diff --git a/ChangeLog b/ChangeLog
index 4f0131cf58..246514f080 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Jul 18 09:16:18 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* random.c (rb_random_{int32,real,bytes,int}): added functions for
+	  extension libraries.
+
 Sat Jul 18 09:07:00 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* random.c (fill_random_seed): use cryptographic service on Windows.
diff --git a/include/ruby/intern.h b/include/ruby/intern.h
index 7375442b41..4418806a6b 100644
--- a/include/ruby/intern.h
+++ b/include/ruby/intern.h
@@ -524,9 +524,13 @@ VALUE rb_range_new(VALUE, VALUE, int);
 VALUE rb_range_beg_len(VALUE, long*, long*, long, int);
 int rb_range_values(VALUE range, VALUE *begp, VALUE *endp, int *exclp);
 /* random.c */
-unsigned long rb_genrand_int32(void);
+unsigned int rb_genrand_int32(void);
 double rb_genrand_real(void);
 void rb_reset_random_seed(void);
+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);
 /* re.c */
 #define rb_memcmp memcmp
 int rb_memcicmp(const void*,const void*,long);
diff --git a/random.c b/random.c
index 57ab673831..ceec247fa1 100644
--- a/random.c
+++ b/random.c
@@ -211,7 +211,7 @@ struct Random {
 
 static struct Random default_rand;
 
-unsigned long
+unsigned int
 rb_genrand_int32(void)
 {
     return genrand_int32(&default_rand.rnd.mt);
@@ -767,6 +767,20 @@ rb_rand_internal(unsigned long i)
     return limited_rand(mt, i);
 }
 
+unsigned int
+rb_random_int32(VALUE obj)
+{
+    rb_random_t *rnd = get_rnd(obj);
+    return genrand_int32(&rnd->mt);
+}
+
+double
+rb_random_real(VALUE obj)
+{
+    rb_random_t *rnd = get_rnd(obj);
+    return genrand_real(&rnd->mt);
+}
+
 /*
  * call-seq: prng.bytes(size) -> prng
  *
@@ -775,9 +789,14 @@ rb_rand_internal(unsigned long i)
  */
 static VALUE
 random_bytes(VALUE obj, VALUE len)
+{
+    return rb_random_bytes(obj, FIX2LONG(rb_to_int(len)));
+}
+
+VALUE
+rb_random_bytes(VALUE obj, long n)
 {
     rb_random_t *rnd = get_rnd(obj);
-    long n = FIX2LONG(rb_to_int(len));
     VALUE bytes = rb_str_new(0, n);
     char *ptr = RSTRING_PTR(bytes);
     unsigned int r, i;
@@ -868,8 +887,8 @@ rand_int(struct MT *mt, VALUE vmax)
  *
  * Otherwise, it raises an ArgumentError.
  */
-static VALUE
-random_int(VALUE obj, VALUE vmax)
+VALUE
+rb_random_int(VALUE obj, VALUE vmax)
 {
     VALUE v, beg = Qundef;
     rb_random_t *rnd = get_rnd(obj);
@@ -887,6 +906,8 @@ random_int(VALUE obj, VALUE vmax)
     return add_to_begin(beg, v);
 }
 
+#define random_int rb_random_int
+
 /*
  * call-seq:
  *     prng.float -> float