larn/signal.c

   1 #ifndef lint
   2 static char rcsid[] = "$Id: signal.c,v 1.2 1993/08/02 17:20:21 mycroft Exp $";
   3 #endif /* not lint */
   4
   5 #include <signal.h>
   6 #include "header.h"                     /* "Larn is copyrighted 1986 by Noah Morgan.\n" */
   7 #define BIT(a) (1<<((a)-1))
   8 extern char savefilename[],wizard,predostuff,nosignal;
   9 static s2choose()       /* text to be displayed if ^C during intro screen */
  10         {
  11         cursor(1,24); lprcat("Press "); setbold(); lprcat("return"); resetbold();
  12         lprcat(" to continue: ");   lflush();
  13         }
  14
  15 static void
  16 cntlc() /* what to do for a ^C */
  17         {
  18         if (nosignal) return;   /* don't do anything if inhibited */
  19         signal(SIGQUIT,SIG_IGN);        signal(SIGINT,SIG_IGN);
  20         quit(); if (predostuff==1) s2choose(); else showplayer();
  21         lflush();
  22         signal(SIGQUIT,cntlc);  signal(SIGINT,cntlc);
  23         }
  24
  25 /*
  26  *      subroutine to save the game if a hangup signal
  27  */
  28 static void
  29 sgam()
  30         {
  31         savegame(savefilename);  wizard=1;  died(-257); /* hangup signal */
  32         }
  33
  34 #ifdef SIGTSTP
  35 static void
  36 tstop() /* control Y    */
  37         {
  38         if (nosignal)   return;  /* nothing if inhibited */
  39         lcreat((char*)0);  clearvt100();        lflush();         signal(SIGTSTP,SIG_DFL);
  40 #ifdef SIGVTALRM
  41         /* looks like BSD4.2 or higher - must clr mask for signal to take effect*/
  42         sigsetmask(sigblock(0)& ~BIT(SIGTSTP));
  43 #endif
  44         kill(getpid(),SIGTSTP);
  45
  46         setupvt100();  signal(SIGTSTP,tstop);
  47         if (predostuff==1) s2choose(); else drawscreen();
  48         showplayer();   lflush();
  49         }
  50 #endif SIGTSTP
  51
  52 /*
  53  *      subroutine to issue the needed signal traps  called from main()
  54  */
  55 static void sigpanic();
  56 static void sigill()    { sigpanic(SIGILL); }
  57 static void sigtrap()   { sigpanic(SIGTRAP); }
  58 static void sigiot()    { sigpanic(SIGIOT); }
  59 static void sigemt()    { sigpanic(SIGEMT); }
  60 static void sigfpe()    { sigpanic(SIGFPE); }
  61 static void sigbus()    { sigpanic(SIGBUS); }
  62 static void sigsegv()   { sigpanic(SIGSEGV); }
  63 static void sigsys()    { sigpanic(SIGSYS); }
  64 static void sigpipe()   { sigpanic(SIGPIPE); }
  65 static void sigterm()   { sigpanic(SIGTERM); }
  66 sigsetup()
  67         {
  68         signal(SIGQUIT, cntlc);                 signal(SIGINT,  cntlc);
  69         signal(SIGKILL, SIG_IGN);               signal(SIGHUP,  sgam);
  70         signal(SIGILL,  sigill);                signal(SIGTRAP, sigtrap);
  71         signal(SIGIOT,  sigiot);                signal(SIGEMT,  sigemt);
  72         signal(SIGFPE,  sigfpe);                signal(SIGBUS,  sigbus);
  73         signal(SIGSEGV, sigsegv);               signal(SIGSYS,  sigsys);
  74         signal(SIGPIPE, sigpipe);               signal(SIGTERM, sigterm);
  75 #ifdef SIGTSTP
  76         signal(SIGTSTP,tstop);          signal(SIGSTOP,tstop);
  77 #endif SIGTSTP
  78         }
  79
  80 #ifdef BSD      /* for BSD UNIX? */
  81
  82 static char *signame[NSIG] = { "",
