# HG changeset patch
# User Kim Alvefur <zash@zash.se>
# Date 1452642354 -3600
# Node ID 7be4ebefd1f4e0ccfb9a3b6c247b1135e095cb66
# Parent  82ad158714e54397f02c175252f648deaf37833b
util.random: Use /dev/urandom or LuaCrypto

diff -r 82ad158714e5 -r 7be4ebefd1f4 util/random.lua
--- a/util/random.lua	Tue Jan 12 13:14:36 2016 +0000
+++ b/util/random.lua	Wed Jan 13 00:45:54 2016 +0100
@@ -6,38 +6,14 @@
 -- COPYING file in the source package for more information.
 --
 
-local tostring = tostring;
-local os_time = os.time;
-local os_clock = os.clock;
-local ceil = math.ceil;
-local H = require "util.hashes".sha1;
+local urandom = io.open("/dev/urandom", "r");
 
-local last_uniq_time = 0;
-local function uniq_time()
-	local new_uniq_time = os_time();
-	if last_uniq_time >= new_uniq_time then new_uniq_time = last_uniq_time + 1; end
-	last_uniq_time = new_uniq_time;
-	return new_uniq_time;
-end
-
-local function new_random(x)
-	return H(x..os_clock()..tostring({}));
+if urandom then
+	return {
+		seed = function () end;
+		bytes = function (n) return urandom:read(n); end
+	};
 end
 
-local buffer = new_random(uniq_time());
-
-local function seed(x)
-	buffer = new_random(buffer..x);
-end
-
-local function bytes(n)
-	if #buffer < n+4 then seed(uniq_time()); end
-	local r = buffer:sub(1, n);
-	buffer = buffer:sub(n+1);
-	return r;
-end
-
-return {
-	seed = seed;
-	bytes = bytes;
-};
+local crypto = require "crypto"
+return crypto.rand;