// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// SPDX-FileCopyrightText: Copyright (c) 2023 NVIDIA CORPORATION & AFFILIATES.
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCUDACXX___AVAILABILITY
#define _LIBCUDACXX___AVAILABILITY

#include <cuda/std/detail/__config>

#if defined(_CCCL_IMPLICIT_SYSTEM_HEADER_GCC)
#  pragma GCC system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_CLANG)
#  pragma clang system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_MSVC)
#  pragma system_header
#endif // no system header

// Libc++ is shipped by various vendors. In particular, it is used as a system
// library on macOS, iOS and other Apple platforms. In order for users to be
// able to compile a binary that is intended to be deployed to an older version
// of a platform, Clang provides availability attributes [1]. These attributes
// can be placed on declarations and are used to describe the life cycle of a
// symbol in the library.
//
// The main goal is to ensure a compile-time error if a symbol that hasn't been
// introduced in a previously released library is used in a program that targets
// that previously released library. Normally, this would be a load-time error
// when one tries to launch the program against the older library.
//
// For example, the filesystem library was introduced in the dylib in macOS 10.15.
// If a user compiles on a macOS 10.15 host but targets macOS 10.13 with their
// program, the compiler would normally not complain (because the required
// declarations are in the headers), but the dynamic loader would fail to find
// the symbols when actually trying to launch the program on macOS 10.13. To
// turn this into a compile-time issue instead, declarations are annotated with
// when they were introduced, and the compiler can produce a diagnostic if the
// program references something that isn't available on the deployment target.
//
// This mechanism is general in nature, and any vendor can add their markup to
// the library (see below). Whenever a new feature is added that requires support
// in the shared library, a macro should be added below to mark this feature
// as unavailable. When vendors decide to ship the feature as part of their
// shared library, they can update the markup appropriately.
//
// Furthermore, many features in the standard library have corresponding
// feature-test macros. When a feature is made unavailable on some deployment
// target, a macro should be defined to signal that it is unavailable. That
// macro can then be picked up when feature-test macros are generated (see
// generate_feature_test_macro_components.py) to make sure that feature-test
// macros don't announce a feature as being implemented if it has been marked
// as unavailable.
//
// Note that this mechanism is disabled by default in the "upstream" libc++.
// Availability annotations are only meaningful when shipping libc++ inside
// a platform (i.e. as a system library), and so vendors that want them should
// turn those annotations on at CMake configuration time.
//
// [1]: https://clang.llvm.org/docs/AttributeReference.html#availability

// For backwards compatibility, allow users to define _LIBCUDACXX_DISABLE_AVAILABILITY
// for a while.
#if defined(_LIBCUDACXX_DISABLE_AVAILABILITY)
#  if !defined(_LIBCUDACXX_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)
#    define _LIBCUDACXX_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
#  endif
#endif

// Availability markup is disabled when building the library, or when the compiler
// doesn't support the proper attributes.
#if defined(_LIBCUDACXX_BUILDING_LIBRARY) || defined(_LIBCXXABI_BUILDING_LIBRARY)                              \
  || !__has_feature(attribute_availability_with_strict) || !__has_feature(attribute_availability_in_templates) \
  || !__has_extension(pragma_clang_attribute_external_declaration)
#  if !defined(_LIBCUDACXX_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)
#    define _LIBCUDACXX_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
#  endif
#endif

#if defined(_LIBCUDACXX_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)

// This controls the availability of std::shared_mutex and std::shared_timed_mutex,
// which were added to the dylib later.
#  define _LIBCUDACXX_AVAILABILITY_SHARED_MUTEX
// #   define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_shared_mutex
// #   define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_shared_timed_mutex

// These macros control the availability of std::bad_optional_access and
// other exception types. These were put in the shared library to prevent
// code bloat from every user program defining the vtable for these exception
// types.
//
// Note that when exceptions are disabled, the methods that normally throw
// these exceptions can be used even on older deployment targets, but those
// methods will abort instead of throwing.
#  define _LIBCUDACXX_AVAILABILITY_BAD_OPTIONAL_ACCESS
#  define _LIBCUDACXX_AVAILABILITY_BAD_VARIANT_ACCESS
#  define _LIBCUDACXX_AVAILABILITY_BAD_ANY_CAST

// This controls the availability of std::uncaught_exceptions().
#  define _LIBCUDACXX_AVAILABILITY_UNCAUGHT_EXCEPTIONS

// This controls the availability of the sized version of ::operator delete,
// ::operator delete[], and their align_val_t variants, which were all added
// in C++17, and hence not present in early dylibs.
#  define _LIBCUDACXX_AVAILABILITY_SIZED_NEW_DELETE

// This controls the availability of the std::future_error exception.
//
// Note that when exceptions are disabled, the methods that normally throw
// std::future_error can be used even on older deployment targets, but those
// methods will abort instead of throwing.
#  define _LIBCUDACXX_AVAILABILITY_FUTURE_ERROR

