add silent agent removal to AgentList class

interface/src/main.cpp

@@ -942,6 +942,9 @@ int main(int argc, char** argv)
     agentList.linkedDataCreateCallback = &attachNewHeadToAgent;
     agentList.audioMixerSocketUpdate = &audioMixerUpdate;
     
+    // start the thread which checks for silent agents
+    agentList.startSilentAgentRemovalThread();
+    
     // create thread for receipt of data via UDP
     pthread_create(&networkReceiveThread, NULL, networkReceive, NULL);
 

shared/src/Agent.cpp

@@ -10,10 +10,9 @@
 #include <arpa/inet.h>
 #include <cstring>
 #include "UDPSocket.h"
+#include "SharedUtil.h"
 
-Agent::Agent() {
-    
-}
+Agent::Agent() {}
 
 Agent::Agent(sockaddr *agentPublicSocket, sockaddr *agentLocalSocket, char agentType) {
     publicSocket = new sockaddr;
@@ -23,6 +22,7 @@ Agent::Agent(sockaddr *agentPublicSocket, sockaddr *agentLocalSocket, char agent
     memcpy(localSocket, agentLocalSocket, sizeof(sockaddr));
     
     type = agentType;
+    lastRecvTimeUsecs = usecTimestampNow();
     
     activeSocket = NULL;
     linkedData = NULL;

shared/src/Agent.h

@@ -28,6 +28,7 @@ class Agent {
         char type;
         timeval pingStarted;
         int pingMsecs;
+        double lastRecvTimeUsecs;
         bool isSelf;
         AgentData *linkedData;
     

shared/src/AgentList.cpp

@@ -8,6 +8,11 @@
 
 #include "AgentList.h"
 #include <arpa/inet.h>
+#include <pthread.h>
+#include "SharedUtil.h"
+
+bool stopAgentRemovalThread = false;
+pthread_mutex_t vectorChangeMutex = PTHREAD_MUTEX_INITIALIZER;
 
 AgentList::AgentList() : agentSocket(AGENT_SOCKET_LISTEN_PORT) {
     linkedDataCreateCallback = NULL;
@@ -15,7 +20,12 @@ AgentList::AgentList() : agentSocket(AGENT_SOCKET_LISTEN_PORT) {
 }
 
 AgentList::AgentList(int socketListenPort) : agentSocket(socketListenPort) {
-    
+    linkedDataCreateCallback = NULL;
+    audioMixerSocketUpdate = NULL;
+}
+
+AgentList::~AgentList() {
+    stopSilentAgentRemovalThread();
 }
 
 UDPSocket * AgentList::getAgentSocket() {
@@ -59,6 +69,8 @@ void AgentList::updateAgentWithData(sockaddr *senderAddress, void *packetData, s
     if (agentIndex != -1) {
         Agent *matchingAgent = &agents[agentIndex];
         
+        matchingAgent->lastRecvTimeUsecs = usecTimestampNow();
+        
         if (matchingAgent->linkedData == NULL) {
             if (linkedDataCreateCallback != NULL) {
                 linkedDataCreateCallback(matchingAgent);
@@ -135,7 +147,9 @@ bool AgentList::addOrUpdateAgent(sockaddr *publicSocket, sockaddr *localSocket,
         
         std::cout << "Added agent - " << &newAgent << "\n";
         
-        agents.push_back(newAgent);       
+        pthread_mutex_lock(&vectorChangeMutex);
+        agents.push_back(newAgent);
+        pthread_mutex_unlock(&vectorChangeMutex);
         
         return true;
     } else {
@@ -155,7 +169,6 @@ void AgentList::broadcastToAgents(char *broadcastData, size_t dataBytes) {
     }
 }
 
-
 void AgentList::pingAgents() {
     char payload[] = "P";
     
