[PATCH] xfree86: Use SA_SIGINFO if available for SIGIO handlers

[Gabor Gombas]

On Tue, Nov 10, 2009 at 02:53:50PM -0500, Adam Jackson wrote:

> +#else /* have SA_SIGINFO */
> +
> +/* siginfo passes the triggering fd in, no need to select() */
> +static void
> +sigio_sigaction(int sig, siginfo_t *si, void *ctx)
> +{
> +    int i;
> +    int save_errno = errno;
> +
> +    for (i = 0; i < MAX_FUNCS; i++) {
> +        if (xf86SigIOFuncs[i].f && xf86SigIOFuncs[i].fd == si->si_fd) {
> +            (*xf86SigIOFuncs[i].f)(si->si_fd, xf86SigIOFuncs[i].closure);
> +            break;
> +        }
> +    }
> +
> +    errno = save_errno;
> +}
> +
> +#endif

For completeness sake you should check that si->si_code == SI_SIGIO
before using si->si_fd, according to the fcntl(2) man page. si->si_fd
may be undefined if someone does a "kill -SIGIO <pid of xserver>" for
whatever reason.

Gabor

-- 
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     MTA SZTAKI Computer and Automation Research Institute
                Hungarian Academy of Sciences
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