1//! Platform-dependent platform abstraction.
2//!
3//! The `std::sys` module is the abstracted interface through which
4//! `std` talks to the underlying operating system. It has different
5//! implementations for different operating system families, today
6//! just Unix and Windows, and initial support for Redox.
7//!
8//! The centralization of platform-specific code in this module is
9//! enforced by the "platform abstraction layer" tidy script in
10//! `tools/tidy/src/pal.rs`.
11//!
12//! This module is closely related to the platform-independent system
13//! integration code in `std::sys_common`. See that module's
14//! documentation for details.
15//!
16//! In the future it would be desirable for the independent
17//! implementations of this module to be extracted to their own crates
18//! that `std` can link to, thus enabling their implementation
19//! out-of-tree via crate replacement. Though due to the complex
20//! inter-dependencies within `std` that will be a challenging goal to
21//! achieve.
22
23#![allow(missing_debug_implementations)]
24
25pub mod common;
26
27cfg_if::cfg_if! {
28 if #[cfg(unix)] {
29 mod unix;
30 pub use self::unix::*;
31 } else if #[cfg(windows)] {
32 mod windows;
33 pub use self::windows::*;
34 } else if #[cfg(target_os = "solid_asp3")] {
35 mod solid;
36 pub use self::solid::*;
37 } else if #[cfg(target_os = "hermit")] {
38 mod hermit;
39 pub use self::hermit::*;
40 } else if #[cfg(all(target_os = "wasi", target_env = "p2"))] {
41 mod wasip2;
42 pub use self::wasip2::*;
43 } else if #[cfg(target_os = "wasi")] {
44 mod wasi;
45 pub use self::wasi::*;
46 } else if #[cfg(target_family = "wasm")] {
47 mod wasm;
48 pub use self::wasm::*;
49 } else if #[cfg(target_os = "xous")] {
50 mod xous;
51 pub use self::xous::*;
52 } else if #[cfg(target_os = "uefi")] {
53 mod uefi;
54 pub use self::uefi::*;
55 } else if #[cfg(all(target_vendor = "fortanix", target_env = "sgx"))] {
56 mod sgx;
57 pub use self::sgx::*;
58 } else if #[cfg(target_os = "teeos")] {
59 mod teeos;
60 pub use self::teeos::*;
61 } else if #[cfg(target_os = "zkvm")] {
62 mod zkvm;
63 pub use self::zkvm::*;
64 } else {
65 mod unsupported;
66 pub use self::unsupported::*;
67 }
68}
69
70cfg_if::cfg_if! {
71 // Fuchsia components default to full backtrace.
72 if #[cfg(target_os = "fuchsia")] {
73 pub const FULL_BACKTRACE_DEFAULT: bool = true;
74 } else {
75 pub const FULL_BACKTRACE_DEFAULT: bool = false;
76 }
77}
78
79#[cfg(not(test))]
80cfg_if::cfg_if! {
81 if #[cfg(target_os = "android")] {
82 pub use self::android::log2f32;
83 pub use self::android::log2f64;
84 } else {
85 #[inline]
86 pub fn log2f32(n: f32) -> f32 {
87 unsafe { crate::intrinsics::log2f32(n) }
88 }
89
90 #[inline]
91 pub fn log2f64(n: f64) -> f64 {
92 unsafe { crate::intrinsics::log2f64(n) }
93 }
94 }
95}
96
97// Solaris/Illumos requires a wrapper around log, log2, and log10 functions
98// because of their non-standard behavior (e.g., log(-n) returns -Inf instead
99// of expected NaN).
100#[cfg(not(test))]
101#[cfg(any(target_os = "solaris", target_os = "illumos"))]
102#[inline]
103pub fn log_wrapper<F: Fn(f64) -> f64>(n: f64, log_fn: F) -> f64 {
104 if n.is_finite() {
105 if n > 0.0 {
106 log_fn(n)
107 } else if n == 0.0 {
108 f64::NEG_INFINITY // log(0) = -Inf
109 } else {
110 f64::NAN // log(-n) = NaN
111 }
112 } else if n.is_nan() {
113 n // log(NaN) = NaN
114 } else if n > 0.0 {
115 n // log(Inf) = Inf
116 } else {
117 f64::NAN // log(-Inf) = NaN
118 }
119}
120
121#[cfg(not(test))]
122#[cfg(not(any(target_os = "solaris", target_os = "illumos")))]
123#[inline]
124pub fn log_wrapper<F: Fn(f64) -> f64>(n: f64, log_fn: F) -> f64 {
125 log_fn(n)
126}
127
128#[cfg(not(target_os = "uefi"))]
129pub type RawOsError = i32;
130