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authorUnknwon <u@gogs.io>2017-02-09 19:48:13 -0500
committerUnknwon <u@gogs.io>2017-02-09 19:48:13 -0500
commit2fd69f13d9599a6c58b47225565163fd7d87889f (patch)
treefd19e868e1c2e95a5fb83a268f6e393669d6ee79 /vendor/github.com/klauspost/compress/gzip
parenteb66060cd7b9bce996b1d75ae80ce1ef31d5ce62 (diff)
vendor: check in vendors
Bye bye glide...
Diffstat (limited to 'vendor/github.com/klauspost/compress/gzip')
-rw-r--r--vendor/github.com/klauspost/compress/gzip/gunzip.go344
-rw-r--r--vendor/github.com/klauspost/compress/gzip/gzip.go251
2 files changed, 595 insertions, 0 deletions
diff --git a/vendor/github.com/klauspost/compress/gzip/gunzip.go b/vendor/github.com/klauspost/compress/gzip/gunzip.go
new file mode 100644
index 00000000..e73fab3f
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/gzip/gunzip.go
@@ -0,0 +1,344 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package gzip implements reading and writing of gzip format compressed files,
+// as specified in RFC 1952.
+package gzip
+
+import (
+ "bufio"
+ "encoding/binary"
+ "errors"
+ "io"
+ "time"
+
+ "github.com/klauspost/compress/flate"
+ "github.com/klauspost/crc32"
+)
+
+const (
+ gzipID1 = 0x1f
+ gzipID2 = 0x8b
+ gzipDeflate = 8
+ flagText = 1 << 0
+ flagHdrCrc = 1 << 1
+ flagExtra = 1 << 2
+ flagName = 1 << 3
+ flagComment = 1 << 4
+)
+
+var (
+ // ErrChecksum is returned when reading GZIP data that has an invalid checksum.
+ ErrChecksum = errors.New("gzip: invalid checksum")
+ // ErrHeader is returned when reading GZIP data that has an invalid header.
+ ErrHeader = errors.New("gzip: invalid header")
+)
+
+var le = binary.LittleEndian
+
+// noEOF converts io.EOF to io.ErrUnexpectedEOF.
+func noEOF(err error) error {
+ if err == io.EOF {
+ return io.ErrUnexpectedEOF
+ }
+ return err
+}
+
+// The gzip file stores a header giving metadata about the compressed file.
+// That header is exposed as the fields of the Writer and Reader structs.
+//
+// Strings must be UTF-8 encoded and may only contain Unicode code points
+// U+0001 through U+00FF, due to limitations of the GZIP file format.
+type Header struct {
+ Comment string // comment
+ Extra []byte // "extra data"
+ ModTime time.Time // modification time
+ Name string // file name
+ OS byte // operating system type
+}
+
+// A Reader is an io.Reader that can be read to retrieve
+// uncompressed data from a gzip-format compressed file.
+//
+// In general, a gzip file can be a concatenation of gzip files,
+// each with its own header. Reads from the Reader
+// return the concatenation of the uncompressed data of each.
+// Only the first header is recorded in the Reader fields.
+//
+// Gzip files store a length and checksum of the uncompressed data.
+// The Reader will return a ErrChecksum when Read
+// reaches the end of the uncompressed data if it does not
+// have the expected length or checksum. Clients should treat data
+// returned by Read as tentative until they receive the io.EOF
+// marking the end of the data.
+type Reader struct {
+ Header // valid after NewReader or Reader.Reset
+ r flate.Reader
+ decompressor io.ReadCloser
+ digest uint32 // CRC-32, IEEE polynomial (section 8)
+ size uint32 // Uncompressed size (section 2.3.1)
+ buf [512]byte
+ err error
+ multistream bool
+}
+
+// NewReader creates a new Reader reading the given reader.
+// If r does not also implement io.ByteReader,
+// the decompressor may read more data than necessary from r.
+//
+// It is the caller's responsibility to call Close on the Reader when done.
+//
+// The Reader.Header fields will be valid in the Reader returned.
