Reimplement Win32 APIs for GetFileInformationByHandleEx and SetFileInformationByHandle

Reimplement them on-top of native NT APIs as done in `fileextd.lib`.
This allows more file system APIs to work on XP and below.

Affected APIs:
- File truncation (can now set end of file without multiple SetFilePointerEx calls on NT)
- Cleaner fallback impl for reparse tags
- remove_dir_all: Modern impl now supported on all NT-based systems

Author: seritools

library/std/src/sys/fs/windows.rs

@@ -591,7 +591,7 @@ impl File {
 
     #[cfg(target_family = "rust9x")]
     pub fn truncate_inner(handle: RawHandle, size: u64) -> io::Result<()> {
-        if c::SetFileInformationByHandle::available().is_some() {
+        if crate::sys::compat::checks::is_windows_nt() {
             let info = c::FILE_END_OF_FILE_INFO { EndOfFile: size as i64 };
             api::set_file_information_by_handle(handle, &info).io_result()
         } else {
@@ -620,22 +620,20 @@ impl File {
             cvt(c::GetFileInformationByHandle(self.handle.as_raw_handle(), &mut info))?;
             let mut reparse_tag = 0;
             if info.dwFileAttributes & c::FILE_ATTRIBUTE_REPARSE_POINT != 0 {
-                #[cfg(target_family = "rust9x")]
-                let f = c::GetFileInformationByHandleEx::available();
-                #[cfg(not(target_family = "rust9x"))]
-                let f = Some(c::GetFileInformationByHandleEx);
-
-                if let Some(f) = f {
-                    let mut attr_tag: c::FILE_ATTRIBUTE_TAG_INFO = mem::zeroed();
-                    cvt(f(
-                        self.handle.as_raw_handle(),
-                        c::FileAttributeTagInfo,
-                        (&raw mut attr_tag).cast(),
-                        size_of::<c::FILE_ATTRIBUTE_TAG_INFO>().try_into().unwrap(),
-                    ))?;
-                    if attr_tag.FileAttributes & c::FILE_ATTRIBUTE_REPARSE_POINT != 0 {
-                        reparse_tag = attr_tag.ReparseTag;
-                    }
+                let mut attr_tag: c::FILE_ATTRIBUTE_TAG_INFO = mem::zeroed();
+                // rust9x: If a reparse point attribute is returned, we must be on NT-based Windows
+                // with support for FileAttributeTagInformation, so our
+                // fallback implementation of `GetFileInformationByHandleEx` will work without
+                // further checks.
+
+                cvt(c::GetFileInformationByHandleEx(
+                    self.handle.as_raw_handle(),
+                    c::FileAttributeTagInfo,
+                    (&raw mut attr_tag).cast(),
+                    mem::size_of::<c::FILE_ATTRIBUTE_TAG_INFO>().try_into().unwrap(),
+                ))?;
+                if attr_tag.FileAttributes & c::FILE_ATTRIBUTE_REPARSE_POINT != 0 {
+                    reparse_tag = attr_tag.ReparseTag;
                 }
             }
             Ok(FileAttr {
@@ -988,6 +986,10 @@ impl File {
     /// you will always iterate an empty directory regardless of the target.
     #[allow(unused)]
     fn fill_dir_buff(&self, buffer: &mut DirBuff, restart: bool) -> Result<bool, WinError> {
+        #[cfg(target_family = "rust9x")]
+        let class =
+            if restart { c::FileFullDirectoryRestartInfo } else { c::FileFullDirectoryInfo };
+        #[cfg(not(target_family = "rust9x"))]
         let class =
             if restart { c::FileIdBothDirectoryRestartInfo } else { c::FileIdBothDirectoryInfo };
 
