xref: /dragonfly/usr.bin/cmp/special.c (revision 6e278935)
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  * $FreeBSD: src/usr.bin/cmp/special.c,v 1.4.2.1 2001/11/21 10:47:54 dwmalone Exp $
34  * $DragonFly: src/usr.bin/cmp/special.c,v 1.3 2003/10/02 17:42:27 hmp Exp $
35  *
36  * @(#)special.c	8.3 (Berkeley) 4/2/94
37  */
38 
39 #include <sys/types.h>
40 
41 #include <err.h>
42 #include <stdlib.h>
43 #include <stdio.h>
44 #include <string.h>
45 
46 #include "extern.h"
47 
48 void
49 c_special(int fd1, const char *file1, off_t skip1, int fd2, const char *file2,
50           off_t skip2)
51 {
52 	int ch1, ch2;
53 	off_t byte, line;
54 	FILE *fp1, *fp2;
55 	int dfound;
56 
57 	if ((fp1 = fdopen(fd1, "r")) == NULL)
58 		err(ERR_EXIT, "%s", file1);
59 	if ((fp2 = fdopen(fd2, "r")) == NULL)
60 		err(ERR_EXIT, "%s", file2);
61 
62 	dfound = 0;
63 	while (skip1--)
64 		if (getc(fp1) == EOF)
65 			goto eof;
66 	while (skip2--)
67 		if (getc(fp2) == EOF)
68 			goto eof;
69 
70 	for (byte = line = 1;; ++byte) {
71 		ch1 = getc(fp1);
72 		ch2 = getc(fp2);
73 		if (ch1 == EOF || ch2 == EOF)
74 			break;
75 		if (ch1 != ch2) {
76 			if (xflag) {
77 				dfound = 1;
78 				printf("%08jx %02x %02x\n",
79 				       (intmax_t)byte - 1, ch1, ch2);
80 			} else if (lflag) {
81 				dfound = 1;
82 				printf("%6jd %3o %3o\n",
83 				       (intmax_t)byte, ch1, ch2);
84 			} else {
85 				diffmsg(file1, file2, byte, line);
86 				/* NOTREACHED */
87 			}
88 		}
89 		if (ch1 == '\n')
90 			++line;
91 	}
92 
93 eof:	if (ferror(fp1))
94 		err(ERR_EXIT, "%s", file1);
95 	if (ferror(fp2))
96 		err(ERR_EXIT, "%s", file2);
97 	if (feof(fp1)) {
98 		if (!feof(fp2))
99 			eofmsg(file1);
100 	} else
101 		if (feof(fp2))
102 			eofmsg(file2);
103 	if (dfound)
104 		exit(DIFF_EXIT);
105 }
106