diff options
Diffstat (limited to 'vendor/github.com/klauspost/compress/zstd/decoder_options.go')
| -rw-r--r-- | vendor/github.com/klauspost/compress/zstd/decoder_options.go | 169 |
1 files changed, 0 insertions, 169 deletions
diff --git a/vendor/github.com/klauspost/compress/zstd/decoder_options.go b/vendor/github.com/klauspost/compress/zstd/decoder_options.go deleted file mode 100644 index 774c5f00f..000000000 --- a/vendor/github.com/klauspost/compress/zstd/decoder_options.go +++ /dev/null @@ -1,169 +0,0 @@ -// Copyright 2019+ Klaus Post. All rights reserved. -// License information can be found in the LICENSE file. -// Based on work by Yann Collet, released under BSD License. - -package zstd - -import ( - "errors" - "fmt" - "math/bits" - "runtime" -) - -// DOption is an option for creating a decoder. -type DOption func(*decoderOptions) error - -// options retains accumulated state of multiple options. -type decoderOptions struct { - lowMem bool - concurrent int - maxDecodedSize uint64 - maxWindowSize uint64 - dicts []*dict - ignoreChecksum bool - limitToCap bool - decodeBufsBelow int -} - -func (o *decoderOptions) setDefault() { - *o = decoderOptions{ - // use less ram: true for now, but may change. - lowMem: true, - concurrent: runtime.GOMAXPROCS(0), - maxWindowSize: MaxWindowSize, - decodeBufsBelow: 128 << 10, - } - if o.concurrent > 4 { - o.concurrent = 4 - } - o.maxDecodedSize = 64 << 30 -} - -// WithDecoderLowmem will set whether to use a lower amount of memory, -// but possibly have to allocate more while running. -func WithDecoderLowmem(b bool) DOption { - return func(o *decoderOptions) error { o.lowMem = b; return nil } -} - -// WithDecoderConcurrency sets the number of created decoders. -// When decoding block with DecodeAll, this will limit the number -// of possible concurrently running decodes. -// When decoding streams, this will limit the number of -// inflight blocks. -// When decoding streams and setting maximum to 1, -// no async decoding will be done. -// When a value of 0 is provided GOMAXPROCS will be used. -// By default this will be set to 4 or GOMAXPROCS, whatever is lower. -func WithDecoderConcurrency(n int) DOption { - return func(o *decoderOptions) error { - if n < 0 { - return errors.New("concurrency must be at least 1") - } - if n == 0 { - o.concurrent = runtime.GOMAXPROCS(0) - } else { - o.concurrent = n - } - return nil - } -} - -// WithDecoderMaxMemory allows to set a maximum decoded size for in-memory -// non-streaming operations or maximum window size for streaming operations. -// This can be used to control memory usage of potentially hostile content. -// Maximum is 1 << 63 bytes. Default is 64GiB. -func WithDecoderMaxMemory(n uint64) DOption { - return func(o *decoderOptions) error { - if n == 0 { - return errors.New("WithDecoderMaxMemory must be at least 1") - } - if n > 1<<63 { - return errors.New("WithDecoderMaxmemory must be less than 1 << 63") - } - o.maxDecodedSize = n - return nil - } -} - -// WithDecoderDicts allows to register one or more dictionaries for the decoder. -// -// Each slice in dict must be in the [dictionary format] produced by -// "zstd --train" from the Zstandard reference implementation. -// -// If several dictionaries with the same ID are provided, the last one will be used. -// -// [dictionary format]: https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#dictionary-format -func WithDecoderDicts(dicts ...[]byte) DOption { - return func(o *decoderOptions) error { - for _, b := range dicts { - d, err := loadDict(b) - if err != nil { - return err - } - o.dicts = append(o.dicts, d) - } - return nil - } -} - -// WithDecoderDictRaw registers a dictionary that may be used by the decoder. -// The slice content can be arbitrary data. -func WithDecoderDictRaw(id uint32, content []byte) DOption { - return func(o *decoderOptions) error { - if bits.UintSize > 32 && uint(len(content)) > dictMaxLength { - return fmt.Errorf("dictionary of size %d > 2GiB too large", len(content)) - } - o.dicts = append(o.dicts, &dict{id: id, content: content, offsets: [3]int{1, 4, 8}}) - return nil - } -} - -// WithDecoderMaxWindow allows to set a maximum window size for decodes. -// This allows rejecting packets that will cause big memory usage. -// The Decoder will likely allocate more memory based on the WithDecoderLowmem setting. -// If WithDecoderMaxMemory is set to a lower value, that will be used. -// Default is 512MB, Maximum is ~3.75 TB as per zstandard spec. -func WithDecoderMaxWindow(size uint64) DOption { - return func(o *decoderOptions) error { - if size < MinWindowSize { - return errors.New("WithMaxWindowSize must be at least 1KB, 1024 bytes") - } - if size > (1<<41)+7*(1<<38) { - return errors.New("WithMaxWindowSize must be less than (1<<41) + 7*(1<<38) ~ 3.75TB") - } - o.maxWindowSize = size - return nil - } -} - -// WithDecodeAllCapLimit will limit DecodeAll to decoding cap(dst)-len(dst) bytes, -// or any size set in WithDecoderMaxMemory. -// This can be used to limit decoding to a specific maximum output size. -// Disabled by default. -func WithDecodeAllCapLimit(b bool) DOption { - return func(o *decoderOptions) error { - o.limitToCap = b - return nil - } -} - -// WithDecodeBuffersBelow will fully decode readers that have a -// `Bytes() []byte` and `Len() int` interface similar to bytes.Buffer. -// This typically uses less allocations but will have the full decompressed object in memory. -// Note that DecodeAllCapLimit will disable this, as well as giving a size of 0 or less. -// Default is 128KiB. -func WithDecodeBuffersBelow(size int) DOption { - return func(o *decoderOptions) error { - o.decodeBufsBelow = size - return nil - } -} - -// IgnoreChecksum allows to forcibly ignore checksum checking. -func IgnoreChecksum(b bool) DOption { - return func(o *decoderOptions) error { - o.ignoreChecksum = b - return nil - } -} |