From 47ea358ddc1bc37b809f9f5b893a6b099cbb262b Mon Sep 17 00:00:00 2001 From: Daniel Mueller Date: Mon, 12 Aug 2019 22:23:33 -0700 Subject: Update nitrokey crate to 0.4.0-alpha.3 This change updates the version of the nitrokey crate that we use to 0.4.0-alpha.3. This version is the supposedly last pre-release before 0.4.0, with no further major anticipated changes. In order to integrate with this new version we have to adjust the way we connect to a Nitrokey device by funneling those connection requests through a global manager object. The rationale behind that step being that the underlying libnitrokey actually cannot handle access of multiple devices at the same time, and so the manager object is used to prevent accidental wrong concurrent usage. Because a device object now effectively keeps a reference to the manager, we need to provide an additional lifetime to that and derived objects. Lastly, the use of a manager is also the reason why the tests had to be adjusted to no longer accept device objects in their signatures, but only the respective model for which to invoke the test. That is required because, as elaborated earlier on, having a device object implies having taken a reference to a manager (in that case owned by nitrokey-test), and that reference clashes with the nitrocli code itself attempting to take the manager. We side step this problem by merely accepting a Model object, which can be passed around independently of the manager itself, meaning that nitrokey-test does not need to hold such a reference while the test is run. Import subrepo nitrokey/:nitrokey at f150d59410eefdec2ae69b2422906a3d1d88aa07 Import subrepo nitrokey-sys/:nitrokey-sys at 8695e2c762807e033a86c8d03974b686d20cdd72 Import subrepo lazy-static/:lazy-static at b4b2b16aaa79dd7548e288455a0dbe4065bf4e1a --- lazy-static/src/core_lazy.rs | 31 ++++++ lazy-static/src/inline_lazy.rs | 65 +++++++++++++ lazy-static/src/lib.rs | 212 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 308 insertions(+) create mode 100644 lazy-static/src/core_lazy.rs create mode 100644 lazy-static/src/inline_lazy.rs create mode 100644 lazy-static/src/lib.rs (limited to 'lazy-static/src') diff --git a/lazy-static/src/core_lazy.rs b/lazy-static/src/core_lazy.rs new file mode 100644 index 0000000..b66c3e0 --- /dev/null +++ b/lazy-static/src/core_lazy.rs @@ -0,0 +1,31 @@ +// Copyright 2016 lazy-static.rs Developers +// +// Licensed under the Apache License, Version 2.0, or the MIT license , at your option. This file may not be +// copied, modified, or distributed except according to those terms. + +extern crate spin; + +use self::spin::Once; + +pub struct Lazy(Once); + +impl Lazy { + pub const INIT: Self = Lazy(Once::INIT); + + #[inline(always)] + pub fn get(&'static self, builder: F) -> &T + where F: FnOnce() -> T + { + self.0.call_once(builder) + } +} + +#[macro_export] +#[doc(hidden)] +macro_rules! __lazy_static_create { + ($NAME:ident, $T:ty) => { + static $NAME: $crate::lazy::Lazy<$T> = $crate::lazy::Lazy::INIT; + } +} diff --git a/lazy-static/src/inline_lazy.rs b/lazy-static/src/inline_lazy.rs new file mode 100644 index 0000000..268dd45 --- /dev/null +++ b/lazy-static/src/inline_lazy.rs @@ -0,0 +1,65 @@ +// Copyright 2016 lazy-static.rs Developers +// +// Licensed under the Apache License, Version 2.0, or the MIT license , at your option. This file may not be +// copied, modified, or distributed except according to those terms. + +extern crate core; +extern crate std; + +use self::std::prelude::v1::*; +use self::std::cell::Cell; +use self::std::sync::Once; +pub use self::std::sync::ONCE_INIT; + +// FIXME: Replace Option with MaybeInitialized +pub struct Lazy(Cell>, Once); + +impl Lazy { + pub const INIT: Self = Lazy(Cell::new(None), ONCE_INIT); + + #[inline(always)] + pub fn get(&'static self, f: F) -> &T + where + F: FnOnce() -> T, + { + self.1.call_once(|| { + self.0.set(Some(f())); + }); + + // `self.0` is guaranteed to be `Some` by this point + // The `Once` will catch and propegate panics + unsafe { + match *self.0.as_ptr() { + Some(ref x) => x, + None => { + debug_assert!