/* GDBus - GLib D-Bus Library

 *

 * Copyright (C) 2008-2010 Red Hat, Inc.

 *

 * 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 2.1 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, see <http://www.gnu.org/licenses/>.

 *

 * Author: David Zeuthen <davidz@redhat.com>

 */

#include "config.h"

#include <stdlib.h>

#include <string.h>

#include "gdbuserror.h"

#include "gioenums.h"

#include "gioenumtypes.h"

#include "gioerror.h"

#include "gdbusprivate.h"

#include "glibintl.h"

/**

 * SECTION:gdbuserror

 * @title: GDBusError

 * @short_description: Mapping D-Bus errors to and from GError

 * @include: gio/gio.h

 *

 * All facilities that return errors from remote methods (such as

 * g_dbus_connection_call_sync()) use #GError to represent both D-Bus

 * errors (e.g. errors returned from the other peer) and locally

 * in-process generated errors.

 *

 * To check if a returned #GError is an error from a remote peer, use

 * g_dbus_error_is_remote_error(). To get the actual D-Bus error name,

 * use g_dbus_error_get_remote_error(). Before presenting an error,

 * always use g_dbus_error_strip_remote_error().

 *

 * In addition, facilities used to return errors to a remote peer also

 * use #GError. See g_dbus_method_invocation_return_error() for

 * discussion about how the D-Bus error name is set.

 *

 * Applications can associate a #GError error domain with a set of D-Bus errors in order to

 * automatically map from D-Bus errors to #GError and back. This

 * is typically done in the function returning the #GQuark for the

 * error domain:

 * |[

 * // foo-bar-error.h:

 *

 * #define FOO_BAR_ERROR (foo_bar_error_quark ())

 * GQuark foo_bar_error_quark (void);

 *

 * typedef enum

 * {

 *   FOO_BAR_ERROR_FAILED,

 *   FOO_BAR_ERROR_ANOTHER_ERROR,

 *   FOO_BAR_ERROR_SOME_THIRD_ERROR,

 *   FOO_BAR_N_ERRORS / *< skip >* /

 * } FooBarError;

 *

 * // foo-bar-error.c:

 *

 * static const GDBusErrorEntry foo_bar_error_entries[] =

 * {

 *   {FOO_BAR_ERROR_FAILED,           "org.project.Foo.Bar.Error.Failed"},

 *   {FOO_BAR_ERROR_ANOTHER_ERROR,    "org.project.Foo.Bar.Error.AnotherError"},

 *   {FOO_BAR_ERROR_SOME_THIRD_ERROR, "org.project.Foo.Bar.Error.SomeThirdError"},

 * };

 *

 * // Ensure that every error code has an associated D-Bus error name

 * G_STATIC_ASSERT (G_N_ELEMENTS (foo_bar_error_entries) == FOO_BAR_N_ERRORS);

 *

 * GQuark

 * foo_bar_error_quark (void)

 * {

 *   static volatile gsize quark_volatile = 0;

 *   g_dbus_error_register_error_domain ("foo-bar-error-quark",

 *                                       &quark_volatile,

 *                                       foo_bar_error_entries,

 *                                       G_N_ELEMENTS (foo_bar_error_entries));

 *   return (GQuark) quark_volatile;

 * }

 * ]|

 * With this setup, a D-Bus peer can transparently pass e.g. %FOO_BAR_ERROR_ANOTHER_ERROR and

 * other peers will see the D-Bus error name org.project.Foo.Bar.Error.AnotherError.

 *

 * If the other peer is using GDBus, and has registered the association with

 * g_dbus_error_register_error_domain() in advance (e.g. by invoking the %FOO_BAR_ERROR quark

 * generation itself in the previous example) the peer will see also %FOO_BAR_ERROR_ANOTHER_ERROR instead

 * of %G_IO_ERROR_DBUS_ERROR. Note that GDBus clients can still recover

 * org.project.Foo.Bar.Error.AnotherError using g_dbus_error_get_remote_error().

 *

 * Note that the %G_DBUS_ERROR error domain is intended only

 * for returning errors from a remote message bus process. Errors

 * generated locally in-process by e.g. #GDBusConnection should use the

 * %G_IO_ERROR domain.

