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// Licensed to the Apache Software Foundation (ASF) under one // or more contributor license agreements. See the NOTICE file // distributed with this work for additional information // regarding copyright ownership. The ASF licenses this file // to you under the Apache License, Version 2.0 (the // "License"); you may not use this file except in compliance // with the License. You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, // software distributed under the License is distributed on an // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY // KIND, either express or implied. See the License for the // specific language governing permissions and limitations // under the License.. /// A type representing an owned, C-compatible, nul-terminated string with no nul bytes in the /// middle. /// /// This type serves the purpose of being able to safely generate a /// C-compatible string from a Rust byte slice or vector. An instance of this /// type is a static guarantee that the underlying bytes contain no interior 0 /// bytes ("nul characters") and that the final byte is 0 ("nul terminator"). /// use sgx_types::c_char; use crate::libc; use crate::memchr; use crate::ascii; use core::ops; use core::cmp::Ordering; use core::mem; use core::ptr; use core::fmt::{self, Write}; use core::num::NonZeroU8; use alloc::boxed::Box; use alloc::borrow::{Cow, Borrow, ToOwned}; use alloc::vec::Vec; use alloc::string::String; use alloc::slice; use alloc::rc::Rc; use alloc::sync::Arc; use alloc::str::{self, Utf8Error}; /// A type representing an owned C-compatible string /// #[derive(PartialEq, PartialOrd, Eq, Ord, Hash, Clone)] pub struct CString { // Invariant 1: the slice ends with a zero byte and has a length of at least one. // Invariant 2: the slice contains only one zero byte. // Improper usage of unsafe function can break Invariant 2, but not Invariant 1. inner: Box<[u8]>, } /// Representation of a borrowed C string. /// /// This type represents a borrowed reference to a nul-terminated /// array of bytes. It can be constructed safely from a `&[`[`u8`]`]` /// slice, or unsafely from a raw `*const c_char`. It can then be /// converted to a Rust [`&str`] by performing UTF-8 validation, or /// into an owned [`CString`]. /// /// `&CStr` is to [`CString`] as [`&str`] is to [`String`]: the former /// in each pair are borrowed references; the latter are owned /// strings. /// /// Note that this structure is **not** `repr(C)` and is not recommended to be /// placed in the signatures of FFI functions. Instead, safe wrappers of FFI /// functions may leverage the unsafe [`from_ptr`] constructor to provide a safe /// interface to other consumers. /// #[derive(Hash)] pub struct CStr { // FIXME: this should not be represented with a DST slice but rather with // just a raw `c_char` along with some form of marker to make // this an unsized type. Essentially `sizeof(&CStr)` should be the // same as `sizeof(&c_char)` but `CStr` should be an unsized type. inner: [c_char], } /// An error indicating that an interior nul byte was found. /// /// While Rust strings may contain nul bytes in the middle, C strings /// can't, as that byte would effectively truncate the string. /// /// This error is created by the [`new`][`CString::new`] method on /// [`CString`]. See its documentation for more. /// /// [`CString`]: struct.CString.html /// [`CString::new`]: struct.CString.html#method.new /// #[derive(Clone, PartialEq, Eq, Debug)] pub struct NulError(usize, Vec<u8>); impl fmt::Display for NulError { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!