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-rw-r--r--vendor/github.com/klauspost/compress/flate/gen.go265
1 files changed, 0 insertions, 265 deletions
diff --git a/vendor/github.com/klauspost/compress/flate/gen.go b/vendor/github.com/klauspost/compress/flate/gen.go
deleted file mode 100644
index 154c89a48..000000000
--- a/vendor/github.com/klauspost/compress/flate/gen.go
+++ /dev/null
@@ -1,265 +0,0 @@
-// Copyright 2012 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.
-
-// +build ignore
-
-// This program generates fixedhuff.go
-// Invoke as
-//
-// go run gen.go -output fixedhuff.go
-
-package main
-
-import (
- "bytes"
- "flag"
- "fmt"
- "go/format"
- "io/ioutil"
- "log"
-)
-
-var filename = flag.String("output", "fixedhuff.go", "output file name")
-
-const maxCodeLen = 16
-
-// Note: the definition of the huffmanDecoder struct is copied from
-// inflate.go, as it is private to the implementation.
-
-// chunk & 15 is number of bits
-// chunk >> 4 is value, including table link
-
-const (
- huffmanChunkBits = 9
- huffmanNumChunks = 1 << huffmanChunkBits
- huffmanCountMask = 15
- huffmanValueShift = 4
-)
-
-type huffmanDecoder struct {
- min int // the minimum code length
- chunks [huffmanNumChunks]uint32 // chunks as described above
- links [][]uint32 // overflow links
- linkMask uint32 // mask the width of the link table
-}
-
-// Initialize Huffman decoding tables from array of code lengths.
-// Following this function, h is guaranteed to be initialized into a complete
-// tree (i.e., neither over-subscribed nor under-subscribed). The exception is a
-// degenerate case where the tree has only a single symbol with length 1. Empty
-// trees are permitted.
-func (h *huffmanDecoder) init(bits []int) bool {
- // Sanity enables additional runtime tests during Huffman
- // table construction. It's intended to be used during
- // development to supplement the currently ad-hoc unit tests.
- const sanity = false
-
- if h.min != 0 {
- *h = huffmanDecoder{}
- }
-
- // Count number of codes of each length,
- // compute min and max length.
- var count [maxCodeLen]int
- var min, max int
- for _, n := range bits {
- if n == 0 {
- continue
- }
- if min == 0 || n < min {
- min = n
- }
- if n > max {
- max = n
- }
- count[n]++
- }
-
- // Empty tree. The decompressor.huffSym function will fail later if the tree
- // is used. Technically, an empty tree is only valid for the HDIST tree and
- // not the HCLEN and HLIT tree. However, a stream with an empty HCLEN tree
- // is guaranteed to fail since it will attempt to use the tree to decode the
- // codes for the HLIT and HDIST trees. Similarly, an empty HLIT tree is
- // guaranteed to fail later since the compressed data section must be
- // composed of at least one symbol (the end-of-block marker).
- if max == 0 {
- return true
- }
-
- code := 0
- var nextcode [maxCodeLen]int
- for i := min; i <= max; i++ {
- code <<= 1
- nextcode[i] = code
- code += count[i]
- }
-
- // Check that the coding is complete (i.e., that we've
- // assigned all 2-to-the-max possible bit sequences).
- // Exception: To be compatible with zlib, we also need to
- // accept degenerate single-code codings. See also
- // TestDegenerateHuffmanCoding.
- if code != 1<<uint(max) && !(code == 1 && max == 1) {
- return false
- }
-
- h.min = min
- if max > huffmanChunkBits {
- numLinks := 1 << (uint(max) - huffmanChunkBits)
- h.linkMask = uint32(numLinks - 1)
-
- // create link tables
- link := nextcode[huffmanChunkBits+1] >> 1
- h.links = make([][]uint32, huffmanNumChunks-link)
- for j := uint(link); j < huffmanNumChunks; j++ {
- reverse := int(reverseByte[j>>8]) | int(reverseByte[j&0xff])<<8
- reverse >>= uint(16 - huffmanChunkBits)
- off := j - uint(link)
- if sanity && h.chunks[reverse] != 0 {
- panic("impossible: overwriting existing chunk")
- }
- h.chunks[reverse] = uint32(off<<huffmanValueShift | (huffmanChunkBits + 1))
- h.links[off] = make([]uint32, numLinks)
- }
- }
-
- for i, n := range bits {
- if n == 0 {
- continue
- }
- code := nextcode[n]
- nextcode[n]++
- chunk := uint32(i<<huffmanValueShift | n)
- reverse := int(reverseByte[code>>8]) | int(reverseByte[code&0xff])<<8
- reverse >>= uint(16 - n)
- if n <= huffmanChunkBits {
- for off := reverse; off < len(h.chunks); off += 1 << uint(n) {
- // We should never need to overwrite
- // an existing chunk. Also, 0 is
- // never a valid chunk, because the
- // lower 4 "count" bits should be
- // between 1 and 15.
