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author | Daniel J Walsh <dwalsh@redhat.com> | 2018-07-08 07:55:30 -0400 |
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committer | Atomic Bot <atomic-devel@projectatomic.io> | 2018-07-19 18:43:32 +0000 |
commit | 98703eb204923f06555605c648fc165a55214520 (patch) | |
tree | a407bae8b3489d4f9b0f0d0f228658bbfe95a38e /vendor/github.com/ulikunitz/xz/writer.go | |
parent | c020db8cd21cb221cfbe36b264e0ec02999596ed (diff) | |
download | podman-98703eb204923f06555605c648fc165a55214520.tar.gz podman-98703eb204923f06555605c648fc165a55214520.tar.bz2 podman-98703eb204923f06555605c648fc165a55214520.zip |
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.go | 386 |
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 +} |