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/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
* GObject introspection: Virtual Function implementation
*
* Copyright (C) 2005 Matthias Clasen
* Copyright (C) 2008,2009 Red Hat, Inc.
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "config.h"
#include <string.h>
#include <glib.h>
#include <girepository/girepository.h>
#include "gibaseinfo-private.h"
#include "girepository-private.h"
#include "gitypelib-internal.h"
#include "givfuncinfo.h"
/**
* GIVFuncInfo:
*
* `GIVFuncInfo` represents a virtual function.
*
* A virtual function is a callable object that belongs to either a
* [type@GIRepository.ObjectInfo] or a [type@GIRepository.InterfaceInfo].
*
* Since: 2.80
*/
GIVFuncInfo *
gi_base_info_find_vfunc (GIRealInfo *rinfo,
uint32_t offset,
uint16_t n_vfuncs,
const char *name)
{
/* FIXME hash */
Header *header = (Header *)rinfo->typelib->data;
for (uint16_t i = 0; i < n_vfuncs; i++)
{
VFuncBlob *fblob = (VFuncBlob *)&rinfo->typelib->data[offset];
const char *fname = (const char *)&rinfo->typelib->data[fblob->name];
if (strcmp (name, fname) == 0)
return (GIVFuncInfo *) gi_base_info_new (GI_INFO_TYPE_VFUNC, (GIBaseInfo*) rinfo,
rinfo->typelib, offset);
offset += header->vfunc_blob_size;
}
return NULL;
}
/**
* gi_vfunc_info_get_flags:
* @info: a #GIVFuncInfo
*
* Obtain the flags for this virtual function info.
*
* See [flags@GIRepository.VFuncInfoFlags] for more information about possible
* flag values.
*
* Returns: the flags
* Since: 2.80
*/
GIVFuncInfoFlags
gi_vfunc_info_get_flags (GIVFuncInfo *info)
{
GIVFuncInfoFlags flags;
GIRealInfo *rinfo = (GIRealInfo *)info;
VFuncBlob *blob;
g_return_val_if_fail (info != NULL, 0);
g_return_val_if_fail (GI_IS_VFUNC_INFO (info), 0);
blob = (VFuncBlob *)&rinfo->typelib->data[rinfo->offset];
flags = 0;
if (blob->must_chain_up)
flags = flags | GI_VFUNC_MUST_CHAIN_UP;
if (blob->must_be_implemented)
flags = flags | GI_VFUNC_MUST_OVERRIDE;
if (blob->must_not_be_implemented)
flags = flags | GI_VFUNC_MUST_NOT_OVERRIDE;
return flags;
}
/**
* gi_vfunc_info_get_offset:
* @info: a #GIVFuncInfo
*
* Obtain the offset of the function pointer in the class struct.
*
* The value `0xFFFF` indicates that the struct offset is unknown.
*
* Returns: the struct offset or `0xFFFF` if it’s unknown
* Since: 2.80
*/
size_t
gi_vfunc_info_get_offset (GIVFuncInfo *info)
{
GIRealInfo *rinfo = (GIRealInfo *)info;
VFuncBlob *blob;
g_return_val_if_fail (info != NULL, 0);
g_return_val_if_fail (GI_IS_VFUNC_INFO (info), 0);
blob = (VFuncBlob *)&rinfo->typelib->data[rinfo->offset];
return blob->struct_offset;
}
/**
* gi_vfunc_info_get_signal:
* @info: a #GIVFuncInfo
*
* Obtain the signal for the virtual function if one is set.
*
* The signal comes from the object or interface to which
* this virtual function belongs.
*
* Returns: (transfer full) (nullable): the signal, or `NULL` if none is set
* Since: 2.80
*/
GISignalInfo *
gi_vfunc_info_get_signal (GIVFuncInfo *info)
{
GIRealInfo *rinfo = (GIRealInfo *)info;
VFuncBlob *blob;
g_return_val_if_fail (info != NULL, 0);
g_return_val_if_fail (GI_IS_VFUNC_INFO (info), 0);
blob = (VFuncBlob *)&rinfo->typelib->data[rinfo->offset];
if (blob->class_closure)
return gi_interface_info_get_signal ((GIInterfaceInfo *)rinfo->container, blob->signal);
return NULL;
}
/**
* gi_vfunc_info_get_invoker:
* @info: a #GIVFuncInfo
*
* If this virtual function has an associated invoker method, this
* method will return it. An invoker method is a C entry point.
*
* Not all virtuals will have invokers.
*
* Returns: (transfer full) (nullable): The [type@GIRepository.FunctionInfo] or
* `NULL` if none is set. Free it with [method@GIRepository.BaseInfo.unref]
* when done.
* Since: 2.80
*/
GIFunctionInfo *
gi_vfunc_info_get_invoker (GIVFuncInfo *info)
{
GIRealInfo *rinfo = (GIRealInfo *)info;
VFuncBlob *blob;
GIBaseInfo *container;
GIInfoType parent_type;
g_return_val_if_fail (info != NULL, 0);
g_return_val_if_fail (GI_IS_VFUNC_INFO (info), 0);
blob = (VFuncBlob *)&rinfo->typelib->data[rinfo->offset];
/* 1023 = 0x3ff is the maximum of the 10 bits for invoker index */
if (blob->invoker == 1023)
return NULL;
container = rinfo->container;
parent_type = gi_base_info_get_info_type (container);
if (parent_type == GI_INFO_TYPE_OBJECT)
return gi_object_info_get_method ((GIObjectInfo*)container, blob->invoker);
else if (parent_type == GI_INFO_TYPE_INTERFACE)
return gi_interface_info_get_method ((GIInterfaceInfo*)container, blob->invoker);
else
g_assert_not_reached ();
}
/**
* gi_vfunc_info_get_address:
* @info: a #GIVFuncInfo
* @implementor_gtype: [type@GObject.Type] implementing this virtual function
* @error: return location for a [type@GLib.Error], or `NULL`
*
* Looks up where the implementation for @info is inside the type struct of
* @implementor_gtype.
