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Diffstat (limited to 'ctr-std/src/ffi/c_str.rs')
| -rw-r--r-- | ctr-std/src/ffi/c_str.rs | 849 |
1 files changed, 849 insertions, 0 deletions
diff --git a/ctr-std/src/ffi/c_str.rs b/ctr-std/src/ffi/c_str.rs new file mode 100644 index 0000000..ad40660 --- /dev/null +++ b/ctr-std/src/ffi/c_str.rs @@ -0,0 +1,849 @@ +// Copyright 2012 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 ascii; +use borrow::{Cow, Borrow}; +use cmp::Ordering; +use error::Error; +use fmt::{self, Write}; +use io; +use libc::{self, c_char}; +use mem; +use memchr; +use ops; +use ptr; +use slice; +use str::{self, Utf8Error}; + +/// A type representing an owned C-compatible string +/// +/// This type serves the primary 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 and the final byte is 0. +/// +/// A `CString` is created from either a byte slice or a byte vector. After +/// being created, a `CString` predominately inherits all of its methods from +/// the `Deref` implementation to `[c_char]`. Note that the underlying array +/// is represented as an array of `c_char` as opposed to `u8`. A `u8` slice +/// can be obtained with the `as_bytes` method. Slices produced from a `CString` +/// do *not* contain the trailing nul terminator unless otherwise specified. +/// +/// # Examples +/// +/// ```no_run +/// # fn main() { +/// use std::ffi::CString; +/// use std::os::raw::c_char; +/// +/// extern { +/// fn my_printer(s: *const c_char); +/// } +/// +/// let c_to_print = CString::new("Hello, world!").unwrap(); +/// unsafe { +/// my_printer(c_to_print.as_ptr()); +/// } +/// # } +/// ``` +/// +/// # Safety +/// +/// `CString` is intended for working with traditional C-style strings +/// (a sequence of non-null bytes terminated by a single null byte); the +/// primary use case for these kinds of strings is interoperating with C-like +/// code. Often you will need to transfer ownership to/from that external +/// code. It is strongly recommended that you thoroughly read through the +/// documentation of `CString` before use, as improper ownership management +/// of `CString` instances can lead to invalid memory accesses, memory leaks, +/// and other memory errors. + +#[derive(PartialEq, PartialOrd, Eq, Ord, Hash, Clone)] +#[stable(feature = "rust1", since = "1.0.0")] +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 dynamically sized type is only safely constructed via a borrowed +/// version of an instance of `CString`. This type can be constructed from a raw +/// C string as well and represents a C string borrowed from another location. +/// +/// 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. +/// +/// # Examples +/// +/// Inspecting a foreign C string +/// +/// ```no_run +/// use std::ffi::CStr; +/// use std::os::raw::c_char; +/// +/// extern { fn my_string() -> *const c_char; } +/// +/// unsafe { +/// let slice = CStr::from_ptr(my_string()); +/// println!("string length: {}", slice.to_bytes().len()); +/// } +/// ``` +/// +/// Passing a Rust-originating C string +/// +/// ```no_run +/// use std::ffi::{CString, CStr}; +/// use std::os::raw::c_char; +/// +/// fn work(data: &CStr) { +/// extern { fn work_with(data: *const c_char); } +/// +/// unsafe { work_with(data.as_ptr()) } +/// } +/// +/// let s = CString::new("data data data data").unwrap(); +/// work(&s); +/// ``` +/// +/// Converting a foreign C string into a Rust `String` +/// +/// ```no_run +/// use std::ffi::CStr; +/// use std::os::raw::c_char; +/// +/// extern { fn my_string() -> *const c_char; } +/// +/// fn my_string_safe() -> String { +/// unsafe { +/// CStr::from_ptr(my_string()).to_string_lossy().into_owned() +/// } +/// } +/// +/// println!