Added support for Random as an argument to shuffle and shuffle!. Refactored random gem to use DATA instance type and hold mt_state inside the DATA_PTR instead of in an instance variable.

mrbgems/mruby-random/src/random.c

@@ -6,6 +6,7 @@
 
 #include "mruby.h"
 #include "mruby/variable.h"
+#include "mruby/class.h"
 #include "mruby/data.h"
 #include "mruby/array.h"
 #include "mt19937ar.h"
@@ -19,23 +20,11 @@
 #define INSTANCE_RAND_SEED_KEY_CSTR_LEN 16
 
 #define MT_STATE_KEY          "$mrb_i_mt_state"
-#define MT_STATE_KEY_CSTR_LEN 15
 
 static const struct mrb_data_type mt_state_type = {
   MT_STATE_KEY, mrb_free,
 };
 
-static mt_state *mrb_mt_get_context(mrb_state *mrb,  mrb_value self)
-{
-  mt_state *t;
-  mrb_value context;
-
-  context = mrb_iv_get(mrb, self, mrb_intern2(mrb, MT_STATE_KEY, MT_STATE_KEY_CSTR_LEN));
-  t = DATA_GET_PTR(mrb, context, &mt_state_type, mt_state);
-
-  return t;
-}
-
 static void mt_g_srand(unsigned long seed)
 {
   init_genrand(seed);
@@ -51,7 +40,8 @@ static double mt_g_rand_real()
   return genrand_real1();
 }
 
-static mrb_value mrb_random_mt_g_srand(mrb_state *mrb, mrb_value seed)
+static mrb_value 
+mrb_random_mt_g_srand(mrb_state *mrb, mrb_value seed)
 {
   if (mrb_nil_p(seed)) {
     seed = mrb_fixnum_value(time(NULL) + mt_g_rand());
@@ -65,7 +55,8 @@ static mrb_value mrb_random_mt_g_srand(mrb_state *mrb, mrb_value seed)
   return seed;
 }
 
-static mrb_value mrb_random_mt_g_rand(mrb_state *mrb, mrb_value max)
+static mrb_value 
+mrb_random_mt_g_rand(mrb_state *mrb, mrb_value max)
 {
   mrb_value value;
 
@@ -78,22 +69,26 @@ static mrb_value mrb_random_mt_g_rand(mrb_state *mrb, mrb_value max)
   return value;
 }
  
-static void mt_srand(mt_state *t, unsigned long seed)
+static void 
+mt_srand(mt_state *t, unsigned long seed)
 {
   mrb_random_init_genrand(t, seed);
 }  
 
-static unsigned long mt_rand(mt_state *t)
+static unsigned long 
+mt_rand(mt_state *t)
 {
   return mrb_random_genrand_int32(t);
 }  
 
-static double mt_rand_real(mt_state *t)
+static double 
+mt_rand_real(mt_state *t)
 {
   return mrb_random_genrand_real1(t);
 }  
 
-static mrb_value mrb_random_mt_srand(mrb_state *mrb, mt_state *t, mrb_value seed)
+static mrb_value 
+mrb_random_mt_srand(mrb_state *mrb, mt_state *t, mrb_value seed)
 { 
   if (mrb_nil_p(seed)) {
     seed = mrb_fixnum_value(time(NULL) + mt_rand(t));
@@ -107,7 +102,8 @@ static mrb_value mrb_random_mt_srand(mrb_state *mrb, mt_state *t, mrb_value seed
   return seed;
 }
 
-static mrb_value mrb_random_mt_rand(mrb_state *mrb, mt_state *t, mrb_value max)
+static mrb_value 
+mrb_random_mt_rand(mrb_state *mrb, mt_state *t, mrb_value max)
 { 
   mrb_value value;
 
@@ -120,7 +116,8 @@ static mrb_value mrb_random_mt_rand(mrb_state *mrb, mt_state *t, mrb_value max)
   return value;
 }
 
-static mrb_value get_opt(mrb_state* mrb)
+static mrb_value 
+get_opt(mrb_state* mrb)
 {
   mrb_value arg;
 
