Reputation: 103
I am trying to bind a tcp socket on windows and when expecting an integer back from the function I get a compile error. I am not a c++ programmer and usually do not work on Windows so I am having trouble tracking this issue down. One thing I did notice was that if I did not include the winsock header file all of the other functions I use dealing with sockets such as send, recv, accept and connect all raise compile errors but one was not raised for the bind function. This leads me to believe that I am some how pulling in a different bind function then I am expecting.
The list of included header files for the entire application
#include <fstream>
#include <string>
#include <ctime>
#include <mutex>
#include <stdio.h>
#include <strsafe.h>
#include <map>
#include <iterator>
#include <process.h>
#include <queue>
#include <iostream>
#include <winsock.h>
The included library's are
#pragma comment(lib, "Ws2_32.lib")
#pragma comment(lib, "User32.lib")
And the class that is trying to use the bind function is
//implement an interface for udp and tcp socket classes to implement
class Socket
{
public:
virtual void sendm(const char *buf) = 0;
virtual int recvm(char *buf) = 0;
struct hostent *phe; /* pointer to host information entry */
struct servent *pse; /* pointer to service information entry */
struct protoent *ppe; /* pointer to protocol information entry */
struct sockaddr_in sin; /* an Internet endpoint address */
int type, status; /* socket descriptor and socket type */
SOCKET s; /* socket */
};
class TCPSocket : public Socket {
public:
TCPSocket(const char *host, const char *service, bool master_socket){
initialize_socket(host, service, master_socket);
}
~TCPSocket(void);
SOCKET initialize_socket(const char *host, const char *service, bool master_socket) {
cout << "host: " << host << endl;
cout << "service: " << service << endl;
char* transport = "tcp";
int qlen = 10;
int portbase = 0;
memset(&sin, 0, sizeof(sin));
sin.sin_family = AF_INET;
if (pse = getservbyname(service, transport) ) {
sin.sin_port = htons(ntohs((u_short)pse->s_port) + portbase);
}
else if ((sin.sin_port = htons((u_short)atoi(service))) == 0)
{
cout << "can't get " << service << " service" << endl;
exit(1);
}
/* Map protocol name to protocol number */
if ( (ppe = getprotobyname(transport)) == 0) {
cout << "Can't get \"" << transport << "\" protocol entry "<< endl;
exit(1);
}
/* Map host name to IP address, allowing for dotted decimal */
if (master_socket) {
sin.sin_addr.s_addr = htonl( INADDR_ANY );
}
else {
if ( phe = gethostbyname(host) ) {
memcpy(&sin.sin_addr, phe->h_addr, phe->h_length);
}
else if ( (sin.sin_addr.s_addr = inet_addr(host)) == INADDR_NONE) {
cout << "Can't get \"" << host << "\" IP address "<< endl;
exit(1);
}
}
type = SOCK_STREAM;
s = socket(AF_INET, type, ppe->p_proto);
if (s == INVALID_SOCKET) {
cout << "Socket Error: " << GetLastError() << endl;
exit(1);
}
if (master_socket) {
status = bind(s, (sockaddr *)&sin, sizeof(sin));
/* if (status != 0) { */
/* cout << "Bind Error: " << service << " port: " << GetLastError(); */
/* } */
status = listen(s, qlen);
if (status != 0) {
cout << "can't listen on " << service << " port: " << GetLastError();
exit(1);
}
} else {
int status = connect(s, (struct sockaddr*)&sin, sizeof(sin));
if ( status != 0 ) {
cout << "could not connect" << endl;
exit(1);
}
}
return s;
}
SOCKET acceptSocket() {
return accept(s, (struct sockaddr*)&sin, (int*)sizeof(sin));
}
void sendm(const char *buf) {
send(s, buf, strlen(buf), 0);
}
int recvm(char *buf) {
return recv(s, buf, BUFFER_SIZE, 0);
}
};
The documentation on bind on msdn says this function returns an int.
The compile error I get when attempting to compile is
error C2440: '=' : cannot convert from 'std::_Bind<_Forced,_Ret,_Fun,_V0_t,_V1_t,_V2_t,_V3_t,_V4_t,_V5_t,<unnamed-symbol>>' to 'int'
with
[
_Forced=false,
_Ret=void,
_Fun=SOCKET &,
_V0_t=sockaddr *,
_V1_t=unsigned int,
_V2_t=std::_Nil,
_V3_t=std::_Nil,
_V4_t=std::_Nil,
_V5_t=std::_Nil,
<unnamed-symbol>=std::_Nil
]
No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called
I am working with Windows 8 running on a VM in VirtualBox. I am using Visual Studios 2012 command developer command line to compile my code. Any suggestions as to why bind is not working as expected would be very much appreciated.
Upvotes: 0
Views: 2541
Reputation: 1233
when using <mutex>
and have "using namespace std"
use ::bind()
instead of bind()
Upvotes: 2
Reputation: 52385
This leads me to believe that I am some how pulling in a different bind function then I am expecting.
Yes, you are pulling in std::bind. If you look inside <mutex>
it has this line #include <functional>
which includes std::bind
.
You probably have a using namespace std;
somewhere which makes all the names from the std
namespace visible.
Also, the bind you want is in Winsock2.h
, and I didn't see an #include
for it.
Please read Why is 'using namespace std;' considered a bad practice in C++?. I would recommend removing any using directives (which is probably the cause of this issue) and fully qualify everything.
Upvotes: 2