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-rw-r--r--sysdeps/unix/sysv/linux/i386/vfork.S66
1 files changed, 66 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/vfork.S b/sysdeps/unix/sysv/linux/i386/vfork.S
new file mode 100644
index 0000000000..118fccb613
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/i386/vfork.S
@@ -0,0 +1,66 @@
+/* Copyright (C) 1999 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 Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  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>
+
+/* 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)
+
+#ifdef __NR_vfork
+
+	/* Pop the return PC value into ECX.  */
+	popl	%ecx
+
+	/* Stuff the syscall number in EAX and enter into the kernel.  */
+	movl	$SYS_ify (vfork), %eax
+	int	$0x80
+	cmpl	$-4095, %eax
+	jae	.Lerror		/* Branch forward if it failed.  */
+
+	/* Jump to the return PC.  */
+	jmp	*%ecx
+
+.Lerror:
+	/* Push back the return PC.  */
+	pushl	%ecx
+
+	/* Check if vfork syscall is known at all.  */
+	cmpl	$-ENOSYS, %eax
+	jne	SYSCALL_ERROR_LABEL
+
+#endif
+
+	/* If we don't have vfork, fork is close enough.  */
+
+	movl	$SYS_ify (fork), %eax
+	int	$0x80
+	cmpl	$-4095, %eax
+	jae	SYSCALL_ERROR_LABEL
+.Lpseudo_end:
+	ret
+
+PSEUDO_END (__vfork)
+
+weak_alias (__vfork, vfork)