xref: /freebsd/usr.sbin/services_mkdb/uniq.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1 /*	$NetBSD: uniq.c,v 1.4 2008/04/28 20:24:17 martin Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-2-Clause
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 #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 #include "extern.h"
44 
45 static int comp(const char *, char **, size_t *);
46 
47 /*
48  * Preserve only unique content lines in a file. Input lines that have
49  * content [alphanumeric characters before a comment] are white-space
50  * normalized and have their comments removed. Then they are placed
51  * in a hash table, and only the first instance of them is printed.
52  * Comment lines without any alphanumeric content are always printed
53  * since they are there to make the file "pretty". Comment lines with
54  * alphanumeric content are also placed into the hash table and only
55  * printed once.
56  */
57 void
58 uniq(const char *fname)
59 {
60 	DB *db;
61 	DBT key;
62 	static const DBT data = { NULL, 0 };
63 	FILE *fp;
64 	char *line;
65 	size_t len;
66 
67 	if ((db = dbopen(NULL, O_RDWR, 0, DB_HASH, &hinfo)) == NULL)
68 		err(1, "Cannot create in memory database");
69 
70 	if ((fp = fopen(fname, "r")) == NULL)
71 		err(1, "Cannot open `%s'", fname);
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 			/* NOTREACHED */
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 (*p == '\0' || l == 0)
122 		return 0;
123 
124 	if ((cline = malloc(l + 1)) == NULL)
125 		err(1, "Cannot allocate %zu bytes", l + 1);
126 	(void)memcpy(cline, p, l);
127 	cline[l] = '\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 	if (!hasalnum) {
158 		free(cline);
159 		cline = NULL;
160 		complen = 0;
161 	}
162 	*compline = cline;
163 	*len = complen;
164 	return hasalnum;
165 }
166