session.hh

/*
    PowerMail versatile mail receiver
    Copyright (C) 2002  PowerDNS.COM BV

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
#ifndef SESSION_HH
#define SESSION_HH

#include <string>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <cerrno>
#include <arpa/inet.h>  

#include <sys/stat.h>
#include <unistd.h>
#include <netdb.h>
#include <iostream>
#include "ahuexception.hh"

class SessionException: public AhuException
{
public:
  SessionException(const string &reason) : AhuException(reason){}
};

class SessionTimeoutException: public SessionException
{
public:
  SessionTimeoutException(const string &reason) : SessionException(reason){}
};

//! The Session class represents a TCP/IP session, which can either be created or run on an existing socket
class Session
{
  class SessionBuffer
  {
  public:
    explicit SessionBuffer(unsigned int size=16000) : d_size(size), d_buffer(new char[d_size])
    {
    }
    SessionBuffer(const SessionBuffer &orig) : d_size(orig.d_size), d_buffer(new char[orig.d_size])
    {
      memcpy(d_buffer,orig.d_buffer,d_size);
    }
    ~SessionBuffer(){ 
      delete[] d_buffer; 
    }
    SessionBuffer& operator=(const SessionBuffer &rhs)
    {
      if(&rhs!=this) {
	delete[] d_buffer;
	d_size=rhs.d_size;

	d_buffer=new char[d_size];
	memcpy(d_buffer,rhs.d_buffer,d_size);
      }
      return *this;
    }
    operator char*() 
    {
      return d_buffer;
    }
  private:
    unsigned int d_size;
    char *d_buffer;
  };
public:
  void getLine(string &); //!< Read a line from the remote. Throws an exception in case of error or end of file
  bool haveLine(); //!< returns true if a line is available
  bool putLine(const string &s); //!< Write a line to the remote
  bool sendFile(int fd); //!< Send a file out
  int timeoutRead(int s,char *buf, size_t len);

  Session(int s, struct sockaddr_in r); //!< Start a session on an existing socket, and inform this class of the remotes name

  /** Create a session to a remote host and port. This function reads a timeout value from the ArgvMap class 
      and does a nonblocking connect to support this timeout. It should be noted that nonblocking connects 
      suffer from bad portability problems, so look here if you see weird problems on new platforms */
  Session(const string &remote, int port, int timeout=0); 
  Session(u_int32_t ip, int port, int timeout=0);

  
  ~Session();
  int getSocket(); //!< return the filedescriptor for layering violations
  string getRemote();
  u_int32_t getRemoteAddr();
  string getRemoteIP();
  void beVerbose();
  int close(); //!< close and disconnect the connection
  void setTimeout(unsigned int seconds);
private:
  void doConnect(u_int32_t ip, int port);
  Session(const Session &s); 
  Session&operator=(const Session&);
  bool d_verbose;
  SessionBuffer rdbuf;
  int d_bufsize;
  int rdoffset;
  int wroffset;
  int clisock;
  struct sockaddr_in remote;
  void init();
  int d_timeout;

};

//! The server class can be used to create listening servers
class Server
{
public:
  Server(int p, const string &localaddress=""); //!< port on which to listen
  Session* accept(); //!< Call accept() in an endless loop to accept new connections
private:
  int s;
  int port;
  int backlog;

  string d_localaddress;
};

class Exception
{
public:
  Exception(){reason="Unspecified";};
  Exception(string r){reason=r;};
  string reason;
};
int writen(int fd, const void* ptr, size_t size);
#endif /* SESSION_HH */