X-Git-Url: http://g0dil.de/git?a=blobdiff_plain;f=Packets%2FPacketData.hh;h=2f8a5210727c482aff8b9dc9cd68863635d3e39c;hb=81ffa1c459b96dd44472bcef37e1e373934ee138;hp=f1de1792c0e84681126a2fb8985e3a997f2f3ab4;hpb=47368f306a577d1e46df69a7f729bd3893cbe5e7;p=senf.git diff --git a/Packets/PacketData.hh b/Packets/PacketData.hh index f1de179..2f8a521 100644 --- a/Packets/PacketData.hh +++ b/Packets/PacketData.hh @@ -36,9 +36,33 @@ namespace senf { - /** \brief + /** \brief Packet data STL-sequence view - PacketData only exists to separate out the container interface from PacketInterpreter. + The PacketData class provides an STL-sequence compatible view of the raw packet data. Each + packet/header/interpreter in the chain references the same storage area, presenting a + different (but nested/overlapping) section of the data. + + Whenever the data is manipulated through PacketData, the change is assumed to be within the + data range of that packet: All insertions take place \e inside \c this packet and \e outside + any following packets in the packet chain. + + \warning It is not permissible to change data belonging to a following + packet/header/interpreter even though this data is part of \c this sequence. Doing so + will corrupt the packet data. + + \par + + \warning When accessing packet data via the PacketData interface you are on your own: The + packet is not validated in any way, you bypass all parsers. + + All public members are those of an STL random-access sequence. + + \implementation This class is very tightly integrated with PacketInterpreterBase / + PacketInterpreter. It is separated out of those classes primarily to provide a clean + sequence interface to the library user and not for implementation reasons (it would have + been simpler to implement all these members in PacketInterpreterBase). + + \ingroup packet_module */ class PacketData : boost::noncopyable @@ -47,8 +71,6 @@ namespace senf { /////////////////////////////////////////////////////////////////////////// // Types - typedef senf::detail::packet::smart_pointer::ptr_t ptr; - typedef senf::detail::packet::iterator iterator; typedef senf::detail::packet::const_iterator const_iterator; typedef senf::detail::packet::size_type size_type; @@ -73,10 +95,16 @@ namespace senf { ///\name Sequence interface to raw data ///@{ - iterator begin() const; - iterator end() const; - size_type size() const; - bool empty() const; + iterator begin() const; /**< Returns an random access iterator referring + to the first byte of the packet data. */ + iterator end() const; /**< Returns an random access iterator referring to the + element past the end of the packet data. */ + size_type size() const; ///< Returns the number of bytes in the packet data. + bool empty() const; ///< Test whether the packet data is empty. + /**< Returns whether the packet data is empty, i.e. + whether its size is 0. This function does not modify + the content of the packet data in any way. To clear + the content use clear() */ byte operator[](size_type n) const; byte & operator[](size_type n); @@ -87,27 +115,34 @@ namespace senf { // only academic since what should an empty packet be good for ? void insert(iterator pos, byte v); void insert(iterator pos, size_type n, byte v); +# ifndef DOXYGEN template void insert(iterator pos, InputIterator f, InputIterator l, typename boost::disable_if< boost::is_convertible >::type * = 0); +# else + template + void insert(iterator pos, InputIterator f, InputIterator l); +# endif void erase(iterator pos); void erase(iterator first, iterator last); - void clear(); + void clear(); /**< All bytes of the packet data dropped, + leaving the container with a size of 0. */ void resize(size_type n, byte v=0); ///@} - bool valid(); - protected: PacketData(size_type b, size_type e); + /// Need to make this protected so we can change it in the derived class detail::PacketImpl * impl_; detail::PacketImpl & impl() const; + bool valid(); + private: size_type begin_; size_type end_; @@ -117,9 +152,25 @@ namespace senf { class PacketParserBase; + /** \brief Invalid packet data access + + This exception is signaled whenever an operation tries to access an out-of-bounds data + byte. If the packet has been implemented correctly, this signals a malformed packet. + */ struct TruncatedPacketException : public std::exception { virtual char const * what() const throw() { return "truncated packet"; } }; + /** \brief Re-validating data iterator + + This class is a wrapper around a PacketData::iterator instance. It will revalidate the + iterator on every access. This keeps the iterator valid even when the data container is + resized and thereby possibly relocated. The iterator will always point to the byte at the + same offset from the packets beginning. If data is inserted before this iterators position, + the data pointed to will of course change. + + For this to work, the safe_data_iterator must be initialized with the container to which the + iterator belongs. After this initialization it can be used like any other iterator. + */ class safe_data_iterator : public boost::iterator_facade< safe_data_iterator, PacketData::value_type, @@ -129,18 +180,29 @@ namespace senf { public: typedef PacketData::size_type size_type; - safe_data_iterator(); - explicit safe_data_iterator(PacketData & data); + safe_data_iterator(); ///< Make uninitialized iterator + explicit safe_data_iterator(PacketData & data); + ///< Construct iterator only setting the data container safe_data_iterator(PacketData & data, PacketData::iterator i); + ///< Initialize iterator to given position explicit safe_data_iterator(PacketParserBase const & parser); + ///< Initialize iterator from parser + /**< The iterator will point to the parsers start + position. */ - safe_data_iterator & operator=(PacketData::iterator i); + safe_data_iterator & operator=(PacketData::iterator i); ///< Assign iterator + /**< The iteator \a i must be from the container wo which \c + this iterator has been initialized. */ safe_data_iterator & operator=(PacketParserBase const & parser); - operator PacketData::iterator() const; + ///< Assign iterator from parser + /**< The iterator will point to the parser start + position. */ - bool boolean_test() const; + operator PacketData::iterator() const; ///< Convert to iterator - PacketData & data() const; + bool boolean_test() const; ///< Check, if iterator is initialized + + PacketData & data() const; ///< Access data container private: friend class boost::iterator_core_access; @@ -163,8 +225,8 @@ namespace senf { ///////////////////////////////hh.e//////////////////////////////////////// #endif -#if !defined(HH_PacketData_DeclOnly) &&!defined(HH_PacketData_def) -#define HH_PacketData_def +#if !defined(SENF_PACKETS_DECL_ONLY) && !defined(HH_PacketData_i_) +#define HH_PacketData_i_ #include "PacketData.cci" //#include "PacketData.ct" #include "PacketData.cti" @@ -177,4 +239,7 @@ namespace senf { // c-file-style: "senf" // indent-tabs-mode: nil // ispell-local-dictionary: "american" +// compile-command: "scons -u test" +// comment-column: 40 // End: +