1  /* __libc_siglongjmp for x86.
       2     Copyright (C) 2018-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       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.
       9  
      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.
      14  
      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/>.  */
      18  
      19  #define __libc_longjmp __redirect___libc_longjmp
      20  #include <setjmp/longjmp.c>
      21  #undef __libc_longjmp
      22  
      23  extern void __longjmp_cancel (__jmp_buf __env, int __val)
      24       __attribute__ ((__noreturn__)) attribute_hidden;
      25  
      26  /* Since __libc_longjmp is a private interface for cancellation
      27     implementation in libpthread, there is no need to restore shadow
      28     stack register.  */
      29  
      30  void
      31  __libc_longjmp (sigjmp_buf env, int val)
      32  {
      33    /* Perform any cleanups needed by the frames being unwound.  */
      34    _longjmp_unwind (env, val);
      35  
      36    if (env[0].__mask_was_saved)
      37      /* Restore the saved signal mask.  */
      38      (void) __sigprocmask (SIG_SETMASK,
      39  			  (sigset_t *) &env[0].__saved_mask,
      40  			  (sigset_t *) NULL);
      41  
      42    /* Call the machine-dependent function to restore machine state
      43       without shadow stack.  */
      44    __longjmp_cancel (env[0].__jmpbuf, val ?: 1);
      45  }