/* Kaleidoscope - Firmware for computer input devices * Copyright (C) 2013-2018 Keyboard.io, Inc. * * This program is free software: you can redistribute it and/or modify it under * the terms of the GNU General Public License as published by the Free Software * Foundation, version 3. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more * details. * * You should have received a copy of the GNU General Public License along with * this program. If not, see . */ #pragma once // Code generated by muli-line pre-processor macros is hard to read after // pre-processing. // // When you want to check pre-processed code, e.g. for debugging or // to understand what's going on, do the following: // // 1) Add the compiler command line definition // -DKALEIDOSCOPE_ENABLE_MACRO_NEWLINE_SUBSTITUTION // This prevents the __NL__ macro being defined below. // 2) Generate the preprocessed code (it will contain a lot of __NL__ definitions). // 3) Open the pre-processed code in your favorite editor. // 3.1) Replace all __NL__ with newline characters. // In vim the command would be ':%s/__NL__/\r/g'. // 3.2) Autocorrect code-indenting to improve readability. This is necessary // as pre-processor macros remove all whitespaces at the beginning of lines. // With vim, the command gg=G helps (just type the characters one after // the other). // 4) Don't forget to remove the // -DKALEIDOSCOPE_ENABLE_MACRO_NEWLINE_SUBSTITUTION // from your compiler command line. Else the code won't compile. #ifndef KALEIDOSCOPE_ENABLE_MACRO_NEWLINE_SUBSTITUTION #define __NL__ #endif #define __NN__ // Some auxiliary macros // #define __STRINGIZE(S) #S #define STRINGIZE(S) __STRINGIZE(S) // Allow for the creation of verbose messages in static_asserts // #define VERBOSE_STATIC_ASSERT_HEADER \ "\n" __NL__ \ "\n***************************************************************" __NL__ \ "\n******************** READ THIS CAREFULLY! *********************" __NL__ \ "\n***************************************************************" __NL__ \ "\n" #define VERBOSE_STATIC_ASSERT_FOOTER \ "\n" __NL__ \ "\n***************************************************************" __NL__ \ "\n***************************************************************" __NL__ \ "\n***************************************************************" __NL__ \ "\n" #define VERBOSE_FILE_INFO \ "\nFile: " __FILE__ __NL__ #define VERBOSE_LINE_INFO \ "\nLine: " STRINGIZE(__LINE__) __NL__ // The macro function RESTRICT_ARGS_COUNT can be used to generate more // verbose error messages when users supply an insuitable number of arguments // to a macro. // // For a macro it is used wherever one of the arguments A, B, C might // be used, e.g. // #if 0 // This is just so that A_MACRO is not actually defined #define A_MACRO(A, B, C, ...) \ (void)RESTRICT_ARGS_COUNT(0, 3, A_MACRO, ##__VA_ARGS__); \ int a = A; \ int b = B; \ int c = C; #endif // // Note that RESTRICT_ARGS_COUNT can also be invoked wherever one of the macro // arguments is used, e.g. // #if 0 // This is just so that B_MACRO is not actually defined #define B_MACRO(A, B, C, ...) int array[] = { A, B, RESTRICT_ARGS_COUNT(C, 3, B_MACRO, ##__VA_ARGS__) }; #endif // #define RESTRICT_ARGS_COUNT(B, \ NUM_EXPECTED_ARGS, \ ORIGINAL_MACRO, \ ...) \ ((struct { __NL__ \ /* Here we are in the body of a dummy lambda function. */ __NL__ \ /* []{} is, BTW, the shortest way to write a lambda. */ __NL__ \ /* It is only used to hold the static_assert that cannot be */ __NL__ \ /* defined directly in the keymap initializer list. By using the */ __NL__ \ /* comma operator ((A, B) always evaluates to b), we ensure */ __NL__ \ /* that not the lambda but B is what ASSERT_ARGS_COUNT */ __NL__ \ /* finally evaluates to. */ __NL__ \ /* Please not that passing B through this macro is a must */ __NL__ \ /* as we need it for the comma operator to work. */ __NL__ \ static_assert(sizeof(const char) == sizeof(#__VA_ARGS__ ), __NL__ \ /* sizeof(const char) == sizeof(#__VA_ARGS__ ) checks the quoted */ __NL__ \ /* list of additional arguments. If there are none, then the */ __NL__ \ /* length of #__VA_ARGS__ is a single char as it contains '\0'. */ __NL__ \ /* This check is not able to find the corner case of a single */ __NL__ \ /* superfluous comma at the end of the macro arguments as this */ __NL__ \ /* causes #__VA_ARGS__ being empty (only '\0'). */ __NL__ \ VERBOSE_STATIC_ASSERT_HEADER __NL__ \ __NL__ \ VERBOSE_FILE_INFO __NL__ \ VERBOSE_LINE_INFO __NL__ \ "\n" __NL__ \ "\nStrange arguments found in invocation of " #ORIGINAL_MACRO "." __NL__ \ "\n" __NL__ \ "\nPlease make sure to pass exactly " #NUM_EXPECTED_ARGS __NL__ \ " macro arguments to" __NL__ \ "\n" #ORIGINAL_MACRO ". Also make sure that there are no dangling" __NL__ \ "\ncommas at the end of the argument list." __NL__ \ "\n" __NL__ \ "\nThis is the superfluous part at the end of the macro" __NL__ \ "\narguments list: \'" #__VA_ARGS__ "\'" __NL__ \ __NL__ \ VERBOSE_STATIC_ASSERT_FOOTER __NL__ \ ); __NL__ \ __NL__ \ }){}, /* End of dummy lambda, the comma operator's A operand. */ __NL__ \ B /* The overall ASSERT_ARGS_COUNT evaluates to B. */ __NL__ \ )