mirror of
				https://github.com/alsa-project/alsa-lib.git
				synced 2025-10-29 05:40:25 -04:00 
			
		
		
		
	
		
			
				
	
	
		
			265 lines
		
	
	
	
		
			7.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			265 lines
		
	
	
	
		
			7.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
 | |
| #ifdef USE_PCM
 | |
| /*
 | |
|  *  PCM timer layer
 | |
|  */
 | |
| 
 | |
| int pcard = 0;
 | |
| int pdevice = 0;
 | |
| int pfragment_size = 4096;
 | |
| 
 | |
| void set_format(snd_pcm_t *phandle)
 | |
| {
 | |
| 	int err;
 | |
| 	snd_pcm_format_t format;
 | |
| 
 | |
| 	bzero(&format, sizeof(format));
 | |
| 	format.format = SND_PCM_SFMT_S16_LE;
 | |
| 	format.channels = 2;
 | |
| 	format.rate = 44100;
 | |
| 	if ((err = snd_pcm_playback_format(phandle, &format)) < 0) {
 | |
| 		fprintf(stderr, "Playback format error: %s\n", snd_strerror(err));
 | |
| 		exit(0);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| void set_fragment(snd_pcm_t *phandle)
 | |
| {
 | |
| 	int err;
 | |
| 	snd_pcm_playback_params_t pparams;
 | |
| 
 | |
| 	bzero(&pparams, sizeof(pparams));
 | |
| 	pparams.fragment_size = pfragment_size;
 | |
| 	pparams.fragments_max = -1;	/* maximum */
 | |
| 	pparams.fragments_room = 1;
 | |
| 	if ((err = snd_pcm_playback_params(phandle, &pparams)) < 0) {
 | |
| 		fprintf(stderr, "Fragment setup error: %s\n", snd_strerror(err));
 | |
| 		exit(0);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| void show_playback_status(snd_pcm_t *phandle)
 | |
| {
 | |
| 	int err;
 | |
| 	snd_pcm_playback_status_t pstatus;
 | |
| 
 | |
| 	if ((err = snd_pcm_playback_status(phandle, &pstatus)) < 0) {
 | |
| 		fprintf(stderr, "Playback status error: %s\n", snd_strerror(err));
 | |
| 		exit(0);
 | |
| 	}
 | |
| 	printf("Playback status\n");
 | |
| 	printf("    Real rate      : %u\n", pstatus.rate);
 | |
| 	printf("    Fragments      : %i\n", pstatus.fragments);
 | |
| 	printf("    Fragment size  : %i\n", pstatus.fragment_size);
 | |
| }
 | |
| #endif
 | |
| /*
 | |
|  *  Simple event sender
 | |
|  */
 | |
| 
 | |
| void event_sender_start_timer(snd_seq_t *handle, int client, int queue, snd_pcm_t *phandle)
 | |
| {
 | |
| 	int err;
 | |
| 	
 | |
| #ifdef USE_PCM
 | |
| 	if (phandle) {
 | |
| 		snd_pcm_playback_info_t pinfo;
 | |
| 		snd_seq_queue_timer_t qtimer;
 | |
| 
 | |
| 		if ((err = snd_pcm_playback_info(phandle, &pinfo)) < 0) {
 | |
| 			fprintf(stderr, "Playback info error: %s\n", snd_strerror(err));
 | |
| 			exit(0);
 | |
| 		}
 | |
| 		bzero(&qtimer, sizeof(qtimer));
 | |
| 		qtimer.type = SND_SEQ_TIMER_MASTER;
 | |
| 		/* note: last bit from subdevices specifies playback */
 | |
| 		/* or capture direction for the timer specification */
 | |
| 		qtimer.number = SND_TIMER_PCM(pcard, pdevice, pinfo.subdevice << 1);
 | |
| 		if ((err = snd_seq_set_queue_timer(handle, queue, &qtimer)) < 0) {
 | |
| 			fprintf(stderr, "Sequencer PCM timer setup failed: %s\n", snd_strerror(err));
 | |
| 			exit(0);
 | |
| 		}
 | |
| 	}	
 | |
| #endif
 | |
| 	if ((err = snd_seq_start_queue(handle, queue, NULL))<0)
 | |
| 		fprintf(stderr, "Timer event output error: %s\n", snd_strerror(err));
 | |
| 	snd_seq_flush_output(handle);
 | |
| }
 | |
| 
 | |
| void event_sender_filter(snd_seq_t *handle)
 | |
