Database Develop

[Q] Android development

Let's say that I wanted to get into android rom development, what would be a good place to start to learn. I've downloaded several e-books about android development, but they all pertain to writing applications for android OS, not really getting into modding the OS itself. I suspect I'd need to learn about linux then translate that knowledge to android?
Anybody have any good places to start or good reference materials?
It appears that none of the cyanogenmod team is even going to do anything with the Captivate, they're all working on I9000 and Vibrant, totally ignoring the Captivate. So, I thought I'd get in there and try and learn.

Building Android from source - their own site is the best for instructions on how to build android: http://source.android.com/
Building Captivate requires downloading the sources, building the kernel using the build_kernel.sh after you've fixed the toolchain paths. Or you can just use the usual linux kernel building method that the script actually does underneath.
Then you need to build eclair (or froyo). Samsung has opensourced most of the code but not all so you need to figure out how to merge vanilla eclair source into Samsung's tree, and build it. There is a readme in the source from Samsung about what to change in the build files.
You're going to be doing a lot of googling . . . I haven't figured out all the details of the Samsung eclair build so you're on your own there. Maybe others can chime in.
-Atin

atinm said:
Building Android from source - their own site is the best for instructions on how to build android: http://source.android.com/
Building Captivate requires downloading the sources, building the kernel using the build_kernel.sh after you've fixed the toolchain paths. Or you can just use the usual linux kernel building method that the script actually does underneath.
Then you need to build eclair (or froyo). Samsung has opensourced most of the code but not all so you need to figure out how to merge vanilla eclair source into Samsung's tree, and build it. There is a readme in the source from Samsung about what to change in the build files.
You're going to be doing a lot of googling . . . I haven't figured out all the details of the Samsung eclair build so you're on your own there. Maybe others can chime in.
-Atin
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Thanks. Thats what I'm talking about, a lot of what you said seems Greek to me. I'd like to learn how to do all that. I guess, just read a lot from the google source website?

My advice would be to first learn how to go muck in the linux kernel and the Android sources in general. The Captivate code has been hacked some by Samsung so it doesn't quite follow all the rules about where files are supposed to go (there is no vendor tree for example) but at least it is a start. The google source site is the best for instructions on how to do vanilla stuff that's not hardware specific. Google around for more specific instructions related to the particular problem you are trying to solve after that.
Building working stuff at this level isn't easy. Unless you are somewhat experienced or willing to spend a lot of time learning and making mistakes, I'd say leave this to people who have some experience at this level and come back to it when building for the Captivate is well understood and the knowledge has been distributed enough so lots of people can help you when you have specific questions (no one likes answering general "how to" stuff on a device specific thread).
-Atin

[Q] Is gingerbread(Android 2.3) coming to the Galaxy S I9000?

Roms based on froyo or gingerbread?
The discussion in the thread "30/Jun r1 (JFB) - MoDaCo Custom ROM for Samsung Galaxy S with Online Kitchen" is a bit confusing so I thought it best to make it a new topic to get it straight.
Will it be possible to make roms based on froyo, gingerbread or any other coming android version, before Samsung makes an update? As I understand psychoace it will be ”near impossible to get roms from other sources like Sense roms or Froyo”. Others are not so sure.
This is important as Samsung is known for its lack of interest in OS updates. Who knows if they will take gingerbread to GS? If they won't can it be done by the really smart guys?

I don't think even HTC will update there top line to V3 (ginger bread). Froyo is coming any way to GS in near future. Now ginger bread should be possible too as GS is power full enough to run. When? we should wait and see. Nexus just got updated to 2.2.
Will see how things go in future.

Samsung has released there kernel sources and there software sources. I haven't had a chance to look in to it deeply but if it has the code of the drivers etc.. it should be possible to merge (with some work obviously) sources and to compile froyo.

kimatrix said:
Samsung has released there kernel sources and there software sources. I haven't had a chance to look in to it deeply but if it has the code of the drivers etc.. it should be possible to merge (with some work obviously) sources and to compile froyo.
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But don't those drivers only work with 2.1 and just simply won't with any version higher unless samsung releases new source and drivers for 2.2 and then 3.0. So if say samsung never releases anything any source/drivers that work with 3.0 then you would be out of luck to actually get everything to work.