@@ -139,20 +136,29 @@ static mrb_value get_opt(mrb_state* mrb)
   return arg;
 }
 
-static mrb_value mrb_random_g_rand(mrb_state *mrb, mrb_value self)
+static void 
+mrb_random_g_rand_seed(mrb_state *mrb) 
 {
-  mrb_value max;
   mrb_value seed;
-
-  max = get_opt(mrb);
+  
   seed = mrb_gv_get(mrb, mrb_intern2(mrb, GLOBAL_RAND_SEED_KEY, GLOBAL_RAND_SEED_KEY_CSTR_LEN));
   if (mrb_nil_p(seed)) {
     mrb_random_mt_g_srand(mrb, mrb_nil_value());
   }
+}
+
+static mrb_value 
+mrb_random_g_rand(mrb_state *mrb, mrb_value self)
+{
+  mrb_value max;
+
+  max = get_opt(mrb);
+  mrb_random_g_rand_seed(mrb);
   return mrb_random_mt_g_rand(mrb, max);
 }
 
-static mrb_value mrb_random_g_srand(mrb_state *mrb, mrb_value self)
+static mrb_value 
+mrb_random_g_srand(mrb_state *mrb, mrb_value self)
 {
   mrb_value seed;
   mrb_value old_seed;
@@ -164,41 +170,62 @@ static mrb_value mrb_random_g_srand(mrb_state *mrb, mrb_value self)
   return old_seed;
 }
 
-static mrb_value mrb_random_init(mrb_state *mrb, mrb_value self)
+static mrb_value 
+mrb_random_init(mrb_state *mrb, mrb_value self)
 {
   mrb_value seed;
+  mt_state *t;
+  
+  DATA_TYPE(self) = &mt_state_type;
+  DATA_PTR(self) = NULL;
+  
+  /* avoid memory leaks */
+  t = (mt_state*)DATA_PTR(self);
+  if (t) {
+    mrb_free(mrb, t);
+  }  
 
-
-  mt_state *t = (mt_state *)mrb_malloc(mrb, sizeof(mt_state));
+  t = (mt_state *)mrb_malloc(mrb, sizeof(mt_state));
   t->mti = N + 1;
 
   seed = get_opt(mrb);
   seed = mrb_random_mt_srand(mrb, t, seed);
   mrb_iv_set(mrb, self, mrb_intern2(mrb, INSTANCE_RAND_SEED_KEY, INSTANCE_RAND_SEED_KEY_CSTR_LEN), seed);
-  mrb_iv_set(mrb, self, mrb_intern2(mrb, MT_STATE_KEY, MT_STATE_KEY_CSTR_LEN),
-    mrb_obj_value(Data_Wrap_Struct(mrb, mrb->object_class, &mt_state_type, (void*) t)));
+  
+  DATA_PTR(self) = t;
+  
   return self;
 }
 
-static mrb_value mrb_random_rand(mrb_state *mrb, mrb_value self)
+static void 
+mrb_random_rand_seed(mrb_state *mrb, mrb_value self)
 {
-  mrb_value max;
   mrb_value seed;
-  mt_state *t = mrb_mt_get_context(mrb, self);
-
-  max = get_opt(mrb);
+  mt_state *t = DATA_PTR(self);
+  
   seed = mrb_iv_get(mrb, self, mrb_intern2(mrb, INSTANCE_RAND_SEED_KEY, INSTANCE_RAND_SEED_KEY_CSTR_LEN));
   if (mrb_nil_p(seed)) {
     mrb_random_mt_srand(mrb, t, mrb_nil_value());
   }
+}
+
+static mrb_value 
+mrb_random_rand(mrb_state *mrb, mrb_value self)
+{
+  mrb_value max;
+  mt_state *t = DATA_PTR(self);
+
+  max = get_opt(mrb);
+  mrb_random_rand_seed(mrb, self);
   return mrb_random_mt_rand(mrb, t, max);
 }
 
-static mrb_value mrb_random_srand(mrb_state *mrb, mrb_value self)
+static mrb_value 
+mrb_random_srand(mrb_state *mrb, mrb_value self)
 {
   mrb_value seed;
   mrb_value old_seed;
-  mt_state *t = mrb_mt_get_context(mrb, self);
+  mt_state *t = DATA_PTR(self);
 
   seed = get_opt(mrb);
   seed = mrb_random_mt_srand(mrb, t, seed);
@@ -219,17 +246,29 @@ static mrb_value
 mrb_ary_shuffle_bang(mrb_state *mrb, mrb_value ary)
 {
   mrb_int i;
-  mrb_value seed;
-
-  seed = mrb_gv_get(mrb, mrb_intern2(mrb, GLOBAL_RAND_SEED_KEY, GLOBAL_RAND_SEED_KEY_CSTR_LEN));
-  if (mrb_nil_p(seed)) {
-    mrb_random_mt_g_srand(mrb, mrb_nil_value());
-  }
+  mrb_value random = mrb_nil_value();
   
