diff options
Diffstat (limited to 'vendor/github.com/klauspost/compress/flate/inflate.go')
| -rw-r--r-- | vendor/github.com/klauspost/compress/flate/inflate.go | 71 |
1 files changed, 64 insertions, 7 deletions
diff --git a/vendor/github.com/klauspost/compress/flate/inflate.go b/vendor/github.com/klauspost/compress/flate/inflate.go index 800d0ce9e..6dc5b5d06 100644 --- a/vendor/github.com/klauspost/compress/flate/inflate.go +++ b/vendor/github.com/klauspost/compress/flate/inflate.go @@ -9,6 +9,7 @@ package flate import ( "bufio" + "fmt" "io" "math/bits" "strconv" @@ -24,6 +25,8 @@ const ( maxNumLit = 286 maxNumDist = 30 numCodes = 19 // number of codes in Huffman meta-code + + debugDecode = false ) // Initialize the fixedHuffmanDecoder only once upon first use. @@ -104,8 +107,8 @@ const ( type huffmanDecoder struct { min int // the minimum code length - chunks *[huffmanNumChunks]uint32 // chunks as described above - links [][]uint32 // overflow links + chunks *[huffmanNumChunks]uint16 // chunks as described above + links [][]uint16 // overflow links linkMask uint32 // mask the width of the link table } @@ -121,7 +124,7 @@ func (h *huffmanDecoder) init(lengths []int) bool { const sanity = false if h.chunks == nil { - h.chunks = &[huffmanNumChunks]uint32{} + h.chunks = &[huffmanNumChunks]uint16{} } if h.min != 0 { *h = huffmanDecoder{chunks: h.chunks, links: h.links} @@ -169,6 +172,9 @@ func (h *huffmanDecoder) init(lengths []int) bool { // accept degenerate single-code codings. See also // TestDegenerateHuffmanCoding. if code != 1<<uint(max) && !(code == 1 && max == 1) { + if debugDecode { + fmt.Println("coding failed, code, max:", code, max, code == 1<<uint(max), code == 1 && max == 1, "(one should be true)") + } return false } @@ -185,7 +191,7 @@ func (h *huffmanDecoder) init(lengths []int) bool { // create link tables link := nextcode[huffmanChunkBits+1] >> 1 if cap(h.links) < huffmanNumChunks-link { - h.links = make([][]uint32, huffmanNumChunks-link) + h.links = make([][]uint16, huffmanNumChunks-link) } else { h.links = h.links[:huffmanNumChunks-link] } @@ -196,9 +202,9 @@ func (h *huffmanDecoder) init(lengths []int) bool { if sanity && h.chunks[reverse] != 0 { panic("impossible: overwriting existing chunk") } - h.chunks[reverse] = uint32(off<<huffmanValueShift | (huffmanChunkBits + 1)) + h.chunks[reverse] = uint16(off<<huffmanValueShift | (huffmanChunkBits + 1)) if cap(h.links[off]) < numLinks { - h.links[off] = make([]uint32, numLinks) + h.links[off] = make([]uint16, numLinks) } else { links := h.links[off][:0] h.links[off] = links[:numLinks] @@ -214,7 +220,7 @@ func (h *huffmanDecoder) init(lengths []int) bool { } code := nextcode[n] nextcode[n]++ - chunk := uint32(i<<huffmanValueShift | n) + chunk := uint16(i<<huffmanValueShift | n) reverse := int(bits.Reverse16(uint16(code))) reverse >>= uint(16 - n) if n <= huffmanChunkBits { @@ -347,6 +353,9 @@ func (f *decompressor) nextBlock() { f.huffmanBlock() default: // 3 is reserved. + if debugDecode { + fmt.Println("reserved data block encountered") + } f.err = CorruptInputError(f.roffset) } } @@ -425,11 +434,17 @@ func (f *decompressor) readHuffman() error { } nlit := int(f.b&0x1F) + 257 if nlit > maxNumLit { + if debugDecode { + fmt.Println("nlit > maxNumLit", nlit) + } return CorruptInputError(f.roffset) } f.b >>= 5 ndist := int(f.b&0x1F) + 1 if ndist > maxNumDist { + if debugDecode { + fmt.Println("ndist > maxNumDist", ndist) + } return CorruptInputError(f.roffset) } f.b >>= 5 @@ -453,6 +468,9 @@ func (f *decompressor) readHuffman() error { f.codebits[codeOrder[i]] = 0 } if !f.h1.init(f.codebits[0:]) { + if debugDecode { + fmt.Println("init codebits failed") + } return CorruptInputError(f.roffset) } @@ -480,6 +498,9 @@ func (f *decompressor) readHuffman() error { rep = 3 nb = 2 if i == 0 { + if debugDecode { + fmt.Println("i==0") + } return CorruptInputError(f.roffset) } b = f.bits[i-1] @@ -494,6 +515,9 @@ func (f *decompressor) readHuffman() error { } for f.nb < nb { if err := f.moreBits(); err != nil { + if debugDecode { + fmt.Println("morebits:", err) + } return err } } @@ -501,6 +525,9 @@ func (f *decompressor) readHuffman() error { f.b >>= nb f.nb -= nb if i+rep > n { + if debugDecode { + fmt.Println("i+rep > n", i, rep, n) + } return CorruptInputError(f.roffset) } for j := 0; j < rep; j++ { @@ -510,6 +537,9 @@ func (f *decompressor) readHuffman() error { } if !f.h1.init(f.bits[0:nlit]) || !f.h2.init(f.bits[nlit:nlit+ndist]) { + if debugDecode { + fmt.Println("init2 failed") + } return CorruptInputError(f.roffset) } @@ -587,12 +617,18 @@ readLiteral: length = 258 n = 0 default: + if debugDecode { + fmt.Println(v, ">= maxNumLit") + } f.err = CorruptInputError(f.roffset) return } if n > 0 { for f.nb < n { if err = f.moreBits(); err != nil { + if debugDecode { + fmt.Println("morebits n>0:", err) + } f.err = err return } @@ -606,6 +642,9 @@ readLiteral: if f.hd == nil { for f.nb < 5 { if err = f.moreBits(); err != nil { + if debugDecode { + fmt.Println("morebits f.nb<5:", err) + } f.err = err return } @@ -615,6 +654,9 @@ readLiteral: f.nb -= 5 } else { if dist, err = f.huffSym(f.hd); err != nil { + if debugDecode { + fmt.Println("huffsym:", err) + } f.err = err return } @@ -629,6 +671,9 @@ readLiteral: extra := (dist & 1) << nb for f.nb < nb { if err = f.moreBits(); err != nil { + if debugDecode { + fmt.Println("morebits f.nb<nb:", err) + } f.err = err return } @@ -638,12 +683,18 @@ readLiteral: f.nb -= nb dist = 1<<(nb+1) + 1 + extra default: + if debugDecode { + fmt.Println("dist too big:", dist, maxNumDist) + } f.err = CorruptInputError(f.roffset) return } // No check on length; encoding can be prescient. if dist > f.dict.histSize() { + if debugDecode { + fmt.Println("dist > f.dict.histSize():", dist, f.dict.histSize()) + } f.err = CorruptInputError(f.roffset) return } @@ -688,6 +739,9 @@ func (f *decompressor) dataBlock() { n := int(f.buf[0]) | int(f.buf[1])<<8 nn := int(f.buf[2]) | int(f.buf[3])<<8 if uint16(nn) != uint16(^n) { + if debugDecode { + fmt.Println("uint16(nn) != uint16(^n)", nn, ^n) + } f.err = CorruptInputError(f.roffset) return } @@ -789,6 +843,9 @@ func (f *decompressor) huffSym(h *huffmanDecoder) (int, error) { if n == 0 { f.b = b f.nb = nb + if debugDecode { + fmt.Println("huffsym: n==0") + } f.err = CorruptInputError(f.roffset) return 0, f.err } |