#pragma once
// ke_spinlock.h - spinlock for short, non-sleeping critical sections
// Uses MSVC interlocked intrinsics. Never hold across a scheduling boundary.
#include <stdint.h>
#include <intrin.h>

typedef struct SPINLOCK {
    volatile long Locked;
} SPINLOCK;

#define SPINLOCK_INIT  { 0 }

// Issue 1 Fix: Save EFLAGS, disable interrupts, and return old flags.
static __forceinline uintptr_t KeAcquireSpinlock(SPINLOCK* sl) {
    uintptr_t flags = __readeflags();
    _disable();
    while (_InterlockedCompareExchange(&sl->Locked, 1, 0) != 0)
        _mm_pause();
    return flags;
}

// Issue 1 Fix: Restore EFLAGS upon release.
static __forceinline void KeReleaseSpinlock(SPINLOCK* sl, uintptr_t flags) {
    _InterlockedExchange(&sl->Locked, 0);
    __writeeflags(flags);
}

static __forceinline int KeTryAcquireSpinlock(SPINLOCK* sl, uintptr_t* outFlags) {
    uintptr_t flags = __readeflags();
    _disable();
    if (_InterlockedCompareExchange(&sl->Locked, 1, 0) == 0) {
        *outFlags = flags;
        return 1;
    }
    __writeeflags(flags);
    return 0;
}