1/*
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.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * James A. Woods.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
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.
24 *
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
35 * SUCH DAMAGE.
36 *
|
37 * $FreeBSD: head/usr.bin/locate/code/locate.code.c 92920 2002-03-22 01:22:50Z imp $
|
| 37 * $FreeBSD: head/usr.bin/locate/code/locate.code.c 209571 2010-06-28 12:04:55Z gavin $ |
38 */
39
|
| 40#if 0 |
41#ifndef lint
42static char copyright[] =
43"@(#) Copyright (c) 1989, 1993\n\
44 The Regents of the University of California. All rights reserved.\n";
45#endif /* not lint */
46
47#ifndef lint
48static char sccsid[] = "@(#)locate.code.c 8.1 (Berkeley) 6/6/93";
49#endif /* not lint */
|
| 50#endif |
51
52/*
53 * PURPOSE: sorted list compressor (works with a modified 'find'
54 * to encode/decode a filename database)
55 *
56 * USAGE: bigram < list > bigrams
57 * process bigrams (see updatedb) > common_bigrams
58 * code common_bigrams < list > squozen_list
59 *
60 * METHOD: Uses 'front compression' (see ";login:", Volume 8, Number 1
61 * February/March 1983, p. 8). Output format is, per line, an
62 * offset differential count byte followed by a partially bigram-
63 * encoded ascii residue. A bigram is a two-character sequence,
64 * the first 128 most common of which are encoded in one byte.
65 *
66 * EXAMPLE: For simple front compression with no bigram encoding,
67 * if the input is... then the output is...
68 *
69 * /usr/src 0 /usr/src
70 * /usr/src/cmd/aardvark.c 8 /cmd/aardvark.c
71 * /usr/src/cmd/armadillo.c 14 armadillo.c
72 * /usr/tmp/zoo 5 tmp/zoo
73 *
74 * The codes are:
75 *
76 * 0-28 likeliest differential counts + offset to make nonnegative
77 * 30 switch code for out-of-range count to follow in next word
78 * 31 an 8 bit char followed
79 * 128-255 bigram codes (128 most common, as determined by 'updatedb')
80 * 32-127 single character (printable) ascii residue (ie, literal)
81 *
82 * The locate database store any character except newline ('\n')
83 * and NUL ('\0'). The 8-bit character support don't wast extra
84 * space until you have characters in file names less than 32
85 * or greather than 127.
86 *
87 *
88 * SEE ALSO: updatedb.sh, ../bigram/locate.bigram.c
89 *
90 * AUTHOR: James A. Woods, Informatics General Corp.,
91 * NASA Ames Research Center, 10/82
92 * 8-bit file names characters:
93 * Wolfram Schneider, Berlin September 1996
94 */
95
96#include <sys/param.h>
97#include <err.h>
98#include <errno.h>
99#include <stdlib.h>
100#include <string.h>
101#include <stdio.h>
102#include <unistd.h>
103#include "locate.h"
104
105#define BGBUFSIZE (NBG * 2) /* size of bigram buffer */
106
107u_char buf1[MAXPATHLEN] = " ";
108u_char buf2[MAXPATHLEN];
109u_char bigrams[BGBUFSIZE + 1] = { 0 };
110
111#define LOOKUP 1 /* use a lookup array instead a function, 3x faster */
112
113#ifdef LOOKUP
114#define BGINDEX(x) (big[(u_char)*x][(u_char)*(x + 1)])
115typedef short bg_t;
116bg_t big[UCHAR_MAX + 1][UCHAR_MAX + 1];
117#else
118#define BGINDEX(x) bgindex(x)
119typedef int bg_t;
120int bgindex(char *);
121#endif /* LOOKUP */
122
123
124void usage(void);
125
126int
|
125main(argc, argv)
126 int argc;
127 char *argv[];
|
| 127main(int argc, char *argv[]) |
128{
|
129 register u_char *cp, *oldpath, *path;
