xref: /freebsd/usr.bin/locate/locate/fastfind.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1995-2022 Wolfram Schneider <wosch@FreeBSD.org>
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 
37 #ifndef _LOCATE_STATISTIC_
38 #define _LOCATE_STATISTIC_
39 
40 void
41 statistic (FILE *fp, char *path_fcodes)
42 {
43 	long lines, chars, size, size_nbg, big, zwerg, umlaut;
44 	u_char *p, *s;
45 	int c;
46 	int count, longest_path;
47 	int error = 0;
48 	u_char bigram1[NBG], bigram2[NBG], path[LOCATE_PATH_MAX];
49 
50 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++) {
51 		p[c] = check_bigram_char(getc(fp));
52 		s[c] = check_bigram_char(getc(fp));
53 	}
54 
55 	lines = chars = big = zwerg = umlaut = longest_path = 0;
56 	size = NBG + NBG;
57 
58 	for (c = getc(fp), count = 0; c != EOF; size++) {
59 		if (c == SWITCH) {
60 			count += getwf(fp) - OFFSET;
61 			size += sizeof(int);
62 			zwerg++;
63 		} else
64 			count += c - OFFSET;
65 
66 		if (count < 0 || count >= LOCATE_PATH_MAX) {
67 			/* stop on error and display the statstics anyway */
68 			warnx("corrupted database: %s %d", path_fcodes, count);
69 			error = 1;
70 			break;
71 		}
72 
73 		for (p = path + count; (c = getc(fp)) > SWITCH; size++)
74 			if (c < PARITY) {
75 				if (c == UMLAUT) {
76 					c = getc(fp);
77 					size++;
78 					umlaut++;
79 				}
80 				p++;
81 			} else {
82 				/* bigram char */
83 				big++;
84 				p += 2;
85 			}
86 
87 		p++;
88 		lines++;
89 		chars += (p - path);
90 		if ((p - path) > longest_path)
91 			longest_path = p - path;
92 	}
93 
94 	/* size without bigram db */
95 	size_nbg = size - (2 * NBG);
96 
97 	(void)printf("\nDatabase: %s\n", path_fcodes);
98 	(void)printf("Compression: Front: %2.2f%%, ", chars > 0 ?  (size_nbg + big) / (chars / (float)100) : 0);
99 	(void)printf("Bigram: %2.2f%%, ", big > 0 ? (size_nbg - big) / (size_nbg / (float)100) : 0);
100 	/* incl. bigram db overhead */
101 	(void)printf("Total: %2.2f%%\n", chars > 0 ?  size / (chars / (float)100) : 0);
102 	(void)printf("Filenames: %ld, ", lines);
103 	(void)printf("Characters: %ld, ", chars);
104 	(void)printf("Database size: %ld\n", size);
105 	(void)printf("Bigram characters: %ld, ", big);
106 	(void)printf("Integers: %ld, ", zwerg);
107 	(void)printf("8-Bit characters: %ld\n", umlaut);
108 	printf("Longest path: %d\n", longest_path > 0 ? longest_path - 1 : 0);
109 
110 	/* non zero exit on corrupt database */
111 	if (error)
112 		exit(error);
113 }
114 #endif /* _LOCATE_STATISTIC_ */
115 
116 extern	char	separator;
117 
118 void
119 #ifdef FF_MMAP
120 
121 
122 #ifdef FF_ICASE
123 fastfind_mmap_icase
124 #else
125 fastfind_mmap
126 #endif /* FF_ICASE */
127 (char *pathpart, caddr_t paddr, off_t len, char *database)
128 
129 
130 #else /* MMAP */
131 
132 
133 #ifdef FF_ICASE
134 fastfind_icase
135 #else
136 fastfind
137 #endif /* FF_ICASE */
138 
139 (FILE *fp, char *pathpart, char *database)
140 
141 
142 #endif /* MMAP */
143 
144 {
145 	u_char *p, *s, *patend, *q, *foundchar;
146 	int c, cc;
147 	int count, found, globflag;
148 	u_char *cutoff;
149 	u_char bigram1[NBG], bigram2[NBG], path[LOCATE_PATH_MAX + 2];
150 
151 #ifdef FF_ICASE
152 	/* use a lookup table for case insensitive search */
153 	u_char table[UCHAR_MAX + 1];
154 
155 	tolower_word(pathpart);
156 #endif /* FF_ICASE*/
157 
158 	/* init bigram table */
159 #ifdef FF_MMAP
160 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++, len-= 2) {
161 		p[c] = check_bigram_char(*paddr++);
162 		s[c] = check_bigram_char(*paddr++);
163 	}
164 #else
165 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++) {
166 		p[c] = check_bigram_char(getc(fp));
167 		s[c] = check_bigram_char(getc(fp));
168 	}
169 #endif /* FF_MMAP */
170 
171 	/* find optimal (last) char for searching */
172 	for (p = pathpart; *p != '\0'; p++)
173 		if (strchr(LOCATE_REG, *p) != NULL)
174 			break;
175 
176 	if (*p == '\0')
177 		globflag = 0;
178 	else
