diff options
Diffstat (limited to 'vendor/github.com/klauspost/compress/flate/inflate_gen.go')
| -rw-r--r-- | vendor/github.com/klauspost/compress/flate/inflate_gen.go | 1283 |
1 files changed, 0 insertions, 1283 deletions
diff --git a/vendor/github.com/klauspost/compress/flate/inflate_gen.go b/vendor/github.com/klauspost/compress/flate/inflate_gen.go deleted file mode 100644 index 2b2f993f7..000000000 --- a/vendor/github.com/klauspost/compress/flate/inflate_gen.go +++ /dev/null @@ -1,1283 +0,0 @@ -// Code generated by go generate gen_inflate.go. DO NOT EDIT. - -package flate - -import ( - "bufio" - "bytes" - "fmt" - "math/bits" - "strings" -) - -// Decode a single Huffman block from f. -// hl and hd are the Huffman states for the lit/length values -// and the distance values, respectively. If hd == nil, using the -// fixed distance encoding associated with fixed Huffman blocks. -func (f *decompressor) huffmanBytesBuffer() { - const ( - stateInit = iota // Zero value must be stateInit - stateDict - ) - fr := f.r.(*bytes.Buffer) - - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - fnb, fb, dict := f.nb, f.b, &f.dict - - switch f.stepState { - case stateInit: - goto readLiteral - case stateDict: - goto copyHistory - } - -readLiteral: - // Read literal and/or (length, distance) according to RFC section 3.2.3. - { - var v int - { - // Inlined v, err := f.huffSym(f.hl) - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hl.maxRead) - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hl.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hl.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hl.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - v = int(chunk >> huffmanValueShift) - break - } - } - } - - var length int - switch { - case v < 256: - dict.writeByte(byte(v)) - if dict.availWrite() == 0 { - f.toRead = dict.readFlush() - f.step = huffmanBytesBuffer - f.stepState = stateInit - f.b, f.nb = fb, fnb - return - } - goto readLiteral - case v == 256: - f.b, f.nb = fb, fnb - f.finishBlock() - return - // otherwise, reference to older data - case v < 265: - length = v - (257 - 3) - case v < maxNumLit: - val := decCodeToLen[(v - 257)] - length = int(val.length) + 3 - n := uint(val.extra) - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits n>0:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - length += int(fb & bitMask32[n]) - fb >>= n & regSizeMaskUint32 - fnb -= n - default: - if debugDecode { - fmt.Println(v, ">= maxNumLit") - } - f.err = CorruptInputError(f.roffset) - f.b, f.nb = fb, fnb - return - } - - var dist uint32 - if f.hd == nil { - for fnb < 5 { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<5:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - dist = uint32(bits.Reverse8(uint8(fb & 0x1F << 3))) - fb >>= 5 - fnb -= 5 - } else { - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hd.maxRead) - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hd.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hd.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hd.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - dist = uint32(chunk >> huffmanValueShift) - break - } - } - } - - switch { - case dist < 4: - dist++ - case dist < maxNumDist: - nb := uint(dist-2) >> 1 - // have 1 bit in bottom of dist, need nb more. - extra := (dist & 1) << (nb & regSizeMaskUint32) - for fnb < nb { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<nb:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - extra |= fb & bitMask32[nb] - fb >>= nb & regSizeMaskUint32 - fnb -= nb - dist = 1<<((nb+1)®SizeMaskUint32) + 1 + extra - // slower: dist = bitMask32[nb+1] + 2 + extra - default: - f.b, f.nb = fb, fnb - 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 > uint32(dict.histSize()) { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("dist > dict.histSize():", dist, dict.histSize()) - } - f.err = CorruptInputError(f.roffset) - return - } - - f.copyLen, f.copyDist = length, int(dist) - goto copyHistory - } - -copyHistory: - // Perform a backwards copy according to RFC section 3.2.3. - { - cnt := dict.tryWriteCopy(f.copyDist, f.copyLen) - if cnt == 0 { - cnt = dict.writeCopy(f.copyDist, f.copyLen) - } - f.copyLen -= cnt - - if dict.availWrite() == 0 || f.copyLen > 0 { - f.toRead = dict.readFlush() - f.step = huffmanBytesBuffer // We need to continue this work - f.stepState = stateDict - f.b, f.nb = fb, fnb - return - } - goto readLiteral - } - // Not reached -} - -// Decode a single Huffman block from f. -// hl and hd are the Huffman states for the lit/length values -// and the distance values, respectively. If hd == nil, using the -// fixed distance encoding associated with fixed Huffman blocks. -func (f *decompressor) huffmanBytesReader() { - const ( - stateInit = iota // Zero value must be stateInit - stateDict - ) - fr := f.r.(*bytes.Reader) - - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - fnb, fb, dict := f.nb, f.b, &f.dict - - switch f.stepState { - case stateInit: - goto readLiteral - case stateDict: - goto copyHistory - } - -readLiteral: - // Read literal and/or (length, distance) according to RFC section 3.2.3. - { - var v int - { - // Inlined v, err := f.huffSym(f.hl) - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hl.maxRead) - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hl.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hl.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hl.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - v = int(chunk >> huffmanValueShift) - break - } - } - } - - var length int - switch { - case v < 256: - dict.writeByte(byte(v)) - if dict.availWrite() == 0 { - f.toRead = dict.readFlush() - f.step = huffmanBytesReader - f.stepState = stateInit - f.b, f.nb = fb, fnb - return - } - goto readLiteral - case v == 256: - f.b, f.nb = fb, fnb - f.finishBlock() - return - // otherwise, reference to older data - case v < 265: - length = v - (257 - 3) - case v < maxNumLit: - val := decCodeToLen[(v - 257)] - length = int(val.length) + 3 - n := uint(val.extra) - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits n>0:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - length += int(fb & bitMask32[n]) - fb >>= n & regSizeMaskUint32 - fnb -= n - default: - if debugDecode { - fmt.Println(v, ">= maxNumLit") - } - f.err = CorruptInputError(f.roffset) - f.b, f.nb = fb, fnb - return - } - - var dist uint32 - if f.hd == nil { - for fnb < 5 { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<5:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - dist = uint32(bits.Reverse8(uint8(fb & 0x1F << 3))) - fb >>= 5 - fnb -= 5 - } else { - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hd.maxRead) - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hd.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hd.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hd.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - dist = uint32(chunk >> huffmanValueShift) - break - } - } - } - - switch { - case dist < 4: - dist++ - case dist < maxNumDist: - nb := uint(dist-2) >> 1 - // have 1 bit in bottom of dist, need nb more. - extra := (dist & 1) << (nb & regSizeMaskUint32) - for fnb < nb { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<nb:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - extra |= fb & bitMask32[nb] - fb >>= nb & regSizeMaskUint32 - fnb -= nb - dist = 1<<((nb+1)®SizeMaskUint32) + 1 + extra - // slower: dist = bitMask32[nb+1] + 2 + extra - default: - f.b, f.nb = fb, fnb - 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 > uint32(dict.histSize()) { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("dist > dict.histSize():", dist, dict.histSize()) - } - f.err = CorruptInputError(f.roffset) - return - } - - f.copyLen, f.copyDist = length, int(dist) - goto copyHistory - } - -copyHistory: - // Perform a backwards copy according to RFC section 3.2.3. - { - cnt := dict.tryWriteCopy(f.copyDist, f.copyLen) - if cnt == 0 { - cnt = dict.writeCopy(f.copyDist, f.copyLen) - } - f.copyLen -= cnt - - if dict.availWrite() == 0 || f.copyLen > 0 { - f.toRead = dict.readFlush() - f.step = huffmanBytesReader // We need to continue this work - f.stepState = stateDict - f.b, f.nb = fb, fnb - return - } - goto readLiteral - } - // Not reached -} - -// Decode a single Huffman block from f. -// hl and hd are the Huffman states for the lit/length values -// and the distance values, respectively. If hd == nil, using the -// fixed distance encoding associated with fixed Huffman blocks. -func (f *decompressor) huffmanBufioReader() { - const ( - stateInit = iota // Zero value must be stateInit - stateDict - ) - fr := f.r.