xref: /freebsd-14.2/usr.bin/locate/locate/locate.c (revision 260bab9f)
1 /*
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1995-2022 Wolfram Schneider <[email protected]>
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. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static const char copyright[] =
38 "@(#) Copyright (c) 1995-1996 Wolfram Schneider, Berlin.\n\
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 #if 0
45 static char sccsid[] = "@(#)locate.c    8.1 (Berkeley) 6/6/93";
46 #endif
47 #endif /* not lint */
48 
49 /*
50  * Ref: Usenix ;login:, Vol 8, No 1, February/March, 1983, p. 8.
51  *
52  * Locate scans a file list for the full pathname of a file given only part
53  * of the name.  The list has been processed with with "front-compression"
54  * and bigram coding.  Front compression reduces space by a factor of 4-5,
55  * bigram coding by a further 20-25%.
56  *
57  * The codes are:
58  *
59  *      0-28    likeliest differential counts + offset to make nonnegative
60  *      30      switch code for out-of-range count to follow in next word
61  *      31      an 8 bit char followed
62  *      128-255 bigram codes (128 most common, as determined by 'updatedb')
63  *      32-127  single character (printable) ascii residue (ie, literal)
64  *
65  * A novel two-tiered string search technique is employed:
66  *
67  * First, a metacharacter-free subpattern and partial pathname is matched
68  * BACKWARDS to avoid full expansion of the pathname list.  The time savings
69  * is 40-50% over forward matching, which cannot efficiently handle
70  * overlapped search patterns and compressed path residue.
71  *
72  * Then, the actual shell glob-style regular expression (if in this form) is
73  * matched against the candidate pathnames using the slower routines provided
74  * in the standard 'find'.
75  */
76 
77 #include <sys/param.h>
78 #include <ctype.h>
79 #include <err.h>
80 #include <fnmatch.h>
81 #include <locale.h>
82 #include <stdio.h>
83 #include <stdlib.h>
84 #include <string.h>
85 #include <unistd.h>
86 
87 #ifdef MMAP
88 #  include <sys/types.h>
89 #  include <sys/stat.h>
90 #  include <sys/mman.h>
91 #  include <fcntl.h>
92 #endif
93 
94 #include "locate.h"
95 #include "pathnames.h"
96 
97 
98 int f_mmap;             /* use mmap */
99 int f_icase;            /* ignore case */
100 int f_stdin;            /* read database from stdin */
101 int f_statistic;        /* print statistic */
102 int f_silent;           /* suppress output, show only count of matches */
103 long f_limit;           /* limit number of output lines, 0 == infinite */
104 long counter;           /* counter for matches [-c] */
105 char separator='\n';	/* line separator */
106 
107 u_char myctype[UCHAR_MAX + 1];
108 
109 void    usage(void);
110 void    statistic(FILE *, char *);
111 void    fastfind(FILE *, char *, char *);
112 void    fastfind_icase(FILE *, char *, char *);
113 void    fastfind_mmap(char *, caddr_t, off_t, char *);
114 void    fastfind_mmap_icase(char *, caddr_t, off_t, char *);
115 void	search_mmap(char *, char **);
116 void	search_fopen(char *, char **);
117 unsigned long cputime(void);
118 
119 extern char     **colon(char **, char*, char*);
120 extern int      getwm(caddr_t);
121 extern int      getwf(FILE *);
122 extern u_char   *tolower_word(u_char *);
123 extern int	check_bigram_char(int);
124 extern char 	*patprep(char *);
125 extern void 	rebuild_message(char *db);
126 extern int 	check_size(char *db);
127 
128 int
main(int argc,char ** argv)129 main(int argc, char **argv)
130 {
131         int ch;
132         char **dbv = NULL;
133 	char *path_fcodes;      /* locate database */
134 #ifdef MMAP
135         f_mmap = 1;		/* mmap is default */
136 #endif
137 	(void) setlocale(LC_ALL, "");
138 
139         while ((ch = getopt(argc, argv, "0Scd:il:ms")) != -1)
140                 switch(ch) {
141                 case '0':	/* 'find -print0' style */
142 			separator = '\0';
143 			break;
144                 case 'S':	/* statistic lines */
145                         f_statistic = 1;
146                         break;
147                 case 'l': /* limit number of output lines, 0 == infinite */
148                         f_limit = atol(optarg);
149 			if (f_limit < 0 )
150 				errx(1, "invalid argument for -l: '%s'", optarg);
151                         break;
152                 case 'd':	/* database */
153                         dbv = colon(dbv, optarg, _PATH_FCODES);
154                         break;
155                 case 'i':	/* ignore case */
156                         f_icase = 1;
157                         break;
158                 case 'm':	/* mmap */
159 #ifdef MMAP
160                         f_mmap = 1;
161 #else
