常用内存泄露检测手段 dmalloc, mpatrol mtrace memwatch dbgmem valgrind Electric Fence

╰+攻爆jí腚メ 2022-10-30 11:28 5阅读 0赞

# [dmalloc用法快速入门][dmalloc] #

[原文链接][Link 1]

常用内存泄露检测手段有

*  [1 mtrace][1_mtrace]
 *  [2 memwatch][2_memwatch]
 *  [3 mpatrol][3_mpatrol]
 *  [4 dmalloc][4_dmalloc]
 *  [5 dbgmem][5_dbgmem]
 *  [6 valgrind][6_valgrind]
 *  [7 Electric Fence][7_Electric Fence]

dmalloc是一个简单易用的C/C++内存leak检查工具，以一个运行库的方式发布。

dmalloc能够检查出直到程序运行结束还没有释放的内存，并且能够精确指出在  
哪个源文件的第几行。

dmalloc 主页： [http://dmalloc.com][http_dmalloc.com]

支持的平台：AIX, BSD/OS, DG/UX, Free/Net/OpenBSD, GNU/Hurd, HPUX, Irix, Linux, MS-DOG, NeXT, OSF, SCO, Solaris, SunOS, Ultrix, Unixware, Windoze, and even Unicos on a Cray T3E

最新版本： 5.5.2

安装：下载 [http://dmalloc.com/releases/dmalloc-5.5.2.tgz][http_dmalloc.com_releases_dmalloc-5.5.2.tgz]

1.  tar zxvf dmalloc-5.5.2.tgz
2.  cd dmalloc-5.5.2
3.  ./configure
4.  make
5.  make install

设置环境变量：  
对于 Bash, ksh, and zsh ([http://www.zsh.org/][http_www.zsh.org]), 在 \`.bashrc', \`.profile', or \`.zshrc'  
文件中加入一行 ( -b 参数表示针对Bash的输出):

function dmalloc \{ eval \`command dmalloc -b $\*\`; \}

然后重新登陆用户，或者执行: source ~/.bashrc 或 source ~/.profile

接下面执行:

1.  dmalloc -l logfile -i 100 low

在源文件中添加下面的C代码：

\#ifdef DMALLOC  
\#include "dmalloc.h"  
\#endif

编译使用的CFLAGS: -DDMALLOC -DDMALLOC\_FUNC\_CHECK

如： gcc -DDMALLOC -DDMALLOC\_FUNC\_CHECK dm\_test.c

执行:  
./a.out

运行上面的命令会在当前目录下生成 logfile文件，查看logfile的内容如下：

cat logfile

1.  1214894489: 2: Dmalloc version '5.5.2' from 'http://dmalloc.com/'
2.  1214894489: 2: flags = 0x4e48503, logfile 'logfile'
3.  1214894489: 2: interval = 100, addr = 0, seen \# = 0, limit = 0
4.  1214894489: 2: starting time = 1214894489
5.  1214894489: 2: process pid = 9560
6.  1214894489: 2: Dumping Chunk Statistics:
7.  1214894489: 2: basic-block 4096 bytes, alignment 8 bytes
8.  1214894489: 2: heap address range: 0xb8020000 to 0xb8029000, 36864 bytes
9.  1214894489: 2:     user blocks: 1 blocks, 4043 bytes (10%)
10. 1214894489: 2:    admin blocks: 8 blocks, 32768 bytes (89%)
11. 1214894489: 2:    total blocks: 9 blocks, 36864 bytes
12. 1214894489: 2: heap checked 1
13. 1214894489: 2: alloc calls: malloc 2, calloc 0, realloc 0, free 0
14. 1214894489: 2: alloc calls: recalloc 0, memalign 0, valloc 0
15. 1214894489: 2: alloc calls: new 0, delete 0
16. 1214894489: 2:   current memory in use: 11 bytes (2 pnts)
17. 1214894489: 2:  total memory allocated: 11 bytes (2 pnts)
18. 1214894489: 2:  max in use at one time: 11 bytes (2 pnts)
19. 1214894489: 2: max alloced with 1 call: 6 bytes
20. 1214894489: 2: max unused memory space: 53 bytes (82%)
21. 1214894489: 2: top 10 allocations:
22. 1214894489: 2:  total-size  count in-use-size  count  source
23. 1214894489: 2:           6      1           6      1  dm\_test.c:71
24. 1214894489: 2:           5      1           5      1  dm\_test.c:69
25. 1214894489: 2:          11      2          11      2  Total of 2
26. 1214894489: 2: Dumping Not-Freed Pointers Changed Since Start:
27. 1214894489: 2:  not freed: '0xb8028fc8|s1' (6 bytes) from 'dm\_test.c:71'
28. 1214894489: 2:  not freed: '0xb8028fe8|s1' (5 bytes) from 'dm\_test.c:69'
29. 1214894489: 2:  total-size  count  source
30. 1214894489: 2:           6      1  dm\_test.c:71
31. 1214894489: 2:           5      1  dm\_test.c:69
32. 1214894489: 2:          11      2  Total of 2
33. 1214894489: 2: ending time = 1214894489, elapsed since start = 0:00:00

那么，哪个地方的内存leak就一目了然了。

//====== dm\_test.c 源代码 =============

1.  \#include <stdio.h>
2.  \#include <stdlib.h>
3.  \#include <string.h>
4.   
5.  \#ifdef DMALLOC
6.  \#include <dmalloc.h>
7.  \#endif
8.   
9.  int main(int argc, char \*\*argv)
10. \{
11.    
12.     char \*str;
13.  
14.     str = malloc(5);
15.  
16.     str = malloc(6);
17.    
18.     return 0;
19. \}

[dmalloc]: https://www.cnblogs.com/wangkangluo1/archive/2012/06/05/2535509.html
[Link 1]: http://blog.chinaunix.net/space.php?uid=796091&do=blog&id=2035331
[1_mtrace]: http://elinux.org/Memory_Debuggers#mtrace
[2_memwatch]: http://elinux.org/Memory_Debuggers#memwatch
[3_mpatrol]: http://elinux.org/Memory_Debuggers#mpatrol
[4_dmalloc]: http://elinux.org/Memory_Debuggers#dmalloc
[5_dbgmem]: http://elinux.org/Memory_Debuggers#dbgmem
[6_valgrind]: http://elinux.org/Memory_Debuggers#valgrind
[7_Electric Fence]: http://elinux.org/Memory_Debuggers#Electric_Fence
[http_dmalloc.com]: http://dmalloc.com/
[http_dmalloc.com_releases_dmalloc-5.5.2.tgz]: http://dmalloc.com/releases/dmalloc-5.5.2.tgz
[http_www.zsh.org]: http://www.zsh.org/