  83 "SIGHUP",  /*   1        hangup */
  84 "SIGINT",  /*   2        interrupt */
  85 "SIGQUIT", /*   3        quit */
  86 "SIGILL",  /*   4        illegal instruction (not reset when caught) */
  87 "SIGTRAP", /*   5        trace trap (not reset when caught) */
  88 "SIGIOT",  /*   6        IOT instruction */
  89 "SIGEMT",  /*   7        EMT instruction */
  90 "SIGFPE",  /*   8        floating point exception */
  91 "SIGKILL", /*   9        kill (cannot be caught or ignored) */
  92 "SIGBUS",  /*   10       bus error */
  93 "SIGSEGV", /*   11       segmentation violation */
  94 "SIGSYS",  /*   12       bad argument to system call */
  95 "SIGPIPE", /*   13       write on a pipe with no one to read it */
  96 "SIGALRM", /*   14       alarm clock */
  97 "SIGTERM", /*   15       software termination signal from kill */
  98 "SIGURG",  /*   16       urgent condition on IO channel */
  99 "SIGSTOP", /*   17       sendable stop signal not from tty */
 100 "SIGTSTP", /*   18       stop signal from tty */
 101 "SIGCONT", /*   19       continue a stopped process */
 102 "SIGCHLD", /*   20       to parent on child stop or exit */
 103 "SIGTTIN", /*   21       to readers pgrp upon background tty read */
 104 "SIGTTOU", /*   22       like TTIN for output if (tp->t_local&LTOSTOP) */
 105 "SIGIO",   /*   23       input/output possible signal */
 106 "SIGXCPU", /*   24       exceeded CPU time limit */
 107 "SIGXFSZ", /*   25       exceeded file size limit */
 108 "SIGVTALRM",/*  26       virtual time alarm */
 109 "SIGPROF", /*   27       profiling time alarm */
 110 "","","","" };
 111
 112 #else BSD       /* for system V? */
 113
 114 static char *signame[NSIG] = { "",
 115 "SIGHUP",  /*   1        hangup */
 116 "SIGINT",  /*   2        interrupt */
 117 "SIGQUIT", /*   3        quit */
 118 "SIGILL",  /*   4        illegal instruction (not reset when caught) */
 119 "SIGTRAP", /*   5        trace trap (not reset when caught) */
 120 "SIGIOT",  /*   6        IOT instruction */
 121 "SIGEMT",  /*   7        EMT instruction */
 122 "SIGFPE",  /*   8        floating point exception */
 123 "SIGKILL", /*   9        kill (cannot be caught or ignored) */
 124 "SIGBUS",  /*   10       bus error */
 125 "SIGSEGV", /*   11       segmentation violation */
 126 "SIGSYS",  /*   12       bad argument to system call */
 127 "SIGPIPE", /*   13       write on a pipe with no one to read it */
 128 "SIGALRM", /*   14       alarm clock */
 129 "SIGTERM", /*   15       software termination signal from kill */
 130 "SIGUSR1",  /*  16       user defines signal 1 */
 131 "SIGUSR2", /*   17       user defines signal 2 */
 132 "SIGCLD",  /*   18       child death */
 133 "SIGPWR",  /*   19       power fail */
 134 "","","","","","","","","","","","" };
 135
 136 #endif BSD
 137
 138 /*
 139  *      routine to process a fatal error signal
 140  */
 141 static void
 142 sigpanic(sig)
 143         int sig;
 144         {
 145         char buf[128];
 146         signal(sig,SIG_DFL);
 147         sprintf(buf,"\nLarn - Panic! Signal %d received [%s]",sig,signame[sig]);
 148         write(2,buf,strlen(buf));  sleep(2);
 149         sncbr();
 150         savegame(savefilename);
 151         kill(getpid(),sig); /* this will terminate us */
 152         }