Allow multiple clients (up to 4) to transmit audio at once

Assign the 4 VOIP audio streams dynamically to transmitting
clients via snis_server, decode and mix the VOIP audio streams
on the clients.

Signed-off-by: Stephen M. Cameron <stephenmcameron@gmail.com>

Makefile

@@ -505,7 +505,7 @@ _SERVEROBJS=snis_server.o starbase-comms.o \
 		snis_server_tracker.o snis_bridge_update_packet.o solarsystem_config.o a_star.o \
 		key_value_parser.o nonuniform_random_sampler.o oriented_bounding_box.o shape_collision.o \
 		graph_dev_mesh_stub.o turret_aimer.o snis_hash.o snis_server_debug.o \
-		ship_registration.o
+		ship_registration.o talking_stick.o
 SERVEROBJS=${COMMONOBJS} $(patsubst %,$(OD)/%,${_SERVEROBJS})
 
 _MULTIVERSEOBJS=snis_multiverse.o snis_marshal.o snis_socket_io.o mathutils.o mtwist.o stacktrace.o \
@@ -1106,6 +1106,9 @@ $(OD)/mtwist.o:	mtwist.c Makefile ${ODT}
 $(OD)/elastic_collision.o:	elastic_collision.c elastic_collision.h Makefile ${ODT}
 	$(Q)$(COMPILE)
 
+$(OD)/talking_stick.o:	talking_stick.c talking_stick.h Makefile ${ODT}
+	$(Q)$(COMPILE)
+
 $(OD)/fleet.o:	fleet.c Makefile ${ODT}
 	$(Q)$(COMPILE)
 

snis.h

@@ -41,7 +41,7 @@
 #include "shape_collision.h"
 
 #define DEFAULT_SOLAR_SYSTEM "default"
-#define SNIS_PROTOCOL_VERSION "SNIS051"
+#define SNIS_PROTOCOL_VERSION "SNIS052"
 #define COMMON_MTWIST_SEED 97872
 /* dimensions of the "known" universe */
 #define XKNOWN_DIM 600000.0

snis_client.c

@@ -196,6 +196,8 @@ static float current_altitude = 1e20;
 static int idiot_light_threshold = 10; /* tweakable */
 static int dejitter_science_details = 1; /* Tweakable. 1 means de-jitter science details, 0 means don't */
 static int monitor_voice_chat = 0;
+static int have_talking_stick = 0;
+static pthread_mutex_t voip_mutex = PTHREAD_MUTEX_INITIALIZER;
 
 /* I can switch out the line drawing function with these macros */
 /* in case I come across something faster than gdk_draw_line */
@@ -4380,6 +4382,19 @@ static void deal_with_keyboard()
 	}
 }
 
+static void request_talking_stick(void)
+{
+	queue_to_server(snis_opcode_subcode_pkt("bb", OPCODE_TALKING_STICK, OPCODE_TALKING_STICK_REQUEST));
+}
+
+static void release_talking_stick(void)
+{
+	queue_to_server(snis_opcode_subcode_pkt("bb", OPCODE_TALKING_STICK, OPCODE_TALKING_STICK_RELEASE));
+	pthread_mutex_lock(&voip_mutex);
+	have_talking_stick = 0;
+	pthread_mutex_unlock(&voip_mutex);
+}
+
 static gint key_press_cb(GtkWidget* widget, GdkEventKey* event, gpointer data)
 {
 	enum keyaction ka;
@@ -4399,6 +4414,15 @@ static gint key_press_cb(GtkWidget* widget, GdkEventKey* event, gpointer data)
 	}
 
 	if (event->keyval == GDK_F12) {
+		pthread_mutex_lock(&voip_mutex);
+			if (!have_talking_stick) {
+				pthread_mutex_unlock(&voip_mutex);
+				request_talking_stick();
+			} else {
+				pthread_mutex_unlock(&voip_mutex);
+			}
+		/* We transmit regardless of whether we have a talking stick.
+		 * If we do not have it, snis_server will drop our messages */
 		if (control_key_pressed)
 			voice_chat_start_recording(VOICE_CHAT_DESTINATION_ALL, 0);
 		else
@@ -4648,8 +4672,11 @@ static gint key_release_cb(GtkWidget* widget, GdkEventKey* event, gpointer data)
 	if (ka > 0 && ka < NKEYSTATES)
 		kbstate.pressed[ka] = 0;
 