// This controls the availability of std::type_info's vtable.
// I can't imagine how using std::type_info can work at all if
// this isn't supported.
#  define _LIBCUDACXX_AVAILABILITY_TYPEINFO_VTABLE

// This controls the availability of std::locale::category members
// (e.g. std::locale::collate), which are defined in the dylib.
#  define _LIBCUDACXX_AVAILABILITY_LOCALE_CATEGORY

// This controls the availability of atomic operations on std::shared_ptr
// (e.g. `std::atomic_store(std::shared_ptr)`), which require a shared
// lock table located in the dylib.
#  define _LIBCUDACXX_AVAILABILITY_ATOMIC_SHARED_PTR

// These macros control the availability of all parts of <filesystem> that
// depend on something in the dylib.
#  define _LIBCUDACXX_AVAILABILITY_FILESYSTEM
#  define _LIBCUDACXX_AVAILABILITY_FILESYSTEM_PUSH
#  define _LIBCUDACXX_AVAILABILITY_FILESYSTEM_POP
// #   define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_filesystem

// This controls the availability of floating-point std::to_chars functions.
// These overloads were added later than the integer overloads.
#  define _LIBCUDACXX_AVAILABILITY_TO_CHARS_FLOATING_POINT

// This controls the availability of the C++20 synchronization library,
// which requires shared library support for various operations
// (see libcxx/src/atomic.cpp). This includes <barier>, <latch>,
// <semaphore>, and notification functions on std::atomic.
#  define _LIBCUDACXX_AVAILABILITY_SYNC
// #   define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_atomic_wait
// #   define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_barrier
// #   define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_latch
// #   define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_semaphore

// This controls the availability of the C++20 format library.
// The library is in development and not ABI stable yet. P2216 is
// retroactively accepted in C++20. This paper contains ABI breaking
// changes.
#  define _LIBCUDACXX_AVAILABILITY_FORMAT
// #   define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_format

// This controls whether the default verbose termination function is
// provided by the library.
//
// Note that when users provide their own custom function, it doesn't
// matter whether the dylib provides a default function, and the
// availability markup can actually give a false positive diagnostic
// (it will think that no function is provided, when in reality the
// user has provided their own).
//
// Users can pass -D_LIBCUDACXX_AVAILABILITY_CUSTOM_VERBOSE_ABORT_PROVIDED
// to the compiler to tell the library not to define its own verbose abort.
// Note that defining this macro but failing to define a custom function
// will lead to a load-time error on back-deployment targets, so it should
// be avoided.
// #   define _LIBCUDACXX_HAS_NO_VERBOSE_ABORT_IN_LIBRARY

#elif defined(__APPLE__)

#  define _LIBCUDACXX_AVAILABILITY_SHARED_MUTEX                      \
    __attribute__((availability(macos, strict, introduced = 10.12))) \
    __attribute__((availability(ios, strict, introduced = 10.0)))    \
    __attribute__((availability(tvos, strict, introduced = 10.0)))   \
    __attribute__((availability(watchos, strict, introduced = 3.0)))
#  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)                                                       \
       && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101200)                                                   \
    || (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__)                                                     \
        && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 100000)                                                 \
    || (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 100000) \
    || (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__)                                                      \
        && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 30000)
#    define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_shared_mutex
#    define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_shared_timed_mutex
#  endif

// Note: bad_optional_access & friends were not introduced in the matching
// macOS and iOS versions, so the version mismatch between macOS and others
// is intended.
#  define _LIBCUDACXX_AVAILABILITY_BAD_OPTIONAL_ACCESS               \
    __attribute__((availability(macos, strict, introduced = 10.13))) \
    __attribute__((availability(ios, strict, introduced = 12.0)))    \
    __attribute__((availability(tvos, strict, introduced = 12.0)))   \
    __attribute__((availability(watchos, strict, introduced = 5.0)))
#  define _LIBCUDACXX_AVAILABILITY_BAD_VARIANT_ACCESS _LIBCUDACXX_AVAILABILITY_BAD_OPTIONAL_ACCESS
#  define _LIBCUDACXX_AVAILABILITY_BAD_ANY_CAST       _LIBCUDACXX_AVAILABILITY_BAD_OPTIONAL_ACCESS

#  define _LIBCUDACXX_AVAILABILITY_UNCAUGHT_EXCEPTIONS               \
    __attribute__((availability(macos, strict, introduced = 10.12))) \
    __attribute__((availability(ios, strict, introduced = 10.0)))    \
    __attribute__((availability(tvos, strict, introduced = 10.0)))   \
    __attribute__((availability(watchos, strict, introduced = 3.0)))

#  define _LIBCUDACXX_AVAILABILITY_SIZED_NEW_DELETE                  \
    __attribute__((availability(macos, strict, introduced = 10.12))) \
    __attribute__((availability(ios, strict, introduced = 10.0)))    \
    __attribute__((availability(tvos, strict, introduced = 10.0)))   \
    __attribute__((availability(watchos, strict, introduced = 3.0)))