+func NewReader(r io.Reader) (*Reader, error) {
+ z := new(Reader)
+ if err := z.Reset(r); err != nil {
+ return nil, err
+ }
+ return z, nil
+}
+
+// Reset discards the Reader z's state and makes it equivalent to the
+// result of its original state from NewReader, but reading from r instead.
+// This permits reusing a Reader rather than allocating a new one.
+func (z *Reader) Reset(r io.Reader) error {
+ *z = Reader{
+ decompressor: z.decompressor,
+ multistream: true,
+ }
+ if rr, ok := r.(flate.Reader); ok {
+ z.r = rr
+ } else {
+ z.r = bufio.NewReader(r)
+ }
+ z.Header, z.err = z.readHeader()
+ return z.err
+}
+
+// Multistream controls whether the reader supports multistream files.
+//
+// If enabled (the default), the Reader expects the input to be a sequence
+// of individually gzipped data streams, each with its own header and
+// trailer, ending at EOF. The effect is that the concatenation of a sequence
+// of gzipped files is treated as equivalent to the gzip of the concatenation
+// of the sequence. This is standard behavior for gzip readers.
+//
+// Calling Multistream(false) disables this behavior; disabling the behavior
+// can be useful when reading file formats that distinguish individual gzip
+// data streams or mix gzip data streams with other data streams.
+// In this mode, when the Reader reaches the end of the data stream,
+// Read returns io.EOF. If the underlying reader implements io.ByteReader,
+// it will be left positioned just after the gzip stream.
+// To start the next stream, call z.Reset(r) followed by z.Multistream(false).
+// If there is no next stream, z.Reset(r) will return io.EOF.
+func (z *Reader) Multistream(ok bool) {
+ z.multistream = ok
+}
+
+// readString reads a NUL-terminated string from z.r.
+// It treats the bytes read as being encoded as ISO 8859-1 (Latin-1) and
+// will output a string encoded using UTF-8.
+// This method always updates z.digest with the data read.
+func (z *Reader) readString() (string, error) {
+ var err error
+ needConv := false
+ for i := 0; ; i++ {
+ if i >= len(z.buf) {
+ return "", ErrHeader
+ }
+ z.buf[i], err = z.r.ReadByte()
+ if err != nil {
+ return "", err
+ }
+ if z.buf[i] > 0x7f {
+ needConv = true
+ }
+ if z.buf[i] == 0 {
+ // Digest covers the NUL terminator.
+ z.digest = crc32.Update(z.digest, crc32.IEEETable, z.buf[:i+1])
+
+ // Strings are ISO 8859-1, Latin-1 (RFC 1952, section 2.3.1).
+ if needConv {
+ s := make([]rune, 0, i)
+ for _, v := range z.buf[:i] {
+ s = append(s, rune(v))
+ }
+ return string(s), nil
+ }
+ return string(z.buf[:i]), nil
+ }
+ }
+}
+
+// readHeader reads the GZIP header according to section 2.3.1.
+// This method does not set z.err.
+func (z *Reader) readHeader() (hdr Header, err error) {
+ if _, err = io.ReadFull(z.r, z.buf[:10]); err != nil {
+ // RFC 1952, section 2.2, says the following:
+ // A gzip file consists of a series of "members" (compressed data sets).
+ //
+ // Other than this, the specification does not clarify whether a
+ // "series" is defined as "one or more" or "zero or more". To err on the
+ // side of caution, Go interprets this to mean "zero or more".
+ // Thus, it is okay to return io.EOF here.
+ return hdr, err
+ }
+ if z.buf[0] != gzipID1 || z.buf[1] != gzipID2 || z.buf[2] != gzipDeflate {
+ return hdr, ErrHeader
+ }
+ flg := z.buf[3]
+ hdr.ModTime = time.Unix(int64(le.Uint32(z.buf[4:8])), 0)
+ // z.buf[8] is XFL and is currently ignored.
