sigaltstack.c

/*
 * Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
 * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
 * Copyright (c) 1993-1996 Rick Sladkey <jrs@world.std.com>
 * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
 * Copyright (c) 2005-2015 Dmitry V. Levin <ldv@altlinux.org>
 * Copyright (c) 2015 Elvira Khabirova <lineprinter0@gmail.com>
 * Copyright (c) 2015-2017 The strace developers.
 * 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.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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 "defs.h"

#include DEF_MPERS_TYPE(stack_t)

#include <signal.h>

#include MPERS_DEFS

#include "xlat/sigaltstack_flags.h"

static void
print_stack_t(struct tcb *const tcp, const kernel_ulong_t addr)
{
	stack_t ss;

	if (umove_or_printaddr(tcp, addr, &ss))
		return;

	tprints("{ss_sp=");
	printaddr(ptr_to_kulong(ss.ss_sp));
	tprints(", ss_flags=");
	printflags(sigaltstack_flags, ss.ss_flags, "SS_???");
	tprintf(", ss_size=%" PRI_klu "}", (kernel_ulong_t) ss.ss_size);
}

SYS_FUNC(sigaltstack)
{
	if (entering(tcp)) {
		print_stack_t(tcp, tcp->u_arg[0]);
		tprints(", ");
	} else {
		print_stack_t(tcp, tcp->u_arg[1]);
	}
	return 0;
}