Linux sandbox: start adding syscall wrappers

sandbox/linux/services/syscall_wrappers.cc

Index: sandbox/linux/services/syscall_wrappers.cc
diff --git a/sandbox/linux/services/syscall_wrappers.cc b/sandbox/linux/services/syscall_wrappers.cc
new file mode 100644
index 0000000000000000000000000000000000000000..46fe3e5c4bbefd54544d90a27fade15c6a9e6b4c
--- /dev/null
+++ b/sandbox/linux/services/syscall_wrappers.cc
@@ -0,0 +1,35 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "sandbox/linux/services/syscall_wrappers.h"
+
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "sandbox/linux/services/linux_syscalls.h"
+
+namespace sandbox {
+
+pid_t sys_getpid(void) {
+  return syscall(__NR_getpid);
+}
+
+pid_t sys_gettid(void) {
+  return syscall(__NR_gettid);
+}
+
+long sys_clone(unsigned long flags,
+               void* child_stack,
+               void* ptid,
+               void* ctid,
+               struct pt_regs* regs) {
+  return syscall(__NR_clone, flags, child_stack, ptid, ctid, regs);
+}
+
+void sys_exit_group(int status) {
+  syscall(__NR_exit_group, status);
+}
+
+}  // namespace sandbox