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 #if 0 41 #ifndef lint 42 static char copyright[] = 43 "@(#) Copyright (c) 1989, 1993\n\ 44 The Regents of the University of California. All rights reserved.\n"; 45 #endif /* not lint */ 46 47 #ifndef lint 48 static char sccsid[] = "@(#)locate.code.c 8.1 (Berkeley) 6/6/93"; 49 #endif /* not lint */ 50 #endif 51 52 /* 53 * PURPOSE: sorted list compressor (works with a modified 'find' 54 * to encode/decode a filename database) 55 * 56 * USAGE: bigram < list > bigrams 57 * process bigrams (see updatedb) > common_bigrams 58 * code common_bigrams < list > squozen_list 59 * 60 * METHOD: Uses 'front compression' (see ";login:", Volume 8, Number 1 61 * February/March 1983, p. 8). Output format is, per line, an 62 * offset differential count byte followed by a partially bigram- 63 * encoded ascii residue. A bigram is a two-character sequence, 64 * the first 128 most common of which are encoded in one byte. 65 * 66 * EXAMPLE: For simple front compression with no bigram encoding, 67 * if the input is... then the output is... 68 * 69 * /usr/src 0 /usr/src 70 * /usr/src/cmd/aardvark.c 8 /cmd/aardvark.c 71 * /usr/src/cmd/armadillo.c 14 armadillo.c 72 * /usr/tmp/zoo 5 tmp/zoo 73 * 74 * The codes are: 75 * 76 * 0-28 likeliest differential counts + offset to make nonnegative 77 * 30 switch code for out-of-range count to follow in next word 78 * 31 an 8 bit char followed 79 * 128-255 bigram codes (128 most common, as determined by 'updatedb') 80 * 32-127 single character (printable) ascii residue (ie, literal) 81 * 82 * The locate database store any character except newline ('\n') 83 * and NUL ('\0'). The 8-bit character support don't wast extra 84 * space until you have characters in file names less than 32 85 * or greather than 127. 86 * 87 * 88 * SEE ALSO: updatedb.sh, ../bigram/locate.bigram.c 89 * 90 * AUTHOR: James A. Woods, Informatics General Corp., 91 * NASA Ames Research Center, 10/82 92 * 8-bit file names characters: 93 * Wolfram Schneider, Berlin September 1996 94 */ 95 96 #include <sys/param.h> 97 #include <err.h> 98 #include <errno.h> 99 #include <stdlib.h> 100 #include <string.h> 101 #include <stdio.h> 102 #include <unistd.h> 103 #include "locate.h" 104 105 #define BGBUFSIZE (NBG * 2) /* size of bigram buffer */ 106 107 u_char buf1[MAXPATHLEN] = " "; 108 u_char buf2[MAXPATHLEN]; 109 u_char bigrams[BGBUFSIZE + 1] = { 0 }; 110 111 #define LOOKUP 1 /* use a lookup array instead a function, 3x faster */ 112 113 #ifdef LOOKUP 114 #define BGINDEX(x) (big[(u_char)*x][(u_char)*(x + 1)]) 115 typedef short bg_t; 116 bg_t big[UCHAR_MAX + 1][UCHAR_MAX + 1]; 117 #else 118 #define BGINDEX(x) bgindex(x) 119 typedef int bg_t; 120 int bgindex(char *); 121 #endif /* LOOKUP */ 122 123 124 void usage(void); 125 126 int 127 main(int argc, char *argv[]) 128 { 129 u_char *cp, *oldpath, *path; 130 int ch, code, count, diffcount, oldcount; 131 u_int i, j; 132 FILE *fp; 133 134 while ((ch = getopt(argc, argv, "")) != -1) 135 switch(ch) { 136 