I’m using WM_SOCKET. Server and client are running fine. But if I close the client and reopen it FD_READ is not responding only FD_CLOSE and FD_ACCEPT work fine. Please someone help me…
Server Code:
#include <winsock2.h>
#include <windows.h>
#pragma comment(lib,"ws2_32.lib")
#define IDC_EDIT_IN 101
#define IDC_EDIT_OUT 102
#define IDC_MAIN_BUTTON 103
#define WM_SOCKET 104
int nPort=5555;
HWND hEditIn=NULL;
HWND hEditOut=NULL;
SOCKET Socket=NULL;
char szHistory[10000];
sockaddr sockAddrClient;
LRESULT CALLBACK WinProc(HWND hWnd,UINT message,WPARAM wParam,LPARAM lParam);
int WINAPI WinMain(HINSTANCE hInst,HINSTANCE hPrevInst,LPSTR lpCmdLine,int nShowCmd)
{
WNDCLASSEX wClass;
ZeroMemory(&wClass,sizeof(WNDCLASSEX));
wClass.cbClsExtra=NULL;
wClass.cbSize=sizeof(WNDCLASSEX);
wClass.cbWndExtra=NULL;
wClass.hbrBackground=(HBRUSH)COLOR_WINDOW;
wClass.hCursor=LoadCursor(NULL,IDC_ARROW);
wClass.hIcon=NULL;
wClass.hIconSm=NULL;
wClass.hInstance=hInst;
wClass.lpfnWndProc=(WNDPROC)WinProc;
wClass.lpszClassName="Window Class";
wClass.lpszMenuName=NULL;
wClass.style=CS_HREDRAW|CS_VREDRAW;
if(!RegisterClassEx(&wClass))
{
int nResult=GetLastError();
MessageBox(NULL,
"Window class creation failed\r\nError code:",
"Window Class Failed",
MB_ICONERROR);
}
HWND hWnd=CreateWindowEx(NULL, "Window Class", "Winsock Async Server",
WS_OVERLAPPEDWINDOW, 200, 200, 640, 480, NULL, NULL, hInst,
NULL);
if(!hWnd)
{
int nResult=GetLastError();
MessageBox(NULL,
"Window creation failed\r\nError code:",
"Window Creation Failed",
MB_ICONERROR);
}
ShowWindow(hWnd,nShowCmd);
MSG msg;
ZeroMemory(&msg,sizeof(MSG));
while(GetMessage(&msg,NULL,0,0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return 0;
}
LRESULT CALLBACK WinProc(HWND hWnd,UINT msg,WPARAM wParam,LPARAM lParam)
{
switch(msg)
{
case WM_COMMAND:
switch(LOWORD(wParam))
{
case IDC_MAIN_BUTTON:
{
char szBuffer[1024];
ZeroMemory(szBuffer,sizeof(szBuffer));
SendMessage(hEditOut,
WM_GETTEXT,
sizeof(szBuffer),
reinterpret_cast<LPARAM>(szBuffer));
send(Socket,szBuffer,strlen(szBuffer),0);
SendMessage(hEditOut,WM_SETTEXT,NULL,(LPARAM)"");
}
break;
}
break;
case WM_CREATE:
{
ZeroMemory(szHistory,sizeof(szHistory));
// Create incoming message box
hEditIn=CreateWindowEx(WS_EX_CLIENTEDGE, "EDIT", "", WS_CHILD|WS_VISIBLE|ES_MULTILINE|ES_AUTOVSCROLL|ES_AUTOHSCROLL,
50, 120, 400, 200, hWnd, (HMENU)IDC_EDIT_IN,
GetModuleHandle(NULL),
NULL);
if(!hEditIn)
{
MessageBox(hWnd,
"Could not create incoming edit box.",
"Error",
MB_OK|MB_ICONERROR);
}
HGDIOBJ hfDefault=GetStockObject(DEFAULT_GUI_FONT);
SendMessage(hEditIn,
WM_SETFONT,
(WPARAM)hfDefault,
MAKELPARAM(FALSE,0));
SendMessage(hEditIn,
WM_SETTEXT,
NULL,
(LPARAM)"Waiting for client to connect...");
// Create outgoing message box
hEditOut=CreateWindowEx(WS_EX_CLIENTEDGE, "EDIT",
"", WS_CHILD|WS_VISIBLE|ES_MULTILINE|
ES_AUTOVSCROLL|ES_AUTOHSCROLL,
50, 50, 400, 60, hWnd,
(HMENU)IDC_EDIT_IN,
