From e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb Mon Sep 17 00:00:00 2001 From: Yang Zhang Date: Fri, 28 Aug 2015 09:58:54 +0800 Subject: Add qemu 2.4.0 Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang --- qemu/roms/ipxe/src/core/random.c | 41 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 qemu/roms/ipxe/src/core/random.c (limited to 'qemu/roms/ipxe/src/core/random.c') diff --git a/qemu/roms/ipxe/src/core/random.c b/qemu/roms/ipxe/src/core/random.c new file mode 100644 index 000000000..8824dca3a --- /dev/null +++ b/qemu/roms/ipxe/src/core/random.c @@ -0,0 +1,41 @@ +/** @file + * + * Random number generation + * + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +#include +#include + +static int32_t rnd_seed = 0; + +/** + * Seed the pseudo-random number generator + * + * @v seed Seed value + */ +void srandom ( unsigned int seed ) { + rnd_seed = seed; +} + +/** + * Generate a pseudo-random number between 0 and 2147483647L or 2147483562? + * + * @ret rand Pseudo-random number + */ +long int random ( void ) { + int32_t q; + + if ( ! rnd_seed ) /* Initialize linear congruential generator */ + srandom ( currticks() ); + + /* simplified version of the LCG given in Bruce Schneier's + "Applied Cryptography" */ + q = ( rnd_seed / 53668 ); + rnd_seed = ( 40014 * ( rnd_seed - 53668 * q ) - 12211 * q ); + if ( rnd_seed < 0 ) + rnd_seed += 2147483563L; + return rnd_seed; +} -- cgit 1.2.3-korg