Extend Utils

Overview

Extend Utils provide a variety of tools to manipulate Extend, Overlay and Swap files. These are generally loop-back files stored on SD card for various purposes which include, but is not limited to:

• OS Extends - running another distribution on top of Angstrom in a chroot environment.
• Dev Extends - a method of providing dev tool support without installing directly to NAND.
• File system Overlays - redirect writes from NAND to a file on an SD card.
• Swap - use a swap file on SD card to provide additional memory for the Pandora when needed.

This page used to only document OS Extends... it will now document all facets of the Extend Utils.

Extend Utils have been written by Stuckie and while very much work-in-progress, the scripts are very useful in day to day tasks.

Bug Reports

In order for a bug report to be useful, I need the following information from you:
Output from "dmesg | tail", "mount" and your preMount script.
A description of the error.

Just PM me them on the GP32X boards, or post in the relevant threads - Links at the bottom of this page.

Available Files

The current ExtendUtils will always be on my website here: Extend Utils

For support, please direct questions to this forum thread: Extend Utils on GP32X
Older threads where all this came from are at the bottom of this page for the interested.

Empty Extends

The following files are pre-formatted ext2 files. These are included in Extend Utils, but are available here as well as they're just loop files and can therefore be used with other things:

• 256MB Extend
• 512MB Extend
• 1GB Extend
• 2GB Extend
• 4GB Extend

Dev Extends

All Angstrom-based Dev Extends are currently deprecated as of 26th June 2011.

Please see the Lenny Debian OS Extend instead.

OS Extends

Debian

Lenny Dev Extend

• 512mb Lenny Extend
• 1GB Lenny Extend

The Lenny Dev Extend has a Debian bootstrap with dev tools ( enough for the Wakebreaker GL ES example plus gtk 1.2 dev )
About 400mb is taken, so choose the 1GB extend if you think you'll need lots of additional libraries.

Alternatively, check the Debian On SD project for booting Debian directly from SD card.

Step-by-step guide

In this guide, you will mount a Lenny Dev Extend (to give you a protected dev environment), in conjunction with a 1gb overlay home extend (to give you room in which to place your files).

Part 1: the 1GB home extend

1. Download ExtendUtils.pnd to your Pandora (see here for instructions on where to place PNDs)
2. Run it. It's called "Extend Utils" and is in "System" category.
3. Select "New Extend/Overlay/Swap"
4. Select "New Overlay File"
5. Select a size (for example, 1gb) .. if you select "Custom", prepare for a long wait.
6. Place the file somewhere on your SD card (the default folder it suggests is a good choice, because it always looks there first) and give it a name. For example, "1gb"... you don't need to add .overlay or .extend, as it does it for you.
7. It'll now either extract a premade empty file, or if you selected "Custom" it'll DD a new file, taking forever, and probably raping your SD in the process.. you have been warned ;)
8. You'll be pushed back to the main menu now.
9. Select "New Pre-Mount"
10. Select "New Overlay Mount Script"
11. Select "Standard Home Overlay"
12. Choose your file ("1gb.overlay" in our example) that you saved on your SD card in the previous stage
13. Save the mount script anywhere you like, calling it anything you like... for our purposes, save it in the same folder as before and name it "1gb"
14. Back to the main menu.
15. Select "Mount Existing Pre-Mount". Note: If your SD card is formatted to anything other than ext/2/3/4 (for example, if it uses FAT32 or NTFS), you can't run it directly from the Terminal. You'll need to run it through Extend Utils or type /bin/bash /my/mount/script.preMount instead.
16. Choose the script you saved in the previous part ("1gb.premount")
17. Type your sudo password (your password to log in to your Pandora at startup)
18. That should be it.

For checking purposes:

1. Launch a Terminal (start menu -> Terminal)
2. Type mount
3. Look for a line at the bottom reading something like "aufs on /home type aufs (rw, si=xxxxxxxx)"
4. Type cd /tmp/NAMEOFOVERLAY.overlay/YOURUSERNAME (for our example, if we were stuckie: cd /tmp/1gb.overlay/stuckie)
5. We'll put a random file here to ensure it works. Type in touch testfile. This will create an empty file named "testfile". Type ls and it should be among the files listed. Now type ls ~, and it should also show up.

