mrb_value
mrb_ary_shift(mrb_state *mrb, mrb_value self)
{
struct RArray *a = mrb_ary_ptr(self);
mrb_value val;
if (a->len == 0) return mrb_nil_value();
if (a->flags & MRB_ARY_SHARED) {
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;
int size = a->len;
val = *ptr;
while((int)(--size)) {
*ptr = *(ptr+1);
++ptr;
}
--a->len;
}
return val;
}
MRB_API mrb_value
mrb_ary_shift(mrb_state *mrb, mrb_value self)
{
struct RArray *a = mrb_ary_ptr(self);
mrb_int len = ARY_LEN(a);
mrb_value val;
ary_modify_check(mrb, a);
if (len == 0) return mrb_nil_value();
if (ARY_SHARED_P(a)) {
L_SHIFT:
val = a->as.heap.ptr[0];
a->as.heap.ptr++;
a->as.heap.len--;
return val;
}
if (len > ARY_SHIFT_SHARED_MIN) {
ary_make_shared(mrb, a);
goto L_SHIFT;
}
else {
mrb_value *ptr = ARY_PTR(a);
mrb_int size = len;
val = *ptr;
while (--size) {
*ptr = *(ptr+1);
++ptr;
}
ARY_SET_LEN(a, len-1);
}
return val;
}
static mrb_value
ary_subseq(mrb_state *mrb, struct RArray *a, int beg, 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++;
b->flags |= MRB_ARY_SHARED;
return mrb_obj_value(b);
}
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_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);
}