girepository/girffi.c - platform/external/bluetooth/glib.git - Git at Google

 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
  * GObject introspection: Helper functions for ffi integration
  *
  * Copyright (C) 2008 Red Hat, Inc
  * Copyright (C) 2005 Matthias Clasen
  *
  * 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 <sys/types.h>

 #include <errno.h>
 #include <string.h>
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
 #include "girffi.h"
 #include "gibaseinfo-private.h"
 #include "girepository.h"
 #include "girepository-private.h"

 static ffi_type *
 gi_type_tag_get_ffi_type_internal (GITypeTag   tag,
                                    gboolean    is_pointer,
                                    gboolean    is_enum)
 {
   switch (tag)
     {
     case GI_TYPE_TAG_BOOLEAN:
       return &ffi_type_uint;
     case GI_TYPE_TAG_INT8:
       return &ffi_type_sint8;
     case GI_TYPE_TAG_UINT8:
       return &ffi_type_uint8;
     case GI_TYPE_TAG_INT16:
       return &ffi_type_sint16;
     case GI_TYPE_TAG_UINT16:
       return &ffi_type_uint16;
     case GI_TYPE_TAG_INT32:
       return &ffi_type_sint32;
     case GI_TYPE_TAG_UINT32:
     case GI_TYPE_TAG_UNICHAR:
       return &ffi_type_uint32;
     case GI_TYPE_TAG_INT64:
       return &ffi_type_sint64;
     case GI_TYPE_TAG_UINT64:
       return &ffi_type_uint64;
     case GI_TYPE_TAG_GTYPE:
 #if GLIB_SIZEOF_SIZE_T == 4
       return &ffi_type_uint32;
 #elif GLIB_SIZEOF_SIZE_T == 8
       return &ffi_type_uint64;
 #else
 #  error "Unexpected size for size_t: not 4 or 8"
 #endif
     case GI_TYPE_TAG_FLOAT:
       return &ffi_type_float;
     case GI_TYPE_TAG_DOUBLE:
       return &ffi_type_double;
     case GI_TYPE_TAG_UTF8:
     case GI_TYPE_TAG_FILENAME:
     case GI_TYPE_TAG_ARRAY:
     case GI_TYPE_TAG_GLIST:
     case GI_TYPE_TAG_GSLIST:
     case GI_TYPE_TAG_GHASH:
     case GI_TYPE_TAG_ERROR:
       return &ffi_type_pointer;
     case GI_TYPE_TAG_INTERFACE:
       {
         /* We need to handle enums specially:
          * https://bugzilla.gnome.org/show_bug.cgi?id=665150
          */
         if (!is_enum)
           return &ffi_type_pointer;
         else
           return &ffi_type_sint32;
       }
     case GI_TYPE_TAG_VOID:
       if (is_pointer)
         return &ffi_type_pointer;
       else
         return &ffi_type_void;
     default:
       break;
     }

   g_assert_not_reached ();

   return NULL;
 }

 /**
  * gi_type_tag_get_ffi_type:
  * @type_tag: a #GITypeTag
  * @is_pointer: whether this is a pointer type
  *
  * Get the `ffi_type` corresponding to @type_tag.
  *
  * Returns: (transfer none): an `ffi_type` corresponding to the platform default
  *   C ABI for @tag and @is_pointer.
  * Since: 2.80
  */
 ffi_type *
 gi_type_tag_get_ffi_type (GITypeTag   type_tag,
                           gboolean    is_pointer)
 {
   return gi_type_tag_get_ffi_type_internal (type_tag, is_pointer, FALSE);
 }

 /**
  * gi_type_info_get_ffi_type:
  * @info: a #GITypeInfo
  *
  * Get the `ffi_type` corresponding to @info.
  *
  * Returns: (transfer none): a `ffi_type` corresponding to the platform default
  *   C ABI for @info.
  * Since: 2.80
  */
 ffi_type *
 gi_type_info_get_ffi_type (GITypeInfo *info)
 {
   gboolean is_enum = FALSE;
   GIBaseInfo *iinfo;

   if (gi_type_info_get_tag (info) == GI_TYPE_TAG_INTERFACE)
     {
       iinfo = gi_type_info_get_interface (info);
       switch (gi_base_info_get_info_type (iinfo))
         {
         case GI_INFO_TYPE_ENUM:
         case GI_INFO_TYPE_FLAGS:
           is_enum = TRUE;
           break;
         default:
           break;
         }
       gi_base_info_unref (iinfo);
     }

   return gi_type_tag_get_ffi_type_internal (gi_type_info_get_tag (info), gi_type_info_is_pointer (info), is_enum);
 }

