mhd_bool.m4 (5430B)
1 # SYNOPSIS 2 # 3 # MHD_BOOL 4 # 5 # DESCRIPTION 6 # 7 # This macro checks whether the boolean keywords "bool", "true", "false" 8 # are supported by compiler. If they are not supported, suitable replacement 9 # macros are defined. 10 # 11 # Example usage: 12 # 13 # MHD_BOOL 14 # 15 # The cache variables are used in the checks so if any test will not work 16 # correctly on some platform, user may simply fix it by giving cache 17 # variable in configure parameters, for example: 18 # 19 # ./configure mhd_cv_bool_native=no 20 # 21 # This simplify building from source on exotic platforms as patching 22 # of configure.ac is not required to change results of tests. 23 # 24 # LICENSE 25 # 26 # Copyright (c) 2024 Karlson2k (Evgeny Grin) <k2k@narod.ru> 27 # 28 # Copying and distribution of this file, with or without modification, are 29 # permitted in any medium without royalty provided the copyright notice 30 # and this notice are preserved. This file is offered as-is, without any 31 # warranty. 32 33 #serial 2 34 35 AC_DEFUN([MHD_BOOL],[dnl 36 AC_PREREQ([2.64])dnl for AS_VAR_IF 37 m4_newline([[# Expansion of macro $0 starts here]]) 38 AC_LANG_ASSERT([C])dnl 39 AC_REQUIRE([AC_PROG_CC])dnl 40 AH_TEMPLATE([[HAVE_STDBOOL_H]], [Define to 1 i][f you have the <stdbool.h> header file and <stdbool.h> is required to use 'bool' type.])dnl 41 AH_TEMPLATE([[HAVE_BUILTIN_TYPE_BOOL]], [Define to 1 i][f you have the boolean type that takes only 'true' and 'false'.])dnl 42 AH_TEMPLATE([[bool]], [Define to the name of the type which is used as a replacemnt f][or boolean type.])dnl 43 [mhd_bool_test_code=' 44 static bool get_false(void) 45 { 46 static bool test_arr[sizeof(bool)*2 - 1] = {false}; 47 return test_arr[0]; 48 } 49 50 int main(void) 51 { 52 static bool var1 = true; 53 static bool var2 = false; 54 static int int_arr[2 - 3 * ((int) (false))] = {(int) true, (int) false}; 55 static bool bool_arr[2 - 3 * ((int) (!true))] = {false, true}; 56 i][f(!var1 || var2 || !int_arr[0] || int_arr[1] || bool_arr[0] || 57 !bool_arr[1] || get_false() || 0 == sizeof(bool) || false || !true) 58 return 5; 59 return 0; 60 } 61 '] 62 AC_CACHE_CHECK([[whether "bool", "true" and "false" work natively]],[[mhd_cv_bool_native]], 63 [AC_COMPILE_IFELSE([AC_LANG_SOURCE([[${mhd_bool_test_code}]])],[mhd_cv_bool_native="yes"], 64 [mhd_cv_bool_native="no"])dnl AC_COMPILE_IFELSE 65 ]) 66 AS_VAR_IF([mhd_cv_bool_native],["yes"],[ 67 AC_DEFINE([[HAVE_BUILTIN_TYPE_BOOL]],[1])],[dnl mhd_cv_bool_native "yes" 68 AC_CACHE_CHECK([[whether <stdbool.h> is present and defines proper "bool", "true" and "false"]],[[mhd_cv_bool_stdbool]], 69 [AC_COMPILE_IFELSE([AC_LANG_SOURCE([[ 70 #include <stdbool.h> 71 72 ${mhd_bool_test_code} 73 ]])],[mhd_cv_bool_stdbool="yes"],[mhd_cv_bool_stdbool="no"])dnl AC_COMPILE_IFELSE 74 ]) 75 dnl end of AC_CACHE_CHECK 76 AS_VAR_IF([mhd_cv_bool_stdbool],["yes"],[ 77 AC_DEFINE([[HAVE_STDBOOL_H]],[1]) 78 AC_DEFINE([[HAVE_BUILTIN_TYPE_BOOL]],[1])],[dnl mhd_cv_bool_stdbool "yes" 79 # Need 'bool', 'false' and 'true'. 