44 lines
1.0 KiB
Go
44 lines
1.0 KiB
Go
package inomap
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import (
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"syscall"
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)
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type namespaceData struct {
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// Stat_t.Dev is uint64 on 32- and 64-bit Linux
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Dev uint64
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// Tag acts like an extension of the Dev field.
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// It is used by reverse mode for virtual files.
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// Normal (forward) mode does not use it and it
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// stays always zero there.
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Tag uint8
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}
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// QIno = Qualified Inode number.
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// Uniquely identifies a backing file through the
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// (device number, tag, inode number) tuple.
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type QIno struct {
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namespaceData
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// Stat_t.Ino is uint64 on 32- and 64-bit Linu
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Ino uint64
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}
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// NewQIno returns a filled QIno struct
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func NewQIno(dev uint64, tag uint8, ino uint64) QIno {
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return QIno{
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namespaceData: namespaceData{
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Dev: dev,
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Tag: tag,
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},
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Ino: ino,
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}
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}
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// QInoFromStat fills a new QIno struct with the passed Stat_t info.
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func QInoFromStat(st *syscall.Stat_t) QIno {
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// There are some architectures that use 32-bit values here
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// (darwin, freebsd-32, maybe others). Add an explicit cast to make
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// this function work everywhere.
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return NewQIno(uint64(st.Dev), 0, uint64(st.Ino))
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}
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