(false, "attempted to derefence an uninitialized lazy static. This is a bug"); + + unreachable_unchecked() + }, + } + } + } +} + +unsafe impl Sync for Lazy {} + +#[macro_export] +#[doc(hidden)] +macro_rules! __lazy_static_create { + ($NAME:ident, $T:ty) => { + static $NAME: $crate::lazy::Lazy<$T> = $crate::lazy::Lazy::INIT; + }; +} + +/// Polyfill for std::hint::unreachable_unchecked. There currently exists a +/// [crate](https://docs.rs/unreachable) for an equivalent to std::hint::unreachable_unchecked, but +/// lazy_static currently doesn't include any runtime dependencies and we've chosen to include this +/// short polyfill rather than include a new crate in every consumer's build. +/// +/// This should be replaced by std's version when lazy_static starts to require at least Rust 1.27. +unsafe fn unreachable_unchecked() -> ! { + enum Void {} + match std::mem::uninitialized::() {} +} diff --git a/lazy-static/src/lib.rs b/lazy-static/src/lib.rs new file mode 100644 index 0000000..42dc405 --- /dev/null +++ b/lazy-static/src/lib.rs @@ -0,0 +1,212 @@ +// Copyright 2016 lazy-static.rs Developers +// +// Licensed under the Apache License, Version 2.0, or the MIT license , at your option. This file may not be +// copied, modified, or distributed except according to those terms. + +/*! +A macro for declaring lazily evaluated statics. + +Using this macro, it is possible to have `static`s that require code to be +executed at runtime in order to be initialized. +This includes anything requiring heap allocations, like vectors or hash maps, +as well as anything that requires function calls to be computed. + +# Syntax + +```ignore +lazy_static! { + [pub] static ref NAME_1: TYPE_1 = EXPR_1; + [pub] static ref NAME_2: TYPE_2 = EXPR_2; + ... + [pub] static ref NAME_N: TYPE_N = EXPR_N; +} +``` + +Attributes (including doc comments) are supported as well: + +```rust +# #[macro_use] +# extern crate lazy_static; +# fn main() { +lazy_static! { + /// This is an example for using doc comment attributes + static ref EXAMPLE: u8 = 42; +} +# } +``` + +# Semantics + +For a given `static ref NAME: TYPE = EXPR;`, the macro generates a unique type that +implements `Deref` and stores it in a static with name `NAME`. (Attributes end up +attaching to this type.) + +On first deref, `EXPR` gets evaluated and stored internally, such that all further derefs +can return a reference to the same object. Note that this can lead to deadlocks +if you have multiple lazy statics that depend on each other in their initialization. + +Apart from the lazy initialization, the resulting "static ref" variables +have generally the same properties as regular "static" variables: + +- Any type in them needs to fulfill the `Sync` trait. +- If the type has a destructor, then it will not run when the process exits. + +# Example + +Using the macro: + +```rust +#[macro_use] +extern crate lazy_static; + +use std::collections::HashMap; + +lazy_static! { + static ref HASHMAP: HashMap = { + let mut m = HashMap::new(); + m.insert(0, "foo"); + m.insert(1, "bar"); + m.insert(2, "baz"); + m + }; + static ref COUNT: usize = HASHMAP.len(); + static ref NUMBER: u32 = times_two(21); +} + +fn times_two(n: u32) -> u32 { n * 2 } + +fn main() { + println!("The map has {} entries.", *COUNT); + println!("The entry for `0` is \"{}\".", HASHMAP.get(&0).unwrap()); + println!