zircon/system/ulib/zircon/private.h

// Copyright 2016 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef ZIRCON_SYSTEM_ULIB_ZIRCON_PRIVATE_H_
#define ZIRCON_SYSTEM_ULIB_ZIRCON_PRIVATE_H_

#include <zircon/compiler.h>
#include <zircon/syscalls.h>

// This defines the struct shared with the kernel.
#include <lib/userabi/vdso-constants.h>

extern __LOCAL const struct vdso_constants DATA_CONSTANTS;

extern "C" {

// This declares the VDSO_zx_* aliases for the vDSO entry points.
// Calls made from within the vDSO must use these names rather than
// the public names so as to avoid PLT entries.
#include <zircon/syscall-vdso-definitions.h>

__LOCAL decltype(zx_clock_get_monotonic) CODE_clock_get_monotonic_via_kernel_ticks;
__LOCAL decltype(zx_deadline_after) CODE_deadline_after_via_kernel_mono;
__LOCAL decltype(zx_deadline_after) CODE_deadline_after_via_kernel_ticks;
}

// Code should define '_zx_foo' and then do 'VDSO_INTERFACE_FUNCTION(zx_foo);'
// to define the public name 'zx_foo' and the vDSO-private name 'VDSO_zx_foo'.
#define VDSO_INTERFACE_FUNCTION(name)          \
  decltype(name) name __WEAK_ALIAS("_" #name); \
  decltype(name) VDSO_##name __LOCAL __ALIAS("_" #name)

// This symbol is expected to appear in the build-time vDSO symbol table so
// kernel/lib/userabi/ code can use it.
#define VDSO_KERNEL_EXPORT __attribute__((used))

#endif  // ZIRCON_SYSTEM_ULIB_ZIRCON_PRIVATE_H_