compress_bz.h

   1 /*
   2  * Copyright (c) 2001, Robert Collins.
   3  *
   4  *     This program is free software; you can redistribute it and/or modify
   5  *     it under the terms of the GNU General Public License as published by
   6  *     the Free Software Foundation; either version 2 of the License, or
   7  *     (at your option) any later version.
   8  *
   9  *     A copy of the GNU General Public License can be found at
  10  *     http://www.gnu.org/
  11  *
  12  * Written by Robert Collins  <rbtcollins@hotmail.com>
  13  *
  14  */
  15
  16 #ifndef _COMPRESS_BZ_H_
  17 #define _COMPRESS_BZ_H_
  18
  19 /* this is the bz2 class for all compressed IO operations.
  20  */
  21
  22 #ifdef _WIN32
  23 #undef _WIN32
  24 #include <bzlib.h>
  25 #define _WIN32
  26 #else
  27 #include <bzlib.h>
  28 #endif
  29
  30 class compress_bz:public compress
  31 {
  32 public:
  33   /* assumes decompression */
  34   compress_bz (io_stream *);
  35   /* allows comp/decomp but this implementation only handles comp */
  36   compress_bz (io_stream *, const char *);
  37   /* read data (duh!) */
  38   virtual ssize_t read (void *buffer, size_t len);
  39   /* provide data to (double duh!) */
  40   virtual ssize_t write (const void *buffer, size_t len);
  41   /* read data without removing it from the class's internal buffer */
  42   virtual ssize_t peek (void *buffer, size_t len);
  43   virtual long tell ();
  44   virtual int seek (long where, io_stream_seek_t whence);
  45   /* try guessing this one */
  46   virtual int error ();
  47   /* Find out the next stream name -
  48    * ie for foo.tar.bz, at offset 0, next_file_name = foo.tar
  49    * for foobar that is an compress, next_file_name is the next
  50    * extractable filename.
  51    */
  52   virtual const char *next_file_name ()
  53   {
  54     return NULL;
  55   };
  56   virtual int set_mtime (int);
  57   /* Use seek EOF, then tell (). get_size won't do this incase you are sucking dow
  58       * over a WAN :} */
  59   virtual size_t get_size () {return 0;};
  60   virtual int get_mtime ();
  61   /* if you are still needing these hints... give up now! */
  62     virtual ~ compress_bz ();
  63 private:
  64   io_stream *original;
  65   char peekbuf[512];
  66   size_t peeklen;
  67   int lasterr;
  68   bz_stream strm;
  69   int initialisedOk;
  70   int bufN;
  71   char buf[4096];
  72   int writing;
  73
  74 };
  75
  76 #endif /* _COMPRESS_BZ_H_ */