Move backend implementations to subdirectory

1 files changed, 0 insertions, 366 deletions

diff --git a/midi.c b/midi.c
deleted file mode 100644
index d856ced..0000000
--- a/midi.c
+++ /dev/null
@@ -1,366 +0,0 @@
-#include <string.h>
-#include <alsa/asoundlib.h>
-#include "midi.h"
-
-#define BACKEND_NAME "midi"
-static snd_seq_t* sequencer = NULL;
-typedef union {
-	struct {
-		uint8_t pad[5];
-		uint8_t type;
-		uint8_t channel;
-		uint8_t control;
-	} fields;
-	uint64_t label;
-} midi_channel_ident;
-
-/*
- * TODO
- * 	Optionally send note-off messages
- * 	Optionally send updates as after-touch
- */
-
-enum /*_midi_channel_type*/ {
-	none = 0,
-	note,
-	cc,
-	nrpn,
-	sysmsg
-};
-
-int init(){
-	backend midi = {
-		.name = BACKEND_NAME,
-		.conf = midi_configure,
-		.create = midi_instance,
-		.conf_instance = midi_configure_instance,
-		.channel = midi_channel,
-		.handle = midi_set,
-		.process = midi_handle,
-		.start = midi_start,
-		.shutdown = midi_shutdown
-	};
-
-	if(snd_seq_open(&sequencer, "default", SND_SEQ_OPEN_DUPLEX, 0) < 0){
-		fprintf(stderr, "Failed to open ALSA sequencer\n");
-		return 1;
-	}
-
-	//register backend
-	if(mm_backend_register(midi)){
-		fprintf(stderr, "Failed to register MIDI backend\n");
-		return 1;
-	}
-
-	snd_seq_nonblock(sequencer, 1);		
-		
-	fprintf(stderr, "MIDI client ID is %d\n", snd_seq_client_id(sequencer));
-	return 0;
-}
-
-static int midi_configure(char* option, char* value){
-	if(!strcmp(option, "name")){
-		if(snd_seq_set_client_name(sequencer, value) < 0){
-			fprintf(stderr, "Failed to set MIDI client name to %s\n", value);
-			return 1;
-		}
-		return 0;
-	}
-
-	fprintf(stderr, "Unknown MIDI backend option %s\n", option);
-	return 1;
-}
-
-static instance* midi_instance(){
-	instance* inst = mm_instance();
-	if(!inst){
-		return NULL;
-	}
-
-	inst->impl = calloc(1, sizeof(midi_instance_data));
-	if(!inst->impl){
-		fprintf(stderr, "Failed to allocate memory\n");
-		return NULL;
-	}
-
-	return inst;
-}
-
-static int midi_configure_instance(instance* instance, char* option, char* value){
-	midi_instance_data* data = (midi_instance_data*) instance->impl;
-
-	//FIXME maybe allow connecting more than one device
-	if(!strcmp(option, "read")){
-		//connect input device
-		if(data->read){
-			fprintf(stderr, "MIDI port already connected to an input device\n");
-			return 1;
-		}
-		data->read = strdup(value);
-		return 0;
-	}
-	else if(!strcmp(option, "write")){
-		//connect output device
-		if(data->write){
-			fprintf(stderr, "MIDI port already connected to an output device\n");
-			return 1;
-		}
-		data->write = strdup(value);
-		return 0;
-	}
-
-	fprintf(stderr, "Unknown MIDI instance option %s\n", option);
-	return 1;
-}
-
-static channel* midi_channel(instance* instance, char* spec){
-	midi_channel_ident ident = {
-		.label = 0
-	};
-
-	char* channel;
-
-	if(!strncmp(spec, "cc", 2)){
-		ident.fields.type = cc;
-		channel = spec + 2;
-	}
-	else if(!strncmp(spec, "note", 4)){
-		ident.fields.type = note;
-		channel = spec + 4;
-	}
-	else if(!strncmp(spec, "nrpn", 4)){