 */

static const GDBusErrorEntry g_dbus_error_entries[] =

{

  {G_DBUS_ERROR_FAILED,                           "org.freedesktop.DBus.Error.Failed"},

  {G_DBUS_ERROR_NO_MEMORY,                        "org.freedesktop.DBus.Error.NoMemory"},

  {G_DBUS_ERROR_SERVICE_UNKNOWN,                  "org.freedesktop.DBus.Error.ServiceUnknown"},

  {G_DBUS_ERROR_NAME_HAS_NO_OWNER,                "org.freedesktop.DBus.Error.NameHasNoOwner"},

  {G_DBUS_ERROR_NO_REPLY,                         "org.freedesktop.DBus.Error.NoReply"},

  {G_DBUS_ERROR_IO_ERROR,                         "org.freedesktop.DBus.Error.IOError"},

  {G_DBUS_ERROR_BAD_ADDRESS,                      "org.freedesktop.DBus.Error.BadAddress"},

  {G_DBUS_ERROR_NOT_SUPPORTED,                    "org.freedesktop.DBus.Error.NotSupported"},

  {G_DBUS_ERROR_LIMITS_EXCEEDED,                  "org.freedesktop.DBus.Error.LimitsExceeded"},

  {G_DBUS_ERROR_ACCESS_DENIED,                    "org.freedesktop.DBus.Error.AccessDenied"},

  {G_DBUS_ERROR_AUTH_FAILED,                      "org.freedesktop.DBus.Error.AuthFailed"},

  {G_DBUS_ERROR_NO_SERVER,                        "org.freedesktop.DBus.Error.NoServer"},

  {G_DBUS_ERROR_TIMEOUT,                          "org.freedesktop.DBus.Error.Timeout"},

  {G_DBUS_ERROR_NO_NETWORK,                       "org.freedesktop.DBus.Error.NoNetwork"},

  {G_DBUS_ERROR_ADDRESS_IN_USE,                   "org.freedesktop.DBus.Error.AddressInUse"},

  {G_DBUS_ERROR_DISCONNECTED,                     "org.freedesktop.DBus.Error.Disconnected"},

  {G_DBUS_ERROR_INVALID_ARGS,                     "org.freedesktop.DBus.Error.InvalidArgs"},

  {G_DBUS_ERROR_FILE_NOT_FOUND,                   "org.freedesktop.DBus.Error.FileNotFound"},

  {G_DBUS_ERROR_FILE_EXISTS,                      "org.freedesktop.DBus.Error.FileExists"},

  {G_DBUS_ERROR_UNKNOWN_METHOD,                   "org.freedesktop.DBus.Error.UnknownMethod"},

  {G_DBUS_ERROR_TIMED_OUT,                        "org.freedesktop.DBus.Error.TimedOut"},

  {G_DBUS_ERROR_MATCH_RULE_NOT_FOUND,             "org.freedesktop.DBus.Error.MatchRuleNotFound"},

  {G_DBUS_ERROR_MATCH_RULE_INVALID,               "org.freedesktop.DBus.Error.MatchRuleInvalid"},

  {G_DBUS_ERROR_SPAWN_EXEC_FAILED,                "org.freedesktop.DBus.Error.Spawn.ExecFailed"},

  {G_DBUS_ERROR_SPAWN_FORK_FAILED,                "org.freedesktop.DBus.Error.Spawn.ForkFailed"},

  {G_DBUS_ERROR_SPAWN_CHILD_EXITED,               "org.freedesktop.DBus.Error.Spawn.ChildExited"},

  {G_DBUS_ERROR_SPAWN_CHILD_SIGNALED,             "org.freedesktop.DBus.Error.Spawn.ChildSignaled"},

  {G_DBUS_ERROR_SPAWN_FAILED,                     "org.freedesktop.DBus.Error.Spawn.Failed"},

  {G_DBUS_ERROR_SPAWN_SETUP_FAILED,               "org.freedesktop.DBus.Error.Spawn.FailedToSetup"},

