Rollup merge of rust-lang#128131 - ChrisDenton:stuff, r=workingjubilee

Import `c_void` rather than using the full path

Follow up to rust-lang#128092. As requested, this imports `c_void` in more places. I also fixed up some imports to use `core` for core types instead of `crate`. While that is not strictly necessary, I think ideally things in `sys/pal` should only depend on itself or core so that the code is less spaghetti. We're far away from that ideal at the moment but I can at least try to slowly move in that direction.

Also this forbids `unsafe_op_in_unsafe_fn` for library/std/src/sys/pal/windows by fixing up the remaining unsafe bits that are just punting their unsafe requirements onto the caller of the `unsafe` function (or definition macro).

<!--
r? workingjubilee
-->

std/src/sys/pal/windows/alloc.rs

@@ -37,7 +37,7 @@ windows_targets::link!("kernel32.dll" "system" fn GetProcessHeap() -> c::HANDLE)
 // Note that `dwBytes` is allowed to be zero, contrary to some other allocators.
 //
 // See https://docs.microsoft.com/windows/win32/api/heapapi/nf-heapapi-heapalloc
-windows_targets::link!("kernel32.dll" "system" fn HeapAlloc(hheap: c::HANDLE, dwflags: u32, dwbytes: usize) -> *mut core::ffi::c_void);
+windows_targets::link!("kernel32.dll" "system" fn HeapAlloc(hheap: c::HANDLE, dwflags: u32, dwbytes: usize) -> *mut c_void);
 
 // Reallocate a block of memory behind a given pointer `lpMem` from a given heap `hHeap`,
 // to a block of at least `dwBytes` bytes, either shrinking the block in place,
@@ -61,9 +61,9 @@ windows_targets::link!("kernel32.dll" "system" fn HeapAlloc(hheap: c::HANDLE, dw
 windows_targets::link!("kernel32.dll" "system" fn HeapReAlloc(
     hheap: c::HANDLE,
     dwflags : u32,
-    lpmem: *const core::ffi::c_void,
+    lpmem: *const c_void,
     dwbytes: usize
-) -> *mut core::ffi::c_void);
+) -> *mut c_void);
 
 // Free a block of memory behind a given pointer `lpMem` from a given heap `hHeap`.
 // Returns a nonzero value if the operation is successful, and zero if the operation fails.
@@ -79,7 +79,7 @@ windows_targets::link!("kernel32.dll" "system" fn HeapReAlloc(
 // Note that `lpMem` is allowed to be null, which will not cause the operation to fail.
 //
 // See https://docs.microsoft.com/windows/win32/api/heapapi/nf-heapapi-heapfree
-windows_targets::link!("kernel32.dll" "system" fn HeapFree(hheap: c::HANDLE, dwflags: u32, lpmem: *const core::ffi::c_void) -> c::BOOL);
+windows_targets::link!("kernel32.dll" "system" fn HeapFree(hheap: c::HANDLE, dwflags: u32, lpmem: *const c_void) -> c::BOOL);
 
 // Cached handle to the default heap of the current process.
 // Either a non-null handle returned by `GetProcessHeap`, or null when not yet initialized or `GetProcessHeap` failed.

std/src/sys/pal/windows/c.rs

@@ -4,12 +4,10 @@
 #![cfg_attr(test, allow(dead_code))]
 #![unstable(issue = "none", feature = "windows_c")]
 #![allow(clippy::style)]
-#![allow(unsafe_op_in_unsafe_fn)]
 
-use crate::ffi::CStr;
-use crate::mem;
-use crate::os::raw::{c_uint, c_ulong, c_ushort, c_void};
-use crate::ptr;
+use core::ffi::{c_uint, c_ulong, c_ushort, c_void, CStr};
+use core::mem;
+use core::ptr;
 
 pub(super) mod windows_targets;
 
@@ -136,26 +134,26 @@ compat_fn_with_fallback! {
     // >= Win10 1607
     // https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-setthreaddescription
     pub fn SetThreadDescription(hthread: HANDLE, lpthreaddescription: PCWSTR) -> HRESULT {
-        SetLastError(ERROR_CALL_NOT_IMPLEMENTED as u32); E_NOTIMPL
+        unsafe { SetLastError(ERROR_CALL_NOT_IMPLEMENTED as u32); E_NOTIMPL }
     }
 
     // >= Win10 1607
     // https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-getthreaddescription
     pub fn GetThreadDescription(hthread: HANDLE, lpthreaddescription: *mut PWSTR) -> HRESULT {
-        SetLastError(ERROR_CALL_NOT_IMPLEMENTED as u32); E_NOTIMPL
+        unsafe { SetLastError(ERROR_CALL_NOT_IMPLEMENTED as u32); E_NOTIMPL }
     }
 
     // >= Win8 / Server 2012
     // https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-getsystemtimepreciseasfiletime
     #[cfg(target_vendor = "win7")]
     pub fn GetSystemTimePreciseAsFileTime(lpsystemtimeasfiletime: *mut FILETIME) -> () {
-        GetSystemTimeAsFileTime(lpsystemtimeasfiletime)
+        unsafe { GetSystemTimeAsFileTime(lpsystemtimeasfiletime) }
     }
 
     // >= Win11 / Server 2022
     // https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-gettemppath2a
     pub fn GetTempPath2W(bufferlength: u32, buffer: PWSTR) -> u32 {
-        GetTempPathW(bufferlength, buffer)
+        unsafe {  GetTempPathW(bufferlength, buffer) }
     }
 }
 
