C语言多线程内存管理模块

1、C语言多线程内存管理模块摘要：一个多线程动态内存管理模块，可以有效地检测C语言中内存泄漏和内存越界等错误。1 原理l 分配通过重新改写内存分配函数，把调用时的信息保存在一个节点中，节点中包括此内存分配的首地址，大小以及分配所在的源文件、函数、行号，并用一个HASH表来保存所有节点。l 越界检测为了检测写越界的错误，在用户申请的内存前后各增加了一定大小的内存作为监测区域，并初始化成预定值（0xdeadbeef）。如果发生越界写操作时，预定值就会发生改变， 即可检测到越界操作错误。l 释放重新改写内存释放函数free，释放时节点从HASH表中删除并进行越界检测。l 查看手动调用show_memor

2、y()或show_memory_summary()查看内存使用情况并进行越界检测。以下涉及内存分配和内存释放的函数被重新改写：1. malloc2. calloc3. realloc4. strdup5. strndup6. asprintf7. vasprintfHASH表如下图所示：节点结构如下：static struct mm_region struct mm_region *next;char file40;/* 分配所在的文件 */char func40;/* 分配所在的函数 */unsigned int lineno;/* 分配所在的行 */size_t len;/* 内存分配的大

3、小 */unsigned int fence;/* 内存起始边界,用于头越界检测 */unsigned char data0;/* 用户内存分配首地址，malloc等函数返回以此为首地址的len长度的一块内存 */ *regionsSOME_PRIME;内存中一条节点的结构：nextfilefunclinenolenfence0xdeadbeefdatafence0xdeadbeefmm_region内存起始边界检测头越界内存结束边界检测尾越界2 测试步骤:1. 引入头文件：在需要检测的C/C+文件中引入”mm.h”头文件；2. 查看内存使用情况：调用show_memory()函数查看本文件中

4、内存泄漏详细情况，或调用show_memory_summary()函数查看本文件中内存泄漏统计情况。2.1 内存泄漏2.1.1 测试代码#include /* 加入头文件mm.h */#include mm.hint main(int argc, char *argv)char *mp = NULL;char *cp = NULL;mp = (char *)malloc(6);cp = (char *)calloc(1,10);/* 查看内存泄漏 */show_memory();show_memory_summary();return 0;2.1.2 测试结果2.2 内存越界2.2.1 测试代

5、码#include /* 加入头文件mm.h */#include mm.hint main(int argc, char *argv)char *mp = NULL;mp = (char *)malloc(6);/* 越界操作 */memset(mp,0, 10);/* 释放或查看内存时检测 */free(mp);return 0;2.2.2 测试结果2.3 释放错误此类错误包括：1. 释放空指针2. 释放野指针3. 重复释放4. 内存释放的起始地址与内存分配的起始地址不一致2.3.1 测试代码#include /* 加入头文件mm.h */#include mm.hint main(int

6、 argc, char *argv)char *mp = NULL;mp = (char *)malloc(6);free(mp);/* 重复释放*/free(mp);return 0;2.3.2 测试结果3 源码两个文件：”mm.h”和“mm.c”3.1 mm.h/* * mm.h* memory usage debugging (from Asterisk)*/#ifndef _MM_H_#define _MM_H_#ifdef _cplusplusextern C #endif/* Undefine any macros */#undef malloc#undef calloc#unde

7、f free#undef realloc#undef strdup#undef strndup#undef asprintf#undef vasprintfvoid *_mm_calloc(size_t nmemb, size_t size, const char *file, int lineno, const char *func);void *_mm_malloc(size_t size, const char *file, int lineno, const char *func);void _mm_free(void *ptr, const char *file, int linen

8、o, const char *func);void *_mm_realloc(void *ptr, size_t size, const char *file, int lineno, const char *func);char *_mm_strdup(const char *s, const char *file, int lineno, const char *func);char *_mm_strndup(const char *s, size_t n, const char *file, int lineno, const char *func);int _mm_asprintf(c

9、onst char *file, int lineno, const char *func, char *strp, const char *format, .);int _mm_vasprintf(char *strp, const char *format, va_list ap, const char *file, int lineno, const char *func);/* Provide our own definitions */#define calloc(a,b) _mm_calloc(a,b,_FILE_, _LINE_, _PRETTY_FUNCTION_)#defin

