| // Copyright 2014 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| //! Platform-independent platform abstraction |
| //! |
| //! This is the platform-independent portion of the standard library's |
| //! platform abstraction layer, whereas `std::sys` is the |
| //! platform-specific portion. |
| //! |
| //! The relationship between `std::sys_common`, `std::sys` and the |
| //! rest of `std` is complex, with dependencies going in all |
| //! directions: `std` depending on `sys_common`, `sys_common` |
| //! depending on `sys`, and `sys` depending on `sys_common` and `std`. |
| //! Ideally `sys_common` would be split into two and the dependencies |
| //! between them all would form a dag, facilitating the extraction of |
| //! `std::sys` from the standard library. |
| |
| #![allow(missing_docs)] |
| #![allow(missing_debug_implementations)] |
| |
| use sync::Once; |
| use sys; |
| |
| pub mod at_exit_imp; |
| #[cfg(feature = "backtrace")] |
| pub mod backtrace; |
| pub mod condvar; |
| pub mod io; |
| pub mod mutex; |
| pub mod poison; |
| pub mod remutex; |
| pub mod rwlock; |
| pub mod thread; |
| pub mod thread_info; |
| pub mod thread_local; |
| pub mod util; |
| pub mod wtf8; |
| pub mod bytestring; |
| pub mod process; |
| |
| cfg_if! { |
| if #[cfg(any(target_os = "cloudabi", target_os = "l4re", target_os = "redox"))] { |
| pub use sys::net; |
| } else if #[cfg(all(target_arch = "wasm32", not(target_os = "emscripten")))] { |
| pub use sys::net; |
| } else { |
| pub mod net; |
| } |
| } |
| |
| #[cfg(feature = "backtrace")] |
| #[cfg(any(all(unix, not(target_os = "emscripten")), |
| all(windows, target_env = "gnu"), |
| target_os = "redox"))] |
| pub mod gnu; |
| |
| // common error constructors |
| |
| /// A trait for viewing representations from std types |
| #[doc(hidden)] |
| pub trait AsInner<Inner: ?Sized> { |
| fn as_inner(&self) -> &Inner; |
| } |
| |
| /// A trait for viewing representations from std types |
| #[doc(hidden)] |
| pub trait AsInnerMut<Inner: ?Sized> { |
| fn as_inner_mut(&mut self) -> &mut Inner; |
| } |
| |
| /// A trait for extracting representations from std types |
| #[doc(hidden)] |
| pub trait IntoInner<Inner> { |
| fn into_inner(self) -> Inner; |
| } |
| |
| /// A trait for creating std types from internal representations |
| #[doc(hidden)] |
| pub trait FromInner<Inner> { |
| fn from_inner(inner: Inner) -> Self; |
| } |
| |
| /// Enqueues a procedure to run when the main thread exits. |
| /// |
| /// Currently these closures are only run once the main *Rust* thread exits. |
| /// Once the `at_exit` handlers begin running, more may be enqueued, but not |
| /// infinitely so. Eventually a handler registration will be forced to fail. |
| /// |
| /// Returns `Ok` if the handler was successfully registered, meaning that the |
| /// closure will be run once the main thread exits. Returns `Err` to indicate |
| /// that the closure could not be registered, meaning that it is not scheduled |
| /// to be run. |
| pub fn at_exit<F: FnOnce() + Send + 'static>(f: F) -> Result<(), ()> { |
| if at_exit_imp::push(Box::new(f)) {Ok(())} else {Err(())} |
| } |
| |
| macro_rules! rtabort { |
| ($($t:tt)*) => (::sys_common::util::abort(format_args!($($t)*))) |
| } |
| |
| /// One-time runtime cleanup. |
| pub fn cleanup() { |
| static CLEANUP: Once = Once::new(); |
| CLEANUP.call_once(|| unsafe { |
| sys::args::cleanup(); |
| sys::stack_overflow::cleanup(); |
| at_exit_imp::cleanup(); |
| }); |
| } |
| |
| // Computes (value*numer)/denom without overflow, as long as both |
| // (numer*denom) and the overall result fit into i64 (which is the case |
| // for our time conversions). |
| #[allow(dead_code)] // not used on all platforms |
| pub fn mul_div_u64(value: u64, numer: u64, denom: u64) -> u64 { |
| let q = value / denom; |
| let r = value % denom; |
| // Decompose value as (value/denom*denom + value%denom), |
| // substitute into (value*numer)/denom and simplify. |
| // r < denom, so (denom*numer) is the upper bound of (r*numer) |
| q * numer + r * numer / denom |
| } |
| |
| #[test] |
| fn test_muldiv() { |
| assert_eq!(mul_div_u64( 1_000_000_000_001, 1_000_000_000, 1_000_000), |
| 1_000_000_000_001_000); |
| } |