Program Listing for File macros.h
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// Copyright The OpenTelemetry Authors
// SPDX-License-Identifier: Apache-2.0
#pragma once
#if !defined(OPENTELEMETRY_LIKELY_IF) && defined(__cplusplus)
// GCC 9 has likely attribute but do not support declare it at the beginning of statement
# if defined(__has_cpp_attribute) && (defined(__clang__) || !defined(__GNUC__) || __GNUC__ > 9)
# if __has_cpp_attribute(likely)
# define OPENTELEMETRY_LIKELY_IF(...) \
if (__VA_ARGS__) \
[[likely]]
# endif
# endif
#endif
#if !defined(OPENTELEMETRY_LIKELY_IF) && (defined(__clang__) || defined(__GNUC__))
# define OPENTELEMETRY_LIKELY_IF(...) if (__builtin_expect(!!(__VA_ARGS__), true))
#endif
#ifndef OPENTELEMETRY_LIKELY_IF
# define OPENTELEMETRY_LIKELY_IF(...) if (__VA_ARGS__)
#endif
#if defined(__cplusplus) && __cplusplus >= 201703L
# define OPENTELEMETRY_MAYBE_UNUSED [[maybe_unused]]
#elif defined(__clang__)
# define OPENTELEMETRY_MAYBE_UNUSED __attribute__((unused))
#elif defined(__GNUC__) && ((__GNUC__ >= 4) || ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 1)))
# define OPENTELEMETRY_MAYBE_UNUSED __attribute__((unused))
#elif (defined(_MSC_VER) && _MSC_VER >= 1910) && (defined(_MSVC_LANG) && _MSVC_LANG >= 201703L)
# define OPENTELEMETRY_MAYBE_UNUSED [[maybe_unused]]
#else
# define OPENTELEMETRY_MAYBE_UNUSED
#endif
#ifndef OPENTELEMETRY_RTTI_ENABLED
# if defined(__clang__)
# if __has_feature(cxx_rtti)
# define OPENTELEMETRY_RTTI_ENABLED
# endif
# elif defined(__GNUG__)
# if defined(__GXX_RTTI)
# define OPENTELEMETRY_RTTI_ENABLED
# endif
# elif defined(_MSC_VER)
# if defined(_CPPRTTI)
# define OPENTELEMETRY_RTTI_ENABLED
# endif
# endif
#endif
#if defined(__cplusplus) && __cplusplus >= 201402L
# define OPENTELEMETRY_DEPRECATED [[deprecated]]
#elif defined(__clang__)
# define OPENTELEMETRY_DEPRECATED __attribute__((deprecated))
#elif defined(__GNUC__)
# define OPENTELEMETRY_DEPRECATED __attribute__((deprecated))
#elif defined(_MSC_VER)
# if _MSC_VER >= 1910 && defined(_MSVC_LANG) && _MSVC_LANG >= 201703L
# define OPENTELEMETRY_DEPRECATED [[deprecated]]
# else
# define OPENTELEMETRY_DEPRECATED __declspec(deprecated)
# endif
#else
# define OPENTELEMETRY_DEPRECATED
#endif
#if defined(__cplusplus) && __cplusplus >= 201402L
# define OPENTELEMETRY_DEPRECATED_MESSAGE(msg) [[deprecated(msg)]]
#elif defined(__clang__)
# define OPENTELEMETRY_DEPRECATED_MESSAGE(msg) __attribute__((deprecated(msg)))
#elif defined(__GNUC__)
# define OPENTELEMETRY_DEPRECATED_MESSAGE(msg) __attribute__((deprecated(msg)))
#elif defined(_MSC_VER)
# if _MSC_VER >= 1910 && defined(_MSVC_LANG) && _MSVC_LANG >= 201703L
# define OPENTELEMETRY_DEPRECATED_MESSAGE(msg) [[deprecated(msg)]]
# else
# define OPENTELEMETRY_DEPRECATED_MESSAGE(msg) __declspec(deprecated(msg))
# endif
#else
# define OPENTELEMETRY_DEPRECATED_MESSAGE(msg)
#endif
// Regex support
#if (__GNUC__ == 4 && (__GNUC_MINOR__ == 8 || __GNUC_MINOR__ == 9))
# define OPENTELEMETRY_HAVE_WORKING_REGEX 0
#else
# define OPENTELEMETRY_HAVE_WORKING_REGEX 1
#endif
/* clang-format off */
/* clang-format on */
#if defined(__clang__)
# define OPENTELEMETRY_API_SINGLETON __attribute__((visibility("default")))
#elif defined(__GNUC__)
# define OPENTELEMETRY_API_SINGLETON __attribute__((visibility("default")))
#else
/* Add support for other compilers here. */
# define OPENTELEMETRY_API_SINGLETON
#endif
//
// Atomic wrappers based on compiler intrinsics for memory read/write.
// The tailing number is read/write length in bits.
//
// N.B. Compiler instrinsic is used because the usage of C++ standard library is restricted in the
// OpenTelemetry C++ API.
//
#if defined(__GNUC__)
# define OPENTELEMETRY_ATOMIC_READ_8(ptr) __atomic_load_n(ptr, __ATOMIC_SEQ_CST)
# define OPENTELEMETRY_ATOMIC_WRITE_8(ptr, value) __atomic_store_n(ptr, value, __ATOMIC_SEQ_CST)
#elif defined(_MSC_VER)
# include <intrin.h>
# define OPENTELEMETRY_ATOMIC_READ_8(ptr) \
static_cast<uint8_t>(_InterlockedCompareExchange8(reinterpret_cast<char *>(ptr), 0, 0))
# define OPENTELEMETRY_ATOMIC_WRITE_8(ptr, value) \
_InterlockedExchange8(reinterpret_cast<char *>(ptr), static_cast<char>(value))
#else
# error port atomics read/write for the current platform
#endif
/* clang-format on */
//
// The if/elif order matters here. If both OPENTELEMETRY_BUILD_IMPORT_DLL and
// OPENTELEMETRY_BUILD_EXPORT_DLL are defined, the former takes precedence.
//
// TODO: consider define OPENTELEMETRY_EXPORT for cygwin/gcc, see below link.
// https://gcc.gnu.org/wiki/Visibility#How_to_use_the_new_C.2B-.2B-_visibility_support
//
#if defined(_MSC_VER) && defined(OPENTELEMETRY_BUILD_IMPORT_DLL)
# define OPENTELEMETRY_EXPORT __declspec(dllimport)
#elif defined(_MSC_VER) && defined(OPENTELEMETRY_BUILD_EXPORT_DLL)
# define OPENTELEMETRY_EXPORT __declspec(dllexport)
#else
//
// build OpenTelemetry as static library or not on Windows.
//
# define OPENTELEMETRY_EXPORT
#endif