xref: /freebsd/usr.bin/locate/locate/fastfind.c (revision 4c8945a06b01a5c8122cdeb402af36bb46a06acc)
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  * $FreeBSD$
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, zwerg;
50 	register u_char *p, *s;
51 	register int c;
52 	int count, umlaut;
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 = zwerg = umlaut = 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 			zwerg++;
68 		} else
69 			count += c - OFFSET;
70 
71 		for (p = path + count; (c = getc(fp)) > SWITCH; size++)
72 			if (c < PARITY) {
73 				if (c == UMLAUT) {
74 					c = getc(fp);
75 					size++;
76 					umlaut++;
77 				}
78 				p++;
79 			} else {
80 				/* bigram char */
81 				big++;
82 				p += 2;
83 			}
84 
85 		p++;
86 		lines++;
87 		chars += (p - path);
88 	}
89 
90 	(void)printf("\nDatabase: %s\n", path_fcodes);
91 	(void)printf("Compression: Front: %2.2f%%, ",
92 		     (size + big - (2 * NBG)) / (chars / (float)100));
93 	(void)printf("Bigram: %2.2f%%, ", (size - big) / (size / (float)100));
94 	(void)printf("Total: %2.2f%%\n",
95 		     (size - (2 * NBG)) / (chars / (float)100));
96 	(void)printf("Filenames: %d, ", lines);
97 	(void)printf("Characters: %d, ", chars);
98 	(void)printf("Database size: %d\n", size);
99 	(void)printf("Bigram characters: %d, ", big);
100 	(void)printf("Integers: %d, ", zwerg);
101 	(void)printf("8-Bit characters: %d\n", umlaut);
102 
103 }
104 #endif /* _LOCATE_STATISTIC_ */
105 
106 extern	char	separator;
107 
108 void
109 #ifdef FF_MMAP
110 
111 
112 #ifdef FF_ICASE
113 fastfind_mmap_icase
114 #else
115 fastfind_mmap
116 #endif /* FF_ICASE */
117 (pathpart, paddr, len, database)
118 	char *pathpart; 	/* search string */
119 	caddr_t paddr;  	/* mmap pointer */
120 	int len;        	/* length of database */
121 	char *database; 	/* for error message */
122 
123 
124 #else /* MMAP */
125 
126 
127 #ifdef FF_ICASE
128 fastfind_icase
129 #else
130 fastfind
131 #endif /* FF_ICASE */
132 
133 (fp, pathpart, database)
134 	FILE *fp;               /* open database */
135 	char *pathpart;		/* search string */
136 	char *database;		/* for error message */
137 
138 
139 #endif /* MMAP */
140 
141 {
142 	register u_char *p, *s, *patend, *q, *foundchar;
143 	register int c, cc;
144 	int count, found, globflag;
145 	u_char *cutoff;
146 	u_char bigram1[NBG], bigram2[NBG], path[MAXPATHLEN];
147 
148 #ifdef FF_ICASE
149 	/* use a lookup table for case insensitive search */
150 	u_char table[UCHAR_MAX + 1];
151 
152 	tolower_word(pathpart);
153 #endif /* FF_ICASE*/
154 
155 	/* init bigram table */
156 #ifdef FF_MMAP
157 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++, len-= 2) {
158 		p[c] = check_bigram_char(*paddr++);
159 		s[c] = check_bigram_char(*paddr++);
160 	}
161 #else
162 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++) {
163 		p[c] = check_bigram_char(getc(fp));
164 		s[c] = check_bigram_char(getc(fp));
165 	}
166 #endif /* FF_MMAP */
167 
168 	/* find optimal (last) char for searching */
169 	for (p = pathpart; *p != '\0'; p++)
170 		if (index(LOCATE_REG, *p) != NULL)
171 			break;
172 
173 	if (*p == '\0')
174 		globflag = 0;
175 	else
176 		globflag = 1;
177 
178 	p = pathpart;
179 	patend = patprep(p);
180 	cc = *patend;
181 
182 #ifdef FF_ICASE
183 	/* set patend char to true */
184         for (c = 0; c < UCHAR_MAX + 1; c++)
185                 table[c] = 0;
186 
187 	table[TOLOWER(*patend)] = 1;
