163 lines
4.2 KiB
C
163 lines
4.2 KiB
C
|
/*
|
||
|
|
This file is part of Telegram Desktop,
|
||
|
|
the official desktop version of Telegram messaging app, see https://telegram.org
|
||
|
|
|
||
|
|
Telegram Desktop 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 3 of the License, or
|
||
|
|
(at your option) any later version.
|
||
|
|
|
||
|
|
It 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.
|
||
|
|
|
||
|
|
In addition, as a special exception, the copyright holders give permission
|
||
|
|
to link the code of portions of this program with the OpenSSL library.
|
||
|
|
|
||
|
|
Full license: https://github.com/telegramdesktop/tdesktop/blob/master/LICENSE
|
||
|
|
Copyright (c) 2014-2017 John Preston, https://desktop.telegram.org
|
||
|
|
*/
|
||
|
|
#pragma once
|
||
|
|
|
||
|
|
#include <rpl/producer.h>
|
||
|
|
|
||
|
|
namespace rpl {
|
||
|
|
namespace details {
|
||
|
|
|
||
|
|
struct merge_state {
|
||
|
|
merge_state(int working) : working(working) {
|
||
|
|
}
|
||
|
|
int working = 0;
|
||
|
|
};
|
||
|
|
|
||
|
|
template <size_t Index, typename consumer_type>
|
||
|
|
class merge_subscribe_one {
|
||
|
|
public:
|
||
|
|
merge_subscribe_one(
|
||
|
|
const consumer_type &consumer,
|
||
|
|
merge_state *state)
|
||
|
|
: _consumer(consumer)
|
||
|
|
, _state(state) {
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename Value, typename Error, typename Generator>
|
||
|
|
void subscribe(producer<Value, Error, Generator> &&producer) {
|
||
|
|
_consumer.add_lifetime(std::move(producer).start(
|
||
|
|
[consumer = _consumer](auto &&value) {
|
||
|
|
consumer.put_next_forward(
|
||
|
|
std::forward<decltype(value)>(value));
|
||
|
|
}, [consumer = _consumer](auto &&error) {
|
||
|
|
consumer.put_error_forward(
|
||
|
|
std::forward<decltype(error)>(error));
|
||
|
|
}, [consumer = _consumer, state = _state] {
|
||
|
|
if (!--state->working) {
|
||
|
|
consumer.put_done();
|
||
|
|
}
|
||
|
|
}));
|
||
|
|
}
|
||
|
|
|
||
|
|
private:
|
||
|
|
const consumer_type &_consumer;
|
||
|
|
merge_state *_state = nullptr;
|
||
|
|
|
||
|
|
};
|
||
|
|
|
||
|
|
template <
|
||
|
|
typename consumer_type,
|
||
|
|
typename Value,
|
||
|
|
typename Error,
|
||
|
|
typename ...Generators,
|
||
|
|
std::size_t ...I>
|
||
|
|
inline void merge_subscribe(
|
||
|
|
const consumer_type &consumer,
|
||
|
|
merge_state *state,
|
||
|
|
std::index_sequence<I...>,
|
||
|
|
std::tuple<producer<Value, Error, Generators>...> &&saved) {
|
||
|
|
auto consume = { (
|
||
|
|
details::merge_subscribe_one<I, consumer_type>(
|
||
|
|
consumer,
|
||
|
|
state
|
||
|
|
).subscribe(std::get<I>(std::move(saved))), 0)... };
|
||
|
|
(void)consume;
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename ...Producers>
|
||
|
|
class merge_implementation_helper;
|
||
|
|
|
||
|
|
template <typename ...Producers>
|
||
|
|
merge_implementation_helper<std::decay_t<Producers>...>
|
||
|
|
make_merge_implementation_helper(Producers &&...producers) {
|
||
|
|
return merge_implementation_helper<std::decay_t<Producers>...>(
|
||
|
|
std::forward<Producers>(producers)...);
|
||
|
|
}
|
||
|
|
|
||
|
|
template <
|
||
|
|
typename Value,
|
||
|
|
typename Error,
|
||
|
|
typename ...Generators>
|
||
|
|
class merge_implementation_helper<producer<Value, Error, Generators>...> {
|
||
|
|
public:
|
||
|
|
merge_implementation_helper(
|
||
|
|
producer<Value, Error, Generators> &&...producers)
|
||
|
|
: _saved(std::make_tuple(std::move(producers)...)) {
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename Handlers>
|
||
|
|
lifetime operator()(const consumer<Value, Error, Handlers> &consumer) {
|
||
|
|
auto state = consumer.template make_state<
|
||
|
|
details::merge_state>(sizeof...(Generators));
|
||
|
|
constexpr auto kArity = sizeof...(Generators);
|
||
|
|
details::merge_subscribe(
|
||
|
|
consumer,
|
||
|
|
state,
|
||
|
|
std::make_index_sequence<kArity>(),
|
||
|
|
std::move(_saved));
|
||
|
|
|
||
|
|
return lifetime();
|
||
|
|
}
|
||
|
|
|
||
|
|
private:
|
||
|
|
std::tuple<producer<Value, Error, Generators>...> _saved;
|
||
|
|
|
||
|
|
};
|
||
|
|
|
||
|
|
template <
|
||
|
|
typename Value,
|
||
|
|
typename Error,
|
||
|
|
typename ...Generators>
|
||
|
|
inline auto merge_implementation(
|
||
|
|
producer<Value, Error, Generators> &&...producers) {
|
||
|
|
return make_producer<Value, Error>(
|
||
|
|
make_merge_implementation_helper(std::move(producers)...));
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename ...Args>
|
||
|
|
struct merge_producers : std::false_type {
|
||
|
|
};
|
||
|
|
|
||
|
|
template <typename ...Args>
|
||
|
|
constexpr bool merge_producers_v
|
||
|
|
= merge_producers<Args...>::value;
|
||
|
|
|
||
|
|
template <
|
||
|
|
typename Value,
|
||
|
|
typename Error,
|
||
|
|
typename ...Generators>
|
||
|
|
struct merge_producers<
|
||
|
|
producer<Value, Error, Generators>...>
|
||
|
|
: std::true_type {
|
||
|
|
};
|
||
|
|
|
||
|
|
} // namespace details
|
||
|
|
|
||
|
|
template <
|
||
|
|
typename ...Args,
|
||
|
|
typename = std::enable_if_t<
|
||
|
|
details::merge_producers_v<Args...>>>
|
||
|
|
inline decltype(auto) merge(Args &&...args) {
|
||
|
|
return details::merge_implementation(std::move(args)...);
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace rpl
|