1 files changed, 0 insertions, 272 deletions
diff --git a/vendor/golang.org/x/image/tiff/lzw/reader.go b/vendor/golang.org/x/image/tiff/lzw/reader.go
deleted file mode 100644
index 78204ba9..00000000
--- a/vendor/golang.org/x/image/tiff/lzw/reader.go
+++ /dev/null
@@ -1,272 +0,0 @@
-// Copyright 2011 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 lzw implements the Lempel-Ziv-Welch compressed data format,
-// described in T. A. Welch, ``A Technique for High-Performance Data
-// Compression'', Computer, 17(6) (June 1984), pp 8-19.
-//
-// In particular, it implements LZW as used by the TIFF file format, including
-// an "off by one" algorithmic difference when compared to standard LZW.
-package lzw // import "golang.org/x/image/tiff/lzw"
-
-/*
-This file was branched from src/pkg/compress/lzw/reader.go in the
-standard library. Differences from the original are marked with "NOTE".
-
-The tif_lzw.c file in the libtiff C library has this comment:
-
-----
-The 5.0 spec describes a different algorithm than Aldus
-implements.  Specifically, Aldus does code length transitions
-one code earlier than should be done (for real LZW).
-Earlier versions of this library implemented the correct
-LZW algorithm, but emitted codes in a bit order opposite
-to the TIFF spec.  Thus, to maintain compatibility w/ Aldus
-we interpret MSB-LSB ordered codes to be images written w/
-old versions of this library, but otherwise adhere to the
-Aldus "off by one" algorithm.
-----
-
-The Go code doesn't read (invalid) TIFF files written by old versions of
-libtiff, but the LZW algorithm in this package still differs from the one in
-Go's standard package library to accomodate this "off by one" in valid TIFFs.
-*/
-
-import (
-	"bufio"
-	"errors"
-	"fmt"
-	"io"
-)
-
-// Order specifies the bit ordering in an LZW data stream.
-type Order int
-
-const (
-	// LSB means Least Significant Bits first, as used in the GIF file format.
-	LSB Order = iota
-	// MSB means Most Significant Bits first, as used in the TIFF and PDF
-	// file formats.
-	MSB
-)
-
-const (
-	maxWidth           = 12
-	decoderInvalidCode = 0xffff
-	flushBuffer        = 1 << maxWidth
-)
-
-// decoder is the state from which the readXxx method converts a byte
-// stream into a code stream.
-type decoder struct {
-	r        io.ByteReader
-	bits     uint32
-	nBits    uint
-	width    uint
-	read     func(*decoder) (uint16, error) // readLSB or readMSB
-	litWidth int                            // width in bits of literal codes
-	err      error
-
-	// The first 1<<litWidth codes are literal codes.
-	// The next two codes mean clear and EOF.
-	// Other valid codes are in the range [lo, hi] where lo := clear + 2,
-	// with the upper bound incrementing on each code seen.
-	// overflow is the code at which hi overflows the code width. NOTE: TIFF's LZW is "off by one".
-	// last is the most recently seen code, or decoderInvalidCode.
-	clear, eof, hi, overflow, last uint16
-
-	// Each code c in [lo, hi] expands to two or more bytes. For c != hi:
-	//   suffix[c] is the last of these bytes.
-	//   prefix[c] is the code for all but the last byte.
-	//   This code can either be a literal code or another code in [lo, c).
-	// The c == hi case is a special case.
-	suffix [1 << maxWidth]uint8
-	prefix [1 << maxWidth]uint16
-
-	// output is the temporary output buffer.
-	// Literal codes are accumulated from the start of the buffer.
-	// Non-literal codes decode to a sequence of suffixes that are first
-	// written right-to-left from the end of the buffer before being copied
-	// to the start of the buffer.
-	// It is flushed when it contains >= 1<<maxWidth bytes,
-	// so that there is always room to decode an entire code.
-	output [2 * 1 << maxWidth]byte
-	o      int    // write index into output
-	toRead []byte // bytes to return from Read
-}
-
-// readLSB returns the next code for "Least Significant Bits first" data.
-func (d *decoder) readLSB() (uint16, error) {
-	for d.nBits < d.width {
-		x, err := d.r.ReadByte()
-		if err != nil {
-			return 0, err
-		}
-		d.bits |= uint32(x) << d.nBits
-		d.nBits += 8
-	}
-	code := uint16(d.bits & (1<<d.width - 1))
-	d.bits >>= d.width
-	d.nBits -= d.width
-	return code, nil
-}
-
-// readMSB returns the next code for "Most Significant Bits first" data.
