1 /*
2  *  Copyright 2016 The WebRTC Project Authors. All rights reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef SDK_OBJC_BASE_RTCMACROS_H_
12 #define SDK_OBJC_BASE_RTCMACROS_H_
13 
14 // Internal macros used to correctly concatenate symbols.
15 #define RTC_SYMBOL_CONCAT_HELPER(a, b) a##b
16 #define RTC_SYMBOL_CONCAT(a, b) RTC_SYMBOL_CONCAT_HELPER(a, b)
17 
18 // RTC_OBJC_TYPE_PREFIX
19 //
20 // Macro used to prepend a prefix to the API types that are exported with
21 // RTC_OBJC_EXPORT.
22 //
23 // Clients can patch the definition of this macro locally and build
24 // WebRTC.framework with their own prefix in case symbol clashing is a
25 // problem.
26 //
27 // This macro must only be defined here and not on via compiler flag to
28 // ensure it has a unique value.
29 #define RTC_OBJC_TYPE_PREFIX
30 
31 // RCT_OBJC_TYPE
32 //
33 // Macro used internally to declare API types. Declaring an API type without
34 // using this macro will not include the declared type in the set of types
35 // that will be affected by the configurable RTC_OBJC_TYPE_PREFIX.
36 #define RTC_OBJC_TYPE(type_name) RTC_SYMBOL_CONCAT(RTC_OBJC_TYPE_PREFIX, type_name)
37 
38 #define RTC_OBJC_EXPORT __attribute__((visibility("default")))
39 
40 #if defined(__cplusplus)
41 #define RTC_EXTERN extern "C" RTC_OBJC_EXPORT
42 #else
43 #define RTC_EXTERN extern RTC_OBJC_EXPORT
44 #endif
45 
46 #ifdef __OBJC__
47 #define RTC_FWD_DECL_OBJC_CLASS(classname) @class classname
48 #else
49 #define RTC_FWD_DECL_OBJC_CLASS(classname) typedef struct objc_object classname
50 #endif
51 
52 #endif  // SDK_OBJC_BASE_RTCMACROS_H_
53