felspar-io Implementation

There are three implementations that support the Warden API:

• POSIX using poll
• Windows using WSAPoll
• Linux's io_uring

The poll and WSAPoll are similar, but not identical. The main part of the implementation is in:

• poll.hpp — Common header containing completion tracking and common retry and cancellation code.
• poll.iops.cpp — Implementation of the individual IOP APIs.
• poll.warden.cpp — Implementation of the poll loop itself together with other code needed to have everything work.

The differences between poll and WSAPoll are handled through #if blocks.

There is a separate implementation io_uring in the following files:

• uring.hpp — IOP delivery and completion header file.
• uring.iops.cpp — Implementation of the various IOPs.
• uring.warden.cpp — The io_uring submission and completion loop.

• convenience.cpp — Contains a few helpers.
• posix.cpp — Contains wrappers for some common POSIX APIs.
• tls.cpp — Contains an implementation of TLS using OpenSSL.
• warden.cpp — Common warden code (creating sockets and pipes).