/**************************************************************************/ /* */ /* Copyright (c) 2001, 2011 NoMachine (http://www.nomachine.com) */ /* Copyright (c) 2008-2014 Oleksandr Shneyder <o.shneyder@phoca-gmbh.de> */ /* Copyright (c) 2014-2016 Ulrich Sibiller <uli42@gmx.de> */ /* Copyright (c) 2014-2016 Mihai Moldovan <ionic@ionic.de> */ /* Copyright (c) 2011-2016 Mike Gabriel <mike.gabriel@das-netzwerkteam.de>*/ /* Copyright (c) 2015-2016 Qindel Group (http://www.qindel.com) */ /* */ /* NXCOMP, NX protocol compression and NX extensions to this software */ /* are copyright of the aforementioned persons and companies. */ /* */ /* Redistribution and use of the present software is allowed according */ /* to terms specified in the file LICENSE.nxcomp which comes in the */ /* source distribution. */ /* */ /* All rights reserved. */ /* */ /* NOTE: This software has received contributions from various other */ /* contributors, only the core maintainers and supporters are listed as */ /* copyright holders. Please contact us, if you feel you should be listed */ /* as copyright holder, as well. */ /* */ /**************************************************************************/ #ifndef Transport_H #define Transport_H #include <zlib.h> #include <errno.h> #include <sys/ioctl.h> #include <sys/types.h> #include <sys/socket.h> #include "Misc.h" #include "Control.h" #include "Types.h" #include "Timestamp.h" #include "Socket.h" // // Set the verbosity level. // #define PANIC #define WARNING #undef TEST #undef DEBUG // // Define this to lock and unlock the // memory-to-memory transport buffers // before they are accessed. The code // is outdated and doesn't work with // the current pthread library. // #undef THREADS // // Define this to know when a socket // is created or destroyed. // #undef REFERENCES // // Size of buffer if not set by user. // #define TRANSPORT_BUFFER_DEFAULT_SIZE 16384 // // Type of transport. // typedef enum { transport_base, transport_proxy, transport_agent, transport_last_tag } T_transport_type; // // This class handles the buffered I/O on // the network sockets. // // // TODO: This class is useful but adds a lot of // overhead. There are many improvements we can // make here: // // - There should be a generic Buffer class, ac- // comodating a list of memory buffers. This // would enable the use of the readv() and // writev() functions to perform the I/O on // the socket. // // - The buffering should be moved to the Write- // Buffer and ReadBuffer classes. By performing // the buffering here and there, we are dupli- // cating a lot of code and are adding a lot // of useless memory copies. // // - Stream compression should be removed. The // proxy should compress the frames based on // the type and should include the length of // the decompressed data in the header of the // packet. Besides avoiding the compression // of packets that cannot be reduced in size, // we would also save the additional memory // allocations due to the fact that we don't // know the size of the decode buffer at the // time we read the packet from the network. // // - The other utilities implemented here, like // the functions forcing a write on the socket // or waiting for more data to become available // should be moved to the Proxy or the Channel // classes. // class Transport { public: // // Member functions. // Transport(int fd); virtual ~Transport(); int fd() const { return fd_; } T_transport_type getType() { return type_; } // // Virtual members redefined by proxy // and 'memory-to-memory' I/O layers. // virtual int read(unsigned char *data, unsigned int size); virtual int write(T_write type, const unsigned char *data, const unsigned int size); virtual int flush(); virtual int drain(int limit, int timeout); virtual void finish() { fullReset(); finish_ = 1; } virtual int length() const { return w_buffer_.length_; } virtual int pending() const { return 0; } virtual int readable() const { return GetBytesReadable(fd_); } virtual int writable() const { return GetBytesWritable(fd_); } virtual int queued() const { return GetBytesQueued(fd_); } virtual int flushable() const { return 0; } virtual int wait(int timeout) const; void setSize(unsigned int initialSize, unsigned int thresholdSize, unsigned int maximumSize); // // Return a pointer to the data // in the read buffer. // virtual unsigned int getPending(unsigned char *&data) { data = NULL; return 0; } virtual void pendingReset() { } virtual void partialReset() { partialReset(w_buffer_); } virtual