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Diffstat (limited to 'nxcomp/Channel.h')
| -rw-r--r-- | nxcomp/Channel.h | 656 |
1 files changed, 656 insertions, 0 deletions
diff --git a/nxcomp/Channel.h b/nxcomp/Channel.h new file mode 100644 index 000000000..68fe1d7e9 --- /dev/null +++ b/nxcomp/Channel.h @@ -0,0 +1,656 @@ +/**************************************************************************/ +/* */ +/* Copyright (c) 2001, 2010 NoMachine, http://www.nomachine.com/. */ +/* */ +/* NXCOMP, NX protocol compression and NX extensions to this software */ +/* are copyright of NoMachine. Redistribution and use of the present */ +/* software is allowed according to terms specified in the file LICENSE */ +/* which comes in the source distribution. */ +/* */ +/* Check http://www.nomachine.com/licensing.html for applicability. */ +/* */ +/* NX and NoMachine are trademarks of Medialogic S.p.A. */ +/* */ +/* All rights reserved. */ +/* */ +/**************************************************************************/ + +#ifndef Channel_H +#define Channel_H + +#include "Transport.h" + +#include "WriteBuffer.h" + +#include "OpcodeStore.h" + +#include "ClientStore.h" +#include "ServerStore.h" + +#include "ClientCache.h" +#include "ServerCache.h" + +#include "EncodeBuffer.h" +#include "DecodeBuffer.h" + +// +// Forward declaration of referenced classes. +// + +class List; + +class StaticCompressor; + +// +// Set the verbosity level. +// + +#define PANIC +#define WARNING +#undef TEST +#undef DEBUG + +// +// Define this to log a line when a channel +// is created or destroyed. +// + +#undef REFERENCES + +// +// Type of traffic carried by channel. +// + +typedef enum +{ + channel_none = -1, + channel_x11, + channel_cups, + channel_smb, + channel_media, + channel_http, + channel_font, + channel_slave, + channel_last_tag + +} T_channel_type; + +// +// Type of notification event to be sent +// by proxy to the X channel. +// + +typedef enum +{ + notify_no_split, + notify_start_split, + notify_commit_split, + notify_end_split, + notify_empty_split, + +} T_notification_type; + +class Channel +{ + public: + + // + // Maximum number of X connections supported. + // + + static const int CONNECTIONS_LIMIT = 256; + + Channel(Transport *transport, StaticCompressor *compressor); + + virtual ~Channel(); + + // + // Read any X message available on the X + // connection and encode it to the encode + // buffer. + // + + virtual int handleRead(EncodeBuffer &encodeBuffer, const unsigned char *message, + unsigned int length) = 0; + + // + // Decode any X message encoded in the + // proxy message and write it to the X + // connection. + // + + virtual int handleWrite(const unsigned char *message, unsigned int length) = 0; + + // + // Other methods to be implemented in + // client, server and generic channel + // classes. + // + + virtual int handleSplit(EncodeBuffer &encodeBuffer, MessageStore *store, + T_store_action action, int position, const unsigned char opcode, + const unsigned char *buffer, const unsigned int size) = 0; + + virtual int handleSplit(DecodeBuffer &decodeBuffer, MessageStore *store, + T_store_action action, int position, unsigned char &opcode, + unsigned char *&buffer, unsigned int &size) = 0; + + virtual int handleSplit(EncodeBuffer &encodeBuffer) = 0; + + virtual int handleSplit(DecodeBuffer &decodeBuffer) = 0; + + virtual int handleSplitEvent(EncodeBuffer &encodeBuffer, Split *split) = 0; + + virtual int handleSplitEvent(DecodeBuffer &decodeBuffer) = 0; + + virtual int handleMotion(EncodeBuffer &encodeBuffer) = 0; + + virtual int handleCompletion(EncodeBuffer &encodeBuffer) = 0; + + virtual int handleConfiguration() = 0; + + virtual int handleFinish() = 0; + + // + // Interleave reads of the available + // events while writing data to the + // channel socket. + // + + virtual int handleAsyncEvents() = 0; + + // + // Handle the channel tear down. + // + + int handleClosing() + { + closing_ = 1; + + return 1; + } + + int handleDrop() + { + drop_ = 1; + + return 1; + } + + // + // Try to read more data from the socket. In + // the meanwhile flush any enqueued data if + // the channel is blocked. Return as soon as + // more data has been read or the timeout has + // been exceeded. + // + + int handleWait(int timeout); + + // + // Drain the output buffer while handling the + // data that may become readable. + // + + int handleDrain(int timeout, int limit); + + // + // Flush any remaining data in the transport + // buffer. + // + + int handleFlush(); + + // + // Called when the loop has replaced or + // closed a previous alert. + // + + void handleResetAlert(); + + // + // Initialize all the static members. + // + + static int setReferences(); + + // + // Set pointer to object mapping opcodes + // of NX specific messages. + // + + int setOpcodes(OpcodeStore *opcodeStore); + + // + // Update pointers to message stores in + // channels. + // + + int setStores(ClientStore *clientStore, ServerStore *serverStore); + + // + // The same for channels caches. + // + + int setCaches(ClientCache *clientCache, ServerCache *serverCache); + + // + // Set the port used for tunneling of the + // font server connections. + // + + void setPorts(int fontPort) + { + fontPort_ = fontPort; + } + + // + // Check if there are pending split + // to send to the remote side. + // + + virtual int needSplit() const = 0; + + // + // Check if there are motion events + // to flush. + // + + virtual int needMotion() const = 0; + + // + // Return the type of traffic carried + // by this channel. + // + + virtual T_channel_type getType() const = 0; + + // + // Check if the channel has been marked + // as closing down. + // + + int getFinish() const + { + return finish_; + } + + int getClosing() + { + return closing_; + } + + int getDrop() + { + return drop_; + } + + int getCongestion() + { + return congestion_; + } + + protected: + + int handleFlush(T_flush type) + { + // + // We could write the data immediately if there + // is already something queued to the low level + // TCP buffers. + // + // if (... || transport_ -> queued() > 0) + // { + // ... + // } + // + + if (writeBuffer_.getScratchLength() > 0 || + (type == flush_if_any && writeBuffer_.getLength() > 0) || + writeBuffer_.getLength() >= (unsigned int) + control -> TransportFlushBufferSize) + { + return handleFlush(type, writeBuffer_.getLength(), + writeBuffer_.getScratchLength()); + } + + return 0; + } + + // + // Actually flush the data to the + // channel descriptor. + // + + int handleFlush(T_flush type, int bufferLength, int scratchLength); + + // + // Handle the congestion changes. + // + + int handleCongestion(); + + // + // Encode and decode X messages. + // + + int handleEncode(EncodeBuffer &encodeBuffer, ChannelCache *channelCache, + MessageStore *store, const unsigned char opcode, + const unsigned char *buffer, const unsigned int size); + + int handleDecode(DecodeBuffer &decodeBuffer, ChannelCache *channelCache, + MessageStore *store, unsigned char &opcode, + unsigned char *&buffer, unsigned int &size); + + // + // Encode the message based on its + // message store. + // + + int handleEncodeCached(EncodeBuffer &encodeBuffer, ChannelCache *channelCache, + MessageStore *store, const unsigned char *buffer, + const unsigned int size); + + int handleDecodeCached(DecodeBuffer &decodeBuffer, ChannelCache *channelCache, + MessageStore *store, unsigned char *&buffer, + unsigned int &size); + + int handleEncodeIdentity(EncodeBuffer &encodeBuffer, ChannelCache *channelCache, + MessageStore *store, const unsigned char *buffer, + const unsigned int size, int bigEndian) + { + return (store -> encodeIdentity(encodeBuffer, buffer, size, + bigEndian, channelCache)); + } + + int handleDecodeIdentity(DecodeBuffer &decodeBuffer, ChannelCache *channelCache, + MessageStore *store, unsigned char *&buffer, + unsigned int &size, int bigEndian, + WriteBuffer *writeBuffer) + { + return (store -> decodeIdentity(decodeBuffer, buffer, size, bigEndian, + writeBuffer, channelCache)); + } + + // + // Other utility functions used by + // the encoding and decoding methods. + // + + void handleCopy(EncodeBuffer &encodeBuffer, const unsigned char opcode, + const unsigned int offset, const unsigned char *buffer, + const unsigned int size) + { + if (size > offset) + { + encodeBuffer.encodeMemory(buffer + offset, size - offset); + } + } + + void handleCopy(DecodeBuffer &decodeBuffer, const unsigned char opcode, + const unsigned int offset, unsigned char *buffer, + const unsigned int size) + { + if (size > offset) + { + memcpy(buffer + offset, decodeBuffer.decodeMemory(size - offset), size - offset); + } + } + + void handleUpdate(MessageStore *store, const unsigned int dataSize, + const unsigned int compressedDataSize) + { + if (store -> lastAction == IS_ADDED) + { + handleUpdateAdded(store, dataSize, compressedDataSize); + } + } + + void handleSave(MessageStore *store, unsigned char *buffer, unsigned int size, + const unsigned char *compressedData = NULL, + const unsigned int compressedDataSize = 0) + { + if (store -> lastAction == IS_ADDED) + { + handleSaveAdded(store, 0, buffer, size, compressedData, compressedDataSize); + } + } + + void handleSaveSplit(MessageStore *store, unsigned char *buffer, + unsigned int size) + { + if (store -> lastAction == IS_ADDED) + { + return handleSaveAdded(store, 1, buffer, size, 0, 0); + } + } + + void handleUpdateAdded(MessageStore *store, const unsigned int dataSize, + const unsigned int compressedDataSize); + + void handleSaveAdded(MessageStore *store, int split, unsigned char *buffer, + unsigned int size, const unsigned char *compressedData, + const