 /**
  * gi_callable_info_get_ffi_arg_types:
  * @callable_info: a callable info from a typelib
  * @n_args_p: (out) (optional): the number of arguments returned
  *
  * Get the `ffi_type`s for the arguments of @callable_info.
  *
  * Returns: (transfer container) (array length=n_args_p): an array of
  *   `ffi_type*`. The array itself should be freed using [func@GLib.free] after
  *   use.
  * Since: 2.80
  */
 static ffi_type **
 gi_callable_info_get_ffi_arg_types (GICallableInfo *callable_info,
                                     size_t         *n_args_p)
 {
     ffi_type **arg_types;
     gboolean is_method, throws;
     size_t n_args, n_invoke_args, i, offset;

     g_return_val_if_fail (callable_info != NULL, NULL);

     n_args = gi_callable_info_get_n_args (callable_info);
     is_method = gi_callable_info_is_method (callable_info);
     throws = gi_callable_info_can_throw_gerror (callable_info);
     offset = is_method ? 1 : 0;

     n_invoke_args = n_args;

     if (is_method)
       n_invoke_args++;
     if (throws)
       n_invoke_args++;

     if (n_args_p)
       *n_args_p = n_invoke_args;

     arg_types = (ffi_type **) g_new0 (ffi_type *, n_invoke_args + 1);

     if (is_method)
       arg_types[0] = &ffi_type_pointer;
     if (throws)
       arg_types[n_invoke_args - 1] = &ffi_type_pointer;

     for (i = 0; i < n_args; ++i)
       {
         GIArgInfo arg_info;
         GITypeInfo arg_type;

         gi_callable_info_load_arg (callable_info, i, &arg_info);
         gi_arg_info_load_type_info (&arg_info, &arg_type);
         switch (gi_arg_info_get_direction (&arg_info))
           {
             case GI_DIRECTION_IN:
               arg_types[i + offset] = gi_type_info_get_ffi_type (&arg_type);
               break;
             case GI_DIRECTION_OUT:
             case GI_DIRECTION_INOUT:
               arg_types[i + offset] = &ffi_type_pointer;
               break;
             default:
               g_assert_not_reached ();
           }

         gi_base_info_clear (&arg_type);
         gi_base_info_clear (&arg_info);
       }

     arg_types[n_invoke_args] = NULL;

     return arg_types;
 }

 /**
  * gi_callable_info_get_ffi_return_type:
  * @callable_info: a callable info from a typelib
  *
  * Fetches the `ffi_type` for a corresponding return value of
  * a [class@GIRepository.CallableInfo].
  *
  * Returns: (transfer none): the `ffi_type` for the return value
  * Since: 2.80
  */
 static ffi_type *
 gi_callable_info_get_ffi_return_type (GICallableInfo *callable_info)
 {
   GITypeInfo *return_type;
   ffi_type *return_ffi_type;

   g_return_val_if_fail (callable_info != NULL, NULL);

   return_type = gi_callable_info_get_return_type (callable_info);
   return_ffi_type = gi_type_info_get_ffi_type (return_type);
   gi_base_info_unref((GIBaseInfo*)return_type);

   return return_ffi_type;
 }

 /**
  * gi_function_info_prep_invoker:
  * @info: A #GIFunctionInfo
  * @invoker: (out caller-allocates): Output invoker structure
  * @error: A #GError
  *
  * Initialize the caller-allocated @invoker structure with a cache
  * of information needed to invoke the C function corresponding to
  * @info with the platform’s default ABI.
  *
  * A primary intent of this function is that a dynamic structure allocated
  * by a language binding could contain a [type@GIRepository.FunctionInvoker]
  * structure inside the binding’s function mapping.
  *
  * @invoker must be freed using [method@GIRepository.FunctionInvoker.clear]
  * when it’s finished with.
  *
  * Returns: `TRUE` on success, `FALSE` otherwise with @error set.
  * Since: 2.80
  */
 gboolean
 gi_function_info_prep_invoker (GIFunctionInfo     *info,
                                GIFunctionInvoker  *invoker,
                                GError            **error)
 {
   const char *symbol;
   void *addr;

