42 lines
687 B
Go
42 lines
687 B
Go
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package buffer
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import (
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"encoding/gob"
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"io"
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"io/ioutil"
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"math"
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)
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type spill struct {
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Buffer
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Spiller io.Writer
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}
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// NewSpill returns a Buffer which writes data to w when there's an error
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// writing to buf. Such as when buf is full, or the disk is full, etc.
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func NewSpill(buf Buffer, w io.Writer) Buffer {
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if w == nil {
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w = ioutil.Discard
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}
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return &spill{
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Buffer: buf,
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Spiller: w,
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}
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}
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func (buf *spill) Cap() int64 {
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return math.MaxInt64
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}
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func (buf *spill) Write(p []byte) (n int, err error) {
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if n, err = buf.Buffer.Write(p); err != nil {
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m, err := buf.Spiller.Write(p[n:])
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return m + n, err
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}
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return len(p), nil
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}
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func init() {
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gob.Register(&spill{})
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}
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