-	if (event->keyval == GDK_F12)
+	if (event->keyval == GDK_F12) {
 		voice_chat_stop_recording();
+		/* We release even if we don't have, snis_server will know the real deal. */
+		release_talking_stick();
+	}
 
 	return FALSE;
 }
@@ -7701,12 +7728,13 @@ static int process_opus_audio_data(void)
 {
 	int rc;
 	uint8_t buffer[4008];
+	uint16_t audio_chain;
 	uint8_t destination;
 	uint32_t radio_channel;
 	uint16_t datalen;
 
-	rc = read_and_unpack_buffer(buffer, "bwh",
-			&destination, &radio_channel, &datalen);
+	rc = read_and_unpack_buffer(buffer, "bhwh",
+			&audio_chain, &destination, &radio_channel, &datalen);
 	if (rc)
 		return rc;
 	if (datalen > 4000) {
@@ -7717,7 +7745,31 @@ static int process_opus_audio_data(void)
 	rc = snis_readsocket(gameserver_sock, buffer, datalen);
 	if (rc)
 		return rc;
-	voice_chat_play_opus_packet(buffer, datalen);
+	if (audio_chain < WWVIAUDIO_CHAIN_COUNT)
+		voice_chat_play_opus_packet(buffer, datalen, audio_chain);
+	return 0;
+}
+
+static int process_talking_stick(void)
+{
+	uint8_t buffer[10];
+	uint8_t subcode;
+	int rc;
+
+	rc = read_and_unpack_buffer(buffer, "b", &subcode);
+	if (rc)
+		return rc;
+	switch (subcode) {
+	case OPCODE_TALKING_STICK_GRANT:
+		pthread_mutex_lock(&voip_mutex);
+		have_talking_stick = 1;
+		pthread_mutex_unlock(&voip_mutex);
+		break;
+	default:
+		fprintf(stderr, "%s: Unexpected OPCODE_TALKING_STICK subcode %hhu\n",
+				"snis_client", subcode);
+		return -1;
+	}
 	return 0;
 }
 
@@ -8036,6 +8088,11 @@ static void *gameserver_reader(__attribute__((unused)) void *arg)
 			if (rc)
 				goto protocol_error;
 			break;
+		case OPCODE_TALKING_STICK:
+			rc = process_talking_stick();
+			if (rc)
+				goto protocol_error;
+			break;
 		default:
 			goto protocol_error;
 		}

snis_opcode_def.c

@@ -78,6 +78,9 @@ int snis_opcode_def_init(void)
 	rc |= init_opcode_def(OPCODE_ID_CLIENT_SHIP, "bw");
 	rc |= init_opcode_def(OPCODE_UPDATE_ASTEROID, "bwwSSS");
 	rc |= init_opcode_def(OPCODE_UPDATE_ASTEROID_MINERALS, "bwbbbb");
+	rc |= init_opcode_subcode_def(OPCODE_TALKING_STICK, OPCODE_TALKING_STICK_REQUEST, "bb");
+	rc |= init_opcode_subcode_def(OPCODE_TALKING_STICK, OPCODE_TALKING_STICK_GRANT, "bb");
+	rc |= init_opcode_subcode_def(OPCODE_TALKING_STICK, OPCODE_TALKING_STICK_RELEASE, "bb");
 	rc |= init_opcode_def(OPCODE_UPDATE_WARP_CORE, "bwwSSS");
 	rc |= init_opcode_def(OPCODE_DEMON_RTSMODE, "bb");
 	rc |= init_opcode_subcode_def(OPCODE_RTS_FUNC, OPCODE_RTS_FUNC_COMMS_BUTTON, "bbb");
@@ -222,8 +225,8 @@ int snis_opcode_def_init(void)
 	rc |= init_opcode_def(OPCODE_LOAD_SKYBOX, "n/a");
 	rc |= init_opcode_def(OPCODE_ROBOT_AUTO_MANUAL, "bb");
 	rc |= init_opcode_def(OPCODE_ADD_WARP_EFFECT, "bwSSSSSS");
-	/* rc |= init_opcode_def(OPCODE_OPUS_AUDIO_DATA, "bbwhr"); */
-			/* ^^^ opcode, destination, channel, bytecount, audio data */
+	/* rc |= init_opcode_def(OPCODE_OPUS_AUDIO_DATA, "bhbwhr"); */
+			/* ^^^ opcode, audio chain, destination, channel, bytecount, audio data */
 	rc |= init_opcode_def(OPCODE_REQUEST_PITCH, "bb");
 	rc |= init_opcode_def(OPCODE_REQUEST_ROLL, "bb");
 	rc |= init_opcode_def(OPCODE_REQUEST_SCIBALL_YAW, "bb");