*
* Returns: address to a function
* Since: 2.80
*/
void *
gi_vfunc_info_get_address (GIVFuncInfo *vfunc_info,
GType implementor_gtype,
GError **error)
{
GIBaseInfo *container_info;
GIInterfaceInfo *interface_info;
GIObjectInfo *object_info;
GIStructInfo *struct_info;
GIFieldInfo *field_info = NULL;
int length, i, offset;
void *implementor_class, *implementor_vtable;
void *func = NULL;
g_return_val_if_fail (vfunc_info != NULL, NULL);
g_return_val_if_fail (GI_IS_VFUNC_INFO (vfunc_info), NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
container_info = gi_base_info_get_container ((GIBaseInfo *) vfunc_info);
if (gi_base_info_get_info_type (container_info) == GI_INFO_TYPE_OBJECT)
{
object_info = (GIObjectInfo*) container_info;
interface_info = NULL;
struct_info = gi_object_info_get_class_struct (object_info);
}
else
{
interface_info = (GIInterfaceInfo*) container_info;
object_info = NULL;
struct_info = gi_interface_info_get_iface_struct (interface_info);
}
length = gi_struct_info_get_n_fields (struct_info);
for (i = 0; i < length; i++)
{
field_info = gi_struct_info_get_field (struct_info, i);
if (strcmp (gi_base_info_get_name ( (GIBaseInfo*) field_info),
gi_base_info_get_name ( (GIBaseInfo*) vfunc_info)) != 0) {
gi_base_info_unref ((GIBaseInfo *) field_info);
field_info = NULL;
continue;
}
break;
}
if (field_info == NULL)
{
g_set_error (error,
GI_INVOKE_ERROR,
GI_INVOKE_ERROR_SYMBOL_NOT_FOUND,
"Couldn't find struct field for this vfunc");
goto out;
}
implementor_class = g_type_class_ref (implementor_gtype);
if (object_info)
{
implementor_vtable = implementor_class;
}
else
{
GType interface_type;
interface_type = gi_registered_type_info_get_g_type ((GIRegisteredTypeInfo*) interface_info);
implementor_vtable = g_type_interface_peek (implementor_class, interface_type);
}
offset = gi_field_info_get_offset (field_info);
func = *(void**) G_STRUCT_MEMBER_P (implementor_vtable, offset);
g_type_class_unref (implementor_class);
gi_base_info_unref ((GIBaseInfo *) field_info);
if (func == NULL)
{
g_set_error (error,
GI_INVOKE_ERROR,
GI_INVOKE_ERROR_SYMBOL_NOT_FOUND,
"Class %s doesn't implement %s",
g_type_name (implementor_gtype),
gi_base_info_get_name ( (GIBaseInfo*) vfunc_info));
goto out;
}
out:
gi_base_info_unref ((GIBaseInfo*) struct_info);
return func;
}
/**
* gi_vfunc_info_invoke: (skip)
* @info: a #GIVFuncInfo describing the virtual function to invoke
* @implementor: [type@GObject.Type] of the type that implements this virtual
* function
* @in_args: (array length=n_in_args) (nullable): an array of
* [struct@GIRepository.Argument]s, one for each ‘in’ parameter of @info. If
* there are no ‘in’ parameters, @in_args can be `NULL`
* @n_in_args: the length of the @in_args array
* @out_args: (array length=n_out_args) (nullable): an array of
* [struct@GIRepository.Argument]s allocated by the caller, one for each
* ‘out’ parameter of @info. If there are no ‘out’ parameters, @out_args may
* be `NULL`
* @n_out_args: the length of the @out_args array
* @return_value: (out caller-allocates) (not optional) (nullable): return
* location for the return value from the vfunc; `NULL` may be returned if
* the vfunc returns that
* @error: return location for detailed error information, or `NULL`
*
* Invokes the function described in @info with the given
* arguments.
*
* Note that ‘inout’ parameters must appear in both argument lists.
*
* Returns: `TRUE` if the vfunc was executed successfully and didn’t throw
* a [type@GLib.Error]; `FALSE` if @error is set
* Since: 2.80
*/
gboolean
gi_vfunc_info_invoke (GIVFuncInfo *info,
GType implementor,
const GIArgument *in_args,
size_t n_in_args,
GIArgument *out_args,
size_t n_out_args,
GIArgument *return_value,
GError **error)
{
void *func;
GError *local_error = NULL;
g_return_val_if_fail (info != NULL, FALSE);
g_return_val_if_fail (GI_IS_VFUNC_INFO (info), FALSE);
g_return_val_if_fail (in_args != NULL || n_in_args == 0, FALSE);
g_return_val_if_fail (out_args != NULL || n_out_args == 0, FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
func = gi_vfunc_info_get_address (info, implementor, &local_error);
if (local_error != NULL)
{
g_propagate_error (error, g_steal_pointer (&local_error));
return FALSE;
}
return gi_callable_info_invoke ((GICallableInfo*) info,
func,
in_args,
n_in_args,
out_args,
n_out_args,
return_value,
error);
}
void
gi_vfunc_info_class_init (gpointer g_class,
gpointer class_data)
{
GIBaseInfoClass *info_class = g_class;
info_class->info_type = GI_INFO_TYPE_VFUNC;
}