// Copyright (c) 2023 Huawei Device Co., Ltd.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use libc::{c_int, c_uchar, c_uint, c_ulonglong, c_void};

// Unstable interface, rust encapsulation temporarily not provided

type FfrtSysEventHandleT = *mut c_void;
type DestroyFunc = extern "C" fn(*mut c_void);
type FfrtFdCallBack = extern "C" fn(*const c_void, c_uint, c_uchar);
type FfrtExecHook = extern "C" fn(*mut c_void);
type FfrtTimerHandle = *mut c_void;

#[link(name = "ffrt")]
// sys_event.h
extern "C" {
    #![allow(unused)]
    fn ffrt_sys_event_create(ty: c_int, fd: usize, filter: usize) -> FfrtSysEventHandleT;
    fn ffrt_sys_event_wait(event: FfrtSysEventHandleT, sec: i64) -> c_int;
    fn ffrt_sys_event_destroy(event: FfrtSysEventHandleT, func: DestroyFunc, arg: *mut c_void);

    /// Registers the fd to ffrt's epoll. Callback will be called when io events
    /// arrived.
    pub fn ffrt_poller_register(
        fd: c_int,
        events: c_uint,
        data: *const c_void,
        callback: FfrtFdCallBack,
    ) -> c_int;

    /// Deregisters the fd from ffrt's epoll.
    pub fn ffrt_poller_deregister(fd: c_int) -> c_int;

    /// Registers a timer to ffrt's timer poller. Callback will be called when
    /// timer events arrived.
    pub fn ffrt_timer_start(
        duration: c_ulonglong,
        waker: *mut c_void,
        callback: FfrtExecHook,
    ) -> FfrtTimerHandle;

    /// Deregisters the timer from ffrt's timer poller
    pub fn ffrt_timer_stop(handle: FfrtTimerHandle);

    /// Checks whether the timer has expired. A returned value of 1 indicates
    /// the timer has reached its deadline, otherwise, the timer has not expired
    /// yet.
    pub fn ffrt_timer_query(handle: FfrtTimerHandle) -> c_int;

    /// Wakes up the poller to poll timer/io events.
    pub fn ffrt_poller_wakeup();
}