-func (d *decoder) readMSB() (uint16, error) {
-	for d.nBits < d.width {
-		x, err := d.r.ReadByte()
-		if err != nil {
-			return 0, err
-		}
-		d.bits |= uint32(x) << (24 - d.nBits)
-		d.nBits += 8
-	}
-	code := uint16(d.bits >> (32 - d.width))
-	d.bits <<= d.width
-	d.nBits -= d.width
-	return code, nil
-}
-
-func (d *decoder) Read(b []byte) (int, error) {
-	for {
-		if len(d.toRead) > 0 {
-			n := copy(b, d.toRead)
-			d.toRead = d.toRead[n:]
-			return n, nil
-		}
-		if d.err != nil {
-			return 0, d.err
-		}
-		d.decode()
-	}
-}
-
-// decode decompresses bytes from r and leaves them in d.toRead.
-// read specifies how to decode bytes into codes.
-// litWidth is the width in bits of literal codes.
-func (d *decoder) decode() {
-	// Loop over the code stream, converting codes into decompressed bytes.
-loop:
-	for {
-		code, err := d.read(d)
-		if err != nil {
-			if err == io.EOF {
-				err = io.ErrUnexpectedEOF
-			}
-			d.err = err
-			break
-		}
-		switch {
-		case code < d.clear:
-			// We have a literal code.
-			d.output[d.o] = uint8(code)
-			d.o++
-			if d.last != decoderInvalidCode {
-				// Save what the hi code expands to.
-				d.suffix[d.hi] = uint8(code)
-				d.prefix[d.hi] = d.last
-			}
-		case code == d.clear:
-			d.width = 1 + uint(d.litWidth)
-			d.hi = d.eof
-			d.overflow = 1 << d.width
-			d.last = decoderInvalidCode
-			continue
-		case code == d.eof:
-			d.err = io.EOF
-			break loop
-		case code <= d.hi:
-			c, i := code, len(d.output)-1
-			if code == d.hi && d.last != decoderInvalidCode {
-				// code == hi is a special case which expands to the last expansion
-				// followed by the head of the last expansion. To find the head, we walk
-				// the prefix chain until we find a literal code.
-				c = d.last
-				for c >= d.clear {
-					c = d.prefix[c]
-				}
-				d.output[i] = uint8(c)
-				i--
-				c = d.last
-			}
-			// Copy the suffix chain into output and then write that to w.
-			for c >= d.clear {
-				d.output[i] = d.suffix[c]
-				i--
-				c = d.prefix[c]
-			}
-			d.output[i] = uint8(c)
-			d.o += copy(d.output[d.o:], d.output[i:])
-			if d.last != decoderInvalidCode {
-				// Save what the hi code expands to.
-				d.suffix[d.hi] = uint8(c)
-				d.prefix[d.hi] = d.last
-			}
-		default:
-			d.err = errors.New("lzw: invalid code")
-			break loop
-		}
-		d.last, d.hi = code, d.hi+1
-		if d.hi+1 >= d.overflow { // NOTE: the "+1" is where TIFF's LZW differs from the standard algorithm.
-			if d.width == maxWidth {
-				d.last = decoderInvalidCode
-			} else {
-				d.width++
-				d.overflow <<= 1
-			}
-		}
-		if d.o >= flushBuffer {
-			break
-		}
-	}
-	// Flush pending output.
-	d.toRead = d.output[:d.o]
-	d.o = 0
-}
-
-var errClosed = errors.New("lzw: reader/writer is closed")
-
-func (d *decoder) Close() error {
-	d.err = errClosed // in case any Reads come along
-	return nil
-}
-
-// NewReader creates a new io.ReadCloser.
-// Reads from the returned io.ReadCloser read and decompress data from r.
-// 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 ReadCloser when
-// finished reading.
-// The number of bits to use for literal codes, litWidth, must be in the
-// range [2,8] and is typically 8. It must equal the litWidth
-// used during compression.
-func NewReader(r io.Reader, order Order, litWidth int) io.ReadCloser {
-	d := new(decoder)
-	switch order {
-	case LSB:
-		d.read = (*decoder).readLSB
-	case MSB:
-		d.read = (*decoder).readMSB
-	default:
-		d.err = errors.New("lzw: unknown order")
-		return d
-	}
-	if litWidth < 2 || 8 < litWidth {
-		d.err = fmt.Errorf("lzw: litWidth %d out of range", litWidth)
-		return d
-	}
-	if br, ok := r.(io.ByteReader); ok {
-		d.r = br
-	} else {
-		d.r = bufio.NewReader(r)
-	}
-	d.litWidth = litWidth
-	d.width = 1 + uint(litWidth)
-	d.clear = uint16(1) << uint(litWidth)
-	d.eof, d.hi = d.clear+1, d.clear+1
-	d.overflow = uint16(1) << d.width
-	d.last = decoderInvalidCode
-
-	return d
-}