wip: migrate to mono-repo. SPN has already been moved to spn/

spn/docks/cranehooks.go

@@ -0,0 +1,46 @@
+package docks
+
+import (
+	"sync"
+
+	"github.com/safing/portbase/log"
+)
+
+var (
+	craneUpdateHook     func(crane *Crane)
+	craneUpdateHookLock sync.Mutex
+)
+
+// RegisterCraneUpdateHook allows the captain to hook into receiving updates for cranes.
+func RegisterCraneUpdateHook(fn func(crane *Crane)) {
+	craneUpdateHookLock.Lock()
+	defer craneUpdateHookLock.Unlock()
+
+	if craneUpdateHook == nil {
+		craneUpdateHook = fn
+	} else {
+		log.Error("spn/docks: crane update hook already registered")
+	}
+}
+
+// ResetCraneUpdateHook resets the hook for receiving updates for cranes.
+func ResetCraneUpdateHook() {
+	craneUpdateHookLock.Lock()
+	defer craneUpdateHookLock.Unlock()
+
+	craneUpdateHook = nil
+}
+
+// NotifyUpdate calls the registers crane update hook function.
+func (crane *Crane) NotifyUpdate() {
+	if crane == nil {
+		return
+	}
+
+	craneUpdateHookLock.Lock()
+	defer craneUpdateHookLock.Unlock()
+
+	if craneUpdateHook != nil {
+		craneUpdateHook(crane)
+	}
+}