From f011a81ddc2c7a2ddd9cced41a5b3e3d75727271 Mon Sep 17 00:00:00 2001 From: John Starks Date: Thu, 18 Feb 2016 20:40:32 -0800 Subject: [PATCH] Add interface to BackupRead/BackupWrite --- backup.go | 241 ++++++++++++++++++++++++++++++++++++++++++++++ backup_test.go | 255 +++++++++++++++++++++++++++++++++++++++++++++++++ pipe.go | 2 +- reparse.go | 124 ++++++++++++++++++++++++ sd.go | 17 +++- syscall.go | 2 +- zsyscall.go | 71 ++++++++++++++ 7 files changed, 708 insertions(+), 4 deletions(-) create mode 100644 backup.go create mode 100644 backup_test.go create mode 100644 reparse.go diff --git a/backup.go b/backup.go new file mode 100644 index 0000000..bfefd42 --- /dev/null +++ b/backup.go @@ -0,0 +1,241 @@ +package winio + +import ( + "encoding/binary" + "errors" + "fmt" + "io" + "io/ioutil" + "os" + "runtime" + "syscall" + "unicode/utf16" +) + +//sys backupRead(h syscall.Handle, b []byte, bytesRead *uint32, abort bool, processSecurity bool, context *uintptr) (err error) = BackupRead +//sys backupWrite(h syscall.Handle, b []byte, bytesWritten *uint32, abort bool, processSecurity bool, context *uintptr) (err error) = BackupWrite + +const ( + BackupData = uint32(iota + 1) + BackupEaData + BackupSecurity + BackupAlternateData + BackupLink + BackupPropertyData + BackupObjectId + BackupReparseData + BackupSparseBlock + BackupTxfsData + + StreamSparseAttributes = uint32(8) +) + +// BackupHeader represents a backup stream of a file. +type BackupHeader struct { + Id uint32 // The backup stream ID + Attributes uint32 // Stream attributes + Size int64 // The size of the stream in bytes + Name string // The name of the stream (for BackupAlternateData only). + Offset int64 // The offset of the stream in the file (for BackupSparseBlock only). +} + +type win32StreamId struct { + StreamId uint32 + Attributes uint32 + Size uint64 + NameSize uint32 +} + +// BackupStreamReader reads from a stream produced by the BackupRead Win32 API and produces a series +// of BackupHeader values. +type BackupStreamReader struct { + r io.Reader + bytesLeft int64 +} + +// NewBackupStreamReader produces a BackupStreamReader from any io.Reader. +func NewBackupStreamReader(r io.Reader) *BackupStreamReader { + return &BackupStreamReader{r, 0} +} + +// Next returns the next backup stream and prepares for calls to Write(). It skips the remainder of the current stream if +// it was not completely read. +func (r *BackupStreamReader) Next() (*BackupHeader, error) { + if r.bytesLeft > 0 { + if _, err := io.Copy(ioutil.Discard, r); err != nil { + return nil, err + } + } + var wsi win32StreamId + if err := binary.Read(r.r, binary.LittleEndian, &wsi); err != nil { + return nil, err + } + hdr := &BackupHeader{ + Id: wsi.StreamId, + Attributes: wsi.Attributes, + Size: int64(wsi.Size), + } + if wsi.NameSize != 0 { + name := make([]uint16, int(wsi.NameSize/2)) + if err := binary.Read(r.r, binary.LittleEndian, name); err != nil { + return nil, err + } + hdr.Name = syscall.UTF16ToString(name) + } + if wsi.StreamId == BackupSparseBlock { + if err := binary.Read(r.r, binary.LittleEndian, &hdr.Offset); err != nil { + return nil, err + } + hdr.Size -= 8 + } + r.bytesLeft = hdr.Size + return hdr, nil +} + +// Read reads from the current backup stream. +func (r *BackupStreamReader) Read(b []byte) (int, error) { + if r.bytesLeft == 0 { + return 0, io.EOF + } + if int64(len(b)) > r.bytesLeft { + b = b[:r.bytesLeft] + } + n, err := r.r.Read(b) + r.bytesLeft -= int64(n) + if err == io.EOF { + err = io.ErrUnexpectedEOF + } else if r.bytesLeft == 0 && err == nil { + err = io.EOF + } + return n, err +} + +// BackupStreamWriter writes a stream compatible with