Packets/Packet.hh

   1 // $Id$
   2 //
   3 // Copyright (C) 2007
   4 // Fraunhofer Institute for Open Communication Systems (FOKUS)
   5 // Competence Center NETwork research (NET), St. Augustin, GERMANY
   6 //     Stefan Bund <g0dil@berlios.de>
   7 //
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 2 of the License, or
  11 // (at your option) any later version.
  12 //
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17 //
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the
  20 // Free Software Foundation, Inc.,
  21 // 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  22
  23 /** \file
  24     \brief Packet public header */
  25
  26 #ifndef HH_SENF_Packets_Packet_
  27 #define HH_SENF_Packets_Packet_ 1
  28
  29 // Custom includes
  30 #include <boost/operators.hpp>
  31 #include <boost/utility.hpp>
  32 #include <boost/type_traits/is_integral.hpp>
  33 #include "../Utils/Exception.hh"
  34 #include "../Utils/Tags.hh"
  35 #include "../Utils/safe_bool.hh"
  36 #include "PacketInterpreter.hh"
  37
  38 //#include "Packet.mpp"
  39 ///////////////////////////////hh.p////////////////////////////////////////
  40
  41 namespace senf {
  42
  43     /** \defgroup packet_module Packet Handling
  44
  45         The basic groundwork of the %Packet library is the packet handling:
  46
  47         \li The packet classes provide access to a chain of packet headers (more generically called
  48             interpreters).
  49         \li They automatically manage the required memory resources and the shared packet data.
  50
  51         \section packet_module_chain The Interpreter Chain
  52
  53         The central data structure for a packet is the interpreter chain
  54
  55         \image html structure.png The Interpreter Chain
  56
  57         This image depicts a packet with several headers. Each interpreter is responsible for a
  58         specific sub-range of the complete packet. This range always \e includes the packets payload
  59         (This is, why we call the data structure interpreter and not header: The interpreter is
  60         responsible for interpreting a range of the packet according to a specific protocol), the
  61         packet interpreters are nested inside each other.
  62
  63         For each interpreter, this structure automatically divides the packet into three areas (each
  64         of which are optional): The header, the payload and the trailer. Every packet will have
  65         either a header or a payload section while most don't have a trailer.
  66
  67         As user of the library you always interact with the chain through one (or more) of the
  68         interpreters. The interpreter provides methods to traverse to the following or preceding
  69         header (interpreter) and provides two levels of access to the packet data: Generic low-level
  70         access in the form of an STL compatible sequence and access to the parsed fields which are
  71         provided by the parser associated with the concrete packet type.
  72
  73         \section packet_module_management Resource Management
  74
  75         The interface to the packet library is provided using a handle class (\ref Packet for
  76         generic, protocol agnostic access and \ref ConcretePacket derived from \ref Packet to access
  77         a specific protocol). This handle automatically manages the resources associated with the
  78         packet (the interpreter chain and the data storage holding the packet data). The resources
  79         are automatically released when the last packet handle referencing a specific packet is
  80         destroyed.
  81
  82         \implementation The packet chain is provided on two levels: The internal representation \ref
  83             PacketInterpreterBase and \ref PacketInterpreter which are referenced by the Handle
  84             classes \ref Packet and \ref ConcretePacket. \n
  85             The internal representation classes are pertinent in the sense, that they exist
  86             regardless of the existence of a handle referencing them (as long as the packet
  87             exists). Still the interpreter chain is lazy and packet interpreters beside the first
  88             are only created dynamically when accessed (this is implemented in the handle not in the
  89             internal representation). \n
  90             The packet interpreters make use of a pool allocator. This provides extremely efficient
  91             creation and destruction of packet interpreter's and removes the dynamic memory
  92             management overhead from the packet interpreter management. The packet implementation
  93             class (\ref PacketImpl which holds the packet data itself) however is still dynamically
  94             managed (however there is only a single instance for each packet).
