How to build the android system

Get source

This document describes how to set up your local work environment, how to use Repo to get the Android files, and how to build the files on your machine.

Related reading:

• For an overview of the entire code-review and code-update process, see .
• For reference details about Repo, see .
  

What is in the source?

For a description of all the projects that make up the Android source code, see . To see snapshots and histories of the files available in the public Android repositories, visit the web interface.

The source is approximentely 2.1GB in size.  You will need 6GB free to complete the build.

Setting up your machine

To build the Android source files, you will need to use Linux or Mac OS. Building under Windows is not currently supported.

Linux

The Android build is routinely tested on recent
versions of Ubuntu (6.06 and later), but reports
of successes or failures on other distributions
are welcome.

Ubuntu Linux (32-bit x86)

To set up your Linux development environment, make sure you have the following:

• Required Packages:
  • Git 1.5.4 or newer and the GNU Privacy Guard.
    

• JDK 5.0, update 12 or higher.  Java 6 is not supported, because of incompatibilities with @Override.
  

• flex, bison, gperf, libsdl-dev, libesd0-dev, libwxgtk2.6-dev (optional), build-essential, zip, curl.  

$ sudo apt-get install git-core gnupg sun-java5-jdk flex bison gperf libsdl-dev libesd0-dev libwxgtk2.6-dev build-essential zip curl libncurses5-dev zlib1g-dev

• You might also want Valgrind, a tool that will help you find memory leaks, stack corruption, array bounds overflows, etc. 

$ sudo apt-get install valgrind

• Intrepid (8.10) users may need a newer version of libreadline:

$ sudo apt-get install lib32readline5-dev

Ubuntu Linux (64-bit x86)

This has not been as well tested. Please send success or failure reports to [e-mail].

The Android build requires a 32-bit build environment as well as some other tools:

• Required Packages:
  • Git, JDK, flex, and the other packages as listed above in the i386 instructions: 
    
  • JDK 5.0, update 12 or higher.  Java 6 is not supported, because of incompatibilities with @Override.
  • Pieces from the 32-bit cross-building environment
  • X11 development
    

$ sudo apt-get install git-core gnupg flex bison gperf build-essential zip curl sun-java5-jdk zlib1g-dev gcc-multilib g++-multilib libc6-dev-i386 lib32ncurses5-dev ia32-libs x11proto-core-dev libx11-dev lib32readline5-dev

• Set the system to use the right version of java by default:
  
  $ sudo update-java-alternatives -s java-1.5.0-sun
  

• X11: Ubuntu doesn't have packages for the X11 libraries, but that can be worked around with the following command:
  
  $ sudo ln -s /usr/lib32/libX11.so.6 /usr/lib32/libX11.so
  
  

Running Linux in a virtual machine

If you are running Linux in a virtual machine, you will need at least 1.5GB of RAM and 10GB or more of disk space in order to build the Android tree.

Other Linux

There's no reason why Android cannot be built on

non-Ubuntu systems. Please send any success or

failure reports to [e-mail]. In
general you will need:

• Python 2.4, which you can 
• JDK 5.0, update 12 or higher, which you can . Java 6 is not supported, because of incompatibilities with @Override.
• Git 1.5.4 or newer. You can find it at  

Anything missing from this list? Please let us know!

Mac OS

Requirements:

• To build the Android files in a Mac OS environment, you need an Intel/x86 machine. The Android build system and tools do not support the obsolete PowerPC architecture.
• Android must be built on a case-sensitive file system.
  
  • We recommend that you build Android on a partition that has been formatted with the "Case-sensitive Journaled HFS+" file system:
    • A case-sensitive file system is required because the sources contain files that differ only in case.
    • Journaled systems are more robust. (This is optional, but recommended.)
    • HFS+ is required to successfully build Mac OS applications such as the Android Emulator for OS X.
  • If you want to avoid partitioning/formatting your hard drive, you can use a case-sensitive disk image instead.
    • To create the image:
      
      • launch /Applications/Utilities/Disk Utility
      • select "New Image"
      • size: 8 GB (this will work, but you can choose more if you want to)
      • volume format: case sensitive, journaled
    • This will create a .dmg file which, once mounted, acts as a drive with the required formatting for Android development. For a disk image named "android.dmg" stored in your home directory, you can add the following to your ~/.bash_profile to mount the image when you execute "mountAndroid":
      
      
      # command to mount the android file image
      function mountAndroid  { hdiutil attach ~/android.dmg  -mountpoint /Volumes/android; }
      
      
      Once mounted, you'll do all your work in the "android" volume. You can eject it (unmount it) just like you would with an external drive.