- if sanity && h.chunks[off] != 0 {
- panic("impossible: overwriting existing chunk")
- }
- h.chunks[off] = chunk
- }
- } else {
- j := reverse & (huffmanNumChunks - 1)
- if sanity && h.chunks[j]&huffmanCountMask != huffmanChunkBits+1 {
- // Longer codes should have been
- // associated with a link table above.
- panic("impossible: not an indirect chunk")
- }
- value := h.chunks[j] >> huffmanValueShift
- linktab := h.links[value]
- reverse >>= huffmanChunkBits
- for off := reverse; off < len(linktab); off += 1 << uint(n-huffmanChunkBits) {
- if sanity && linktab[off] != 0 {
- panic("impossible: overwriting existing chunk")
- }
- linktab[off] = chunk
- }
- }
- }
-
- if sanity {
- // Above we've sanity checked that we never overwrote
- // an existing entry. Here we additionally check that
- // we filled the tables completely.
- for i, chunk := range h.chunks {
- if chunk == 0 {
- // As an exception, in the degenerate
- // single-code case, we allow odd
- // chunks to be missing.
- if code == 1 && i%2 == 1 {
- continue
- }
- panic("impossible: missing chunk")
- }
- }
- for _, linktab := range h.links {
- for _, chunk := range linktab {
- if chunk == 0 {
- panic("impossible: missing chunk")
- }
- }
- }
- }
-
- return true
-}
-
-func main() {
- flag.Parse()
-
- var h huffmanDecoder
- var bits [288]int
- initReverseByte()
- for i := 0; i < 144; i++ {
- bits[i] = 8
- }
- for i := 144; i < 256; i++ {
- bits[i] = 9
- }
- for i := 256; i < 280; i++ {
- bits[i] = 7
- }
- for i := 280; i < 288; i++ {
- bits[i] = 8
- }
- h.init(bits[:])
- if h.links != nil {
- log.Fatal("Unexpected links table in fixed Huffman decoder")
- }
-
- var buf bytes.Buffer
-
- fmt.Fprintf(&buf, `// Copyright 2013 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.`+"\n\n")
-
- fmt.Fprintln(&buf, "package flate")
- fmt.Fprintln(&buf)
- fmt.Fprintln(&buf, "// autogenerated by go run gen.go -output fixedhuff.go, DO NOT EDIT")
- fmt.Fprintln(&buf)
- fmt.Fprintln(&buf, "var fixedHuffmanDecoder = huffmanDecoder{")
- fmt.Fprintf(&buf, "\t%d,\n", h.min)
- fmt.Fprintln(&buf, "\t[huffmanNumChunks]uint32{")
- for i := 0; i < huffmanNumChunks; i++ {
- if i&7 == 0 {
- fmt.Fprintf(&buf, "\t\t")
- } else {
- fmt.Fprintf(&buf, " ")
- }
- fmt.Fprintf(&buf, "0x%04x,", h.chunks[i])
- if i&7 == 7 {
- fmt.Fprintln(&buf)
- }
- }
- fmt.Fprintln(&buf, "\t},")
- fmt.Fprintln(&buf, "\tnil, 0,")
- fmt.Fprintln(&buf, "}")
-
- data, err := format.Source(buf.Bytes())
- if err != nil {
- log.Fatal(err)
- }
- err = ioutil.WriteFile(*filename, data, 0644)
- if err != nil {
- log.Fatal(err)
- }
-}
-
-var reverseByte [256]byte
-
-func initReverseByte() {
- for x := 0; x < 256; x++ {
- var result byte
- for i := uint(0); i < 8; i++ {
- result |= byte(((x >> i) & 1) << (7 - i))
- }
- reverseByte[x] = result
- }
-}