, eof: %d\n", playstate.off);
			/* End of file, do next by falling through */
			newstate.cmd = playstate.cmd;
			newstate.off = playstate.off + 1;
		case 1:
			if((debug & DbgPac) && newstate.cmd)
				fprint(2, "Pacproc: newstate %s-%d, playstate %s-%d\n",
					statetxt[newstate.cmd], newstate.off,
					statetxt[playstate.cmd], playstate.off);
			/* Deal with an incoming command */
			if(newstate.cmd == Pause || newstate.cmd == Resume){
				/* Just pass them on, don't change local state */
				pb = recvp(spare);
				pb->m = newstate.m;
				sendp(full, pb);
				break;
			}
			/* Stop whatever we're doing */
			if(fd >= 0){
				if(debug & DbgPlayer)
					fprint(2, "pac, stop\n");
				/* Stop any active (pac) decoders */
				close(fd);
				fd = -1;
			}
			a[0].op = CHANNOP;
			switch(newstate.cmd){
			default:
				sysfatal("decproc: unexpected newstate %d", newstate.cmd);
			case Stop:
				/* Wait for state to change */
				break;
			case Skip:
			case Play:
				fd = startplay(newstate.off);
				if(fd >=0){
					playstate = newstate;
					a[0].op = CHANRCV;
					continue;	/* Start reading */
				}
				newstate.cmd = Stop;
			}
			pb = recvp(spare);
			pb->m = newstate.m;
			sendp(full, pb);
			playstate = newstate;
		}
	}
}

void
pcmproc(void*)
{
	Pmsg localstate, newstate, prevstate;
	int fd, n;
	Pacbuf *pb, *b;
	Alt a[3] = {
		{full, &pb, CHANRCV},
		{playout, &pb, CHANRCV},
		{nil, nil, CHANEND},
	};

	/*
	 * This is the real-time proc.
	 * It gets its input from two sources, full data/control buffers from the decproc
	 * which mixes decoded data with control messages, and data buffers from the pcmproc's
	 * (*this* proc's) own internal playout buffer.
	 * When a command is received on the `full' channel containing a command that warrants
	 * an immediate change of audio source (e.g., to silence or to another number), we just
	 * toss everything in the pipeline -- i.e., the playout channel
	 * Finally, we report all state changes using `playupdate' (another message channel)
	 */
	threadsetname("pcmproc");
	close(srvfd[1]);
	fd = -1;
	localstate.cmd = 0;	/* Force initial playupdate */
	newstate.cmd = Stop;
	newstate.off = 0;
//	rtsched();
	boost();
	for(;;){
		if(newstate.m != localstate.m){
			playupdate(newstate, nil);
			localstate = newstate;
		}
		switch(alt(a)){
		case 0:
			/* buffer received from decproc */
			if((debug & DbgPcm) && localstate.m != prevstate.m){
				fprint(2, "pcm, full: %s-%d, local state is %s-%d\n",
					statetxt[pb->cmd], pb->off,
					statetxt[localstate.cmd], localstate.off);
				prevstate.m = localstate.m;
			}
			switch(pb->cmd){
			default:
				sysfatal("pcmproc: unknown newstate: %s-%d", statetxt[pb->cmd], pb->off);
			case Resume:
				a[1].op = CHANRCV;
				newstate.cmd = Play;
				break;
			case Pause:
				a[1].op = CHANNOP;
				newstate.cmd = Pause;
				if(fd >= 0){
					close(fd);
					fd = -1;
				}
				break;
			case Stop:
				/* Dump all data in the buffer */
				while(b = nbrecvp(playout))
					if(b->cmd == Error){
						playupdate(b->Pmsg, b->data);
						sendp(spare, b);
					}else
						sendp(empty, b);
				newstate.m = pb->m;
				a[1].op = CHANRCV;
				if(fd >= 0){
					close(fd);
					fd = -1;
				}
				break;
			case Skip:
				/* Dump all data in the buffer, then fall through */
				while(b = nbrecvp(playout))
					if(b->cmd == Error){
						playupdate(pb->Pmsg, pb->data);
						sendp(spare, pb);
					}else
						sendp(empty, b);
				a[1].op = CHANRCV;
				newstate.cmd = Play;
			case Error:
			case Play:
				/* deal with at playout, just requeue */
				sendp(playout, pb);
				pb = nil;
				localstate = newstate;
				break;
			}
			/* If we still have a buffer, free it */
			if(pb)
				sendp(spare, pb);
			break;
		case 1:
			/* internal buffer */
			if((debug & DbgPlayer) && localstate.m != prevstate.m){
				fprint(2, "pcm, playout: %s-%d, local state is %s-%d\n",
					statetxt[pb->cmd], pb->off,
					statetxt[localstate.cmd], localstate.off);
				prevstate.m = localstate.m;
			}
			switch(pb->cmd){
			default:
				sysfatal("pcmproc: unknown newstate: %s-%d", statetxt[pb->cmd], pb->off);
			case Error:
				playupdate(pb->Pmsg, pb->data);
				localstate = newstate;
				sendp(spare, pb);
				break;
			case Play:
				if(fd < 0 && (fd = open("/dev/audio", OWRITE)) < 0){
					a[1].op = CHANNOP;
					newstate.cmd = Pause;
					pb->cmd = Error;
					snprint(pb->data, sizeof(pb->data),
						"/dev/audio: %r");
					playupdate(pb->Pmsg, pb->data);
					sendp(empty, pb);
					break;
				}
				/* play out this buffer */
				totbytes += pb->len;
				totbuffers++;
				n = write(fd, pb->data, pb->len);
				if (n != pb->len){
					if (debug & DbgPlayer)
						fprint(2, "pcmproc: file %d: %r\n", pb->off);
					if (n < 0)
						sysfatal("pcmproc: write: %r");
				}
				newstate.m = pb->m;
				sendp(empty, pb);
				break;
			}
			break;
		}
	}
}

void
playinit(void)
{
	int i;

	full = chancreate(sizeof(Pacbuf*), 1);
	empty = chancreate(sizeof(Pacbuf*), NPacbuf);
	spare = chancreate(sizeof(Pacbuf*), NSparebuf);
	playout = chancreate(sizeof(Pacbuf*), NPacbuf+NSparebuf);
	for(i = 0; i < NPacbuf; i++)
		sendp(empty, malloc(sizeof(Pacbuf)));
	for(i = 0; i < NSparebuf; i++)
		sendp(spare, malloc(sizeof(Pacbuf)));

	playc = chancreate(sizeof(Pmsg), 1);
	procrfork(decproc, nil, 32*1024, RFFDG);
	procrfork(pcmproc, nil, 32*1024, RFFDG);
}

char *
getplaystat(char *p, char *e)
{
	p = seprint(p, e, "empty buffers %d of %d\n", empty->n, empty->s);
	p = seprint(p, e, "full buffers %d of %d\n", full->n, full->s);
	p = seprint(p, e, "playout buffers %d of %d\n", playout->n, playout->s);
	p = seprint(p, e, "spare buffers %d of %d\n", spare->n, spare->s);
	p = seprint(p, e, "bytes %lud / buffers %lud played\n", totbytes, totbuffers);
	return p;
}