src/dbus/qdbuserror.cpp

   1 /****************************************************************************
   2 **
   3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
   4 ** All rights reserved.
   5 ** Contact: Nokia Corporation (qt-info@nokia.com)
   6 **
   7 ** This file is part of the QtDBus module of the Qt Toolkit.
   8 **
   9 ** $QT_BEGIN_LICENSE:LGPL$
  10 ** No Commercial Usage
  11 ** This file contains pre-release code and may not be distributed.
  12 ** You may use this file in accordance with the terms and conditions
  13 ** contained in the Technology Preview License Agreement accompanying
  14 ** this package.
  15 **
  16 ** GNU Lesser General Public License Usage
  17 ** Alternatively, this file may be used under the terms of the GNU Lesser
  18 ** General Public License version 2.1 as published by the Free Software
  19 ** Foundation and appearing in the file LICENSE.LGPL included in the
  20 ** packaging of this file.  Please review the following information to
  21 ** ensure the GNU Lesser General Public License version 2.1 requirements
  22 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
  23 **
  24 ** In addition, as a special exception, Nokia gives you certain additional
  25 ** rights.  These rights are described in the Nokia Qt LGPL Exception
  26 ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
  27 **
  28 ** If you have questions regarding the use of this file, please contact
  29 ** Nokia at qt-info@nokia.com.
  30 **
  31 **
  32 **
  33 **
  34 **
  35 **
  36 **
  37 **
  38 ** $QT_END_LICENSE$
  39 **
  40 ****************************************************************************/
  41
  42 #include "qdbuserror.h"
  43
  44 #include <qdebug.h>
  45 #include <qvarlengtharray.h>
  46
  47 #include <qdbus_symbols_p.h>
  48 #include "qdbusmessage.h"
  49 #include "qdbusmessage_p.h"
  50
  51 QT_BEGIN_NAMESPACE
  52
  53 /*
  54  * Use the following Perl script to generate the error string index list:
  55 ===== PERL SCRIPT ====
  56 print "static const char errorMessages_string[] =\n";
  57 $counter = 0;
  58 $i = 0;
  59 while (<STDIN>) {
  60     chomp;
  61     print "    \"$_\\0\"\n";
  62     $sizes[$i++] = $counter;
  63     $counter += 1 + length $_;
  64 }
  65 print "    \"\\0\";\n\nstatic const int errorMessages_indices[] = {\n    ";
  66 for ($j = 0; $j < $i; ++$j) {
  67     printf "$sizes[$j], ";
  68 }
  69 print "0\n};\n";
  70 ===== PERL SCRIPT ====
  71
  72  * The input data is as follows:
  73 other
  74 org.freedesktop.DBus.Error.Failed
  75 org.freedesktop.DBus.Error.NoMemory
  76 org.freedesktop.DBus.Error.ServiceUnknown
  77 org.freedesktop.DBus.Error.NoReply
  78 org.freedesktop.DBus.Error.BadAddress
  79 org.freedesktop.DBus.Error.NotSupported
  80 org.freedesktop.DBus.Error.LimitsExceeded
  81 org.freedesktop.DBus.Error.AccessDenied
  82 org.freedesktop.DBus.Error.NoServer
  83 org.freedesktop.DBus.Error.Timeout
  84 org.freedesktop.DBus.Error.NoNetwork
  85 org.freedesktop.DBus.Error.AddressInUse
  86 org.freedesktop.DBus.Error.Disconnected
  87 org.freedesktop.DBus.Error.InvalidArgs
  88 org.freedesktop.DBus.Error.UnknownMethod
  89 org.freedesktop.DBus.Error.TimedOut
  90 org.freedesktop.DBus.Error.InvalidSignature
  91 org.freedesktop.DBus.Error.UnknownInterface
  92 com.trolltech.QtDBus.Error.InternalError
  93 org.freedesktop.DBus.Error.UnknownObject
  94 */
  95
  96 // in the same order as KnownErrors!
