xref: /freebsd/usr.bin/locate/locate/fastfind.c (revision e796cc77c586c2955b2f3940dbf4991b31e8d289)
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  * $FreeBSD$
40  */
41 
42 
43 #ifndef _LOCATE_STATISTIC_
44 #define _LOCATE_STATISTIC_
45 
46 void
47 statistic (fp, path_fcodes)
48 	FILE *fp;               /* open database */
49 	char *path_fcodes;  	/* for error message */
50 {
51 	register int lines, chars, size, big, zwerg;
52 	register u_char *p, *s;
53 	register int c;
54 	int count, umlaut;
55 	u_char bigram1[NBG], bigram2[NBG], path[MAXPATHLEN];
56 
57 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++) {
58 		p[c] = check_bigram_char(getc(fp));
59 		s[c] = check_bigram_char(getc(fp));
60 	}
61 
62 	lines = chars = big = zwerg = umlaut = 0;
63 	size = NBG + NBG;
64 
65 	for (c = getc(fp), count = 0; c != EOF; size++) {
66 		if (c == SWITCH) {
67 			count += getwf(fp) - OFFSET;
68 			size += sizeof(int);
69 			zwerg++;
70 		} else
71 			count += c - OFFSET;
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 	}
91 
92 	(void)printf("\nDatabase: %s\n", path_fcodes);
93 	(void)printf("Compression: Front: %2.2f%%, ",
94 		     (size + big - (2 * NBG)) / (chars / (float)100));
95 	(void)printf("Bigram: %2.2f%%, ", (size - big) / (size / (float)100));
96 	(void)printf("Total: %2.2f%%\n",
97 		     (size - (2 * NBG)) / (chars / (float)100));
98 	(void)printf("Filenames: %d, ", lines);
99 	(void)printf("Characters: %d, ", chars);
100 	(void)printf("Database size: %d\n", size);
101 	(void)printf("Bigram characters: %d, ", big);
102 	(void)printf("Integers: %d, ", zwerg);
103 	(void)printf("8-Bit characters: %d\n", umlaut);
104 
105 }
106 #endif /* _LOCATE_STATISTIC_ */
107 
108 extern	char	separator;
109 
110 void
111 #ifdef FF_MMAP
112 
113 
114 #ifdef FF_ICASE
115 fastfind_mmap_icase
116 #else
117 fastfind_mmap
118 #endif /* FF_ICASE */
119 (pathpart, paddr, len, database)
120 	char *pathpart; 	/* search string */
121 	caddr_t paddr;  	/* mmap pointer */
122 	int len;        	/* length of database */
123 	char *database; 	/* for error message */
124 
125 
126 #else /* MMAP */
127 
128 
129 #ifdef FF_ICASE
130 fastfind_icase
131 #else
132 fastfind
133 #endif /* FF_ICASE */
134 
135 (fp, pathpart, database)
136 	FILE *fp;               /* open database */
137 	char *pathpart;		/* search string */
138 	char *database;		/* for error message */
139 
140 
141 #endif /* MMAP */
142 
143 {
144 	register u_char *p, *s, *patend, *q, *foundchar;
145 	register int c, cc;
146 	int count, found, globflag;
147 	u_char *cutoff;
148 	u_char bigram1[NBG], bigram2[NBG], path[MAXPATHLEN];
149 
150 #ifdef FF_ICASE
151 	/* use a lookup table for case insensitive search */
152 	u_char table[UCHAR_MAX + 1];
153 
154 	tolower_word(pathpart);
155 #endif /* FF_ICASE*/
156 
157 	/* init bigram table */
158 #ifdef FF_MMAP
159 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++, len-= 2) {
160 		p[c] = check_bigram_char(*paddr++);
161 		s[c] = check_bigram_char(*paddr++);
162 	}
163 #else
164 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++) {
165 		p[c] = check_bigram_char(getc(fp));
166 		s[c] = check_bigram_char(getc(fp));
167 	}
168 #endif /* FF_MMAP */
169 
170 	/* find optimal (last) char for searching */
171 	for (p = pathpart; *p != '\0'; p++)
172 		if (strchr(LOCATE_REG, *p) != NULL)
173 			break;
174 
175 	if (*p == '\0')
176 		globflag = 0;
177 	else
178 		globflag = 1;
179 
180 	p = pathpart;
181 	patend = patprep(p);
182 	cc = *patend;
183 
184 #ifdef FF_ICASE
185 	/* set patend char to true */