  95      */
  96
  97     template <class PackeType> class ConcretePacket;
  98
  99     ///\addtogroup packet_module
 100     ///@{
 101
 102     /** \brief Main %Packet class
 103
 104         %Packet is the main externally visible class of the packet library. %Packet is a handle into
 105         the internal packet representation. From %Packet you may access the data of that specific
 106         sub-packet/header/interpreter and navigate to the neighboring
 107         sub-packets/headers/interpreters.
 108
 109         %Packet is protocol agnostic. This class only provides non-protocol dependent members. To
 110         access the protocol specific features of a packet (like header fields) the ConcretePacket
 111         class extending %Packet is provided.
 112
 113         \section packet_semantics Semantics
 114
 115         All operations accessing the data of \c this packet in some way will ignore any preceding
 116         packets/headers/interpreters in the chain. It does not matter, whether a given packet is
 117         taken from the middle or the beginning of the chain, all operations (except those explicitly
 118         accessing the chain of course) should work the same.
 119
 120         This especially includes members like clone() or append(): clone() will clone \e only from
 121         \c this packet until the end of the chain, append() will append the given packet \e ignoring
 122         any possibly preceding packets/headers/interpreters.
 123
 124         In the same way, the data() member provides an STL-sequence compatible view of the packet
 125         data. This only includes the data which is part of \c this packet including header, trailer
 126         \e and payload but \e not the headers or trailers of packets \e before \c this packet in the
 127         packet/header/interpreter chain (nonetheless, this data overlaps with the data of other
 128         packets).
 129
 130         Several members are member templates taking an \a OtherPacket template parameter. This
 131         parameter must be the ConcretePacket instantiation associated with some concrete packet type
 132         (protocol). For each implemented protocol, typedefs should be provided for these
 133         instantiations (Example: \ref EthernetPacket is a typedef for
 134         \ref ConcretePacket < \ref EthernetPacketType >).
 135
 136         \see
 137             \ref ConcretePacket for the %type specific interface\n
 138             \ref PacketData for the sequence interface\n
 139             \ref packetparser for a specification of the parser interface
 140       */
 141     class Packet
 142         : public safe_bool<Packet>,
 143           public boost::equality_comparable<Packet>
 144     {
 145     public:
 146         ///////////////////////////////////////////////////////////////////////////
 147         // Types
 148
 149         typedef void type;              ///< Type of the packet.
 150         typedef senf::detail::packet::size_type size_type;
 151                                         ///< Unsigned type to represent packet size
 152         typedef PacketInterpreterBase::factory_t factory_t; ///< Packet factory type (see below)
 153
 154         ///////////////////////////////////////////////////////////////////////////
 155         ///\name Structors and default members
 156         ///@{
 157
 158         // default copy constructor
 159         // default copy assignment
 160         // default destructor
 161
 162         Packet();                       ///< Create uninitialized packet handle
 163                                         /**< An uninitialized handle is in - valid(). It does not
 164                                              allow any operation except assignment and checking for
 165                                              validity. */
 166         Packet clone() const;           ///< Create copy packet
 167                                         /**< clone() will create a complete copy of \c this
 168                                              packet. The returned packet will have the same data and
 169                                              packet chain. It does however not share any data with
 170                                              the original packet. */
 171
 172         // conversion constructors
 173
 174         template <class PacketType>
 175         Packet(ConcretePacket<PacketType> packet); ///< Copy-construct Packet from ConcretePacket
 176                                         /**< This constructor allows to convert an arbitrary
 177                                              ConcretePacket into a general Packet, loosing the
 178                                              protocol specific interface. */
 179
 180         ///@}
 181         ///////////////////////////////////////////////////////////////////////////
 182
 183         ///\name Interpreter chain access
 184         ///@{
 185
 186                                      Packet      next() const;
 187                                         ///< Get next packet in chain
 188                                         /**< \throws InvalidPacketChainException if no next packet
 189                                              exists */
 190                                      Packet      next(NoThrow_t) const;
 191                                         ///< Get next packet in chain
 192                                         /**< \returns in - valid() packet if no next packet
 193                                              exists */
 194         template <class OtherPacket> OtherPacket next() const;
 195                                         ///< Get next packet in chain and cast to \a OtherPacket
 196                                         /**< \throws std::bad_cast if the next() packet is not of
 197                                              type \a OtherPacket
 198                                              \throws InvalidPacketChainException if no next packet
 199                                                  exists */
 200         template <class OtherPacket> OtherPacket next(NoThrow_t) const;
 201                                         ///< Get next packet in chain and cast to \a OtherPacket
 202                                         /**< \throws std::bad_cast if the next() packet is not of
 203                                              type \a OtherPacket
 204                                              \returns in - valid() packet if no next packet
 205                                                  exists */
 206         template <class OtherPacket> OtherPacket find() const;
 207                                         ///< Search chain forward for packet of type \a OtherPacket
 208                                         /**< The search will start with the current packet.
