xref: /freebsd/usr.bin/locate/bigram/locate.bigram.c (revision c44252b6e8da46f58fd1882b9e7305a0f9114c16)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * James A. Woods.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 static char copyright[] =
39 "@(#) Copyright (c) 1989, 1993\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif /* not lint */
42 
43 #ifndef lint
44 static char sccsid[] = "@(#)locate.bigram.c	8.2 (Berkeley) 4/28/95";
45 #endif /* not lint */
46 
47 /*
48  *  bigram < text > bigrams
49  *
50  * List bigrams for 'updatedb' script.
51  * Use 'code' to encode a file using this output.
52  */
53 
54 #include <stdio.h>
55 #include <sys/param.h>			/* for MAXPATHLEN */
56 
57 char buf1[MAXPATHLEN] = " ";
58 char buf2[MAXPATHLEN];
59 
60 main ( )
61 {
62   	register char *cp;
63 	register char *oldpath = buf1, *path = buf2;
64 
65      	while ( fgets ( path, sizeof(buf2), stdin ) != NULL ) {
66 
67 		/* skip longest common prefix */
68 		for ( cp = path; *cp == *oldpath; cp++, oldpath++ )
69 			if ( *oldpath == '\0' )
70 				break;
71 		/*
72 		 * output post-residue bigrams only
73 		 */
74 		while ( *cp != '\0' && *(cp + 1) != '\0' ) {
75 			putchar ( *cp++ );
76 			putchar ( *cp++ );
77 			putchar ( '\n' );
78 		}
79 		if ( path == buf1 )		/* swap pointers */
80 			path = buf2, oldpath = buf1;
81 		else
82 			path = buf1, oldpath = buf2;
83    	}
84 	return (0);
85 }
86