MrDSL said:
But don't those drivers only work with 2.1 and just simply won't with any version higher unless samsung releases new source and drivers for 2.2 and then 3.0. So if say samsung never releases anything any source/drivers that work with 3.0 then you would be out of luck to actually get everything to work.
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That is true but if you have the full sources you are able to look what the differences are and maybe patch those by your self. Assume a wlan driver is using an function that has changed or is gone in 2.2, then you can try to patch that by finding the new one for it to work with. If you don't have the sources it's much harder to do those kind of things.
As I sad you have the sources so you can play by your self even if samsung does not do anything. It does not mean it's easy and it does not mean it can be done fast. But it does mean it could be done.

kimatrix said:
That is true but if you have the full sources you are able to look what the differences are and maybe patch those by your self. Assume a wlan driver is using an function that has changed or is gone in 2.2, then you can try to patch that by finding the new one for it to work with. If you don't have the sources it's much harder to do those kind of things.
As I sad you have the sources so you can play by your self even if samsung does not do anything. It does not mean it's easy and it does not mean it can be done fast. But it does mean it could be done.
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But the video drivers are already compiled. Can they be easily decompiled? It's not a source file if it's already compiled.

psychoace said:
But the video drivers are already compiled. Can they be easily decompiled? It's not a source file if it's already compiled.
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Can they be decompiled and made to work? Of course!
Will someone be motivated to do all this work? Unknown.
Besides drivers arent the only issue to getting a new version of Android on a phone. If you dont have source for any proprietary userland daemons/apps (like radio?) that communicate with the hardware you will be SOL on that as well.

MMMMMMMMM if we can do it for the G1 we can do it SGS...the question is when and how much work. The Galaxy S will be Samsung's flagship device for A YEAR so I'd hope to get Gingerbread...unless Samsung are really stupid. Especially with a lot of US launches, they'll be able to relaunch with Gingerbread as it comes is my hope.

psychoace said:
But the video drivers are already compiled. Can they be easily decompiled? It's not a source file if it's already compiled.
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Who told you that??? The source code of the GPU as well as every other coprocessor is there.
The two .o file that started this all fiasco are ok and you as long as the make file include them in the build they would work perfectly.
All they have inside is a simple elf code to tell the s3c*** to do whatever it needs to do. A source code wouldn't have been beneficial as it would have to be compiled differently for a different ARM instruction set .

kitsune223 said:
Who told you that??? The source code of the GPU as well as every other coprocessor is there.
The two .o file that started this all fiasco are ok and you as long as the make file include them in the build they would work perfectly.
All they have inside is a simple elf code to tell the s3c*** to do whatever it needs to do. A source code wouldn't have been beneficial as it would have to be compiled differently for a different ARM instruction set .
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But when you need drivers for 2.2 the source code would be optimal because these drivers are not going to work without some hacking.

They are going to work as they are non kernel bound ELF files.
Guys this isn't a driver ,if it was a kernel module ( or "driver" s you call it) it would have been a .ko file and had a slightly different structure ( use readelf on a kernel module and then on this to see the difference). So no matter what it is when can use the compiled version as it not kernel bound
From quick inspection it seems like the injection code for the s3c*** . so basically its there so the kernel could reference to it when the code tells it to do so . So Basicly all we have to do is put it in the proper place when building the kerne.
So please DON'T PANIC

well the TP2 just got 2.2 FroYo (2.1 has more working drivers ATM).. but if we have it, how would it be different for the SGS to get FroYo?

You need to remember that while other companies can update kernel quite easily ( all the work is done for them by the chip manufacturer and some member of the community ) this isn't possible here as this is a chip only used in one android/other linux platform device and the company making the device also make the chip.
So give them a few weeks to work on it

J-Hop2o6 said:
well the TP2 just got 2.2 FroYo (2.1 has more working drivers ATM).. but if we have it, how would it be different for the SGS to get FroYo?
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let's just say it will be the first time a non Samsung Rom has worked on a Samsung Android phone.

psychoace said:
let's just say it will be the first time a non Samsung Rom has worked on a Samsung Android phone.
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Not true.
Look here: http://forum.samdroid.net/f28/lkmod-v-2-5-1-based-jce-en-upd-03-30-a-336/
I see a custom ROM made for the i5700
Everything is possible.

clubtech said:
Not true.
Look here: http://forum.samdroid.net/f28/lkmod-v-2-5-1-based-jce-en-upd-03-30-a-336/
I see a custom ROM made for the i5700
Everything is possible.
Click to expand...
Click to collapse
Did I say custom rom? No i said specifically non samsung based roms on a samsung device. That custom rom is based off of a Samsung rom.

