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 SETUP_COMPRESS_BZ_H
  17 #define SETUP_COMPRESS_BZ_H
  18
  19 #include "compress.h"
  20
  21 #include <bzlib.h>
  22
  23 class compress_bz:public compress
  24 {
  25 public:
  26   /* assumes decompression */
  27   compress_bz (io_stream *);
  28   /* allows comp/decomp but this implementation only handles comp */
  29   compress_bz (io_stream *, const char *);
  30   /* read data (duh!) */
  31   virtual ssize_t read (void *buffer, size_t len);
  32   /* provide data to (double duh!) */
  33   virtual ssize_t write (const void *buffer, size_t len);
  34   /* read data without removing it from the class's internal buffer */
  35   virtual ssize_t peek (void *buffer, size_t len);
  36   virtual off_t tell ();
  37   virtual off_t seek (off_t where, io_stream_seek_t whence);
  38   /* try guessing this one */
  39   virtual int error ();
  40   /* Find out the next stream name -
  41    * ie for foo.tar.bz, at offset 0, next_file_name = foo.tar
  42    * for foobar that is an compress, next_file_name is the next
  43    * extractable filename.
  44    */
  45   virtual const char *next_file_name ()
  46   {
  47     return NULL;
  48   };
  49   virtual int set_mtime (time_t);
  50   /* Use seek EOF, then tell (). get_size won't do this incase you are sucking dow
  51       * over a WAN :} */
  52   virtual size_t get_size () {return 0;};
  53   virtual time_t get_mtime ();
  54   virtual mode_t get_mode ();
  55   virtual void release_original (); /* give up ownership of original io_stream */
  56   /* if you are still needing these hints... give up now! */
  57     virtual ~ compress_bz ();
  58 private:
  59   io_stream *original;
  60   bool owns_original;
  61   char peekbuf[512];
  62   size_t peeklen;
  63   int lasterr;
  64   bz_stream strm;
  65   int initialisedOk;
  66   int endReached;
  67   char buf[4096];
  68   int writing;
  69   size_t position;
  70   void init_state(void);
  71 };
  72
  73 #endif /* SETUP_COMPRESS_BZ_H */