-		ident.fields.type = nrpn;
-		channel = spec + 4;
-	}
-	else{
-		fprintf(stderr, "Unknown MIDI channel specification %s\n", spec);
-		return NULL;
-	}
-
-	ident.fields.channel = strtoul(channel, &channel, 10);
-
-	//FIXME test this
-	if(ident.fields.channel > 16){
-		fprintf(stderr, "MIDI channel out of range in channel spec %s\n", spec);
-		return NULL;
-	}
-
-	if(*channel != '.'){
-		fprintf(stderr, "Need MIDI channel specification of form channel.control, had %s\n", spec);
-		return NULL;
-	}
-	channel++;
-
-	ident.fields.control = strtoul(channel, NULL, 10);
-
-	if(ident.label){
-		return mm_channel(instance, ident.label, 1);
-	}
-
-	return NULL;
-}
-
-static int midi_set(instance* inst, size_t num, channel** c, channel_value* v){
-	size_t u;
-	snd_seq_event_t ev;
-	midi_instance_data* data;
-	midi_channel_ident ident = {
-		.label = 0
-	};
-
-	for(u = 0; u < num; u++){
-		data = (midi_instance_data*) c[u]->instance->impl;
-		ident.label = c[u]->ident;
-
-		snd_seq_ev_clear(&ev);
-		snd_seq_ev_set_source(&ev, data->port);
-		snd_seq_ev_set_subs(&ev);
-		snd_seq_ev_set_direct(&ev);
-		
-		switch(ident.fields.type){
-			case note:
-				snd_seq_ev_set_noteon(&ev, ident.fields.channel, ident.fields.control, v[u].normalised * 127.0);
-				break;
-			case cc:
-				snd_seq_ev_set_controller(&ev, ident.fields.channel, ident.fields.control, v[u].normalised * 127.0);
-				break;
-			case nrpn:
-				//FIXME set to nrpn output
-				break;
-		}
-
-		snd_seq_event_output(sequencer, &ev);
-	}
-
-	snd_seq_drain_output(sequencer);
-	return 0;
-}
-
-static int midi_handle(size_t num, managed_fd* fds){
-	snd_seq_event_t* ev = NULL;
-	instance* inst = NULL;
-	channel* changed = NULL;
-	channel_value val;
-	midi_channel_ident ident = {
-		.label = 0
-	};
-
-	if(!num){
-		return 0;
-	}
-
-	while(snd_seq_event_input(sequencer, &ev) > 0){
-		ident.label = 0;
-		switch(ev->type){
-			case SND_SEQ_EVENT_NOTEON:
-			case SND_SEQ_EVENT_NOTEOFF:
-			case SND_SEQ_EVENT_KEYPRESS:
-			case SND_SEQ_EVENT_NOTE:
-				ident.fields.type = note;
-				ident.fields.channel = ev->data.note.channel;
-				ident.fields.control = ev->data.note.note;
-				val.normalised = (double)ev->data.note.velocity / 127.0;
-				break;
-			case SND_SEQ_EVENT_CONTROLLER:
-				ident.fields.type = cc;
-				ident.fields.channel = ev->data.control.channel;
-				ident.fields.control = ev->data.control.param;
-				val.raw.u64 = ev->data.control.value;
-				val.normalised = (double)ev->data.control.value / 127.0;
-				break;
-			case SND_SEQ_EVENT_CONTROL14:
-			case SND_SEQ_EVENT_NONREGPARAM:
-			case SND_SEQ_EVENT_REGPARAM:
-				//FIXME value calculation
-				ident.fields.type = nrpn;
-				ident.fields.channel = ev->data.control.channel;
-				ident.fields.control = ev->data.control.param;
-				break;
-			default:
-				fprintf(stderr, "Ignored MIDI event of unsupported type\n");
-				continue;
-		}
-
-		inst = mm_instance_find(BACKEND_NAME, ev->dest.port);
-		if(!inst){
-			//FIXME might want to return failure
-			fprintf(stderr, "Delivered MIDI event did not match any instance\n");
