Hello,
I have a question regarding SSL_write() and returning SSL_ERROR_WANT_WRITE from the write callback.
_After_ SSL_write() returns with SSL_ERROR_WANT_WRITE (because my write callback returned
SSL_ERROR_WANT_WRITE), can I _then_ send the data given to the calback and then call SSL_write() again (with the same arguments) and then in the second call to the callback return the number of bytes written? Is that a supported use of the API? (I'm asking because that's the only way I can use the API, I can't send the data inside the callback, I need to send it outside the callback, see below for why).
In other words, is it guaranteed that on that second call to
SSL_write(), SSL will want to send the exact same data that it tried before when it failed, and not change its mind about it wants to send? Because technically, since SSL_ERROR_WANT_WRITE implies that "no data was sent", the state machine might as well advance and send something different at a later time (because it received data or something inside expired or whatever).
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Why I need this: I'm using IOCP and LuaJIT which means I have two limitations:
1) Because I'm using a completion API as opposed to a readiness API, I can't just tell OpenSSL when the socket is writable and let it write to it, I need to write the data myself.
2) because LuaJIT doesn't allow me to yield from inside a C callback, I can't do async I/O inside the callback, I can only do it in between calls to SSL_read()/SSL_write().
Any suggestions appreciated, thanks!
