56 lines
1.4 KiB
Go
56 lines
1.4 KiB
Go
// Copyright 2015 CoreOS, 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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package storage
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import "encoding/binary"
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type revision struct {
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main int64
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sub int64
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}
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func (a revision) GreaterThan(b revision) bool {
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if a.main > b.main {
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return true
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}
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if a.main < b.main {
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return false
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}
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return a.sub > b.sub
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}
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func newRevBytes() []byte {
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return make([]byte, 8+1+8)
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}
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func revToBytes(rev revision, bytes []byte) {
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binary.BigEndian.PutUint64(bytes, uint64(rev.main))
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bytes[8] = '_'
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binary.BigEndian.PutUint64(bytes[9:], uint64(rev.sub))
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}
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func bytesToRev(bytes []byte) revision {
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return revision{
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main: int64(binary.BigEndian.Uint64(bytes[0:8])),
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sub: int64(binary.BigEndian.Uint64(bytes[9:])),
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}
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}
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type revisions []revision
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func (a revisions) Len() int { return len(a) }
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func (a revisions) Less(i, j int) bool { return a[j].GreaterThan(a[i]) }
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func (a revisions) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
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