xref: /freebsd/usr.sbin/services_mkdb/uniq.c (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
1 /*	$NetBSD: uniq.c,v 1.4 2008/04/28 20:24:17 martin Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-2-Clause-NetBSD
5  *
6  * Copyright (c) 2007 The NetBSD Foundation, Inc.
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Christos Zoulas.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <stdio.h>
37 #include <string.h>
38 #include <stdlib.h>
39 #include <db.h>
40 #include <err.h>
41 #include <libutil.h>
42 #include <ctype.h>
43 #include <fcntl.h>
44 
45 #include "extern.h"
46 
47 static int comp(const char *, char **, size_t *);
48 
49 /*
50  * Preserve only unique content lines in a file. Input lines that have
51  * content [alphanumeric characters before a comment] are white-space
52  * normalized and have their comments removed. Then they are placed
53  * in a hash table, and only the first instance of them is printed.
54  * Comment lines without any alphanumeric content are always printed
55  * since they are there to make the file "pretty". Comment lines with
56  * alphanumeric content are also placed into the hash table and only
57  * printed once.
58  */
59 void
60 uniq(const char *fname)
61 {
62 	DB *db;
63 	DBT key;
64 	static const DBT data = { NULL, 0 };
65 	FILE *fp;
66 	char *line;
67 	size_t len;
68 
69 	if ((db = dbopen(NULL, O_RDWR, 0, DB_HASH, &hinfo)) == NULL)
70 		err(1, "Cannot create in memory database");
71 
72 	if ((fp = fopen(fname, "r")) == NULL)
73 		err(1, "Cannot open `%s'", fname);
74 	while ((line = fgetln(fp, &len)) != NULL) {
75 		size_t complen = len;
76 		char *compline;
77 		if (!comp(line, &compline, &complen)) {
78 			(void)fprintf(stdout, "%*.*s", (int)len, (int)len,
79 			    line);
80 			continue;
81 		}
82 		key.data = compline;
83 		key.size = complen;
84 		switch ((db->put)(db, &key, &data, R_NOOVERWRITE)) {
85 		case 0:
86 			(void)fprintf(stdout, "%*.*s", (int)len, (int)len,
87 			    line);
88 			break;
89 		case 1:
90 			break;
91 		case -1:
92 			err(1, "put");
93 		default:
94 			abort();
95 			break;
96 		}
97 	}
98 	(void)fflush(stdout);
99 	exit(0);
100 }
101 
102 /*
103  * normalize whitespace in the original line and place a new string
104  * with whitespace converted to a single space in compline. If the line
105  * contains just comments, we preserve them. If it contains data and
106  * comments, we kill the comments. Return 1 if the line had actual
107  * contents, or 0 if it was just a comment without alphanumeric characters.
108  */
109 static int
110 comp(const char *origline, char **compline, size_t *len)
111 {
112 	const unsigned char *p;
113 	unsigned char *q;
114 	char *cline;
115 	size_t l = *len, complen;
116 	int hasalnum, iscomment;
117 
118 	/* Eat leading space */
119 	for (p = (const unsigned char *)origline; l && *p && isspace(*p);
120 	    p++, l--)
121 		continue;
122 	if ((cline = malloc(l + 1)) == NULL)
123 		err(1, "Cannot allocate %zu bytes", l + 1);
124 	(void)memcpy(cline, p, l);
125 	cline[l] = '\0';
126 	if (*cline == '\0')
127 		return 0;
128 
129 	complen = 0;
130 	hasalnum = 0;
131 	iscomment = 0;
132 
133 	for (q = (unsigned char *)cline; l && *p; p++, l--) {
134 		if (isspace(*p)) {
135 			if (complen && isspace(q[-1]))
136 				continue;
137 			*q++ = ' ';
138 			complen++;
139 		} else {
140 			if (!iscomment && *p == '#') {
141 				if (hasalnum)
142 					break;
143 				iscomment = 1;
144 			} else
145 				hasalnum |= isalnum(*p);
146 			*q++ = *p;
147 			complen++;
148 		}
149 	}
150 
151 	/* Eat trailing space */
152 	while (complen && isspace(q[-1])) {
153 		--q;
154 		--complen;
155 	}
156 	*q = '\0';
157 	*compline = cline;
158 	*len = complen;
159 	return hasalnum;
160 }
161