40 lines
1.3 KiB
Go
40 lines
1.3 KiB
Go
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// +build !linux
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/*
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* Copyright 2020 Dgraph Labs, Inc. and Contributors
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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 z
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import "fmt"
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// Truncate would truncate the mmapped file to the given size. On Linux, we truncate
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// the underlying file and then call mremap, but on other systems, we unmap first,
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// then truncate, then re-map.
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func (m *MmapFile) Truncate(maxSz int64) error {
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if err := m.Sync(); err != nil {
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return fmt.Errorf("while sync file: %s, error: %v\n", m.Fd.Name(), err)
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}
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if err := Munmap(m.Data); err != nil {
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return fmt.Errorf("while munmap file: %s, error: %v\n", m.Fd.Name(), err)
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}
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if err := m.Fd.Truncate(maxSz); err != nil {
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return fmt.Errorf("while truncate file: %s, error: %v\n", m.Fd.Name(), err)
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}
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var err error
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m.Data, err = Mmap(m.Fd, true, maxSz) // Mmap up to max size.
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return err
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}
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