[Web] Disable UNIX sockets

[Faless]

They are not supported anyway, emscripten has an emulation layer that implements them over WebSocket/WebRTC, which is really surprising for users, and also not very useful since we have proper WebSocket and WebRTC support.

This can make the build smaller, if we also disable the UPNP module (which will otherwise include a third party library referencing "socket" thus forcing emscripten to include the compatibility layer)

Fixes #98389

[akien-mga]

Should we call this POSIX_SOCKET_UNAVAILABLE? Technically it's about the Unix implementation, but the class it disables is the Posix one and includes the Windows implementation too.

[Faless]

Maybe POSIX_SOCKET_UNAVAILABLE would indeed be a better name.

I'm just reusing UNIX_SOCKET_UNAVAILABLE which was added in #32454 to allow building on some console platform.

I've actually been thinking about splitting Windows sockets since they've diverged quite a bit from the posix one (and their "compatibility" layer is not compatible)

[akien-mga]

Yeah splitting Windows sockets might make sense, I've thought about this too on and off.

[Faless]

I've opened #98969 which does that.

[akien-mga]

This should probably be documented in some places?

[dustdfg]

This can make the build smaller, if we also disable the UPNP module (which will otherwise include a third party library referencing "socket" thus forcing emscripten to include the compatibility layer)

What is the problem with disabling it? Something in web heavily depends on it? I don't know anything about network but from reading description on site of miniupnp I got a feeling it anyway won't work in web or not?

It looks like it can be easily disabled like already disabled raycast module

godot/platform/web/detect.py

Lines 68 to 75 in cf35f25

	def get_flags():
	return {
	"arch": "wasm32",
	"target": "template_debug",
	"builtin_pcre2_with_jit": False,
	"vulkan": False,
	# Embree is heavy and requires too much memory (GH-70621).
	"module_raycast_enabled": False,

[Faless]

@dustdfg unlike the raycast module, UPNP adds exposed types. This means that if your GDScript includes references to that type, the script will fail parsing, even if you don't actually use it in web builds.

[Repiteo]

Needs to be rebased now that #98969 is merged

[Faless]

@Repiteo I rebased this on top of #99167 (fixup on #98969)

[Repiteo]

Thanks!