Re: [PATCH v2 2/4] linux-user: cleanup signal.c

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 2/4/20 6:10 PM, Laurent Vivier wrote:
> No functional changes. Prepare the field for future fixes.
> 
> Remove memset(.., 0, ...) that is useless on a static array
> 
> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
> ---
> 
> Notes:
>      v2: replace i, j by target_sig, host_sig
> 
>   linux-user/signal.c | 48 ++++++++++++++++++++++++++-------------------
>   1 file changed, 28 insertions(+), 20 deletions(-)
> 
> diff --git a/linux-user/signal.c b/linux-user/signal.c
> index 5ca6d62b15d3..246315571c09 100644
> --- a/linux-user/signal.c
> +++ b/linux-user/signal.c
> @@ -66,12 +66,6 @@ static uint8_t host_to_target_signal_table[_NSIG] = {
>       [SIGPWR] = TARGET_SIGPWR,
>       [SIGSYS] = TARGET_SIGSYS,
>       /* next signals stay the same */
> -    /* Nasty hack: Reverse SIGRTMIN and SIGRTMAX to avoid overlap with
> -       host libpthread signals.  This assumes no one actually uses SIGRTMAX :-/
> -       To fix this properly we need to do manual signal delivery multiplexed
> -       over a single host signal.  */
> -    [__SIGRTMIN] = __SIGRTMAX,
> -    [__SIGRTMAX] = __SIGRTMIN,
>   };
>   static uint8_t target_to_host_signal_table[_NSIG];
>   
> @@ -480,31 +474,45 @@ static int core_dump_signal(int sig)
>       }
>   }
>   
> +static void signal_table_init(void)
> +{
> +    int host_sig, target_sig;
> +
> +    /*
> +     * Nasty hack: Reverse SIGRTMIN and SIGRTMAX to avoid overlap with
> +     * host libpthread signals.  This assumes no one actually uses SIGRTMAX :-/
> +     * To fix this properly we need to do manual signal delivery multiplexed
> +     * over a single host signal.
> +     */
> +    host_to_target_signal_table[__SIGRTMIN] = __SIGRTMAX;
> +    host_to_target_signal_table[__SIGRTMAX] = __SIGRTMIN;
> +
> +    /* generate signal conversion tables */
> +    for (host_sig = 1; host_sig < _NSIG; host_sig++) {
> +        if (host_to_target_signal_table[host_sig] == 0) {
> +            host_to_target_signal_table[host_sig] = host_sig;
> +        }
> +    }
> +    for (host_sig = 1; host_sig < _NSIG; host_sig++) {
> +        target_sig = host_to_target_signal_table[host_sig];
> +        target_to_host_signal_table[target_sig] = host_sig;
> +    }
> +}
> +
>   void signal_init(void)
>   {
>       TaskState *ts = (TaskState *)thread_cpu->opaque;
>       struct sigaction act;
>       struct sigaction oact;
> -    int i, j;
> +    int i;
>       int host_sig;
>   
> -    /* generate signal conversion tables */
> -    for(i = 1; i < _NSIG; i++) {
> -        if (host_to_target_signal_table[i] == 0)
> -            host_to_target_signal_table[i] = i;
> -    }
> -    for(i = 1; i < _NSIG; i++) {
> -        j = host_to_target_signal_table[i];
> -        target_to_host_signal_table[j] = i;
> -    }
> +    /* initialize signal conversion tables */
> +    signal_table_init();
>   
>       /* Set the signal mask from the host mask. */
>       sigprocmask(0, 0, &ts->signal_mask);
>   
> -    /* set all host signal handlers. ALL signals are blocked during
> -       the handlers to serialize them. */
> -    memset(sigact_table, 0, sizeof(sigact_table));
> -
>       sigfillset(&act.sa_mask);
>       act.sa_flags = SA_SIGINFO;
>       act.sa_sigaction = host_signal_handler;
> 

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>