/* * Copyright 2022 MongoDB, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include #ifndef BSON_CMP_H #define BSON_CMP_H #include /* ssize_t */ #include /* BSON_CONCAT */ #include #include #include BSON_BEGIN_DECLS /* Based on the "Safe Integral Comparisons" proposal merged in C++20: * http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2020/p0586r2.html * * Due to lack of type deduction in C, relational comparison functions (e.g. * `cmp_less`) are defined in sets of four "functions" according to the * signedness of each value argument, e.g.: * - bson_cmp_less_ss (signed-value, signed-value) * - bson_cmp_less_uu (unsigned-value, unsigned-value) * - bson_cmp_less_su (signed-value, unsigned-value) * - bson_cmp_less_us (unsigned-value, signed-value) * * Similarly, the `in_range` function is defined as a set of two "functions" * according to the signedness of the value argument: * - bson_in_range_signed (Type, signed-value) * - bson_in_range_unsigned (Type, unsigned-value) * * The user must take care to use the correct signedness for the provided * argument(s). Enabling compiler warnings for implicit sign conversions is * recommended. */ #define BSON_CMP_SET(op, ss, uu, su, us) \ static BSON_INLINE bool BSON_CONCAT3 (bson_cmp_, op, _ss) (int64_t t, \ int64_t u) \ { \ return (ss); \ } \ \ static BSON_INLINE bool BSON_CONCAT3 (bson_cmp_, op, _uu) (uint64_t t, \ uint64_t u) \ { \ return (uu); \ } \ \ static BSON_INLINE bool BSON_CONCAT3 (bson_cmp_, op, _su) (int64_t t, \ uint64_t u) \ { \ return (su); \ } \ \ static BSON_INLINE bool BSON_CONCAT3 (bson_cmp_, op, _us) (uint64_t t, \ int64_t u) \ { \ return (us); \ } BSON_CMP_SET (equal, t == u, t == u, t < 0 ? false : (uint64_t) (t) == u, u < 0 ? false : t == (uint64_t) (u)) BSON_CMP_SET (not_equal, !bson_cmp_equal_ss (t, u), !bson_cmp_equal_uu (t, u), !bson_cmp_equal_su (t, u), !bson_cmp_equal_us (t, u)) BSON_CMP_SET (less, t < u, t < u, t < 0 ? true : (uint64_t) (t) < u, u < 0 ? false : t < (uint64_t) (u)) BSON_CMP_SET (greater, bson_cmp_less_ss (u, t), bson_cmp_less_uu (u, t), bson_cmp_less_us (u, t), bson_cmp_less_su (u, t)) BSON_CMP_SET (less_equal, !bson_cmp_greater_ss (t, u), !bson_cmp_greater_uu (t, u), !bson_cmp_greater_su (t, u), !bson_cmp_greater_us (t, u)) BSON_CMP_SET (greater_equal, !bson_cmp_less_ss (t, u), !bson_cmp_less_uu (t, u), !bson_cmp_less_su (t, u), !bson_cmp_less_us (t, u)) #undef BSON_CMP_SET /* Return true if the given value is within the range of the corresponding * signed type. The suffix must match the signedness of the given value. */ #define BSON_IN_RANGE_SET_SIGNED(Type, min, max) \ static BSON_INLINE bool BSON_CONCAT3 (bson_in_range, _##Type, _signed) ( \ int64_t value) \ { \ return bson_cmp_greater_equal_ss (value, min) && \ bson_cmp_less_equal_ss (value, max); \ } \ \ static BSON_INLINE bool BSON_CONCAT3 (bson_in_range, _##Type, _unsigned) ( \ uint64_t value) \ { \ return bson_cmp_greater_equal_us (value, min) && \ bson_cmp_less_equal_us (value, max); \ } /* Return true if the given value is within the range of the corresponding * unsigned type. The suffix must match the signedness of the given value. */ #define BSON_IN_RANGE_SET_UNSIGNED(Type, max) \ static BSON_INLINE bool BSON_CONCAT3 (bson_in_range, _##Type, _signed) ( \ int64_t value) \ { \ return bson_cmp_greater_equal_su (value, 0u) && \ bson_cmp_less_equal_su (value, max); \ } \ \ static BSON_INLINE bool BSON_CONCAT3 (bson_in_range, _##Type, _unsigned) ( \ uint64_t value) \ { \ return bson_cmp_less_equal_uu (value, max); \ } BSON_IN_RANGE_SET_SIGNED (signed_char, SCHAR_MIN, SCHAR_MAX) BSON_IN_RANGE_SET_SIGNED (short, SHRT_MIN, SHRT_MAX) BSON_IN_RANGE_SET_SIGNED (int, INT_MIN, INT_MAX) BSON_IN_RANGE_SET_SIGNED (long, LONG_MIN, LONG_MAX) BSON_IN_RANGE_SET_SIGNED (long_long, LLONG_MIN, LLONG_MAX) BSON_IN_RANGE_SET_UNSIGNED (unsigned_char, UCHAR_MAX) BSON_IN_RANGE_SET_UNSIGNED (unsigned_short, USHRT_MAX) BSON_IN_RANGE_SET_UNSIGNED (unsigned_int, UINT_MAX) BSON_IN_RANGE_SET_UNSIGNED (unsigned_long, ULONG_MAX) BSON_IN_RANGE_SET_UNSIGNED (unsigned_long_long, ULLONG_MAX) BSON_IN_RANGE_SET_SIGNED (int8_t, INT8_MIN, INT8_MAX) BSON_IN_RANGE_SET_SIGNED (int16_t, INT16_MIN, INT16_MAX) BSON_IN_RANGE_SET_SIGNED (int32_t, INT32_MIN, INT32_MAX) BSON_IN_RANGE_SET_SIGNED (int64_t, INT64_MIN, INT64_MAX) BSON_IN_RANGE_SET_UNSIGNED (uint8_t, UINT8_MAX) BSON_IN_RANGE_SET_UNSIGNED (uint16_t, UINT16_MAX) BSON_IN_RANGE_SET_UNSIGNED (uint32_t, UINT32_MAX) BSON_IN_RANGE_SET_UNSIGNED (uint64_t, UINT64_MAX) BSON_IN_RANGE_SET_SIGNED (ssize_t, SSIZE_MIN, SSIZE_MAX) BSON_IN_RANGE_SET_UNSIGNED (size_t, SIZE_MAX) #undef BSON_IN_RANGE_SET_SIGNED #undef BSON_IN_RANGE_SET_UNSIGNED /* Return true if the value with *signed* type is in the representable range of * Type and false otherwise. */ #define bson_in_range_signed(Type, value) \ BSON_CONCAT3 (bson_in_range, _##Type, _signed) (value) /* Return true if the value with *unsigned* type is in the representable range * of Type and false otherwise. */ #define bson_in_range_unsigned(Type, value) \ BSON_CONCAT3 (bson_in_range, _##Type, _unsigned) (value) BSON_END_DECLS #endif /* BSON_CMP_H */