Mendaftar untuk Mulai Ulang Aplikasi

Untuk mendaftarkan aplikasi Anda agar dimulai ulang, panggil fungsi RegisterApplicationRestart . Pelaporan Galat Windows (WER) akan memulai ulang aplikasi Anda jika telah berjalan setidaknya selama 60 detik sebelum menjadi tidak responsif atau mengalami pengecualian yang tidak tertangani.

Anda harus mempertimbangkan juga mendaftar untuk pemulihan, yang memungkinkan Anda menyimpan data dan informasi status yang mungkin berguna saat WER memulai ulang aplikasi Anda. WER akan memulai ulang aplikasi setelah proses pemulihan selesai, jika Anda juga mendaftar untuk pemulihan.

Setelah proses pemulihan selesai, WER mengakhiri aplikasi dan kemudian memulai ulang. Untuk aplikasi konsol, aplikasi dimulai di jendela konsol terpisah yang ditutup saat aplikasi keluar.

Catatan untuk penulis alat penginstal aplikasi: Mendaftar untuk menghidupkan ulang aplikasi juga akan menyebabkan Windows secara otomatis memulai ulang aplikasi setelah komputer dimulai ulang jika komputer dimulai ulang karena pembaruan perangkat lunak. Agar ini berfungsi, penginstal aplikasi harus memanggil fungsi ExitWindowsEx dengan set bendera EWX_RESTARTAPPS atau fungsi InitiateShutdown dengan set bendera SHUTDOWN_RESTARTAPPS.

Contoh berikut menunjukkan cara mendaftar agar WER memulai ulang aplikasi Anda. Contoh menyebabkan pelanggaran akses setelah mendaftar untuk menghidupkan ulang aplikasi. Pelanggaran akses akan diambil dengan Pelaporan Galat Windows dan akan menunjukkan pengalaman pengguna pelaporan kesalahan, termasuk mulai ulang aplikasi. Ini harus dijalankan dari jendela konsol tanpa argumen baris perintah.

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

#define RESTART_SWITCH L"/restart"

void GetRestartInfo(int argc, wchar_t* argv[], BOOL* pfIsRestart, DWORD* pdwRecordId); 
DWORD InitApplication(BOOL fIsRestart, DWORD* pdwRecordId); 
BOOL WINAPI CtrlHandler(DWORD dwControlType);
DWORD WINAPI Recover(PVOID pContext);

// A simple example to show how to use application recovery. For simplicity,
// the state information (record ID) is passed as part of the command line. 
void wmain(int argc, wchar_t* argv[])
{
    HRESULT hr = S_OK;
    DWORD dwRecordId = 0;
    BOOL fIsRestart = FALSE;

    GetRestartInfo(argc, argv, &fIsRestart, &dwRecordId);

    if (FAILED(hr = InitApplication(fIsRestart, &dwRecordId)))
    {
        wprintf(L"Failed to initialize the application.\n");
        goto cleanup;
    }

    // Do work. If you have a lot of state information, you should
    // periodically persist the state information to save time
    // in the recovery process.

    // The application must exist for at least 60 seconds for the
    // application to be restarted. Use Sleep() to mimic 60 seconds
    // worth of work.
    wprintf(L"Sleeping...\n");
    Sleep(62 * 1000);

    // Set the record ID to verify restart value.
    dwRecordId = 10;

    // Generate an access violation to force a restart. If we've already
    // restarted just exit because the example already demonstrated
    // the restart feature.
    if (FALSE == fIsRestart)
    {
        wprintf(L"Causing access violation...\n");
        int* p = NULL;
        *p = 5;
    }

cleanup:

    wprintf(L"Exiting...\n");
}


// Get the restart info from the command line. The command line is 
// of the form, /restart -r <RecordId>. The application 
// is being restarted if the first argument is /restart.
void GetRestartInfo(int argc, wchar_t* argv[], BOOL* pfIsRestart, DWORD* pdwRecordId) 
{
    if (argc > 1)
    {
        if (!wcsncmp(RESTART_SWITCH, argv[1], sizeof(RESTART_SWITCH)))
        {
            *pfIsRestart = TRUE;
            *pdwRecordId = _wtoi(argv[3]);
        }
    }