@@ -1064,6 +1066,9 @@ impl<'a> Iterator for DirBuffIter<'a> {
         //   `FILE_ID_BOTH_DIR_INFO` and the trailing filename (for at least
         //   `FileNameLength` bytes)
         let (name, is_directory, next_entry) = unsafe {
+            #[cfg(target_family = "rust9x")]
+            let info = buffer.as_ptr().cast::<c::FILE_FULL_DIR_INFO>();
+            #[cfg(not(target_family = "rust9x"))]
             let info = buffer.as_ptr().cast::<c::FILE_ID_BOTH_DIR_INFO>();
             // While this is guaranteed to be aligned in documentation for
             // https://docs.microsoft.com/en-us/windows/win32/api/winbase/ns-winbase-file_id_both_dir_info
@@ -1503,12 +1508,10 @@ pub fn remove_dir_all(p: &Path) -> io::Result<()> {
     use crate::sys::path::with_native_path;
 
     with_native_path(p, &|path| {
-        // if the modern file/directory APIs are not available, we'll fall back to the old (unsafe, see
-        // https://github.com/rust-lang/rust/pull/93112) directory removal implementation
-        if !(c::NtOpenFile::available().is_some()
-            && c::GetFileInformationByHandleEx::available().is_some()
-            && c::SetFileInformationByHandle::available().is_some())
-        {
+        // if the modern file/directory APIs are not available (9x/Me), we'll fall back to the old
+        // (unsafe, see https://github.com/rust-lang/rust/pull/93112) directory removal
+        // implementation
+        if !crate::sys::compat::checks::is_windows_nt() {
             let filetype = lstat(path)?.file_type();
             if filetype.is_symlink() {
                 // On Windows symlinks to files and directories are removed differently.

library/std/src/sys/io/is_terminal/windows.rs

@@ -42,10 +42,11 @@ fn msys_tty_on(handle: BorrowedHandle<'_>) -> bool {
     // Safety: buffer length is fixed.
     let res = unsafe {
         #[cfg(target_family = "rust9x")]
-        let Some(fun) = c::GetFileInformationByHandleEx::available() else { return false };
-        #[cfg(not(target_family = "rust9x"))]
-        let fun = c::GetFileInformationByHandleEx;
-        fun(
+        if !crate::sys::compat::checks::is_windows_nt() {
+            return false;
+        }
+
+        c::GetFileInformationByHandleEx(
             handle.as_raw_handle(),
             c::FileNameInfo,
             (&raw mut name_info) as *mut c_void,

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

@@ -12,6 +12,8 @@ use core::ptr;
 mod windows_sys;
 pub use windows_sys::*;
 
+#[cfg(target_family = "rust9x")]
+pub(crate) mod fileextd;
 #[cfg(target_family = "rust9x")]
 pub(crate) mod wspiapi;
 
@@ -485,29 +487,6 @@ compat_fn_with_fallback! {
             TRUE
         }
     }
-
-    // >= Vista / Server 2008 (XP / Server 2003 when linking a supported FileExtd.lib)
-    // https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-setfileinformationbyhandle
-    pub fn SetFileInformationByHandle(
-        hfile: HANDLE,
-        fileinformationclass: FILE_INFO_BY_HANDLE_CLASS,
-        lpfileinformation: *const ::core::ffi::c_void,
-        dwbuffersize: u32,
-    ) -> BOOL {
-        unsafe { SetLastError(ERROR_CALL_NOT_IMPLEMENTED as u32); };
-        FALSE
-    }
-    // >= Vista / Server 2008 (XP / Server 2003 when linking a supported FileExtd.lib)
-    // https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-getfileinformationbyhandleex
-    pub fn GetFileInformationByHandleEx(
-        hfile: HANDLE,
-        fileinformationclass: FILE_INFO_BY_HANDLE_CLASS,
-        lpfileinformation: *mut ::core::ffi::c_void,
-        dwbuffersize: u32,
-    ) -> BOOL {
-        unsafe { SetLastError(ERROR_CALL_NOT_IMPLEMENTED as u32); };
-        FALSE
-    }
 }
 