default: 137 usage(); 138 } 139 argc -= optind; 140 argv += optind; 141 142 if (argc != 1) 143 usage(); 144 145 if ((fp = fopen(argv[0], "r")) == NULL) 146 err(1, "%s", argv[0]); 147 148 /* First copy bigram array to stdout. */ 149 (void)fgets(bigrams, BGBUFSIZE + 1, fp); 150 151 if (fwrite(bigrams, 1, BGBUFSIZE, stdout) != BGBUFSIZE) 152 err(1, "stdout"); 153 (void)fclose(fp); 154 155 #ifdef LOOKUP 156 /* init lookup table */ 157 for (i = 0; i < UCHAR_MAX + 1; i++) 158 for (j = 0; j < UCHAR_MAX + 1; j++) 159 big[i][j] = (bg_t)-1; 160 161 for (cp = bigrams, i = 0; *cp != '\0'; i += 2, cp += 2) 162 big[(u_char)*cp][(u_char)*(cp + 1)] = (bg_t)i; 163 164 #endif /* LOOKUP */ 165 166 oldpath = buf1; 167 path = buf2; 168 oldcount = 0; 169 170 while (fgets(path, sizeof(buf2), stdin) != NULL) { 171 172 /* skip empty lines */ 173 if (*path == '\n') 174 continue; 175 176 /* remove newline */ 177 for (cp = path; *cp != '\0'; cp++) { 178 #ifndef LOCATE_CHAR30 179 /* old locate implementations core'd for char 30 */ 180 if (*cp == SWITCH) 181 *cp = '?'; 182 else 183 #endif /* !LOCATE_CHAR30 */ 184 185 /* chop newline */ 186 if (*cp == '\n') 187 *cp = '\0'; 188 } 189 190 /* Skip longest common prefix. */ 191 for (cp = path; *cp == *oldpath; cp++, oldpath++) 192 if (*cp == '\0') 193 break; 194 195 count = cp - path; 196 diffcount = count - oldcount + OFFSET; 197 oldcount = count; 198 if (diffcount < 0 || diffcount > 2 * OFFSET) { 199 if (putchar(SWITCH) == EOF || 200 putw(diffcount, stdout) == EOF) 201 err(1, "stdout"); 202 } else 203 if (putchar(diffcount) == EOF) 204 err(1, "stdout"); 205 206 while (*cp != '\0') { 207 /* print *two* characters */ 208 209 if ((code = BGINDEX(cp)) != (bg_t)-1) { 210 /* 211 * print *one* as bigram 212 * Found, so mark byte with 213 * parity bit. 214 */ 215 if (putchar((code / 2) | PARITY) == EOF) 216 err(1, "stdout"); 217 cp += 2; 218 } 219 220 else { 221 for (i = 0; i < 2; i++) { 222 if (*cp == '\0') 223 break; 224 225 /* print umlauts in file names */ 226 if (*cp < ASCII_MIN || 227 *cp > ASCII_MAX) { 228 if (putchar(UMLAUT) == EOF || 229 putchar(*cp++) == EOF) 230 err(1, "stdout"); 231 } 232 233 else { 234 /* normal character */ 235 if(putchar(*cp++) == EOF) 236 err(1, "stdout"); 237 } 238 } 239 240 } 241 } 242 243 if (path == buf1) { /* swap pointers */ 244 path = buf2; 245 oldpath = buf1; 246 } else { 247 path = buf1; 248 oldpath = buf2; 249 } 250 } 251 /* Non-zero status if there were errors */ 252 if (fflush(stdout) != 0 || ferror(stdout)) 253 exit(1); 254 exit(0); 255 } 256 257 #ifndef LOOKUP 258 int 259 bgindex(char *bg) /* Return location of bg in bigrams or -1. */ 260 { 261 char bg0, bg1, *p; 262 263 bg0 = bg[0]; 264 bg1 = bg[1]; 265 for (p = bigrams; *p != NULL; p++) 266 if (*p++ == bg0 && *p == bg1) 267 break; 268 return (*p == NULL ? -1 : (--p - bigrams)); 269 } 270 #endif /* !LOOKUP */ 271 272 void 273 usage(void) 274 { 275 (void)fprintf(stderr, 276 "usage: locate.code common_bigrams < list > squozen_list\n"); 277 exit(1); 278 } 279