#include <mruby.h>

#include <mruby/array.h>

#include <mruby/class.h>

#include <mruby/string.h>

#include <mruby/range.h>

#include "value_array.h"

#define ARY_DEFAULT_LEN 4

#define ARY_SHRINK_RATIO 5 /* must be larger than 2 */

#define ARY_C_MAX_SIZE (SIZE_MAX / sizeof(mrb_value))

#define ARY_MAX_SIZE ((ARY_C_MAX_SIZE < (size_t)MRB_INT_MAX) ? (mrb_int)ARY_C_MAX_SIZE : MRB_INT_MAX-1)

static struct RArray*

ary_new_capa(mrb_state *mrb, mrb_int capa)

{

struct RArray *a;

size_t blen;

if (capa > ARY_MAX_SIZE) {

mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");

}

blen = capa * sizeof(mrb_value);

a = (struct RArray*)mrb_obj_alloc(mrb, MRB_TT_ARRAY, mrb->array_class);

a->ptr = (mrb_value *)mrb_malloc(mrb, blen);

a->aux.capa = capa;

a->len = 0;

return a;

}

MRB_API mrb_value

mrb_ary_new_capa(mrb_state *mrb, mrb_int capa)

{

struct RArray *a = ary_new_capa(mrb, capa);

return mrb_obj_value(a);

}

MRB_API mrb_value

mrb_ary_new(mrb_state *mrb)

{

return mrb_ary_new_capa(mrb, 0);

}

static inline void

array_copy(mrb_value *dst, const mrb_value *src, mrb_int size)

{

mrb_int i;

for (i = 0; i < size; i++) {

dst[i] = src[i];

}

}

MRB_API mrb_value

mrb_ary_new_from_values(mrb_state *mrb, mrb_int size, const mrb_value *vals)

{

struct RArray *a = ary_new_capa(mrb, size);

array_copy(a->ptr, vals, size);

a->len = size;

return mrb_obj_value(a);

}

MRB_API mrb_value

mrb_assoc_new(mrb_state *mrb, mrb_value car, mrb_value cdr)

{

struct RArray *a;

a = ary_new_capa(mrb, 2);

a->ptr[0] = car;

a->ptr[1] = cdr;

a->len = 2;

return mrb_obj_value(a);

}

static void

ary_fill_with_nil(mrb_value *ptr, mrb_int size)

{

mrb_value nil = mrb_nil_value();

while (size--) {

*ptr++ = nil;

}

}

static void

ary_modify(mrb_state *mrb, struct RArray *a)

{

if (MRB_FROZEN_P(a)) {

mrb_raise(mrb, E_RUNTIME_ERROR, "can't modify frozen array");

}

if (ARY_SHARED_P(a)) {

mrb_shared_array *shared = a->aux.shared;

if (shared->refcnt == 1 && a->ptr == shared->ptr) {

a->ptr = shared->ptr;

a->aux.capa = a->len;

mrb_free(mrb, shared);

}

else {

mrb_value *ptr, *p;

size_t len;

p = a->ptr;

len = a->len * sizeof(mrb_value);

ptr = (mrb_value *)mrb_malloc(mrb, len);

if (p) {

array_copy(ptr, p, a->len);

}

a->ptr = ptr;

a->aux.capa = a->len;

mrb_ary_decref(mrb, shared);

}

ARY_UNSET_SHARED_FLAG(a);

}

}

MRB_API void

mrb_ary_modify(mrb_state *mrb, struct RArray* a)

{

mrb_write_barrier(mrb, (struct RBasic*)a);

ary_modify(mrb, a);

}

static void

ary_make_shared(mrb_state *mrb, struct RArray *a)

{

if (!ARY_SHARED_P(a)) {

mrb_shared_array *shared = (mrb_shared_array *)mrb_malloc(mrb, sizeof(mrb_shared_array));

shared->refcnt = 1;

if (a->aux.capa > a->len) {

a->ptr = shared->ptr = (mrb_value *)mrb_realloc(mrb, a->ptr, sizeof(mrb_value)*a->len+1);

}

else {

shared->ptr = a->ptr;

}

shared->len = a->len;

a->aux.shared = shared;

