Make rtpmidi backend behave while not providing functionality

1 files changed, 165 insertions, 5 deletions

diff --git a/backends/rtpmidi.c b/backends/rtpmidi.c
index f77f93b..6a8032a 100644
--- a/backends/rtpmidi.c
+++ b/backends/rtpmidi.c
@@ -1,5 +1,11 @@
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <netdb.h>
 #include <string.h>
+#include <errno.h>
 #include <unistd.h>
+#include <fcntl.h>
+#include <ctype.h>
 
 #include "rtpmidi.h"
 
@@ -58,10 +64,118 @@ int init(){
 	return 0;
 }
 
+static int rtpmidi_listener(char* host, char* port){
+	int fd = -1, status, yes = 1, flags;
+	struct addrinfo hints = {
+		.ai_family = AF_UNSPEC,
+		.ai_socktype = SOCK_DGRAM,
+		.ai_flags = AI_PASSIVE
+	};
+	struct addrinfo* info;
+	struct addrinfo* addr_it;
+
+	status = getaddrinfo(host, port, &hints, &info);
+	if(status){
+		fprintf(stderr, "Failed to get socket info for %s port %s: %s\n", host, port, gai_strerror(status));
+		return -1;
+	}
+
+	for(addr_it = info; addr_it != NULL; addr_it = addr_it->ai_next){
+		fd = socket(addr_it->ai_family, addr_it->ai_socktype, addr_it->ai_protocol);
+		if(fd < 0){
+			continue;
+		}
+
+		yes = 1;
+		if(setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (void*)&yes, sizeof(yes)) < 0){
+			fprintf(stderr, "Failed to set SO_REUSEADDR on socket\n");
+		}
+
+		yes = 1;
+		if(setsockopt(fd, SOL_SOCKET, SO_BROADCAST, (void*)&yes, sizeof(yes)) < 0){
+			fprintf(stderr, "Failed to set SO_BROADCAST on socket\n");
+		}
+
+		yes = 0;
+		if(setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, (void*)&yes, sizeof(yes)) < 0){
+			fprintf(stderr, "Failed to unset IP_MULTICAST_LOOP option: %s\n", strerror(errno));
+		}
+
+		status = bind(fd, addr_it->ai_addr, addr_it->ai_addrlen);
+		if(status < 0){
+			close(fd);
+			continue;
+		}
+
+		break;
+	}
+
+	freeaddrinfo(info);
+
+	if(!addr_it){
+		fprintf(stderr, "Failed to create listening socket for %s port %s\n", host, port);
+		return -1;
+	}
+
+	//set nonblocking
+	flags = fcntl(fd, F_GETFL, 0);
+	if(fcntl(fd, F_SETFL, flags | O_NONBLOCK) < 0){
+		fprintf(stderr, "Failed to set rtpMIDI descriptor nonblocking\n");
+		close(fd);
+		return -1;
+	}
+	return 0;
+}
+
+static int rtpmidi_parse_addr(char* host, char* port, struct sockaddr_storage* addr, socklen_t* len){
+	struct addrinfo* head;
+	struct addrinfo hints = {
+		.ai_family = AF_UNSPEC,
+		.ai_socktype = SOCK_DGRAM
+	};
+
+	int error = getaddrinfo(host, port, &hints, &head);
+	if(error || !head){
+		fprintf(stderr, "Failed to parse address %s port %s: %s\n", host, port, gai_strerror(error));
+		return 1;
+	}
+
+	memcpy(addr, head->ai_addr, head->ai_addrlen);
+	*len = head->ai_addrlen;
+
+	freeaddrinfo(head);
+	return 0;
+}
+
+static int rtpmidi_separate_hostspec(char* in, char** host, char** port, char* default_port){
+	size_t u;
+
+	if(!in || !host || !port){
+		return 1;
+	}
+
+	for(u = 0; in[u] && !isspace(in[u]); u++){
+	}
+
+	//guess
+	*host = in;
+
+	if(in[u]){
+		in[u] = 0;
+		*port = in + u + 1;
+	}
+	else{
+		//no port given
+		*port = default_port;
+	}
+	return 0;
+}
+
 static int rtpmidi_configure(char* option, char* value){
 	if(!strcmp(option, "mdns-name")){
 		if(cfg.mdns_name){
-			free(cfg.mdns_name);
+			fprintf(stderr, "Duplicate mdns-name assignment\n");
+			return 1;
 		}
 
 		cfg.mdns_name = strdup(value);
@@ -69,11 +183,22 @@ static int rtpmidi_configure(char* option, char* value){
 			fprintf(stderr, "Failed to allocate memory\n");
 			return 1;
 		}
-		//TODO this should create the mdns broadcaster and responder socket
 		return 0;
 	}
+	else if(!strcmp(option, "mdns-bind")){
+		if(cfg.mdns_fd >= 0){
+			fprintf(stderr, "Only one mDNS discovery bind is supported\n");
+			return 1;
+		}
+
+
+		//TODO create mdns broadcast/responder socket
+	}
 	else if(!strcmp(option, "bind")){
-		//TODO open listening control and data fds
+		//TODO open listening data fd for raw rtpmidi instance
+	}
+	else if(!strcmp(option, "apple-bind")){
+		//TODO open control and data fd for applemidi session/rtpmidi+apple-extensions instance
 	}
 
 	fprintf(stderr, "Unknown rtpMIDI backend option %s\n", option);
@@ -101,13 +226,48 @@ static int rtpmidi_set(instance* inst, size_t num, channel** c, channel_value* v
 }
 
 static int rtpmidi_handle(size_t num, managed_fd* fds){
+	//TODO handle discovery
+
+	if(!num){
+		return 0;
+	}
+
 	//TODO
 	return 1;
 }
 
 static int rtpmidi_start(){
-	//TODO
-	return 1;
+	size_t n, u, p;
+	int rv = 1;
+	instance** inst = NULL;
+	rtpmidi_instance_data* data = NULL;
+
+	//fetch all defined instances
+	if(mm_backend_instances(BACKEND_NAME, &n, &inst)){
+		fprintf(stderr, "Failed to fetch instance list\n");
+		return 1;
+	}
+
+	if(!n){
+		free(inst);
+		return 0;
+	}
+
+	if(!cfg.nfds){
+		fprintf(stderr, "Failed to start rtpMIDI backend: no descriptors bound\n");
+		goto bail;
+	}
+
+	if(cfg.mdns_fd < 0){
+		fprintf(stderr, "No mDNS discovery interface bound, APPLEMIDI session support disabled\n");
+	}
+
+	//TODO initialize all instances
+
+	rv = 0;
+bail:
+	free(inst);
+	return rv;
 }
 
 static int rtpmidi_shutdown(){