x/ffi: wrap c/ffi

x/ffi/_demo/cfunc/main.go

@@ -0,0 +1,57 @@
+package main
+
+import (
+	"unsafe"
+
+	"github.com/goplus/llgo/c"
+	"github.com/goplus/llgo/x/ffi"
+)
+
+const (
+	LLGoPackage = "link"
+	LLGoFiles   = "../_wrap/wrap.c"
+)
+
+//llgo:type C
+type Callback func(array) c.Int
+
+//go:linkname demo1 C.demo1
+func demo1(array) c.Int
+
+//go:linkname demo2 C.demo2
+func demo2(fn Callback) c.Int
+
+//llgo:type C
+type array struct {
+	x c.Int
+	y c.Int
+	z c.Int
+	k c.Int
+}
+
+func main() {
+	cdemo1()
+	cdemo2()
+}
+
+func cdemo1() {
+	sig, err := ffi.NewSignature(ffi.TypeInt32, ffi.StructOf(ffi.TypeInt32, ffi.TypeInt32, ffi.TypeInt32, ffi.TypeInt32))
+	if err != nil {
+		panic(err)
+	}
+	ar := array{1, 2, 3, 4}
+	var ret int32
+	ffi.Call(sig, c.Func(demo1), unsafe.Pointer(&ret), unsafe.Pointer(&ar))
+	c.Printf(c.Str("ret: %d\n"), ret)
+}
+
+func cdemo2() {
+	sig, err := ffi.NewSignature(ffi.TypeInt32, ffi.TypePointer)
+	if err != nil {
+		panic(err)
+	}
+	var ret int32
+	fn := c.Func(demo1)
+	ffi.Call(sig, c.Func(demo2), unsafe.Pointer(&ret), unsafe.Pointer(&fn))
+	c.Printf(c.Str("ret: %d\n"), ret)
+}