tag | be5fce5b039cf7230dcb956c77a8e4f5a660d5a8 | |
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tagger | The Android Open Source Project <initial-contribution@android.com> | Wed May 11 05:14:19 2022 +0000 |
object | a09a2f4ac5616463b8f994ef1001f655248bdb8f |
Android mainline 12.0.0 release 93
commit | a09a2f4ac5616463b8f994ef1001f655248bdb8f | [log] [tgz] |
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author | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Thu Feb 03 19:31:47 2022 +0000 |
committer | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Thu Feb 03 19:31:47 2022 +0000 |
tree | 5c48e247e933f9f0876f4fd99d2648ca834b8d6a | |
parent | d7f47b2a45a9e91cf1c2197cdf26216cda482130 [diff] | |
parent | 6a70d7df903e9f3aa1cb87a72348f532ecd74427 [diff] |
Snap for 8146118 from 6a70d7df903e9f3aa1cb87a72348f532ecd74427 to mainline-permission-release Change-Id: Icbd3bca6b7145dacfc0582c2c204485cb48a46de
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.
For every new Android SDK level a new extension version should be defined. These are the steps necessary to do that:
derive_sdk.cpp
by:GetSdkLevel
with the new enum setderive_sdk_test.cpp
verifying the new extensions worksSdkExtensions.getExtensionVersion
API support the new extensions.