Add a safeguard to map command

[GeckoEidechse]

Adds safeguard to the map command that prevents it from executing if the requested map is invalid or no map argument is given.

This is basically #529 again which got reverted in #561 due to pg9182/northstar-dedicated#70

The issue in pg9182/northstar-dedicated#70 is likely caused by Wine and not launcher code. Nevertheless the PR got reverted due to not being able to locate the issue in Wine in a timely manner.

As such this PR here is marked as draft until we can figure out and solve the issue in Wine in the Docker image.

[GeckoEidechse]

cc @catornot

[Jan200101]

Figured it out (shoutouts to x64dbg) @GeckoEidechse

Stack Trace and Registers

Its crashing right here

NorthstarLauncher/NorthstarDLL/util/printmaps.cpp

Lines 106 to 116 in 0246053

	// get maps in game dir
	for (fs::directory_entry file : fs::directory_iterator(fmt::format("{}/maps", R2::g_pModName)))
	{
	if (file.path().extension() == ".bsp")
	{
	MapVPKInfo& map = vMapList.emplace_back();
	map.name = file.path().stem().string();
	map.parent = "R2";
	map.source = MapSource_t::GAMEDIR;
	}
	}

because in the Docker container there is no r2/maps it throws an exception which goes uncaught.
This was not caught on Windows because it was done on a full install with the maps folder intact.

Fixes are:

• putting it in a try ... catch (fs::filesystem_error)
• checking if the folder exists before iterating
• use the std::error_code overload of directory_iterator

[GeckoEidechse]

That's amazing, many thanks for taking your time to look into this <3

cc @catornot

[GeckoEidechse]

With #575 merged and this PR updated accordingly, this should work now.

[GeckoEidechse]

Test with

ghcr.io/pg9182/northstar-dedicated-ci:1-tf2.0.11.0-ns1.19.8-ci.c14bdc62.112.6533697962-nslauncher.0d07f4b2.6526237893

created via https://github.com/pg9182/northstar-dedicated-ci/actions/runs/6533697962

[catornot]

still works locally

👍