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#include <fiddle.h>
VALUE rb_cPinned;
VALUE rb_eFiddleClearedReferenceError;
struct pinned_data {
VALUE ptr;
};
static void
pinned_mark(void *ptr)
{
struct pinned_data *data = (struct pinned_data*)ptr;
/* Ensure reference is pinned */
if (data->ptr) {
rb_gc_mark(data->ptr);
}
}
static size_t
pinned_memsize(const void *ptr)
{
return sizeof(struct pinned_data);
}
static const rb_data_type_t pinned_data_type = {
"fiddle/pinned",
{pinned_mark, xfree, pinned_memsize, },
0, 0, RUBY_TYPED_FREE_IMMEDIATELY | RUBY_TYPED_WB_PROTECTED
};
static VALUE
allocate(VALUE klass)
{
struct pinned_data *data;
VALUE obj = TypedData_Make_Struct(klass, struct pinned_data, &pinned_data_type, data);
data->ptr = 0;
return obj;
}
/*
* call-seq:
* Fiddle::Pinned.new(object) => pinned_object
*
* Create a new pinned object reference. The Fiddle::Pinned instance will
* prevent the GC from moving +object+.
*/
static VALUE
initialize(VALUE self, VALUE ref)
{
struct pinned_data *data;
TypedData_Get_Struct(self, struct pinned_data, &pinned_data_type, data);
RB_OBJ_WRITE(self, &data->ptr, ref);
return self;
}
/*
* call-seq: ref
*
* Return the object that this pinned instance references.
*/
static VALUE
ref(VALUE self)
{
struct pinned_data *data;
TypedData_Get_Struct(self, struct pinned_data, &pinned_data_type, data);
if (data->ptr) {
return data->ptr;
} else {
rb_raise(rb_eFiddleClearedReferenceError, "`ref` called on a cleared object");
}
}
/*
* call-seq: clear
*
* Clear the reference to the object this is pinning.
*/
static VALUE
clear(VALUE self)
{
struct pinned_data *data;
TypedData_Get_Struct(self, struct pinned_data, &pinned_data_type, data);
data->ptr = 0;
return self;
}
/*
* call-seq: cleared?
*
* Returns true if the reference has been cleared, otherwise returns false.
*/
static VALUE
cleared_p(VALUE self)
{
struct pinned_data *data;
TypedData_Get_Struct(self, struct pinned_data, &pinned_data_type, data);
if (data->ptr) {
return Qfalse;
} else {
return Qtrue;
}
}
extern VALUE rb_eFiddleError;
void
Init_fiddle_pinned(void)
{
rb_cPinned = rb_define_class_under(mFiddle, "Pinned", rb_cObject);
rb_define_alloc_func(rb_cPinned, allocate);
rb_define_method(rb_cPinned, "initialize", initialize, 1);
rb_define_method(rb_cPinned, "ref", ref, 0);
rb_define_method(rb_cPinned, "clear", clear, 0);
rb_define_method(rb_cPinned, "cleared?", cleared_p, 0);
/*
* Document-class: Fiddle::ClearedReferenceError
*
* Cleared reference exception
*/
rb_eFiddleClearedReferenceError = rb_define_class_under(mFiddle, "ClearedReferenceError", rb_eFiddleError);
}
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