  {G_DBUS_ERROR_SPAWN_CONFIG_INVALID,             "org.freedesktop.DBus.Error.Spawn.ConfigInvalid"},

  {G_DBUS_ERROR_SPAWN_SERVICE_INVALID,            "org.freedesktop.DBus.Error.Spawn.ServiceNotValid"},

  {G_DBUS_ERROR_SPAWN_SERVICE_NOT_FOUND,          "org.freedesktop.DBus.Error.Spawn.ServiceNotFound"},

  {G_DBUS_ERROR_SPAWN_PERMISSIONS_INVALID,        "org.freedesktop.DBus.Error.Spawn.PermissionsInvalid"},

  {G_DBUS_ERROR_SPAWN_FILE_INVALID,               "org.freedesktop.DBus.Error.Spawn.FileInvalid"},

  {G_DBUS_ERROR_SPAWN_NO_MEMORY,                  "org.freedesktop.DBus.Error.Spawn.NoMemory"},

  {G_DBUS_ERROR_UNIX_PROCESS_ID_UNKNOWN,          "org.freedesktop.DBus.Error.UnixProcessIdUnknown"},

  {G_DBUS_ERROR_INVALID_SIGNATURE,                "org.freedesktop.DBus.Error.InvalidSignature"},

  {G_DBUS_ERROR_INVALID_FILE_CONTENT,             "org.freedesktop.DBus.Error.InvalidFileContent"},

  {G_DBUS_ERROR_SELINUX_SECURITY_CONTEXT_UNKNOWN, "org.freedesktop.DBus.Error.SELinuxSecurityContextUnknown"},

  {G_DBUS_ERROR_ADT_AUDIT_DATA_UNKNOWN,           "org.freedesktop.DBus.Error.AdtAuditDataUnknown"},

  {G_DBUS_ERROR_OBJECT_PATH_IN_USE,               "org.freedesktop.DBus.Error.ObjectPathInUse"},

  {G_DBUS_ERROR_UNKNOWN_OBJECT,                   "org.freedesktop.DBus.Error.UnknownObject"},

  {G_DBUS_ERROR_UNKNOWN_INTERFACE,                "org.freedesktop.DBus.Error.UnknownInterface"},

  {G_DBUS_ERROR_UNKNOWN_PROPERTY,                 "org.freedesktop.DBus.Error.UnknownProperty"},

  {G_DBUS_ERROR_PROPERTY_READ_ONLY,               "org.freedesktop.DBus.Error.PropertyReadOnly"},

};

GQuark

g_dbus_error_quark (void)

{

  G_STATIC_ASSERT (G_N_ELEMENTS (g_dbus_error_entries) - 1 == G_DBUS_ERROR_PROPERTY_READ_ONLY);

  static volatile gsize quark_volatile = 0;

  g_dbus_error_register_error_domain ("g-dbus-error-quark",

                                      &quark_volatile,

                                      g_dbus_error_entries,

                                      G_N_ELEMENTS (g_dbus_error_entries));

  return (GQuark) quark_volatile;

}

/**

 * g_dbus_error_register_error_domain:

 * @error_domain_quark_name: The error domain name.

 * @quark_volatile: A pointer where to store the #GQuark.

 * @entries: (array length=num_entries): A pointer to @num_entries #GDBusErrorEntry struct items.

 * @num_entries: Number of items to register.

 *

 * Helper function for associating a #GError error domain with D-Bus error names.

 *

 * Since: 2.26

 */

void

g_dbus_error_register_error_domain (const gchar           *error_domain_quark_name,

                                    volatile gsize        *quark_volatile,

                                    const GDBusErrorEntry *entries,

                                    guint                  num_entries)

{

  g_return_if_fail (error_domain_quark_name != NULL);

  g_return_if_fail (quark_volatile != NULL);

  g_return_if_fail (entries != NULL);

  g_return_if_fail (num_entries > 0);

  if (g_once_init_enter (quark_volatile))

    {

      guint n;

      GQuark quark;

      quark = g_quark_from_static_string (error_domain_quark_name);

      for (n = 0; n < num_entries; n++)

