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