the BackupWrite Win32 API. +type BackupStreamWriter struct { + w io.Writer + bytesLeft int64 +} + +// NewBackupStreamWriter produces a BackupStreamWriter on top of an io.Writer. +func NewBackupStreamWriter(w io.Writer) *BackupStreamWriter { + return &BackupStreamWriter{w, 0} +} + +// WriteHeader writes the next backup stream header and prepares for calls to Write(). +func (w *BackupStreamWriter) WriteHeader(hdr *BackupHeader) error { + if w.bytesLeft != 0 { + return fmt.Errorf("missing %d bytes", w.bytesLeft) + } + name := utf16.Encode([]rune(hdr.Name)) + wsi := win32StreamId{ + StreamId: hdr.Id, + Attributes: hdr.Attributes, + Size: uint64(hdr.Size), + NameSize: uint32(len(name) * 2), + } + if hdr.Id == BackupSparseBlock { + // Include space for the int64 block offset + wsi.Size += 8 + } + if err := binary.Write(w.w, binary.LittleEndian, &wsi); err != nil { + return err + } + if len(name) != 0 { + if err := binary.Write(w.w, binary.LittleEndian, name); err != nil { + return err + } + } + if hdr.Id == BackupSparseBlock { + if err := binary.Write(w.w, binary.LittleEndian, hdr.Offset); err != nil { + return err + } + } + w.bytesLeft = hdr.Size + return nil +} + +// Write writes to the current backup stream. +func (w *BackupStreamWriter) Write(b []byte) (int, error) { + if w.bytesLeft < int64(len(b)) { + return 0, fmt.Errorf("too many bytes by %d", int64(len(b))-w.bytesLeft) + } + n, err := w.w.Write(b) + w.bytesLeft -= int64(n) + return n, err +} + +// BackupFileReader provides an io.ReadCloser interface on top of the BackupRead Win32 API. +type BackupFileReader struct { + f *os.File + includeSecurity bool + ctx uintptr +} + +// NewBackupFileReader returns a new BackupFileReader from a file handle. If includeSecurity is true, +// Read will attempt to read the security descriptor of the file. +func NewBackupFileReader(f *os.File, includeSecurity bool) *BackupFileReader { + r := &BackupFileReader{f, includeSecurity, 0} + runtime.SetFinalizer(r, func(r *BackupFileReader) { r.Close() }) + return r +} + +// Read reads a backup stream from the file by calling the Win32 API BackupRead(). +func (r *BackupFileReader) Read(b []byte) (int, error) { + var bytesRead uint32 + err := backupRead(syscall.Handle(r.f.Fd()), b, &bytesRead, false, r.includeSecurity, &r.ctx) + if err != nil { + return 0, &os.PathError{"BackupRead", r.f.Name(), err} + } + if bytesRead == 0 { + return 0, io.EOF + } + return int(bytesRead), nil +} + +// Close frees Win32 resources associated with the BackupFileReader. It does not close +// the underlying file. +func (r *BackupFileReader) Close() error { + if r.ctx != 0 { + backupRead(syscall.Handle(r.f.Fd()), nil, nil, true, false, &r.ctx) + r.ctx = 0 + } + return nil +} + +// BackupFileWriter provides an io.WriteCloser interface on top of the BackupWrite Win32 API. +type BackupFileWriter struct { + f *os.File + includeSecurity bool + ctx uintptr +} + +// NewBackupFileWrtier returns a new BackupFileWriter from a file handle. If includeSecurity is true, +// Write() will attempt to restore the security descriptor from the stream. +func NewBackupFileWriter(f *os.File, includeSecurity bool) *BackupFileWriter { + w := &BackupFileWriter{f, includeSecurity, 0} + runtime.SetFinalizer(w, func(w *BackupFileWriter) { w.Close() }) + return w +} + +// Write restores a portion of the file using the provided backup stream. +func (w *BackupFileWriter) Write(b []byte) (int, error) { + var bytesWritten uint32 + err := backupWrite(syscall.Handle(w.f.Fd()), b, &bytesWritten, false, w.includeSecurity, &w.ctx) + if err != nil { + return 0, &os.PathError{"BackupWrite", w.f.Name(), err} + } + if