xref: /freebsd/usr.bin/cmp/special.c (revision 0b87f79976047c8f4332bbf7dc03146f6b0de79f)
1 /*-
2  * Copyright (c) 1991, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if 0
35 #ifndef lint
36 static char sccsid[] = "@(#)special.c	8.3 (Berkeley) 4/2/94";
37 #endif
38 #endif
39 
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42 
43 #include <sys/types.h>
44 
45 #include <err.h>
46 #include <stdlib.h>
47 #include <stdio.h>
48 #include <string.h>
49 
50 #include "extern.h"
51 
52 void
53 c_special(fd1, file1, skip1, fd2, file2, skip2)
54 	int fd1, fd2;
55 	const char *file1, *file2;
56 	off_t skip1, skip2;
57 {
58 	int ch1, ch2;
59 	off_t byte, line;
60 	FILE *fp1, *fp2;
61 	int dfound;
62 
63 	if ((fp1 = fdopen(fd1, "r")) == NULL)
64 		err(ERR_EXIT, "%s", file1);
65 	if ((fp2 = fdopen(fd2, "r")) == NULL)
66 		err(ERR_EXIT, "%s", file2);
67 
68 	dfound = 0;
69 	while (skip1--)
70 		if (getc(fp1) == EOF)
71 			goto eof;
72 	while (skip2--)
73 		if (getc(fp2) == EOF)
74 			goto eof;
75 
76 	for (byte = line = 1;; ++byte) {
77 		ch1 = getc(fp1);
78 		ch2 = getc(fp2);
79 		if (ch1 == EOF || ch2 == EOF)
80 			break;
81 		if (ch1 != ch2) {
82 			if (lflag) {
83 				dfound = 1;
84 				(void)printf("%6lld %3o %3o\n",
85 				    (long long)byte, ch1, ch2);
86 			} else {
87 				diffmsg(file1, file2, byte, line);
88 				/* NOTREACHED */
89 			}
90 		}
91 		if (ch1 == '\n')
92 			++line;
93 	}
94 
95 eof:	if (ferror(fp1))
96 		err(ERR_EXIT, "%s", file1);
97 	if (ferror(fp2))
98 		err(ERR_EXIT, "%s", file2);
99 	if (feof(fp1)) {
100 		if (!feof(fp2))
101 			eofmsg(file1);
102 	} else
103 		if (feof(fp2))
104 			eofmsg(file2);
105 	if (dfound)
106 		exit(DIFF_EXIT);
107 }
108