©1999 Jeremy Collake
All Rights Reserved.
Email: mailto:jeremy@collakesoftware.com
Homepage:
http://www.collakesoftware.com/
This software is provided as-is, without warranty of ANY KIND, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose. The author shall NOT be held liable for ANY damage to you, your computer, or to anyone or anything else, that may result from its use, or misuse. Basically, you use it at YOUR OWN RISK. Registration is required to continue using this software after a 14-day evaluation period has expired. Please see the registration information at the end of this document.
I.
Overview
PECompact is a utility that compresses Windows 9x/NT4/w2k executables and DLLs to, typically, less than half their original size while leaving them 100% functional. PECompact’d applications occupy less disk space, cost less to distribute, are loaded quicker across networks, decrease network traffic, and are more difficult to reverse-engineer and modify.
PECompact works by compressing the code, data, import directory, selected resources and other portions of Windows executables. The executable is decompressed and rebuilt at runtime with no noticeable delay. In fact, compressed executables can actually load quicker in some cases because there is less data to be retrieved from the disk or network. Both compression algorithms used by PECompact feature an optimized, 32bit x86 assembly language decompressor for maximum data throughput.
Unlike competing products, PECompact is highly configurable and gives the user much more power to select what is compressed and how it is compressed. PECompact also has unique plug-in support to allow for users to supply their own encryption/decryption procedures or special functionality to compressed executables.
For users who prefer not to compress their executables for whatever reason, PECompact also offers a “Trim Only” option that optimizes the executable structure and decreases its size without applying any compression at all! This function can optionally strip relocations from the executable.
Features
II.
Usage
PECompact
analyzes the target executable and auto-configures itself for those users who
prefer not to get involved with the intricate details of the compression.
However, to support more advanced users, PECompact is the most configurable
executable compressor on the market.
1. The Main Dialog
Function Name
Description
|
Compress Normal Application |
Compress file as a normal EXE. |
|
Compress DLL/OCX |
Compress file as a Dynamic-Link
Library or OCX control. |
|
Trim Only |
Realign and optimize the
executable structure without applying any compression or installing any
symbiotic code. Relocations are stripped from EXEs, and left preserved in
DLLs. |
|
aPLib |
Utilize Joergen Ibsen’s aPLib
data compression library. This compression library is fast and tight,
especially for files smaller than 64k. This option can also be selected by
using the command line switch “/J”. |
|
JCALG1 |
Utilize Jeremy Collake’s JCALG1
compression library. This compression library supports multiple compress
level settings and performs better than aPLib on larger files. This option
can also be selected by using the command line switch “/J-“. |
|
Compression Level |
This trackbar allows the user to
select the compression level that JCALG1 will use. A higher level (farther to
the right) will use a larger window size, thereby increasing the compression
level but decreasing the compression speed. Note that higher compression
levels will require significantly more memory during compression.
Decompression speed and memory requirements are unaffected. |
|
Browse |
Browse for and select a file to
compress or trim. |
|
Compress/Trim |
Begin compression or trimming of
an executable. |
|
Test |
Test the compressed executable,
with an option to restore the backup. |
|
Erase .BAK |
Erase backup of compressed
executable. |
|
Exit |
Exit PECompact. |
|
Advanced Configuration |
Show the advanced configuration dialog.
