restic/internal/fuse/inode.go

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//go:build darwin || freebsd || linux
// +build darwin freebsd linux
package fuse
import (
"encoding/binary"
"github.com/cespare/xxhash/v2"
"github.com/restic/restic/internal/restic"
)
const prime = 11400714785074694791 // prime1 from xxhash.
// inodeFromName generates an inode number for a file in a meta dir.
func inodeFromName(parent uint64, name string) uint64 {
inode := prime*parent ^ xxhash.Sum64String(cleanupNodeName(name))
// Inode 0 is invalid and 1 is the root. Remap those.
if inode < 2 {
inode += 2
}
return inode
}
// inodeFromNode generates an inode number for a file within a snapshot.
func inodeFromNode(parent uint64, node *restic.Node) (inode uint64) {
if node.Links > 1 && node.Type != "dir" {
// If node has hard links, give them all the same inode,
// irrespective of the parent.
var buf [16]byte
binary.LittleEndian.PutUint64(buf[:8], node.DeviceID)
binary.LittleEndian.PutUint64(buf[8:], node.Inode)
inode = xxhash.Sum64(buf[:])
} else {
// Else, use the name and the parent inode.
// node.{DeviceID,Inode} may not even be reliable.
inode = prime*parent ^ xxhash.Sum64String(cleanupNodeName(node.Name))
}
// Inode 0 is invalid and 1 is the root. Remap those.
if inode < 2 {
inode += 2
}
return inode
}