ServiceBase.h

/****************************** Module Header ******************************\
* Module Name:  ServiceBase.h
* Project:      service-base
* Copyright (c) Microsoft Corporation.
* Copyright (c) Tromgy (tromgy@yahoo.com)
*
* Provides a base class for a service that will exist as part of a service
* application. CServiceBase must be derived from when creating a new service
* class.
*
* This source is subject to the Microsoft Public License.
* See http://www.microsoft.com/en-us/openness/resources/licenses.aspx#MPL.
* All other rights reserved.
*
* THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
* EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
\***************************************************************************/

#pragma once

#include <windows.h>

class CServiceBase
{
  public:

    // Register the executable for a service with the Service Control Manager
    // (SCM). After you call Run(ServiceBase), the SCM issues a Start command,
    // which results in a call to the OnStart method in the service. This
    // method blocks until the service has stopped.
    static BOOL Run(CServiceBase &service);

    // Service object constructor. The optional parameters (fCanStop,
    // fCanShutdown and fCanPauseContinue) allow you to specify whether the
    // service can be stopped, paused and continued, or be notified when
    // system shutdown occurs.
    CServiceBase(PCWSTR pszServiceName,
                 BOOL fCanStop = TRUE,
                 BOOL fCanShutdown = TRUE,
                 BOOL fCanPauseContinue = FALSE,
                 DWORD dwErrorEventId = 0,
                 WORD wErrorCategoryId = 0);

    // Service object destructor.
    virtual ~CServiceBase(void);

    // A command line to be passed to the service when it runs
    void SetCommandLine(int argc, PWSTR argv[])
    {
        m_argc = argc;
        m_argv = argv;
    }

    // Stop the service.
    void Stop();

  protected:

    // When implemented in a derived class, executes when a Start command is
    // sent to the service by the SCM or when the operating system starts
    // (for a service that starts automatically). Specifies actions to take
    // when the service starts.
    virtual void OnStart(DWORD dwArgc, PWSTR *pszArgv);

    // When implemented in a derived class, executes when a Stop command is
    // sent to the service by the SCM. Specifies actions to take when a
    // service stops running.
    virtual void OnStop();

    // When implemented in a derived class, executes when a Pause command is
    // sent to the service by the SCM. Specifies actions to take when a
    // service pauses.
    virtual void OnPause();

    // When implemented in a derived class, OnContinue runs when a Continue
    // command is sent to the service by the SCM. Specifies actions to take
    // when a service resumes normal functioning after being paused.
    virtual void OnContinue();

    // When implemented in a derived class, executes when the system is
    // shutting down. Specifies what should occur immediately prior to the
    // system shutting down.
    virtual void OnShutdown();

    // Set the service status and report the status to the SCM.
    void SetServiceStatus(DWORD dwCurrentState,
                          DWORD dwWin32ExitCode = NO_ERROR,
                          DWORD dwWaitHint = 0);

    // Log a message to the Application event log.
    virtual void WriteLogEntry(PCWSTR pszMessage, WORD wType, DWORD dwEventId = 0, WORD wCategory = 0);

    // Log an error message to the Application event log.
    virtual void WriteErrorLogEntry(PCWSTR pszFunction,
                                    DWORD dwError = GetLastError());

    // Entry point for the service. It registers the handler function for the
    // service and starts the service.
    static void WINAPI ServiceMain(DWORD dwArgc, LPWSTR *lpszArgv);

    // The function is called by the SCM whenever a control code is sent to
    // the service.
    static void WINAPI ServiceCtrlHandler(DWORD dwCtrl);

    // Start the service.
    void Start(DWORD dwArgc, PWSTR *pszArgv);

    // Pause the service.
    void Pause();

    // Resume the service after being paused.
    void Continue();

    // Execute when the system is shutting down.
    void Shutdown();

    // The singleton service instance.
    static CServiceBase *s_service;

    // The name of the service
    PCWSTR m_name;

    // Command line for the service
    int m_argc;
    PWSTR* m_argv;

    // The status of the service
    SERVICE_STATUS m_status;

    // The service status handle
    SERVICE_STATUS_HANDLE m_statusHandle;

    // This is used for error logging into Windows Event Log
    DWORD m_dwErrorEventId;
    WORD m_wErrorCategoryId;
};