group test runs in randomcheck

ChangeLog

@@ -25,6 +25,9 @@ Version NEXT
 	SConstruct: declare CPP constant SIZEOF_LONG
 	randomcheck: use SIZEOF_LONG for grabing highest bits from long()
 	randomcheck: print more fraction digits in report
+	randomcheck: ability to run group tests with different seeds
+	  this will more balance results to be less initial seed
+	  dependant. classic fsp algo seems to produce best results.
 
 Version 2.8.1b29 - 24 Aug 2019
 	added scons command line argument without-fspscan=yes for building

tests/randomcheck.c

@@ -4,8 +4,10 @@
 #include "my-string.h"
 #include <math.h>
 
+static int group[4];
 static int bitcount[16];
 static int rounds;
+static int groups;
 static int result;
 #define MAX_WORST_ALLOWED 0.1f
 
@@ -76,17 +78,16 @@ static void run_randomtest( unsigned short (*keygen)(void) )
     }
 }
 
-static float print_bitcount(void)
+static void print_bitcount(void)
 {
     int i;
-    float worst;
+    float worst = 0;
-    float ratio;
 
     printf("Set ratio: ");
-    worst=0;
 
     for(i=0;i<16;i++)
     {
+        float ratio;
 	float delta;
         ratio=(float)bitcount[i]/rounds;
 	delta = fabs(ratio-0.5f);
@@ -96,42 +97,119 @@ static float print_bitcount(void)
     }
     printf("  Worst: %.4f\n", worst);
     if(worst>MAX_WORST_ALLOWED) result++;
+}
+
+static float worst_bitcount(void)
+{
+    int i;
+    float worst = 0.0f;
+
+    for(i=0;i<16;i++)
+    {
+        float ratio;
+	float delta;
+        ratio=(float)bitcount[i]/rounds;
+	delta = fabs(ratio-0.5f);
+        if(delta > worst)
+            worst=delta;
+    }
     return worst;
 }
 
+static void run_one(void)
+{
+    float worst[4];
+    memset(worst, 0, sizeof(worst));
+
+    run_randomtest(classic);
+    worst[0] = worst_bitcount();
+
+    run_randomtest(simple);
+    worst[1] = worst_bitcount();
+
+    run_randomtest(simple2);
+    worst[2] = worst_bitcount();
+
+    run_randomtest(nr);
+    worst[3] = worst_bitcount();
+
+    /* fimd the best algo */
+    float minValue = worst[0];
+    int minIndex = 0;
+
+    for (int i = 1; i < 4; i++)
+    {
+       if (worst[i] < minValue)
+       {
+          minValue = worst[i];
+	  minIndex = i;
+       }
+    }
+
+    group[minIndex] += 1;
+}
+
+static void seed_rng(void)
+{
+#ifdef HAVE_SRANDOMDEV
+    srandomdev();
+#endif
+}
 
 int main(int argc,const char *argv[])
 {
     /* 100k rounds by default */
     rounds=100000;
+    /* 20 groups by default */
+    groups=20;
+
+    /* override counts from command line */
+    if(argc>2)
+    {
+        groups=atoi(argv[2]);
+    }
     if(argc>1)
     {
         rounds=atoi(argv[1]);
     }
 
-    printf("Running %d rounds.\n\n", rounds);
+    printf("Running %d groups of %d rounds.\n\n", groups, rounds);
 
     result=0;
-#ifdef HAVE_SRANDOMDEV
+    memset(group, 0, sizeof(group));
-    srandomdev();
-#endif
 
+    if ( groups == 1 )
+    {
+	seed_rng();
 	printf("Generator: classic\n");
 	run_randomtest(classic);
 	print_bitcount();
 
-    printf("Generator: simple\n");
+	printf("Generator: simple (low bits)\n");
 	run_randomtest(simple);
 	print_bitcount();
 
-    printf("Generator: simple2\n");
+	printf("Generator: simple2 (high bits)\n");
 	run_randomtest(simple2);
 	print_bitcount();
 
-    result=0;
 	printf("Generator: Numerical Recipes\n");
 	run_randomtest(nr);
 	print_bitcount();
+    } else {
+	int i;
+	for (i=0; i< groups; i++)
+	{
+	   seed_rng();
+	   run_one();
+	}
+
+	printf("Winning generators\n\n");
+	printf("Generator: classic %d\n", group[0]);
+	printf("Generator: simple (low bits) %d\n", group[1]);
+	printf("Generator: simple2 (high bits) %d\n", group[2]);
+	printf("Generator: Numerical Recipes %d\n", group[3]);
+    }
 
     return result;
 }