ARY_SET_SHARED_FLAG(a);

}

}

static void

ary_expand_capa(mrb_state *mrb, struct RArray *a, size_t len)

{

size_t capa = a->aux.capa;

if (len > ARY_MAX_SIZE) {

size_error:

mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");

}

if (capa == 0) {

capa = ARY_DEFAULT_LEN;

}

while (capa < len) {

if (capa <= ARY_MAX_SIZE / 2) {

capa *= 2;

}

else {

capa = len;

}

}

if (capa < len || capa > ARY_MAX_SIZE) {

goto size_error;

}

if (capa > (size_t)a->aux.capa) {

mrb_value *expanded_ptr = (mrb_value *)mrb_realloc(mrb, a->ptr, sizeof(mrb_value)*capa);

a->aux.capa = capa;

a->ptr = expanded_ptr;

}

}

static void

ary_shrink_capa(mrb_state *mrb, struct RArray *a)

{

mrb_int capa = a->aux.capa;

if (capa < ARY_DEFAULT_LEN * 2) return;

if (capa <= a->len * ARY_SHRINK_RATIO) return;

do {

capa /= 2;

if (capa < ARY_DEFAULT_LEN) {

capa = ARY_DEFAULT_LEN;

break;

}

} while (capa > a->len * ARY_SHRINK_RATIO);

if (capa > a->len && capa < a->aux.capa) {

a->aux.capa = capa;

a->ptr = (mrb_value *)mrb_realloc(mrb, a->ptr, sizeof(mrb_value)*capa);

}

}

MRB_API mrb_value

mrb_ary_resize(mrb_state *mrb, mrb_value ary, mrb_int new_len)

{

mrb_int old_len;

struct RArray *a = mrb_ary_ptr(ary);

ary_modify(mrb, a);

old_len = RARRAY_LEN(ary);

if (old_len != new_len) {

a->len = new_len;

if (new_len < old_len) {

ary_shrink_capa(mrb, a);

}

else {

ary_expand_capa(mrb, a, new_len);

ary_fill_with_nil(a->ptr + old_len, new_len - old_len);

}

}

return ary;

}

static mrb_value

mrb_ary_s_create(mrb_state *mrb, mrb_value self)

{

mrb_value *vals;

mrb_int len;

mrb_get_args(mrb, "*", &vals, &len);

return mrb_ary_new_from_values(mrb, len, vals);

}

static void

ary_concat(mrb_state *mrb, struct RArray *a, struct RArray *a2)

{

mrb_int len;

if (a2->len > ARY_MAX_SIZE - a->len) {

mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");

}

len = a->len + a2->len;

ary_modify(mrb, a);

if (a->aux.capa < len) {

ary_expand_capa(mrb, a, len);

}

array_copy(a->ptr+a->len, a2->ptr, a2->len);

mrb_write_barrier(mrb, (struct RBasic*)a);

a->len = len;

}

MRB_API void

mrb_ary_concat(mrb_state *mrb, mrb_value self, mrb_value other)

{

struct RArray *a2 = mrb_ary_ptr(other);

ary_concat(mrb, mrb_ary_ptr(self), a2);

}

static mrb_value

mrb_ary_concat_m(mrb_state *mrb, mrb_value self)

{

mrb_value ary;

mrb_get_args(mrb, "A", &ary);

mrb_ary_concat(mrb, self, ary);

return self;

}

static mrb_value

mrb_ary_plus(mrb_state *mrb, mrb_value self)

{

struct RArray *a1 = mrb_ary_ptr(self);

struct RArray *a2;

mrb_value *ptr;

mrb_int blen;

mrb_get_args(mrb, "a", &ptr, &blen);

if (ARY_MAX_SIZE - blen < a1->len) {

mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");

}

a2 = ary_new_capa(mrb, a1->len + blen);

array_copy(a2->ptr, a1->ptr, a1->len);

array_copy(a2->ptr + a1->len, ptr, blen);

a2->len = a1->len + blen;

return mrb_obj_value(a2);

}

static void

ary_replace(mrb_state *mrb, struct RArray *a, mrb_value *argv, mrb_int len)

