helpers.hpp

Go to the documentation of this file.

 
#pragma once
 
#include "condy/concepts.hpp"
#include "condy/condy_uring.hpp"
#include "condy/context.hpp"
#include <type_traits>
 
#if !IO_URING_CHECK_VERSION(2, 4) // >= 2.4
#define CONDY_FILE_INDEX_ALLOC IORING_FILE_INDEX_ALLOC
#else
#define CONDY_FILE_INDEX_ALLOC (IORING_FILE_INDEX_ALLOC - 1)
#endif
 
namespace condy {
 
namespace detail {
 
template <typename CoroFunc> struct SpawnHelper {
    void operator()(auto &&res) noexcept {
        // This helper will only be called inside the coroutine context, so it's
        // safe to assume that the runtime is available.
        assert(detail::Context::current().runtime() != nullptr);
        co_spawn(func(std::forward<decltype(res)>(res))).detach();
    }
    CoroFunc func;
};
 
template <typename Channel> struct PushHelper {
    void operator()(auto &&res) noexcept {
        channel.force_push(std::forward<decltype(res)>(res));
    }
    Channel &channel;
};
 
} // namespace detail

template <typename CoroFunc> auto will_spawn(CoroFunc &&coro) {
    return detail::SpawnHelper<std::decay_t<CoroFunc>>{
        std::forward<CoroFunc>(coro)};
}

template <typename Channel> auto will_push(Channel &channel) {
    return detail::PushHelper<Channel>{channel};
}
 
namespace detail {
 
struct FixedFd {
    int value;
    operator int() const { return value; }
};
 
template <typename T> struct FixedBuffer {
    T value;
    int buf_index;
};
 
} // namespace detail

inline auto fixed(int fd) { return detail::FixedFd{fd}; }

template <BufferLike Buffer> auto fixed(int buf_index, Buffer &&buf) {
    return detail::FixedBuffer<Buffer>{std::forward<Buffer>(buf), buf_index};
}

inline auto fixed(int buf_index, const struct iovec *iov) {
    return detail::FixedBuffer<const iovec *>{iov, buf_index};
}

inline auto fixed(int buf_index, const struct msghdr *msg) {
    return detail::FixedBuffer<const msghdr *>{msg, buf_index};
}
 
} // namespace condy