components/esp_common/include/esp_macros.h (ESP-IDF)

/* * SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD * * SPDX-License-Identifier: Apache-2.0 */ #pragma once /* This header contains various general purpose helper macros used across ESP-IDF */ #include <assert.h> #include "esp_assert.h" #include "esp_compiler.h" #ifdef __cplusplus extern "C" { #endif /** * @brief Macro to select different versions of other macros based on whether VA_ARGS has an argument or no argument * * Some macros (such as in FreeRTOS) have two versions (one that accepts arguments and another that does not). The * following "CHOOSE_MACRO_VA_ARG" selector allows automatic selection between two different versions of a macro. * * "CHOOSE_MACRO_VA_ARG" make use of the fact that "##__VA_ARGS__," will eliminate the trailing comma if there are no * arguments, thus allows subsequent arguments in "CHOOSE_MACRO_VA_ARG" to be left shifted in the parameter list. * * Therefore, if we call the following: * - CHOOSE_MACRO_VA_ARG(MACRO_ARGS, MACRO_NO_ARGS, ##__VA_ARGS__)(__VA_ARGS__) * * The result will be: * - MACRO_ARGS(__VA_ARGS__) if __VA_ARGS__ was not empty * - MACRO_NO_ARGS() if __VA_ARGS__ was empty * * @note In the future, we want to become compatible with clang. Hence, we provide two * versions of the following macros which are using variadic arguments. One is using the GNU extension ##__VA_ARGS__. * The other is using the C++20 feature __VA_OPT__(,). This allows users to compile their code with standard C++20 * enabled instead of the GNU extension. Below C++20, we haven't found any good alternative to using ##__VA_ARGS__. */ #if defined(__cplusplus) && (__cplusplus > 201703L) #define CHOOSE_MACRO_VA_ARG_INN_IMPL(...) __VA_OPT__(0) #define CHOOSE_MACRO_VA_ARG_INN(one, MACRO1, MACRO2, ...) MACRO1 #define CHOOSE_MACRO_VA_ARG(MACRO_WITH_ARGS, MACRO_WITH_NO_ARGS, ...) CHOOSE_MACRO_VA_ARG_INN(CHOOSE_MACRO_VA_ARG_INN_IMPL(__VA_ARGS__) __VA_OPT__(,) MACRO_WITH_ARGS, MACRO_WITH_NO_ARGS, 0) #else #define CHOOSE_MACRO_VA_ARG_INN(one, two, MACRO1, MACRO2, ...) MACRO1 #define CHOOSE_MACRO_VA_ARG(MACRO_WITH_ARGS, MACRO_WITH_NO_ARGS, ...) CHOOSE_MACRO_VA_ARG_INN(0, ##__VA_ARGS__, MACRO_WITH_ARGS, MACRO_WITH_NO_ARGS, 0) #endif /* Count number of arguments of __VA_ARGS__ * - reference https://groups.google.com/forum/#!topic/comp.std.c/d-6Mj5Lko_s * - __GET_NTH_ARG__() takes args >= N (64) but only expand to Nth one (64th) * - ESP_RSEQ_N() is reverse sequential to N to add padding to have Nth * position is the same as the number of arguments * - ##__VA_ARGS__ is used to deal with 0 parameter (swallows comma) */ #ifndef ESP_VA_NARG # define ESP_VA_NARG(...) ESP_NARG(_0, ##__VA_ARGS__, ESP_RSEQ_N()) # define ESP_NARG(...) ESP_GET_NTH_ARG(__VA_ARGS__) # define ESP_GET_NTH_ARG( \ _01,_02,_03,_04,_05,_06,_07,_08,_09,_10, \ _11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \ _21,_22,_23,_24,_25,_26,_27,_28,_29,_30, \ _31,_32,_33,_34,_35,_36,_37,_38,_39,_40, \ _41,_42,_43,_44,_45,_46,_47,_48,_49,_50, \ _51,_52,_53,_54,_55,_56,_57,_58,_59,_60, \ _61,_62,_63,N,...) N # define ESP_RSEQ_N() \ 62,61,60, \ 59,58,57,56,55,54,53,52,51,50, \ 49,48,47,46,45,44,43,42,41,40, \ 39,38,37,36,35,34,33,32,31,30, \ 29,28,27,26,25,24,23,22,21,20, \ 19,18,17,16,15,14,13,12,11,10, \ 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 #endif #ifndef ESP_UNUSED #define ESP_UNUSED(x) ((void)(x)) #endif #define ESP_INFINITE_LOOP() \ do { \ ESP_COMPILER_DIAGNOSTIC_PUSH_IGNORE("-Wanalyzer-infinite-loop") \ while(1); \ ESP_COMPILER_DIAGNOSTIC_POP("-Wanalyzer-infinite-loop") \ } while(1) #ifdef __cplusplus } #endif