1 files changed, 224 insertions, 107 deletions

diff --git a/mrbgems/mruby-random/src/random.c b/mrbgems/mruby-random/src/random.c
index 1c89ca21d..8f983ea0f 100644
--- a/mrbgems/mruby-random/src/random.c
+++ b/mrbgems/mruby-random/src/random.c
@@ -6,95 +6,42 @@
 
 #include "mruby.h"
 #include "mruby/variable.h"
+#include "mruby/class.h"
 #include "mruby/data.h"
+#include "mruby/array.h"
 #include "mt19937ar.h"
 
 #include <time.h>
 
-#define GLOBAL_RAND_SEED_KEY          "$mrb_g_rand_seed"
-#define GLOBAL_RAND_SEED_KEY_CSTR_LEN 16
-
-#define INSTANCE_RAND_SEED_KEY          "$mrb_i_rand_seed"
-#define INSTANCE_RAND_SEED_KEY_CSTR_LEN 16
-
-#define MT_STATE_KEY          "$mrb_i_mt_state"
-#define MT_STATE_KEY_CSTR_LEN 15
+static char const MT_STATE_KEY[] = "$mrb_i_mt_state";
 
 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 = (mt_state*)mrb_data_get_ptr(mrb, context, &mt_state_type);
-  if (!t)
-    mrb_raise(mrb, E_RUNTIME_ERROR, "mt_state get from mrb_iv_get failed");
-
-  return t;
-}
-
-static void mt_g_srand(unsigned long seed)
-{
-  init_genrand(seed);
-}
-
-static unsigned long mt_g_rand()
-{
-  return genrand_int32();
-}
-
-static double mt_g_rand_real()
-{
-  return genrand_real1();
-}
-
-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());
-    if (mrb_fixnum(seed) < 0) {
-      seed = mrb_fixnum_value( 0 - mrb_fixnum(seed));
-    }
-  }
-
-  mt_g_srand((unsigned) mrb_fixnum(seed));
-
-  return seed;
-}
-
-static mrb_value mrb_random_mt_g_rand(mrb_state *mrb, mrb_value max)
-{
-  mrb_value value;
-
-  if (mrb_fixnum(max) == 0) {
-    value = mrb_float_value(mrb, mt_g_rand_real());
-  } else {
-    value = mrb_fixnum_value(mt_g_rand() % mrb_fixnum(max));
-  }
+static mrb_value mrb_random_rand(mrb_state *mrb, mrb_value self);
+static mrb_value mrb_random_srand(mrb_state *mrb, mrb_value self);
 
-  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));
@@ -108,24 +55,27 @@ 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;
 
   if (mrb_fixnum(max) == 0) {
     value = mrb_float_value(mrb, mt_rand_real(t));
-  } else {
+  }
+  else {
     value = mrb_fixnum_value(mt_rand(t) % mrb_fixnum(max));
   }
 
   return value;
 }
 
-static mrb_value get_opt(mrb_state* mrb)
+static mrb_value 
+get_opt(mrb_state* mrb)
 {
   mrb_value arg;
 
-  arg = mrb_fixnum_value(0);
+  arg = mrb_nil_value();
   mrb_get_args(mrb, "|o", &arg);
 
   if (!mrb_nil_p(arg)) {
@@ -140,92 +90,259 @@ static mrb_value get_opt(mrb_state* mrb)
   return arg;
 }
 
-static mrb_value mrb_random_g_rand(mrb_state *mrb, mrb_value self)
-{
-  mrb_value max;
-  mrb_value seed;
+static mrb_value
+get_random(mrb_state *mrb) {
+  return mrb_const_get(mrb,
+             mrb_obj_value(mrb_class_get(mrb, "Random")),
+             mrb_intern_lit(mrb, "DEFAULT"));
+}
 
-  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());
-  }
-  return mrb_random_mt_g_rand(mrb, max);
+static mt_state *
+get_random_state(mrb_state *mrb)
+{
+  mrb_value random_val = get_random(mrb);
+  return DATA_GET_PTR(mrb, random_val, &mt_state_type, mt_state);
 }
 
