From bf734679a7643e4cf54e192cb8a624c92fc2da64 Mon Sep 17 00:00:00 2001 From: P. J. McDermott Date: Wed, 27 Aug 2014 22:03:05 -0400 Subject: lib/rand.sh: New file --- (limited to 'lib/rand.sh') diff --git a/lib/rand.sh b/lib/rand.sh new file mode 100644 index 0000000..19d6e9f --- /dev/null +++ b/lib/rand.sh @@ -0,0 +1,48 @@ +# Linear congruential pseudorandom number generator +# +# Copyright (C) 2014 Patrick "P. J." McDermott +# +# This file is part of the ProteanOS Development Kit. +# +# The ProteanOS Development Kit is free software: you can redistribute +# it and/or modify it under the terms of the GNU General Public License +# as published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. +# +# The ProteanOS Development Kit is distributed in the hope that it +# will be useful, but WITHOUT ANY WARRANTY; without even the implied +# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +# See the GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with the ProteanOS Development Kit. If not, see +# . + +[ "x${_RAND_SM+set}" = 'xset' ] && return 0 +_RAND_SM=1 + +use output +use locale + +rand_x=1 + +srand() +{ + local x="${1}" + + case "${x}" in + [!0-9]) + warn "$(get_msg 'rand_bad_x')" + return 1 + ;; + esac + + rand_x=${x} +} + +rand() +{ + # Increment, multiplier, and modulus values are those used in glibc. + rand_x=$((1103515245 * $rand_x + 12345)) + rand_x=$(($rand_x % 4294967296)) +} -- cgit v0.9.1