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Diffstat (limited to 'nxcomp/src/CharCache.h')
| -rw-r--r-- | nxcomp/src/CharCache.h | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/nxcomp/src/CharCache.h b/nxcomp/src/CharCache.h new file mode 100644 index 000000000..b8891d2df --- /dev/null +++ b/nxcomp/src/CharCache.h @@ -0,0 +1,91 @@ +/**************************************************************************/ +/* */ +/* 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 CharCache_H +#define CharCache_H + +// +// CharCache is a counterpart of IntCache that is +// optimized for use in compressing text composed +// of 8-bit characters. +// + +class CharCache +{ + public: + + CharCache() : length_(0) + { + } + + ~CharCache() + { + } + + unsigned int getSize() const + { + return (unsigned int) length_; + } + + int lookup(unsigned char value, unsigned int &index); + + // + // This can be inlined as it is only + // called by decodeCachedValue(). + // + + unsigned int get(unsigned int index) + { + unsigned char result = buffer_[index]; + + if (index != 0) + { + unsigned int i = index; + unsigned int target = (i >> 1); + + do + { + buffer_[i] = buffer_[i - 1]; + + i--; + } + while (i > target); + + buffer_[target] = result; + } + + return (unsigned int) result; + } + + void insert(unsigned char value); + + private: + + unsigned char length_; + + unsigned char buffer_[7]; +}; + +#endif /* CharCache_H */ |