Add download progress handler for CEF in premake (PR #3988)

Author: TheNormalnij

utils/buildactions/install_cef.lua

@@ -111,7 +111,7 @@ newaction {
 		else
 			-- Download CEF
 			print("Downloading CEF " .. CEF_VERSION ..  "...")
-			if not http.download_print_errors(make_cef_download_url(), archive_path) then
+			if not http.download_print_errors(make_cef_download_url(), archive_path, { progress = http.create_download_progress_handler{update_interval_s = 5} }) then
 				os.exit(1)
 				return
 			end

utils/buildactions/utils.lua

@@ -129,6 +129,24 @@ function os.extract_archive(archive_path, target_path, override)
 	return false
 end
 
+function http.create_download_progress_handler(options)
+	local last_update = 0
+
+	return function (total, current)
+		local tick = os.clock()
+		if tick - last_update < options.update_interval_s then
+			return
+		end
+
+		last_update = tick
+
+		local ratio = current / total;
+		ratio = math.min(math.max(ratio, 0), 1)
+		local percent = math.floor(ratio * 100)
+		print(string.format("Downloading (%d/%d) %d%%", current, total, percent))
+	end
+end
+
 function http.download_print_errors(url, file, options)
 	local result_str, response_code = http.download(url, file, options)
 	if result_str ~= "OK" then