diff options
Diffstat (limited to 'vendor/github.com/klauspost/compress/huff0/decompress_generic.go')
| -rw-r--r-- | vendor/github.com/klauspost/compress/huff0/decompress_generic.go | 299 |
1 files changed, 0 insertions, 299 deletions
diff --git a/vendor/github.com/klauspost/compress/huff0/decompress_generic.go b/vendor/github.com/klauspost/compress/huff0/decompress_generic.go deleted file mode 100644 index 908c17de6..000000000 --- a/vendor/github.com/klauspost/compress/huff0/decompress_generic.go +++ /dev/null @@ -1,299 +0,0 @@ -//go:build !amd64 || appengine || !gc || noasm -// +build !amd64 appengine !gc noasm - -// This file contains a generic implementation of Decoder.Decompress4X. -package huff0 - -import ( - "errors" - "fmt" -) - -// Decompress4X will decompress a 4X encoded stream. -// The length of the supplied input must match the end of a block exactly. -// The *capacity* of the dst slice must match the destination size of -// the uncompressed data exactly. -func (d *Decoder) Decompress4X(dst, src []byte) ([]byte, error) { - if len(d.dt.single) == 0 { - return nil, errors.New("no table loaded") - } - if len(src) < 6+(4*1) { - return nil, errors.New("input too small") - } - if use8BitTables && d.actualTableLog <= 8 { - return d.decompress4X8bit(dst, src) - } - - var br [4]bitReaderShifted - // Decode "jump table" - start := 6 - for i := 0; i < 3; i++ { - length := int(src[i*2]) | (int(src[i*2+1]) << 8) - if start+length >= len(src) { - return nil, errors.New("truncated input (or invalid offset)") - } - err := br[i].init(src[start : start+length]) - if err != nil { - return nil, err - } - start += length - } - err := br[3].init(src[start:]) - if err != nil { - return nil, err - } - - // destination, offset to match first output - dstSize := cap(dst) - dst = dst[:dstSize] - out := dst - dstEvery := (dstSize + 3) / 4 - - const tlSize = 1 << tableLogMax - const tlMask = tlSize - 1 - single := d.dt.single[:tlSize] - - // Use temp table to avoid bound checks/append penalty. - buf := d.buffer() - var off uint8 - var decoded int - - // Decode 2 values from each decoder/loop. - const bufoff = 256 - for { - if br[0].off < 4 || br[1].off < 4 || br[2].off < 4 || br[3].off < 4 { - break - } - - { - const stream = 0 - const stream2 = 1 - br[stream].fillFast() - br[stream2].fillFast() - - val := br[stream].peekBitsFast(d.actualTableLog) - val2 := br[stream2].peekBitsFast(d.actualTableLog) - v := single[val&tlMask] - v2 := single[val2&tlMask] - br[stream].advance(uint8(v.entry)) - br[stream2].advance(uint8(v2.entry)) - buf[stream][off] = uint8(v.entry >> 8) - buf[stream2][off] = uint8(v2.entry >> 8) - - val = br[stream].peekBitsFast(d.actualTableLog) - val2 = br[stream2].peekBitsFast(d.actualTableLog) - v = single[val&tlMask] - v2 = single[val2&tlMask] - br[stream].advance(uint8(v.entry)) - br[stream2].advance(uint8(v2.entry)) - buf[stream][off+1] = uint8(v.entry >> 8) - buf[stream2][off+1] = uint8(v2.entry >> 8) - } - - { - const stream = 2 - const stream2 = 3 - br[stream].fillFast() - br[stream2].fillFast() - - val := br[stream].peekBitsFast(d.actualTableLog) - val2 := br[stream2].peekBitsFast(d.actualTableLog) - v := single[val&tlMask] - v2 := single[val2&tlMask] - br[stream].advance(uint8(v.entry)) - br[stream2].advance(uint8(v2.entry)) - buf[stream][off] = uint8(v.entry >> 8) - buf[stream2][off] = uint8(v2.entry >> 8) - - val = br[stream].peekBitsFast(d.actualTableLog) - val2 = br[stream2].peekBitsFast(d.actualTableLog) - v = single[val&tlMask] - v2 = single[val2&tlMask] - br[stream].advance(uint8(v.entry)) - br[stream2].advance(uint8(v2.entry)) - buf[stream][off+1] = uint8(v.entry >> 8) - buf[stream2][off+1] = uint8(v2.entry >> 8) - } - - off += 2 - - if off == 0 { - if bufoff > dstEvery { - d.bufs.Put(buf) - return nil, errors.New("corruption detected: stream overrun 1") - } - // There must at least be 3 buffers left. - if len(out)-bufoff < dstEvery*3 { - d.bufs.Put(buf) - return nil, errors.New("corruption detected: stream overrun 