xref: /openbsd/usr.bin/cmp/special.c (revision a6445c1d)
1 /*      $OpenBSD: special.c,v 1.7 2011/01/19 13:01:25 okan Exp $      */
2 /*      $NetBSD: special.c,v 1.2 1995/09/08 03:23:00 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. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/types.h>
34 
35 #include <err.h>
36 #include <stdlib.h>
37 #include <stdio.h>
38 #include <string.h>
39 
40 #include "extern.h"
41 
42 void
43 c_special(int fd1, char *file1, off_t skip1, int fd2, char *file2, off_t skip2)
44 {
45 	int ch1, ch2;
46 	off_t byte, line;
47 	FILE *fp1, *fp2;
48 	int dfound;
49 
50 	if ((fp1 = fdopen(fd1, "r")) == NULL)
51 		err(ERR_EXIT, "%s", file1);
52 	if ((fp2 = fdopen(fd2, "r")) == NULL)
53 		err(ERR_EXIT, "%s", file2);
54 
55 	dfound = 0;
56 	while (skip1--)
57 		if (getc(fp1) == EOF)
58 			goto eof;
59 	while (skip2--)
60 		if (getc(fp2) == EOF)
61 			goto eof;
62 
63 	for (byte = line = 1;; ++byte) {
64 		ch1 = getc(fp1);
65 		ch2 = getc(fp2);
66 		if (ch1 == EOF || ch2 == EOF)
67 			break;
68 		if (ch1 != ch2) {
69 			if (lflag) {
70 				dfound = 1;
71 				(void)printf("%6lld %3o %3o\n", (long long)byte,
72 				    ch1, ch2);
73 			} else
74 				diffmsg(file1, file2, byte, line);
75 				/* NOTREACHED */
76 		}
77 		if (ch1 == '\n')
78 			++line;
79 	}
80 
81 eof:	if (ferror(fp1))
82 		err(ERR_EXIT, "%s", file1);
83 	if (ferror(fp2))
84 		err(ERR_EXIT, "%s", file2);
85 	if (feof(fp1)) {
86 		if (!feof(fp2))
87 			eofmsg(file1);
88 	} else
89 		if (feof(fp2))
90 			eofmsg(file2);
91 	if (dfound)
92 		exit(DIFF_EXIT);
93 }
94