/* Save current context. Copyright (C) 2002-2012 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Andreas Jaeger , 2002. 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 . */ #include #include "ucontext_i.h" /* int __getcontext (ucontext_t *ucp) Saves the machine context in UCP such that when it is activated, it appears as if __getcontext() returned again. This implementation is intended to be used for *synchronous* context switches only. Therefore, it does not have to save anything other than the PRESERVED state. */ ENTRY(__getcontext) /* Save the preserved registers, the registers used for passing args, and the return address. */ movq %rbx, oRBX(%rdi) movq %rbp, oRBP(%rdi) movq %r12, oR12(%rdi) movq %r13, oR13(%rdi) movq %r14, oR14(%rdi) movq %r15, oR15(%rdi) movq %rdi, oRDI(%rdi) movq %rsi, oRSI(%rdi) movq %rdx, oRDX(%rdi) movq %rcx, oRCX(%rdi) movq %r8, oR8(%rdi) movq %r9, oR9(%rdi) movq (%rsp), %rcx movq %rcx, oRIP(%rdi) leaq 8(%rsp), %rcx /* Exclude the return address. */ movq %rcx, oRSP(%rdi) /* 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. */ leaq oFPREGSMEM(%rdi), %rcx movq %rcx, oFPREGS(%rdi) /* Save the floating-point environment. */ fnstenv (%rcx) fldenv (%rcx) stmxcsr oMXCSR(%rdi) /* Save the current signal mask with rt_sigprocmask (SIG_BLOCK, NULL, set,_NSIG/8). */ leaq oSIGMASK(%rdi), %rdx xorl %esi,%esi #if SIG_BLOCK == 0 xorl %edi, %edi #else movl $SIG_BLOCK, %edi #endif movl $_NSIG8,%r10d movl $__NR_rt_sigprocmask, %eax syscall cmpq $-4095, %rax /* Check %rax 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)