keepassxc/src/core/AsyncTask.h
Barnabás Pőcze 16b3d32ca5
Fix Botan 3 build (#9388)
* SymmetricCipher: Fix Botan 3 build

Botan commit 819cf8fe6278a19b8266f449228f02fc28a4f784 changed
Botan::Cipher_Dir to be a scoped enumeration, so the users
must be adapted.

This change causes no issues with Botan 2 because normal
enumeration values can also be referred to the same way
scoped enumeration values are accessed.

* Auto detect Botan3

* AsyncTask: Do not use `std::result_of`

`std::result_of` was deprecated in C++17 and then it was
subsequently removed in C++20. One could use `std::invoke_result_t`,
but let Qt figure out the return type instead.

* Collapse Botan2 and Botan3 find package into one

* Update COPYING

---------

Co-authored-by: Jonathan White <support@dmapps.us>
2023-05-07 08:48:58 -04:00

81 lines
2.7 KiB
C++

/*
* Copyright (C) 2017 KeePassXC Team <team@keepassxc.org>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 or (at your option)
* version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef KEEPASSXC_ASYNCTASK_HPP
#define KEEPASSXC_ASYNCTASK_HPP
#include <QFutureWatcher>
#include <QtConcurrent>
/**
* Asynchronously run computations outside the GUI thread.
*/
namespace AsyncTask
{
/**
* Wait for the given future without blocking the event loop.
*
* @param future future to wait for
* @return async task result
*/
template <typename T> T waitForFuture(QFuture<T> future)
{
QEventLoop loop;
QFutureWatcher<T> watcher;
QObject::connect(&watcher, SIGNAL(finished()), &loop, SLOT(quit()));
watcher.setFuture(future);
loop.exec();
return future.result();
}
/**
* Run a given task and wait for it to finish without blocking the event loop.
*
* @param task std::function object to run
* @return async task result
*/
template <typename FunctionObject> decltype(auto) runAndWaitForFuture(FunctionObject task)
{
return waitForFuture(QtConcurrent::run(task));
}
/**
* Run a given task then call the defined callback. Prevents event loop blocking and
* ensures the validity of the follow-on task through the context. If the context is
* deleted, the callback will not be processed preventing use after free errors.
*
* @param task std::function object to run
* @param context QObject responsible for calling this function
* @param callback std::function object to run after the task completes
*/
template <typename FunctionObject, typename FunctionObject2>
void runThenCallback(FunctionObject task, QObject* context, FunctionObject2 callback)
{
auto future = QtConcurrent::run(task);
auto watcher = new QFutureWatcher<decltype(future.result())>(context);
QObject::connect(watcher, &QFutureWatcherBase::finished, context, [=]() {
watcher->deleteLater();
callback(future.result());
});
watcher->setFuture(future);
}
}; // namespace AsyncTask
#endif // KEEPASSXC_ASYNCTASK_HPP