用 C 语言编写 Windows 服务程序

// NTService.cpp : Defines the entry point for the console application.
//

#include <windows.h>
#include <stdio.h>

#define SLEEP_TIME 5000
#define LOGFILE "C:/MyServices/memstatus.txt"

SERVICE_STATUS ServiceStatus;
SERVICE_STATUS_HANDLE hStatus;

void ServiceMain(int argc, char** argv);
void ControlHandler(DWORD request);
int InitService();
int WriteToLog(char* str);

int main(int argc, char* argv[])
{
SERVICE_TABLE_ENTRY ServiceTable[2];
ServiceTable[0].lpServiceName = "MemoryStatus";
ServiceTable[0].lpServiceProc = (LPSERVICE_MAIN_FUNCTION)ServiceMain;

ServiceTable[1].lpServiceName = NULL;
ServiceTable[1].lpServiceProc = NULL;

// 启动服务的控制分派机线程
StartServiceCtrlDispatcher(ServiceTable);
}

void ServiceMain(int argc, char** argv)
{
int error;

ServiceStatus.dwServiceType =
SERVICE_WIN32;
ServiceStatus.dwCurrentState =
SERVICE_START_PENDING;
ServiceStatus.dwControlsAccepted =
SERVICE_ACCEPT_STOP |
SERVICE_ACCEPT_SHUTDOWN;
ServiceStatus.dwWin32ExitCode = 0;
ServiceStatus.dwServiceSpecificExitCode = 0;
ServiceStatus.dwCheckPoint = 0;
ServiceStatus.dwWaitHint = 0;

hStatus = RegisterServiceCtrlHandler(
"MemoryStatus",
(LPHANDLER_FUNCTION)ControlHandler);
if (hStatus == (SERVICE_STATUS_HANDLE)0)
{
// Registering Control Handler failed
return;
}
// Initialize Service
error = InitService();
if (!error)
{
// Initialization failed
ServiceStatus.dwCurrentState =
SERVICE_STOPPED;
ServiceStatus.dwWin32ExitCode = -1;
SetServiceStatus(hStatus, &ServiceStatus);
return;
}
// We report the running status to SCM.
ServiceStatus.dwCurrentState =
SERVICE_RUNNING;
SetServiceStatus (hStatus, &ServiceStatus);

MEMORYSTATUS memory;
// The worker loop of a service
while (ServiceStatus.dwCurrentState ==
SERVICE_RUNNING)
{
char buffer[16];
GlobalMemoryStatus(&memory);
sprintf(buffer, "%d", memory.dwAvailPhys);
int result = WriteToLog(buffer);
if (result)
{
ServiceStatus.dwCurrentState =
SERVICE_STOPPED;
ServiceStatus.dwWin32ExitCode = -1;
SetServiceStatus(hStatus,
&ServiceStatus);
return;
}
Sleep(SLEEP_TIME);
}
return;
}

void ControlHandler(DWORD request)
{
switch(request)
{
case SERVICE_CONTROL_STOP:
WriteToLog("Monitoring stopped.");

ServiceStatus.dwWin32ExitCode = 0;
ServiceStatus.dwCurrentState = SERVICE_STOPPED;
SetServiceStatus (hStatus, &ServiceStatus);
return;

case SERVICE_CONTROL_SHUTDOWN:
WriteToLog("Monitoring stopped.");

ServiceStatus.dwWin32ExitCode = 0;
ServiceStatus.dwCurrentState = SERVICE_STOPPED;
SetServiceStatus (hStatus, &ServiceStatus);
return;

default:
break;
}

// Report current status
SetServiceStatus (hStatus, &ServiceStatus);

return;
}

int WriteToLog(char* str)
{
FILE* log;
log = fopen(LOGFILE, "a+");
if (log == NULL)
return -1;
fprintf(log, "%s ", str);
fclose(log);
return 0;
}

int InitService(){
WriteToLog("Monitoring started.");
return true;
}