        {

          g_warn_if_fail (g_dbus_error_register_error (quark,

                                                       entries[n].error_code,

                                                       entries[n].dbus_error_name));

        }

      g_once_init_leave (quark_volatile, quark);

    }

}

static gboolean

_g_dbus_error_decode_gerror (const gchar *dbus_name,

                             GQuark      *out_error_domain,

                             gint        *out_error_code)

{

  gboolean ret;

  guint n;

  GString *s;

  gchar *domain_quark_string;

  ret = FALSE;

  s = NULL;

  if (g_str_has_prefix (dbus_name, "org.gtk.GDBus.UnmappedGError.Quark._"))

    {

      s = g_string_new (NULL);

      for (n = sizeof "org.gtk.GDBus.UnmappedGError.Quark._" - 1;

           dbus_name[n] != '.' && dbus_name[n] != '\0';

           n++)

        {

          if (g_ascii_isalnum (dbus_name[n]))

            {

              g_string_append_c (s, dbus_name[n]);

            }

          else if (dbus_name[n] == '_')

            {

              guint nibble_top;

              guint nibble_bottom;

              n++;

              nibble_top = dbus_name[n];

              if (nibble_top >= '0' && nibble_top <= '9')

                nibble_top -= '0';

              else if (nibble_top >= 'a' && nibble_top <= 'f')

                nibble_top -= ('a' - 10);

              else

                goto not_mapped;

              n++;

              nibble_bottom = dbus_name[n];

              if (nibble_bottom >= '0' && nibble_bottom <= '9')

                nibble_bottom -= '0';

              else if (nibble_bottom >= 'a' && nibble_bottom <= 'f')

                nibble_bottom -= ('a' - 10);

              else

                goto not_mapped;

              g_string_append_c (s, (nibble_top<<4) | nibble_bottom);

            }

          else

            {

              goto not_mapped;

            }

        }

      if (!g_str_has_prefix (dbus_name + n, ".Code"))

        goto not_mapped;

      domain_quark_string = g_string_free (s, FALSE);

      s = NULL;

      if (out_error_domain != NULL)

        *out_error_domain = g_quark_from_string (domain_quark_string);

      g_free (domain_quark_string);

      if (out_error_code != NULL)

        *out_error_code = atoi (dbus_name + n + sizeof ".Code" - 1);

      ret = TRUE;

    }

 not_mapped:

  if (s != NULL)

    g_string_free (s, TRUE);

  return ret;

}

/* ---------------------------------------------------------------------------------------------------- */

typedef struct

{

  GQuark error_domain;

  gint   error_code;

} QuarkCodePair;

static guint

quark_code_pair_hash_func (const QuarkCodePair *pair)

{

  gint val;

  val = pair->error_domain + pair->error_code;

  return g_int_hash (&val;;

}

static gboolean

quark_code_pair_equal_func (const QuarkCodePair *a,

                            const QuarkCodePair *b)

{

  return (a->error_domain == b->error_domain) && (a->error_code == b->error_code);

}

typedef struct

{

  QuarkCodePair pair;

  gchar *dbus_error_name;

} RegisteredError;

static void

registered_error_free (RegisteredError *re)

{

  g_free (re->dbus_error_name);

  g_free (re);

}

G_LOCK_DEFINE_STATIC (error_lock);

/* maps from QuarkCodePair* -> RegisteredError* */

static GHashTable *quark_code_pair_to_re = NULL;

/* maps from gchar* -> RegisteredError* */

static GHashTable *dbus_error_name_to_re = NULL;

/**

 * g_dbus_error_register_error:

 * @error_domain: A #GQuark for a error domain.

 * @error_code: An error code.

 * @dbus_error_name: A D-Bus error name.

 *

 * Creates an association to map between @dbus_error_name and

 * #GErrors specified by @error_domain and @error_code.

 *

 * This is typically done in the routine that returns the #GQuark for

 * an error domain.

 *

 * Returns: %TRUE if the association was created, %FALSE if it already

 * exists.