snis_packet.h

@@ -182,7 +182,10 @@
 #define OPCODE_REQUEST_WEAPONS_YAW_PITCH 198
 #define OPCODE_UPDATE_COOLANT_DATA	199
 #define OPCODE_UPDATE_ASTEROID_MINERALS 200
-/* UNUSED OPCODE 201 */
+#define OPCODE_TALKING_STICK		201
+#define		OPCODE_TALKING_STICK_REQUEST	1
+#define		OPCODE_TALKING_STICK_GRANT	2
+#define		OPCODE_TALKING_STICK_RELEASE	3
 /* UNUSED OPCODE 202 */
 /* UNUSED OPCODE 203 */
 /* UNUSED OPCODE 204 */

snis_server.c

@@ -122,9 +122,12 @@
 #include "planetary_ring_data.h"
 #include "scipher.h"
 #include "snis_voice_chat.h"
+#include "talking_stick.h"
+#include "wwviaudio.h" /* Just for WWVIAUDIO_CHAIN_COUNT */
 
 #define CLIENT_UPDATE_PERIOD_NSECS 500000000
 #define MAXCLIENTS 100
+#define NTALKING_STICKS (WWVIAUDIO_CHAIN_COUNT)
 
 /*
  * The following globals are adjustable at runtime via the demon console.
@@ -427,6 +430,8 @@ static struct game_client {
 	uint8_t current_station; /* what station (displaymode) client is currently on. Mostly the server doesn't */
 				/* need to know this, but uses it for demon serverside builtin commands "clients" */
 				/* "lockroles", and "rotateroles" */
+	int16_t talking_stick;	/* Which audio chain VOIP transmissions from this client should use. */
+				/* -1 if none assigned */
 #define COMPUTE_AVERAGE_TO_CLIENT_BUFFER_SIZE 0
 #if COMPUTE_AVERAGE_TO_CLIENT_BUFFER_SIZE
 	uint64_t write_sum;	/* Statistics about data written to client */
@@ -706,6 +711,8 @@ static void put_client(struct game_client *c)
 	c->refcount--;
 	fprintf(stderr, "snis_server: client refcount = %d\n", c->refcount);
 	if (c->refcount == 0) {
+		if (c->talking_stick != NO_TALKING_STICK)
+			talking_stick_release(c->talking_stick);
 		if (c->bridge >= 0 && c->bridge < nbridges) {
 			bridgelist[c->bridge].nclients--;
 			fprintf(stderr, "snis_server: client count of bridge %d = %d\n", c->bridge, bridgelist[c->bridge].nclients);
@@ -20050,14 +20057,16 @@ static int process_opus_audio_data(struct game_client *c)
 {
 	int rc;
 	uint8_t buffer[4008];
+	uint16_t ignored;
+	int16_t audio_chain;
 	uint8_t destination;
 	uint32_t radio_channel;
 	uint16_t datalen;
 	struct packed_buffer *pb;
 	struct except_clients except;
 