 #[cfg(target_family = "rust9x")]
@@ -769,3 +748,55 @@ compat_fn_with_fallback! {
         FALSE
     }
 }
+
+#[cfg(target_family = "rust9x")]
+pub(crate) use fileextd::{
+    get_file_information_by_handle_ex as GetFileInformationByHandleEx,
+    set_file_information_by_handle as SetFileInformationByHandle,
+};
+
+#[cfg(target_family = "rust9x")]
+compat_fn_with_fallback! {
+    pub static NTDLL: &CStr = c"ntdll" => { load: false, unicows: false };
+    // all NT only
+    fn NtQueryDirectoryFile(
+        filehandle: HANDLE,
+        event: HANDLE,
+        apcroutine: PIO_APC_ROUTINE,
+        apccontext: *const core::ffi::c_void,
+        iostatusblock: *mut IO_STATUS_BLOCK,
+        fileinformation: *mut core::ffi::c_void,
+        length: u32,
+        fileinformationclass: FILE_INFORMATION_CLASS,
+        returnsingleentry: bool,
+        filename: *const UNICODE_STRING,
+        restartscan: bool
+    ) -> NTSTATUS {
+        rtabort!("unimplemented")
+    }
+    fn NtQueryInformationFile(
+        filehandle: HANDLE,
+        iostatusblock: *mut IO_STATUS_BLOCK,
+        fileinformation: *mut core::ffi::c_void,
+        length: u32,
+        fileinformationclass: FILE_INFORMATION_CLASS
+    ) -> NTSTATUS {
+        rtabort!("unimplemented")
+    }
+    fn NtSetInformationFile(
+        filehandle: HANDLE,
+        iostatusblock: *mut IO_STATUS_BLOCK,
+        fileinformation: *const core::ffi::c_void,
+        length: u32,
+        fileinformationclass: FILE_INFORMATION_CLASS
+    ) -> NTSTATUS {
+        rtabort!("unimplemented")
+    }
+    fn NtWaitForSingleObject(
+        handle: HANDLE,
+        alertable: bool,
+        timeout: *mut i64
+    ) -> NTSTATUS {
+        rtabort!("unimplemented")
+    }
+}

library/std/src/sys/pal/windows/c/bindings.txt

@@ -2047,13 +2047,16 @@ FILE_FLAG_SEQUENTIAL_SCAN
 FILE_FLAG_SESSION_AWARE
 FILE_FLAG_WRITE_THROUGH
 FILE_FLAGS_AND_ATTRIBUTES
+FILE_FULL_DIR_INFO
 FILE_GENERIC_EXECUTE
 FILE_GENERIC_READ
 FILE_GENERIC_WRITE
 FILE_ID_BOTH_DIR_INFO
 FILE_INFO_BY_HANDLE_CLASS
+FILE_INFORMATION_CLASS
 FILE_IO_PRIORITY_HINT_INFO
 FILE_LIST_DIRECTORY
+FILE_NAME_INFO
 FILE_NAME_NORMALIZED
 FILE_NAME_OPENED
 FILE_NO_EA_KNOWLEDGE
@@ -2109,13 +2112,19 @@ FILE_WRITE_THROUGH
 FileAlignmentInfo
 FileAllocationInfo
 FileAttributeTagInfo
+FileAttributeTagInformation
 FileBasicInfo
+FileBasicInformation
 FileCaseSensitiveInfo
 FileCompressionInfo
 FileDispositionInfo
 FileDispositionInfoEx
+FileDispositionInformation
+FileDispositionInformationEx
 FileEndOfFileInfo
+FileEndOfFileInformation
 FileFullDirectoryInfo
+FileFullDirectoryInformation
 FileFullDirectoryRestartInfo
 FileIdBothDirectoryInfo
 FileIdBothDirectoryRestartInfo
@@ -2124,6 +2133,7 @@ FileIdExtdDirectoryRestartInfo
 FileIdInfo
 FileIoPriorityHintInfo
 FileNameInfo
+FileNameInformation
 FileNormalizedNameInfo
 FileRemoteProtocolInfo
 FileRenameInfo
@@ -2324,8 +2334,12 @@ NtCreateFile
 NTCREATEFILE_CREATE_DISPOSITION
 NTCREATEFILE_CREATE_OPTIONS
 NtOpenFile
+NtQueryDirectoryFile
+NtQueryInformationFile
 NtReadFile
+NtSetInformationFile
 NTSTATUS
+NtWaitForSingleObject
 NtWriteFile
 OBJ_CASE_INSENSITIVE
 OBJ_DONT_REPARSE