| {
 | |
| 	int err;
 | |
| 	snd_seq_client_info_t info;
 | |
| 
 | |
| 	if ((err = snd_seq_get_client_info(handle, &info)) < 0) {
 | |
| 		fprintf(stderr, "Unable to get client info: %s\n", snd_strerror(err));
 | |
| 		return;
 | |
| 	}
 | |
| 	info.filter = SND_SEQ_FILTER_USE_EVENT;
 | |
| 	memset(&info.event_filter, 0, sizeof(info.event_filter));
 | |
| 	snd_seq_set_bit(SND_SEQ_EVENT_ECHO, info.event_filter);
 | |
| 	if ((err = snd_seq_set_client_info(handle, &info)) < 0) {
 | |
| 		fprintf(stderr, "Unable to set client info: %s\n", snd_strerror(err));
 | |
| 		return;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| void send_event(snd_seq_t *handle, int queue, int client, int port,
 | |
|                 snd_seq_port_subscribe_t *sub, int *time)
 | |
| {
 | |
| 	int err;
 | |
| 	snd_seq_event_t ev;
 | |
| 	
 | |
| 	bzero(&ev, sizeof(ev));
 | |
| 	ev.queue = queue;
 | |
| 	ev.source.client = ev.dest.client = client;
 | |
| 	ev.source.port = ev.dest.port = port;
 | |
| 	ev.flags = SND_SEQ_TIME_STAMP_REAL | SND_SEQ_TIME_MODE_ABS;
 | |
| 	ev.time.time.tv_sec = *time; (*time)++;
 | |
| 	ev.type = SND_SEQ_EVENT_ECHO;
 | |
| 	if ((err = snd_seq_event_output(handle, &ev))<0)
 | |
| 		fprintf(stderr, "Event output error: %s\n", snd_strerror(err));
 | |
| 	ev.dest.client = sub->dest.client;
 | |
| 	ev.dest.port = sub->dest.port;
 | |
| 	ev.type = SND_SEQ_EVENT_PGMCHANGE;
 | |
| 	ev.data.control.channel = 0;
 | |
| 	ev.data.control.value = 16;
 | |
| 	if ((err = snd_seq_event_output(handle, &ev))<0)
 | |
| 		fprintf(stderr, "Event output error: %s\n", snd_strerror(err));
 | |
| 	ev.type = SND_SEQ_EVENT_NOTE;
 | |
| 	ev.data.note.channel = 0;
 | |
| 	ev.data.note.note = 64 + (queue*2);
 | |
| 	ev.data.note.velocity = 127;
 | |
| 	ev.data.note.off_velocity = 127;
 | |
| 	ev.data.note.duration = 500;	/* 0.5sec */
 | |
| 	if ((err = snd_seq_event_output(handle, &ev))<0)
 | |
| 		fprintf(stderr, "Event output error: %s\n", snd_strerror(err));
 | |
| 	if ((err = snd_seq_flush_output(handle))<0)
 | |
| 		fprintf(stderr, "Event flush error: %s\n", snd_strerror(err));
 | |
| }
 | |
| 
 | |
| void event_sender(snd_seq_t *handle, int argc, char *argv[])
 | |
| {
 | |
| 	snd_seq_event_t *ev;
 | |
| 	snd_seq_port_info_t port;
 | |
| 	snd_seq_port_subscribe_t sub;
 | |
| 	fd_set out, in;
 | |
| 	int client, queue, max, err, v1, v2, time = 0, pcm_flag = 0;
 | |
| 	char *ptr;
 | |
| 	snd_pcm_t *phandle = NULL;
 | |
| 
 | |
| 	if (argc < 1) {
 | |
| 		fprintf(stderr, "Invalid destination...\n");
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	if ((client = snd_seq_client_id(handle))<0) {
 | |
| 		fprintf(stderr, "Cannot determine client number: %s\n", snd_strerror(client));
 | |
| 		return;
 | |
| 	}
 | |
| 	printf("Client ID = %i\n", client);
 | |
| 	if ((queue = snd_seq_alloc_queue(handle))<0) {
 | |
| 		fprintf(stderr, "Cannot allocate queue: %s\n", snd_strerror(queue));
 | |
| 		return;
 | |
| 	}
 | |
| 	printf("Queue ID = %i\n", queue);
 | |
| 	event_sender_filter(handle);
 | |
| 	if ((err = snd_seq_block_mode(handle, 0))<0)
 | |
| 		fprintf(stderr, "Cannot set nonblock mode: %s\n", snd_strerror(err));
 | |
| 	bzero(&port, sizeof(port));
 | |
| 	port.capability = SND_SEQ_PORT_CAP_WRITE | SND_SEQ_PORT_CAP_READ;