2") - } - //copy(out, buf[0][:]) - //copy(out[dstEvery:], buf[1][:]) - //copy(out[dstEvery*2:], buf[2][:]) - //copy(out[dstEvery*3:], buf[3][:]) - *(*[bufoff]byte)(out) = buf[0] - *(*[bufoff]byte)(out[dstEvery:]) = buf[1] - *(*[bufoff]byte)(out[dstEvery*2:]) = buf[2] - *(*[bufoff]byte)(out[dstEvery*3:]) = buf[3] - out = out[bufoff:] - decoded += bufoff * 4 - } - } - if off > 0 { - ioff := int(off) - if len(out) < dstEvery*3+ioff { - d.bufs.Put(buf) - return nil, errors.New("corruption detected: stream overrun 3") - } - copy(out, buf[0][:off]) - copy(out[dstEvery:], buf[1][:off]) - copy(out[dstEvery*2:], buf[2][:off]) - copy(out[dstEvery*3:], buf[3][:off]) - decoded += int(off) * 4 - out = out[off:] - } - - // Decode remaining. - remainBytes := dstEvery - (decoded / 4) - for i := range br { - offset := dstEvery * i - endsAt := offset + remainBytes - if endsAt > len(out) { - endsAt = len(out) - } - br := &br[i] - bitsLeft := br.remaining() - for bitsLeft > 0 { - br.fill() - if offset >= endsAt { - d.bufs.Put(buf) - return nil, errors.New("corruption detected: stream overrun 4") - } - - // Read value and increment offset. - val := br.peekBitsFast(d.actualTableLog) - v := single[val&tlMask].entry - nBits := uint8(v) - br.advance(nBits) - bitsLeft -= uint(nBits) - out[offset] = uint8(v >> 8) - offset++ - } - if offset != endsAt { - d.bufs.Put(buf) - return nil, fmt.Errorf("corruption detected: short output block %d, end %d != %d", i, offset, endsAt) - } - decoded += offset - dstEvery*i - err = br.close() - if err != nil { - return nil, err - } - } - d.bufs.Put(buf) - if dstSize != decoded { - return nil, errors.New("corruption detected: short output block") - } - return dst, nil -} - -// Decompress1X will decompress a 1X encoded stream. -// The cap of the output buffer will be the maximum decompressed size. -// The length of the supplied input must match the end of a block exactly. -func (d *Decoder) Decompress1X(dst, src []byte) ([]byte, error) { - if len(d.dt.single) == 0 { - return nil, errors.New("no table loaded") - } - if use8BitTables && d.actualTableLog <= 8 { - return d.decompress1X8Bit(dst, src) - } - var br bitReaderShifted - err := br.init(src) - if err != nil { - return dst, err - } - maxDecodedSize := cap(dst) - dst = dst[:0] - - // Avoid bounds check by always having full sized table. - const tlSize = 1 << tableLogMax - const tlMask = tlSize - 1 - dt := d.dt.single[:tlSize] - - // Use temp table to avoid bound checks/append penalty. - bufs := d.buffer() - buf := &bufs[0] - var off uint8 - - for br.off >= 8 { - br.fillFast() - v := dt[br.peekBitsFast(d.actualTableLog)&tlMask] - br.advance(uint8(v.entry)) - buf[off+0] = uint8(v.entry >> 8) - - v = dt[br.peekBitsFast(d.actualTableLog)&tlMask] - br.advance(uint8(v.entry)) - buf[off+1] = uint8(v.entry >> 8) - - // Refill - br.fillFast() - - v = dt[br.peekBitsFast(d.actualTableLog)&tlMask] - br.advance(uint8(v.entry)) - buf[off+2] = uint8(v.entry >> 8) - - v = dt[br.peekBitsFast(d.actualTableLog)&tlMask] - br.advance(uint8(v.entry)) - buf[off+3] = uint8(v.entry >> 8) - - off += 4 - if off == 0 { - if len(dst)+256 > maxDecodedSize { - br.close() - d.bufs.Put(bufs) - return nil, ErrMaxDecodedSizeExceeded - } - dst = append(dst, buf[:]...) - } - } - - if len(dst)+int(off) > maxDecodedSize { - d.bufs.Put(bufs) - br.close() - return nil, ErrMaxDecodedSizeExceeded - } - dst = append(dst, buf[:off]...) - - // br < 8, so uint8 is fine - bitsLeft := uint8(br.off)*8 + 64 - br.bitsRead - for bitsLeft > 0 { - br.fill() - if false && br.bitsRead >= 32 { - if br.off >= 4 { - v := br.in[br.off-4:] - v = v[:4] - low := (uint32(v[0])) | (uint32(v[1]) << 8) | (uint32(v[2]) << 16) | (uint32(v[3]) << 24) - br.value = (br.value << 32) | uint64(low) - br.bitsRead -= 32 - br.off -= 4 - } else { - for br.off > 0 { - br.value = (br.value << 8) | uint64(br.in[br.off-1]) - br.bitsRead -= 8 - br.off-- - } - } - } - if len(dst) >= maxDecodedSize { - d.bufs.Put(bufs) - br.close() - return nil, ErrMaxDecodedSizeExceeded - } - v := d.dt.single[br.peekBitsFast(d.actualTableLog)&tlMask] - nBits := uint8(v.entry) - br.advance(nBits) - bitsLeft -= nBits - dst = append(dst, uint8(v.entry>>8)) - } - d.bufs.Put(bufs) - return dst, br.close() -} |