{

ary_modify(mrb, a);

if (a->aux.capa < len)

ary_expand_capa(mrb, a, len);

array_copy(a->ptr, argv, len);

mrb_write_barrier(mrb, (struct RBasic*)a);

a->len = len;

}

MRB_API void

mrb_ary_replace(mrb_state *mrb, mrb_value self, mrb_value other)

{

struct RArray *a1 = mrb_ary_ptr(self);

struct RArray *a2 = mrb_ary_ptr(other);

if (a1 != a2) {

ary_replace(mrb, a1, a2->ptr, a2->len);

}

}

static mrb_value

mrb_ary_replace_m(mrb_state *mrb, mrb_value self)

{

mrb_value other;

mrb_get_args(mrb, "A", &other);

mrb_ary_replace(mrb, self, other);

return self;

}

static mrb_value

mrb_ary_times(mrb_state *mrb, mrb_value self)

{

struct RArray *a1 = mrb_ary_ptr(self);

struct RArray *a2;

mrb_value *ptr;

mrb_int times;

mrb_get_args(mrb, "i", &times);

if (times < 0) {

mrb_raise(mrb, E_ARGUMENT_ERROR, "negative argument");

}

if (times == 0) return mrb_ary_new(mrb);

if (ARY_MAX_SIZE / times < a1->len) {

mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");

}

a2 = ary_new_capa(mrb, a1->len * times);

ptr = a2->ptr;

while (times--) {

array_copy(ptr, a1->ptr, a1->len);

ptr += a1->len;

a2->len += a1->len;

}

return mrb_obj_value(a2);

}

static mrb_value

mrb_ary_reverse_bang(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

if (a->len > 1) {

mrb_value *p1, *p2;

ary_modify(mrb, a);

p1 = a->ptr;

p2 = a->ptr + a->len - 1;

while (p1 < p2) {

mrb_value tmp = *p1;

*p1++ = *p2;

*p2-- = tmp;

}

}

return self;

}

static mrb_value

mrb_ary_reverse(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self), *b = ary_new_capa(mrb, a->len);

if (a->len > 0) {

mrb_value *p1, *p2, *e;

p1 = a->ptr;

e = p1 + a->len;

p2 = b->ptr + a->len - 1;

while (p1 < e) {

*p2-- = *p1++;

}

b->len = a->len;

}

return mrb_obj_value(b);

}

MRB_API void

mrb_ary_push(mrb_state *mrb, mrb_value ary, mrb_value elem)

{

struct RArray *a = mrb_ary_ptr(ary);

ary_modify(mrb, a);

if (a->len == a->aux.capa)

ary_expand_capa(mrb, a, a->len + 1);

a->ptr[a->len++] = elem;

mrb_field_write_barrier_value(mrb, (struct RBasic*)a, elem);

}

static mrb_value

mrb_ary_push_m(mrb_state *mrb, mrb_value self)

{

mrb_value *argv;

mrb_int len;

mrb_get_args(mrb, "*", &argv, &len);

while (len--) {

mrb_ary_push(mrb, self, *argv++);

}

return self;

}

MRB_API mrb_value

mrb_ary_pop(mrb_state *mrb, mrb_value ary)

{

struct RArray *a = mrb_ary_ptr(ary);

ary_modify(mrb, a);

if (a->len == 0) return mrb_nil_value();

return a->ptr[--a->len];

}

#define ARY_SHIFT_SHARED_MIN 10

MRB_API mrb_value

mrb_ary_shift(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

mrb_value val;

ary_modify(mrb, a);

if (a->len == 0) return mrb_nil_value();

if (ARY_SHARED_P(a)) {

L_SHIFT:

val = a->ptr[0];

a->ptr++;

a->len--;

return val;

}

if (a->len > ARY_SHIFT_SHARED_MIN) {

ary_make_shared(mrb, a);

goto L_SHIFT;

}

else {

mrb_value *ptr = a->ptr;

mrb_int size = a->len;

val = *ptr;

while (--size) {

*ptr = *(ptr+1);

++ptr;

}

--a->len;

}

return val;

}

MRB_API mrb_value

mrb_ary_unshift(mrb_state *mrb, mrb_value self, mrb_value item)