int(bytesWritten) != len(b) { + return int(bytesWritten), errors.New("not all bytes could be written") + } + return len(b), nil +} + +// Close frees Win32 resources associated with the BackupFileWriter. It does not +// close the underlying file. +func (w *BackupFileWriter) Close() error { + if w.ctx != 0 { + backupWrite(syscall.Handle(w.f.Fd()), nil, nil, true, false, &w.ctx) + w.ctx = 0 + } + return nil +} diff --git a/backup_test.go b/backup_test.go new file mode 100644 index 0000000..cc5a0c5 --- /dev/null +++ b/backup_test.go @@ -0,0 +1,255 @@ +package winio + +import ( + "io" + "io/ioutil" + "os" + "syscall" + "testing" +) + +var testFileName string + +func TestMain(m *testing.M) { + f, err := ioutil.TempFile("", "tmp") + if err != nil { + panic(err) + } + testFileName = f.Name() + f.Close() + defer os.Remove(testFileName) + os.Exit(m.Run()) +} + +func makeTestFile(makeADS bool) error { + os.Remove(testFileName) + f, err := os.Create(testFileName) + if err != nil { + return err + } + defer f.Close() + _, err = f.Write([]byte("testing 1 2 3\n")) + if err != nil { + return err + } + if makeADS { + a, err := os.Create(testFileName + ":ads.txt") + if err != nil { + return err + } + defer a.Close() + _, err = a.Write([]byte("alternate data stream\n")) + if err != nil { + return err + } + } + return nil +} + +func TestBackupRead(t *testing.T) { + err := makeTestFile(true) + if err != nil { + t.Fatal(err) + } + + f, err := os.Open(testFileName) + if err != nil { + t.Fatal(err) + } + defer f.Close() + r := NewBackupFileReader(f, false) + defer r.Close() + b, err := ioutil.ReadAll(r) + if err != nil { + t.Fatal(err) + } + if len(b) == 0 { + t.Fatal("no data") + } +} + +func TestBackupStreamRead(t *testing.T) { + err := makeTestFile(true) + if err != nil { + t.Fatal(err) + } + + f, err := os.Open(testFileName) + if err != nil { + t.Fatal(err) + } + defer f.Close() + r := NewBackupFileReader(f, false) + defer r.Close() + + br := NewBackupStreamReader(r) + gotData := false + gotAltData := false + for { + hdr, err := br.Next() + if err == io.EOF { + break + } + if err != nil { + t.Fatal(err) + } + + switch hdr.Id { + case BackupData: + if gotData { + t.Fatal("duplicate data") + } + if hdr.Name != "" { + t.Fatalf("unexpected name %s", hdr.Name) + } + b, err := ioutil.ReadAll(br) + if err != nil { + t.Fatal(err) + } + if string(b) != "testing 1 2 3\n" { + t.Fatalf("incorrect data %v", b) + } + gotData = true + case BackupAlternateData: + if gotAltData { + t.Fatal("duplicate alt data") + } + if hdr.Name != ":ads.txt:$DATA" { + t.Fatalf("incorrect name %s", hdr.Name) + } + b, err := ioutil.ReadAll(br) + if err != nil { + t.Fatal(err) + } + if string(b) != "alternate data stream\n" { + t.Fatalf("incorrect data %v", b) + } + gotAltData = true + default: + t.Fatalf("unknown stream ID %d", hdr.Id) + } + } + if !gotData || !gotAltData { + t.Fatal("missing stream") + } +} + +func TestBackupStreamWrite(t *testing.T) { + f, err := os.Create(testFileName) + if err != nil { + t.Fatal(err) + } + defer f.Close() + w := NewBackupFileWriter(f, false) + defer w.Close() + + data := "testing 1 2 3\n" + altData := "alternate stream\n" + + br := NewBackupStreamWriter(w) + err = br.WriteHeader(&BackupHeader{Id: BackupData, Size: int64(len(data))}) + if err != nil { + t.Fatal(err) + } + n, err := br.Write([]byte(data)) + if err != nil { + t.Fatal(err) + } + if n != len(data) { + t.Fatal("short write") + } + + err = br.WriteHeader(&BackupHeader{Id: BackupAlternateData, Size: int64(len(altData)), Name: ":ads.txt:$DATA"}) + if err != nil { + t.Fatal(err) + } + n, err = br.Write([]byte(altData)) + if err != nil { + t.Fatal(err) + } + if n != len(altData) { + t.Fatal("short write") + } + + f.Close() + + b, err := ioutil.ReadFile(testFileName) + if err != nil { + t.Fatal(err) + } + if string(b) != data { + t.Fatalf("wrong data %v", b) + } + + b, err = ioutil.ReadFile(testFileName + ":ads.txt") + if err != nil { + t.Fatal(err) + } + if string(b) != altData { + t.Fatalf("wrong data %v", b) + } +} + +func makeSparseFile() error { + os.Remove(testFileName) + f, err := os.Create(testFileName) + if err != nil { + return err + } + defer f.Close() + + const ( + FSCTL_SET_SPARSE = 0x000900c4 + FSCTL_SET_ZERO_DATA = 0x000980c8 + ) + + err = syscall.DeviceIoControl(syscall.Handle(f.Fd()), FSCTL_SET_SPARSE, nil, 0, nil, 0, nil, nil) + if err != nil { + return err + } + + _, err = f.Write([]byte("testing 1 2 3\n")) + if err != nil { + return err + } + + _, err = f.Seek(1000000, 0) + if err != nil { + return err + } + + _, err = f.Write([]byte("more data later\n")) + if err != nil { + return err + } + + return nil +} + +func TestBackupSparseFile(t *testing.T) { + err := makeSparseFile() + if err != nil { + t.Fatal(err) + } + + f, err := os.Open(testFileName) + if err != nil { + t.Fatal(err) + } + defer f.Close() + r := NewBackupFileReader(f, false) + defer r.Close() + + br := NewBackupStreamReader(r) + for { + hdr, err := br.Next() + if err == io.EOF { + break + } + if err != nil { + t.Fatal(err) + } + + t.Log(hdr) + } +} diff --git a/pipe.go b/pipe.go index b281b5e..0e398ff 100644 --- a/pipe.go +++ b/pipe.go @@ -213,7 +213,7 @@ func ListenPipe(path, sddl string) (net.Listener, error) { err error ) if sddl != "" { - sd, err = sddlToSecurityDescriptor(sddl) + sd, err = SddlToSecurityDescriptor(sddl) if err != nil { return nil, err } diff --git a/reparse.go b/reparse.go new file mode 100644 index 0000000..96d7b9a --- /dev/null +++ b/reparse.go @@ -0,0 +1,124 @@ +package winio + +import ( + "bytes" + "encoding/binary" + "fmt" + "strings" + "unicode/utf16" + "unsafe" +) + +const ( + reparseTagMountPoint = 0xA0000003 + reparseTagSymlink = 0xA000000C +) + +type reparseDataBuffer struct { + ReparseTag uint32 + ReparseDataLength uint16 + Reserved uint16 + SubstituteNameOffset uint16 + SubstituteNameLength uint16 + PrintNameOffset uint16 + PrintNameLength uint16 +} + +// ReparsePoint describes a Win32 symlink or mount point. +type ReparsePoint struct { + Target string + IsMountPoint bool +} + +// UnsupportedReparsePointError is returned when trying to decode a non-symlink or +// mount point reparse point. +type UnsupportedReparsePointError struct { + Tag uint32 +} + +func (e *UnsupportedReparsePointError) Error() string { + return fmt.Sprintf("unsupported reparse point %x", e.Tag) +} + +// DecodeReparsePoint decodes a Win32 REPARSE_DATA_BUFFER structure containing either a symlink +// or a mount point. +func DecodeReparsePoint(b []byte) (*ReparsePoint, error) { + isMountPoint := false + tag := binary.LittleEndian.Uint32(b[0:4]) + switch tag { + case reparseTagMountPoint: + isMountPoint = true + case reparseTagSymlink: + default: + return nil, &UnsupportedReparsePointError{tag} + } + nameOffset := 16 + binary.LittleEndian.Uint16(b[12:14]) + if !isMountPoint { + nameOffset += 4 + } + nameLength := binary.LittleEndian.Uint16(b[14:16]) + name := make([]uint16, nameLength/2) + err := binary.Read(bytes.NewReader(b[nameOffset:nameOffset+nameLength]), binary.LittleEndian, &name) + if err != nil { + return nil, err + } + return &ReparsePoint{string(utf16.Decode(name)), isMountPoint}, nil +} + +func isDriveLetter(c byte) bool { + return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') +} + +// EncodeReparsePoint encodes a Win32 REPARSE_DATA_BUFFER structure describing a symlink or +// mount point. +func EncodeReparsePoint(rp *ReparsePoint) []byte { + // Generate an NT path and determine if this is a relative path. + var ntTarget string + relative := false + if strings.HasPrefix(rp.Target, `\\?