187 lines
5.4 KiB
C
187 lines
5.4 KiB
C
/* go-reflect.c -- implement unsafe.Reflect and unsafe.Typeof for Go.
|
|
|
|
Copyright 2009 The Go Authors. All rights reserved.
|
|
Use of this source code is governed by a BSD-style
|
|
license that can be found in the LICENSE file. */
|
|
|
|
#include <stdlib.h>
|
|
#include <stdint.h>
|
|
|
|
#include "interface.h"
|
|
#include "go-alloc.h"
|
|
#include "go-panic.h"
|
|
#include "go-string.h"
|
|
#include "go-type.h"
|
|
|
|
/* For field alignment. */
|
|
|
|
struct field_align
|
|
{
|
|
char c;
|
|
struct __go_type_descriptor *p;
|
|
};
|
|
|
|
/* The type descriptors in the runtime package. */
|
|
|
|
extern const struct __go_type_descriptor ptr_bool_descriptor
|
|
asm ("__go_td_pN30_libgo_runtime.runtime.BoolType");
|
|
extern const struct __go_type_descriptor ptr_float_descriptor
|
|
asm ("__go_td_pN31_libgo_runtime.runtime.FloatType");
|
|
extern const struct __go_type_descriptor ptr_complex_descriptor
|
|
asm ("__go_td_pN33_libgo_runtime.runtime.ComplexType");
|
|
extern const struct __go_type_descriptor ptr_int_descriptor
|
|
asm ("__go_td_pN29_libgo_runtime.runtime.IntType");
|
|
extern const struct __go_type_descriptor ptr_uint_descriptor
|
|
asm ("__go_td_pN30_libgo_runtime.runtime.UintType");
|
|
extern const struct __go_type_descriptor ptr_string_descriptor
|
|
asm ("__go_td_pN32_libgo_runtime.runtime.StringType");
|
|
extern const struct __go_type_descriptor ptr_unsafe_pointer_decriptor
|
|
asm ("__go_td_pN39_libgo_runtime.runtime.UnsafePointerType");
|
|
extern const struct __go_type_descriptor ptr_array_descriptor
|
|
asm ("__go_td_pN31_libgo_runtime.runtime.ArrayType");
|
|
extern const struct __go_type_descriptor ptr_slice_descriptor
|
|
asm ("__go_td_pN31_libgo_runtime.runtime.SliceType");
|
|
extern const struct __go_type_descriptor ptr_chan_descriptor
|
|
asm ("__go_td_pN30_libgo_runtime.runtime.ChanType");
|
|
extern const struct __go_type_descriptor ptr_func_descriptor
|
|
asm ("__go_td_pN30_libgo_runtime.runtime.FuncType");
|
|
extern const struct __go_type_descriptor ptr_interface_descriptor
|
|
asm ("__go_td_pN35_libgo_runtime.runtime.InterfaceType");
|
|
extern const struct __go_type_descriptor ptr_map_descriptor
|
|
asm ("__go_td_pN29_libgo_runtime.runtime.MapType");
|
|
extern const struct __go_type_descriptor ptr_ptr_descriptor
|
|
asm ("__go_td_pN29_libgo_runtime.runtime.PtrType");
|
|
extern const struct __go_type_descriptor ptr_struct_descriptor
|
|
asm ("__go_td_pN32_libgo_runtime.runtime.StructType");
|
|
|
|
const struct __go_type_descriptor *
|
|
get_descriptor (int code)
|
|
{
|
|
switch (code)
|
|
{
|
|
case GO_BOOL:
|
|
return &ptr_bool_descriptor;
|
|
case GO_FLOAT32:
|
|
case GO_FLOAT64:
|
|
return &ptr_float_descriptor;
|
|
case GO_COMPLEX64:
|
|
case GO_COMPLEX128:
|
|
return &ptr_complex_descriptor;
|
|
case GO_INT16:
|
|
case GO_INT32:
|
|
case GO_INT64:
|
|
case GO_INT8:
