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#include <mruby.h>
#include <mruby/data.h>
#include <mruby/class.h>
#include <mruby/compile.h>
#include <stdio.h>
// a regular C struct
typedef struct Color
{
char r;
char g;
char b;
} Color;
// we will later be building an interface for it
// A struct that informs the Ruby VM what function to call
// when garbage collecting our struct wrapper. Here nothing
// special needs to be done so the default "mrb_free" function
// is used.
// Ending the struct name with 'mrb_struct' is a
// convention I like to use for these mruby 'internal'
// structs
static const struct mrb_data_type Color_mrb_struct = {
"Color", // name of the class in ruby
mrb_free // the function we want it to call when garbage collected
// ^ you can customize this, but remember to always call mrb_free
// ^ within whatever customization you make
};
static mrb_value
Color_initialize(mrb_state* mrb, mrb_value self) {
//Rectangle *wrapped_value = (Rectangle *) mrb_malloc(mrb, sizeof(Rectangle));
//MyCustomStruct *wrapped_value = (MyCustomStruct *)mrb_malloc(mrb, sizeof(MyCustomStruct));
Color *wrapped_value = (Color *)DATA_PTR(self);
if(wrapped_value) { mrb_free(mrb, wrapped_value); }
mrb_data_init(self, NULL, &Color_mrb_struct);
wrapped_value = (Color *)mrb_malloc(mrb, sizeof(Color));
mrb_int parameter_r; // the value that will be recieved from the function call parameter
mrb_int parameter_g; // the value that will be recieved from the function call parameter
mrb_int parameter_b; // the value that will be recieved from the function call parameter
mrb_get_args(mrb, "iii", ¶meter_r, ¶meter_g, ¶meter_b); // getting the value of the param and storing it.
wrapped_value->r = (char)parameter_r;
wrapped_value->g = (char)parameter_g;
wrapped_value->b = (char)parameter_b;
//mrb_data_init(self, wrapped_value, &mrb_Rectangle_struct);
mrb_data_init(self, wrapped_value, &Color_mrb_struct);
return self;
}
// defining the function to be later bound to a ruby method
static mrb_value
Color_r_getter(mrb_state *mrb, mrb_value self)
{
// Unwrap the Ruby object into a C pointer
struct Color *my_struct = DATA_GET_PTR(
mrb, // The Ruby VM
self, // The Ruby object holding the struct
&Color_mrb_struct, // Address to the custom struct tag we declared above
Color // The struct tag we declared at the top
);
// Get the x value from the struct and convert it into a Ruby object. Return it
return mrb_fixnum_value(my_struct->r);
}
static mrb_value
Color_r_setter(mrb_state* mrb, mrb_value self) {
mrb_int parameter_r; // the value that will be recieved from the function call parameter
mrb_get_args(mrb, "i", ¶meter_r); // getting the value of the param and storing it.
// Unwrap the Ruby object into a C pointer
// same as the function defined above does
Color *my_struct = DATA_GET_PTR(mrb, self, &Color_mrb_struct, Color);
// Set the value in the struct to the new one
// note: we do not need to rerwap the struct or anything as we
// are using a pointer to change the values inside the wrapped
// struct.
my_struct->r = (char)parameter_r;
// Ruby convention is to return the value we set so we do that
return mrb_fixnum_value((char)parameter_r);
}
// gem initializer
void
mrb_basic_struct_example_gem_init(mrb_state* mrb) {
struct RClass *basic_struct_example_class = mrb_define_module(mrb, "BasicStructExample");
struct RClass *color_class = mrb_define_class_under(
mrb,
basic_struct_example_class,
"Color",
mrb->object_class
);
// This macro MUST be called and it must be after the class is defined
MRB_SET_INSTANCE_TT(color_class, MRB_TT_DATA);
mrb_define_method(
mrb, // Mruby VM state
color_class, // Class we bind method to
"initialize", // Name of method
Color_initialize, // Function we are binding as a method
MRB_ARGS_ANY() // How many arguments are optional/required
);
mrb_define_method(
mrb, // Mruby VM state
color_class, // Class we bind method to
"r", // Name of method
Color_r_getter, // Function we are binding as a method
MRB_ARGS_NONE() // How many arguments are optional/required
);
mrb_define_method(
mrb, // Mruby VM state
color_class, // Class we bind method to
"r=", // Name of method
Color_r_setter, // Function we are binding as a method
MRB_ARGS_ANY() // How many arguments are optional/required
);
}
// gem finalizer
void
mrb_basic_struct_example_gem_final(mrb_state* mrb) {
}
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