查看内存泄露

valgrind --tool=memcheck --leak-check=yes --log-file=hjpool ./cwmpd

Valgrind现在提供多个工具，其中最重要的是Memcheck，Cachegrind，Massif和Callgrind。Memcheck这个工具可以用来寻找c、c++和fortran程序中内存管理的错误。Memcheck可以检查出下列几种内存操作上的错误：

• 读写已经释放的内存，或同一个malloc的内存块释放多次
• 读写内存块越界（从前或者从后）
• 使用还未初始化的变量
• 将无意义的参数传递给系统调用
• 内存泄漏

下面的程序犯有错误：

#include <string.h>

int foo(int x)
{
        if (x < 0)
                printf("%d ", x);

        return 0;
}

int main(int argc, char *argv[])
{
        char *ptr, *ptr1;
        int x, y[10];

        /* malloc without free */
        ptr = (char*) malloc(10);
        strcpy(ptr, "01234567890");

        /* not initialized memory */
        foo(x);
        
        /* more free */
        ptr1 = (char*) malloc(10);
        ptr1[0] = '\0';
        free(ptr1);
        free(ptr1);
        
        /* array overflow */
        y[11] = 0;

        return 0;
}    

使用Valgrind运行它：

valgrind --tool=memcheck --leak-check=yes ./test

得到如下结果：

==21412== Memcheck, a memory error detector.
==21412== Copyright (C) 2002-2007, and GNU GPL'd, by Julian Seward et al.
==21412== Using LibVEX rev 1854, a library for dynamic binary translation.
==21412== Copyright (C) 2004-2007, and GNU GPL'd, by OpenWorks LLP.
==21412== Using valgrind-3.3.1-Debian, a dynamic binary instrumentation framework.
==21412== Copyright (C) 2000-2007, and GNU GPL'd, by Julian Seward et al.
==21412== For more details, rerun with: -v
==21412== 
==21412== Invalid write of size 1
==21412==    at 0x4026A08: memcpy (mc_replace_strmem.c:402)
==21412==    by 0x80484C4: main (test.c:18)
==21412==  Address 0x419d032 is 0 bytes after a block of size 10 alloc'd
==21412==    at 0x4025D2E: malloc (vg_replace_malloc.c:207)
==21412==    by 0x80484A6: main (test.c:17)
==21412== 
==21412== Invalid write of size 1
==21412==    at 0x4026A11: memcpy (mc_replace_strmem.c:402)
==21412==    by 0x80484C4: main (test.c:18)
==21412==  Address 0x419d033 is 1 bytes after a block of size 10 alloc'd
==21412==    at 0x4025D2E: malloc (vg_replace_malloc.c:207)
==21412==    by 0x80484A6: main (test.c:17)
==21412== 
==21412== Conditional jump or move depends on uninitialised value(s)
==21412==    at 0x804846E: foo (test.c:5)
==21412==    by 0x80484CF: main (test.c:21)
==21412== 
==21412== Use of uninitialised value of size 4
==21412==    at 0x407D7B6: (within /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x4081380: vfprintf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x4088C3F: printf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x8048482: foo (test.c:6)
==21412==    by 0x80484CF: main (test.c:21)
==21412== 
==21412== Conditional jump or move depends on uninitialised value(s)
==21412==    at 0x407D7BE: (within /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x4081380: vfprintf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x4088C3F: printf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x8048482: foo (test.c:6)
==21412==    by 0x80484CF: main (test.c:21)
==21412== 
==21412== Conditional jump or move depends on uninitialised value(s)
==21412==    at 0x407F76E: vfprintf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x4088C3F: printf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x8048482: foo (test.c:6)
==21412==    by 0x80484CF: main (test.c:21)
==21412== 
==21412== Conditional jump or move depends on uninitialised value(s)
==21412==    at 0x4081C5E: vfprintf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x4088C3F: printf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x8048482: foo (test.c:6)
==21412==    by 0x80484CF: main (test.c:21)
==21412== 
==21412== Conditional jump or move depends on uninitialised value(s)
==21412==    at 0x407F818: vfprintf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x4088C3F: printf (in /lib/tls/i686/cmov/libc-2.8.90.so)
==21412==    by 0x8048482: foo (test.c:6)
==21412==    by 0x80484CF: main (test.c:21)
==21412== 
==21412== Invalid free() / delete / delete[]
==21412==    at 0x4024B4A: free (vg_replace_malloc.c:323)
==21412==    by 0x80484FA: main (test.c:27)
==21412==  Address 0x419d068 is 0 bytes inside a block of size 10 free'd
==21412==    at 0x4024B4A: free (vg_replace_malloc.c:323)
==21412==    by 0x80484EF: main (test.c:26)
-1091741928 ==21412== 
==21412== ERROR SUMMARY: 27 errors from 9 contexts (suppressed: 11 from 1)
==21412== malloc/free: in use at exit: 10 bytes in 1 blocks.
==21412== malloc/free: 2 allocs, 2 frees, 20 bytes allocated.
==21412== For counts of detected errors, rerun with: -v
==21412== searching for pointers to 1 not-freed blocks.
==21412== checked 51,468 bytes.
==21412== 
==21412== 
==21412== 10 bytes in 1 blocks are definitely lost in loss record 1 of 1
==21412==    at 0x4025D2E: malloc (vg_replace_malloc.c:207)
==21412==    by 0x80484A6: main (test.c:17)
==21412== 
==21412== LEAK SUMMARY:
==21412==    definitely lost: 10 bytes in 1 blocks.
==21412==      possibly lost: 0 bytes in 0 blocks.
==21412==    still reachable: 0 bytes in 0 blocks.
==21412==         suppressed: 0 bytes in 0 blocks.

转自：

http://code.google.com/p/ldd6410/wiki/Valgrind