 *

 * Since: 2.26

 */

gboolean

g_dbus_error_register_error (GQuark       error_domain,

                             gint         error_code,

                             const gchar *dbus_error_name)

{

  gboolean ret;

  QuarkCodePair pair;

  RegisteredError *re;

  g_return_val_if_fail (dbus_error_name != NULL, FALSE);

  ret = FALSE;

  G_LOCK (error_lock);

  if (quark_code_pair_to_re == NULL)

    {

      g_assert (dbus_error_name_to_re == NULL); /* check invariant */

      quark_code_pair_to_re = g_hash_table_new ((GHashFunc) quark_code_pair_hash_func,

                                                (GEqualFunc) quark_code_pair_equal_func);

      dbus_error_name_to_re = g_hash_table_new_full (g_str_hash,

                                                     g_str_equal,

                                                     NULL,

                                                     (GDestroyNotify) registered_error_free);

    }

  if (g_hash_table_lookup (dbus_error_name_to_re, dbus_error_name) != NULL)

    goto out;

  pair.error_domain = error_domain;

  pair.error_code = error_code;

  if (g_hash_table_lookup (quark_code_pair_to_re, &pair) != NULL)

    goto out;

  re = g_new0 (RegisteredError, 1);

  re->pair = pair;

  re->dbus_error_name = g_strdup (dbus_error_name);

  g_hash_table_insert (quark_code_pair_to_re, &(re->pair), re);

  g_hash_table_insert (dbus_error_name_to_re, re->dbus_error_name, re);

  ret = TRUE;

 out:

  G_UNLOCK (error_lock);

  return ret;

}

/**

 * g_dbus_error_unregister_error:

 * @error_domain: A #GQuark for a error domain.

 * @error_code: An error code.

 * @dbus_error_name: A D-Bus error name.

 *

 * Destroys an association previously set up with g_dbus_error_register_error().

 *

 * Returns: %TRUE if the association was destroyed, %FALSE if it wasn't found.

 *

 * Since: 2.26

 */

gboolean

g_dbus_error_unregister_error (GQuark       error_domain,

                               gint         error_code,

                               const gchar *dbus_error_name)

{

  gboolean ret;

  RegisteredError *re;

  guint hash_size;

  g_return_val_if_fail (dbus_error_name != NULL, FALSE);

  ret = FALSE;

  G_LOCK (error_lock);

  if (dbus_error_name_to_re == NULL)

    {

      g_assert (quark_code_pair_to_re == NULL); /* check invariant */

      goto out;

    }

  re = g_hash_table_lookup (dbus_error_name_to_re, dbus_error_name);

  if (re == NULL)

    {

      QuarkCodePair pair;

      pair.error_domain = error_domain;

      pair.error_code = error_code;

      g_warn_if_fail (g_hash_table_lookup (quark_code_pair_to_re, &pair) == NULL); /* check invariant */

      goto out;

    }

  ret = TRUE;

  g_warn_if_fail (g_hash_table_lookup (quark_code_pair_to_re, &(re->pair)) == re); /* check invariant */

  g_warn_if_fail (g_hash_table_remove (quark_code_pair_to_re, &(re->pair)));

  g_warn_if_fail (g_hash_table_remove (dbus_error_name_to_re, re->dbus_error_name));

  /* destroy hashes if empty */

  hash_size = g_hash_table_size (dbus_error_name_to_re);

  if (hash_size == 0)

    {

      g_warn_if_fail (g_hash_table_size (quark_code_pair_to_re) == 0); /* check invariant */

      g_hash_table_unref (dbus_error_name_to_re);

      dbus_error_name_to_re = NULL;

      g_hash_table_unref (quark_code_pair_to_re);

      quark_code_pair_to_re = NULL;

    }

  else

    {

      g_warn_if_fail (g_hash_table_size (quark_code_pair_to_re) == hash_size); /* check invariant */

    }

 out:

  G_UNLOCK (error_lock);

  return ret;

}

/* ---------------------------------------------------------------------------------------------------- */

/**

 * g_dbus_error_is_remote_error:

 * @error: A #GError.

 *

 * Checks if @error represents an error received via D-Bus from a remote peer. If so,

 * use g_dbus_error_get_remote_error() to get the name of the error.

