/*      $NetBSD: unvis.c,v 1.13 2010/11/27 19:46:25 christos Exp $      */

/*-
* Copyright (c) 1989, 1993
*      The Regents of the University of California.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1989, 1993\
The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)unvis.c     8.1 (Berkeley) 6/6/93";
#endif
__RCSID("$NetBSD: unvis.c,v 1.13 2010/11/27 19:46:25 christos Exp $");
#endif /* not lint */

#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <vis.h>

static void process(FILE *, const char *, int);

int
main(int argc, char *argv[])
{
       FILE *fp;
       int ch, eflags = 0;

       setprogname(argv[0]);
       while ((ch = getopt(argc, argv, "eHhm")) != -1)
               switch((char)ch) {
               case 'e':
                       eflags |= VIS_NOESCAPE;
                       break;
               case 'H':
                       eflags |= VIS_HTTP1866;
                       break;
               case 'h':
                       eflags |= VIS_HTTP1808;
                       break;
               case 'm':
                       eflags |= VIS_MIMESTYLE;
                       break;
               case '?':
               default:
                       (void)fprintf(stderr,
                           "Usage: %s [-e] [-Hh | -m] [file...]\n",
                           getprogname());
                       return EXIT_FAILURE;
               }
       argc -= optind;
       argv += optind;

       switch (eflags & (VIS_HTTP1808|VIS_HTTP1866|VIS_MIMESTYLE)) {
       case VIS_HTTP1808|VIS_MIMESTYLE:
       case VIS_HTTP1866|VIS_MIMESTYLE:
       case VIS_HTTP1808|VIS_HTTP1866|VIS_MIMESTYLE:
               errx(EXIT_FAILURE, "Can't mix -m with -h and/or -H");
               /*NOTREACHED*/
       default:
               break;
       }

       if (*argv)
               while (*argv) {
                       if ((fp = fopen(*argv, "r")) != NULL)
                               process(fp, *argv, eflags);
                       else
                               warn("%s", *argv);
                       argv++;
               }
       else
               process(stdin, "<stdin>", eflags);
       return EXIT_SUCCESS;
}

static void
process(FILE *fp, const char *filename, int eflags)
{
       int offset = 0, c, ret;
       int state = 0;
       char outc;

       while ((c = getc(fp)) != EOF) {
               offset++;
       again:
               switch(ret = unvis(&outc, (char)c, &state, eflags)) {
               case UNVIS_VALID:
                       (void)putchar(outc);
                       break;
               case UNVIS_VALIDPUSH:
                       (void)putchar(outc);
                       goto again;
               case UNVIS_SYNBAD:
                       warnx("%s: offset: %d: can't decode", filename, offset);
                       state = 0;
                       break;
               case 0:
               case UNVIS_NOCHAR:
                       break;
               default:
                       errx(1, "bad return value (%d), can't happen", ret);
                       /* NOTREACHED */
               }
       }
       if (unvis(&outc, (char)0, &state, eflags | UNVIS_END) == UNVIS_VALID)
               (void)putchar(outc);
}