tdlight/tdutils/td/utils/Context.h
2021-01-01 15:57:46 +03:00

45 lines
950 B
C++

//
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2021
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#pragma once
#include "td/utils/port/thread_local.h"
namespace td {
template <class Impl>
class Context {
public:
static Impl *get() {
return context_;
}
class Guard {
public:
explicit Guard(Impl *new_context) {
old_context_ = context_;
context_ = new_context;
}
~Guard() {
context_ = old_context_;
}
Guard(const Guard &) = delete;
Guard &operator=(const Guard &) = delete;
Guard(Guard &&) = delete;
Guard &operator=(Guard &&) = delete;
private:
Impl *old_context_;
};
private:
static TD_THREAD_LOCAL Impl *context_;
};
template <class Impl>
TD_THREAD_LOCAL Impl *Context<Impl>::context_;
} // namespace td