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 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 mrb_value
ary_subseq(mrb_state *mrb, struct RArray *a, mrb_int beg, mrb_int len)
{
struct RArray *b;
if (!ARY_SHARED_P(a) && len <= ARY_SHIFT_SHARED_MIN) {
return mrb_ary_new_from_values(mrb, len, ARY_PTR(a)+beg);
}
ary_make_shared(mrb, a);
b = (struct RArray*)mrb_obj_alloc(mrb, MRB_TT_ARRAY, mrb->array_class);
b->as.heap.ptr = a->as.heap.ptr + beg;
b->as.heap.len = len;
b->as.heap.aux.shared = a->as.heap.aux.shared;
b->as.heap.aux.shared->refcnt++;
ARY_SET_SHARED_FLAG(b);
return mrb_obj_value(b);
}
static void
ary_make_shared(mrb_state *mrb, struct RArray *a)
{
if (!ARY_SHARED_P(a) && !ARY_EMBED_P(a)) {
mrb_shared_array *shared = (mrb_shared_array *)mrb_malloc(mrb, sizeof(mrb_shared_array));
mrb_value *ptr = a->as.heap.ptr;
mrb_int len = a->as.heap.len;
shared->refcnt = 1;
if (a->as.heap.aux.capa > len) {
a->as.heap.ptr = shared->ptr = (mrb_value *)mrb_realloc(mrb, ptr, sizeof(mrb_value)*len+1);
}
else {
shared->ptr = ptr;
}
shared->len = len;
a->as.heap.aux.shared = shared;
ARY_SET_SHARED_FLAG(a);
}
}
static void
ary_replace(mrb_state *mrb, struct RArray *a, struct RArray *b)
{
mrb_int len = ARY_LEN(b);
ary_modify_check(mrb, a);
if (a == b) return;
if (ARY_SHARED_P(a)) {
mrb_ary_decref(mrb, a->as.heap.aux.shared);
a->as.heap.aux.capa = 0;
a->as.heap.len = 0;
a->as.heap.ptr = NULL;
ARY_UNSET_SHARED_FLAG(a);
}
if (ARY_SHARED_P(b)) {
shared_b:
if (ARY_EMBED_P(a)) {
ARY_UNSET_EMBED_FLAG(a);
}
else {
mrb_free(mrb, a->as.heap.ptr);
}
a->as.heap.ptr = b->as.heap.ptr;
a->as.heap.len = len;
a->as.heap.aux.shared = b->as.heap.aux.shared;
a->as.heap.aux.shared->refcnt++;
ARY_SET_SHARED_FLAG(a);
mrb_write_barrier(mrb, (struct RBasic*)a);
return;
}
if (!MRB_FROZEN_P(b) && len > ARY_REPLACE_SHARED_MIN) {
ary_make_shared(mrb, b);
goto shared_b;
}
if (ARY_CAPA(a) < len)
ary_expand_capa(mrb, a, len);
array_copy(ARY_PTR(a), ARY_PTR(b), len);
mrb_write_barrier(mrb, (struct RBasic*)a);
ARY_SET_LEN(a, len);
}
