Rollup merge of #85275 - CDirkx:memchr, r=m-ou-se

Move `std::memchr` to `sys_common`

`std::memchr` is a thin abstraction over the different `memchr` implementations in `sys`, along with documentation and tests. The module is only used internally by `std`, nothing is exported externally. Code like this is exactly what the `sys_common` module is for, so this PR moves it there.

library/std/src/ffi/c_str.rs

@@ -10,7 +10,6 @@ use crate::error::Error;
 use crate::fmt::{self, Write};
 use crate::io;
 use crate::mem;
-use crate::memchr;
 use crate::num::NonZeroU8;
 use crate::ops;
 use crate::os::raw::c_char;
@@ -20,6 +19,7 @@ use crate::slice;
 use crate::str::{self, Utf8Error};
 use crate::sync::Arc;
 use crate::sys;
+use crate::sys_common::memchr;
 
 /// A type representing an owned, C-compatible, nul-terminated string with no nul bytes in the
 /// middle.

library/std/src/io/buffered/linewritershim.rs

@@ -1,5 +1,5 @@
 use crate::io::{self, BufWriter, IoSlice, Write};
-use crate::memchr;
+use crate::sys_common::memchr;
 
 /// Private helper struct for implementing the line-buffered writing logic.
 /// This shim temporarily wraps a BufWriter, and uses its internals to

library/std/src/io/mod.rs

@@ -253,12 +253,12 @@ mod tests;
 
 use crate::cmp;
 use crate::fmt;
-use crate::memchr;
 use crate::ops::{Deref, DerefMut};
 use crate::ptr;
 use crate::slice;
 use crate::str;
 use crate::sys;
+use crate::sys_common::memchr;
 
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use self::buffered::IntoInnerError;

library/std/src/lib.rs

@@ -530,7 +530,6 @@ mod sys;
 pub mod alloc;
 
 // Private support modules
-mod memchr;
 mod panicking;
 
 // The runtime entry point and a few unstable public functions used by the

library/std/src/sys/hermit/os.rs

@@ -4,11 +4,11 @@ use crate::ffi::{CStr, OsStr, OsString};
 use crate::fmt;
 use crate::io;
 use crate::marker::PhantomData;
-use crate::memchr;
 use crate::path::{self, PathBuf};
 use crate::str;
 use crate::sync::Mutex;
 use crate::sys::hermit::abi;
+use crate::sys::memchr;
 use crate::sys::unsupported;
 use crate::sys_common::os_str_bytes::*;
 use crate::vec;

library/std/src/sys/unix/os.rs

@@ -13,13 +13,13 @@ use crate::fmt;
 use crate::io;
 use crate::iter;
 use crate::mem;
-use crate::memchr;
 use crate::path::{self, PathBuf};
 use crate::ptr;
 use crate::slice;
 use crate::str;
 use crate::sys::cvt;
 use crate::sys::fd;
+use crate::sys::memchr;
 use crate::sys::rwlock::{RWLockReadGuard, StaticRWLock};
 use crate::sys_common::mutex::{StaticMutex, StaticMutexGuard};
 use crate::vec;

library/std/src/sys_common/memchr.rs

@@ -1,6 +1,8 @@
 // Original implementation taken from rust-memchr.
 // Copyright 2015 Andrew Gallant, bluss and Nicolas Koch
 
+use crate::sys::memchr as sys;
+
 #[cfg(test)]
 mod tests;
 
@@ -25,7 +27,7 @@ mod tests;
 /// ```
 #[inline]
 pub fn memchr(needle: u8, haystack: &[u8]) -> Option<usize> {
-    crate::sys::memchr::memchr(needle, haystack)
+    sys::memchr(needle, haystack)
 }
 
 /// A safe interface to `memrchr`.
@@ -45,5 +47,5 @@ pub fn memchr(needle: u8, haystack: &[u8]) -> Option<usize> {
 /// ```
 #[inline]
 pub fn memrchr(needle: u8, haystack: &[u8]) -> Option<usize> {
-    crate::sys::memchr::memrchr(needle, haystack)
+    sys::memrchr(needle, haystack)
 }

library/std/src/sys_common/mod.rs

@@ -25,6 +25,7 @@ pub mod bytestring;
 pub mod condvar;
 pub mod fs;
 pub mod io;
+pub mod memchr;
 pub mod mutex;
 // `doc` is required because `sys/mod.rs` imports `unix/ext/mod.rs` on Windows
 // when generating documentation.