This is the closest we have got to a Hero rom on a Samsung device.
http://androidforums.com/all-things-root-behold-2/60408-port-htc-hero-behold-2-wip.html
He couldn't get Rosie to boot so who knows what other problems he would of had after that (from the picture you can see he never got any network connection)
So there don't say I didn't give you any hope.

Froyo is offical. That's good, but we need to be looking past it to Gingerbread.
Froyo is announcedm confirmed, and now dated for the end of September, and that's great. But to me, that's not the question we need to be asking Samsung anymore, we need to be thinking past that.
The question people need to be asking Samsung, so we can get them on the record committed to it now, is will you release a Gingerbread update for the phone as long as the hardware is capable of supporting it. The OS is only 2-3 months from being unveiled if Google sticks to their time table, and if the rumors are true it'll be a much bigger overhaul than 2.1-2.2 is.
So unless we want our phones to be outdated before the end of the year, we need to start making a push as a community to get a commitment from Samsung to support not just the OS that was released 4 months ago, but also the much bigger one that's right around the corner.

2.2 is good.. proves everyone wrong who said "ooh its Samsung, of course they won't release Froyo."
but somehow, I doubt that samsung will somehow not upgrade SGS to 3.0. If they do, it might be a few months (at least) after everyone else gets it. The reason is, they could have new flagship devices out that they wanna push to the mass-markets, so putting gingerbread on that will boost the sales.
However, considering that they marketed the SGS so well, and have it well on its way, they might just put gingerbread on it
seriously, i see ads for SGS EVERYWHERE online.

mjgunn said:
[....]
So unless we want our phones to be outdated before the end of the year
[....]
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I totally expect that my phone will be outdated by then. That's a consequence of the world we live in But then again, i'm a nihilist

[Q] How to get started making captivate roms

Hey Guys,
I'm a developer for a living, and I'm interested in possibly working on a custom rom for my captivate. I was doing some research on how to get started, but the stuff I found was for HTC phones and involved using a starter that only works for HTC stuff.
Where can I go to find information on doing this? I'm largely interested in trying to port gingerbread, but my understanding was that until we have the full source this wasn't really possible (at least for something actually useable on a daily basis). I see supercurio is working on gingerbread, so information specific to this would be really helpful.
Thanks guys, and sorry if this should have been put in the QA section, I figured it was related to development, and could possibly be a sticky if it leads to useful info.

Pretty broad question. First requirement, is obviously...learn java.
I'm not sure if there's any specific "HOW-TO CODE YOUR OWN CAPTIVATE ROM" threads anywhere; there's general information available on http://developer.android.com , but modifying ROM's depends on the device it was written for.
As far as porting gingerbread, it will be very difficult without source and will definitely require quite a bit of kernel work. For information specific on this, supercurio would be the one to ask. Of course, the IRC's are also a great place to get information.
By the way, welcome to XDA! And I commend your motivation to develop stuff for the community here.

http://forum.xda-developers.com/showthread.php?t=869614
Doc over in the I9000 forums has the above thread started. I look there.

geokhentix said:
Pretty broad question. First requirement, is obviously...learn java.
I'm not sure if there's any specific "HOW-TO CODE YOUR OWN CAPTIVATE ROM" threads anywhere; there's general information available on http://developer.android.com , but modifying ROM's depends on the device it was written for.
As far as porting gingerbread, it will be very difficult without source and will definitely require quite a bit of kernel work. For information specific on this, supercurio would be the one to ask. Of course, the IRC's are also a great place to get information.
By the way, welcome to XDA! And I commend your motivation to develop stuff for the community here.
Click to expand...
Click to collapse
Again, I am a developer for a living. I know Java, I'm not looking for coding tutorials. I'm looking for information specifically regarding the captivate.
As far as gingerbread, it sounds like what you are saying is that what people like supercurio are working on is not really gingerbread? More of a Frankenstein created with the sdk, mashing together 2.2 kernels and what has been released for 2.3?

