31 lines
632 B
Go
31 lines
632 B
Go
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// Copyright (C) 2018 Storj Labs, Inc.
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// See LICENSE for copying information.
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package utils
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// ReaderSource takes a src func and turns it into an io.Reader
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type ReaderSource struct {
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src func() ([]byte, error)
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buf []byte
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err error
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}
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// NewReaderSource makes a new ReaderSource
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func NewReaderSource(src func() ([]byte, error)) *ReaderSource {
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return &ReaderSource{src: src}
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}
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// Read implements io.Reader
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func (rs *ReaderSource) Read(p []byte) (n int, err error) {
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if rs.err != nil {
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return 0, rs.err
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}
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if len(rs.buf) == 0 {
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rs.buf, rs.err = rs.src()
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}
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n = copy(p, rs.buf)
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rs.buf = rs.buf[n:]
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return n, rs.err
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}
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