xref: /netbsd-src/usr.bin/locate/bigram/locate.bigram.c (revision 5f7096188587a2c7c95fa3c69b78e1ec9c7923d0)
1 /*
2  * Copyright (c) 1989 The Regents of the University of California.
3  * 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 char copyright[] =
39 "@(#) Copyright (c) 1989 The Regents of the University of California.\n\
40  All rights reserved.\n";
41 #endif /* not lint */
42 
43 #ifndef lint
44 /*static char sccsid[] = "from: @(#)locate.bigram.c	4.7 (Berkeley) 6/1/90";*/
45 static char rcsid[] = "$Id: locate.bigram.c,v 1.2 1993/08/01 18:13:55 mycroft Exp $";
46 #endif /* not lint */
47 
48 /*
49  *  bigram < text > bigrams
50  *
51  * List bigrams for 'updatedb' script.
52  * Use 'code' to encode a file using this output.
53  */
54 
55 #include <stdio.h>
56 #include <sys/param.h>			/* for MAXPATHLEN */
57 
58 char buf1[MAXPATHLEN] = " ";
59 char buf2[MAXPATHLEN];
60 
61 main ( )
62 {
63   	register char *cp;
64 	register char *oldpath = buf1, *path = buf2;
65 
66      	while ( fgets ( path, sizeof(buf2), stdin ) != NULL ) {
67 
68 		/* skip longest common prefix */
69 		for ( cp = path; *cp == *oldpath; cp++, oldpath++ )
70 			if ( *oldpath == NULL )
71 				break;
72 		/*
73 		 * output post-residue bigrams only
74 		 */
75 		while ( *cp != NULL && *(cp + 1) != NULL ) {
76 			putchar ( *cp++ );
77 			putchar ( *cp++ );
78 			putchar ( '\n' );
79 		}
80 		if ( path == buf1 )		/* swap pointers */
81 			path = buf2, oldpath = buf1;
82 		else
83 			path = buf1, oldpath = buf2;
84    	}
85 }
86