From 60274a95fef57a18113f7c48be68be31ece860eb Mon Sep 17 00:00:00 2001
From: Daniel Henry-Mantilla <daniel.henry.mantilla@gmail.com>
Date: Sun, 1 Sep 2019 17:23:20 +0200
Subject: Added From<Vec<NonZeroU8>> for CString

Updated tracking issue number

Added safeguards for transmute_vec potentially being factored out elsewhere

Clarified comment about avoiding mem::forget

Removed unneeded unstable guard

Added back a stability annotation for CI

Minor documentation improvements

Thanks to @Centril's code review

Co-Authored-By: Mazdak Farrokhzad <twingoow@gmail.com>

Improved layout checks, type annotations and removed unaccurate comment

Removed unnecessary check on array layout

Adapt the stability annotation to the new 1.41 milestone

Co-Authored-By: Mazdak Farrokhzad <twingoow@gmail.com>

Simplify the implementation.

Use `Vec::into_raw_parts` instead of a manual implementation of
`Vec::transmute`.

If `Vec::into_raw_parts` uses `NonNull` instead, then the code here
will need to be adjusted to take it into account (issue #65816)

Reduce the whitespace of safety comments
---
 src/libstd/ffi/c_str.rs | 27 +++++++++++++++++++++++++++
 src/libstd/lib.rs       |  1 +
 2 files changed, 28 insertions(+)

(limited to 'src/libstd')

diff --git a/src/libstd/ffi/c_str.rs b/src/libstd/ffi/c_str.rs
index d2ee65f0a74..217672ea292 100644
--- a/src/libstd/ffi/c_str.rs
+++ b/src/libstd/ffi/c_str.rs
@@ -6,6 +6,7 @@ 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;
 use crate::ptr;
@@ -741,6 +742,32 @@ impl From<Box<CStr>> for CString {
     }
 }
 
+#[stable(feature = "cstring_from_vec_of_nonzerou8", since = "1.43.0")]
+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)
+        }
+    }
+}
+
 #[stable(feature = "more_box_slice_clone", since = "1.29.0")]
 impl Clone for Box<CStr> {
     #[inline]
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index 9e9df5ab9b6..c05ebc7349d 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -310,6 +310,7 @@
 #![feature(unboxed_closures)]
 #![feature(untagged_unions)]
 #![feature(unwind_attributes)]
+#![feature(vec_into_raw_parts)]
 // NB: the above list is sorted to minimize merge conflicts.
 #![default_lib_allocator]
 
-- 
cgit 1.4.1-3-g733a5


From 8fb8bb4b3ff25570a7a9b105c1a569bb2307f25f Mon Sep 17 00:00:00 2001
From: Ingvar Stepanyan <rreverser@google.com>
Date: Wed, 12 Feb 2020 19:51:30 +0000
Subject: Fix std::fs::copy on WASI target

Previously `std::fs::copy` on wasm32-wasi would reuse code from the `sys_common` module and would successfully copy contents of the file just to fail right before closing it.

This was happening because `sys_common::copy` tries to copy permissions of the file, but permissions are not a thing in WASI (at least yet) and `set_permissions` is implemented as an unconditional runtime error.

This change instead adds a custom working implementation of `std::fs::copy` (like Rust already has on some other targets) that doesn't try to call `set_permissions` and is essentially a thin wrapper around `std::io::copy`.

Fixes #68560.
---
 src/libstd/sys/wasi/fs.rs | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

(limited to 'src/libstd')

diff --git a/src/libstd/sys/wasi/fs.rs b/src/libstd/sys/wasi/fs.rs
index 04bfdf67e12..a11f61fdd69 100644
--- a/src/libstd/sys/wasi/fs.rs
+++ b/src/libstd/sys/wasi/fs.rs
@@ -12,7 +12,6 @@ use crate::sys::time::SystemTime;
 use crate::sys::unsupported;
 use crate::sys_common::FromInner;
 
-pub use crate::sys_common::fs::copy;
 pub use crate::sys_common::fs::remove_dir_all;
 
 pub struct File {
@@ -647,3 +646,12 @@ fn open_parent(p: &Path) -> io::Result<(ManuallyDrop<WasiFd>, PathBuf)> {
 pub fn osstr2str(f: &OsStr) -> io::Result<&str> {
     f.to_str().ok_or_else(|| io::Error::new(io::ErrorKind::Other, "input must be utf-8"))
 }
+
+pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
+    use crate::fs::File;
+
+    let mut reader = File::open(from)?;
+    let mut writer = File::create(to)?;
+
+    io::copy(&mut reader, &mut writer)
+}
-- 
cgit 1.4.1-3-g733a5