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  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   8  * COPYRIGHT file in the root directory of the nmh distribution for
   9  * complete copyright information.
  10  */
  11
  12 #include <h/mh.h>
  13 #include <h/signals.h>
  14 #include <setjmp.h>
  15 #include <signal.h>
  16
  17 static char ansbuf[BUFSIZ];
  18 static jmp_buf sigenv;
  19
  20 /*
  21  * static prototypes
  22  */
  23 static RETSIGTYPE intrser (int);
  24
  25
  26 char **
  27 getans (char *prompt, struct swit *ansp)
  28 {
  29     int i;
  30     SIGNAL_HANDLER istat;
  31     char *cp, **cpp;
  32
  33     if (!(setjmp (sigenv))) {
  34         istat = SIGNAL (SIGINT, intrser);
  35     } else {
  36         SIGNAL (SIGINT, istat);
  37         return NULL;
  38     }
  39
  40     for (;;) {
  41         printf ("%s", prompt);
  42         fflush (stdout);
  43         cp = ansbuf;
  44         while ((i = getchar ()) != '\n') {
  45             if (i == EOF)
  46                 longjmp (sigenv, 1);
  47             if (cp < &ansbuf[sizeof ansbuf - 1])
  48                 *cp++ = i;
  49         }
  50         *cp = '\0';
  51         if (ansbuf[0] == '?' || cp == ansbuf) {
  52             printf ("Options are:\n");
  53             print_sw (ALL, ansp, "");
  54             continue;
  55         }
  56         cpp = brkstring (ansbuf, " ", NULL);
  57         switch (smatch (*cpp, ansp)) {
  58             case AMBIGSW:
  59                 ambigsw (*cpp, ansp);
  60                 continue;
  61             case UNKWNSW:
  62                 printf (" -%s unknown. Hit <CR> for help.\n", *cpp);
  63                 continue;
  64             default:
  65                 SIGNAL (SIGINT, istat);
  66                 return cpp;
  67         }
  68     }
  69 }
  70
  71
  72 static RETSIGTYPE
  73 intrser (int i)
  74 {
  75     /*
  76      * should this be siglongjmp?
  77      */
  78     longjmp (sigenv, 1);
  79 }