x/ffi: wrap c/ffi

2024-10-23 11:44:34 +08:00
parent 92c267758e
commit 363be18599
15 changed files with 435 additions and 224 deletions
--- a/c/ffi/_demo/cfunc/main.go
+++ b/c/ffi/_demo/cfunc/main.go
@@ -29,29 +29,37 @@ type array struct {
 	k c.Int
 }

+var (
+	typeInt32   = &ffi.Type{4, 4, ffi.Sint32, nil}
+	typePointer = &ffi.Type{unsafe.Sizeof(0), uint16(unsafe.Alignof(0)), ffi.Pointer, nil}
+)
+
 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)
+	var cif ffi.Cif
+	tarray := &ffi.Type{0, 0, ffi.Struct, &[]*ffi.Type{typeInt32, typeInt32, typeInt32, typeInt32, nil}[0]}
+	status := ffi.PrepCif(&cif, ffi.DefaultAbi, 1, typeInt32, &[]*ffi.Type{tarray}[0])
+	if status != ffi.OK {
+		panic(status)
 	}
 	ar := array{1, 2, 3, 4}
 	var ret int32
-	ffi.Call(sig, c.Func(demo1), unsafe.Pointer(&ret), unsafe.Pointer(&ar))
+	ffi.Call(&cif, c.Func(demo1), unsafe.Pointer(&ret), &[]unsafe.Pointer{unsafe.Pointer(&ar)}[0])
 	c.Printf(c.Str("ret: %d\n"), ret)
 }

 func cdemo2() {
-	sig, err := ffi.NewSignature(ffi.TypeInt32, ffi.TypePointer)
-	if err != nil {
-		panic(err)
+	var cif ffi.Cif
+	status := ffi.PrepCif(&cif, ffi.DefaultAbi, 1, typeInt32, &[]*ffi.Type{typePointer}[0])
+	if status != ffi.OK {
+		panic(status)
 	}
 	var ret int32
 	fn := c.Func(demo1)
-	ffi.Call(sig, c.Func(demo2), unsafe.Pointer(&ret), unsafe.Pointer(&fn))
+	ffi.Call(&cif, c.Func(demo2), unsafe.Pointer(&ret), &[]unsafe.Pointer{unsafe.Pointer(&fn)}[0])
 	c.Printf(c.Str("ret: %d\n"), ret)
 }
--- a/c/ffi/_demo/closure/main.go
+++ b/c/ffi/_demo/closure/main.go
@@ -34,6 +34,11 @@ func demo(a array) c.Int {
 	return a.x + a.y + a.z + a.k
 }

+var (
+	typeInt32   = &ffi.Type{4, 4, ffi.Sint32, nil}
+	typePointer = &ffi.Type{unsafe.Sizeof(0), uint16(unsafe.Alignof(0)), ffi.Pointer, nil}
+)
+
 func main() {
 	gofn()
 	c.Printf(c.Str("\n"))
@@ -41,38 +46,48 @@ func main() {
 }

 func gofn() {
-	sig, err := ffi.NewSignature(ffi.TypeInt32, ffi.TypePointer)
-	if err != nil {
-		panic(err)
+	var cif ffi.Cif
+	status := ffi.PrepCif(&cif, ffi.DefaultAbi, 1, typeInt32, &[]*ffi.Type{typePointer}[0])
+	if status != ffi.OK {
+		panic(status)
 	}
-	closure := ffi.NewClosure()
-	defer closure.Free()
-	err = closure.Bind(sig, func(cif *ffi.Signature, ret unsafe.Pointer, args *unsafe.Pointer, userdata unsafe.Pointer) {
+	var fncode unsafe.Pointer
+	closure := ffi.ClosureAlloc(&fncode)
+	defer ffi.ClosureFree(closure)
+	status = ffi.PreClosureLoc(closure, &cif, func(cif *ffi.Cif, ret unsafe.Pointer, args *unsafe.Pointer, userdata unsafe.Pointer) {
 		ar := *(*array)(ffi.Index(args, 0))
 		*(*c.Int)(ret) = demo(ar)
-	}, nil)
+	}, nil, fncode)
+	if status != ffi.OK {
+		panic(status)
+	}
 	var ret int32
-	ffi.Call(sig, c.Func(demo2), unsafe.Pointer(&ret), unsafe.Pointer(&closure.Fn))
+	ffi.Call(&cif, c.Func(demo2), unsafe.Pointer(&ret), &[]unsafe.Pointer{unsafe.Pointer(&fncode)}[0])
 	c.Printf(c.Str("ret: %d\n"), ret)
 }

