xref: /freebsd/usr.bin/locate/locate/locate.c (revision 780fb4a2)
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 
40 #ifndef lint
41 static const char copyright[] =
42 "@(#) Copyright (c) 1995-1996 Wolfram Schneider, Berlin.\n\
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
48 #if 0
49 static char sccsid[] = "@(#)locate.c    8.1 (Berkeley) 6/6/93";
50 #endif
51 static const char rcsid[] =
52   "$FreeBSD$";
53 #endif /* not lint */
54 
55 /*
56  * Ref: Usenix ;login:, Vol 8, No 1, February/March, 1983, p. 8.
57  *
58  * Locate scans a file list for the full pathname of a file given only part
59  * of the name.  The list has been processed with with "front-compression"
60  * and bigram coding.  Front compression reduces space by a factor of 4-5,
61  * bigram coding by a further 20-25%.
62  *
63  * The codes are:
64  *
65  *      0-28    likeliest differential counts + offset to make nonnegative
66  *      30      switch code for out-of-range count to follow in next word
67  *      31      an 8 bit char followed
68  *      128-255 bigram codes (128 most common, as determined by 'updatedb')
69  *      32-127  single character (printable) ascii residue (ie, literal)
70  *
71  * A novel two-tiered string search technique is employed:
72  *
73  * First, a metacharacter-free subpattern and partial pathname is matched
74  * BACKWARDS to avoid full expansion of the pathname list.  The time savings
75  * is 40-50% over forward matching, which cannot efficiently handle
76  * overlapped search patterns and compressed path residue.
77  *
78  * Then, the actual shell glob-style regular expression (if in this form) is
79  * matched against the candidate pathnames using the slower routines provided
80  * in the standard 'find'.
81  */
82 
83 #include <sys/param.h>
84 #include <ctype.h>
85 #include <err.h>
86 #include <fnmatch.h>
87 #include <locale.h>
88 #include <stdio.h>
89 #include <stdlib.h>
90 #include <string.h>
91 #include <unistd.h>
92 
93 #ifdef MMAP
94 #  include <sys/types.h>
95 #  include <sys/stat.h>
96 #  include <sys/mman.h>
97 #  include <fcntl.h>
98 #endif
99 
100 
101 #include "locate.h"
102 #include "pathnames.h"
103 
104 #ifdef DEBUG
105 #  include <sys/time.h>
106 #  include <sys/types.h>
107 #  include <sys/resource.h>
108 #endif
109 
110 int f_mmap;             /* use mmap */
111 int f_icase;            /* ignore case */
112 int f_stdin;            /* read database from stdin */
113 int f_statistic;        /* print statistic */
114 int f_silent;           /* suppress output, show only count of matches */
115 int f_limit;            /* limit number of output lines, 0 == infinite */
116 u_int counter;          /* counter for matches [-c] */
117 char separator='\n';	/* line separator */
118 
119 
120 void    usage(void);
121 void    statistic(FILE *, char *);
122 void    fastfind(FILE *, char *, char *);
123 void    fastfind_icase(FILE *, char *, char *);
124 void    fastfind_mmap(char *, caddr_t, int, char *);
125 void    fastfind_mmap_icase(char *, caddr_t, int, char *);
126 void	search_mmap(char *, char **);
127 void	search_fopen(char *, char **);
128 unsigned long cputime(void);
129 
130 extern char     **colon(char **, char*, char*);
131 extern void     print_matches(u_int);
132 extern int      getwm(caddr_t);
133 extern int      getwf(FILE *);
134 extern u_char   *tolower_word(u_char *);
135 extern int	check_bigram_char(int);
136 extern char 	*patprep(char *);
137 
138 int
139 main(int argc, char **argv)
140 {
141         register int ch;
142         char **dbv = NULL;
143 	char *path_fcodes;      /* locate database */
144 #ifdef MMAP
145         f_mmap = 1;		/* mmap is default */
146 #endif
147 	(void) setlocale(LC_ALL, "");
148 
149         while ((ch = getopt(argc, argv, "0Scd:il:ms")) != -1)
150                 switch(ch) {
151                 case '0':	/* 'find -print0' style */
152 			separator = '\0';
153 			break;
154                 case 'S':	/* statistic lines */
155                         f_statistic = 1;
156                         break;
157                 case 'l': /* limit number of output lines, 0 == infinite */
158                         f_limit = atoi(optarg);
159                         break;
160                 case 'd':	/* database */
161                         dbv = colon(dbv, optarg, _PATH_FCODES);
162                         break;
163                 case 'i':	/* ignore case */
164                         f_icase = 1;
165                         break;
166                 case 'm':	/* mmap */
167 #ifdef MMAP
168                         f_mmap = 1;
169 #else
170 						warnx("mmap(2) not implemented");
171 #endif
172                         break;
173                 case 's':	/* stdio lib */
174                         f_mmap = 0;
175                         break;
176                 case 'c': /* suppress output, show only count of matches */
