1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1991, 1993, 1994
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#if 0
33#ifndef lint
34static char sccsid[] = "@(#)special.c	8.3 (Berkeley) 4/2/94";
35#endif
36#endif
37
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD$");
40
41#include <sys/types.h>
42
43#include <capsicum_helpers.h>
44#include <err.h>
45#include <stdlib.h>
46#include <stdio.h>
47
48#include "extern.h"
49
50void
51c_special(int fd1, const char *file1, off_t skip1,
52    int fd2, const char *file2, off_t skip2)
53{
54	int ch1, ch2;
55	off_t byte, line;
56	FILE *fp1, *fp2;
57	int dfound;
58
59	if (caph_limit_stream(fd1, CAPH_READ) < 0)
60		err(ERR_EXIT, "caph_limit_stream(%s)", file1);
61	if (caph_limit_stream(fd2, CAPH_READ) < 0)
62		err(ERR_EXIT, "caph_limit_stream(%s)", file2);
63	if (caph_enter() < 0)
64		err(ERR_EXIT, "unable to enter capability mode");
65
66	if ((fp1 = fdopen(fd1, "r")) == NULL)
67		err(ERR_EXIT, "%s", file1);
68	if ((fp2 = fdopen(fd2, "r")) == NULL)
69		err(ERR_EXIT, "%s", file2);
70
71	dfound = 0;
72	while (skip1--)
73		if (getc(fp1) == EOF)
74			goto eof;
75	while (skip2--)
76		if (getc(fp2) == EOF)
77			goto eof;
78
79	for (byte = line = 1;; ++byte) {
80		ch1 = getc(fp1);
81		ch2 = getc(fp2);
82		if (ch1 == EOF || ch2 == EOF)
83			break;
84		if (ch1 != ch2) {
85			if (xflag) {
86				dfound = 1;
87				(void)printf("%08llx %02x %02x\n",
88				    (long long)byte - 1, ch1, ch2);
89			} else if (lflag) {
90				dfound = 1;
91				(void)printf("%6lld %3o %3o\n",
92				    (long long)byte, ch1, ch2);
93			} else {
94				diffmsg(file1, file2, byte, line);
95				/* NOTREACHED */
96			}
97		}
98		if (ch1 == '\n')
99			++line;
100	}
101
102eof:	if (ferror(fp1))
103		err(ERR_EXIT, "%s", file1);
104	if (ferror(fp2))
105		err(ERR_EXIT, "%s", file2);
106	if (feof(fp1)) {
107		if (!feof(fp2))
108			eofmsg(file1);
109	} else
110		if (feof(fp2))
111			eofmsg(file2);
112	fclose(fp2);
113	fclose(fp1);
114	if (dfound)
115		exit(DIFF_EXIT);
116}
117