停止服务
服务控制程序可以通过使用 ControlService 函数发送SERVICE_CONTROL_STOP请求来停止服务。 如果 服务控制管理器 (SCM) 收到服务SERVICE_CONTROL_STOP请求，它会通过将请求转发到服务的 ServiceMain 函数来指示服务停止。 但是，如果 SCM 确定其他正在运行的服务依赖于指定的服务，则不会转发停止请求。 而是返回ERROR_DEPENDENT_SERVICES_RUNNING。 因此，若要以编程方式停止此类服务，必须先枚举并停止其依赖服务。
以下示例中的 DoStopSvc 函数演示如何停止服务和任何依赖服务。 szSvcName 变量是一个全局变量，其中包含要停止的服务的名称。 有关设置此变量的完整示例，请参阅 SvcControl.cpp。
//
// Purpose:
// Stops the service.
//
// Parameters:
// None
//
// Return value:
// None
//
VOID __stdcall DoStopSvc()
{
SERVICE_STATUS_PROCESS ssp;
DWORD dwStartTime = GetTickCount();
DWORD dwBytesNeeded;
DWORD dwTimeout = 30000; // 30-second time-out
DWORD dwWaitTime;
// Get a handle to the SCM database.
schSCManager = OpenSCManager(
NULL, // local computer
NULL, // ServicesActive database
SC_MANAGER_ALL_ACCESS); // full access rights
if (NULL == schSCManager)
{
printf("OpenSCManager failed (%d)\n", GetLastError());
return;
}
// Get a handle to the service.
schService = OpenService(
schSCManager, // SCM database
szSvcName, // name of service
SERVICE_STOP |
SERVICE_QUERY_STATUS |
SERVICE_ENUMERATE_DEPENDENTS);
if (schService == NULL)
{
printf("OpenService failed (%d)\n", GetLastError());
CloseServiceHandle(schSCManager);
return;
}
// Make sure the service is not already stopped.
if ( !QueryServiceStatusEx(
schService,
SC_STATUS_PROCESS_INFO,
(LPBYTE)&ssp,
sizeof(SERVICE_STATUS_PROCESS),
&dwBytesNeeded ) )
{
printf("QueryServiceStatusEx failed (%d)\n", GetLastError());
goto stop_cleanup;
}
if ( ssp.dwCurrentState == SERVICE_STOPPED )
{
printf("Service is already stopped.\n");
goto stop_cleanup;
}
// If a stop is pending, wait for it.
while ( ssp.dwCurrentState == SERVICE_STOP_PENDING )
{
printf("Service stop pending...\n");
// Do not wait longer than the wait hint. A good interval is
// one-tenth of the wait hint but not less than 1 second
// and not more than 10 seconds.
dwWaitTime = ssp.dwWaitHint / 10;
if( dwWaitTime < 1000 )
dwWaitTime = 1000;
else if ( dwWaitTime > 10000 )
dwWaitTime = 10000;
Sleep( dwWaitTime );
if ( !QueryServiceStatusEx(
schService,
SC_STATUS_PROCESS_INFO,
(LPBYTE)&ssp,
sizeof(SERVICE_STATUS_PROCESS),
&dwBytesNeeded ) )
{
printf("QueryServiceStatusEx failed (%d)\n", GetLastError());
goto stop_cleanup;
}
if ( ssp.dwCurrentState == SERVICE_STOPPED )
{
printf("Service stopped successfully.\n");
goto stop_cleanup;
}
if ( GetTickCount() - dwStartTime > dwTimeout )
{
printf("Service stop timed out.\n");
goto stop_cleanup;
}
}
// If the service is running, dependencies must be stopped first.
StopDependentServices();
// Send a stop code to the service.
if ( !ControlService(
schService,
SERVICE_CONTROL_STOP,
(LPSERVICE_STATUS) &ssp ) )
{
printf( "ControlService failed (%d)\n", GetLastError() );
goto stop_cleanup;
}
// Wait for the service to stop.
while ( ssp.dwCurrentState != SERVICE_STOPPED )
{
Sleep( ssp.dwWaitHint );
if ( !QueryServiceStatusEx(
schService,
SC_STATUS_PROCESS_INFO,
(LPBYTE)&ssp,
sizeof(SERVICE_STATUS_PROCESS),
&dwBytesNeeded ) )
{
printf( "QueryServiceStatusEx failed (%d)\n", GetLastError() );
goto stop_cleanup;
}
if ( ssp.dwCurrentState == SERVICE_STOPPED )
break;
if ( GetTickCount() - dwStartTime > dwTimeout )
{
printf( "Wait timed out\n" );
goto stop_cleanup;
}
}
printf("Service stopped successfully\n");
stop_cleanup:
CloseServiceHandle(schService);
CloseServiceHandle(schSCManager);
}
BOOL __stdcall StopDependentServices()
{
DWORD i;
DWORD dwBytesNeeded;
DWORD dwCount;
LPENUM_SERVICE_STATUS lpDependencies = NULL;
ENUM_SERVICE_STATUS ess;
SC_HANDLE hDepService;
SERVICE_STATUS_PROCESS ssp;
DWORD dwStartTime = GetTickCount();
DWORD dwTimeout = 30000; // 30-second time-out
// Pass a zero-length buffer to get the required buffer size.
if ( EnumDependentServices( schService, SERVICE_ACTIVE,
lpDependencies, 0, &dwBytesNeeded, &dwCount ) )
{
// If the Enum call succeeds, then there are no dependent
// services, so do nothing.
return TRUE;
}
else
{
if ( GetLastError() != ERROR_MORE_DATA )
return FALSE; // Unexpected error
// Allocate a buffer for the dependencies.
lpDependencies = (LPENUM_SERVICE_STATUS) HeapAlloc(
GetProcessHeap(), HEAP_ZERO_MEMORY, dwBytesNeeded );
if ( !lpDependencies )
return FALSE;
__try {
// Enumerate the dependencies.
if ( !EnumDependentServices( schService, SERVICE_ACTIVE,
lpDependencies, dwBytesNeeded, &dwBytesNeeded,
&dwCount ) )
return FALSE;
for ( i = 0; i < dwCount; i++ )
{
ess = *(lpDependencies + i);
// Open the service.
hDepService = OpenService( schSCManager,
ess.lpServiceName,
SERVICE_STOP | SERVICE_QUERY_STATUS );
if ( !hDepService )
return FALSE;
__try {
// Send a stop code.
if ( !ControlService( hDepService,
SERVICE_CONTROL_STOP,
(LPSERVICE_STATUS) &ssp ) )
return FALSE;
// Wait for the service to stop.
while ( ssp.dwCurrentState != SERVICE_STOPPED )
{
Sleep( ssp.dwWaitHint );
if ( !QueryServiceStatusEx(
hDepService,
SC_STATUS_PROCESS_INFO,
(LPBYTE)&ssp,
sizeof(SERVICE_STATUS_PROCESS),
&dwBytesNeeded ) )
return FALSE;
if ( ssp.dwCurrentState == SERVICE_STOPPED )
break;
if ( GetTickCount() - dwStartTime > dwTimeout )
return FALSE;
}
}
__finally
{
// Always release the service handle.
CloseServiceHandle( hDepService );
}
}
}
__finally
{
// Always free the enumeration buffer.
HeapFree( GetProcessHeap(), 0, lpDependencies );
}
}
return TRUE;
}
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