mirror of https://github.com/perkeep/perkeep.git
47 lines
1.2 KiB
Go
47 lines
1.2 KiB
Go
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/*
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Copyright 2013 Google Inc.
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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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http://www.apache.org/licenses/LICENSE-2.0
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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 diskpacked
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import (
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"os"
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"syscall"
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)
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const (
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// FALLOC_FL_KEEP_SIZE: default is extend size
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falloc_fl_keep_size = 0x01
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// FALLOC_FL_PUNCH_HOLE: de-allocates range
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falloc_fl_punch_hole = 0x02
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)
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func init() {
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punchHole = punchHoleLinux
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}
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// puncHoleLinux punches a hole into the given file starting at offset,
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// measuring "size" bytes
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func punchHoleLinux(file *os.File, offset int64, size int64) error {
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err := syscall.Fallocate(int(file.Fd()),
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falloc_fl_punch_hole|falloc_fl_keep_size,
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offset, size)
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if err == syscall.ENOSYS || err == syscall.EOPNOTSUPP {
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return errNoPunch
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}
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return err
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}
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