1 files changed, 85 insertions, 37 deletions

diff --git a/random.c b/random.c
index d0a5756b69..7b57d472cd 100644
--- a/random.c
+++ b/random.c
@@ -6,17 +6,80 @@
   $Date$
   created at: Fri Dec 24 16:39:21 JST 1993
 
-  Copyright (C) 1993-1996 Yukihiro Matsumoto
+  Copyright (C) 1993-1998 Yukihiro Matsumoto
 
 ************************************************/
 
 #include "ruby.h"
 
+#include <time.h>
+#ifndef NT
+#ifdef HAVE_SYS_TIME_H
+# include <sys/time.h>
+#else
+struct timeval {
+        long    tv_sec;         /* seconds */
+        long    tv_usec;        /* and microseconds */
+};
+#endif
+#endif /* NT */
+
+#ifdef HAVE_STDLIB_H
+# include <stdlib.h>
+#endif
+
+/*
+ * Prefer to use drand48, otherwise use random, or rand as a last resort.
+ */
+#ifdef HAVE_DRAND48
+
+#ifndef HAVE_DRAND48_DECL
+double drand48 _((void));
+void srand48 _((long));
+#endif
+
+#define SRANDOM(s)	srand48((long)(s))
+#define RANDOM_NUMBER	drand48()
+
+#else /* not HAVE_DRAND48 */
+
+/*
+ * The largest number returned by the random number generator is
+ * RANDOM_MAX.  If we're using `rand' it's RAND_MAX, but if we're
+ * using `random' it's 2^31-1.
+ */
+#ifndef RANDOM_MAX
+# ifndef HAVE_RANDOM
+#  define RANDOM_MAX	RAND_MAX
+# else
+#  define RANDOM_MAX	2147483647.0
+# endif
+#endif
+
+#ifdef HAVE_RANDOM
+
+#define RANDOM	random
+#define SRANDOM	srandom
+
+#else /* HAVE_RANDOM */
+
+#define RANDOM	rand
+#define SRANDOM	srand
+
+#endif /* HAVE_RANDOM */
+
+/* 0 <= RANDOM_NUMBER <= 1 */
+#define RANDOM_NUMBER (((double)RANDOM())/(double)RANDOM_MAX)
+
+#endif /* not HAVE_DRAND48 */
+
+#ifdef HAVE_RANDOM
 static int first = 1;
 static char state[256];
+#endif
 
 static VALUE
-f_srand(argc, argv, obj)
+rb_f_srand(argc, argv, obj)
     int argc;
     VALUE *argv;
     VALUE obj;
@@ -26,10 +89,13 @@ f_srand(argc, argv, obj)
     static int saved_seed;
 
     if (rb_scan_args(argc, argv, "01", &seed) == 0) {
-	seed = time(0);
+	struct timeval tv;
+
+	gettimeofday(&tv, 0);
+	seed = tv.tv_sec ^ tv.tv_usec;
     }
     else {
-	seed = NUM2INT(seed);
+	seed = NUM2UINT(seed);
     }
 
 #ifdef HAVE_RANDOM
@@ -40,62 +106,44 @@ f_srand(argc, argv, obj)
     else {
 	setstate(state);
     }
+#endif
 
-    srandom(seed);
-    old = saved_seed;
-    saved_seed = seed;
-
-    return int2inum(old);
-#else
-    srand(seed);
+    SRANDOM(seed);
     old = saved_seed;
     saved_seed = seed;
 
-    return int2inum(old);
-#endif
+    return rb_int2inum(old);
 }
 
 static VALUE
-f_rand(obj, vmax)
+rb_f_rand(obj, vmax)
     VALUE obj, vmax;
 {
-    int val, max;
-
-#ifdef HAVE_RANDOM
-    if (first == 1) {
-	initstate(1, state, sizeof state);
-	first = 0;
-    }
-#endif
+    long val, max;
 
     switch (TYPE(vmax)) {
       case T_BIGNUM:
-	return big_rand(vmax);
+	return rb_big_rand(vmax);
 	
       case T_FLOAT:
 	if (RFLOAT(vmax)->value > LONG_MAX || RFLOAT(vmax)->value < LONG_MIN)
-	    return big_rand(dbl2big(RFLOAT(vmax)->value));
+	    return rb_big_rand(rb_dbl2big(RFLOAT(vmax)->value));
 	break;
     }
 
-    max = NUM2INT(vmax);
-    if (max == 0) ArgError("rand(0)");
-
-#ifdef HAVE_RANDOM
-    val = random() % max;
-#else
-    val = rand() % max;
-#endif
+    max = NUM2LONG(vmax);
+    if (max == 0) {
+	return rb_float_new(RANDOM_NUMBER);
+    }
+    val = max*RANDOM_NUMBER;
 
     if (val < 0) val = -val;
-    return int2inum(val);
+    return rb_int2inum(val);
 }
 
 void
 Init_Random()
 {
-    extern VALUE mKernel;
-
-    rb_define_global_function("srand", f_srand, -1);
-    rb_define_global_function("rand", f_rand, 1);
+    rb_define_global_function("srand", rb_f_srand, -1);
+    rb_define_global_function("rand", rb_f_rand, 1);
 }