162 						warnx("mmap(2) not implemented");
163 #endif
164                         break;
165                 case 's':	/* stdio lib */
166                         f_mmap = 0;
167                         break;
168                 case 'c': /* suppress output, show only count of matches */
169                         f_silent = 1;
170                         break;
171                 default:
172                         usage();
173                 }
174         argv += optind;
175         argc -= optind;
176 
177         /* to few arguments */
178         if (argc < 1 && !(f_statistic))
179                 usage();
180 
181         /* no (valid) database as argument */
182         if (dbv == NULL || *dbv == NULL) {
183                 /* try to read database from environment */
184                 if ((path_fcodes = getenv("LOCATE_PATH")) == NULL ||
185 		     *path_fcodes == '\0')
186                         /* use default database */
187                         dbv = colon(dbv, _PATH_FCODES, _PATH_FCODES);
188                 else		/* $LOCATE_PATH */
189                         dbv = colon(dbv, path_fcodes, _PATH_FCODES);
190         }
191 
192         if (f_icase && UCHAR_MAX < 4096) /* init tolower lookup table */
193                 for (ch = 0; ch < UCHAR_MAX + 1; ch++)
194                         myctype[ch] = tolower(ch);
195 
196         /* foreach database ... */
197         while((path_fcodes = *dbv) != NULL) {
198                 dbv++;
199 
200                 if (!strcmp(path_fcodes, "-"))
201                         f_stdin = 1;
202 		else
203 			f_stdin = 0;
204 
205 #ifndef MMAP
206 		f_mmap = 0;	/* be paranoid */
207 #endif
208                 if (!f_mmap || f_stdin || f_statistic)
209 			search_fopen(path_fcodes, argv);
210                 else
211 			search_mmap(path_fcodes, argv);
212         }
213 
214         if (f_silent)
215 		printf("%ld\n", counter);
216         exit(0);
217 }
218 
219 /*
220  * Arguments:
221  * db	database
222  * s	search strings
223  */
224 void
search_fopen(char * db,char ** s)225 search_fopen(char *db, char **s)
226 {
227 	FILE *fp;
228 
229 	/* can only read stdin once */
230 	if (f_stdin) {
231 		fp = stdin;
232 		if (*(s+1) != NULL) {
233 			warnx("read database from stdin, use only `%s' as pattern", *s);
234 			*(s+1) = NULL;
235 		}
236 	}
237 	else {
238 		if (!check_size(db))
239 			exit(1);
240 
241 		if ((fp = fopen(db, "r")) == NULL) {
242 			warn("`%s'", db);
243 			rebuild_message(db);
244 			exit(1);
245 		}
246 	}
247 
248 	/* count only chars or lines */
249 	if (f_statistic) {
250 		statistic(fp, db);
251 		(void)fclose(fp);
252 		return;
253 	}
254 
255 	/* foreach search string ... */
256 	while(*s != NULL) {
257 		if (!f_stdin &&
258 		    fseek(fp, (long)0, SEEK_SET) == -1)
259 			err(1, "fseek to begin of ``%s''\n", db);
260 
261 		if (f_icase)
262 			fastfind_icase(fp, *s, db);
263 		else
264 			fastfind(fp, *s, db);
265 		s++;
266 	}
267 	(void)fclose(fp);
268 }
269 
270 #ifdef MMAP
271 /*
272  * Arguments:
273  * db	database
274  * s	search strings
275  */
276 void
search_mmap(char * db,char ** s)277 search_mmap(char *db, char **s)
278 {
279         struct stat sb;
280         int fd;
281         caddr_t p;
282         off_t len;
283 
284 	if (!check_size(db))
285 		exit(1);
286 
287 	if (stat(db, &sb) == -1)
288 		err(1, "stat");
289 
290 	len = sb.st_size;
291 
292 	if ((fd = open(db, O_RDONLY)) == -1) {
293 		warn("%s", db);
294 		rebuild_message(db);
295 		exit(1);
296         }
297 
298 	if ((p = mmap((caddr_t)0, (size_t)len,
299 		      PROT_READ, MAP_SHARED,
300 		      fd, (off_t)0)) == MAP_FAILED)
301 		err(1, "mmap ``%s''", db);
302 
303 	/* foreach search string ... */
304 	while (*s != NULL) {
305 		if (f_icase)
306 			fastfind_mmap_icase(*s, p, len, db);
307 		else
308 			fastfind_mmap(*s, p, len, db);
309 		s++;
310 	}
311 
312 	if (munmap(p, (size_t)len) == -1)
313 		warn("munmap %s\n", db);
314 
315 	(void)close(fd);
316 }
317 #endif /* MMAP */
318 
319 void
usage()320 usage ()
321 {
322         (void)fprintf(stderr,
323 	"usage: locate [-0Scims] [-l limit] [-d database] pattern ...\n\n");
324         (void)fprintf(stderr,
325 	"default database: `%s' or $LOCATE_PATH\n", _PATH_FCODES);
326         exit(1);
327 }
328 
329 
330 /* load fastfind functions */
331 
332 /* statistic */
333 /* fastfind_mmap, fastfind_mmap_icase */
334 #ifdef MMAP
335 #undef FF_MMAP
336 #undef FF_ICASE
337 
338 #define FF_MMAP
339 #include "fastfind.c"
340 #define FF_ICASE
341 #include "fastfind.c"
342 #endif /* MMAP */
343 
344 /* fopen */
345 /* fastfind, fastfind_icase */
346 #undef FF_MMAP
347 #undef FF_ICASE
348 #include "fastfind.c"
349 #define FF_ICASE
350 #include "fastfind.c"
351