unsigned int compressedDataSize); + + // + // Compress the data part of a message + // using ZLIB or another compressor + // and send it over the network. + // + + int handleCompress(EncodeBuffer &encodeBuffer, const unsigned char opcode, + const unsigned int offset, const unsigned char *buffer, + const unsigned int size, unsigned char *&compressedData, + unsigned int &compressedDataSize); + + int handleDecompress(DecodeBuffer &decodeBuffer, const unsigned char opcode, + const unsigned int offset, unsigned char *buffer, + const unsigned int size, const unsigned char *&compressedData, + unsigned int &compressedDataSize); + + // + // Send an X_NoOperation to the X server. + // The second version also removes any + // previous data in the write buffer. + // + + int handleNullRequest(unsigned char &opcode, unsigned char *&buffer, + unsigned int &size); + + int handleCleanAndNullRequest(unsigned char &opcode, unsigned char *&buffer, + unsigned int &size); + + // + // X11 channels are considered to be in + // congestion state when there was a + // blocking write and, since then, the + // local end didn't consume all the data. + // + + virtual int isCongested() + { + return (transport_ -> getType() != + transport_agent && transport_ -> length() > + control -> TransportFlushBufferSize); + } + + virtual int isReliable() + { + return 1; + } + + // + // Determine how to handle allocation + // of new messages in the message + // stores. + // + + int mustCleanStore(MessageStore *store) + { + return (store -> getRemoteTotalStorageSize() > control -> + RemoteTotalStorageSize || store -> getLocalTotalStorageSize() > + control -> LocalTotalStorageSize || (store -> getRemoteStorageSize() > + (control -> RemoteTotalStorageSize / 100 * store -> + cacheThreshold)) || (store -> getLocalStorageSize() > + (control -> LocalTotalStorageSize / 100 * store -> + cacheThreshold))); + } + + int canCleanStore(MessageStore *store) + { + return ((store -> getSize() > 0 && (store -> getRemoteStorageSize() > + (control -> RemoteTotalStorageSize / 100 * store -> + cacheLowerThreshold))) || (store -> getLocalStorageSize() > + (control -> LocalTotalStorageSize / 100 * store -> + cacheLowerThreshold))); + } + + protected: + + // + // Set up the split stores. + // + + void handleSplitStoreError(int resource); + + void handleSplitStoreAlloc(List *list, int resource); + void handleSplitStoreRemove(List *list, int resource); + + Split *handleSplitCommitRemove(int request, int resource, int position); + + void validateSize(const char *name, int input, int output, + int offset, int size) + { + if (size < offset || size > control -> MaximumMessageSize || + size != (int) RoundUp4(input) + offset || + output > control -> MaximumMessageSize) + { + *logofs << "Channel: PANIC! Invalid size " << size + << " for " << name << " output with data " + << input << "/" << output << "/" << offset + << "/" << size << ".\n" << logofs_flush; + + cerr << "Error" << ": Invalid size " << size + << " for " << name << " output.\n"; + + HandleAbort(); + } + } + + // + // Is the X client big endian? + // + + int bigEndian() const + { + return bigEndian_; + } + + int bigEndian_; + + // + // Other X server's features + // saved at session startup. + // + + unsigned int imageByteOrder_; + unsigned int bitmapBitOrder_; + unsigned int scanlineUnit_; + unsigned int scanlinePad_; + + int firstRequest_; + int firstReply_; + + // + // Use this class for IO operations. + // + + Transport *transport_; + + // + // The static compressor is created by the + // proxy and shared among channels. + // + + StaticCompressor *compressor_; + + // + // Map NX operations to opcodes. Propagated + // by proxy to all channels on the same X + // server. + // + + OpcodeStore *opcodeStore_; + + // + // Also stores are shared between channels. + // + + ClientStore *clientStore_; + ServerStore *serverStore_; + + // + // Caches are specific for each channel. + // + + ClientCache *clientCache_; + ServerCache *serverCache_; + + // + // Data going to X connection. + // + + WriteBuffer writeBuffer_; + + // + // Other data members. + // + + int fd_; + + int finish_; + int closing_; + int drop_; + int congestion_; + int priority_; + + int alert_; + + // + // It will be set to the descriptor of the + // first X channel that is successfully con- + // nected and will print an info message on + // standard error. + // + + static int firstClient_; + + // + // Port used for font server connections. + // + + static int fontPort_; + + // + // Track which cache operations have been + // enabled by the agent. + // + + int enableCache_; + int enableSplit_; + int enableSave_; + int enableLoad_; + + // + // Keep track of object creation and + // deletion. + // + + #ifdef REFERENCES + + static int references_; + + #endif +}; + +#endif /* Channel_H */ |