To set up your Mac OS development environment, follow these steps:

1. Install the XCode version 2.4 or later from http://developer.apple.com/ We recommend version 3.0 or newer.
   
2. Install MacPorts. To do this:
   1. Download the tar file from and untar the files.
   2. Run the following:
        $ ./configure
        $ make
        $ sudo make install
   3. Make sure that /opt/local/bin is in your path before /usr/bin. by running
          $ echo $PATH
      If you don't see /opt/local/bin, edit $HOME/.bash_profile and add the line
        export PATH=/opt/local/bin:$PATH
      (or the equivalent for other shells) after any other PATH-related lines. To verify that your path is now correct, open a new terminal and run echo $PATH again.
   4. Ask MacPorts to update itself:
        $ sudo port selfupdate
      
3. Get the following packages from port:
     $ POSIXLY_CORRECT=1 sudo port install gmake libsdl git-core gnupg
4. Upgrade GNU make to 3.81 or later by running.  Mac OS doesn't come with a recent enough version.
     $ sudo ln -s gmake /opt/local/bin/make
   
5. Set an appropriate per-process file descriptor limit. To do this, add the following lines to your .bash_profile file:
      # set the number of open files to be 1024
      ulimit -S -n 1024

Installing Repo

Repo is a tool that makes it easier to work with Git in the context of Android. For more information about Repo, see .

To install, initialize, and configure Repo, follow these steps:

1. Make sure you have a ~/bin directory in your home directory, and check to be sure that this bin directory is in your path:
     $ cd ~
     $ mkdir bin
     $ echo $PATH
   
2. Download the repo script and make sure it is executable:
   $ curl >~/bin/repo
   $ chmod a+x ~/bin/repo

Initializing a Repo client

1. Create an empty directory to hold your working files:
   $ mkdir mydroid
   $ cd mydroid
   
2. Run repo init to bring down the latest version of Repo with all its most recent bug fixes. You must specify a URL for the manifest:
   $ repo init -u git://android.git.kernel.org/platform/manifest.git
   • If you would like to check out a branch other than "master", specify it with -b, like:
     $ repo init -u git://android.git.kernel.org/platform/manifest.git -b cupcake
     
3. When prompted, configure Repo with your real name and email address. If you plan to submit code, use an email address that is associated with a .
   

A successful initialization will end with a message such as
   repo initialized in /mydroid

Your client directory should now contain a .repo directory where files such as the manifest will be kept.

What will my name and email be used for? 

To use the Gerrit code-review tool, you will need an email address that is connected with a (which does not have to be a Gmail address). Make sure this is a live address at which you can receive messages. The real name that you provide here will show up in attributions for your code submissions.

What is a manifest file?

The Android source files are divided among a number of different repositories. A manifest file contains a mapping of where the files from these repositories will be placed within your working directory when you synchronize your files.

Getting the files

To pull down files to your working directory from the repositories as specified in the default manifest, run

   $ repo sync 

For more about repo sync and other Repo commands, see .

The Android source files will be located in your working directory under their names.

Building the code

To build the files, run make from within your working directory:
    $ cd ~/mydroid 
    $ make

If your build fails, complaining about a missing "run-java-tool", try setting the ANDROID_JAVA_HOME env var to $JAVA_HOME before making.  E.g.,

    $ export ANDROID_JAVA_HOME=$JAVA_HOME

Using an IDE

• for Android platform development
  

Troubleshooting

ImportError: No module named readline

Mac users getting this should install Python 2.5.2.  

Linux users that installed Python from source, make sure the dependencies for libreadline are installed, and rebuild Python.

What is next?

To learn about reporting an issue and searching previously reported issues, see . For information about editing the files and uploading changes to the code-review server, see .