Part 2: Debian Dev Extend

1. Download DebianDevExtend.pnd to your Pandora.
2. Download the 512mb or the 1GB Lenny Dev Extend, unzip it (for example, using Squeeze), place the file ("debian.lennydev.20110626.extend" for 512mb, "debian.lennydev.20110629.1gb.extend" for 1GB) into the directory /media/yourSDcard/pandora/appdata/DebianDevExtend (it doesn't matter where you put it, but this is easier because it's the default directory it will look in)
3. Launch Debian Dev Extend. It's in the "System" category.
4. Click "Ok" past the notifications.
5. Select the file (named "debian.lennydev.20110626.extend" or "debian.lennydev.20110629.1gb.extend").
6. Type your sudo password if prompted (you may be quick enough to still be in the sudo cache that it doesn't ask). Once you're done, a Debian Dev Extend terminal will open.
7. In the Debian Dev Extend terminal, type gcc to ensure that it works. If it says gcc: no input files, all is well.
8. Type cd to jump directly to your home folder. Type ls to ensure our test file is there. If it is, you're good to go.
9. Your new password while you're in the Debian Dev Extend terminal is pandora, so remember that if you're planning to do any sudo commands! For example, to add new libraries you would type in sudo apt-get install nameofpackage. You can search which packages are available at this page

How it all links together

You can open a file manager (for example Thunar, or Xfe) and verify that everything is as it should be. Here's how it should look:

• The contents of /home and /tmp/1gb.overlay should be almost identical
• The contents of the following three directories should be identical:
  • /home/username
  • /tmp/debextend/home/username
  • /tmp/1gb.overlay/username

("username" represents your username)

Extend Utils Help

Extend Utils ( version 1.0a ) now facilitates the creation of "PreMount" scripts. For users of previous Extend Utils script sets, these separate scripts are essentially a PreMount script - the Ubuntu specific variant being a prime example.

This allows us to create customised mounting procedures - such as being able to mount multiple Extends and Overlays at once; for example, a compressed Base OS Extend with perhaps an Overlay on top to "catch" installed programs.

Unfortunately, as is always the case with more customization, the complexity has shot up. This guide will help you to create a PreMount script given four common scenarios: a Swap mount, a Home or Root Overlay, an OS Extend and a Dev Extend.

Creating a Swap PreMount

Perhaps the simplest PreMount script is a Swap Mount. For this, I shall assume you have not created a .swap file.

1. Start up Extend Utils.
2. Select New Extend/Overlay/Swap.
3. Select New Swap File.
4. Select 256MB - this uses one of the pre-created zipped Extend files, whereas Custom will create a new one on the card.
5. Save the file anywhere you like.
6. It will extract the appropriate zip to where you selected.
7. Back at the Main Menu, select New Pre-Mount.
8. Select New Swap Mount Script.
9. Find your Swap File you just created.
10. Select a location for your Pre-Mount script to be saved to.
11. Finally, back at the Main Menu, you can select Mount Existing Pre-Mount.
12. Find where your Pre-Mount script was saved to, and that's it.. you have swap mounted.

Obviously, now that the script is saved, you only need to repeat the last two steps, or just run the script direct from the Terminal.

Creating a Root or Home Overlay PreMount

Again, I shall assume that you do not have any pre-made .overlay files.

1. Start up Extend Utils.
2. Select New Overlay.
3. Select New Overlay File.
4. Select 1GB - or whatever you like.. again be aware that Custom may very well chew through your SD card as it DD's direct to it!
5. Save the file anywhere you like.
6. It will extract the appropriate zip to where you selected.
7. Back at the Main Menu, select New Pre-Mount.
8. Select New Overlay Mount Script.
9. Select either Standard Home Overlay or Standard Root Overlay.
10. Find your Overlay that you created.
11. Select where you want to save the Pre-Mount script.
12. Finally, back at the Main Menu, you can select Mount Existing Pre-Mount.
13. Find where your Pre-Mount script was saved to, and that's it.. either the majority of / or your /home is bound to the overlay.

Creating an OS Extend PreMount

Generally, these will have been pre-made downloads, or you'll have created a chroot environment and wrapped it in an extend already. It's also important to note that there are essentially TWO types of OS Extends - compressed and uncompressed. Compressed OS Extends should be affixed with compressed; base-debian-sid-compressed.extend for example, which donates it's a base install of debian sid, in a compressed extend. Compressed extends can only be mounted as read-only, and will likely fail if you try to mount them read-write. This means they require an Overlay in order to be much use. As such, I will describe a "classic" uncompressed OS Extend procedure, and a "modern" compressed OS Extend procedure.