\`) { + ntTarget = rp.Target + } else if strings.HasPrefix(rp.Target, `\\`) { + ntTarget = `\??\UNC\` + rp.Target[2:] + } else if len(rp.Target) >= 2 && isDriveLetter(rp.Target[0]) && rp.Target[1] == ':' { + ntTarget = `\??\` + rp.Target + } else { + ntTarget = rp.Target + relative = true + } + + // The paths must be NUL-terminated even though they are counted strings. + target16 := utf16.Encode([]rune(rp.Target + "\x00")) + ntTarget16 := utf16.Encode([]rune(ntTarget + "\x00")) + + size := int(unsafe.Sizeof(reparseDataBuffer{})) - 8 + size += len(ntTarget16)*2 + len(target16)*2 + + tag := uint32(reparseTagMountPoint) + if !rp.IsMountPoint { + tag = reparseTagSymlink + size += 4 // Add room for symlink flags + } + + data := reparseDataBuffer{ + ReparseTag: tag, + ReparseDataLength: uint16(size), + SubstituteNameOffset: 0, + SubstituteNameLength: uint16((len(ntTarget16) - 1) * 2), + PrintNameOffset: uint16(len(ntTarget16) * 2), + PrintNameLength: uint16((len(target16) - 1) * 2), + } + + var b bytes.Buffer + binary.Write(&b, binary.LittleEndian, &data) + if !rp.IsMountPoint { + flags := uint32(0) + if relative { + flags |= 1 + } + binary.Write(&b, binary.LittleEndian, flags) + } + + binary.Write(&b, binary.LittleEndian, ntTarget16) + binary.Write(&b, binary.LittleEndian, target16) + return b.Bytes() +} diff --git a/sd.go b/sd.go index 2df5a7c..60ab56c 100644 --- a/sd.go +++ b/sd.go @@ -8,6 +8,7 @@ import ( //sys lookupAccountName(systemName *uint16, accountName string, sid *byte, sidSize *uint32, refDomain *uint16, refDomainSize *uint32, sidNameUse *uint32) (err error) = advapi32.LookupAccountNameW //sys convertSidToStringSid(sid *byte, str **uint16) (err error) = advapi32.ConvertSidToStringSidW //sys convertStringSecurityDescriptorToSecurityDescriptor(str string, revision uint32, sd *uintptr, size *uint32) (err error) = advapi32.ConvertStringSecurityDescriptorToSecurityDescriptorW +//sys convertSecurityDescriptorToStringSecurityDescriptor(sd *byte, revision uint32, secInfo uint32, sddl **uint16, sddlSize *uint32) (err error) = advapi32.ConvertSecurityDescriptorToStringSecurityDescriptorW //sys localFree(mem uintptr) = LocalFree //sys getSecurityDescriptorLength(sd uintptr) (len uint32) = advapi32.GetSecurityDescriptorLength @@ -70,7 +71,7 @@ func LookupSidByName(name string) (sid string, err error) { return sid, nil } -func sddlToSecurityDescriptor(sddl string) ([]byte, error) { +func SddlToSecurityDescriptor(sddl string) ([]byte, error) { var sdBuffer uintptr err := convertStringSecurityDescriptorToSecurityDescriptor(sddl, 1, &sdBuffer, nil) if err != nil { @@ -78,6 +79,18 @@ func sddlToSecurityDescriptor(sddl string) ([]byte, error) { } defer localFree(sdBuffer) sd := make([]byte, getSecurityDescriptorLength(sdBuffer)) - copy(sd, (*[1 << 30]byte)(unsafe.Pointer(sdBuffer))[:len(sd)]) + copy(sd, (*[0xffff]byte)(unsafe.Pointer(sdBuffer))[:len(sd)]) return sd, nil } + +func SecurityDescriptorToSddl(sd []byte) (string, error) { + var sddl *uint16 + // The returned string length seems to including an aribtrary number of terminating NULs. + // Don't use it. + err := convertSecurityDescriptorToStringSecurityDescriptor(&sd[0], 1, 0xff, &sddl, nil) + if err != nil { + return "", err + } + defer localFree(uintptr(unsafe.Pointer(sddl))) + return syscall.UTF16ToString((*[0xffff]uint16)(unsafe.Pointer(sddl))[:]), nil +} diff --git a/syscall.go b/syscall.go index ab66ae2..96fdff7 