   g_return_val_if_fail (info != NULL, FALSE);
   g_return_val_if_fail (invoker != NULL, FALSE);

   symbol = gi_function_info_get_symbol ((GIFunctionInfo*) info);

   if (!gi_typelib_symbol (gi_base_info_get_typelib ((GIBaseInfo *) info),
                           symbol, &addr))
     {
       g_set_error (error,
                    GI_INVOKE_ERROR,
                    GI_INVOKE_ERROR_SYMBOL_NOT_FOUND,
                    "Could not locate %s: %s", symbol, g_module_error ());

       return FALSE;
     }

   return gi_function_invoker_new_for_address (addr, (GICallableInfo *) info, invoker, error);
 }

 /**
  * gi_function_invoker_new_for_address:
  * @addr: The address
  * @info: A #GICallableInfo
  * @invoker: (out caller-allocates): Output invoker structure
  * @error: A #GError
  *
  * Initialize the caller-allocated @invoker structure with a cache
  * of information needed to invoke the C function corresponding to
  * @info with the platform’s default ABI.
  *
  * A primary intent of this function is that a dynamic structure allocated
  * by a language binding could contain a [type@GIRepository.FunctionInvoker]
  * structure inside the binding’s function mapping.
  *
  * Returns: `TRUE` on success, `FALSE` otherwise with @error set.
  * Since: 2.80
  */
 gboolean
 gi_function_invoker_new_for_address (void               *addr,
                                      GICallableInfo     *info,
                                      GIFunctionInvoker  *invoker,
                                      GError            **error)
 {
   ffi_type **atypes;
   size_t n_args;

   g_return_val_if_fail (info != NULL, FALSE);
   g_return_val_if_fail (invoker != NULL, FALSE);

   invoker->native_address = addr;

   atypes = gi_callable_info_get_ffi_arg_types (info, &n_args);

   return ffi_prep_cif (&(invoker->cif), FFI_DEFAULT_ABI, n_args,
                        gi_callable_info_get_ffi_return_type (info),
                        atypes) == FFI_OK;
 }

 /**
  * gi_function_invoker_clear:
  * @invoker: (transfer none): A #GIFunctionInvoker
  *
  * Release all resources allocated for the internals of @invoker.
  *
  * Callers are responsible for freeing any resources allocated for the structure
  * itself however.
  *
  * Since: 2.80
  */
 void
 gi_function_invoker_clear (GIFunctionInvoker *invoker)
 {
   g_free (invoker->cif.arg_types);
 }

 typedef struct {
   ffi_closure ffi_closure;
   void *writable_self;
   void *native_address;
 } GIClosureWrapper;

 /**
  * gi_callable_info_create_closure:
  * @callable_info: a callable info from a typelib
  * @cif: a `ffi_cif` structure
  * @callback: the ffi callback
  * @user_data: data to be passed into the callback
  *
  * Prepares a callback for ffi invocation.
  *
  * Returns: (transfer full) (nullable): the `ffi_closure`, or `NULL` on error.
  *   The return value should be freed by calling
  *   [method@GIRepository.CallableInfo.destroy_closure].
  * Since: 2.80
  */
 ffi_closure *
 gi_callable_info_create_closure (GICallableInfo       *callable_info,
                                  ffi_cif              *cif,
                                  GIFFIClosureCallback  callback,
                                  void                 *user_data)
 {
   void *exec_ptr;
   size_t n_args;
   ffi_type **atypes;
   GIClosureWrapper *closure;
   ffi_status status;

   g_return_val_if_fail (callable_info != NULL, FALSE);
   g_return_val_if_fail (cif != NULL, FALSE);
   g_return_val_if_fail (callback != NULL, FALSE);

