podman

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/*
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 * Copyright 2021 ByteDance Inc.
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 *
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 * Licensed under the Apache License, Version 2.0 (the "License");
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 * you may not use this file except in compliance with the License.
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 * You may obtain a copy of the License at
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 *
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 *     http://www.apache.org/licenses/LICENSE-2.0
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 *
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 * Unless required by applicable law or agreed to in writing, software
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 * distributed under the License is distributed on an "AS IS" BASIS,
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 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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 * See the License for the specific language governing permissions and
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 * limitations under the License.
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 */
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package rt
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const (
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    MinInt48 int64 = -(1 << 47)
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    MaxInt48 int64 = +(1 << 47) - 1
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)
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func PackInt(v int) uint64 {
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    if u := uint64(v); int64(v) < MinInt48 || int64(v) > MaxInt48 {
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        panic("int48 out of range")
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    } else {
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        return ((u >> 63) << 47) | (u & 0x00007fffffffffff)
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    }
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}
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func UnpackInt(v uint64) int {
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    v &= 0x0000ffffffffffff
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    v |= (v >> 47) * (0xffff << 48)
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    return int(v)
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}
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