xref: /freebsd/usr.bin/locate/locate/fastfind.c (revision e627b39baccd1ec9129690167cf5e6d860509655)
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  * $Id: fastfind.c,v 1.2 1996/08/29 22:39:41 wosch Exp wosch $
38  */
39 
40 
41 #ifndef _LOCATE_STATISTIC_
42 #define _LOCATE_STATISTIC_
43 
44 void
45 statistic (fp, path_fcodes)
46 	FILE *fp;               /* open database */
47 	char *path_fcodes;  	/* for error message */
48 {
49 	register int lines, chars, size, big;
50 	register u_char *p, *s;
51 	register int c;
52 	int count;
53 	u_char bigram1[NBG], bigram2[NBG], path[MAXPATHLEN];
54 
55 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++) {
56 		p[c] = check_bigram_char(getc(fp));
57 		s[c] = check_bigram_char(getc(fp));
58 	}
59 
60 	lines = chars = big = 0;
61 	size = NBG + NBG;
62 
63 	for (c = getc(fp), count = 0; c != EOF; size++) {
64 		if (c == SWITCH) {
65 			count += getwf(fp) - OFFSET;
66 			size += sizeof(int);
67 		} else
68 			count += c - OFFSET;
69 
70 		for (p = path + count; (c = getc(fp)) > SWITCH; size++)
71 			if (c < PARITY)
72 				p++;
73 			else {
74 				big++;
75 				p += 2;
76 			}
77 
78 		p++;
79 		lines++;
80 		chars += (p - path);
81 	}
82 
83 	(void)printf("\nDatabase: %s\n", path_fcodes);
84 	(void)printf("Compression: Front: %2.2f%%, ",
85 		     (float)(100 * (size + big)) / chars);
86 	(void)printf("Bigram: %2.2f%%, ", (float)(100 * (size - big)) / size);
87 	(void)printf("Total: %2.2f%%\n", (float)(100 * size) / chars);
88 	(void)printf("Filenames: %d, ", lines);
89 	(void)printf("Chars: %d\n", chars);
90 	(void)printf("Database size: %d, ", size);
91 	(void)printf("Bigram chars: %d\n", big);
92 
93 }
94 #endif /* _LOCATE_STATISTIC_ */
95 
96 
97 void
98 #ifdef FF_MMAP
99 
100 
101 #ifdef FF_ICASE
102 fastfind_mmap_icase
103 #else
104 fastfind_mmap
105 #endif
106 (pathpart, paddr, len, database)
107 	char *pathpart; 	/* search string */
108 	caddr_t paddr;  	/* mmap pointer */
109 	int len;        	/* length of database */
110 	char *database; 	/* for error message */
111 
112 
113 #else /* MMAP */
114 
115 
116 #ifdef FF_ICASE
117 fastfind_icase
118 #else /* !FF_ICASE */
119 fastfind
120 #endif /* FF_ICASE */
121 
122 (fp, pathpart, database)
123 	FILE *fp;               /* open database */
124 	char *pathpart;		/* search string */
125 	char *database;		/* for error message */
126 
127 
128 #endif /* MMAP */
129 
130 {
131 	register u_char *p, *s, *patend, *q, *foundchar;
132 	register int c, cc;
133 	int count, found, globflag;
134 	u_char *cutoff;
135 	u_char bigram1[NBG], bigram2[NBG], path[MAXPATHLEN];
136 
137 #ifdef FF_ICASE
138 	/* use a lookup table for case insensitive search */
139 	u_char table[UCHAR_MAX];
140 
141 	tolower_word(pathpart);
142 #endif
143 
144 	/* init bigram table */
145 #ifdef FF_MMAP
146 	if (len < (2*NBG)) {
147 		(void)fprintf(stderr, "database to small: %s\n", database);
148 		exit(1);
149 	}
150 
151 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++, len-= 2) {
152 		p[c] = check_bigram_char(*paddr++);
