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authorMike Buland <eichlan@xagasoft.com>2012-05-22 17:15:40 +0000
committerMike Buland <eichlan@xagasoft.com>2012-05-22 17:15:40 +0000
commitce793e31f387c0715fa5b50c20e06510cc3e95ff (patch)
tree5b15972bdcbe7a26933e8158f52b29fb014dc421 /src/experimental/randomcmwc.cpp
parent2295579eb790d6eff6e54e84c01da6de10809a71 (diff)
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Moved random to stable, just needs some minor tweaks. But it's already in use
in a couple of core components, including in tempFile name generation.
Diffstat (limited to 'src/experimental/randomcmwc.cpp')
-rw-r--r--src/experimental/randomcmwc.cpp52
1 files changed, 0 insertions, 52 deletions
diff --git a/src/experimental/randomcmwc.cpp b/src/experimental/randomcmwc.cpp
deleted file mode 100644
index a4e807e..0000000
--- a/src/experimental/randomcmwc.cpp
+++ /dev/null
@@ -1,52 +0,0 @@
1/*
2 * Copyright (C) 2007-2012 Xagasoft, All rights reserved.
3 *
4 * This file is part of the libbu++ library and is released under the
5 * terms of the license contained in the file LICENSE.
6 */
7
8#include "bu/randomcmwc.h"
9
10#define PHI 0x9e3779b9
11
12Bu::RandomCmwc::RandomCmwc() :
13 q( 0 ),
14 c( 362436 )
15{
16 q = new uint32_t[4096];
17}
18
19Bu::RandomCmwc::~RandomCmwc()
20{
21 delete[] q;
22}
23
24void Bu::RandomCmwc::seed( int32_t iSeed )
25{
26 int i;
27
28 q[0] = iSeed;
29 q[1] = iSeed + PHI;
30 q[2] = iSeed + PHI + PHI;
31
32 for (i = 3; i < 4096; i++)
33 q[i] = q[i - 3] ^ q[i - 2] ^ PHI ^ i;
34}
35
36int32_t Bu::RandomCmwc::rand()
37{
38 uint64_t t, a = 18782LL;
39 static uint32_t i = 4095;
40 uint32_t x, r = 0xfffffffe;
41 i = (i + 1) & 4095;
42 t = a * q[i] + c;
43 c = (t >> 32);
44 x = t + c;
45 if( x < c )
46 {
47 x++;
48 c++;
49 }
50 return (q[i] = r - x);
51}
52