A Wrapper Class for NT Services

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[] = 
    "SYSTEM\\CurrentControlSet\\Services\\";

MyService::MyService( 
    const char*              srvname, 
    LPSERVICE_MAIN_FUNCTION  fpSrvMain, 
    LPHANDLER_FUNCTION       fpSrvCtrl
    )
    :    NTService( srvname, fpSrvMain, fpSrvCtrl )
{
    mStat.dwControlsAccepted = 
        SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
#ifdef LOGGING
    m_log = new TAppLog( m_name, LOG_ALL );
#endif
}

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

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 )
        m_log->Install();
}

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

    FormatMessage( 
        FORMAT_MESSAGE_ALLOCATE_BUFFER | 
        FORMAT_MESSAGE_FROM_SYSTEM | 
        FORMAT_MESSAGE_IGNORE_INSERTS,
        NULL,
        GetLastError(),
        MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default 
                                                   // language
        (LPTSTR) &lpMsgBuf,
        0,
        NULL 
    );
    LogEvent( LOG_ERROR, "line (%d): %s", line, lpMsgBuf );
    LocalFree( lpMsgBuf );
}
#endif
//End of File