mbed_preprocessor.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2019 ARM Limited
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License");
00006  * you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  *     http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS,
00013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 #ifndef MBED_PREPROCESSOR_H
00018 #define MBED_PREPROCESSOR_H
00019 
00020 /** \addtogroup platform-public-api */
00021 /** @{*/
00022 
00023 /**
00024  * \defgroup platform_preprocessor preprocessor macros
00025  * @{
00026  */
00027 
00028 /** MBED_CONCAT
00029  *  Concatenate tokens together
00030  *
00031  *  @note
00032  *  Expands tokens before concatenation
00033  *
00034  *  @code
00035  *  // Creates a unique label based on the line number
00036  *  int MBED_CONCAT(UNIQUE_LABEL_, __LINE__) = 1;
00037  *  @endcode
00038  */
00039 #define MBED_CONCAT(a, b) MBED_CONCAT_(a, b)
00040 #define MBED_CONCAT_(a, b) a##b
00041 
00042 /** MBED_STRINGIFY
00043  *  Converts tokens into strings
00044  *
00045  *  @note
00046  *  Expands tokens before stringification
00047  *
00048  *  @code
00049  *  // Creates a string based on the parameters
00050  *  const char *c = MBED_STRINGIFY(This is a ridiculous way to create a string)
00051  *  @endcode
00052  */
00053 #define MBED_STRINGIFY(a) MBED_STRINGIFY_(a)
00054 #define MBED_STRINGIFY_(a) #a
00055 
00056 /** MBED_STRLEN
00057  *  Reports string token length
00058  *
00059  *  @note
00060  *  Expands tokens before calculating length
00061  *
00062  *  @code
00063  *  // Get string length
00064  *  const int len = MBED_STRLEN("Get the length")
00065  *  @endcode
00066  */
00067 #define MBED_STRLEN(a) MBED_STRLEN_(a)
00068 #define MBED_STRLEN_(a) (sizeof(a) - 1)
00069 
00070 /** MBED_COUNT_VA_ARGS(...)
00071  *  Reports number of tokens passed
00072  *
00073  *  @note
00074  *  Token limit is 16
00075  *
00076  *  @code
00077  *  // Get number of arguments
00078  *  const int count = MBED_COUNT_VA_ARGS("Address 0x%x, Data[0] = %d Data[1] = %d", 0x20001234, 10, 20)
00079  *  @endcode
00080  */
00081 #define MBED_COUNT_VA_ARGS(...) GET_NTH_ARG_(__VA_ARGS__, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1)
00082 #define GET_NTH_ARG_(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, N, ...) N
00083 
00084 #endif
00085 
00086 /** @}*/
00087 /** @}*/