mycorrhiza/hyphae/interface.go
2022-02-19 11:31:54 +03:00

98 lines
2.3 KiB
Go

package hyphae
import (
"regexp"
"strings"
"sync"
)
// HyphaPattern is a pattern which all hyphae names must match.
var HyphaPattern = regexp.MustCompile(`[^?!:#@><*|"'&%{}]+`)
// IsValidName checks for invalid characters and path traversals.
func IsValidName(hyphaName string) bool {
if !HyphaPattern.MatchString(hyphaName) {
return false
}
for _, segment := range strings.Split(hyphaName, "/") {
if segment == ".git" || segment == ".." {
return false
}
}
return true
}
type HyphaKind int
const (
HyphaText HyphaKind = iota
HyphaMedia
)
// Hypher is a temporary name for this interface. The name will become NonEmptyHypha, once the struct with the said name is deprecated for good.
type Hypher interface {
sync.Locker
CanonicalName() string
HasTextPart() bool
TextPartPath() string
}
// DeleteHypha deletes the hypha from the storage.
func DeleteHypha(h Hypher) {
byNamesMutex.Lock()
h.Lock()
delete(byNames, h.CanonicalName())
decrementCount()
byNamesMutex.Unlock()
h.Unlock()
}
// RenameHyphaTo renames a hypha and performs respective changes in the storage.
func RenameHyphaTo(h Hypher, newName string) {
byNamesMutex.Lock()
h.Lock()
delete(byNames, h.CanonicalName())
h.(*NonEmptyHypha).SetName(newName)
byNames[h.CanonicalName()] = h.(*NonEmptyHypha)
byNamesMutex.Unlock()
h.Unlock()
}
// insert inserts the hypha into the storage, possibly overwriting the previous hypha with the same name. Count incrementation is done if needed.
func insert(h Hypher) (madeNewRecord bool) {
_, recorded := byNames[h.CanonicalName()]
byNamesMutex.Lock()
byNames[h.CanonicalName()] = h
byNamesMutex.Unlock()
if !recorded {
incrementCount()
}
return !recorded
}
// InsertIfNew checks whether the hypha exists and returns `true` if it didn't and has been created.
func InsertIfNew(h Hypher) (madeNewRecord bool) {
switch ByName(h.CanonicalName()).(type) {
case *EmptyHypha:
return insert(h)
default:
return false
}
}
// ByName returns a hypha by name. It returns an *EmptyHypha if there is no such hypha. This function is the only source of empty hyphae.
func ByName(hyphaName string) (h Hypher) {
byNamesMutex.Lock()
defer byNamesMutex.Unlock()
h, recorded := byNames[hyphaName]
if recorded {
return h
}
return NewEmptyHypha(hyphaName)
}