#include "BlockMemaryPool.h"

using namespace base;

CBlockMemoryPool::CBlockMemoryPool(const int large_sz, const int add_num) : 
                                  _large_size(RoundUp(large_sz)), 
								  _number_large_add_nodes(add_num) {

}

CBlockMemoryPool::~CBlockMemoryPool() {
	// free all memory
	std::unique_lock<std::mutex> lock(_large_mutex);
	for (auto iter = _free_mem_vec.begin(); iter != _free_mem_vec.end(); ++iter) {
		free(*iter);		
	}
}

void* CBlockMemoryPool::PoolLargeMalloc() {
	if (_free_mem_vec.empty()) {
		Expansion();
	}
	
	std::unique_lock<std::mutex> lock(_large_mutex);
	void* ret = _free_mem_vec.front();
	_free_mem_vec.pop_back();
	return ret;
}

void CBlockMemoryPool::PoolLargeFree(void* &m) {
	std::unique_lock<std::mutex> lock(_large_mutex);
	_free_mem_vec.push_back(m);
}

int CBlockMemoryPool::GetSize() {
	std::unique_lock<std::mutex> lock(_large_mutex);
	return _free_mem_vec.size();
}

void CBlockMemoryPool::ReleaseHalf() {
	std::unique_lock<std::mutex> lock(_large_mutex);
	size_t size = _free_mem_vec.size();
	size_t hale = size / 2;
	for (auto iter = _free_mem_vec.begin(); iter != _free_mem_vec.end(); ++iter) {
		size--;
		if (size <= hale) {
			break;
		}
		void* mem = *iter;
		iter = _free_mem_vec.erase(iter);
		free(mem);
	}
}

void CBlockMemoryPool::Expansion(int num) {
	if (num = 0) {
		num = _number_large_add_nodes;
	}

	std::unique_lock<std::mutex> lock(_large_mutex);
	for (int i = 0; i < num; ++i) {
		void* mem = malloc(_large_size);
		// not memset!
		_free_mem_vec.push_back(mem);
	}
}