TarsCloud_TarsCpp/servant/jmem/jmem_queue.h
2018-09-05 11:26:21 +08:00

173 lines
4.4 KiB
C++

/**
* Tencent is pleased to support the open source community by making Tars available.
*
* Copyright (C) 2016THL A29 Limited, a Tencent company. All rights reserved.
*
* Licensed under the BSD 3-Clause License (the "License"); you may not use this file except
* in compliance with the License. You may obtain a copy of the License at
*
* https://opensource.org/licenses/BSD-3-Clause
*
* 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.
*/
#ifndef _JMEM_QUEUE_H
#define _JMEM_QUEUE_H
#include "util/tc_mem_queue.h"
#include "jmem/jmem_policy.h"
#include "tup/Tars.h"
namespace tars
{
/**
* 基于Tars协议的内存循环队列
* 编解码出错则抛出TarsDecodeException和TarsEncodeException
* 可以对锁策略和存储策略进行组合, 例如:
* 基于信号量锁, 文件存储的队列:
* TarsQueue<Test::QueueElement, SemLockPolicy, FileStorePolicy>
* 基于信号量锁, 共享内存存储的队列
* TarsQueue<Test::QueueElement, SemLockPolicy, ShmStorePolicy>
* 基于线程锁, 内存存储的队列
* TarsQueue<Test::QueueElement, ThreadLockPolicy, MemStorePolicy>
*
* 使用上, 不同的组合, 初始化函数不完全一样
* 初始化函数有:
* SemLockPolicy::initLock(key_t)
* ShmStorePolicy::initStore(key_t, size_t)
* FileStorePolicy::initStore(const char *file, size_t)
* 等, 具体参见jmem_policy.h
*/
template<typename T,
typename LockPolicy,
template<class,class> class StorePolicy>
class TarsQueue : public StorePolicy<TC_MemQueue, LockPolicy>
{
public:
/**
* 弹出一个元素
* @param t
*
* @return bool,true:成功, false:无元素
*/
bool pop_front(T &t)
{
string s;
{
TC_LockT<typename LockPolicy::Mutex> lock(LockPolicy::mutex());
if(!this->_t.pop_front(s))
{
return false;
}
}
tars::TarsInputStream<BufferReader> is;
is.setBuffer(s.c_str(), s.length());
t.readFrom(is);
return true;
}
/**
* 插入到队列
* @param t
*
* @return bool, ture:成功, false:队列满
*/
bool push_back(const T &t)
{
tars::TarsOutputStream<BufferWriter> os;
t.writeTo(os);
TC_LockT<typename LockPolicy::Mutex> lock(LockPolicy::mutex());
return this->_t.push_back(os.getBuffer(), os.getLength());
}
/**
* 是否满了
* @param t
*
* @return bool
*/
bool isFull(const T &t)
{
tars::TarsOutputStream<BufferWriter> os;
t.writeTo(os);
TC_LockT<typename LockPolicy::Mutex> lock(LockPolicy::mutex());
return this->_t.isFull(os.getLength());
}
/**
* 获取空闲的空间大小
*/
size_t getFreeSize()
{
TC_LockT<typename LockPolicy::Mutex> lock(LockPolicy::mutex());
return this->_t.getFreeSize();
}
/**
* 队列是否满
* @param : iSize, 输入数据块长度
* @return bool , true:满, false: 非满
*/
bool isFull(size_t iSize)
{
TC_LockT<typename LockPolicy::Mutex> lock(LockPolicy::mutex());
return this->_t.isFull(iSize);
}
/**
* 队列是否空
* @return bool , true: 满, false: 非满
*/
bool isEmpty()
{
TC_LockT<typename LockPolicy::Mutex> lock(LockPolicy::mutex());
return this->_t.isEmpty();
}
/**
* 队列中元素个数, 不加锁的情况下不保证一定正确
* @return size_t, 元素个数
*/
size_t elementCount()
{
TC_LockT<typename LockPolicy::Mutex> lock(LockPolicy::mutex());
return this->_t.elementCount();
}
/**
* 队列长度(字节), 小于总存储区长度(总存储区长度包含了控制快)
* @return size_t : 队列长度
*/
size_t queueSize()
{
TC_LockT<typename LockPolicy::Mutex> lock(LockPolicy::mutex());
return this->_t.queueSize();
}
/**
* 共享内存长度
* @return size_t : 共享内存长度
*/
size_t memSize() const
{
TC_LockT<typename LockPolicy::Mutex> lock(LockPolicy::mutex());
return this->_t.memSize();
};
};
}
#endif