GetModuleHandle(NULL),
NULL);
if(!hEditOut)
{
MessageBox(hWnd,
"Could not create outgoing edit box.",
"Error",
MB_OK|MB_ICONERROR);
}
SendMessage(hEditOut,
WM_SETFONT,
(WPARAM)hfDefault,
MAKELPARAM(FALSE,0));
SendMessage(hEditOut,
WM_SETTEXT,
NULL,
(LPARAM)"Type message here...");
// Create a push button
HWND hWndButton=CreateWindow( "BUTTON",
"Send",
WS_TABSTOP|WS_VISIBLE|
WS_CHILD|BS_DEFPUSHBUTTON,
50, 330, 75, 23,
hWnd, (HMENU)IDC_MAIN_BUTTON,
GetModuleHandle(NULL),
NULL);
SendMessage(hWndButton,
WM_SETFONT,
(WPARAM)hfDefault,
MAKELPARAM(FALSE,0));
WSADATA WsaDat;
int nResult=WSAStartup(MAKEWORD(2,2),&WsaDat);
if(nResult!=0)
{
MessageBox(hWnd,
"Winsock initialization failed",
"Critical Error",
MB_ICONERROR);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
Socket=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
if(Socket==INVALID_SOCKET)
{
MessageBox(hWnd,
"Socket creation failed",
"Critical Error",
MB_ICONERROR);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
SOCKADDR_IN SockAddr;
SockAddr.sin_port=htons(nPort);
SockAddr.sin_family=AF_INET;
SockAddr.sin_addr.s_addr=htonl(INADDR_ANY);
if(bind(Socket,(LPSOCKADDR)&SockAddr,sizeof(SockAddr))==SOCKET_ERROR)
{
MessageBox(hWnd,"Unable to bind socket","Error",MB_OK);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
nResult=WSAAsyncSelect(Socket,
hWnd,
WM_SOCKET,
(FD_CLOSE|FD_ACCEPT|FD_READ));
if(nResult)
{
MessageBox(hWnd,
"WSAAsyncSelect failed",
"Critical Error",
MB_ICONERROR);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
if(listen(Socket,(1))==SOCKET_ERROR)
{
MessageBox(hWnd,
"Unable to listen!",
"Error",
MB_OK);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
}
break;
case WM_DESTROY:
{
PostQuitMessage(0);
shutdown(Socket,SD_BOTH);
closesocket(Socket);
WSACleanup();
return 0;
}
break;
case WM_SOCKET:
{
switch(WSAGETSELECTEVENT(lParam))
{
case FD_READ:
{
char szIncoming[1024];
ZeroMemory(szIncoming,sizeof(szIncoming));
int inDataLength=recv(Socket,
(char*)szIncoming,
sizeof(szIncoming)/sizeof(szIncoming[0]),
0);
strncat(szHistory,szIncoming,inDataLength);
strcat(szHistory,"\r\n");
SendMessage(hEditIn,
WM_SETTEXT,
sizeof(szIncoming)-1,
reinterpret_cast<LPARAM>(&szHistory));
}
break;
case FD_CLOSE:
{
MessageBox(hWnd,
"Client closed connection",
"Connection closed!",
MB_ICONINFORMATION|MB_OK); }
break;
case FD_ACCEPT:
{
int size=sizeof(sockaddr);
Socket=accept(wParam,&sockAddrClient,&size);
if (Socket==INVALID_SOCKET)
{
int nret = WSAGetLastError();
WSACleanup();
}
SendMessage(hEditIn,
WM_SETTEXT,
NULL,
(LPARAM)"Client connected!");
}
break;
}
}
}
return DefWindowProc(hWnd,msg,wParam,lParam);
}
Client Code:
#include <winsock2.h>
#include <windows.h>
#pragma comment(lib,"ws2_32.lib")
#define IDC_EDIT_IN 101
#define IDC_EDIT_OUT 102
#define IDC_MAIN_BUTTON 103
#define WM_SOCKET 104
char *szServer="localhost";
int nPort=5555;
HWND hEditIn=NULL;
