games/larn/signal.c

   1 /* "Larn is copyrighted 1986 by Noah Morgan.\n" */
   2
   3 #include <signal.h>
   4 #include "header.h"
   5
   6 static void s2choose(void);
   7 static void cntlc(int);
   8 static void sgam(int);
   9 #ifdef SIGTSTP
  10 static void tstop(int);
  11 #endif
  12 static void sigill(int);
  13 static void sigtrap(int);
  14 static void sigiot(int);
  15 static void sigemt(int);
  16 static void sigfpe(int);
  17 static void sigbus(int);
  18 static void sigsegv(int);
  19 static void sigsys(int);
  20 static void sigpipe(int);
  21 static void sigterm(int);
  22 static void sigpanic(int);
  23
  24 #define BIT(a) (1<<((a)-1))
  25
  26 static void
  27 s2choose(void)  /* text to be displayed if ^C during intro screen */
  28 {
  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(__unused int sig) /* what to do for a ^C */
  40 {
  41         if (nosignal)   /* don't do anything if inhibited */
  42                 return;
  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(__unused int sig)
  60 {
  61         savegame(savefilename);
  62         wizard = 1;
  63         died(-257);             /* hangup signal */
  64 }
  65
  66 #ifdef SIGTSTP
  67 static void
  68 tstop(__unused int sig) /* control Y */
  69 {
  70         if (nosignal)           /* nothing if inhibited */
  71                 return;
  72         lcreat(NULL);
  73         clearvt100();
  74         lflush();
  75         signal(SIGTSTP, SIG_DFL);
  76 #ifdef SIGVTALRM
  77         /* looks like BSD4.2 or higher - must clr mask for signal to take effect*/
  78         sigsetmask(sigblock(0) & ~BIT(SIGTSTP));
  79 #endif
  80         kill(getpid(), SIGTSTP);
  81
  82         setupvt100();
  83         signal(SIGTSTP, tstop);
  84         if (predostuff == 1)
  85                 s2choose();
  86         else
  87                 drawscreen();
  88         showplayer();
  89         lflush();
  90 }
  91 #endif /* SIGTSTP */
  92
  93 /*
  94  *      subroutine to issue the needed signal traps  called from main()
  95  */
  96 static void
  97 sigill(__unused int sig)
  98 {
  99         sigpanic(SIGILL);
 100 }
 101
 102 static void
 103 sigtrap(__unused int sig)
 104 {
 105         sigpanic(SIGTRAP);
 106 }
 107
 108 static void
 109 sigiot(__unused int sig)
 110 {
 111         sigpanic(SIGIOT);
 112 }
 113
 114 static void
 115 sigemt(__unused int sig)
 116 {
 117         sigpanic(SIGEMT);
 118 }
 119
 120 static void
 121 sigfpe(__unused int sig)
 122 {
 123         sigpanic(SIGFPE);
 124 }
 125
 126 static void
 127 sigbus(__unused int sig)
 128 {
 129         sigpanic(SIGBUS);
 130 }
 131
 132 static void
 133 sigsegv(__unused int sig)
 134 {
 135         sigpanic(SIGSEGV);
 136 }
 137
 138 static void
 139 sigsys(__unused int sig)
 140 {
 141         sigpanic(SIGSYS);
 142 }
 143
 144 static void
 145 sigpipe(__unused int sig)
 146 {
 147         sigpanic(SIGPIPE);
 148 }
 149
 150 static void
 151 sigterm(__unused int sig)
 152 {
 153         sigpanic(SIGTERM);
 154 }
 155
 156 void
 157 sigsetup(void)
 158 {
 159         signal(SIGQUIT, cntlc);
 160         signal(SIGINT, cntlc);
 161         signal(SIGKILL, SIG_IGN);
 162         signal(SIGHUP, sgam);
 163         signal(SIGILL, sigill);
 164         signal(SIGTRAP, sigtrap);
 165         signal(SIGIOT, sigiot);
 166         signal(SIGEMT, sigemt);
 167         signal(SIGFPE, sigfpe);
 168         signal(SIGBUS, sigbus);
 169         signal(SIGSEGV, sigsegv);
 170         signal(SIGSYS, sigsys);
 171         signal(SIGPIPE, sigpipe);
 172         signal(SIGTERM, sigterm);
 173 #ifdef SIGTSTP
 174         signal(SIGTSTP, tstop);
 175         signal(SIGSTOP, tstop);
 176 #endif /* SIGTSTP */
 177 }
 178
 179 static const char *signame[NSIG] = { "",
 180 "SIGHUP",  /*   1       hangup */
 181 "SIGINT",  /*   2       interrupt */
 182 "SIGQUIT", /*   3       quit */
 183 "SIGILL",  /*   4       illegal instruction (not reset when caught) */
 184 "SIGTRAP", /*   5       trace trap (not reset when caught) */
 185 "SIGIOT",  /*   6       IOT instruction */
 186 "SIGEMT",  /*   7       EMT instruction */
 187 "SIGFPE",  /*   8       floating point exception */
 188 "SIGKILL", /*   9       kill (cannot be caught or ignored) */
 189 "SIGBUS",  /*  10       bus error */
 190 "SIGSEGV", /*  11       segmentation violation */
 191 "SIGSYS",  /*  12       bad argument to system call */
 192 "SIGPIPE", /*  13       write on a pipe with no one to read it */
 193 "SIGALRM", /*  14       alarm clock */
 194 "SIGTERM", /*  15       software termination signal from kill */
 195 "SIGURG",  /*  16       urgent condition on IO channel */
 196 "SIGSTOP", /*  17       sendable stop signal not from tty */
 197 "SIGTSTP", /*  18       stop signal from tty */
 198 "SIGCONT", /*  19       continue a stopped process */
 199 "SIGCHLD", /*  20       to parent on child stop or exit */
 200 "SIGTTIN", /*  21       to readers pgrp upon background tty read */
 201 "SIGTTOU", /*  22       like TTIN for output if (tp->t_local&LTOSTOP) */
 202 "SIGIO",   /*  23       input/output possible signal */
 203 "SIGXCPU", /*  24       exceeded CPU time limit */
 204 "SIGXFSZ", /*  25       exceeded file size limit */
 205 "SIGVTALRM",/* 26       virtual time alarm */
 206 "SIGPROF", /*  27       profiling time alarm */
 207 "SIGWINCH",/*  28       window size changes */
 208 "SIGINFO", /*  29       information request */
 209 "SIGUSR1", /*  30       user defined signal 1 */
 210 "SIGUSR2", /*  31       user defined signal 2 */
 211 };
 212
 213 /*
 214  *      routine to process a fatal error signal
 215  */
 216 static void
 217 sigpanic(int sig)
 218 {
 219         char buf[128];
 220         signal(sig, SIG_DFL);
 221         sprintf(buf, "\nLarn - Panic! Signal %d received [%s]", sig, signame[sig]);
 222         write(2, buf, strlen(buf));
 223         sleep(2);
 224         sncbr();
 225         savegame(savefilename);
 226         kill(getpid(), sig);    /* this will terminate us */
 227 }