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41 lines
785 B
Go
41 lines
785 B
Go
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// Copyright 2009 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 gob
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import (
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"io";
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"os";
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)
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// DecodeUint reads an encoded unsigned integer from r.
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func DecodeUint(r io.Reader) (x uint64, err os.Error) {
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var buf [1]byte;
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for shift := uint(0);; shift += 7 {
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n, err := r.Read(&buf);
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if n != 1 {
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return 0, err
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}
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b := uint64(buf[0]);
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x |= b << shift;
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if b&0x80 != 0 {
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x &^= 0x80 << shift;
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break
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}
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}
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return x, nil;
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}
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// DecodeInt reads an encoded signed integer from r.
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func DecodeInt(r io.Reader) (i int64, err os.Error) {
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x, err := DecodeUint(r);
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if err != nil {
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return
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}
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if x & 1 != 0 {
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return ^int64(x>>1), nil
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}
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return int64(x >> 1), nil
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}
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