This will probably go more low-level than most people care to go, but I figured I'd ask anyway.
Android is built on the linux 2 kernel which is primarily implemented in C. What if we could go beneath the kenrel implantation in C and override device-level instructions?
I'm almost certain Motorola has an assembly language for their devices published on the web somewhere. What would be the difference in writing assembly-level instructions as opposed to reworking kernel bypasses in C?
Related
I apologize in advance if this has been suggested before, or if it's a completely off the wall idea that will never work.
Has anybody attempted to build for Dream from the morrison source provided by motorola? Could we not just do the edits before building, and add support for the method Dream uses to start wifi? I know it doesn't include all the cool blur stuff, but it does nativly supports those apps. So shouldn't we be able to add them after building?
We have yet to get bluetooth on hero roms, but HTC was never kind enough to provide the source. So we have always been working with prebuilt roms. Android is by nature platform independant, so is it just a matter of nobody wanting to put in the work? Or has motorola changed so much that it would be too challanging to accomplish this?
I'm just curious about something.
I recently moved from the iPhone to a Nexus One.
While I noticed there are a lot of ROM cookers etc (thanks for your great work guys) the development community seems kind of thin?
For example, on the iPhone there are full sets of all GNU tools. Anything you can use in Linux/Darwin they have for iPhone. There is a full apt packaging system will full console tools. The full OpenSSH suite has been made supporting all the wireless administration that I've come to love on my phone. Basically, it makes it feel like a full computer in my hand.
Now, I love this Nexus One, but I wasn't sure what the reasoning behind no one out there doing development on this kind of stuff. You'd think a phone running Linux with all code available would attract hordes of eager coders.
Instead we get weird crap like "dropbear" that has to be recompiled yourself to even work right, and even then...haha.
Not much as far as package management in the console, and our tools come from Busybox! Just seems very odd to me, but there must be reasons that I am not seeing.
This post is really not meant as an insult because I love this OS so far etc, but it just really suprised me that full sets of standard tools are not available.
Anyone know why?
Because you have to replicate the entire standard GNU/Linux userspace, which is a bear. Most of the work is done on the Android userspace instead, and you can find the fruits of those labors on AOSP Gerrit (http://r.android.com/) and the CyanogenMOD repository (http://github.com/cyanogen/android_vendor_cyanogen).
The best bet for getting a standard GNU/Linux userspace is to just boot Debian.
For future reference, this is probably not considered the correct forum for this discussion (probably Android General or the generic Android Development, not too sure.)
EDIT: Just to address some more specific points, Android has a package manager (those .apk files you see everywhere) and Busybox makes the most of the limited internal memory and provides enough tools to manage the Android userspace.
Sorry I thought the development forum would be the right place.
The iPhone 2g/3g have only 128mb of memory, and since gnu tools aren't resident in memory there is no problem having a full compliment of them on the phone.
The problem with debian is it is not really a nice UI for a phone. It would just be nice to have my phone, plus having the GNU tools underneath.
It isn't like its a dealbreaker, it just struck me as odd that all the proper tools have been built for the iPhone, and using it really feels like a full computer you're SSHing into, where as an open source Linux based OS on android basically is lacking all of it, minus the limited functionality provided by Busybox and Dropbear (like..dropbear really?).
These things have more memory and comparable processing speed to computers running windows 98 and early XP, so there is no reason not to have everything available to you when you need it.
I'm kind of a sideline commenter here as I'm not a coder, but it just struck me as odd.
Thanks for your reply!
anethema said:
Sorry I thought the development forum would be the right place.
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NP, it's side discussion though. "Here's a complete set of native GNU tools" would be a dev forum topic.
anethema said:
The iPhone 2g/3g have only 128mb of memory, and since gnu tools aren't resident in memory there is no problem having a full compliment of them on the phone.
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Nonono, not RAM. Flash memory. iPhone has tons of it. G1 (where most of the developers got started, mind you) has very little. Further, the partitioning left limited room for additional binaries. There's some ways around that (symlinks, mostly), but they aren't elegant, and are subject to wiping at inopportune times if you aren't careful.
anethema said:
The problem with debian is it is not really a nice UI for a phone. It would just be nice to have my phone, plus having the GNU tools underneath.
