File indexing completed on 2025-03-16 08:11:25

 /*
     This file is part of Konsole, an X terminal.
     SPDX-FileCopyrightText: 1997, 1998 Lars Doelle <lars.doelle@on-line.de>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
 
     You should have received a copy of the GNU General Public License
     along with this program; if not, write to the Free Software
     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
     02110-1301  USA.
 */
 
 #ifndef TEHISTORY_H
 #define TEHISTORY_H
 
 // Qt
 #include <QBitRef>
 #include <QHash>
 #include <QTemporaryFile>
 #include <QVector>
 
 // KDE
 // #include <ktemporaryfile.h>
 
 // Konsole
 #include "BlockArray.h"
 #include "Character.h"
 
 // map
 #include <memory>
 #include <sys/mman.h>
 
 namespace Konsole
 {
 
 #if 1
 /*
    An extendable tmpfile(1) based buffer.
 */
 
 class HistoryFile
 {
 public:
     HistoryFile();
     virtual ~HistoryFile();
 
     virtual void add(const unsigned char *bytes, int len);
     virtual void get(unsigned char *bytes, int len, int loc);
     virtual int len();
 
     // mmaps the file in read-only mode
     void map();
     // un-mmaps the file
     void unmap();
     // returns true if the file is mmap'ed
     bool isMapped() const;
 
 private:
     int ion;
     int length;
     QTemporaryFile tmpFile;
 
     // pointer to start of mmap'ed file data, or 0 if the file is not mmap'ed
     char *fileMap;
 
     // incremented whenver 'add' is called and decremented whenever
     //'get' is called.
     // this is used to detect when a large number of lines are being read and processed from the history
     // and automatically mmap the file for better performance (saves the overhead of many lseek-read calls).
     int readWriteBalance;
 
     // when readWriteBalance goes below this threshold, the file will be mmap'ed automatically
     static const int MAP_THRESHOLD = -1000;
 };
 #endif
 
 //////////////////////////////////////////////////////////////////////
 
 //////////////////////////////////////////////////////////////////////
 // Abstract base class for file and buffer versions
 //////////////////////////////////////////////////////////////////////
 class HistoryType;
 
 class HistoryScroll
 {
 public:
     HistoryScroll(HistoryType *);
     virtual ~HistoryScroll();
 
     virtual bool hasScroll();
 
     // access to history
     virtual int getLines() = 0;
     virtual int getLineLen(int lineno) = 0;
     virtual void getCells(int lineno, int colno, int count, std::span<Character> res) = 0;
     virtual bool isWrappedLine(int lineno) = 0;
 
     // backward compatibility (obsolete)
     Character getCell(int lineno, int colno)
     {
         Character res;
         getCells(lineno, colno, 1, std::span(&res, 1));
         return res;
     }
 
     // adding lines.
     virtual void addCells(std::span<const Character> a, int count) = 0;
     // convenience method - this is virtual so that subclasses can take advantage
     // of QVector's implicit copying
     virtual void addCellsVector(const QVector<Character> &cells)
     {
         auto span = std::span<const Character>{cells.data(), size_t(cells.size())};
         addCells(span, cells.size());
     }
 
     virtual void addLine(bool previousWrapped = false) = 0;
 
     //
     // FIXME:  Passing around constant references to HistoryType instances
     // is very unsafe, because those references will no longer
     // be valid if the history scroll is deleted.
     //
     const HistoryType &getType()
     {
         return *m_histType;
     }
 
 protected:
     HistoryType *m_histType;
 };
 
 #if 1
 
 //////////////////////////////////////////////////////////////////////
 // File-based history (e.g. file log, no limitation in length)
 //////////////////////////////////////////////////////////////////////
 
 class HistoryScrollFile : public HistoryScroll
 {
 public:
     HistoryScrollFile(const QString &logFileName);
     ~HistoryScrollFile() override;
 
     int getLines() override;
     int getLineLen(int lineno) override;
     void getCells(int lineno, int colno, int count, std::span<Character> res) override;
     bool isWrappedLine(int lineno) override;
 
     void addCells(std::span<const Character> a, int count) override;
     void addLine(bool previousWrapped = false) override;
 
 private:
     int startOfLine(int lineno);
 
     QString m_logFileName;
     HistoryFile index; // lines Row(int)
     HistoryFile cells; // text  Row(Character)
     HistoryFile lineflags; // flags Row(unsigned char)
 };
 
 //////////////////////////////////////////////////////////////////////
 // Buffer-based history (limited to a fixed nb of lines)
 //////////////////////////////////////////////////////////////////////
 class HistoryScrollBuffer : public HistoryScroll
 {
 public:
     typedef QVector<Character> HistoryLine;
 
