/*
 * This source file is part of the Swift.org open source project
 *
 * Copyright (c) 2015 Apple Inc. and the Swift project authors
 *
 * Licensed under Apache License v2.0 with Runtime Library Exception
 *
 * See http://swift.org/LICENSE.txt for license information
 * See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 *
 */

#ifndef __OS_LINUX_BASE__
#define __OS_LINUX_BASE__

#include <sys/user.h>
#include <sys/param.h>

#if __GNUC__
#define OS_EXPECT(x, v) __builtin_expect((x), (v))
#else
#define OS_EXPECT(x, v) (x)
#endif

#ifndef os_likely
#define os_likely(x) OS_EXPECT(!!(x), 1)
#endif
#ifndef os_unlikely
#define os_unlikely(x) OS_EXPECT(!!(x), 0)
#endif

#if __has_feature(assume_nonnull)
#define OS_ASSUME_NONNULL_BEGIN _Pragma("clang assume_nonnull begin")
#define OS_ASSUME_NONNULL_END   _Pragma("clang assume_nonnull end")
#else
#define OS_ASSUME_NONNULL_BEGIN
#define OS_ASSUME_NONNULL_END
#endif

#if __has_builtin(__builtin_assume)
#define OS_COMPILER_CAN_ASSUME(expr) __builtin_assume(expr)
#else
#define OS_COMPILER_CAN_ASSUME(expr) ((void)(expr))
#endif

#if __has_feature(attribute_availability_swift)
// equivalent to __SWIFT_UNAVAILABLE from Availability.h
#define OS_SWIFT_UNAVAILABLE(_msg) \
		__attribute__((__availability__(swift, unavailable, message=_msg)))
#else
#define OS_SWIFT_UNAVAILABLE(_msg)
#endif

#if __has_attribute(swift_private)
# define OS_REFINED_FOR_SWIFT __attribute__((__swift_private__))
#else
# define OS_REFINED_FOR_SWIFT
#endif

#if __has_attribute(swift_name)
# define OS_SWIFT_NAME(_name) __attribute__((__swift_name__(#_name)))
#else
# define OS_SWIFT_NAME(_name)
#endif

#define __OS_STRINGIFY(s) #s
#define OS_STRINGIFY(s) __OS_STRINGIFY(s)
#define __OS_CONCAT(x, y) x ## y
#define OS_CONCAT(x, y) __OS_CONCAT(x, y)

/*
 * Stub out misc linking and compilation attributes
 */

#ifdef OS_EXPORT
#undef OS_EXPORT
#endif
#define OS_EXPORT

#ifdef OS_WARN_RESULT_NEEDS_RELEASE
#undef OS_WARN_RESULT_NEEDS_RELEASE
#endif

#ifdef OS_WARN_RESULT
#undef OS_WARN_RESULT
#endif
#define OS_WARN_RESULT

#ifdef OS_NOTHROW
#undef OS_NOTHROW
#endif
#define OS_NOTHROW

#endif /* __OS_LINUX_BASE__ */