commit | ca163edec1a5585b697067c8a9994d4fb9b18caa | [log] [tgz] |
---|---|---|
author | Anton Hansson <hansson@google.com> | Tue Sep 27 22:06:11 2022 +0000 |
committer | Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com> | Tue Sep 27 22:06:11 2022 +0000 |
tree | d8a5549526cee79c5954798e63c8a28e462da5de | |
parent | 1d2ab45f79ce7c74a2e118353bb6a20374d2ed12 [diff] | |
parent | 2c6e2c9af0e37744bfe541105050071b9948ee4b [diff] |
[automerger skipped] DO NOT MERGE Allow extension version 4 am: eb9ac9a214 -s ours am: 2c6e2c9af0 -s ours am skip reason: subject contains skip directive Original change: https://android-review.googlesource.com/c/platform/packages/modules/SdkExtensions/+/2231690 Change-Id: I22b119d035b3cf5eecb75108d11900fd74a002f8 Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
SdkExtensions module is responsible for:
The module is packaged in an apex, com.android.sdkext
, and has several components:
bin/derive_classpath
: a native binary that runs early in the device boot process. It reads individual classpath configs files from the system and other modules, merges them, and defines the definition of *CLASSPATH environ variables.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.derive_sdk
is a program that reads metadata stored in other apex modules, in the form of binary protobuf files in subpath etc/sdkinfo.pb
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.
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)
.
derive_classpath
service reads and merges individual config files in the /system/etc/classpaths/
and /apex/*/etc/classpaths
. Each config stores protobuf message from classpaths.proto
in a proto binary format. Exact merging algorithm that determines the order of the classpath entries is described in derive_classpath.cpp
and may change over time.
An extension is a way to group a set of modules so that they are versioned together. We currently define a new extension for every Android SDK level that introduces new modules. Every module shipped in previous versions are also part of the new extension. For example, all the R modules are part of both the R extensions and the S extensions.
The steps to define a new extension are:
derive_sdk.cpp
by:GetSdkLevel
with the new enum setderive_sdk_test.cpp
verifying the new extensions workSdkExtensions.getExtensionVersion
API support the new extensions.