Added os detection

lib/getOS.lua

@@ -0,0 +1,73 @@
+function getOS()
+	local raw_os_name, raw_arch_name = '', ''
+
+	-- LuaJIT shortcut
+	if jit and jit.os and jit.arch then
+		raw_os_name = jit.os
+		raw_arch_name = jit.arch
+	else
+		-- is popen supported?
+		local popen_status, popen_result = pcall(io.popen, "")
+		if popen_status then
+			popen_result:close()
+			-- Unix-based OS
+			raw_os_name = io.popen('uname -s','r'):read('*l')
+			raw_arch_name = io.popen('uname -m','r'):read('*l')
+		else
+			-- Windows
+			local env_OS = os.getenv('OS')
+			local env_ARCH = os.getenv('PROCESSOR_ARCHITECTURE')
+			if env_OS and env_ARCH then
+				raw_os_name, raw_arch_name = env_OS, env_ARCH
+			end
+		end
+	end
+
+	raw_os_name = (raw_os_name):lower()
+	raw_arch_name = (raw_arch_name):lower()
+
+	local os_patterns = {
+		['windows'] = 'Windows',
+		['linux'] = 'Linux',
+		['mac'] = 'Mac',
+		['darwin'] = 'Mac',
+		['^mingw'] = 'Windows',
+		['^cygwin'] = 'Windows',
+		['bsd$'] = 'BSD',
+		['SunOS'] = 'Solaris',
+	}
+	
+	local arch_patterns = {
+		['^x86$'] = 'x86',
+		['i[%d]86'] = 'x86',
+		['amd64'] = 'x86_64',
+		['x86_64'] = 'x86_64',
+		['Power Macintosh'] = 'powerpc',
+		['^arm'] = 'arm',
+		['^mips'] = 'mips',
+	}
+
+	local os_name, arch_name = 'unknown', 'unknown'
+
+	for pattern, name in pairs(os_patterns) do
+		if raw_os_name:match(pattern) then
+			os_name = name
+			break
+		end
+	end
+	for pattern, name in pairs(arch_patterns) do
+		if raw_arch_name:match(pattern) then
+			arch_name = name
+			break
+		end
+	end
+	return os_name, arch_name
+end
+
+if select(1, ...) ~= 'os_name' then
+	print(("%q %q"):format(getOS()))
+else
+	return {
+		getOS = getOS,
+	}
+end