It is best to pass as few parameters to EVP_*Init_ex() as possible. Passing a key, IV, or cipher will cause redundant work to happen behind the scenes as OpenSSL doesn't check whether they have actually changed. This avoids a malloc()/free() and redoing AES key expansion for every message that is encrypted and decrypted.
Moonlight Streaming Core Library
Moonlight-common-c contains the core GameStream client code shared between Moonlight clients, including Moonlight PC, Moonlight Android, Moonlight iOS, and Moonlight Chrome.
If you are implementing your own Moonlight game streaming client that can use a C library, you probably want the code here.
Note to Developers
Moonlight-common-c requires the specific version of ENet that is bundled as a submodule. This version has changes required for IPv6 compatibility and retransmission reliability, among other things. These are breaking API/ABI changes which make Moonlight-common-c incompatible with other versions of the ENet library. Attempting to runtime link to another libenet library will cause your client to crash when connecting to recent versions of GeForce Experience.