2 * Copyright (c) 1995 Wolfram Schneider <wosch@FreeBSD.org>. Berlin.
3 * Copyright (c) 1989, 1993
4 * The Regents of the University of California. All rights reserved.
6 * This code is derived from software contributed to Berkeley by
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed by the University of
20 * California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * $FreeBSD: src/usr.bin/locate/code/locate.code.c,v 1.11.2.1 2001/03/04 08:46:46 kris Exp $
38 * $DragonFly: src/usr.bin/locate/code/locate.code.c,v 1.4 2005/08/04 17:31:23 drhodus Exp $
40 * @(#) Copyright (c) 1989, 1993 The Regents of the University of California. All rights reserved.
41 * @(#)locate.code.c 8.1 (Berkeley) 6/6/93
45 * PURPOSE: sorted list compressor (works with a modified 'find'
46 * to encode/decode a filename database)
48 * USAGE: bigram < list > bigrams
49 * process bigrams (see updatedb) > common_bigrams
50 * code common_bigrams < list > squozen_list
52 * METHOD: Uses 'front compression' (see ";login:", Volume 8, Number 1
53 * February/March 1983, p. 8). Output format is, per line, an
54 * offset differential count byte followed by a partially bigram-
55 * encoded ascii residue. A bigram is a two-character sequence,
56 * the first 128 most common of which are encoded in one byte.
58 * EXAMPLE: For simple front compression with no bigram encoding,
59 * if the input is... then the output is...
62 * /usr/src/cmd/aardvark.c 8 /cmd/aardvark.c
63 * /usr/src/cmd/armadillo.c 14 armadillo.c
64 * /usr/tmp/zoo 5 tmp/zoo
68 * 0-28 likeliest differential counts + offset to make nonnegative
69 * 30 switch code for out-of-range count to follow in next word
70 * 31 an 8 bit char followed
71 * 128-255 bigram codes (128 most common, as determined by 'updatedb')
72 * 32-127 single character (printable) ascii residue (ie, literal)
74 * The locate database store any character except newline ('\n')
75 * and NUL ('\0'). The 8-bit character support don't wast extra
76 * space until you have characters in file names less than 32
77 * or greather than 127.
80 * SEE ALSO: updatedb.sh, ../bigram/locate.bigram.c
82 * AUTHOR: James A. Woods, Informatics General Corp.,
83 * NASA Ames Research Center, 10/82
84 * 8-bit file names characters:
85 * Wolfram Schneider, Berlin September 1996
88 #include <sys/param.h>
97 #define BGBUFSIZE (NBG * 2) /* size of bigram buffer */
99 u_char buf1
[MAXPATHLEN
] = " ";
100 u_char buf2
[MAXPATHLEN
];
101 u_char bigrams
[BGBUFSIZE
+ 1] = { 0 };
103 #define LOOKUP 1 /* use a lookup array instead a function, 3x faster */
106 #define BGINDEX(x) (big[(u_char)*x][(u_char)*(x + 1)])
108 bg_t big
[UCHAR_MAX
+ 1][UCHAR_MAX
+ 1];
110 #define BGINDEX(x) bgindex(x)
123 u_char
*cp
, *oldpath
, *path
;
124 int ch
, code
, count
, diffcount
, oldcount
;
128 while ((ch
= getopt(argc
, argv
, "")) != -1)
139 if ((fp
= fopen(argv
[0], "r")) == NULL
)
140 err(1, "%s", argv
[0]);
142 /* First copy bigram array to stdout. */
143 (void)fgets(bigrams
, BGBUFSIZE
+ 1, fp
);
145 if (fwrite(bigrams
, 1, BGBUFSIZE
, stdout
) != BGBUFSIZE
)
150 /* init lookup table */
151 for (i
= 0; i
< UCHAR_MAX
+ 1; i
++)
152 for (j
= 0; j
< UCHAR_MAX
+ 1; j
++)
153 big
[i
][j
] = (bg_t
)-1;
155 for (cp
= bigrams
, i
= 0; *cp
!= '\0'; i
+= 2, cp
+= 2)
156 big
[(u_char
)*cp
][(u_char
)*(cp
+ 1)] = (bg_t
)i
;
164 while (fgets(path
, sizeof(buf2
), stdin
) != NULL
) {
166 /* skip empty lines */
171 for (cp
= path
; *cp
!= '\0'; cp
++) {
172 #ifndef LOCATE_CHAR30
173 /* old locate implementations core'd for char 30 */
177 #endif /* !LOCATE_CHAR30 */
184 /* Skip longest common prefix. */
185 for (cp
= path
; *cp
== *oldpath
; cp
++, oldpath
++)
190 diffcount
= count
- oldcount
+ OFFSET
;
192 if (diffcount
< 0 || diffcount
> 2 * OFFSET
) {
193 if (putchar(SWITCH
) == EOF
||
194 putw(diffcount
, stdout
) == EOF
)
197 if (putchar(diffcount
) == EOF
)
200 while (*cp
!= '\0') {
201 /* print *two* characters */
203 if ((code
= BGINDEX(cp
)) != (bg_t
)-1) {
205 * print *one* as bigram
206 * Found, so mark byte with
209 if (putchar((code
/ 2) | PARITY
) == EOF
)
215 for (i
= 0; i
< 2; i
++) {
219 /* print umlauts in file names */
220 if (*cp
< ASCII_MIN
||
222 if (putchar(UMLAUT
) == EOF
||
223 putchar(*cp
++) == EOF
)
228 /* normal character */
229 if(putchar(*cp
++) == EOF
)
237 if (path
== buf1
) { /* swap pointers */
245 /* Non-zero status if there were errors */
246 if (fflush(stdout
) != 0 || ferror(stdout
))
253 bgindex(bg
) /* Return location of bg in bigrams or -1. */
260 for (p
= bigrams
; *p
!= NULL
; p
++)
261 if (*p
++ == bg0
&& *p
== bg1
)
263 return (*p
== NULL
? -1 : (--p
- bigrams
));
270 (void)fprintf(stderr
,
271 "usage: locate.code common_bigrams < list > squozen_list\n");