c++程序内存泄露检测工具

功能：

      用于检测c++程序的内存泄露。

原理：

     其实很简单，就是通过函数的重载机制，捕获应用程序的new, new[] , delete , delete[], malloc,calloc,free等内存操作函数。

特点:

     由于在检测的过程中，需要记录用户程序内存分配信息，所以工具本身必须进行内存动态分配。为了提高内存分配效率，程序实现了两个链表。

1、空闲链表，其实就是一个简单的内存池

//定义一个结构，保存内存分配信息typedef struct _tagMemoryInfo{ void* addr; //保存分配的内存地址 size_t size; //内存大小 _UL lineNum; //调用内存分配函数的行号 char fileName[MAX_FILE_LEN]; //文件名称}MemoryInfo;//内存分配信息的链表结构，这里之所以定义为union类型，是为了省去next成员的开销union FreeList{ FreeList* next; MemoryInfo data;};

 

2、当前正在保存内存信息的链表

typedef struct _tagBusyList{ _tagBusyList* next; MemoryInfo* data;}BusyList;

 

不足：

1、只是在vc2005上测试通过，没有在其他平台上测试过

2、不支持多线程（后续有可能支持）

3、保存当前内存分配信息的链表，存在next字段的内存开销。

 

源代码：

 

1、头文件

 

#ifdef DETECT_MEMORY_LEAK#ifndef _DETECT_MEMORY_LEAK_H_#define _DETECT_MEMORY_LEAK_H_typedef unsigned long _UL;void* __cdecl operator new(unsigned int size , _UL lineNum , const char* file);void* __cdecl operator new[](unsigned int size , _UL lineNum , const char* file);void __cdecl operator delete(void *p);void __cdecl operator delete [] (void *p);void __cdecl operator delete(void *p , _UL lineNum , const char* file);void __cdecl operator delete [] (void *p , _UL lineNum , const char* file);void* __cdecl _DebugMalloc(size_t size , _UL lineNum , const char* file);void* __cdecl _DebugCalloc(size_t num , size_t size , _UL lineNum , const char* file);void __cdecl _DebugFree(void* addr);#ifndef DETECT_MEMORY_LEAK_IMPL#define new DEBUG_NEW#define DEBUG_NEW new(__LINE__ , __FILE__)#define malloc DEBUG_MALLOC#define DEBUG_MALLOC(x) _DebugMalloc(x , __LINE__ , __FILE__)#define calloc DEBUG_CALLOC#define DEBUG_CALLOC(x) _DebugCalloc(x , __LINE__ , __FILE__)#define free DEBUG_FREE#define DEBUG_FREE(x) _DebugFree(x)#endifvoid DumpLeakedMemoryInfo();#endif//_DETECT_MEMORY_LEAK_H_#endif//DETECT_MEMORY_LEAK

2、源文件

 