153 		s[c] = check_bigram_char(*paddr++);
154 	}
155 #else
156 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++) {
157 		p[c] = check_bigram_char(getc(fp));
158 		s[c] = check_bigram_char(getc(fp));
159 	}
160 #endif
161 
162 	/* find optimal (last) char for searching */
163 	p = pathpart;
164 	globflag = index(p, '*') || index(p, '?') || index(p, '[');
165 	patend = patprep(p);
166 	cc = *patend;
167 
168 #ifdef FF_ICASE
169 	/* set patend char to true */
170 	table[TOLOWER(*patend)] = 1;
171 	table[toupper(*patend)] = 1;
172 #endif
173 
174 
175 	/* main loop */
176 	found = count = 0;
177 	foundchar = 0;
178 
179 #ifdef FF_MMAP
180 	for (c = (u_char)*paddr++; len-- > 0; ) {
181 #else
182 	for (c = getc(fp); c != EOF; ) {
183 #endif
184 
185 		/* go forward or backward */
186 		if (c == SWITCH) { /* big step, an integer */
187 #ifdef FF_MMAP
188 			count += getwm(paddr) - OFFSET;
189 			len -= INTSIZE; paddr += INTSIZE;
190 #else
191 			count +=  getwf(fp) - OFFSET;
192 #endif
193 		} else {	   /* slow step, =< 14 chars */
194 			count += c - OFFSET;
195 		}
196 
197 		/* overlay old path */
198 		p = path + count;
199 		foundchar = p - 1;
200 #ifdef FF_MMAP
201 		for (; (c = (u_char)*paddr++) > SWITCH; len--)
202 #else
203 		for (; (c = getc(fp)) > SWITCH; )
204 #endif
205 
206 			if (c < PARITY) {
207 #ifdef FF_ICASE
208 				if (table[c])
209 #else
210 				if (c == cc)
211 #endif
212 					foundchar = p;
213 				*p++ = c;
214 			}
215 			else {
216 				/* bigrams are parity-marked */
217 				TO7BIT(c);
218 
219 #ifndef FF_ICASE
220 				if (bigram1[c] == cc ||
221 				    bigram2[c] == cc)
222 #else
223 
224 					if (table[bigram1[c]] ||
225 					    table[bigram2[c]])
226 #endif
227 						foundchar = p + 1;
228 
229 				*p++ = bigram1[c];
230 				*p++ = bigram2[c];
231 			}
232 
233 
234 		if (found) {                     /* previous line matched */
235 			cutoff = path;
236 			*p-- = '\0';
237 			foundchar = p;
238 		} else if (foundchar >= path + count) { /* a char matched */
239 			*p-- = '\0';
240 			cutoff = path + count;
241 		} else                           /* nothing to do */
242 			continue;
243 
244 		found = 0;
245 		for (s = foundchar; s >= cutoff; s--) {
246 			if (*s == cc
247 #ifdef FF_ICASE
248 			    || TOLOWER(*s) == cc
249 #endif
250 			    ) {	/* fast first char check */
251 				for (p = patend - 1, q = s - 1; *p != '\0';
252 				     p--, q--)
253 					if (*q != *p
254 #ifdef FF_ICASE
255 					    && TOLOWER(*q) != *p
256 #endif
257 					    )
258 						break;
259 				if (*p == '\0') {   /* fast match success */
260 					found = 1;
261 					if (!globflag || !fnmatch(pathpart, path, 0)) {
262 						if (f_silent)
263 							counter++;
264 						else if (f_limit) {
265 							counter++;
266 							if (f_limit >= counter)
267 								(void)puts(path);
268 							else  {
269 								(void)fprintf(stderr, "[show only %d lines]\n", counter - 1);
270 								exit(0);
271 							}
272 						} else
273 							(void)puts(path);
274 					}
275 					break;
276 				}
277 			}
278 		}
279 	}
280 }
281