larn/signal.c

   1 /*      $NetBSD: signal.c,v 1.9 2012/06/19 05:30:44 dholland Exp $      */
   2
   3 /* "Larn is copyrighted 1986 by Noah Morgan.\n" */
   4
   5 #include <sys/cdefs.h>
   6 #ifndef lint
   7 __RCSID("$NetBSD: signal.c,v 1.9 2012/06/19 05:30:44 dholland Exp $");
   8 #endif  /* not lint */
   9
  10 #include <signal.h>
  11 #include <stdio.h>
  12 #include <string.h>
  13 #include <unistd.h>
  14 #include "header.h"
  15 #include "extern.h"
  16
  17 static void s2choose(void);
  18 static void cntlc(int);
  19 static void sgam(int);
  20 static void tstop(int);
  21 static void sigpanic(int);
  22
  23 #define BIT(a) (1<<((a)-1))
  24
  25 static void
  26 s2choose(void)
  27 {                               /* text to be displayed if ^C during intro
  28                                  * screen */
  29         cursor(1, 24);
  30         lprcat("Press ");
  31         setbold();
  32         lprcat("return");
  33         resetbold();
  34         lprcat(" to continue: ");
  35         lflush();
  36 }
  37
  38 static void
  39 cntlc(int n)
  40 {                               /* what to do for a ^C */
  41         if (nosignal)
  42                 return;         /* don't do anything if inhibited */
  43         signal(SIGQUIT, SIG_IGN);
  44         signal(SIGINT, SIG_IGN);
  45         quit();
  46         if (predostuff == 1)
  47                 s2choose();
  48         else
  49                 showplayer();
  50         lflush();
  51         signal(SIGQUIT, cntlc);
  52         signal(SIGINT, cntlc);
  53 }
  54
  55 /*
  56  *      subroutine to save the game if a hangup signal
  57  */
  58 static void
  59 sgam(int n)
  60 {
  61         savegame(savefilename);
  62         wizard = 1;
  63         died(-257);             /* hangup signal */
  64 }
  65
  66 #ifdef SIGTSTP
  67 static void
  68 tstop(int n)
  69 {                               /* control Y     */
  70         if (nosignal)
  71                 return;         /* nothing if inhibited */
  72         lcreat((char *) 0);
  73         clearvt100();
  74         lflush();
  75         signal(SIGTSTP, SIG_DFL);
  76 #ifdef SIGVTALRM
  77         /*
  78          * looks like BSD4.2 or higher - must clr mask for signal to take
  79          * effect
  80          */
  81         sigsetmask(sigblock(0) & ~BIT(SIGTSTP));
  82 #endif
  83         kill(getpid(), SIGTSTP);
  84
  85         setupvt100();
  86         signal(SIGTSTP, tstop);
  87         if (predostuff == 1)
  88                 s2choose();
  89         else
  90                 drawscreen();
  91         showplayer();
  92         lflush();
  93 }
  94 #endif  /* SIGTSTP */
  95
  96 /*
  97  *      subroutine to issue the needed signal traps  called from main()
  98  */
  99 void
 100 sigsetup(void)
 101 {
 102         signal(SIGQUIT, cntlc);
 103         signal(SIGINT, cntlc);
 104         signal(SIGKILL, SIG_IGN);
 105         signal(SIGHUP, sgam);
 106         signal(SIGILL, sigpanic);
 107         signal(SIGTRAP, sigpanic);
 108         signal(SIGIOT, sigpanic);
 109         signal(SIGEMT, sigpanic);
 110         signal(SIGFPE, sigpanic);
 111         signal(SIGBUS, sigpanic);
 112         signal(SIGSEGV, sigpanic);
 113         signal(SIGSYS, sigpanic);
 114         signal(SIGPIPE, sigpanic);
 115         signal(SIGTERM, sigpanic);
 116 #ifdef SIGTSTP
 117         signal(SIGTSTP, tstop);
 118         signal(SIGSTOP, tstop);
 119 #endif  /* SIGTSTP */
 120 }
 121
 122 /*
 123  *      routine to process a fatal error signal
 124  */
 125 static void
 126 sigpanic(int sig)
 127 {
 128         char            buf[128];
 129         signal(sig, SIG_DFL);
 130         snprintf(buf, sizeof(buf),
 131             "\nLarn - Panic! Signal %d received [SIG%s]", sig,
 132             sys_signame[sig]);
 133         write(2, buf, strlen(buf));
 134         sleep(2);
 135         sncbr();
 136         savegame(savefilename);
 137         kill(getpid(), sig);    /* this will terminate us */
 138 }