Re: RFC: sigaction module

[Bruno Haible]

Eric Blake wrote:
> Your review hopefully made it even better.

Thanks for addressing all the issues. And thanks for noticing the
missing reloading of the handler in blocking_handler.

> OK, the version of the patch posted below should be safer in the presence of 
> async signals (it will never be perfect, due to mingw's inherent data race 
> caused by the temporary uninstallation of a handler, as well as its inability 
> to atomically block signals).

Yes, I don't see workarounds for these two problems either,

An additional commit:
In lib/nanosleep.c there is no need to set up the newact variable in the
case when it is not used.


2008-06-22  Bruno Haible  <address@hidden>

        * lib/nanosleep.c (rpl_nanosleep): Setup newact only when it is needed.

*** lib/nanosleep.c.orig        2008-06-22 21:32:31.000000000 +0200
--- lib/nanosleep.c     2008-06-22 21:32:24.000000000 +0200
***************
*** 147,160 ****
    /* set up sig handler */
    if (! initialized)
      {
!       struct sigaction oldact, newact;
!       newact.sa_handler = sighandler;
!       sigemptyset (&newact.sa_mask);
!       newact.sa_flags = 0;
  
        sigaction (SIGCONT, NULL, &oldact);
        if (get_handler (&oldact) != SIG_IGN)
!       sigaction (SIGCONT, &newact, NULL);
        initialized = true;
      }
  
--- 147,164 ----
    /* set up sig handler */
    if (! initialized)
      {
!       struct sigaction oldact;
  
        sigaction (SIGCONT, NULL, &oldact);
        if (get_handler (&oldact) != SIG_IGN)
!       {
!         struct sigaction newact;
! 
!         newact.sa_handler = sighandler;
!         sigemptyset (&newact.sa_mask);
!         newact.sa_flags = 0;
!         sigaction (SIGCONT, &newact, NULL);
!       }
        initialized = true;
      }