lbbo2002 said:
http://forum.xda-developers.com/showthread.php?t=869614
Doc over in the I9000 forums has the above thread started. I look there.
Click to expand...
Click to collapse
Looking at that thread, it appears the roms being made are just edited versions of already compiled roms? Is samsung not required to post the full source of their roms?
I'm assuming the issue with starting with the original android source, is that we wouldn't have drivers for half of the hardware in the phone. Is the only choice then to load the already compiled drivers from the samsung builds into the rom?

epoplive said:
Again, I am a developer for a living. I know Java, I'm not looking for coding tutorials. I'm looking for information specifically regarding the captivate.
As far as gingerbread, it sounds like what you are saying is that what people like supercurio are working on is not really gingerbread? More of a Frankenstein created with the sdk, mashing together 2.2 kernels and what has been released for 2.3?
Click to expand...
Click to collapse
There are different levels of making ROMs IMO.
You can combine work from others and make your own ROM. This requires no coding experience. For instance, I took JH7_OTA, dropped in Atinms Voodoo 3 kernel, removed bloatware, added my own custom framework (icons), etc., signed it and flashed it.
Then there is the whole Kernel side of things that requires an entire development environment (Linux) and C/C++ programming skills. I'm trying to get to this point. You can start by downloading the source and building it in your own environment familiarizing yourself with the codebase.

Indeed. Packing a ROM and making the contents of the ROM are two different sides of the spectrum. Even some minor framework modifications can be performed by the most tech-inept, as long as they have a good resource to work off of.
epoplive said:
Again, I am a developer for a living. I know Java, I'm not looking for coding tutorials. I'm looking for information specifically regarding the captivate.
As far as gingerbread, it sounds like what you are saying is that what people like supercurio are working on is not really gingerbread? More of a Frankenstein created with the sdk, mashing together 2.2 kernels and what has been released for 2.3?
Click to expand...
Click to collapse
I was only prodding fun when I mentioned learning Java, just to break the ice. All I'm saying is trial and error is the best way to learn Android if you're already a decent programmer. Without knowing what the source code looked like before Samsung owned it, we don't really have a base environment to work off of, which means we are modifying work that was already modified from stock; which is why it will be pretty hard to find a lot of definitive coding information about the Captivate.
Supercurio isn't making a frankenstein 2.2-2.3 hybrid. The kernel is where all of the information about your hardware resides. Supercurio needs to take the Gingerbread kernel from the Nexus S, and modify it to run with our hardware. You can't run a 2.3 ROM without a 2.3 kernel; so we CAN'T use a 2.2 kernel to run full gingerbread; and since a 2.3 kernel doesn't exist for the Captivate, he is using the Nexus s's kernel as a base, or as a reference to merge the differences between the two, creating a kernel that will support the Nexus S ROM on a phone that isn't the Nexus S.
epoplive said:
Looking at that thread, it appears the roms being made are just edited versions of already compiled roms? Is samsung not required to post the full source of their roms?
I'm assuming the issue with starting with the original android source, is that we wouldn't have drivers for half of the hardware in the phone. Is the only choice then to load the already compiled drivers from the samsung builds into the rom?
Click to expand...
Click to collapse
Correct. We don't have the source code for Froyo yet for the Captivate(or an OTA for that matter ), a lot of ROM's being made are based off of the SGS I9000 2.2 source, and because we have that source, we have a pretty much fully functional "captivated" i9000 kernel.

