// Copyright 2014 The Chromium OS Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef LIBBRILLO_BRILLO_BRILLO_EXPORT_H_ #define LIBBRILLO_BRILLO_BRILLO_EXPORT_H_ // Use BRILLO_EXPORT attribute to decorate your classes, methods and variables // that need to be exported out of libbrillo. By default, any symbol not // explicitly marked with BRILLO_EXPORT attribute is not exported. // Put BRILLO_EXPORT in front of methods or variables and in between the // class and the tag name: /* BRILLO_EXPORT void foo(); class BRILLO_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 BRILLO_EXPORT. #define BRILLO_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 BRILLO_EXPORT Foo { public: void bar(); // Exported since it is a member of an exported class. private: BRILLO_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 BRILLO_PRIVATE __attribute__((__visibility__("hidden"))) #endif // LIBBRILLO_BRILLO_BRILLO_EXPORT_H_