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-rw-r--r--vendor/github.com/klauspost/compress/zstd/blockenc.go33
1 files changed, 21 insertions, 12 deletions
diff --git a/vendor/github.com/klauspost/compress/zstd/blockenc.go b/vendor/github.com/klauspost/compress/zstd/blockenc.go
index 99eccda11..507757d52 100644
--- a/vendor/github.com/klauspost/compress/zstd/blockenc.go
+++ b/vendor/github.com/klauspost/compress/zstd/blockenc.go
@@ -299,6 +299,20 @@ func (b *blockEnc) encodeRaw(a []byte) {
}
}
+// encodeRaw can be used to set the output to a raw representation of supplied bytes.
+func (b *blockEnc) encodeRawTo(dst, src []byte) []byte {
+ var bh blockHeader
+ bh.setLast(b.last)
+ bh.setSize(uint32(len(src)))
+ bh.setType(blockTypeRaw)
+ dst = bh.appendTo(dst)
+ dst = append(dst, src...)
+ if debug {
+ println("Adding RAW block, length", len(src))
+ }
+ return dst
+}
+
// encodeLits can be used if the block is only litLen.
func (b *blockEnc) encodeLits(raw bool) error {
var bh blockHeader
@@ -324,18 +338,10 @@ func (b *blockEnc) encodeLits(raw bool) error {
if len(b.literals) >= 1024 {
// Use 4 Streams.
out, reUsed, err = huff0.Compress4X(b.literals, b.litEnc)
- if len(out) > len(b.literals)-len(b.literals)>>4 {
- // Bail out of compression is too little.
- err = huff0.ErrIncompressible
- }
} else if len(b.literals) > 32 {
// Use 1 stream
single = true
out, reUsed, err = huff0.Compress1X(b.literals, b.litEnc)
- if len(out) > len(b.literals)-len(b.literals)>>4 {
- // Bail out of compression is too little.
- err = huff0.ErrIncompressible
- }
} else {
err = huff0.ErrIncompressible
}
@@ -437,7 +443,7 @@ func fuzzFseEncoder(data []byte) int {
return 1
}
-// encode will encode the block and put the output in b.output.
+// encode will encode the block and append the output in b.output.
func (b *blockEnc) encode(raw bool) error {
if len(b.sequences) == 0 {
return b.encodeLits(raw)
@@ -451,6 +457,8 @@ func (b *blockEnc) encode(raw bool) error {
var lh literalsHeader
bh.setLast(b.last)
bh.setType(blockTypeCompressed)
+ // Store offset of the block header. Needed when we know the size.
+ bhOffset := len(b.output)
b.output = bh.appendTo(b.output)
var (
@@ -468,6 +476,7 @@ func (b *blockEnc) encode(raw bool) error {
} else {
err = huff0.ErrIncompressible
}
+
switch err {
case huff0.ErrIncompressible:
lh.setType(literalsBlockRaw)
@@ -735,18 +744,18 @@ func (b *blockEnc) encode(raw bool) error {
}
b.output = wr.out
- if len(b.output)-3 >= b.size {
+ if len(b.output)-3-bhOffset >= b.size {
// Maybe even add a bigger margin.
b.litEnc.Reuse = huff0.ReusePolicyNone
return errIncompressible
}
// Size is output minus block header.
- bh.setSize(uint32(len(b.output)) - 3)
+ bh.setSize(uint32(len(b.output)-bhOffset) - 3)
if debug {
println("Rewriting block header", bh)
}
- _ = bh.appendTo(b.output[:0])
+ _ = bh.appendTo(b.output[bhOffset:bhOffset])
b.coders.setPrev(llEnc, mlEnc, ofEnc)
return nil
}