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
47static 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 */
59void
60uniq(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 */
109static int
110comp(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