xref: /freebsd/usr.sbin/services_mkdb/uniq.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*	$NetBSD: uniq.c,v 1.4 2008/04/28 20:24:17 martin 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 __FBSDID("$FreeBSD$");
33 
34 #include <stdio.h>
35 #include <string.h>
36 #include <stdlib.h>
37 #include <db.h>
38 #include <err.h>
39 #include <libutil.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 	if ((fp = fopen(fname, "r")) == NULL)
72 		err(1, "Cannot open `%s'", fname);
73 	while ((line = fgetln(fp, &len)) != NULL) {
74 		size_t complen = len;
75 		char *compline;
76 		if (!comp(line, &compline, &complen)) {
77 			(void)fprintf(stdout, "%*.*s", (int)len, (int)len,
78 			    line);
79 			continue;
80 		}
81 		key.data = compline;
82 		key.size = complen;
83 		switch ((db->put)(db, &key, &data, R_NOOVERWRITE)) {
84 		case 0:
85 			(void)fprintf(stdout, "%*.*s", (int)len, (int)len,
86 			    line);
87 			break;
88 		case 1:
89 			break;
90 		case -1:
91 			err(1, "put");
92 		default:
93 			abort();
94 			break;
95 		}
96 	}
97 	(void)fflush(stdout);
98 	exit(0);
99 }
100 
101 /*
102  * normalize whitespace in the original line and place a new string
103  * with whitespace converted to a single space in compline. If the line
104  * contains just comments, we preserve them. If it contains data and
105  * comments, we kill the comments. Return 1 if the line had actual
106  * contents, or 0 if it was just a comment without alphanumeric characters.
107  */
108 static int
109 comp(const char *origline, char **compline, size_t *len)
110 {
111 	const unsigned char *p;
112 	unsigned char *q;
113 	char *cline;
114 	size_t l = *len, complen;
115 	int hasalnum, iscomment;
116 
117 	/* Eat leading space */
118 	for (p = (const unsigned char *)origline; l && *p && isspace(*p);
119 	    p++, l--)
120 		continue;
121 	if ((cline = malloc(l + 1)) == NULL)
122 		err(1, "Cannot allocate %zu bytes", l + 1);
123 	(void)memcpy(cline, p, l);
124 	cline[l] = '\0';
125 	if (*cline == '\0')
126 		return 0;
127 
128 	complen = 0;
129 	hasalnum = 0;
130 	iscomment = 0;
131 
132 	for (q = (unsigned char *)cline; l && *p; p++, l--) {
133 		if (isspace(*p)) {
134 			if (complen && isspace(q[-1]))
135 				continue;
136 			*q++ = ' ';
137 			complen++;
138 		} else {
139 			if (!iscomment && *p == '#') {
140 				if (hasalnum)
141 					break;
142 				iscomment = 1;
143 			} else
144 				hasalnum |= isalnum(*p);
145 			*q++ = *p;
146 			complen++;
147 		}
148 	}
149 
150 	/* Eat trailing space */
151 	while (complen && isspace(q[-1])) {
152 		--q;
153 		--complen;
154 	}
155 	*q = '\0';
156 	*compline = cline;
157 	*len = complen;
158 	return hasalnum;
159 }
160