--- linuxsampler/trunk/src/network/lscpserver.cpp 2004/06/29 21:11:50 159 +++ linuxsampler/trunk/src/network/lscpserver.cpp 2004/07/03 20:08:07 170 @@ -22,17 +22,47 @@ #include "lscpserver.h" #include "lscpresultset.h" +#include "lscpevent.h" #include "../engines/gig/Engine.h" #include "../audiodriver/AudioOutputDeviceFactory.h" #include "../mididriver/MidiInputDeviceFactory.h" +/** + * Below are a few static members of the LSCPServer class. + * The big assumption here is that LSCPServer is going to remain a singleton. + * These members are used to support client connections. + * Class handles multiple connections at the same time using select() and non-blocking recv() + * Commands are processed by a single LSCPServer thread. + * Notifications are delivered either by the thread that originated them + * or (if the resultset is currently in progress) by the LSCPServer thread + * after the resultset was sent out. + * This makes sure that resultsets can not be interrupted by notifications. + * This also makes sure that the thread sending notification is not blocked + * by the LSCPServer thread. + */ +fd_set LSCPServer::fdSet; +int LSCPServer::currentSocket = -1; +std::vector LSCPServer::hSessions = std::vector(); +std::map LSCPServer::bufferedNotifies = std::map(); +std::map LSCPServer::bufferedCommands = std::map(); +std::map< LSCPEvent::event_t, std::list > LSCPServer::eventSubscriptions = std::map< LSCPEvent::event_t, std::list >(); +Mutex LSCPServer::NotifyMutex = Mutex(); +Mutex LSCPServer::NotifyBufferMutex = Mutex(); +Mutex LSCPServer::SubscriptionMutex = Mutex(); + LSCPServer::LSCPServer(Sampler* pSampler) : Thread(false, 0, -4) { this->pSampler = pSampler; + LSCPEvent::RegisterEvent(LSCPEvent::event_channels, "CHANNELS"); + LSCPEvent::RegisterEvent(LSCPEvent::event_voice_count, "VOICE_COUNT"); + LSCPEvent::RegisterEvent(LSCPEvent::event_stream_count, "STREAM_COUNT"); + LSCPEvent::RegisterEvent(LSCPEvent::event_buffer_fill, "BUFFER_FILL"); + LSCPEvent::RegisterEvent(LSCPEvent::event_info, "INFO"); + LSCPEvent::RegisterEvent(LSCPEvent::event_misc, "MISCELLANEOUS"); } int LSCPServer::Main() { - hSocket = socket(AF_INET, SOCK_STREAM, 0); + int hSocket = socket(AF_INET, SOCK_STREAM, 0); if (hSocket < 0) { std::cerr << "LSCPServer: Could not create server socket." << std::endl; //return -1; @@ -56,28 +86,209 @@ // now wait for client connections and handle their requests sockaddr_in client; int length = sizeof(client); + struct timeval tv; + tv.tv_sec = 30; + tv.tv_usec = 0; + FD_ZERO(&fdSet); + FD_SET(hSocket, &fdSet); + int maxSessions = hSocket; + + // Parser initialization + yyparse_param_t yyparse_param; + yyparse_param.pServer = this; + while (true) { - hSession = accept(hSocket, (sockaddr*) &client, (socklen_t*) &length); - if (hSession < 0) { - std::cerr << "LSCPServer: Client connection failed." << std::endl; - close(hSocket); - //return -1; - exit(EXIT_FAILURE); - } - - dmsg(1,("LSCPServer: Client connection established.\n")); - //send(hSession, "Welcome!\r\n", 10, 0); - - // Parser invocation - yyparse_param_t yyparse_param; - yyparse_param.pServer = this; - yylex_init(&yyparse_param.pScanner); - while (yyparse(&yyparse_param) == LSCP_SYNTAX_ERROR); // recall parser in case of syntax error - yylex_destroy(yyparse_param.pScanner); + fd_set selectSet = fdSet; + int retval = select(maxSessions+1, &selectSet, NULL, NULL, &tv); + if (retval == 0) + continue; //Nothing in 30 seconds, try again + if (retval == -1) { + std::cerr << "LSCPServer: Socket select error." << std::endl; + close(hSocket); + exit(EXIT_FAILURE); + } + + //Accept new connections now (if any) + if (FD_ISSET(hSocket, &selectSet)) { + int socket = accept(hSocket, (sockaddr*) &client, (socklen_t*) &length); + if (socket < 0) { + std::cerr << "LSCPServer: Client connection failed." << std::endl; + exit(EXIT_FAILURE); + } + + if (fcntl(socket, F_SETFL, O_NONBLOCK)) { + std::cerr << "LSCPServer: F_SETFL O_NONBLOCK failed." << std::endl; + exit(EXIT_FAILURE); + } + + hSessions.push_back(socket); + FD_SET(socket, &fdSet); + if (socket > maxSessions) + maxSessions = socket; + dmsg(1,("LSCPServer: Client connection established on socket:%d.