("string: {}", my_string_safe()); +/// ``` +#[derive(Hash)] +#[stable(feature = "rust1", since = "1.0.0")] +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 returned from `CString::new` to indicate that a nul byte was found +/// in the vector provided. +#[derive(Clone, PartialEq, Eq, Debug)] +#[stable(feature = "rust1", since = "1.0.0")] +pub struct NulError(usize, Vec<u8>); + +/// An error returned from `CStr::from_bytes_with_nul` to indicate that a nul +/// byte was found too early in the slice provided or one wasn't found at all. +#[derive(Clone, PartialEq, Eq, Debug)] +#[stable(feature = "cstr_from_bytes", since = "1.10.0")] +pub struct FromBytesWithNulError { _a: () } + +/// An error returned from `CString::into_string` to indicate that a UTF-8 error +/// was encountered during the conversion. +#[derive(Clone, PartialEq, Eq, Debug)] +#[stable(feature = "cstring_into", since = "1.7.0")] +pub struct IntoStringError { + inner: CString, + error: Utf8Error, +} + +impl CString { + /// Creates a new C-compatible string from a container of bytes. + /// + /// This method will consume the provided data and use the underlying bytes + /// to construct a new string, ensuring that there is a trailing 0 byte. + /// + /// # Examples + /// + /// ```no_run + /// use std::ffi::CString; + /// use std::os::raw::c_char; + /// + /// extern { fn puts(s: *const c_char); } + /// + /// let to_print = CString::new("Hello!").unwrap(); + /// unsafe { + /// puts(to_print.as_ptr()); + /// } + /// ``` + /// + /// # Errors + /// + /// This function will return an error if the bytes yielded contain an + /// internal 0 byte. The error returned will contain the bytes as well as + /// the position of the nul byte. + #[stable(feature = "rust1", since = "1.0.0")] + pub fn new<T: Into<Vec<u8>>>(t: T) -> Result<CString, NulError> { + Self::_new(t.into()) + } + + 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 from 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. + /// + /// # Examples + /// + /// ``` + /// use std::ffi::CString; + /// + /// let raw = b"foo".to_vec(); + /// unsafe { + /// let c_string = CString::from_vec_unchecked(raw); + /// } + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + 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. + /// + /// 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. + #[stable(feature = "cstr_memory", since = "1.4.0")] + 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(ptr, len as usize); + CString { inner: mem::transmute(slice) } + } + + /// Transfers ownership of the string to a C caller. + /// + /// The pointer 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. + #[stable(feature = "cstr_memory", since = "1.4.0")] + 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 Unicode data. + /// + /// On failure, ownership of the original `CString` is returned. + #[stable(feature = "cstring_into", since = "1.7.0")] + 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()) }, + }) + } + + /// Returns the underlying byte buffer. + /// + /// The returned buffer does **not** contain the trailing nul separator and + /// it is guaranteed to not have any interior nul bytes. + #[stable(feature = "cstring_into", since = "1.7.0")] + 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 byte. + #[stable(feature = "cstring_into", since = "1.7.0")] + 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 separator and + /// it is guaranteed to not have any interior nul bytes. + #[stable(feature = "rust1", since = "1.0.0")] + 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 byte. + #[stable(feature = "rust1", since = "1.0.0")] + pub fn as_bytes_with_nul(&self) -> &[u8] { + &self.inner + } + + // Bypass "move out of struct which implements `Drop` trait" restriction. + fn into_inner(self) -> Box<[u8]> { + unsafe { + let result = ptr::read(&self.inner); + mem::forget(self); + result + } + } +} + +// 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. +#[stable(feature = "cstring_drop", since = "1.13.0")] +impl Drop for CString { + #[inline] + fn drop(&mut self) { + unsafe { *self.inner.get_unchecked_mut(0) = 0; } + } +} + +#[stable(feature = "rust1", since = "1.0.0")] +impl ops::Deref for CString { + type Target = CStr; + + fn deref(&self) -> &CStr { + unsafe { mem::transmute(self.as_bytes_with_nul()) } + } +} + +#[stable(feature = "rust1", since = "1.0.0")] +impl fmt::Debug for CString { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + fmt::Debug::fmt(&**self, f) + } +} + +#[stable(feature = "cstring_into", since = "1.7.0")] +impl From<CString> for Vec<u8> { + fn from(s: CString) -> Vec<u8> { + s.into_bytes() + } +} + +#[stable(feature = "cstr_debug", since = "1.3.0")] +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, "\"") + } +} + +#[stable(feature = "cstr_default", since = "1.10.0")] +impl<'a> Default for &'a CStr { + fn default() -> &'a CStr { + static SLICE: &'static [c_char] = &[0]; + unsafe { CStr::from_ptr(SLICE.as_ptr()) } + } +} + +#[stable(feature = "cstr_default", since = "1.10.0")] +impl Default for CString { + /// Creates an empty `CString`. + fn default() -> CString { + let a: &CStr = Default::default(); + a.to_owned() + } +} + +#[stable(feature = "cstr_borrow", since = "1.3.0")] +impl Borrow<CStr> for CString { + fn borrow(&self) -> &CStr { self } +} + +impl NulError { + /// Returns the position of the nul byte in the slice that was provided to + /// `CString::new`. + /// + /// # Examples + /// + /// ``` + /// use std::ffi::CString; + /// + /// let nul_error = CString::new("foo\0bar").unwrap_err(); + /// assert_eq!(nul_error.nul_position(), 3); + /// + /// let nul_error = CString::new("foo bar\0").unwrap_err(); + /// assert_eq!(nul_error.nul_position(), 7); + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + 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. + /// + /// # Examples + /// + /// ``` + /// use std::ffi::CString; + /// + /// let nul_error = CString::new("foo\0bar").unwrap_err(); + /// assert_eq!(nul_error.into_vec(), b"foo\0bar"); + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn into_vec(self) -> Vec<u8> { self.1 } +} + +#[stable(feature = "rust1", since = "1.0.0")] +impl Error for NulError { + fn description(&self) -> &str { "nul byte found in data" } +} + +#[stable(feature = "rust1", since = "1.0.0")] +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) + } +} + +#[stable(feature = "rust1", since = "1.0.0")] +impl From<NulError> for io::Error { + fn from(_: NulError) -> io::Error { + io::Error::new(io::ErrorKind::InvalidInput, + "data provided contains a nul byte") + } +} + +impl IntoStringError { + /// Consumes this error, returning original `CString` which generated the + /// error. + #[stable(feature = "cstring_into", since = "1.7.0")] + pub fn into_cstring(self) -> CString { + self.inner + } + + /// Access the underlying UTF-8 error that was the cause of this error. + #[stable(feature = "cstring_into", since = "1.7.0")] + pub fn utf8_error(&self) -> Utf8Error { + self.error + } +} + +#[stable(feature = "cstring_into", since = "1.7.0")] +impl Error for IntoStringError { + fn description(&self) -> &str { + "C string contained non-utf8 bytes" + } + + fn cause(&self) -> Option<&Error> { + Some(&self.error) + } +} + +#[stable(feature = "cstring_into", since = "1.7.0")] +impl fmt::Display for IntoStringError { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + self.description().fmt(f) + } +} + +impl CStr { + /// Casts a raw C string to a safe C string wrapper. + /// + /// This function will cast the provided `ptr` to the `CStr` wrapper which + /// allows inspection and interoperation of non-owned C strings. 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. + /// + /// > **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. + /// + /// # Examples + /// + /// ```no_run + /// # fn main() { + /// use std::ffi::CStr; + /// use std::os::raw::c_char; + /// + /// extern { + /// fn my_string() -> *const c_char; + /// } + /// + /// unsafe { + /// let slice = CStr::from_ptr(my_string()); + /// println!("string returned: {}", slice.to_str().unwrap()); + /// } + /// # } + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub unsafe fn from_ptr<'a>(ptr: *const c_char) -> &'a CStr { + let len = libc::strlen(ptr); + mem::transmute(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 it is null terminated and does not contain any interior + /// nul bytes. + /// + /// # Examples + /// + /// ``` + /// use std::ffi::CStr; + /// + /// let cstr = CStr::from_bytes_with_nul(b"hello\0"); + /// assert!