sysdeps/unix/sysv/linux/loongarch/vfork.S

   1 /* vfork for Linux.
   2    Copyright (C) 2022-2023 Free Software Foundation, Inc.
   3
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public License as
   8    published by the Free Software Foundation; either version 2.1 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <https://www.gnu.org/licenses/>.  */
  19
  20 #include <sysdep.h>
  21 #define _ERRNO_H  1
  22 #include <bits/errno.h>
  23
  24 /* Clone the calling process, but without copying the whole address space.
  25    The calling process is suspended until the new process exits or is
  26    replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,
  27    and the process ID of the new process to the old process.  */
  28
  29 ENTRY (__vfork)
  30
  31         li.d    a0, 0x4111 /* CLONE_VM | CLONE_VFORK | SIGCHLD */
  32         add.d   a1, zero, sp
  33
  34         /* Do the system call.  */
  35         li.d    a7, __NR_clone
  36         syscall 0
  37
  38         blt     a0, zero ,L (error)
  39
  40         ret
  41
  42 L (error):
  43         b       __syscall_error
  44
  45 END (__vfork)
  46
  47 libc_hidden_def (__vfork)
  48
  49 weak_alias (__vfork, vfork)
  50 strong_alias (__vfork, __libc_vfork)