mirror of
https://gitlab.com/freepascal.org/fpc/source.git
synced 2025-04-05 11:18:18 +02:00
225 lines
8.2 KiB
Plaintext
225 lines
8.2 KiB
Plaintext
Contents:
|
|
zipper.pp/TZipper
|
|
- Introduction
|
|
- Zip standards compliance
|
|
- Zip file format
|
|
- Zip64 support notes
|
|
paszlib
|
|
- Introduction
|
|
- Change Log
|
|
- File list
|
|
- Legal issues
|
|
- Archive Locations
|
|
|
|
=================
|
|
zipper.pp/TZipper
|
|
=================
|
|
|
|
Introduction
|
|
============
|
|
Zipper.pp contains TZipper, an object-oriented wrapper for the paszlib units
|
|
that allows
|
|
- compressing/adding files/streams
|
|
- decompressing files/streams
|
|
- listing files
|
|
contained in a zip file.
|
|
|
|
Zip standards compliance
|
|
========================
|
|
TZipper is meant to help implement the most widely used and useful aspects of
|
|
the zip format, while following the official specifications
|
|
http://www.pkware.com/documents/casestudies/APPNOTE.TXT
|
|
(latest version reviewed for this readme: 6.3.3, September 1, 2012)
|
|
as much as possible.
|
|
|
|
Not all (de)compression methods specified in the zip standard [1] are supported.
|
|
Encryption (either zip 2.0 or AES) is not supported, nor are multiple disk sets (spanning/splitting).
|
|
Please see the fpdoc help and the zipper.pp for details on using the class.
|
|
|
|
Zip file format
|
|
===============
|
|
The standard mentioned above documents the zip file format authoratively
|
|
and in detail. However, a brief summary can be useful:
|
|
A zip file consists of
|
|
|
|
For each file:
|
|
local file header
|
|
(filename, uncompressed,compressed size etc)
|
|
optional extended file header
|
|
(e.g. zip64 extended info which overrides size above)
|
|
compressed file data
|
|
|
|
Central directory:
|
|
- for each file:
|
|
central directory header
|
|
(much the same data as local file header+position of local file header)
|
|
optional extended file header (e.g. zip64 extended info which overrides the
|
|
above)
|
|
|
|
if zip64 is used: one
|
|
zip64 end of central directory record
|
|
(mainly used to point to beginning of central directory)
|
|
zip64 end of central directory locator
|
|
(mainly used to point to zip64 end of central directory record)
|
|
|
|
in any case: one
|
|
end of central directory record
|
|
(contains position of central directory, zip file comment etc)
|
|
|
|
Zip64 support notes
|
|
===================
|
|
The zip64 extensions that allow large files are supported:
|
|
- total zip file size and uncompressed sizes of >4Gb (up to FPC's limit of int64
|
|
size for streams)
|
|
- > 65535 files per zip archive (up to FPC's limit of integer due to
|
|
collection.count)
|
|
|
|
Write support:
|
|
zip64 headers are added after local file headers only if the uncompressed or
|
|
compressed sizes overflow the local file header space. This avoids wasting space.
|
|
|
|
Each local zip64 file header variable overrides its corresponding variable in
|
|
the local file header only if it is not 0. If it is, the local version is used.
|
|
|
|
Each central directory zip64 file header variable overrides its corresponding
|
|
variable in the central directory file header only if it is not 0. If it is, the
|
|
central directory file header version is used.
|
|
|
|
If zip64 support is needed due to zip64 local/central file headers and/or the
|
|
number of files in the zip file, the zip64 alternatives to the end of central
|
|
diretory variables are always written. Although the zip standard doesn't seem to
|
|
require this explicitly, it doesn't forbid it either and other utilities such as
|
|
rar and Windows 7 built in zip support seem to require it.
|
|
|
|
=======
|
|
paszlib
|
|
=======
|
|
_____________________________________________________________________________
|
|
|
|
PASZLIB 1.0 May 11th, 1998
|
|
|
|
Based on the zlib 1.1.2, a general purpose data compression library.
|
|
|
|
Copyright (C) 1998,1999,2000 by NOMSSI NZALI Jacques H. C.
|
|
[kn&n DES] See "Legal issues" for conditions of distribution and use.
|
|
_____________________________________________________________________________
|
|
|
|
|
|
Introduction
|
|
============
|
|
|
|
The 'zlib' compression library provides in-memory compression and
|
|
decompression functions, including integrity checks of the uncompressed
|
|
data. This version of the library supports only one compression method
|
|
(deflation) but other algorithms will be added later and will have the same
|
|
stream interface.