 func goclosure() {
-	sig, err := ffi.NewSignature(ffi.TypeInt32, ffi.TypePointer)
-	if err != nil {
-		panic(err)
+	var cif ffi.Cif
+	status := ffi.PrepCif(&cif, ffi.DefaultAbi, 1, typeInt32, &[]*ffi.Type{typePointer}[0])
+	if status != ffi.OK {
+		panic(status)
 	}
 	fn := func(ar array) c.Int {
-		c.Printf(c.Str("call closure %d\n"), sig.NArgs)
+		c.Printf(c.Str("call closure %d\n"), cif.NArgs)
 		return demo(ar)
 	}
-	closure := ffi.NewClosure()
-	defer closure.Free()
-	err = closure.Bind(sig, func(cif *ffi.Signature, ret unsafe.Pointer, args *unsafe.Pointer, userdata unsafe.Pointer) {
+	var fncode unsafe.Pointer
+	closure := ffi.ClosureAlloc(&fncode)
+	defer ffi.ClosureFree(closure)
+	status = ffi.PreClosureLoc(closure, &cif, func(cif *ffi.Cif, ret unsafe.Pointer, args *unsafe.Pointer, userdata unsafe.Pointer) {
 		ar := *(*array)(ffi.Index(args, 0))
 		fn := *(*func(array) c.Int)(userdata)
 		*(*c.Int)(ret) = fn(ar)
-	}, unsafe.Pointer(&fn))
+	}, unsafe.Pointer(&fn), fncode)
+	if status != ffi.OK {
+		panic(status)
+	}
 	var ret int32
-	ffi.Call(sig, c.Func(demo2), unsafe.Pointer(&ret), unsafe.Pointer(&closure.Fn))
+	ffi.Call(&cif, c.Func(demo2), unsafe.Pointer(&ret), &[]unsafe.Pointer{unsafe.Pointer(&fncode)}[0])
 	c.Printf(c.Str("ret: %d\n"), ret)
 }
--- a/c/ffi/_demo/printf/main.go
+++ b/c/ffi/_demo/printf/main.go
@@ -7,14 +7,20 @@ import (
 	"github.com/goplus/llgo/c/ffi"
 )

+var (
+	typeInt32   = &ffi.Type{4, 4, ffi.Sint32, nil}
+	typePointer = &ffi.Type{unsafe.Sizeof(0), uint16(unsafe.Alignof(0)), ffi.Pointer, nil}
+)
+
 func main() {
-	sig, err := ffi.NewSignatureVar(ffi.TypeInt32, 1, ffi.TypePointer, ffi.TypeInt32)
-	if err != nil {
-		panic(err)
+	var cif ffi.Cif
+	status := ffi.PrepCifVar(&cif, ffi.DefaultAbi, 1, 2, typeInt32, &[]*ffi.Type{typePointer, typeInt32}[0])
+	if status != ffi.OK {
+		panic(status)
 	}
 	var ret int32
 	text := c.Str("hello world: %d\n")
 	var n int32 = 100
-	ffi.Call(sig, c.Func(c.Printf), unsafe.Pointer(&ret), unsafe.Pointer(&text), unsafe.Pointer(&n))
+	ffi.Call(&cif, c.Func(c.Printf), unsafe.Pointer(&ret), &[]unsafe.Pointer{unsafe.Pointer(&text), unsafe.Pointer(&n)}[0])
 	c.Printf(c.Str("ret: %d\n"), ret)
 }
--- a/c/ffi/ffi/_wrap/libffi.c
+++ b/c/ffi/ffi/_wrap/libffi.c
--- a/c/ffi/abi.go
+++ b/c/ffi/abi.go
@@ -3,5 +3,5 @@
 package ffi

 const (
-	DefaultAbi Abi = 1
+	DefaultAbi = 1
 )
--- a/c/ffi/abi_amd64.go
+++ b/c/ffi/abi_amd64.go
@@ -3,5 +3,5 @@
 package ffi

 const (
-	DefaultAbi Abi = 2
+	DefaultAbi = 2
 )
--- a/c/ffi/ffi.go
+++ b/c/ffi/ffi.go
@@ -1,101 +1,127 @@
 package ffi

 import (
-	"fmt"
 	"unsafe"

 	"github.com/goplus/llgo/c"
-	"github.com/goplus/llgo/c/ffi/ffi"
 )