179 		globflag = 1;
180 
181 	p = pathpart;
182 	patend = patprep(p);
183 	cc = *patend;
184 
185 #ifdef FF_ICASE
186 	/* set patend char to true */
187         for (c = 0; c < UCHAR_MAX + 1; c++)
188                 table[c] = 0;
189 
190 	table[TOLOWER(*patend)] = 1;
191 	table[toupper(*patend)] = 1;
192 #endif /* FF_ICASE */
193 
194 
195 	/* main loop */
196 	found = count = 0;
197 	foundchar = 0;
198 
199 #ifdef FF_MMAP
200 	c = (u_char)*paddr++;
201 	len--;
202 
203 	for (; len > 0; ) {
204 #else
205 	c = getc(fp);
206 	for (; c != EOF; ) {
207 #endif /* FF_MMAP */
208 
209 		/* go forward or backward */
210 		if (c == SWITCH) { /* big step, an integer */
211 #ifdef FF_MMAP
212 			if (len < sizeof(int))
213 				errx(1, "corrupted database: %s", database);
214 
215 			count += getwm(paddr) - OFFSET;
216 			len -= INTSIZE;
217 			paddr += INTSIZE;
218 #else
219 			count +=  getwf(fp) - OFFSET;
220 #endif /* FF_MMAP */
221 		} else {	   /* slow step, =< 14 chars */
222 			count += c - OFFSET;
223 		}
224 
225 		if (count < 0 || count >= LOCATE_PATH_MAX)
226 			errx(1, "corrupted database: %s %d", database, count);
227 
228 		/* overlay old path */
229 		p = path + count;
230 		foundchar = p - 1;
231 
232 #ifdef FF_MMAP
233 		for (; len > 0;) {
234 			c = (u_char)*paddr++;
235 		        len--;
236 #else
237 		for (;;) {
238 			c = getc(fp);
239 #endif /* FF_MMAP */
240 			/*
241 			 * == UMLAUT: 8 bit char followed
242 			 * <= SWITCH: offset
243 			 * >= PARITY: bigram
244 			 * rest:      single ascii char
245 			 *
246 			 * offset < SWITCH < UMLAUT < ascii < PARITY < bigram
247 			 */
248 			if (c < PARITY) {
249 				if (c <= UMLAUT) {
250 					if (c == UMLAUT) {
251 #ifdef FF_MMAP
252 						c = (u_char)*paddr++;
253 						len--;
254 #else
255 						c = getc(fp);
256 #endif /* FF_MMAP */
257 
258 					} else
259 						break; /* SWITCH */
260 				}
261 #ifdef FF_ICASE
262 				if (table[c])
263 #else
264 				if (c == cc)
265 #endif /* FF_ICASE */
266 					foundchar = p;
267 				*p++ = c;
268 			}
269 			else {
270 				/* bigrams are parity-marked */
271 				TO7BIT(c);
272 
273 #ifndef FF_ICASE
274 				if (bigram1[c] == cc ||
275 				    bigram2[c] == cc)
276 #else
277 
278 					if (table[bigram1[c]] ||
279 					    table[bigram2[c]])
280 #endif /* FF_ICASE */
281 						foundchar = p + 1;
282 
283 				*p++ = bigram1[c];
284 				*p++ = bigram2[c];
285 			}
286 
287 			if (p - path >= LOCATE_PATH_MAX)
288 				errx(1, "corrupted database: %s %td", database, p - path);
289 
290 		}
291 
292 		if (found) {                     /* previous line matched */
293 			cutoff = path;
294 			*p-- = '\0';
295 			foundchar = p;
296 		} else if (foundchar >= path + count) { /* a char matched */
297 			*p-- = '\0';
298 			cutoff = path + count;
299 		} else                           /* nothing to do */
300 			continue;
301 
302 		found = 0;
303 		for (s = foundchar; s >= cutoff; s--) {
304 			if (*s == cc
305 #ifdef FF_ICASE
306 			    || TOLOWER(*s) == cc
307 #endif /* FF_ICASE */
308 			    ) {	/* fast first char check */
309 				for (p = patend - 1, q = s - 1; *p != '\0';
310 				     p--, q--)
311 					if (*q != *p
312 #ifdef FF_ICASE
313 					    && TOLOWER(*q) != *p
314 #endif /* FF_ICASE */
315 					    )
316 						break;
317 				if (*p == '\0') {   /* fast match success */
318 					found = 1;
319 					if (!globflag ||
320 #ifndef FF_ICASE
321 					    !fnmatch(pathpart, path, 0))
322 #else
323 					    !fnmatch(pathpart, path,
324 						     FNM_CASEFOLD))
325 #endif /* !FF_ICASE */
326 					{
327 						if (f_silent)
328 							counter++;
329 						else if (f_limit) {
330 							counter++;
331 							if (f_limit >= counter)
332 								(void)printf("%s%c",path,separator);
333 							else
334 								errx(0, "[show only %ld lines]", counter - 1);
335 						} else
336 							(void)printf("%s%c",path,separator);
337 					}
338 					break;
339 				}
340 			}
341 		}
342 	}
343 }
344