 *

 * Returns: %TRUE if @error represents an error from a remote peer,

 * %FALSE otherwise.

 *

 * Since: 2.26

 */

gboolean

g_dbus_error_is_remote_error (const GError *error)

{

  g_return_val_if_fail (error != NULL, FALSE);

  return g_str_has_prefix (error->message, "GDBus.Error:");

}

/**

 * g_dbus_error_get_remote_error:

 * @error: a #GError

 *

 * Gets the D-Bus error name used for @error, if any.

 *

 * This function is guaranteed to return a D-Bus error name for all

 * #GErrors returned from functions handling remote method calls

 * (e.g. g_dbus_connection_call_finish()) unless

 * g_dbus_error_strip_remote_error() has been used on @error.

 *

 * Returns: an allocated string or %NULL if the D-Bus error name

 *     could not be found. Free with g_free().

 *

 * Since: 2.26

 */

gchar *

g_dbus_error_get_remote_error (const GError *error)

{

  RegisteredError *re;

  gchar *ret;

  g_return_val_if_fail (error != NULL, NULL);

  /* Ensure that e.g. G_DBUS_ERROR is registered using g_dbus_error_register_error() */

  _g_dbus_initialize ();

  ret = NULL;

  G_LOCK (error_lock);

  re = NULL;

  if (quark_code_pair_to_re != NULL)

    {

      QuarkCodePair pair;

      pair.error_domain = error->domain;

      pair.error_code = error->code;

      g_assert (dbus_error_name_to_re != NULL); /* check invariant */

      re = g_hash_table_lookup (quark_code_pair_to_re, &pair);

    }

  if (re != NULL)

    {

      ret = g_strdup (re->dbus_error_name);

    }

  else

    {

      if (g_str_has_prefix (error->message, "GDBus.Error:"))

        {

          const gchar *begin;

          const gchar *end;

          begin = error->message + sizeof ("GDBus.Error:") -1;

          end = strstr (begin, ":");

          if (end != NULL && end[1] == ' ')

            {

              ret = g_strndup (begin, end - begin);

            }

        }

    }

  G_UNLOCK (error_lock);

  return ret;

}

/* ---------------------------------------------------------------------------------------------------- */

/**

 * g_dbus_error_new_for_dbus_error:

 * @dbus_error_name: D-Bus error name.

 * @dbus_error_message: D-Bus error message.

 *

 * Creates a #GError based on the contents of @dbus_error_name and

 * @dbus_error_message.

 *

 * Errors registered with g_dbus_error_register_error() will be looked

 * up using @dbus_error_name and if a match is found, the error domain

 * and code is used. Applications can use g_dbus_error_get_remote_error()

 * to recover @dbus_error_name.

 *

 * If a match against a registered error is not found and the D-Bus

 * error name is in a form as returned by g_dbus_error_encode_gerror()

 * the error domain and code encoded in the name is used to

 * create the #GError. Also, @dbus_error_name is added to the error message

 * such that it can be recovered with g_dbus_error_get_remote_error().

 *

 * Otherwise, a #GError with the error code %G_IO_ERROR_DBUS_ERROR

 * in the #G_IO_ERROR error domain is returned. Also, @dbus_error_name is

 * added to the error message such that it can be recovered with

 * g_dbus_error_get_remote_error().

 *

 * In all three cases, @dbus_error_name can always be recovered from the

 * returned #GError using the g_dbus_error_get_remote_error() function

 * (unless g_dbus_error_strip_remote_error() hasn't been used on the returned error).

 *

 * This function is typically only used in object mappings to prepare

 * #GError instances for applications. Regular applications should not use

 * it.

 *

 * Returns: An allocated #GError. Free with g_error_free().

