Add command to launch CCEmuX

etc/ccemux.lua

@@ -0,0 +1,38 @@
+#!/usr/bin/env lua
+
+local function find_latest(dir)
+  local launcher = io.open(dir .. "/launcher.properties", "r")
+  if not launcher then return nil, "Cannot find CCEmuX" end
+
+  local info = {}
+  for line in launcher:lines() do
+    local k, v = line:match("^([^=]+)=(.*)$")
+    if k then info[k] = v end
+  end
+  launcher:close()
+
+  if not info.version or not info.build then return nil, "Cannot find CCEmuX version" end
+  return ("%s/versions/%s/CCEmuX-%s.jar"):format(dir, info.version, info.build)
+end
+
+local function guess_path()
+  local appdata = os.getenv("APPDATA")
+  if appdata then return find_latest(appdata:gsub("\\", "/") .. "/ccemux") end
+
+  local home = os.getenv("HOME") -- Probably should check XDG here too, but this works.
+  if home then return find_latest(home .. "/.local/share/ccemux") end
+
+  -- Who knows what OSX does‽ I don't.
+  return nil, "Cannot find CCEmuX installation directory"
+end
+
+local ccemux_path, err = ...
+if not ccemux_path then ccemux_path, err = guess_path() end
+if not ccemux_path then
+  io.stderr:write(err .. "\n")
+  os.exit(1)
+end
+
+local cmd = ("java -jar %q -c ."):format(ccemux_path)
+print("> " .. cmd)
+os.execute(cmd)