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============================= Zoom 5.3a ============================== ====================================================================== A floppy disk tracking and archiving utility, written by Olaf `Olsen' Barthel of MXM. © Copyright 1990,1991 by MXM, Lh data compression/decompression code © Copyright 1990,1991 by Holger P. Krekel & Olaf Barthel. Shareware, all rights reserved. No guarantee of any kind is made that the program(s) described in this document are 100% reliable. You use this material on your own risk. ======================= READ THIS OR MISS OUT ======================== ====================================================================== On startup `Zoom' will examine its internal hunk structures: if anything is not in its correct place both programs will put up alerts. To discover what was wrong enter `Zoom SELFTEST'. Enter `CRC Zoom' to calculate the external checksum and compare it with the sample given in this document. Any difference indicates possible virus infection! If you don't trust the sample checksum listed in this document, send me a letter or electronic mail (adresses listed below) and ask for the `factory checksum'. THIS AND THE FOLLOWING ZOOM! RELEASES MAY ONLY BE DISTRIBUTED IN THE SELF-EXTRACTING ARCHIVE FORM!!! ============================== Contents ============================== ====================================================================== This package consists of four files. The CRC checksums were obtained using the `CRC' utility (also included in this package). Provided that all checksums match the following samples (and this document has not been modified) no file is virus-infected. Release Date: 13-Dec-91, 19:49 Zoom (CRC = $9466EC9D, Size = 80032 Bytes) Zoom.info CRC (CRC = $4F5177B9, Size = 4104 Bytes) Zoom.doc (Size = 30370 Bytes) The `CRC' utility will also calculate and print the so-called `WRAP' checksum. For all programs in this distribution (including `Zoom' and `CRC') this checksum MUST be zero (if nonzero, the approriate file has been modified). All programs in this distribution are PURE, I suggest setting the `p' bit if not already done. ==== Why use `Zoom' instead of other disk compression utilities? ===== ====================================================================== - `Zoom' performs much faster and compresses better than any other currently available disk archiving utility. - `Zoom' recognizes about 180 different viruses and custom bootblocks. - `Zoom' has both an Intuition and a Shell interface. - `Zoom' can be customized for your own needs. - `Zoom' works with Kickstart 2.x! - `Zoom' will also work on Amiga computers equipped with an MC68020/30/40 microprocessor. No need to buy an extra version! ========================= About this release ========================= ====================================================================== I must admit that the previous `Zoom' releases would not work quite as correctly as advertised. Revisions previous to v4.2 would occasionally produce corrupt disks when decompressing archive files. In revision 4.2 the byte run precompressor was removed, curing the `corrupt' disk problem. As an unpleasant side effect compression performance and speed dropped. The reason for the trouble caused by the precompressor was never quite clear and the original Author (K. Wiesel) is certain that it works in its unmodified form. In the course of events I was told to remove the remaining original decompression code and so I did. A couple of weeks ago I was encouraged to rewrite `Zoom' and to replace the previous byte run precompressor with a different precompressor. In the course of events `Zoom' and the corresponding file format were greatly enhanced. Among other features the program now sports support for sector header labels and uses 32 bit checksums. The user interface was rewritten to support the Kickstart 2.x new look. The `ZoomCheck' program was removed from the distribution, its functions have been integrated into `Zoom'. Due to changes in the output file format files created with the current `Zoom' release cannot be decompressed using previous `Zoom' releases. `Zoom' v5.3 will still read and decompress old style disk archive files provided that they do NOT CONTAIN any run-length encoded data since the original decompression routine had to be removed on request by the original author. ============================== Purpose =============================== ====================================================================== Disk archiving utilities are becoming increasingly attractive. Almost all other disk compression tools lack a friendly user