msgpack
bad_cast exception when msgpack::unpack
Hi All,
I am getting bad_cast while msgpack::unpack message. There are two process involved ,one is packing and another process unpacking. Tried to unpack immediately after pack in the same process and unpacking is successful. But when tried to unpack in another process failing with bad_cast.
Below are the deatils:
int32_t xyz::sendMsg() { std::stringstream ss; msgpack::pack(ss,*this);
GroupRpyMsg rpyMsg;
bool rtn = unpackMsg(rpyMsg, ss.str().data() , ss.str().size());
if(rtn)
{
std::cout << "send Success: " << rpyMsg.string().c_str() << std::endl;
}
else
{
std::cout << "send Failed: " << rpyMsg.string().c_str() << std::endl;
}
return send(ss.str().data(), ss.str().size());
}
template<typename T> bool unpackMsg(T& tobj, const char* buf, size_t size) { msgpack::unpacked unp; msgpack::unpack(unp, buf, size); msgpack::object obj = unp.get(); try {
tobj = obj.as<T>();
/*Printing*/
std::cout << "T: ";
std::cout << typeid(T).name() << std::endl;
std::cout << "buf: ";
for (std::size_t i = 0;
i != size;
++i) {
std::cout << std::hex << std::setw(2) << std::setfill('0');
std::cout << (static_cast<int>((buf + size)[i]) & 0xff) << ' ';
}
std::cout << std::endl;
std::cout << "obj: ";
std::cout << obj << std::endl;
std::cout << "Success: " << std::endl;
return true;
}
catch (const msgpack::type_error& err) {
/*Printing*/
std::cout << "T: ";
std::cout << typeid(T).name() << std::endl;
std::cout << "buf: ";
for (std::size_t i = 0;
i != size;
++i) {
std::cout << std::hex << std::setw(2) << std::setfill('0');
std::cout << (static_cast<int>((buf + size)[i]) & 0xff) << ' ';
}
std::cout << std::endl;
std::cout << "obj: ";
std::cout << obj << std::endl;
std::cout << error: " << err.what() << std::endl;
return false;
}
}
Trying to print values when success and in failure Time.
FAIL:
T: 14GroupRpyMsg
buf: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 b1 01 00 00 00 00 00 00 78 00 00 d4 28 7f 00 00 78 00 00 d4 28 7f 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 41 01 00 00 00 00 00 00 78 00 00 d4 28 7f 00 00 78 00 00 d4 28 7f 00 00 00 00 00 00 00 00 00 00 81 01 00 00 00 00 00 00 60 73 30 d4 28 7f 00 00 78 00
obj: {"msgId_":1, "src_":{"taskId":ad, "appId":0}, "dest_":{"taskId":ba, "appId":9}, "groupName_":"", "action_":0, "result_":0, "size_":0, "group_":{"name_":"", "nodes_":[]}, "nodeName_":"10.1.1.2", "nodeAddr_":"10.1.1.2", "clusterState_":1}
error: std::bad_cast
SUCCESS:
Below is another thread unpacking same response and unpack success: LES :
T: 14GroupRpyMsg
buf: 00 09 10 a6 7f 00 00 21 00 00 00 00 00 00 00 60 20 0a 10 a6 7f 00 00 40 bf 7f 10 a6 7f 00 00 20 00 00 00 00 00 00 00 64 00 00 00 00 00 00 00 48 00 00 00 00 00 00 00 af be ed fe 00 00 00 00 08 76 41 2e a6 7f 00 00 e0 75 41 2e a6 7f 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 aa 42 2e a6 7f 00 00 01 00 00 00 09 00 00 00 45 00 00 00 00 00 00 00 26 00 00 00 00 00 00 00 af be ed fe 00 00 00 00 2f 76 61 72 2f 6c 6f 67 2f 73 6f 6e 75 73 2f 74 6d 70
obj: {"msgId_":1, "src_":{"taskId":ad, "appId":0}, "dest_":{"taskId":ae, "appId":1}, "groupName_":"", "action_":0, "result_":0, "size_":0, "group_":{"name_":"", "nodes_":[]}, "nodeName_":"10.1.1.2", "nodeAddr_":"10.1.1.2", "clusterState_":1}
Success:
In Above both the SUCESS and FAILURE obj: printing is same,not understanding,why bad cast error is coming? Note: taskId":is different in both logs
Please let me know if you need any input?
Thanks Mayou
Could you update your code using https://guides.github.com/features/mastering-markdown/ ? It's very difficult to read.
Hi All,
I am getting bad_cast while msgpack::unpack message. There are two process involved ,one is packing and another process unpacking. Tried to unpack immediately after pack in the same process and unpacking is successful. But when tried to unpack in another process failing with bad_cast.
