signal() and Solaris 2.x

signal() is not reliable under Solaris 2.x (or any other SYSV based OS, for
that matter). On these OSes, squid should be using sigaction() (actually,
sigaction should be preferred on any POSIX OS). I've hacked it into my
source using the following header file, but it should be changed in the
distribution.

--
Carson Gaspar -- carson@cs.columbia.edu carson@lehman.com
http://www.cs.columbia.edu/~carson/home.html
<This is the boring business .sig - no outre sayings here>
/* BSD -> POSIX signal macros. Version 1.0
   Written by Carson Gaspar (carson@lehman.com, carson@cs.columbia.edu)
   Permission is hereby granted to use them in any way as long as credit
   is given to the author. */
 
/* assume signal.h is protected against multiple inclusion */
#include <signal.h>
static struct sigaction _fixsig_sa_act, _fixsig_sa_oact;
static sigset_t _fixsig_sigset;
#define signal(s,f)                     \
  (_fixsig_sa_act.sa_handler = (f),             \
   sigemptyset(&_fixsig_sa_act.sa_mask),        \
   _fixsig_sa_act.sa_flags |= (s == SIGALRM ? 0 : SA_RESTART), \
   sigaction((s), &_fixsig_sa_act, &_fixsig_sa_oact),   \
   _fixsig_sa_oact.sa_handler)
#define sigmask(x) (1<<(x))
 
/* WARNING! This grovels about in the sigset structure. It works under
   Solaris 2.[345], but Your Mileage May Vary */
 
#define _mask_to_sigset(x) (sigemptyset(&_fixsig_sigset),_fixsig_sigset.__sigbits[0] |= x)
#define sigsetmask(x) (_mask_to_sigset(x),sigprocmask(SIG_SETMASK,&_fixsig_sigset,NULL))
#define sigblock(x) (_mask_to_sigset(x),sigprocmask(SIG_BLOCK,&_fixsig_sigset,0))
#define sighold(x) (_mask_to_sigset(sigmask(x)),sigprocmask(SIG_BLOCK,&_fixsig_sigset,0))
#define sigrelse(x) (_mask_to_sigset(sigmask(x)),sigprocmask(SIG_UNBLOCK,&_fixsig_sigset,0))
#define sigignore(x) signal(x,SIG_IGN)
#define sigpause(x) (sigprocmask(0,0,&_fixsig_sigset),sigdelset(&_fixsig_sigset,x),sigsuspend(&_fixsig_sigset))