Add context pointer to httpc_options

[Marco Nilsson]

Would it be possible to add a void *context to the options struct? That would make it easier to use in C++ when you need to access class members. Example:

// Static method to enable calls from C.
int HttpClient::HttpOpen(void **socket, struct httpc_options *os, void *opts, const char *domain, unsigned short port, int use_ssl)
{
    HttpClient * self = reinterpret_cast<HttpClient *>(os->context);
    auto res = self->socketFactory.CreateSocket();
    ...
}

[James]

That sounds like a good idea and it can be added to in a backwards compatible way by adding the context pointer to the end of the httpc_options structure. I should probably write a C++ wrapper at some point but I'm very rusty (no pun) with it.

[Marco Nilsson]

It would also be good to have it accessible in the time and sleep functors, but that can't be made backwards compatible :(

[James]

I might add it and bump the major version number, I know how annoying it is to deal with callbacks that do not allow a user defined param field.