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I'm curious about your use case. "It would be nice" is, well, nice, but is there a need you have that the existing tools aren't fulfilling?
anethema said:
It isn't like its a dealbreaker, it just struck me as odd that all the proper tools have been built for the iPhone, and using it really feels like a full computer you're SSHing into, where as an open source Linux based OS on android basically is lacking all of it, minus the limited functionality provided by Busybox and Dropbear (like..dropbear really?).
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I'm not sure what's with the Dropbear hate. There are not many use-cases for SSH servers on a phone, so few people have worked on it. I'd think the Android-phone-powered robot guys are the most likely to need it. But again, Dropbear is going to perform a whole heck of a lot better on a G1 than OpenSSH, and the G1 is the origin of all this stuff.
Remember, Android is explicitly not GNU/Linux. You might call it "Android/Linux." The fact that the Android userspace is open-source means that the alternate (and exciting new) userspace is attracting development, instead of people trying to port GNU just so they can use their closed-source iPhone. This is, in fact, a Good Thing, because it can result in improvements for all Android users (via contributions to AOSP), not just that subset of geeks (read: us) who mod their phones.
Understanding this difference is key to understanding the development pattern. People aren't working on the GNU userspace for Android phones because the Android userspace supplants it. The tools we have do what is needed, nothing more. In fact, `am' and `pm' are more useful in the Android context than anything that's left out of Busybox.
anethema said:
These things have more memory and comparable processing speed to computers running windows 98 and early XP, so there is no reason not to have everything available to you when you need it.
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Back to my use case comment above. What is it that you need?
anethema said:
Thanks for your reply!
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No problem, it's a good discussion.
I guess it is basically that you don't know what you need until you need it. I treat my phones like this basically like little computers. Certainly on a laptop/desktop no one would bother questioning why you need general tools you use to get jobs done.
For the iPhone there was a need for unique certification to apples push servers so phones that were basically 'tricked' into activating could still get push messages via these servers.
I wrote a tool called Push Doctor with phone based scripts and with a donor style one server side. Basically I was generating these certificates and people could download them. The whole thing on both side is just a bunch of shell scripts. One running on the phone, one on my and cert donors computers. Now this may or may not have worked in busybox as I haven't tested it, but I just mean you never know what you are going to use stuff for, and having a nice standard set of tools across all Linux platforms can be nice to have for this reason.
As far as the space issue, I think that whole thing seems crazy as well. You're right there is a ton of space on the iPhone, but the G1 came out after it, and the Nexus One long after it, so its too bad 'space' is still an issue these days requiring ugly hacks to circumvent.
Regardless the tools could be distributed as part of several core apk's which people could install if they wish.
Like I said above, these are hardly embedded devices anymore. It's not like there's 4kb of ram and 5 mips CPU.
As far as dropbear, it isn't that I hate it, I just think even the G1 has comparable speed to the first iPhone (not in the Graphics/UI but certainly as far as the CPU is concerned) and running something as insignificant as OpenSSH should not be an issue. I've never personally heard of dropbear, and have no idea what their security track record is, but I do know OpenSSH's. It is a VERY widely used package with a lot of eyes on it making sure it is doing what it is supposed to be doing.
Apparently the default dropbear will authenticate any password if you enable passwords and you have to build your own from source run about 50 commands, all to get it going.
Where is the APK for a working dropbear, or apt-get install dropbear? Can you even have APK's for system level packages? Everything I seem to find tends to be a custom download from someones site whcih you have to 'push' to your phone, try to follow some 50 step guide to hopefully get going, etc.
I am loving a lot of facets of this OS, I'm just curious where the community is to work on this stuff, get it going, and make it easy. Android isn't really -that- young.
anethema said:
For the iPhone there was a need for unique certification to apples push servers so phones that were basically 'tricked' into activating could still get push messages via these servers.
I wrote a tool called Push Doctor with phone based scripts and with a donor style one server side. Basically I was generating these certificates and people could download them. The whole thing on both side is just a bunch of shell scripts. One running on the phone, one on my and cert donors computers. Now this may or may not have worked in busybox as I haven't tested it, but I just mean you never know what you are going to use stuff for, and having a nice standard set of tools across all Linux platforms can be nice to have for this reason.