80 AC_CHECK_TYPE([bool],[AC_DEFINE([[HAVE_BUILTIN_TYPE_BOOL]], [[1]])],[dnl AC_CHECK_TYPE bool 81 AC_CHECK_TYPE([_Bool],[AC_DEFINE([[HAVE_BUILTIN_TYPE_BOOL]], [[1]]) 82 AC_DEFINE([[bool]], [[_Bool]])],[AC_DEFINE([[bool]], [[int]]) 83 ],[[]])dnl AC_CHECK_TYPE _Bool 84 ],[[]])dnl AC_CHECK_TYPE bool 85 # Have 'bool'. Need 'false' and 'true'. 86 AC_CACHE_CHECK([[whether "false" keyword available and works]],[[mhd_cv_keyword_false_works]], 87 [AC_COMPILE_IFELSE([AC_LANG_SOURCE([[ 88 int main(void) 89 { 90 static bool var1 = false || false; 91 static bool var2 = false; 92 static bool bool_arr[2 - 3 * ((int) (false))] = {false, !false}; 93 i][f(var1 || var2 || bool_arr[0] || !bool_arr[1] || false) 94 return 5; 95 return 0; 96 } 97 ]])], [[mhd_cv_keyword_false_works='yes']], [[mhd_cv_keyword_false_works='no']])]) 98 dnl end of AC_CACHE_CHECK 99 AS_VAR_IF([[mhd_cv_keyword_false_works]], [["no"]],[dnl 100 AC_DEFINE([[false]],[[(0)]], [Define to value interpreted by compiler as boolean "false", i][f "false" is not a keyword and not defined by headers.])]) 101 dnl AS_VAR_IF mhd_cv_keyword_false_works 102 # Have 'bool' and 'false'. Need 'true'. 103 AC_CACHE_CHECK([[whether "true" keyword available and works]],[[mhd_cv_keyword_true_works]], 104 [AC_COMPILE_IFELSE([AC_LANG_SOURCE([[ 105 int main(void) 106 { 107 static bool var1 = true && true; 108 static bool var2 = true; 109 static bool bool_arr[2 - 3 * ((int) (!true))] = {true, !true}; 110 i][f(!var1 || !var2 || !bool_arr[0] || bool_arr[1] || !true) 111 return 5; 112 return 0; 113 } 114 ]])], [[mhd_cv_keyword_true_works='yes']], [[mhd_cv_keyword_true_works='no']])]) 115 dnl end of AC_CACHE_CHECK 116 AS_VAR_IF([[mhd_cv_keyword_true_works]], [["no"]],[dnl 117 AC_DEFINE([[true]],[[(!false)]], [Define to value interpreted by compiler as boolean "true", i][f "true" is not a keyword and not defined by headers.])]) 118 dnl AS_VAR_IF mhd_cv_keyword_false_works 119 # Have 'bool', 'false' and 'true'. 120 AC_CACHE_CHECK([[whether the defined "bool", "true" and "false" can work together]],[[mhd_cv_bool_true_false_work]], 121 [AC_COMPILE_IFELSE([AC_LANG_SOURCE([[${mhd_bool_test_code}]])],[mhd_cv_bool_true_false_work="yes"], 122 [mhd_cv_bool_true_false_work="no"])dnl AC_COMPILE_IFELSE 123 ]) 124 dnl end of AC_CACHE_CHECK 125 AS_VAR_IF([[mhd_cv_bool_true_false_work]], [["yes"]],[[:]],[dnl 126 AC_MSG_FAILURE([cannot find suitable replacements for "bool", "true" and "false"]) 127 ]) 128 dnl end of AS_VAR_IF mhd_cv_bool_true_false_work "yes" 129 ]) 130 dnl end of AS_VAR_IF mhd_cv_bool_stdbool "yes" 131 ]) 132 dnl end of AS_VAR_IF mhd_cv_bool_native "yes" 133 AS_UNSET([mhd_bool_test_code]) 134 m4_newline([[# Expansion of macro $0 ends here]]) 135 ])dnl AC_DEFUN MHD_BOOL