mirror of
https://github.com/matrix-construct/construct
synced 2024-11-03 12:28:52 +01:00
65 lines
2.6 KiB
C++
65 lines
2.6 KiB
C++
/*
|
|
* Copyright (C) 2016 Charybdis Development Team
|
|
* Copyright (C) 2016 Jason Volk <jason@zemos.net>
|
|
*
|
|
* Permission to use, copy, modify, and/or distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice is present in all copies.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
|
|
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
|
|
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#pragma once
|
|
#define HAVE_IRCD_JS_CONTRACT_H
|
|
|
|
namespace ircd {
|
|
namespace js {
|
|
|
|
// contract is a promise from C to a future in JS. When a task has no more pending contracts,
|
|
// it ceases to exist.
|
|
//
|
|
// * The promise is the `struct contract` instantiated in C.
|
|
// * The future is returned into JS as an object trapped by "future" (future.so)
|
|
// * C unconditionally enters the closure to report result.
|
|
// * * if the C closure returns a `value` the "value" field is set in JS
|
|
// * * if the C closure throws an exception the "error" field conveys the exception in JS
|
|
// *
|
|
// * "id": uint
|
|
// * "value": object [optional]
|
|
// * "error": exception object [optional]
|
|
//
|
|
struct contract
|
|
:std::weak_ptr<struct task>
|
|
{
|
|
using closure = std::function<value ()>;
|
|
|
|
object future;
|
|
|
|
operator const object &() const { return future; }
|
|
operator object &() { return future; }
|
|
operator value() const { return future; }
|
|
|
|
// Enter this closure and return or throw to complete the result contract.
|
|
void operator()(const closure &) noexcept;
|
|
|
|
// The future object is constructed using the "future" trap.
|
|
// The task is automatically found with task::get() in the overload without a task argument.
|
|
contract(struct task &, object::handle future);
|
|
contract(object::handle future);
|
|
contract(contract &&) = default;
|
|
contract(const contract &) = default;
|
|
~contract() noexcept;
|
|
};
|
|
|
|
} // namespace js
|
|
} // namespace ircd
|