Building for Emulator/AVD
Introduction
In case you don’t have an officially supported device, don’t want to test changes on your daily driver, or are just someone who wants to test apps with LineageOS-specific features, we’ve still got you covered.
These instructions will help you build an emulator-compatible version of LineageOS, ready to run on your computer. If you want to use Android Studio/AVD there are also instructions for packing up/installing your custom build instead of the default AOSP images that Google provides.
What you’ll need
- A relatively recent x86_64 computer:
- Linux, macOS, or Windows - these instructions are only tested using Ubuntu 20.04 LTS, so we recommend going with that.
- A reasonable amount of RAM (16 GB to build up to
lineage-17.1
, 32 GB or more forlineage-18.1
and up). The less RAM you have, the longer the build will take. Enabling ZRAM can be helpful. - A reasonable amount of Storage (200 GB to build up to
lineage-17.1
, 300 GB forlineage-18.1
and up). You might require more free space for enablingccache
or building for multiple devices. Using SSDs results in considerably faster build times than traditional hard drives.
- A decent internet connection and reliable electricity. :)
- Some familiarity with basic Android operation and terminology.
It may be useful to know some basic command line concepts such as
cd
, which stands for “change directory”, the concept of directory hierarchies, and that in Linux they are separated by/
, etc.
Let’s begin!
Build LineageOS
Install the platform-tools
If you haven’t previously installed adb
and fastboot
, you can download them from Google.
Extract it running:
unzip platform-tools-latest-linux.zip -d ~
Now you have to add adb
and fastboot
to your PATH. Open ~/.profile
and add the following:
# add Android SDK platform tools to path
if [ -d "$HOME/platform-tools" ] ; then
PATH="$HOME/platform-tools:$PATH"
fi
Then, run source ~/.profile
to update your environment.
Install the build packages
Several packages are needed to build LineageOS. You can install these using your distribution’s package manager.
apt-get install
command directly in the Terminal.To build LineageOS, you’ll need:
bc bison build-essential ccache curl flex g++-multilib gcc-multilib git git-lfs gnupg gperf imagemagick lib32readline-dev lib32z1-dev libelf-dev liblz4-tool libsdl1.2-dev libssl-dev libxml2 libxml2-utils lzop pngcrush rsync schedtool squashfs-tools xsltproc zip zlib1g-dev
For Ubuntu 23.10 (mantic), install libncurses5
from 23.04 (lunar) as follows:
wget http://archive.ubuntu.com/ubuntu/pool/universe/n/ncurses/libtinfo5_6.4-2_amd64.deb && sudo dpkg -i libtinfo5_6.4-2_amd64.deb && rm -f libtinfo5_6.4-2_amd64.deb
wget http://archive.ubuntu.com/ubuntu/pool/universe/n/ncurses/libncurses5_6.4-2_amd64.deb && sudo dpkg -i libncurses5_6.4-2_amd64.deb && rm -f libncurses5_6.4-2_amd64.deb
While for Ubuntu versions older than 23.10 (mantic), simply install:
lib32ncurses5-dev libncurses5 libncurses5-dev
Additionally, for Ubuntu versions older than 20.04 (focal), install also:
libwxgtk3.0-dev
While for Ubuntu versions older than 16.04 (xenial), install:
libwxgtk2.8-dev
Java
Different versions of LineageOS require different JDK (Java Development Kit) versions.
- LineageOS 18.1+: OpenJDK 11 (included in source download)
- LineageOS 16.0-17.1: OpenJDK 1.9 (included in source download)
- LineageOS 14.1-15.1: OpenJDK 1.8 (install
openjdk-8-jdk
)- NOTE: For building these versions you’ll need to remove
TLSv1
andTLSv1.1
fromjdk.tls.disabledAlgorithms
in/etc/java-8-openjdk/security/java.security
.