 *

 * Since: 2.26

 */

GError *

g_dbus_error_new_for_dbus_error (const gchar *dbus_error_name,

                                 const gchar *dbus_error_message)

{

  GError *error;

  RegisteredError *re;

  g_return_val_if_fail (dbus_error_name != NULL, NULL);

  g_return_val_if_fail (dbus_error_message != NULL, NULL);

  /* Ensure that e.g. G_DBUS_ERROR is registered using g_dbus_error_register_error() */

  _g_dbus_initialize ();

  G_LOCK (error_lock);

  re = NULL;

  if (dbus_error_name_to_re != NULL)

    {

      g_assert (quark_code_pair_to_re != NULL); /* check invariant */

      re = g_hash_table_lookup (dbus_error_name_to_re, dbus_error_name);

    }

  if (re != NULL)

    {

      error = g_error_new (re->pair.error_domain,

                           re->pair.error_code,

                           "GDBus.Error:%s: %s",

                           dbus_error_name,

                           dbus_error_message);

    }

  else

    {

      GQuark error_domain = 0;

      gint error_code = 0;

      if (_g_dbus_error_decode_gerror (dbus_error_name,

                                       &error_domain,

                                       &error_code))

        {

          error = g_error_new (error_domain,

                               error_code,

                               "GDBus.Error:%s: %s",

                               dbus_error_name,

                               dbus_error_message);

        }

      else

        {

          error = g_error_new (G_IO_ERROR,

                               G_IO_ERROR_DBUS_ERROR,

                               "GDBus.Error:%s: %s",

                               dbus_error_name,

                               dbus_error_message);

        }

    }

  G_UNLOCK (error_lock);

  return error;

}

/**

 * g_dbus_error_set_dbus_error:

 * @error: A pointer to a #GError or %NULL.

 * @dbus_error_name: D-Bus error name.

 * @dbus_error_message: D-Bus error message.

 * @format: (nullable): printf()-style format to prepend to @dbus_error_message or %NULL.

 * @...: Arguments for @format.

 *

 * Does nothing if @error is %NULL. Otherwise sets *@error to

 * a new #GError created with g_dbus_error_new_for_dbus_error()

 * with @dbus_error_message prepend with @format (unless %NULL).

 *

 * Since: 2.26

 */

void

g_dbus_error_set_dbus_error (GError      **error,

                             const gchar  *dbus_error_name,

                             const gchar  *dbus_error_message,

                             const gchar  *format,

                             ...)

{

  g_return_if_fail (error == NULL || *error == NULL);

  g_return_if_fail (dbus_error_name != NULL);

  g_return_if_fail (dbus_error_message != NULL);

  if (error == NULL)

    return;

  if (format == NULL)

    {

      *error = g_dbus_error_new_for_dbus_error (dbus_error_name, dbus_error_message);

    }

  else

    {

      va_list var_args;

      va_start (var_args, format);

      g_dbus_error_set_dbus_error_valist (error,

                                          dbus_error_name,

                                          dbus_error_message,

                                          format,

                                          var_args);

      va_end (var_args);

    }

}

/**

 * g_dbus_error_set_dbus_error_valist:

 * @error: A pointer to a #GError or %NULL.

 * @dbus_error_name: D-Bus error name.

 * @dbus_error_message: D-Bus error message.

 * @format: (nullable): printf()-style format to prepend to @dbus_error_message or %NULL.

 * @var_args: Arguments for @format.

 *

 * Like g_dbus_error_set_dbus_error() but intended for language bindings.

 *

 * Since: 2.26

 */

void

g_dbus_error_set_dbus_error_valist (GError      **error,

                                    const gchar  *dbus_error_name,

                                    const gchar  *dbus_error_message,

                                    const gchar  *format,

                                    va_list       var_args)

{

  g_return_if_fail (error == NULL || *error == NULL);

  g_return_if_fail (dbus_error_name != NULL);

  g_return_if_fail (dbus_error_message != NULL);

  if (error == NULL)

    return;

  if (format != NULL)

    {

      gchar *message;

      gchar *s;

      message = g_strdup_vprintf (format, var_args);

      s = g_strdup_printf ("%s: %s", message, dbus_error_message);

      *error = g_dbus_error_new_for_dbus_error (dbus_error_name, s);

      g_free (s);

      g_free (message);

    }

  else

    {

      *error = g_dbus_error_new_for_dbus_error (dbus_error_name, dbus_error_message);

    }

}

/**

 * g_dbus_error_strip_remote_error:

 * @error: A #GError.

