Implement WaitOnAddress API on Linux (rev 2)

wait_wakeonaddress.c

static bool WaitOnAddress(volatile void *Address, void *CompareAddress, size_t AddressSize, uint32_t Milliseconds) {
    struct timespec ts;
    struct timespec *timeout = NULL;

    if (Milliseconds != UINT_MAX) {
        ts.tv_sec = Milliseconds / 1000;
        ts.tv_nsec = (Milliseconds % 1000) * 1000000;
        timeout = &ts;
    }

    uint32_t shared_value = atomic_load((atomic_uintptr_t*)Address);
    uint32_t expected_value = *(uint32_t*)CompareAddress;

    if (shared_value == expected_value) {
        int result = futex((uint32_t*)Address, FUTEX_WAIT_PRIVATE, expected_value, timeout, NULL, 0);
        if (result == -1) {
            if (errno == ETIMEDOUT) {
                return false;
            } else {
                perror("futex wait (WaitOnAddress)");
                return false;
            }
        }
        return true;
    } else {
        return false;
    }
}

static void WakeByAddressAll(void *Address) {
    if (futex((uint32_t*)Address, FUTEX_WAKE_PRIVATE, 128, NULL, NULL, 0) == -1) {
        perror("futex wake (WakeByAddressAll)");
    }
}

static void WakeByAddressSingle(void *Address) {
    if (futex((uint32_t*)Address, FUTEX_WAKE_PRIVATE, 1, NULL, NULL, 0) == -1) {
        perror("futex wake (WakeByAddressSingle)");
    }
}