- NOTE: For building these versions you’ll need to remove
- LineageOS 11.0-13.0: OpenJDK 1.7 (install
openjdk-7-jdk
)*
* Ubuntu 16.04 and newer do not have OpenJDK 1.7 in the standard package repositories. See the Ask Ubuntu question “How do I install openjdk 7 on Ubuntu 16.04 or higher?”. Note that the suggestion to use PPA openjdk-r is outdated (the PPA has never updated their offering of openjdk-7-jdk, so it lacks security fixes); skip that answer even if it is the most upvoted.
Python
Different versions of LineageOS require different default Python versions.
- LineageOS 17.1+: Python 3 (install
python-is-python3
) - LineageOS 11.0-16.0: Python 2 (install
python-is-python2
)
If your default is python3
, but you’re building branch that requires python2
, there are various methods to using it, e.g. symlinking it manually or creating a virtualenv for it.
We recommend the latter:
Generate the virtualenv once using virtualenv --python=python2 ~/.lineage_venv
. Afterwards, activate it in each terminal where you need python2
as default by running ~/.lineage_venv/bin/activate
.
The path ~/.lineage_venv
can be chosen freely, this is just an example!
Create the directories
You’ll need to set up some directories in your build environment.
To create them:
mkdir -p ~/bin
mkdir -p ~/android/lineage
The ~/bin
directory will contain the git-repo tool (commonly named “repo”) and the ~/android/lineage
directory will contain the source code of LineageOS.
Install the repo
command
Enter the following to download the repo
binary and make it executable (runnable):
curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo
chmod a+x ~/bin/repo
Put the ~/bin
directory in your path of execution
In recent versions of Ubuntu, ~/bin
should already be in your PATH. You can check this by opening ~/.profile
with a text editor and verifying the following code exists (add it if it is missing):
# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/bin" ] ; then
PATH="$HOME/bin:$PATH"
fi
Then, run source ~/.profile
to update your environment.
Configure git
Given that repo
requires you to identify yourself to sync Android, run the following commands to configure your git
identity:
git config --global user.email "[email protected]"
git config --global user.name "Your Name"
Due to their size, some repos are configured for lfs
or Large File Storage
. To make sure your distribution is prepared for this, run:
git lfs install
To avoid duplicated Change-Id:
trailers in commit messages, especially when cherry-picking changes, make Change-Id:
a known trailer to git:
git config --global trailer.changeid.key "Change-Id"
Turn on caching to speed up build
Make use of ccache
if you want to speed up subsequent builds by running:
export USE_CCACHE=1
export CCACHE_EXEC=/usr/bin/ccache
and adding that line to your ~/.bashrc
file. Then, specify the maximum amount of disk space you want ccache
to use by typing this:
ccache -M 50G
where 50G
corresponds to 50GB of cache. This needs to be run once. Anywhere from 25GB-100GB will result in very noticeably increased build speeds
(for instance, a typical 1hr build time can be reduced to 20min). If you’re only building for one device, 25GB-50GB is fine. If you plan to build
for several devices that do not share the same kernel source, aim for 75GB-100GB. This space will be permanently occupied on your drive, so take this
into consideration.
You can also enable the optional ccache
compression. While this may involve a slight performance slowdown, it increases the number of files that fit in the cache. To enable it, run:
ccache -o compression=true
ccache
size can be lower (aim for approximately 20GB for one device).Initialize the LineageOS source repository
The following branches have been tested for building emulator images:
- lineage-16.0
- lineage-17.1
- lineage-18.1
- lineage-19.1
- lineage-20.0
- lineage-21.0
Enter the following to initialize the repository:
cd ~/android/lineage
repo init -u https://github.com/LineageOS/android.git -b lineage-21.0 --git-lfs
Download the source code
To start the download of the source code to your computer, type the following:
repo sync
The LineageOS manifests include a sensible default configuration for repo, which we strongly suggest you use (i.e. don’t add any options to sync).
For reference, our default values are -j 4
and -c
. The -j 4
part implies be four simultaneous threads/connections. If you experience
problems syncing, you can lower this to -j 3
or -j 2
. On the other hand, -c
makes repo to pull in only the current branch instead of all branches that are available on GitHub.
repo sync
command is used to update the latest source code from LineageOS and Google. Remember it, as you may want to
do it every few days to keep your code base fresh and up-to-date. But note, if you make any changes, running repo sync
may wipe them away!Start the build
Time to start building!
