diplodocus.org Git - nmh/blob - sbr/getans.c

   1
   2 /*
   3  * getans.c -- get an answer from the user and return a string array
   4  *
   5  * $Id$
   6  */
   7
   8 #include <h/mh.h>
   9 #include <h/signals.h>
  10 #include <setjmp.h>
  11 #include <signal.h>
  12
  13 static char ansbuf[BUFSIZ];
  14 static jmp_buf sigenv;
  15
  16 /*
  17  * static prototypes
  18  */
  19 static RETSIGTYPE intrser (int);
  20
  21
  22 char **
  23 getans (char *prompt, struct swit *ansp)
  24 {
  25     int i;
  26     SIGNAL_HANDLER istat;
  27     char *cp, **cpp;
  28
  29     if (!(setjmp (sigenv))) {
  30         istat = SIGNAL (SIGINT, intrser);
  31     } else {
  32         SIGNAL (SIGINT, istat);
  33         return NULL;
  34     }
  35
  36     for (;;) {
  37         printf ("%s", prompt);
  38         fflush (stdout);
  39         cp = ansbuf;
  40         while ((i = getchar ()) != '\n') {
  41             if (i == EOF)
  42                 longjmp (sigenv, 1);
  43             if (cp < &ansbuf[sizeof ansbuf - 1])
  44                 *cp++ = i;
  45         }
  46         *cp = '\0';
  47         if (ansbuf[0] == '?' || cp == ansbuf) {
  48             printf ("Options are:\n");
  49             print_sw (ALL, ansp, "");
  50             continue;
  51         }
  52         cpp = brkstring (ansbuf, " ", NULL);
  53         switch (smatch (*cpp, ansp)) {
  54             case AMBIGSW:
  55                 ambigsw (*cpp, ansp);
  56                 continue;
  57             case UNKWNSW:
  58                 printf (" -%s unknown. Hit <CR> for help.\n", *cpp);
  59                 continue;
  60             default:
  61                 SIGNAL (SIGINT, istat);
  62                 return cpp;
  63         }
  64     }
  65 }
  66
  67
  68 static RETSIGTYPE
  69 intrser (int i)
  70 {
  71     /*
  72      * should this be siglongjmp?
  73      */
  74     longjmp (sigenv, 1);
  75 }