Merge pull request #4547 from CraftSpider/windows-set-len

Implement SetFileInformationByHandle, as well as direct shim test for it

Author: RalfJung

src/shims/windows/foreign_items.rs

@@ -307,6 +307,12 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let res = this.GetFileInformationByHandle(handle, info)?;
                 this.write_scalar(res, dest)?;
             }
+            "SetFileInformationByHandle" => {
+                let [handle, class, info, size] =
+                    this.check_shim_sig_lenient(abi, sys_conv, link_name, args)?;
+                let res = this.SetFileInformationByHandle(handle, class, info, size)?;
+                this.write_scalar(res, dest)?;
+            }
             "DeleteFileW" => {
                 let [file_name] = this.check_shim_sig_lenient(abi, sys_conv, link_name, args)?;
                 let res = this.DeleteFileW(file_name)?;

src/shims/windows/fs.rs

@@ -5,6 +5,7 @@ use std::path::PathBuf;
 use std::time::SystemTime;
 
 use bitflags::bitflags;
+use rustc_abi::Size;
 use rustc_target::spec::Os;
 
 use crate::shims::files::{FdId, FileDescription, FileHandle};
@@ -372,6 +373,90 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         interp_ok(this.eval_windows("c", "TRUE"))
     }
 
+    fn SetFileInformationByHandle(
+        &mut self,
+        file: &OpTy<'tcx>,             // HANDLE
+        class: &OpTy<'tcx>,            // FILE_INFO_BY_HANDLE_CLASS
+        file_information: &OpTy<'tcx>, // LPVOID
+        buffer_size: &OpTy<'tcx>,      // DWORD
+    ) -> InterpResult<'tcx, Scalar> {
+        // ^ Returns BOOL (i32 on Windows)
+        let this = self.eval_context_mut();
+        this.assert_target_os(Os::Windows, "SetFileInformationByHandle");
+        this.check_no_isolation("`SetFileInformationByHandle`")?;
+
+        let class = this.read_scalar(class)?.to_u32()?;
+        let buffer_size = this.read_scalar(buffer_size)?.to_u32()?;
+        let file_information = this.read_pointer(file_information)?;
+        this.check_ptr_access(
+            file_information,
+            Size::from_bytes(buffer_size),
+            CheckInAllocMsg::MemoryAccess,
+        )?;
+
+        let file = this.read_handle(file, "SetFileInformationByHandle")?;
+        let Handle::File(fd_num) = file else { this.invalid_handle("SetFileInformationByHandle")? };
+        let Some(desc) = this.machine.fds.get(fd_num) else {
+            this.invalid_handle("SetFileInformationByHandle")?
+        };
+        let file = desc.downcast::<FileHandle>().ok_or_else(|| {
+            err_unsup_format!(
+                "`SetFileInformationByHandle` is only supported on file-backed file descriptors"
+            )
+        })?;
+
+        if class == this.eval_windows_u32("c", "FileEndOfFileInfo") {
+            let place = this
+                .ptr_to_mplace(file_information, this.windows_ty_layout("FILE_END_OF_FILE_INFO"));
+            let new_len =
+                this.read_scalar(&this.project_field_named(&place, "EndOfFile")?)?.to_i64()?;
+            match file.file.set_len(new_len.try_into().unwrap()) {
+                Ok(_) => interp_ok(this.eval_windows("c", "TRUE")),
+                Err(e) => {
+                    this.set_last_error(e)?;
+                    interp_ok(this.eval_windows("c", "FALSE"))
+                }
+            }
+        } else if class == this.eval_windows_u32("c", "FileAllocationInfo") {
+            // On Windows, files are somewhat similar to a `Vec` in that they have a separate
+            // "length" (called "EOF position") and "capacity" (called "allocation size").
+            // Growing the allocation size is largely a performance hint which we can
+            // ignore -- it can also be directly queried, but we currently do not support that.
+            // So we only need to do something if this operation shrinks the allocation size
+            // so far that it affects the EOF position.
+            let place = this
+                .ptr_to_mplace(file_information, this.windows_ty_layout("FILE_ALLOCATION_INFO"));
+            let new_alloc_size: u64 = this
+                .read_scalar(&this.project_field_named(&place, "AllocationSize")?)?
+                .to_i64()?
+                .try_into()
+                .unwrap();
+            let old_len = match file.file.metadata() {
+                Ok(m) => m.len(),
+                Err(e) => {
+                    this.set_last_error(e)?;
+                    return interp_ok(this.eval_windows("c", "FALSE"));
+                }
+            };
+            if new_alloc_size < old_len {
+                match file.file.set_len(new_alloc_size) {
+                    Ok(_) => interp_ok(this.eval_windows("c", "TRUE")),
+                    Err(e) => {
+                        this.set_last_error(e)?;
+                        interp_ok(this.eval_windows("c", "FALSE"))
+                    }
+                }
+            } else {
+                interp_ok(this.eval_windows("c", "TRUE"))
+            }
+        } else {
+            throw_unsup_format!(
+                "SetFileInformationByHandle: Unsupported `FileInformationClass` value {}",
+                class
+            )
+        }
+    }
+
     fn DeleteFileW(
         &mut self,
         file_name: &OpTy<'tcx>, // LPCWSTR

