winshutdownmonitor.cpp

Go to the documentation of this file.

// Copyright (c) 2014 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
#include "winshutdownmonitor.h"
 
#if defined(Q_OS_WIN)
#include "init.h"
#include "util.h"
 
#include <windows.h>
 
#include <QDebug>
 
#include <openssl/rand.h>
 
// If we don't want a message to be processed by Qt, return true and set result to
// the value that the window procedure should return. Otherwise return false.
bool WinShutdownMonitor::nativeEventFilter(const QByteArray& eventType, void* pMessage, long* pnResult)
{
    Q_UNUSED(eventType);
 
    MSG* pMsg = static_cast<MSG*>(pMessage);
 
    // Seed OpenSSL PRNG with Windows event data (e.g.  mouse movements and other user interactions)
    if (RAND_event(pMsg->message, pMsg->wParam, pMsg->lParam) == 0) {
        // Warn only once as this is performance-critical
        static bool warned = false;
        if (!warned) {
            LogPrintf("%s: OpenSSL RAND_event() failed to seed OpenSSL PRNG with enough data.\n", __func__);
            warned = true;
        }
    }
 
    switch (pMsg->message) {
    case WM_QUERYENDSESSION: {
        // Initiate a client shutdown after receiving a WM_QUERYENDSESSION and block
        // Windows session end until we have finished client shutdown.
        StartShutdown();
        *pnResult = FALSE;
        return true;
    }
 
    case WM_ENDSESSION: {
        *pnResult = FALSE;
        return true;
    }
    }
 
    return false;
}
 
void WinShutdownMonitor::registerShutdownBlockReason(const QString& strReason, const HWND& mainWinId)
{
    typedef BOOL(WINAPI * PSHUTDOWNBRCREATE)(HWND, LPCWSTR);
    PSHUTDOWNBRCREATE shutdownBRCreate = (PSHUTDOWNBRCREATE)GetProcAddress(GetModuleHandleA("User32.dll"), "ShutdownBlockReasonCreate");
    if (shutdownBRCreate == NULL) {
        qDebug() << "registerShutdownBlockReason: GetProcAddress for ShutdownBlockReasonCreate failed";
        return;
    }
 
    if (shutdownBRCreate(mainWinId, strReason.toStdWString().c_str()))
        qDebug() << "registerShutdownBlockReason: Successfully registered: " + strReason;
    else
        qDebug() << "registerShutdownBlockReason: Failed to register: " + strReason;
}
#endif