| // |
| // Copyright (C) 2014 The Android Open Source Project |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| // |
| |
| #ifndef SHILL_NET_SHILL_EXPORT_H_ |
| #define SHILL_NET_SHILL_EXPORT_H_ |
| |
| // Use SHILL_EXPORT attribute to decorate your classes, methods and variables |
| // that need to be exported out of libshill By default, any symbol not |
| // explicitly marked with SHILL_EXPORT attribute is not exported. |
| |
| // Put SHILL_EXPORT in front of methods or variables and in between the |
| // class and the tag name: |
| /* |
| |
| SHILL_EXPORT void foo(); |
| |
| class SHILL_EXPORT Bar { |
| public: |
| void baz(); // Exported since it is a member of an exported class. |
| }; |
| |
| */ |
| |
| // Exporting a class automatically exports all of its members. However there are |
| // no export entries for non-static member variables since they are not accessed |
| // directly, but rather through "this" pointer. Class methods, type information, |
| // virtual table (if any), and static member variables are exported. |
| |
| // Finally, template functions and template members of a class may not be |
| // inlined by the compiler automatically and the out-of-line version will not |
| // be exported and fail to link. Marking those inline explicitly might help. |
| // Alternatively, exporting specific instantiation of the template could be |
| // used with "extern template" and combining this with SHILL_EXPORT. |
| #define SHILL_EXPORT __attribute__((__visibility__("default"))) |
| |
| // On occasion you might need to disable exporting a particular symbol if |
| // you don't want the clients to see it. For example, you can explicitly |
| // hide a member of an exported class: |
| /* |
| |
| class SHILL_EXPORT Foo { |
| public: |
| void bar(); // Exported since it is a member of an exported class. |
| |
| private: |
| SHILL_PRIVATE void baz(); // Explicitly removed from export table. |
| }; |
| |
| */ |
| |
| // Note that even though a class may have a private member it doesn't mean |
| // that it must not be exported, since the compiler might still need it. |
| // For example, an inline public method calling a private method will not link |
| // if that private method is not exported. |
| // So be careful with hiding members if you don't want to deal with obscure |
| // linker errors. |
| #define SHILL_PRIVATE __attribute__((__visibility__("hidden"))) |
| |
| #endif // SHILL_NET_SHILL_EXPORT_H_ |