1/*-
2 * Copyright (c) 2003-2010 Tim Kientzle
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "archive_platform.h"
27
28#ifdef HAVE_SYS_TYPES_H
29#include <sys/types.h>
30#endif
31
32#include <stdio.h>
33#ifdef HAVE_STDLIB_H
34#include <stdlib.h>
35#endif
36#ifdef HAVE_STRING_H
37#include <string.h>
38#endif
39#ifdef HAVE_UNISTD_H
40#include <unistd.h>
41#endif
42#if defined(_WIN32) && !defined(__CYGWIN__)
43#include <windows.h>
44#include <winbase.h>
45#endif
46
47#include "archive_private.h"
48
49static void
50errmsg(const char *m)
51{
52	size_t s = strlen(m);
53	ssize_t written;
54
55	while (s > 0) {
56		written = write(2, m, s);
57		if (written <= 0)
58			return;
59		m += written;
60		s -= written;
61	}
62}
63
64static __LA_NORETURN void
65diediedie(void)
66{
67#if defined(_WIN32) && !defined(__CYGWIN__) && defined(_DEBUG)
68	/* Cause a breakpoint exception  */
69	DebugBreak();
70#endif
71	abort();        /* Terminate the program abnormally. */
72}
73
74static const char *
75state_name(unsigned s)
76{
77	switch (s) {
78	case ARCHIVE_STATE_NEW:		return ("new");
79	case ARCHIVE_STATE_HEADER:	return ("header");
80	case ARCHIVE_STATE_DATA:	return ("data");
81	case ARCHIVE_STATE_EOF:		return ("eof");
82	case ARCHIVE_STATE_CLOSED:	return ("closed");
83	case ARCHIVE_STATE_FATAL:	return ("fatal");
84	default:			return ("??");
85	}
86}
87
88static const char *
89archive_handle_type_name(unsigned m)
90{
91	switch (m) {
92	case ARCHIVE_WRITE_MAGIC:	return ("archive_write");
93	case ARCHIVE_READ_MAGIC:	return ("archive_read");
94	case ARCHIVE_WRITE_DISK_MAGIC:	return ("archive_write_disk");
95	case ARCHIVE_READ_DISK_MAGIC:	return ("archive_read_disk");
96	case ARCHIVE_MATCH_MAGIC:	return ("archive_match");
97	default:			return NULL;
98	}
99}
100
101static void
102write_all_states(char *buff, unsigned int states)
103{
104	unsigned int lowbit;
105
106	*buff = '\0';
107
108	/* A trick for computing the lowest set bit. */
109	while ((lowbit = states & (1 + ~states)) != 0) {
110		states &= ~lowbit;		/* Clear the low bit. */
111		strcat(buff, state_name(lowbit));
112		if (states != 0)
113			strcat(buff, "/");
114	}
115}
116
117/*
118 * Check magic value and current state.
119 *   Magic value mismatches are fatal and result in calls to abort().
120 *   State mismatches return ARCHIVE_FATAL.
121 *   Otherwise, returns ARCHIVE_OK.
122 *
123 * This is designed to catch serious programming errors that violate
124 * the libarchive API.
125 */
126int
127__archive_check_magic(struct archive *a, unsigned int magic,
128    unsigned int state, const char *function)
129{
130	char states1[64];
131	char states2[64];
132	const char *handle_type;
133
134	/*
135	 * If this isn't some form of archive handle,
136	 * then the library user has screwed up so bad that
137	 * we don't even have a reliable way to report an error.
138	 */
139	handle_type = archive_handle_type_name(a->magic);
140
141	if (!handle_type) {
142		errmsg("PROGRAMMER ERROR: Function ");
143		errmsg(function);
144		errmsg(" invoked with invalid archive handle.\n");
145		diediedie();
146	}
147
148	if (a->magic != magic) {
149		archive_set_error(a, -1,
150		    "PROGRAMMER ERROR: Function '%s' invoked"
151		    " on '%s' archive object, which is not supported.",
152		    function,
153		    handle_type);
154		a->state = ARCHIVE_STATE_FATAL;
155		return (ARCHIVE_FATAL);
156	}
157
158	if ((a->state & state) == 0) {
159		/* If we're already FATAL, don't overwrite the error. */
160		if (a->state != ARCHIVE_STATE_FATAL) {
161			write_all_states(states1, a->state);
162			write_all_states(states2, state);
163			archive_set_error(a, -1,
164			    "INTERNAL ERROR: Function '%s' invoked with"
165			    " archive structure in state '%s',"
166			    " should be in state '%s'",
167			    function,
168			    states1,
169			    states2);
170		}
171		a->state = ARCHIVE_STATE_FATAL;
172		return (ARCHIVE_FATAL);
173	}
174	return (ARCHIVE_OK);
175}
176