Compressed OS Extends

1. Start Extend Utils.
2. Select New Pre-Mount.
3. Select New Extend Mount.
4. Select OS Extend.
   This is where you need to start paying attention as to what you're doing.
   For our purposes, we want a basic configuration for say a Base Debian Sid Extend, and one Overlay.
   The Base Debian Sid Extend we would have downloaded already, and the Overlay we should have created as well.
5. Move the slider to select 1 Read-Only Extend.
6. Select our base-debian-sid-compressed.extend ( assuming you've downloaded it, and it's been released! )
7. We don't want any Read-Write Extends, so Cancel or select 0.
8. We do want an Overlay, so select 1 Read-Write Overlay.
9. Choose the Overlay you want to use.
10. Now you must name the mount point. This can be anything you like, but it must be unique and not the name of the Extend or Overlay you've chosen.
11. You'll then be asked where you want to save the PreMount script.
    Again, we need to pay attention as to what we want here.
    For our purposes, we just want a Terminal, so that we can call apt-get and install whatever we feel like, and run it from the shell to interact with the program in Angstrom.
    You can, of course, re-do this procedure later after having installed a window manager and desktop manager ( IE: something like Fluxbox and GDM ) so that you can jump fully into Debian if you so wish.
12. Select the Terminal option.
13. You'll now be sent back to the Main Menu, where you can now select Mount Existing Pre-Mount.
14. Select your Pre-Mount Script you've just created.
15. After the gksudo checks, you should have a Terminal open inside your OS Extend, where all writes go to your Overlay.

Uncompressed/Classic OS Extends

These ones are much easier to deal with, and are generally what have been released up till now. These don't require an Overlay ( though you can still use one if you like. ) The procedure for setting up a mount script for one of these runs as follows:

1. Start Extend Utils.
2. Select New Pre-Mount.
3. Select New Extend Mount.
4. Select OS Extend.
   As said, we don't need an Overlay, and Uncompressed/Classic Extends can be mounted Read-Write without any issues.
   Therefore, we only need to select 1 Read-Write Extend, and 0 everything else.
5. We don't want any Read-Only Extends, so Cancel or select 0.
6. We do want a Read-Write Extend...so move the slider to 1 and find your Extend file.
7. Again, we don't want an Overlay, so select 0 or Cancel it.
8. Now you must name the mount point. This can be anything you like, but it must be unique and not the name of the Extend.
9. You'll then be asked where you want to save the PreMount script.
   Now we need to know roughly what's in our Extend.. to be safe, we can just choose a Terminal as that's guaranteed to work. If, however, you know that GDM is installed and setup ( I'll ensure that any of my Extends that are, are documented in saying so ) then you can choose the GDM option.
10. We'll assume we've got GDM present, so select GDM.
11. You'll now be sent back to the Main Menu, where you can now select Mount Existing Pre-Mount.
12. Select your Pre-Mount Script you've just created.
13. After the gksudo checks, GDM will start up alongside Angstrom and ask you to login. You should have a login/password already - either from you manually setting it up, or the default that whoever set the .Extend up performed.

Creating a Dev Extend Pre-Mount

Dev Extends are essentially Root Extends these days.. however that's not to say there won't eventually be packs so that there's a base Dev Extend with just the bare essentials, then addons for GTK, QT, wxWidgets, etc.. so having them classed as an Extend seems like the best option.

The current Dev Extends are created exactly like the Uncompressed/Classic OS Extends, but for completeness sakes:

1. Start Extend Utils.
2. Select New Pre-Mount.
3. Select New Extend Mount.
4. Select Dev Extend.
5. Select 0 Read-Only Extends.
6. Select 1 Read-Write Extend.
7. Find your Dev Extend.
8. Select 0 Read-Write Overlays.
9. Come up with a mount point.
10. Save your Pre-Mount somewhere.
11. You may now load it up through the Mount Existing Pre-Mount script if you so wish.

Links

• Original OS Extend Thread
• Original Dev Extend Thread
• Original Overlay Thread