\n", socket)); + LSCPServer::SendLSCPNotify(LSCPEvent(LSCPEvent::event_misc, "Client connection established on socket", socket)); + continue; //Maybe this was the only selected socket, better select again + } + + //Something was selected and it was not the hSocket, so it must be some command(s) coming. + for (std::vector::iterator iter = hSessions.begin(); iter != hSessions.end(); iter++) { + if (FD_ISSET(*iter, &selectSet)) { //Was it this socket? + if (GetLSCPCommand(iter)) { //Have we read the entire command? + dmsg(3,("LSCPServer: Got command on socket %d, calling parser.\n", currentSocket)); + yylex_init(&yyparse_param.pScanner); + currentSocket = *iter; //a hack + int result = yyparse(&yyparse_param); + currentSocket = -1; //continuation of a hack + dmsg(3,("LSCPServer: Done parsing on socket %d.\n", currentSocket)); + if (result == LSCP_QUIT) { //Was it a quit command by any chance? + CloseConnection(iter); + } + } + //socket may have been closed, iter may be invalid, get out of the loop for now. + //we'll be back if there is data. + break; + } + } - close(hSession); - dmsg(1,("LSCPServer: Client connection terminated.\n")); + //Now let's deliver late notifies (if any) + NotifyBufferMutex.Lock(); + for (std::map::iterator iterNotify = bufferedNotifies.begin(); iterNotify != bufferedNotifies.end(); iterNotify++) { + send(iterNotify->first, iterNotify->second.c_str(), iterNotify->second.size(), 0); + bufferedNotifies.erase(iterNotify); + } + NotifyBufferMutex.Unlock(); } + //It will never get here anyway + //yylex_destroy(yyparse_param.pScanner); +} + +void LSCPServer::CloseConnection( std::vector::iterator iter ) { + int socket = *iter; + dmsg(1,("LSCPServer: Client connection terminated on socket:%d.\n",socket)); + LSCPServer::SendLSCPNotify(LSCPEvent(LSCPEvent::event_misc, "Client connection terminated on socket", socket)); + hSessions.erase(iter); + FD_CLR(socket, &fdSet); + SubscriptionMutex.Lock(); //Must unsubscribe this socket from all events (if any) + for (std::map< LSCPEvent::event_t, std::list >::iterator iter = eventSubscriptions.begin(); iter != eventSubscriptions.end(); iter++) { + iter->second.remove(socket); + } + SubscriptionMutex.Unlock(); + NotifyMutex.Lock(); + bufferedCommands.erase(socket); + bufferedNotifies.erase(socket); + close(socket); + NotifyMutex.Unlock(); +} + +void LSCPServer::SendLSCPNotify( LSCPEvent event ) { + SubscriptionMutex.Lock(); + if (eventSubscriptions.count(event.GetType()) == 0) { + SubscriptionMutex.Unlock(); //Nobody is subscribed to this event + return; + } + std::list::iterator iter = eventSubscriptions[event.GetType()].begin(); + std::list::iterator end = eventSubscriptions[event.GetType()].end(); + String notify = event.Produce(); + + while (true) { + if (NotifyMutex.Trylock()) { + for(;iter != end; iter++) + send(*iter, notify.c_str(), notify.size(), 0); + NotifyMutex.Unlock(); + break; + } else { + if (NotifyBufferMutex.Trylock()) { + for(;iter != end; iter++) + bufferedNotifies[*iter] += notify; + NotifyBufferMutex.Unlock(); + break; + } + } + } + SubscriptionMutex.Unlock(); +} + +extern int GetLSCPCommand( void *buf, int max_size ) { + String command = LSCPServer::bufferedCommands[LSCPServer::currentSocket]; + if (command.size() == 0) { //Parser wants input but we have nothing. + strcpy((char*) buf, "\n"); //So give it an empty command + return 1; //to keep it happy. + } + + if (max_size < command.size()) { + std::cerr << "getLSCPCommand: Flex buffer too small, ignoring the command." << std::endl; + return 0; //This will never happen + } + + strcpy((char*) buf, command.c_str()); + LSCPServer::bufferedCommands.erase(LSCPServer::currentSocket); + return