HWND hEditOut=NULL;
SOCKET Socket=NULL;
char szHistory[10000];
LRESULT CALLBACK WinProc(HWND hWnd,UINT message,WPARAM wParam,LPARAM lParam);
int WINAPI WinMain(HINSTANCE hInst,HINSTANCE hPrevInst,LPSTR lpCmdLine,int nShowCmd)
{
WNDCLASSEX wClass;
ZeroMemory(&wClass,sizeof(WNDCLASSEX));
wClass.cbClsExtra=NULL;
wClass.cbSize=sizeof(WNDCLASSEX);
wClass.cbWndExtra=NULL;
wClass.hbrBackground=(HBRUSH)COLOR_WINDOW;
wClass.hCursor=LoadCursor(NULL,IDC_ARROW);
wClass.hIcon=NULL;
wClass.hIconSm=NULL;
wClass.hInstance=hInst;
wClass.lpfnWndProc=(WNDPROC)WinProc;
wClass.lpszClassName="Window Class";
wClass.lpszMenuName=NULL;
wClass.style=CS_HREDRAW|CS_VREDRAW;
if(!RegisterClassEx(&wClass))
{
int nResult=GetLastError();
MessageBox(NULL,
"Window class creation failed\r\nError code:",
"Window Class Failed",
MB_ICONERROR);
}
HWND hWnd=CreateWindowEx(NULL,
"Window Class",
"Windows Async Client",
WS_OVERLAPPEDWINDOW,
200,
200,
640,
480,
NULL,
NULL,
hInst,
NULL);
if(!hWnd)
{
int nResult=GetLastError();
MessageBox(NULL,
"Window creation failed\r\nError code:",
"Window Creation Failed",
MB_ICONERROR);
}
ShowWindow(hWnd,nShowCmd);
MSG msg;
ZeroMemory(&msg,sizeof(MSG));
while(GetMessage(&msg,NULL,0,0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return 0;
}
LRESULT CALLBACK WinProc(HWND hWnd,UINT msg,WPARAM wParam,LPARAM lParam)
{
switch(msg)
{
case WM_CREATE:
{
ZeroMemory(szHistory,sizeof(szHistory));
// Create incoming message box
hEditIn=CreateWindowEx(WS_EX_CLIENTEDGE,
"EDIT",
"",
WS_CHILD|WS_VISIBLE|ES_MULTILINE|
ES_AUTOVSCROLL|ES_AUTOHSCROLL,
50,
120,
400,
200,
hWnd,
(HMENU)IDC_EDIT_IN,
GetModuleHandle(NULL),
NULL);
if(!hEditIn)
{
MessageBox(hWnd,
"Could not create incoming edit box.",
"Error",
MB_OK|MB_ICONERROR);
}
HGDIOBJ hfDefault=GetStockObject(DEFAULT_GUI_FONT);
SendMessage(hEditIn,
WM_SETFONT,
(WPARAM)hfDefault,
MAKELPARAM(FALSE,0));
SendMessage(hEditIn,
WM_SETTEXT,
NULL,
(LPARAM)"Attempting to connect to server...");
// Create outgoing message box
hEditOut=CreateWindowEx(WS_EX_CLIENTEDGE,
"EDIT",
"",
WS_CHILD|WS_VISIBLE|ES_MULTILINE|
ES_AUTOVSCROLL|ES_AUTOHSCROLL,
50,
50,
400,
60,
hWnd,
(HMENU)IDC_EDIT_IN,
GetModuleHandle(NULL),
NULL);
if(!hEditOut)
{
MessageBox(hWnd,
"Could not create outgoing edit box.",
"Error",
MB_OK|MB_ICONERROR);
}
SendMessage(hEditOut,
WM_SETFONT,(WPARAM)hfDefault,
MAKELPARAM(FALSE,0));
SendMessage(hEditOut,
WM_SETTEXT,
NULL,
(LPARAM)"Type message here...");
// Create a push button
HWND hWndButton=CreateWindow(
"BUTTON",
"Send",
WS_TABSTOP|WS_VISIBLE|
WS_CHILD|BS_DEFPUSHBUTTON,
50,
330,
75,
23,
hWnd,
(HMENU)IDC_MAIN_BUTTON,
GetModuleHandle(NULL),
NULL);
SendMessage(hWndButton,
WM_SETFONT,
(WPARAM)hfDefault,
MAKELPARAM(FALSE,0));
// Set up Winsock
WSADATA WsaDat;
int nResult=WSAStartup(MAKEWORD(2,2),&WsaDat);
if(nResult!=0)
{
MessageBox(hWnd,
"Winsock initialization failed",
"Critical Error",
