restic/internal/restorer/restorer_windows_test.go

//go:build windows
// +build windows

package restorer

import (
	"math"
	"syscall"
	"testing"
	"unsafe"

	rtest "github.com/restic/restic/internal/test"
	"golang.org/x/sys/windows"
)

func getBlockCount(t *testing.T, filename string) int64 {
	libkernel32 := windows.NewLazySystemDLL("kernel32.dll")
	err := libkernel32.Load()
	rtest.OK(t, err)
	proc := libkernel32.NewProc("GetCompressedFileSizeW")
	err = proc.Find()
	rtest.OK(t, err)

	namePtr, err := syscall.UTF16PtrFromString(filename)
	rtest.OK(t, err)

	result, _, _ := proc.Call(uintptr(unsafe.Pointer(namePtr)), 0)

	const invalidFileSize = uintptr(4294967295)
	if result == invalidFileSize {
		return -1
	}

	return int64(math.Ceil(float64(result) / 512))
}