10、e malloc(a) _mm_malloc(a,_FILE_, _LINE_, _PRETTY_FUNCTION_)#define free(a) _mm_free(a,_FILE_, _LINE_, _PRETTY_FUNCTION_)#define realloc(a,b) _mm_realloc(a,b,_FILE_, _LINE_, _PRETTY_FUNCTION_)#define strdup(a) _mm_strdup(a,_FILE_, _LINE_, _PRETTY_FUNCTION_)#define strndup(a,b) _mm_strndup(a,b,_FILE_,

11、 _LINE_, _PRETTY_FUNCTION_)#define asprintf(a, b, c.) _mm_asprintf(_FILE_, _LINE_, _PRETTY_FUNCTION_, a, b, c)#define vasprintf(a,b,c) _mm_vasprintf(a,b,c,_FILE_, _LINE_, _PRETTY_FUNCTION_)int show_memory(void);int show_memory_summary(void);#ifdef _cplusplus#endif#endif /* _MM_H_ */3.2 mm.c/* mm.c*

12、Memory Management (from Asterisk)*/#include #include #include #include #include #include mm.h/* 本文中不使用自定义malloc,calloc,free等函数*/#undef malloc#undef calloc#undef realloc#undef strdup#undef strndup#undef free#undef vasprintf#undef asprintf#define SOME_PRIME 563#define FENCE_MAGIC 0xdeadbeefstatic stru

13、ct mm_region struct mm_region *next;char file40;/* 分配所在的文件*/char func40;/* 分配所在的函数*/unsigned int lineno;/* 分配所在的行*/size_t len;/* 内存分配的大小*/unsigned int fence;/* 内存起始边界,用于头越界检测*/unsigned char data0;/* 用户内存分配首地址，malloc等函数返回以此为首地址的len长度的一块内存*/ *regionsSOME_PRIME;#define HASH(a) (unsigned long)(a) % SOME

14、_PRIME)static pthread_mutex_t mmlock = PTHREAD_MUTEX_INITIALIZER;#define mm_log(.) do fprintf(stderr, _VA_ARGS_); while (0)static inline void *_mm_alloc_region(size_t size, const char *file, int lineno, const char *func)struct mm_region *reg;void *ptr = NULL;unsigned int *fence;int hash;if (!(reg =

15、(struct mm_region *)malloc(size + sizeof(*reg) + sizeof(*fence) ) /* 使用系统malloc */mm_log(Memory Allocation Failure - %d bytes in function %s at line %d of %sn, (int) size, func, lineno, file);strncpy(reg-file, file, sizeof(reg-file);strncpy(reg-func, func, sizeof(reg-func);reg-lineno = lineno;reg-le

16、n = size;ptr = reg-data;hash = HASH(ptr);/* 内存起始标志*/reg-fence = FENCE_MAGIC;/* 内存结束标志*/fence = (unsigned int *)(ptr + reg-len); *fence =FENCE_MAGIC;pthread_mutex_lock(&mmlock);reg-next = regionshash; /* 一个hash可能对应多个值*/ regionshash = reg;pthread_mutex_unlock(&mmlock);return ptr;static inline size_t _

17、mm_sizeof_region(void *ptr)int hash = HASH(ptr);struct mm_region *reg;size_t len = 0;pthread_mutex_lock(&mmlock);for (reg = regionshash; reg; reg = reg-next) if (reg-data = ptr) len = reg-len;break;pthread_mutex_unlock(&mmlock);return len;static void _mm_free_region(void *ptr, const char *file, int

18、lineno, const char *func)int hash = HASH(ptr);struct mm_region *reg, *prev = NULL;unsigned int *fence;pthread_mutex_lock(&mmlock);for (reg = regionshash; reg; reg = reg-next) if (reg-data = ptr) if (prev)prev-next = reg-next;elseregionshash = reg-next;break;prev = reg;pthread_mutex_unlock(&mmlock);i

19、f (reg) /* 头越界检测*/if (reg-fence != FENCE_MAGIC) mm_log(WARNING: Head fence violation at %p, in %s of %s, line %dn, reg-data, reg-func, reg-file, reg-lineno);/* 尾越界检测*/fence = (unsigned int *)(reg-data + reg-len);if ( *fence != FENCE_MAGIC) mm_log(WARNING: Tail fence violation at %p, in %s of %s, lin

