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/* Copyright (C) 2008 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by David Bartley <dtbartle@csclub.uwaterloo.ca>, 2008.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <sys/types.h>
#include <sys/regset.h>
#include <sys/stack.h>
#include <ucontext.h>
#include <stdarg.h>
#include <assert.h>
void
__restorecontext (void)
{
ucontext_t uc;
assert (getcontext (&uc) == 0);
assert (setcontext (uc.uc_link) == 0);
}
void
makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...)
{
/* setup the stack (note that it grows down) */
void *stack_addr = ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size -
(argc + 1) * sizeof(uint32_t);
uint32_t *stack_ptr = (uint32_t *)((uint32_t)stack_addr &
~(STACK_ALIGN - 1));
ucp->uc_mcontext.gregs[UESP] = (greg_t)stack_ptr;
*stack_ptr++ = (uint32_t)__restorecontext; /* return addr */
va_list ap;
va_start (ap, argc);
while (argc--)
*stack_ptr++ = (uint32_t)va_arg (ap, char *); /* arg */
ucp->uc_mcontext.gregs[EIP] = (greg_t)func;
}
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