freebsd-dev/lib/libarchive/archive_check_magic.c
2007-04-02 00:15:45 +00:00

119 lines
3.2 KiB
C

/*-
* Copyright (c) 2003-2007 Tim Kientzle
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "archive_platform.h"
__FBSDID("$FreeBSD$");
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "archive_private.h"
static void
errmsg(const char *m)
{
write(STDERR_FILENO, m, strlen(m));
}
static void
diediedie(void)
{
*(char *)0 = 1; /* Deliberately segfault and force a coredump. */
_exit(1); /* If that didn't work, just exit with an error. */
}
static const char *
state_name(unsigned s)
{
switch (s) {
case ARCHIVE_STATE_NEW: return ("new");
case ARCHIVE_STATE_HEADER: return ("header");
case ARCHIVE_STATE_DATA: return ("data");
case ARCHIVE_STATE_EOF: return ("eof");
case ARCHIVE_STATE_CLOSED: return ("closed");
case ARCHIVE_STATE_FATAL: return ("fatal");
default: return ("??");
}
}
static void
write_all_states(unsigned int states)
{
unsigned int lowbit;
/* A trick for computing the lowest set bit. */
while ((lowbit = states & (-states)) != 0) {
states &= ~lowbit; /* Clear the low bit. */
errmsg(state_name(lowbit));
if (states != 0)
errmsg("/");
}
}
/*
* Check magic value and current state; bail if it isn't valid.
*
* This is designed to catch serious programming errors that violate
* the libarchive API.
*/
void
__archive_check_magic(struct archive *a, unsigned int magic,
unsigned int state, const char *function)
{
if (a->magic != magic) {
errmsg("INTERNAL ERROR: Function ");
errmsg(function);
errmsg(" invoked with invalid struct archive structure.\n");
diediedie();
}
if (state == ARCHIVE_STATE_ANY)
return;
if ((a->state & state) == 0) {
errmsg("INTERNAL ERROR: Function '");
errmsg(function);
errmsg("' invoked with archive structure in state '");
write_all_states(a->state);
errmsg("', should be in state '");
write_all_states(state);
errmsg("'\n");
diediedie();
}
}