  97 static const char errorMessages_string[] =
  98     "other\0"
  99     "org.freedesktop.DBus.Error.Failed\0"
 100     "org.freedesktop.DBus.Error.NoMemory\0"
 101     "org.freedesktop.DBus.Error.ServiceUnknown\0"
 102     "org.freedesktop.DBus.Error.NoReply\0"
 103     "org.freedesktop.DBus.Error.BadAddress\0"
 104     "org.freedesktop.DBus.Error.NotSupported\0"
 105     "org.freedesktop.DBus.Error.LimitsExceeded\0"
 106     "org.freedesktop.DBus.Error.AccessDenied\0"
 107     "org.freedesktop.DBus.Error.NoServer\0"
 108     "org.freedesktop.DBus.Error.Timeout\0"
 109     "org.freedesktop.DBus.Error.NoNetwork\0"
 110     "org.freedesktop.DBus.Error.AddressInUse\0"
 111     "org.freedesktop.DBus.Error.Disconnected\0"
 112     "org.freedesktop.DBus.Error.InvalidArgs\0"
 113     "org.freedesktop.DBus.Error.UnknownMethod\0"
 114     "org.freedesktop.DBus.Error.TimedOut\0"
 115     "org.freedesktop.DBus.Error.InvalidSignature\0"
 116     "org.freedesktop.DBus.Error.UnknownInterface\0"
 117     "com.trolltech.QtDBus.Error.InternalError\0"
 118     "org.freedesktop.DBus.Error.UnknownObject\0"
 119     "\0";
 120
 121 static const int errorMessages_indices[] = {
 122        0,    6,   40,   76,  118,  153,  191,  231,
 123      273,  313,  349,  384,  421,  461,  501,  540,
 124      581,  617,  661,  705,  746,    0
 125 };
 126
 127 static const int errorMessages_count = sizeof errorMessages_indices /
 128                                        sizeof errorMessages_indices[0];
 129
 130 static inline const char *get(QDBusError::ErrorType code)
 131 {
 132     int intcode = qBound(0, int(code) - int(QDBusError::Other), errorMessages_count);
 133     return errorMessages_string + errorMessages_indices[intcode];
 134 }
 135
 136 static inline QDBusError::ErrorType get(const char *name)
 137 {
 138     if (!name || !*name)
 139         return QDBusError::NoError;
 140     for (int i = 0; i < errorMessages_count; ++i)
 141         if (strcmp(name, errorMessages_string + errorMessages_indices[i]) == 0)
 142             return QDBusError::ErrorType(i + int(QDBusError::Other));
 143     return QDBusError::Other;
 144 }
 145
 146 /*!
 147     \class QDBusError
 148     \inmodule QtDBus
 149     \since 4.2
 150
 151     \brief The QDBusError class represents an error received from the
 152     D-Bus bus or from remote applications found in the bus.
 153
 154     When dealing with the D-Bus bus service or with remote
 155     applications over D-Bus, a number of error conditions can
 156     happen. This error conditions are sometimes signalled by a
 157     returned error value or by a QDBusError.
 158
 159     C++ and Java exceptions are a valid analogy for D-Bus errors:
 160     instead of returning normally with a return value, remote
 161     applications and the bus may decide to throw an error
 162     condition. However, the QtDBus implementation does not use the C++
 163     exception-throwing mechanism, so you will receive QDBusErrors in
 164     the return reply (see QDBusReply::error()).
 165
 166     QDBusError objects are used to inspect the error name and message
 167     as received from the bus and remote applications. You should not
 168     create such objects yourself to signal error conditions when
 169     called from D-Bus: instead, use QDBusMessage::createError() and
 170     QDBusConnection::send().
 171
 172     \sa QDBusConnection::send(), QDBusMessage, QDBusReply
 173 */
 174
 175 /*!
 176     \enum QDBusError::ErrorType
 177
 178     In order to facilitate verification of the most common D-Bus errors generated by the D-Bus
 179     implementation and by the bus daemon itself, QDBusError can be compared to a set of pre-defined
 180     values:
 181
 182     \value NoError              QDBusError is invalid (i.e., the call succeeded)
 183     \value Other                QDBusError contains an error that is one of the well-known ones
 184     \value Failed               The call failed (\c org.freedesktop.DBus.Error.Failed)
 185     \value NoMemory             Out of memory (\c org.freedesktop.DBus.Error.NoMemory)
 186     \value ServiceUnknown       The called service is not known
 187                                 (\c org.freedesktop.DBus.Error.ServiceUnknown)
 188     \value NoReply              The called method did not reply within the specified timeout
 189                                 (\c org.freedesktop.DBus.Error.NoReply)
 190     \value BadAddress           The address given is not valid
 191                                 (\c org.freedesktop.DBus.Error.BadAddress)
 192     \value NotSupported         The call/operation is not supported
 193                                 (\c org.freedesktop.DBus.Error.NotSupported)
 194     \value LimitsExceeded       The limits allocated to this process/call/connection exceeded the
 195                                 pre-defined values (\c org.freedesktop.DBus.Error.LimitsExceeded)
 196     \value AccessDenied         The call/operation tried to access a resource it isn't allowed to
 197                                 (\c org.freedesktop.DBus.Error.AccessDenied)
 198     \value NoServer             \e {Documentation doesn't say what this is for}
 199                                 (\c org.freedesktop.DBus.Error.NoServer)
 200     \value Timeout              \e {Documentation doesn't say what this is for or how it's used}
 201                                 (\c org.freedesktop.DBus.Error.Timeout)
 202     \value NoNetwork            \e {Documentation doesn't say what this is for}
 203                                 (\c org.freedesktop.DBus.Error.NoNetwork)
 204     \value AddressInUse         QDBusServer tried to bind to an address that is already in use
 205                                 (\c org.freedesktop.DBus.Error.AddressInUse)
 206     \value Disconnected         The call/process/message was sent after QDBusConnection disconnected
 207                                 (\c org.freedesktop.DBus.Error.Disconnected)
 208     \value InvalidArgs          The arguments passed to this call/operation are not valid
 209                                 (\c org.freedesktop.DBus.Error.InvalidArgs)
 210     \value UnknownMethod        The method called was not found in this object/interface with the
 211                                 given parameters (\c org.freedesktop.DBus.Error.UnknownMethod)
 212     \value TimedOut             \e {Documentation doesn't say...}
 213                                 (\c org.freedesktop.DBus.Error.TimedOut)
 214     \value InvalidSignature     The type signature is not valid or compatible
 215                                 (\c org.freedesktop.DBus.Error.InvalidSignature)
 216     \value UnknownInterface     The interface is not known
 217     \value InternalError        An internal error occurred
 218                                 (\c com.trolltech.QtDBus.Error.InternalError)
 219     \value UnknownObject        The remote object could not be found.
