61 lines
1.9 KiB
Go
61 lines
1.9 KiB
Go
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// Copyright 2011 The Snappy-Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package snappy
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import (
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"io"
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"github.com/klauspost/compress/s2"
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)
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var (
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// ErrCorrupt reports that the input is invalid.
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ErrCorrupt = s2.ErrCorrupt
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// ErrTooLarge reports that the uncompressed length is too large.
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ErrTooLarge = s2.ErrTooLarge
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// ErrUnsupported reports that the input isn't supported.
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ErrUnsupported = s2.ErrUnsupported
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)
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const (
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// maxBlockSize is the maximum size of the input to encodeBlock. It is not
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// part of the wire format per se, but some parts of the encoder assume
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// that an offset fits into a uint16.
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//
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// Also, for the framing format (Writer type instead of Encode function),
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// https://github.com/google/snappy/blob/master/framing_format.txt says
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// that "the uncompressed data in a chunk must be no longer than 65536
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// bytes".
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maxBlockSize = 65536
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)
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// DecodedLen returns the length of the decoded block.
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func DecodedLen(src []byte) (int, error) {
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return s2.DecodedLen(src)
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}
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// Decode returns the decoded form of src. The returned slice may be a sub-
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// slice of dst if dst was large enough to hold the entire decoded block.
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// Otherwise, a newly allocated slice will be returned.
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//
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// The dst and src must not overlap. It is valid to pass a nil dst.
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//
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// Decode handles the Snappy block format, not the Snappy stream format.
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func Decode(dst, src []byte) ([]byte, error) {
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return s2.Decode(dst, src)
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}
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// NewReader returns a new Reader that decompresses from r, using the framing
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// format described at
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// https://github.com/google/snappy/blob/master/framing_format.txt
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func NewReader(r io.Reader) *Reader {
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return s2.NewReader(r, s2.ReaderMaxBlockSize(maxBlockSize))
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}
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// Reader is an io.Reader that can read Snappy-compressed bytes.
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//
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// Reader handles the Snappy stream format, not the Snappy block format.
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type Reader = s2.Reader
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