Log

/********************************Log**********************************/
#define LOGFILESIZE 10000000
#define LOGPATH L"\\Program Files\\protect.log"
#define ENDFLAG ("LastLine\r\n")
#define BYTES_NUM_ENDFLAG (sizeof(ENDFLAG) - 1) 
#define STR_MAX_LEN   1024
char g_szLogTemp[50] = {0};
/********************************Log**********************************/

void PrintAutoSleepLog(LPCSTR szFormat)
{
    BYTE bZero[BYTES_NUM_ENDFLAG] = {0};
    try{

        char szBuffer[STR_MAX_LEN] = {0};
        UINT cbSize = sizeof(szBuffer);
        SYSTEMTIME st;
        GetLocalTime(&st);
        int nLogChars;
        if(strlen(g_szLogTemp)>0)
        {
            nLogChars=_snprintf(szBuffer, cbSize, "%d:%.2d:%.2d  %s %s", 
                st.wHour, st.wMinute, st.wSecond, g_szLogTemp,szFormat);
            g_szLogTemp[0] = '\0';
        }
        else                  
            nLogChars = _snprintf(szBuffer, cbSize, "%d:%.2d:%.2d  %s", st.wHour, st.wMinute, st.wSecond, szFormat);

        if(nLogChars<0)
        {
            szBuffer[cbSize-2] = '\r';
            szBuffer[cbSize-1] = '\n';
            nLogChars = cbSize - 1;
        }

        DWORD dwPoint        = 0;
        DWORD dwBuffsize     = 0;
        DWORD dwFilesize     = 0;

        HANDLE hC4Log = CreateFile(LOGPATH, GENERIC_READ|GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL,
            OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
        if(hC4Log != INVALID_HANDLE_VALUE)
        {

            dwFilesize = GetFileSize(hC4Log, NULL);
            if(dwFilesize != 0 && dwFilesize != 0xFFFFFFFF)
            {
                dwPoint = SetFilePointer(hC4Log, -4, 0, FILE_END);
                if(0xFFFFFFFF != dwPoint)
                {
                    ReadFile(hC4Log, &dwPoint, sizeof(DWORD), &dwBuffsize, 0);
                    dwPoint = SetFilePointer(hC4Log, dwPoint - BYTES_NUM_ENDFLAG, 0, FILE_BEGIN);
                }

                if(dwPoint > LOGFILESIZE)
                    dwPoint = SetFilePointer(hC4Log, 0, 0, FILE_BEGIN);

            }        

            strcat(szBuffer, ENDFLAG);

            long len = strlen(szBuffer);
            DWORD ltemp = 0;
            if(dwPoint + len > LOGFILESIZE)
            {
                WriteFile(hC4Log, bZero, BYTES_NUM_ENDFLAG, &ltemp, NULL);
                dwPoint = SetFilePointer(hC4Log, 0, 0, FILE_BEGIN);
            }

            WriteFile(hC4Log, szBuffer, len, &ltemp, NULL);

            dwPoint = SetFilePointer(hC4Log, 0, 0, FILE_CURRENT);
            if((dwPoint + 4) >= dwFilesize)
                SetFilePointer(hC4Log, dwPoint, 0, FILE_BEGIN);
            else
                SetFilePointer(hC4Log, -4, 0, FILE_END);
            WriteFile(hC4Log, &dwPoint, sizeof(DWORD), &ltemp, NULL);
            CloseHandle(hC4Log);
        }

    }
    catch(...)
    {
        NKDbgPrintfW(TEXT("Exception!!!!!!!!!!!!!!!!!\r\n"));
    }
}