60 lines
2.1 KiB
Go
60 lines
2.1 KiB
Go
// 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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// Encode returns the encoded 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 encoded 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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// Encode handles the Snappy block format, not the Snappy stream format.
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func Encode(dst, src []byte) []byte {
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return s2.EncodeSnappyBetter(dst, src)
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}
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// MaxEncodedLen returns the maximum length of a snappy block, given its
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// uncompressed length.
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//
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// It will return a negative value if srcLen is too large to encode.
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func MaxEncodedLen(srcLen int) int {
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return s2.MaxEncodedLen(srcLen)
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}
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// NewWriter returns a new Writer that compresses to w.
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//
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// The Writer returned does not buffer writes. There is no need to Flush or
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// Close such a Writer.
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//
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// Deprecated: the Writer returned is not suitable for many small writes, only
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// for few large writes. Use NewBufferedWriter instead, which is efficient
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// regardless of the frequency and shape of the writes, and remember to Close
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// that Writer when done.
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func NewWriter(w io.Writer) *Writer {
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return s2.NewWriter(w, s2.WriterSnappyCompat(), s2.WriterBetterCompression(), s2.WriterFlushOnWrite(), s2.WriterConcurrency(1))
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}
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// NewBufferedWriter returns a new Writer that compresses to w, using the
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// framing format described at
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// https://github.com/google/snappy/blob/master/framing_format.txt
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//
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// The Writer returned buffers writes. Users must call Close to guarantee all
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// data has been forwarded to the underlying io.Writer. They may also call
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// Flush zero or more times before calling Close.
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func NewBufferedWriter(w io.Writer) *Writer {
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return s2.NewWriter(w, s2.WriterSnappyCompat(), s2.WriterBetterCompression())
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}
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// Writer is an io.Writer that can write Snappy-compressed bytes.
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//
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// Writer handles the Snappy stream format, not the Snappy block format.
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type Writer = s2.Writer
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