alsa-内存泄漏？

Question

我一直在追寻内存泄漏（由“ valgrind –leak-check =
yes”报告），它似乎来自ALSA。这段代码已经存在于自由世界中一段时间​​了，所以我猜这是我做错的事情。

#include <stdio.h>
#include <stdlib.h>
#include <alsa/asoundlib.h>

int main (int argc, char *argv[])
{
    snd_ctl_t *handle;

    int err = snd_ctl_open( &handle, "hw:1", 0 );
    printf( "snd_ctl_open: %d\n", err );

    err = snd_ctl_close(handle);
    printf( "snd_ctl_close: %d\n", err );
}

输出看起来像这样：

[root@aeolus alsa]# valgrind --leak-check=yes ./test2
==16296== Memcheck, a memory error detector
==16296== Copyright (C) 2002-2012, and GNU GPL'd, by Julian Seward et al.
==16296== Using Valgrind-3.8.1 and LibVEX; rerun with -h for copyright info
==16296== Command: ./test2
==16296==
snd_ctl_open: 0
snd_ctl_close: 0
==16296==
==16296== HEAP SUMMARY:
==16296==     in use at exit: 22,912 bytes in 1,222 blocks
==16296==   total heap usage: 1,507 allocs, 285 frees, 26,236 bytes allocated
==16296==
==16296== 4 bytes in 2 blocks are possibly lost in loss record 1 of 62
==16296==    at 0x4007100: malloc (vg_replace_malloc.c:270)
==16296==    by 0x340F7F: strdup (in /lib/libc-2.5.so)
==16296==    by 0x624C6B5: ??? (in /lib/libasound.so.2.0.0)
==16296==    by 0x624CA5B: ??? (in /lib/libasound.so.2.0.0)
==16296==    by 0x624CD81: ??? (in /lib/libasound.so.2.0.0)
==16296==    by 0x624F311: snd_config_update_r (in /lib/libasound.so.2.0.0)
==16296==    by 0x624FAD7: snd_config_update (in /lib/libasound.so.2.0.0)
==16296==    by 0x625DA22: snd_ctl_open (in /lib/libasound.so.2.0.0)
==16296==    by 0x804852F: main (test2.cpp:9)

并继续一些页面

==16296== 2,052 bytes in 57 blocks are possibly lost in loss record 62 of 62
==16296==    at 0x4005EB4: calloc (vg_replace_malloc.c:593)
==16296==    by 0x624A268: ??? (in /lib/libasound.so.2.0.0)
==16296==    by 0x624A38F: ??? (in /lib/libasound.so.2.0.0)
==16296==    by 0x624CA33: ??? (in /lib/libasound.so.2.0.0)
==16296==    by 0x624CCC9: ??? (in /lib/libasound.so.2.0.0)
==16296==    by 0x624CD81: ??? (in /lib/libasound.so.2.0.0)
==16296==    by 0x624F311: snd_config_update_r (in /lib/libasound.so.2.0.0)
==16296==    by 0x624FAD7: snd_config_update (in /lib/libasound.so.2.0.0)
==16296==    by 0x625DA22: snd_ctl_open (in /lib/libasound.so.2.0.0)
==16296==    by 0x804852F: main (test2.cpp:9)
==16296==
==16296== LEAK SUMMARY:
==16296==    definitely lost: 0 bytes in 0 blocks
==16296==    indirectly lost: 0 bytes in 0 blocks
==16296==      possibly lost: 22,748 bytes in 1,216 blocks
==16296==    still reachable: 164 bytes in 6 blocks
==16296==         suppressed: 0 bytes in 0 blocks
==16296== Reachable blocks (those to which a pointer was found) are not shown.
==16296== To see them, rerun with: --leak-check=full --show-reachable=yes
==16296==
==16296== For counts of detected and suppressed errors, rerun with: -v
==16296== ERROR SUMMARY: 56 errors from 56 contexts (suppressed: 19 from 8)

这是由于我在一个项目中使用ALSA并开始看到这种巨大的泄漏……或者至少是所说泄漏的报告。

所以问题是：是我，ALSA或valgrind在这里遇到问题吗？

Answer 1

http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=MEMORY-
LEAK;hb=HEAD
说：

                          Memory leaks - really?
                          ----------------------

请注意，一些开发人员认为ALSA库存在一些内存泄漏。当然可以，但这是事实，但是在联系我们之前，请确保不要强行泄漏这些泄漏。

报告的最大泄漏是，全局配置已缓存以备下次使用。如果不想使用此功能，只需在所有snd _ _ open

（）调用之后调用snd_config_update_free_global（）。此功能将释放缓存。