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Creates a `fixedBuffer` type that is used to encapsulate functionality for reading/writing from the underlying byte slices. Uses lazily-loaded set of sync.Pools for storing buffers that are no longer needed so they can be re-used. ``` benchmark old ns/op new ns/op delta BenchmarkBytesPipeWrite-8 138469 48985 -64.62% BenchmarkBytesPipeRead-8 130922 56601 -56.77% benchmark old allocs new allocs delta BenchmarkBytesPipeWrite-8 18 8 -55.56% BenchmarkBytesPipeRead-8 0 0 +0.00% benchmark old bytes new bytes delta BenchmarkBytesPipeWrite-8 66903 1649 -97.54% BenchmarkBytesPipeRead-8 0 1 +Inf% ``` Signed-off-by: Brian Goff <cpuguy83@gmail.com>
51 lines
808 B
Go
51 lines
808 B
Go
package ioutils
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import (
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"errors"
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"io"
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)
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var errBufferFull = errors.New("buffer is full")
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type fixedBuffer struct {
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buf []byte
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pos int
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lastRead int
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}
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func (b *fixedBuffer) Write(p []byte) (int, error) {
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n := copy(b.buf[b.pos:cap(b.buf)], p)
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b.pos += n
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if n < len(p) {
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if b.pos == cap(b.buf) {
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return n, errBufferFull
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}
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return n, io.ErrShortWrite
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}
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return n, nil
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}
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func (b *fixedBuffer) Read(p []byte) (int, error) {
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n := copy(p, b.buf[b.lastRead:b.pos])
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b.lastRead += n
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return n, nil
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}
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func (b *fixedBuffer) Len() int {
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return b.pos - b.lastRead
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}
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func (b *fixedBuffer) Cap() int {
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return cap(b.buf)
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}
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func (b *fixedBuffer) Reset() {
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b.pos = 0
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b.lastRead = 0
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b.buf = b.buf[:0]
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}
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func (b *fixedBuffer) String() string {
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return string(b.buf[b.lastRead:b.pos])
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}
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