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authorDaniel J Walsh <dwalsh@redhat.com>2018-07-08 07:55:30 -0400
committerAtomic Bot <atomic-devel@projectatomic.io>2018-07-19 18:43:32 +0000
commit98703eb204923f06555605c648fc165a55214520 (patch)
treea407bae8b3489d4f9b0f0d0f228658bbfe95a38e /vendor/github.com/ulikunitz/xz/writer.go
parentc020db8cd21cb221cfbe36b264e0ec02999596ed (diff)
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Vendor in latest code for storage,image, buildah
vendor in containers/storage vendor in containers/image vendor in projectatomic/buildah Signed-off-by: Daniel J Walsh <dwalsh@redhat.com> Closes: #1114 Approved by: mheon
Diffstat (limited to 'vendor/github.com/ulikunitz/xz/writer.go')
-rw-r--r--vendor/github.com/ulikunitz/xz/writer.go386
1 files changed, 386 insertions, 0 deletions
diff --git a/vendor/github.com/ulikunitz/xz/writer.go b/vendor/github.com/ulikunitz/xz/writer.go
new file mode 100644
index 000000000..c126f7099
--- /dev/null
+++ b/vendor/github.com/ulikunitz/xz/writer.go
@@ -0,0 +1,386 @@
+// Copyright 2014-2017 Ulrich Kunitz. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package xz
+
+import (
+ "errors"
+ "hash"
+ "io"
+
+ "github.com/ulikunitz/xz/lzma"
+)
+
+// WriterConfig describe the parameters for an xz writer.
+type WriterConfig struct {
+ Properties *lzma.Properties
+ DictCap int
+ BufSize int
+ BlockSize int64
+ // checksum method: CRC32, CRC64 or SHA256
+ CheckSum byte
+ // match algorithm
+ Matcher lzma.MatchAlgorithm
+}
+
+// fill replaces zero values with default values.
+func (c *WriterConfig) fill() {
+ if c.Properties == nil {
+ c.Properties = &lzma.Properties{LC: 3, LP: 0, PB: 2}
+ }
+ if c.DictCap == 0 {
+ c.DictCap = 8 * 1024 * 1024
+ }
+ if c.BufSize == 0 {
+ c.BufSize = 4096
+ }
+ if c.BlockSize == 0 {
+ c.BlockSize = maxInt64
+ }
+ if c.CheckSum == 0 {
+ c.CheckSum = CRC64
+ }
+}
+
+// Verify checks the configuration for errors. Zero values will be
+// replaced by default values.
+func (c *WriterConfig) Verify() error {
+ if c == nil {
+ return errors.New("xz: writer configuration is nil")
+ }
+ c.fill()
+ lc := lzma.Writer2Config{
+ Properties: c.Properties,
+ DictCap: c.DictCap,
+ BufSize: c.BufSize,
+ Matcher: c.Matcher,
+ }
+ if err := lc.Verify(); err != nil {
+ return err
+ }
+ if c.BlockSize <= 0 {
+ return errors.New("xz: block size out of range")
+ }
+ if err := verifyFlags(c.CheckSum); err != nil {
+ return err
+ }
+ return nil
+}
+
+// filters creates the filter list for the given parameters.
+func (c *WriterConfig) filters() []filter {
+ return []filter{&lzmaFilter{int64(c.DictCap)}}
+}
+
+// maxInt64 defines the maximum 64-bit signed integer.
+const maxInt64 = 1<<63 - 1
+
+// verifyFilters checks the filter list for the length and the right
+// sequence of filters.
+func verifyFilters(f []filter) error {
+ if len(f) == 0 {
+ return errors.New("xz: no filters")
+ }
+ if len(f) > 4 {
+ return errors.New("xz: more than four filters")
+ }
+ for _, g := range f[:len(f)-1] {
+ if g.last() {
+ return errors.New("xz: last filter is not last")
+ }
+ }
+ if !f[len(f)-1].last() {
+ return errors.New("xz: wrong last filter")
+ }
+ return nil
+}
+
+// newFilterWriteCloser converts a filter list into a WriteCloser that
+// can be used by a blockWriter.