{

struct RArray *a = mrb_ary_ptr(self);

if (ARY_SHARED_P(a)

&& a->aux.shared->refcnt == 1 /* shared only referenced from this array */

&& a->ptr - a->aux.shared->ptr >= 1) /* there's room for unshifted item */ {

a->ptr--;

a->ptr[0] = item;

}

else {

ary_modify(mrb, a);

if (a->aux.capa < a->len + 1)

ary_expand_capa(mrb, a, a->len + 1);

value_move(a->ptr + 1, a->ptr, a->len);

a->ptr[0] = item;

}

a->len++;

mrb_field_write_barrier_value(mrb, (struct RBasic*)a, item);

return self;

}

static mrb_value

mrb_ary_unshift_m(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

mrb_value *vals;

mrb_int len;

mrb_get_args(mrb, "*", &vals, &len);

if (len > ARY_MAX_SIZE - a->len) {

mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");

}

if (ARY_SHARED_P(a)

&& a->aux.shared->refcnt == 1 /* shared only referenced from this array */

&& a->ptr - a->aux.shared->ptr >= len) /* there's room for unshifted item */ {

a->ptr -= len;

}

else {

ary_modify(mrb, a);

if (len == 0) return self;

if (a->aux.capa < a->len + len)

ary_expand_capa(mrb, a, a->len + len);

value_move(a->ptr + len, a->ptr, a->len);

}

array_copy(a->ptr, vals, len);

a->len += len;

while (len--) {

mrb_field_write_barrier_value(mrb, (struct RBasic*)a, vals[len]);

}

return self;

}

MRB_API mrb_value

mrb_ary_ref(mrb_state *mrb, mrb_value ary, mrb_int n)

{

struct RArray *a = mrb_ary_ptr(ary);

/* range check */

if (n < 0) n += a->len;

if (n < 0 || a->len <= n) return mrb_nil_value();

return a->ptr[n];

}

MRB_API void

mrb_ary_set(mrb_state *mrb, mrb_value ary, mrb_int n, mrb_value val)

{

struct RArray *a = mrb_ary_ptr(ary);

ary_modify(mrb, a);

/* range check */

if (n < 0) {

n += a->len;

if (n < 0) {

mrb_raisef(mrb, E_INDEX_ERROR, "index %S out of array", mrb_fixnum_value(n - a->len));

}

}

if (a->len <= n) {

if (a->aux.capa <= n)

ary_expand_capa(mrb, a, n + 1);

ary_fill_with_nil(a->ptr + a->len, n + 1 - a->len);

a->len = n + 1;

}

a->ptr[n] = val;

mrb_field_write_barrier_value(mrb, (struct RBasic*)a, val);

}

static struct RArray*

ary_dup(mrb_state *mrb, struct RArray *a)

{

struct RArray *d = ary_new_capa(mrb, a->len);

ary_replace(mrb, d, a->ptr, a->len);

return d;

}

MRB_API mrb_value

mrb_ary_splice(mrb_state *mrb, mrb_value ary, mrb_int head, mrb_int len, mrb_value rpl)

{

struct RArray *a = mrb_ary_ptr(ary);

const mrb_value *argv;

mrb_int argc;

size_t tail;

ary_modify(mrb, a);

/* len check */

if (len < 0) mrb_raisef(mrb, E_INDEX_ERROR, "negative length (%S)", mrb_fixnum_value(len));

/* range check */

if (head < 0) {

head += a->len;

if (head < 0) {

mrb_raise(mrb, E_INDEX_ERROR, "index is out of array");

}

}

tail = head + len;

if (a->len < len || (size_t)a->len < tail) {

len = a->len - head;

}

/* size check */

if (mrb_array_p(rpl)) {

argc = RARRAY_LEN(rpl);

argv = RARRAY_PTR(rpl);

if (argv == a->ptr) {

struct RArray *r = ary_dup(mrb, a);

argv = r->ptr;

}

}

else {

argc = 1;

argv = &rpl;

}

if (head >= a->len) {

if (head > ARY_MAX_SIZE - argc) {

mrb_raisef(mrb, E_INDEX_ERROR, "index %S too big", mrb_fixnum_value(head));

