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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 16:00:33 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 16:00:33 +0000
commit96fcf3ea3a51071dfeca141b7c9b0e5e3e5365a8 (patch)
tree51d766882e3eacda67f6a3b0df8ae3df7d157e20 /src/isaac_rand/isaac64.c
parentInitial commit. (diff)
downloadnwipe-96fcf3ea3a51071dfeca141b7c9b0e5e3e5365a8.tar.xz
nwipe-96fcf3ea3a51071dfeca141b7c9b0e5e3e5365a8.zip
Adding upstream version 0.34.upstream/0.34upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/isaac_rand/isaac64.c')
-rw-r--r--src/isaac_rand/isaac64.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/src/isaac_rand/isaac64.c b/src/isaac_rand/isaac64.c
new file mode 100644
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--- /dev/null
+++ b/src/isaac_rand/isaac64.c
@@ -0,0 +1,119 @@
+/*
+------------------------------------------------------------------------------
+isaac64.c: My random number generator for 64-bit machines.
+By Bob Jenkins, 1996. Public Domain.
+------------------------------------------------------------------------------
+*/
+#ifndef STANDARD
+#include "isaac_standard.h"
+#endif
+#ifndef ISAAC64
+#include "isaac64.h"
+#endif
+
+
+#define ind(mm,x) (*(ub8 *)((ub1 *)(mm) + ((x) & ((RANDSIZ-1)<<3))))
+#define rngstep(mix,a,b,mm,m,m2,r,x) \
+{ \
+ x = *m; \
+ a = (mix) + *(m2++); \
+ *(m++) = y = ind(mm,x) + a + b; \
+ *(r++) = b = ind(mm,y>>RANDSIZL) + x; \
+}
+
+void isaac64(rand64ctx *ctx)
+{
+ register ub8 a,b,x,y,*m,*mm,*m2,*r,*mend;
+ mm=ctx->mm; r=ctx->randrsl;
+ a = ctx->aa; b = ctx->bb + (++ctx->cc);
+ for (m = mm, mend = m2 = m+(RANDSIZ/2); m<mend; )
+ {
+ rngstep(~(a^(a<<21)), a, b, mm, m, m2, r, x);
+ rngstep( a^(a>>5) , a, b, mm, m, m2, r, x);
+ rngstep( a^(a<<12) , a, b, mm, m, m2, r, x);
+ rngstep( a^(a>>33) , a, b, mm, m, m2, r, x);
+ }
+ for (m2 = mm; m2<mend; )
+ {
+ rngstep(~(a^(a<<21)), a, b, mm, m, m2, r, x);
+ rngstep( a^(a>>5) , a, b, mm, m, m2, r, x);
+ rngstep( a^(a<<12) , a, b, mm, m, m2, r, x);
+ rngstep( a^(a>>33) , a, b, mm, m, m2, r, x);
+ }
+ ctx->bb = b; ctx->aa = a;
+}
+
+#define mix(a,b,c,d,e,f,g,h) \
+{ \
+ a-=e; f^=h>>9; h+=a; \
+ b-=f; g^=a<<9; a+=b; \
+ c-=g; h^=b>>23; b+=c; \
+ d-=h; a^=c<<15; c+=d; \
+ e-=a; b^=d>>14; d+=e; \
+ f-=b; c^=e<<20; e+=f; \
+ g-=c; d^=f>>17; f+=g; \
+ h-=d; e^=g<<14; g+=h; \
+}
+
+void rand64init(rand64ctx *ctx, word flag)
+{
+ word i;
+ ub8 a,b,c,d,e,f,g,h;
+ ub8 *mm, *randrsl;
+ ctx->aa = ctx->bb = ctx->cc = (ub8)0;
+ mm=ctx->mm;
+ randrsl=ctx->randrsl;
+ a=b=c=d=e=f=g=h=0x9e3779b97f4a7c13LL; /* the golden ratio */
+
+ for (i=0; i<4; ++i) /* scramble it */
+ {
+ mix(a,b,c,d,e,f,g,h);
+ }
+
+ for (i=0; i<RANDSIZ; i+=8) /* fill in mm[] with messy stuff */
+ {
+ if (flag) /* use all the information in the seed */
+ {
+ a+=randrsl[i ]; b+=randrsl[i+1]; c+=randrsl[i+2]; d+=randrsl[i+3];
+ e+=randrsl[i+4]; f+=randrsl[i+5]; g+=randrsl[i+6]; h+=randrsl[i+7];
+ }
+ mix(a,b,c,d,e,f,g,h);
+ mm[i ]=a; mm[i+1]=b; mm[i+2]=c; mm[i+3]=d;
+ mm[i+4]=e; mm[i+5]=f; mm[i+6]=g; mm[i+7]=h;
+ }
+
+ if (flag)
+ { /* do a second pass to make all of the seed affect all of mm */
+ for (i=0; i<RANDSIZ; i+=8)
+ {
+ a+=mm[i ]; b+=mm[i+1]; c+=mm[i+2]; d+=mm[i+3];
+ e+=mm[i+4]; f+=mm[i+5]; g+=mm[i+6]; h+=mm[i+7];
+ mix(a,b,c,d,e,f,g,h);
+ mm[i ]=a; mm[i+1]=b; mm[i+2]=c; mm[i+3]=d;
+ mm[i+4]=e; mm[i+5]=f; mm[i+6]=g; mm[i+7]=h;
+ }
+ }
+
+ isaac64(ctx); /* fill in the first set of results */
+ ctx->randcnt=RANDSIZ; /* prepare to use the first set of results */
+}
+
+#ifdef NEVER
+int main()
+{
+ ub8 i,j;
+ rand64ctx ctx;
+ ctx.aa=ctx.bb=ctx.cc=(ub8)0;
+ for (i=0; i<RANDSIZ; ++i) ctx.mm[i]=(ub8)0;
+ rand64init(&ctx, TRUE);
+ for (i=0; i<2; ++i)
+ {
+ isaac64(&ctx);
+ for (j=0; j<RANDSIZ; ++j)
+ {
+ printf("%.8lx%.8lx",(ub4)(ctx.randrsl[j]>>32),(ub4)ctx.randrsl[j]);
+ if ((j&3)==3) printf("\n");
+ }
+ }
+}
+#endif