 209                                              \throws InvalidPacketChainException if no packet of
 210                                                  type \a OtherPacket can be found. */
 211         template <class OtherPacket> OtherPacket find(NoThrow_t) const;
 212                                         ///< Search chain forward for packet of type \a OtherPacket
 213                                         /**< The search will start with the current packet.
 214                                              \returns in - valid() packet if no packet of type \a
 215                                                  OtherPacket can be found. */
 216
 217                                      Packet      prev() const;
 218                                         ///< Get previous packet in chain
 219                                         /**< \throws InvalidPacketChainException if no previous
 220                                              packet exists */
 221                                      Packet      prev(NoThrow_t) const;
 222                                         ///< Get previous packet in chain
 223                                         /**< \returns in - valid() packet if no previous packet
 224                                              exists */
 225         template <class OtherPacket> OtherPacket prev() const;
 226                                         ///< Get previous packet in chain and cast to \a OtherPacket
 227                                         /**< \throws std::bad_cast, if the previous packet is not of
 228                                              type \a OtherPacket
 229                                              \throws InvalidPacketChainException if no previous
 230                                                  packet exists */
 231         template <class OtherPacket> OtherPacket prev(NoThrow_t) const;
 232                                         ///< Get previous packet in chain and cast to \a OtherPacket
 233                                         /**< \throws std::bad_cast, if the previous packet is not of
 234                                              type \a OtherPacket
 235                                              \returns in - valid() packet if no previous packet
 236                                                  exists */
 237         template <class OtherPacket> OtherPacket rfind() const;
 238                                         ///< Search chain backwards for packet of type \a OtherPacket
 239                                         /**< The search will start with the current packet.
 240                                              \throws InvalidPacketChainException if no packet of
 241                                                  type \a OtherPacket can be found. */
 242         template <class OtherPacket> OtherPacket rfind(NoThrow_t) const;
 243                                         ///< Search chain backwards for packet of type \a OtherPacket
 244                                         /**< The search will start with the current packet.
 245                                              \returns in - valid() packet if no packet of type \a
 246                                                  OtherPacket can be found. */
 247
 248
 249                                      Packet      first() const;
 250                                         ///< Return first packet in chain
 251         template <class OtherPacket> OtherPacket first() const;
 252                                         ///< Return first packet in chain and cast
 253                                         /**< \throws std::bad_cast if the first() packet is not of
 254                                              type \a OtherPacket */
 255
 256                                      Packet      last() const;
 257                                         ///< Return last packet in chain
 258         template <class OtherPacket> OtherPacket last() const;
 259                                         ///< Return last packet in chain and cast
 260                                         /**< \throws std::bad_cast if the last() packet is not of
 261                                              type \a OtherPacket  */
 262
 263
 264         template <class OtherPacket> OtherPacket parseNextAs() const;
 265                                         ///< Interpret payload of \c this as \a OtherPacket
 266                                         /**< parseNextAs() will throw away the packet chain after
 267                                              the current packet if necessary. It will then parse the
 268                                              payload section of \c this packet as given by \a
 269                                              OtherPacket. The new packet is added to the chain after
 270                                              \c this.
