mutex.go

// Copyright 2015 The Serviced Authors.
// Licensed 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 utils

import "sync"

type MutexMap struct {
	sync.Mutex
	locks map[string]*sync.RWMutex
}

func NewMutexMap() *MutexMap {
	return &MutexMap{
		locks: make(map[string]*sync.RWMutex),
	}
}

func (m *MutexMap) getLock(key string) (lock *sync.RWMutex) {
	var ok bool
	m.Lock()
	defer m.Unlock()
	if lock, ok = m.locks[key]; !ok {
		lock = &sync.RWMutex{}
		m.locks[key] = lock
	}
	return
}

func (m *MutexMap) LockKey(key string) {
	m.getLock(key).Lock()
}

func (m *MutexMap) RLockKey(key string) {
	m.getLock(key).RLock()
}

func (m *MutexMap) UnlockKey(key string) {
	m.getLock(key).Unlock()
}

func (m *MutexMap) RUnlockKey(key string) {
	m.getLock(key).RUnlock()
}

func (m *MutexMap) DeleteKey(key string) {
	delete(m.locks, key)
}