This is a small library that implements epoll on top of kqueue. It has been successfully used to port libinput, libevdev, Wayland and more software to FreeBSD: https://www.freshports.org/devel/libepoll-shim/
It may be useful for porting other software that uses epoll as well.
There are some tests inside test/. They should also compile under Linux and
can be used to verify proper epoll behavior.
However, this library contains some very ugly hacks and workarounds. For example:
- When using timerfd, signalfd or eventfd,
read,writeandcloseare redefined as macros to internal helper functions. This is needed as there is some internal context that has to be free'd properly. This means that you shouldn't create a timerfd/signalfd in one part of a program and close it in a different part wheresys/timerfd.hisn't included. The context would leak. Luckily, software such aslibinputbehaves very nicely and puts all timerfd related code in a single source file. - There is exactly one static int reserved for fds that can be polled but are
not supported by kqueue under FreeBSD. This includes graphics or sound
devices under
/dev. You can only have one of them throughout all epoll instances in your process!
Run the following commands to build libepoll-shim:
$ mkdir build
$ cd build
$ cmake .. -DCMAKE_BUILD_TYPE=RelWithDebInfo
$ cmake --build .
To run the tests:
$ ctest --output-on-failure
To install (as root):
# cmake --build . --target install