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- /* Save current context.
- Copyright (C) 2001-2012 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, see
- <http://www.gnu.org/licenses/>. */
- #include <sysdep.h>
- #include "ucontext_i.h"
- ENTRY(__getcontext)
- /* Load address of the context data structure. */
- movl 4(%esp), %eax
- /* Return value of getcontext. EAX is the only register whose
- value is not preserved. */
- movl $0, oEAX(%eax)
- /* Save the 32-bit register values and the return address. */
- movl %ecx, oECX(%eax)
- movl %edx, oEDX(%eax)
- movl %edi, oEDI(%eax)
- movl %esi, oESI(%eax)
- movl %ebp, oEBP(%eax)
- movl (%esp), %ecx
- movl %ecx, oEIP(%eax)
- leal 4(%esp), %ecx /* Exclude the return address. */
- movl %ecx, oESP(%eax)
- movl %ebx, oEBX(%eax)
- /* Save the FS segment register. We don't touch the GS register
- since it is used for threads. */
- xorl %edx, %edx
- movw %fs, %dx
- movl %edx, oFS(%eax)
- /* We have separate floating-point register content memory on the
- stack. We use the __fpregs_mem block in the context. Set the
- links up correctly. */
- leal oFPREGSMEM(%eax), %ecx
- movl %ecx, oFPREGS(%eax)
- /* Save the floating-point context. */
- fnstenv (%ecx)
- /* And load it right back since the processor changes the mask.
- Intel thought this opcode to be used in interrupt handlers which
- would block all exceptions. */
- fldenv (%ecx)
- /* Save the current signal mask. */
- pushl %ebx
- cfi_adjust_cfa_offset (4)
- cfi_rel_offset (ebx, 0)
- leal oSIGMASK(%eax), %edx
- xorl %ecx, %ecx
- movl $SIG_BLOCK, %ebx
- movl $__NR_sigprocmask, %eax
- ENTER_KERNEL
- popl %ebx
- cfi_adjust_cfa_offset (-4)
- cfi_restore (ebx)
- cmpl $-4095, %eax /* Check %eax for error. */
- jae SYSCALL_ERROR_LABEL /* Jump to error handler if error. */
- /* All done, return 0 for success. */
- xorl %eax, %eax
- L(pseudo_end):
- ret
- PSEUDO_END(__getcontext)
- weak_alias (__getcontext, getcontext)
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