forked from TrueCloudLab/restic
28 lines
549 B
Go
28 lines
549 B
Go
package fs
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import (
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"os"
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"golang.org/x/sys/unix"
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)
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func PreallocateFile(wr *os.File, size int64) error {
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// try contiguous first
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fst := unix.Fstore_t{
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Flags: unix.F_ALLOCATECONTIG | unix.F_ALLOCATEALL,
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Posmode: unix.F_PEOFPOSMODE,
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Offset: 0,
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Length: size,
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}
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err := unix.FcntlFstore(wr.Fd(), unix.F_PREALLOCATE, &fst)
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if err == nil {
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return nil
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}
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// just take preallocation in any form, but still ask for everything
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fst.Flags = unix.F_ALLOCATEALL
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err = unix.FcntlFstore(wr.Fd(), unix.F_PREALLOCATE, &fst)
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return err
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}
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