diff options
Diffstat (limited to 'vendor/github.com/klauspost/compress/zstd/encoder_options.go')
-rw-r--r-- | vendor/github.com/klauspost/compress/zstd/encoder_options.go | 38 |
1 files changed, 30 insertions, 8 deletions
diff --git a/vendor/github.com/klauspost/compress/zstd/encoder_options.go b/vendor/github.com/klauspost/compress/zstd/encoder_options.go index 44d8dbd1..8e15be2f 100644 --- a/vendor/github.com/klauspost/compress/zstd/encoder_options.go +++ b/vendor/github.com/klauspost/compress/zstd/encoder_options.go @@ -3,6 +3,8 @@ package zstd import ( "errors" "fmt" + "math" + "math/bits" "runtime" "strings" ) @@ -47,22 +49,22 @@ func (o encoderOptions) encoder() encoder { switch o.level { case SpeedFastest: if o.dict != nil { - return &fastEncoderDict{fastEncoder: fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), lowMem: o.lowMem}}} + return &fastEncoderDict{fastEncoder: fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), bufferReset: math.MaxInt32 - int32(o.windowSize*2), lowMem: o.lowMem}}} } - return &fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), lowMem: o.lowMem}} + return &fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), bufferReset: math.MaxInt32 - int32(o.windowSize*2), lowMem: o.lowMem}} case SpeedDefault: if o.dict != nil { - return &doubleFastEncoderDict{fastEncoderDict: fastEncoderDict{fastEncoder: fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), lowMem: o.lowMem}}}} + return &doubleFastEncoderDict{fastEncoderDict: fastEncoderDict{fastEncoder: fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), bufferReset: math.MaxInt32 - int32(o.windowSize*2), lowMem: o.lowMem}}}} } - return &doubleFastEncoder{fastEncoder: fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), lowMem: o.lowMem}}} + return &doubleFastEncoder{fastEncoder: fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), bufferReset: math.MaxInt32 - int32(o.windowSize*2), lowMem: o.lowMem}}} case SpeedBetterCompression: if o.dict != nil { - return &betterFastEncoderDict{betterFastEncoder: betterFastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), lowMem: o.lowMem}}} + return &betterFastEncoderDict{betterFastEncoder: betterFastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), bufferReset: math.MaxInt32 - int32(o.windowSize*2), lowMem: o.lowMem}}} } - return &betterFastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), lowMem: o.lowMem}} + return &betterFastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), bufferReset: math.MaxInt32 - int32(o.windowSize*2), lowMem: o.lowMem}} case SpeedBestCompression: - return &bestFastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), lowMem: o.lowMem}} + return &bestFastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize), bufferReset: math.MaxInt32 - int32(o.windowSize*2), lowMem: o.lowMem}} } panic("unknown compression level") } @@ -283,7 +285,7 @@ func WithNoEntropyCompression(b bool) EOption { // a decoder is allowed to reject a compressed frame which requests a memory size beyond decoder's authorized range. // For broader compatibility, decoders are recommended to support memory sizes of at least 8 MB. // This is only a recommendation, each decoder is free to support higher or lower limits, depending on local limitations. -// If this is not specified, block encodes will automatically choose this based on the input size. +// If this is not specified, block encodes will automatically choose this based on the input size and the window size. // This setting has no effect on streamed encodes. func WithSingleSegment(b bool) EOption { return func(o *encoderOptions) error { @@ -304,7 +306,13 @@ func WithLowerEncoderMem(b bool) EOption { } // WithEncoderDict allows to register a dictionary that will be used for the encode. +// +// The slice dict must be in the [dictionary format] produced by +// "zstd --train" from the Zstandard reference implementation. +// // The encoder *may* choose to use no dictionary instead for certain payloads. +// +// [dictionary format]: https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#dictionary-format func WithEncoderDict(dict []byte) EOption { return func(o *encoderOptions) error { d, err := loadDict(dict) @@ -315,3 +323,17 @@ func WithEncoderDict(dict []byte) EOption { return nil } } + +// WithEncoderDictRaw registers a dictionary that may be used by the encoder. +// +// The slice content may contain arbitrary data. It will be used as an initial +// history. +func WithEncoderDictRaw(id uint32, content []byte) EOption { + return func(o *encoderOptions) error { + if bits.UintSize > 32 && uint(len(content)) > dictMaxLength { + return fmt.Errorf("dictionary of size %d > 2GiB too large", len(content)) + } + o.dict = &dict{id: id, content: content, offsets: [3]int{1, 4, 8}} + return nil + } +} |