xref: /freebsd/usr.bin/locate/locate/fastfind.c (revision df7f5d4de4592a8948a25ce01e5bddfbb7ce39dc)
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  * $Id$
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 		     (float)(100 * (size + big - (2 * NBG))) / chars);
93 	(void)printf("Bigram: %2.2f%%, ", (float)(100 * (size - big)) / size);
94 	(void)printf("Total: %2.2f%%\n",
95 		     (float)(100 * (size - (2 * NBG))) / chars);
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 
107 void
108 #ifdef FF_MMAP
109 
110 
111 #ifdef FF_ICASE
112 fastfind_mmap_icase
113 #else
114 fastfind_mmap
115 #endif /* FF_ICASE */
116 (pathpart, paddr, len, database)
117 	char *pathpart; 	/* search string */
118 	caddr_t paddr;  	/* mmap pointer */
119 	int len;        	/* length of database */
120 	char *database; 	/* for error message */
121 
122 
123 #else /* MMAP */
124 
125 
126 #ifdef FF_ICASE
127 fastfind_icase
128 #else
129 fastfind
130 #endif /* FF_ICASE */
131 
132 (fp, pathpart, database)
133 	FILE *fp;               /* open database */
134 	char *pathpart;		/* search string */
135 	char *database;		/* for error message */
136 
137 
138 #endif /* MMAP */
139 
140 {
141 	register u_char *p, *s, *patend, *q, *foundchar;
142 	register int c, cc;
143 	int count, found, globflag;
144 	u_char *cutoff;
145 	u_char bigram1[NBG], bigram2[NBG], path[MAXPATHLEN];
146 
147 #ifdef FF_ICASE
148 	/* use a lookup table for case insensitive search */
149 	u_char table[UCHAR_MAX + 1];
150 
151 	tolower_word(pathpart);
152 #endif /* FF_ICASE*/
153 
154 	/* init bigram table */
155 #ifdef FF_MMAP
156 	if (len < (2*NBG)) {
157 		(void)fprintf(stderr, "database too small: %s\n", database);
158 		exit(1);
159 	}
160 
161 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++, len-= 2) {
162 		p[c] = check_bigram_char(*paddr++);
163 		s[c] = check_bigram_char(*paddr++);
164 	}
165 #else
166 	for (c = 0, p = bigram1, s = bigram2; c < NBG; c++) {
167 		p[c] = check_bigram_char(getc(fp));
168 		s[c] = check_bigram_char(getc(fp));
169 	}
170 #endif /* FF_MMAP */
171 
172 	/* find optimal (last) char for searching */
173 	for (p = pathpart; *p != '\0'; p++)
174 		if (index(LOCATE_REG, *p) != NULL)
175 			break;
176 
177 	if (*p == '\0')
178 		globflag = 0;
179 	else
180 		globflag = 1;
181 
182 	p = pathpart;
183 	patend = patprep(p);
184 	cc = *patend;
185 
186 #ifdef FF_ICASE
187 	/* set patend char to true */
188         for (c = 0; c < UCHAR_MAX + 1; c++)
189                 table[c] = 0;
190 
191 	table[TOLOWER(*patend)] = 1;
192 	table[toupper(*patend)] = 1;
193 #endif /* FF_ICASE */
194 
195 
196 	/* main loop */
197 	found = count = 0;
198 	foundchar = 0;
199 
200 #ifdef FF_MMAP
201 	c = (u_char)*paddr++; len--;
202 	for (; len > 0; ) {
203 #else
204 	c = getc(fp);
205 	for (; c != EOF; ) {
206 #endif /* FF_MMAP */
207 
208 		/* go forward or backward */
209 		if (c == SWITCH) { /* big step, an integer */
210 #ifdef FF_MMAP
211 			count += getwm(paddr) - OFFSET;
212 			len -= INTSIZE; paddr += INTSIZE;
213 #else
214 			count +=  getwf(fp) - OFFSET;
215 #endif /* FF_MMAP */
216 		} else {	   /* slow step, =< 14 chars */
217 			count += c - OFFSET;
218 		}
219 
220 		/* overlay old path */
221 		p = path + count;
222 		foundchar = p - 1;
223 
224 		for (;;) {
225 #ifdef FF_MMAP
226 			c = (u_char)*paddr++;
227 		        len--;
228 #else
229 			c = getc(fp);
230 #endif /* FF_MMAP */
231 			/*
232 			 * == UMLAUT: 8 bit char followed
233 			 * <= SWITCH: offset
234 			 * >= PARITY: bigram
235 			 * rest:      single ascii char
236 			 *
237 			 * offset < SWITCH < UMLAUT < ascii < PARITY < bigram
238 			 */
239 			if (c < PARITY) {
240 				if (c <= UMLAUT) {
241 					if (c == UMLAUT) {
242 #ifdef FF_MMAP
243 						c = (u_char)*paddr++;
244 						len--;
245 #else
246 						c = getc(fp);
247 #endif /* FF_MMAP */
248 
249 					} else
250 						break; /* SWITCH */
251 				}
252 #ifdef FF_ICASE
253 				if (table[c])
254 #else
255 				if (c == cc)
256 #endif /* FF_ICASE */
257 					foundchar = p;
258 				*p++ = c;
259 			}
260 			else {
261 				/* bigrams are parity-marked */
262 				TO7BIT(c);
263 
264 #ifndef FF_ICASE
265 				if (bigram1[c] == cc ||
266 				    bigram2[c] == cc)
267 #else
268 
269 					if (table[bigram1[c]] ||
270 					    table[bigram2[c]])
271 #endif /* FF_ICASE */
272 						foundchar = p + 1;
273 
274 				*p++ = bigram1[c];
275 				*p++ = bigram2[c];
276 			}
277 		}
278 
279 		if (found) {                     /* previous line matched */
280 			cutoff = path;
281 			*p-- = '\0';
282 			foundchar = p;
283 		} else if (foundchar >= path + count) { /* a char matched */
284 			*p-- = '\0';
285 			cutoff = path + count;
286 		} else                           /* nothing to do */
287 			continue;
288 
289 		found = 0;
290 		for (s = foundchar; s >= cutoff; s--) {
291 			if (*s == cc
292 #ifdef FF_ICASE
293 			    || TOLOWER(*s) == cc
294 #endif /* FF_ICASE */
295 			    ) {	/* fast first char check */
296 				for (p = patend - 1, q = s - 1; *p != '\0';
297 				     p--, q--)
298 					if (*q != *p
299 #ifdef FF_ICASE
300 					    && TOLOWER(*q) != *p
301 #endif /* FF_ICASE */
302 					    )
303 						break;
304 				if (*p == '\0') {   /* fast match success */
305 					found = 1;
306 					if (!globflag ||
307 #ifndef FF_ICASE
308 					    !fnmatch(pathpart, path, 0))
309 #else
310 					    !fnmatch(pathpart, path,
311 						     FNM_CASEFOLD))
312 #endif /* !FF_ICASE */
313 					{
314 						if (f_silent)
315 							counter++;
316 						else if (f_limit) {
317 							counter++;
318 							if (f_limit >= counter)
319 								(void)puts(path);
320 							else  {
321 								(void)fprintf(stderr, "[show only %d lines]\n", counter - 1);
322 								exit(0);
323 							}
324 						} else
325 							(void)puts(path);
326 					}
327 					break;
328 				}
329 			}
330 		}
331 	}
332 }
333