/* A skeleton for writing an NT/2K service */
/* Author :- Nishant S */
/* EMail :- nish@inapp.com */

#include <windows.h>
#include <winsvc.h>

void ServiceMain(DWORD argc, LPTSTR *argv); 
void ServiceCtrlHandler(DWORD nControlCode);
BOOL UpdateServiceStatus(DWORD dwCurrentState, DWORD dwWin32ExitCode,
					 DWORD dwServiceSpecificExitCode, DWORD dwCheckPoint,
					 DWORD dwWaitHint);
BOOL StartServiceThread();
DWORD ServiceExecutionThread(LPDWORD param);
HANDLE hServiceThread;
void KillService();

char *strServiceName = "NishFirstService";
SERVICE_STATUS_HANDLE nServiceStatusHandle; 
HANDLE killServiceEvent;
BOOL nServiceRunning;
DWORD nServiceCurrentStatus;

void main(int argc, char* argv[])
{
	SERVICE_TABLE_ENTRY servicetable[]=
	{
		{strServiceName,(LPSERVICE_MAIN_FUNCTION)ServiceMain},
		{NULL,NULL}
	};
	BOOL success;
	success=StartServiceCtrlDispatcher(servicetable);
	if(!success)
	{
		//error occured
	}
}

void ServiceMain(DWORD argc, LPTSTR *argv)
{
	BOOL success;
	nServiceStatusHandle=RegisterServiceCtrlHandler(strServiceName,
		(LPHANDLER_FUNCTION)ServiceCtrlHandler);
	if(!nServiceStatusHandle)
	{
		return;
	}
	success=UpdateServiceStatus(SERVICE_START_PENDING,NO_ERROR,0,1,3000);
	if(!success)
	{
		return;
	}
	killServiceEvent=CreateEvent(0,TRUE,FALSE,0);
	if(killServiceEvent==NULL)
	{
		return;
	}
	success=UpdateServiceStatus(SERVICE_START_PENDING,NO_ERROR,0,2,1000);
	if(!success)
	{
		return;
	}
	success=StartServiceThread();
	if(!success)
	{
		return;
	}
	nServiceCurrentStatus=SERVICE_RUNNING;
	success=UpdateServiceStatus(SERVICE_RUNNING,NO_ERROR,0,0,0);
	if(!success)
	{
		return;
	}
	WaitForSingleObject(killServiceEvent,INFINITE);
	CloseHandle(killServiceEvent);
}



BOOL UpdateServiceStatus(DWORD dwCurrentState, DWORD dwWin32ExitCode,
					 DWORD dwServiceSpecificExitCode, DWORD dwCheckPoint,
					 DWORD dwWaitHint)
{
	BOOL success;
	SERVICE_STATUS nServiceStatus;
	nServiceStatus.dwServiceType=SERVICE_WIN32_OWN_PROCESS;
	nServiceStatus.dwCurrentState=dwCurrentState;
	if(dwCurrentState==SERVICE_START_PENDING)
	{
		nServiceStatus.dwControlsAccepted=0;
	}
	else
	{
		nServiceStatus.dwControlsAccepted=SERVICE_ACCEPT_STOP			
			|SERVICE_ACCEPT_SHUTDOWN;
	}
	if(dwServiceSpecificExitCode==0)
	{
		nServiceStatus.dwWin32ExitCode=dwWin32ExitCode;
	}
	else
	{
		nServiceStatus.dwWin32ExitCode=ERROR_SERVICE_SPECIFIC_ERROR;
	}
	nServiceStatus.dwServiceSpecificExitCode=dwServiceSpecificExitCode;
	nServiceStatus.dwCheckPoint=dwCheckPoint;
	nServiceStatus.dwWaitHint=dwWaitHint;

	success=SetServiceStatus(nServiceStatusHandle,&nServiceStatus);

	if(!success)
	{
		KillService();
		return success;
	}
	else
		return success;
}

BOOL StartServiceThread()
{	
	DWORD id;
	hServiceThread=CreateThread(0,0,
		(LPTHREAD_START_ROUTINE)ServiceExecutionThread,
		0,0,&id);
	if(hServiceThread==0)
	{
		return false;
	}
	else
	{
		nServiceRunning=true;
		return true;
	}
}

DWORD ServiceExecutionThread(LPDWORD param)
{
	while(nServiceRunning)
	{		
		Beep(450,150);
		Sleep(4000);
	}
	return 0;
}

void KillService()
{
	nServiceRunning=false;
	SetEvent(killServiceEvent);
	UpdateServiceStatus(SERVICE_STOPPED,NO_ERROR,0,0,0);
}

void ServiceCtrlHandler(DWORD nControlCode)
{
	BOOL success;
	switch(nControlCode)
	{	
	case SERVICE_CONTROL_SHUTDOWN:
	case SERVICE_CONTROL_STOP:
		nServiceCurrentStatus=SERVICE_STOP_PENDING;
		success=UpdateServiceStatus(SERVICE_STOP_PENDING,NO_ERROR,0,1,3000);
		KillService();		
		return;
	default:
		break;
	}
	UpdateServiceStatus(nServiceCurrentStatus,NO_ERROR,0,0,0);
}