Colony

/** 

 * @file ColonetServer.cpp

 *

 * @brief colonet_server - primary server application for Colonet

 *

 * @author Jason Knichel

 * @author Eugene Marinelli

 * @date 10/31/06

 */

#include <arpa/inet.h>

#include <fcntl.h>

#include <errno.h>

#include <netinet/in.h>

#include <string.h>

#include <sys/select.h>

#include <sys/socket.h>

#include <colonet_wireless.h>

#include "includes/ColonetServer.h"

#include "includes/ConnectionPool.h"

#include "includes/wirelessMessageHandler.h"

#include "includes/options.h"

#include "includes/Log.h"

#define LISTEN_BACKLOG 5

#define LOG_BUFFER_LENGTH 128

ConnectionPool * connection_pool;

/**

 * @brief Default constructor for ColonetServer

 */

ColonetServer::ColonetServer(): logger("logFile.txt") {

  listen_socket = 0;

}

/**

 * @brief Destructor for ColonetServer

 */

ColonetServer::~ColonetServer() {

}

/**

 * @brief Initializes the various elements needed for the server to run

 *

 * @param argc The number of command line arguments passed to the program

 * @param argv The command line arguments passed to the program

 *

 * @return 0 on success, negative error code on failure

 */

int ColonetServer::initialize_server(int argc, char * argv[]) {

  printf("Initializing Server...\n");

  parseCmdLine(argc, argv);

  if (initialize_connection(optionsG.listen_port) < 0) {

    return -1;

  }

  if (initialize_wireless() < 0) {

    fprintf(stderr, "%s: initWireless failed\n", __FUNCTION__);

    return -1;

  }

  return 0;

}

/**

 * @brief Starts the server listening on the socket that was opened for listening

 *

 * @return 0 on success, negative error code on failure

 */

int ColonetServer::start_listening() {

  if (listen(listen_socket, LISTEN_BACKLOG) < 0) {

    logger.log_error("\t\nThere was an error telling the socket to "

                     "listen for connections from clients.  Terminating Server...\n");

    return -1;

  }

  return 0;

}

/**

 * @brief Starts the server running (starts an infinite loop)

 */

int ColonetServer::run_server() {

  connection_pool.set_listen_socket_in_ready_set(listen_socket);

  //TODO: why is all of this in that if statement and not just conn_pool.maxfd = listen_socket ?

  if (listen_socket > connection_pool.get_max_file_descriptor()) {

    connection_pool.set_max_file_descriptor(listen_socket);

    int accept_socket = 0;

    struct sockaddr_in client_addr;

    socklen_t client_addr_size = sizeof(client_addr);

    logger.log_message("Server initialized.  About to start listening for connections");

    while(1) {

      connection_pool.perform_select(listen_socket);

      //either no descriptors are ready or there was an error

      if (connection_pool.get_number_clients_ready() <= 0) {

        continue;

      }

      if (connection_pool.is_socket_ready_to_read(listen_socket)) {

        printf("Something is trying to connect...\n");

        if ((accept_socket = accept(listen_socket, (struct sockaddr*) &client_addr, &client_addr_size)) < 0) {

          if (errno == EMFILE) {

            printf("\tWhen attempting to accept a connection, "

                   "reached the per process limit of file descriptors."

                   "  Dropping the new connection.\n");

            continue;

          } else {

            printf("\tThere was an error when attempting to accept a connection");

          }

          continue;

        }

        char log_buffer[LOG_BUFFER_LENGTH];

        snprintf(log_buffer, LOG_BUFFER_LENGTH, "Client at address %s attempting to connect.", 

                 inet_ntoa(client_addr.sin_addr));

        logger.log_string(LOG_TYPE_CONNECT, log_buffer);

        if (connection_pool.add_client(accept_socket) < 0) {

          printf("\tThere was an error when trying to add a client to the connection pool.");

          continue;

