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// Copyright 2015 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package zip
import (
"bytes"
"compress/flate"
"errors"
"fmt"
"hash/crc32"
"io"
"io/ioutil"
"os"
"path/filepath"
"sort"
"strings"
"sync"
"syscall"
"time"
"unicode"
"github.com/google/blueprint/pathtools"
"android/soong/jar"
"android/soong/third_party/zip"
)
// Block size used during parallel compression of a single file.
const parallelBlockSize = 1 * 1024 * 1024 // 1MB
// Minimum file size to use parallel compression. It requires more
// flate.Writer allocations, since we can't change the dictionary
// during Reset
const minParallelFileSize = parallelBlockSize * 6
// Size of the ZIP compression window (32KB)
const windowSize = 32 * 1024
type nopCloser struct {
io.Writer
}
func (nopCloser) Close() error {
return nil
}
type byteReaderCloser struct {
*bytes.Reader
io.Closer
}
type pathMapping struct {
dest, src string
zipMethod uint16
}
type FileArg struct {
PathPrefixInZip, SourcePrefixToStrip string
SourceFiles []string
JunkPaths bool
GlobDir string
}
type FileArgsBuilder struct {
state FileArg
err error
fs pathtools.FileSystem
fileArgs []FileArg
}
func NewFileArgsBuilder() *FileArgsBuilder {
return &FileArgsBuilder{
fs: pathtools.OsFs,
}
}
func (b *FileArgsBuilder) JunkPaths(v bool) *FileArgsBuilder {
b.state.JunkPaths = v
b.state.SourcePrefixToStrip = ""
return b
}
func (b *FileArgsBuilder) SourcePrefixToStrip(prefixToStrip string) *FileArgsBuilder {
b.state.JunkPaths = false
b.state.SourcePrefixToStrip = prefixToStrip
return b
}
func (b *FileArgsBuilder) PathPrefixInZip(rootPrefix string) *FileArgsBuilder {
b.state.PathPrefixInZip = rootPrefix
return b
}
func (b *FileArgsBuilder) File(name string) *FileArgsBuilder {
if b.err != nil {
return b
}
arg := b.state
arg.SourceFiles = []string{name}
b.fileArgs = append(b.fileArgs, arg)
return b
}
func (b *FileArgsBuilder) Dir(name string) *FileArgsBuilder {
if b.err != nil {
return b
}
arg := b.state
arg.GlobDir = name
b.fileArgs = append(b.fileArgs, arg)
return b
}
func (b *FileArgsBuilder) List(name string) *FileArgsBuilder {
if b.err != nil {
return b
}
f, err := b.fs.Open(name)
if err != nil {
b.err = err
return b
}
defer f.Close()
list, err := ioutil.ReadAll(f)
if err != nil {
b.err = err
return b
}
arg := b.state
arg.SourceFiles = strings.Fields(string(list))
b.fileArgs = append(b.fileArgs, arg)
return b
}
func (b *FileArgsBuilder) RspFile(name string) *FileArgsBuilder {
if b.err != nil {
return b
}
f, err := b.fs.Open(name)
if err != nil {
b.err = err
return b
}
defer f.Close()
list, err := ioutil.ReadAll(f)
if err != nil {
b.err = err
return b
}
arg := b.state
arg.SourceFiles = ReadRespFile(list)
b.fileArgs = append(b.fileArgs, arg)
return b
}
func (b *FileArgsBuilder) Error() error {
if b == nil {
return nil
}
return b.err
}
func (b *FileArgsBuilder) FileArgs() []FileArg {
if b == nil {
return nil
}
return b.fileArgs
}
type IncorrectRelativeRootError struct {
RelativeRoot string
Path string
}
func (x IncorrectRelativeRootError) Error() string {
return fmt.Sprintf("path %q is outside relative root %q", x.Path, x.RelativeRoot)
}
type ZipWriter struct {
time time.Time
createdFiles map[string]string
createdDirs map[string]string
directories bool
errors chan error
writeOps chan chan *zipEntry
cpuRateLimiter *CPURateLimiter
memoryRateLimiter *MemoryRateLimiter
compressorPool sync.Pool
compLevel int
followSymlinks pathtools.ShouldFollowSymlinks
ignoreMissingFiles bool
stderr io.Writer
fs pathtools.FileSystem
}
type zipEntry struct {
fh *zip.FileHeader
// List of delayed io.Reader
futureReaders chan chan io.Reader
// Only used for passing into the MemoryRateLimiter to ensure we
// release as much memory as much as we request
allocatedSize int64
}
type ZipArgs struct {
FileArgs []FileArg
OutputFilePath string
EmulateJar bool
SrcJar bool
AddDirectoryEntriesToZip bool
CompressionLevel int
ManifestSourcePath string
NumParallelJobs int
NonDeflatedFiles map[string]bool
WriteIfChanged bool
StoreSymlinks bool
IgnoreMissingFiles bool
Stderr io.Writer
Filesystem pathtools.FileSystem
}
const NOQUOTE = '\x00'
func ReadRespFile(bytes []byte) []string {
var args []string
var arg []rune
isEscaping := false
quotingStart := NOQUOTE
for _, c := range string(bytes) {
switch {
case isEscaping:
if quotingStart == '"' {
if !(c == '"' || c == '\\') {
// '\"' or '\\' will be escaped under double quoting.
