Netzwerk - Computer Pingen

[WARDUKE]

Kann mir jemand sagen, wie ich in C einen Computer pingen kann. Aber natürlich nicht
mit
system ("Ping 192.168.0.33") ;
Danke

[class CMarcus]

Hm, da geistert eine Lösung durch's Netz, die sich auf der leider veralteten ICMP.dll abstützt... ist eine Klasse für C++, aber sollte kein Problem in C sein.

Header

#ifndef CPING_H
#define CPING_H

typedef struct tagIPINFO
{
    u_char Ttl;                // Time To Live
    u_char Tos;                // Type Of Service
    u_char IPFlags;            // IP flags
    u_char OptSize;            // Size of options data
    u_char FAR *Options;    // Options data buffer
}IPINFO;

typedef IPINFO* PIPINFO;

typedef struct tagICMPECHO
{
    u_long Source;            // Source address
    u_long Status;            // IP status
    u_long RTTime;            // Round trip time in milliseconds
    u_short DataSize;        // Reply data size
    u_short Reserved;        // Unknown
    void FAR *pData;        // Reply data buffer
    IPINFO    ipInfo;            // Reply options
}ICMPECHO;

typedef ICMPECHO* PICMPECHO;

class CPing
{
public:
    CPing();
    ~CPing();
    BOOL Ping(char* strHost);
private:
    // ICMP.DLL Export Function Pointers
    HANDLE (WINAPI *pIcmpCreateFile)(VOID);
    BOOL (WINAPI *pIcmpCloseHandle)(HANDLE);
    DWORD (WINAPI *pIcmpSendEcho)
        (HANDLE,DWORD,LPVOID,WORD,PIPINFO,LPVOID,DWORD,DWORD);
    HANDLE hndlIcmp;            // LoadLibrary() handle to ICMP.DLL
    BOOL bValid; // if it doesn't construct properly, it won't be valid
};

#endif

und dann die Implementation:

Code:

#include "CPing.h"

CPing::CPing()
{
    bValid = FALSE;
    WSADATA wsaData;            // WSADATA
    int nRet;                    // General use return code

    // Dynamically load the ICMP.DLL
    hndlIcmp = LoadLibrary("ICMP.DLL");
    if (hndlIcmp == NULL)
    {
        ::MessageBox(NULL, "Could not load ICMP.DLL", "Error:", MB_OK);
        return;
    }
    // Retrieve ICMP function pointers
    pIcmpCreateFile  = (HANDLE (WINAPI *)(void))
        GetProcAddress((HMODULE)hndlIcmp,"IcmpCreateFile");
    pIcmpCloseHandle = (BOOL (WINAPI *)(HANDLE))
        GetProcAddress((HMODULE)hndlIcmp,"IcmpCloseHandle");
    pIcmpSendEcho = (DWORD (WINAPI *)
        (HANDLE,DWORD,LPVOID,WORD,PIPINFO,LPVOID,DWORD,DWORD))
        GetProcAddress((HMODULE)hndlIcmp,"IcmpSendEcho");
    // Check all the function pointers
    if (pIcmpCreateFile == NULL        | | 
        pIcmpCloseHandle == NULL    | |
        pIcmpSendEcho == NULL)
    {
        ::MessageBox(NULL, "Error loading ICMP.DLL", "Error:", MB_OK);
        FreeLibrary((HMODULE)hndlIcmp);
        return;
    }

    // Init WinSock
    nRet = WSAStartup(0x0101, &wsaData );
    if (nRet)
    {
        ::MessageBox(NULL, "WSAStartup() error:", "Error:", MB_OK);
        WSACleanup();
        FreeLibrary((HMODULE)hndlIcmp);
        return;
    }
    // Check WinSock version
    if (0x0101 != wsaData.wVersion)
    {
        ::MessageBox(NULL, "No WinSock version 1.1 support found", "Error:", MB_OK);
        WSACleanup();
        FreeLibrary((HMODULE)hndlIcmp);
        return;
    }
    bValid = TRUE;
}

CPing::~CPing()
{
    WSACleanup();
    FreeLibrary((HMODULE)hndlIcmp);
}

int CPing::Ping(char* strHost)
{
    struct in_addr iaDest;        // Internet address structure
    LPHOSTENT pHost;            // Pointer to host entry structure
    DWORD *dwAddress;            // IP Address
    IPINFO ipInfo;                // IP Options structure
    ICMPECHO icmpEcho;            // ICMP Echo reply buffer
    HANDLE hndlFile;            // Handle for IcmpCreateFile()

    if(!bValid)
    {
        return FALSE;
    }

    // Lookup destination
    // Use inet_addr() to determine if we're dealing with a name
    // or an address
    iaDest.s_addr = inet_addr(strHost);
    if (iaDest.s_addr == INADDR_NONE)
        pHost = gethostbyname(strHost);
    else
        pHost = gethostbyaddr((const char *)&iaDest, 
                        sizeof(struct in_addr), AF_INET);
    if (pHost == NULL)
    {
        return FALSE;
    }

    // Copy the IP address
    dwAddress = (DWORD *)(*pHost->h_addr_list);

    // Get an ICMP echo request handle        
    hndlFile = pIcmpCreateFile();

    // Set some reasonable default values
    ipInfo.Ttl = 255;
    ipInfo.Tos = 0;
    ipInfo.IPFlags = 0;
    ipInfo.OptSize = 0;
    ipInfo.Options = NULL;
    icmpEcho.Status = 0;
    // Reqest an ICMP echo
    pIcmpSendEcho(
        hndlFile,        // Handle from IcmpCreateFile()
        *dwAddress,        // Destination IP address
        NULL,            // Pointer to buffer to send
        0,                // Size of buffer in bytes
        &ipInfo,        // Request options
        &icmpEcho,        // Reply buffer
        sizeof(struct tagICMPECHO),
        1000);            // Time to wait in milliseconds
    // Print the results
    iaDest.s_addr = icmpEcho.Source;
    if (icmpEcho.Status)
    {
        return FALSE;
    }

    // Close the echo request file handle
    pIcmpCloseHandle(hndlFile);
    return TRUE;
}

Aufruf:

CPing Ping;
int nTime;
nTime = Ping.Ping("www.yahoo.com");
nTime = Ping.Ping("192.168.1.1");

liefert dann die Zeit in Millisekunden.

Für modernere Lösungen via Winsock2 mußt Du mal bei www.codeguru.com suchen.

[ 09.07.2001: Beitrag editiert von: class CMarcus ]