00001 // Copyright 2017 The Abseil Authors. 00002 // 00003 // Licensed under the Apache License, Version 2.0 (the "License"); 00004 // you may not use this file except in compliance with the License. 00005 // You may obtain a copy of the License at 00006 // 00007 // https://www.apache.org/licenses/LICENSE-2.0 00008 // 00009 // Unless required by applicable law or agreed to in writing, software 00010 // distributed under the License is distributed on an "AS IS" BASIS, 00011 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 00012 // See the License for the specific language governing permissions and 00013 // limitations under the License. 00014 00015 #ifndef ABSL_BASE_INTERNAL_PER_THREAD_TLS_H_ 00016 #define ABSL_BASE_INTERNAL_PER_THREAD_TLS_H_ 00017 00018 // This header defines two macros: 00019 // 00020 // If the platform supports thread-local storage: 00021 // 00022 // * ABSL_PER_THREAD_TLS_KEYWORD is the C keyword needed to declare a 00023 // thread-local variable 00024 // * ABSL_PER_THREAD_TLS is 1 00025 // 00026 // Otherwise: 00027 // 00028 // * ABSL_PER_THREAD_TLS_KEYWORD is empty 00029 // * ABSL_PER_THREAD_TLS is 0 00030 // 00031 // Microsoft C supports thread-local storage. 00032 // GCC supports it if the appropriate version of glibc is available, 00033 // which the programmer can indicate by defining ABSL_HAVE_TLS 00034 00035 #include "absl/base/port.h" // For ABSL_HAVE_TLS 00036 00037 #if defined(ABSL_PER_THREAD_TLS) 00038 #error ABSL_PER_THREAD_TLS cannot be directly set 00039 #elif defined(ABSL_PER_THREAD_TLS_KEYWORD) 00040 #error ABSL_PER_THREAD_TLS_KEYWORD cannot be directly set 00041 #elif defined(ABSL_HAVE_TLS) 00042 #define ABSL_PER_THREAD_TLS_KEYWORD __thread 00043 #define ABSL_PER_THREAD_TLS 1 00044 #elif defined(_MSC_VER) 00045 #define ABSL_PER_THREAD_TLS_KEYWORD __declspec(thread) 00046 #define ABSL_PER_THREAD_TLS 1 00047 #else 00048 #define ABSL_PER_THREAD_TLS_KEYWORD 00049 #define ABSL_PER_THREAD_TLS 0 00050 #endif 00051 00052 #endif // ABSL_BASE_INTERNAL_PER_THREAD_TLS_H_