Deny more windows unsafe_op_in_unsafe_fn

Author: ChrisDenton

Diff for: std/src/sys/os_str/wtf8.rs

@@ -1,5 +1,6 @@
 //! The underlying OsString/OsStr implementation on Windows is a
 //! wrapper around the "WTF-8" encoding; see the `wtf8` module for more.
+#![deny(unsafe_op_in_unsafe_fn)]
 
 use crate::borrow::Cow;
 use crate::collections::TryReserveError;
@@ -71,7 +72,7 @@ impl Buf {
 
     #[inline]
     pub unsafe fn from_encoded_bytes_unchecked(s: Vec<u8>) -> Self {
-        Self { inner: Wtf8Buf::from_bytes_unchecked(s) }
+        unsafe { Self { inner: Wtf8Buf::from_bytes_unchecked(s) } }
     }
 
     pub fn with_capacity(capacity: usize) -> Buf {
@@ -190,7 +191,7 @@ impl Slice {
 
     #[inline]
     pub unsafe fn from_encoded_bytes_unchecked(s: &[u8]) -> &Slice {
-        mem::transmute(Wtf8::from_bytes_unchecked(s))
+        unsafe { mem::transmute(Wtf8::from_bytes_unchecked(s)) }
     }
 
     #[track_caller]

Diff for: std/src/sys/pal/windows/alloc.rs

@@ -1,5 +1,3 @@
-#![deny(unsafe_op_in_unsafe_fn)]
-
 use crate::alloc::{GlobalAlloc, Layout, System};
 use crate::ffi::c_void;
 use crate::ptr;

Diff for: std/src/sys/pal/windows/fs.rs

@@ -1,4 +1,3 @@
-#![allow(unsafe_op_in_unsafe_fn)]
 use core::ptr::addr_of;
 
 use crate::os::windows::prelude::*;
@@ -795,10 +794,12 @@ impl<'a> Iterator for DirBuffIter<'a> {
 }
 
 unsafe fn from_maybe_unaligned<'a>(p: *const u16, len: usize) -> Cow<'a, [u16]> {
-    if p.is_aligned() {
-        Cow::Borrowed(crate::slice::from_raw_parts(p, len))
-    } else {
-        Cow::Owned((0..len).map(|i| p.add(i).read_unaligned()).collect())
+    unsafe {
+        if p.is_aligned() {
+            Cow::Borrowed(crate::slice::from_raw_parts(p, len))
+        } else {
+            Cow::Owned((0..len).map(|i| p.add(i).read_unaligned()).collect())
+        }
     }
 }
 
@@ -897,7 +898,9 @@ impl IntoRawHandle for File {
 
 impl FromRawHandle for File {
     unsafe fn from_raw_handle(raw_handle: RawHandle) -> Self {
-        Self { handle: FromInner::from_inner(FromRawHandle::from_raw_handle(raw_handle)) }
+        unsafe {
+            Self { handle: FromInner::from_inner(FromRawHandle::from_raw_handle(raw_handle)) }
+        }
     }
 }
 
@@ -1427,10 +1430,12 @@ pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
         _hDestinationFile: c::HANDLE,
         lpData: *const c_void,
     ) -> u32 {
-        if dwStreamNumber == 1 {
-            *(lpData as *mut i64) = StreamBytesTransferred;
+        unsafe {
+            if dwStreamNumber == 1 {
+                *(lpData as *mut i64) = StreamBytesTransferred;
+            }
+            c::PROGRESS_CONTINUE
         }
-        c::PROGRESS_CONTINUE
     }
     let pfrom = maybe_verbatim(from)?;
     let pto = maybe_verbatim(to)?;

Diff for: std/src/sys/pal/windows/handle.rs

@@ -1,5 +1,4 @@
 #![unstable(issue = "none", feature = "windows_handle")]
-#![allow(unsafe_op_in_unsafe_fn)]
 
 #[cfg(test)]
 mod tests;
@@ -73,7 +72,7 @@ impl IntoRawHandle for Handle {
 
 impl FromRawHandle for Handle {
     unsafe fn from_raw_handle(raw_handle: RawHandle) -> Self {
-        Self(FromRawHandle::from_raw_handle(raw_handle))
+        unsafe { Self(FromRawHandle::from_raw_handle(raw_handle)) }
     }
 }
 
