Rollup merge of rust-lang#143592 - ChrisDenton:uwp-link, r=Mark-Simulacrum

UWP: link ntdll functions using raw-dylib

Lazy loading isn't necessary so there's no need for the added complexity and overhead. However, it may be that people using UWP rust libraries don't have the necessary import libraries linked by Visual Studio so this uses raw-dylib, which allows linking to DLL functions without having an import library. This is a somewhat temporary situation as raw-dylib is intended to eventually be the default for all imports. When that happens, this special case can be removed.

Closes rust-lang#143530

Author: fmease

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

@@ -197,7 +197,7 @@ compat_fn_optional! {
     pub fn WakeByAddressSingle(address: *const c_void);
 }
 
-#[cfg(any(target_vendor = "win7", target_vendor = "uwp"))]
+#[cfg(any(target_vendor = "win7"))]
 compat_fn_with_fallback! {
     pub static NTDLL: &CStr = c"ntdll";
 
@@ -228,65 +228,14 @@ compat_fn_with_fallback! {
     ) -> NTSTATUS {
         panic!("keyed events not available")
     }
+}
 
-    // These functions are available on UWP when lazily loaded. They will fail WACK if loaded statically.
-    #[cfg(target_vendor = "uwp")]
-    pub fn NtCreateFile(
-        filehandle: *mut HANDLE,
-        desiredaccess: FILE_ACCESS_RIGHTS,
-        objectattributes: *const OBJECT_ATTRIBUTES,
-        iostatusblock: *mut IO_STATUS_BLOCK,
-        allocationsize: *const i64,
-        fileattributes: FILE_FLAGS_AND_ATTRIBUTES,
-        shareaccess: FILE_SHARE_MODE,
-        createdisposition: NTCREATEFILE_CREATE_DISPOSITION,
-        createoptions: NTCREATEFILE_CREATE_OPTIONS,
-        eabuffer: *const c_void,
-        ealength: u32
-    ) -> NTSTATUS {
-        STATUS_NOT_IMPLEMENTED
-    }
-    #[cfg(target_vendor = "uwp")]
-    pub fn NtOpenFile(
-        filehandle: *mut HANDLE,
-        desiredaccess: u32,
-        objectattributes: *const OBJECT_ATTRIBUTES,
-        iostatusblock: *mut IO_STATUS_BLOCK,
-        shareaccess: u32,
-        openoptions: u32
-    ) -> NTSTATUS {
-        STATUS_NOT_IMPLEMENTED
-    }
-    #[cfg(target_vendor = "uwp")]
-    pub fn NtReadFile(
-        filehandle: HANDLE,
-        event: HANDLE,
-        apcroutine: PIO_APC_ROUTINE,
-        apccontext: *const c_void,
-        iostatusblock: *mut IO_STATUS_BLOCK,
-        buffer: *mut c_void,
-        length: u32,
-        byteoffset: *const i64,
-        key: *const u32
-    ) -> NTSTATUS {
-        STATUS_NOT_IMPLEMENTED
-    }
-    #[cfg(target_vendor = "uwp")]
-    pub fn NtWriteFile(
-        filehandle: HANDLE,
-        event: HANDLE,
-        apcroutine: PIO_APC_ROUTINE,
-        apccontext: *const c_void,
-        iostatusblock: *mut IO_STATUS_BLOCK,
-        buffer: *const c_void,
-        length: u32,
-        byteoffset: *const i64,
-        key: *const u32
-    ) -> NTSTATUS {
-        STATUS_NOT_IMPLEMENTED
-    }
-    #[cfg(target_vendor = "uwp")]
-    pub fn RtlNtStatusToDosError(Status: NTSTATUS) -> u32 {
-        Status as u32
+cfg_if::cfg_if! {
+    if #[cfg(target_vendor = "uwp")] {
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn NtCreateFile(filehandle : *mut HANDLE, desiredaccess : FILE_ACCESS_RIGHTS, objectattributes : *const OBJECT_ATTRIBUTES, iostatusblock : *mut IO_STATUS_BLOCK, allocationsize : *const i64, fileattributes : FILE_FLAGS_AND_ATTRIBUTES, shareaccess : FILE_SHARE_MODE, createdisposition : NTCREATEFILE_CREATE_DISPOSITION, createoptions : NTCREATEFILE_CREATE_OPTIONS, eabuffer : *const core::ffi::c_void, ealength : u32) -> NTSTATUS);
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn NtOpenFile(filehandle : *mut HANDLE, desiredaccess : u32, objectattributes : *const OBJECT_ATTRIBUTES, iostatusblock : *mut IO_STATUS_BLOCK, shareaccess : u32, openoptions : u32) -> NTSTATUS);
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn NtReadFile(filehandle : HANDLE, event : HANDLE, apcroutine : PIO_APC_ROUTINE, apccontext : *const core::ffi::c_void, iostatusblock : *mut IO_STATUS_BLOCK, buffer : *mut core::ffi::c_void, length : u32, byteoffset : *const i64, key : *const u32) -> NTSTATUS);
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn NtWriteFile(filehandle : HANDLE, event : HANDLE, apcroutine : PIO_APC_ROUTINE, apccontext : *const core::ffi::c_void, iostatusblock : *mut IO_STATUS_BLOCK, buffer : *const core::ffi::c_void, length : u32, byteoffset : *const i64, key : *const u32) -> NTSTATUS);
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn RtlNtStatusToDosError(status : NTSTATUS) -> u32);
     }
 }

library/windows_targets/src/lib.rs

@@ -7,8 +7,7 @@
 #![feature(decl_macro)]
 #![feature(no_core)]
 
-#[cfg(feature = "windows_raw_dylib")]
-pub macro link {
+pub macro link_raw_dylib {
     ($library:literal $abi:literal $($link_name:literal)? $(#[$doc:meta])? fn $($function:tt)*) => (
         #[cfg_attr(not(target_arch = "x86"), link(name = $library, kind = "raw-dylib", modifiers = "+verbatim"))]
         #[cfg_attr(target_arch = "x86", link(name = $library, kind = "raw-dylib", modifiers = "+verbatim", import_name_type = "undecorated"))]
@@ -18,6 +17,26 @@ pub macro link {
         }
     )
 }
+
+pub macro link_dylib {
+    ($library:literal $abi:literal $($link_name:literal)? $(#[$doc:meta])? fn $($function:tt)*) => (
+        // Note: the windows-targets crate uses a pre-built Windows.lib import library which we don't
+        // have in this repo. So instead we always link kernel32.lib and add the rest of the import
+        // libraries below by using an empty extern block. This works because extern blocks are not
+        // connected to the library given in the #[link] attribute.
+        #[link(name = "kernel32")]
+        unsafe extern $abi {
+            $(#[link_name=$link_name])?
+            pub fn $($function)*;
+        }
+    )
+}
+
+#[cfg(feature = "windows_raw_dylib")]
+pub macro link($($tt:tt)*) {
+    $crate::link_raw_dylib!($($tt)*)
+}
+
 #[cfg(not(feature = "windows_raw_dylib"))]
 pub macro link {
     ($library:literal $abi:literal $($link_name:literal)? $(#[$doc:meta])? fn $($function:tt)*) => (