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 "read_switch_multiword.h"
  10 #include "smatch.h"
  11 #include "brkstring.h"
  12 #include "ambigsw.h"
  13 #include "print_sw.h"
  14 #include "h/signals.h"
  15 #include <setjmp.h>
  16
  17 static char ansbuf[BUFSIZ];
  18 static sigjmp_buf sigenv;
  19
  20 /*
  21  * static prototypes
  22  */
  23 static void intrser (int);
  24
  25
  26 char **
  27 read_switch_multiword (const char *prompt, const struct swit *ansp)
  28 {
  29     int i;
  30     SIGNAL_HANDLER istat = NULL;
  31     char *cp, **cpp;
  32
  33     if (sigsetjmp(sigenv, 1)) {
  34         SIGNAL (SIGINT, istat);
  35         return NULL;
  36     }
  37     istat = SIGNAL (SIGINT, intrser);
  38
  39     for (;;) {
  40         fputs(prompt, stdout);
  41         fflush (stdout);
  42         cp = ansbuf;
  43         while ((i = getchar ()) != '\n') {
  44             if (i == EOF) {
  45                 /*
  46                  * If we get an EOF, return
  47                  */
  48                 if (feof(stdin))
  49                     siglongjmp (sigenv, 1);
  50
  51                 /*
  52                  * For errors, if we get an EINTR that means that we got
  53                  * a signal and we should retry.  If we get another error,
  54                  * then just return.
  55                  */
  56
  57                 if (ferror(stdin)) {
  58                     if (errno == EINTR) {
  59                         clearerr(stdin);
  60                         continue;
  61                     }
  62                     fprintf(stderr, "\nError %s during read\n",
  63                             strerror(errno));
  64                     siglongjmp (sigenv, 1);
  65                 }
  66
  67                 /* Just for completeness's sake... */
  68                 fprintf(stderr, "\nUnknown problem in getchar()\n");
  69                 siglongjmp(sigenv, 1);
  70             }
  71             if (cp < &ansbuf[sizeof ansbuf - 1])
  72                 *cp++ = i;
  73         }
  74         *cp = '\0';
  75         if (ansbuf[0] == '?' || cp == ansbuf) {
  76             puts("Options are:");
  77             print_sw (ALL, ansp, "", stdout);
  78             continue;
  79         }
  80         cpp = brkstring (ansbuf, " ", NULL);
  81         switch (smatch (*cpp, ansp)) {
  82             case AMBIGSW:
  83                 ambigsw (*cpp, ansp);
  84                 continue;
  85             case UNKWNSW:
  86                 printf (" -%s unknown. Hit <CR> for help.\n", *cpp);
  87                 continue;
  88             default:
  89                 SIGNAL (SIGINT, istat);
  90                 return cpp;
  91         }
  92     }
  93 }
  94
  95
  96 static void
  97 intrser (int i)
  98 {
  99     NMH_UNUSED (i);
 100
 101     siglongjmp (sigenv, 1);
 102 }