diff options
| author | Denys Vlasenko <vda.linux@googlemail.com> | 2009-10-09 20:59:04 +0200 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2009-10-09 20:59:04 +0200 |
| commit | 3ea2e82dc7b32703f5043c3b30b049905a0d07aa (patch) | |
| tree | eae992a986a4ce66efa32845ecccc204a0c4c0e1 /shell/random.h | |
| parent | a05b2b856bf095dfd5f575c106d1a9e5ac6edd3c (diff) | |
| download | busybox-3ea2e82dc7b32703f5043c3b30b049905a0d07aa.tar.gz | |
ash: factor out $RANDOM support
function old new delta
next_random - 46 +46
ash_main 1361 1356 -5
change_random 132 97 -35
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/2 up/down: 46/-40) Total: 6 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'shell/random.h')
| -rw-r--r-- | shell/random.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/shell/random.h b/shell/random.h new file mode 100644 index 000000000..2d29a60e8 --- /dev/null +++ b/shell/random.h @@ -0,0 +1,19 @@ +/* vi: set sw=4 ts=4: */ +/* + * $RANDOM support. + * + * Copyright (C) 2008 Denys Vlasenko + * + * Licensed under GPLv2, see file LICENSE in this tarball for details. + */ + +typedef struct random_t { + /* Random number generators */ + int32_t galois_LFSR; /* Galois LFSR (fast but weak). signed! */ + uint32_t LCG; /* LCG (fast but weak) */ +} random_t; + +#define INIT_RANDOM_T(rnd, nonzero, v) \ + ((rnd)->galois_LFSR = (nonzero), (rnd)->LCG = (v)) + +uint32_t next_random(random_t *rnd) FAST_FUNC; |