44 lines
925 B
Go
44 lines
925 B
Go
/*
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This package contains help functions for stable marshaller. Their usage is
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totally optional. One can implement fast stable marshaller without these
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runtime function calls.
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*/
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package proto
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import (
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"encoding/binary"
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"math/bits"
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)
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func BytesMarshal(field int, buf, v []byte) (int, error) {
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if len(v) == 0 {
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return 0, nil
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}
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// buf length check can prevent panic at PutUvarint, but it will make
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// marshaller a bit slower.
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prefix := field<<3 | 0x2
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i := binary.PutUvarint(buf, uint64(prefix))
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i += binary.PutUvarint(buf[i:], uint64(len(v)))
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i += copy(buf[i:], v)
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return i, nil
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}
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func BytesSize(field int, v []byte) int {
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ln := len(v)
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if ln == 0 {
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return 0
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}
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prefix := field<<3 | 0x2
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return VarUIntSize(uint64(prefix)) + VarUIntSize(uint64(ln)) + ln
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}
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// varUIntSize returns length of varint byte sequence for uint64 value 'x'.
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func VarUIntSize(x uint64) int {
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return (bits.Len64(x|1) + 6) / 7
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}
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