Application crashes while appending data on string - c++

Question

I have a cross platform console application. The purpose of it is to transfer data between two peers. Sometimes packets received are not complete so we append the data into a string while the complete packet has been arrived. But it get crashed in appending data in string after sometime. Here is the back tarce -
1 libsystem_c.dylib 0x93b77acf pthread_kill + 101
2 libsystem_c.dylib 0x93bae4f8 abort + 168
3 libc++abi.dylib 0x9698180c abort_message + 151
4 libc++abi.dylib 0x9697f275 default_terminate() + 34
5 libc++abi.dylib 0x9697f2b5 safe_handler_caller(void (*)()) + 13
6 libc++abi.dylib 0x9697f31d std::terminate() + 23
7 libc++abi.dylib 0x96980412 __cxa_throw + 110
8 libstdc++.6.dylib 0x90e23d6c std::__throw_length_error(char const*) + 104
9 libstdc++.6.dylib 0x90e4f3a9 std::string::append(char const*, unsigned long) + 175
10 libConnector.dylib 0x13905228 ConnectionSocket::AdjustPartialData(char const*, int)
14 libConnector.dylib 0x1383e0b6 ConnectionChannel::ProcessData(int, void const*, int, char*, int) + 7886
15 libConnector.dylib 0x13861ecb ConnectionManager::BaseThreadImpl() + 1185
16 libConnector.dylib 0x13861a23 ConnectionManager::BaseThread(void*) + 17
17 libsystem_c.dylib 0x93b76557 _pthread_start + 344
18 libsystem_c.dylib 0x93b60cee thread_start + 34
Can someone give any idea about this issue?
EXAMPLE CODE:
AdjustPartialData(char* const pData, int dataLen)
{
if (true == packetIncomplete)
{
partialDataBuffer.append(pData, dataLen); // crash occurs in this line
}
}

Answer 1

if partialDataBuffer.size() + dataLen > partialDataBuffer.max_size() then append throws a length_error (http://en.cppreference.com/w/cpp/string/basic_string/append)
Either partialDataBuffer or dataLen are too big.

Answer 2

Finally I have resolved the issue by discarding the extra data which causes the overflow. Previously I thought this will not be feasible solution as it could lead to possible data loss. But I found that TCP stream size shouldn't be greater than 65535 which is 16 bit. But found another issue when the following condition added -
if(partialDataBuffer.size() + dataLen >= partialDataBuffer.max_size())
{
// do not append data
}
else partialDataBuffer.append(pData, dataLen);
The issue was in windows platform it always crashes even though size of partialDataBuffer is much less than partialDataBuffer.max_size(). So, for resolving this issue I have done the following -
try{
partialDataBuffer.append(pData, dataLen);
}
catch(...)
{
// got exception, return
}
And it worked fine for me.
N.B: I have posted my answer because it will be helpful for others who are facing similar issue.