|
| 129 u_char *cp, *oldpath, *path; |
130 int ch, code, count, diffcount, oldcount;
|
| 131 u_int i, j; |
132 FILE *fp;
|
132 register int i, j;
|
133
134 while ((ch = getopt(argc, argv, "")) != -1)
135 switch(ch) {
136 default:
137 usage();
138 }
139 argc -= optind;
140 argv += optind;
141
142 if (argc != 1)
143 usage();
144
145 if ((fp = fopen(argv[0], "r")) == NULL)
146 err(1, "%s", argv[0]);
147
148 /* First copy bigram array to stdout. */
149 (void)fgets(bigrams, BGBUFSIZE + 1, fp);
150
151 if (fwrite(bigrams, 1, BGBUFSIZE, stdout) != BGBUFSIZE)
152 err(1, "stdout");
153 (void)fclose(fp);
154
155#ifdef LOOKUP
156 /* init lookup table */
157 for (i = 0; i < UCHAR_MAX + 1; i++)
158 for (j = 0; j < UCHAR_MAX + 1; j++)
159 big[i][j] = (bg_t)-1;
160
161 for (cp = bigrams, i = 0; *cp != '\0'; i += 2, cp += 2)
162 big[(u_char)*cp][(u_char)*(cp + 1)] = (bg_t)i;
163
164#endif /* LOOKUP */
165
166 oldpath = buf1;
167 path = buf2;
168 oldcount = 0;
169
170 while (fgets(path, sizeof(buf2), stdin) != NULL) {
171
172 /* skip empty lines */
173 if (*path == '\n')
174 continue;
175
176 /* remove newline */
177 for (cp = path; *cp != '\0'; cp++) {
178#ifndef LOCATE_CHAR30
179 /* old locate implementations core'd for char 30 */
180 if (*cp == SWITCH)
181 *cp = '?';
182 else
183#endif /* !LOCATE_CHAR30 */
184
185 /* chop newline */
186 if (*cp == '\n')
187 *cp = '\0';
188 }
189
190 /* Skip longest common prefix. */
191 for (cp = path; *cp == *oldpath; cp++, oldpath++)
192 if (*cp == '\0')
193 break;
194
195 count = cp - path;
196 diffcount = count - oldcount + OFFSET;
197 oldcount = count;
198 if (diffcount < 0 || diffcount > 2 * OFFSET) {
199 if (putchar(SWITCH) == EOF ||
200 putw(diffcount, stdout) == EOF)
201 err(1, "stdout");
202 } else
203 if (putchar(diffcount) == EOF)
204 err(1, "stdout");
205
206 while (*cp != '\0') {
207 /* print *two* characters */
208
209 if ((code = BGINDEX(cp)) != (bg_t)-1) {
210 /*
211 * print *one* as bigram
212 * Found, so mark byte with
213 * parity bit.
214 */
215 if (putchar((code / 2) | PARITY) == EOF)
216 err(1, "stdout");
217 cp += 2;
218 }
219
220 else {
221 for (i = 0; i < 2; i++) {
222 if (*cp == '\0')
223 break;
224
225 /* print umlauts in file names */
226 if (*cp < ASCII_MIN ||
227 *cp > ASCII_MAX) {
228 if (putchar(UMLAUT) == EOF ||
229 putchar(*cp++) == EOF)
230 err(1, "stdout");
231 }
232
233 else {
234 /* normal character */
235 if(putchar(*cp++) == EOF)
236 err(1, "stdout");
237 }
238 }
239
240 }
241 }
242
243 if (path == buf1) { /* swap pointers */
244 path = buf2;
245 oldpath = buf1;
246 } else {
247 path = buf1;
248 oldpath = buf2;
249 }
250 }
251 /* Non-zero status if there were errors */
252 if (fflush(stdout) != 0 || ferror(stdout))
253 exit(1);
254 exit(0);
255}
256
257#ifndef LOOKUP
258int
|
259bgindex(bg) /* Return location of bg in bigrams or -1. */
260 char *bg;
|
| 259bgindex(char *bg) /* Return location of bg in bigrams or -1. */ |
260{
|
262 register char bg0, bg1, *p;
|
| 261 char bg0, bg1, *p; |
262
263 bg0 = bg[0];
264 bg1 = bg[1];
265 for (p = bigrams; *p != NULL; p++)
266 if (*p++ == bg0 && *p == bg1)
267 break;
268 return (*p == NULL ? -1 : (--p - bigrams));
269}
270#endif /* !LOOKUP */
271
272void
|
274usage()
|
| 273usage(void) |
274{
275 (void)fprintf(stderr,
276 "usage: locate.code common_bigrams < list > squozen_list\n");
277 exit(1);
278}
|