std: Redesign c_str and c_vec

This commit is an implementation of [RFC 494][rfc] which removes the entire
`std::c_vec` module and redesigns the `std::c_str` module as `std::ffi`.

[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0494-c_str-and-c_vec-stability.md

The interface of the new `CString` is outlined in the linked RFC, the primary
changes being:

* The `ToCStr` trait is gone, meaning the `with_c_str` and `to_c_str` methods
  are now gone. These two methods are replaced with a `CString::from_slice`
  method.
* The `CString` type is now just a wrapper around `Vec<u8>` with a static
  guarantee that there is a trailing nul byte with no internal nul bytes. This
  means that `CString` now implements `Deref<Target = [c_char]>`, which is where
  it gains most of its methods from. A few helper methods are added to acquire a
  slice of `u8` instead of `c_char`, as well as including a slice with the
  trailing nul byte if necessary.
* All usage of non-owned `CString` values is now done via two functions inside
  of `std::ffi`, called `c_str_to_bytes` and `c_str_to_bytes_with_nul`. These
  functions are now the one method used to convert a `*const c_char` to a Rust
  slice of `u8`.

Many more details, including newly deprecated methods, can be found linked in
the RFC. This is a:

[breaking-change]
Closes #20444

1 files changed, 2 insertions, 20 deletions

diff --git a/src/libstd/path/mod.rs b/src/libstd/path/mod.rs
index bf9ffbffe7d..2f014872402 100644
--- a/src/libstd/path/mod.rs
+++ b/src/libstd/path/mod.rs
@@ -62,7 +62,7 @@
 #![experimental]
 
 use core::kinds::Sized;
-use c_str::CString;
+use ffi::CString;
 use clone::Clone;
 use fmt;
 use iter::IteratorExt;
@@ -892,7 +892,7 @@ impl BytesContainer for Vec<u8> {
 impl BytesContainer for CString {
     #[inline]
     fn container_as_bytes<'a>(&'a self) -> &'a [u8] {
-        self.as_bytes_no_nul()
+        self.as_bytes()
     }
 }
 
@@ -913,21 +913,3 @@ impl<'a, Sized? T: BytesContainer> BytesContainer for &'a T {
 fn contains_nul<T: BytesContainer>(v: &T) -> bool {
     v.container_as_bytes().iter().any(|&x| x == 0)
 }
-
-#[cfg(test)]
-mod tests {
-    use prelude::v1::*;
-    use c_str::ToCStr;
-    use path::{WindowsPath, PosixPath};
-
-    #[test]
-    fn test_cstring() {
-        let input = "/foo/bar/baz";
-        let path: PosixPath = PosixPath::new(input.to_c_str());
-        assert_eq!(path.as_vec(), input.as_bytes());
-
-        let input = r"\foo\bar\baz";
-        let path: WindowsPath = WindowsPath::new(input.to_c_str());
-        assert_eq!(path.as_str().unwrap(), input);
-    }
-}