| commit | 30e7c30da3f2ff3433093a24df3b6f0e2ba1b5e4 | [log] [tgz] |
|---|---|---|
| author | weisu <weisu@google.com> | Wed Feb 02 02:07:17 2022 +0000 |
| committer | weisu <weisu@google.com> | Wed Feb 02 17:04:02 2022 +0000 |
| tree | 5c48e247e933f9f0876f4fd99d2648ca834b8d6a | |
| parent | 90c6c2a8b2c24d966fb7fe7afa92815a8765d1b7 [diff] |
Write files in a temporary directory Avoid writing test files in the build output directory which fails when run with Bazel. This happens because Bazel's sandboxing environment ensures that the test's working directory is unwritable. See https://docs.bazel.build/versions/main/sandboxing.html for more information. Bug: 216204033 Test: atest --bazel-mode --host gen_sdk_test Test: atest --host gen_sdk_test Change-Id: I45e621e6dde4048ba6ec4854cbe76bc5c9c81d32
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.