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-rw-r--r-- | sysdeps/unix/sysv/linux/i386/getcontext.S | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/getcontext.S b/sysdeps/unix/sysv/linux/i386/getcontext.S new file mode 100644 index 0000000000..c4dddba30c --- /dev/null +++ b/sysdeps/unix/sysv/linux/i386/getcontext.S @@ -0,0 +1,79 @@ +/* Save current 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 Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. 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(__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 and GS segment register. */ + xorl %edx, %edx + xorl %ecx, %ecx + movw %gs, %dx + movw %fs, %cx + movl %edx, oGS(%eax) + movl %ecx, 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) + + /* Save the current signal mask. */ + pushl %ebx + leal oSIGMASK(%eax), %edx + xorl %ecx, %ecx + movl $SIG_BLOCK, %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. */ + + /* All done, return 0 for success. */ + xorl %eax, %eax +L(pseudo_end): + ret +PSEUDO_END(__getcontext) + +weak_alias(__getcontext, getcontext) |