1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2005 Brian Somers <[email protected]>
5 * 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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 #include <sys/types.h>
31
32 #include <err.h>
33 #include <limits.h>
34 #include <stdbool.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <unistd.h>
38
39 #include "extern.h"
40
41 int
c_link(const char * file1,off_t skip1,const char * file2,off_t skip2,off_t limit)42 c_link(const char *file1, off_t skip1, const char *file2, off_t skip2,
43 off_t limit)
44 {
45 char buf1[PATH_MAX], *p1;
46 char buf2[PATH_MAX], *p2;
47 ssize_t len1, len2;
48 int dfound;
49 off_t byte;
50 u_char ch;
51
52 if ((len1 = readlink(file1, buf1, sizeof(buf1) - 1)) < 0) {
53 if (!sflag)
54 err(ERR_EXIT, "%s", file1);
55 else
56 exit(ERR_EXIT);
57 }
58
59 if ((len2 = readlink(file2, buf2, sizeof(buf2) - 1)) < 0) {
60 if (!sflag)
61 err(ERR_EXIT, "%s", file2);
62 else
63 exit(ERR_EXIT);
64 }
65
66 if (skip1 > len1)
67 skip1 = len1;
68 buf1[len1] = '\0';
69
70 if (skip2 > len2)
71 skip2 = len2;
72 buf2[len2] = '\0';
73
74 dfound = 0;
75 byte = 1;
76 for (p1 = buf1 + skip1, p2 = buf2 + skip2;
77 *p1 && *p2 && (limit == 0 || byte <= limit); p1++, p2++) {
78 if ((ch = *p1) != *p2) {
79 if (xflag) {
80 dfound = 1;
81 (void)printf("%08llx %02x %02x\n",
82 (long long)byte - 1, ch, *p2);
83 } else if (lflag) {
84 dfound = 1;
85 if (bflag)
86 (void)printf("%6lld %3o %c %3o %c\n",
87 (long long)byte, ch, ch, *p2, *p2);
88 else
89 (void)printf("%6lld %3o %3o\n",
90 (long long)byte, ch, *p2);
91 } else {
92 diffmsg(file1, file2, byte, 1, ch, *p2);
93 return (DIFF_EXIT);
94 }
95 }
96 byte++;
97 }
98
99 if (*p1 || *p2) {
100 eofmsg (*p1 ? file2 : file1);
101 return (DIFF_EXIT);
102 }
103 return (dfound ? DIFF_EXIT : 0);
104 }
105