 220
 221 */
 222
 223 /*!
 224     \internal
 225     Constructs a QDBusError from a DBusError structure.
 226 */
 227 QDBusError::QDBusError(const DBusError *error)
 228     : code(NoError)
 229 {
 230     if (!error || !q_dbus_error_is_set(error))
 231         return;
 232
 233     code = ::get(error->name);
 234     msg = QString::fromUtf8(error->message);
 235     nm = QString::fromUtf8(error->name);
 236 }
 237
 238 /*!
 239     \internal
 240     Constructs a QDBusError from a QDBusMessage.
 241 */
 242 QDBusError::QDBusError(const QDBusMessage &qdmsg)
 243     : code(NoError)
 244 {
 245     if (qdmsg.type() != QDBusMessage::ErrorMessage)
 246         return;
 247
 248     code = ::get(qdmsg.errorName().toUtf8().constData());
 249     nm = qdmsg.errorName();
 250     msg = qdmsg.errorMessage();
 251 }
 252
 253 /*!
 254     \internal
 255     Constructs a QDBusError from a well-known error code
 256 */
 257 QDBusError::QDBusError(ErrorType error, const QString &mess)
 258     : code(error)
 259 {
 260     nm = QLatin1String(::get(error));
 261     msg = mess;
 262 }
 263
 264 /*!
 265     \internal
 266     Constructs a QDBusError from another QDBusError object
 267 */
 268 QDBusError::QDBusError(const QDBusError &other)
 269         : code(other.code), msg(other.msg), nm(other.nm)
 270 {
 271 }
 272
 273 /*!
 274   \internal
 275   Assignment operator
 276 */
 277
 278 QDBusError &QDBusError::operator=(const QDBusError &other)
 279 {
 280     code = other.code;
 281     msg = other.msg;
 282     nm = other.nm;
 283     return *this;
 284 }
 285
 286 /*!
 287     Returns this error's ErrorType.
 288
 289     \sa ErrorType
 290 */
 291
 292 QDBusError::ErrorType QDBusError::type() const
 293 {
 294     return code;
 295 }
 296
 297 /*!
 298     Returns this error's name. Error names are similar to D-Bus Interface names, like
 299     \c org.freedesktop.DBus.InvalidArgs.
 300
 301     \sa type()
 302 */
 303
 304 QString QDBusError::name() const
 305 {
 306     return nm;
 307 }
 308
 309 /*!
 310     Returns the message that the callee associated with this error. Error messages are
 311     implementation defined and usually contain a human-readable error code, though this does not
 312     mean it is suitable for your end-users.
 313 */
 314
 315 QString QDBusError::message() const
 316 {
 317     return msg;
 318 }
 319
 320 /*!
 321     Returns true if this is a valid error condition (i.e., if there was an error),
 322     otherwise false.
 323 */
 324
 325 bool QDBusError::isValid() const
 326 {
 327     return (code != NoError);
 328 }
 329
 330 /*!
 331     \since 4.3
 332     Returns the error name associated with error condition \a error.
 333 */
 334 QString QDBusError::errorString(ErrorType error)
 335 {
 336     return QLatin1String(::get(error));
 337 }
 338
 339 #ifndef QT_NO_DEBUG_STREAM
 340 QDebug operator<<(QDebug dbg, const QDBusError &msg)
 341 {
 342     dbg.nospace() << "QDBusError(" << msg.name() << ", " << msg.message() << ")";
 343     return dbg.space();
 344 }
 345 #endif
 346
 347 QT_END_NAMESPACE
 348
 349