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Market Enabler is in that class of application, and, like other "rooted" apps relies on shell calls to Busybox on the backend--ugly, but keep in mind this is an attempt to explicitly defeat the Android security model. BB is sufficiently standard and POSIX conformant that it hasn't posed any difficulties for these kinds of applications.
anethema said:
Where is the APK for a working dropbear, or apt-get install dropbear? Can you even have APK's for system level packages? Everything I seem to find tends to be a custom download from someones site whcih you have to 'push' to your phone, try to follow some 50 step guide to hopefully get going, etc.
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So-called "native"--that is, ARM binary--applications aren't supported by the Android platform in the conventional way. In mid-2009, Google released the Android NDK which permits ARM binary libraries to be intermingled with Android applications via JNI. Since Android is explicitly intended to be compile-once, run-anywhere (which is why apps run on a VM), this is only recommended for computation-heavy code. However, the Mozilla project is using the NDK to directly port legacy code (Firefox/Fennec) with a thin Java interface to the Android system, so such a thing is possible.
This doesn't really make sense for the GNU toolkit, though. The SSH case; you could certainly set up an SSH server to run as a system service using NDK+JNI to connect any SSH library you like. The fact that this has not happened leads me to believe that there is little demand.
In general, the needs of existing developers appear to be met by the tools available.
Based on everything you've mentioned--you may want to take a look at the Android Scripting Environment.
I'm undertaking a stupid project and would like to ask some questions of some more experienced developers. Yes I know there's no practical reason for this, and no you cannot talk me out of it.
I would like to create a sort of "super nerd" adaptation of CyanogenMod for command line Linux junkies, or at least for Comp Sci grad students like myself. I want my phone to be able to recompile and reinstall nearly everything it runs. Yes I know that's a painful and slow operation: I did "emerge tightvnc" on a chroot Gentoo install and the command took about 18 hours. I remain undeterred.
Questions:
Sun JDK is apparently not available for arm7a. Am I reading the docs correctly, and one can indeed use Apache Ant to compile Android? Or is Ant not what I think it is? I'm not opposed to creating a small Bochs VM that boots, mounts a network filesystem, executes some JDK task, and then signals to terminate. I'd rather not if I can help it though.
How much access does the radio hardware get to the rest of the system? If I were to store something personal in an encrypted loopback partition, could someone abuse direct memory access to read from memory without the host OS knowing about it?
Has anyone played with adapting the Android boot process to use System V type init scripts? I'd like to make it easy for Tasker to say "we're running out of memory -- go from init level 5 to something arbitrary, say 7, which stops some services. Oops, still low, go init level 8, which disables more services.
I definitely plan on sharing my work. What do you guys think of the name CyanoGentoo?
Thanks all.
Apparently Apache Ant is not what I thought it is.
How about this then: does anyone know where I might find a community for people interested in general purpose computing on an Android phone?
Michael Spencer said:
Apparently Apache Ant is not what I thought it is.
How about this then: does anyone know where I might find a community for people interested in general purpose computing on an Android phone?
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Don't know if you're still around but I'm very interested in helping and believe I may already have some solutions for you. If you're still running chroot or another form of ARM Linux distro (Debian based is what I'm coding for at the moment) then check my github
https://github.com/S0AndS0/Debian-Kit-Mods
The readme file has directions on how to clone and run the main modding script which curently has at least one if not two options that'll peek your interest for sure.
One set of options will download and install Java's JDK (either hard float or soft float) and another will download and install jMonkey (a user friendly programing SDK built on eclips) which will get you one step closer to compiling things on an Android device for Android devices. However, I've yet to crack running "Android SDK" because they have yet to reliece an ARM compatible source and "wine" (a Linux package for emulating other CPU's) is still under heavy development, so building Android from source and such is still out of the scope of what I've been able to script up for easy use.
On a side note; a quick google search of my user name and the key words guide, linux, jdk, arm and xda will result in links of what I've written up on enteracting with Linux on Android if you get stuck anywhere.
And if you search "raspberry pi android adb similar:xda" you'll find what I'll likely be working on bringing to Android; after debugging the script I'm working on to set up a Brendle (one of many methods of "cloud computing" availible for ARM) node/network through all availible network interfaces (bluetooth, 3G/4G, wifi) on Android.
Sent from my SPH-D700 using xda app-developers app
I am still around, and when I get a chance I'll take a look. I think I'm mostly satisfied with AIDE and chroot Ubuntu.
