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