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+/**************************************************************************/
+/* */
+/* 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 IntCache_H
+#define IntCache_H
+
+class IntCache
+{
+ public:
+
+ IntCache(unsigned int size);
+
+ ~IntCache()
+ {
+ delete [] buffer_;
+ }
+
+ unsigned int getSize() const
+ {
+ return length_;
+ }
+
+ int lookup(unsigned int &value, unsigned int &index,
+ unsigned int mask, unsigned int &sameDiff);
+
+ //
+ // This can be inlined as it is only
+ // called by decodeCachedValue().
+ //
+
+ unsigned int get(unsigned int index)
+ {
+ unsigned int result = buffer_[index];
+
+ if (index != 0)
+ {
+ //
+ // Using a memmove() appears to be slower.
+ //
+ // unsigned int target = index >> 1;
+ //
+ // memmove((char *) &buffer_[target + 1], (char *) &buffer_[target],
+ // sizeof(unsigned int) * (index - target));
+ //
+ // buffer_[target] = result;
+ //
+
+ unsigned int i = index;
+
+ unsigned int target = (i >> 1);
+
+ do
+ {
+ buffer_[i] = buffer_[i - 1];
+
+ i--;
+ }
+ while (i > target);
+
+ buffer_[target] = result;
+ }
+
+ return result;
+ }
+
+ void insert(unsigned int &value, unsigned int mask);
+
+ void push(unsigned int &value, unsigned int mask);
+
+ void dump();
+
+ unsigned int getLastDiff(unsigned int mask) const
+ {
+ return lastDiff_;
+ }
+
+ unsigned int getBlockSize(unsigned int bits) const
+ {
+ if (bits > 0)
+ {
+ return (predictedBlockSize_ < bits ? predictedBlockSize_ : bits);
+ }
+
+ return predictedBlockSize_;
+ }
+
+ private:
+
+ unsigned int size_;
+ unsigned int length_;
+ unsigned int *buffer_;
+ unsigned int lastDiff_;
+ unsigned int lastValueInserted_;
+ unsigned int predictedBlockSize_;
+};
+
+#endif /* IntCache_H */