SDL

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/*
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  Simple DirectMedia Layer
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  Copyright (C) 1997-2024 Sam Lantinga <slouken@libsdl.org>
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  This software is provided 'as-is', without any express or implied
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  warranty.  In no event will the authors be held liable for any damages
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  arising from the use of this software.
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  Permission is granted to anyone to use this software for any purpose,
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  including commercial applications, and to alter it and redistribute it
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  freely, subject to the following restrictions:
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  1. The origin of this software must not be misrepresented; you must not
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     claim that you wrote the original software. If you use this software
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     in a product, an acknowledgment in the product documentation would be
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     appreciated but is not required.
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  2. Altered source versions must be plainly marked as such, and must not be
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     misrepresented as being the original software.
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  3. This notice may not be removed or altered from any source distribution.
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*/
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#include "SDL_internal.h"
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#ifdef SDL_TIMER_WINDOWS
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#include "../../core/windows/SDL_windows.h"
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#ifdef CREATE_WAITABLE_TIMER_HIGH_RESOLUTION
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static void SDL_CleanupWaitableTimer(void *timer)
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{
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    CloseHandle(timer);
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}
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HANDLE SDL_GetWaitableTimer(void)
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{
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    static SDL_TLSID TLS_timer_handle;
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    HANDLE timer;
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    timer = SDL_GetTLS(&TLS_timer_handle);
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    if (!timer) {
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        timer = CreateWaitableTimerExW(NULL, NULL, CREATE_WAITABLE_TIMER_HIGH_RESOLUTION, TIMER_ALL_ACCESS);
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        if (timer) {
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            SDL_SetTLS(&TLS_timer_handle, timer, SDL_CleanupWaitableTimer);
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        }
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    }
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    return timer;
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}
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#endif // CREATE_WAITABLE_TIMER_HIGH_RESOLUTION
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Uint64 SDL_GetPerformanceCounter(void)
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{
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    LARGE_INTEGER counter;
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    const BOOL rc = QueryPerformanceCounter(&counter);
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    SDL_assert(rc != 0); // this should _never_ fail if you're on XP or later.
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    return (Uint64)counter.QuadPart;
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}
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Uint64 SDL_GetPerformanceFrequency(void)
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{
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    LARGE_INTEGER frequency;
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    const BOOL rc = QueryPerformanceFrequency(&frequency);
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    SDL_assert(rc != 0); // this should _never_ fail if you're on XP or later.
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    return (Uint64)frequency.QuadPart;
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}
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void SDL_SYS_DelayNS(Uint64 ns)
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{
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    /* CREATE_WAITABLE_TIMER_HIGH_RESOLUTION flag was added in Windows 10 version 1803.
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     *
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     * Sleep() is not publicly available to apps in early versions of WinRT.
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     *
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     * Visual C++ 2013 Update 4 re-introduced Sleep() for Windows 8.1 and
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     * Windows Phone 8.1.
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     *
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     * Use the compiler version to determine availability.
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     *
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     * NOTE #1: _MSC_FULL_VER == 180030723 for Visual C++ 2013 Update 3.
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     * NOTE #2: Visual C++ 2013, when compiling for Windows 8.0 and
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     *    Windows Phone 8.0, uses the Visual C++ 2012 compiler to build
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     *    apps and libraries.
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     */
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#ifdef CREATE_WAITABLE_TIMER_HIGH_RESOLUTION
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    HANDLE timer = SDL_GetWaitableTimer();
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    if (timer) {
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        LARGE_INTEGER due_time;
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        due_time.QuadPart = -((LONGLONG)ns / 100);
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        if (SetWaitableTimerEx(timer, &due_time, 0, NULL, NULL, NULL, 0)) {
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            WaitForSingleObject(timer, INFINITE);
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        }
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        return;
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    }
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#endif
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    {
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        const Uint64 max_delay = 0xffffffffLL * SDL_NS_PER_MS;
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        if (ns > max_delay) {
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            ns = max_delay;
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        }
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#if defined(SDL_PLATFORM_WINRT) && defined(_MSC_FULL_VER) && (_MSC_FULL_VER <= 180030723)
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        static HANDLE mutex = 0;
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        if (!mutex) {
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            mutex = CreateEventEx(0, 0, 0, EVENT_ALL_ACCESS);
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        }
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        WaitForSingleObjectEx(mutex, (DWORD)SDL_NS_TO_MS(ns), FALSE);
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#else
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        Sleep((DWORD)SDL_NS_TO_MS(ns));
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#endif
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    }
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}
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#endif // SDL_TIMER_WINDOWS
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