29 lines
716 B
Go
29 lines
716 B
Go
package readers
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import "io"
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// NewCountingReader returns a CountingReader, which will read from the given
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// reader while keeping track of how many bytes were read.
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func NewCountingReader(in io.Reader) *CountingReader {
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return &CountingReader{in: in}
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}
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// CountingReader holds a reader and a read count of how many bytes were read
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// so far.
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type CountingReader struct {
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in io.Reader
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read uint64
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}
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// Read reads from the underlying reader.
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func (cr *CountingReader) Read(b []byte) (int, error) {
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n, err := cr.in.Read(b)
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cr.read += uint64(n)
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return n, err
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}
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// BytesRead returns how many bytes were read from the underlying reader so far.
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func (cr *CountingReader) BytesRead() uint64 {
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return cr.read
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}
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