   if (RARRAY_LEN(ary) > 1) {
+    mrb_get_args(mrb, "|o", &random);
+
+    if( mrb_nil_p(random) ) {
+      mrb_random_g_rand_seed(mrb);
+    } else {
+      mrb_data_check_type(mrb, random, &mt_state_type);
+      mrb_random_rand_seed(mrb, random);
+    }
+  
     mrb_ary_modify(mrb, mrb_ary_ptr(ary));
+    
     for (i = RARRAY_LEN(ary) - 1; i > 0; i--)  {
-      mrb_int j = mrb_fixnum(mrb_random_mt_g_rand(mrb, mrb_fixnum_value(RARRAY_LEN(ary))));
+      mrb_int j;
+      
+      if( mrb_nil_p(random) ) {
+        j = mrb_fixnum(mrb_random_mt_g_rand(mrb, mrb_fixnum_value(RARRAY_LEN(ary))));
+      } else {
+        j = mrb_fixnum(mrb_random_mt_rand(mrb, DATA_PTR(random), mrb_fixnum_value(RARRAY_LEN(ary))));
+      }
+      
       mrb_value t = RARRAY_PTR(ary)[i];
       RARRAY_PTR(ary)[i] = RARRAY_PTR(ary)[j];
       RARRAY_PTR(ary)[j] = t;
@@ -264,6 +303,7 @@ void mrb_mruby_random_gem_init(mrb_state *mrb)
   mrb_define_method(mrb, mrb->kernel_module, "srand", mrb_random_g_srand, MRB_ARGS_OPT(1));
 
   random = mrb_define_class(mrb, "Random", mrb->object_class);
+  MRB_SET_INSTANCE_TT(random, MRB_TT_DATA);
   mrb_define_class_method(mrb, random, "rand", mrb_random_g_rand, MRB_ARGS_OPT(1));
   mrb_define_class_method(mrb, random, "srand", mrb_random_g_srand, MRB_ARGS_OPT(1));
 
@@ -271,8 +311,8 @@ void mrb_mruby_random_gem_init(mrb_state *mrb)
   mrb_define_method(mrb, random, "rand", mrb_random_rand, MRB_ARGS_OPT(1));
   mrb_define_method(mrb, random, "srand", mrb_random_srand, MRB_ARGS_OPT(1));
   
-  mrb_define_method(mrb, array, "shuffle", mrb_ary_shuffle, MRB_ARGS_NONE());
-  mrb_define_method(mrb, array, "shuffle!", mrb_ary_shuffle_bang, MRB_ARGS_NONE());
+  mrb_define_method(mrb, array, "shuffle", mrb_ary_shuffle, MRB_ARGS_OPT(1));
+  mrb_define_method(mrb, array, "shuffle!", mrb_ary_shuffle_bang, MRB_ARGS_OPT(1));
 }
 
 void mrb_mruby_random_gem_final(mrb_state *mrb)

mrbgems/mruby-random/test/random.rb

@@ -43,4 +43,34 @@ assert('Array#shuffle!') do
   ary.shuffle!
   
   ary != [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] and 10.times { |x| ary.include? x }
+end
+
+assert("Array#shuffle(random)") do 
+  assert_raise(TypeError) do
+    # this will cause an exception due to the wrong argument
+    [1, 2].shuffle "Not a Random instance"
+  end
+  
+  # verify that the same seed causes the same results
+  ary1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+  shuffle1 = ary1.shuffle Random.new 345
+  ary2 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+  shuffle2 = ary2.shuffle Random.new 345
+  
+  ary1 != shuffle1 and 10.times { |x| shuffle1.include? x } and shuffle1 == shuffle2
+end
+
+assert('Array#shuffle!(random)') do
+  assert_raise(TypeError) do
+    # this will cause an exception due to the wrong argument
+    [1, 2].shuffle! "Not a Random instance"
+  end
+    
+  # verify that the same seed causes the same results
+  ary1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+  ary1.shuffle! Random.new 345
+  ary2 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+  ary2.shuffle! Random.new 345
+  
+  ary1 != [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] and 10.times { |x| ary1.include? x } and ary1 == ary2
 end