fixincludes: simplify handling for access() failure [PR21283, PR80047]
Commit Message
POSIX says:
On some implementations, if buf is a null pointer, getcwd() may obtain
size bytes of memory using malloc(). In this case, the pointer returned
by getcwd() may be used as the argument in a subsequent call to free().
Invoking getcwd() with buf as a null pointer is not recommended in
conforming applications.
This produces an error building GCC with --enable-werror-always:
../../../fixincludes/fixincl.c: In function ‘process’:
../../../fixincludes/fixincl.c:1356:7: error: argument 1 is null but
the corresponding size argument 2 value is 4096 [-Werror=nonnull]
It's suggested by POSIX to call getcwd() with progressively larger
buffers until it does not give an [ERANGE] error. However, it's highly
unlikely that this error-handling route is ever used.
So we can simplify it instead of writting too much code. We give up to
use getcwd(), because `make` will output a `Leaving directory ...` message
containing the path to cwd when we call abort().
fixincludes/ChangeLog:
PR other/21823
PR bootstrap/80047
* fixincl.c (process): Simplify the handling for highly
unlikely access() failure, to avoid using non-standard
extensions.
---
fixincludes/fixincl.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
Comments
Perfect.
On 11/12/21 1:58 PM, Xi Ruoyao wrote:
> diff --git a/fixincludes/fixincl.c b/fixincludes/fixincl.c
> index 6dba2f6e830..ee57fbf61b4 100644
> --- a/fixincludes/fixincl.c
> +++ b/fixincludes/fixincl.c
> @@ -1352,11 +1352,10 @@ process (void)
>
> if (access (pz_curr_file, R_OK) != 0)
> {
> - int erno = errno;
> - fprintf (stderr, "Cannot access %s from %s\n\terror %d (%s)\n",
> - pz_curr_file, getcwd ((char *) NULL, MAXPATHLEN),
> - erno, xstrerror (erno));
> - return;
> + /* Some really strange error happened. */
> + fprintf (stderr, "Cannot access %s: %s\n", pz_curr_file,
> + xstrerror (errno));
> + abort();
> }
>
> pz_curr_data = load_file (pz_curr_file);
On Sat, 2021-11-13 at 08:13 -0800, Bruce Korb wrote:
> Perfect.
Committed at r12-5234 with minor format fix.
> On 11/12/21 1:58 PM, Xi Ruoyao wrote:
> > diff --git a/fixincludes/fixincl.c b/fixincludes/fixincl.c
> > index 6dba2f6e830..ee57fbf61b4 100644
> > --- a/fixincludes/fixincl.c
> > +++ b/fixincludes/fixincl.c
> > @@ -1352,11 +1352,10 @@ process (void)
> >
> > if (access (pz_curr_file, R_OK) != 0)
> > {
> > - int erno = errno;
> > - fprintf (stderr, "Cannot access %s from %s\n\terror %d
> > (%s)\n",
> > - pz_curr_file, getcwd ((char *) NULL, MAXPATHLEN),
> > - erno, xstrerror (erno));
> > - return;
> > + /* Some really strange error happened. */
> > + fprintf (stderr, "Cannot access %s: %s\n", pz_curr_file,
> > + xstrerror (errno));
> > + abort();
> > }
> >
> > pz_curr_data = load_file (pz_curr_file);
@@ -1352,11 +1352,10 @@ process (void)
if (access (pz_curr_file, R_OK) != 0)
{
- int erno = errno;
- fprintf (stderr, "Cannot access %s from %s\n\terror %d (%s)\n",
- pz_curr_file, getcwd ((char *) NULL, MAXPATHLEN),
- erno, xstrerror (erno));
- return;
+ /* Some really strange error happened. */
+ fprintf (stderr, "Cannot access %s: %s\n", pz_curr_file,
+ xstrerror (errno));
+ abort();
}
pz_curr_data = load_file (pz_curr_file);