(f, "nul byte found in provided data at position: {}", self.0) } } /// An error indicating that a nul byte was not in the expected position. /// /// The slice used to create a [`CStr`] must have one and only one nul /// byte at the end of the slice. /// /// This error is created by the /// [`from_bytes_with_nul`][`CStr::from_bytes_with_nul`] method on /// [`CStr`]. See its documentation for more. /// /// [`CStr`]: struct.CStr.html /// [`CStr::from_bytes_with_nul`]: struct.CStr.html#method.from_bytes_with_nul /// #[derive(Clone, PartialEq, Eq, Debug)] pub struct FromBytesWithNulError { kind: FromBytesWithNulErrorKind, } #[derive(Clone, PartialEq, Eq, Debug)] enum FromBytesWithNulErrorKind { InteriorNul(usize), NotNulTerminated, } impl FromBytesWithNulError { fn interior_nul(pos: usize) -> FromBytesWithNulError { FromBytesWithNulError { kind: FromBytesWithNulErrorKind::InteriorNul(pos) } } fn not_nul_terminated() -> FromBytesWithNulError { FromBytesWithNulError { kind: FromBytesWithNulErrorKind::NotNulTerminated } } pub fn __description(&self) -> &str { match self.kind { FromBytesWithNulErrorKind::InteriorNul(..) => { "data provided contains an interior nul byte" } FromBytesWithNulErrorKind::NotNulTerminated => "data provided is not nul terminated", } } } impl fmt::Display for FromBytesWithNulError { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { f.write_str(self.__description())?; if let FromBytesWithNulErrorKind::InteriorNul(pos) = self.kind { write!(f, " at byte pos {}", pos)?; } Ok(()) } } /// An error indicating invalid UTF-8 when converting a [`CString`] into a [`String`]. /// /// `CString` is just a wrapper over a buffer of bytes with a nul /// terminator; [`into_string`][`CString::into_string`] performs UTF-8 /// validation on those bytes and may return this error. /// /// This `struct` is created by the /// [`into_string`][`CString::into_string`] method on [`CString`]. See /// its documentation for more. /// /// [`String`]: ../string/struct.String.html /// [`CString`]: struct.CString.html /// [`CString::into_string`]: struct.CString.html#method.into_string #[derive(Clone, PartialEq, Eq, Debug)] pub struct IntoStringError { inner: CString, error: Utf8Error, } impl IntoStringError { pub fn __description(&self) -> &str { "C string contained non-utf8 bytes" } pub fn __source(&self) -> &Utf8Error { &self.error } } impl fmt::Display for IntoStringError { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { self.__description().fmt(f) } } impl CString { /// Creates a new C-compatible string from a container of bytes. /// /// This function will consume the provided data and use the /// underlying bytes to construct a new string, ensuring that /// there is a trailing 0 byte. This trailing 0 byte will be /// appended by this function; the provided data should *not* /// contain any 0 bytes in it. /// pub fn new<T: Into<Vec<u8>>>(t: T) -> Result<CString, NulError> { trait SpecIntoVec { fn into_vec(self) -> Vec<u8>; } impl<T: Into<Vec<u8>>> SpecIntoVec for T { default fn into_vec(self) -> Vec<u8> { self.into() } } // Specialization for avoiding reallocation. impl SpecIntoVec for &'_ [u8] { fn into_vec(self) -> Vec<u8> { let mut v = Vec::with_capacity(self.len() + 1); v.extend(self); v } } impl SpecIntoVec for &'_ str { fn into_vec(self) -> Vec<u8> { let mut v = Vec::with_capacity(self.len() + 1); v.extend(self.as_bytes()); v } } Self::_new(SpecIntoVec::into_vec(t)) } fn _new(bytes: Vec<u8>) -> Result<CString, NulError> { match memchr::memchr(0, &bytes) { Some(i) => Err(NulError(i, bytes)), None => Ok(unsafe { CString::from_vec_unchecked(bytes) }), } } /// Creates a C-compatible string by consuming a byte vector, /// without checking for interior 0 bytes. /// /// This method is equivalent to [`new`] except that no runtime assertion /// is made that `v` contains no 0 bytes, and it requires an actual /// byte vector, not anything that can be converted to one with Into. /// /// [`new`]: #method.new /// pub unsafe fn from_vec_unchecked(mut v: Vec<u8>) -> CString { v.reserve_exact(1); v.push(0); CString { inner: v.into_boxed_slice() } } /// Retakes ownership of a `CString` that was transferred to C via [`into_raw`]. /// /// Additionally, the length of the string will be recalculated from the