-type Type = ffi.Type
-
-type Signature = ffi.Cif
-
-type Abi c.Uint
-
-type Error c.Uint
+const (
+	LLGoPackage = "link: $(pkg-config --libs libffi); -lffi"
+	LLGoFiles   = "$(pkg-config --cflags libffi): _wrap/libffi.c"
+)

 const (
-	OK Error = iota
+	Void = iota
+	Int
+	Float
+	Double
+	LongDouble
+	Uint8
+	Sint8
+	Uint16
+	Sint16
+	Uint32
+	Sint32
+	Uint64
+	Sint64
+	Struct
+	Pointer
+	Complex
+)
+
+const (
+	OK = iota
 	BAD_TYPEDEF
 	BAD_ABI
 	BAD_ARGTYPE
 )

-func (s Error) Error() string {
-	switch s {
-	case OK:
-		return "ok"
-	case BAD_TYPEDEF:
-		return "bad type def"
-	case BAD_ABI:
-		return "bad ABI"
-	case BAD_ARGTYPE:
-		return "bad argument type"
-	}
-	return fmt.Sprintf("invalid status: %v", int(s))
+type Type struct {
+	Size      uintptr
+	Alignment uint16
+	Type      uint16
+	Elements  **Type
 }

-func NewSignature(ret *Type, args ...*Type) (*Signature, error) {
-	var cif ffi.Cif
-	var atype **Type
-	if len(args) > 0 {
-		atype = &args[0]
-	}
-	status := ffi.PrepCif(&cif, c.Uint(DefaultAbi), c.Uint(len(args)), ret, atype)
-	if status == 0 {
-		return &cif, nil
-	}
-	return nil, Error(status)
+/*typedef struct {
+  ffi_abi abi;
+  unsigned nargs;
+  ffi_type **arg_types;
+  ffi_type *rtype;
+  unsigned bytes;
+  unsigned flags;
+#ifdef FFI_EXTRA_CIF_FIELDS
+  FFI_EXTRA_CIF_FIELDS;
+#endif
+} ffi_cif;
+*/
+
+type Cif struct {
+	Abi      c.Uint
+	NArgs    c.Uint
+	ArgTypes **Type
+	RType    *Type
+	Bytes    c.Uint
+	Flags    c.Uint
+	//Extra    c.Uint
 }

-func NewSignatureVar(ret *Type, fixed int, args ...*Type) (*Signature, error) {
-	var cif ffi.Cif
-	var atype **Type
-	if len(args) > 0 {
-		atype = &args[0]
-	}
-	status := ffi.PrepCifVar(&cif, c.Uint(DefaultAbi), c.Uint(fixed), c.Uint(len(args)), ret, atype)
-	if status == 0 {
-		return &cif, nil
-	}
-	return nil, Error(status)
-}
+/*
+ffi_status
+ffi_prep_cif(ffi_cif *cif,
+			ffi_abi abi,
+			unsigned int nargs,
+			ffi_type *rtype,
+			ffi_type **atypes);
+*/
+//go:linkname PrepCif C.ffi_prep_cif
+func PrepCif(cif *Cif, abi c.Uint, nargs c.Uint, rtype *Type, atype **Type) c.Uint

-func Call(cif *Signature, fn unsafe.Pointer, ret unsafe.Pointer, args ...unsafe.Pointer) {
-	var avalues *unsafe.Pointer
-	if len(args) > 0 {
-		avalues = &args[0]
-	}
-	ffi.Call(cif, fn, ret, avalues)
-}
+/*
+ffi_status ffi_prep_cif_var(ffi_cif *cif,
+			    ffi_abi abi,
+			    unsigned int nfixedargs,
+			    unsigned int ntotalargs,
+			    ffi_type *rtype,
+			    ffi_type **atypes);
+*/
+//go:linkname PrepCifVar C.ffi_prep_cif_var
+func PrepCifVar(cif *Cif, abi c.Uint, nfixedargs c.Uint, ntotalargs c.Uint, rtype *Type, atype **Type) c.Uint

-type Closure struct {
-	ptr unsafe.Pointer
-	Fn  unsafe.Pointer
-}
+/*
+void ffi_call(ffi_cif *cif,
+			void (*fn)(void),
+			void *rvalue,
+			void **avalue);
+*/
+//go:linkname Call C.ffi_call
+func Call(cif *Cif, fn unsafe.Pointer, rvalue unsafe.Pointer, avalue *unsafe.Pointer)

