File content as of revision 0:1f77255a22f5:

/* Copyright (C) 2012 mbed.org, MIT License
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
 * and associated documentation files (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or
 * substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include "UDPSocket.h"
#include "bsd_socket.h"

#include <cstring>

using std::memset;

UDPSocket::UDPSocket() : m_sock(-1)
{
}

UDPSocket::~UDPSocket()
{
  close(); //Don't want to leak
}

int UDPSocket::bind(int port)
{
  int ret = init();
  if( ret < 0 ) 
  {
    return -1;
  }
  
  struct sockaddr_in localHost;
  std::memset(&localHost, 0, sizeof(localHost));
 
  localHost.sin_family = AF_INET;
  localHost.sin_port = htons(port);
  localHost.sin_addr.s_addr = INADDR_ANY;
  
  ret = ::bind(m_sock, (const struct sockaddr *)&localHost, sizeof(localHost));
  if (ret < 0)
  {
    close();
    return -1;
  }

  return 0;
}

// -1 if unsuccessful, else number of bytes written
int UDPSocket::sendTo(uint8_t* data, int length, char* host, int port, int timeout)
{
  if( m_sock < 0 )
  {
    return -1;
  }
  
  struct sockaddr_in remoteHost;
 
  //Populate m_remoteHost
  std::memset(&remoteHost, 0, sizeof(struct sockaddr_in));

  //Resolve DNS address or populate hard-coded IP address
  struct hostent *server = ::gethostbyname(host);
  if(server == NULL)
  {
    return -1; //Could not resolve address
  }
  std::memcpy((char*)&remoteHost.sin_addr.s_addr, (char*)server->h_addr_list[0], server->h_length);

  remoteHost.sin_family = AF_INET;
  remoteHost.sin_port = htons(port);

  size_t writtenLen = 0;
  struct timeval t_val; //t_val will be decremented on each call to select()
  t_val.tv_sec = timeout / 1000;
  t_val.tv_usec = (timeout - (t_val.tv_sec * 1000)) * 1000;
  while(writtenLen < length)
  {
    //Wait for socket to be writeable
    //Creating FS set
    fd_set socksSet;
    FD_ZERO(&socksSet);
    FD_SET(m_sock, &socksSet);

    int ret = ::select(FD_SETSIZE, NULL, &socksSet, NULL, &t_val);
    if(ret <= 0 || !FD_ISSET(m_sock, &socksSet))
    {
      return writtenLen; //Timeout -- FIXME should we return -1 or writtenLength ?
    }

    ret = ::sendto(m_sock, data + writtenLen, length - writtenLen, 0, (const struct sockaddr *)&remoteHost, sizeof(remoteHost));
    if( ret > 0)
    {
      writtenLen += ret;
      continue;
    }
    else if( ret == 0 )
    {
      return writtenLen; //Connection was closed by server -- FIXME how do we signal that the connection was closed ?
    }
    else
    {
      return -1; //Connnection error
    }
  }
  
  return writtenLen;
}

// -1 if unsuccessful, else number of bytes received
int UDPSocket::receiveFrom(uint8_t* data, int length, char** host, int* port, int timeout)
{
  if( m_sock < 0 )
  {
    return -1;
  }

  struct sockaddr_in remoteHost;
 
  //Populate m_remoteHost
  std::memset(&remoteHost, 0, sizeof(struct sockaddr_in));
  
  socklen_t remoteHostLen = sizeof(remoteHost);

  size_t readLen = 0;
  struct timeval t_val; //t_val will be decremented on each call to select()
  t_val.tv_sec = timeout / 1000;
  t_val.tv_usec = (timeout - (t_val.tv_sec * 1000)) * 1000;
  
  //No loop here as we don't want to mix packets from different sources
  do
  {
    //Wait for socket to be readable
    //Creating FS set
    fd_set socksSet;
    FD_ZERO(&socksSet);
    FD_SET(m_sock, &socksSet);
    int ret = ::select(FD_SETSIZE, &socksSet, NULL, NULL, &t_val);
    if(ret <= 0 || !FD_ISSET(m_sock, &socksSet))
    {
      break; //Timeout -- FIXME should we return -1 or writtenLength ?
    }
    
    ret = ::recvfrom(m_sock, data + readLen, length - readLen, 0, (struct sockaddr*)&remoteHost, &remoteHostLen);
    if( ret > 0)
    {
      readLen += ret;
    }
    else if( ret == 0 )
    {
      //Connection was closed by server -- FIXME how do we signal that the connection was closed ?
      //Continue and populate address
    }
    else
    {
      return -1; //Connection error
    }
  } while(0);
  
  static char hostBuf[16];
  inet_ntoa_r(remoteHost.sin_addr, hostBuf, sizeof(hostBuf));
  
  *host = hostBuf;
  *port = ntohs(remoteHost.sin_port);
  
  return readLen;
}

int UDPSocket::close()
{
  if( m_sock < 0 )
  {
    return -1;
  }

  ::close(m_sock);
  m_sock = -1;
  
  return 0;
}

int UDPSocket::init()
{
  if( m_sock != -1 )
  {
    return -1;
  }
  m_sock = ::socket(AF_INET, SOCK_DGRAM, 0); //UDP socket
  if (m_sock < 0)
  {
    return -1; //Could not create socket (Out of memory / available descriptors)
  }
  return 0;
}