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 C2UTILS_MACRO_UTILS_H_ 18 #define C2UTILS_MACRO_UTILS_H_ 19 20 /** \file 21 * Macro utilities for the utils library used by Codec2 implementations. 22 */ 23 24 /// \if 0 25 26 /* --------------------------------- VARIABLE ARGUMENT COUNTING --------------------------------- */ 27 28 // remove empty arguments - _C2_ARG() expands to '', while _C2_ARG(x) expands to ', x' 29 // _C2_ARGn(...) does the same for n arguments 30 #define _C2_ARG(...) , ##__VA_ARGS__ 31 #define _C2_ARG2(_1, _2) _C2_ARG(_1) _C2_ARG(_2) 32 #define _C2_ARG4(_1, _2, _3, _4) _C2_ARG2(_1, _2) _C2_ARG2(_3, _4) 33 #define _C2_ARG8(_1, _2, _3, _4, _5, _6, _7, _8) _C2_ARG4(_1, _2, _3, _4) _C2_ARG4(_5, _6, _7, _8) 34 #define _C2_ARG16(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16) \ 35 _C2_ARG8(_1, _2, _3, _4, _5, _6, _7, _8) _C2_ARG8(_9, _10, _11, _12, _13, _14, _15, _16) 36 37 // return the 65th argument 38 #define _C2_ARGC_3(_, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, \ 39 _17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32, \ 40 _33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48, \ 41 _49, _50, _51, _52, _53, _54, _55, _56, _57, _58, _59, _60, _61, _62, _63, _64, ...) _64 42 43 /// \endif 44 45 /** 46 * Returns the number of arguments. 47 */ 48 // We do this by prepending 1 and appending 65 designed values such that the 65th element 49 // will be the number of arguments. 50 #define _C2_ARGC(...) _C2_ARGC_1(0, ##__VA_ARGS__, \ 51 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, \ 52 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, \ 53 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) 54 55 /// \if 0 56 57 // step 1. remove empty arguments - this is needed to allow trailing comma in enum definitions 58 // (NOTE: we don't know which argument will have this trailing comma so we have to try all) 59 #define _C2_ARGC_1(_, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, \ 60 _17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32, \ 61 _33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48, \ 62 _49, _50, _51, _52, _53, _54, _55, _56, _57, _58, _59, _60, _61, _62, _63, _64, ...) \ 63 _C2_ARGC_2(_ _C2_ARG(_0) \ 64 _C2_ARG16(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16) \ 65 _C2_ARG16(_17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32) \ 66 _C2_ARG16(_33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48) \ 67 _C2_ARG16(_49, _50, _51, _52, _53, _54, _55, _56, _57, _58, _59, _60, _61, _62, _63, _64), \ 68 ##__VA_ARGS__) 69 70 // step 2. this is needed as removed arguments cannot be passed directly as empty into a macro 71 #define _C2_ARGC_2(...) _C2_ARGC_3(__VA_ARGS__) 72 73 /// \endif 74 75 /* -------------------------------- VARIABLE ARGUMENT CONVERSION -------------------------------- */ 76 77 /// \if 0 78 79 // macros that convert _1, _2, _3, ... to fn(_1, arg), fn(_2, arg), fn(_3, arg), ... 