Compiler: undefined reference

[pedrosacosta]

Hi,

I've a socket example that I'm trying to compile, but I get the following error:

Compiler: Default compiler
Building Makefile: "D:\cpp_workspace\Makefile.win"
Executing  make...
make.exe -f "D:\cpp_workspace\Makefile.win" all
g++.exe -D__DEBUG__ Translator/socket.o Translator/socketClient.o Translator/main.o  -o "Translator.exe" -L"D:/Dev-Cpp/lib" -L"C:/WINNT/system32" -mwindows  -g3 

Translator/socket.o(.text+0x124):socket.cpp: undefined reference to `WSAStartup@8'
Translator/socket.o(.text+0x169):socket.cpp: undefined reference to `WSACleanup@0'
Translator/socket.o(.text+0x1aa):socket.cpp: undefined reference to `socket@12'
Translator/socket.o(.text+0x23e):socket.cpp: undefined reference to `socket@12'

Translator/socket.o(.text+0x4dc):socket.cpp: undefined reference to `closesocket@4'
Translator/socket.o(.text+0x56f):socket.cpp: undefined reference to `ioctlsocket@12'
Translator/socket.o(.text+0x5d3):socket.cpp: undefined reference to `recv@16'
Translator/socket.o(.text+0x784):socket.cpp: undefined reference to `recv@16'
Translator/socket.o(.text+0x941):socket.cpp: undefined reference to `send@16'
Translator/socket.o(.text+0x989):socket.cpp: undefined reference to `send@16'
Translator/socketClient.o(.text+0x7b):socketClient.cpp: undefined reference to `gethostbyname@4'
Translator/socketClient.o(.text+0x10a):socketClient.cpp: undefined reference to `htons@4'
Translator/socketClient.o(.text+0x159):socketClient.cpp: undefined reference to `connect@12'
Translator/socketClient.o(.text+0x169):socketClient.cpp: undefined reference to `WSAGetLastError@0'
Translator/socketClient.o(.text+0x2f9):socketClient.cpp: undefined reference to `gethostbyname@4' 

Here is the code:

socketClient.h

#include "socket.h"

class SocketClient : public Socket {
	  public:
  SocketClient(const std::string& host, int port);
};

socketClient.cpp

#include "socket.h"
#include "socketClient.h"

SocketClient::SocketClient(const std::string& host, int port) : Socket() {
  std::string error;

  hostent *he;
  if ((he = gethostbyname(host.c_str())) == 0) {
    error = strerror(errno);
    throw error;
  }

  sockaddr_in addr;
  addr.sin_family = AF_INET;
  addr.sin_port = htons(port);
  addr.sin_addr = *((in_addr *)he->h_addr);
  memset(&(addr.sin_zero), 0, 8); 

  if (::connect(s_, (sockaddr *) &addr, sizeof(sockaddr))) {
    error = strerror(WSAGetLastError());
    throw error;
  }
}

socket.h

#ifndef SOCKET_H
#define SOCKET_H

#include <winsock2.h>

#include <string>

enum TypeSocket {BlockingSocket, NonBlockingSocket};

class Socket {
public:

  virtual ~Socket();
  Socket(const Socket&);
  Socket& operator=(Socket&);

  std::string receiveLine();
  std::string receiveBytes();

  void close();

  // The parameter of SendLine is not a const reference
  // because SendLine modifes the std::string passed.
  void sendLine (std::string);

  // The parameter of SendBytes is a const reference
  // because SendBytes does not modify the std::string passed 
  // (in contrast to SendLine).
  void sendBytes(const std::string&);

protected:
/*
  friend class socketServer;
  friend class socketSelect;
*/

  Socket(SOCKET s);
  Socket();


  SOCKET s_;

  int* refCounter_;

private:
  static void start();
  static void end();
  static int  nofSockets_;
};

/*
class SocketClient : public Socket {
public:
  SocketClient(const std::string& host, int port);
};
*/

/*
class SocketServer : public Socket {
public:
  SocketServer(int port, int connections, TypeSocket type=BlockingSocket);