arg = append(arg, '\\')
}
}
arg = append(arg, c)
isEscaping = false
case c == '\\' && quotingStart != '\'':
isEscaping = true
case quotingStart == NOQUOTE && (c == '\'' || c == '"'):
quotingStart = c
case quotingStart != NOQUOTE && c == quotingStart:
quotingStart = NOQUOTE
case quotingStart == NOQUOTE && unicode.IsSpace(c):
// Current character is a space outside quotes
if len(arg) != 0 {
args = append(args, string(arg))
}
arg = arg[:0]
default:
arg = append(arg, c)
}
}
if len(arg) != 0 {
args = append(args, string(arg))
}
return args
}
func ZipTo(args ZipArgs, w io.Writer) error {
if args.EmulateJar {
args.AddDirectoryEntriesToZip = true
}
// Have Glob follow symlinks if they are not being stored as symlinks in the zip file.
followSymlinks := pathtools.ShouldFollowSymlinks(!args.StoreSymlinks)
z := &ZipWriter{
time: jar.DefaultTime,
createdDirs: make(map[string]string),
createdFiles: make(map[string]string),
directories: args.AddDirectoryEntriesToZip,
compLevel: args.CompressionLevel,
followSymlinks: followSymlinks,
ignoreMissingFiles: args.IgnoreMissingFiles,
stderr: args.Stderr,
fs: args.Filesystem,
}
if z.fs == nil {
z.fs = pathtools.OsFs
}
if z.stderr == nil {
z.stderr = os.Stderr
}
pathMappings := []pathMapping{}
noCompression := args.CompressionLevel == 0
for _, fa := range args.FileArgs {
var srcs []string
for _, s := range fa.SourceFiles {
s = strings.TrimSpace(s)
if s == "" {
continue
}
globbed, _, err := z.fs.Glob(s, nil, followSymlinks)
if err != nil {
return err
}
if len(globbed) == 0 {
err := &os.PathError{
Op: "lstat",
Path: s,
Err: os.ErrNotExist,
}
if args.IgnoreMissingFiles {
fmt.Fprintln(z.stderr, "warning:", err)
} else {
return err
}
}
srcs = append(srcs, globbed...)
}
if fa.GlobDir != "" {
if exists, isDir, err := z.fs.Exists(fa.GlobDir); err != nil {
return err
} else if !exists && !args.IgnoreMissingFiles {
err := &os.PathError{
Op: "lstat",
Path: fa.GlobDir,
Err: os.ErrNotExist,
}
if args.IgnoreMissingFiles {
fmt.Fprintln(z.stderr, "warning:", err)
} else {
return err
}
} else if !isDir && !args.IgnoreMissingFiles {
err := &os.PathError{
Op: "lstat",
Path: fa.GlobDir,
Err: syscall.ENOTDIR,
}
if args.IgnoreMissingFiles {
fmt.Fprintln(z.stderr, "warning:", err)
} else {
return err
}
}
globbed, _, err := z.fs.Glob(filepath.Join(fa.GlobDir, "**/*"), nil, followSymlinks)
if err != nil {
return err
}
srcs = append(srcs, globbed...)
