cgo: add support for nested structs and unions

cgo/testdata/types.go

@@ -44,7 +44,23 @@ typedef union union2d {
 } union2d_t;
 typedef union {
 	unsigned char arr[10];
-} unionarrary_t;
+} unionarray_t;
+
+// Nested structs and unions.
+typedef struct {
+	point2d_t begin;
+	point2d_t end;
+	int       tag;
+	union {
+		point2d_t area;
+		point3d_t solid;
+	} coord;
+} struct_nested_t;
+typedef union {
+	point3d_t    point;
+	unionarray_t array;
+	union3_t     thing;
+} union_nested_t;
 
 // Enums. These define constant numbers. All these constants must be given the
 // correct number.
@@ -108,7 +124,11 @@ var (
 	_ C.union1_t
 	_ C.union3_t
 	_ C.union2d_t
-	_ C.unionarrary_t
+	_ C.unionarray_t
+
+	// Nested structs and unions.
+	_ C.struct_nested_t
+	_ C.union_nested_t
 
 	// Enums (anonymous and named).
 	_ C.option_t

cgo/testdata/types.out.go

@@ -34,7 +34,7 @@ type C.uint uint32
 type C.ulong uint32
 type C.ulonglong uint64
 type C.ushort uint16
-type C.bitfield_t = C.struct_2
+type C.bitfield_t = C.struct_4
 type C.myIntArray = [10]C.int
 type C.myint = C.int
 type C.option2_t = C.uint
@@ -44,6 +44,13 @@ type C.point2d_t = struct {
 	y C.int
 }
 type C.point3d_t = C.struct_point3d
+type C.struct_nested_t = struct {
+	begin C.point2d_t
+	end   C.point2d_t
+	tag   C.int
+
+	coord C.union_2
+}
 type C.types_t = struct {
 	f   float32
 	d   float64
@@ -52,22 +59,23 @@ type C.types_t = struct {
 type C.union1_t = struct{ i C.int }
 type C.union2d_t = C.union_union2d
 type C.union3_t = C.union_1
-type C.unionarrary_t = struct{ arr [10]C.uchar }
+type C.union_nested_t = C.union_3
+type C.unionarray_t = struct{ arr [10]C.uchar }
 
-func (s *C.struct_2) bitfield_a() C.uchar          { return s.__bitfield_1 & 0x1f }
-func (s *C.struct_2) set_bitfield_a(value C.uchar) { s.__bitfield_1 = s.__bitfield_1&^0x1f | value&0x1f<<0 }
-func (s *C.struct_2) bitfield_b() C.uchar {
+func (s *C.struct_4) bitfield_a() C.uchar          { return s.__bitfield_1 & 0x1f }
+func (s *C.struct_4) set_bitfield_a(value C.uchar) { s.__bitfield_1 = s.__bitfield_1&^0x1f | value&0x1f<<0 }
+func (s *C.struct_4) bitfield_b() C.uchar {
 	return s.__bitfield_1 >> 5 & 0x1
 }
-func (s *C.struct_2) set_bitfield_b(value C.uchar) { s.__bitfield_1 = s.__bitfield_1&^0x20 | value&0x1<<5 }
-func (s *C.struct_2) bitfield_c() C.uchar {
+func (s *C.struct_4) set_bitfield_b(value C.uchar) { s.__bitfield_1 = s.__bitfield_1&^0x20 | value&0x1<<5 }
+func (s *C.struct_4) bitfield_c() C.uchar {
 	return s.__bitfield_1 >> 6
 }
-func (s *C.struct_2) set_bitfield_c(value C.uchar,
+func (s *C.struct_4) set_bitfield_c(value C.uchar,
 
 ) { s.__bitfield_1 = s.__bitfield_1&0x3f | value<<6 }
 
-type C.struct_2 struct {
+type C.struct_4 struct {
 	start        C.uchar
 	__bitfield_1 C.uchar
 
@@ -92,6 +100,17 @@ func (union *C.union_1) unionfield_s() *C.short { return (*C.short)(unsafe.Point
 
 type C.union_1 struct{ $union uint64 }
 
+func (union *C.union_2) unionfield_area() *C.point2d_t  { return (*C.point2d_t)(unsafe.Pointer(&union.$union)) }
+func (union *C.union_2) unionfield_solid() *C.point3d_t { return (*C.point3d_t)(unsafe.Pointer(&union.$union)) }
+
+type C.union_2 struct{ $union [3]uint32 }
+
+func (union *C.union_3) unionfield_point() *C.point3d_t    { return (*C.point3d_t)(unsafe.Pointer(&union.$union)) }
+func (union *C.union_3) unionfield_array() *C.unionarray_t { return (*C.unionarray_t)(unsafe.Pointer(&union.$union)) }
+func (union *C.union_3) unionfield_thing() *C.union3_t     { return (*C.union3_t)(unsafe.Pointer(&union.$union)) }
+
+type C.union_3 struct{ $union [2]uint64 }
+
 func (union *C.union_union2d) unionfield_i() *C.int      { return (*C.int)(unsafe.Pointer(&union.$union)) }
 func (union *C.union_union2d) unionfield_d() *[2]float64 { return (*[2]float64)(unsafe.Pointer(&union.$union)) }