package librsync import ( "sync" ) // pointerMap holds Go *Patcher objects to pass to C. // Don't touch this data structure, instead use the storePatcher, getPatcher, // and dropPatcher functions. var patcherStore = struct { lock sync.Mutex store map[uintptr]*Patcher }{ store: make(map[uintptr]*Patcher), } // storePatcher stores the value and returns a reference to it, for use in a CGo // call. Use the same reference for dropPatcher. C callbacks can use getPatcher // to get the original value. func storePatcher(patcher *Patcher, id uintptr) { patcherStore.lock.Lock() defer patcherStore.lock.Unlock() if _, ok := patcherStore.store[id]; ok { // Just to be on the safe side. panic("pointer already stored") } patcherStore.store[id] = patcher } // getPatcher returns the value for the reference id. It returns nil if there // is no such reference. func getPatcher(id uintptr) *Patcher { patcherStore.lock.Lock() defer patcherStore.lock.Unlock() return patcherStore.store[id] } // dropPatcher unreferences the value so the garbage collector can free it's // memory. func dropPatcher(id uintptr) { patcherStore.lock.Lock() defer patcherStore.lock.Unlock() if _, ok := patcherStore.store[id]; !ok { panic("pointer not stored") } delete(patcherStore.store, id) }