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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <stdint.h>
#include <stdlib.h>
#include <strings.h>
int
baz(void)
{
return (8);
}
static int
foo(void)
{
/*
* In order to assure that our helper is properly employed to identify
* the frame, we're going to trampoline through data.
*/
uint8_t instr[] = {
0x55, /* pushl %ebp */
0x8b, 0xec, /* movl %esp, %ebp */
0xe8, 0x0, 0x0, 0x0, 0x0, /* call baz */
0x8b, 0xe5, /* movl %ebp, %esp */
0x5d, /* popl %ebp */
0xc3 /* ret */
};
uint8_t *fp = malloc(sizeof (instr));
/*
* Do our little relocation dance.
*/
*((int *)&instr[4]) = (uintptr_t)baz - (uintptr_t)&fp[8];
/*
* Copy the code to the heap (it's a pain to build in ON with an
* executable stack).
*/
bcopy(instr, fp, sizeof (instr));
(*(int (*)(void))fp)();
free(fp);
return (0);
}
int
main(int argc, char **argv)
{
for (;;) {
foo();
}
return (0);
}
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