AuroraRuntime/Include/Aurora/Threading/WaitFor.hpp

/***
    Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: WaitFor.hpp
    Date: 2021-6-10
    Author: Reece
***/
#pragma once

namespace Aurora::Threading
{
    using PollCallback_cb = AuFunction<bool()>;
    
    AUKN_SYM bool YieldPollNs(bool bPermitMultipleContextSwitches, AuUInt64 qwAbsTimeoutNs, PollCallback_cb cb);

    AUKN_SYM bool WaitForAbsNS(IWaitable *pWaitable, AuUInt64 qwAbsTimeout = 0);
    AUKN_SYM bool TryWait(IWaitable *pWaitable);

    static const auto kWaitForFlagTimeoutIsNanoseconds = 1ul;
    static const auto kWaitForFlagTimeoutIsAbsolute    = 1ul << 1;
    static const auto kWaitForFlagTimeoutIsOr          = 1ul << 2;

    /**
     *  Waits for a list of IWaitable objects to complete.
     *  See: Mutex, CriticalSection, Semaphore, Event, Thread, Async, and others
     *  On timeout, returns false
     *  On error, waitables are restored to their state at the point of WaitFors
     */
    AUKN_SYM bool WaitFor(const AuList<IWaitable *> &waitables, AuUInt32 uFlags, AuUInt64 uTimeout = 0);

    static inline bool WaitForShared(const AuList<AuSPtr<IWaitable>> &pWaitables, AuUInt32 uFlags, AuUInt64 uTimeout)
    {
        AU_DEBUG_MEMCRUNCH;
        AuList<IWaitable *> waitables;
        
        waitables.reserve(pWaitables.size());
        for (const auto &pIWaitable : pWaitables)
        {
            waitables.push_back(pIWaitable.get());
        }

        return WaitFor(waitables, uFlags, uTimeout);
    }

    /// legacy api (~3 years old, relative to 2023)
    /// @deprecated
    static inline bool WaitFor(const AuList<IWaitable *> &waitables, AuUInt64 uTimeout)
    {
        return WaitFor(waitables, 0, uTimeout);
    }

    /// legacy api (~3 years old, relative to 2023)
    /// @deprecated
    static inline bool WaitFor(IWaitable *pWaitable, AuUInt64 uTimeoutMS)
    {
        return WaitForAbsNS(pWaitable, uTimeoutMS ? AuMSToNS<AuUInt64>(uTimeoutMS) + Time::SteadyClockNS() : 0);
    }
}