   closure = ffi_closure_alloc (sizeof (GIClosureWrapper), &exec_ptr);
   if (!closure)
     {
       g_warning ("could not allocate closure");
       return NULL;
     }
   closure->writable_self = closure;
   closure->native_address = exec_ptr;


   atypes = gi_callable_info_get_ffi_arg_types (callable_info, &n_args);
   status = ffi_prep_cif (cif, FFI_DEFAULT_ABI, n_args,
                          gi_callable_info_get_ffi_return_type (callable_info),
                          atypes);
   if (status != FFI_OK)
     {
       g_warning ("ffi_prep_cif failed: %d", status);
       ffi_closure_free (closure);
       return NULL;
     }

   status = ffi_prep_closure_loc (&closure->ffi_closure, cif, callback, user_data, exec_ptr);
   if (status != FFI_OK)
     {
       g_warning ("ffi_prep_closure failed: %d", status);
       ffi_closure_free (closure);
       return NULL;
     }

   return &closure->ffi_closure;
 }

 /**
  * gi_callable_info_get_closure_native_address:
  * @callable_info: a callable info from a typelib
  * @closure: ffi closure
  *
  * Gets callable code from `ffi_closure` prepared by
  * [method@GIRepository.CallableInfo.create_closure].
  *
  * Returns: (transfer none): native address
  * Since: 2.80
  */
 void **
 gi_callable_info_get_closure_native_address (GICallableInfo *callable_info,
                                              ffi_closure    *closure)
 {
   GIClosureWrapper *wrapper = (GIClosureWrapper *)closure;
   return wrapper->native_address;
 }

 /**
  * gi_callable_info_destroy_closure:
  * @callable_info: a callable info from a typelib
  * @closure: (transfer full): ffi closure
  *
  * Frees a `ffi_closure` returned from
  * [method@GIRepository.CallableInfo.create_closure].
  *
  * Since: 2.80
  */
 void
 gi_callable_info_destroy_closure (GICallableInfo *callable_info,
                                   ffi_closure    *closure)
 {
   GIClosureWrapper *wrapper = (GIClosureWrapper *)closure;

   g_free (wrapper->ffi_closure.cif->arg_types);
   ffi_closure_free (wrapper->writable_self);
 }
	/* -- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; --
	* GObject introspection: Helper functions for ffi integration
	*
	* Copyright (C) 2008 Red Hat, Inc
	* Copyright (C) 2005 Matthias Clasen
	*
	* 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 <sys/types.h>

	#include <errno.h>
	#include <string.h>
	#ifdef HAVE_UNISTD_H
	#include <unistd.h>
	#endif
	#include "girffi.h"
	#include "gibaseinfo-private.h"
	#include "girepository.h"
	#include "girepository-private.h"

	static ffi_type *
	gi_type_tag_get_ffi_type_internal (GITypeTag tag,
	gboolean is_pointer,
	gboolean is_enum)
	{
	switch (tag)
	{
	case GI_TYPE_TAG_BOOLEAN:
	return &ffi_type_uint;
	case GI_TYPE_TAG_INT8:
	return &ffi_type_sint8;
	case GI_TYPE_TAG_UINT8:
	return &ffi_type_uint8;
	case GI_TYPE_TAG_INT16:
	return &ffi_type_sint16;
	case GI_TYPE_TAG_UINT16:
	return &ffi_type_uint16;
	case GI_TYPE_TAG_INT32:
	return &ffi_type_sint32;
	case GI_TYPE_TAG_UINT32:
	case GI_TYPE_TAG_UNICHAR:
	return &ffi_type_uint32;
	case GI_TYPE_TAG_INT64:
	return &ffi_type_sint64;
	case GI_TYPE_TAG_UINT64:
	return &ffi_type_uint64;
	case GI_TYPE_TAG_GTYPE:
	#if GLIB_SIZEOF_SIZE_T == 4
	return &ffi_type_uint32;
	#elif GLIB_SIZEOF_SIZE_T == 8
	return &ffi_type_uint64;
	#else
	# error "Unexpected size for size_t: not 4 or 8"
	#endif
	case GI_TYPE_TAG_FLOAT:
	return &ffi_type_float;
	case GI_TYPE_TAG_DOUBLE:
	return &ffi_type_double;
	case GI_TYPE_TAG_UTF8:
	case GI_TYPE_TAG_FILENAME:
	case GI_TYPE_TAG_ARRAY:
	case GI_TYPE_TAG_GLIST:
	case GI_TYPE_TAG_GSLIST:
	case GI_TYPE_TAG_GHASH:
	case GI_TYPE_TAG_ERROR:
	return &ffi_type_pointer;
	case GI_TYPE_TAG_INTERFACE:
	{
	/* We need to handle enums specially:
	* https://bugzilla.gnome.org/show_bug.cgi?id=665150
	*/
	if (!is_enum)
	return &ffi_type_pointer;
	else
	return &ffi_type_sint32;
	}
	case GI_TYPE_TAG_VOID:
	if (is_pointer)
	return &ffi_type_pointer;
	else
	return &ffi_type_void;
	default:
	break;
	}