("A expensive calculation on a static results in: {}.", *NUMBER); +} +``` + +# Implementation details + +The `Deref` implementation uses a hidden static variable that is guarded by an atomic check on each access. + +# Cargo features + +This crate provides two cargo features: + +- `nightly`: This uses unstable language features only available on the nightly release channel for a more optimal implementation. In practice this currently means avoiding a heap allocation per static. This feature might get deprecated at a later point once all relevant optimizations are usable from stable. +- `spin_no_std` (implies `nightly`): This allows using this crate in a no-std environment, by depending on the standalone `spin` crate. + +Both features depend on unstable language features, which means +no guarantees can be made about them in regard to SemVer stability. + +*/ + +#![doc(html_root_url = "https://docs.rs/lazy_static/1.2.0")] +#![no_std] + +#[cfg(not(feature = "spin_no_std"))] +#[path="inline_lazy.rs"] +#[doc(hidden)] +pub mod lazy; + +#[cfg(feature = "spin_no_std")] +#[path="core_lazy.rs"] +#[doc(hidden)] +pub mod lazy; + +#[doc(hidden)] +pub use core::ops::Deref as __Deref; + +#[macro_export(local_inner_macros)] +#[doc(hidden)] +macro_rules! __lazy_static_internal { + // optional visibility restrictions are wrapped in `()` to allow for + // explicitly passing otherwise implicit information about private items + ($(#[$attr:meta])* ($($vis:tt)*) static ref $N:ident : $T:ty = $e:expr; $($t:tt)*) => { + __lazy_static_internal!(@MAKE TY, $(#[$attr])*, ($($vis)*), $N); + __lazy_static_internal!(@TAIL, $N : $T = $e); + lazy_static!($($t)*); + }; + (@TAIL, $N:ident : $T:ty = $e:expr) => { + impl $crate::__Deref for $N { + type Target = $T; + fn deref(&self) -> &$T { + #[inline(always)] + fn __static_ref_initialize() -> $T { $e } + + #[inline(always)] + fn __stability() -> &'static $T { + __lazy_static_create!(LAZY, $T); + LAZY.get(__static_ref_initialize) + } + __stability() + } + } + impl $crate::LazyStatic for $N { + fn initialize(lazy: &Self) { + let _ = &**lazy; + } + } + }; + // `vis` is wrapped in `()` to prevent parsing ambiguity + (@MAKE TY, $(#[$attr:meta])*, ($($vis:tt)*), $N:ident) => { + #[allow(missing_copy_implementations)] + #[allow(non_camel_case_types)] + #[allow(dead_code)] + $(#[$attr])* + $($vis)* struct $N {__private_field: ()} + #[doc(hidden)] + $($vis)* static $N: $N = $N {__private_field: ()}; + }; + () => () +} + +#[macro_export(local_inner_macros)] +macro_rules! lazy_static { + ($(#[$attr:meta])* static ref $N:ident : $T:ty = $e:expr; $($t:tt)*) => { + // use `()` to explicitly forward the information about private items + __lazy_static_internal!($(#[$attr])* () static ref $N : $T = $e; $($t)*); + }; + ($(#[$attr:meta])* pub static ref $N:ident : $T:ty = $e:expr; $($t:tt)*) => { + __lazy_static_internal!($(#[$attr])* (pub) static ref $N : $T = $e; $($t)*); + }; + ($(#[$attr:meta])* pub ($($vis:tt)+) static ref $N:ident : $T:ty = $e:expr; $($t:tt)*) => { + __lazy_static_internal!($(#[$attr])* (pub ($($vis)+)) static ref $N : $T = $e; $($t)*); + }; + () => () +} + +/// Support trait for enabling a few common operation on lazy static values. +/// +/// This is implemented by each defined lazy static, and +/// used by the free functions in this crate. +pub trait LazyStatic { + #[doc(hidden)] + fn initialize(lazy: &Self); +} + +/// Takes a shared reference to a lazy static and initializes +/// it if it has not been already. +/// +/// This can be used to control the initialization point of a lazy static. +/// +/// Example: +/// +/// ```rust +/// #[macro_use] +/// extern crate lazy_static; +/// +/// lazy_static! { +/// static ref BUFFER: Vec = (0..65537).collect(); +/// } +/// +/// fn main() { +/// lazy_static::initialize(&BUFFER); +/// +/// // ... +/// work_with_initialized_data(&BUFFER); +/// } +/// # fn work_with_initialized_data(_: &[u8]) {} +/// ``` +pub fn initialize(lazy: &T) { + LazyStatic::initialize(lazy); +} -- cgit v1.2.3