meditime/vendor/github.com/dgraph-io/ristretto/z/file_linux.go

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/*
* Copyright 2020 Dgraph Labs, Inc. and Contributors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package z
import (
"fmt"
)
// Truncate would truncate the mmapped file to the given size. On Linux, we truncate
// the underlying file and then call mremap, but on other systems, we unmap first,
// then truncate, then re-map.
func (m *MmapFile) Truncate(maxSz int64) error {
if err := m.Sync(); err != nil {
return fmt.Errorf("while sync file: %s, error: %v\n", m.Fd.Name(), err)
}
if err := m.Fd.Truncate(maxSz); err != nil {
return fmt.Errorf("while truncate file: %s, error: %v\n", m.Fd.Name(), err)
}
var err error
m.Data, err = mremap(m.Data, int(maxSz)) // Mmap up to max size.
return err
}