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?
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。
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。