terraform/internal/replacefile/replacefile_windows.go

41 lines
1.4 KiB
Go

// +build windows
package replacefile
import (
"os"
"syscall"
"golang.org/x/sys/windows"
)
// AtomicRename renames from the source path to the destination path,
// atomically replacing any file that might already exist at the destination.
//
// Typically this operation can succeed only if the source and destination
// are within the same physical filesystem, so this function is best reserved
// for cases where the source and destination exist in the same directory and
// only the local filename differs between them.
func AtomicRename(source, destination string) error {
// On Windows, renaming one file over another is not atomic and certain
// error conditions can result in having only the source file and nothing
// at the destination file. Instead, we need to call into the MoveFileEx
// Windows API function, setting two flags to opt in to replacing an
// existing file.
srcPtr, err := syscall.UTF16PtrFromString(source)
if err != nil {
return &os.LinkError{"replace", source, destination, err}
}
destPtr, err := syscall.UTF16PtrFromString(destination)
if err != nil {
return &os.LinkError{"replace", source, destination, err}
}
flags := uint32(windows.MOVEFILE_REPLACE_EXISTING | windows.MOVEFILE_WRITE_THROUGH)
err = windows.MoveFileEx(srcPtr, destPtr, flags)
if err != nil {
return &os.LinkError{"replace", source, destination, err}
}
return nil
}