80 #define _C2_MAP_64(fn, arg, head, ...) fn(head, arg), _C2_MAP_63(fn, arg, ##__VA_ARGS__) 81 #define _C2_MAP_63(fn, arg, head, ...) fn(head, arg), _C2_MAP_62(fn, arg, ##__VA_ARGS__) 82 #define _C2_MAP_62(fn, arg, head, ...) fn(head, arg), _C2_MAP_61(fn, arg, ##__VA_ARGS__) 83 #define _C2_MAP_61(fn, arg, head, ...) fn(head, arg), _C2_MAP_60(fn, arg, ##__VA_ARGS__) 84 #define _C2_MAP_60(fn, arg, head, ...) fn(head, arg), _C2_MAP_59(fn, arg, ##__VA_ARGS__) 85 #define _C2_MAP_59(fn, arg, head, ...) fn(head, arg), _C2_MAP_58(fn, arg, ##__VA_ARGS__) 86 #define _C2_MAP_58(fn, arg, head, ...) fn(head, arg), _C2_MAP_57(fn, arg, ##__VA_ARGS__) 87 #define _C2_MAP_57(fn, arg, head, ...) fn(head, arg), _C2_MAP_56(fn, arg, ##__VA_ARGS__) 88 #define _C2_MAP_56(fn, arg, head, ...) fn(head, arg), _C2_MAP_55(fn, arg, ##__VA_ARGS__) 89 #define _C2_MAP_55(fn, arg, head, ...) fn(head, arg), _C2_MAP_54(fn, arg, ##__VA_ARGS__) 90 #define _C2_MAP_54(fn, arg, head, ...) fn(head, arg), _C2_MAP_53(fn, arg, ##__VA_ARGS__) 91 #define _C2_MAP_53(fn, arg, head, ...) fn(head, arg), _C2_MAP_52(fn, arg, ##__VA_ARGS__) 92 #define _C2_MAP_52(fn, arg, head, ...) fn(head, arg), _C2_MAP_51(fn, arg, ##__VA_ARGS__) 93 #define _C2_MAP_51(fn, arg, head, ...) fn(head, arg), _C2_MAP_50(fn, arg, ##__VA_ARGS__) 94 #define _C2_MAP_50(fn, arg, head, ...) fn(head, arg), _C2_MAP_49(fn, arg, ##__VA_ARGS__) 95 #define _C2_MAP_49(fn, arg, head, ...) fn(head, arg), _C2_MAP_48(fn, arg, ##__VA_ARGS__) 96 #define _C2_MAP_48(fn, arg, head, ...) fn(head, arg), _C2_MAP_47(fn, arg, ##__VA_ARGS__) 97 #define _C2_MAP_47(fn, arg, head, ...) fn(head, arg), _C2_MAP_46(fn, arg, ##__VA_ARGS__) 98 #define _C2_MAP_46(fn, arg, head, ...) fn(head, arg), _C2_MAP_45(fn, arg, ##__VA_ARGS__) 99 #define _C2_MAP_45(fn, arg, head, ...) fn(head, arg), _C2_MAP_44(fn, arg, ##__VA_ARGS__) 100 #define _C2_MAP_44(fn, arg, head, ...) fn(head, arg), _C2_MAP_43(fn, arg, ##__VA_ARGS__) 101 #define _C2_MAP_43(fn, arg, head, ...) fn(head, arg), _C2_MAP_42(fn, arg, ##__VA_ARGS__) 102 #define _C2_MAP_42(fn, arg, head, ...) fn(head, arg), _C2_MAP_41(fn, arg, ##__VA_ARGS__) 103 #define _C2_MAP_41(fn, arg, head, ...) fn(head, arg), _C2_MAP_40(fn, arg, ##__VA_ARGS__) 104 #define _C2_MAP_40(fn, arg, head, ...) fn(head, arg), _C2_MAP_39(fn, arg, ##__VA_ARGS__) 105 #define _C2_MAP_39(fn, arg, head, ...) fn(head, arg), _C2_MAP_38(fn, arg, ##__VA_ARGS__) 106 #define _C2_MAP_38(fn, arg, head, ...) fn(head, arg), _C2_MAP_37(fn, arg, ##__VA_ARGS__) 107 #define _C2_MAP_37(fn, arg, head, ...) fn(head, arg), _C2_MAP_36(fn, arg, ##__VA_ARGS__) 108 #define _C2_MAP_36(fn, arg, head, ...) fn(head, arg), _C2_MAP_35(fn, arg, ##__VA_ARGS__) 109 #define _C2_MAP_35(fn, arg, head, ...) fn(head, arg), _C2_MAP_34(fn, arg, ##__VA_ARGS__) 110 #define _C2_MAP_34(fn, arg, head, ...) fn(head, arg), _C2_MAP_33(fn, arg, ##__VA_ARGS__) 111 #define _C2_MAP_33(fn, arg, head, ...) fn(head, arg), _C2_MAP_32(fn, arg, ##__VA_ARGS__) 112 #define _C2_MAP_32(fn, arg, head, ...) fn(head, arg), _C2_MAP_31(fn, arg, ##__VA_ARGS__) 113 #define _C2_MAP_31(fn, arg, head, ...) fn(head, arg), _C2_MAP_30(fn, arg, ##__VA_ARGS__) 114 #define _C2_MAP_30(fn, arg, head, ...) fn(head, arg), _C2_MAP_29(fn, arg, ##__VA_ARGS__) 115 #define _C2_MAP_29(fn, arg, head, ...) fn(head, arg), _C2_MAP_28(fn, arg, ##__VA_ARGS__) 