-			continue;
-		}
-
-		changed = mm_channel(inst, ident.label, 0);
-		if(changed){
-			if(mm_channel_event(changed, val)){
-				free(ev);
-				return 1;
-			}
-		}
-	}
-	free(ev);
-	return 0;
-}
-
-static int midi_start(){
-	size_t n, p;
-	int nfds, rv = 1;
-	struct pollfd* pfds = NULL;
-	instance** inst = NULL;
-	midi_instance_data* data = NULL;
-	snd_seq_addr_t addr;
-
-	if(mm_backend_instances(BACKEND_NAME, &n, &inst)){
-		fprintf(stderr, "Failed to fetch instance list\n");
-		return 1;
-	}
-
-	//if there are no ports, do nothing
-	if(!n){
-		free(inst);
-		return 0;
-	}
-
-	//create all ports
-	for(p = 0; p < n; p++){
-		data = (midi_instance_data*) inst[p]->impl;
-		data->port = snd_seq_create_simple_port(sequencer, inst[p]->name, SND_SEQ_PORT_CAP_WRITE | SND_SEQ_PORT_CAP_SUBS_WRITE | SND_SEQ_PORT_CAP_READ | SND_SEQ_PORT_CAP_SUBS_READ, SND_SEQ_PORT_TYPE_MIDI_GENERIC);
-		inst[p]->ident = data->port;
-
-		//make connections
-		if(data->write){
-			if(snd_seq_parse_address(sequencer, &addr, data->write) == 0){
-				fprintf(stderr, "Connecting output of instance %s to MIDI device %s (%d:%d)\n", inst[p]->name, data->write, addr.client, addr.port);
-				snd_seq_connect_to(sequencer, data->port, addr.client, addr.port);
-			}
-			else{
-				fprintf(stderr, "Failed to get destination MIDI device address: %s\n", data->write);
-			}
-			free(data->write);
-			data->write = NULL;
-		}
-
-		if(data->read){
-			if(snd_seq_parse_address(sequencer, &addr, data->read) == 0){
-				fprintf(stderr, "Connecting input from MIDI device %s to instance %s (%d:%d)\n", data->read, inst[p]->name, addr.client, addr.port);
-				snd_seq_connect_from(sequencer, data->port, addr.client, addr.port);
-			}
-			else{
-				fprintf(stderr, "Failed to get source MIDI device address: %s\n", data->read);
-			}
-			free(data->read);
-			data->read = NULL;
-		}
-	}
-
-	//register all fds to core
-	nfds = snd_seq_poll_descriptors_count(sequencer, POLLIN | POLLOUT);	
-	pfds = calloc(nfds, sizeof(struct pollfd));
-	if(!pfds){
-		fprintf(stderr, "Failed to allocate memory\n");
-		goto bail;
-	}
-	nfds = snd_seq_poll_descriptors(sequencer, pfds, nfds, POLLIN | POLLOUT);	
-
-	fprintf(stderr, "MIDI backend registering %d descriptors to core\n", nfds);
-	for(p = 0; p < nfds; p++){
-		if(mm_manage_fd(pfds[p].fd, BACKEND_NAME, 1, NULL)){
-			goto bail;
-		}
-	}
-
-	rv = 0;
-
-bail:
-	free(pfds);
-	free(inst);
-	return rv;
-}
-
-static int midi_shutdown(){
-	size_t n, p;
-	instance** inst = NULL;
-	midi_instance_data* data = NULL;
-	if(mm_backend_instances(BACKEND_NAME, &n, &inst)){
-		fprintf(stderr, "Failed to fetch instance list\n");
-		return 1;
-	}
-
-	for(p = 0; p < n; p++){
-		data = (midi_instance_data*) inst[p]->impl;
-		free(data->read);
-		free(data->write);
-		data->read = NULL;
-		data->write = NULL;
-		free(inst[p]->impl);
-	}
-	free(inst);
-
-	//close midi
-	snd_seq_close(sequencer);
-	sequencer = NULL;
-
-	//free configuration cache
-	snd_config_update_free_global();
-
-	fprintf(stderr, "MIDI backend shut down\n");
-	return 0;
-}