-	rc = read_and_unpack_buffer(c, buffer, "bwh",
-			&destination, &radio_channel, &datalen);
+	rc = read_and_unpack_buffer(c, buffer, "hbwh",
+			&ignored, &destination, &radio_channel, &datalen);
 	if (rc)
 		return rc;
 	if (datalen > 4000) {
@@ -20068,9 +20077,22 @@ static int process_opus_audio_data(struct game_client *c)
 	rc = snis_readsocket(c->socket, buffer, datalen);
 	if (rc)
 		return rc;
-	pb = packed_buffer_allocate(8 + datalen);
-	packed_buffer_append(pb, "bbwhr", OPCODE_OPUS_AUDIO_DATA,
-				destination, radio_channel, datalen, buffer, datalen);
+
+	pthread_mutex_lock(&universe_mutex);
+	client_lock();
+	if (c->talking_stick == NO_TALKING_STICK) {
+		/* Client does not have talking stick. */
+		client_unlock();
+		pthread_mutex_unlock(&universe_mutex);
+		return 0;
+	}
+	/* Ignore audio chain from client, it put 255 there anyway 'cause it doesn't know */
+	audio_chain = c->talking_stick;
+	client_unlock();
+	pthread_mutex_unlock(&universe_mutex);
+	pb = packed_buffer_allocate(10 + datalen);
+	packed_buffer_append(pb, "bhbwhr", OPCODE_OPUS_AUDIO_DATA,
+				(uint16_t) audio_chain, destination, radio_channel, datalen, buffer, datalen);
 
 	/* Don't send a client's own audio back at him. */
 	except.nclients = 1;
@@ -20092,6 +20114,46 @@ static int process_opus_audio_data(struct game_client *c)
 	return 0;
 }
 
+static int process_talking_stick(struct game_client *c)
+{
+	int rc;
+	uint8_t subcode;
+	unsigned char buffer[20];
+	int16_t ts;
+
+	rc = read_and_unpack_buffer(c, buffer, "b", &subcode);
+	if (rc)
+		return rc;
+	switch (subcode) {
+	case OPCODE_TALKING_STICK_REQUEST:
+		pthread_mutex_lock(&universe_mutex);
+		client_lock();
+		if (c->talking_stick == NO_TALKING_STICK)
+			c->talking_stick = talking_stick_get();
+			ts = c->talking_stick;
+		client_unlock();
+		pthread_mutex_unlock(&universe_mutex);
+		if (ts > 0)
+			pb_queue_to_client(c, snis_opcode_subcode_pkt("bb",
+				OPCODE_TALKING_STICK, OPCODE_TALKING_STICK_GRANT));
+		break;
+	case OPCODE_TALKING_STICK_RELEASE:
+		pthread_mutex_lock(&universe_mutex);
+		client_lock();
+		if (c->talking_stick != NO_TALKING_STICK)
+			talking_stick_release(c->talking_stick);
+			c->talking_stick = NO_TALKING_STICK;
+		client_unlock();
+		pthread_mutex_unlock(&universe_mutex);
+		break;
+	default:
+		fprintf(stderr, "%s: bad OPCODE_TALKING_STICK subcode %hhu in request from client\n",
+				logprefix(), subcode);
+		return -1;
+	}
+	return 0;
+}
+
 static int process_toggle_demon_ai_debug_mode(struct game_client *c)
 {
 	c->debug_ai = !c->debug_ai;
@@ -22831,6 +22893,11 @@ static void process_instructions_from_client(struct game_client *c)
 			if (rc)
 				goto protocol_error;
 			break;
+		case OPCODE_TALKING_STICK:
+			rc = process_talking_stick(c);
+			if (rc)
+				goto protocol_error;
+			break;
 		default:
 			goto protocol_error;
 	}
@@ -24491,6 +24558,7 @@ static void service_connection(int connection)
 	client[i].socket = connection;
 	client[i].timestamp = 0;  /* newborn client, needs everything */
 	client[i].current_station = 255; /* unknown */
+	client[i].talking_stick = NO_TALKING_STICK; /* No VOIP channel assigned */
 
 	log_client_info(SNIS_INFO, connection, "add new player\n");
 
@@ -29844,6 +29912,7 @@ int main(int argc, char *argv[])
 	snis_protocol_debugging(1);
 	snis_debug_dump_set_label("SERVER");
 	snis_opcode_def_init();
+	talking_stick_setup(NTALKING_STICKS);
 
 	memset(&thirtieth_second, 0, sizeof(thirtieth_second));
 	thirtieth_second.tv_nsec = 33333333; /* 1/30th second */