1 /* Save current context.
2 Copyright (C) 2001-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
21 #include "ucontext_i.h"
25 /* Load address of the context data structure. */
28 /* Save the preserved register values and the return address. */
34 leal 4(%esp), %ecx /* Exclude the return address. */
38 /* Save the FS segment register. We don't touch the GS register
39 since it is used for threads. */
44 /* We have separate floating-point register content memory on the
45 stack. We use the __fpregs_mem block in the context. Set the
46 links up correctly. */
47 leal oFPREGSMEM(%eax), %ecx
48 movl %ecx, oFPREGS(%eax)
49 /* Save the floating-point context. */
51 /* And load it right back since the processor changes the mask.
52 Intel thought this opcode to be used in interrupt handlers which
53 would block all exceptions. */
56 /* Save the current signal mask. */
58 cfi_adjust_cfa_offset (4)
59 cfi_rel_offset (ebx, 0)
60 leal oSIGMASK(%eax), %edx
63 movl $__NR_sigprocmask, %eax
66 cfi_adjust_cfa_offset (-4)
68 cmpl $-4095, %eax /* Check %eax for error. */
69 jae SYSCALL_ERROR_LABEL /* Jump to error handler if error. */
71 /* All done, return 0 for success. */
74 PSEUDO_END(__getcontext)
76 weak_alias (__getcontext, getcontext)