20、e %dn, reg-data, reg-func, reg-file, reg-lineno);free(reg); else mm_log(WARNING: Freeing unused memory at %p, in %s of %s, line %dn,ptr, func, file, lineno);void *_mm_calloc(size_t nmemb, size_t size, const char *file, int lineno, const char *func) void *ptr;if (ptr = _mm_alloc_region(size * nmemb,

21、file, lineno, func) memset(ptr, 0, size * nmemb);return ptr;void *_mm_malloc(size_t size, const char *file, int lineno, const char *func) return _mm_alloc_region(size, file, lineno, func);void _mm_free(void *ptr, const char *file, int lineno, const char *func) _mm_free_region(ptr, file, lineno, func

22、);void *_mm_realloc(void *ptr, size_t size, const char *file, int lineno, const char *func) void *tmp;size_t len = 0;if (ptr & !(len = _mm_sizeof_region(ptr) mm_log(WARNING: Realloc of unalloced memory at %p, in %s of %s, line %dn, ptr, func, file, lineno);return NULL;if (!(tmp = _mm_alloc_region(si

23、ze, file, lineno, func)return NULL;if (len size)len = size;if (ptr) memcpy(tmp, ptr, len);_mm_free_region(ptr, file, lineno, func);return tmp;char *_mm_strdup(const char *s, const char *file, int lineno, const char *func) size_t len;void *ptr;if (!s)return NULL;len = strlen(s) + 1;if (ptr = _mm_allo

24、c_region(len, file, lineno, func)strcpy(char *)ptr, s);return (char *)ptr;char *_mm_strndup(const char *s, size_t n, const char *file, int lineno, const char *func) size_t len;void *ptr;if (!s)return NULL;len = strlen(s) + 1;if (len n)len = n;if (ptr = _mm_alloc_region(len, file, lineno, func)strcpy

25、(char *)ptr, s);return (char *)ptr;int _mm_asprintf(const char *file, int lineno, const char *func, char *strp, const char *fmt, .)int size;va_list ap, ap2;char s;*strp = NULL;va_start(ap, fmt);va_copy(ap2, ap);size = vsnprintf(&s, 1, fmt, ap2);va_end(ap2);if (!(*strp = (char *)_mm_alloc_region(size

26、 + 1, file, lineno, func) va_end(ap);return -1;vsnprintf(*strp, size + 1, fmt, ap);va_end(ap);return size;int _mm_vasprintf(char *strp, const char *fmt, va_list ap, const char *file, int lineno, const char *func) int size;va_list ap2;char s;*strp = NULL;va_copy(ap2, ap);size = vsnprintf(&s, 1, fmt,

27、ap2);va_end(ap2);if (!(*strp = (char *)_mm_alloc_region(size + 1, file, lineno, func) va_end(ap);return -1;vsnprintf(*strp, size + 1, fmt, ap);return size;int show_memory(void)char *fn = NULL;struct mm_region *reg;unsigned int x;unsigned int len = 0;unsigned int count = 0;unsigned int *fence;mm_log(

28、nLEAK DETAIL:n);pthread_mutex_lock(&mmlock);for (x = 0; x next) if (!fn | !strcasecmp(fn, reg-file) | !strcasecmp(fn, anomolies) /* 头越界检测*/if (reg-fence != FENCE_MAGIC) mm_log(WARNING: Head fence violation at %p, in %s of %s, line %dn, reg-data, reg-func, reg-file, reg-lineno);/* 尾越界检测*/fence = (uns

29、igned int *)(reg-data + reg-len);if ( *fence != FENCE_MAGIC) mm_log(WARNING: Tail fence violation at %p, in %s of %s, line %dn, reg-data, reg-func, reg-file, reg-lineno);if (!fn | !strcasecmp(fn, reg-file) mm_log(%10d bytes allocated in %20s at line %5d of %sn, (int) reg-len, reg-func, reg-lineno, reg-file);len += reg-len;count+;pthread_mutex_unlock(&mmlock);mm_log(%d bytes allocated in %d allocationsn, len, count);return 0;int show_memory_summary(v