diff --git a/include/nlohmann/detail/view/builder.hpp b/include/nlohmann/detail/view/builder.hpp index 1cd01fef6..5ce68220d 100644 --- a/include/nlohmann/detail/view/builder.hpp +++ b/include/nlohmann/detail/view/builder.hpp @@ -801,7 +801,10 @@ indent_done: n->flags = flags; n->extra = extra; n->off = static_cast(off); - set_integer_bits(*n, second); + // len is the low half of the second word, next the high half + // (not a native word over both, which swaps them on big-endian) + n->len = static_cast(second); + n->next = static_cast(second >> 32); #endif return n; } diff --git a/include/nlohmann/detail/view/node.hpp b/include/nlohmann/detail/view/node.hpp index 471c1f844..5818066ae 100644 --- a/include/nlohmann/detail/view/node.hpp +++ b/include/nlohmann/detail/view/node.hpp @@ -57,17 +57,27 @@ NLOHMANN_VIEW_ALWAYS_INLINE bool is_container(const node& n) noexcept return static_cast(n.kind) - 1u <= 1u; } -/// the converted value of an integer node (stored in len/next) +/// the converted value of an integer node: len is its low half, next its high +/// half (on little-endian targets the two words are the value in memory) NLOHMANN_VIEW_ALWAYS_INLINE std::uint64_t integer_bits(const node& n) noexcept { +#if NLOHMANN_VIEW_LITTLE_ENDIAN std::uint64_t v = 0; std::memcpy(&v, reinterpret_cast(&n) + 8, 8); // NOLINT(cppcoreguidelines-pro-type-reinterpret-cast) return v; +#else + return static_cast(n.len) | (static_cast(n.next) << 32); +#endif } NLOHMANN_VIEW_ALWAYS_INLINE void set_integer_bits(node& n, std::uint64_t v) noexcept { +#if NLOHMANN_VIEW_LITTLE_ENDIAN std::memcpy(reinterpret_cast(&n) + 8, &v, 8); // NOLINT(cppcoreguidelines-pro-type-reinterpret-cast) +#else + n.len = static_cast(v); + n.next = static_cast(v >> 32); +#endif } /// token length of a number node diff --git a/tests/src/unit-json_view_builder.cpp b/tests/src/unit-json_view_builder.cpp index 9d3ea943b..c585eb919 100644 --- a/tests/src/unit-json_view_builder.cpp +++ b/tests/src/unit-json_view_builder.cpp @@ -401,3 +401,61 @@ TEST_CASE("json_view builder") } } } + +TEST_CASE("json_view node integer bits") +{ + using nlohmann::detail::view::integer_bits; + using nlohmann::detail::view::set_integer_bits; + + // an integer lives in len (low half) and next (high half), on any byte + // order; a big-endian target must not store the native word over both + SECTION("set_integer_bits and integer_bits") + { + node n = {}; + for (const std::uint64_t v : + { + std::uint64_t{0}, std::uint64_t{1}, std::uint64_t{0xFFFFFFFFu}, std::uint64_t{0x100000000u}, + std::uint64_t{0x0000000200000003u}, std::uint64_t{0x0123456789ABCDEFu}, std::uint64_t{0xFFFFFFFFFFFFFFFEu} + }) + { + CAPTURE(v) + n.kind = 0x5A; + n.flags = 0xA5; + n.extra = 0x1234; + n.off = 0x89ABCDEFu; + set_integer_bits(n, v); + CHECK(integer_bits(n) == v); + CHECK(n.len == static_cast(v)); + CHECK(n.next == static_cast(v >> 32)); + // the other fields are untouched + CHECK(n.kind == 0x5A); + CHECK(n.flags == 0xA5); + CHECK(n.extra == 0x1234); + CHECK(n.off == 0x89ABCDEFu); + } + } + + SECTION("parsed integers") + { + struct integer_case + { + const char* text; + std::uint64_t bits; + }; + for (const integer_case c : + { + integer_case{"[8589934595]", 0x0000000200000003u}, integer_case{"[4294967296]", 0x100000000u}, integer_case{"[4294967295]", 0xFFFFFFFFu}, + integer_case{"[-2]", 0xFFFFFFFFFFFFFFFEu}, integer_case{"[-4294967297]", 0xFFFFFFFEFFFFFFFFu}, integer_case{"[18446744073709551615]", 0xFFFFFFFFFFFFFFFFu}, + integer_case{"[7]", 7u} + }) + { + CAPTURE(c.text) + const built b = build(c.text, false, false, true); + REQUIRE(b.ok); + const node& n = b.data->tape[1]; + CHECK(integer_bits(n) == c.bits); + CHECK(n.len == static_cast(c.bits)); + CHECK(n.next == static_cast(c.bits >> 32)); + } + } +}