| commit | 8fba964abfdfd278e4ebfa0351c7120b105edee1 | [log] [tgz] |
|---|---|---|
| author | Android Build Coastguard Worker <[email protected]> | Mon Feb 14 07:55:12 2022 +0000 |
| committer | Android Build Coastguard Worker <[email protected]> | Mon Feb 14 07:55:12 2022 +0000 |
| tree | 5c48e247e933f9f0876f4fd99d2648ca834b8d6a | |
| parent | 38dd59d05ef8c99b52c7d1850991184baa75d898 [diff] | |
| parent | 6a70d7df903e9f3aa1cb87a72348f532ecd74427 [diff] |
Snap for 8180713 from 6a70d7df903e9f3aa1cb87a72348f532ecd74427 to mainline-ipsec-release Change-Id: I9abe035d7b988e6df0cdd91b8b623a9ccdc449d3
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.