+ hdr.OS = z.buf[9]
+ z.digest = crc32.ChecksumIEEE(z.buf[:10])
+
+ if flg&flagExtra != 0 {
+ if _, err = io.ReadFull(z.r, z.buf[:2]); err != nil {
+ return hdr, noEOF(err)
+ }
+ z.digest = crc32.Update(z.digest, crc32.IEEETable, z.buf[:2])
+ data := make([]byte, le.Uint16(z.buf[:2]))
+ if _, err = io.ReadFull(z.r, data); err != nil {
+ return hdr, noEOF(err)
+ }
+ z.digest = crc32.Update(z.digest, crc32.IEEETable, data)
+ hdr.Extra = data
+ }
+
+ var s string
+ if flg&flagName != 0 {
+ if s, err = z.readString(); err != nil {
+ return hdr, err
+ }
+ hdr.Name = s
+ }
+
+ if flg&flagComment != 0 {
+ if s, err = z.readString(); err != nil {
+ return hdr, err
+ }
+ hdr.Comment = s
+ }
+
+ if flg&flagHdrCrc != 0 {
+ if _, err = io.ReadFull(z.r, z.buf[:2]); err != nil {
+ return hdr, noEOF(err)
+ }
+ digest := le.Uint16(z.buf[:2])
+ if digest != uint16(z.digest) {
+ return hdr, ErrHeader
+ }
+ }
+
+ z.digest = 0
+ if z.decompressor == nil {
+ z.decompressor = flate.NewReader(z.r)
+ } else {
+ z.decompressor.(flate.Resetter).Reset(z.r, nil)
+ }
+ return hdr, nil
+}
+
+// Read implements io.Reader, reading uncompressed bytes from its underlying Reader.
+func (z *Reader) Read(p []byte) (n int, err error) {
+ if z.err != nil {
+ return 0, z.err
+ }
+
+ n, z.err = z.decompressor.Read(p)
+ z.digest = crc32.Update(z.digest, crc32.IEEETable, p[:n])
+ z.size += uint32(n)
+ if z.err != io.EOF {
+ // In the normal case we return here.
+ return n, z.err
+ }
+
+ // Finished file; check checksum and size.
+ if _, err := io.ReadFull(z.r, z.buf[:8]); err != nil {
+ z.err = noEOF(err)
+ return n, z.err
+ }
+ digest := le.Uint32(z.buf[:4])
+ size := le.Uint32(z.buf[4:8])
+ if digest != z.digest || size != z.size {
+ z.err = ErrChecksum
+ return n, z.err
+ }
+ z.digest, z.size = 0, 0
+
+ // File is ok; check if there is another.
+ if !z.multistream {
+ return n, io.EOF
+ }
+ z.err = nil // Remove io.EOF
+
+ if _, z.err = z.readHeader(); z.err != nil {
+ return n, z.err
+ }
+
+ // Read from next file, if necessary.
+ if n > 0 {
+ return n, nil
+ }
+ return z.Read(p)
+}
+
+// Support the io.WriteTo interface for io.Copy and friends.
+func (z *Reader) WriteTo(w io.Writer) (int64, error) {
+ total := int64(0)
+ crcWriter := crc32.NewIEEE()
+ for {
+ if z.err != nil {
+ if z.err == io.EOF {
+ return total, nil
+ }
+ return total, z.err
+ }
+
+ // We write both to output and digest.
+ mw := io.MultiWriter(w, crcWriter)
+ n, err := z.decompressor.(io.WriterTo).WriteTo(mw)
+ total += n
+ z.size += uint32(n)
+ if err != nil {
+ z.err = err
+ return total, z.err
+ }
+
+ // Finished file; check checksum + size.
+ if _, err := io.ReadFull(z.r, z.buf[0:8]); err != nil {
+ if err == io.EOF {
+ err = io.ErrUnexpectedEOF
+ }
+ z.err = err
+ return total, err
+ }
+ z.digest = crcWriter.Sum32()
+ digest := le.Uint32(z.buf[:4])
+ size := le.Uint32(z.buf[4:8])
+ if digest != z.digest || size != z.size {
+ z.err = ErrChecksum
+ return total, z.err
+ }
+ z.digest, z.size = 0, 0
+
+ // File is ok; check if there is another.
+ if !z.multistream {
+ return total, nil
+ }
+ crcWriter.Reset()
+ z.err = nil // Remove io.EOF
+
+ if _, z.err = z.readHeader(); z.err != nil {
+ if z.err == io.EOF {
+ return total, nil
+ }
+ return total, z.err
+ }
+ }
+}
+
+// Close closes the Reader. It does not close the underlying io.Reader.