And those worried about dma exploits via radio hardware need only use a wifi-only device with a portable hotspot, I've concluded. No way to prevent these exploits otherwise.
Thanks again.
Michael Spencer said:
I am still around, and when I get a chance I'll take a look. I think I'm mostly satisfied with AIDE and chroot Ubuntu.
And those worried about dma exploits via radio hardware need only use a wifi-only device with a portable hotspot, I've concluded. No way to prevent these exploits otherwise.
Thanks again.
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Indeed AIDE has been a fantastic tool for me as well.
Heh dma was indeed a concern of mine among other security issues with running Linux over 3/4G but its to bad there's no solution yet. I'm using old phones and tablets for most tests but try as I might I can't break into them from out side my hotspot network... even though I can connect to the divice running the hotspot remotely if it is running Linux too.
hmm, I'm working on a new script of examples for networking now, lots of building blocks to my latest project, which may help new scripters with some networking tedium of finding and assigning specific IP's to variables so they can be shared or saved or modified into other commands quickly. This will upon compleation will be one of the references for other scripts I'm working on for getting openstack and MPI running on multiple devices swiftly.
Speaking of MPI; the installer for Bramble on Android now works (install option 2 within for Debian Kit users) for getting that software package installed and all that is left to work on is the setup for machine files and sshkeys for multi-node quick set-up.
Two questions; seeing as how you have AIDE, perhaps you might be able to help with my other project that I'm working on? I've another github repo where I'm working to incorporate a; soft/hard float Linux installer, terminal emulator, rdp/vnc client, scripter, and forwarding of Linux GUI to a second device and/or Chromecast of a specific desktop or Linux window with x11... Currently stuck on the terminal but still very new to Java for Android.
or because that's a bit much to ask; perhaps some help with Android scripting for installing Linux on Android that uses Debian Kit's methods to provide hard float or soft float?
I'll be around and have modified my sig for easier tracking and will be pushing more updates to github today, hopefully by the end of the day have a sshkey passer script for quickly setting up passwordless remote login. After that will be some work on setting up bridges between USB, Bluetooth, Wifi, and any other network interface available for faster transfer of large data sets.
Edit 03192014
Michael Spencer said:
Has anyone played with adapting the Android boot process to use System V type init scripts? I'd like to make it easy for Tasker to say "we're running out of memory -- go from init level 5 to something arbitrary, say 7, which stops some services. Oops, still low, go init level 8, which disables more services.
Click to expand...
Click to collapse
Check out the Debian Kit app, from what I have found it exposes all of the Linux processes and file system to Android and if running as root user on Linux then the full Android file system is exposed too. Debian Kit doesn't use chroot to run Linux so it's "possible" to run a chroot environment at the same time. And running "ps" commands on Android or Linux terminals, produce nearly identical output, of both Linux and Android processes happily running meaning that if Tasker can't see these processes then a script can run the "ps" command and run a command to shut down Linux processes; likely it's a bit more complex because re-starting those services or even suspending some could cause un-wanted behavior. Still though with testing and time it is possible to have the memory better managed.
Update 03312014- Back on making your phone compile itself subject; I'm working on using(/scripting an installer for) OpenStack on Android, which has QEMU for emulating CPU processors which will eventually allow us to install Android SDK on Android(s) running Linux. I'm using OpenStack because to emulate a normal PC processor one even a quad core ARM processor is really slow (use to be an app for this called Limbo PC emulator but last I searched the market place this app was gone) so using OpenStack will allow us to throw what ever extra Android phones into a pool of sharable CPU power; essentially I'll be creating a 7 or 8 (virtual) core processor out of networked Android phones and then emulate a 2 or 4 core x86 processor within and install the tool kits for android that have CPU requirements.
I've other plans for OpenStack too but those will require that I incorporate mesh networking and google translate. So that users anywhere can build a cloud of shared processing power.
Sent from: SPH-D700 or myTouch3Gs or Sero 7 Pro
Linux Install guide for Android devices that I'm writing:
http://forum.xda-developers.com/showthread.php?t=2240397
Or
https://docs.google.com/document/d/1ssVeIhdBuuy8CtpBP1lWgUkG6fR6oHxP20ToYPPw6zI/edit?usp=drive_web
And my script pack for installing; Java's JDK, node.js and more to your Linux OS
https://github.com/S0AndS0/Debian-Kit-Mods
Note: if you're new to Linux/scripting/command line; check readme file for instructions.
http://www.timelesssky.com/blog/building-android-sdk-build-tools-aapt-for-debian-arm
http://www.timelesssky.com/blog/develop-app-on-android-with-android-sdk
Hey all found the ^answer^ if you've not already found this blog then you all are in for a treat dig around on that above site and you'll find some other really cool stuff for Linux Android systems.
