regular.c revision 1.9 
1/*	$NetBSD: regular.c,v 1.9 2000/07/18 10:23:43 jdolecek Exp $	*/
2
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. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#include <sys/cdefs.h>
37#ifndef lint
38#if 0
39static char sccsid[] = "@(#)regular.c	8.3 (Berkeley) 4/2/94";
40#else
41__RCSID("$NetBSD: regular.c,v 1.9 2000/07/18 10:23:43 jdolecek Exp $");
42#endif
43#endif /* not lint */
44
45#include <sys/param.h>
46#include <sys/mman.h>
47#include <sys/stat.h>
48
49#include <err.h>
50#include <limits.h>
51#include <stdlib.h>
52#include <stdio.h>
53#include <string.h>
54
55#include "extern.h"
56
57void
58c_regular(fd1, file1, skip1, len1, fd2, file2, skip2, len2)
59	int fd1, fd2;
60	char *file1, *file2;
61	off_t skip1, len1, skip2, len2;
62{
63	u_char ch, *p1, *p2;
64	off_t byte, length, line;
65	int dfound;
66
67	if (sflag && len1 != len2)
68		exit(1);
69
70	if (skip1 > len1)
71		eofmsg(file1);
72	len1 -= skip1;
73	if (skip2 > len2)
74		eofmsg(file2);
75	len2 -= skip2;
76
77	length = MIN(len1, len2);
78	if (length > SIZE_T_MAX) {
79mmap_failed:
80		c_special(fd1, file1, skip1, fd2, file2, skip2);
81		return;
82	}
83
84	if ((p1 = (u_char *)mmap(NULL, (size_t)length,
85	    PROT_READ, MAP_FILE, fd1, skip1)) == MAP_FAILED)
86		goto mmap_failed;
87	(void)madvise(p1, (size_t)length, MADV_SEQUENTIAL);
88
89	if ((p2 = (u_char *)mmap(NULL, (size_t)length,
90	    PROT_READ, MAP_FILE, fd2, skip2)) == MAP_FAILED) {
91		munmap(p1, (size_t) length);
92		goto mmap_failed;
93	}
94	(void)madvise(p2, (size_t)length, MADV_SEQUENTIAL);
95
96	dfound = 0;
97	for (byte = line = 1; length--; ++p1, ++p2, ++byte) {
98		if ((ch = *p1) != *p2) {
99			if (lflag) {
100				dfound = 1;
101				(void)printf("%6qd %3o %3o\n", (long long)byte,
102				    ch, *p2);
103			} else
104				diffmsg(file1, file2, byte, line);
105				/* NOTREACHED */
106		}
107		if (ch == '\n')
108			++line;
109	}
110
111	if (len1 != len2)
112		eofmsg (len1 > len2 ? file2 : file1);
113	if (dfound)
114		exit(DIFF_EXIT);
115}
116