     HistoryScrollBuffer(unsigned int maxNbLines = 1000);
     ~HistoryScrollBuffer() override;
 
     int getLines() override;
     int getLineLen(int lineno) override;
     void getCells(int lineno, int colno, int count, std::span<Character> res) override;
     bool isWrappedLine(int lineno) override;
 
     void addCells(std::span<const Character> a, int count) override;
     void addCellsVector(const QVector<Character> &cells) override;
     void addLine(bool previousWrapped = false) override;
 
     void setMaxNbLines(unsigned int nbLines);
     unsigned int maxNbLines() const
     {
         return _maxLineCount;
     }
 
 private:
     int bufferIndex(int lineNumber) const;
 
     HistoryLine *_historyBuffer;
     QBitArray _wrappedLine;
     int _maxLineCount;
     int _usedLines;
     int _head;
 
     // QVector<histline*> m_histBuffer;
     // QBitArray m_wrappedLine;
     // unsigned int m_maxNbLines;
     // unsigned int m_nbLines;
     // unsigned int m_arrayIndex;
     // bool         m_buffFilled;
 };
 
 /*class HistoryScrollBufferV2 : public HistoryScroll
 {
 public:
   virtual int  getLines();
   virtual int  getLineLen(int lineno);
   virtual void getCells(int lineno, int colno, int count, Character res[]);
   virtual bool isWrappedLine(int lineno);
 
   virtual void addCells(const Character a[], int count);
   virtual void addCells(const QVector<Character>& cells);
   virtual void addLine(bool previousWrapped=false);
 
 };*/
 
 #endif
 
 //////////////////////////////////////////////////////////////////////
 // Nothing-based history (no history :-)
 //////////////////////////////////////////////////////////////////////
 class HistoryScrollNone : public HistoryScroll
 {
 public:
     HistoryScrollNone();
     ~HistoryScrollNone() override;
 
     bool hasScroll() override;
 
     int getLines() override;
     int getLineLen(int lineno) override;
     void getCells(int lineno, int colno, int count, std::span<Character> res) override;
     bool isWrappedLine(int lineno) override;
 
     void addCells(std::span<const Character> a, int count) override;
     void addLine(bool previousWrapped = false) override;
 };
 
 //////////////////////////////////////////////////////////////////////
 // BlockArray-based history
 //////////////////////////////////////////////////////////////////////
 class HistoryScrollBlockArray : public HistoryScroll
 {
 public:
     HistoryScrollBlockArray(size_t size);
     ~HistoryScrollBlockArray() override;
 
     int getLines() override;
     int getLineLen(int lineno) override;
     void getCells(int lineno, int colno, int count, std::span<Character> res) override;
     bool isWrappedLine(int lineno) override;
 
     void addCells(std::span<const Character> a, int count) override;
     void addLine(bool previousWrapped = false) override;
 
 protected:
     BlockArray m_blockArray;
     QHash<int, size_t> m_lineLengths;
 };
 
 //////////////////////////////////////////////////////////////////////
 // History using compact storage
 // This implementation uses a list of fixed-sized blocks
 // where history lines are allocated in (avoids heap fragmentation)
 //////////////////////////////////////////////////////////////////////
 typedef QVector<Character> TextLine;
 
 class CharacterFormat
 {
 public:
     bool equalsFormat(const CharacterFormat &other) const
     {
         return other.rendition == rendition && other.fgColor == fgColor && other.bgColor == bgColor;
     }
 
     bool equalsFormat(const Character &c) const
     {
         return c.rendition == rendition && c.foregroundColor == fgColor && c.backgroundColor == bgColor;
     }
 
     void setFormat(const Character &c)
     {
         rendition = c.rendition;
         fgColor = c.foregroundColor;
         bgColor = c.backgroundColor;
     }
 
     CharacterColor fgColor, bgColor;
     quint16 startPos;
     quint8 rendition;
 };
 
 class CompactHistoryBlock
 {
 public:
     CompactHistoryBlock()
     {
         blockLength = 4096 * 64; // 256kb
         head = (quint8 *)mmap(nullptr, blockLength, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
         // head = (quint8*) malloc(blockLength);
         Q_ASSERT(head != MAP_FAILED);
         tail = blockStart = head;
         allocCount = 0;
     }
 
     virtual ~CompactHistoryBlock()
     {
         // free(blockStart);
         munmap(blockStart, blockLength);
     }
 
     virtual unsigned int remaining()
     {
         return blockStart + blockLength - tail;
     }
     virtual unsigned length()
     {
         return blockLength;
     }
     virtual void *allocate(size_t length);
     virtual bool contains(void *addr)
     {
         return addr >= blockStart && addr < (blockStart + blockLength);
     }
     virtual void deallocate();
     virtual bool isInUse()
     {
         return allocCount != 0;
     };
 
 private:
     size_t blockLength;
     quint8 *head;
     quint8 *tail;
     quint8 *blockStart;
     int allocCount;
 };
 
 class CompactHistoryBlockList
 {
 public:
     CompactHistoryBlockList(){};
     ~CompactHistoryBlockList();
 
     void *allocate(size_t size);
     void deallocate(void *);
     int length()
     {
         return list.size();
     }
 
 private:
     QList<CompactHistoryBlock *> list;
 };
 
 class CompactHistoryLine
 {
 public:
     CompactHistoryLine(const TextLine &, CompactHistoryBlockList &blockList);
     virtual ~CompactHistoryLine();
 
