Downloading the Source
IN THIS DOCUMENT
- Installing Repo
- Initializing a Repo client
- Downloading the Android Source Tree
- Using Authentication
- Troubleshooting network issues
- Using a local mirror
- Verifying Git Tags
The Android source tree is located in a Git repository hosted by Google. This document describes how to download the source tree for a specific Android code-line.
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 the Developingsection.
To install Repo:
- Make sure you have a bin/ directory in your home directory and that it is included in your path:
$ mkdir ~/bin$ PATH=~/bin:$PATH
- Download the Repo tool and ensure that it is executable:
$ curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo$ chmod a+x ~/bin/repo
For version 1.17, the SHA-1 checksum for repo is ddd79b6d5a7807e911b524cb223bc3544b661c28
For version 1.19, the SHA-1 checksum for repo is 92cbad8c880f697b58ed83e348d06619f8098e6c
For version 1.20, the SHA-1 checksum for repo is e197cb48ff4ddda4d11f23940d316e323b29671c
For version 1.21, the SHA-1 checksum for repo is b8bd1804f432ecf1bab730949c82b93b0fc5fede
Initializing a Repo client
After installing Repo, set up your client to access the Android source repository:
- Create an empty directory to hold your working files. If you‘re using MacOS, this has to be on a case-sensitive filesystem. Give it any name you like:
$ mkdir WORKING_DIRECTORY$ cd WORKING_DIRECTORY
- 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, which specifies where the various repositories included in the Android source will be placed within your working directory.$ repo init -u https://android.googlesource.com/platform/manifest
To check out a branch other than "master", specify it with -b:
$ repo init -u https://android.googlesource.com/platform/manifest -b android-4.0.1_r1
- When prompted, configure Repo with your real name and email address. To use the Gerrit code-review tool, you will need an email address that is connected with a registered Google account. Make sure this is a live address at which you can receive messages. The name that you provide here will show up in attributions for your code submissions.
A successful initialization will end with a message stating that Repo is initialized in your working directory. Your client directory should now contain a .repo
directory where files such as the manifest will be kept.
Downloading the Android Source Tree
To pull down the Android source tree to your working directory from the repositories as specified in the default manifest, run
$ repo sync
The Android source files will be located in your working directory under their project names. The initial sync operation will take an hour or more to complete. For more about repo sync
and other Repo commands, see theDeveloping section.
Using Authentication
By default, access to the Android source code is anonymous. To protect the servers against excessive usage, each IP address is associated with a quota.
When sharing an IP address with other users (e.g. when accessing the source repositories from beyond a NAT firewall), the quotas can trigger even for regular usage patterns (e.g. if many users sync new clients from the same IP address within a short period).
In that case, it is possible to use authenticated access, which then uses a separate quota for each user, regardless of the IP address.
The first step is to create a password from the password generator and to save it in ~/.netrc
according to the instructions on that page.
The second step is to force authenticated access, by using the following manifest URI:https://android.googlesource.com/a/platform/manifest
. Notice how the /a/
directory prefix triggers mandatory authentication. You can convert an existing client to use mandatory authentication with the following command:
$ repo init -u https://android.googlesource.com/a/platform/manifest
Troubleshooting network issues
When downloading from behind a proxy (which is common in some corporate environments), it might be necessary to explicitly specify the proxy that is then used by repo:
$ export HTTP_PROXY=http://<proxy_user_id>:<proxy_password>@<proxy_server>:<proxy_port>$ export HTTPS_PROXY=http://<proxy_user_id>:<proxy_password>@<proxy_server>:<proxy_port>
More rarely, Linux clients experience connectivity issues, getting stuck in the middle of downloads (typically during "Receiving objects"). It has been reported that tweaking the settings of the TCP/IP stack and using non-parallel commands can improve the situation. You need root access to modify the TCP setting:
$ sudo sysctl -w net.ipv4.tcp_window_scaling=0$ repo sync -j1
Using a local mirror
When using several clients, especially in situations where bandwidth is scarce, it is better to create a local mirror of the entire server content, and to sync clients from that mirror (which requires no network access). The download for a full mirror is smaller than the download of two clients, while containing more information.
These instructions assume that the mirror is created in /usr/local/aosp/mirror
. The first step is to create and sync the mirror itself, which uses close to 13GB of network bandwidth and a similar amount of disk space. Notice the --mirror
flag, which can only be specified when creating a new client:
$ mkdir -p /usr/local/aosp/mirror$ cd /usr/local/aosp/mirror$ repo init -u https://android.googlesource.com/mirror/manifest --mirror$ repo sync
Once the mirror is synced, new clients can be created from it. Note that it‘s important to specify an absolute path:
$ mkdir -p /usr/local/aosp/master$ cd /usr/local/aosp/master$ repo init -u /usr/local/aosp/mirror/platform/manifest.git$ repo sync
Finally, to sync a client against the server, the mirror needs to be synced against the server, then the client against the mirror:
$ cd /usr/local/aosp/mirror$ repo sync$ cd /usr/local/aosp/master$ repo sync
It‘s possible to store the mirror on a LAN server and to access it over NFS, SSH or Git. It‘s also possible to store it on a removable drive and to pass that drive around between users or between machines.
Verifying Git Tags
Load the following public key into your GnuPG key database. The key is used to sign annotated tags that represent releases.
$ gpg --import
Copy and paste the key(s) below, then enter EOF (Ctrl-D) to end the input and process the keys.
-----BEGIN PGP PUBLIC KEY BLOCK-----Version: GnuPG v1.4.2.2 (GNU/Linux) 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Wi5D-----END PGP PUBLIC KEY BLOCK-----
After importing the keys, you can verify any tag with
$ git tag -v TAG_NAME
If you haven‘t set up ccache yet, now would be a good time to do it.