Building on Windows

[wotzlaff]

Here, I want to keep track of the current status of building the library on Windows.
The ultimate aim would be to provide a prebuilt version over npm.

What I did so far:

• Get rid of the uname part in package.json (used for npm install on macOS) since uname fails on Windows.
• Switch language to node_js in Travis and try to use Windows as OS.

Currently, I am facing problems with the CALLBACK macro which is defined in the win headers but conflicts with our enum value from ParameterType.

[wotzlaff]

Some more problems that could be solved are:

• fix includes in bindings.gyp
• use guint instead of uint (as the latter is not defined) - the definition in bindings.gyp seemed to conflict with ffi.h
• rename CALLBACK and interface as these are predefined macros

Now I find that g_source_add_unix_fd in loop.cc is not available on Windows. Is there any possibility to get rid of this?

[romgrk]

g_source_add_unix_fd: let's hope. I have no idea what a replacement for that would be on windows. That part of code is where we tell GLib to use libuv's fd to check for events. UV does seem to return something on Windows (link), a HANDLE. But I have zero idea how they epoll on Windows. This will be an interesting experience.

[romgrk]

First issue: on Windows, uv_backend_fd() doesn't even return a valid value. I've opened an issue on nodejs to check it it's possible to get it working in future versions. I think fom reading the past discussions it would be possible to retrieve what we want through loop->iocp, which is an internal private field but it "should not change".

Second issue: I'm not really sure what to do with this HANDLE iocp thing. We'll need to add some way for our GSource to get events from that thing. g_source_add_poll(source, fd) and the undocumented & private g_io_channel_win32_make_pollfd could work. I just need to find how to turn the thing into a GIOChannel. Otherwise if it's not possible to turn that thing into a pollable fd, I guess we'll need to make the polling ourselves using windows API.

[ten0s]

Do we have an example that does work on Linux and MacOS and doesn't on Windows due to the loop(s) problem?

[ten0s]

I'm asking because I didn't see a need for it yet in the context of Gtk 3.0. User initiated events work!

[romgrk]

I'm asking because I didn't see a need for it yet in the context of Gtk 3.0. User initiated events work!

It's been a while since I looked into it, and I've never built/used on windows so I wouldn't know :| But it's nice to hear.

The loop integration issues make things weird in edge cases; sometimes you can't cross an async-boundary because the uv loop has been essentially stopped; so simple user-clicks-callback-runs sequences are fine, but event loop callbacks aren't so fine (e.g. timers, promises, etc).

[ten0s]

This is why I ask for some example. It's hardly possible to move forward and decide what should/shouldn't be done without one.

[romgrk]

We can close this issue as the windows build is working. For the other problems, discussion can be continued in their own issue.