libgocryptfs/internal/fusefrontend_reverse/rpath_cache.go

46 lines
1.1 KiB
Go

package fusefrontend_reverse
import (
"sync"
)
// rPathCacheContainer is a simple one entry path cache. Because the dirIV
// is generated deterministically from the directory path, there is no need
// to ever invalidate entries.
type rPathCacheContainer struct {
sync.Mutex
// Relative ciphertext path to the directory
cPath string
// Relative plaintext path
pPath string
// Directory IV of the directory
dirIV []byte
}
// lookup relative ciphertext path "cPath". Returns dirIV, relative
// plaintext path.
func (c *rPathCacheContainer) lookup(cPath string) ([]byte, string) {
c.Lock()
defer c.Unlock()
if cPath == c.cPath {
// hit
return c.dirIV, c.pPath
}
// miss
return nil, ""
}
// store - write entry for the directory at relative ciphertext path "cPath"
// into the cache.
// "dirIV" = directory IV of the directory, "pPath" = relative plaintext path
func (c *rPathCacheContainer) store(cPath string, dirIV []byte, pPath string) {
c.Lock()
defer c.Unlock()
c.cPath = cPath
c.dirIV = dirIV
c.pPath = pPath
}
// rPathCache: see rPathCacheContainer above for a detailed description
var rPathCache rPathCacheContainer