#![cfg_attr(docsrs, feature(doc_cfg))]

#![doc = include_str!("../README.md")]

// @@ begin lint list maintained by maint/add_warning @@

#![allow(renamed_and_removed_lints)] // @@REMOVE_WHEN(ci_arti_stable)

#![allow(unknown_lints)] // @@REMOVE_WHEN(ci_arti_nightly)

#![warn(missing_docs)]

#![warn(noop_method_call)]

#![warn(unreachable_pub)]

#![warn(clippy::all)]

#![deny(clippy::await_holding_lock)]

#![deny(clippy::cargo_common_metadata)]

#![deny(clippy::cast_lossless)]

#![deny(clippy::checked_conversions)]

#![allow(clippy::cognitive_complexity)] // See arti#2556

#![deny(clippy::debug_assert_with_mut_call)]

#![deny(clippy::exhaustive_enums)]

#![deny(clippy::exhaustive_structs)]

#![deny(clippy::expl_impl_clone_on_copy)]

#![deny(clippy::fallible_impl_from)]

#![deny(clippy::implicit_clone)]

#![deny(clippy::large_stack_arrays)]

#![warn(clippy::manual_ok_or)]

#![deny(clippy::missing_docs_in_private_items)]

#![warn(clippy::needless_borrow)]

#![warn(clippy::needless_pass_by_value)]

#![warn(clippy::option_option)]

#![warn(clippy::or_fun_call)]

#![deny(clippy::print_stderr)]

#![deny(clippy::print_stdout)]

#![warn(clippy::rc_buffer)]

#![deny(clippy::ref_option_ref)]

#![warn(clippy::semicolon_if_nothing_returned)]

#![warn(clippy::trait_duplication_in_bounds)]

#![deny(clippy::unchecked_time_subtraction)]

#![deny(clippy::unnecessary_wraps)]

#![warn(clippy::unseparated_literal_suffix)]

#![deny(clippy::unwrap_used)]

#![deny(clippy::mod_module_files)]

#![allow(clippy::let_unit_value)] // This can reasonably be done for explicitness

#![allow(clippy::uninlined_format_args)]

#![allow(clippy::significant_drop_in_scrutinee)] // arti/-/merge_requests/588/#note_2812945

#![allow(clippy::result_large_err)] // temporary workaround for arti#587

#![allow(clippy::needless_raw_string_hashes)] // complained-about code is fine, often best

#![allow(clippy::needless_lifetimes)] // See arti#1765

#![allow(mismatched_lifetime_syntaxes)] // temporary workaround for arti#2060

#![allow(clippy::collapsible_if)] // See arti#2342

#![deny(clippy::unused_async)]

#![deny(clippy::string_slice)] // See arti#2571

#![allow(recursion_depth_exceeding_limit)] // arti#2715, rust/issues/159228

//! <!-- @@ end lint list maintained by maint/add_warning @@ -->

mod compiler;

mod constraints;

mod err;

mod generator;

mod program;

mod rand;

mod register;

mod scheduler;

mod siphash;

use crate::compiler::{Architecture, Executable};

use crate::program::Program;

use rand_core::Rng;

pub use crate::err::{CompilerError, Error};

pub use crate::rand::SipRand;

pub use crate::siphash::SipState;

/// Option for selecting a HashX runtime

#[derive(Default, Debug, Copy, Clone, Eq, PartialEq)]

#[non_exhaustive]

pub enum RuntimeOption {

    /// Choose the interpreted runtime, without trying the compiler at all.

    InterpretOnly,

    /// Choose the compiled runtime only, and fail if it experiences any errors.

    CompileOnly,

    /// Always try the compiler first but fall back to the interpreter on error.

    /// (This is the default)

    #[default]

    TryCompile,

}

/// Effective HashX runtime for a constructed program

#[derive(Debug, Copy, Clone, Eq, PartialEq)]

#[non_exhaustive]

pub enum Runtime {

    /// The interpreted runtime is active.

    Interpret,

    /// The compiled runtime is active.

    Compiled,

}

/// Pre-built hash program that can be rapidly computed with different inputs

///

/// The program and initial state representation are not specified in this

/// public interface, but [`std::fmt::Debug`] can describe program internals.

#[derive(Debug)]

pub struct HashX {

    /// Keys used to generate an initial register state from the hash input

    ///

    /// Half of the key material generated from seed bytes go into the random

    /// program generator, and the other half are saved here for use in each

    /// hash invocation.

    register_key: SipState,

    /// A prepared randomly generated hash program

    ///

    /// In compiled runtimes this will be executable code, and in the

    /// interpreter it's a list of instructions. There is no stable API for

    /// program information, but the Debug trait will list programs in either

    /// format.

    program: RuntimeProgram,

}

/// Combination of [`Runtime`] and the actual program info used by that runtime

///

/// All variants of [`RuntimeProgram`] use some kind of inner heap allocation

/// to store the program data.

#[derive(Debug)]

enum RuntimeProgram {

    /// Select the interpreted runtime, and hold a Program for it to run.

    Interpret(Program),

    /// Select the compiled runtime, and hold an executable code page.

    Compiled(Executable),

}

impl HashX {

    /// The maximum available output size for [`Self::hash_to_bytes()`]

    pub const FULL_SIZE: usize = 32;

    /// Generate a new hash function with the supplied seed.

    /// Check which actual program runtime is in effect.

    ///

    /// By default we try to generate code at runtime to accelerate the hash

    /// function, but we fall back to an interpreter if this fails. The compiler

    /// can be disabled entirely using [`RuntimeOption::InterpretOnly`] and

    /// [`HashXBuilder`].

        }

    /// Calculate the first 64-bit word of the hash, without converting to bytes.

    /// Calculate the hash function at its full output width, returning a fixed

    /// size byte array.

    /// Common setup for hashes with any output format

    #[inline(always)]

        }

}

/// Builder for creating [`HashX`] instances with custom settings

#[derive(Default, Debug, Clone, Eq, PartialEq)]

pub struct HashXBuilder {

    /// Current runtime() setting for this builder

    runtime: RuntimeOption,

}

impl HashXBuilder {

    /// Create a new [`HashXBuilder`] with default settings.

    ///

    /// Immediately calling [`Self::build()`] would be equivalent to using

    /// [`HashX::new()`].

    /// Select a new [`RuntimeOption`].

    /// Build a [`HashX`] instance with a seed and the selected options.

    /// Build a [`HashX`] instance from an arbitrary [`Rng`] and

    /// a [`SipState`] key used for initializing the register file.

    /// Build a [`HashX`] instance from an already-generated [`Program`] and

    /// [`SipState`] key.

    ///

    /// The program is either stored as-is or compiled, depending on the current

    /// [`RuntimeOption`]. Requires a program as well as a [`SipState`] to be

    /// used for initializing the register file.

        Ok(HashX {

                RuntimeOption::CompileOnly => {

                }

                },

            },

        })

}