	g_assert_not_reached ();

	return NULL;
	}

	/**
	* gi_type_tag_get_ffi_type:
	* @type_tag: a #GITypeTag
	* @is_pointer: whether this is a pointer type
	*
	* Get the `ffi_type` corresponding to @type_tag.
	*
	* Returns: (transfer none): an `ffi_type` corresponding to the platform default
	* C ABI for @tag and @is_pointer.
	* Since: 2.80
	*/
	ffi_type *
	gi_type_tag_get_ffi_type (GITypeTag type_tag,
	gboolean is_pointer)
	{
	return gi_type_tag_get_ffi_type_internal (type_tag, is_pointer, FALSE);
	}

	/**
	* gi_type_info_get_ffi_type:
	* @info: a #GITypeInfo
	*
	* Get the `ffi_type` corresponding to @info.
	*
	* Returns: (transfer none): a `ffi_type` corresponding to the platform default
	* C ABI for @info.
	* Since: 2.80
	*/
	ffi_type *
	gi_type_info_get_ffi_type (GITypeInfo *info)
	{
	gboolean is_enum = FALSE;
	GIBaseInfo *iinfo;

	if (gi_type_info_get_tag (info) == GI_TYPE_TAG_INTERFACE)
	{
	iinfo = gi_type_info_get_interface (info);
	switch (gi_base_info_get_info_type (iinfo))
	{
	case GI_INFO_TYPE_ENUM:
	case GI_INFO_TYPE_FLAGS:
	is_enum = TRUE;
	break;
	default:
	break;
	}
	gi_base_info_unref (iinfo);
	}

	return gi_type_tag_get_ffi_type_internal (gi_type_info_get_tag (info), gi_type_info_is_pointer (info), is_enum);
	}

	/**
	* gi_callable_info_get_ffi_arg_types:
	* @callable_info: a callable info from a typelib
	* @n_args_p: (out) (optional): the number of arguments returned
	*
	* Get the `ffi_type`s for the arguments of @callable_info.
	*
	* Returns: (transfer container) (array length=n_args_p): an array of
	* `ffi_type*`. The array itself should be freed using [func@GLib.free] after
	* use.
	* Since: 2.80
	*/
	static ffi_type **
	gi_callable_info_get_ffi_arg_types (GICallableInfo *callable_info,
	size_t *n_args_p)
	{
	ffi_type **arg_types;
	gboolean is_method, throws;
	size_t n_args, n_invoke_args, i, offset;

	g_return_val_if_fail (callable_info != NULL, NULL);

	n_args = gi_callable_info_get_n_args (callable_info);
	is_method = gi_callable_info_is_method (callable_info);
	throws = gi_callable_info_can_throw_gerror (callable_info);
	offset = is_method ? 1 : 0;

	n_invoke_args = n_args;

	if (is_method)
	n_invoke_args++;
	if (throws)
	n_invoke_args++;

	if (n_args_p)
	*n_args_p = n_invoke_args;

	arg_types = (ffi_type *) g_new0 (ffi_type , n_invoke_args + 1);

	if (is_method)
	arg_types[0] = &ffi_type_pointer;
	if (throws)
	arg_types[n_invoke_args - 1] = &ffi_type_pointer;

	for (i = 0; i < n_args; ++i)
	{
	GIArgInfo arg_info;
	GITypeInfo arg_type;