-func NewClosure() *Closure {
-	c := &Closure{}
-	c.ptr = ffi.ClosureAlloc(&c.Fn)
-	return c
-}
+// void *ffi_closure_alloc (size_t size, void **code);
+//
+//go:linkname ClosureAlloc C.llog_ffi_closure_alloc
+func ClosureAlloc(code *unsafe.Pointer) unsafe.Pointer

-func (c *Closure) Free() {
-	if c != nil && c.ptr != nil {
-		ffi.ClosureFree(c.ptr)
-		c.ptr = nil
-	}
-}
+// void ffi_closure_free (void *);
+//
+//go:linkname ClosureFree C.ffi_closure_free
+func ClosureFree(unsafe.Pointer)

-func (c *Closure) Bind(cif *Signature, fn ffi.ClosureFunc, userdata unsafe.Pointer) error {
-	status := ffi.PreClosureLoc(c.ptr, cif, fn, userdata, c.Fn)
-	if status == 0 {
-		return nil
-	}
-	return Error(status)
-}
+/*
+ffi_status
+ffi_prep_closure_loc (ffi_closure*,
+      ffi_cif *,
+      void (*fun)(ffi_cif*,void*,void**,void*),
+      void *user_data,
+      void *codeloc);
+*/
+
+//llgo:type C
+type ClosureFunc func(cif *Cif, ret unsafe.Pointer, args *unsafe.Pointer, userdata unsafe.Pointer)
+
+//go:linkname PreClosureLoc C.ffi_prep_closure_loc
+func PreClosureLoc(closure unsafe.Pointer, cif *Cif, fn ClosureFunc, userdata unsafe.Pointer, codeloc unsafe.Pointer) c.Uint