}
for _, src := range srcs {
err := fillPathPairs(fa, src, &pathMappings, args.NonDeflatedFiles, noCompression)
if err != nil {
return err
}
}
}
return z.write(w, pathMappings, args.ManifestSourcePath, args.EmulateJar, args.SrcJar, args.NumParallelJobs)
}
func Zip(args ZipArgs) error {
if args.OutputFilePath == "" {
return fmt.Errorf("output file path must be nonempty")
}
buf := &bytes.Buffer{}
var out io.Writer = buf
if !args.WriteIfChanged {
f, err := os.Create(args.OutputFilePath)
if err != nil {
return err
}
defer f.Close()
defer func() {
if err != nil {
os.Remove(args.OutputFilePath)
}
}()
out = f
}
err := ZipTo(args, out)
if err != nil {
return err
}
if args.WriteIfChanged {
err := pathtools.WriteFileIfChanged(args.OutputFilePath, buf.Bytes(), 0666)
if err != nil {
return err
}
}
return nil
}
func fillPathPairs(fa FileArg, src string, pathMappings *[]pathMapping,
nonDeflatedFiles map[string]bool, noCompression bool) error {
var dest string
if fa.JunkPaths {
dest = filepath.Base(src)
} else {
var err error
dest, err = filepath.Rel(fa.SourcePrefixToStrip, src)
if err != nil {
return err
}
if strings.HasPrefix(dest, "../") {
return IncorrectRelativeRootError{
Path: src,
RelativeRoot: fa.SourcePrefixToStrip,
}
}
}
dest = filepath.Join(fa.PathPrefixInZip, dest)
zipMethod := zip.Deflate
if _, found := nonDeflatedFiles[dest]; found || noCompression {
zipMethod = zip.Store
}
*pathMappings = append(*pathMappings,
pathMapping{dest: dest, src: src, zipMethod: zipMethod})
return nil
}
func jarSort(mappings []pathMapping) {
less := func(i int, j int) (smaller bool) {
return jar.EntryNamesLess(mappings[i].dest, mappings[j].dest)
}
sort.SliceStable(mappings, less)
}
func (z *ZipWriter) write(f io.Writer, pathMappings []pathMapping, manifest string, emulateJar, srcJar bool,
parallelJobs int) error {
z.errors = make(chan error)
defer close(z.errors)
// This channel size can be essentially unlimited -- it's used as a fifo
// queue decouple the CPU and IO loads. Directories don't require any
// compression time, but still cost some IO. Similar with small files that
// can be very fast to compress. Some files that are more difficult to
// compress won't take a corresponding longer time writing out.
//
// The optimum size here depends on your CPU and IO characteristics, and
// the the layout of your zip file. 1000 was chosen mostly at random as
// something that worked reasonably well for a test file.
//
// The RateLimit object will put the upper bounds on the number of
// parallel compressions and outstanding buffers.