geokhentix said:
Indeed. Packing a ROM and making the contents of the ROM are two different sides of the spectrum. Even some minor framework modifications can be performed by the most tech-inept, as long as they have a good resource to work off of.
I was only prodding fun when I mentioned learning Java, just to break the ice. All I'm saying is trial and error is the best way to learn Android if you're already a decent programmer. Without knowing what the source code looked like before Samsung owned it, we don't really have a base environment to work off of, which means we are modifying work that was already modified from stock; which is why it will be pretty hard to find a lot of definitive coding information about the Captivate.
Supercurio isn't making a frankenstein 2.2-2.3 hybrid. The kernel is where all of the information about your hardware resides. Supercurio needs to take the Gingerbread kernel from the Nexus S, and modify it to run with our hardware. You can't run a 2.3 ROM without a 2.3 kernel; so we CAN'T use a 2.2 kernel to run full gingerbread; and since a 2.3 kernel doesn't exist for the Captivate, he is using the Nexus s's kernel as a base, or as a reference to merge the differences between the two, creating a kernel that will support the Nexus S ROM on a phone that isn't the Nexus S.
Correct. We don't have the source code for Froyo yet for the Captivate(or an OTA for that matter ), a lot of ROM's being made are based off of the SGS I9000 2.2 source, and because we have that source, we have a pretty much fully functional "captivated" i9000 kernel.
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Click to collapse
Ah, thanks, that's pretty much the information I was looking for.

Budding dev needs some help

Hello all. I've recently been trying to get into Android development, more specifically Kernel development. I've played around with some kitchens and looked at the GB kernel sources from Samsung and tweaked it around.
Previously I previously learned Java to a point where I can put basic lines down and also more advanced stuff but with a bit of help here and there.
I have one question though, what would be the recommended path for creating an ICS Kernel. My plan is to start of with something "stock" and build up but I'm not quite sure what to consider stock seeing as the S1 never got ICS officially. Would I have to use CM9's Kernel sources and if so where do I acquire them.
I also have a good understanding of Ubuntu and its terminal and have a functional idea of what I'm doing there.

M7 Specific Rom Building Instructions?

I've done some searching and found many dated and non-specific references on building AOSP for your device. I didn't even find anything referencing lollipop. I was wondering if somebody had written up some device specific instructions for the m7. I'm looking for information like pulling in the correct binaries and kernel source.

91ludesit said:
I've done some searching and found many dated and non-specific references on building AOSP for your device. I didn't even find anything referencing lollipop. I was wondering if somebody had written up some device specific instructions for the m7. I'm looking for information like pulling in the correct binaries and kernel source.
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Which ROM are you looking for? I found the instructions for building CyanogenMod for the Nexus 6 to be helpful when I rebuilt CM7 for the original Droid Incredible. I don't see any reason it can't be extended to the M7 and lollipop--I can indicate the appropriate changes, if that's helpful.
wiki.cyanogenmod.org/w/Build_for_shamu

I'm just wanting to build straight from aosp with maybe a custom kernel source.

91ludesit said:
I'm just wanting to build straight from aosp with maybe a custom kernel source.
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Ah. Well, I'm not an expert by any means, but I don't think it's quite that straightforward. The Android source released by Google has no support for any devices except Nexus devices. Various ROMs, CyanogenMod being the biggest, have created open-source device trees to support additional devices. In the source tree for the device that I built for (Droid Incredible), for example, there is code for "liblights", "libsensors", a kernel module, some firmware, some configuration tweaks for various system apps like Camera and Torch--and a configuration file for the kernel. So if you want to compile AOSP for your m7, you'll have to port all that code over to the AOSP tree.
You might find it valuable to try building CM12 for your device. If you can do that successfully, then you can start tweaking with the kernel config that CM provides to suit your needs. Building CM is also very well documented, and once you've done that, it's more clear how you'd go about trying to build AOSP, and you can use the stuff that CM has done to help you port to AOSP if you want.
Here's Google's information on building straight AOSP:
https://source.android.com/source/building-devices.html
Here are CyanogenMod's guides on building for m7 and tweaking the kernel config:
http://wiki.cyanogenmod.org/w/Build_for_m7
http://wiki.cyanogenmod.org/w/Doc:_integrated_kernel_building
Here is an XDA Developer guide to porting a device from one AOSP-based ROM to another:
http://xda-university.com/as-a-developer/porting-aosp-roms-using-source-code

Thanks for the info, that's what I was afraid of. I was wanting to build something like the Google play edition, but with all the latest security updates.