 271                                              \returns new packet instance sharing the same data and
 272                                                  placed after \c this packet in the chain. */
 273                                      Packet      parseNextAs(factory_t factory) const;
 274                                         ///< Interpret payload of \c this as \a factory type packet
 275                                         /**< parseNextAs() will throw away the packet chain after
 276                                              the current packet if necessary. It will then parse the
 277                                              payload section of \c this packet as given by \a
 278                                              factory. The new packet is added to the chain after
 279                                              \c this.
 280                                              \returns new packet instance sharing the same data and
 281                                                  placed after \c this packet in the chain. */
 282
 283         template <class OtherPacket> bool        is() const;
 284                                         ///< Check, whether \c this packet is of the given type
 285         template <class OtherPacket> OtherPacket as() const;
 286                                         ///< Cast current packet to the given type
 287                                         /**< This operations returns a handle to the same packet
 288                                              header/interpreter however cast to the given
 289                                              ConcretePacket type.
 290                                              \throws std::bad_cast if the current packet is not of
 291                                                  type \a OtherPacket */
 292
 293         Packet append(Packet packet) const; ///< Append the given packet to \c this packet
 294                                         /**< This operation will replace the payload section of \c
 295                                              this packet with \a packet. This operation will replace
 296                                              the packet chain after \c this packet with a clone of
 297                                              \a packet and will replace the raw data of the payload
 298                                              of \c this with the raw data of \a packet. \c this
 299                                              packet will not share any date with \a packet.
 300                                              \returns Packet handle to the cloned \a packet, placed
 301                                                  after \c this in the packet/header/interpreter
 302                                                  chain. */
 303
 304         ///@}
 305
 306         ///\name Data access
 307         ///@{
 308
 309         PacketData & data() const;      ///< Access the packets raw data container
 310         size_type size() const;         ///< Return size of packet in bytes
 311                                         /**< This size does \e not include the size of any preceding
 312                                              headers/packets/interpreters. It does however include
 313                                              \c this packets payload. */
 314
 315         ///@}
 316
 317         ///\name Annotations
 318         ///@{
 319
 320         template <class Annotation>
 321         Annotation & annotation();      ///< Get packet annotation
 322                                         /**< This member will retrieve an arbitrary packet
 323                                              annotation. Every annotation is identified by a unique
 324                                              \a Annotation type. This type should \e always be a \c
 325                                              struct.
 326
 327                                              \code
 328                                              struct MyAnnotation {
 329                                                  int value;
 330                                              };
 331
 332                                              senf::Packet p (...);
 333
 334                                              p.annotation<MyAnnotation>().value = 1;
 335                                              \endcode
 336
 337                                              Annotations are shared by all headers / interpreters
 338                                              within a single packet chain.
 339
 340                                              If an annotation is \e not a POD type (more
 341                                              specifically, if it's constructor or destructor is not
 342                                              trivial including base classes and members), the \a
 343                                              Annotation type \e must inherit from
 344                                              senf::ComplexAnnotation. Failing to follow this rule
 345                                              will result in undefined behavior and will probably
 346                                              lead to a program crash.
 347
 348                                              \code
 349                                              struct MyStringAnnotation : senf::ComplexAnnotation {
 350                                                  std::string value;
 351                                              };
 352                                              \endcode
 353                                              (This type is not POD since \c std::string is not POD)
 354
 355                                              \see \ref packet_usage_annotation
 356
 357                                              \implementation The annotation system is implemented
 358                                                  quite efficiently since annotations are stored
 359                                                  within a packet embedded vector of fixed size (the
 360                                                  size is determined automatically at runtime by the
 361                                                  number of different annotations
 362                                                  used). Additionally, non-complex small annotations
 363                                                  require no additional memory management (\c new /
 364                                                  \c delete).
 365
 366                                              \idea Pool the annotation vectors: In the destructor
 367                                                  swap the vector into a vector graveyard (swapping
 368                                                  two vectors is an O(1) no allocation operation). In
 369                                                  the constructor, if there is a vector in the
 370                                                  graveyard, swap it in from there. Of course, it
 371                                                  would be better to do away with the vector and just
 372                                                  allocate the space together with the packet but
 373                                                  that looks quite complicated to do ... especially
 374                                                  considering that the packetimpl itself uses a pool.
