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- /* arch_fork definition for Linux fork implementation.
- Copyright (C) 2014-2019 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- 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
- <http://www.gnu.org/licenses/>. */
- #ifndef __ARCH_FORK_H
- #define __ARCH_FORK_H
- #include <unistd.h>
- /* Call the clone syscall with fork semantic. The CTID address is used
- to store the child thread ID at its locationm, to erase it in child memory
- when the child exits, and do a wakeup on the futex at that address.
- The architecture with non-default kernel abi semantic should correctlly
- override it with one of the supported calling convention (check generic
- kernel-features.h for the clone abi variants). */
- static inline pid_t
- arch_fork (void *ctid)
- {
- const int flags = CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID | SIGCHLD;
- long int ret;
- #ifdef __ASSUME_CLONE_BACKWARDS
- # ifdef INLINE_CLONE_SYSCALL
- ret = INLINE_CLONE_SYSCALL (flags, 0, NULL, 0, ctid);
- # else
- ret = INLINE_SYSCALL_CALL (clone, flags, 0, NULL, 0, ctid);
- # endif
- #elif defined(__ASSUME_CLONE_BACKWARDS2)
- ret = INLINE_SYSCALL_CALL (clone, 0, flags, NULL, ctid, 0);
- #elif defined(__ASSUME_CLONE_BACKWARDS3)
- ret = INLINE_SYSCALL_CALL (clone, flags, 0, 0, NULL, ctid, 0);
- #elif defined(__ASSUME_CLONE2)
- ret = INLINE_SYSCALL_CALL (clone2, flags, 0, 0, NULL, ctid, 0);
- #elif defined(__ASSUME_CLONE_DEFAULT)
- ret = INLINE_SYSCALL_CALL (clone, flags, 0, NULL, ctid, 0);
- #else
- # error "Undefined clone variant"
- #endif
- return ret;
- }
- #endif /* __ARCH_FORK_H */
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