path: root/vendor/github.com/syndtr/goleveldb/leveldb/storage/file_storage_windows.go

// Copyright (c) 2013, Suryandaru Triandana <syndtr@gmail.com>
// All rights reserved.
//
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package storage

import (
    "syscall"
    "unsafe"
)

var (
    modkernel32 = syscall.NewLazyDLL("kernel32.dll")

    procMoveFileExW = modkernel32.NewProc("MoveFileExW")
)

const (
    _MOVEFILE_REPLACE_EXISTING = 1
)

type windowsFileLock struct {
    fd syscall.Handle
}

func (fl *windowsFileLock) release() error {
    return syscall.Close(fl.fd)
}

func newFileLock(path string, readOnly bool) (fl fileLock, err error) {
    pathp, err := syscall.UTF16PtrFromString(path)
    if err != nil {
        return
    }
    var access, shareMode uint32
    if readOnly {
        access = syscall.GENERIC_READ
        shareMode = syscall.FILE_SHARE_READ
    } else {
        access = syscall.GENERIC_READ | syscall.GENERIC_WRITE
    }
    fd, err := syscall.CreateFile(pathp, access, shareMode, nil, syscall.OPEN_EXISTING, syscall.FILE_ATTRIBUTE_NORMAL, 0)
    if err == syscall.ERROR_FILE_NOT_FOUND {
        fd, err = syscall.CreateFile(pathp, access, shareMode, nil, syscall.OPEN_ALWAYS, syscall.FILE_ATTRIBUTE_NORMAL, 0)
    }
    if err != nil {
        return
    }
    fl = &windowsFileLock{fd: fd}
    return
}

func moveFileEx(from *uint16, to *uint16, flags uint32) error {
    r1, _, e1 := syscall.Syscall(procMoveFileExW.Addr(), 3, uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(to)), uintptr(flags))
    if r1 == 0 {
        if e1 != 0 {
            return error(e1)
        }
        return syscall.EINVAL
    }
    return nil
}

func rename(oldpath, newpath string) error {
    from, err := syscall.UTF16PtrFromString(oldpath)
    if err != nil {
        return err
    }
    to, err := syscall.UTF16PtrFromString(newpath)
    if err != nil {
        return err
    }
    return moveFileEx(from, to, _MOVEFILE_REPLACE_EXISTING)
}

func syncDir(name string) error { return nil }