z.writeOps = make(chan chan *zipEntry, 1000)
z.cpuRateLimiter = NewCPURateLimiter(int64(parallelJobs))
z.memoryRateLimiter = NewMemoryRateLimiter(0)
defer func() {
z.cpuRateLimiter.Stop()
z.memoryRateLimiter.Stop()
}()
if manifest != "" && !emulateJar {
return errors.New("must specify --jar when specifying a manifest via -m")
}
if emulateJar {
// manifest may be empty, in which case addManifest will fill in a default
pathMappings = append(pathMappings, pathMapping{jar.ManifestFile, manifest, zip.Deflate})
jarSort(pathMappings)
}
go func() {
var err error
defer close(z.writeOps)
for _, ele := range pathMappings {
if emulateJar && ele.dest == jar.ManifestFile {
err = z.addManifest(ele.dest, ele.src, ele.zipMethod)
} else {
err = z.addFile(ele.dest, ele.src, ele.zipMethod, emulateJar, srcJar)
}
if err != nil {
z.errors <- err
return
}
}
}()
zipw := zip.NewWriter(f)
var currentWriteOpChan chan *zipEntry
var currentWriter io.WriteCloser
var currentReaders chan chan io.Reader
var currentReader chan io.Reader
var done bool
for !done {
var writeOpsChan chan chan *zipEntry
var writeOpChan chan *zipEntry
var readersChan chan chan io.Reader
if currentReader != nil {
// Only read and process errors
} else if currentReaders != nil {
readersChan = currentReaders
} else if currentWriteOpChan != nil {
writeOpChan = currentWriteOpChan
} else {
writeOpsChan = z.writeOps
}
select {
case writeOp, ok := <-writeOpsChan:
if !ok {
done = true
}
currentWriteOpChan = writeOp
case op := <-writeOpChan:
currentWriteOpChan = nil
var err error
if op.fh.Method == zip.Deflate {
currentWriter, err = zipw.CreateCompressedHeader(op.fh)
} else {
var zw io.Writer
op.fh.CompressedSize64 = op.fh.UncompressedSize64
zw, err = zipw.CreateHeaderAndroid(op.fh)
currentWriter = nopCloser{zw}
}
if err != nil {
return err
}
currentReaders = op.futureReaders
if op.futureReaders == nil {
currentWriter.Close()
currentWriter = nil
}
z.memoryRateLimiter.Finish(op.allocatedSize)
case futureReader, ok := <-readersChan:
if !ok {
// Done with reading
currentWriter.Close()
currentWriter = nil
currentReaders = nil
}
currentReader = futureReader
case reader := <-currentReader:
_, err := io.Copy(currentWriter, reader)
if err != nil {
return err
}
currentReader = nil
case err := <-z.errors:
return err
}
}
// One last chance to catch an error
select {
case err := <-z.errors:
return err
default:
zipw.Close()
return nil
}
}
// imports (possibly with compression) <src> into the zip at sub-path <dest>
func (z *ZipWriter) addFile(dest, src string, method uint16, emulateJar, srcJar bool) error {
var fileSize int64
var executable bool
var s os.FileInfo
var err error
if z.followSymlinks {
s, err = z.fs.Stat(src)
} else {
s, err = z.fs.Lstat(src)
}
if err != nil {
if os.IsNotExist(err) && z.ignoreMissingFiles {
fmt.Fprintln(z.stderr, "warning:", err)
return nil
}
return err
}
createParentDirs := func(dest, src string) error {
if err := z.writeDirectory(filepath.Dir(dest), src, emulateJar); err != nil {
return err
}
if prev, exists := z.createdDirs[dest]; exists {
return fmt.Errorf("destination %q is both a directory %q and a file %q", dest, prev, src)
}
if prev, exists := z.createdFiles[dest]; exists {
return fmt.Errorf("destination %q has two files %q and %q", dest, prev, src)
}
z.createdFiles[dest] = src
return nil
}
if s.IsDir() {
if z.directories {
return z.writeDirectory(dest, src, emulateJar)
}
return nil
} else if s.Mode()&os.ModeSymlink != 0 {
err = createParentDirs(dest, src)
if err != nil {
return err
}
return z.writeSymlink(dest, src)
} else if s.Mode().IsRegular() {
r, err := z.fs.Open(src)
if err != nil {
return err
}
if srcJar && filepath.Ext(src) == ".java" {
// rewrite the destination using the package path if it can be determined
pkg, err := jar.JavaPackage(r, src)
if err != nil {
// ignore errors for now, leaving the file at in its original location in the zip
} else {
dest = filepath.Join(filepath.Join(strings.Split(pkg, ".")...), filepath.Base(src))
}
_, err = r.Seek(0, io.SeekStart)
if err != nil {
return err
}
}
fileSize = s.Size()
executable = s.Mode()&0100 != 0
header := &zip.FileHeader{
Name: dest,
Method: method,
UncompressedSize64: uint64(fileSize),
}
if executable {
header.SetMode(0700)
}
err = createParentDirs(dest, src)
if err != nil {
return err
}
return z.writeFileContents(header, r)
} else {
return fmt.Errorf("%s is not a file, directory, or symlink", src)
}
}
func (z *ZipWriter) addManifest(dest string, src string, method uint16) error {
if prev, exists := z.createdDirs[dest]; exists {
return fmt.Errorf("destination %q is both a directory %q and a file %q", dest, prev, src)
}
if prev, exists := z.createdFiles[dest]; exists {
return fmt.Errorf("destination %q has two files %q and %q", dest, prev, src)
}
if err := z.writeDirectory(filepath.Dir(dest), src, true); err != nil {
return err
}
var contents []byte
if src != "" {
f, err := z.fs.Open(src)
if err != nil {
return err
}
contents, err = ioutil.ReadAll(f)
f.Close()
if err != nil {
return err
}
}
fh, buf, err := jar.ManifestFileContents(contents)
if err != nil {
return err
}
reader := &byteReaderCloser{bytes.NewReader(buf), ioutil.NopCloser(nil)}
return z.writeFileContents(fh, reader)
}
func (z *ZipWriter) writeFileContents(header *zip.FileHeader, r pathtools.ReaderAtSeekerCloser) (err error) {
header.SetModTime(z.time)
compressChan := make(chan *zipEntry, 1)
z.writeOps <- compressChan
// Pre-fill a zipEntry, it will be sent in the compressChan once
// we're sure about the Method and CRC.