+// In order for the GZIP checksum to be verified, the reader must be
+// fully consumed until the io.EOF.
+func (z *Reader) Close() error { return z.decompressor.Close() }
diff --git a/vendor/github.com/klauspost/compress/gzip/gzip.go b/vendor/github.com/klauspost/compress/gzip/gzip.go
new file mode 100644
index 00000000..a0f3ed0f
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/gzip/gzip.go
@@ -0,0 +1,251 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gzip
+
+import (
+ "errors"
+ "fmt"
+ "io"
+
+ "github.com/klauspost/compress/flate"
+ "github.com/klauspost/crc32"
+)
+
+// These constants are copied from the flate package, so that code that imports
+// "compress/gzip" does not also have to import "compress/flate".
+const (
+ NoCompression = flate.NoCompression
+ BestSpeed = flate.BestSpeed
+ BestCompression = flate.BestCompression
+ DefaultCompression = flate.DefaultCompression
+ ConstantCompression = flate.ConstantCompression
+ HuffmanOnly = flate.HuffmanOnly
+)
+
+// A Writer is an io.WriteCloser.
+// Writes to a Writer are compressed and written to w.
+type Writer struct {
+ Header // written at first call to Write, Flush, or Close
+ w io.Writer
+ level int
+ wroteHeader bool
+ compressor *flate.Writer
+ digest uint32 // CRC-32, IEEE polynomial (section 8)
+ size uint32 // Uncompressed size (section 2.3.1)
+ closed bool
+ buf [10]byte
+ err error
+}
+
+// NewWriter returns a new Writer.
+// Writes to the returned writer are compressed and written to w.
+//
+// It is the caller's responsibility to call Close on the WriteCloser when done.
+// Writes may be buffered and not flushed until Close.
+//
+// Callers that wish to set the fields in Writer.Header must do so before
+// the first call to Write, Flush, or Close.
+func NewWriter(w io.Writer) *Writer {
+ z, _ := NewWriterLevel(w, DefaultCompression)
+ return z
+}
+
+// NewWriterLevel is like NewWriter but specifies the compression level instead
+// of assuming DefaultCompression.
+//
+// The compression level can be DefaultCompression, NoCompression, or any
+// integer value between BestSpeed and BestCompression inclusive. The error
+// returned will be nil if the level is valid.
+func NewWriterLevel(w io.Writer, level int) (*Writer, error) {
+ if level < HuffmanOnly || level > BestCompression {
+ return nil, fmt.Errorf("gzip: invalid compression level: %d", level)
+ }
+ z := new(Writer)
+ z.init(w, level)
+ return z, nil
+}
+
+func (z *Writer) init(w io.Writer, level int) {
+ compressor := z.compressor
+ if compressor != nil {
+ compressor.Reset(w)
+ }
+ *z = Writer{
+ Header: Header{
+ OS: 255, // unknown
+ },
+ w: w,
+ level: level,
+ compressor: compressor,
+ }
+}
+
+// Reset discards the Writer z's state and makes it equivalent to the
+// result of its original state from NewWriter or NewWriterLevel, but
+// writing to w instead. This permits reusing a Writer rather than
+// allocating a new one.
+func (z *Writer) Reset(w io.Writer) {
+ z.init(w, z.level)
+}
+
+// writeBytes writes a length-prefixed byte slice to z.w.
+func (z *Writer) writeBytes(b []byte) error {
+ if len(b) > 0xffff {
+ return errors.New("gzip.Write: Extra data is too large")
+ }
+ le.PutUint16(z.buf[:2], uint16(len(b)))
+ _, err := z.w.Write(z.buf[:2])
+ if err != nil {
+ return err
+ }
+ _, err = z.w.Write(b)
+ return err
+}
+
+// writeString writes a UTF-8 string s in GZIP's format to z.w.
+// GZIP (RFC 1952) specifies that strings are NUL-terminated ISO 8859-1 (Latin-1).
+func (z *Writer) writeString(s string) (err error) {
+ // GZIP stores Latin-1 strings; error if non-Latin-1; convert if non-ASCII.