 375                                           */
 376
 377         ///@}
 378
 379         ///\name Other methods
 380         ///@{
 381
 382         bool operator==(Packet other) const; ///< Check for packet identity
 383                                         /**< Two packet handles compare equal if they really are the
 384                                              same packet header in the same packet chain. */
 385         bool boolean_test() const;      ///< Check, whether the packet is valid()
 386                                         /**< \see valid() */
 387         bool valid() const;             ///< Check, whether the packet is valid()
 388                                         /**< An in - valid() packet does not allow any operation
 389                                              except checking for validity and assignment. in -
 390                                              valid() packets serve the same role as 0-pointers.
 391
 392                                              This is an alias for boolean_test() which is called
 393                                              when using a packet in a boolean context. */
 394
 395         void finalizeThis();            ///< Update calculated fields
 396                                         /**< The finalize() fammily of members will update
 397                                              calculated packet fields: checksums, size fields and so
 398                                              on. This includes any field, which can be set from
 399                                              other information in the packet. Each concrete packet
 400                                              type should document, which fields are set by
 401                                              finalize().
 402
 403                                              finalizeThis() will \e only process the current
 404                                              header. Even if only changing fields in this protocol,
 405                                              depending on the protocol it may not be enough to
 406                                              finalize this header only. See the packet type
 407                                              documentation. */
 408
 409         template <class Other>
 410         void finalizeTo();              ///< Update calculated fields
 411                                         /**< The finalize() fammily of members will update
 412                                              calculated packet fields: checksums, size fields and so
 413                                              on. This includes any field, which can be set from
 414                                              other information in the packet. Each concrete packet
 415                                              type should document, which fields are set by
 416                                              finalize().
 417
 418                                              finalizeTo() will automatically process all
 419                                              packets/headers/interpreters from the \e first
 420                                              occurrence of packet type \a Other (beginning at \c
 421                                              this packet searching forward towards deeper nested
 422                                              packets) backwards up to \c this.
 423
 424                                              This call is equivalent to
 425                                              \code
 426                                              p.finalizeTo(p.next<Other>())
 427                                              \endcode */
 428
 429         void finalizeTo(Packet other);  ///< Update calculated fields
 430                                         /**< The finalize() fammily of members will update
 431                                              calculated packet fields: checksums, size fields and so
 432                                              on. This includes any field, which can be set from
 433                                              other information in the packet. Each concrete packet
 434                                              type should document, which fields are set by
 435                                              finalize().
 436
 437                                              finalizeTo(other) will automatically process all
 438                                              packets/headers/interpreters beginning at \a other
 439                                              backwards towards outer packets up to \c this. */
 440
 441         void finalizeAll();             ///< Update calculated fields
 442                                         /**< The finalize() fammily of members will update
 443                                              calculated packet fields: checksums, size fields and so
 444                                              on. This includes any field, which can be set from
 445                                              other information in the packet. Each concrete packet
 446                                              type should document, which fields are set by
 447                                              finalize().
 448
 449                                              finalizeAll() will automatically process all
 450                                              packets/headers/interpreters from the end of the chain
 451                                              (the most inner packet) backwards up to \c this.
 452
 453                                              This call is equivalent to
 454                                              \code
 455                                              p.finalizeTo(p.last())
 456                                              \endcode
 457
 458                                              Beware, that finalizeAll() will \e not finalize any
 459                                              headers before \c this, it will \e only process inner
 460                                              headers. */
 461
 462         void dump(std::ostream & os) const; ///< Write out a printable packet representation
 463                                         /**< This method is provided mostly to help debugging packet
 464                                              problems. Each concrete packet should implement a dump
 465                                              method writing out all fields of the packet in a
 466                                              readable representation. dump() will call this member
 467                                              for each packet/header/interpreter in the chain from \c
 468                                              this packet up to the end of the chain. */
 469
 470         TypeIdValue typeId() const;     ///< Get id of \c this packet
 471                                         /**< This value is used e.g. in the packet registry to
 472                                              associate packet types with other information.
