deluge/include/libtorrent/asio/detail/call_stack.hpp

91 lines
1.9 KiB
C++

//
// call_stack.hpp
// ~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2006 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// 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)
//
#ifndef ASIO_DETAIL_CALL_STACK_HPP
#define ASIO_DETAIL_CALL_STACK_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include "asio/detail/push_options.hpp"
#include "asio/detail/noncopyable.hpp"
#include "asio/detail/tss_ptr.hpp"
namespace asio {
namespace detail {
// Helper class to determine whether or not the current thread is inside an
// invocation of io_service::run() for a specified io_service object.
template <typename Owner>
class call_stack
{
public:
// Context class automatically pushes an owner on to the stack.
class context
: private noncopyable
{
public:
// Push the owner on to the stack.
explicit context(Owner* d)
: owner_(d),
next_(call_stack<Owner>::top_)
{
call_stack<Owner>::top_ = this;
}
// Pop the owner from the stack.
~context()
{
call_stack<Owner>::top_ = next_;
}
private:
friend class call_stack<Owner>;
// The owner associated with the context.
Owner* owner_;
// The next element in the stack.
context* next_;
};
friend class context;
// Determine whether the specified owner is on the stack.
static bool contains(Owner* d)
{
context* elem = top_;
while (elem)
{
if (elem->owner_ == d)
return true;
elem = elem->next_;
}
return false;
}
private:
// The top of the stack of calls for the current thread.
static tss_ptr<context> top_;
};
template <typename Owner>
tss_ptr<typename call_stack<Owner>::context>
call_stack<Owner>::top_;
} // namespace detail
} // namespace asio
#include "asio/detail/pop_options.hpp"
#endif // ASIO_DETAIL_CALL_STACK_HPP