}

// Initialize the application. If this is a restart, use the state 
// information to reset the state of the application. This example 
// does not fail the initialization process if the process of 
// registering for application recovery and restart failed.
DWORD InitApplication(BOOL fIsRestart, DWORD* pdwRecordId)
{
    DWORD status = ERROR_SUCCESS;  // Set only if the initializing the application fails,
    HRESULT hr = S_OK;             // not if registering for recovery and restart fails.
    WCHAR wsCommandLine[RESTART_MAX_CMD_LINE];

    wprintf(L"Entering InitApplication...\n");

    if (fIsRestart)
    {
        // TODO: Use the record ID to initialize the application.
        wprintf(L"Restart record ID is %lu\n", *pdwRecordId);
    }
    else
    {
        // This is not a restart, so initialize the application accordingly.
    }

    // Register for restart. The command line is updated in the recovery callback.
    RtlZeroMemory(wsCommandLine, sizeof(wsCommandLine));
    StringCchPrintf(wsCommandLine, sizeof(wsCommandLine), L"/restart -r %lu", *pdwRecordId);

    hr = RegisterApplicationRestart(wsCommandLine, RESTART_NO_PATCH | RESTART_NO_REBOOT);
    if (FAILED(hr))
    {
        // Not failing because the registration failed.
        wprintf(L"RegisterApplicationRestart failed with ox%x.\n", hr);
        goto cleanup;
    }

    // Register the callback that handles the control event notifications.
    // Used for recovery when an installer is updating a component of the
    // application.
    if (!SetConsoleCtrlHandler(CtrlHandler, TRUE))
    {
        // Not failing initialization because the registration failed.
        // Consider calling UnregisterApplicationRestart if you must
        // have the latest state information.
        wprintf(L"SetConsoleCtrlHandler failed.\n");
        goto cleanup;
    }

    // Register the callback that handles recovery when the application
    // encounters an unhandled exception or becomes unresponsive.
    hr = RegisterApplicationRecoveryCallback(Recover, pdwRecordId, RECOVERY_DEFAULT_PING_INTERVAL, 0);
    if (FAILED(hr))
    {
        // Not failing initialization because the registration failed.
        // Consider calling UnregisterApplicationRestart if you must
        // have the latest state information.
        wprintf(L"RegisterApplicationRecoveryCallback failed with ox%x.\n", hr);
        goto cleanup;
    }

cleanup:

    return hr;
}


// Implement the callback for handling control character events.
// You'd implement this callback if an installer could update a
// component of your application. The system sends a CTRL_C_EVENT
// notification when an installer needs to shutdown your application
// or restart the computer in order to complete the installation.
// You can use the CTRL_C_EVENT to save final state information or
// data before exiting.
BOOL WINAPI CtrlHandler(DWORD dwControlType)
{
    wprintf(L"Entering CtrlHandler...\n");

    switch (dwControlType)
    {
        case CTRL_C_EVENT:
            wprintf(L"Handling CTRL_C_EVENT\n");
            return FALSE;

        // Other cases go here.

        default: 
            wprintf(L"Other, %ul\n", dwControlType);
            return FALSE;
    }
}


// Implement the recovery callback. This callback lets the application
// save state information or data in the event that the application
// encounters an unhandled exception or becomes unresponsive.
DWORD WINAPI Recover(PVOID pContext)
{
    HRESULT hr = S_OK;
    BOOL bCanceled = FALSE;
    DWORD dwRecordId = *(DWORD*)pContext;
    WCHAR wsCommandLine[RESTART_MAX_CMD_LINE];

    wprintf(L"Entering Recover callback...\n");

    // Do recovery work. 

    // Update the restart command line.
    RtlZeroMemory(wsCommandLine, sizeof(wsCommandLine));
    StringCchPrintf(wsCommandLine, sizeof(wsCommandLine), L"/restart -r %lu", dwRecordId);

    hr = RegisterApplicationRestart(wsCommandLine, RESTART_NO_PATCH | RESTART_NO_REBOOT);
    if (FAILED(hr))
    {
        // Not failing because the registration failed.
        wprintf(L"RegisterApplicationRestart failed with ox%x.\n", hr);
    }

    // You must call the ApplicationRecoveryInProgress function within
    // the specified ping interval or the recovery callback exits.
    // Typically, you would do a block of work, call the function, and repeat.
    hr = ApplicationRecoveryInProgress(&bCanceled);
    if (bCanceled)  
    {
        wprintf(L"Recovery was canceled by the user.\n");
        goto cleanup;
    }

    // Do more recovery work. 
    
    // You could also call the RegisterApplicationRestart function to
    // update the command line used for the restart.

cleanup:

    // Save the state file.

    wprintf(L"Leaving Recover callback...\n");
    ApplicationRecoveryFinished((bCanceled) ? FALSE: TRUE);

    return 0;
}