-static mrb_value mrb_random_g_srand(mrb_state *mrb, mrb_value self)
+static mrb_value 
+mrb_random_g_rand(mrb_state *mrb, mrb_value self)
 {
-  mrb_value seed;
-  mrb_value old_seed;
+  mrb_value random = get_random(mrb);
+  return mrb_random_rand(mrb, random);
+}
 
-  seed = get_opt(mrb);
-  seed = mrb_random_mt_g_srand(mrb, seed);
-  old_seed = mrb_gv_get(mrb, mrb_intern2(mrb, GLOBAL_RAND_SEED_KEY, GLOBAL_RAND_SEED_KEY_CSTR_LEN));
-  mrb_gv_set(mrb, mrb_intern2(mrb, GLOBAL_RAND_SEED_KEY, GLOBAL_RAND_SEED_KEY_CSTR_LEN), seed);
-  return old_seed;
+static mrb_value 
+mrb_random_g_srand(mrb_state *mrb, mrb_value self)
+{
+  mrb_value random = get_random(mrb);
+  return mrb_random_srand(mrb, random);
 }
 
-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 = (mt_state *)mrb_malloc(mrb, sizeof(mt_state));
+  mt_state *t;
+  
+  /* avoid memory leaks */
+  t = (mt_state*)DATA_PTR(self);
+  if (t) {
+    mrb_free(mrb, t);
+  }  
+
+  DATA_TYPE(self) = &mt_state_type;
+  DATA_PTR(self) = NULL;
+  
+  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)));
+  if (mrb_nil_p(seed)) {
+    t->has_seed = FALSE;
+  }
+  else {
+    mrb_assert(mrb_fixnum_p(seed));
+    t->has_seed = TRUE;
+    t->seed = mrb_fixnum(seed);
+  }
+  
+  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, mt_state *t)
+{
+  if (!t->has_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;
-  mrb_value seed;
-  mt_state *t = mrb_mt_get_context(mrb, self);
+  mt_state *t = DATA_GET_PTR(mrb, self, &mt_state_type, mt_state);
 
   max = get_opt(mrb);
-  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());
-  }
+  mrb_random_rand_seed(mrb, t);
   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_GET_PTR(mrb, self, &mt_state_type, mt_state);
 
   seed = get_opt(mrb);
   seed = mrb_random_mt_srand(mrb, t, seed);
-  old_seed = mrb_iv_get(mrb, self, mrb_intern2(mrb, INSTANCE_RAND_SEED_KEY, INSTANCE_RAND_SEED_KEY_CSTR_LEN));
-  mrb_iv_set(mrb, self, mrb_intern2(mrb, INSTANCE_RAND_SEED_KEY, INSTANCE_RAND_SEED_KEY_CSTR_LEN), seed);
+  old_seed = t->has_seed? mrb_fixnum_value(t->seed) : mrb_nil_value();
+  if (mrb_nil_p(seed)) {
+    t->has_seed = FALSE;
+  }
+  else {
+    mrb_assert(mrb_fixnum_p(seed));
+    t->has_seed = TRUE;
+    t->seed = mrb_fixnum(seed);
+  }
 
