1 /*
2 * $OpenBSD: locate.bigram.c,v 1.16 2019/01/17 06:15:44 tedu Exp $
3 *
4 * Copyright (c) 1995 Wolfram Schneider <wosch@FreeBSD.org>. Berlin.
5 * Copyright (c) 1989, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * James A. Woods.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 /*
37 * bigram < sorted_file_names | sort -nr |
38 * awk 'NR <= 128 { printf $2 }' > bigrams
39 *
40 * List bigrams for 'updatedb' script.
41 * Use 'code' to encode a file using this output.
42 */
43
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <limits.h>
47 #include <unistd.h>
48 #include <err.h>
49 #include "locate.h"
50
51 u_char buf1[PATH_MAX] = " ";
52 u_char buf2[PATH_MAX];
53 u_int bigram[UCHAR_MAX + 1][UCHAR_MAX + 1];
54
55 int
main(void)56 main(void)
57 {
58 u_char *cp;
59 u_char *oldpath = buf1, *path = buf2;
60 u_int i, j;
61
62 if (pledge("stdio", NULL) == -1)
63 err(1, "pledge");
64
65 while (fgets(path, sizeof(buf2), stdin) != NULL) {
66
67 /*
68 * We don't need remove newline character '\n'.
69 * '\n' is less than ASCII_MIN and will be later
70 * ignored at output.
71 */
72
73
74 /* skip longest common prefix */
75 for (cp = path; *cp == *oldpath; cp++, oldpath++)
76 if (*cp == '\0')
77 break;
78
79 while (*cp != '\0' && *(cp + 1) != '\0') {
80 bigram[(u_char)*cp][(u_char)*(cp + 1)]++;
81 cp += 2;
82 }
83
84 /* swap pointers */
85 if (path == buf1) {
86 path = buf2;
87 oldpath = buf1;
88 } else {
89 path = buf1;
90 oldpath = buf2;
91 }
92 }
93
94 /* output, boundary check */
95 for (i = ASCII_MIN; i <= ASCII_MAX; i++)
96 for (j = ASCII_MIN; j <= ASCII_MAX; j++)
97 if (bigram[i][j] != 0)
98 (void)printf("%4u\t%c%c\n", bigram[i][j], i, j);
99
100 exit(0);
101 }
102