tests/pass-dep/shims/windows-fs.rs

@@ -19,9 +19,11 @@ use windows_sys::Win32::Foundation::{
 };
 use windows_sys::Win32::Storage::FileSystem::{
     BY_HANDLE_FILE_INFORMATION, CREATE_ALWAYS, CREATE_NEW, CreateFileW, DeleteFileW,
-    FILE_ATTRIBUTE_DIRECTORY, FILE_ATTRIBUTE_NORMAL, FILE_BEGIN, FILE_CURRENT,
-    FILE_FLAG_BACKUP_SEMANTICS, FILE_FLAG_OPEN_REPARSE_POINT, FILE_SHARE_DELETE, FILE_SHARE_READ,
-    FILE_SHARE_WRITE, GetFileInformationByHandle, OPEN_ALWAYS, OPEN_EXISTING, SetFilePointerEx,
+    FILE_ALLOCATION_INFO, FILE_ATTRIBUTE_DIRECTORY, FILE_ATTRIBUTE_NORMAL, FILE_BEGIN,
+    FILE_CURRENT, FILE_END_OF_FILE_INFO, FILE_FLAG_BACKUP_SEMANTICS, FILE_FLAG_OPEN_REPARSE_POINT,
+    FILE_SHARE_DELETE, FILE_SHARE_READ, FILE_SHARE_WRITE, FileAllocationInfo, FileEndOfFileInfo,
+    GetFileInformationByHandle, OPEN_ALWAYS, OPEN_EXISTING, SetFileInformationByHandle,
+    SetFilePointerEx,
 };
 use windows_sys::Win32::System::IO::IO_STATUS_BLOCK;
 use windows_sys::Win32::System::Threading::GetCurrentProcess;
@@ -37,6 +39,7 @@ fn main() {
         test_ntstatus_to_dos();
         test_file_read_write();
         test_file_seek();
+        test_set_file_info();
         test_dup_handle();
     }
 }
@@ -275,6 +278,32 @@ unsafe fn test_file_read_write() {
     assert_eq!(GetLastError(), 1234);
 }
 
+unsafe fn test_set_file_info() {
+    let temp = utils::tmp().join("test_set_file.txt");
+    let mut file = fs::File::create(&temp).unwrap();
+    let handle = file.as_raw_handle();
+
+    let info = FILE_END_OF_FILE_INFO { EndOfFile: 20 };
+    let res = SetFileInformationByHandle(
+        handle,
+        FileEndOfFileInfo,
+        ptr::from_ref(&info).cast(),
+        size_of::<FILE_END_OF_FILE_INFO>().try_into().unwrap(),
+    );
+    assert!(res != 0);
+    assert_eq!(file.seek(SeekFrom::End(0)).unwrap(), 20);
+
+    let info = FILE_ALLOCATION_INFO { AllocationSize: 0 };
+    let res = SetFileInformationByHandle(
+        handle,
+        FileAllocationInfo,
+        ptr::from_ref(&info).cast(),
+        size_of::<FILE_ALLOCATION_INFO>().try_into().unwrap(),
+    );
+    assert!(res != 0);
+    assert_eq!(file.metadata().unwrap().len(), 0);
+}
+
 unsafe fn test_dup_handle() {
     let temp = utils::tmp().join("test_dup.txt");
 

tests/pass/shims/fs.rs

@@ -28,9 +28,9 @@ fn main() {
     test_errors();
     test_from_raw_os_error();
     test_file_clone();
+    test_file_set_len();
     // Windows file handling is very incomplete.
     if cfg!(not(windows)) {
-        test_file_set_len();
         test_file_sync();
         test_rename();
         test_directory();
@@ -77,6 +77,9 @@ fn test_file() {
     // However, writing 0 bytes can succeed or fail.
     let _ignore = file.write(&[]);
 
+    // Test calling File::create on an existing file, since that uses a different code path
+    File::create(&path).unwrap();
+
     // Removing file should succeed.
     remove_file(&path).unwrap();
 }
@@ -87,7 +90,6 @@ fn test_file_partial_reads_writes() {
 
     // Ensure we sometimes do incomplete writes.
     check_nondet(|| {
-        let _ = remove_file(&path1); // FIXME(win, issue #4483): errors if the file already exists
         let mut file = File::create(&path1).unwrap();
         file.write(&[0; 4]).unwrap() == 4
     });
@@ -210,7 +212,12 @@ fn test_file_set_len() {
 
     // Can't use set_len on a file not opened for writing
     let file = OpenOptions::new().read(true).open(&path).unwrap();
-    assert_eq!(ErrorKind::InvalidInput, file.set_len(14).unwrap_err().kind());
+    // Due to https://github.com/rust-lang/miri/issues/4457, we have to assume the failure could
+    // be either of the Windows or Unix kind, no matter which platform we're on.
+    assert!(
+        [ErrorKind::PermissionDenied, ErrorKind::InvalidInput]
+            .contains(&file.set_len(14).unwrap_err().kind())
+    );
 
     remove_file(&path).unwrap();
 }