188 	table[toupper(*patend)] = 1;
189 #endif /* FF_ICASE */
190 
191 
192 	/* main loop */
193 	found = count = 0;
194 	foundchar = 0;
195 
196 #ifdef FF_MMAP
197 	c = (u_char)*paddr++; len--;
198 	for (; len > 0; ) {
199 #else
200 	c = getc(fp);
201 	for (; c != EOF; ) {
202 #endif /* FF_MMAP */
203 
204 		/* go forward or backward */
205 		if (c == SWITCH) { /* big step, an integer */
206 #ifdef FF_MMAP
207 			count += getwm(paddr) - OFFSET;
208 			len -= INTSIZE; paddr += INTSIZE;
209 #else
210 			count +=  getwf(fp) - OFFSET;
211 #endif /* FF_MMAP */
212 		} else {	   /* slow step, =< 14 chars */
213 			count += c - OFFSET;
214 		}
215 
216 		if (count < 0 || count > MAXPATHLEN)
217 			errx(1, "corrupted database: %s", database);
218 		/* overlay old path */
219 		p = path + count;
220 		foundchar = p - 1;
221 
222 #ifdef FF_MMAP
223 		for (; len > 0;) {
224 			c = (u_char)*paddr++;
225 		        len--;
226 #else
227 		for (;;) {
228 			c = getc(fp);
229 #endif /* FF_MMAP */
230 			/*
231 			 * == UMLAUT: 8 bit char followed
232 			 * <= SWITCH: offset
233 			 * >= PARITY: bigram
234 			 * rest:      single ascii char
235 			 *
236 			 * offset < SWITCH < UMLAUT < ascii < PARITY < bigram
237 			 */
238 			if (c < PARITY) {
239 				if (c <= UMLAUT) {
240 					if (c == UMLAUT) {
241 #ifdef FF_MMAP
242 						c = (u_char)*paddr++;
243 						len--;
244 #else
245 						c = getc(fp);
246 #endif /* FF_MMAP */
247 
248 					} else
249 						break; /* SWITCH */
250 				}
251 #ifdef FF_ICASE
252 				if (table[c])
253 #else
254 				if (c == cc)
255 #endif /* FF_ICASE */
256 					foundchar = p;
257 				*p++ = c;
258 			}
259 			else {
260 				/* bigrams are parity-marked */
261 				TO7BIT(c);
262 
263 #ifndef FF_ICASE
264 				if (bigram1[c] == cc ||
265 				    bigram2[c] == cc)
266 #else
267 
268 					if (table[bigram1[c]] ||
269 					    table[bigram2[c]])
270 #endif /* FF_ICASE */
271 						foundchar = p + 1;
272 
273 				*p++ = bigram1[c];
274 				*p++ = bigram2[c];
275 			}
276 		}
277 
278 		if (found) {                     /* previous line matched */
279 			cutoff = path;
280 			*p-- = '\0';
281 			foundchar = p;
282 		} else if (foundchar >= path + count) { /* a char matched */
283 			*p-- = '\0';
284 			cutoff = path + count;
285 		} else                           /* nothing to do */
286 			continue;
287 
288 		found = 0;
289 		for (s = foundchar; s >= cutoff; s--) {
290 			if (*s == cc
291 #ifdef FF_ICASE
292 			    || TOLOWER(*s) == cc
293 #endif /* FF_ICASE */
294 			    ) {	/* fast first char check */
295 				for (p = patend - 1, q = s - 1; *p != '\0';
296 				     p--, q--)
297 					if (*q != *p
298 #ifdef FF_ICASE
299 					    && TOLOWER(*q) != *p
300 #endif /* FF_ICASE */
301 					    )
302 						break;
303 				if (*p == '\0') {   /* fast match success */
304 					found = 1;
305 					if (!globflag ||
306 #ifndef FF_ICASE
307 					    !fnmatch(pathpart, path, 0))
308 #else
309 					    !fnmatch(pathpart, path,
310 						     FNM_CASEFOLD))
311 #endif /* !FF_ICASE */
312 					{
313 						if (f_silent)
314 							counter++;
315 						else if (f_limit) {
316 							counter++;
317 							if (f_limit >= counter)
318 								(void)printf("%s%c",path,separator);
319 							else
320 								errx(0, "[show only %d lines]", counter - 1);
321 						} else
322 							(void)printf("%s%c",path,separator);
323 					}
324 					break;
325 				}
326 			}
327 		}
328 	}
329 }
330