interface, take ages to finish their work or simply produce very long output files. `Zoom' uses highly-efficient data compression routines derived from LhArc (adaptive Huffman squeezing) which have been converted into MC680x0 code (we call it `Lh'). Data compression/decompression is always much faster than displayed by programs such as Warp, LhWarp, LhArc and older versions of LZ (that is, before Jon Forbes tweaked the compression algorithm). To reduce the chance of compressing a virus-infected disk, `Zoom' will examine the bootblock and display it if it is of nonstandard type. The following 180 different bootblock viruses and custom bootblocks are recognized: 16BitCrew Saddam Hussein 2001 Virus SCA AEK (MicroMaster) ScarFace AIDS Virus Sendarian AlienNewBeat SuperBoy AmigaFreak Supply Team anti Ass 1.0 Switch Off Australian Parasite Target Bamiga Sector One TelStar BlackFlash 2.0 Termigator Blizzard 1.0 TimeBomb BlowJob Tomates GenTechnic Butonic 1.1 Traveller 1.0 ByteVoyager 1 Turk 1.3 ByteVoyager 2 UltraFox ByteBandit 1 Vermin ByteBandit 2 VirusHunter anti ByteBandit 3 VirusSlayer 1.0 ByteWarrior (DASA) VKill 1.0 ByteWarrior FastLoad WarHawk CCCP Link+Boot ACID Terminator 1.0 ClaasAbraham ACID Terminator v3.0 CList Alcatraz Megademo 3 Coders Nightmare Antitrax 2010 Demo DiskDoktors Atomic Soft Virus Detector DAG Avirex Destructor Betrayal Proboot v1.0 Digital Emotions BootBug v0.1 DiskGuard 1.0 BootBlock Generation Disk Herpes (Phantasm) Bootgirl FAST 1 BootIntro 1.2 FAST 2 BootIntro NextGen F.I.C.A. BootOut 5.5 Forpib Boot-Tune Gadaffi Budbrain & New Dimensions 35 MAD II CCS Boot v2.0 Graffiti CCS Boot v3.0 Gremlin DevWare GXTeam Dietmar Noll ClearMem HCS 4220 DOC 1989 Hilly Dragons Megademo I Ice Breakers Dugger Incognito International Soccer Inger IQ Invisible Brain Boot-Copy JITR License to kill Joshua 1 Mad Monks Super Bob-Intro Joshua 2 Memory Controler 1.2 Julie (Virus Predator) Memory Allocator v1.3 Kauki No FastMem Kefrens Nomad Utility Boot v1.0 Lamer Ext. 1 Northstar Checker Lamer Ext. 2 Outlaw Checker v1.42 Lamer Ext. 3 PAL Boot Lamer Ext. 4 Paradroid 90 Lamer Ext. 5 Phenomena Enigma demo Lamer Ext. 6 Phenomena megademo 1 LameStyle UK Pinball Wizard LSD Powerslaves Demo 1 M&U 5.5 PvL Virus Sound M&U 6.1 Quartex drives off MegaMaster Razor 1911 Observe Mexx RSI Megademo Disk 1 MicroSystems RSI Megademo Disk 2 Morbid Angel Scoopex Bootintro NorthStar 1 Scoopex Mental Hangover NorthStar 2/3 Scoopex PALBoot v2.0 NorthStar anti Seek & Destroy Bootcheck v1.0 Obelisk 1 Seek & Destroy Drive Control v1.0 Obelisk Format Sinister Syndicate Opapa Slipstream Utility Boot v4.0 Paradox 1 (Logic Bomb) Slipstream Utility Boot v6.1 Paradox 2 Squash 4.3 Paratax I SysNot Paratax II TAL Bootleg v2.1 Pentagon Circle 1 The Sect Mega Concert Pentagon Circle 2 TLC Demosample Pentagon Circle 3 UDC NoVirus Boot v1.0 PowerBomb (BB 2.0) UDC Utility Boot v1.0 PvL 3.0 anti Ultimate Boot Writer PvL 4.0 anti Venom Bootloader v1.00a PvL 5.0 anti Virus Destructor 1 PvL 5.1 anti Virus Destructor 2 PvL 5.3 anti Viruskiller Professional v2.0 PvL 5.4 anti Vision Megademo IV PvL 6.1 anti Vortex 42 Megaboot v1.3 PvL 6.4 anti XCopy Professional PvL 6.5 anti ZeroVirus AutoAddRAM Rene ZeroVirus BigScreenTest Revenge ZeroVirus Message Revenge BootLoad ZeroVirus NoFastMem `Zoom' will put up an alert if it finds one of these bootblocks on a disk to be compressed and will ask you whether you wish to have the suspicious bootblock data replaced in the compressed disk archive or not. If you choose to replace it, `Zoom' will use a standard Kickstart 2.x bootblock in place of the original data. While this bootblock is different from the Kickstart 1.3 bootblock, it is still compatible with older Kickstart revisions. ============================ Installation ============================ ====================================================================== Copy `arp.library' to your LIBS: directory, `Zoom' requires it. ENV: (default AmigaDOS environment storage directory) should be assigned to somewhere, but needn't. ======================== `Zoom' Shell usage ========================== ====================================================================== The following command line template is displayed if you type `Zoom ?': From,To,Check/K,T=Text/K,S=Start/K,E=End/K,C=Crypt/K,D=ClearData/S, B=ClearBlocks/S,V=Verify/S,L=SecLabels/S,Q=Quiet/S,N=NoPrompt/S, Selftest/S From .......... Name of the file to be read and written back to disk or the name of the filing device to read the data from to be compressed: Examples: `Zoom from df0: to ram:doodle' `Zoom from ram:doodle to df0:' If possible, `Zoom' will try to determine if source and destination overlap. You will be notified if you are about to decompress a file residing on the destination disk or to create a file on the source disk to be compressed. To ............ Name of the device to store the decompressed data on or the name of the file to send the compressed data to. Check ......... A file created by `Zoom' will be read and tested. If a checksum is not in its correct place an error message will be displayed. Unless the `Quiet' switch is used a text file attached to the `Zoom' data file in question will be displayed as well. Example: `Zoom check ram:doodle' Text .......... `Zoom' can attach a text file to an archive file which will be displayed while/before data decompression. It will be read and compressed before the actual disk compression takes place. Start ......... The track number to start compressing at. This argument is optional and does not need to be entered. By default the starting track is zero (= 0). Example: `Zoom df0: to ram:dodo start 17 end 22' End ........... The number of the last track to compress. Note that you cannot ask for a starting track and omit the ending track (and the other way round). Both arguments must be used. Crypt ......... Files created by `Zoom' may be encrypted with a special password. The same password (Note: it is case sensitive) will be required to decompress the output file. Example: `Zoom df0: to ram:doodle crypt Secret' Cleardata ..... This switch may reduce the size of the output file produced by compression. Under the `old' filing system a data block contains the number of bytes which are actually occupied by data. The rest of the data block usually contains random data. If this switch is active the unused portion of the data block will be set to zero. Note: due to the different data block format this switch has no effect if used on a disk formatted by the fast filing system. Clearblocks ... Not all blocks of a disk may be actually occupied by data. `Zoom' uses the disk Bitmap to determine which blocks to read and to compress. By default the Bitmap is ignored. This switch will cause `Zoom' to skip unused blocks. Note: this feature will be disabled if the disk to be compressed is not a valid AmigaDOS disk with a properly initialized root/boot block and a valid Bitmap flag. Also important: this switch has no effect if a set of tracks is to be compressed instead of the default 0..79. Verify ........ Each write access to disk will be verified if this switch is active. The actual data verification will be handled by the blitter, so it won't slow down the decompression process too much. SecLabels ..... `Zoom' will automatically compress sector label information along with each track it reads if the disk to be compressed is not a standard AmigaDOS format disk or the `Clear Unused Blocks' switch has been disabled. In order to restore the sector label information during compression, the destination disk has to be formatted. `Zoom' will format the disk for you if the `Format Sector Labels' switch is active. To save much time, you could turn this switch off and format the disk to write to before submitting it to `Zoom'. Quiet ......... If this switch is in effect, `Zoom' will not display text files attached to data files during decompression. NoPrompt ...... By default `Zoom' will prompt the user to insert the source/destination disk to be used for compression/decompression. If the `NoPrompt' switch is in effect, `Zoom' will not wait for the user to press return, compression/decompression will immediately. Selftest ...... This shell option was added to help you to verify if your `Zoom' program has been infected by a virus. `Zoom' will examine its internal hunk structure and complain if a hunk is not in its standard size or place. These are conditions which can, but need not indicate link virus infection. While this technique does not entirely prevent the creation of trojan horse-versions of `Zoom' or that an extremely `clever' virus infects `Zoom',it will probably catch all `dumb' link viruses which put their virus code in front of the first hunk or behind the last hunk of a program. ====================== `Zoom' Workbench usage ======================== ====================================================================== If called from Workbench (or from Shell without any arguments) a window will pop up under the mouse pointer containing the following gadgets: Select File ........... Select the name of the file to be compressed/decompressed. It will be put into the string gadget to the right of this button. Select Drive .......... Select the the drive to read/write the data to be compressed/decompressed from/to. This button will cycle through all filing systems which match the typical size and track definitions of the builtin 3.5" disk drive. The name of the filing system will be put into the string gadget to the right of this button. Enter Password ........ Will put up a requester in which the password to be used for data compression/decompression can be entered. The program will refer to this password when decompressing encrypted files and will prompt for a new password if the password does not match the encryption key. If enabled (e.g. the `Encrypt Output File' switch is active) the program will use this password for output file encryption. Select Text File ...... Select the text file to be prepended to all output files, note: in order to use this feature, the `Include Text File' switch must be active. Start Compression ..... Click this button to start data compression, click it again to stop the process. Start Decompression ... Click this button to start data decompression click it again to stop the process. Start File Check ...... Will read and examine the current `Zoom' output file to detect file defects. Start File View ....... will read the current `Zoom' output file and display the text file attached to it (if any). From Track To Track ... The starting and ending tracks to compress, note that this feature has to be selected explicitely. Clear Unused Data ..... Unused data in standard file system blocks will be set to zero if this feature is enabled. Clear Unused Blocks ... Unused blocks will be skipped if this switch is in effect. Note: cannot be mixed with `from track to track'. Verify Write .......... Enables write verification while data files are decompressed. This switch has no effect during data compression. Include Text File ..... If enabled, `Zoom' will prepend a text file to be specified with the `Select Text File' button to each output file it produces. Encrypt Output File ... To have the output files `Zoom' produces encrypted with a password turn this switch on and enter an access key using the `Enter Password' button. Format Sector Labels .. `Zoom' will automatically compress sector label information along with each track it reads if the disk to be compressed is not a standard AmigaDOS format disk or the `Clear Unused Blocks' switch has been disabled. In order to restore the sector label information during compression, the destination disk has to be formatted. `Zoom' will format the disk for you if the `Format Sector Labels' switch is active. To save much time, you could turn this switch off and format the disk to write to before submitting it to `Zoom'. The display on the right hand side of the `Zoom' window contains the following elements: Free Disk Space ....... The space left on the destination drive. Available Memory ...... System memory currently available. File Size ............. The size of the compressed data file. Track Size ............ Size of the last compressed/decompressed track(s). Usually two values will appear here: the first one denotes the size of the buffer after pre-compression, the second value indicates the final size after Lh-compression. Compression Ratio ..... This display denotes the amount of data saved during compression. Note: this value refers to the entire output file. Current Track ......... Current track counter. Elapsed Time .......... Time elapsed during data compression or decompression. Status ................ The action currently executed. If an output file does not fit on the destination disk, compression wil be terminated. The starting and ending tracks will be adjusted accordingly to allow the user to continue to compress the disk where the first compression run stopped. The `name' of the file to be decompressed may be a wildcard expression. `Zoom' will try to locate and decompress all files which match the pattern (note: only the Intuition interface supports this feature). Multiple selection is supported as well: to decompress a row of `Zoom' output files, hold down the shift-key, click the icons of files you wish to decompress, then double-click the `Zoom' icon. Note: `Zoom' will use the default options to decompress the files, the online options can only be changed after all files have been processed! ================ The `ZOOMOPTS' environment variable ================= ====================================================================== The current settings displayed in the Intuition interface are saved in a default environment variable which is read again when `Zoom' is called again. This variable is set both in Manx/ARP and in Workbench 1.3 format. The following template is supported: File/K,Drive/K,Start/K,End/K,TextFile/K,ClearData/S,ClearBlocks/S, Verify/S,IncludeText/S,Encrypt/S,SecLabels/S,NoIcons/S File .......... The default string to appear in the `File name' gadget. Drive ......... The string to appear in the `Drive' gadget. Start ......... The first track to start data compression with. End ........... The last track to compress. TextFile ...... The name of the text file to be attached to each output file produced. ClearData ..... Whether unused block data is to be zeroed or not. ClearBlocks ... Whether unused blocks are to be skipped or not. Verify ........ Whether write verification is enabled or not. IncludeText ... Set this flag if you want `Zoom' to include text files with each output file it produces. Encrypt ....... Set this flag if you want `Zoom' to encrypt each output file it produces. SecLabels ..... Set this flag if you want `Zoom' to format a disk before decompressing a file which contains sector label information to it. NoIcons ....... Set this flag if you don't want `Zoom' to create icons for each output file. A sample `ZOOMOPTS' value is: `FILE RAM:Blank.zom DRIVE DF0: CLEARDATA CLEARBLOCKS' `Zoom' will prefer to set/examine the the `ZOOMOPTS' environment variable in the AmigaDOS 1.3 standard. If this is not possible `Zoom' will set/examine the Manx/ARP standard environment variable instead. ========================== Technical notes =========================== ====================================================================== `Zoom' needs approximateley 240K bytes of memory to perform its jobs. Make sure that enough space is available, or `Zoom' will complain. Note that disabling write verification will save about 10 KBytes of chip memory. The Lh data compression/decompression routines are related to LhArc and PKZip. Unlike common data compression/decompression routines such as employed by PowerPacker or Imploder, the performance of Lh cannot be downgraded by adjusting the data sequence search depth. This means that Lh will always compress trying to achieve the best results with the maximum effort. The byte-run compression/decompression code will fit entirely into the instruction caches of the MC68020/68030/68040 processors, which means that both compression and decompression time will go almost unnoticed. ======================= How fast `Zoom' works ======================== ====================================================================== I suppose you are shocked by the amount of memory required for data compression / decompression. Well, as it turns out I traded speed for memory. I tested `Zoom' (compressing a disk) against DMS 1.02 (running in medium mode), LhWarp 1.4 and Warp 1.2a with the following results: Workbench1.3D: Tool | Output file | Time -------+--------------+-------------- Warp | 496990 bytes | 11:49 minutes LhWarp | 399889 bytes | 16:39 minutes DMS | 480952 bytes | 11:00 minutes Zoom | 383230 bytes | 6:15 minutes ============================== Credits =============================== ====================================================================== Credits go to Ralf Thanner who kept nagging until I finally started to rewrite `Zoom', who also collected a list of most useful features you can now find implemented in `Zoom' and who also organized the code contributions without which `Zoom' would lack a great part of functionality, to Henning Leise who contributed the excellent new precompression code, to Georg Hörmann who donated his fine bootblock virus recognition code, to Erik Løvendahl Sørensen for maintaining the Amiga virus library, to Martin Berndt, who discovered the last errors before `Zoom' went for release, to Arp programmers for the Arp 1.3 package without which `Zoom' would have been much more difficult to implement and last but not least to all the beta testers. ================= Author's request and Gift-Ware fee ================= ====================================================================== `Zoom' is released as Gift-Ware. If you like the program and use it frequently, send a gift of any kind which you think will do as a payment for the program to the author: Olaf Barthel Brabeckstrasse 35 D-3000 Hannover 71 Federal Republic of Germany If an error shows up, do not hesitate to contact me as soon as possible. My `real world' adress is given above, the following are my EMail addresses: Z-Netz: O.BARTHEL@A-Link-H Usenet: o.barthel@a-link-h.zer.sub.org cbmvax.commodore.com!cbmehq!sourcery!olsen The entire `Zoom' package may be noncommercially redistributed, provided that the package is always distributed in its complete form. A small copy fee for media costs is okay but any kind of commercial distribution is strictly forbidden! Comments and suggestions how to improve this program are generally appreciated!