(*bufio.Reader) - - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - fnb, fb, dict := f.nb, f.b, &f.dict - - switch f.stepState { - case stateInit: - goto readLiteral - case stateDict: - goto copyHistory - } - -readLiteral: - // Read literal and/or (length, distance) according to RFC section 3.2.3. - { - var v int - { - // Inlined v, err := f.huffSym(f.hl) - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hl.maxRead) - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hl.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hl.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hl.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - v = int(chunk >> huffmanValueShift) - break - } - } - } - - var length int - switch { - case v < 256: - dict.writeByte(byte(v)) - if dict.availWrite() == 0 { - f.toRead = dict.readFlush() - f.step = huffmanBufioReader - f.stepState = stateInit - f.b, f.nb = fb, fnb - return - } - goto readLiteral - case v == 256: - f.b, f.nb = fb, fnb - f.finishBlock() - return - // otherwise, reference to older data - case v < 265: - length = v - (257 - 3) - case v < maxNumLit: - val := decCodeToLen[(v - 257)] - length = int(val.length) + 3 - n := uint(val.extra) - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits n>0:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - length += int(fb & bitMask32[n]) - fb >>= n & regSizeMaskUint32 - fnb -= n - default: - if debugDecode { - fmt.Println(v, ">= maxNumLit") - } - f.err = CorruptInputError(f.roffset) - f.b, f.nb = fb, fnb - return - } - - var dist uint32 - if f.hd == nil { - for fnb < 5 { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<5:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - dist = uint32(bits.Reverse8(uint8(fb & 0x1F << 3))) - fb >>= 5 - fnb -= 5 - } else { - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hd.maxRead) - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hd.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hd.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hd.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - dist = uint32(chunk >> huffmanValueShift) - break - } - } - } - - switch { - case dist < 4: - dist++ - case dist < maxNumDist: - nb := uint(dist-2) >> 1 - // have 1 bit in bottom of dist, need nb more. - extra := (dist & 1) << (nb & regSizeMaskUint32) - for fnb < nb { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<nb:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - extra |= fb & bitMask32[nb] - fb >>= nb & regSizeMaskUint32 - fnb -= nb - dist = 1<<((nb+1)®SizeMaskUint32) + 1 + extra - // slower: dist = bitMask32[nb+1] + 2 + extra - default: - f.b, f.nb = fb, fnb - 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 > uint32(dict.histSize()) { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("dist > dict.histSize():", dist, dict.histSize()) - } - f.err = CorruptInputError(f.roffset) - return - } - - f.copyLen, f.copyDist = length, int(dist) - goto copyHistory - } - -copyHistory: - // Perform a backwards copy according to RFC section 3.2.3. - { - cnt := dict.tryWriteCopy(f.copyDist, f.copyLen) - if cnt == 0 { - cnt = dict.writeCopy(f.copyDist, f.copyLen) - } - f.copyLen -= cnt - - if dict.availWrite() == 0 || f.copyLen > 0 { - f.toRead = dict.readFlush() - f.step = huffmanBufioReader // We need to continue this work - f.stepState = stateDict - f.b, f.nb = fb, fnb - return - } - goto readLiteral - } - // Not reached -} - -// Decode a single Huffman block from f. -// hl and hd are the Huffman states for the lit/length values -// and the distance values, respectively. If hd == nil, using the -// fixed distance encoding associated with fixed Huffman blocks. -func (f *decompressor) huffmanStringsReader() { - const ( - stateInit = iota // Zero value must be stateInit - stateDict - ) - fr := f.r.