or1k: add clone() from old GNU libc implementation

1 files changed, 49 insertions, 78 deletions

diff --git a/libc/sysdeps/linux/or1k/clone.c b/libc/sysdeps/linux/or1k/clone.c
index ebb048ad4..2b61b638f 100644
--- a/libc/sysdeps/linux/or1k/clone.c
+++ b/libc/sysdeps/linux/or1k/clone.c
@@ -1,88 +1,59 @@
-/*
- * clone syscall for OpenRISC
- *
- *  Copyright (c) 2010     Jonas Bonn <jonas@southpole.se>
- *  Copyright (C) 2003     John Williams <jwilliams@itee.uq.edu.au>
- *  Copyright (C) 2002,03  NEC Electronics Corporation
- *  Copyright (C) 2002,03  Miles Bader <miles@gnu.org>
- *
- * This file is subject to the terms and conditions of the GNU Lesser
- * General Public License.  See the file COPYING.LIB in the main
- * directory of this archive for more details.
- *
- * OpenRISC port by Jonas Bonn <jonas@southpole.se>
- */
+/* Copyright (C) 1998, 2002, 2003, 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
 
-#include <errno.h>
-#include <sys/syscall.h>
-#include <sched.h>
-#include <unistd.h>
-
-/* The userland implementation is:
-   int clone (int (*fn)(void *arg), void *child_stack, int flags, void *arg, ...)
-   the kernel entry is:
-   int clone (long flags, void *child_stack)
-*/
-
-int
-clone (int (*fn)(void *arg), void *child_stack, int flags, void *arg, ...)
-{
-        int err;
-
-	/* OK, here's the skinny on this one...
-	 * OR1K GCC does weird things with varargs functions... the last
-	 * parameter is NEVER passed on the stack -- i.e. arg, in this case.
-	 * So we need to push at least 'arg' onto the child stack so that
-	 * the new thread can find it.  Just to be totally safe, we'll
-	 * push both 'fn' and 'arg'; that way we don't need to care what
-	 * GCC does with parameters, whether they are passed in registers
-	 * or on stack.
-	 */
+   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.
 
-	/* Put 'fn' and 'arg' on child stack */
-	__asm__ __volatile__ (
-		"l.sw  -4(%0),%1;"
-		"l.sw  -8(%0),%2;"
-		:
-		: "r" (child_stack), "r" (fn), "r" (arg)
-		);
+   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.
 
-        /* Sanity check the arguments */
-        err = -EINVAL;
-        if (!fn)
-                goto syscall_error;
-        if (!child_stack)
-                goto syscall_error;
+   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/>.  */
 
-	err = INLINE_SYSCALL(clone, 2, flags, child_stack);
-
-	/* NB: from here you are in child thread or parent thread.
-	 *
-	 * Do not use any functions here that may write data _up_
-	 * onto the stack because they will overwrite the child's
-	 * thread descriptor... i.e. don't use printf
-	 */
-
-        if (err < 0)
-                goto syscall_error;
-        else if (err != 0) {
-                return err;
-	}
+#include <stdarg.h>
+#include <sysdep.h>
+#include <unistd.h>
 
-	/* NB: from here you exclusively in child thread */
+extern int __or1k_clone (int (*fn)(void *), void *child_stack,
+			 int flags, void *arg, pid_t *ptid,
+			 void *tls, pid_t *ctid);
 
-	/* Grab 'fn' and 'arg' from child stack */
-	__asm__ __volatile__ (
-		"l.lwz  %0,-4(%2);"
-		"l.lwz  %1,-8(%2);"
-		: "=&r" (fn), "=r" (arg)
-		: "r" (child_stack)
-		: "0", "1"
-		);
 
-	_exit(fn(arg));
+/* or1k ABI uses stack for varargs, syscall uses registers.
+ * This function moves from varargs to regs. */
+int
+__clone (int (*fn)(void *), void *child_stack,
+	 int flags, void *arg, ...
+	 /* pid_t *ptid, struct user_desc *tls, pid_t *ctid */ )
+{
+  void *ptid;
+  void *tls;
+  void *ctid;
+  va_list ap;
+  int err;
+
+  va_start (ap, arg);
+  ptid = va_arg (ap, void *);
+  tls = va_arg (ap, void *);
+  ctid = va_arg (ap, void *);
+  va_end (ap);
+
+  /* Sanity check the arguments */
+  err = -EINVAL;
+  if (!fn)
+    goto syscall_error;
+  if (!child_stack)
+    goto syscall_error;
+
+  return __or1k_clone (fn, child_stack, flags, arg, ptid, tls, ctid);
 
 syscall_error:
-        __set_errno (-err);
-        return -1;
+  __set_errno (-err);
+  return -1;
 }
+weak_alias (__clone, clone)