2024-12-10, I wrote:
> The change to openat-die.c triggers a new warning in gzip, from the gcc 13
> options
> -Wformat -Wformat-security
> Since this package's "make distcheck" enables -Werror, it even triggers an
> error:
>
> $ make distcheck
> ...
> CC libgzip_a-openat-die.o
> openat-die.c: In function 'openat_save_fail':
> openat-die.c:37:3: error: format not a string literal and no format arguments
> [-Werror=format-security]
> 37 | error (exit_failure, errnum,
> | ^~~~~
>
> The warning is pointless, since the gettext tools make sure that the localized
> variant of the string will not access nonexistent format arguments. Thus, it's
> only a code style warning, misplaced under the umbrella of "security".
Similarly with the change to xstdopen.c. It triggers a new warning in diffutils,
from the gcc 13 options
-Wformat -Wformat-security
Since this package's "make distcheck" enables -Werror, it even triggers an
error:
$ make distcheck
...
CC libdiffutils_a-xstdopen.o
xstdopen.c: In function 'xstdopen':
xstdopen.c:34:5: error: format not a string literal and no format arguments
[-Werror=format-security]
34 | error (exit_failure, stdopen_errno, _("standard file descriptors"));
| ^~~~~
xstdopen.c:34:5: error: format not a string literal and no format arguments
[-Werror=format-security]
cc1: all warnings being treated as errors
make[5]: *** [Makefile:6560: libdiffutils_a-xstdopen.o] Error 1
Again, the warning is pointless, since the gettext tools make sure that the
localized
variant of the string will not access nonexistent format arguments. Thus, it's
only a code style warning, misplaced under the umbrella of "security".
Additionally, the error message that would be printed is
standard file descriptors: No space left on device
which is more confusing than helpful. Let me, at the same time, improve the
error
message.
2024-12-17 Bruno Haible <br...@clisp.org>
xstdopen: Improve error message.
* lib/xstdopen.c (xstdopen): Improve error message. Ignore the errno
value.
diff --git a/lib/xstdopen.c b/lib/xstdopen.c
index 678c2a9d9f..b82f44f0a8 100644
--- a/lib/xstdopen.c
+++ b/lib/xstdopen.c
@@ -31,5 +31,9 @@ xstdopen (void)
{
int stdopen_errno = stdopen ();
if (stdopen_errno != 0)
- error (exit_failure, stdopen_errno, _("standard file descriptors"));
+ /* Ignore stdopen_errno in the error message, since it may be misleading
+ (see stdopen.c). */
+ error (exit_failure, 0,
+ _("failed to open all three standard file descriptors; maybe %s or
%s are not working right?"),
+ "/dev/null", "/dev/full");
}