     // custom new operator to allocate memory from custom pool instead of heap
     static void *operator new(size_t size, CompactHistoryBlockList &blockList);
     static void operator delete(void *){/* do nothing, deallocation from pool is done in destructor*/};
 
     virtual void getCharacters(Character *array, int length, int startColumn);
     virtual void getCharacter(int index, Character &r);
     virtual bool isWrapped() const
     {
         return wrapped;
     };
     virtual void setWrapped(bool isWrapped)
     {
         wrapped = isWrapped;
     };
     virtual unsigned int getLength() const
     {
         return length;
     };
 
 protected:
     CompactHistoryBlockList &blockList;
     CharacterFormat *formatArray;
     quint16 length;
     quint16 *text;
     quint16 formatLength;
     bool wrapped;
 };
 
 class CompactHistoryScroll : public HistoryScroll
 {
     typedef QList<CompactHistoryLine *> HistoryArray;
 
 public:
     CompactHistoryScroll(unsigned int maxNbLines = 1000);
     ~CompactHistoryScroll() override;
 
     int getLines() override;
     int getLineLen(int lineno) override;
     void getCells(int lineno, int colno, int count, std::span<Character> res) override;
     bool isWrappedLine(int lineno) override;
 
     void addCells(std::span<const Character> a, int count) override;
     void addCellsVector(const TextLine &cells) override;
     void addLine(bool previousWrapped = false) override;
 
     void setMaxNbLines(unsigned int nbLines);
     unsigned int maxNbLines() const
     {
         return _maxLineCount;
     }
 
 private:
     bool hasDifferentColors(const TextLine &line) const;
     HistoryArray lines;
     CompactHistoryBlockList blockList;
 
     unsigned int _maxLineCount;
 };
 
 //////////////////////////////////////////////////////////////////////
 // History type
 //////////////////////////////////////////////////////////////////////
 
 class HistoryType
 {
 public:
     HistoryType();
     virtual ~HistoryType();
 
     /**
      * Returns true if the history is enabled ( can store lines of output )
      * or false otherwise.
      */
     virtual bool isEnabled() const = 0;
     /**
      * Returns true if the history size is unlimited.
      */
     bool isUnlimited() const
     {
         return maximumLineCount() == 0;
     }
     /**
      * Returns the maximum number of lines which this history type
      * can store or 0 if the history can store an unlimited number of lines.
      */
     virtual int maximumLineCount() const = 0;
 
     virtual std::unique_ptr<HistoryScroll> scroll(std::unique_ptr<HistoryScroll> &&) const = 0;
 };
 
 class HistoryTypeNone : public HistoryType
 {
 public:
     HistoryTypeNone();
 
     bool isEnabled() const override;
     int maximumLineCount() const override;
 
     std::unique_ptr<HistoryScroll> scroll(std::unique_ptr<HistoryScroll> &&) const override;
 };
 
 class HistoryTypeBlockArray : public HistoryType
 {
 public:
     HistoryTypeBlockArray(size_t size);
 
     bool isEnabled() const override;
     int maximumLineCount() const override;
 
     std::unique_ptr<HistoryScroll> scroll(std::unique_ptr<HistoryScroll> &&) const override;
 
 protected:
     size_t m_size;
 };
 
 #if 1
 class HistoryTypeFile : public HistoryType
 {
 public:
     HistoryTypeFile(const QString &fileName = QString());
 
     bool isEnabled() const override;
     virtual const QString &getFileName() const;
     int maximumLineCount() const override;
 
     std::unique_ptr<HistoryScroll> scroll(std::unique_ptr<HistoryScroll> &&) const override;
 
 protected:
     QString m_fileName;
 };
 
 class HistoryTypeBuffer : public HistoryType
 {
     friend class HistoryScrollBuffer;
 
 public:
     HistoryTypeBuffer(unsigned int nbLines);
 
     bool isEnabled() const override;
     int maximumLineCount() const override;
 
     std::unique_ptr<HistoryScroll> scroll(std::unique_ptr<HistoryScroll> &&) const override;
 
 protected:
     unsigned int m_nbLines;
 };
 
 class CompactHistoryType : public HistoryType
 {
 public:
     CompactHistoryType(unsigned int size);
 
     bool isEnabled() const override;
     int maximumLineCount() const override;
 
     std::unique_ptr<HistoryScroll> scroll(std::unique_ptr<HistoryScroll> &&) const override;
 
 protected:
     unsigned int m_nbLines;
 };
 
 #endif
 
 }
 
 #endif // TEHISTORY_H