|
|
case GO_INT:
|
|
return &ptr_int_descriptor;
|
|
case GO_UINT16:
|
|
case GO_UINT32:
|
|
case GO_UINT64:
|
|
case GO_UINT8:
|
|
case GO_UINTPTR:
|
|
case GO_UINT:
|
|
return &ptr_uint_descriptor;
|
|
case GO_STRING:
|
|
return &ptr_string_descriptor;
|
|
case GO_UNSAFE_POINTER:
|
|
return &ptr_unsafe_pointer_decriptor;
|
|
case GO_ARRAY:
|
|
return &ptr_array_descriptor;
|
|
case GO_SLICE:
|
|
return &ptr_slice_descriptor;
|
|
case GO_CHAN:
|
|
return &ptr_chan_descriptor;
|
|
case GO_FUNC:
|
|
return &ptr_func_descriptor;
|
|
case GO_INTERFACE:
|
|
return &ptr_interface_descriptor;
|
|
case GO_MAP:
|
|
return &ptr_map_descriptor;
|
|
case GO_PTR:
|
|
return &ptr_ptr_descriptor;
|
|
case GO_STRUCT:
|
|
return &ptr_struct_descriptor;
|
|
default:
|
|
abort ();
|
|
}
|
|
}
|
|
|
|
/* Implement unsafe.Reflect. */
|
|
|
|
struct reflect_ret
|
|
{
|
|
struct __go_empty_interface rettype;
|
|
void *addr;
|
|
};
|
|
|
|
struct reflect_ret Reflect (struct __go_empty_interface)
|
|
asm ("libgo_unsafe.unsafe.Reflect");
|
|
|
|
struct reflect_ret
|
|
Reflect (struct __go_empty_interface e)
|
|
{
|
|
struct reflect_ret ret;
|
|
|
|
if (e.__type_descriptor == NULL)
|
|
{
|
|
ret.rettype.__type_descriptor = NULL;
|
|
ret.rettype.__object = NULL;
|
|
ret.addr = NULL;
|
|
}
|
|
else
|
|
{
|
|
size_t size;
|
|
|
|
ret.rettype.__type_descriptor =
|
|
get_descriptor (e.__type_descriptor->__code);
|
|
|
|
/* This memcpy is really just an assignment of a const pointer
|
|
to a non-const pointer. FIXME: We should canonicalize this
|
|
pointer, so that for a given type we always return the same
|
|
pointer. */
|
|
__builtin_memcpy (&ret.rettype.__object, &e.__type_descriptor,
|
|
sizeof (void *));
|
|
|
|
/* Make a copy of the value. */
|
|
size = e.__type_descriptor->__size;
|
|
if (size <= sizeof (uint64_t))
|
|
ret.addr = __go_alloc (sizeof (uint64_t));
|
|
else
|
|
ret.addr = __go_alloc (size);
|
|
if (__go_is_pointer_type (e.__type_descriptor))
|
|
*(void **) ret.addr = e.__object;
|
|
else
|
|
__builtin_memcpy (ret.addr, e.__object, size);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Implement unsafe.Typeof. */
|
|
|
|
struct __go_empty_interface Typeof (struct __go_empty_interface)
|
|
asm ("libgo_unsafe.unsafe.Typeof");
|
|
|
|
struct __go_empty_interface
|
|
Typeof (const struct __go_empty_interface e)
|
|
{
|
|
struct __go_empty_interface ret;
|
|
|
|
if (e.__type_descriptor == NULL)
|
|
{
|
|
ret.__type_descriptor = NULL;
|
|
ret.__object = NULL;
|
|
}
|
|
else
|
|
{
|
|
ret.__type_descriptor = get_descriptor (e.__type_descriptor->__code);
|
|
|
|
/* This memcpy is really just an assignment of a const pointer
|
|
to a non-const pointer. FIXME: We should canonicalize this
|
|
pointer, so that for a given type we always return the same
|
|
pointer. */
|
|
__builtin_memcpy (&ret.__object, &e.__type_descriptor, sizeof (void *));
|
|
}
|
|
|
|
return ret;
|
|
}
|