xref: /openbsd-src/usr.bin/cmp/regular.c (revision ad9ccaa89e3b2c41dcd176d05cfbb88e22cd7c90)
1 /*      $OpenBSD: regular.c,v 1.4 2000/10/12 10:03:20 kevlo Exp $      */
2 /*      $NetBSD: regular.c,v 1.2 1995/09/08 03:22:59 tls Exp $      */
3 
4 /*-
5  * Copyright (c) 1991, 1993, 1994
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)regular.c	8.3 (Berkeley) 4/2/94";
40 #else
41 static char rcsid[] = "$OpenBSD: regular.c,v 1.4 2000/10/12 10:03:20 kevlo 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 
57 void
58 c_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) {
79 	mmap_failed:
80 		c_special(fd1, file1, skip1, fd2, file2, skip2);
81 		return;
82 	}
83 
84 	if ((p1 = mmap(NULL, (size_t)length, PROT_READ,
85 		       MAP_PRIVATE, fd1, skip1)) == MAP_FAILED)
86 		goto mmap failed;
87 	if ((p2 = mmap(NULL, (size_t)length, PROT_READ,
88 		       MAP_PRIVATE, fd2, skip2)) == MAP_FAILED) {
89 		munmap(p1, (size_t)length);
90 		goto mmap_failed;
91 	}
92 
93 	dfound = 0;
94 	for (byte = line = 1; length--; ++p1, ++p2, ++byte) {
95 		if ((ch = *p1) != *p2) {
96 			if (lflag) {
97 				dfound = 1;
98 				(void)printf("%6qd %3o %3o\n", byte, ch, *p2);
99 			} else
100 				diffmsg(file1, file2, byte, line);
101 				/* NOTREACHED */
102 		}
103 		if (ch == '\n')
104 			++line;
105 	}
106 
107 	if (len1 != len2)
108 		eofmsg (len1 > len2 ? file2 : file1);
109 	if (dfound)
110 		exit(DIFF_EXIT);
111 }
112