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-rw-r--r--vendor/github.com/klauspost/compress/huff0/bitwriter.go13
-rw-r--r--vendor/github.com/klauspost/compress/huff0/compress.go10
-rw-r--r--vendor/github.com/klauspost/compress/huff0/decompress.go24
-rw-r--r--vendor/github.com/klauspost/compress/huff0/huff0.go3
4 files changed, 45 insertions, 5 deletions
diff --git a/vendor/github.com/klauspost/compress/huff0/bitwriter.go b/vendor/github.com/klauspost/compress/huff0/bitwriter.go
index bda4021ef..6bce4e87d 100644
--- a/vendor/github.com/klauspost/compress/huff0/bitwriter.go
+++ b/vendor/github.com/klauspost/compress/huff0/bitwriter.go
@@ -43,6 +43,11 @@ func (b *bitWriter) addBits16Clean(value uint16, bits uint8) {
func (b *bitWriter) encSymbol(ct cTable, symbol byte) {
enc := ct[symbol]
b.bitContainer |= uint64(enc.val) << (b.nBits & 63)
+ if false {
+ if enc.nBits == 0 {
+ panic("nbits 0")
+ }
+ }
b.nBits += enc.nBits
}
@@ -54,6 +59,14 @@ func (b *bitWriter) encTwoSymbols(ct cTable, av, bv byte) {
sh := b.nBits & 63
combined := uint64(encA.val) | (uint64(encB.val) << (encA.nBits & 63))
b.bitContainer |= combined << sh
+ if false {
+ if encA.nBits == 0 {
+ panic("nbitsA 0")
+ }
+ if encB.nBits == 0 {
+ panic("nbitsB 0")
+ }
+ }
b.nBits += encA.nBits + encB.nBits
}
diff --git a/vendor/github.com/klauspost/compress/huff0/compress.go b/vendor/github.com/klauspost/compress/huff0/compress.go
index 0843cb014..f9ed5f830 100644
--- a/vendor/github.com/klauspost/compress/huff0/compress.go
+++ b/vendor/github.com/klauspost/compress/huff0/compress.go
@@ -77,8 +77,11 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
// Each symbol present maximum once or too well distributed.
return nil, false, ErrIncompressible
}
-
- if s.Reuse == ReusePolicyPrefer && canReuse {
+ if s.Reuse == ReusePolicyMust && !canReuse {
+ // We must reuse, but we can't.
+ return nil, false, ErrIncompressible
+ }
+ if (s.Reuse == ReusePolicyPrefer || s.Reuse == ReusePolicyMust) && canReuse {
keepTable := s.cTable
keepTL := s.actualTableLog
s.cTable = s.prevTable
@@ -90,6 +93,9 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
s.OutData = s.Out
return s.Out, true, nil
}
+ if s.Reuse == ReusePolicyMust {
+ return nil, false, ErrIncompressible
+ }
// Do not attempt to re-use later.
s.prevTable = s.prevTable[:0]
}
diff --git a/vendor/github.com/klauspost/compress/huff0/decompress.go b/vendor/github.com/klauspost/compress/huff0/decompress.go
index a03b2634a..41703bba4 100644
--- a/vendor/github.com/klauspost/compress/huff0/decompress.go
+++ b/vendor/github.com/klauspost/compress/huff0/decompress.go
@@ -32,7 +32,7 @@ const use8BitTables = true
// The size of the input may be larger than the table definition.
// Any content remaining after the table definition will be returned.
// If no Scratch is provided a new one is allocated.
-// The returned Scratch can be used for decoding input using this table.
+// The returned Scratch can be used for encoding or decoding input using this table.
func ReadTable(in []byte, s *Scratch) (s2 *Scratch, remain []byte, err error) {
s, err = s.prepare(in)
if err != nil {
@@ -58,8 +58,8 @@ func ReadTable(in []byte, s *Scratch) (s2 *Scratch, remain []byte, err error) {
s.symbolLen = uint16(oSize)
in = in[iSize:]
} else {
- if len(in) <= int(iSize) {
- return s, nil, errors.New("input too small for table")
+ if len(in) < int(iSize) {
+ return s, nil, fmt.Errorf("input too small for table, want %d bytes, have %d", iSize, len(in))
}
// FSE compressed weights
s.fse.DecompressLimit = 255
@@ -138,15 +138,33 @@ func ReadTable(in []byte, s *Scratch) (s2 *Scratch, remain []byte, err error) {
if len(s.dt.single) != tSize {
s.dt.single = make([]dEntrySingle, tSize)
}
+ cTable := s.prevTable
+ if cap(cTable) < maxSymbolValue+1 {
+ cTable = make([]cTableEntry, 0, maxSymbolValue+1)
+ }
+ cTable = cTable[:maxSymbolValue+1]
+ s.prevTable = cTable[:s.symbolLen]
+ s.prevTableLog = s.actualTableLog
+
for n, w := range s.huffWeight[:s.symbolLen] {
if w == 0 {
+ cTable[n] = cTableEntry{
+ val: 0,
+ nBits: 0,
+ }
continue
}
length := (uint32(1) << w) >> 1
d := dEntrySingle{
entry: uint16(s.actualTableLog+1-w) | (uint16(n) << 8),
}
+
rank := &rankStats[w]
+ cTable[n] = cTableEntry{
+ val: uint16(*rank >> (w - 1)),
+ nBits: uint8(d.entry),
+ }
+
single := s.dt.single[*rank : *rank+length]
for i := range single {
single[i] = d
diff --git a/vendor/github.com/klauspost/compress/huff0/huff0.go b/vendor/github.com/klauspost/compress/huff0/huff0.go
index 177d6c4ea..5dd66854b 100644
--- a/vendor/github.com/klauspost/compress/huff0/huff0.go
+++ b/vendor/github.com/klauspost/compress/huff0/huff0.go
@@ -55,6 +55,9 @@ const (
// ReusePolicyNone will disable re-use of tables.
// This is slightly faster than ReusePolicyAllow but may produce larger output.
ReusePolicyNone
+
+ // ReusePolicyMust must allow reuse and produce smaller output.
+ ReusePolicyMust
)
type Scratch struct {