}

len = head + argc;

if (len > a->aux.capa) {

ary_expand_capa(mrb, a, head + argc);

}

ary_fill_with_nil(a->ptr + a->len, head - a->len);

if (argc > 0) {

array_copy(a->ptr + head, argv, argc);

}

a->len = len;

}

else {

mrb_int alen;

if (a->len - len > ARY_MAX_SIZE - argc) {

mrb_raisef(mrb, E_INDEX_ERROR, "index %S too big", mrb_fixnum_value(a->len + argc - len));

}

alen = a->len + argc - len;

if (alen > a->aux.capa) {

ary_expand_capa(mrb, a, alen);

}

if (len != argc) {

tail = head + len;

value_move(a->ptr + head + argc, a->ptr + tail, a->len - tail);

a->len = alen;

}

if (argc > 0) {

value_move(a->ptr + head, argv, argc);

}

}

mrb_write_barrier(mrb, (struct RBasic*)a);

return ary;

}

mrb_ary_decref(mrb_state *mrb, mrb_shared_array *shared)

{

shared->refcnt--;

if (shared->refcnt == 0) {

mrb_free(mrb, shared->ptr);

mrb_free(mrb, shared);

}

}

static mrb_value

ary_subseq(mrb_state *mrb, struct RArray *a, mrb_int beg, mrb_int len)

{

struct RArray *b;

ary_make_shared(mrb, a);

b = (struct RArray*)mrb_obj_alloc(mrb, MRB_TT_ARRAY, mrb->array_class);

b->ptr = a->ptr + beg;

b->len = len;

b->aux.shared = a->aux.shared;

b->aux.shared->refcnt++;

ARY_SET_SHARED_FLAG(b);

return mrb_obj_value(b);

}

static mrb_int

aget_index(mrb_state *mrb, mrb_value index)

{

if (mrb_fixnum_p(index)) {

return mrb_fixnum(index);

}

else if (mrb_float_p(index)) {

return (mrb_int)mrb_float(index);

}

else {

mrb_int i, argc;

mrb_value *argv;

mrb_get_args(mrb, "i*", &i, &argv, &argc);

return i;

}

}

static mrb_value

mrb_ary_aget(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

mrb_int i, len;

mrb_value index;

if (mrb_get_args(mrb, "o|i", &index, &len) == 1) {

switch (mrb_type(index)) {

/* a[n..m] */

case MRB_TT_RANGE:

if (mrb_range_beg_len(mrb, index, &i, &len, a->len, TRUE) == 1) {

return ary_subseq(mrb, a, i, len);

}

else {

return mrb_nil_value();

}

case MRB_TT_FIXNUM:

return mrb_ary_ref(mrb, self, mrb_fixnum(index));

default:

return mrb_ary_ref(mrb, self, aget_index(mrb, index));

}

}

i = aget_index(mrb, index);

if (i < 0) i += a->len;

if (i < 0 || a->len < i) return mrb_nil_value();

if (len < 0) return mrb_nil_value();

if (a->len == i) return mrb_ary_new(mrb);

if (len > a->len - i) len = a->len - i;

return ary_subseq(mrb, a, i, len);

}

static mrb_value

mrb_ary_aset(mrb_state *mrb, mrb_value self)

{

mrb_value v1, v2, v3;

mrb_int i, len;

mrb_ary_modify(mrb, mrb_ary_ptr(self));

if (mrb_get_args(mrb, "oo|o", &v1, &v2, &v3) == 2) {

/* a[n..m] = v */

switch (mrb_range_beg_len(mrb, v1, &i, &len, RARRAY_LEN(self), FALSE)) {

case 0: /* not range */

mrb_ary_set(mrb, self, aget_index(mrb, v1), v2);

break;

case 1: /* range */

mrb_ary_splice(mrb, self, i, len, v2);

break;

case 2: /* out of range */

mrb_raisef(mrb, E_RANGE_ERROR, "%S out of range", v1);

break;

}

return v2;

}

/* a[n,m] = v */

mrb_ary_splice(mrb, self, aget_index(mrb, v1), aget_index(mrb, v2), v3);

return v3;

