Question

What would you recommend I do to buffer multiple streams (each stream would require it’s own buffer) in C?

I sort of put together a solution in my head:

This is theoretical “pseudo code”

[ptr, ptr, ptr, ptr ... ]

Each ptr is a pointer to a struct:

{
    stream_id
    buff_ptr
}

stream_id is the ID of the stream (I have that information) and the buff_ptr is a pointer to some malloced data. Also, the buffers would probably have to be flexible and it’d have to call malloc and free a lot to make it flexible (at least I think it would?

I would basically find the buffer I need by iterating through the array of ptrs.

---

So, is that “architecture” good, or is there a better one?

If anyone is wondering “Why the nyan does she need that?!” I’ve made a server in Ruby/EventMachine, the protocol is really rotten (to say the least) and I don’t know how else to handle it… Unless there’s a way to force EventMachine to buffer it for me, that would be the best solution, I suppose.

Thanks.

P.S: Sorry for the rave! ~

Answer 1

Well, it seems the only option but you can change a few things:

• Don’t malloc and free. Use realloc instead

• Iterating through the list could be OK but if there are a lot of buffers

  • Can you make the caller pass you a pointer to the buffer ?
  • Can you use a hash instead of a list and search by stream_id ? For example glib2 provides such a hash

Many APIs (for example epoll) allow you to associate a pointer with an id (a descriptor in the case of epoll). When something interesting happens to that id, the API passes you your pointer -> zero search at the expense of 4-8 bytes of memory.