In this post we’re going to look at a simple example of how to create a static C library and use it from C3.
C library #
Create mylib.c
typedef struct Point Point;
struct Point {
int x;
int y;
};
void point_add(Point* a, Point* b, Point* c)
{
c->x = a->x + b->x;
c->y = a->y + b->y;
}
Now, let’s create our static library.
gcc -c mylib.c
ar rcs libmylib.a mylib.o
Calling from C3 #
Create main.c3
import std;
struct Point
{
int x;
int y;
}
extern fn void point_add(Point* a, Point* b, Point* dest);
fn int main()
{
Point a = { 1, 1 };
Point b = { 1, 2 };
Point c = {};
point_add(&a, &b, &c);
io::printfn("x: %d, y: %d", c.x, c.y);
return 0;
}
All we had to do was define the appropriate struct and a function declaration with
the extern keyword.
Now, compile the C3 source file and link our C library.
c3c compile main.c3 -L . -l mylib
./main
x: 2, y: 3
It would be nice to put this in a module with a wrapper so that we could
call point::add instead. I’ll cover this in a later post.