From c0d8921a6797497f3fbd2a8c2a2b29aaca9704c3 Mon Sep 17 00:00:00 2001
From: Julian Becker <becker.julian@gmail.com>
Date: Sat, 15 Sep 2018 12:00:53 +0200
Subject: [PATCH] BSON: support objects with int64 members

---
 .../nlohmann/detail/input/binary_reader.hpp   | 10 ++++++
 .../nlohmann/detail/output/binary_writer.hpp  | 26 ++++++++++----
 single_include/nlohmann/json.hpp              | 36 +++++++++++++++----
 test/src/unit-bson.cpp                        | 23 ++++++++++++
 4 files changed, 83 insertions(+), 12 deletions(-)

diff --git a/include/nlohmann/detail/input/binary_reader.hpp b/include/nlohmann/detail/input/binary_reader.hpp
index f11e164e..d135a4c2 100644
--- a/include/nlohmann/detail/input/binary_reader.hpp
+++ b/include/nlohmann/detail/input/binary_reader.hpp
@@ -213,6 +213,16 @@ class binary_reader
                     sax->number_integer(static_cast<std::int32_t>(value));
                 }
                 break;
+                case 0x12: // int64
+                {
+                    string_t key;
+                    get_bson_cstr(key);
+                    sax->key(key);
+                    std::int64_t value;
+                    get_number_little_endian(value);
+                    sax->number_integer(static_cast<std::int64_t>(value));
+                }
+                break;
                 case 0x0A: // null
                 {
                     string_t key;
diff --git a/include/nlohmann/detail/output/binary_writer.hpp b/include/nlohmann/detail/output/binary_writer.hpp
index ed59b7c2..24426d48 100644
--- a/include/nlohmann/detail/output/binary_writer.hpp
+++ b/include/nlohmann/detail/output/binary_writer.hpp
@@ -723,14 +723,28 @@ class binary_writer
 
     std::size_t write_bson_integer(const typename BasicJsonType::string_t& name, const BasicJsonType& j)
     {
-        oa->write_character(static_cast<CharType>(0x10)); // int32
-        oa->write_characters(
-            reinterpret_cast<const CharType*>(name.c_str()),
-            name.size() + 1u);
+        if (j.m_value.number_integer <= static_cast<uint64_t>((std::numeric_limits<int32_t>::max)()))
+        {
+            oa->write_character(static_cast<CharType>(0x10)); // int32
+            oa->write_characters(
+                reinterpret_cast<const CharType*>(name.c_str()),
+                name.size() + 1u);
 
-        write_number_little_endian(static_cast<std::int32_t>(j.m_value.number_integer));
+            write_number_little_endian(static_cast<std::int32_t>(j.m_value.number_integer));
 
-        return /*id*/ 1ul + name.size() + 1ul + sizeof(std::int32_t);
+            return /*id*/ 1ul + name.size() + 1ul + sizeof(std::int32_t);
+        }
+        else
+        {
+            oa->write_character(static_cast<CharType>(0x12)); // int64
+            oa->write_characters(
+                reinterpret_cast<const CharType*>(name.c_str()),
+                name.size() + 1u);
+
+            write_number_little_endian(static_cast<std::int64_t>(j.m_value.number_integer));
+
+            return /*id*/ 1ul + name.size() + 1ul + sizeof(std::int64_t);
+        }
     }
 
     std::size_t write_bson_object_entry(const typename BasicJsonType::string_t& name, const BasicJsonType& j)
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index d0cce8a1..c564e57f 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -6197,6 +6197,16 @@ class binary_reader
                     sax->number_integer(static_cast<std::int32_t>(value));
                 }
                 break;
+                case 0x12: // int64
+                {
+                    string_t key;
+                    get_bson_cstr(key);
+                    sax->key(key);
+                    std::int64_t value;
+                    get_number_little_endian(value);
+                    sax->number_integer(static_cast<std::int64_t>(value));
+                }
+                break;
                 case 0x0A: // null
                 {
                     string_t key;
@@ -8547,14 +8557,28 @@ class binary_writer
 
     std::size_t write_bson_integer(const typename BasicJsonType::string_t& name, const BasicJsonType& j)
     {
-        oa->write_character(static_cast<CharType>(0x10)); // int32
-        oa->write_characters(
-            reinterpret_cast<const CharType*>(name.c_str()),
-            name.size() + 1u);
+        if (j.m_value.number_integer <= static_cast<uint64_t>((std::numeric_limits<int32_t>::max)()))
+        {
+            oa->write_character(static_cast<CharType>(0x10)); // int32
+            oa->write_characters(
+                reinterpret_cast<const CharType*>(name.c_str()),
+                name.size() + 1u);
 
-        write_number_little_endian(static_cast<std::int32_t>(j.m_value.number_integer));
+            write_number_little_endian(static_cast<std::int32_t>(j.m_value.number_integer));
 
-        return /*id*/ 1ul + name.size() + 1ul + sizeof(std::int32_t);
+            return /*id*/ 1ul + name.size() + 1ul + sizeof(std::int32_t);
+        }
+        else
+        {
+            oa->write_character(static_cast<CharType>(0x12)); // int64
+            oa->write_characters(
+                reinterpret_cast<const CharType*>(name.c_str()),
+                name.size() + 1u);
+
+            write_number_little_endian(static_cast<std::int64_t>(j.m_value.number_integer));
+
+            return /*id*/ 1ul + name.size() + 1ul + sizeof(std::int64_t);
+        }
     }
 
     std::size_t write_bson_object_entry(const typename BasicJsonType::string_t& name, const BasicJsonType& j)
diff --git a/test/src/unit-bson.cpp b/test/src/unit-bson.cpp
index 266dd12a..73989769 100644
--- a/test/src/unit-bson.cpp
+++ b/test/src/unit-bson.cpp
@@ -255,6 +255,29 @@ TEST_CASE("BSON")
             CHECK(json::from_bson(result, true, false) == j);
         }
 
+        SECTION("non-empty object with integer (64-bit) member")
+        {
+            json j =
+            {
+                { "entry", std::int64_t{0x1234567804030201} }
+            };
+
+            std::vector<uint8_t> expected =
+            {
+                0x14, 0x00, 0x00, 0x00, // size (little endian)
+                0x12, /// entry: int64
+                'e', 'n', 't', 'r', 'y', '\x00',
+                0x01, 0x02, 0x03, 0x04, 0x78, 0x56, 0x34, 0x12,
+                0x00 // end marker
+            };
+
+            const auto result = json::to_bson(j);
+            CHECK(result == expected);
+
+            // roundtrip
+            CHECK(json::from_bson(result) == j);
+            CHECK(json::from_bson(result, true, false) == j);
+        }
 
     }
 }