| 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768 |
- /* Copyright (C) 1999, 2002, 2004 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Andreas Schwab <schwab@gnu.org>.
- 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, write to the Free
- Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- 02111-1307 USA. */
- #include <sysdep.h>
- #define _ERRNO_H 1
- #include <bits/errno.h>
- #include <bits/kernel-features.h>
- #include <tcb-offsets.h>
- /* Save the PID value. */
- #define SAVE_PID \
- movl %gs:PID, %edx; \
- movl %edx, %eax; \
- negl %eax; \
- movl %eax, %gs:PID
- /* Restore the old PID value in the parent. */
- #define RESTORE_PID \
- testl %eax, %eax; \
- je 1f; \
- movl %edx, %gs:PID; \
- 1:
- /* Clone the calling process, but without copying the whole address space.
- The calling process is suspended until the new process exits or is
- replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
- and the process ID of the new process to the old process. */
- ENTRY (__vfork)
- /* Pop the return PC value into ECX. */
- popl %ecx
- SAVE_PID
- /* Stuff the syscall number in EAX and enter into the kernel. */
- movl $SYS_ify (vfork), %eax
- int $0x80
- RESTORE_PID
- /* Jump to the return PC. Don't jump directly since this
- disturbs the branch target cache. Instead push the return
- address back on the stack. */
- pushl %ecx
- cmpl $-4095, %eax
- jae SYSCALL_ERROR_LABEL /* Branch forward if it failed. */
- L(pseudo_end):
- ret
- PSEUDO_END (__vfork)
- weak_alias (__vfork, vfork)
|
