最近学习stl源码编程，一直想自己实现一个内存池，恰好前段时间2015阿里实习笔试有一道内存池的题目，将代码写在这里了。
//
// Created by ma on 2015/6/28.
//#ifndef MEMORYPOOL_H_
#define MEMORYPOOL_H_
#include typedef enum M_P_SIZE{
INIT_SIZE=16,
ADD_BUFF_SIZE=32
}M_P_SIZE;
class MemoryPool {
public:
MemoryPool(size_t buff_size=1,size_t freesize=INIT_SIZE);
~MemoryPool();
void *allocate();
void deallocate(void *p);
size_t chuck(const size_t n);
size_t get_free_buff_size() const { return free_buffer_size;
}
size_t get_total_buff_size() const{ return total_buff_size;
}private:
typedef union node{
void *data;
node* next;
}node;
size_t free_buffer_size;
size_t total_buff_size;
node* free_start;
size_t buff_size;
};
#endif //MEMORYPOOL_H_
//
// Created by ma on 2015/6/28.
//#include
#include "MemoryPool.h"void *MemoryPool::allocate() {
if(free_buffer_size <=0)
{
size_t n= total_buff_size > ADD_BUFF_SIZE ? total_buff_size >>1 : INIT_SIZE;
size_t res=chuck(n);
if(res==0)
return NULL;
free_buffer_size =res;
total_buff_size +=res;
}void *data=https://www.it610.com/article/free_start;
free_start=free_start->next;
free_buffer_size--;
return data;
}void MemoryPool::deallocate(void *p) {
node* q=(node*)p;
q->next=free_start;
free_start=q;
free_buffer_size++;
}
MemoryPool::~MemoryPool() {
while (free_start)
{
node* p=free_start;
free_start=free_start->next;
free(p);
}}
MemoryPool::MemoryPool(size_t buff_size, size_t freesize):free_start(NULL){size_t least_buf_size=sizeof(node);
this->buff_size = buff_size>least_buf_size?buff_size:least_buf_size;
size_t res = chuck(freesize);
total_buff_size = res;
free_buffer_size = res;
}
size_t MemoryPool::chuck(const size_t n) {
for (size_t i=0;
inext=free_start;
free_start=pnode;
}} 【c++ 固定分配大小的简单内存池】随后附上一段小测试代码，验证正确运行。
#include
#include "MemoryPool.h"
#include "vector"
using namespace std;
int main()
{
vector i_vec;
MemoryPool *m_pool=new MemoryPool(sizeof(int),16);
for(size_t i=0;
i<100;
i++) {
int *a = (int *) (m_pool->allocate());
*a=(int)i;
i_vec.push_back(a);
}cout<<"free_buff_size="<get_free_buff_size()< 推荐阅读
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