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A Wrapper Class for NT Services

August 1998/A Wrapper Class for NT Services/Listing 5

Listing 5: Implementation file for MyService class

#include <windows.h>
#include <winsock.h>
#include <stdlib.h>
#include <stdio.h>
#include <process.h>

#include "myserve.h"
#include "tapplog.h"

static const char szRegBasePath[] = 

    const char*              srvname, 
    LPHANDLER_FUNCTION       fpSrvCtrl
    :    NTService( srvname, fpSrvMain, fpSrvCtrl )
    mStat.dwControlsAccepted = 
#ifdef LOGGING
    m_log = new TAppLog( m_name, LOG_ALL );

MyService::~MyService( void )
#ifdef LOGGING
    delete m_log;

DWORD MyService::Init( DWORD ac, LPTSTR *av )
    LogEvent( LOG_INFORM, "MyServe init..." );
    mhMailslot = CreateMailslot( 
        "\\\\.\\mailslot\\myserve", //== mailslot name
        4096,                       //== maximum message size
        200,                        //== milliseconds to timeout
        NULL                        //== security attributes
    if( mhMailslot == INVALID_HANDLE_VALUE ){
        Error( __LINE__ );
        return false;

    mhOutfile = CreateFile( 
        "c:\\temp\\outfile.txt",    //== filename
        GENERIC_WRITE,              //== access type
        FILE_SHARE_READ,            //== share mode
        NULL,                       //== security mode
        CREATE_ALWAYS,              //== always creates the file
        FILE_ATTRIBUTE_NORMAL,      //== sets file attributes
        NULL                        //== template file

    if( mhOutfile == INVALID_HANDLE_VALUE ){
        Error( __LINE__ );
        return false;

    LogEvent( LOG_INFORM, "MyServe starting..." );
    return NO_ERROR;

int MyService::Run( void )
    DWORD   msg_sz = 0;
    DWORD   bytes_read = 0; 
    DWORD   bytes_written = 0;
    BOOL    aok; 
    char    buff[4096];
    m_running = true;            //== changed by OnStop()

    while( m_running ){
        aok = GetMailslotInfo(
            mhMailslot,         // mailslot handle 
            NULL,               // no maximum message size 
            &msg_sz,            // size of next message 
            NULL,               // number of messages 
            NULL                // no read time-out 
        if( !aok )
            Error( __LINE__ );
        if(aok && (msg_sz != MAILSLOT_NO_MESSAGE)) 
            if( ReadFile( mhMailslot, buff, msg_sz, 
                    &bytes_read, NULL ))
                WriteFile( mhOutfile, buff, bytes_read, 
                    &bytes_written, NULL);
    CloseHandle( mhOutfile );
    CloseHandle( mhMailslot );
    return NO_ERROR; 

void MyService::OnStop( void )
    m_running = false;

#ifdef LOGGING
void MyService::LogEvent( LOG_LEVEL level, char* argstr, ... )
    va_list vl;
    va_start( vl, argstr );
    if( m_log )
        m_log->LogEventVL( level, argstr, vl );

void MyService::InstallAid( void )
    //== install the logging information
    if( m_log )

void MyService::Error( long line = 0 )
    DWORD errval = GetLastError();
    LPVOID lpMsgBuf;

                                                   // language
        (LPTSTR) &lpMsgBuf,
    LogEvent( LOG_ERROR, "line (%d): %s", line, lpMsgBuf );
    LocalFree( lpMsgBuf );
//End of File

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