[systemd-devel] [PATCH 0/5] Coverity fixes

[Philippe De Swert]

Hi,

On 10/09/14 13:30, Mantas Mikulėnas wrote:
> On Wed, Sep 10, 2014 at 1:20 PM, Philippe De Swert
>> On a side note I noticed this mail :
>> http://permalink.gmane.org/gmane.comp.sysutils.systemd.devel/6248
>>
>> Talking about some freeing macros. I noticed there seem to be some
>> here and there. So it would be good to know what they are. As a lot
>> of the errors seem to be leaking fd's and the like.
> 
> gcc has a "cleanup" attribute for variables, which makes the compiler
> automatically add a call to the specified function as soon as the
> variable goes out of scope.
> 
> systemd uses this liberally, and has convenience macros like
> _cleanup_close_ to automatically close fd's when returning from a
> function, so they don't actually leak when declared like that.
> 
> The message you linked to actually describes exactly this...

Ok so it has been taken into use and can actually somehow be considered part of 
the coding style? The mail was still speculating about it and I could not
quickly see a confirmation of this.

So to fix an fd leak this would be the preferred way right, instead of doing 
a close() call?

>From cfd7f340bc7cdb36498993e665058795422c9152 Mon Sep 17 00:00:00 2001
From: Philippe De Swert <philippedeswert at gmail.com>
Date: Wed, 10 Sep 2014 13:45:33 +0300
Subject: [PATCH] [fd leak] Stop leaking an fd in sd_journal_sendv

Found with Coverity. Fixes: CID#996435

Signed-off-by: Philippe De Swert <philippedeswert at gmail.com>
---
 src/journal/journal-send.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/journal/journal-send.c b/src/journal/journal-send.c
index bb1ef66..e9de638 100644
--- a/src/journal/journal-send.c
+++ b/src/journal/journal-send.c
@@ -198,7 +198,7 @@ finish:
 
 _public_ int sd_journal_sendv(const struct iovec *iov, int n) {
         PROTECT_ERRNO;
-        int fd;
+        _cleanup_close_ int fd;
         _cleanup_close_ int buffer_fd = -1;
         struct iovec *w;
         uint64_t *l;
-- 
1.8.3.2