(*strings.Reader) - - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - fnb, fb, dict := f.nb, f.b, &f.dict - - switch f.stepState { - case stateInit: - goto readLiteral - case stateDict: - goto copyHistory - } - -readLiteral: - // Read literal and/or (length, distance) according to RFC section 3.2.3. - { - var v int - { - // Inlined v, err := f.huffSym(f.hl) - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hl.maxRead) - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hl.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hl.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hl.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - v = int(chunk >> huffmanValueShift) - break - } - } - } - - var length int - switch { - case v < 256: - dict.writeByte(byte(v)) - if dict.availWrite() == 0 { - f.toRead = dict.readFlush() - f.step = huffmanStringsReader - f.stepState = stateInit - f.b, f.nb = fb, fnb - return - } - goto readLiteral - case v == 256: - f.b, f.nb = fb, fnb - f.finishBlock() - return - // otherwise, reference to older data - case v < 265: - length = v - (257 - 3) - case v < maxNumLit: - val := decCodeToLen[(v - 257)] - length = int(val.length) + 3 - n := uint(val.extra) - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits n>0:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - length += int(fb & bitMask32[n]) - fb >>= n & regSizeMaskUint32 - fnb -= n - default: - if debugDecode { - fmt.Println(v, ">= maxNumLit") - } - f.err = CorruptInputError(f.roffset) - f.b, f.nb = fb, fnb - return - } - - var dist uint32 - if f.hd == nil { - for fnb < 5 { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<5:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - dist = uint32(bits.Reverse8(uint8(fb & 0x1F << 3))) - fb >>= 5 - fnb -= 5 - } else { - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hd.maxRead) - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hd.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hd.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hd.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - dist = uint32(chunk >> huffmanValueShift) - break - } - } - } - - switch { - case dist < 4: - dist++ - case dist < maxNumDist: - nb := uint(dist-2) >> 1 - // have 1 bit in bottom of dist, need nb more. - extra := (dist & 1) << (nb & regSizeMaskUint32) - for fnb < nb { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<nb:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - extra |= fb & bitMask32[nb] - fb >>= nb & regSizeMaskUint32 - fnb -= nb - dist = 1<<((nb+1)®SizeMaskUint32) + 1 + extra - // slower: dist = bitMask32[nb+1] + 2 + extra - default: - f.b, f.nb = fb, fnb - 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 > uint32(dict.histSize()) { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("dist > dict.histSize():", dist, dict.histSize()) - } - f.err = CorruptInputError(f.roffset) - return - } - - f.copyLen, f.copyDist = length, int(dist) - goto copyHistory - } - -copyHistory: - // Perform a backwards copy according to RFC section 3.2.3. - { - cnt := dict.tryWriteCopy(f.copyDist, f.copyLen) - if cnt == 0 { - cnt = dict.writeCopy(f.copyDist, f.copyLen) - } - f.copyLen -= cnt - - if dict.availWrite() == 0 || f.copyLen > 0 { - f.toRead = dict.readFlush() - f.step = huffmanStringsReader // We need to continue this work - f.stepState = stateDict - f.b, f.nb = fb, fnb - return - } - goto readLiteral - } - // Not reached -} - -// Decode a single Huffman block from f. -// hl and hd are the Huffman states for the lit/length values -// and the distance values, respectively. If hd == nil, using the -// fixed distance encoding associated with fixed Huffman blocks. -func (f *decompressor) huffmanGenericReader() { - const ( - stateInit = iota // Zero value must be stateInit - stateDict - ) - fr := f.r.(Reader) - - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - fnb, fb, dict := f.nb, f.b, &f.dict - - switch f.stepState { - case stateInit: - goto readLiteral - case stateDict: - goto copyHistory - } - -readLiteral: - // Read literal and/or (length, distance) according to RFC section 3.2.3. - { - var v int - { - // Inlined v, err := f.huffSym(f.hl) - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hl.maxRead) - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hl.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hl.