usr.sbin/services_mkdb/uniq.c

   1 /*      $NetBSD: uniq.c,v 1.3 2007/06/24 19:51:43 christos Exp $        */
   2
   3 /*-
   4  * Copyright (c) 2007 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Christos Zoulas.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31 #include <sys/cdefs.h>
  32 __RCSID("$NetBSD: uniq.c,v 1.3 2007/06/24 19:51:43 christos Exp $");
  33
  34 #include <stdio.h>
  35 #include <string.h>
  36 #include <stdlib.h>
  37 #include <db.h>
  38 #include <err.h>
  39 #include <util.h>
  40 #include <ctype.h>
  41 #include <fcntl.h>
  42
  43 extern const HASHINFO hinfo;
  44
  45 void uniq(const char *);
  46 static int comp(const char *, char **, size_t *);
  47
  48 /*
  49  * Preserve only unique content lines in a file. Input lines that have
  50  * content [alphanumeric characters before a comment] are white-space
  51  * normalized and have their comments removed. Then they are placed
  52  * in a hash table, and only the first instance of them is printed.
  53  * Comment lines without any alphanumeric content are always printed
  54  * since they are there to make the file "pretty". Comment lines with
  55  * alphanumeric content are also placed into the hash table and only
  56  * printed once.
  57  */
  58 void
  59 uniq(const char *fname)
  60 {
  61         DB *db;
  62         DBT key;
  63         static const DBT data = { NULL, 0 };
  64         FILE *fp;
  65         char *line;
  66         size_t len;
  67
  68         if ((db = dbopen(NULL, O_RDWR, 0, DB_HASH, &hinfo)) == NULL)
  69                 err(1, "Cannot create in memory database");
  70
  71         fp = efopen(fname, "r");
  72         while ((line = fgetln(fp, &len)) != NULL) {
  73                 size_t complen = len;
  74                 char *compline;
  75                 if (!comp(line, &compline, &complen)) {
  76                         (void)fprintf(stdout, "%*.*s", (int)len, (int)len,
  77                             line);
  78                         continue;
  79                 }
  80                 key.data = compline;
  81                 key.size = complen;
  82                 switch ((db->put)(db, &key, &data, R_NOOVERWRITE)) {
  83                 case 0:
  84                         (void)fprintf(stdout, "%*.*s", (int)len, (int)len,
  85                             line);
  86                         break;
  87                 case 1:
  88                         break;
  89                 case -1:
  90                         err(1, "put");
  91                 default:
  92                         abort();
  93                         break;
  94                 }
  95         }
  96         (void)fflush(stdout);
  97         exit(0);
  98 }
  99
 100 /*
 101  * normalize whitespace in the original line and place a new string
 102  * with whitespace converted to a single space in compline. If the line
 103  * contains just comments, we preserve them. If it contains data and
 104  * comments, we kill the comments. Return 1 if the line had actual
 105  * contents, or 0 if it was just a comment without alphanumeric characters.
 106  */
 107 static int
 108 comp(const char *origline, char **compline, size_t *len)
 109 {
 110         const unsigned char *p;
 111         unsigned char *q;
 112         char *cline;
 113         size_t l = *len, complen;
 114         int hasalnum, iscomment;
 115
 116         /* Eat leading space */
 117         for (p = (const unsigned char *)origline; l && *p && isspace(*p);
 118             p++, l--)
 119                 continue;
 120         cline = emalloc(l + 1);
 121         (void)memcpy(cline, p, l);
 122         cline[l] = '\0';
 123         if (*cline == '\0')
 124                 return 0;
 125
 126         complen = 0;
 127         hasalnum = 0;
 128         iscomment = 0;
 129
 130         for (q = (unsigned char *)cline; l && *p; p++, l--) {
 131                 if (isspace(*p)) {
 132                         if (complen && isspace(q[-1]))
 133                                 continue;
 134                         *q++ = ' ';
 135                         complen++;
 136                 } else {
 137                         if (!iscomment && *p == '#') {
 138                                 if (hasalnum)
 139                                         break;
 140                                 iscomment = 1;
 141                         } else
 142                                 hasalnum |= isalnum(*p);
 143                         *q++ = *p;
 144                         complen++;
 145                 }
 146         }
 147
 148         /* Eat trailing space */
 149         while (complen && isspace(q[-1])) {
 150                 --q;
 151                 --complen;
 152         }
 153         *q = '\0';
 154         *compline = cline;
 155         *len = complen;
 156         return hasalnum;
 157 }