// Copyright 2016 Brian Smith.

//

// Permission to use, copy, modify, and/or distribute this software for any

// purpose with or without fee is hereby granted, provided that the above

// copyright notice and this permission notice appear in all copies.

//

// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES

// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY

// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION

// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN

// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

/// A witness indicating that CPU features have been detected and cached.

///

/// TODO: Eventually all feature detection logic should be done through

/// functions that accept a `Features` parameter, to guarantee that nothing

/// tries to read the cached values before they are written.

///

/// This is a zero-sized type so that it can be "stored" wherever convenient.

#[derive(Copy, Clone)]

pub(crate) struct Features(());

#[inline(always)]

pub(crate) fn features() -> Features {

    // We don't do runtime feature detection on aarch64-apple-* as all AAarch64

    // features we use are available on every device since the first devices.

    #[cfg(any(

        target_arch = "x86",

        target_arch = "x86_64",

        all(

            any(target_arch = "aarch64", target_arch = "arm"),

            any(

                target_os = "android",

                target_os = "fuchsia",

                target_os = "linux",

                target_os = "windows"

            )

        )

    ))]

    {

        static INIT: spin::Once<()> = spin::Once::new();

        let () = INIT.call_once(|| {

            #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]

            {

                prefixed_extern! {

                    fn OPENSSL_cpuid_setup();

                }

                unsafe {

                    OPENSSL_cpuid_setup();

                }

            }

            #[cfg(any(target_arch = "aarch64", target_arch = "arm"))]

            {

                unsafe { arm::initialize_OPENSSL_armcap_P() }

            }

        });

    }

    Features(())

}

pub mod arm;

pub mod intel;