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hl.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - v = int(chunk >> huffmanValueShift) - break - } - } - } - - var length int - switch { - case v < 256: - dict.writeByte(byte(v)) - if dict.availWrite() == 0 { - f.toRead = dict.readFlush() - f.step = huffmanGenericReader - f.stepState = stateInit - f.b, f.nb = fb, fnb - return - } - goto readLiteral - case v == 256: - f.b, f.nb = fb, fnb - f.finishBlock() - return - // otherwise, reference to older data - case v < 265: - length = v - (257 - 3) - case v < maxNumLit: - val := decCodeToLen[(v - 257)] - length = int(val.length) + 3 - n := uint(val.extra) - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits n>0:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - length += int(fb & bitMask32[n]) - fb >>= n & regSizeMaskUint32 - fnb -= n - default: - if debugDecode { - fmt.Println(v, ">= maxNumLit") - } - f.err = CorruptInputError(f.roffset) - f.b, f.nb = fb, fnb - return - } - - var dist uint32 - if f.hd == nil { - for fnb < 5 { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<5:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - dist = uint32(bits.Reverse8(uint8(fb & 0x1F << 3))) - fb >>= 5 - fnb -= 5 - } else { - // Since a huffmanDecoder can be empty or be composed of a degenerate tree - // with single element, huffSym must error on these two edge cases. In both - // cases, the chunks slice will be 0 for the invalid sequence, leading it - // satisfy the n == 0 check below. - n := uint(f.hd.maxRead) - // Optimization. Compiler isn't smart enough to keep f.b,f.nb in registers, - // but is smart enough to keep local variables in registers, so use nb and b, - // inline call to moreBits and reassign b,nb back to f on return. - for { - for fnb < n { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - f.err = noEOF(err) - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - chunk := f.hd.chunks[fb&(huffmanNumChunks-1)] - n = uint(chunk & huffmanCountMask) - if n > huffmanChunkBits { - chunk = f.hd.links[chunk>>huffmanValueShift][(fb>>huffmanChunkBits)&f.hd.linkMask] - n = uint(chunk & huffmanCountMask) - } - if n <= fnb { - if n == 0 { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("huffsym: n==0") - } - f.err = CorruptInputError(f.roffset) - return - } - fb = fb >> (n & regSizeMaskUint32) - fnb = fnb - n - dist = uint32(chunk >> huffmanValueShift) - break - } - } - } - - switch { - case dist < 4: - dist++ - case dist < maxNumDist: - nb := uint(dist-2) >> 1 - // have 1 bit in bottom of dist, need nb more. - extra := (dist & 1) << (nb & regSizeMaskUint32) - for fnb < nb { - c, err := fr.ReadByte() - if err != nil { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("morebits f.nb<nb:", err) - } - f.err = err - return - } - f.roffset++ - fb |= uint32(c) << (fnb & regSizeMaskUint32) - fnb += 8 - } - extra |= fb & bitMask32[nb] - fb >>= nb & regSizeMaskUint32 - fnb -= nb - dist = 1<<((nb+1)®SizeMaskUint32) + 1 + extra - // slower: dist = bitMask32[nb+1] + 2 + extra - default: - f.b, f.nb = fb, fnb - 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 > uint32(dict.histSize()) { - f.b, f.nb = fb, fnb - if debugDecode { - fmt.Println("dist > dict.histSize():", dist, dict.histSize()) - } - f.err = CorruptInputError(f.roffset) - return - } - - f.copyLen, f.copyDist = length, int(dist) - goto copyHistory - } - -copyHistory: - // Perform a backwards copy according to RFC section 3.2.3. - { - cnt := dict.tryWriteCopy(f.copyDist, f.copyLen) - if cnt == 0 { - cnt = dict.writeCopy(f.copyDist, f.copyLen) - } - f.copyLen -= cnt - - if dict.availWrite() == 0 || f.copyLen > 0 { - f.toRead = dict.readFlush() - f.step = huffmanGenericReader // We need to continue this work - f.stepState = stateDict - f.b, f.nb = fb, fnb - return - } - goto readLiteral - } - // Not reached -} - -func (f *decompressor) huffmanBlockDecoder() { - switch f.r.(type) { - case *bytes.Buffer: - f.huffmanBytesBuffer() - case *bytes.Reader: - f.huffmanBytesReader() - case *bufio.Reader: - f.huffmanBufioReader() - case *strings.Reader: - f.huffmanStringsReader() - case Reader: - f.huffmanGenericReader() - default: - f.huffmanGenericReader() - } -} |