diff options
Diffstat (limited to 'gcc-4.8.1/libgo/go/compress/gzip/gzip.go')
| -rw-r--r-- | gcc-4.8.1/libgo/go/compress/gzip/gzip.go | 217 |
1 files changed, 0 insertions, 217 deletions
diff --git a/gcc-4.8.1/libgo/go/compress/gzip/gzip.go b/gcc-4.8.1/libgo/go/compress/gzip/gzip.go deleted file mode 100644 index 3035dfffc..000000000 --- a/gcc-4.8.1/libgo/go/compress/gzip/gzip.go +++ /dev/null @@ -1,217 +0,0 @@ -// 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 ( - "compress/flate" - "errors" - "fmt" - "hash" - "hash/crc32" - "io" -) - -// 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 -) - -// A Writer is an io.WriteCloser that satisfies writes by compressing data written -// to its wrapped io.Writer. -type Writer struct { - Header - w io.Writer - level int - compressor io.WriteCloser - digest hash.Hash32 - size uint32 - closed bool - buf [10]byte - err error -} - -// NewWriter creates a new Writer that satisfies writes by compressing data -// 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 or Close. The Comment and Name header fields are -// UTF-8 strings in Go, but the underlying format requires NUL-terminated ISO -// 8859-1 (Latin-1). NUL or non-Latin-1 runes in those strings will lead to an -// error on Write. -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 < DefaultCompression || level > BestCompression { - return nil, fmt.Errorf("gzip: invalid compression level: %d", level) - } - return &Writer{ - Header: Header{ - OS: 255, // unknown - }, - w: w, - level: level, - digest: crc32.NewIEEE(), - }, nil -} - -// GZIP (RFC 1952) is little-endian, unlike ZLIB (RFC 1950). -func put2(p []byte, v uint16) { - p[0] = uint8(v >> 0) - p[1] = uint8(v >> 8) -} - -func put4(p []byte, v uint32) { - p[0] = uint8(v >> 0) - p[1] = uint8(v >> 8) - p[2] = uint8(v >> 16) - p[3] = uint8(v >> 24) -} - -// 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") - } - put2(z.buf[0:2], uint16(len(b))) - _, err := z.w.Write(z.buf[0:2]) - 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[0:1]) - 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.compressor == nil { - 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 - } - put4(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[0:10]) - 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 - } - } - z.compressor, _ = flate.NewWriter(z.w, z.level) - } - z.size += uint32(len(p)) - z.digest.Write(p) - n, z.err = z.compressor.Write(p) - return n, z.err -} - -// Close closes the Writer. It 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.compressor == nil { - z.Write(nil) - if z.err != nil { - return z.err - } - } - z.err = z.compressor.Close() - if z.err != nil { - return z.err - } - put4(z.buf[0:4], z.digest.Sum32()) - put4(z.buf[4:8], z.size) - _, z.err = z.w.Write(z.buf[0:8]) - return z.err -} |