	gi_callable_info_load_arg (callable_info, i, &arg_info);
	gi_arg_info_load_type_info (&arg_info, &arg_type);
	switch (gi_arg_info_get_direction (&arg_info))
	{
	case GI_DIRECTION_IN:
	arg_types[i + offset] = gi_type_info_get_ffi_type (&arg_type);
	break;
	case GI_DIRECTION_OUT:
	case GI_DIRECTION_INOUT:
	arg_types[i + offset] = &ffi_type_pointer;
	break;
	default:
	g_assert_not_reached ();
	}

	gi_base_info_clear (&arg_type);
	gi_base_info_clear (&arg_info);
	}

	arg_types[n_invoke_args] = NULL;

	return arg_types;
	}

	/**
	* gi_callable_info_get_ffi_return_type:
	* @callable_info: a callable info from a typelib
	*
	* Fetches the `ffi_type` for a corresponding return value of
	* a [class@GIRepository.CallableInfo].
	*
	* Returns: (transfer none): the `ffi_type` for the return value
	* Since: 2.80
	*/
	static ffi_type *
	gi_callable_info_get_ffi_return_type (GICallableInfo *callable_info)
	{
	GITypeInfo *return_type;
	ffi_type *return_ffi_type;

	g_return_val_if_fail (callable_info != NULL, NULL);

	return_type = gi_callable_info_get_return_type (callable_info);
	return_ffi_type = gi_type_info_get_ffi_type (return_type);
	gi_base_info_unref((GIBaseInfo*)return_type);

	return return_ffi_type;
	}

	/**
	* gi_function_info_prep_invoker:
	* @info: A #GIFunctionInfo
	* @invoker: (out caller-allocates): Output invoker structure
	* @error: A #GError
	*
	* Initialize the caller-allocated @invoker structure with a cache
	* of information needed to invoke the C function corresponding to
	* @info with the platform’s default ABI.
	*
	* A primary intent of this function is that a dynamic structure allocated
	* by a language binding could contain a [type@GIRepository.FunctionInvoker]
	* structure inside the binding’s function mapping.
	*
	* @invoker must be freed using [method@GIRepository.FunctionInvoker.clear]
	* when it’s finished with.
	*
	* Returns: `TRUE` on success, `FALSE` otherwise with @error set.
	* Since: 2.80
	*/
	gboolean
	gi_function_info_prep_invoker (GIFunctionInfo *info,
	GIFunctionInvoker *invoker,
	GError **error)
	{
	const char *symbol;
	void *addr;

	g_return_val_if_fail (info != NULL, FALSE);
	g_return_val_if_fail (invoker != NULL, FALSE);

	symbol = gi_function_info_get_symbol ((GIFunctionInfo*) info);

	if (!gi_typelib_symbol (gi_base_info_get_typelib ((GIBaseInfo *) info),
	symbol, &addr))
	{
	g_set_error (error,
	GI_INVOKE_ERROR,
	GI_INVOKE_ERROR_SYMBOL_NOT_FOUND,
	"Could not locate %s: %s", symbol, g_module_error ());

	return FALSE;
	}

	return gi_function_invoker_new_for_address (addr, (GICallableInfo *) info, invoker, error);
	}

	/**
	* gi_function_invoker_new_for_address:
	* @addr: The address
	* @info: A #GICallableInfo
	* @invoker: (out caller-allocates): Output invoker structure
	* @error: A #GError
	*
	* Initialize the caller-allocated @invoker structure with a cache
	* of information needed to invoke the C function corresponding to
	* @info with the platform’s default ABI.
	*
	* A primary intent of this function is that a dynamic structure allocated
	* by a language binding could contain a [type@GIRepository.FunctionInvoker]
	* structure inside the binding’s function mapping.
	*
	* Returns: `TRUE` on success, `FALSE` otherwise with @error set.
	* Since: 2.80
	*/
	gboolean
	gi_function_invoker_new_for_address (void *addr,
	GICallableInfo *info,
	GIFunctionInvoker *invoker,
	GError **error)
	{
	ffi_type **atypes;
	size_t n_args;

	g_return_val_if_fail (info != NULL, FALSE);
	g_return_val_if_fail (invoker != NULL, FALSE);

	invoker->native_address = addr;

	atypes = gi_callable_info_get_ffi_arg_types (info, &n_args);

	return ffi_prep_cif (&(invoker->cif), FFI_DEFAULT_ABI, n_args,
	gi_callable_info_get_ffi_return_type (info),
	atypes) == FFI_OK;
	}

