C / C++ / MFC

luderjane wrote:

I use blocking mode at most of time, except creating a new connection to server.

I turn socket into non-blocking mode first, then use select() to check the socket before turning back.

Webchat in Europe (only 4K)

#include <stdio.h>
#include <tchar.h>
#include <Winsock2.h>

typedef struct ServerInfo {
    char sIP[32];
    int iPort;
    DWORD dwTimeout;
    BOOL bPrintable;
} ServerInfo, *pServerInfo;

DWORD WINAPI OpenThreadProc(void* lpParam);
void BlockingOpen(pServerInfo pServer);
void NonBlockingOpen(pServerInfo pServer);

int _tmain(int argc, _TCHAR* argv[])
{
    int iNumOfURServer = 0;
    char sIP[32];
    int iPort = 80;
    DWORD dwTimeout = 5000;
    
    printf("Number of unreachable server: ");
    scanf("%d", &iNumOfURServer);
    printf("Reachable server IP: ");
    scanf("%s", sIP);
    printf("Reachable server port: ");
    scanf("%d", &iPort);
    printf("Timeout(in millisecond, 0 indicates blocking mode): ");
    scanf("%u", &dwTimeout);

    WSADATA wsaData;
    WORD version = MAKEWORD(2,2);
    WSAStartup(version, &wsaData);

    pServerInfo ServerArray = new ServerInfo[iNumOfURServer+1];
    char sURIP[32];

    for (int i = 0; i < iNumOfURServer; i++)
    {
        sprintf(sURIP, "192.168.1.1%02d", i);
        strcpy_s(ServerArray[i].sIP, sURIP);
        ServerArray[i].iPort = 3456;
        ServerArray[i].dwTimeout = dwTimeout;
        ServerArray[i].bPrintable = FALSE;

        CreateThread(NULL, 0, OpenThreadProc, &ServerArray[i], 0, NULL);
    }

    strcpy_s(ServerArray[iNumOfURServer].sIP, sIP);
    ServerArray[iNumOfURServer].iPort = iPort;
    ServerArray[iNumOfURServer].dwTimeout = dwTimeout;
    ServerArray[iNumOfURServer].bPrintable = TRUE;
    CreateThread(NULL, 0, OpenThreadProc, &ServerArray[iNumOfURServer], 0, NULL);

    scanf("%d", &iPort);

    return 0;
}

DWORD WINAPI OpenThreadProc(void* lpParam)
{
    pServerInfo pServer = (pServerInfo)lpParam;
    
    while (true)
    {
        if (pServer->dwTimeout == 0)
        {
            BlockingOpen(pServer);
        } 
        else
        {
            NonBlockingOpen(pServer);
        }
        
        Sleep(1000);
    }

    return 0;
}

void BlockingOpen(pServerInfo pServer)
{
    SOCKET theSocket;
    int nRet;

    //
    // Store information about the server
    //
    LPHOSTENT lpHostEntry;

    lpHostEntry = gethostbyname(pServer->sIP);		// Specifying server by its name
    if (lpHostEntry == NULL) {
       return;
    }

    //
    // Create the socket
    //
    theSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

    if (theSocket == INVALID_SOCKET) {
        return;
    }

    //
    // Use SOCKADDR_IN to fill in address information
    //
    SOCKADDR_IN saServer;

    saServer.sin_family = AF_INET;
    saServer.sin_addr = *((LPIN_ADDR)*lpHostEntry->h_addr_list);
    // ^ Address of the server being inserted into the address field
    saServer.sin_port = htons(pServer->iPort);

    //
    // Connect to the server
    //
    DWORD dwStartTime = GetTickCount();
    nRet = connect(theSocket,
        (LPSOCKADDR)&saServer,		// Server address
        sizeof(struct sockaddr));	// Length of address structure
    if (pServer->bPrintable)
    {
        if (nRet == SOCKET_ERROR) 
        {
            printf("%s:%d blocking open failed takes %d ms\n", pServer->sIP, pServer->iPort, 
                      GetTickCount()-dwStartTime);
        }
        else
        {
            printf("%s:%d blocking open successful takes %d ms\n", pServer->sIP, pServer->iPort,  
                      GetTickCount()-dwStartTime);
        }
    }

    closesocket(theSocket);
}

void NonBlockingOpen(pServerInfo pServer)
{
    SOCKET theSocket;
    int nRet;
    //
    // Store information about the server
    //
    LPHOSTENT lpHostEntry;

    lpHostEntry = gethostbyname(pServer->sIP);		// Specifying server by its name
    if (lpHostEntry == NULL) {
        return;
    }

    //
    // Create the socket
    //
    theSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

    if (theSocket == INVALID_SOCKET) {
        return;
    }

    // Set socket to non-blocking mode
    //
    unsigned long ul = 1;
    nRet = ioctlsocket(theSocket, FIONBIO, (unsigned long*)&ul);
    if (nRet == SOCKET_ERROR) {
        closesocket(theSocket);
        return;
    }

    // Use SOCKADDR_IN to fill in address information
    //
    SOCKADDR_IN saServer;

    saServer.sin_family = AF_INET;
    saServer.sin_addr = *((LPIN_ADDR)*lpHostEntry->h_addr_list);
    // ^ Address of the server being inserted into the address field
    saServer.sin_port = htons(pServer->iPort);

    // Connect to the server
    //
    nRet = connect(theSocket,
        (LPSOCKADDR)&saServer,		// Server address
        sizeof(struct sockaddr));	// Length of address structure

    if (nRet == SOCKET_ERROR && WSAGetLastError() != WSAEWOULDBLOCK) {
        closesocket(theSocket);
        return;
    }

    struct timeval timeout;
    fd_set r;

    FD_ZERO(&r);
    FD_SET(theSocket, &r);
    timeout.tv_sec = pServer->dwTimeout / 1000;
    timeout.tv_usec = (pServer->dwTimeout % 1000) * 1000;
    DWORD dwStartTime = GetTickCount();
    nRet = select(0, 0, &r, 0, &timeout);
    if (pServer->bPrintable)
    {
        if ( nRet <= 0 ) 
        {
            printf("%s:%d non-blocking open failed takes %d ms\n", pServer->sIP, pServer->iPort, 
                      GetTickCount()-dwStartTime);
        }
        else
        {
            printf("%s:%d non-blocking open successful takes %d ms\n", pServer->sIP, 
                      pServer->iPort, GetTickCount()-dwStartTime);
        }
    }

    closesocket(theSocket);
}

if (!CDocument::OnNewDocument())
    return FALSE;

int iMenu = pMenu->GetMenuItemCount() - 2;

// If this assertion fails, your menu bar does not follow the guidelines
// so you will have to override this function and call CreateClient
// appropriately or use the MFC V2 MDI functionality.
ASSERT(iMenu >= 0);

ratheeshnair123 wrote:

else
{
m_treeCtrl.Select(htItem, TVGN_DROPHILITE);
}

Paulraj G wrote:

I have added the library name in project setting.

1. Add the .lib files as linker input (additional dependecies).
2. Make Visual Studio aware of the folder(s) wherein such library files are (add the folders in the VC++ directories list).
3. Include the appropriate headers in your source files.

Paulraj G wrote:

but the library files are not working...