+ needconv := false
+ for _, v := range s {
+ if v == 0 || v > 0xff {
+ return errors.New("gzip.Write: non-Latin-1 header string")
+ }
+ if v > 0x7f {
+ needconv = true
+ }
+ }
+ if needconv {
+ b := make([]byte, 0, len(s))
+ for _, v := range s {
+ b = append(b, byte(v))
+ }
+ _, err = z.w.Write(b)
+ } else {
+ _, err = io.WriteString(z.w, s)
+ }
+ if err != nil {
+ return err
+ }
+ // GZIP strings are NUL-terminated.
+ z.buf[0] = 0
+ _, err = z.w.Write(z.buf[:1])
+ return err
+}
+
+// Write writes a compressed form of p to the underlying io.Writer. The
+// compressed bytes are not necessarily flushed until the Writer is closed.
+func (z *Writer) Write(p []byte) (int, error) {
+ if z.err != nil {
+ return 0, z.err
+ }
+ var n int
+ // Write the GZIP header lazily.
+ if !z.wroteHeader {
+ z.wroteHeader = true
+ z.buf[0] = gzipID1
+ z.buf[1] = gzipID2
+ z.buf[2] = gzipDeflate
+ z.buf[3] = 0
+ if z.Extra != nil {
+ z.buf[3] |= 0x04
+ }
+ if z.Name != "" {
+ z.buf[3] |= 0x08
+ }
+ if z.Comment != "" {
+ z.buf[3] |= 0x10
+ }
+ le.PutUint32(z.buf[4:8], uint32(z.ModTime.Unix()))
+ if z.level == BestCompression {
+ z.buf[8] = 2
+ } else if z.level == BestSpeed {
+ z.buf[8] = 4
+ } else {
+ z.buf[8] = 0
+ }
+ z.buf[9] = z.OS
+ n, z.err = z.w.Write(z.buf[:10])
+ if z.err != nil {
+ return n, z.err
+ }
+ if z.Extra != nil {
+ z.err = z.writeBytes(z.Extra)
+ if z.err != nil {
+ return n, z.err
+ }
+ }
+ if z.Name != "" {
+ z.err = z.writeString(z.Name)
+ if z.err != nil {
+ return n, z.err
+ }
+ }
+ if z.Comment != "" {
+ z.err = z.writeString(z.Comment)
+ if z.err != nil {
+ return n, z.err
+ }
+ }
+ if z.compressor == nil {
+ z.compressor, _ = flate.NewWriter(z.w, z.level)
+ }
+ }
+ z.size += uint32(len(p))
+ z.digest = crc32.Update(z.digest, crc32.IEEETable, p)
+ n, z.err = z.compressor.Write(p)
+ return n, z.err
+}
+
+// Flush flushes any pending compressed data to the underlying writer.
+//
+// It is useful mainly in compressed network protocols, to ensure that
+// a remote reader has enough data to reconstruct a packet. Flush does
+// not return until the data has been written. If the underlying
+// writer returns an error, Flush returns that error.
+//
+// In the terminology of the zlib library, Flush is equivalent to Z_SYNC_FLUSH.
+func (z *Writer) Flush() error {
+ if z.err != nil {
+ return z.err
+ }
+ if z.closed {
+ return nil
+ }
+ if !z.wroteHeader {
+ z.Write(nil)
+ if z.err != nil {
+ return z.err
+ }
+ }
+ z.err = z.compressor.Flush()
+ return z.err
+}
+
+// Close closes the Writer, flushing any unwritten data to the underlying
+// io.Writer, but does not close the underlying io.Writer.
+func (z *Writer) Close() error {
+ if z.err != nil {
+ return z.err
+ }
+ if z.closed {
+ return nil
+ }
+ z.closed = true
+ if !z.wroteHeader {
+ z.Write(nil)
+ if z.err != nil {
+ return z.err
+ }
+ }
+ z.err = z.compressor.Close()
+ if z.err != nil {
+ return z.err
+ }
+ le.PutUint32(z.buf[:4], z.digest)
+ le.PutUint32(z.buf[4:8], z.size)
+ _, z.err = z.w.Write(z.buf[:8])
+ return z.err
+}