61 lines
1.4 KiB
Go
61 lines
1.4 KiB
Go
// Copyright 2010 The 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 io
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import "os"
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type multiReader struct {
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readers []Reader
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}
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func (mr *multiReader) Read(p []byte) (n int, err os.Error) {
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for len(mr.readers) > 0 {
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n, err = mr.readers[0].Read(p)
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if n > 0 || err != os.EOF {
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if err == os.EOF {
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// This shouldn't happen.
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// Well-behaved Readers should never
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// return non-zero bytes read with an
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// EOF. But if so, we clean it.
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err = nil
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}
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return
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}
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mr.readers = mr.readers[1:]
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}
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return 0, os.EOF
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}
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// MultiReader returns a Reader that's the logical concatenation of
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// the provided input readers. They're read sequentially. Once all
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// inputs are drained, Read will return os.EOF.
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func MultiReader(readers ...Reader) Reader {
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return &multiReader{readers}
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}
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type multiWriter struct {
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writers []Writer
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}
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func (t *multiWriter) Write(p []byte) (n int, err os.Error) {
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for _, w := range t.writers {
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n, err = w.Write(p)
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if err != nil {
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return
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}
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if n != len(p) {
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err = ErrShortWrite
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return
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}
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}
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return len(p), nil
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}
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// MultiWriter creates a writer that duplicates its writes to all the
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// provided writers, similar to the Unix tee(1) command.
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func MultiWriter(writers ...Writer) Writer {
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return &multiWriter{writers}
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}
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