Setup the environment:
source build/envsetup.sh
Select the build target by running the following command, where <target>
is one of the entries in the table below:
breakfast <target> eng
Build targets | Supported <arch> |
||
---|---|---|---|
LineageOS 17 and below | |||
Phone | Emulator/GSI | <arch> |
arm , arm64 , x86 and x86_64 |
LineageOS 18.1 | |||
Phone | Emulator/GSI | <arch> |
arm , arm64 , x86 and x86_64 |
TV | Emulator/GSI | tv_<arch> |
arm , arm64 , x86 and x86_64 |
Automotive | Emulator/GSI | car_<arch> |
arm64 and x86_64 |
LineageOS 19 and above | |||
Phone | Emulator | sdk_phone_<arch> |
x86 and x86_64 |
Phone | GSI | gsi_<arch> |
arm , arm64 , x86 and x86_64 |
TV | Emulator | sdk_tv_<arch> |
arm and x86 |
TV | GSI | gsi_tv_<arch> |
arm , arm64 , x86 and x86_64 |
Automotive | Emulator | sdk_car_<arch> |
arm64 and x86_64 |
Automotive | GSI | gsi_car_<arch> |
arm64 and x86_64 |
LineageOS 21 and above | |||
Phone | Emulator | sdk_phone_<arch> |
arm64 and x86_64 |
Phone | GSI | gsi_<arch> |
arm , arm64 , x86 and x86_64 |
TV | Emulator | sdk_tv_<arch> |
arm and x86 |
TV | GSI | gsi_tv_<arch> |
arm , arm64 , x86 and x86_64 |
Automotive | Emulator | sdk_car_<arch> |
arm64 and x86_64 |
Automotive | GSI | gsi_car_<arch> |
arm64 and x86_64 |
For starting, x86
or x86_64
is recommended, as your computer can run it natively using hardware acceleration.
arm64
for supported LineageOS Versions.This will significanly improve the emulator performance compared to using
x86_64
builds via a translation layer such as Rosetta 2.Instead of eng
one can also target userdebug
, the latter is used by official AOSP emulator images, but ADB and communication with the emulator will need to be enabled first.
Now, build the image:
mka
Running the emulator
Assuming the build completed without errors, type the following in the terminal window the build ran in:
emulator
The emulator will fire up and you’ll see the LineageOS boot animation. After some time, it will finish booting up and be ready to use.
Success! So… what’s next?
You’ve done it! Welcome to the elite club of self-builders. You’ve built your operating system from scratch, from the ground up. You are the master/mistress of your domain… and hopefully you’ve learned a bit on the way and had some fun too.
Exporting for use in Android Studio/AVD
In case you want to run the emulator image independently from the system/terminal you built it in, you are able to export the built image into a format that can be used by Android Studio/AVD. To do that, run the following command in the same terminal that you originally started the build in:
- LineageOS 20 and below
mka sdk_addon
If you now look into the out/host/linux-x86/sdk_addon
directory, you will find a ZIP file (ending in -img.zip
) that contains all the necessary files for running the emulator image externally.
- LineageOS 21 and above
mka emu_img_zip
If you now look into the out/target/product/<arch>
directory, you will find a ZIP file sdk-repo-linux-system-images.zip
that contains all the necessary files for running the emulator image externally.
To deploy the build into your Android Studio installation, move the contained folder (which is named after the architecture that you built for) into a subfolder of /path/to/android/sdk/system-images
.
AOSP uses the following path name by default, but you are free to make up your own as well:
system-images/android-<sdk version>/<tag>/<arch>
(where <tag>
is one of default
/google_apis
/google_apis_playstore
)
LineageOS emulator builds will use the tag lineage
by default (visible as “LineageOS” in the images list).
As long as you haven’t moved the folder directly into system-images
, the emulator image should now show up in the of the lists of images when creating a new virtual Android device.
To get assistance
- #LineageOS-dev - A helpful, real-time chat room (or “channel”), on the Libera.Chat IRC network.