/*      $OpenBSD: vis.c,v 1.22 2022/12/04 23:50:50 cheloha Exp $        */
/*      $NetBSD: vis.c,v 1.4 1994/12/20 16:13:03 jtc 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 <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <limits.h>
#include <err.h>
#include <vis.h>

int eflags, fold, foldwidth=80, none, markeol;

#ifdef DEBUG
int debug;
#endif

int foldit(char *, int, int);
void process(FILE *);
__dead void usage(void);

int
main(int argc, char *argv[])
{
        const char *errstr;
        FILE *fp;
        int ch;

        if (pledge("stdio rpath", NULL) == -1)
                err(1, "pledge");

        while ((ch = getopt(argc, argv, "anwctsobfF:ld")) != -1)
                switch(ch) {
                case 'a':
                        eflags |= VIS_ALL;
                        break;
                case 'n':
                        none = 1;
                        break;
                case 'w':
                        eflags |= VIS_WHITE;
                        break;
                case 'c':
                        eflags |= VIS_CSTYLE;
                        break;
                case 't':
                        eflags |= VIS_TAB;
                        break;
                case 's':
                        eflags |= VIS_SAFE;
                        break;
                case 'o':
                        eflags |= VIS_OCTAL;
                        break;
                case 'b':
                        eflags |= VIS_NOSLASH;
                        break;
                case 'F':
                        foldwidth = strtonum(optarg, 1, INT_MAX, &errstr);
                        if (errstr)
                                errx(1, "%s: %s", optarg, errstr);
                        if (foldwidth < 5)
                                errx(1, "can't fold lines to less than 5 cols");
                        /*FALLTHROUGH*/
                case 'f':
                        fold = 1;       /* fold output lines to 80 cols */
                        break;          /* using hidden newline */
                case 'l':
                        markeol = 1;    /* mark end of line with \$ */
                        break;
#ifdef DEBUG
                case 'd':
                        debug = 1;
                        break;
#endif
                default:
                        usage();
                }
        argc -= optind;
        argv += optind;

        if (*argv)
                while (*argv) {
                        if ((fp=fopen(*argv, "r")) != NULL) {
                                process(fp);
                                fclose(fp);
                        } else
                                warn("%s", *argv);
                        argv++;
                }
        else {
                if (pledge("stdio", NULL) == -1)
                        err(1, "pledge");
                process(stdin);
        }
        exit(0);
}
        
void
process(FILE *fp)
{
        static int col = 0;
        char *cp = "\0";
        int c, rachar; 
        char buff[5];
        
        cp++;                   /* so *(cp-1) starts out != '\n' */
        c = getc(fp);
        while (c != EOF) {
                rachar = getc(fp);
                if (none) {
                        cp = buff;
                        *cp++ = c;
                        if (c == '\\')
                                *cp++ = '\\';
                        *cp = '\0';
                } else if (markeol && c == '\n') {
                        cp = buff;
                        if ((eflags & VIS_NOSLASH) == 0)
                                *cp++ = '\\';
                        *cp++ = '$';
                        *cp++ = '\n';
                        *cp = '\0';
                } else 
                        (void) vis(buff, (char)c, eflags, (char)rachar);

                cp = buff;
                if (fold) {
#ifdef DEBUG
                        if (debug)
                                printf("<%02d,", col);
#endif
                        col = foldit(cp, col, foldwidth);
#ifdef DEBUG
                        if (debug)
                                printf("%02d>", col);
#endif
                }
                do {
                        putchar(*cp);
                } while (*++cp);
                c = rachar;
        }
        /*
         * terminate partial line with a hidden newline
         */
        if (fold && *(cp-1) != '\n')
                printf("\\\n");
}

__dead void
usage(void)
{
        extern char *__progname;

        fprintf(stderr, "usage: %s [-abcflnostw] [-F foldwidth] [file ...]\n",
            __progname);
        exit(1);
}