I using bson_json_reader_read() in my service to convert JSON string to BSON data.
But if the JSON string has defective in MongoDB extended JSON fields, the function bson_json_reader_read() will crash rather than return error.

These are three cases:
---------------------
case 1
---------------------
JSON string: {"$date" : { "$numberLong" : "1455853006123"}}

screen output:
src/bson/bson.c:1607 bson_append_date_time(): precondition failed: key

crashed service stack by gdb:
---------------------
#0 0x00007ffff5c485c9 in raise () from /lib64/libc.so.6
#1 0x00007ffff5c49cd8 in abort () from /lib64/libc.so.6
#2 0x00007ffff6efbd47 in bson_append_date_time () from /usr/lib64/libbson-1.0.so.0
#3 0x00007ffff6f02fb3 in _bson_json_read_end_map () from /usr/lib64/libbson-1.0.so.0
#4 0x00007ffff6f0a80d in yajl_do_parse () from /usr/lib64/libbson-1.0.so.0
#5 0x00007ffff6f0345e in bson_json_reader_read () from /usr/lib64/libbson-1.0.so.0
#6 0x000000000044066f in MongoDBClient::Json2Bson (
json="{\"$date\" : { \"$numberLong\" : \"1455853006123\"}}") at MongoDBClient.cpp:99
#7 0x0000000000444d0b in MongoDBProxyQuestProcessor::singleFind (this=this@entry=0xf8c018, args=
std::shared_ptr (count 4, weak 0) 0xf4ce00, quest=std::shared_ptr (count 7, weak 0) 0xf4d580,
hintId=hintId@entry=0, onlyHashTable=onlyHashTable@entry=false)
at MongoDBProxyQuestProcessor.cpp:136

---------------------
case 2
---------------------
JSON string: {"$oid" : { "$numberLong" : "1455853006123"}}

screen output:
src/bson/bson.c:1144 bson_append_int64(): precondition failed: key

crashed service stack by gdb:
---------------------
#0 0x00007ffff5c485c9 in raise () from /lib64/libc.so.6
#1 0x00007ffff5c49cd8 in abort () from /lib64/libc.so.6
#2 0x00007ffff6efb457 in bson_append_int64 () from /usr/lib64/libbson-1.0.so.0
#3 0x00007ffff6f0320c in _bson_json_read_end_map () from /usr/lib64/libbson-1.0.so.0
#4 0x00007ffff6f0a80d in yajl_do_parse () from /usr/lib64/libbson-1.0.so.0
#5 0x00007ffff6f0345e in bson_json_reader_read () from /usr/lib64/libbson-1.0.so.0
#6 0x000000000044066f in MongoDBClient::Json2Bson (
json="{\"$oid\" : { \"$numberLong\" : \"1455853006123\"}}") at MongoDBClient.cpp:99
#7 0x0000000000444d0b in MongoDBProxyQuestProcessor::singleFind (this=this@entry=0xf8c018, args=
std::shared_ptr (count 4, weak 0) 0xf4d640, quest=std::shared_ptr (count 7, weak 0) 0xf4d680,
hintId=hintId@entry=0, onlyHashTable=onlyHashTable@entry=false)
at MongoDBProxyQuestProcessor.cpp:136

---------------------
case 3
---------------------
JSON string:

{"$oid" : "563b029096f9bc35c61df3a3"}

screen output:
src/bson/bson.c:1405 bson_append_oid(): precondition failed: key

crashed service stack by gdb:
---------------------
#0 0x00007ffff5c485c9 in raise () from /lib64/libc.so.6
#1 0x00007ffff5c49cd8 in abort () from /lib64/libc.so.6
#2 0x00007ffff6efb775 in bson_append_oid () from /usr/lib64/libbson-1.0.so.0
#3 0x00007ffff6f0305b in _bson_json_read_end_map () from /usr/lib64/libbson-1.0.so.0
#4 0x00007ffff6f0a80d in yajl_do_parse () from /usr/lib64/libbson-1.0.so.0
#5 0x00007ffff6f0345e in bson_json_reader_read () from /usr/lib64/libbson-1.0.so.0
#6 0x000000000044066f in MongoDBClient::Json2Bson (json="

{\"$oid\" : \"563b029096f9bc35c61df3a3\"}

")
at MongoDBClient.cpp:99
#7 0x0000000000444d0b in MongoDBProxyQuestProcessor::singleFind (this=this@entry=0xf8c018, args=
std::shared_ptr (count 4, weak 0) 0xf4d440, quest=std::shared_ptr (count 7, weak 0) 0xf4d480,
hintId=hintId@entry=0, onlyHashTable=onlyHashTable@entry=false)
at MongoDBProxyQuestProcessor.cpp:136

---------------------
My convert function:
(Service is development by C++11 with Mongo C Driver.)
---------------------

bson_t* MongoDBClient::Json2Bson(const std::string& json)
{
const size_t buffsize = 512;
bson_json_reader_t *reader = bson_json_data_reader_new(1, buffsize);
if (reader == NULL)
return NULL;

bson_json_data_reader_ingest(reader, (const uint8_t *)json.data(), json.length());

bson_error_t error;
bson_t* doc = bson_new();
bson_t* doc2 = bson_new();

int state = bson_json_reader_read (reader, doc, &error);
if (state < 0)

{ bson_destroy (doc); bson_destroy (doc2); bson_json_reader_destroy (reader); LOG_ERROR("convert json %s to bson failed. error: %s", json.c_str(), error.message); return NULL; }

state = bson_json_reader_read (reader, doc2, &error);
if (state != 0)

{ bson_destroy (doc); bson_destroy (doc2); bson_json_reader_destroy (reader); LOG_ERROR("convert json %s to bson failed. Json not a single object, reentered.", json.c_str()); return NULL; }

bson_destroy (doc2);
bson_json_reader_destroy (reader);

return doc;
}