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authornobu <nobu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2015-02-14 03:20:04 (GMT)
committernobu <nobu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2015-02-14 03:20:04 (GMT)
commitb1adbd14e5b197596636f927c03ff132299ab6b6 (patch)
tree587e44dc967e33e900c4d46fc3bd49697d79a718 /random.c
parent1f13a179d303c1470f3e76656d14d24cf035fff4 (diff)
random.c: rand_random_number
* random.c (rand_random_number): add a method to return a random number like SecureRandom to Random::Formatter. * lib/securerandom.rb (random_bytes): move to Random::Formatter, the base method of the module. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49596 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'random.c')
-rw-r--r--random.c185
1 files changed, 135 insertions, 50 deletions
diff --git a/random.c b/random.c
index a4a3265..47246db 100644
--- a/random.c
+++ b/random.c
@@ -196,16 +196,26 @@ genrand_int32(struct MT *mt)
}
/* generates a random number on [0,1) with 53-bit resolution*/
+static double int_pair_to_real_exclusive(uint32_t a, uint32_t b);
static double
genrand_real(struct MT *mt)
{
/* mt must be initialized */
- unsigned int a = genrand_int32(mt)>>5, b = genrand_int32(mt)>>6;
+ unsigned int a = genrand_int32(mt), b = genrand_int32(mt);
+ return int_pair_to_real_exclusive(a, b);
+}
+
+static double
+int_pair_to_real_exclusive(uint32_t a, uint32_t b)
+{
+ a >>= 5;
+ b >>= 6;
return(a*67108864.0+b)*(1.0/9007199254740992.0);
}
/* generates a random number on [0,1] with 53-bit resolution*/
static double int_pair_to_real_inclusive(uint32_t a, uint32_t b);
+#if 0
static double
genrand_real2(struct MT *mt)
{
@@ -213,6 +223,7 @@ genrand_real2(struct MT *mt)
uint32_t a = genrand_int32(mt), b = genrand_int32(mt);
return int_pair_to_real_inclusive(a, b);
}
+#endif
/* These real versions are due to Isaku Wada, 2002/01/09 added */
@@ -839,10 +850,9 @@ rb_genrand_ulong_limited(unsigned long limit)
return limited_rand(default_mt(), limit);
}
-unsigned int
-rb_random_int32(VALUE obj)
+static unsigned int
+random_int32(VALUE obj, rb_random_t *rnd)
{
- rb_random_t *rnd = try_get_rnd(obj);
if (!rnd) {
#if SIZEOF_LONG * CHAR_BIT > 32
VALUE lim = ULONG2NUM(0x100000000UL);
@@ -856,6 +866,25 @@ rb_random_int32(VALUE obj)
return genrand_int32(&rnd->mt);
}
+unsigned int
+rb_random_int32(VALUE obj)
+{
+ return random_int32(obj, try_get_rnd(obj));
+}
+
+static double
+random_real(VALUE obj, rb_random_t *rnd, int excl)
+{
+ uint32_t a = random_int32(obj, rnd);
+ uint32_t b = random_int32(obj, rnd);
+ if (excl) {
+ return int_pair_to_real_exclusive(a, b);
+ }
+ else {
+ return int_pair_to_real_inclusive(a, b);
+ }
+}
+
double
rb_random_real(VALUE obj)
{
@@ -887,10 +916,9 @@ ulong_to_num_plus_1(unsigned long n)
#endif
}
-unsigned long
-rb_random_ulong_limited(VALUE obj, unsigned long limit)
+static unsigned long
+random_ulong_limited(VALUE obj, rb_random_t *rnd, unsigned long limit)
{
- rb_random_t *rnd = try_get_rnd(obj);
if (!rnd) {
extern int rb_num_negative_p(VALUE);
VALUE lim = ulong_to_num_plus_1(limit);
@@ -907,6 +935,32 @@ rb_random_ulong_limited(VALUE obj, unsigned long limit)
return limited_rand(&rnd->mt, limit);
}
+static VALUE
+random_ulong_limited_big(VALUE obj, rb_random_t *rnd, VALUE vmax)
+{
+ if (!rnd) {
+ extern int rb_num_negative_p(VALUE);
+ VALUE lim = rb_big_plus(vmax, INT2FIX(1));
+ VALUE v = rb_to_int(rb_funcall2(obj, id_rand, 1, &lim));
+ if (rb_num_negative_p(v)) {
+ rb_raise(rb_eRangeError, "random number too small %"PRIsVALUE, v);
+ }
+ if (FIX2LONG(rb_big_cmp(vmax, v)) < 0) {
