//go:build windows
// +build windows
package winio
import (
"os"
"runtime"
"unsafe"
"golang.org/x/sys/windows"
)
// FileBasicInfo contains file access time and file attributes information.
type FileBasicInfo struct {
CreationTime, LastAccessTime, LastWriteTime, ChangeTime windows.Filetime
FileAttributes uint32
_ uint32 // padding
}
// alignedFileBasicInfo is a FileBasicInfo, but aligned to uint64 by containing
// uint64 rather than windows.Filetime. Filetime contains two uint32s. uint64
// alignment is necessary to pass this as FILE_BASIC_INFO.
type alignedFileBasicInfo struct {
CreationTime, LastAccessTime, LastWriteTime, ChangeTime uint64
FileAttributes uint32
_ uint32 // padding
}
// GetFileBasicInfo retrieves times and attributes for a file.
func GetFileBasicInfo(f *os.File) (*FileBasicInfo, error) {
bi := &alignedFileBasicInfo{}
if err := windows.GetFileInformationByHandleEx(
windows.Handle(f.Fd()),
windows.FileBasicInfo,
(*byte)(unsafe.Pointer(bi)),
uint32(unsafe.Sizeof(*bi)),
); err != nil {
return nil, &os.PathError{Op: "GetFileInformationByHandleEx", Path: f.Name(), Err: err}
}
runtime.KeepAlive(f)
// Reinterpret the alignedFileBasicInfo as a FileBasicInfo so it matches the
// public API of this module. The data may be unnecessarily aligned.
return (*FileBasicInfo)(unsafe.Pointer(bi)), nil
}
// SetFileBasicInfo sets times and attributes for a file.
func SetFileBasicInfo(f *os.File, bi *FileBasicInfo) error {
// Create an alignedFileBasicInfo based on a FileBasicInfo. The copy is
// suitable to pass to GetFileInformationByHandleEx.
biAligned := *(*alignedFileBasicInfo)(unsafe.Pointer(bi))
if err := windows.SetFileInformationByHandle(
windows.Handle(f.Fd()),
windows.FileBasicInfo,
(*byte)(unsafe.Pointer(&biAligned)),
uint32(unsafe.Sizeof(biAligned)),
); err != nil {
return &os.PathError{Op: "SetFileInformationByHandle", Path: f.Name(), Err: err}
}
runtime.KeepAlive(f)
return nil
}
// FileStandardInfo contains extended information for the file.
// FILE_STANDARD_INFO in WinBase.h
// https://docs.microsoft.com/en-us/windows/win32/api/winbase/ns-winbase-file_standard_info
type FileStandardInfo struct {
AllocationSize, EndOfFile int64
NumberOfLinks uint32
DeletePending, Directory bool
}
// GetFileStandardInfo retrieves ended information for the file.
func GetFileStandardInfo(f *os.File) (*FileStandardInfo, error) {
si := &FileStandardInfo{}
if err := windows.GetFileInformationByHandleEx(windows.Handle(f.Fd()),
windows.FileStandardInfo,
(*byte)(unsafe.Pointer(si)),
uint32(unsafe.Sizeof(*si))); err != nil {
return nil, &os.PathError{Op: "GetFileInformationByHandleEx", Path: f.Name(), Err: err}
}
runtime.KeepAlive(f)
return si, nil
}
// FileIDInfo contains the volume serial number and file ID for a file. This pair should be
// unique on a system.
type FileIDInfo struct {
VolumeSerialNumber uint64
FileID [16]byte
}
// GetFileID retrieves the unique (volume, file ID) pair for a file.
func GetFileID(f *os.File) (*FileIDInfo, error) {
fileID := &FileIDInfo{}
if err := windows.GetFileInformationByHandleEx(
windows.Handle(f.Fd()),
windows.FileIdInfo,
(*byte)(unsafe.Pointer(fileID)),
uint32(unsafe.Sizeof(*fileID)),
); err != nil {
return nil, &os.PathError{Op: "GetFileInformationByHandleEx", Path: f.Name(), Err: err}
}
runtime.KeepAlive(f)
return fileID, nil
}