GetDeviceLogicalBlockSize Windows impl

osspecifics/osspecifics.go

@@ -89,3 +89,23 @@ func CheckRunAsRoot() (bool, error) {
 
 	return currentUser.Username == "root", nil
 }
+
+func GetDeviceLogicalBlockSize(devPath string) (uint64, error) {
+	fd, err := os.Open(devPath)
+	if err != nil {
+		return 0, errors.Wrap(err, "open device")
+	}
+
+	defer func() { _ = fd.Close() }()
+
+	bs, err := getDeviceLogicalBlockSizeInner(fd.Fd())
+	if err != nil {
+		return 0, errors.Wrap(err, "get block size inner")
+	}
+
+	if bs <= 0 {
+		return 0, fmt.Errorf("retrieved block size is zero (or negative): '%v'", bs)
+	}
+
+	return uint64(bs), nil
+}

osspecifics/osspecifics_cross.go

@@ -1,44 +0,0 @@
-// Linsk - A utility to access Linux-native file systems on non-Linux operating systems.
-// Copyright (c) 2023 The Linsk Authors.
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program. If not, see <https://www.gnu.org/licenses/>.
-
-package osspecifics
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/pkg/errors"
-)
-
-func GetDeviceLogicalBlockSize(devPath string) (uint64, error) {
-	fd, err := os.Open(devPath)
-	if err != nil {
-		return 0, errors.Wrap(err, "open device")
-	}
-
-	defer func() { _ = fd.Close() }()
-
-	bs, err := getDeviceLogicalBlockSizeInner(fd.Fd())
-	if err != nil {
-		return 0, errors.Wrap(err, "get block size inner")
-	}
-
-	if bs <= 0 {
-		return 0, fmt.Errorf("retrieved block size is zero (or negative): '%v'", bs)
-	}
-
-	return uint64(bs), nil
-}

osspecifics/osspecifics_windows.go

@@ -19,6 +19,7 @@
 package osspecifics
 
 import (
+	"encoding/binary"
 	"fmt"
 	"os/exec"
 	"regexp"
@@ -99,3 +100,31 @@ func CheckRunAsRoot() (bool, error) {
 
 	return member, nil
 }
+
+func GetDeviceLogicalBlockSize(devPath string) (uint64, error) {
+	diskPath, err := windows.UTF16PtrFromString(devPath)
+	if err != nil {
+		return 0, errors.Wrap(err, "create utf-16 ptr from dev path string")
+	}
+
+	handle, err := windows.CreateFile(diskPath, syscall.GENERIC_READ, syscall.FILE_SHARE_READ, nil, syscall.OPEN_EXISTING, syscall.FILE_ATTRIBUTE_NORMAL, 0)
+	if err != nil {
+		return 0, errors.Wrap(err, "create windows file")
+	}
+
+	defer func() { _ = windows.CloseHandle(handle) }()
+
+	buf := make([]uint8, 128)
+	var read uint32
+	err = windows.DeviceIoControl(handle, 0x700a0, nil, 0, &buf[0], uint32(len(buf)), &read, nil) // IOCTL_DISK_GET_DRIVE_GEOMETRY_EX call.
+	if err != nil {
+		return 0, errors.Wrap(err, "invoke windows device i/o control")
+	}
+
+	// Skipping cylinders, media type, tracks per cylinder, and sectors per track fields in the disk geometry return struct.
+	//
+	// We could theoretically use `unsafe` type casting, but it's in the name - it's unsafe.
+	bs := binary.NativeEndian.Uint32(buf[20:24])
+
+	return uint64(bs), nil
+}