libgocryptfs/internal/inomap/qino.go
2021-08-16 17:14:14 +02:00

44 lines
1.0 KiB
Go

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