[HTC One V] mcgi5sr2:
rom.zip File Structure

WIP

OK lets get started with the basics. Download a flashable rom.zip file and start poking your nose where it didn't belong before. If your ready yo get down and dirty just go ahead and unzip it into its own folder. Depending on what rom.zip you have will depend on how much of the file structure below you will see:

and here we have the root of the flashable.zip starting from the top we have:

data: this contains anything that is already signed and not part of the original build but that we want to install with the rest of the rom

META-INF: Full of all the meta information you could ever dream of. This contains all the certification and signing files along with our most important file of the install script.

system: This contains all the files that actually make up our ROM so this is everything above the HAL (Hardware Abstraction Layer). In here are the goodies I will describe how to play with later.

boot.img: Is the all important kernel, if you are S-OFF this will flash on install, if not you will need to use fastboot to flash it separately.

So if your unhappy with all of this and want out of the woods already then you can just re-zip the files back together and they will work fine, no harm done. If not the lets move onto the easy folder data. I say easy because we can't break anything here, if you get it wrong then the packages here just won't install.

DATA

So as we can see above, we have a folder called app, which is full of a load of packages that I wanted to include into the rom, but and this is the important part. I didn't want this apps to be system apps, this means I wanted them to be easy to remove without using root access. As you will see system apps live somewhere else, not totally unlike the system/app folder :silly:. Another important point is that the apps/packages, I will use these terms interchangeably, that get installed from here are all signed, this means they have a signature in there meta.inf files saying that they have not been messed with. Most app developers will sign there work, to help keep it safe, and stop people from pirating it with such ease. All apps from the playstore are signed in such a manner. The apps in other folders must not be signed, but we will get back to that. If you have any apps or packages you have got the .apk from XDA thread or elsewhere this is one of the best places to put them if you want them to install with your rom.zip

So the truth be told, I have no idea what other folders you can put in aside from the app one, but I am sure there are plenty, if you find any let me know.

NEXT, we have the META-INF folder:

META-INF

Here as mentioned we have or CERT.SF which is a certification file, our MANIFEST.MF which is the manifest ie list of everything going into this rom, and CERT.RSA another signature file. DON'T BE MESSING WITH THESE. They are core to the install process, and generated by the build scripts used to create the rom in the first place. You can open and look at them all, which will help your general understanding and break nothing, however No saving the files.

Above is the full expanded file structure, again there is really nothing you want to mess with in here, but I'll explain what I know about them. First up is the:

Android folder files, which these cover the Over The Air (OTA) update information, this is just some data that identifies what version etc of the rom for what phone you are using. It used to make sure you get the right ota update, in this rom I haven't set up ota as I have literally no idea how.

google folders stashed in the second android folder are the updater files, this is effectively a list of what the recovery program is to do when installing the rom, so you will even find the lovely message that gets printed as your rom installs saying its all going well.

This leaves us with the most important of all the folders, the system folder. In here as mentioned before are all the golden nuggets that make the trove that is your rom. Lets take a peek.

As we would be hoping the folder is full of goodness! Taking it from the top we have:

SYSTEM

system/addon.d This contains shell scripts (Ones that would run in your terminal) here we have the 50 - slimupdate.sh slimupdate script, again for OTA but this backs up the hosts (I'll get to this later) file so that it is re-instated after the upgrade. Secondly we have the 81-aio_gapps.sh which backs up the gapps that you had installed before the ota update. So they can be put back afterwards. Feel free to open these look around, and if your not doing any ota they are pretty useless.

APP

system/app This is a very significant folder as it contains all the apps that will run as part of the system, in here you'll find the dialer phone.apk, the google search package velvet.apk, the google play store vending.apk and your text messenger mms.apk. All of these files are important, come unsigned as they used to be unavailable on the playstore, and for other important reasons I am unaware of. The important part is that when we start to think about editing them with apktool, or you make your own they stay unsigned them.

The system folder is protect as read only (-ro) so that these files are not available to be changed during normal use of the phone. Of course using esExplorer or another root explorer you can change the -ro mount setting to -rw allowing you to write to the folder as well, and so change the files.

I will be happy to answer any questions as to what .apk file relates to what if you are stuck at any point. You can remove and re-install these as you wish, but be warned remove the sytemUI.apk will result in very limited functionality on the phone, which is why I will be talking it up a bit later. Its also worth noting that different roms use different android versions of the .apk and they won't always play nicely together. Whats more some of the .apks are reliant on each other, for instance googles gallery.apk and camera.apk have cross funstionality, as do mms.apk, phone.apk, contacts.apk, and contactsprovider.apk, as they share usage and files.

BIN

Just like in your linux file directory the bin folder holds all the functions and programs that get called throughout the day to day use of android. As an example adb and the backuptool are in here. Again I would advise not messing with these files, but be aware that when your trying to add new packages or functionality to a rom you may find yourself adding files or functions in here.

/-- OK enough for now I'll get back to this --/