   return old_seed;
 }
 
+/*
+ *  call-seq:
+ *     ary.shuffle!   ->   ary
+ *
+ *  Shuffles elements in self in place.
+ */
+
+static mrb_value
+mrb_ary_shuffle_bang(mrb_state *mrb, mrb_value ary)
+{
+  mrb_int i;
+  mt_state *random = NULL;
+  
+  if (RARRAY_LEN(ary) > 1) {
+    mrb_get_args(mrb, "|d", &random, &mt_state_type);
+
+    if (random == NULL) {
+      random = get_random_state(mrb);
+    }
+    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_value tmp;
+      
+      j = mrb_fixnum(mrb_random_mt_rand(mrb, random, mrb_fixnum_value(RARRAY_LEN(ary))));
+      
+      tmp = RARRAY_PTR(ary)[i];
+      RARRAY_PTR(ary)[i] = RARRAY_PTR(ary)[j];
+      RARRAY_PTR(ary)[j] = tmp;
+    }    
+  }
+  
+  return ary;
+}
+
+/*
+ *  call-seq:
+ *     ary.shuffle   ->   new_ary
+ *
+ *  Returns a new array with elements of self shuffled.
+ */
+
+static mrb_value
+mrb_ary_shuffle(mrb_state *mrb, mrb_value ary)
+{
+  mrb_value new_ary = mrb_ary_new_from_values(mrb, RARRAY_LEN(ary), RARRAY_PTR(ary));
+  mrb_ary_shuffle_bang(mrb, new_ary);
+  
+  return new_ary;
+}
+
+/*
+ *  call-seq:
+ *     ary.sample      ->   obj
+ *     ary.sample(n)   ->   new_ary
+ *
+ *  Choose a random element or +n+ random elements from the array.
+ *
+ *  The elements are chosen by using random and unique indices into the array
+ *  in order to ensure that an element doesn't repeat itself unless the array
+ *  already contained duplicate elements.
+ *
+ *  If the array is empty the first form returns +nil+ and the second form
+ *  returns an empty array.
+ */
+
+static mrb_value
+mrb_ary_sample(mrb_state *mrb, mrb_value ary)
+{
+  mrb_int n = 0;
+  mrb_bool given;
+  mt_state *random = NULL;
+  mrb_int len = RARRAY_LEN(ary);
+
+  mrb_get_args(mrb, "|i?d", &n, &given, &random, &mt_state_type);
+  if (random == NULL) {
+    random = get_random_state(mrb); 
+  }
+  mrb_random_rand_seed(mrb, random);
+  mt_rand(random);
+  if (!given) {                 /* pick one element */
+    switch (len) {
+    case 0:
+      return mrb_nil_value();
+    case 1:
+      return RARRAY_PTR(ary)[0];
+    default:
+      return RARRAY_PTR(ary)[mt_rand(random) % len];
+    }
+  }
+  else {
+    mrb_value result;
+    mrb_int i, j;
+
+    if (n < 0) mrb_raise(mrb, E_ARGUMENT_ERROR, "negative sample number");
+    if (n > len) n = len;
+    result = mrb_ary_new_capa(mrb, n);
+    for (i=0; i<n; i++) {
+      mrb_int r;
+
+      for (;;) {
+      retry:
+        r = mt_rand(random) % len;
+
+        for (j=0; j<i; j++) {
+          if (mrb_fixnum(RARRAY_PTR(result)[j]) == r) {
+            goto retry;         /* retry if duplicate */
+          }
+        }
+        break;
+      }
+      RARRAY_PTR(result)[i] = mrb_fixnum_value(r);
+      RARRAY_LEN(result)++;
+    }
+    for (i=0; i<n; i++) {
+      RARRAY_PTR(result)[i] = RARRAY_PTR(ary)[mrb_fixnum(RARRAY_PTR(result)[i])];
+    }
+    return result;
+  }
+}
+
+
 void mrb_mruby_random_gem_init(mrb_state *mrb)
 {
   struct RClass *random;
+  struct RClass *array = mrb->array_class;
 
   mrb_define_method(mrb, mrb->kernel_module, "rand", mrb_random_g_rand, MRB_ARGS_OPT(1));
   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));
 
   mrb_define_method(mrb, random, "initialize", mrb_random_init, MRB_ARGS_OPT(1));
   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_OPT(1));
+  mrb_define_method(mrb, array, "shuffle!", mrb_ary_shuffle_bang, MRB_ARGS_OPT(1));
+  mrb_define_method(mrb, array, "sample", mrb_ary_sample, MRB_ARGS_OPT(2));
+
+  mrb_const_set(mrb, mrb_obj_value(random), mrb_intern_lit(mrb, "DEFAULT"),
+          mrb_obj_new(mrb, random, 0, NULL));
 }
 
 void mrb_mruby_random_gem_final(mrb_state *mrb)
 {
 }
-