Merge branch 'nxcomp'

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 */