1/*	$NetBSD: conflicts.c,v 1.3 2021/04/10 19:49:59 nia Exp $	*/
2
3/*-
4 * Copyright (c) 2007 Roland Illig <rillig@NetBSD.org>.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in
15 *    the documentation and/or other materials provided with the
16 *    distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
22 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
27 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
28 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32/*
33 * XXX: Reading the +CONTENTS files of all installed packages is
34 * rather slow. Since this check is necessary to avoid conflicting
35 * packages, it should not be removed.
36 *
37 * TODO: Put all the information that is currently in the +CONTENTS
38 * files into one large file or another database.
39 */
40
41#if HAVE_CONFIG_H
42#include "config.h"
43#endif
44
45#include <nbcompat.h>
46
47#if HAVE_SYS_CDEFS_H
48#include <sys/cdefs.h>
49#endif
50
51__RCSID("$NetBSD: conflicts.c,v 1.3 2021/04/10 19:49:59 nia Exp $");
52
53#if HAVE_ERR_H
54#include <err.h>
55#endif
56
57#include "dewey.h"
58#include "lib.h"
59
60/**
61 * Data structure to keep the intermediate result of the conflict
62 * search. ''pkgname'' is the package in question. The first
63 * installed package that conflicts is filled into
64 * ''conflicting_pkgname''. The pattern that leads to the conflict is
65 * also filled in to help the user in deciding what to do with the
66 * conflict.
67 */
68struct package_conflict {
69	const char *pkgname;
70	const char *skip_pkgname;
71	char **conflicting_pkgname;
72	char **conflicting_pattern;
73};
74
75static FILE *
76fopen_contents(const char *pkgname, const char *mode)
77{
78	char *fname;
79	FILE *f;
80
81	fname = pkgdb_pkg_file(pkgname, CONTENTS_FNAME);
82	f = fopen(fname, mode);
83	if (f == NULL) {
84		err(EXIT_FAILURE, "%s", fname);
85		/* NOTREACHED */
86	}
87	free(fname);
88	return f;
89}
90
91
92static int
93check_package_conflict(const char *pkgname, void *v)
94{
95	struct package_conflict *conflict = v;
96	package_t pkg;
97	plist_t *p;
98	FILE *f;
99	int rv;
100
101	if (conflict->skip_pkgname != NULL &&
102	    strcmp(conflict->skip_pkgname, pkgname) == 0)
103		return 0;
104
105	rv = 0;
106
107	f = fopen_contents(pkgname, "r");
108	read_plist(&pkg, f);
109	(void)fclose(f);
110
111	for (p = pkg.head; p; p = p->next) {
112		if (p->type != PLIST_PKGCFL)
113			continue;
114
115		if (pkg_match(p->name, conflict->pkgname) == 1) {
116			*(conflict->conflicting_pkgname) = xstrdup(pkgname);
117			*(conflict->conflicting_pattern) = xstrdup(p->name);
118			rv = 1 /* nonzero, stop iterating */;
119			break;
120		}
121	}
122
123	free_plist(&pkg);
124	return rv;
125}
126
127/**
128 * Checks if some installed package has a pkgcfl entry that matches
129 * PkgName.  If such an entry is found, the package name is returned in
130 * inst_pkgname, the matching pattern in inst_pattern, and the function
131 * returns a non-zero value. Otherwise, zero is returned and the result
132 * variables are set to NULL.
133 */
134int
135some_installed_package_conflicts_with(const char *pkgname,
136    const char *skip_pkgname, char **inst_pkgname, char **inst_pattern)
137{
138	struct package_conflict cfl;
139	int rv;
140
141	cfl.pkgname = pkgname;
142	cfl.skip_pkgname = skip_pkgname;
143	*inst_pkgname = NULL;
144	*inst_pattern = NULL;
145	cfl.conflicting_pkgname = inst_pkgname;
146	cfl.conflicting_pattern = inst_pattern;
147	rv = iterate_pkg_db(check_package_conflict, &cfl);
148	if (rv == -1) {
149		errx(EXIT_FAILURE, "Couldn't read list of installed packages.");
150		/* NOTREACHED */
151	}
152	return *inst_pkgname != NULL;
153}
154
155#if 0
156int main(int argc, char **argv)
157{
158	char *pkg, *patt;
159
160	if (some_installed_package_conflicts_with(argv[1], &pkg, &patt))
161		printf("yes: package %s conflicts with %s, pattern %s\n", pkg, argv[1], patt);
162	else
163		printf("no\n");
164	return 0;
165}
166#endif
167