A lot faster!
BZip2 method supported.
Enhanced Deflate method (64KB slide) supported.

What is Zip-Ada ?

Zip-Ada is a library for dealing with the Zip compressed archive file format. The full sources of Zip-Ada are in Ada, compilable on every compiler and for every system. For more details, read the files zipada.txt and zip.ads from the archive below.
 

Why not call an zip or unzip executable, or use the zlib library ?

• Independence:
  with this library you can zip and unzip data without any OS-dependent external call;
  furthermore, you can use Zip-Ada with any data stream instead of files, for the archives as well as the archived entries.
• Total, unconditional portability:
  • the C code has "only" been widely ported, with specific source parts (via conditional compilation) for different OS and compilers;
  • a single Ada source code set produces a native Zip/UnZip in machine code for every OS, with every Ada compiler (sceptic ? click here to see a list of reportedly successfully tested environments).
• No effort of interfacing, no problem with that.
• Easier to verify and customize.

Download the archive at the SourceForge project page.

• The full library sources inside one directory, Zip_Lib
• ZipAda, a minimal standalone command-line zipping tool - only weak compression available so far
• UnZipAda, a minimal standalone command-line unzipping utility
• Comp_Zip, a command-line utility for comparing two zip files (compare contents, check missing files)
• Find_Zip, a command-line utility for searching a text string across contents of a zip file
• ReZip.adb, a tool for recompressing Zip archives

Tips:
- unzip the archive with its directory structure ("unzip zipada*.zip");
- text-mode and lower case names can be forced for Unix ("unzip -aa -L zipada*.zip").

 
with Zip_Streams;                       use Zip_Streams;
with Zip.Create;                        use Zip.Create;
 
procedure Demo_zip is 
  zip_file : aliased ZipFile_Stream; -- Archive is a file 
  archive : Zip_Create_info;
begin 
  Create (archive, zip_file'Unchecked_Access, "Mini_zip.zip" );
  Add_File(archive, "demo_zip.adb");
  Add_File(archive, "demo_unzip.adb");
  Add_String(archive,
    "==== Hello world! ====" & ASCII.LF &
    "It is such a nice ""Hello world""-like demo, isn't it ?",
    "nice_string.txt"
  );
  Finish (archive);
end Demo_zip;

Browse the source (of version 31)

Source web pages automatically generated by gnathtml (GNAT).

Present state - latest changes (-!- marks an improvement which brings an incompatibility):

• '36', 21-Nov-2009:
  - BZip2 method added for decompression
  - Added Zip.Traverse_verbose
  - Added an UnZip.Extract to extract all files, using a Zip_Info variable
  
• '35', 2-Nov-2009:
  - major performance improvement : decompression 10x faster, compression 3x faster, thanks to a workaround for slow 'Read, 'Write attributes in GNAT & ObjectAda
  - ReZip: HTML display improved
  
• '34', 12-Oct-2009:
  - ReZip: added '-defl' option for having a recompressed archive only with Deflate or Store methods (most compatible)
  - ReZip: added '-comp' option for comparing output against input
  - ReZip: added '-touch' and '-lower' options
  
• '33', 18-Jun-2009:
  - UnZip: added extract_as_text option (cf. UnZipAda with -a option)
  - Zip: Zip_comment function added (cf. UnZipAda with -z option)
  
• '31', 20-Feb-2009:
  - Added tiny demos: Demo_Zip, Demo_UnZip
  -!- Zip.Create: Create / Finish: if Info.Stream is to a file, the underlying archive file is also created / closed as well
  - Added procedure Add_String in Zip.Create
  
• '30', 7-Feb-2009:
  - Added support for the 64KB slide "enhanced deflate" format #9 in UnZip.Decompress
  - Added Find_Zip tool
  - Added Demo_csv_into_zip demo (production of numerous files into a zip archive)
  - LZ77 output in "Reduce" is cached
  
• '29', 30-Jan-2009:
  - Added Zip.LZ77 and Zip.Compress.Reduce
  - Added an ./extra directory with a tiny LZH encoder/decoder
  
• ...
• '26', 30-Aug-2008:
  - zip archive can be any kind of stream (not only a file), for both extraction (unzip) and creation (zip)
• ...
• '22', 14-Dec-2007:
  - Added a new Compose_File_Name to UnZip.File_System_Routines, see new "-d dir" option in the UnZipAda tool
  - Added Zip.Compress, Zip.Compress.Shrink, see the ZipAda tool, which has now the light "Shrink" compression
  
• ...
• '19', 9-Mar-2007:
  - New Zip library with Zip stuff concerning not only decompression; packages: Zip, Zip.Headers, Zip.CRC
• ...
• '11' : 29-Nov-2002:
  New generic procedure for traversing a Zip directory structure.
  As a demo, a tool (comp_zip) for comparing two .Zip archive files. Useful when combining zip, pkzip, 7zip, kzip and zipmix to shrink archives and check them after.
• ...
• '04' : 4-Jul-1999:
  Reduce method debugged. Now all PKZIPs from 1989 to 1999 are supported. File unzipping is finished and works. User information more complete (see unzipada.adb).
  1st publishing in the Public Ada Library.
• ...
• 7-Jun-1999
  Begin of Pascal source translation via P2Ada

Maintainer of Zip-Ada: G. de Montmollin.
For a little sponsoring...  
Visit also the project on SourceForge!  
Technical documentation: read appnote.txt (in the archive).
Legal notice: free distribution copyright (read zip.ads), no warranty.

• Scala
• Stratégies software
• NXP Semiconductors (Philips)
• GLOBE_3D project
• some others are known but undisclosed...

• GNAT Professional (non-free support)
  
• GNAT Public version, free, full sources
  
• ObjectAda (Aonix) Ada95 compiler, with a free version
• HP
• IBM
• Janus (RR Software)
• AdaMagic (SofCheck)
• Green Hills
• DDC-I
• ICC
• XGC

• 7-Zip
  
• KZip
  
• Zip (info-zip)
• DeflOpt