+ rb_raise(rb_eRangeError, "random number too big %"PRIsVALUE, v);
+ }
+ return v;
+ }
+ return limited_big_rand(&rnd->mt, vmax);
+}
+
+unsigned long
+rb_random_ulong_limited(VALUE obj, unsigned long limit)
+{
+ return random_ulong_limited(obj, try_get_rnd(obj), limit);
+}
+
+static VALUE genrand_bytes(rb_random_t *rnd, long n);
+
/*
* call-seq: prng.bytes(size) -> a_string
*
@@ -918,21 +972,16 @@ rb_random_ulong_limited(VALUE obj, unsigned long limit)
static VALUE
random_bytes(VALUE obj, VALUE len)
{
- return rb_random_bytes(obj, NUM2LONG(rb_to_int(len)));
+ return genrand_bytes(get_rnd(obj), NUM2LONG(rb_to_int(len)));
}
-VALUE
-rb_random_bytes(VALUE obj, long n)
+static VALUE
+genrand_bytes(rb_random_t *rnd, long n)
{
- rb_random_t *rnd = try_get_rnd(obj);
VALUE bytes;
char *ptr;
unsigned int r, i;
- if (!rnd) {
- VALUE len = LONG2NUM(n);
- return rb_funcall2(obj, id_bytes, 1, &len);
- }
bytes = rb_str_new(0, n);
ptr = RSTRING_PTR(bytes);
for (; n >= SIZEOF_INT32; n -= SIZEOF_INT32) {
@@ -953,6 +1002,17 @@ rb_random_bytes(VALUE obj, long n)
return bytes;
}
+VALUE
+rb_random_bytes(VALUE obj, long n)
+{
+ rb_random_t *rnd = try_get_rnd(obj);
+ if (!rnd) {
+ VALUE len = LONG2NUM(n);
+ return rb_funcall2(obj, id_bytes, 1, &len);
+ }
+ return genrand_bytes(rnd, n);
+}
+
static VALUE
range_values(VALUE vmax, VALUE *begp, VALUE *endp, int *exclp)
{
@@ -967,20 +1027,19 @@ range_values(VALUE vmax, VALUE *begp, VALUE *endp, int *exclp)
}
static VALUE
-rand_int(struct MT *mt, VALUE vmax, int restrictive)
+rand_int(VALUE obj, rb_random_t *rnd, VALUE vmax, int restrictive)
{
/* mt must be initialized */
- long max;
unsigned long r;
if (FIXNUM_P(vmax)) {
- max = FIX2LONG(vmax);
+ long max = FIX2LONG(vmax);
if (!max) return Qnil;
if (max < 0) {
if (restrictive) return Qnil;
max = -max;
}
- r = limited_rand(mt, (unsigned long)max - 1);
+ r = random_ulong_limited(obj, rnd, (unsigned long)max - 1);
return ULONG2NUM(r);
}
else {
@@ -992,30 +1051,37 @@ rand_int(struct MT *mt, VALUE vmax, int restrictive)
}
vmax = rb_big_minus(vmax, INT2FIX(1));
if (FIXNUM_P(vmax)) {
- max = FIX2LONG(vmax);
+ long max = FIX2LONG(vmax);
if (max == -1) return Qnil;
- r = limited_rand(mt, max);
+ r = random_ulong_limited(obj, rnd, max);
return LONG2NUM(r);
}
- ret = limited_big_rand(mt, vmax);
+ ret = random_ulong_limited_big(obj, rnd, vmax);
RB_GC_GUARD(vmax);
return ret;
}
}
+NORETURN(static void domain_error(void));
+static void
+domain_error(void)
+{
+ VALUE error = INT2FIX(EDOM);
+ rb_exc_raise(rb_class_new_instance(1, &error, rb_eSystemCallError));
+}
+
static inline double
float_value(VALUE v)
{
double x = RFLOAT_VALUE(v);
if (isinf(x) || isnan(x)) {
- VALUE error = INT2FIX(EDOM);
- rb_exc_raise(rb_class_new_instance(1, &error, rb_eSystemCallError));
+ domain_error();
}
return x;
}
static inline VALUE
-rand_range(struct MT* mt, VALUE range)
+rand_range(VALUE obj, rb_random_t* rnd, VALUE range)
{
VALUE beg = Qundef, end = Qundef, vmax, v;
int excl = 0;
@@ -1029,7 +1095,7 @@ rand_range(struct MT* mt, VALUE range)
if (FIXNUM_P(vmax)) {
fixnum:
if ((max = FIX2LONG(vmax) - excl) >= 0) {
- unsigned long r = limited_rand(mt, (unsigned long)max);
+ unsigned long r = random_ulong_limited(obj, rnd, (unsigned long)max);
v = ULONG2NUM(r);
}
}
@@ -1039,7 +1105,7 @@ rand_range(struct MT* mt, VALUE range)
excl = 0;
goto fixnum;
}
- v = limited_big_rand(mt, vmax);
+ v = random_ulong_limited_big(obj, rnd, vmax);
}
}
else if (v = rb_check_to_float(vmax), !NIL_P(v)) {
@@ -1052,17 +1118,12 @@ rand_range(struct MT* mt, VALUE range)
mid = max + min;
max -= min;
}
- else {
