]>
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1 //! Platform-independent platform abstraction
3 //! This is the platform-independent portion of the standard library's
4 //! platform abstraction layer, whereas `std::sys` is the
5 //! platform-specific portion.
7 //! The relationship between `std::sys_common`, `std::sys` and the
8 //! rest of `std` is complex, with dependencies going in all
9 //! directions: `std` depending on `sys_common`, `sys_common`
10 //! depending on `sys`, and `sys` depending on `sys_common` and `std`.
11 //! This is because `sys_common` not only contains platform-independent code,
12 //! but also code that is shared between the different platforms in `sys`.
13 //! Ideally all that shared code should be moved to `sys::common`,
14 //! and the dependencies between `std`, `sys_common` and `sys` all would form a dag.
15 //! Progress on this is tracked in #84187.
17 #![allow(missing_docs)]
18 #![allow(missing_debug_implementations)]
34 pub mod thread_local_dtor
;
35 pub mod thread_local_key
;
36 pub mod thread_parker
;
40 if #[cfg(any(target_os = "l4re",
42 feature
= "restricted-std",
43 all(target_arch
= "wasm32", not(target_os
= "emscripten")),
44 all(target_vendor
= "fortanix", target_env
= "sgx")))] {
45 pub use crate::sys
::net
;
51 // common error constructors
53 /// A trait for viewing representations from std types
55 pub trait AsInner
<Inner
: ?Sized
> {
56 fn as_inner(&self) -> &Inner
;
59 /// A trait for viewing representations from std types
61 pub trait AsInnerMut
<Inner
: ?Sized
> {
62 fn as_inner_mut(&mut self) -> &mut Inner
;
65 /// A trait for extracting representations from std types
67 pub trait IntoInner
<Inner
> {
68 fn into_inner(self) -> Inner
;
71 /// A trait for creating std types from internal representations
73 pub trait FromInner
<Inner
> {
74 fn from_inner(inner
: Inner
) -> Self;
77 // Computes (value*numer)/denom without overflow, as long as both
78 // (numer*denom) and the overall result fit into i64 (which is the case
79 // for our time conversions).
80 #[allow(dead_code)] // not used on all platforms
81 pub fn mul_div_u64(value
: u64, numer
: u64, denom
: u64) -> u64 {
82 let q
= value
/ denom
;
83 let r
= value
% denom
;
84 // Decompose value as (value/denom*denom + value%denom),
85 // substitute into (value*numer)/denom and simplify.
86 // r < denom, so (denom*numer) is the upper bound of (r*numer)
87 q
* numer
+ r
* numer
/ denom