@@ -188,12 +186,12 @@ extern "system" {
 compat_fn_optional! {
     crate::sys::compat::load_synch_functions();
     pub fn WaitOnAddress(
-        address: *const ::core::ffi::c_void,
-        compareaddress: *const ::core::ffi::c_void,
+        address: *const c_void,
+        compareaddress: *const c_void,
         addresssize: usize,
         dwmilliseconds: u32
     ) -> BOOL;
-    pub fn WakeByAddressSingle(address: *const ::core::ffi::c_void);
+    pub fn WakeByAddressSingle(address: *const c_void);
 }
 
 #[cfg(any(target_vendor = "win7", target_vendor = "uwp"))]
@@ -240,7 +238,7 @@ compat_fn_with_fallback! {
         shareaccess: FILE_SHARE_MODE,
         createdisposition: NTCREATEFILE_CREATE_DISPOSITION,
         createoptions: NTCREATEFILE_CREATE_OPTIONS,
-        eabuffer: *const ::core::ffi::c_void,
+        eabuffer: *const c_void,
         ealength: u32
     ) -> NTSTATUS {
         STATUS_NOT_IMPLEMENTED
@@ -250,9 +248,9 @@ compat_fn_with_fallback! {
         filehandle: HANDLE,
         event: HANDLE,
         apcroutine: PIO_APC_ROUTINE,
-        apccontext: *const core::ffi::c_void,
+        apccontext: *const c_void,
         iostatusblock: *mut IO_STATUS_BLOCK,
-        buffer: *mut core::ffi::c_void,
+        buffer: *mut c_void,
         length: u32,
         byteoffset: *const i64,
         key: *const u32
@@ -264,9 +262,9 @@ compat_fn_with_fallback! {
         filehandle: HANDLE,
         event: HANDLE,
         apcroutine: PIO_APC_ROUTINE,
-        apccontext: *const core::ffi::c_void,
+        apccontext: *const c_void,
         iostatusblock: *mut IO_STATUS_BLOCK,
-        buffer: *const core::ffi::c_void,
+        buffer: *const c_void,
         length: u32,
         byteoffset: *const i64,
         key: *const u32

std/src/sys/pal/windows/compat.rs

@@ -158,8 +158,10 @@ macro_rules! compat_fn_with_fallback {
             static PTR: AtomicPtr<c_void> = AtomicPtr::new(load as *mut _);
 
             unsafe extern "system" fn load($($argname: $argtype),*) -> $rettype {
-                let func = load_from_module(Module::new($module));
-                func($($argname),*)
+                unsafe {
+                    let func = load_from_module(Module::new($module));
+                    func($($argname),*)
+                }
             }
 
             fn load_from_module(module: Option<Module>) -> F {
@@ -182,8 +184,10 @@ macro_rules! compat_fn_with_fallback {
 
             #[inline(always)]
             pub unsafe fn call($($argname: $argtype),*) -> $rettype {
-                let func: F = mem::transmute(PTR.load(Ordering::Relaxed));
-                func($($argname),*)
+                unsafe {
+                    let func: F = mem::transmute(PTR.load(Ordering::Relaxed));
+                    func($($argname),*)
+                }
             }
         }
         #[allow(unused)]
@@ -225,7 +229,7 @@ macro_rules! compat_fn_optional {
             }
             #[inline]
             pub unsafe extern "system" fn $symbol($($argname: $argtype),*) $(-> $rettype)? {
-                $symbol::option().unwrap()($($argname),*)
+                unsafe { $symbol::option().unwrap()($($argname),*) }
             }
         )+
     )

std/src/sys/pal/windows/handle.rs

@@ -3,16 +3,17 @@
 #[cfg(test)]
 mod tests;
 
-use crate::cmp;
 use crate::io::{self, BorrowedCursor, ErrorKind, IoSlice, IoSliceMut, Read};
-use crate::mem;
 use crate::os::windows::io::{
     AsHandle, AsRawHandle, BorrowedHandle, FromRawHandle, IntoRawHandle, OwnedHandle, RawHandle,
 };
-use crate::ptr;
 use crate::sys::c;
 use crate::sys::cvt;
 use crate::sys_common::{AsInner, FromInner, IntoInner};
+use core::cmp;
+use core::ffi::c_void;
+use core::mem;
+use core::ptr;
 
 /// An owned container for `HANDLE` object, closing them on Drop.
 ///
@@ -255,7 +256,7 @@ impl Handle {
                 None,
                 ptr::null_mut(),
                 &mut io_status,
-                buf.cast::<core::ffi::c_void>(),
+                buf.cast::<c_void>(),
                 len,
                 offset.as_ref().map(|n| ptr::from_ref(n).cast::<i64>()).unwrap_or(ptr::null()),
                 ptr::null(),
@@ -305,7 +306,7 @@ impl Handle {
                 None,
                 ptr::null_mut(),
                 &mut io_status,
-                buf.as_ptr().cast::<core::ffi::c_void>(),
+                buf.as_ptr().cast::<c_void>(),
                 len,
                 offset.as_ref().map(|n| ptr::from_ref(n).cast::<i64>()).unwrap_or(ptr::null()),
                 ptr::null(),

std/src/sys/pal/windows/mod.rs

@@ -1,5 +1,5 @@
 #![allow(missing_docs, nonstandard_style)]
-#![deny(unsafe_op_in_unsafe_fn)]
+#![forbid(unsafe_op_in_unsafe_fn)]
 
 use crate::ffi::{OsStr, OsString};
 use crate::io::ErrorKind;