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author | David Lamparter <equinox@diac24.net> | 2010-02-04 03:41:06 +0100 |
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committer | David Lamparter <equinox@diac24.net> | 2010-02-04 03:41:06 +0100 |
commit | 447a9a8dbde95fc6ce92691491ac193f0199e2cd (patch) | |
tree | 4bfce47ead136e60cc91df50c3e79e75ddd4c83d /pimd/pim_rand.c | |
parent | 08e2c2ee9044a14f2cd9d382eec8f96189520160 (diff) | |
parent | 168595ff42c4046167b0fbae2770c037c854abd0 (diff) | |
download | quagga-447a9a8dbde95fc6ce92691491ac193f0199e2cd.tar.bz2 quagga-447a9a8dbde95fc6ce92691491ac193f0199e2cd.tar.xz |
Merge branch 'merged/pimd' into dn42
Conflicts:
lib/route_types.txt
Diffstat (limited to 'pimd/pim_rand.c')
-rw-r--r-- | pimd/pim_rand.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/pimd/pim_rand.c b/pimd/pim_rand.c new file mode 100644 index 00000000..df2a1111 --- /dev/null +++ b/pimd/pim_rand.c @@ -0,0 +1,60 @@ +/* + PIM for Quagga + Copyright (C) 2008 Everton da Silva Marques + + This program 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 2 of the License, or + (at your option) any later version. + + This program 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 this program; see the file COPYING; if not, write to the + Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, + MA 02110-1301 USA + + $QuaggaId: $Format:%an, %ai, %h$ $ +*/ + +#include "pim_rand.h" +#include "pim_time.h" + +/* Quick and dirty random number generator from NUMERICAL RECIPES IN C: + THE ART OF SCIENTIFIC COMPUTING (ISBN 0-521-43108-5). */ +/* BEWARE: '_qseed_' is assigned! */ +#define QRANDOM(_qseed_) ((_qseed_) = (((_qseed_) * 1664525L) + 1013904223L)) + +static long qpim_rand_seed; + +void pim_rand_init() +{ + qpim_rand_seed = pim_time_monotonic_sec() ^ getpid(); +} + +long pim_rand() +{ + return QRANDOM(qpim_rand_seed); +} + +int pim_rand_next(int min, int max) +{ + long rand; + + assert(min <= max); + + /* FIXME better random generator ? */ + + rand = QRANDOM(qpim_rand_seed); + if (rand < 0) + rand = -rand; + rand = rand % (1 + max - min) + min; + + assert(rand >= min); + assert(rand <= max); + + return rand; +} |