1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef CHRE_UTIL_MACROS_H_
18 #define CHRE_UTIL_MACROS_H_
19 
20 #ifndef UNUSED_VAR
21 #define UNUSED_VAR(var) ((void)(var))
22 #endif
23 
24 /**
25  * Obtains the number of elements in a C-style array.
26  */
27 #define ARRAY_SIZE(array) (sizeof(array) / sizeof((array)[0]))
28 #define ARRAY_END(array) (array + ARRAY_SIZE(array))
29 
30 /**
31  * Performs macro expansion then converts the value into a string literal
32  */
33 #define STRINGIFY(x) STRINGIFY2(x)
34 #define STRINGIFY2(x) #x
35 
36 // Compiler-specific functionality
37 #if defined(__clang__) || defined(__GNUC__)
38 
39 //! Exports a symbol so it is accessible outside the .so (symbols are hidden by
40 //! default)
41 #define DLL_EXPORT __attribute__((visibility("default")))
42 
43 //! Marks a symbol as weak, so that it may be overridden at link time
44 #define WEAK_SYMBOL __attribute__((weak))
45 
46 #else
47 
48 #warning "Missing compiler-specific macros"
49 
50 #endif
51 
52 #endif  // CHRE_UTIL_MACROS_H_
53