116 #define _C2_MAP_28(fn, arg, head, ...) fn(head, arg), _C2_MAP_27(fn, arg, ##__VA_ARGS__) 117 #define _C2_MAP_27(fn, arg, head, ...) fn(head, arg), _C2_MAP_26(fn, arg, ##__VA_ARGS__) 118 #define _C2_MAP_26(fn, arg, head, ...) fn(head, arg), _C2_MAP_25(fn, arg, ##__VA_ARGS__) 119 #define _C2_MAP_25(fn, arg, head, ...) fn(head, arg), _C2_MAP_24(fn, arg, ##__VA_ARGS__) 120 #define _C2_MAP_24(fn, arg, head, ...) fn(head, arg), _C2_MAP_23(fn, arg, ##__VA_ARGS__) 121 #define _C2_MAP_23(fn, arg, head, ...) fn(head, arg), _C2_MAP_22(fn, arg, ##__VA_ARGS__) 122 #define _C2_MAP_22(fn, arg, head, ...) fn(head, arg), _C2_MAP_21(fn, arg, ##__VA_ARGS__) 123 #define _C2_MAP_21(fn, arg, head, ...) fn(head, arg), _C2_MAP_20(fn, arg, ##__VA_ARGS__) 124 #define _C2_MAP_20(fn, arg, head, ...) fn(head, arg), _C2_MAP_19(fn, arg, ##__VA_ARGS__) 125 #define _C2_MAP_19(fn, arg, head, ...) fn(head, arg), _C2_MAP_18(fn, arg, ##__VA_ARGS__) 126 #define _C2_MAP_18(fn, arg, head, ...) fn(head, arg), _C2_MAP_17(fn, arg, ##__VA_ARGS__) 127 #define _C2_MAP_17(fn, arg, head, ...) fn(head, arg), _C2_MAP_16(fn, arg, ##__VA_ARGS__) 128 #define _C2_MAP_16(fn, arg, head, ...) fn(head, arg), _C2_MAP_15(fn, arg, ##__VA_ARGS__) 129 #define _C2_MAP_15(fn, arg, head, ...) fn(head, arg), _C2_MAP_14(fn, arg, ##__VA_ARGS__) 130 #define _C2_MAP_14(fn, arg, head, ...) fn(head, arg), _C2_MAP_13(fn, arg, ##__VA_ARGS__) 131 #define _C2_MAP_13(fn, arg, head, ...) fn(head, arg), _C2_MAP_12(fn, arg, ##__VA_ARGS__) 132 #define _C2_MAP_12(fn, arg, head, ...) fn(head, arg), _C2_MAP_11(fn, arg, ##__VA_ARGS__) 133 #define _C2_MAP_11(fn, arg, head, ...) fn(head, arg), _C2_MAP_10(fn, arg, ##__VA_ARGS__) 134 #define _C2_MAP_10(fn, arg, head, ...) fn(head, arg), _C2_MAP_9(fn, arg, ##__VA_ARGS__) 135 #define _C2_MAP_9(fn, arg, head, ...) fn(head, arg), _C2_MAP_8(fn, arg, ##__VA_ARGS__) 136 #define _C2_MAP_8(fn, arg, head, ...) fn(head, arg), _C2_MAP_7(fn, arg, ##__VA_ARGS__) 137 #define _C2_MAP_7(fn, arg, head, ...) fn(head, arg), _C2_MAP_6(fn, arg, ##__VA_ARGS__) 138 #define _C2_MAP_6(fn, arg, head, ...) fn(head, arg), _C2_MAP_5(fn, arg, ##__VA_ARGS__) 139 #define _C2_MAP_5(fn, arg, head, ...) fn(head, arg), _C2_MAP_4(fn, arg, ##__VA_ARGS__) 140 #define _C2_MAP_4(fn, arg, head, ...) fn(head, arg), _C2_MAP_3(fn, arg, ##__VA_ARGS__) 141 #define _C2_MAP_3(fn, arg, head, ...) fn(head, arg), _C2_MAP_2(fn, arg, ##__VA_ARGS__) 142 #define _C2_MAP_2(fn, arg, head, ...) fn(head, arg), _C2_MAP_1(fn, arg, ##__VA_ARGS__) 143 #define _C2_MAP_1(fn, arg, head, ...) fn(head, arg) 144 145 /// \endif 146 147 /** 148 * Maps each argument using another macro x -> fn(x, arg) 149 */ 150 // use wrapper to call the proper mapper based on the number of arguments 151 #define _C2_MAP(fn, arg, ...) _C2_MAP__(_C2_ARGC(__VA_ARGS__), fn, arg, ##__VA_ARGS__) 152 153 /// \if 0 154 155 // evaluate _n so it becomes a number 156 #define _C2_MAP__(_n, fn, arg, ...) _C2_MAP_(_n, fn, arg, __VA_ARGS__) 157 // call the proper mapper 158 #define _C2_MAP_(_n, fn, arg, ...) _C2_MAP_##_n (fn, arg, __VA_ARGS__) 159 160 /// \endif 161 162 #endif // C2UTILS_MACRO_UTILS_H_ 163