在我的项目中,有一个从整数创建字符串并将其写入文件的方法(使用strcat)。不幸的是,它存在内存泄漏问题。在追踪该泄漏时,我将代码简化为以下形式。但是我似乎无法找到或修复它。这是该代码:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(int argc, char* argv[] )
{
char* output = "\0";
int counter = 5;
while(counter > 0)
{
char buffer[20];
sprintf(buffer, "%u", counter);
char* temp;
temp = malloc((strlen(output) + strlen(buffer) + 1));
strcpy(temp, buffer);
strcat(temp, output);
char* oldmemory = output;
output = temp;
free(oldmemory);
counter--;
}
printf("output: %s\n", output);
free(output);
return 0;
}
Valgrind返回:
==7125== Memcheck, a memory error detector
==7125== Copyright (C) 2002-2009, and GNU GPL'd, by Julian Seward et al.
==7125== Using Valgrind-3.6.0.SVN-Debian and LibVEX; rerun with -h for copyright info
==7125== Command: ./foo
==7125== Parent PID: 4455
==7125==
==7125== Invalid free() / delete / delete[]
==7125== at 0x4024B3A: free (vg_replace_malloc.c:366)
==7125== by 0x8048662: main (foo.c:20)
==7125== Address 0x8048780 is not stack'd, malloc'd or (recently) free'd
==7125==
==7125==
==7125== HEAP SUMMARY:
==7125== in use at exit: 0 bytes in 0 blocks
==7125== total heap usage: 5 allocs, 6 frees, 20 bytes allocated
==7125==
==7125== All heap blocks were freed -- no leaks are possible
==7125==
==7125== For counts of detected and suppressed errors, rerun with: -v
==7125== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 15 from 8)
内存泄漏在哪里,我该如何解决?