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

   1 /* read_switch.c -- prompt the user for an answer from the list
   2  *
   3  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   4  * COPYRIGHT file in the root directory of the nmh distribution for
   5  * complete copyright information.
   6  */
   7
   8 #include "h/mh.h"
   9 #include "smatch.h"
  10
  11
  12 int
  13 read_switch (const char *prompt, const struct swit *ansp)
  14 {
  15     int i;
  16     char *cp;
  17     const struct swit *ap;
  18     char ansbuf[BUFSIZ];
  19
  20     for (;;) {
  21         fputs(prompt, stdout);
  22         fflush (stdout);
  23         cp = ansbuf;
  24         while ((i = getchar ()) != '\n') {
  25             if (i == EOF)
  26                 return 0;
  27             if (cp < &ansbuf[sizeof ansbuf - 1]) {
  28                 i = tolower(i);
  29                 *cp++ = i;
  30             }
  31         }
  32         *cp = '\0';
  33         if (ansbuf[0] == '?' || cp == ansbuf) {
  34             puts("Options are:");
  35             for (ap = ansp; ap->sw; ap++)
  36                 printf ("  %s\n", ap->sw);
  37             continue;
  38         }
  39         if ((i = smatch (ansbuf, ansp)) < 0) {
  40             printf ("%s: %s.\n", ansbuf, i == -1 ? "unknown" : "ambiguous");
  41             continue;
  42         }
  43         return i;
  44     }
  45 }