archive.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 _ARCHIVE_H_
  17 #define _ARCHIVE_H_
  18
  19 /* this is the parent class for all archive IO operations.
  20  * It
  21  */
  22
  23 #include "String++.h"
  24
  25 /* The read/write the archive stream to get the archive data is flawed.
  26  * The problem is that you then need a *different* gzip etc class to be able
  27  * to ungzip a gzip from within an archive.
  28  * The correct way is to
  29  * 1) retrieve the file name.
  30  * 2) the user creates their own output object.
  31  * 3) the user calls extract_file (output strea,).
  32  */
  33
  34 typedef enum
  35 {
  36   ARCHIVE_FILE_INVALID,
  37   ARCHIVE_FILE_REGULAR,
  38   ARCHIVE_FILE_HARDLINK,
  39   ARCHIVE_FILE_SYMLINK,
  40   ARCHIVE_FILE_DIRECTORY
  41 }
  42 archive_file_t;
  43
  44
  45 class archive:public io_stream
  46 {
  47 public:
  48   /* get an archive child class from an io_stream */
  49   static archive *extract (io_stream *);
  50   /* get an ouput stream for the next files from the archive.
  51    * returns NULL on failure.
  52    * The stream is not taken over - it will not be automatically deleted
  53    */
  54   virtual io_stream *extract_file () = NULL;
  55   /* extract the next file to the given prefixURL+Path in one step, and name it with the
  56    * given suffix.
  57    * returns 1 on failure.
  58    */
  59   static int extract_file (archive *, String const &, String const &, String const = String());
  60
  61   /*
  62    * To create a stream that will be compressed, you should open the url, and then get a new stream
  63    * from compress::compress.
  64    */
  65   /* read data - not valid for archives (duh!)
  66    * Could be made valid via the read-child-directly model
  67    */
  68 //  virtual ssize_t read(void *buffer, size_t len) {return -1;};
  69   /* provide data to (double duh!) */
  70 //  virtual ssize_t write(void *buffer, size_t len) { return -1;};
  71   /* read data without removing it from the class's internal buffer */
  72 //  virtual ssize_t peek(void *buffer, size_t len);
  73 //  virtual long tell ();
  74   /* try guessing this one */
  75 //  virtual int error ();
  76   /* Find out the next stream name -
  77    * ie for foo.tar.gz, at offset 0, next_file_name = foo.tar
  78    * for foobar that is an compress, next_file_name is the next
  79    * extractable filename.
  80    * The way this works is that when read returns 0, you are at the end of *a* file.
  81    * next_file_name will allow read to be called again, if it returns !NULL
  82    */
  83   virtual String const next_file_name () = NULL;
  84   virtual archive_file_t next_file_type () = ARCHIVE_FILE_INVALID;
  85   virtual String const linktarget () = NULL;
  86   virtual int skip_file () = 0;
  87   /* if you are still needing these hints... give up now! */
  88 //  virtual ~compress ();
  89 protected:
  90   void operator= (const archive &);
  91   archive () {};
  92   archive (const archive &);
  93 private:
  94 //  archive () {};
  95 };
  96
  97 #endif /* _ARCHIVE_H_ */