@@ -142,19 +141,23 @@ impl Handle {
         buf: &mut [u8],
         overlapped: *mut c::OVERLAPPED,
     ) -> io::Result<Option<usize>> {
-        let len = cmp::min(buf.len(), u32::MAX as usize) as u32;
-        let mut amt = 0;
-        let res =
-            cvt(c::ReadFile(self.as_raw_handle(), buf.as_mut_ptr(), len, &mut amt, overlapped));
-        match res {
-            Ok(_) => Ok(Some(amt as usize)),
-            Err(e) => {
-                if e.raw_os_error() == Some(c::ERROR_IO_PENDING as i32) {
-                    Ok(None)
-                } else if e.raw_os_error() == Some(c::ERROR_BROKEN_PIPE as i32) {
-                    Ok(Some(0))
-                } else {
-                    Err(e)
+        // SAFETY: We have exclusive access to the buffer and it's up to the caller to
+        // ensure the OVERLAPPED pointer is valid for the lifetime of this function.
+        unsafe {
+            let len = cmp::min(buf.len(), u32::MAX as usize) as u32;
+            let mut amt = 0;
+            let res =
+                cvt(c::ReadFile(self.as_raw_handle(), buf.as_mut_ptr(), len, &mut amt, overlapped));
+            match res {
+                Ok(_) => Ok(Some(amt as usize)),
+                Err(e) => {
+                    if e.raw_os_error() == Some(c::ERROR_IO_PENDING as i32) {
+                        Ok(None)
+                    } else if e.raw_os_error() == Some(c::ERROR_BROKEN_PIPE as i32) {
+                        Ok(Some(0))
+                    } else {
+                        Err(e)
+                    }
                 }
             }
         }
@@ -230,20 +233,24 @@ impl Handle {
 
         // The length is clamped at u32::MAX.
         let len = cmp::min(len, u32::MAX as usize) as u32;
-        let status = c::NtReadFile(
-            self.as_handle(),
-            ptr::null_mut(),
-            None,
-            ptr::null_mut(),
-            &mut io_status,
-            buf,
-            len,
-            offset.map(|n| n as _).as_ref(),
-            None,
-        );
+        // SAFETY: It's up to the caller to ensure `buf` is writeable up to
+        // the provided `len`.
+        let status = unsafe {
+            c::NtReadFile(
+                self.as_handle(),
+                ptr::null_mut(),
+                None,
+                ptr::null_mut(),
+                &mut io_status,
+                buf,
+                len,
+                offset.map(|n| n as _).as_ref(),
+                None,
+            )
+        };
 
         let status = if status == c::STATUS_PENDING {
-            c::WaitForSingleObject(self.as_raw_handle(), c::INFINITE);
+            unsafe { c::WaitForSingleObject(self.as_raw_handle(), c::INFINITE) };
             io_status.status()
         } else {
             status
@@ -261,7 +268,7 @@ impl Handle {
             status if c::nt_success(status) => Ok(io_status.Information),
 
             status => {
-                let error = c::RtlNtStatusToDosError(status);
+                let error = unsafe { c::RtlNtStatusToDosError(status) };
                 Err(io::Error::from_raw_os_error(error as _))
             }
         }

Diff for: std/src/sys/pal/windows/os.rs

@@ -1,7 +1,6 @@
 //! Implementation of `std::os` functionality for Windows.
 
 #![allow(nonstandard_style)]
-#![allow(unsafe_op_in_unsafe_fn)]
 
 #[cfg(test)]
 mod tests;
@@ -305,15 +304,21 @@ pub fn getenv(k: &OsStr) -> Option<OsString> {
 }
 
 pub unsafe fn setenv(k: &OsStr, v: &OsStr) -> io::Result<()> {
-    let k = to_u16s(k)?;
-    let v = to_u16s(v)?;
+    // SAFETY: We ensure that k and v are null-terminated wide strings.
+    unsafe {
+        let k = to_u16s(k)?;
+        let v = to_u16s(v)?;
 
-    cvt(c::SetEnvironmentVariableW(k.as_ptr(), v.as_ptr())).map(drop)
+        cvt(c::SetEnvironmentVariableW(k.as_ptr(), v.as_ptr())).map(drop)
+    }
 }
 
 pub unsafe fn unsetenv(n: &OsStr) -> io::Result<()> {
-    let v = to_u16s(n)?;
-    cvt(c::SetEnvironmentVariableW(v.as_ptr(), ptr::null())).map(drop)
+    // SAFETY: We ensure that v is a null-terminated wide strings.
+    unsafe {
+        let v = to_u16s(n)?;
+        cvt(c::SetEnvironmentVariableW(v.as_ptr(), ptr::null())).map(drop)
+    }
 }
 
 pub fn temp_dir() -> PathBuf {