"Israel Fdez. Cabrera" <israel@segurmatica.com> wrote in message news:416DA364.2070107@segurmatica.com...
Jonathan Turkanis wrote:
The library needs to be cleaned up a lot before I can post it. If there is sufficient interest, I'll try to do it, but it would be at least a couple months from now, since I'll be busy trying to get iostreams ready for 1.33.
There is interest in the library, and I'm sure some other have interest too. iostream is a great step ahead in C++, but with this kind of support for compressed, OLE files and maybe more, it will be just fantastic. It is fantastic to compress and decompress file in just 6 lines of code dont you think? :)
Yes, but I'm aiming for 4. ;-)
Let's think I have to use other library, i.e. libgsf from GNU. I have the following doubt. I have a single OLE file, I open() it using a boost::io stream, how more than one stream can be obtained from a single one, taking this OLE file has more than one contained file?
For each type of archive (zip, tar, ole) you have to have a module (an 'archive_handler') that knows the format and can extract the information. The appropriate handler is called automatically when someone wants to read an entry for an archive of a particular type. To implement a handler, however, you need to write code which either completely understands the file format in question or delegates that responsibility to an outside library. For OLE compound documents on a windows system, this is simple, since you just use the functions StgOpenStorageEx, IStorage::EnumElements, etc. On Linux, you either have to implement everything yourself, or rely on an existing library. I would assume that such libraries exist. There are also licensing issues to consider. But again, I don't know much about that.
The same reasoning could be applied to compressed files. How to extract more than one compressed file using Iostream.
The zip and tar formats are well-documented and it should be easy to write handlers for them. Let me repeat, though, that this is a separate project, not within the scope of the current library.
Israel
Jonathan