[systemd-devel] [PATCH] udev: Remove hard-coded string offsets when parsing kernel command line.

[Richard W.M. Jones]

On Wed, Nov 05, 2014 at 12:54:21PM +0100, David Herrmann wrote:
> Hi
> 
> On Wed, Nov 5, 2014 at 10:16 AM, Richard W.M. Jones <rjones at redhat.com> wrote:
> > ---
> >  src/udev/udevd.c | 23 ++++++++++++-----------
> >  1 file changed, 12 insertions(+), 11 deletions(-)
> >
> > diff --git a/src/udev/udevd.c b/src/udev/udevd.c
> > index 193702c..340812b 100644
> > --- a/src/udev/udevd.c
> > +++ b/src/udev/udevd.c
> > @@ -968,6 +968,7 @@ static void kernel_cmdline_options(struct udev *udev) {
> >
> >          FOREACH_WORD_QUOTED(word, l, line, state) {
> >                  char *s, *opt;
> > +                const char *name;
> >
> >                  s = strndup(word, l);
> >                  if (!s)
> > @@ -979,24 +980,24 @@ static void kernel_cmdline_options(struct udev *udev) {
> >                  else
> >                          opt = s;
> >
> > -                if (startswith(opt, "udev.log-priority=")) {
> > +                if (startswith(opt, name = "udev.log-priority=")) {
> 
> This looks weird. Note that "startswith()" returns a pointer to the
> offset, so maybe we should restructure like this:
> 
> if ((value = startswith(opt, "udev.log-priority))) {
>         prio = util_log_priority(value);
>         ....
> }

Ah ... yes, that would be better.

Rich.

> I will try to fix this up myself. Lets see..
> 
> Thanks
> David
> 
> >                          int prio;
> >
> > -                        prio = util_log_priority(opt + 18);
> > +                        prio = util_log_priority(opt + strlen(name));
> >                          log_set_max_level(prio);
> >                          udev_set_log_priority(udev, prio);
> > -                } else if (startswith(opt, "udev.children-max=")) {
> > -                        r = safe_atoi(opt + 18, &arg_children_max);
> > +                } else if (startswith(opt, name = "udev.children-max=")) {
> > +                        r = safe_atoi(opt + strlen(name), &arg_children_max);
> >                          if (r < 0)
> > -                                log_warning("Invalid udev.children-max ignored: %s", opt + 18);
> > -                } else if (startswith(opt, "udev.exec-delay=")) {
> > -                        r = safe_atoi(opt + 16, &arg_exec_delay);
> > +                                log_warning("Invalid udev.children-max ignored: %s", opt + strlen(name));
> > +                } else if (startswith(opt, name = "udev.exec-delay=")) {
> > +                        r = safe_atoi(opt + strlen(name), &arg_exec_delay);
> >                          if (r < 0)
> > -                                log_warning("Invalid udev.exec-delay ignored: %s", opt + 16);
> > -                } else if (startswith(opt, "udev.event-timeout=")) {
> > -                        r = safe_atou64(opt + 19, &arg_event_timeout_usec);
> > +                                log_warning("Invalid udev.exec-delay ignored: %s", opt + strlen(name));
> > +                } else if (startswith(opt, name = "udev.event-timeout=")) {
> > +                        r = safe_atou64(opt + strlen(name), &arg_event_timeout_usec);
> >                          if (r < 0) {
> > -                                log_warning("Invalid udev.event-timeout ignored: %s", opt + 19);
> > +                                log_warning("Invalid udev.event-timeout ignored: %s", opt + strlen(name));
> >                                  break;
> >                          }
> >                          arg_event_timeout_usec *= USEC_PER_SEC;
> > --
> > 2.1.0
> >
> > _______________________________________________
> > systemd-devel mailing list
> > systemd-devel at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/systemd-devel

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