MB_ICONERROR);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
Socket=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
if(Socket==INVALID_SOCKET)
{
MessageBox(hWnd,
"Socket creation failed",
"Critical Error",
MB_ICONERROR);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
nResult=WSAAsyncSelect(Socket,hWnd,WM_SOCKET,(FD_CLOSE|FD_READ));
if(nResult)
{
MessageBox(hWnd,
"WSAAsyncSelect failed",
"Critical Error",
MB_ICONERROR);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
// Resolve IP address for hostname
struct hostent *host;
if((host=gethostbyname(szServer))==NULL)
{
MessageBox(hWnd,
"Unable to resolve host name",
"Critical Error",
MB_ICONERROR);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
// Set up our socket address structure
SOCKADDR_IN SockAddr;
SockAddr.sin_port=htons(nPort);
SockAddr.sin_family=AF_INET;
SockAddr.sin_addr.s_addr=*((unsigned long*)host->h_addr);
connect(Socket,(LPSOCKADDR)(&SockAddr),sizeof(SockAddr));
}
break;
case WM_COMMAND:
switch(LOWORD(wParam))
{
case IDC_MAIN_BUTTON:
{
char szBuffer[1024];
int test=sizeof(szBuffer);
ZeroMemory(szBuffer,sizeof(szBuffer));
SendMessage(hEditOut,
WM_GETTEXT,
sizeof(szBuffer),
reinterpret_cast<LPARAM>(szBuffer));
send(Socket,szBuffer,strlen(szBuffer),0);
SendMessage(hEditOut,WM_SETTEXT,NULL,(LPARAM)"");
}
break;
}
break;
case WM_DESTROY:
{
PostQuitMessage(0);
shutdown(Socket,SD_BOTH);
closesocket(Socket);
WSACleanup();
return 0;
}
break;
case WM_SOCKET:
{
if(WSAGETSELECTERROR(lParam))
{
MessageBox(hWnd,
"Connection to server failed",
"Error",
MB_OK|MB_ICONERROR);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
break;
}
switch(WSAGETSELECTEVENT(lParam))
{
case FD_READ:
{
char szIncoming[1024];
ZeroMemory(szIncoming,sizeof(szIncoming));
int inDataLength=recv(Socket,
(char*)szIncoming,
sizeof(szIncoming)/sizeof(szIncoming[0]),
0);
strncat(szHistory,szIncoming,inDataLength);
strcat(szHistory,"\r\n");
SendMessage(hEditIn,
WM_SETTEXT,
sizeof(szIncoming)-1,
reinterpret_cast<LPARAM>(&szHistory));
}
break;
case FD_CLOSE:
{
MessageBox(hWnd,
"Server closed connection",
"Connection closed!",
MB_ICONINFORMATION|MB_OK);
closesocket(Socket);
SendMessage(hWnd,WM_DESTROY,NULL,NULL);
}
break;
}
}
}
return DefWindowProc(hWnd,msg,wParam,lParam);
}
You have multiple problems. The first is that you do
WSAAsyncSelecton the passive listening socket forFD_READandFD_WRITEevents. A passive socket will not receive those events. The second is that you do not do anWSAAsyncSelecton the actual connected socket.There are other problems as well, the most serious that you only keep one variable for the sockets. This means you loose the "master" socket when you do accept, and that you can't have multiple connections (each new connection overwrites the socket variable). You also do not actually closing the socket on
FD_CLOSE(it's not done automatically), and there are probably more that I haven't spotted so far.