(cstr.is_ok()); + /// ``` + #[stable(feature = "cstr_from_bytes", since = "1.10.0")] + pub fn from_bytes_with_nul(bytes: &[u8]) + -> Result<&CStr, FromBytesWithNulError> { + if bytes.is_empty() || memchr::memchr(0, &bytes) != Some(bytes.len() - 1) { + Err(FromBytesWithNulError { _a: () }) + } else { + Ok(unsafe { Self::from_bytes_with_nul_unchecked(bytes) }) + } + } + + /// 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 null terminated + /// and not contain any interior nul bytes. + /// + /// # Examples + /// + /// ``` + /// use std::ffi::{CStr, CString}; + /// + /// unsafe { + /// let cstring = CString::new("hello").unwrap(); + /// let cstr = CStr::from_bytes_with_nul_unchecked(cstring.to_bytes_with_nul()); + /// assert_eq!(cstr, &*cstring); + /// } + /// ``` + #[stable(feature = "cstr_from_bytes", since = "1.10.0")] + pub unsafe fn from_bytes_with_nul_unchecked(bytes: &[u8]) -> &CStr { + mem::transmute(bytes) + } + + /// 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. + /// + /// **WARNING** + /// + /// It is your responsibility to make sure that the underlying memory is not + /// freed too early. For example, the following code will cause undefined + /// behaviour when `ptr` is used inside the `unsafe` block: + /// + /// ```no_run + /// use std::ffi::{CString}; + /// + /// let ptr = CString::new("Hello").unwrap().as_ptr(); + /// unsafe { + /// // `ptr` is dangling + /// *ptr; + /// } + /// ``` + /// + /// This happens because the pointer returned by `as_ptr` does not carry any + /// lifetime information and the string is deallocated immediately after + /// the `CString::new("Hello").unwrap().as_ptr()` expression is evaluated. + /// To fix the problem, bind the string to a local variable: + /// + /// ```no_run + /// use std::ffi::{CString}; + /// + /// let hello = CString::new("Hello").unwrap(); + /// let ptr = hello.as_ptr(); + /// unsafe { + /// // `ptr` is valid because `hello` is in scope + /// *ptr; + /// } + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn as_ptr(&self) -> *const c_char { + self.inner.as_ptr() + } + + /// Converts this C string to a byte slice. + /// + /// This function will calculate the length of this string (which normally + /// requires a linear amount of work to be done) and then return the + /// resulting slice of `u8` elements. + /// + /// The returned slice will **not** contain the trailing nul that this C + /// string has. + /// + /// > **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. + #[stable(feature = "rust1", since = "1.0.0")] + 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 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. + #[stable(feature = "rust1", since = "1.0.0")] + pub fn to_bytes_with_nul(&self) -> &[u8] { + unsafe { mem::transmute(&self.inner) } + } + + /// Yields a `&str` slice if the `CStr` contains valid UTF-8. + /// + /// This function will calculate the length of this string and check for + /// UTF-8 validity, and then return the `&str` if it's valid. + /// + /// > **Note**: This method is currently implemented to check for validity + /// > after a 0-cost cast, but it is planned to alter its definition in the + /// > future to perform the length calculation in addition to the UTF-8 + /// > check whenever this method is called. + #[stable(feature = "cstr_to_str", since = "1.4.0")] + pub fn to_str(&self) -> Result<&str, str::Utf8Error> { + // NB: 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>`. + /// + /// This function will calculate the length of this string (which normally + /// requires a linear amount of work to be done) and then return the + /// resulting slice as a `Cow<str>`, replacing any invalid UTF-8 sequences + /// with `U+FFFD REPLACEMENT CHARACTER`. + /// + /// > **Note**: This method is currently implemented to check for validity + /// > after a 0-cost cast, but it is planned to alter its definition in the + /// > future to perform the length calculation in addition to the UTF-8 + /// > check whenever this method is called. + #[stable(feature = "cstr_to_str", since = "1.4.0")] + pub fn to_string_lossy(&self) -> Cow<str> { + String::from_utf8_lossy(self.to_bytes()) + } +} + +#[stable(feature = "rust1", since = "1.0.0")] +impl PartialEq for CStr { + fn eq(&self, other: &CStr) -> bool { + self.to_bytes().eq(other.to_bytes()) + } +} +#[stable(feature = "rust1", since = "1.0.0")] +impl Eq for CStr {} +#[stable(feature = "rust1", since = "1.0.0")] +impl PartialOrd for CStr { + fn partial_cmp(&self, other: &CStr) -> Option<Ordering> { + self.to_bytes().partial_cmp(&other.to_bytes()) + } +} +#[stable(feature = "rust1", since = "1.0.0")] +impl Ord for CStr { + fn cmp(&self, other: &CStr) -> Ordering { + self.to_bytes().cmp(&other.to_bytes()) + } +} + +#[stable(feature = "cstr_borrow", since = "1.3.0")] +impl ToOwned for CStr { + type Owned = CString; + + fn to_owned(&self) -> CString { + unsafe { CString::from_vec_unchecked(self.to_bytes().to_vec()) } + } +} + +#[stable(feature = "cstring_asref", since = "1.7.0")] +impl<'a> From<&'a CStr> for CString { + fn from(s: &'a CStr) -> CString { + s.to_owned() + } +} + +#[stable(feature = "cstring_asref", since = "1.7.0")] +impl ops::Index<ops::RangeFull> for CString { + type Output = CStr; + + #[inline] + fn index(&self, _index: ops::RangeFull) -> &CStr { + self + } +} + +#[stable(feature = "cstring_asref", since = "1.7.0")] +impl AsRef<CStr> for CStr { + fn as_ref(&self) -> &CStr { + self + } +} + +#[stable(feature = "cstring_asref", since = "1.7.0")] +impl AsRef<CStr> for CString { + fn as_ref(&self) -> &CStr { + self + } +} + +#[cfg(test)] +mod tests { + use super::*; + use os::raw::c_char; + use borrow::Cow::{Borrowed, Owned}; + use hash::{Hash, Hasher}; + use collections::hash_map::DefaultHasher; + + #[test] + fn c_to_rust() { + let data = b"123\0"; + let ptr = data.as_ptr() as *const c_char; + unsafe { + assert_eq!(CStr::from_ptr(ptr).to_bytes(), b"123"); + assert_eq!(CStr::from_ptr(ptr).to_bytes_with_nul(), b"123\0"); + } + } + + #[test] + fn simple() { + let s = CString::new("1234").unwrap(); + assert_eq!(s.as_bytes(), b"1234"); + assert_eq!(s.as_bytes_with_nul(), b"1234\0"); + } + + #[test] + fn build_with_zero1() { + assert!(CString::new(&b"\0"[..]).is_err()); + } + #[test] + fn build_with_zero2() { + assert!(CString::new(vec![0]).is_err()); + } + + #[test] + fn build_with_zero3() { + unsafe { + let s = CString::from_vec_unchecked(vec![0]); + assert_eq!(s.as_bytes(), b"\0"); + } + } + + #[test] + fn formatted() { + let s = CString::new(&b"abc\x01\x02\n\xE2\x80\xA6\xFF"[..]).unwrap(); + assert_eq!(format!("{:?}", s), r#""abc\x01\x02\n\xe2\x80\xa6\xff""#); + } + + #[test] + fn borrowed() { + unsafe { + let s = CStr::from_ptr(b"12\0".as_ptr() as *const _); + assert_eq!(s.to_bytes(), b"12"); + assert_eq!(s.to_bytes_with_nul(), b"12\0"); + } + } + + #[test] + fn to_str() { + let data = b"123\xE2\x80\xA6\0"; + let ptr = data.as_ptr() as *const c_char; + unsafe { + assert_eq!(CStr::from_ptr(ptr).to_str(), Ok("123…")); + assert_eq!(CStr::from_ptr(ptr).to_string_lossy(), Borrowed("123…")); + } + let data = b"123\xE2\0"; + let ptr = data.as_ptr() as *const c_char; + unsafe { + assert!(CStr::from_ptr(ptr).to_str().is_err()); + assert_eq!(CStr::from_ptr(ptr).to_string_lossy(), Owned::<str>(format!("123\u{FFFD}"))); + } + } + + #[test] + fn to_owned() { + let data = b"123\0"; + let ptr = data.as_ptr() as *const c_char; + + let owned = unsafe { CStr::from_ptr(ptr).to_owned() }; + assert_eq!(owned.as_bytes_with_nul(), data); + } + + #[test] + fn equal_hash() { + let data = b"123\xE2\xFA\xA6\0"; + let ptr = data.as_ptr() as *const c_char; + let cstr: &'static CStr = unsafe { CStr::from_ptr(ptr) }; + + let mut s = DefaultHasher::new(); + cstr.hash(&mut s); + let cstr_hash = s.finish(); + let mut s = DefaultHasher::new(); + CString::new(&data[..data.len() - 1]).unwrap().hash(&mut s); + let cstring_hash = s.finish(); + + assert_eq!(cstr_hash, cstring_hash); + } + + #[test] + fn from_bytes_with_nul() { + let data = b"123\0"; + let cstr = CStr::from_bytes_with_nul(data); + assert_eq!(cstr.map(CStr::to_bytes), Ok(&b"123"[..])); + let cstr = CStr::from_bytes_with_nul(data); + assert_eq!(cstr.map(CStr::to_bytes_with_nul), Ok(&b"123\0"[..])); + + unsafe { + let cstr = CStr::from_bytes_with_nul(data); + let cstr_unchecked = CStr::from_bytes_with_nul_unchecked(data); + assert_eq!(cstr, Ok(cstr_unchecked)); + } + } + + #[test] + fn from_bytes_with_nul_unterminated() { + let data = b"123"; + let cstr = CStr::from_bytes_with_nul(data); + assert!(cstr.is_err()); + } + + #[test] + fn from_bytes_with_nul_interior() { + let data = b"1\023\0"; + let cstr = CStr::from_bytes_with_nul(data); + assert!(cstr.is_err()); + } +} |