xref: /freebsd/usr.bin/locate/bigram/locate.bigram.c (revision f39bffc62c1395bde25d152c7f68fdf7cbaab414)
1 /*
2  * SPDX-License-Identifier: BSD-4-Clause
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. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  *
39  * $FreeBSD$
40  */
41 
42 #if 0
43 #ifndef lint
44 static char copyright[] =
45 "@(#) Copyright (c) 1989, 1993\n\
46 	The Regents of the University of California.  All rights reserved.\n";
47 #endif /* not lint */
48 
49 #ifndef lint
50 static char sccsid[] = "@(#)locate.bigram.c	8.1 (Berkeley) 6/6/93";
51 #endif /* not lint */
52 #endif
53 
54 /*
55  *  bigram < sorted_file_names | sort -nr |
56  *  	awk 'NR <= 128 { printf $2 }' > bigrams
57  *
58  * List bigrams for 'updatedb' script.
59  * Use 'code' to encode a file using this output.
60  */
61 
62 #include <capsicum_helpers.h>
63 #include <err.h>
64 #include <errno.h>
65 #include <stdio.h>
66 #include <stdlib.h>
67 #include <sys/param.h>			/* for MAXPATHLEN */
68 #include "locate.h"
69 
70 u_char buf1[MAXPATHLEN] = " ";
71 u_char buf2[MAXPATHLEN];
72 u_int bigram[UCHAR_MAX + 1][UCHAR_MAX + 1];
73 
74 int
75 main(void)
76 {
77 	u_char *cp;
78 	u_char *oldpath = buf1, *path = buf2;
79 	u_int i, j;
80 
81 	if (caph_limit_stdio() < 0 || (cap_enter() < 0 && errno != ENOSYS))
82 		err(1, "capsicum");
83 
84      	while (fgets(path, sizeof(buf2), stdin) != NULL) {
85 
86 		/*
87 		 * We don't need remove newline character '\n'.
88 		 * '\n' is less than ASCII_MIN and will be later
89 		 * ignored at output.
90 		 */
91 
92 
93 		/* skip longest common prefix */
94 		for (cp = path; *cp == *oldpath; cp++, oldpath++)
95 			if (*cp == '\0')
96 				break;
97 
98 		while (*cp != '\0' && *(cp + 1) != '\0') {
99 			bigram[(u_char)*cp][(u_char)*(cp + 1)]++;
100 			cp += 2;
101 		}
102 
103 		/* swap pointers */
104 		if (path == buf1) {
105 			path = buf2;
106 			oldpath = buf1;
107 		} else {
108 			path = buf1;
109 			oldpath = buf2;
110 		}
111    	}
112 
113 	/* output, boundary check */
114 	for (i = ASCII_MIN; i <= ASCII_MAX; i++)
115 		for (j = ASCII_MIN; j <= ASCII_MAX; j++)
116 			if (bigram[i][j] != 0)
117 				(void)printf("%4u %c%c\n", bigram[i][j], i, j);
118 
119 	exit(0);
120 }
121