command.size(); +} + +/** + * Will be called to try to read the command from the socket + * If command is read, it will return true. Otherwise false is returned. + * In any case the received portion (complete or incomplete) is saved into bufferedCommand map. + */ +bool LSCPServer::GetLSCPCommand( std::vector::iterator iter ) { + int socket = *iter; + char c; + int i = 0; + while (true) { + int result = recv(socket, (void *)&c, 1, 0); //Read one character at a time for now + if (result == 0) { //socket was selected, so 0 here means client has closed the connection + CloseConnection(iter); + break; + } + if (result == 1) { + if (c == '\r') + continue; //Ignore CR + if (c == '\n') { + bufferedCommands[socket] += "\n"; + return true; //Complete command was read + } + bufferedCommands[socket] += c; + } + if (result == -1) { + if (errno == EAGAIN) //Would block, try again later. + return false; + switch(errno) { + case EBADF: + dmsg(2,("LSCPScanner: The argument s is an invalid descriptor.\n")); + break; + case ECONNREFUSED: + dmsg(2,("LSCPScanner: A remote host refused to allow the network connection (typically because it is not running the requested service).\n")); + break; + case ENOTCONN: + dmsg(2,("LSCPScanner: The socket is associated with a connection-oriented protocol and has not been connected (see connect(2) and accept(2)).\n")); + break; + case ENOTSOCK: + dmsg(2,("LSCPScanner: The argument s does not refer to a socket.\n")); + break; + case EAGAIN: + dmsg(2,("LSCPScanner: The socket is marked non-blocking and the receive operation would block, or a receive timeout had been set and the timeout expired before data was received.\n")); + break; + case EINTR: + dmsg(2,("LSCPScanner: The receive was interrupted by delivery of a signal before any data were available.\n")); + break; + case EFAULT: + dmsg(2,("LSCPScanner: The receive buffer pointer(s) point outside the process's address space.\n")); + break; + case EINVAL: + dmsg(2,("LSCPScanner: Invalid argument passed.\n")); + break; + case ENOMEM: + dmsg(2,("LSCPScanner: Could not allocate memory for recvmsg.\n")); + break; + default: + dmsg(2,("LSCPScanner: Unknown recv() error.\n")); + break; + } + CloseConnection(iter); + break; + } + } + return false; } /** @@ -88,7 +299,11 @@ */ void LSCPServer::AnswerClient(String ReturnMessage) { dmsg(2,("LSCPServer::AnswerClient(ReturnMessage=%s)", ReturnMessage.c_str())); - send(hSession, ReturnMessage.c_str(), ReturnMessage.size(), 0); + if (currentSocket != -1) { + NotifyMutex.Lock(); + send(currentSocket, ReturnMessage.c_str(), ReturnMessage.size(), 0); + NotifyMutex.Unlock(); + } } /** @@ -1005,18 +1220,26 @@ * Will be called by the parser to subscribe a client (frontend) on the * server for receiving event messages. */ -String LSCPServer::SubscribeNotification(event_t Event) { - dmsg(2,("LSCPServer: SubscribeNotification(Event=%d)\n", Event)); - return "ERR:0:Not implemented yet.\r\n"; +String LSCPServer::SubscribeNotification(LSCPEvent::event_t type) { + dmsg(2,("LSCPServer: SubscribeNotification(Event=%s)\n", LSCPEvent::Name(type).c_str())); + LSCPResultSet result; + SubscriptionMutex.Lock(); + eventSubscriptions[type].push_back(currentSocket); + SubscriptionMutex.Unlock(); + return result.Produce(); } /** * Will be called by the parser to unsubscribe a client on the server * for not receiving further event messages. */ -String LSCPServer::UnsubscribeNotification(event_t Event) { - dmsg(2,("LSCPServer: UnsubscribeNotification(Event=%d)\n", Event)); - return "ERR:0:Not implemented yet.\r\n"; +String LSCPServer::UnsubscribeNotification(LSCPEvent::event_t type) { + dmsg(2,("LSCPServer: UnsubscribeNotification(Event=%s)\n", LSCPEvent::Name(type).c_str())); + LSCPResultSet result; + SubscriptionMutex.Lock(); + eventSubscriptions[type].remove(currentSocket); + SubscriptionMutex.Unlock(); + return result.Produce(); }