tag | 0d9b47aa9ad03bfa4cd54d73eebc2518f9a897b0 | |
---|---|---|
tagger | The Android Open Source Project <initial-contribution@android.com> | Mon Aug 22 14:18:43 2022 -0700 |
object | bec0bbfcc5f8cae7608b96977e5daa2ca67135f4 |
Platform Tools Release 33.0.3 (8952118)
commit | bec0bbfcc5f8cae7608b96977e5daa2ca67135f4 | [log] [tgz] |
---|---|---|
author | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Tue Aug 16 06:38:14 2022 +0000 |
committer | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Tue Aug 16 06:38:14 2022 +0000 |
tree | adbc9fdf62051a18a9b4fde385960f7d8273724e | |
parent | 9ec4ef35ca4fb0c516f237a0f1e20d13045d9ada [diff] | |
parent | e02a16a70e533111394e512205dc9b2e59ecf9e5 [diff] |
Snap for 8952093 from e02a16a70e533111394e512205dc9b2e59ecf9e5 to sdk-release Change-Id: Ibf996e12b3a75c3fe88c093c43833ad62e795391
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.