Rough rtpmidi backend skeleton

3 files changed, 225 insertions, 1 deletions

diff --git a/backends/Makefile b/backends/Makefile
index 446ad70..771e97e 100644
--- a/backends/Makefile
+++ b/backends/Makefile
@@ -1,6 +1,6 @@
 .PHONY: all clean
 LINUX_BACKENDS = midi.so evdev.so
-BACKENDS = artnet.so osc.so loopback.so sacn.so
+BACKENDS = artnet.so osc.so loopback.so sacn.so rtpmidi.so
 
 SYSTEM := $(shell uname -s)
 
diff --git a/backends/rtpmidi.c b/backends/rtpmidi.c
new file mode 100644
index 0000000..f77f93b
--- /dev/null
+++ b/backends/rtpmidi.c
@@ -0,0 +1,130 @@
+#include <string.h>
+#include <unistd.h>
+
+#include "rtpmidi.h"
+
+#define BACKEND_NAME "rtpmidi"
+
+/** rtpMIDI backend w/ AppleMIDI support
+ *
+ * Global configuration
+ * 	bind = 0.0.0.0
+ * 	apple-bind = 0.0.0.1
+ * 	mdns-bind = 0.0.0.0
+ * 	mdns-name = mdns-name
+ * 
+ * Instance configuration
+ * 	interface = 0
+ * 	(opt) ssrc = X
+ *
+ * 	apple-session = session-name
+ * 	apple-invite = invite-peer
+ * 	apple-allow = *
+ * or
+ * 	connect = 
+ * 	reply-any = 1
+ */
+
+static struct /*_rtpmidi_global*/ {
+	int mdns_fd;
+	char* mdns_name;
+	size_t nfds;
+	rtpmidi_fd* fds;
+} cfg = {
+	.mdns_fd = -1,
+	.mdns_name = NULL,
+	.nfds = 0,
+	.fds = NULL
+};
+
+int init(){
+	backend rtpmidi = {
+		.name = BACKEND_NAME,
+		.conf = rtpmidi_configure,
+		.create = rtpmidi_instance,
+		.conf_instance = rtpmidi_configure_instance,
+		.channel = rtpmidi_channel,
+		.handle = rtpmidi_set,
+		.process = rtpmidi_handle,
+		.start = rtpmidi_start,
+		.shutdown = rtpmidi_shutdown
+	};
+
+	if(mm_backend_register(rtpmidi)){
+		fprintf(stderr, "Failed to register rtpMIDI backend\n");
+		return 1;
+	}
+
+	return 0;
+}
+
+static int rtpmidi_configure(char* option, char* value){
+	if(!strcmp(option, "mdns-name")){
+		if(cfg.mdns_name){
+			free(cfg.mdns_name);
+		}
+
+		cfg.mdns_name = strdup(value);
+		if(!cfg.mdns_name){
+			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, "bind")){
+		//TODO open listening control and data fds
+	}
+
+	fprintf(stderr, "Unknown rtpMIDI backend option %s\n", option);
+	return 1;
+}
+
+static int rtpmidi_configure_instance(instance* inst, char* option, char* value){
+	//TODO
+	return 1;
+}
+
+static instance* rtpmidi_instance(){
+	//TODO
+	return NULL;
+}
+
+static channel* rtpmidi_channel(instance* inst, char* spec){
+	//TODO
+	return NULL;
+}
+
+static int rtpmidi_set(instance* inst, size_t num, channel** c, channel_value* v){
+	//TODO
+	return 1;
+}
+
+static int rtpmidi_handle(size_t num, managed_fd* fds){
+	//TODO
+	return 1;
+}
+
+static int rtpmidi_start(){
+	//TODO
+	return 1;
+}
+
+static int rtpmidi_shutdown(){
+	size_t u;
+
+	free(cfg.mdns_name);
+	if(cfg.mdns_fd >= 0){
+		close(cfg.mdns_fd);
+	}
+
+	for(u = 0; u < cfg.nfds; u++){
+		if(cfg.fds[u].data >= 0){
+			close(cfg.fds[u].data);
+		}
+		if(cfg.fds[u].control >= 0){
+			close(cfg.fds[u].control);
+		}
+	}
+	return 0;
+}
diff --git a/backends/rtpmidi.h b/backends/rtpmidi.h
new file mode 100644
index 0000000..f14357f
--- /dev/null
+++ b/backends/rtpmidi.h
@@ -0,0 +1,94 @@
+#include <sys/socket.h>
+#include "midimonster.h"
+
+int init();
+static int rtpmidi_configure(char* option, char* value);
+static int rtpmidi_configure_instance(instance* instance, char* option, char* value);
+static instance* rtpmidi_instance();
+static channel* rtpmidi_channel(instance* instance, char* spec);
+static int rtpmidi_set(instance* inst, size_t num, channel** c, channel_value* v);
+static int rtpmidi_handle(size_t num, managed_fd* fds);
+static int rtpmidi_start();
+static int rtpmidi_shutdown();
+
+#define RTPMIDI_DEFAULT_PORTBASE "9001"
+#define RTPMIDI_RECV_BUF 4096
+
+#define RTPMIDI_COMMAND_LEN
+#define RTPMIDI_COMMAND_DATA_OFFSET
+#define RTPMIDI_HAS_JOURNAL
+#define RTPMIDI_IS_PHANTOM
+
+typedef enum /*_rtpmidi_peer_mode*/ {
+	peer_learned,
+	peer_invited,
+	peer_invited_by,
+	peer_sync,
+	peer_connect
+} rtpmidi_peer_mode;
+
+typedef struct /*_rtpmidi_peer*/ {
+	rtpmidi_peer_mode mode;
+	struct sockaddr_storage dest;
+	socklen_t dest_len;
+	uint32_t ssrc;
+} rtpmidi_peer;
+
+typedef struct /*_rtpmidi_fd*/ {
+	int data;
+	int control;
+} rtpmidi_fd;
+
+typedef struct /*_rtmidi_instance_data*/ {
+	size_t fd_index;
+	size_t npeers;
+	rtpmidi_peer* peers;
+	uint32_t ssrc;
+
+	//apple-midi config
+	char* session_name;
+	char* invite_peers;
+	char* invite_accept;
+
+	//generic mode config
+	uint8_t learn_peers;
+} rtpmidi_instance_data;
+
+#pragma pack(push, 1)
+typedef struct /*_apple_session_command*/ {
+	uint16_t res1;
+	uint8_t command[2];
+	uint32_t version;
+	uint32_t token;
+	uint32_t ssrc;
+	//char* name
+} apple_command;
+
+typedef struct /*_apple_session_sync*/ {
+	uint16_t res1;
+	uint8_t command[2];
+	uint32_t ssrc;
+	uint8_t count;
+	uint8_t res2[3];
+	uint64_t timestamp[3];
+} apple_sync;
+
+typedef struct /*_apple_session_feedback*/ {
+	uint16_t res1;
+	uint8_t command[2];
+	uint32_t ssrc;
+	uint32_t sequence;
+} apple_feedback;
+
+typedef struct /*_rtp_midi_header*/ {
+	uint16_t vpxccmpt; //this is really just an amalgamated constant value
+	uint16_t sequence;
+	uint32_t timestamp;
+	uint32_t ssrc;
+} rtpmidi_header;
+
+typedef struct /*_rtp_midi_command*/ {
+	uint8_t flags;
+	uint8_t additional_length;
+} rtpmidi_command;
+#pragma pack(pop)