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/* Install given context.
Copyright (C) 2001 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2001.
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 <sysdep.h>
#include "ucontext_i.h"
ENTRY(__setcontext)
/* Load address of the context data structure. */
movl 4(%esp), %eax
/* Get the current signal mask. Note that we preserve EBX in case
the system call fails and we return from the function with an
error. */
pushl %ebx
xorl %edx, %edx
leal oSIGMASK(%eax), %ecx
movl $SIG_SETMASK, %ebx
movl $__NR_sigprocmask, %eax
int $0x80
popl %ebx
cmpl $-4095, %eax /* Check %eax for error. */
jae SYSCALL_ERROR_LABEL /* Jump to error handler if error. */
/* EAX was modified, reload it. */
movl 4(%esp), %eax
/* Restore the floating-point context. Not the registers, only the
rest. */
movl oFPREGS(%eax), %ecx
fldenv (%ecx)
/* Restore the FS segment register. We don't touch the GS register
since it is used for threads. */
movl oFS(%eax), %ecx
movw %cx, %fs
/* Load the new stack pointer. */
movl oESP(%eax), %ecx
/* Make room for 8 registers and the return address. We will load
the values from the stack. */
subl $36, %ecx
/* Move the values of all the 32-bit registers (except ESP) on
the stack. This happens in the form the 'popa' instruction
expects it. Before this block put the address of the code
to execute. */
movl oEDI(%eax), %ebx
movl oESI(%eax), %edx
movl oEBP(%eax), %esi
movl oEBX(%eax), %edi
movl %ebx, (%ecx)
movl %edx, 4(%ecx)
movl %esi, 8(%ecx)
movl %edi, 16(%ecx)
movl oEDX(%eax), %ebx
movl oECX(%eax), %edx
movl oEAX(%eax), %esi
movl oEIP(%eax), %edi
movl %ebx, 20(%ecx)
movl %edx, 24(%ecx)
movl %esi, 28(%ecx)
movl %edi, 32(%ecx)
/* Set the new stack address. The stack points now to the block
we put the register content in. */
movl %ecx, %esp
/* Restore the register content. */
popa
/* The following 'ret' will pop the addres of the code and jump
to it. */
L(pseudo_end):
ret
PSEUDO_END(__setcontext)
weak_alias(__setcontext, setcontext)
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