Java example source code file (filebuff.hpp)

This example Java source code file (filebuff.hpp) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

archdesc, architecture, bufferedfile, description, destructor, expected, filebuff, filebuffregion, merge, null, share_vm_adlc_filebuff_hpp, start, the, workaround

The filebuff.hpp Java example source code

/*
 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#ifndef SHARE_VM_ADLC_FILEBUFF_HPP
#define SHARE_VM_ADLC_FILEBUFF_HPP

// FILEBUFF.HPP - Definitions for parser file buffering routines
#include <iostream>

using namespace std;

// STRUCTURE FOR HANDLING INPUT AND OUTPUT FILES

class BufferedFile {
 public:
  const char *_name;
  FILE *_fp;
  inline BufferedFile() { _name = NULL; _fp = NULL; };
  inline ~BufferedFile() {};
};

class ArchDesc;

//------------------------------FileBuff--------------------------------------
// This class defines a nicely behaved buffer of text.  Entire file of text
// is read into buffer at creation, with sentinels at start and end.
class FileBuff {
  friend class FileBuffRegion;
 private:
  long  _bufferSize;            // Size of text holding buffer.
  long  _offset;                // Expected filepointer offset.
  long  _bufoff;                // Start of buffer file offset

  char *_buf;                   // The buffer itself.
  char *_bigbuf;                // The buffer plus sentinels; actual heap area
  char *_bufmax;                // A pointer to the buffer end sentinel
  char *_bufeol;                // A pointer to the last complete line end

  int   _err;                   // Error flag for file seek/read operations
  long  _filepos;               // Current offset from start of file
  int   _linenum;

  ArchDesc& _AD;                // Reference to Architecture Description

  // Error reporting function
  void file_error(int flag, int linenum, const char *fmt, ...);

 public:
  const BufferedFile *_fp;           // File to be buffered

  FileBuff(BufferedFile *fp, ArchDesc& archDesc); // Constructor
  ~FileBuff();                  // Destructor

  // This returns a pointer to the start of the current line in the buffer,
  // and increments bufeol and filepos to point at the end of that line.
  char *get_line(void);
  int linenum() const { return _linenum; }
  void set_linenum(int line) { _linenum = line; }

  // This converts a pointer into the buffer to a file offset.  It only works
  // when the pointer is valid (i.e. just obtained from getline()).
  long getoff(const char* s) { return _bufoff + (long)(s - _buf); }
};

//------------------------------FileBuffRegion---------------------------------
// A buffer region is really a region of some file, specified as a linked list
// of offsets and lengths.  These regions can be merged; overlapping regions
// will coalesce.
class FileBuffRegion {
 public:                        // Workaround dev-studio friend/private bug
  FileBuffRegion *_next;        // Linked list of regions sorted by offset.
 private:
  FileBuff       *_bfr;         // The Buffer of the file
  int _offset, _length;         // The file area
  int             _sol;         // Start of line where the file area starts
  int             _line;        // First line of region

 public:
  FileBuffRegion(FileBuff*, int sol, int line, int offset, int len);
  ~FileBuffRegion();

  FileBuffRegion *copy();                   // Deep copy
  FileBuffRegion *merge(FileBuffRegion*); // Merge 2 regions; delete input

  void print(ostream&);
  friend ostream& operator<< (ostream&, FileBuffRegion&);
};

#endif // SHARE_VM_ADLC_FILEBUFF_HPP