c++程序内存泄露检測工具

功能：

      用于检測c++程序的内存泄露。

原理：

     事实上非常easy，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:

     因为在检測的过程中，须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、空暇链表，事实上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 }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、仅仅是在vc2005上測试通过，没有在其它平台上測试过

2、不支持多线程（兴许有可能支持）

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) #endif void 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 //须要实现的功能 //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 }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; //空暇链表的初始长度 #define FREE_LIST_INIT_LEN 16 //空暇链表的头指针 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); } //创建一个空暇节点链表，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，不会由于检測工具本身的性能，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'; //增加链表 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