module:set_global();

local traceback = require "util.debug".traceback;

local pposix = require "util.pposix";

local os_date = os.date;

local render_filename = require "util.interpolation".new("%b{}", function (s) return s; end, {

	yyyymmdd = function (t)

		return os_date("%Y%m%d", t);

	end;

	hhmmss = function (t)

		return os_date("%H%M%S", t);

	end;

});

local count = 0;

local function get_filename(filename_template)

	filename_template = filename_template;

	return render_filename(filename_template, {

		paths = prosody.paths;

		pid = pposix.getpid();

		count = count;

		time = os.time();

	});

end

local default_filename_template = "{paths.data}/traceback-{pid}-{count}.log";

local filename_template = module:get_option_string("debug_traceback_filename", default_filename_template);

local signal_name = module:get_option_string("debug_traceback_signal", "SIGUSR1");

function dump_traceback()

	module:log("info", "Received %s, writing traceback", signal_name);

	local tb = traceback();

	module:fire_event("debug_traceback/triggered", { traceback = tb });

	local f, err = io.open(get_filename(filename_template), "a+");

	if not f then

		module:log("error", "Unable to write traceback: %s", err);

		return;

	end

	f:write("-- Traceback generated at ", os.date("%b %d %H:%M:%S"), " --\n");

	f:write(tb, "\n");

	f:write("-- End of traceback --\n");

	f:close();

	count = count + 1;

end

local mod_posix = module:depends("posix");

if rawget(mod_posix, "features") and mod_posix.features.signal_events then

	module:hook("signal/"..signal_name, dump_traceback);

else

	require"util.signal".signal(signal_name, dump_traceback);

end