Below are the deatils:
int32_t xyz::sendMsg()
{
std::stringstream ss;
msgpack::pack(ss,*this);
**/unpacking in same function*/**
GroupRpyMsg rpyMsg;
bool rtn = unpackMsg(rpyMsg, ss.str().data() , ss.str().size());
if(rtn)
{
std::cout << "send Success: " << rpyMsg.string().c_str() << std::endl;
}
else
{
std::cout << "send Failed: " << rpyMsg.string().c_str() << std::endl;
}
return send(ss.str().data(), ss.str().size()); **/*Sending to another thread*/**
}
template
bool unpackMsg(T& tobj, const char* buf, size_t size)
{
msgpack::unpacked unp;
msgpack::unpack(unp, buf, size);
msgpack::object obj = unp.get();
try
{
tobj = obj.as<T>();
**/*Printing*/**
std::cout << "T: ";
std::cout << typeid(T).name() << std::endl;
std::cout << "buf: ";
for (std::size_t i = 0;
i != size;
++i) {
std::cout << std::hex << std::setw(2) << std::setfill('0');
std::cout << (static_cast<int>((buf + size)[i]) & 0xff) << ' ';
}
std::cout << std::endl;
std::cout << "obj: ";
std::cout << obj << std::endl;
std::cout << "Success: " << std::endl;
return true;
}
catch (const msgpack::type_error& err) {
/*Printing*/
std::cout << "T: ";
std::cout << typeid(T).name() << std::endl;
std::cout << "buf: ";
for (std::size_t i = 0;
i != size;
++i) {
std::cout << std::hex << std::setw(2) << std::setfill('0');
std::cout << (static_cast<int>((buf + size)[i]) & 0xff) << ' ';
}
std::cout << std::endl;
std::cout << "obj: ";
std::cout << obj << std::endl;
std::cout << error: " << err.what() << std::endl;
return false;
}
}
Trying to print values when success and in failure Time.
FAIL CASE
T: 14GroupRpyMsg buf: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 b1 01 00 00 00 00 00 00 78 00 00 d4 28 7f 00 00 78 00 00 d4 28 7f 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 41 01 00 00 00 00 00 00 78 00 00 d4 28 7f 00 00 78 00 00 d4 28 7f 00 00 00 00 00 00 00 00 00 00 81 01 00 00 00 00 00 00 60 73 30 d4 28 7f 00 00 78 00 obj: {"msgId_":1, "src_":{"taskId":ad, "appId":0}, "dest_":{"taskId":ba, "appId":9}, "groupName_":"", "action_":0, "result_":0, "size_":0, "group_":{"name_":"", "nodes_":[]}, "nodeName_":"10.1.1.2", "nodeAddr_":"10.1.1.2", "clusterState_":1} error: std::bad_cast
SUCCESS CASE
Below is another thread unpacking same response and unpack success:
T: 14GroupRpyMsg buf: 00 09 10 a6 7f 00 00 21 00 00 00 00 00 00 00 60 20 0a 10 a6 7f 00 00 40 bf 7f 10 a6 7f 00 00 20 00 00 00 00 00 00 00 64 00 00 00 00 00 00 00 48 00 00 00 00 00 00 00 af be ed fe 00 00 00 00 08 76 41 2e a6 7f 00 00 e0 75 41 2e a6 7f 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 aa 42 2e a6 7f 00 00 01 00 00 00 09 00 00 00 45 00 00 00 00 00 00 00 26 00 00 00 00 00 00 00 af be ed fe 00 00 00 00 2f 76 61 72 2f 6c 6f 67 2f 73 6f 6e 75 73 2f 74 6d 70 obj: {"msgId_":1, "src_":{"taskId":ad, "appId":0}, "dest_":{"taskId":ae, "appId":1}, "groupName_":"", "action_":0, "result_":0, "size_":0, "group_":{"name_":"", "nodes_":[]}, "nodeName_":"10.1.1.2", "nodeAddr_":"10.1.1.2", "clusterState_":1}
Success:
In Above both the **SUCESS and FAILURE obj: printing is same ** ,not understanding,why bad cast error is coming?
Note: taskId":is different in both logs
Please let me know if you need any input?
Thanks Mayou
MessagePack format is defined as follows: https://github.com/msgpack/msgpack/blob/master/spec.md
It seems that your buf: is not correct. obj: indicates that the data is MAP format family. https://github.com/msgpack/msgpack/blob/master/spec.md#map-format-family
However, buf: starts with 00.
Here is a simple program to check from hexfile to msgpack::object and convert your type.
https://wandbox.org/permlink/3ePESIFSXXCMJjwe
- Edit
msgpack.dat, 2nd tab. - Edit
type, line 24. - Run