 | |
| 	strcpy(port.name, "Output");
 | |
| 	if ((err = snd_seq_create_port(handle, &port)) < 0) {
 | |
| 		fprintf(stderr, "Cannot create output port: %s\n", snd_strerror(err));
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	bzero(&sub, sizeof(sub));
 | |
| 	sub.sender.client = client;
 | |
| 	sub.sender.port = port.port;
 | |
| 	sub.exclusive = 0;
 | |
| 
 | |
| 	for (max = 0; max < argc; max++) {
 | |
| 		ptr = argv[max];
 | |
| 		if (!ptr)
 | |
| 			continue;
 | |
| 		if (!strcmp(ptr, "pcm")) {
 | |
| 			pcm_flag = 1;
 | |
| 			continue;
 | |
| 		}
 | |
| 		if (sscanf(ptr, "%i.%i", &v1, &v2) != 2) {
 | |
| 			fprintf(stderr, "Wrong argument '%s'...\n", argv[max]);
 | |
| 			return;
 | |
| 		}
 | |
| 		sub.dest.client = v1;
 | |
| 		sub.dest.port = v2;
 | |
| 		if ((err = snd_seq_subscribe_port(handle, &sub))<0) {
 | |
| 			fprintf(stderr, "Cannot subscribe port %i from client %i: %s\n", v2, v1, snd_strerror(err));
 | |
| 			return;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	printf("Destination client = %i, port = %i\n", sub.dest.client, sub.dest.port);
 | |
| 
 | |
| #ifdef USE_PCM
 | |
| 	if (pcm_flag) {
 | |
| 		if ((err = snd_pcm_open(&phandle, pcard, pdevice, SND_PCM_OPEN_PLAYBACK)) < 0) {
 | |
| 			fprintf(stderr, "Playback open error: %s\n", snd_strerror(err));
 | |
| 			exit(0);
 | |
| 		}
 | |
| 		set_format(phandle);
 | |
| 		set_fragment(phandle);	
 | |
| 		show_playback_status(phandle);
 | |
| 		pbuf = calloc(1, pfragment_size);
 | |
| 		if (pbuf == NULL) {
 | |
| 			fprintf(stderr, "No enough memory...\n");
 | |
| 			exit(0);
 | |
| 		}
 | |
| 	}
 | |
| #endif
 | |
| 	event_sender_start_timer(handle, client, queue, phandle);
 | |
| 	
 | |
| 	/* send the first event */
 | |
| 	send_event(handle, queue, client, port.port, &sub, &time);
 | |
| 
 | |
| 	while (1) {
 | |
| 		FD_ZERO(&out);
 | |
| 		FD_ZERO(&in);
 | |
| 		max = snd_seq_file_descriptor(handle);
 | |
| 		FD_SET(snd_seq_file_descriptor(handle), &in);
 | |
| 		if (snd_seq_event_output_pending(handle)) {
 | |
| 			FD_SET(snd_seq_file_descriptor(handle), &out);
 | |
| 		}
 | |
| #ifdef USE_PCM
 | |
| 		if (phandle) {
 | |
| 			if (snd_pcm_file_descriptor(phandle) > max)
 | |
| 				max = snd_pcm_file_descriptor(phandle);
 | |
| 			FD_SET(snd_pcm_file_descriptor(phandle), &out);
 | |
| 		}
 | |
| #endif
 | |
| 		if (select(max + 1, &in, &out, NULL, NULL) < 0)
 | |
| 			break;
 | |
| #ifdef USE_PCM
 | |
| 		if (phandle && FD_ISSET(snd_pcm_file_descriptor(phandle), &out)) {
 | |
| 			if (snd_pcm_write(phandle, pbuf, pfragment_size) != pfragment_size) {
 | |
| 				fprintf(stderr, "Playback write error!!\n");
 | |
| 				exit(0);
 | |
| 			}
 | |
| 		}
 | |
| #endif
 | |
| 		if (FD_ISSET(snd_seq_file_descriptor(handle), &out))
 | |
| 			snd_seq_flush_output(handle);
 | |
| 		if (FD_ISSET(snd_seq_file_descriptor(handle), &in)) {
 | |
| 			do {
 | |
| 				if ((err = snd_seq_event_input(handle, &ev))<0)
 | |
| 					break;
 | |
| 				if (!ev)
 | |
| 					continue;
 | |
| 				if (ev->type == SND_SEQ_EVENT_ECHO)
 | |
| 					send_event(handle, queue, client, port.port, &sub, &time);
 | |
| 				decode_event(ev);
 | |
| 				snd_seq_free_event(ev);
 | |
| 			} while (err > 0);
 | |
| 		}
 | |
| 	}
 | |
| }
 | 