	/**
	* gi_function_invoker_clear:
	* @invoker: (transfer none): A #GIFunctionInvoker
	*
	* Release all resources allocated for the internals of @invoker.
	*
	* Callers are responsible for freeing any resources allocated for the structure
	* itself however.
	*
	* Since: 2.80
	*/
	void
	gi_function_invoker_clear (GIFunctionInvoker *invoker)
	{
	g_free (invoker->cif.arg_types);
	}

	typedef struct {
	ffi_closure ffi_closure;
	void *writable_self;
	void *native_address;
	} GIClosureWrapper;

	/**
	* gi_callable_info_create_closure:
	* @callable_info: a callable info from a typelib
	* @cif: a `ffi_cif` structure
	* @callback: the ffi callback
	* @user_data: data to be passed into the callback
	*
	* Prepares a callback for ffi invocation.
	*
	* Returns: (transfer full) (nullable): the `ffi_closure`, or `NULL` on error.
	* The return value should be freed by calling
	* [method@GIRepository.CallableInfo.destroy_closure].
	* Since: 2.80
	*/
	ffi_closure *
	gi_callable_info_create_closure (GICallableInfo *callable_info,
	ffi_cif *cif,
	GIFFIClosureCallback callback,
	void *user_data)
	{
	void *exec_ptr;
	size_t n_args;
	ffi_type **atypes;
	GIClosureWrapper *closure;
	ffi_status status;

	g_return_val_if_fail (callable_info != NULL, FALSE);
	g_return_val_if_fail (cif != NULL, FALSE);
	g_return_val_if_fail (callback != NULL, FALSE);

	closure = ffi_closure_alloc (sizeof (GIClosureWrapper), &exec_ptr);
	if (!closure)
	{
	g_warning ("could not allocate closure");
	return NULL;
	}
	closure->writable_self = closure;
	closure->native_address = exec_ptr;


	atypes = gi_callable_info_get_ffi_arg_types (callable_info, &n_args);
	status = ffi_prep_cif (cif, FFI_DEFAULT_ABI, n_args,
	gi_callable_info_get_ffi_return_type (callable_info),
	atypes);
	if (status != FFI_OK)
	{
	g_warning ("ffi_prep_cif failed: %d", status);
	ffi_closure_free (closure);
	return NULL;
	}

	status = ffi_prep_closure_loc (&closure->ffi_closure, cif, callback, user_data, exec_ptr);
	if (status != FFI_OK)
	{
	g_warning ("ffi_prep_closure failed: %d", status);
	ffi_closure_free (closure);
	return NULL;
	}

	return &closure->ffi_closure;
	}

	/**
	* gi_callable_info_get_closure_native_address:
	* @callable_info: a callable info from a typelib
	* @closure: ffi closure
	*
	* Gets callable code from `ffi_closure` prepared by
	* [method@GIRepository.CallableInfo.create_closure].
	*
	* Returns: (transfer none): native address
	* Since: 2.80
	*/
	void **
	gi_callable_info_get_closure_native_address (GICallableInfo *callable_info,
	ffi_closure *closure)
	{
	GIClosureWrapper wrapper = (GIClosureWrapper )closure;
	return wrapper->native_address;
	}

	/**
	* gi_callable_info_destroy_closure:
	* @callable_info: a callable info from a typelib
	* @closure: (transfer full): ffi closure
	*
	* Frees a `ffi_closure` returned from
	* [method@GIRepository.CallableInfo.create_closure].
	*
	* Since: 2.80
	*/
	void
	gi_callable_info_destroy_closure (GICallableInfo *callable_info,
	ffi_closure *closure)
	{
	GIClosureWrapper wrapper = (GIClosureWrapper )closure;

	g_free (wrapper->ffi_closure.cif->arg_types);
	ffi_closure_free (wrapper->writable_self);
	}