See below for explanation of options there. |
2. Advanced Configuration
|
Create New Section |
Places the PECompact symbiotic
code into a new section of the executable rather than the default of appending
it to the last section. Checking this option may result in a slightly larger
compressed executable. |
|
Restructure Resources |
Restructure the resources in a
more compressible format. Turning this option off will hinder compression of
some resources in the executable. |
|
Merge Sections |
Merge congruent, compressible
sections into one section to reduce file alignment overhead. Turning this
option off will result in a larger compressed executable, but slightly faster
loading. |
|
Strip Relocations |
Strip the relocations (fixups)
from the executable. It is safe to strip the relocations from EXEs, but one
should NEVER strip the relocations from DLLs. |
|
Compress Export Table |
Compress the export table, if it
exists. The export table of most DLLs should remain uncompressed. |
|
Use Windows DLL Loader |
Allow the windows loader to
process the import directory instead of the PECompact symbiotic code. |
|
Copy Overlay |
Some executables, such as setup
applications, have extra data appended to the end. Selecting this option will
cause any extra data to be copied to the end of the compressed executable. |
|
Backup File |
Create a backup of the file
before compression. The backup will be named the same as the original, except
it will have the “.bak” extension appended to it. |
|
Small/Fast Decompressor |
The small decompressor is
smaller, yet slower than the fast decompressor. The size difference is about
150 bytes, but the fast decompressor could cause an increase in executable
size by as much as 512 bytes. |
|
Plugins - Encrypt |
Select the encryption plugin. |
|
Plugins - Decrypt |
Select the decryption plugin. |
|
Plugins - Post-operative |
Select the post-operative
plugin. |
|
Finish Beep |
Emit beep when compression of a
file is complete. |
|
One Instance |
Only allow one instance of
PECompact to be active at a time. |
|
Lock Memory in RAM |
Lock allocated memory into RAM
if possible. |
|
Compressible Resources |
This list of resources allows
for selection of which resources should be compressed, and which should
remain uncompressed and preserved. |
|
All Shell Icons |
Compress all shell icons,
leaving none available for display by explorer and other applications. |
|
# of Shell Icons |
The maximum number of icons to
leave uncompressed and available for display by explorer and other
applications. Decreasing this number will result in greater compression of
most executables. |
3. Menu Options
|
Configuratation
/ Save Configuration |
Save
the current configuration. It will be loaded for all subsequent PECompact
executions, but can be overridden by command line parameters. |
|
Configuration
/ Load Configuration |
Load
the last saved configuration. |
|
Configuration
/ Restore Defaults |
Restore
the default configuration. |
|
Help
/ About |
Display
the about box and registration status. |
|
Help
/ Check For Update |
Check
for an update on Collake Software’s website. |
B. Command Line Switches
PECompact can be run without any
parameters, however it also accepts the following command line syntax:
PECompact [filename] [switches]
|
/A |
Automatically
start compression or trimming without any user intervention. |
|
/X |
Automatically
exit after compression or trimming is complete. |
|
/T |
Trim
only, do not compress. |
|
/M[-] |
Toggle
on/off section merging. |
|
/C[-] |
Toggle
on/off resource restructuring. |
|
/L[-] |
Toggle
on/off usage of windows DLL loader. |
|
/E[-] |
Toggle
on/off compression of the export table. |
|
/I[-] |
Toggle
on/off compression of all shell icons. |
|
/B[-] |
Toggle
on/off backup of file. |
|
/O[-] |
Toggle
on/off copying of overlay. |
|
/S[-] |
Toggle
on/off stripping of relocations. |
|
/R[-] |
Register
or unregister shell extension. |
|
/J[-] |
Toggle
usage of aPLib. |
|
/0-9 |
Specify
compression level for use by JCALG1. |
|
/F[-] |
Toggle
usage of fast decompression procedure. |
Command line switches override a
saved configuration.
PECompact has unique support of
plugins to allow users to add new functionality to the PECompact symbiote. This
section is briefly describes the specifications for plugin development, it is
intended for developers only.
Plugin code is read from an exported
procedure of a DLL. This code is loaded into the symbiote, with the exception
of the encryption plugin in which it is not necessary to do so. The code has
read/write access to itself, however delta offsets must be calculated because
the code will not be loaded at its default base on compile. Please see my
sample plugins, they should make everything obvious.
Of course, it is NOT necessary to
include the plugin DLLs with the compressed application.
Encryption Plugin
-------------------
Exported API: EncryptPlugin
Maximum Size: 100h
On entry:
edi->destination
esi->source
ecx=size
Preserve:
You must preserve all registers except
edi, esi, eax, and ecx.
Notes:
This plugin is executed after
compression of a section.
Decryption Plugin
------------------
Exported API: DecryptPlugin
Maximum Size: 100h
On entry:
edi->destination
esi->source
ecx=size
Preserve:
You must preserve all registers except
edi, esi, eax, and ecx.
Notes:
This plugin is executed before
decompression of a section.
Post-operative Plugin
---------------------
Exported API: PostOperativePlugin
Maximum Size: 200h
On entry:
esi->LoadLibrary
edi->GetProcAddress
Preserve:
Nothing necessary.
Notes:
This plugin is executed immediatly prior
to passing control
back to the original entry point of the
executable.
To
continue using PECompact after the 14-day evaluation period, registration is
required. All license types include free lifetime updates. To purchase
PECompact via a secure web server using a credit card, please click on the
desired license type below:
|
$15 |
Licensed
for use on a single computer for private use or for use on freeware
applications by authors. |
|
|
$30 |
Licensed
for use on shareware applications by authors. |
|
|
$140 |
Licensed
for use by software companies and teams of programmers on commercial/retail
applications. |
For
additional purchasing information please visit http://www.collakesoftware.com or
email collake@charter.net. Alternatively,
PECompact can be purchased by sending a check or money order to:
Jeremy Collake
PO
BOX 426
Talbott, TN 37877
USA