/usr/include/ableton/util/SafeAsyncHandler.hpp is in ableton-link-dev 1.0.0+dfsg-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 | /* Copyright 2016, Ableton AG, Berlin. All rights reserved.
*
* 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 of the License, or
* (at your option) any later version.
*
* 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/>.
*
* If you would like to incorporate Link into a proprietary software application,
* please contact <link-devs@ableton.com>.
*/
#pragma once
#include <memory>
namespace ableton
{
namespace util
{
// A utility handler for passing to async functions that may call the
// handler past the lifetime of the wrapped delegate object.
// The need for this is particularly driven by boost::asio timer
// objects, which explicitly document that they may be called without
// an error code after they have been cancelled. This has led to
// several crashes. This handler wrapper implements a useful idiom for
// avoiding this problem.
template <typename Delegate>
struct SafeAsyncHandler
{
SafeAsyncHandler(const std::shared_ptr<Delegate>& pDelegate)
: mpDelegate(pDelegate)
{
}
template <typename... T>
void operator()(T&&... t) const
{
std::shared_ptr<Delegate> pDelegate = mpDelegate.lock();
if (pDelegate)
{
(*pDelegate)(std::forward<T>(t)...);
}
}
std::weak_ptr<Delegate> mpDelegate;
};
// Factory function for easily wrapping a shared_ptr to a handler
template <typename Delegate>
SafeAsyncHandler<Delegate> makeAsyncSafe(const std::shared_ptr<Delegate>& pDelegate)
{
return {pDelegate};
}
} // namespace util
} // namespace ableton
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