| // Licensed to the Apache Software Foundation (ASF) under one or more |
| // contributor license agreements. See the NOTICE file distributed with |
| // this work for additional information regarding copyright ownership. |
| // The ASF licenses this file to You under the Apache License, Version 2.0 |
| // (the "License"); you may not use this file except in compliance with |
| // the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package bandeps |
| |
| import ( |
| "sync" |
| ) |
| |
| // You can never hold more than one key at a time! We do not enforce lock ordering! |
| type keyRWLock struct { |
| keyToRWLock map[string]*sync.RWMutex |
| lock sync.Mutex |
| } |
| |
| func newKeyRWLock() *keyRWLock { |
| return &keyRWLock{ |
| keyToRWLock: make(map[string]*sync.RWMutex), |
| } |
| } |
| |
| func (k *keyRWLock) RLock(key string) { |
| k.getRWLock(key).Lock() |
| } |
| |
| func (k *keyRWLock) RUnlock(key string) { |
| k.getRWLock(key).Unlock() |
| } |
| |
| func (k *keyRWLock) Lock(key string) { |
| k.getRWLock(key).Lock() |
| } |
| |
| func (k *keyRWLock) Unlock(key string) { |
| k.getRWLock(key).Unlock() |
| } |
| |
| func (k *keyRWLock) getRWLock(key string) *sync.RWMutex { |
| k.lock.Lock() |
| rwLock, ok := k.keyToRWLock[key] |
| if !ok { |
| rwLock = &sync.RWMutex{} |
| k.keyToRWLock[key] = rwLock |
| } |
| k.lock.Unlock() |
| return rwLock |
| } |