ze := &zipEntry{
fh: header,
}
ze.allocatedSize = int64(header.UncompressedSize64)
z.cpuRateLimiter.Request()
z.memoryRateLimiter.Request(ze.allocatedSize)
fileSize := int64(header.UncompressedSize64)
if fileSize == 0 {
fileSize = int64(header.UncompressedSize)
}
if header.Method == zip.Deflate && fileSize >= minParallelFileSize {
wg := new(sync.WaitGroup)
// Allocate enough buffer to hold all readers. We'll limit
// this based on actual buffer sizes in RateLimit.
ze.futureReaders = make(chan chan io.Reader, (fileSize/parallelBlockSize)+1)
// Calculate the CRC in the background, since reading the entire
// file could take a while.
//
// We could split this up into chunks as well, but it's faster
// than the compression. Due to the Go Zip API, we also need to
// know the result before we can begin writing the compressed
// data out to the zipfile.
wg.Add(1)
go z.crcFile(r, ze, compressChan, wg)
for start := int64(0); start < fileSize; start += parallelBlockSize {
sr := io.NewSectionReader(r, start, parallelBlockSize)
resultChan := make(chan io.Reader, 1)
ze.futureReaders <- resultChan
z.cpuRateLimiter.Request()
last := !(start+parallelBlockSize < fileSize)
var dict []byte
if start >= windowSize {
dict, err = ioutil.ReadAll(io.NewSectionReader(r, start-windowSize, windowSize))
if err != nil {
return err
}
}
wg.Add(1)
go z.compressPartialFile(sr, dict, last, resultChan, wg)
}
close(ze.futureReaders)
// Close the file handle after all readers are done
go func(wg *sync.WaitGroup, closer io.Closer) {
wg.Wait()
closer.Close()
}(wg, r)
} else {
go func() {
z.compressWholeFile(ze, r, compressChan)
r.Close()
}()
}
return nil
}
func (z *ZipWriter) crcFile(r io.Reader, ze *zipEntry, resultChan chan *zipEntry, wg *sync.WaitGroup) {
defer wg.Done()
defer z.cpuRateLimiter.Finish()
crc := crc32.NewIEEE()
_, err := io.Copy(crc, r)
if err != nil {
z.errors <- err
return
}
ze.fh.CRC32 = crc.Sum32()
resultChan <- ze
close(resultChan)
}
func (z *ZipWriter) compressPartialFile(r io.Reader, dict []byte, last bool, resultChan chan io.Reader, wg *sync.WaitGroup) {
defer wg.Done()
result, err := z.compressBlock(r, dict, last)
if err != nil {
z.errors <- err
return
}
z.cpuRateLimiter.Finish()
resultChan <- result
}
func (z *ZipWriter) compressBlock(r io.Reader, dict []byte, last bool) (*bytes.Buffer, error) {
buf := new(bytes.Buffer)
var fw *flate.Writer
var err error
if len(dict) > 0 {
// There's no way to Reset a Writer with a new dictionary, so
// don't use the Pool
fw, err = flate.NewWriterDict(buf, z.compLevel, dict)
} else {
var ok bool
if fw, ok = z.compressorPool.Get().(*flate.Writer); ok {
fw.Reset(buf)
} else {
fw, err = flate.NewWriter(buf, z.compLevel)
}
defer z.compressorPool.Put(fw)
}
if err != nil {
return nil, err
}
_, err = io.Copy(fw, r)
if err != nil {
return nil, err
}
if last {
fw.Close()
} else {
fw.Flush()
}
return buf, nil
}
func (z *ZipWriter) compressWholeFile(ze *zipEntry, r io.ReadSeeker, compressChan chan *zipEntry) {