pointer. /// /// # Safety /// /// This should only ever be called with a pointer that was earlier /// obtained by calling [`into_raw`] on a `CString`. Other usage (e.g., trying to take /// ownership of a string that was allocated by foreign code) is likely to lead /// to undefined behavior or allocator corruption. /// /// > **Note:** If you need to borrow a string that was allocated by /// > foreign code, use [`CStr`]. If you need to take ownership of /// > a string that was allocated by foreign code, you will need to /// > make your own provisions for freeing it appropriately, likely /// > with the foreign code's API to do that. /// /// [`into_raw`]: #method.into_raw /// [`CStr`]: struct.CStr.html /// pub unsafe fn from_raw(ptr: *mut c_char) -> CString { let len = libc::strlen(ptr) + 1; // Including the NUL byte let slice = slice::from_raw_parts_mut(ptr, len as usize); CString { inner: Box::from_raw(slice as *mut [c_char] as *mut [u8]) } } /// Consumes the `CString` and transfers ownership of the string to a C caller. /// /// The pointer which this function returns must be returned to Rust and reconstituted using /// [`from_raw`] to be properly deallocated. Specifically, one /// should *not* use the standard C `free()` function to deallocate /// this string. /// /// Failure to call [`from_raw`] will lead to a memory leak. /// /// [`from_raw`]: #method.from_raw /// #[inline] pub fn into_raw(self) -> *mut c_char { Box::into_raw(self.into_inner()) as *mut c_char } /// Converts the `CString` into a [`String`] if it contains valid UTF-8 data. /// /// On failure, ownership of the original `CString` is returned. /// /// [`String`]: ../string/struct.String.html /// pub fn into_string(self) -> Result<String, IntoStringError> { String::from_utf8(self.into_bytes()).map_err(|e| IntoStringError { error: e.utf8_error(), inner: unsafe { CString::from_vec_unchecked(e.into_bytes()) }, }) } /// Consumes the `CString` and returns the underlying byte buffer. /// /// The returned buffer does **not** contain the trailing nul /// terminator, and it is guaranteed to not have any interior nul /// bytes. /// pub fn into_bytes(self) -> Vec<u8> { let mut vec = self.into_inner().into_vec(); let _nul = vec.pop(); debug_assert_eq!(_nul, Some(0u8)); vec } /// Equivalent to the [`into_bytes`] function except that the returned vector /// includes the trailing nul terminator. /// /// [`into_bytes`]: #method.into_bytes /// pub fn into_bytes_with_nul(self) -> Vec<u8> { self.into_inner().into_vec() } /// Returns the contents of this `CString` as a slice of bytes. /// /// The returned slice does **not** contain the trailing nul /// terminator, and it is guaranteed to not have any interior nul /// bytes. If you need the nul terminator, use /// [`as_bytes_with_nul`] instead. /// /// [`as_bytes_with_nul`]: #method.as_bytes_with_nul /// #[inline] pub fn as_bytes(&self) -> &[u8] { &self.inner[..self.inner.len() - 1] } /// Equivalent to the [`as_bytes`] function except that the returned slice /// includes the trailing nul terminator. #[inline] pub fn as_bytes_with_nul(&self) -> &[u8] { &self.inner } /// Extracts a [`CStr`] slice containing the entire string. #[inline] pub fn as_c_str(&self) -> &CStr { &*self } /// Converts this `CString` into a boxed [`CStr`]. /// /// [`CStr`]: struct.CStr.html /// pub fn into_boxed_c_str(self) -> Box<CStr> { unsafe { Box::from_raw(Box::into_raw(self.into_inner()) as *mut CStr) } } /// Bypass "move out of struct which implements [`Drop`] trait" restriction. /// /// [`Drop`]: ../ops/trait.Drop.html fn into_inner(self) -> Box<[u8]> { // Rationale: `mem::forget(self)` invalidates the previous call to `ptr::read(&self.inner)` // so we use `ManuallyDrop` to ensure `self` is not dropped. // Then we can return the box directly without invalidating it. // See https://github.com/rust-lang/rust/issues/62553. let this = mem::ManuallyDrop::new(self); unsafe { ptr::read(&this.inner) } } } // Turns this `CString` into an empty string to prevent // memory-unsafe code from working by accident. Inline // to prevent LLVM from optimizing it away in debug builds. impl Drop for CString { #[inline] fn drop(&mut self) { unsafe { *self.inner.get_unchecked_mut(0) = 0; } } } impl ops::Deref for CString { type Target = CStr; #[inline] fn deref(&self) -> &CStr { unsafe { CStr::from_bytes_with_nul_unchecked(self.as_bytes_with_nul()) } } } impl fmt::Debug for CString { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { fmt::Debug::fmt(&**self, f) } } impl From<CString> for Vec<u8> { /// Converts a [`CString`] into a [`Vec`]`<u8>`. /// /// The conversion consumes the [`CString`], and removes the terminating NUL byte. /// /// [`Vec`]: ../vec/struct.Vec.html /// [`CString`]: ../ffi/struct.CString.html #[inline] fn from(s: CString) -> Vec<u8> { s.into_bytes() } } impl fmt::Debug for CStr { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!(f, "\"")?; for byte in self.to_bytes().iter().flat_map(|&b| ascii::escape_default(b)) { f.write_char(byte as char)?; } write!(f, "\"") } } impl Default for &CStr { fn default() -> Self { const SLICE: &[c_char] = &[0]; unsafe { CStr::from_ptr(SLICE.as_ptr()) } } } impl Default for CString { /// Creates an empty `CString`. fn default() -> CString { let a: &CStr = Default::default(); a.to_owned() } } impl Borrow<CStr> for CString { #[inline] fn borrow(&self) -> &CStr { self } } impl<'a> From<Cow<'a, CStr>> for CString { #[inline] fn from(s: Cow<'a, CStr>) -> Self { s.into_owned() } } impl From<&CStr> for Box<CStr> { fn from(s: &CStr) -> Box<CStr> { let boxed: Box<[u8]> = Box::from(s.to_bytes_with_nul()); unsafe { Box::from_raw(Box::into_raw(boxed) as *mut CStr) } } } impl From<Box<CStr>> for CString { /// Converts a [`Box`]`<CStr>` into a [`CString`] without copying or allocating. /// /// [`Box`]: ../boxed/struct.Box.html /// [`CString`]: ../ffi/struct.CString.html #[inline] fn from(s: Box<CStr>) -> CString { s.into_c_string() } } impl From<Vec<NonZeroU8>> for CString { /// Converts a [`Vec`]`<`[`NonZeroU8`]`>` into a [`CString`] without /// copying nor checking for inner null bytes. /// /// [`CString`]: ../ffi/struct.CString.html /// [`NonZeroU8`]: ../num/struct.NonZeroU8.html /// [`Vec`]: ../vec/struct.Vec.html #[inline] fn from(v: Vec<NonZeroU8>) -> CString { unsafe { // Transmute `Vec<NonZeroU8>` to `Vec<u8>`. let v: Vec<u8> = { // Safety: // - transmuting between `NonZeroU8` and `u8` is sound; // - `alloc::Layout<NonZeroU8> == alloc::Layout<u8>`. let (ptr, len, cap): (*mut NonZeroU8, _, _) = Vec::into_raw_parts(v); Vec::from_raw_parts(ptr.cast::<u8>(), len, cap) }; // Safety: `v` cannot contain null bytes, given the type-level // invariant of `NonZeroU8`. CString::from_vec_unchecked(v) } } } impl Clone for Box<CStr> { #[inline] fn clone(&self) -> Self { (**self).into() } } impl From<CString> for Box<CStr> { /// Converts a [`CString`] into a [`Box`]`<CStr>` without copying or allocating. /// /// [`CString`]: ../ffi/struct.CString.html /// [`Box`]: ../boxed/struct.Box.html #[inline] fn from(s: CString) -> Box<CStr> { s.into_boxed_c_str() } } impl<'a> From<CString> for Cow<'a, CStr> { #[inline] fn from(s: CString) -> Cow<'a, CStr> { Cow::Owned(s) } } impl<'a> From<&'a CStr> for Cow<'a, CStr> { #[inline] fn from(s: &'a CStr) -> Cow<'a, CStr> { Cow::Borrowed(s) } } impl<'a> From<&'a CString> for Cow<'a, CStr> { #[inline] fn from(s: &'a CString) -> Cow<'a, CStr> { Cow::Borrowed(s.as_c_str()) } } impl From<CString> for Arc<CStr> { /// Converts a [`CString`] into a [`Arc`]`<CStr>` without copying or allocating. /// /// [`CString`]: ../ffi/struct.CString.html /// [`Arc`]: ../sync/struct.Arc.html #[inline] fn from(s: CString) -> Arc<CStr> { let arc: Arc<[u8]> = Arc::from(s.into_inner()); unsafe { Arc::from_raw(Arc::into_raw(arc) as *const CStr) } } } impl From<&CStr> for Arc<CStr> { #[inline] fn from(s: &CStr) -> Arc<CStr> { let arc: Arc<[u8]> = Arc::from(s.to_bytes_with_nul()); unsafe { Arc::from_raw(Arc::into_raw(arc) as *const CStr) } } } impl From<CString> for Rc<CStr> { /// Converts a [`CString`] into a [`Rc`]`<CStr>` without copying or allocating. /// /// [`CString`]: ../ffi/struct.CString.html /// [`Rc`]: ../rc/struct.Rc.html #[inline] fn from(s: CString) -> Rc<CStr> { let rc: Rc<[u8]> = Rc::from(s.into_inner()); unsafe { Rc::from_raw(Rc::into_raw(rc) as *const CStr) } } } impl From<&CStr> for Rc<CStr> { #[inline] fn from(s: &CStr) -> Rc<CStr> { let rc: Rc<[u8]> = Rc::from(s.to_bytes_with_nul()); unsafe { Rc::from_raw(Rc::into_raw(rc) as *const CStr) } } } impl Default for Box<CStr> { fn default() -> Box<CStr> { let boxed: Box<[u8]> = Box::from([0]); unsafe { Box::from_raw(Box::into_raw(boxed) as *mut CStr) } } } impl NulError { /// Returns the position of the nul byte in the slice that caused /// [`CString::new`] to fail. /// /// [`CString::new`]: struct.CString.html#method.new /// pub fn nul_position(&self) -> usize { self.0 } /// Consumes this error, returning the underlying vector of bytes which /// generated the error in the first place. /// pub fn into_vec(self) -> Vec<u8> { self.1 } } impl IntoStringError { /// Consumes this error, returning original [`CString`] which generated the /// error. /// /// [`CString`]: struct.CString.html pub fn into_cstring(self) -> CString { self.inner } /// Access the underlying UTF-8 error that was the cause of this error. pub fn utf8_error(&self) -> Utf8Error { self.error } } impl CStr { /// Wraps a raw C string with a safe C string wrapper. /// /// This function will wrap the provided `ptr` with a `CStr` wrapper, which /// allows inspection and interoperation of non-owned C strings. The total /// size of the raw C string must be smaller than `isize::MAX` **bytes** /// in memory due to calling the `slice::from_raw_parts` function. /// This method is unsafe for a number of reasons: /// /// * There is no guarantee to the validity of `ptr`. /// * The returned lifetime is not guaranteed to be the actual lifetime of /// `ptr`. /// * There is no guarantee that the memory pointed to by `ptr` contains a /// valid nul terminator byte at the end of the string. /// * It is not guaranteed that the memory pointed by `ptr` won't change /// before the `CStr` has been destroyed. /// /// > **Note**: This operation is intended to be a 0-cost cast but it is /// > currently implemented with an up-front calculation of the length of /// > the string. This is not guaranteed to always be the case. /// pub unsafe fn from_ptr<'a>(ptr: *const c_char) -> &'a CStr { let len = libc::strlen(ptr); let ptr = ptr as *const u8; CStr::from_bytes_with_nul_unchecked(slice::from_raw_parts(ptr, len as usize + 1)) } /// Creates a C string wrapper from a byte slice. /// /// This function will cast the provided `bytes` to a `CStr` /// wrapper after ensuring that the byte slice is nul-terminated /// and does not contain any interior nul bytes. /// pub fn from_bytes_with_nul(bytes: &[u8]) -> Result<&CStr, FromBytesWithNulError> { let nul_pos = memchr::memchr(0, bytes); if let Some(nul_pos) = nul_pos { if nul_pos + 1 != bytes.len() { return Err(FromBytesWithNulError::interior_nul(nul_pos)); } Ok(unsafe { CStr::from_bytes_with_nul_unchecked(bytes) }) } else { Err(FromBytesWithNulError::not_nul_terminated()) } } /// Unsafely creates a C string wrapper from a byte slice. /// /// This function will cast the provided `bytes` to a `CStr` wrapper without /// performing any sanity checks. The provided slice **must** be nul-terminated /// and not contain any interior nul bytes. /// #[inline] pub const unsafe fn from_bytes_with_nul_unchecked(bytes: &[u8]) -> &CStr { &*(bytes as *const [u8] as *const CStr) } /// Returns the inner pointer to this C string. /// /// The returned pointer will be valid for as long as `self` is, and points /// to a contiguous region of memory terminated with a 0 byte to represent /// the end of the string. /// #[inline] pub