diff options
author | Timothy Pearson <tpearson@raptorengineering.com> | 2019-05-11 15:12:49 -0500 |
---|---|---|
committer | Timothy Pearson <tpearson@raptorengineering.com> | 2019-05-11 15:12:49 -0500 |
commit | 9e80202352dd49bdd9e67b8b906d86f058431505 (patch) | |
tree | 5673c17aad6e3833da8c4ff21b5a11f666ec9fbe /src/roms/u-boot/lib/rand.c | |
download | hqemu-master.zip hqemu-master.tar.gz |
Diffstat (limited to 'src/roms/u-boot/lib/rand.c')
-rw-r--r-- | src/roms/u-boot/lib/rand.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/src/roms/u-boot/lib/rand.c b/src/roms/u-boot/lib/rand.c new file mode 100644 index 0000000..5c367e1 --- /dev/null +++ b/src/roms/u-boot/lib/rand.c @@ -0,0 +1,32 @@ +/* + * Simple xorshift PRNG + * see http://www.jstatsoft.org/v08/i14/paper + * + * Copyright (c) 2012 Michael Walle + * Michael Walle <michael@walle.cc> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> + +static unsigned int y = 1U; + +unsigned int rand_r(unsigned int *seedp) +{ + *seedp ^= (*seedp << 13); + *seedp ^= (*seedp >> 17); + *seedp ^= (*seedp << 5); + + return *seedp; +} + +unsigned int rand(void) +{ + return rand_r(&y); +} + +void srand(unsigned int seed) +{ + y = seed; +} |