/usr.bin/locate/code/locate.code.c
https://bitbucket.org/freebsd/freebsd-head/ · C · 278 lines · 145 code · 36 blank · 97 comment · 65 complexity · 4e33fe891220161054572b17dd301b98 MD5 · raw file
- /*
- * Copyright (c) 1995 Wolfram Schneider <wosch@FreeBSD.org>. Berlin.
- * Copyright (c) 1989, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * James A. Woods.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * $FreeBSD$
- */
- #if 0
- #ifndef lint
- static char copyright[] =
- "@(#) Copyright (c) 1989, 1993\n\
- The Regents of the University of California. All rights reserved.\n";
- #endif /* not lint */
- #ifndef lint
- static char sccsid[] = "@(#)locate.code.c 8.1 (Berkeley) 6/6/93";
- #endif /* not lint */
- #endif
- /*
- * PURPOSE: sorted list compressor (works with a modified 'find'
- * to encode/decode a filename database)
- *
- * USAGE: bigram < list > bigrams
- * process bigrams (see updatedb) > common_bigrams
- * code common_bigrams < list > squozen_list
- *
- * METHOD: Uses 'front compression' (see ";login:", Volume 8, Number 1
- * February/March 1983, p. 8). Output format is, per line, an
- * offset differential count byte followed by a partially bigram-
- * encoded ascii residue. A bigram is a two-character sequence,
- * the first 128 most common of which are encoded in one byte.
- *
- * EXAMPLE: For simple front compression with no bigram encoding,
- * if the input is... then the output is...
- *
- * /usr/src 0 /usr/src
- * /usr/src/cmd/aardvark.c 8 /cmd/aardvark.c
- * /usr/src/cmd/armadillo.c 14 armadillo.c
- * /usr/tmp/zoo 5 tmp/zoo
- *
- * The codes are:
- *
- * 0-28 likeliest differential counts + offset to make nonnegative
- * 30 switch code for out-of-range count to follow in next word
- * 31 an 8 bit char followed
- * 128-255 bigram codes (128 most common, as determined by 'updatedb')
- * 32-127 single character (printable) ascii residue (ie, literal)
- *
- * The locate database store any character except newline ('\n')
- * and NUL ('\0'). The 8-bit character support don't wast extra
- * space until you have characters in file names less than 32
- * or greather than 127.
- *
- *
- * SEE ALSO: updatedb.sh, ../bigram/locate.bigram.c
- *
- * AUTHOR: James A. Woods, Informatics General Corp.,
- * NASA Ames Research Center, 10/82
- * 8-bit file names characters:
- * Wolfram Schneider, Berlin September 1996
- */
- #include <sys/param.h>
- #include <err.h>
- #include <errno.h>
- #include <stdlib.h>
- #include <string.h>
- #include <stdio.h>
- #include <unistd.h>
- #include "locate.h"
- #define BGBUFSIZE (NBG * 2) /* size of bigram buffer */
- u_char buf1[MAXPATHLEN] = " ";
- u_char buf2[MAXPATHLEN];
- u_char bigrams[BGBUFSIZE + 1] = { 0 };
- #define LOOKUP 1 /* use a lookup array instead a function, 3x faster */
- #ifdef LOOKUP
- #define BGINDEX(x) (big[(u_char)*x][(u_char)*(x + 1)])
- typedef short bg_t;
- bg_t big[UCHAR_MAX + 1][UCHAR_MAX + 1];
- #else
- #define BGINDEX(x) bgindex(x)
- typedef int bg_t;
- int bgindex(char *);
- #endif /* LOOKUP */
- void usage(void);
- int
- main(int argc, char *argv[])
- {
- u_char *cp, *oldpath, *path;
- int ch, code, count, diffcount, oldcount;
- u_int i, j;
- FILE *fp;
- while ((ch = getopt(argc, argv, "")) != -1)
- switch(ch) {
- default:
- usage();
- }
- argc -= optind;
- argv += optind;
- if (argc != 1)
- usage();
- if ((fp = fopen(argv[0], "r")) == NULL)
- err(1, "%s", argv[0]);
- /* First copy bigram array to stdout. */
- (void)fgets(bigrams, BGBUFSIZE + 1, fp);
- if (fwrite(bigrams, 1, BGBUFSIZE, stdout) != BGBUFSIZE)
- err(1, "stdout");
- (void)fclose(fp);
- #ifdef LOOKUP
- /* init lookup table */
- for (i = 0; i < UCHAR_MAX + 1; i++)
- for (j = 0; j < UCHAR_MAX + 1; j++)
- big[i][j] = (bg_t)-1;
- for (cp = bigrams, i = 0; *cp != '\0'; i += 2, cp += 2)
- big[(u_char)*cp][(u_char)*(cp + 1)] = (bg_t)i;
- #endif /* LOOKUP */
- oldpath = buf1;
- path = buf2;
- oldcount = 0;
- while (fgets(path, sizeof(buf2), stdin) != NULL) {
- /* skip empty lines */
- if (*path == '\n')
- continue;
- /* remove newline */
- for (cp = path; *cp != '\0'; cp++) {
- #ifndef LOCATE_CHAR30
- /* old locate implementations core'd for char 30 */
- if (*cp == SWITCH)
- *cp = '?';
- else
- #endif /* !LOCATE_CHAR30 */
- /* chop newline */
- if (*cp == '\n')
- *cp = '\0';
- }
- /* Skip longest common prefix. */
- for (cp = path; *cp == *oldpath; cp++, oldpath++)
- if (*cp == '\0')
- break;
- count = cp - path;
- diffcount = count - oldcount + OFFSET;
- oldcount = count;
- if (diffcount < 0 || diffcount > 2 * OFFSET) {
- if (putchar(SWITCH) == EOF ||
- putw(diffcount, stdout) == EOF)
- err(1, "stdout");
- } else
- if (putchar(diffcount) == EOF)
- err(1, "stdout");
- while (*cp != '\0') {
- /* print *two* characters */
- if ((code = BGINDEX(cp)) != (bg_t)-1) {
- /*
- * print *one* as bigram
- * Found, so mark byte with
- * parity bit.
- */
- if (putchar((code / 2) | PARITY) == EOF)
- err(1, "stdout");
- cp += 2;
- }
- else {
- for (i = 0; i < 2; i++) {
- if (*cp == '\0')
- break;
- /* print umlauts in file names */
- if (*cp < ASCII_MIN ||
- *cp > ASCII_MAX) {
- if (putchar(UMLAUT) == EOF ||
- putchar(*cp++) == EOF)
- err(1, "stdout");
- }
- else {
- /* normal character */
- if(putchar(*cp++) == EOF)
- err(1, "stdout");
- }
- }
- }
- }
- if (path == buf1) { /* swap pointers */
- path = buf2;
- oldpath = buf1;
- } else {
- path = buf1;
- oldpath = buf2;
- }
- }
- /* Non-zero status if there were errors */
- if (fflush(stdout) != 0 || ferror(stdout))
- exit(1);
- exit(0);
- }
- #ifndef LOOKUP
- int
- bgindex(char *bg) /* Return location of bg in bigrams or -1. */
- {
- char bg0, bg1, *p;
- bg0 = bg[0];
- bg1 = bg[1];
- for (p = bigrams; *p != NULL; p++)
- if (*p++ == bg0 && *p == bg1)
- break;
- return (*p == NULL ? -1 : (--p - bigrams));
- }
- #endif /* !LOOKUP */
- void
- usage(void)
- {
- (void)fprintf(stderr,
- "usage: locate.code common_bigrams < list > squozen_list\n");
- exit(1);
- }