  Socket* Accept();
};
*/
// http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winsock/wsapiref_2tiq.asp
/*
class SocketSelect {
  public:
    SocketSelect(Socket const * const s1, Socket const * const s2=NULL, TypeSocket type=BlockingSocket);

    bool Readable(Socket const * const s);

  private:
    fd_set fds_;
};
*/
#endif

socket.cpp

#include "socket.h"
#include <iostream>

int Socket::nofSockets_= 0;

void Socket::start() {
  if (!nofSockets_) {
    WSADATA info;
    if (WSAStartup(MAKEWORD(2,0), &info)) {
      throw "Could not start WSA";
    }
  }
  ++nofSockets_;
}

void Socket::end() {
  WSACleanup();
}

Socket::Socket() : s_(0) {
  start();
  // UDP: use SOCK_DGRAM instead of SOCK_STREAM
  s_ = socket(AF_INET,SOCK_STREAM,0);

  if (s_ == INVALID_SOCKET) {
    throw "INVALID_SOCKET";
  }

  refCounter_ = new int(1);
}

Socket::Socket(SOCKET s) : s_(s) {
  start();
  refCounter_ = new int(1);
};

// Clear socket
Socket::~Socket() {
  if (! --(*refCounter_)) {
    close();
    delete refCounter_;
  }

  --nofSockets_;
  if (!nofSockets_) end();
}

// Create socket
Socket::Socket(const Socket& o) {
  refCounter_=o.refCounter_;
  (*refCounter_)++;
  s_         =o.s_;

  nofSockets_++;
}

// Set socket
Socket& Socket::operator=(Socket& o) {
  (*o.refCounter_)++;

  refCounter_=o.refCounter_;
  s_         =o.s_;

  nofSockets_++;

  return *this;
}

// Close connection
void Socket::close() {
  closesocket(s_);
}

// Get bytes
std::string Socket::receiveBytes() {
  std::string ret;
  char buf[1024];
 
  while (1) {
    u_long arg = 0;
    if (ioctlsocket(s_, FIONREAD, &arg) != 0)
      break;

    if (arg == 0)
      break;

    if (arg > 1024) arg = 1024;

    int rv = recv (s_, buf, arg, 0);
    if (rv <= 0) break;

    std::string t;

    t.assign (buf, rv);
    ret += t;
  }
 
  return ret;
}

// Get a string line
std::string Socket::receiveLine() {
  std::string ret;
  while (1) {
    char r;

    switch(recv(s_, &r, 1, 0)) {
      case 0: // not connected anymore;
              // ... but last line sent
              // might not end in \n,
              // so return ret anyway.
        return ret;
      case -1:
        return "";
    }

    ret += r;
    if (r == '\n')  return ret;
  }
}

// Send line
void Socket::sendLine(std::string s) {
  s += '\n';
  send(s_,s.c_str(),s.length(),0);
}

// Send bytes
void Socket::sendBytes(const std::string& s) {
  send(s_,s.c_str(),s.length(),0);
}

main.cpp

#include "socket.h"
#include "socketClient.h"
#include <iostream>

using namespace std;

int main() {

  try {
    SocketClient s("www.google.com", 80);
	Socket* sk;
	sk = dynamic_cast<Socket*>(&s);
	cout << typeid(sk).name() << endl;

/*	
   ((Socket*) &s).sendLine("GET / HTTP/1.0");
    s.sendLine("Host: www.google.com");
    s.sendLine("");

    while (1) {
      string l = s.receiveLine();
      if (l.empty()) break;
      cout << l;
      cout.flush();
    }
*/
  } 
  catch (const char* s) {
    cerr << s << endl;
  } 
  catch (std::string s) {
    cerr << s << endl;
  } 
  catch (...) {
    cerr << "unhandled exception\n";
  }

  return 0;
}

I think that the problem it's because the compiler can't find:

#include <winsock2.h> 

but I explicit make a referece to the directory C:/WINNT/system32 where it exists the Ws2_32.dll file.

What's wrong?

Thanks,
PSC

[Null]

Probably your compiler can't find the winsock library. If you're using gcc then add -lwsock32 command option