void fullReset(); int blocked() const { return blocked_; } protected: // // Make room in the buffer to accommodate // at least size bytes. // int resize(T_buffer &buffer, const int &size); void partialReset(T_buffer &buffer) { if (buffer.length_ == 0 && (buffer.data_.size() > initialSize_ || buffer.data_.capacity() > initialSize_)) { fullReset(buffer); } } void fullReset(T_buffer &buffer); // // Data members. // int fd_; int blocked_; int finish_; T_buffer w_buffer_; unsigned int initialSize_; unsigned int thresholdSize_; unsigned int maximumSize_; T_transport_type type_; private: #ifdef REFERENCES static int references_; #endif }; // // This class handles buffered I/O and // compression of the proxy stream. // class ProxyTransport : public Transport { public: ProxyTransport(int fd); virtual ~ProxyTransport(); virtual int read(unsigned char *data, unsigned int size); virtual int write(T_write type, const unsigned char *data, const unsigned int size); virtual int flush(); // // Same as in the base class. // // virtual int drain(int limit, int timeout); // // virtual void finish(); // // // Same as in the base class. // // virtual int length() const // virtual int pending() const { return r_buffer_.length_; } // // Same as in the base class. // // virtual int readable() const; // // virtual int writable() const; // // virtual int queued() const; // virtual int flushable() const { return flush_; } // // Same as in the base class, but // should not be called. // // int drained() const; // // Same as in the base class. // // virtual int wait(int timeout) const; // // Same as in the base class. // // void setSize(unsigned int initialSize, // unsigned int thresholdSize, // unsigned int maximumSize); // virtual unsigned int getPending(unsigned char *&data); virtual void pendingReset() { owner_ = 1; } virtual void partialReset() { if (owner_ == 1) { Transport::partialReset(r_buffer_); } Transport::partialReset(w_buffer_); } virtual void fullReset(); // // Same as in the base class. // // int blocked() const; // protected: int flush_; int owner_; T_buffer r_buffer_; z_stream r_stream_; z_stream w_stream_; private: #ifdef REFERENCES static int references_; #endif }; // // Handle memory-to-memory data transfers between // an agent and the proxy. // class AgentTransport : public Transport { public: AgentTransport(int fd); virtual ~AgentTransport(); virtual int read(unsigned char *data, unsigned int size); virtual int write(T_write type, const unsigned char *data, const unsigned int size); // // These two should never be called. // virtual int flush(); virtual int drain(int limit, int timeout); // // Same as in the base class. // // virtual void finish(); // // // Same as in the base class. // // virtual int length() const // virtual int pending() const { return r_buffer_.length_; } // // These are intended to operate only // on the internal buffers. // virtual int readable() const { return r_buffer_.length_; } virtual int writable() const { return control -> TransportMaximumBufferSize; } virtual int queued() const { return 0; } // // Same as in the base class. // // virtual int flushable() const; // // Same as in the base class, but // should not be called. // // int drained() const; // // // Return immediately or will // block until the timeout. // virtual int wait(int timeout) const { return 0; } // // Same as in the base class. // // void setSize(unsigned int initialSize, // unsigned int thresholdSize, // unsigned int maximumSize); // virtual unsigned int getPending(unsigned char *&data); virtual void pendingReset() { owner_ = 1; } virtual void partialReset() { if (owner_ == 1) { Transport::partialReset(r_buffer_); } Transport::partialReset(w_buffer_); } virtual void fullReset(); // // Same as in the base class. // // int blocked() const; // // // The following are specific of the // memory-to-memory transport. // int enqueue(const char *data, const int size); int dequeue(char *data, int size); int queuable() { // // Always allow the agent to enqueue // more data. // return control -> TransportMaximumBufferSize; } int dequeuable(); protected: // // Lock the buffer to handle reads and // writes safely. // #ifdef THREADS int lockRead(); int lockWrite(); int unlockRead(); int unlockWrite(); #endif // // Data members. // int owner_; T_buffer r_buffer_; // // Mutexes for safe read and write. // #ifdef THREADS pthread_mutex_t m_read_; pthread_mutex_t m_write_; #endif private: #ifdef REFERENCES static int references_; #endif }; #endif /* Transport_H */