 473                                              \returns A type holding the same information as a
 474                                                  type_info object, albeit assignable */
 475         factory_t factory() const;      ///< Return factory instance of \c this packet
 476                                         /**< The returned factory instance can be used to create new
 477                                              packets of the given type without knowing the concrete
 478                                              type of the packet. The value may be stored away for
 479                                              later use if needed. */
 480
 481         ///@}
 482
 483     protected:
 484         explicit Packet(PacketInterpreterBase::ptr packet);
 485
 486         PacketInterpreterBase::ptr ptr() const;
 487
 488     private:
 489         Packet checkNext() const;
 490         Packet checkLast() const;
 491
 492         PacketInterpreterBase::ptr packet_;
 493
 494         template <class PacketType>
 495         friend class ConcretePacket;
 496         friend class PacketParserBase;
 497     };
 498
 499     /** \brief Protocol specific packet handle
 500
 501         The ConcretePacket template class extends Packet to provide protocol/packet type specific
 502         aspects. These are packet constructors and access to the parsed packet fields.
 503
 504         The \c PacketType template argument to ConcretePacket is a protocol specific and internal
 505         policy class which defines the protocol specific behavior. To access a specific type of
 506         packet, the library provides corresponding typedefs of ConcretePacket < \a SomePacketType >
 507         (e.g. \ref EthernetPacket as typedef for \ref ConcretePacket < \ref EthernetPacketType >).
 508
 509         The new members provided by ConcretePacket over packet are mostly comprised of the packet
 510         constructors. These come in three major flavors:
 511
 512         \li The create() family of constructors will create completely new packets.
 513         \li The createAfter() family of constructors will create new packets (with new data for the
 514             packet) \e after a given existing packet.
 515         \li The createBefore()  family of constructors will create new packets (again with new data)
 516             \e before a given existing packet.
 517
 518         Whereas create() will create a completely new packet with it's own chain and data storage,
 519         createAfter() and createBefore() extend a packet with additional
 520         headers/interpreters. createAfter() will set the payload of the given packet to the new
 521         packet whereas createBefore() will create a new packet with the existing packet as it's
 522         payload.
 523
 524         createAfter() differs from Packet::parseNextAs() in that the former creates a new packet \e
 525         replacing any possibly existing data whereas the latter will interpret the already \e
 526         existing data as given by the type argument.
 527
 528         \see \ref PacketTypeBase for a specification of the interface to be provided by the \a
 529             PacketType policy class.
 530       */
 531     template <class PacketType>
 532     class ConcretePacket
 533         : public Packet
 534     {
 535     public:
 536         ///////////////////////////////////////////////////////////////////////////
 537         // Types
 538
 539         typedef PacketType type;
 540         typedef typename PacketType::parser Parser;
 541
 542         ///////////////////////////////////////////////////////////////////////////
 543         ///\name Structors and default members
 544         ///@{
 545
 546         // default copy constructor
 547         // default copy assignment
 548         // default destructor
 549         // no conversion constructors
 550
 551         ConcretePacket();               ///< Create uninitialized packet handle
 552                                         /**< An uninitialized handle is not valid(). It does not
 553                                              allow any operation except assignment and checking for
 554                                              validity. */
 555
 556         static factory_t factory();     ///< Return factory for packets of specific type
 557                                         /**< This \e static member is like Packet::factory() for a
 558                                              specific packet of type \a PacketType */
 559
 560         // Create completely new packet
 561
 562         static ConcretePacket create(); ///< Create default initialized packet
 563                                         /**< The packet will be initialized to it's default empty
 564                                              state. */
 565         static ConcretePacket create(senf::NoInit_t); ///< Create uninitialized empty packet
 566                                         /**< This will create a completely empty and uninitialized
 567                                              packet with <tt>size() == 0</tt>.