crc := crc32.NewIEEE()
_, err := io.Copy(crc, r)
if err != nil {
z.errors <- err
return
}
ze.fh.CRC32 = crc.Sum32()
_, err = r.Seek(0, 0)
if err != nil {
z.errors <- err
return
}
readFile := func(reader io.ReadSeeker) ([]byte, error) {
_, err := reader.Seek(0, 0)
if err != nil {
return nil, err
}
buf, err := ioutil.ReadAll(reader)
if err != nil {
return nil, err
}
return buf, nil
}
ze.futureReaders = make(chan chan io.Reader, 1)
futureReader := make(chan io.Reader, 1)
ze.futureReaders <- futureReader
close(ze.futureReaders)
if ze.fh.Method == zip.Deflate {
compressed, err := z.compressBlock(r, nil, true)
if err != nil {
z.errors <- err
return
}
if uint64(compressed.Len()) < ze.fh.UncompressedSize64 {
futureReader <- compressed
} else {
buf, err := readFile(r)
if err != nil {
z.errors <- err
return
}
ze.fh.Method = zip.Store
futureReader <- bytes.NewReader(buf)
}
} else {
buf, err := readFile(r)
if err != nil {
z.errors <- err
return
}
ze.fh.Method = zip.Store
futureReader <- bytes.NewReader(buf)
}
z.cpuRateLimiter.Finish()
close(futureReader)
compressChan <- ze
close(compressChan)
}
// writeDirectory annotates that dir is a directory created for the src file or directory, and adds
// the directory entry to the zip file if directories are enabled.
func (z *ZipWriter) writeDirectory(dir string, src string, emulateJar bool) error {
// clean the input
dir = filepath.Clean(dir)
// discover any uncreated directories in the path
zipDirs := []string{}
for dir != "" && dir != "." {
if _, exists := z.createdDirs[dir]; exists {
break
}
if prev, exists := z.createdFiles[dir]; exists {
return fmt.Errorf("destination %q is both a directory %q and a file %q", dir, src, prev)
}
z.createdDirs[dir] = src
// parent directories precede their children
zipDirs = append([]string{dir}, zipDirs...)
dir = filepath.Dir(dir)
}
if z.directories {
// make a directory entry for each uncreated directory
for _, cleanDir := range zipDirs {
var dirHeader *zip.FileHeader
if emulateJar && cleanDir+"/" == jar.MetaDir {
dirHeader = jar.MetaDirFileHeader()
} else {
dirHeader = &zip.FileHeader{
Name: cleanDir + "/",
}
dirHeader.SetMode(0700 | os.ModeDir)
}
dirHeader.SetModTime(z.time)
ze := make(chan *zipEntry, 1)
ze <- &zipEntry{
fh: dirHeader,
}
close(ze)
z.writeOps <- ze
}
}
return nil
}
func (z *ZipWriter) writeSymlink(rel, file string) error {
fileHeader := &zip.FileHeader{
Name: rel,
}
fileHeader.SetModTime(z.time)
fileHeader.SetMode(0777 | os.ModeSymlink)
dest, err := z.fs.Readlink(file)
if err != nil {
return err
}
fileHeader.UncompressedSize64 = uint64(len(dest))
fileHeader.CRC32 = crc32.ChecksumIEEE([]byte(dest))
ze := make(chan *zipEntry, 1)
futureReaders := make(chan chan io.Reader, 1)
futureReader := make(chan io.Reader, 1)
futureReaders <- futureReader
close(futureReaders)
futureReader <- bytes.NewBufferString(dest)
close(futureReader)
ze <- &zipEntry{
fh: fileHeader,
futureReaders: futureReaders,
}
close(ze)
z.writeOps <- ze
return nil
}