Sent from: SPH-D700 or myTouch3Gs or Sero 7 Pro
Linux Install guide for Android devices that I'm writing:
http://forum.xda-developers.com/showthread.php?t=2240397
Or
https://docs.google.com/document/d/1ssVeIhdBuuy8CtpBP1lWgUkG6fR6oHxP20ToYPPw6zI/edit?usp=drive_web
And my script pack for installing; Java's JDK, node.js and more to your Linux OS
https://github.com/S0AndS0/Debian-Kit-Mods
Note: if you're new to Linux/scripting/command line; check readme file for instructions.
Since the Moto X and other recent Droids are available for root now, I'm wondering: will hackers be able to modify Touchless Control settings? Or is that a closed source part of Android that no one can touch except for Motorola?
Or at least, will we be able to write code that's specifically for the context and voice processors that are unique to the new Motorola phones?
I've never hacked around with Android ROMs but it seems to me that the addition of these processors could mean a playground with a lot of potential to hackers. Wouldn't mind taking a stab at it myself
It likely won't be possible. The best we may get is to at least be able to take the custom touchless binaries and compile them into a custom ROM so that we get all the benefits of stock x8 functions in custom ROMs. But I doubtthat code will be released fforttweaking. Compile the binaries is the most I'd expect which is enough for me, but we may not even get that.
Reposting from where I previously put this, on the suggestion that folks here might have more idea what I am talking about.
Yes, this is a question but I couldn't see that it fit in better to one of the other forums. If I am wrong please accept my apologies and redirect me, thanks.
I'm trying to work with a custom build of Android based on KitKat to incorporate a stylus, copying some of the functionality (though not code) from Samsung which sells Android-with-stylus builds for e.g. the Note 3. I'm not including details of the specific device because right now I am working on a custom dev device and my aim is to write code which is generic enough to be usable from any Android (based on KitKat). The build (written by others) already incorporates drivers and sends stylus events correctly as motion events etc. Programming at the app level I can receive onHover, onTouch, onClick etc
The specific functionality I am trying to achieve is to pick up a stylus-button-click while hovering. It's perfectly possible to do this in any app, using an onGenericMotion Listener.
However, I want to make my "stylus-action" have system-wide effect - so that anywhere (in any other app, or in the launcher or whatever) I will pick up the event (prior to any other app) and bring up my custom menu. (just like AirCommand in Samsung Note 3) I guess in my custom Android this would then make that particular action somewhat protected or unusable for other users, but I'm ok with that.
In older Android (prior to ICS) you could try something by putting up a System Overlay (i.e in regular app code, without hacking the ROM at all), but this is no longer possible.
This is not an attempt to tapjack or whatever, I understand why this functionality has been removed from the domain of the regular programmer, and I don't want to regress my ROM back to pre-ICS behaviour by allowing the System Overlay hack. Now I am programming the system (if my change is good enough I'd like to submit it back to AOSP) so I would like to know the best method to address this. Since Samsung have already done this, it must be legal (using legal in the terms of "Android will allow it"), and I want to do it right.
Is it possible to write something similar to the System Overlay when you are running from a system service? Or is there a good choke-point to capture events before they are broadcast to the current running apps?
I was looking at (sorry, not allowed to post links) AndroidXRef /frameworks/base/core/java/android/view/View.java specifically in the function dispatchHoverEvent() which looks like a promising place. My naive idea is that I would place code here checking the MotionEvent to see if the button is pressed and if it is, don't call any listeners and instead call my little menu app (or broadcast a custom message, or something anyway). However, I've never written code on the ROM level before (LOTS of experience writing app code) so I don't know if this is a really bad point or a good point to add in code. Should I be putting things at a higher level or a lower one? Will this capture all events or not? Is it all just trial and error?
If this is the wrong place to ask questions like this, please tell me where on XDA I should be asking it. If it's the right place - please answer
Thanks
Kibi