 568                                              \param[in] senf::noinit This parameter must always have the
 569                                                  value \c senf::noinit. */
 570         static ConcretePacket create(size_type size); ///< Create default initialized packet
 571                                         /**< This member will create a default initialized packet
 572                                              with the given size. If the size parameter is smaller
 573                                              than the minimum allowed packet size an exception will
 574                                              be thrown.
 575                                              \param[in] size Size of the packet to create in bytes.
 576                                              \throws TruncatedPacketException if \a size is smaller
 577                                                  than the smallest permissible size for this type of
 578                                                  packet. */
 579         static ConcretePacket create(size_type size, senf::NoInit_t);
 580                                         ///< Create uninitialized packet
 581                                         /**< Creates an uninitialized (all-zero) packet of the exact
 582                                              given size.
 583                                              \param[in] size Size of the packet to create in bytes
 584                                              \param[in] senf::noinit This parameter must always have the
 585                                                  value \c senf::noinit. */
 586 #ifndef DOXYGEN
 587         template <class ForwardReadableRange>
 588         static ConcretePacket create(
 589             ForwardReadableRange const & range,
 590             typename boost::disable_if< boost::is_integral<ForwardReadableRange> >::type * = 0);
 591 #else
 592         template <class ForwardReadableRange>
 593         static ConcretePacket create(ForwardReadableRange const & range);
 594                                         ///< Create packet from given data
 595                                         /**< The packet will be created from a copy of the given
 596                                              data. The data from the range will be copied directly
 597                                              into the packet representation. The data will \e not be
 598                                              validated in any way.
 599                                              \param[in] range <a
 600                                                  href="http://www.boost.org/libs/range/index.html">Boost.Range</a>
 601                                                  of data to construct packet from. */
 602 #endif
 603
 604         // Create packet as new packet after a given packet
 605
 606         static ConcretePacket createAfter(Packet packet);
 607                                         ///< Create default initialized packet after \a packet
 608                                         /**< The packet will be initialized to it's default empty
 609                                              state. It will be appended as next header/interpreter
 610                                              after \a packet in that packets interpreter chain.
 611                                              \param[in] packet Packet to append new packet to. */
 612         static ConcretePacket createAfter(Packet packet, senf::NoInit_t);
 613                                         ///< Create uninitialized empty packet after\a packet
 614                                         /**< This will create a completely empty and uninitialized
 615                                              packet with <tt>size() == 0</tt>. It will be appended
 616                                              as next header/interpreter after \a packet in that
 617                                              packets interpreter chain.
 618                                              \param[in] packet Packet to append new packet to.
 619                                              \param[in] senf::noinit This parameter must always have the
 620                                                  value \c senf::noinit. */
 621         static ConcretePacket createAfter(Packet packet, size_type size);
 622                                         ///< Create default initialized packet after \a packet
 623                                         /**< This member will create a default initialized packet
 624                                              with the given size. If the size parameter is smaller
 625                                              than the minimum allowed packet size an exception will
 626                                              be thrown. It will be appended as next
 627                                              header/interpreter after \a packet in that packets
 628                                              interpreter chain.
 629                                              \param[in] packet Packet to append new packet to.
 630                                              \param[in] size Size of the packet to create in bytes.
 631                                              \throws TruncatedPacketException if \a size is smaller
 632                                                  than the smallest permissible size for this type of
 633                                                  packet. */
 634         static ConcretePacket createAfter(Packet packet, size_type size, senf::NoInit_t);
 635                                         ///< Create uninitialized packet after \a packet
 636                                         /**< Creates an uninitialized (all-zero) packet of the exact
 637                                              given size.  It will be appended as next
 638                                              header/interpreter after \a packet in that packets
 639                                              interpreter chain.
 640                                              \param[in] packet Packet to append new packet to.