186         for (c = 0; c < UCHAR_MAX + 1; c++)
187                 table[c] = 0;
188 
189 	table[TOLOWER(*patend)] = 1;
190 	table[toupper(*patend)] = 1;
191 #endif /* FF_ICASE */
192 
193 
194 	/* main loop */
195 	found = count = 0;
196 	foundchar = 0;
197 
198 #ifdef FF_MMAP
199 	c = (u_char)*paddr++; len--;
200 	for (; len > 0; ) {
201 #else
202 	c = getc(fp);
203 	for (; c != EOF; ) {
204 #endif /* FF_MMAP */
205 
206 		/* go forward or backward */
207 		if (c == SWITCH) { /* big step, an integer */
208 #ifdef FF_MMAP
209 			count += getwm(paddr) - OFFSET;
210 			len -= INTSIZE; paddr += INTSIZE;
211 #else
212 			count +=  getwf(fp) - OFFSET;
213 #endif /* FF_MMAP */
214 		} else {	   /* slow step, =< 14 chars */
215 			count += c - OFFSET;
216 		}
217 
218 		if (count < 0 || count > MAXPATHLEN)
219 			errx(1, "corrupted database: %s", database);
220 		/* overlay old path */
221 		p = path + count;
222 		foundchar = p - 1;
223 
224 #ifdef FF_MMAP
225 		for (; len > 0;) {
226 			c = (u_char)*paddr++;
227 		        len--;
228 #else
229 		for (;;) {
230 			c = getc(fp);
231 #endif /* FF_MMAP */
232 			/*
233 			 * == UMLAUT: 8 bit char followed
234 			 * <= SWITCH: offset
235 			 * >= PARITY: bigram
236 			 * rest:      single ascii char
237 			 *
238 			 * offset < SWITCH < UMLAUT < ascii < PARITY < bigram
239 			 */
240 			if (c < PARITY) {
241 				if (c <= UMLAUT) {
242 					if (c == UMLAUT) {
243 #ifdef FF_MMAP
244 						c = (u_char)*paddr++;
245 						len--;
246 #else
247 						c = getc(fp);
248 #endif /* FF_MMAP */
249 
250 					} else
251 						break; /* SWITCH */
252 				}
253 #ifdef FF_ICASE
254 				if (table[c])
255 #else
256 				if (c == cc)
257 #endif /* FF_ICASE */
258 					foundchar = p;
259 				*p++ = c;
260 			}
261 			else {
262 				/* bigrams are parity-marked */
263 				TO7BIT(c);
264 
265 #ifndef FF_ICASE
266 				if (bigram1[c] == cc ||
267 				    bigram2[c] == cc)
268 #else
269 
270 					if (table[bigram1[c]] ||
271 					    table[bigram2[c]])
272 #endif /* FF_ICASE */
273 						foundchar = p + 1;
274 
275 				*p++ = bigram1[c];
276 				*p++ = bigram2[c];
277 			}
278 		}
279 
280 		if (found) {                     /* previous line matched */
281 			cutoff = path;
282 			*p-- = '\0';
283 			foundchar = p;
284 		} else if (foundchar >= path + count) { /* a char matched */
285 			*p-- = '\0';
286 			cutoff = path + count;
287 		} else                           /* nothing to do */
288 			continue;
289 
290 		found = 0;
291 		for (s = foundchar; s >= cutoff; s--) {
292 			if (*s == cc
293 #ifdef FF_ICASE
294 			    || TOLOWER(*s) == cc
295 #endif /* FF_ICASE */
296 			    ) {	/* fast first char check */
297 				for (p = patend - 1, q = s - 1; *p != '\0';
298 				     p--, q--)
299 					if (*q != *p
300 #ifdef FF_ICASE
301 					    && TOLOWER(*q) != *p
302 #endif /* FF_ICASE */
303 					    )
304 						break;
305 				if (*p == '\0') {   /* fast match success */
306 					found = 1;
307 					if (!globflag ||
308 #ifndef FF_ICASE
309 					    !fnmatch(pathpart, path, 0))
310 #else
311 					    !fnmatch(pathpart, path,
312 						     FNM_CASEFOLD))
313 #endif /* !FF_ICASE */
314 					{
315 						if (f_silent)
316 							counter++;
317 						else if (f_limit) {
318 							counter++;
319 							if (f_limit >= counter)
320 								(void)printf("%s%c",path,separator);
321 							else
322 								errx(0, "[show only %d lines]", counter - 1);
323 						} else
324 							(void)printf("%s%c",path,separator);
325 					}
326 					break;
327 				}
328 			}
329 		}
330 	}
331 }
332