|
|
|
|
Compression can be done in a single step if the buffers are large
|
|
enough (for example if an input file is mmap'ed), or can be done by
|
|
repeated calls of the compression function. In the latter case, the
|
|
application must provide more input and/or consume the output
|
|
(providing more output space) before each call.
|
|
|
|
The default memory requirements for deflate are 256K plus a few kilobytes
|
|
for small objects. The default memory requirements for inflate are 32K
|
|
plus a few kilobytes for small objects.
|
|
|
|
Change Log
|
|
==========
|
|
|
|
March 24th 2000 - minizip code by Gilles Vollant ported to Pascal.
|
|
z_stream.msg defined as string[255] to avoid problems
|
|
with Delphi 2+ dynamic string handling.
|
|
changes to silence Delphi 5 compiler warning. If you
|
|
have Delphi 5, defines Delphi5 in zconf.inc
|
|
|
|
May 7th 1999 - Some changes for FPC
|
|
deflateCopy() has new parameters
|
|
trees.pas - record constant definition
|
|
June 17th 1998 - Applied official 1.1.2 patch.
|
|
Memcheck turned off by default.
|
|
zutil.pas patch for Delphi 1 memory allocation corrected.
|
|
dzlib.txt file added.
|
|
compress2() is now exported
|
|
|
|
June 25th 1998 - fixed a conversion bug: in inftrees.pas, ZFREE(z, v) was
|
|
missing in line 574;
|
|
|
|
File list
|
|
=========
|
|
|
|
Here is a road map to the files in the Paszlib distribution.
|
|
|
|
readme.txt Introduction, Documentation
|
|
dzlib.txt Changes to Delphi sources for Paszlib stream classes
|
|
|
|
include file
|
|
|
|
zconf.inc Configuration declarations.
|
|
|
|
Pascal source code files:
|
|
|
|
adler.pas compute the Adler-32 checksum of a data stream
|
|
crc.pas compute the CRC-32 of a data stream
|
|
gzio.pas IO on .gz files
|
|
infblock.pas interpret and process block types to last block
|
|
infcodes.pas process literals and length/distance pairs
|
|
inffast.pas process literals and length/distance pairs fast
|
|
inftrees.pas generate Huffman trees for efficient decoding
|
|
infutil.pas types and macros common to blocks and codes
|
|
strutils.pas string utilities
|
|
trees.pas output deflated data using Huffman coding
|
|
zcompres.pas compress a memory buffer
|
|
zdeflate.pas compress data using the deflation algorithm
|
|
zinflate.pas zlib interface to inflate modules
|
|
zlib.pas zlib data structures. read the comments there!
|
|
zuncompr.pas decompress a memory buffer
|
|
zutil.pas
|
|
|
|
minizip/ziputils.pas data structure and IO on .zip file
|
|
minizip/unzip.pas
|
|
minizip/zip.pas
|
|
|
|
Test applications
|
|
|
|
example.pas usage example of the zlib compression library
|
|
minigzip.pas simulate gzip using the zlib compression library
|
|
minizip/miniunz.pas simulates unzip using the zlib compression library
|
|
minizip/minizip.pas simulates zip using the zlib compression library
|
|
|
|
Legal issues
|
|
============
|
|
|
|
Copyright (C) 1998,1999,2000 by Jacques Nomssi Nzali
|
|
|
|
This software is provided 'as-is', without any express or implied
|
|
warranty. In no event will the author be held liable for any damages
|
|
arising from the use of this software.
|
|
|
|
Permission is granted to anyone to use this software for any purpose,
|
|
including commercial applications, and to alter it and redistribute it
|
|
freely, subject to the following restrictions:
|
|
|
|
1. The origin of this software must not be misrepresented; you must not
|
|
claim that you wrote the original software. If you use this software
|
|
in a product, an acknowledgment in the product documentation would be
|
|
appreciated but is not required.
|
|
2. Altered source versions must be plainly marked as such, and must not be
|
|
misrepresented as being the original software.
|
|
3. This notice may not be removed or altered from any source distribution.
|
|
|
|
|
|
Archive Locations:
|
|
==================
|
|
|
|
Check the Paszlib home page with links
|
|
|
|
http://www.tu-chemnitz.de/~nomssi/paszlib.html
|
|
|
|
The data format used by the zlib library is described by RFCs (Request for
|
|
Comments) 1950 to 1952 in the files ftp://ds.internic.net/rfc/rfc1950.txt
|
|
(zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
|
|
These documents are also available in other formats from
|
|
ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html.
|
|
____________________________________________________________________________
|
|
Jacques Nomssi Nzali <mailto:nomssi@physik.tu-chemnitz.de> March 24th, 2000 |