const fn as_ptr(&self) -> *const c_char { self.inner.as_ptr() } /// Converts this C string to a byte slice. /// /// The returned slice will **not** contain the trailing nul terminator that this C /// string has. /// /// > **Note**: This method is currently implemented as a constant-time /// > cast, but it is planned to alter its definition in the future to /// > perform the length calculation whenever this method is called. /// #[inline] pub fn to_bytes(&self) -> &[u8] { let bytes = self.to_bytes_with_nul(); &bytes[..bytes.len() - 1] } /// Converts this C string to a byte slice containing the trailing 0 byte. /// /// This function is the equivalent of [`to_bytes`] except that it will retain /// the trailing nul terminator instead of chopping it off. /// /// > **Note**: This method is currently implemented as a 0-cost cast, but /// > it is planned to alter its definition in the future to perform the /// > length calculation whenever this method is called. /// /// [`to_bytes`]: #method.to_bytes /// #[inline] pub fn to_bytes_with_nul(&self) -> &[u8] { unsafe { &*(&self.inner as *const [c_char] as *const [u8]) } } /// Yields a [`&str`] slice if the `CStr` contains valid UTF-8. /// /// If the contents of the `CStr` are valid UTF-8 data, this /// function will return the corresponding [`&str`] slice. Otherwise, /// it will return an error with details of where UTF-8 validation failed. /// /// [`&str`]: ../primitive.str.html /// pub fn to_str(&self) -> Result<&str, str::Utf8Error> { // N.B., when `CStr` is changed to perform the length check in `.to_bytes()` // instead of in `from_ptr()`, it may be worth considering if this should // be rewritten to do the UTF-8 check inline with the length calculation // instead of doing it afterwards. str::from_utf8(self.to_bytes()) } /// Converts a `CStr` into a [`Cow`]`<`[`str`]`>`. /// /// If the contents of the `CStr` are valid UTF-8 data, this /// function will return a [`Cow`]`::`[`Borrowed`]`(`[`&str`]`)` /// with the corresponding [`&str`] slice. Otherwise, it will /// replace any invalid UTF-8 sequences with /// [`U+FFFD REPLACEMENT CHARACTER`][U+FFFD] and return a /// [`Cow`]`::`[`Owned`]`(`[`String`]`)` with the result. /// /// [`Cow`]: ../borrow/enum.Cow.html /// [`Borrowed`]: ../borrow/enum.Cow.html#variant.Borrowed /// [`Owned`]: ../borrow/enum.Cow.html#variant.Owned /// [`str`]: ../primitive.str.html /// [`String`]: ../string/struct.String.html /// [U+FFFD]: ../char/constant.REPLACEMENT_CHARACTER.html /// pub fn to_string_lossy(&self) -> Cow<'_, str> { String::from_utf8_lossy(self.to_bytes()) } /// Converts a [`Box`]`<CStr>` into a [`CString`] without copying or allocating. /// /// [`Box`]: ../boxed/struct.Box.html /// [`CString`]: struct.CString.html /// pub fn into_c_string(self: Box<CStr>) -> CString { let raw = Box::into_raw(self) as *mut [u8]; CString { inner: unsafe { Box::from_raw(raw) } } } } impl PartialEq for CStr { fn eq(&self, other: &CStr) -> bool { self.to_bytes().eq(other.to_bytes()) } } impl Eq for CStr {} impl PartialOrd for CStr { fn partial_cmp(&self, other: &CStr) -> Option<Ordering> { self.to_bytes().partial_cmp(&other.to_bytes()) } } impl Ord for CStr { fn cmp(&self, other: &CStr) -> Ordering { self.to_bytes().cmp(&other.to_bytes()) } } impl ToOwned for CStr { type Owned = CString; fn to_owned(&self) -> CString { CString { inner: self.to_bytes_with_nul().into() } } fn clone_into(&self, target: &mut CString) { let mut b = Vec::from(mem::take(&mut target.inner)); self.to_bytes_with_nul().clone_into(&mut b); target.inner = b.into_boxed_slice(); } } impl From<&CStr> for CString { fn from(s: &CStr) -> CString { s.to_owned() } } impl ops::Index<ops::RangeFull> for CString { type Output = CStr; #[inline] fn index(&self, _index: ops::RangeFull) -> &CStr { self } } impl AsRef<CStr> for CStr { #[inline] fn as_ref(&self) -> &CStr { self } } impl AsRef<CStr> for CString { #[inline] fn as_ref(&self) -> &CStr { self } }