+func (c *WriterConfig) newFilterWriteCloser(w io.Writer, f []filter) (fw io.WriteCloser, err error) {
+ if err = verifyFilters(f); err != nil {
+ return nil, err
+ }
+ fw = nopWriteCloser(w)
+ for i := len(f) - 1; i >= 0; i-- {
+ fw, err = f[i].writeCloser(fw, c)
+ if err != nil {
+ return nil, err
+ }
+ }
+ return fw, nil
+}
+
+// nopWCloser implements a WriteCloser with a Close method not doing
+// anything.
+type nopWCloser struct {
+ io.Writer
+}
+
+// Close returns nil and doesn't do anything else.
+func (c nopWCloser) Close() error {
+ return nil
+}
+
+// nopWriteCloser converts the Writer into a WriteCloser with a Close
+// function that does nothing beside returning nil.
+func nopWriteCloser(w io.Writer) io.WriteCloser {
+ return nopWCloser{w}
+}
+
+// Writer compresses data written to it. It is an io.WriteCloser.
+type Writer struct {
+ WriterConfig
+
+ xz io.Writer
+ bw *blockWriter
+ newHash func() hash.Hash
+ h header
+ index []record
+ closed bool
+}
+
+// newBlockWriter creates a new block writer writes the header out.
+func (w *Writer) newBlockWriter() error {
+ var err error
+ w.bw, err = w.WriterConfig.newBlockWriter(w.xz, w.newHash())
+ if err != nil {
+ return err
+ }
+ if err = w.bw.writeHeader(w.xz); err != nil {
+ return err
+ }
+ return nil
+}
+
+// closeBlockWriter closes a block writer and records the sizes in the
+// index.
+func (w *Writer) closeBlockWriter() error {
+ var err error
+ if err = w.bw.Close(); err != nil {
+ return err
+ }
+ w.index = append(w.index, w.bw.record())
+ return nil
+}
+
+// NewWriter creates a new xz writer using default parameters.
+func NewWriter(xz io.Writer) (w *Writer, err error) {
+ return WriterConfig{}.NewWriter(xz)
+}
+
+// NewWriter creates a new Writer using the given configuration parameters.
+func (c WriterConfig) NewWriter(xz io.Writer) (w *Writer, err error) {
+ if err = c.Verify(); err != nil {
+ return nil, err
+ }
+ w = &Writer{
+ WriterConfig: c,
+ xz: xz,
+ h: header{c.CheckSum},
+ index: make([]record, 0, 4),
+ }
+ if w.newHash, err = newHashFunc(c.CheckSum); err != nil {
+ return nil, err
+ }
+ data, err := w.h.MarshalBinary()
+ if _, err = xz.Write(data); err != nil {
+ return nil, err
+ }
+ if err = w.newBlockWriter(); err != nil {
+ return nil, err
+ }
+ return w, nil
+
+}
+
+// Write compresses the uncompressed data provided.
+func (w *Writer) Write(p []byte) (n int, err error) {
+ if w.closed {
+ return 0, errClosed
+ }
+ for {
+ k, err := w.bw.Write(p[n:])
+ n += k
+ if err != errNoSpace {
+ return n, err
+ }
+ if err = w.closeBlockWriter(); err != nil {
+ return n, err
+ }
+ if err = w.newBlockWriter(); err != nil {
+ return n, err
+ }
+ }
+}
+
+// Close closes the writer and adds the footer to the Writer. Close
+// doesn't close the underlying writer.
+func (w *Writer) Close() error {
+ if w.closed {
+ return errClosed
+ }
+ w.closed = true
+ var err error
+ if err = w.closeBlockWriter(); err != nil {
+ return err
+ }
+
+ f := footer{flags: w.h.flags}
+ if f.indexSize, err = writeIndex(w.xz, w.index); err != nil {
+ return err
+ }
+ data, err := f.MarshalBinary()
+ if err != nil {
+ return err
+ }
+ if _, err = w.xz.Write(data); err != nil {
+ return err
+ }
+ return nil
+}
+
+// countingWriter is a writer that counts all data written to it.