        }

        snprintf(log_buffer, LOG_BUFFER_LENGTH, "Client at address %s successfully added to connection pool.", 

                 inet_ntoa(client_addr.sin_addr));

        logger.log_string(LOG_TYPE_CONNECT, log_buffer);

      }

      if (connection_pool.check_clients() < 0) {

        printf("\tThere was an error trying to update the clients.");

        continue;

      }

    }

  }

  return 0;

}

int ColonetServer::process_received_wireless_message(unsigned char type, short source, int dest,

                                                     unsigned char * data, int len) {

  if (type == COLONET_RESPONSE) {

    printf("response\n");

    char buffer[WRITE_BUFFER_SIZE];

    int value = (int)(data[0]);

    snprintf(buffer, WRITE_BUFFER_SIZE, "%d\n", value);

    int buflen = strlen(buffer);

    if (connection_pool.write_to_client(dest, buffer, buflen)

        == ERROR_INVALID_CLIENT_ID) {

      printf("The robot wanted to pass the data to a client not in the "

             "pool.\n");

      return -1;

    }

    printf("Put data in write buffer for client.\n");

  } else {

    printf("not a response\n");

    return -1;

  }

  return 0;

}

/**

 * @brief Initializes the wireless

 *

 * @return 0 on success, negative error code on error

 */

int ColonetServer::initialize_wireless() {

  char* log_filename = NULL;

  if (optionsG.logging_enabled) {

    log_filename = optionsG.log_filename;

  }

  /*

    colonet_wl_init(optionsG.wireless_port, wirelessMessageHandler,

    log_filename);

    if (!colonet_wl_run_listener_thread()) {

    fprintf(stderr, "%s: colonet_wl_run_listener_thread failed.\n",

    __FUNCTION__);

    return -1;

    }

  */

  return 0;

}

/**

 * @brief Initialize a connection to listen on

 *

 * @port The port to try to open to listen on

 *

 * @return 0 on success, negative error code on error

 */

int ColonetServer::initialize_connection(int port) {

  printf("Initializing connection that will be used to listen for " 

         "clients...\n");

  int options = 1;

  struct sockaddr_in my_address;

  //get a socket fd

  if ((listen_socket = socket(AF_INET, SOCK_STREAM, 0)) < 0) {

    printf("\tThere was an error creating a socket\n");

    return -1;

  }

  //set up the address struct

  memset(&my_address,'\0',sizeof(my_address));

  my_address.sin_family = AF_INET;

  my_address.sin_addr.s_addr = htonl(INADDR_ANY);

  my_address.sin_port = htons(port);

  setsockopt(listen_socket, SOL_SOCKET, SO_REUSEADDR, &options, sizeof(options));

  //get the current socket options

  if ((options = fcntl(listen_socket, F_GETFL)) < 0) {

    printf("\tThere was an error getting the socket options.\n");

    return -1;

  }

  //set the socket to non blocking

  options = (options | O_NONBLOCK);

  if (fcntl(listen_socket, F_SETFL, options) < 0) {

    printf("\tThere was an error setting the socket to be non blocking.\n");

    return -1;

  }

  //bind the socket to listen on the specified port

  if (bind(listen_socket, (struct sockaddr *) &my_address, sizeof(my_address)) < 0) {

    printf("\tThere was an error binding the socket\n");

    return -1;

  }

  return 0;

}

/**

 * @brief The main function of the server

 *

 * @param argc The number of command line arguments passed to the program

 * @param argv The command line arguments passed to the program

 *

 * @return 0 on success, negative error code on error

 */

ColonetServer colonet_server;

int main(int argc, char** argv) {

  if (colonet_server.initialize_server(argc, argv) < 0) {

    printf("\t\nThere was an error initializing the server. "

           "Terminating server...\n");

    return -1;

  }

  if (colonet_server.start_listening() < 0) {

    return -1;

  }

  colonet_server.run_server();

  return 0;

}