}

static mrb_value

mrb_ary_delete_at(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

mrb_int index;

mrb_value val;

mrb_value *ptr;

mrb_int len;

mrb_get_args(mrb, "i", &index);

if (index < 0) index += a->len;

if (index < 0 || a->len <= index) return mrb_nil_value();

ary_modify(mrb, a);

val = a->ptr[index];

ptr = a->ptr + index;

len = a->len - index;

while (--len) {

*ptr = *(ptr+1);

++ptr;

}

--a->len;

ary_shrink_capa(mrb, a);

return val;

}

static mrb_value

mrb_ary_first(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

mrb_int size;

if (mrb_get_args(mrb, "|i", &size) == 0) {

return (a->len > 0)? a->ptr[0]: mrb_nil_value();

}

if (size < 0) {

mrb_raise(mrb, E_ARGUMENT_ERROR, "negative array size");

}

if (size > a->len) size = a->len;

if (ARY_SHARED_P(a)) {

return ary_subseq(mrb, a, 0, size);

}

return mrb_ary_new_from_values(mrb, size, a->ptr);

}

static mrb_value

mrb_ary_last(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

mrb_int size;

if (mrb_get_args(mrb, "|i", &size) == 0)

return (a->len > 0)? a->ptr[a->len - 1]: mrb_nil_value();

if (size < 0) {

mrb_raise(mrb, E_ARGUMENT_ERROR, "negative array size");

}

if (size > a->len) size = a->len;

if (ARY_SHARED_P(a) || size > ARY_DEFAULT_LEN) {

return ary_subseq(mrb, a, a->len - size, size);

}

return mrb_ary_new_from_values(mrb, size, a->ptr + a->len - size);

}

static mrb_value

mrb_ary_index_m(mrb_state *mrb, mrb_value self)

{

mrb_value obj;

mrb_int i;

mrb_get_args(mrb, "o", &obj);

for (i = 0; i < RARRAY_LEN(self); i++) {

if (mrb_equal(mrb, RARRAY_PTR(self)[i], obj)) {

return mrb_fixnum_value(i);

}

}

return mrb_nil_value();

}

static mrb_value

mrb_ary_rindex_m(mrb_state *mrb, mrb_value self)

{

mrb_value obj;

mrb_int i, len;

mrb_get_args(mrb, "o", &obj);

for (i = RARRAY_LEN(self) - 1; i >= 0; i--) {

if (mrb_equal(mrb, RARRAY_PTR(self)[i], obj)) {

return mrb_fixnum_value(i);

}

if (i > (len = RARRAY_LEN(self))) {

i = len;

}

}

return mrb_nil_value();

}

MRB_API mrb_value

mrb_ary_splat(mrb_state *mrb, mrb_value v)

{

mrb_value a, recv_class;

if (mrb_array_p(v)) {

return v;

}

if (!mrb_respond_to(mrb, v, mrb_intern_lit(mrb, "to_a"))) {

return mrb_ary_new_from_values(mrb, 1, &v);

}

a = mrb_funcall(mrb, v, "to_a", 0);

if (mrb_array_p(a)) {

return a;

}

else if (mrb_nil_p(a)) {

return mrb_ary_new_from_values(mrb, 1, &v);

}

else {

recv_class = mrb_obj_value(mrb_obj_class(mrb, v));

mrb_raisef(mrb, E_TYPE_ERROR, "can't convert %S to Array (%S#to_a gives %S)",

recv_class,

recv_class,

mrb_obj_value(mrb_obj_class(mrb, a))

);

/* not reached */

return mrb_undef_value();

}

}

static mrb_value

mrb_ary_size(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

return mrb_fixnum_value(a->len);

}

MRB_API mrb_value

mrb_ary_clear(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

ary_modify(mrb, a);

if (ARY_SHARED_P(a)) {

mrb_ary_decref(mrb, a->aux.shared);

ARY_UNSET_SHARED_FLAG(a);

}

else {

mrb_free(mrb, a->ptr);

}

a->len = 0;

a->aux.capa = 0;

a->ptr = 0;

return self;

}

static mrb_value

mrb_ary_empty_p(mrb_state *mrb, mrb_value self)

{

struct RArray *a = mrb_ary_ptr(self);

return mrb_bool_value(a->len == 0);

}