usr.sbin/services_mkdb/uniq.c

   1 /*      $NetBSD: uniq.c,v 1.6 2014/06/21 17:48:07 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 1.6 2014/06/21 17:48:07 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 #include "extern.h"
  44
  45 static const HASHINFO hinfo = {
  46         .bsize = 256,
  47         .ffactor = 4,
  48         .nelem = 32768,
  49         .cachesize = 1024,
  50         .hash = NULL,
  51         .lorder = 0
  52 };
  53
  54 static int comp(const char *, char **, size_t *);
  55
  56 /*
  57  * Preserve only unique content lines in a file. Input lines that have
  58  * content [alphanumeric characters before a comment] are white-space
  59  * normalized and have their comments removed. Then they are placed
  60  * in a hash table, and only the first instance of them is printed.
  61  * Comment lines without any alphanumeric content are always printed
  62  * since they are there to make the file "pretty". Comment lines with
  63  * alphanumeric content are also placed into the hash table and only
  64  * printed once.
  65  */
  66 void
  67 uniq(const char *fname)
  68 {
  69         DB *db;
  70         DBT key;
  71         static const DBT data = { NULL, 0 };
  72         FILE *fp;
  73         char *line;
  74         size_t len;
  75
  76         if ((db = dbopen(NULL, O_RDWR, 0, DB_HASH, &hinfo)) == NULL)
  77                 err(1, "Cannot create in memory database");
  78
  79         fp = efopen(fname, "r");
  80         while ((line = fgetln(fp, &len)) != NULL) {
  81                 size_t complen = len;
  82                 char *compline;
  83                 if (!comp(line, &compline, &complen)) {
  84                         (void)fprintf(stdout, "%*.*s", (int)len, (int)len,
  85                             line);
  86                         continue;
  87                 }
  88                 key.data = compline;
  89                 key.size = complen;
  90                 switch ((db->put)(db, &key, &data, R_NOOVERWRITE)) {
  91                 case 0:
  92                         (void)fprintf(stdout, "%*.*s", (int)len, (int)len,
  93                             line);
  94                         break;
  95                 case 1:
  96                         break;
  97                 case -1:
  98                         err(1, "put");
  99                         /*NOTREACHED*/
 100                 default:
 101                         abort();
 102                         break;
 103                 }
 104         }
 105         (void)fflush(stdout);
 106         exit(0);
 107 }
 108
 109 /*
 110  * normalize whitespace in the original line and place a new string
 111  * with whitespace converted to a single space in compline. If the line
 112  * contains just comments, we preserve them. If it contains data and
 113  * comments, we kill the comments. Return 1 if the line had actual
 114  * contents, or 0 if it was just a comment without alphanumeric characters.
 115  */
 116 static int
 117 comp(const char *origline, char **compline, size_t *len)
 118 {
 119         const unsigned char *p;
 120         unsigned char *q;
 121         char *cline;
 122         size_t l = *len, complen;
 123         int hasalnum, iscomment;
 124
 125         /* Eat leading space */
 126         for (p = (const unsigned char *)origline; l && *p && isspace(*p);
 127             p++, l--)
 128                 continue;
 129         cline = emalloc(l + 1);
 130         (void)memcpy(cline, p, l);
 131         cline[l] = '\0';
 132         if (*cline == '\0')
 133                 return 0;
 134
 135         complen = 0;
 136         hasalnum = 0;
 137         iscomment = 0;
 138
 139         for (q = (unsigned char *)cline; l && *p; p++, l--) {
 140                 if (isspace(*p)) {
 141                         if (complen && isspace(q[-1]))
 142                                 continue;
 143                         *q++ = ' ';
 144                         complen++;
 145                 } else {
 146                         if (!iscomment && *p == '#') {
 147                                 if (hasalnum)
 148                                         break;
 149                                 iscomment = 1;
 150                         } else
 151                                 hasalnum |= isalnum(*p);
 152                         *q++ = *p;
 153                         complen++;
 154                 }
 155         }
 156
 157         /* Eat trailing space */
 158         while (complen && isspace(q[-1])) {
 159                 --q;
 160                 --complen;
 161         }
 162         *q = '\0';
 163         *compline = cline;
 164         *len = complen;
 165         return hasalnum;
 166 }