gzip/squish.gzip.lua

function gzip_file(infile_fn, outfile_fn)

	local infile, err = io.open(infile_fn);

	if not infile then

		print_err("Can't open input file for reading: "..tostring(err));

		return;

	end

	local outfile, err = io.open(outfile_fn..".gzipped", "wb+");

	if not outfile then

		print_err("Can't open output file for writing: "..tostring(err));

		return;

	end

	local data = infile:read("*a");

	infile:close();

	local shebang, newdata = data:match("^(#.-\n)(.+)$");

	local code = newdata or data;

	if shebang then

		outfile:write(shebang)

	end

	local file_with_no_shebang, err = io.open(outfile_fn..".pregzip", "wb+");

	if not file_with_no_shebang then

		print_err("Can't open temp file for writing: "..tostring(err));

		return;

	end

	file_with_no_shebang:write(code);

	file_with_no_shebang:close();

	local compressed = io.popen("gzip -c '"..outfile_fn..".pregzip'");

	code = compressed:read("*a");

	compressed:close();

	os.remove(outfile_fn..".pregzip");

	local maxequals = 0;

	code:gsub("(=+)", function (equals_string) maxequals = math.max(maxequals, #equals_string); end);

	outfile:write("local ungz = (function ()", require_resource "gunzip.lua", " end)()\n");

	outfile:write[[return assert(loadstring((function (i)local o={} ungz{input=i,output=function(b)table.insert(o,string.char(b))end}return table.concat(o)end) ]];

	--outfile:write [[return assert(loadstring(_gunzip]]

	outfile:write((string.format("%q", code):gsub("\026", "\\026")));

	--outfile:write("[", string.rep("=", maxequals+1), "[", code, "]", string.rep("=", maxequals+1), "]");

	outfile:write(", '@", outfile_fn,"'))()");

	outfile:close();

	os.rename(outfile_fn..".gzipped", outfile_fn);

end

if opts.gzip then

	print_info("Gzipping "..out_fn.."...");

	gzip_file(out_fn, out_fn);

	print_info("OK!");

end