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-rw-r--r--getrandom/src/util_libc.rs143
1 files changed, 0 insertions, 143 deletions
diff --git a/getrandom/src/util_libc.rs b/getrandom/src/util_libc.rs
deleted file mode 100644
index 5a05170..0000000
--- a/getrandom/src/util_libc.rs
+++ /dev/null
@@ -1,143 +0,0 @@
-// Copyright 2019 Developers of the Rand project.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-use crate::error::ERRNO_NOT_POSITIVE;
-use crate::util::LazyUsize;
-use crate::Error;
-use core::num::NonZeroU32;
-use core::ptr::NonNull;
-
-cfg_if! {
- if #[cfg(any(target_os = "netbsd", target_os = "openbsd", target_os = "android"))] {
- use libc::__errno as errno_location;
- } else if #[cfg(any(target_os = "linux", target_os = "emscripten", target_os = "redox"))] {
- use libc::__errno_location as errno_location;
- } else if #[cfg(any(target_os = "solaris", target_os = "illumos"))] {
- use libc::___errno as errno_location;
- } else if #[cfg(any(target_os = "macos", target_os = "freebsd", target_os = "dragonfly"))] {
- use libc::__error as errno_location;
- } else if #[cfg(target_os = "haiku")] {
- use libc::_errnop as errno_location;
- }
-}
-
-pub fn last_os_error() -> Error {
- #[cfg(not(target_os = "vxworks"))]
- let errno = unsafe { *errno_location() };
- #[cfg(target_os = "vxworks")]
- let errno = unsafe { libc::errnoGet() };
- if errno > 0 {
- Error::from(NonZeroU32::new(errno as u32).unwrap())
- } else {
- ERRNO_NOT_POSITIVE
- }
-}
-
-// Fill a buffer by repeatedly invoking a system call. The `sys_fill` function:
-// - should return -1 and set errno on failure
-// - should return the number of bytes written on success
-pub fn sys_fill_exact(
- mut buf: &mut [u8],
- sys_fill: impl Fn(&mut [u8]) -> libc::ssize_t,
-) -> Result<(), Error> {
- while !buf.is_empty() {
- let res = sys_fill(buf);
- if res < 0 {
- let err = last_os_error();
- // We should try again if the call was interrupted.
- if err.raw_os_error() != Some(libc::EINTR) {
- return Err(err);
- }
- } else {
- // We don't check for EOF (ret = 0) as the data we are reading
- // should be an infinite stream of random bytes.
- buf = &mut buf[(res as usize)..];
- }
- }
- Ok(())
-}
-
-// A "weak" binding to a C function that may or may not be present at runtime.
-// Used for supporting newer OS features while still building on older systems.
-// F must be a function pointer of type `unsafe extern "C" fn`. Based off of the
-// weak! macro in libstd.
-pub struct Weak {
- name: &'static str,
- addr: LazyUsize,
-}
-
-impl Weak {
- // Construct a binding to a C function with a given name. This function is
- // unsafe because `name` _must_ be null terminated.
- pub const unsafe fn new(name: &'static str) -> Self {
- Self {
- name,
- addr: LazyUsize::new(),
- }
- }
-
- // Return a function pointer if present at runtime. Otherwise, return null.
- pub fn ptr(&self) -> Option<NonNull<libc::c_void>> {
- let addr = self.addr.unsync_init(|| unsafe {
- libc::dlsym(libc::RTLD_DEFAULT, self.name.as_ptr() as *const _) as usize
- });
- NonNull::new(addr as *mut _)
- }
-}
-
-pub struct LazyFd(LazyUsize);
-
-impl LazyFd {
- pub const fn new() -> Self {
- Self(LazyUsize::new())
- }
-
- // If init() returns Some(x), x should be nonnegative.
- pub fn init(&self, init: impl FnOnce() -> Option<libc::c_int>) -> Option<libc::c_int> {
- let fd = self.0.sync_init(
- || match init() {
- // OK as val >= 0 and val <= c_int::MAX < usize::MAX
- Some(val) => val as usize,
- None => LazyUsize::UNINIT,
- },
- || unsafe {
- // We are usually waiting on an open(2) syscall to complete,
- // which typically takes < 10us if the file is a device.
- // However, we might end up waiting much longer if the entropy
- // pool isn't initialized, but even in that case, this loop will
- // consume a negligible amount of CPU on most platforms.
- libc::usleep(10);
- },
- );
- match fd {
- LazyUsize::UNINIT => None,
- val => Some(val as libc::c_int),
- }
- }
-}
-
-cfg_if! {
- if #[cfg(any(target_os = "linux", target_os = "emscripten"))] {
- use libc::open64 as open;
- } else {
- use libc::open;
- }
-}
-
-// SAFETY: path must be null terminated, FD must be manually closed.
-pub unsafe fn open_readonly(path: &str) -> Option<libc::c_int> {
- debug_assert!(path.as_bytes().last() == Some(&0));
- let fd = open(path.as_ptr() as *mut _, libc::O_RDONLY | libc::O_CLOEXEC);
- if fd < 0 {
- return None;
- }
- // O_CLOEXEC works on all Unix targets except for older Linux kernels (pre
- // 2.6.23), so we also use an ioctl to make sure FD_CLOEXEC is set.
- #[cfg(target_os = "linux")]
- libc::ioctl(fd, libc::FIOCLEX);
- Some(fd)
-}