+type countingWriter struct {
+ w io.Writer
+ n int64
+}
+
+// Write writes data to the countingWriter.
+func (cw *countingWriter) Write(p []byte) (n int, err error) {
+ n, err = cw.w.Write(p)
+ cw.n += int64(n)
+ if err == nil && cw.n < 0 {
+ return n, errors.New("xz: counter overflow")
+ }
+ return
+}
+
+// blockWriter is writes a single block.
+type blockWriter struct {
+ cxz countingWriter
+ // mw combines io.WriteCloser w and the hash.
+ mw io.Writer
+ w io.WriteCloser
+ n int64
+ blockSize int64
+ closed bool
+ headerLen int
+
+ filters []filter
+ hash hash.Hash
+}
+
+// newBlockWriter creates a new block writer.
+func (c *WriterConfig) newBlockWriter(xz io.Writer, hash hash.Hash) (bw *blockWriter, err error) {
+ bw = &blockWriter{
+ cxz: countingWriter{w: xz},
+ blockSize: c.BlockSize,
+ filters: c.filters(),
+ hash: hash,
+ }
+ bw.w, err = c.newFilterWriteCloser(&bw.cxz, bw.filters)
+ if err != nil {
+ return nil, err
+ }
+ bw.mw = io.MultiWriter(bw.w, bw.hash)
+ return bw, nil
+}
+
+// writeHeader writes the header. If the function is called after Close
+// the commpressedSize and uncompressedSize fields will be filled.
+func (bw *blockWriter) writeHeader(w io.Writer) error {
+ h := blockHeader{
+ compressedSize: -1,
+ uncompressedSize: -1,
+ filters: bw.filters,
+ }
+ if bw.closed {
+ h.compressedSize = bw.compressedSize()
+ h.uncompressedSize = bw.uncompressedSize()
+ }
+ data, err := h.MarshalBinary()
+ if err != nil {
+ return err
+ }
+ if _, err = w.Write(data); err != nil {
+ return err
+ }
+ bw.headerLen = len(data)
+ return nil
+}
+
+// compressed size returns the amount of data written to the underlying
+// stream.
+func (bw *blockWriter) compressedSize() int64 {
+ return bw.cxz.n
+}
+
+// uncompressedSize returns the number of data written to the
+// blockWriter
+func (bw *blockWriter) uncompressedSize() int64 {
+ return bw.n
+}
+
+// unpaddedSize returns the sum of the header length, the uncompressed
+// size of the block and the hash size.
+func (bw *blockWriter) unpaddedSize() int64 {
+ if bw.headerLen <= 0 {
+ panic("xz: block header not written")
+ }
+ n := int64(bw.headerLen)
+ n += bw.compressedSize()
+ n += int64(bw.hash.Size())
+ return n
+}
+
+// record returns the record for the current stream. Call Close before
+// calling this method.
+func (bw *blockWriter) record() record {
+ return record{bw.unpaddedSize(), bw.uncompressedSize()}
+}
+
+var errClosed = errors.New("xz: writer already closed")
+
+var errNoSpace = errors.New("xz: no space")
+
+// Write writes uncompressed data to the block writer.
+func (bw *blockWriter) Write(p []byte) (n int, err error) {
+ if bw.closed {
+ return 0, errClosed
+ }
+
+ t := bw.blockSize - bw.n
+ if int64(len(p)) > t {
+ err = errNoSpace
+ p = p[:t]
+ }
+
+ var werr error
+ n, werr = bw.mw.Write(p)
+ bw.n += int64(n)
+ if werr != nil {
+ return n, werr
+ }
+ return n, err
+}
+
+// Close closes the writer.
+func (bw *blockWriter) Close() error {
+ if bw.closed {
+ return errClosed
+ }
+ bw.closed = true
+ if err := bw.w.Close(); err != nil {
+ return err
+ }
+ s := bw.hash.Size()
+ k := padLen(bw.cxz.n)
+ p := make([]byte, k+s)
+ bw.hash.Sum(p[k:k])
+ if _, err := bw.cxz.w.Write(p); err != nil {
+ return err
+ }
+ return nil
+}