Question

Not much of a C++ developer and the multiple ways to handle strings always confuses me.

int Mine_SSL_Read(SSL* ssl, void* buf, int size)
{
    int length = Real_SSL_Read(ssl, buf, size);

    CString msg = ???
}

However I need to write a hook for SSL_Read function (OpenSSL) and that requires some C++ code. I need to convert buf which is of type void* and has a length of “length” into a CString so it can be parsed by other code.

Answer 1

Assuming the void* is simply one-byte (ASCII or similar) characters:

If you know it is NULL terminated, you can simply cast it:

// ASCII
CString msg = reinterpret_cast<char*>(buf);

// UNICODE
CString msg = reinterpret_cast<wchar_t*>(buf);

If it is not NULL terminated, or you don’t know that fact, then you have to copy it byte by byte (I don’t believe CString has an assign function similar to std::string).

CString msg;

char* str_buf = msg.GetBuffer();
char* msg_buf = reinterpret_cast<char*>(buf);

for(int x = 0; x < size; ++x)
    *str_buf++ = *msg_buf++;