| //! Implementation of `errno` functionality for Unix systems. |
| //! |
| //! Adapted from `src/libstd/sys/unix/os.rs` in the Rust distribution. |
| |
| // Copyright 2015 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. |
| |
| use core::str; |
| #[cfg(target_os = "dragonfly")] |
| use errno_dragonfly::errno_location; |
| use libc::{self, c_char, c_int, size_t, strlen}; |
| |
| use crate::Errno; |
| |
| fn from_utf8_lossy(input: &[u8]) -> &str { |
| match str::from_utf8(input) { |
| Ok(valid) => valid, |
| Err(error) => unsafe { str::from_utf8_unchecked(&input[..error.valid_up_to()]) }, |
| } |
| } |
| |
| pub fn with_description<F, T>(err: Errno, callback: F) -> T |
| where |
| F: FnOnce(Result<&str, Errno>) -> T, |
| { |
| let mut buf = [0u8; 1024]; |
| let c_str = unsafe { |
| if strerror_r(err.0, buf.as_mut_ptr() as *mut _, buf.len() as size_t) < 0 { |
| let fm_err = errno(); |
| if fm_err != Errno(libc::ERANGE) { |
| return callback(Err(fm_err)); |
| } |
| } |
| let c_str_len = strlen(buf.as_ptr() as *const _); |
| &buf[..c_str_len] |
| }; |
| callback(Ok(from_utf8_lossy(c_str))) |
| } |
| |
| pub const STRERROR_NAME: &str = "strerror_r"; |
| |
| pub fn errno() -> Errno { |
| unsafe { Errno(*errno_location()) } |
| } |
| |
| pub fn set_errno(Errno(errno): Errno) { |
| unsafe { |
| *errno_location() = errno; |
| } |
| } |
| |
| extern "C" { |
| #[cfg(not(target_os = "dragonfly"))] |
| #[cfg_attr( |
| any(target_os = "macos", target_os = "ios", target_os = "freebsd"), |
| link_name = "__error" |
| )] |
| #[cfg_attr( |
| any( |
| target_os = "openbsd", |
| target_os = "netbsd", |
| target_os = "bitrig", |
| target_os = "android" |
| ), |
| link_name = "__errno" |
| )] |
| #[cfg_attr( |
| any(target_os = "solaris", target_os = "illumos"), |
| link_name = "___errno" |
| )] |
| #[cfg_attr(target_os = "haiku", link_name = "_errnop")] |
| #[cfg_attr(target_os = "linux", link_name = "__errno_location")] |
| #[cfg_attr(target_os = "aix", link_name = "_Errno")] |
| fn errno_location() -> *mut c_int; |
| |
| #[cfg_attr(target_os = "linux", link_name = "__xpg_strerror_r")] |
| fn strerror_r(errnum: c_int, buf: *mut c_char, buflen: size_t) -> c_int; |
| } |