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

   1 /* read_switch_multiword.c -- get an answer from the user and return a string array
   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 "print_sw.h"
  10 #include "h/signals.h"
  11 #include <setjmp.h>
  12
  13 static char ansbuf[BUFSIZ];
  14 static sigjmp_buf sigenv;
  15
  16 /*
  17  * static prototypes
  18  */
  19 static void intrser (int);
  20
  21
  22 char **
  23 read_switch_multiword (const char *prompt, const struct swit *ansp)
  24 {
  25     int i;
  26     SIGNAL_HANDLER istat = NULL;
  27     char *cp, **cpp;
  28
  29     if (sigsetjmp(sigenv, 1)) {
  30         SIGNAL (SIGINT, istat);
  31         return NULL;
  32     }
  33     istat = SIGNAL (SIGINT, intrser);
  34
  35     for (;;) {
  36         fputs(prompt, stdout);
  37         fflush (stdout);
  38         cp = ansbuf;
  39         while ((i = getchar ()) != '\n') {
  40             if (i == EOF) {
  41                 /*
  42                  * If we get an EOF, return
  43                  */
  44                 if (feof(stdin))
  45                     siglongjmp (sigenv, 1);
  46
  47                 /*
  48                  * For errors, if we get an EINTR that means that we got
  49                  * a signal and we should retry.  If we get another error,
  50                  * then just return.
  51                  */
  52
  53                 if (ferror(stdin)) {
  54                     if (errno == EINTR) {
  55                         clearerr(stdin);
  56                         continue;
  57                     }
  58                     fprintf(stderr, "\nError %s during read\n",
  59                             strerror(errno));
  60                     siglongjmp (sigenv, 1);
  61                 }
  62
  63                 /* Just for completeness's sake... */
  64                 fprintf(stderr, "\nUnknown problem in getchar()\n");
  65                 siglongjmp(sigenv, 1);
  66             }
  67             if (cp < &ansbuf[sizeof ansbuf - 1])
  68                 *cp++ = i;
  69         }
  70         *cp = '\0';
  71         if (ansbuf[0] == '?' || cp == ansbuf) {
  72             puts("Options are:");
  73             print_sw (ALL, ansp, "", stdout);
  74             continue;
  75         }
  76         cpp = brkstring (ansbuf, " ", NULL);
  77         switch (smatch (*cpp, ansp)) {
  78             case AMBIGSW:
  79                 ambigsw (*cpp, ansp);
  80                 continue;
  81             case UNKWNSW:
  82                 printf (" -%s unknown. Hit <CR> for help.\n", *cpp);
  83                 continue;
  84             default:
  85                 SIGNAL (SIGINT, istat);
  86                 return cpp;
  87         }
  88     }
  89 }
  90
  91
  92 static void
  93 intrser (int i)
  94 {
  95     NMH_UNUSED (i);
  96
  97     siglongjmp (sigenv, 1);
  98 }