 *

 * Looks for extra information in the error message used to recover

 * the D-Bus error name and strips it if found. If stripped, the

 * message field in @error will correspond exactly to what was

 * received on the wire.

 *

 * This is typically used when presenting errors to the end user.

 *

 * Returns: %TRUE if information was stripped, %FALSE otherwise.

 *

 * Since: 2.26

 */

gboolean

g_dbus_error_strip_remote_error (GError *error)

{

  gboolean ret;

  g_return_val_if_fail (error != NULL, FALSE);

  ret = FALSE;

  if (g_str_has_prefix (error->message, "GDBus.Error:"))

    {

      const gchar *begin;

      const gchar *end;

      gchar *new_message;

      begin = error->message + sizeof ("GDBus.Error:") -1;

      end = strstr (begin, ":");

      if (end != NULL && end[1] == ' ')

        {

          new_message = g_strdup (end + 2);

          g_free (error->message);

          error->message = new_message;

          ret = TRUE;

        }

    }

  return ret;

}

/**

 * g_dbus_error_encode_gerror:

 * @error: A #GError.

 *

 * Creates a D-Bus error name to use for @error. If @error matches

 * a registered error (cf. g_dbus_error_register_error()), the corresponding

 * D-Bus error name will be returned.

 *

 * Otherwise the a name of the form

 * `org.gtk.GDBus.UnmappedGError.Quark._ESCAPED_QUARK_NAME.Code_ERROR_CODE`

 * will be used. This allows other GDBus applications to map the error

 * on the wire back to a #GError using g_dbus_error_new_for_dbus_error().

 *

 * This function is typically only used in object mappings to put a

 * #GError on the wire. Regular applications should not use it.

 *

 * Returns: A D-Bus error name (never %NULL). Free with g_free().

 *

 * Since: 2.26

 */

gchar *

g_dbus_error_encode_gerror (const GError *error)

{

  RegisteredError *re;

  gchar *error_name;

  g_return_val_if_fail (error != NULL, NULL);

  /* Ensure that e.g. G_DBUS_ERROR is registered using g_dbus_error_register_error() */

  _g_dbus_initialize ();

  error_name = NULL;

  G_LOCK (error_lock);

  re = NULL;

  if (quark_code_pair_to_re != NULL)

    {

      QuarkCodePair pair;

      pair.error_domain = error->domain;

      pair.error_code = error->code;

      g_assert (dbus_error_name_to_re != NULL); /* check invariant */

      re = g_hash_table_lookup (quark_code_pair_to_re, &pair);

    }

  if (re != NULL)

    {

      error_name = g_strdup (re->dbus_error_name);

      G_UNLOCK (error_lock);

    }

  else

    {

      const gchar *domain_as_string;

      GString *s;

      guint n;

      G_UNLOCK (error_lock);

      /* We can't make a lot of assumptions about what domain_as_string

       * looks like and D-Bus is extremely picky about error names so

       * hex-encode it for transport across the wire.

       */

      domain_as_string = g_quark_to_string (error->domain);

      /* 0 is not a domain; neither are non-quark integers */

      g_return_val_if_fail (domain_as_string != NULL, NULL);

      s = g_string_new ("org.gtk.GDBus.UnmappedGError.Quark._");

      for (n = 0; domain_as_string[n] != 0; n++)

        {

          gint c = domain_as_string[n];

          if (g_ascii_isalnum (c))

            {

              g_string_append_c (s, c);

            }

          else

            {

              guint nibble_top;

              guint nibble_bottom;

              g_string_append_c (s, '_');

              nibble_top = ((int) domain_as_string[n]) >> 4;

              nibble_bottom = ((int) domain_as_string[n]) & 0x0f;

              if (nibble_top < 10)

                nibble_top += '0';

              else

                nibble_top += 'a' - 10;

              if (nibble_bottom < 10)

                nibble_bottom += '0';

              else

                nibble_bottom += 'a' - 10;

              g_string_append_c (s, nibble_top);

              g_string_append_c (s, nibble_bottom);

            }

        }

      g_string_append_printf (s, ".Code%d", error->code);