@@ -193,4 +206,39 @@ void AgentList::handlePingReply(sockaddr *agentAddress) {
             break;
         }
     }
+}
+
+void *removeSilentAgents(void *args) {
+    std::vector<Agent> *agents = (std::vector<Agent> *)args;
+    double checkTimeUSecs, sleepTime;
+    
+    while (!stopAgentRemovalThread) {
+        checkTimeUSecs = usecTimestampNow();
+        
+        for(std::vector<Agent>::iterator agent = agents->begin(); agent != agents->end();) {
+            if ((checkTimeUSecs - agent->lastRecvTimeUsecs) > AGENT_SILENCE_THRESHOLD_USECS) {
+                std::cout << "Killing agent " << &(*agent)  << "\n";
+                pthread_mutex_lock(&vectorChangeMutex);
+                agent = agents->erase(agent);
+                pthread_mutex_unlock(&vectorChangeMutex);
+            } else {
+                agent++;
+            }
+        }
+        
+        
+        sleepTime = AGENT_SILENCE_THRESHOLD_USECS - (usecTimestampNow() - checkTimeUSecs);
+        usleep(sleepTime);
+    }
+    
+    pthread_exit(0);
+}
+
+void AgentList::startSilentAgentRemovalThread() {
+    pthread_create(&removeSilentAgentsThread, NULL, removeSilentAgents, (void *)&agents);
+}
+
+void AgentList::stopSilentAgentRemovalThread() {
+    stopAgentRemovalThread = true;
+    pthread_join(removeSilentAgentsThread, NULL);
 }

shared/src/AgentList.h

@@ -15,11 +15,13 @@
 #include "UDPSocket.h"
 
 const unsigned short AGENT_SOCKET_LISTEN_PORT = 40103;
+const int AGENT_SILENCE_THRESHOLD_USECS = 2 * 1000000;
 
 class AgentList {
     public:
         AgentList();
         AgentList(int socketListenPort);
+        ~AgentList();
         std::vector<Agent> agents;
         void(*linkedDataCreateCallback)(Agent *);
         void(*audioMixerSocketUpdate)(in_addr_t, in_port_t);
@@ -30,12 +32,16 @@ class AgentList {
         bool addOrUpdateAgent(sockaddr *publicSocket, sockaddr *localSocket, char agentType);
         void processAgentData(sockaddr *senderAddress, void *packetData, size_t dataBytes);
         void broadcastToAgents(char *broadcastData, size_t dataBytes);
+        void sendToAgent(Agent *destAgent, void *packetData, size_t dataBytes);
         void pingAgents();
+        void startSilentAgentRemovalThread();
+        void stopSilentAgentRemovalThread();
     private:
-        UDPSocket agentSocket;
         int indexOfMatchingAgent(sockaddr *senderAddress);
         void updateAgentWithData(sockaddr *senderAddress, void *packetData, size_t dataBytes);
         void handlePingReply(sockaddr *agentAddress);
+        UDPSocket agentSocket;
+        pthread_t removeSilentAgentsThread;
 };
 
 #endif /* defined(__hifi__AgentList__) */

shared/src/SharedUtil.cpp

@@ -0,0 +1,19 @@
+//
+//  SharedUtil.cpp
+//  hifi
+//
+//  Created by Stephen Birarda on 2/22/13.
+//
+//
+
+#include "SharedUtil.h"
+
+double usecTimestamp(timeval *time) {
+    return (time->tv_sec * 1000000.0);
+}
+
+double usecTimestampNow() {
+    timeval now;
+    gettimeofday(&now, NULL);
+    return (now.tv_sec * 1000000.0);
+}

shared/src/SharedUtil.h

@@ -0,0 +1,18 @@
+//
+//  SharedUtil.h
+//  hifi
+//
+//  Created by Stephen Birarda on 2/22/13.
+//
+//
+
+#ifndef __hifi__SharedUtil__
+#define __hifi__SharedUtil__
+
+#include <iostream>
+#include <sys/time.h>
+
+double usecTimestamp(timeval *time);
+double usecTimestampNow();
+
+#endif /* defined(__hifi__SharedUtil__) */