#ifdef DETECT_MEMORY_LEAK#define DETECT_MEMORY_LEAK_IMPL#include "DetectMemoryLeak.h"#include "stdio.h"#include "string.h"#include "malloc.h"#define MAX_FILE_LEN 128//需要实现的功能//1 将分配的内存信息写入文件//2 将释放的内存信息写入文件//3 将分配的内存信息都保存到内存中，提供一个接口将当前的内存泄露情况报告出去。//定义一个结构，保存内存分配信息typedef struct _tagMemoryInfo{ void* addr; //保存分配的内存地址 size_t size; //内存大小 _UL lineNum; //调用内存分配函数的行号 char fileName[MAX_FILE_LEN]; //文件名称}MemoryInfo;//内存分配信息的链表结构，这里之所以定义为union类型，是为了省去next成员的开销union FreeList{ FreeList* next; MemoryInfo data;};typedef struct _tagBusyList{ _tagBusyList* next; MemoryInfo* data;}BusyList;//空闲链表的初始长度#define FREE_LIST_INIT_LEN 16//空闲链表的头指针static FreeList* g_freeList = NULL;//正在使用链表的头指针static BusyList* g_busyList = NULL;//内部使用函数的声明static void _CreateFreeList(int initLen);static void _ReleaseFreeList();static void* _GetFreeNode();static void* _GetBusyNode();static void _FreeNode(void* p);static void _WriteMemoryInfo(const MemoryInfo* pInfo , bool bAlloc);static void _StoreMemoryAllocInfo(void* addr , size_t size , _UL lineNum , const char* file);static void _StoreMemoryDeallocInfo(void* addr);void* __cdecl operator new(unsigned int size , _UL lineNum , const char* file){ void* p = ::operator new(size); _StoreMemoryAllocInfo(p , size , lineNum , file); return p; //return 0;}void __cdecl operator delete(void* p){_StoreMemoryDeallocInfo(p);}void __cdecl operator delete(void *p, _UL lineNum , const char* file){ lineNum;file; _StoreMemoryDeallocInfo(p);}void* __cdecl operator new[](unsigned int size , _UL lineNum , const char* file){ void* p = ::operator new(size); _StoreMemoryAllocInfo(p , size , lineNum , file); return p; }void __cdecl operator delete [] (void *p){ _StoreMemoryDeallocInfo(p);}void __cdecl operator delete [] (void *p , _UL lineNum , const char* file){lineNum;file;_StoreMemoryDeallocInfo(p);}void* __cdecl _DebugMalloc(size_t size , _UL lineNum , const char* file){ void* p = malloc(size);_StoreMemoryAllocInfo(p , size , lineNum , file);return p;}void* __cdecl _DebugCalloc(size_t num , size_t size , _UL lineNum , const char* file){void* p = calloc(num , size);_StoreMemoryAllocInfo(p , num * size , lineNum , file);return p;}void __cdecl _DebugFree(void* addr){_StoreMemoryDeallocInfo(addr);}//创建一个空闲节点链表，生成一个内存池，用以记录内存分配信息。//这样当频繁分配内存的时候，不会因为检测工具本身的性能，影响应用程序的性能。void _CreateFreeList(int initLen){ FreeList* p = (FreeList*)malloc(sizeof(FreeList) * initLen); g_freeList = p; for (int idx = 1; idx < initLen; ++idx) { p->next = p + idx; p++; } p->next = NULL;}void* _GetFreeNode(){ if ( g_freeList == NULL) { _CreateFreeList(FREE_LIST_INIT_LEN); if ( NULL == g_freeList ) { return NULL; } } FreeList* p = g_freeList; g_freeList = g_freeList->next; return (void*)p;}void* _GetBusyNode(void* addr){if ( g_busyList == NULL){return NULL;}if ( NULL == g_busyList->next){MemoryInfo* retNode = NULL;if (g_busyList->data->addr == addr){retNode = g_busyList->data; delete g_busyList;g_busyList = NULL; }return (void*)retNode;}BusyList* pre , *curr;pre = curr = g_busyList;while(curr){if (curr->data->addr == addr){BusyList* tmp = curr;MemoryInfo* retNode = curr->data;pre->next = curr->next;free((void*)tmp);return (void*)retNode;}pre = curr;curr = curr->next;} return NULL;}void _FreeNode(void* p){ if ( NULL == p) { return; } FreeList* tmpNode = (FreeList*)p; tmpNode->next = g_freeList; g_freeList = tmpNode;}//保存内存分配信息void _StoreMemoryAllocInfo(void* addr , size_t size , _UL lineNum , const char* file){ MemoryInfo* node = (MemoryInfo*)_GetFreeNode(); if ( NULL == node ) { return; } node->addr =addr; node->size = size; node->lineNum = lineNum; size_t len = strlen(file); len = len >= MAX_FILE_LEN ? MAX_FILE_LEN - 1 : len; strncpy(node->fileName , file , len);node->fileName[len] = '/0'; //加入链表 BusyList* busyNode = (BusyList*)malloc(sizeof(BusyList)); busyNode->data = node; if ( g_busyList == NULL ) { g_busyList = busyNode; busyNode->next = NULL; } else { busyNode->next = g_busyList; g_busyList = busyNode; } //写入文件 _WriteMemoryInfo(node , true);}//保存内存分配信息void _StoreMemoryDeallocInfo(void* addr){MemoryInfo* node = (MemoryInfo*)_GetBusyNode(addr);if ( NULL == node ){return;}//写入文件_WriteMemoryInfo(node , false); _FreeNode((void*)node);}//写日志函数void _WriteMemoryInfo(const MemoryInfo* pInfo , bool bAlloc){ if (pInfo != NULL) { FILE *fp = fopen("debugmemorylog.txt","a+"); if (!fp) return; fprintf(fp,"%p:/t%s/t%d line %s %d bytes/n",pInfo->addr, pInfo->fileName, pInfo->lineNum / , (bAlloc ? "allocated" : "freed") , pInfo->size); fflush(fp); fclose(fp); }}//将泄露的内存信息写到磁盘void DumpLeakedMemoryInfo(){FILE *fp = fopen("memoryleak.txt","a+");if (!fp)return;BusyList* p = g_busyList;while (p){BusyList* tmp = p;MemoryInfo* pInfo = tmp->data;if (pInfo != NULL){fprintf(fp,"%p:/t%s/t%d line leak %d bytes/n",pInfo->addr, pInfo->fileName, pInfo->lineNum , pInfo->size);}_FreeNode((void*)pInfo); delete tmp; tmp = NULL; p = p->next;}fflush(fp);fclose(fp);//释放内存池资源给操作系统 _ReleaseFreeList();}void _ReleaseFreeList(){ while(g_freeList){FreeList* tmp = g_freeList->next;delete g_freeList;g_freeList = tmp;}}#endif//DETECT_MEMORY_LEAK