#  define _LIBCUDACXX_AVAILABILITY_FUTURE_ERROR __attribute__((availability(ios, strict, introduced = 6.0)))

#  define _LIBCUDACXX_AVAILABILITY_TYPEINFO_VTABLE                  \
    __attribute__((availability(macos, strict, introduced = 10.9))) \
    __attribute__((availability(ios, strict, introduced = 7.0)))

#  define _LIBCUDACXX_AVAILABILITY_LOCALE_CATEGORY                  \
    __attribute__((availability(macos, strict, introduced = 10.9))) \
    __attribute__((availability(ios, strict, introduced = 7.0)))

#  define _LIBCUDACXX_AVAILABILITY_ATOMIC_SHARED_PTR                \
    __attribute__((availability(macos, strict, introduced = 10.9))) \
    __attribute__((availability(ios, strict, introduced = 7.0)))

#  define _LIBCUDACXX_AVAILABILITY_FILESYSTEM                        \
    __attribute__((availability(macos, strict, introduced = 10.15))) \
    __attribute__((availability(ios, strict, introduced = 13.0)))    \
    __attribute__((availability(tvos, strict, introduced = 13.0)))   \
    __attribute__((availability(watchos, strict, introduced = 6.0)))
#  define _LIBCUDACXX_AVAILABILITY_FILESYSTEM_PUSH                                                      \
    _Pragma("clang attribute push(__attribute__((availability(macos,strict,introduced=10.15))), "       \
            "apply_to=any(function,record))")                                                           \
      _Pragma("clang attribute push(__attribute__((availability(ios,strict,introduced=13.0))), "        \
              "apply_to=any(function,record))")                                                         \
        _Pragma("clang attribute push(__attribute__((availability(tvos,strict,introduced=13.0))), "     \
                "apply_to=any(function,record))")                                                       \
          _Pragma("clang attribute push(__attribute__((availability(watchos,strict,introduced=6.0))), " \
                  "apply_to=any(function,record))")
#  define _LIBCUDACXX_AVAILABILITY_FILESYSTEM_POP                                                \
    _Pragma("clang attribute pop") _Pragma("clang attribute pop") _Pragma("clang attribute pop") \
      _Pragma("clang attribute pop")
#  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)                                                       \
       && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101500)                                                   \
    || (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__)                                                     \
        && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 130000)                                                 \
    || (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 130000) \
    || (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__)                                                      \
        && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 60000)
#    define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_filesystem
#  endif

#  define _LIBCUDACXX_AVAILABILITY_TO_CHARS_FLOATING_POINT __attribute__((unavailable))

#  define _LIBCUDACXX_AVAILABILITY_SYNC                             \
    __attribute__((availability(macos, strict, introduced = 11.0))) \
    __attribute__((availability(ios, strict, introduced = 14.0)))   \
    __attribute__((availability(tvos, strict, introduced = 14.0)))  \
    __attribute__((availability(watchos, strict, introduced = 7.0)))
#  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)                                                       \
       && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 110000)                                                   \
    || (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__)                                                     \
        && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 140000)                                                 \
    || (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 140000) \
    || (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__)                                                      \
        && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 70000)
#    define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_atomic_wait
#    define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_barrier
#    define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_latch
#    define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_semaphore
#  endif

#  define _LIBCUDACXX_AVAILABILITY_FORMAT __attribute__((unavailable))
#  define _LIBCUDACXX_AVAILABILITY_DISABLE_FTM___cpp_lib_format

#  define _LIBCUDACXX_HAS_NO_VERBOSE_ABORT_IN_LIBRARY

#else

// ...New vendors can add availability markup here...

#  error \
    "It looks like you're trying to enable vendor availability markup, but you haven't defined the corresponding macros yet!"

#endif

// Define availability attributes that depend on _CCCL_NO_EXCEPTIONS.
// Those are defined in terms of the availability attributes above, and
// should not be vendor-specific.
#if defined(_CCCL_NO_EXCEPTIONS)
#  define _LIBCUDACXX_AVAILABILITY_FUTURE
#  define _LIBCUDACXX_AVAILABILITY_THROW_BAD_ANY_CAST
#  define _LIBCUDACXX_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS
#  define _LIBCUDACXX_AVAILABILITY_THROW_BAD_VARIANT_ACCESS
#else
#  define _LIBCUDACXX_AVAILABILITY_FUTURE                    _LIBCUDACXX_AVAILABILITY_FUTURE_ERROR
#  define _LIBCUDACXX_AVAILABILITY_THROW_BAD_ANY_CAST        _LIBCUDACXX_AVAILABILITY_BAD_ANY_CAST
#  define _LIBCUDACXX_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS _LIBCUDACXX_AVAILABILITY_BAD_OPTIONAL_ACCESS
#  define _LIBCUDACXX_AVAILABILITY_THROW_BAD_VARIANT_ACCESS  _LIBCUDACXX_AVAILABILITY_BAD_VARIANT_ACCESS
#endif

#endif // _LIBCUDACXX___AVAILABILITY
