How to wrap a C function whose parameters are pointer to structs, so that it can be called from Lua?
- by pierr
I have the follwing C function. How should I wrap it so it can be called from a Lua script?
typedef struct tagT{
int a ;
int b ;
} type_t;
int lib_a_f_4(type_t *t)
{
return t->a * t->b ;
}
I know how to wrapr it if the function parameter type were int or char *. Should I use table type for a C structure?
EDIT: I am using SWIG for the wraping , according to this doc, It seems that I should automatically have this funtion new_type_t(2,3) , but it is not the case.
If you wrap a C structure, it is also
mapped to a Lua userdata. By adding a
metatable to the userdata, this
provides a very natural interface. For
example,
struct Point{ int x,y; };
is used as follows:
p=example.new_Point()
p.x=3
p.y=5
print(p.x,p.y) 3 5
Similar access is provided for unions
and the data members of C++ classes. C
structures are created using a
function new_Point(), but for C++
classes are created using just the
name Point().