 func add(ptr unsafe.Pointer, offset uintptr) unsafe.Pointer {
 	return unsafe.Pointer(uintptr(ptr) + offset)
--- a/c/ffi/ffi/ffi.go
+++ b/c/ffi/ffi/ffi.go
@@ -1,117 +0,0 @@
-package ffi
-
-import (
-	"unsafe"
-
-	"github.com/goplus/llgo/c"
-)
-
-const (
-	LLGoPackage = "link: $(pkg-config --libs libffi); -lffi"
-	LLGoFiles   = "$(pkg-config --cflags libffi): _wrap/libffi.c"
-)
-
-const (
-	Void = iota
-	Int
-	Float
-	Double
-	LongDouble
-	Uint8
-	Sint8
-	Uint16
-	Sint16
-	Uint32
-	Sint32
-	Uint64
-	Sint64
-	Struct
-	Pointer
-	Complex
-)
-
-type Type struct {
-	Size      uintptr
-	Alignment uint16
-	Type      uint16
-	Elements  **Type
-}
-
-/*typedef struct {
-  ffi_abi abi;
-  unsigned nargs;
-  ffi_type **arg_types;
-  ffi_type *rtype;
-  unsigned bytes;
-  unsigned flags;
-#ifdef FFI_EXTRA_CIF_FIELDS
-  FFI_EXTRA_CIF_FIELDS;
-#endif
-} ffi_cif;
-*/
-
-type Cif struct {
-	Abi      c.Uint
-	NArgs    c.Uint
-	ArgTypes **Type
-	RType    *Type
-	Bytes    c.Uint
-	Flags    c.Uint
-	//Extra    c.Uint
-}
-
-/*
-ffi_status
-ffi_prep_cif(ffi_cif *cif,
-			ffi_abi abi,
-			unsigned int nargs,
-			ffi_type *rtype,
-			ffi_type **atypes);
-*/
-//go:linkname PrepCif C.ffi_prep_cif
-func PrepCif(cif *Cif, abi c.Uint, nargs c.Uint, rtype *Type, atype **Type) c.Uint
-
-/*
-ffi_status ffi_prep_cif_var(ffi_cif *cif,
-			    ffi_abi abi,
-			    unsigned int nfixedargs,
-			    unsigned int ntotalargs,
-			    ffi_type *rtype,
-			    ffi_type **atypes);
-*/
-//go:linkname PrepCifVar C.ffi_prep_cif_var
-func PrepCifVar(cif *Cif, abi c.Uint, nfixedargs c.Uint, ntotalargs c.Uint, rtype *Type, atype **Type) c.Uint
-
-/*
-void ffi_call(ffi_cif *cif,
-			void (*fn)(void),
-			void *rvalue,
-			void **avalue);
-*/
-//go:linkname Call C.ffi_call
-func Call(cif *Cif, fn unsafe.Pointer, rvalue unsafe.Pointer, avalue *unsafe.Pointer)
-
-// void *ffi_closure_alloc (size_t size, void **code);
-//
-//go:linkname ClosureAlloc C.llog_ffi_closure_alloc
-func ClosureAlloc(code *unsafe.Pointer) unsafe.Pointer
-
-// void ffi_closure_free (void *);
-//
-//go:linkname ClosureFree C.ffi_closure_free
-func ClosureFree(unsafe.Pointer)
-
-/*
-ffi_status
-ffi_prep_closure_loc (ffi_closure*,
-      ffi_cif *,
-      void (*fun)(ffi_cif*,void*,void**,void*),
-      void *user_data,
-      void *codeloc);
-*/
-
-//llgo:type C
-type ClosureFunc func(cif *Cif, ret unsafe.Pointer, args *unsafe.Pointer, userdata unsafe.Pointer)
-
-//go:linkname PreClosureLoc C.ffi_prep_closure_loc
-func PreClosureLoc(closure unsafe.Pointer, cif *Cif, fn ClosureFunc, userdata unsafe.Pointer, codeloc unsafe.Pointer) c.Uint
--- a/x/ffi/_demo/_wrap/wrap.c
+++ b/x/ffi/_demo/_wrap/wrap.c
@@ -0,0 +1,25 @@
+#include <stdio.h>
+
+struct array
+{
+    int x;
+    int y;
+    int z;
+    int k;
+};
+
+int demo1(struct array a)
+{
+    printf("c.demo1: %d %d %d %d\n",a.x,a.y,a.z,a.k);
+    return a.x+a.y+a.z+a.k;
+}
+
+int demo2( int (*fn)(struct array)) {
+    printf("c.demo2: %p\n",fn);
+    struct array a;
+    a.x = 1;
+    a.y = 2;
+    a.z = 3;
+    a.k = 4;
+    return (*fn)(a);
+}
--- a/x/ffi/_demo/cfunc/main.go
+++ b/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)
+}
--- a/x/ffi/_demo/closure/main.go
+++ b/x/ffi/_demo/closure/main.go
@@ -0,0 +1,78 @@
+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 demo(a array) c.Int {
+	c.Printf(c.Str("go.demo %d %d %d %d\n"), a.x, a.y, a.z, a.k)
+	return a.x + a.y + a.z + a.k
+}
+
+func main() {
+	gofn()
+	c.Printf(c.Str("\n"))
+	goclosure()
+}
+
+func gofn() {
+	sig, err := ffi.NewSignature(ffi.TypeInt32, ffi.TypePointer)
+	if err != nil {
+		panic(err)
+	}
+	closure := ffi.NewClosure()
+	defer closure.Free()
+	err = closure.Bind(sig, func(cif *ffi.Signature, ret unsafe.Pointer, args *unsafe.Pointer, userdata unsafe.Pointer) {
+		ar := *(*array)(ffi.Index(args, 0))
+		*(*c.Int)(ret) = demo(ar)
+	}, nil)
+	var ret int32
+	ffi.Call(sig, c.Func(demo2), unsafe.Pointer(&ret), unsafe.Pointer(&closure.Fn))
+	c.Printf(c.Str("ret: %d\n"), ret)
+}
+
+func goclosure() {
+	sig, err := ffi.NewSignature(ffi.TypeInt32, ffi.TypePointer)
+	if err != nil {
+		panic(err)
+	}
+	fn := func(ar array) c.Int {
+		c.Printf(c.Str("call closure %d\n"), sig.NArgs)
+		return demo(ar)
+	}
+	closure := ffi.NewClosure()
+	defer closure.Free()
+	err = closure.Bind(sig, func(cif *ffi.Signature, ret unsafe.Pointer, args *unsafe.Pointer, userdata unsafe.Pointer) {
+		ar := *(*array)(ffi.Index(args, 0))
+		fn := *(*func(array) c.Int)(userdata)
+		*(*c.Int)(ret) = fn(ar)
+	}, unsafe.Pointer(&fn))
+	var ret int32
+	ffi.Call(sig, c.Func(demo2), unsafe.Pointer(&ret), unsafe.Pointer(&closure.Fn))
+	c.Printf(c.Str("ret: %d\n"), ret)
+}
--- a/x/ffi/_demo/gofunc/main.go
+++ b/x/ffi/_demo/gofunc/main.go
@@ -3,7 +3,7 @@ package main
 import (
 	"unsafe"

