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eramongodberamongodb
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Add safe integral comparison functions
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‎src/libbson/CMakeLists.txt

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@@ -181,6 +181,7 @@ set (HEADERS
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${PROJECT_SOURCE_DIR}/src/bson/bcon.h
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${PROJECT_SOURCE_DIR}/src/bson/bson-atomic.h
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${PROJECT_SOURCE_DIR}/src/bson/bson-clock.h
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${PROJECT_SOURCE_DIR}/src/bson/bson-cmp.h
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${PROJECT_SOURCE_DIR}/src/bson/bson-compat.h
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${PROJECT_SOURCE_DIR}/src/bson/bson-context.h
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${PROJECT_SOURCE_DIR}/src/bson/bson-decimal128.h

‎src/libbson/src/bson/CMakeLists.txt

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@@ -16,6 +16,7 @@ set (src_libbson_src_bson_DIST_hs
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bson-memory.h
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bson-oid.h
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bson-reader.h
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bson-cmp.h
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bson-string.h
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bson-types.h
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bson-utf8.h

‎src/libbson/src/bson/bson-cmp.h

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

‎src/libbson/src/bson/bson.h

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#include "bson-macros.h"
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#include "bson-config.h"
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#include "bson-atomic.h"
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#include "bson-cmp.h"
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#include "bson-context.h"
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#include "bson-clock.h"
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#include "bson-decimal128.h"

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