JNA: Support GraalVM (R7) #14
Closed
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
sgammon
requested changes
Jun 13, 2024
Adds a JAR publication at `jna-graalvm.jar`, with accompanying build infrastructure, which provides support for JNA within the context of the Substrate Virtual Machine (SVM). GraalVM Native Image targets use SVM instead of JVM at runtime. JNA's current strategy of unpacking libraries at runtime works under SVM, but is suboptimal; the binary is native, so it can simply include JNA object code for the current platform directly. To accomplish this, several GraalVM "feature" implementations are provided in this new publication. By default, regular JNA access is enabled through the `JavaNativeAccess` feature; this class enables reflection and runtime JNI configurations for downstream projects which use JNA. Another feature, `SubstrateStaticJNA`, is experimental because it relies on unstable GraalVM APIs, but instead of loading JNA at runtime from a dynamic library, it builds JNA into the final native image with a static object. These features are enabled through a resource within `META-INF`, called `native-image.properties`, which is picked up by the native image compiler at build time. The new artifact only needs to be present for GraalVM native targets at build time; otherwise, the classes and libraries in `jna-graalvm.jar` are inert. Includes tested support for: - macOS aarch64 - Linux amd64 - feat: add `jna-graalvm.jar` publication - feat: add base `JavaNativeAccess` feature for auto-config of JNA - feat: add initial implementation of `SubstrateStaticJNA` feature - test: sample/test gradle build for native image - chore: ci config to run native sample - chore: add readme to `lib/gvm` Signed-off-by: Sam Gammon <[email protected]> Signed-off-by: Dario Valdespino <[email protected]> Co-authored-by: Sam Gammon <[email protected]> Co-authored-by: Dario Valdespino <[email protected]>
When operating under static linkage in SVM (Native Image), JNA's `JNI_OnLoad` hooks are not run. We need to sanity-check at the first JNI border and run static initialization manually. Additionally, `JNI_OnLoad` should be provided in static contexts as `JNI_OnLoad_jnidispatch`. This changeset fixes both issues. Signed-off-by: Sam Gammon <[email protected]> Signed-off-by: Dario Valdespino <[email protected]>
When linked statically on GraalVM, JNI symbols declared in the overloaded form cannot be resolved. Luckily, all of `Native`'s callsites are in `Pointer` or itself, and all `native` methods of `Native` are non-public. This PR adjusts the JNA C API to avoid using overloaded `read`, `write`, or `getDirectByteBuffer`. Callsites are amended in `Pointer` accordingly. Signed-off-by: Sam Gammon <[email protected]> Signed-off-by: Dario Valdespino <[email protected]>
Implements a new optional linkage feature, called Static JNI, under GraalVM Native Image. With `com.sun.jna.SubstrateStaticJNA` enabled (opt-in), JNA is loaded eagerly at image build time, and then linked against a static copy of `libjnidispatch` at image link-time. The result is that `libjnidispatch.a` is embedded within the final image. No precursor library unpacking step is necessary before using JNA in this circumstance, because JNA's native layer is built directly into the image itself. - feat: implement static jni feature - chore: full gvm ci build - chore: add static jni sample Signed-off-by: Sam Gammon <[email protected]> Signed-off-by: Dario Valdespino <[email protected]> Co-authored-by: Sam Gammon <[email protected]> Co-authored-by: Dario Valdespino <[email protected]>
sgammon
force-pushed
the
feat/static-graalvm-jni-r7
branch
from
5860cd3
to
b2e8b52
Compare
sgammon
force-pushed
the
feat/static-graalvm-jni-r7
branch
from
b2e8b52
to
7fe4da6
Compare
sgammon
approved these changes
Jun 13, 2024
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Testing for fixes against #13.