- float_value(v);
+ else if (isnan(max)) {
+ domain_error();
}
v = Qnil;
if (max > 0.0) {
- if (excl) {
- r = genrand_real(mt);
- }
- else {
- r = genrand_real2(mt);
- }
+ r = random_real(obj, rnd, excl);
if (scale > 1) {
return rb_float_new(+(+(+(r - 0.5) * max) * scale) + mid);
}
@@ -1095,7 +1156,7 @@ rand_range(struct MT* mt, VALUE range)
return v;
}
-static VALUE rand_random(int argc, VALUE *argv, rb_random_t *rnd);
+static VALUE rand_random(int argc, VALUE *argv, VALUE obj, rb_random_t *rnd);
/*
* call-seq:
@@ -1129,16 +1190,17 @@ static VALUE rand_random(int argc, VALUE *argv, rb_random_t *rnd);
static VALUE
random_rand(int argc, VALUE *argv, VALUE obj)
{
- return rand_random(argc, argv, get_rnd(obj));
+ return rand_random(argc, argv, obj, get_rnd(obj));
}
static VALUE
-rand_random(int argc, VALUE *argv, rb_random_t *rnd)
+rand_random(int argc, VALUE *argv, VALUE obj, rb_random_t *rnd)
{
VALUE vmax, v;
+ double max = 0.0;
if (argc == 0) {
- return rb_float_new(genrand_real(&rnd->mt));
+ goto float_rand;
}
else {
rb_check_arity(argc, 0, 1);
@@ -1148,16 +1210,26 @@ rand_random(int argc, VALUE *argv, rb_random_t *rnd)
v = Qnil;
}
else if (!RB_TYPE_P(vmax, T_FLOAT) && (v = rb_check_to_integer(vmax, "to_int"), !NIL_P(v))) {
- v = rand_int(&rnd->mt, v, 1);
+ v = rand_int(obj, rnd, v, 1);
}
else if (v = rb_check_to_float(vmax), !NIL_P(v)) {
- double max = float_value(v);
- if (max > 0.0)
- v = rb_float_new(max * genrand_real(&rnd->mt));
- else
+ max = float_value(v);
+ if (max < 0.0) {
v = Qnil;
+ }
+ else {
+ uint32_t a, b;
+ double r;
+
+ float_rand:
+ a = random_int32(obj, rnd);
+ b = random_int32(obj, rnd);
+ r = int_pair_to_real_exclusive(a, b);
+ if (max > 0.0) r *= max;;
+ v = rb_float_new(r);
+ }
}
- else if ((v = rand_range(&rnd->mt, vmax)) != Qfalse) {
+ else if ((v = rand_range(obj, rnd, vmax)) != Qfalse) {
/* nothing to do */
}
else {
@@ -1171,6 +1243,13 @@ rand_random(int argc, VALUE *argv, rb_random_t *rnd)
return v;
}
+static VALUE
+rand_random_number(int argc, VALUE *argv, VALUE obj)
+{
+ if (argc == 1 && argv[0] == INT2FIX(0)) --argc;
+ return rand_random(argc, argv, obj, try_get_rnd(obj));
+}
+
/*
* call-seq:
* prng1 == prng2 -> true or false
@@ -1244,18 +1323,18 @@ static VALUE
rb_f_rand(int argc, VALUE *argv, VALUE obj)
{
VALUE v, vmax, r;
- struct MT *mt = default_mt();
+ rb_random_t *rnd = rand_start(&default_rand);
if (argc == 0) goto zero_arg;
rb_scan_args(argc, argv, "01", &vmax);
if (NIL_P(vmax)) goto zero_arg;
- if ((v = rand_range(mt, vmax)) != Qfalse) {
+ if ((v = rand_range(Qnil, rnd, vmax)) != Qfalse) {
return v;
}
vmax = rb_to_int(vmax);
- if (vmax == INT2FIX(0) || NIL_P(r = rand_int(mt, vmax, 0))) {
+ if (vmax == INT2FIX(0) || NIL_P(r = rand_int(Qnil, rnd, vmax, 0))) {
zero_arg:
- return DBL2NUM(genrand_real(mt));
+ return DBL2NUM(genrand_real(&rnd->mt));
}
return r;
}
@@ -1271,7 +1350,7 @@ rb_f_rand(int argc, VALUE *argv, VALUE obj)
static VALUE
random_s_rand(int argc, VALUE *argv, VALUE obj)
{
- return rand_random(argc, argv, rand_start(&default_rand));
+ return rand_random(argc, argv, Qnil, rand_start(&default_rand));
}
#define SIP_HASH_STREAMING 0
@@ -1430,6 +1509,12 @@ InitVM_Random(void)
rb_define_singleton_method(rb_cRandom, "raw_seed", random_raw_seed, 1);
rb_define_private_method(CLASS_OF(rb_cRandom), "state", random_s_state, 0);
rb_define_private_method(CLASS_OF(rb_cRandom), "left", random_s_left, 0);
+
+ {
+ VALUE m = rb_define_module_under(rb_cRandom, "Formatter");
+ rb_include_module(rb_cRandom, m);
+ rb_define_method(m, "random_number", rand_random_number, -1);
+ }
}
#undef rb_intern