内存管理：使用链式栈实现内存的有效管理与监控

原创已于 2023-05-26 09:37:14 修改 · 448 阅读

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#C数据结构

于 2015-08-05 20:21:59 首次发布

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声明部分  头文件mem.h

#include <stdio.h>
#include <stdlib.h>

//用于对所有C项目的内存的有效管理
void *mymalloc(size_t size);
void myfree(void *p);
void *myrealloc(void*p, size_t size);

struct MEM
{
	void *p;
	int size;
};

typedef struct LinkNode
{
	struct MEM *pmem;//保存内存指针
	struct LinkNode *pNext;//指向下一个节点
}node ,*PNODE;

struct LinkNode *phead;
PNODE addback(PNODE  phead, struct MEM *pmem);//插入一个数据
PNODE change(PNODE phead, void *pfind, struct MEM *pnewmem);//修改
PNODE findit(PNODE phead, void *pfind);
PNODE deletenode(PNODE phead, void *paddr);//删除  根据地址来删除
//显示所有信息
void showall(PNODE phead);
//获取内存信息  统计堆上的内存数量
void getinfo(PNODE phead);
PNODE deleteall(PNODE phead);

--------------------------------------------------------------

定义部分   mem.c

#include "mem.h"
struct LinkNode *phead = NULL;

void *mymalloc(size_t size)
{
	void *p = malloc(size);
	struct MEM *pmem = malloc(sizeof(struct MEM));
	pmem->p = p;
	pmem->size = size;//开辟一个结点
	phead = addback(phead, pmem);
	return p;
}
void myfree(void *p)
{
	PNODE *px = findit(phead, p);
	if (NULL==px  )
	{
		return;
	} 
	else
	{
		deletenode(phead, p);
		free(p);
	}
}
void *myrealloc(void*p, size_t size)
{
	void *pt = realloc(p, size);
	struct MEM mymem;
	mymem.p = pt;
	mymem.size = size;
	phead = change(phead, p, &mymem);
	return pt;
}
PNODE addback(PNODE  phead, struct MEM *pmem)//插入一个数据
{
	PNODE pnew = malloc(sizeof(node));
	pnew->pmem = pmem;
	pnew->pNext = NULL;//开辟一个节点
	if (phead==NULL)
	{
		phead = pnew;
	} 
	else
	{
		PNODE ptemp = phead;
		while (ptemp->pNext!=NULL)
		{
			ptemp = ptemp->pNext;
		}
		ptemp->pNext = pnew;
	}
	return phead;
}

PNODE change(PNODE phead, void *pfind, struct MEM *pnewmem)//修改
{
	for (PNODE p = phead; p != NULL;p=p->pNext)
	{
		if (p->pmem->p==pfind)
		{
			p->pmem->p = pnewmem->p;
			p->pmem->size = pnewmem->size;
			return phead;
		}
	}
	return phead;
}

PNODE findit(PNODE phead, void *pfind)
{
	for (PNODE p = phead; p != NULL; p = p->pNext)
	{
		if (p->pmem->p == pfind)
		{
			return p;
		}
	}
	return NULL;
}

PNODE deletenode(PNODE phead, void *paddr)//删除
{//双指针
	PNODE p1, p2;
	p1 = p2 = NULL;
	p1 = phead;
	while (p1!=NULL)
	{
		if (p1->pmem->p ==paddr)
		{
			break;
		} 
		else
		{
			p2 = p1;
			p1 = p1->pNext;//备份上一个地址
		}
	}
	if (p1!=phead)
	{
		p2->pNext = p1->pNext;
		free(p1);
	} 
	else
	{
		phead = phead->pNext;
		free(p1);
	}
	return phead;
}

void showall(PNODE phead)
{
	if (phead ==NULL)
	{
		return;
	} 
	else
	{
		printf("\nmemaddr=%p,size=%d", phead->pmem->p, phead->pmem->size);
		showall(phead->pNext);//遍历
	}
}

void getinfo(PNODE phead)
{
	printf("\n");
	int i = 0;//多少个地址
	int j = 0;//代表多少个字节内存
	for (PNODE p = phead; p != NULL; p = p->pNext)
	{
		i++;
		j += p->pmem->size;
		printf("\nmemaddr=%p,size=%d", p->pmem->p, p->pmem->size);
	}
	printf("\n目前一共%d个地址在使用，一共消耗%d内存", i, j);
}
//清除所有内存
PNODE deleteall(PNODE phead)
{
	if (NULL==phead )
	{
		return NULL;
	} 
	else
	{
		PNODE p1 = NULL;
		PNODE p2 = NULL;
		p1 = phead;
		while (p1->pNext!=NULL)
		{
			p2 = p1->pNext;
			p1->pNext = p2->pNext;//跳过p1
			free(p2->pmem->p);//释放p2指向的这片内存
			free(p2);
		}
		//最后释放头结点的内存地址
		free(phead->pmem->p);//释放内存
		free(phead);//最后释放头结点
		return NULL;
	}
}

------------------------------------------

主函数测试部分 mallocfree.c

#include "mem.h"
#define malloc mymalloc
#define free myfree
#define realloc myrealloc
void main()
{
	int a;
	int *p;
	void *p1 = malloc(1024 * 1024 *100);
	void *p2 = malloc(1024 * 1024 * 100);
	void *p3 = malloc(1024 * 1024 * 100);
	void *p4 = malloc(1024 * 1024 * 100);
	getinfo(phead);
	realloc(p1, 1024 * 1024 * 200);
	getinfo(phead);
	free(p2);
	free(p2);//允许重复释放 ok
	free(10003);//ok
	getinfo(phead);
	deleteall(phead);
	system("pause");
}