 641                                              \param[in] size Size of the packet to create in bytes
 642                                              \param[in] senf::noinit This parameter must always have the
 643                                                  value \c senf::noinit. */
 644 #ifndef DOXYGEN
 645         template <class ForwardReadableRange>
 646         static ConcretePacket createAfter(
 647             Packet packet,
 648             ForwardReadableRange const & range,
 649             typename boost::disable_if< boost::is_integral<ForwardReadableRange> >::type * = 0);
 650 #else
 651         template <class ForwardReadableRange>
 652         static ConcretePacket createAfter(Packet packet,
 653                                           ForwardReadableRange const & range);
 654                                         ///< Create packet from given data after \a packet
 655                                         /**< The packet will be created from a copy of the given
 656                                              data. The data from the range will be copied directly
 657                                              into the packet representation. The data will \e not be
 658                                              validated in any way.  It will be appended as next
 659                                              header/interpreter after \a packet in that packets
 660                                              interpreter chain.
 661                                              \param[in] packet Packet to append new packet to.
 662                                              \param[in] range <a
 663                                                  href="http://www.boost.org/libs/range/index.html">Boost.Range</a>
 664                                                  of data to construct packet from. */
 665 #endif
 666
 667         // Create packet as new packet (header) before a given packet
 668
 669         static ConcretePacket createBefore(Packet packet);
 670                                         ///< Create default initialized packet before \a packet
 671                                         /**< The packet will be initialized to it's default empty
 672                                              state. It will be prepended as previous
 673                                              header/interpreter before \a packet in that packets
 674                                              interpreter chain.
 675                                              \param[in] packet Packet to prepend new packet to. */
 676         static ConcretePacket createBefore(Packet packet, senf::NoInit_t);
 677                                         ///< Create uninitialized empty packet before \a packet
 678                                         /**< Creates a completely empty and uninitialized packet. It
 679                                              will be prepended as previous header/interpreter before
 680                                              \a packet in that packets interpreter chain.
 681                                              \param[in] packet Packet to prepend new packet to. */
 682
 683         // Create a clone of the current packet
 684
 685         ConcretePacket clone() const;
 686
 687         ///@}
 688         ///////////////////////////////////////////////////////////////////////////
 689
 690         // Field access
 691
 692         Parser * operator->() const;    ///< Access packet fields
 693                                         /**< This operator allows to access the parsed fields of the
 694                                              packet using the notation <tt>packet->field()</tt>. The
 695                                              fields of the packet are specified by the PacketType's
 696                                              \c parser member.
 697
 698                                              The members are not strictly restricted to simple field
 699                                              access. The parser class may have any member which is
 700                                              needed for full packet access (e.g. checksum validation
 701                                              / recreation ...)
 702                                              \see \ref packetparser for the parser interface. */
 703
 704         Parser parser() const;          ///< Access packet field parser directly
 705                                         /**< Access the parser of the packet. This is the same
 706                                              object returned by the operator->() operator. The
 707                                              operator however does not allow to access this object
 708                                              itself, only it's members.
 709                                              \see \ref packetparser for the parser interface */
 710
 711     protected:
 712
 713     private:
 714         typedef PacketInterpreter<PacketType> interpreter;
 715
 716         ConcretePacket(typename interpreter::ptr packet_);
 717
 718         typename interpreter::ptr ptr() const;
 719
 720         friend class Packet;
 721         friend class PacketInterpreter<PacketType>;
 722     };
 723
 724     ///@}
 725
 726 }
 727
 728 ///////////////////////////////hh.e////////////////////////////////////////
 729 #endif
 730 #if !defined(HH_SENF_Packets_Packets__decls_) && !defined(HH_SENF_Packets_Packet_i_)
 731 #define HH_SENF_Packets_Packet_i_
 732 #include "Packet.cci"
 733 #include "Packet.ct"
 734 #include "Packet.cti"
 735 #endif
 736
 737 \f
 738 // Local Variables:
 739 // mode: c++
 740 // fill-column: 100
 741 // c-file-style: "senf"
 742 // indent-tabs-mode: nil
 743 // ispell-local-dictionary: "american"
 744 // compile-command: "scons -u test"
 745 // comment-column: 40
 746 // End:
 747