[PATCH] util: remove ATTRIBUTE_NONNULL from virDirClose declaration

[Laine Stump]

After short discussion on IRC, I pushed this as "trivial".

On 11/13/20 12:42 PM, Laine Stump wrote:
> Before commit 24d8968c, virDirClose took a DIR**, and that was never
> NULL, so its declaration included ATTRIBUTE_NONNULL(1). Since that
> commit, virDirClose takes a DIR*, and it may be NULL (e.g. if the DIR*
> is initialized to NULL and was never closed).
>
> Even though virDirClose() is currently only called implicitly (as the
> cleanup for a g_autoptr(DIR)), and (as I've just newly learned) the
> autocleanup function g_autoptr will only be called if the pointer in
> question is non-null (see the definition of
> _GLIB_AUTOPTR_CLEAR_FUNC_NAME in
> /usr/include/glib-2.0/glib/gmacros.h), it does still cause Coverity to
> complain that it *could* be called with a NULL, and it's also possible
> that in the future someone might add code that explicitly calls
> virDirClose.
>
> To eliminate the Coverity complaints, and protect against the
> hypothetical future where someone both explicitly calls virDirClose()
> with a potentially NULL value, *and* re-enables the nonnull directive
> when not building with Coverity (disabled by commit eefb881) this
> patch removes the ATTRIBUTE_NONNULL(1) from the declaration of
> virDirClose().
>
> Fixes: 24d8968cd0a718af4badbbc858b1b449fea7205a
> Details-Research-by: Dan Berrange <berrange at redhat.com>
> Signed-off-by: Laine Stump <laine at redhat.com>
> ---
>   src/util/virfile.h | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/src/util/virfile.h b/src/util/virfile.h
> index ba31a78e58..32505826ee 100644
> --- a/src/util/virfile.h
> +++ b/src/util/virfile.h
> @@ -269,8 +269,7 @@ int virDirOpenQuiet(DIR **dirp, const char *dirname)
>       ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) G_GNUC_WARN_UNUSED_RESULT;
>   int virDirRead(DIR *dirp, struct dirent **ent, const char *dirname)
>       ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) G_GNUC_WARN_UNUSED_RESULT;
> -void virDirClose(DIR *dirp)
> -    ATTRIBUTE_NONNULL(1);
> +void virDirClose(DIR *dirp);
>   G_DEFINE_AUTOPTR_CLEANUP_FUNC(DIR, virDirClose);
>   
>   int virFileMakePath(const char *path) G_GNUC_WARN_UNUSED_RESULT;