Sockets.cpp

/*
   Copyright (c) 2011, Chris Pearce

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   - Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.

   - Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.

   - Neither the name of Chris Pearce nor the names of its
   contributors may be used to endorse or promote products derived from
   this software without specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
   PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE ORGANISATION OR
   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>

#include <iostream>

#include "Sockets.h"
#include "Utils.h"

#ifdef _WIN32

#include <winsock2.h>
#include <ws2tcpip.h>

#pragma comment(lib, "Ws2_32.lib")

class Win32Socket : public Socket {
public:
  virtual ~Win32Socket();
  Socket* Accept();
  Win32Socket(SOCKET aSocket);
  void Close();
  int Send(const char* aBuf, int aSize);
  int Receive(char* aBuf, int aSize);

  static WSADATA sWsaData;
};

WSADATA Win32Socket::sWsaData = {0};

Win32Socket::Win32Socket(SOCKET aSocket)
  : Socket((int)aSocket)
{ }

Win32Socket::~Win32Socket()
{
  Close();
}

Socket* Socket::Open(int aPort) {
  // Init a server port.
  struct addrinfo *addr = NULL, *ptr = NULL, hints;

  ZeroMemory(&hints, sizeof (hints));
  hints.ai_family = AF_INET;
  hints.ai_socktype = SOCK_STREAM;
  hints.ai_protocol = IPPROTO_TCP;
  hints.ai_flags = AI_PASSIVE;

  // Resolve the local address and port to be used by the server
  string port = ToString(aPort);
  int res = getaddrinfo(NULL, port.c_str(), &hints, &addr);
  if (res != 0) {
    cerr << "getaddrinfo failed: " << res << std::endl;
    return 0;
  }

  SOCKET serverSocket = INVALID_SOCKET;
  // Create a SOCKET for the server to listen for client connections
  serverSocket = socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);

  if (serverSocket == INVALID_SOCKET) {
    cerr << "Error at socket(): " << WSAGetLastError() << std::endl;
    freeaddrinfo(addr);
    return 0;
  }

  // Setup the TCP listening socket
  res = bind( serverSocket, addr->ai_addr, (int)addr->ai_addrlen);
  if (res == SOCKET_ERROR) {
    cerr << "bind failed: " << WSAGetLastError() << std::endl;
    freeaddrinfo(addr);
    closesocket(serverSocket);
    return 0;
  }

  // Address info is no longer needed, we've bound the socket.
  freeaddrinfo(addr);

  if ( listen( serverSocket, SOMAXCONN ) == SOCKET_ERROR ) {
    cerr << "Listen failed with error: " << WSAGetLastError() << std::endl;
    closesocket(serverSocket);
    return 0;
  }

  return new Win32Socket(serverSocket);
}

Socket* Win32Socket::Accept() {
  SOCKET client = accept(mSocket, NULL, NULL);
  if (client == INVALID_SOCKET) {
    cerr << "accept failed: " << WSAGetLastError() << std::endl;
    closesocket(mSocket);
    return 0;
  }
  return new Win32Socket(client);
}

void Win32Socket::Close() {
  if (mSocket != INVALID_SOCKET) {
    closesocket(mSocket);
    mSocket = (int)INVALID_SOCKET;
  }
}

int Win32Socket::Receive(char* aBuf, int aSize) {
  memset(aBuf, 0, aSize);
  int r = recv(mSocket, aBuf, aSize, 0);
  if (r < 0) {
    cerr << "recv failed: " << WSAGetLastError() << std::endl;
  }
  return r;
}

int Win32Socket::Send(const char* aBuf, int aSize) {
  return send(mSocket, aBuf, aSize, 0);
}

int Socket::Init() {
  // Initialize Winsock
  int err = WSAStartup(MAKEWORD(2,2), &Win32Socket::sWsaData);
  if (err) {
    cerr << "WSAStartup failed: " << err << std::endl;
    return 1;
  }
  return 0;
}

int Socket::Shutdown() {
  WSACleanup();
  return 0;
}

#else

#include <unistd.h>
#include <netinet/in.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <errno.h>

#define SOCKET_ERROR -1

class UnixSocket : public Socket {
public:
  virtual ~UnixSocket();
  Socket* Accept();
  UnixSocket(int aSocket);
  void Close();
  int Send(const char* aBuf, int aSize);
  int Receive(char* aBuf, int aSize);
};

Socket* Socket::Open(int aPort) {
  int sockfd;
  int flags = 1;
  struct sockaddr_in serv_addr;
  sockfd = socket(AF_INET, SOCK_STREAM, 0);
  if (sockfd < 0) {
    perror("ERROR opening socket");
    return 0;
  }

  if(setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &flags, sizeof(int))) {
    perror("Can't set SO_REUSEADDR.");
    return 0;
  }

  bzero((char *) &serv_addr, sizeof(serv_addr));
  serv_addr.sin_family = AF_INET;
  serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
  serv_addr.sin_port = htons(aPort);
  if (bind(sockfd,
           (struct sockaddr *) &serv_addr,
           sizeof(serv_addr)) < 0)
  {
    perror("ERROR on binding");
    return 0;
  }
  listen(sockfd,5);

  return new UnixSocket(sockfd);
}

UnixSocket::UnixSocket(int aSocket)
  : Socket(aSocket)
{
}

UnixSocket::~UnixSocket() {
  Close();
}

Socket* UnixSocket::Accept() {
  socklen_t clilen;
  struct sockaddr_in cli_addr;
  clilen = sizeof(cli_addr);

  if (!WaitForRead(500)) {
    return 0;
  }

  int client = accept(mSocket, 
                      (struct sockaddr *) &cli_addr, 
                      &clilen);
  if (client < 0)  {
    perror("ERROR on accept");
    close(mSocket);
    return 0;
  }
  return new UnixSocket(client);
}

void UnixSocket::Close() {
  if (mSocket != 0) {
    if (close(mSocket)) {
      perror("Could not close socket properly.");
      exit(1);
    }
    mSocket = 0;
  }
}

int UnixSocket::Receive(char* aBuf, int aSize) {
  memset(aBuf, 0, aSize);
  int r = read(mSocket, aBuf, aSize);
  if (r < 0) {
    fprintf(stderr, "Receive failed\n");
  }
  return r;
}

int UnixSocket::Send(const char* aBuf, int aSize) {
  return write(mSocket, aBuf, aSize);
}

int Socket::Init() {
  return 0;
}

int Socket::Shutdown() {
  return 0;
}

#endif

bool Socket::WaitForRead(unsigned timeout) {
  fd_set socks;
  FD_ZERO(&socks);
  FD_SET((unsigned)mSocket, &socks);

  struct timeval to;
  to.tv_sec = 0;
  to.tv_usec = timeout;
  
  return select(mSocket + 1, &socks, 0, 0, &to) > 0;
}

string Socket::GetIP() const {
  char buf[1024];
  if (gethostname(buf, sizeof(buf)) == SOCKET_ERROR) {
    return "Unknown";
  }

  struct hostent *host = gethostbyname(buf);
  if(host == NULL) {
    return "Unknown";
  }

  char* localIP;
  localIP = inet_ntoa(*(struct in_addr *)*host->h_addr_list);
  return string(localIP);
}