c++ - 从已编译的应用程序创建 Windows 服务

Question

我想使用 Microsoft Visual Studio 2015 从我编译的 C/C++ 代码创建一个服务。我编译了我的代码并使用来自应用程序可执行文件的 sc.exe 创建了一个服务。我的代码由一个无限循环组成，它在时间间隔内将一个简单的字符串写入一个静态文件。创建服务并重启后，服务似乎自动停止了。直接运行时可执行文件工作正常。

代码如下:

#include "stdafx.h"
#include <string>
#include <cstdio>
#include <windows.h>


using namespace std;

void write_txt_file(string file_name, string input) {
    /*
    write a string to a specific txt file
    */
    FILE *f = fopen(file_name.c_str(), "a+");
    fprintf(f, "%s\n", input.c_str());
    fclose(f);
}

int main(int argc, char** argv)
{
    int i = 0;
    while (true) {
        write_txt_file("C:\\...\\Desktop\\out.txt", "Writing...#" + to_string(i));
        Sleep(5000);
        i++;
    }
}

这是我用来创建服务的命令:

sc.exe create My_service binPath= "<path to executable>" start= auto

out.txt 文件的输出是:

Writing...#0
Writing...#1
Writing...#2
Writing...#3
Writing...#4
Writing...#5
Writing...#6
Writing...#7
Writing...#8

Answer 1

在@Aconcagua 和 this reference 的帮助下我找到了一个简单的代码来使我的代码与 Windows 服务兼容。在函数 ServiceWorkerThread 中，您只需将循环放在 while block 中。可以安全地停止服务。

#include <Windows.h>
#include <tchar.h>
#include <string>
#include <cstdio>


SERVICE_STATUS        g_ServiceStatus = {0};
SERVICE_STATUS_HANDLE g_StatusHandle = NULL;
HANDLE                g_ServiceStopEvent = INVALID_HANDLE_VALUE;

VOID WINAPI ServiceMain (DWORD argc, LPTSTR *argv);
VOID WINAPI ServiceCtrlHandler (DWORD);
DWORD WINAPI ServiceWorkerThread (LPVOID lpParam);

#define SERVICE_NAME  _T("My Sample Service")


using namespace std;

void write_txt_file(string file_name, string input) {
    /*
    write a string to a specific txt file
    */
    FILE *f = fopen(file_name.c_str(), "a+");
    fprintf(f, "%s\n", input.c_str());
    fclose(f);
}


int _tmain (int argc, TCHAR *argv[])
{
    OutputDebugString(_T("My Sample Service: Main: Entry"));

    SERVICE_TABLE_ENTRY ServiceTable[] = 
    {
        {SERVICE_NAME, (LPSERVICE_MAIN_FUNCTION) ServiceMain},
        {NULL, NULL}
    };

    if (StartServiceCtrlDispatcher (ServiceTable) == FALSE)
    {
       OutputDebugString(_T("My Sample Service: Main: StartServiceCtrlDispatcher returned error"));
       return GetLastError ();
    }

    OutputDebugString(_T("My Sample Service: Main: Exit"));
    return 0;
}


VOID WINAPI ServiceMain (DWORD argc, LPTSTR *argv)
{
    DWORD Status = E_FAIL;

    OutputDebugString(_T("My Sample Service: ServiceMain: Entry"));

    g_StatusHandle = RegisterServiceCtrlHandler (SERVICE_NAME, ServiceCtrlHandler);

    if (g_StatusHandle == NULL) 
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: RegisterServiceCtrlHandler returned error"));
        goto EXIT;
    }

    // Tell the service controller we are starting
    ZeroMemory (&g_ServiceStatus, sizeof (g_ServiceStatus));
    g_ServiceStatus.dwServiceType = SERVICE_WIN32_OWN_PROCESS;
    g_ServiceStatus.dwControlsAccepted = 0;
    g_ServiceStatus.dwCurrentState = SERVICE_START_PENDING;
    g_ServiceStatus.dwWin32ExitCode = 0;
    g_ServiceStatus.dwServiceSpecificExitCode = 0;
    g_ServiceStatus.dwCheckPoint = 0;

    if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE) 
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: SetServiceStatus returned error"));
    }

    /* 
     * Perform tasks neccesary to start the service here
     */
    OutputDebugString(_T("My Sample Service: ServiceMain: Performing Service Start Operations"));