177                         f_silent = 1;
178                         break;
179                 default:
180                         usage();
181                 }
182         argv += optind;
183         argc -= optind;
184 
185         /* to few arguments */
186         if (argc < 1 && !(f_statistic))
187                 usage();
188 
189         /* no (valid) database as argument */
190         if (dbv == NULL || *dbv == NULL) {
191                 /* try to read database from environment */
192                 if ((path_fcodes = getenv("LOCATE_PATH")) == NULL ||
193 		     *path_fcodes == '\0')
194                         /* use default database */
195                         dbv = colon(dbv, _PATH_FCODES, _PATH_FCODES);
196                 else		/* $LOCATE_PATH */
197                         dbv = colon(dbv, path_fcodes, _PATH_FCODES);
198         }
199 
200         if (f_icase && UCHAR_MAX < 4096) /* init tolower lookup table */
201                 for (ch = 0; ch < UCHAR_MAX + 1; ch++)
202                         myctype[ch] = tolower(ch);
203 
204         /* foreach database ... */
205         while((path_fcodes = *dbv) != NULL) {
206                 dbv++;
207 
208                 if (!strcmp(path_fcodes, "-"))
209                         f_stdin = 1;
210 		else
211 			f_stdin = 0;
212 
213 #ifndef MMAP
214 		f_mmap = 0;	/* be paranoid */
215 #endif
216                 if (!f_mmap || f_stdin || f_statistic)
217 			search_fopen(path_fcodes, argv);
218                 else
219 			search_mmap(path_fcodes, argv);
220         }
221 
222         if (f_silent)
223                 print_matches(counter);
224         exit(0);
225 }
226 
227 
228 /*
229  * Arguments:
230  * db	database
231  * s	search strings
232  */
233 void
234 search_fopen(char *db, char **s)
235 {
236 	FILE *fp;
237 #ifdef DEBUG
238         long t0;
239 #endif
240 
241 	/* can only read stdin once */
242 	if (f_stdin) {
243 		fp = stdin;
244 		if (*(s+1) != NULL) {
245 			warnx("read database from stdin, use only `%s' as pattern", *s);
246 			*(s+1) = NULL;
247 		}
248 	}
249 	else if ((fp = fopen(db, "r")) == NULL)
250 		err(1,  "`%s'", db);
251 
252 	/* count only chars or lines */
253 	if (f_statistic) {
254 		statistic(fp, db);
255 		(void)fclose(fp);
256 		return;
257 	}
258 
259 	/* foreach search string ... */
260 	while(*s != NULL) {
261 #ifdef DEBUG
262 		t0 = cputime();
263 #endif
264 		if (!f_stdin &&
265 		    fseek(fp, (long)0, SEEK_SET) == -1)
266 			err(1, "fseek to begin of ``%s''\n", db);
267 
268 		if (f_icase)
269 			fastfind_icase(fp, *s, db);
270 		else
271 			fastfind(fp, *s, db);
272 #ifdef DEBUG
273 		warnx("fastfind %ld ms", cputime () - t0);
274 #endif
275 		s++;
276 	}
277 	(void)fclose(fp);
278 }
279 
280 #ifdef MMAP
281 /*
282  * Arguments:
283  * db	database
284  * s	search strings
285  */
286 void
287 search_mmap(char *db, char **s)
288 {
289         struct stat sb;
290         int fd;
291         caddr_t p;
292         off_t len;
293 #ifdef DEBUG
294         long t0;
295 #endif
296 	if ((fd = open(db, O_RDONLY)) == -1 ||
297 	    fstat(fd, &sb) == -1)
298 		err(1, "`%s'", db);
299 	len = sb.st_size;
300 	if (len < (2*NBG))
301 		errx(1,
302 		    "database too small: %s\nRun /usr/libexec/locate.updatedb",
303 		    db);
304 
305 	if ((p = mmap((caddr_t)0, (size_t)len,
306 		      PROT_READ, MAP_SHARED,
307 		      fd, (off_t)0)) == MAP_FAILED)
308 		err(1, "mmap ``%s''", db);
309 
310 	/* foreach search string ... */
311 	while (*s != NULL) {
312 #ifdef DEBUG
313 		t0 = cputime();
314 #endif
315 		if (f_icase)
316 			fastfind_mmap_icase(*s, p, (int)len, db);
317 		else
318 			fastfind_mmap(*s, p, (int)len, db);
319 #ifdef DEBUG
320 		warnx("fastfind %ld ms", cputime () - t0);
321 #endif
322 		s++;
323 	}
324 
325 	if (munmap(p, (size_t)len) == -1)
326 		warn("munmap %s\n", db);
327 
328 	(void)close(fd);
329 }
330 #endif /* MMAP */
331 
332 #ifdef DEBUG
333 unsigned long
334 cputime ()
335 {
336 	struct rusage rus;
337 
338 	getrusage(RUSAGE_SELF, &rus);
339 	return(rus.ru_utime.tv_sec * 1000 + rus.ru_utime.tv_usec / 1000);
340 }
341 #endif /* DEBUG */
342 
343 void
344 usage ()
345 {
346         (void)fprintf(stderr,
347 	"usage: locate [-0Scims] [-l limit] [-d database] pattern ...\n\n");
348         (void)fprintf(stderr,
349 	"default database: `%s' or $LOCATE_PATH\n", _PATH_FCODES);
350         exit(1);
351 }
352 
353 
354 /* load fastfind functions */
355 
356 /* statistic */
357 /* fastfind_mmap, fastfind_mmap_icase */
358 #ifdef MMAP
359 #undef FF_MMAP
360 #undef FF_ICASE
361 
362 #define FF_MMAP
363 #include "fastfind.c"
364 #define FF_ICASE
365 #include "fastfind.c"
366 #endif /* MMAP */
367 
368 /* fopen */
369 /* fastfind, fastfind_icase */
370 #undef FF_MMAP
371 #undef FF_ICASE
372 #include "fastfind.c"
373 #define FF_ICASE
374 #include "fastfind.c"
375