some more x86_64 source

1 files changed, 53 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/x86_64/vfork.S b/libc/sysdeps/linux/x86_64/vfork.S
new file mode 100644
index 000000000..072a3a0a8
--- /dev/null
+++ b/libc/sysdeps/linux/x86_64/vfork.S
@@ -0,0 +1,53 @@
+/* Copyright (C) 2001, 2002, 2004 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#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.  */
+
+.globl __vfork;
+.type	__vfork,@function;
+.align 16;
+__vfork:
+
+	/* Pop the return PC value into RDI.  We need a register that
+	   is preserved by the syscall and that we're allowed to destroy. */
+	popq	%rdi
+
+	/* Stuff the syscall number in RAX and enter into the kernel.  */
+	movl	$__NR_vfork, %eax
+	syscall
+
+	/* Push back the return PC.  */
+	pushq	%rdi
+
+	cmpl	$-4095, %eax
+	jae __syscall_error		/* Branch forward if it failed.  */
+
+	/* Normal return.  */
+	ret
+
+__syscall_error:
+	/* TODO: implement this ! :D */
+
+.size	 __vfork,.Lsize-__vfork
+.weak vfork ; vfork = __vfork