    // Create stop event to wait on later.
    g_ServiceStopEvent = CreateEvent (NULL, TRUE, FALSE, NULL);
    if (g_ServiceStopEvent == NULL) 
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: CreateEvent(g_ServiceStopEvent) returned error"));

        g_ServiceStatus.dwControlsAccepted = 0;
        g_ServiceStatus.dwCurrentState = SERVICE_STOPPED;
        g_ServiceStatus.dwWin32ExitCode = GetLastError();
        g_ServiceStatus.dwCheckPoint = 1;

        if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE)
        {
            OutputDebugString(_T("My Sample Service: ServiceMain: SetServiceStatus returned error"));
        }
        goto EXIT; 
    }    

    // Tell the service controller we are started
    g_ServiceStatus.dwControlsAccepted = SERVICE_ACCEPT_STOP;
    g_ServiceStatus.dwCurrentState = SERVICE_RUNNING;
    g_ServiceStatus.dwWin32ExitCode = 0;
    g_ServiceStatus.dwCheckPoint = 0;

    if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE)
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: SetServiceStatus returned error"));
    }

    // Start the thread that will perform the main task of the service
    HANDLE hThread = CreateThread (NULL, 0, ServiceWorkerThread, NULL, 0, NULL);

    OutputDebugString(_T("My Sample Service: ServiceMain: Waiting for Worker Thread to complete"));

    // Wait until our worker thread exits effectively signaling that the service needs to stop
    WaitForSingleObject (hThread, INFINITE);
    
    OutputDebugString(_T("My Sample Service: ServiceMain: Worker Thread Stop Event signaled"));
    
    
    /* 
     * Perform any cleanup tasks
     */
    OutputDebugString(_T("My Sample Service: ServiceMain: Performing Cleanup Operations"));

    CloseHandle (g_ServiceStopEvent);

    g_ServiceStatus.dwControlsAccepted = 0;
    g_ServiceStatus.dwCurrentState = SERVICE_STOPPED;
    g_ServiceStatus.dwWin32ExitCode = 0;
    g_ServiceStatus.dwCheckPoint = 3;

    if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE)
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: SetServiceStatus returned error"));
    }
    
    EXIT:
    OutputDebugString(_T("My Sample Service: ServiceMain: Exit"));

    return;
}


VOID WINAPI ServiceCtrlHandler (DWORD CtrlCode)
{
    OutputDebugString(_T("My Sample Service: ServiceCtrlHandler: Entry"));

    switch (CtrlCode) 
    {
     case SERVICE_CONTROL_STOP :

        OutputDebugString(_T("My Sample Service: ServiceCtrlHandler: SERVICE_CONTROL_STOP Request"));

        if (g_ServiceStatus.dwCurrentState != SERVICE_RUNNING)
           break;

        /* 
         * Perform tasks neccesary to stop the service here 
         */
        
        g_ServiceStatus.dwControlsAccepted = 0;
        g_ServiceStatus.dwCurrentState = SERVICE_STOP_PENDING;
        g_ServiceStatus.dwWin32ExitCode = 0;
        g_ServiceStatus.dwCheckPoint = 4;

        if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE)
        {
            OutputDebugString(_T("My Sample Service: ServiceCtrlHandler: SetServiceStatus returned error"));
        }

        // This will signal the worker thread to start shutting down
        SetEvent (g_ServiceStopEvent);

        break;

     default:
         break;
    }

    OutputDebugString(_T("My Sample Service: ServiceCtrlHandler: Exit"));
}


DWORD WINAPI ServiceWorkerThread (LPVOID lpParam)
{
    OutputDebugString(_T("My Sample Service: ServiceWorkerThread: Entry"));
    int i = 0;
    //  Periodically check if the service has been requested to stop
    while (WaitForSingleObject(g_ServiceStopEvent, 0) != WAIT_OBJECT_0)
    {        
        /* 
         * Perform main service function here
         */
        write_txt_file("C:\\...\\out.txt", "Writing...#" + to_string(i));
        //  Simulate some work by sleeping
        Sleep(3000);
        i++;
    }

    OutputDebugString(_T("My Sample Service: ServiceWorkerThread: Exit"));

    return ERROR_SUCCESS;
}