checknetwork.cpp

funambol windows mobile plugin source code, the source code is taken from the funambol site

/*
 * Copyright (C) 2003-2007 Funambol, Inc
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY, TITLE, NONINFRINGEMENT or FITNESS FOR A PARTICULAR
 * PURPOSE.  See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 * 02111-1307  USA
 */

// checknet.cpp : test network status.
//
#include <winsock2.h>
#include <ws2tcpip.h>
#include <windows.h>
#include <tchar.h>
#include "base/util/utils.h"

struct in_addr BIN_IPV4_ADDR_LOOPBACK = {127, 0, 0, 1};
struct in6_addr BIN_IPV6_ADDR_LOOPBACK =   {   0x0, 0x0,
                                             0x0, 0x0,
                                             0x0, 0x0,
                                             0x0, 0x0,
                                             0x0, 0x0,
                                             0x0, 0x0,
                                             0x0, 0x0,
                                             0x0, 0x1 };
#define   MAX_LOCAL_NAME_LEN               64


static char localAddress[64] = "0.0.0.0";

static void Print(TCHAR *pFormat, ...) {
    va_list ArgList;
    TCHAR   Buffer[256];

    va_start (ArgList, pFormat);
    (void)wvsprintf (Buffer, pFormat, ArgList);

    va_end(ArgList);
}

//Function Prototypes
bool IsNetPresent();

const char* getLocalAddress()
{
    return localAddress;
}

void getIPAddress(wchar_t* address) {
    wchar_t* t = toWideChar(localAddress);
    wcscpy (address, t);
    delete [] t;
}

bool checkNetwork()
{
   WSADATA WSAData;

   WSAStartup(MAKEWORD(2,2), &WSAData);
   bool ret = IsNetPresent();
   WSACleanup();

   return ret;
}

//
// Determine if you have a IPv4 or IPv6 network address.
//
bool IsNetPresent()
{
    bool bFoundLocalAddr = false;
    char szAddrASCII[MAX_LOCAL_NAME_LEN];
    ADDRINFO AddrHints, *pAI, *pAddrInfo;

    //
    // Get the local host's name in ASCII text.
    //
    if(gethostname(szAddrASCII, MAX_LOCAL_NAME_LEN - 1))
    {

        return false;
    }

    //
    // To obtain a list of all the local
    // addresses, resolve the local name with getaddrinfo for all
    // protocol families.
    //

    memset(&AddrHints, 0, sizeof(AddrHints));
    AddrHints.ai_family = PF_UNSPEC;
    AddrHints.ai_flags = AI_PASSIVE;

    if(getaddrinfo(szAddrASCII, "10", &AddrHints, &pAddrInfo))
    {

        return false;
    }

    //
    // Search the addresses returned.
    // If any of them match the loopback address, then
    // are not connected to an outside network.
    //
    // Note: This will not tell you how many networks you
    // are connected to.  If one or more networks are present,
    // then the loopback addresses will not be included in the
    // list returned from getaddrinfo.
    //
    bFoundLocalAddr = true;
    for(pAI = pAddrInfo; pAI != NULL && bFoundLocalAddr; pAI = pAI->ai_next)
    {
        if(pAI->ai_family == PF_INET)
        {
            SOCKADDR_IN *addr = (SOCKADDR_IN *)(pAI->ai_addr);

            sprintf(localAddress, "%d.%d.%d.%d",
                    addr->sin_addr.S_un.S_un_b.s_b1,
                    addr->sin_addr.S_un.S_un_b.s_b2,
                    addr->sin_addr.S_un.S_un_b.s_b3,
                    addr->sin_addr.S_un.S_un_b.s_b4);


            if(memcmp(&(addr->sin_addr),
                &BIN_IPV4_ADDR_LOOPBACK,
                sizeof(BIN_IPV4_ADDR_LOOPBACK)) == 0)
                bFoundLocalAddr = false;
        }
        else if(pAI->ai_family == PF_INET6)
        {
            SOCKADDR_IN6 *addr = (SOCKADDR_IN6 *)(pAI->ai_addr);
            if(memcmp(&(addr->sin6_addr),
                &BIN_IPV6_ADDR_LOOPBACK,
                sizeof(BIN_IPV6_ADDR_LOOPBACK)) == 0)
                bFoundLocalAddr = false;
        }
    }

    freeaddrinfo(pAddrInfo);

    return bFoundLocalAddr;
}