dlfcn libffi
install msys2
pacman -S mingw-w64-x86_64-dlfcn
pacman -S mingw-w64-x86_64-libffi
package main
/*
typedef int (*opera_fn)(int ,int);
int opera(void* fn, int a, int b){
opera_fn f = (opera_fn)(fn);
return f(a, b);
}
*/
import "C"
import (
"fmt"
"github.com/jinzhongmin/goffi/pkg/c"
"github.com/jinzhongmin/goffi/pkg/dlfcn"
"github.com/jinzhongmin/usf"
)
func main() {
//###################
// hello world.
//###################
str := c.CStr("hello %s .\n")
defer usf.Free(str)
world := c.CStr("world")
defer usf.Free(world)
fnPrototype := &c.FuncPrototype{
Name: "printf",
InTypes: []c.Type{c.Pointer, c.Pointer},
OutType: c.Void,
}
fnPrototype.Create(dlfcn.DlsymDefault)
fnPrototype.Call([]interface{}{&str, &world})
//###################
// callback
//###################
//define callback prototype
cbprototype := c.DefineCallbackPrototype(c.AbiDefault, c.I32, []c.Type{c.I32, c.I32})
defer cbprototype.Free()
a := C.int(100)
b := C.int(200)
add_fun := cbprototype.CreateCallback(func(args []*c.Value, ret *c.Value) {
a := args[0].I32()
b := args[1].I32()
ret.SetI32(a + b)
})
add := C.opera(add_fun.CFuncPtr(), a, b)
fmt.Println("a + b = ", add)
add_fun.Free()
//change opera_func to mul
mul_fun := cbprototype.CreateCallback(func(args []*c.Value, ret *c.Value) {
a := args[0].I32()
b := args[1].I32()
ret.SetI32(a * b)
})
mul := C.opera(mul_fun.CFuncPtr(), a, b)
fmt.Println("a * b = ", mul)
mul_fun.Free()
}