xref: /netbsd-src/usr.bin/cmp/special.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: special.c,v 1.13 2009/04/11 12:16:12 lukem 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. 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 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)special.c	8.3 (Berkeley) 4/2/94";
36 #else
37 __RCSID("$NetBSD: special.c,v 1.13 2009/04/11 12:16:12 lukem Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include <sys/types.h>
42 
43 #include <err.h>
44 #include <stdlib.h>
45 #include <stdio.h>
46 #include <string.h>
47 
48 #include "extern.h"
49 
50 void
51 c_special(int fd1, const char *file1, off_t skip1, int fd2, const char *file2, off_t skip2)
52 {
53 	int ch1, ch2;
54 	off_t byte, line;
55 	FILE *fp1, *fp2;
56 	int dfound;
57 
58 	dfound = 0;
59 	if ((fp1 = fdopen(fd1, "r")) == NULL)
60 		err(ERR_EXIT, "%s", file1);
61 	if ((fp2 = fdopen(fd2, "r")) == NULL)
62 		err(ERR_EXIT, "%s", file2);
63 
64 	for (byte = line = 1; skip1--; byte++) {
65 		ch1 = getc(fp1);
66 		if (ch1 == EOF)
67 			goto eof;
68 		if (ch1 == '\n')
69 			line++;
70 	}
71 	for (byte = line = 1; skip2--; byte++) {
72 		ch2 = getc(fp2);
73 		if (ch2 == EOF)
74 			goto eof;
75 		if (ch2 == '\n')
76 			line++;
77 	}
78 	dfound = 0;
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 (lflag) {
86 				dfound = 1;
87 				(void)printf("%6lld %3o %3o\n", (long long)byte,
88 				    ch1, ch2);
89 			} else
90 				diffmsg(file1, file2, byte, line);
91 				/* NOTREACHED */
92 		}
93 		if (ch1 == '\n')
94 			++line;
95 	}
96 
97  eof:
98 	if (ferror(fp1))
99 		errmsg(file1, byte, line);
100 	if (ferror(fp2))
101 		errmsg(file2, byte, line);
102 	if (feof(fp1)) {
103 		if (!feof(fp2))
104 			eofmsg(file1, byte, line);
105 	} else
106 		if (feof(fp2))
107 			eofmsg(file2, byte, line);
108 	(void)fclose(fp1);
109 	(void)fclose(fp2);
110 	if (dfound)
111 		exit(DIFF_EXIT);
112 }
113