-	"github.com/goplus/llgo/c/ffi"
+	"github.com/goplus/llgo/x/ffi"
 )

 type array struct {
--- a/x/ffi/_demo/printf/main.go
+++ b/x/ffi/_demo/printf/main.go
@@ -0,0 +1,20 @@
+package main
+
+import (
+	"unsafe"
+
+	"github.com/goplus/llgo/c"
+	"github.com/goplus/llgo/x/ffi"
+)
+
+func main() {
+	sig, err := ffi.NewSignatureVar(ffi.TypeInt32, 1, ffi.TypePointer, ffi.TypeInt32)
+	if err != nil {
+		panic(err)
+	}
+	var ret int32
+	text := c.Str("hello world: %d\n")
+	var n int32 = 100
+	ffi.Call(sig, c.Func(c.Printf), unsafe.Pointer(&ret), unsafe.Pointer(&text), unsafe.Pointer(&n))
+	c.Printf(c.Str("ret: %d\n"), ret)
+}
--- a/x/ffi/ffi.go
+++ b/x/ffi/ffi.go
@@ -0,0 +1,93 @@
+package ffi
+
+import (
+	"fmt"
+	"unsafe"
+
+	"github.com/goplus/llgo/c"
+	"github.com/goplus/llgo/c/ffi"
+)
+
+type Type = ffi.Type
+
+type Signature = ffi.Cif
+
+type Error int
+
+func (s Error) Error() string {
+	switch s {
+	case ffi.OK:
+		return "ok"
+	case ffi.BAD_TYPEDEF:
+		return "bad type def"
+	case ffi.BAD_ABI:
+		return "bad ABI"
+	case ffi.BAD_ARGTYPE:
+		return "bad argument type"
+	}
+	return fmt.Sprintf("invalid status: %v", int(s))
+}
+
+func NewSignature(ret *Type, args ...*Type) (*Signature, error) {
+	var cif Signature
+	var atype **Type
+	if len(args) > 0 {
+		atype = &args[0]
+	}
+	status := ffi.PrepCif(&cif, ffi.DefaultAbi, c.Uint(len(args)), ret, atype)
+	if status == 0 {
+		return &cif, nil
+	}
+	return nil, Error(status)
+}
+
+func NewSignatureVar(ret *Type, fixed int, args ...*Type) (*Signature, error) {
+	var cif Signature
+	var atype **Type
+	if len(args) > 0 {
+		atype = &args[0]
+	}
+	status := ffi.PrepCifVar(&cif, ffi.DefaultAbi, c.Uint(fixed), c.Uint(len(args)), ret, atype)
+	if status == ffi.OK {
+		return &cif, nil
+	}
+	return nil, Error(status)
+}
+
+func Call(cif *Signature, fn unsafe.Pointer, ret unsafe.Pointer, args ...unsafe.Pointer) {
+	var avalues *unsafe.Pointer
+	if len(args) > 0 {
+		avalues = &args[0]
+	}
+	ffi.Call(cif, fn, ret, avalues)
+}
+
+type Closure struct {
+	ptr unsafe.Pointer
+	Fn  unsafe.Pointer
+}
+
+func NewClosure() *Closure {
+	c := &Closure{}
+	c.ptr = ffi.ClosureAlloc(&c.Fn)
+	return c
+}
+
+func (c *Closure) Free() {
+	if c != nil && c.ptr != nil {
+		ffi.ClosureFree(c.ptr)
+		c.ptr = nil
+	}
+}
+
+func (c *Closure) Bind(cif *Signature, fn ffi.ClosureFunc, userdata unsafe.Pointer) error {
+	status := ffi.PreClosureLoc(c.ptr, cif, fn, userdata, c.Fn)
+	if status == ffi.OK {
+		return nil
+	}
+	return Error(status)
+}
+
+func Index(args *unsafe.Pointer, i uintptr) unsafe.Pointer {
+	return ffi.Index(args, i)
+}
--- a/x/ffi/type.go
+++ b/x/ffi/type.go
@@ -4,7 +4,7 @@ import (
 	"unsafe"

 	"github.com/goplus/llgo/c"
-	"github.com/goplus/llgo/c/ffi/ffi"
+	"github.com/goplus/llgo/c/ffi"
 )

 type BasicKind int