4 files changed, 21 insertions, 7 deletions
diff --git a/ChangeLog b/ChangeLog
index 074ecef985..01c46b56c2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+Fri Sep 10 10:33:18 2010  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* random.c (rb_genrand_ulong_limited): renamed from
+	  rb_rand_internal and now this is public API.
+
+	* include/ruby/ruby.h (rb_genrand_ulong_limited): added.
+
+	* bignum.c (big_sparse_p): use rb_genrand_ulong_limited.
+
 Fri Sep 10 13:07:22 2010  NAKAMURA, Hiroshi  <nahi@ruby-lang.org>
 
 	* ext/digest/lib/digest.rb: removed unused exception variable
diff --git a/bignum.c b/bignum.c
index 1dd43df494..3145f24843 100644
--- a/bignum.c
+++ b/bignum.c
@@ -2214,11 +2214,10 @@ static inline VALUE
 big_sparse_p(VALUE x)
 {
     long c = 0, n = RBIGNUM_LEN(x);
-    unsigned long rb_rand_internal(unsigned long i);
 
-    if (          BDIGITS(x)[rb_rand_internal(n / 2) + n / 4]) c++;
-    if (c <= 1 && BDIGITS(x)[rb_rand_internal(n / 2) + n / 4]) c++;
-    if (c <= 1 && BDIGITS(x)[rb_rand_internal(n / 2) + n / 4]) c++;
+    if (          BDIGITS(x)[rb_genrand_ulong_limited(n / 2) + n / 4]) c++;
+    if (c <= 1 && BDIGITS(x)[rb_genrand_ulong_limited(n / 2) + n / 4]) c++;
+    if (c <= 1 && BDIGITS(x)[rb_genrand_ulong_limited(n / 2) + n / 4]) c++;
 
     return (c <= 1) ? Qtrue : Qfalse;
 }
diff --git a/include/ruby/intern.h b/include/ruby/intern.h
index 0ae4d47157..2c79d700de 100644
--- a/include/ruby/intern.h
+++ b/include/ruby/intern.h
@@ -559,6 +559,7 @@ VALUE rb_random_bytes(VALUE rnd, long n);
 VALUE rb_random_int(VALUE rnd, VALUE max);
 unsigned int rb_random_int32(VALUE rnd);
 double rb_random_real(VALUE rnd);
+unsigned long rb_genrand_ulong_limited(unsigned long i);
 /* re.c */
 #define rb_memcmp memcmp
 int rb_memcicmp(const void*,const void*,long);
diff --git a/random.c b/random.c
index 64b1cec4b1..9044c77432 100644
--- a/random.c
+++ b/random.c
@@ -875,11 +875,16 @@ limited_big_rand(struct MT *mt, struct RBignum *limit)
     return rb_big_norm((VALUE)val);
 }
 
+/*
+ * Returns random unsigned long value in [0, _limit_].
+ *
+ * Note that _limit_ is included, and the range of the argument and the
+ * return value depends on environments.
+ */
 unsigned long
-rb_rand_internal(unsigned long i)
+rb_genrand_ulong_limited(unsigned long limit)
 {
-    struct MT *mt = default_mt();
-    return limited_rand(mt, i);
+    return limited_rand(default_mt(), limit);
 }
 
 unsigned int