100644 --- a/syscall.go +++ b/syscall.go @@ -1,3 +1,3 @@ package winio -//go:generate go run $GOROOT/src/syscall/mksyscall_windows.go -output zsyscall.go file.go pipe.go sd.go fileinfo.go privilege.go +//go:generate go run $GOROOT/src/syscall/mksyscall_windows.go -output zsyscall.go file.go pipe.go sd.go fileinfo.go privilege.go backup.go diff --git a/zsyscall.go b/zsyscall.go index f0a7419..19d53dc 100644 --- a/zsyscall.go +++ b/zsyscall.go @@ -22,6 +22,7 @@ var ( procLookupAccountNameW = modadvapi32.NewProc("LookupAccountNameW") procConvertSidToStringSidW = modadvapi32.NewProc("ConvertSidToStringSidW") procConvertStringSecurityDescriptorToSecurityDescriptorW = modadvapi32.NewProc("ConvertStringSecurityDescriptorToSecurityDescriptorW") + procConvertSecurityDescriptorToStringSecurityDescriptorW = modadvapi32.NewProc("ConvertSecurityDescriptorToStringSecurityDescriptorW") procLocalFree = modkernel32.NewProc("LocalFree") procGetSecurityDescriptorLength = modadvapi32.NewProc("GetSecurityDescriptorLength") procGetFileInformationByHandleEx = modkernel32.NewProc("GetFileInformationByHandleEx") @@ -34,6 +35,8 @@ var ( procLookupPrivilegeValueW = modadvapi32.NewProc("LookupPrivilegeValueW") procLookupPrivilegeNameW = modadvapi32.NewProc("LookupPrivilegeNameW") procLookupPrivilegeDisplayNameW = modadvapi32.NewProc("LookupPrivilegeDisplayNameW") + procBackupRead = modkernel32.NewProc("BackupRead") + procBackupWrite = modkernel32.NewProc("BackupWrite") ) func cancelIoEx(file syscall.Handle, o *syscall.Overlapped) (err error) { @@ -216,6 +219,18 @@ func _convertStringSecurityDescriptorToSecurityDescriptor(str *uint16, revision return } +func convertSecurityDescriptorToStringSecurityDescriptor(sd *byte, revision uint32, secInfo uint32, sddl **uint16, sddlSize *uint32) (err error) { + r1, _, e1 := syscall.Syscall6(procConvertSecurityDescriptorToStringSecurityDescriptorW.Addr(), 5, uintptr(unsafe.Pointer(sd)), uintptr(revision), uintptr(secInfo), uintptr(unsafe.Pointer(sddl)), uintptr(unsafe.Pointer(sddlSize)), 0) + if r1 == 0 { + if e1 != 0 { + err = error(e1) + } else { + err = syscall.EINVAL + } + } + return +} + func localFree(mem uintptr) { syscall.Syscall(procLocalFree.Addr(), 1, uintptr(mem), 0, 0) return @@ -384,3 +399,59 @@ func _lookupPrivilegeDisplayName(systemName *uint16, name *uint16, buffer *uint1 } return } + +func backupRead(h syscall.Handle, b []byte, bytesRead *uint32, abort bool, processSecurity bool, context *uintptr) (err error) { + var _p0 *byte + if len(b) > 0 { + _p0 = &b[0] + } + var _p1 uint32 + if abort { + _p1 = 1 + } else { + _p1 = 0 + } + var _p2 uint32 + if processSecurity { + _p2 = 1 + } else { + _p2 = 0 + } + r1, _, e1 := syscall.Syscall9(procBackupRead.Addr(), 7, uintptr(h), uintptr(unsafe.Pointer(_p0)), uintptr(len(b)), uintptr(unsafe.Pointer(bytesRead)), uintptr(_p1), uintptr(_p2), uintptr(unsafe.Pointer(context)), 0, 0) + if r1 == 0 { + if e1 != 0 { + err = error(e1) + } else { + err = syscall.EINVAL + } + } + return +} + +func backupWrite(h syscall.Handle, b []byte, bytesWritten *uint32, abort bool, processSecurity bool, context *uintptr) (err error) { + var _p0 *byte + if len(b) > 0 { + _p0 = &b[0] + } + var _p1 uint32 + if abort { + _p1 = 1 + } else { + _p1 = 0 + } + var _p2 uint32 + if processSecurity { + _p2 = 1 + } else { + _p2 = 0 + } + r1, _, e1 := syscall.Syscall9(procBackupWrite.Addr(), 7, uintptr(h), uintptr(unsafe.Pointer(_p0)), uintptr(len(b)), uintptr(unsafe.Pointer(bytesWritten)), uintptr(_p1), uintptr(_p2), uintptr(unsafe.Pointer(context)), 0, 0) + if r1 == 0 { + if e1 != 0 { + err = error(e1) + } else { + err = syscall.EINVAL + } + } + return +}