Google Git
Sign in
android / platform / packages / modules / SdkExtensions / c6328fed318b2e0bf3ac04383ac0a6f65de8e225
commitc6328fed318b2e0bf3ac04383ac0a6f65de8e225[log] [tgz]
authorAnton Hansson <hansson@google.com>Wed Dec 30 11:33:31 2020 +0000
committerAnton Hansson <hansson@google.com>Thu Jan 07 12:52:59 2021 +0000
tree420cf2749a54f9362f2f68b1b3c02835b74a4398
parentc02eb52548227cb395aa6b1121ac3f7758b266da [diff]
Add support for creating new extensions sdks

Add a new action 'new_sdk' that can be used to create a new extension
sdk level with a given set of module requirements.

Also add a test that we can re-create the test database correctly.

Bug: 173188089
Test: atest gen_sdk_test
Change-Id: I91b97c9638958ff39ffb6c52470a70bad0ea6697
2 files changed
tree: 420cf2749a54f9362f2f68b1b3c02835b74a4398
  1. derive_sdk/
  2. framework/
  3. gen_sdk/
  4. proto/
  5. testing/
  6. tests/
  7. Android.bp
  8. com.android.sdkext.avbpubkey
  9. com.android.sdkext.pem
  10. com.android.sdkext.pk8
  11. com.android.sdkext.x509.pem
  12. gen_sdkinfo.py
  13. manifest.json
  14. OWNERS
  15. PREUPLOAD.cfg
  16. README.md
  17. TEST_MAPPING
README.md

SdkExtensions module

SdkExtensions is a module that decides the extension SDK level of the device, and provides APIs for applications to query the extension SDK level.

General information

Structure

The module is packaged in an apex, com.android.sdkext, and has two components:

  • bin/derive_sdk: Native binary that runs early in the device boot process and reads metadata of other modules, to set system properties relating to the extension SDK (for instance build.version.extensions.r).
  • javalib/framework-sdkextension.jar: This is a jar on the bootclasspath that exposes APIs to applications to query the extension SDK level.

Deriving extension SDK level

derive_sdk is a program that reads metadata stored in other apex modules, in the form of binary protobuf files in subpath etc/sdkinfo.binarypb inside each apex. The structure of this protobuf can be seen here. The exact steps for converting a set of metadata files to actual extension versions is likely to change over time, and should not be depended upon.

Reading extension SDK level

The module exposes a java class SdkExtensions in the package android.os.ext. The method getExtensionVersion(int) can be used to read the version of a particular sdk extension, e.g. getExtensionVersion(Build.VERSION_CODES.R).

Developer information

Adding a new extension version

For every new Android SDK level a new extension version should be defined. These are the steps necessary to do that:

  • Make derive_sdk correctly set the relevant system property for the new extensions.
  • Make the SdkExtensions.getExtensionVersion API support the new extensions.
  • Extend the CTS test to verify the above two behaviors.
  • Update RollbackManagerServiceImpl#getExtensionVersions to account for the new extension version.

TODO(b/173188089): expand this section when derive_sdk is reimplemented