[vm] Native asset relative path resolution with symlinks

This CL moves native assets resolution to the embedder.

The Dart VM looks up the asset path (for example
`['relative', 'foo.so']`) with the asset id. The embedder defines
callbacks for asset loading, and returns a handle to the dylib.
Then the VM calls the embedder again with `dlsym` to lookup the symbol.

The Dart VM & kernel compiler are responsible for the asset id to
asset path mapping. The kernel compiler compiles it into the snapshot
and the VM looks it up in the snapshot.

Relative paths are resolved relative to the isolate script uri (kernel
snapshot, jit snapshot, aot snapshot, or `dart compile exe` result).
The embedder is responsible for remembering the script uri it set when
spawning the isolate group.

This CL does not add `dlclose` or `dladdr` embedder callbacks yet.
Bug: https://github.com/dart-lang/sdk/issues/55521
Bug: https://github.com/dart-lang/sdk/issues/55966

TEST=pkg/dartdev/test/native_assets/build_test.dart
TEST=tests/ffi/native_assets/asset_relative_test.dart

Bug: https://github.com/dart-lang/sdk/issues/55410
Bug: https://github.com/dart-lang/sdk/issues/55523
Bug: https://github.com/dart-lang/sdk/issues/55207
Change-Id: I75ec4a368c5fb3d2f76b03771e796ff56bcac941
Cq-Include-Trybots: dart/try:vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-win-debug-arm64-try,vm-aot-win-debug-x64-try,vm-aot-win-debug-x64c-try,pkg-linux-debug-try,pkg-linux-release-arm64-try,pkg-mac-release-try,pkg-mac-release-arm64-try,pkg-win-release-try,pkg-win-release-arm64-try,vm-aot-asan-linux-release-x64-try,vm-asan-linux-release-x64-try,vm-aot-msan-linux-release-x64-try,vm-msan-linux-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/361881
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
14 files changed
tree: b6f66c9fd22901f03052d9b2b439f52ba0fd891a
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. docs/
  6. pkg/
  7. runtime/
  8. samples/
  9. sdk/
  10. tests/
  11. third_party/
  12. tools/
  13. utils/
  14. .clang-format
  15. .gitattributes
  16. .gitconfig
  17. .gitignore
  18. .gn
  19. .mailmap
  20. .style.yapf
  21. AUTHORS
  22. BUILD.gn
  23. CHANGELOG.md
  24. codereview.settings
  25. CONTRIBUTING.md
  26. DEPS
  27. LICENSE
  28. OWNERS
  29. PATENT_GRANT
  30. PRESUBMIT.py
  31. README.dart-sdk
  32. README.md
  33. sdk.code-workspace
  34. sdk_args.gni
  35. sdk_packages.yaml
  36. SECURITY.md
  37. WATCHLISTS
README.md

Dart

An approachable, portable, and productive language for high-quality apps on any platform

Dart is:

  • Approachable: Develop with a strongly typed programming language that is consistent, concise, and offers modern language features like null safety and patterns.

  • Portable: Compile to ARM, x64, or RISC-V machine code for mobile, desktop, and backend. Compile to JavaScript or WebAssembly for the web.

  • Productive: Make changes iteratively: use hot reload to see the result instantly in your running app. Diagnose app issues using DevTools.

Dart's flexible compiler technology lets you run Dart code in different ways, depending on your target platform and goals:

  • Dart Native: For programs targeting devices (mobile, desktop, server, and more), Dart Native includes both a Dart VM with JIT (just-in-time) compilation and an AOT (ahead-of-time) compiler for producing machine code.

  • Dart Web: For programs targeting the web, Dart Web includes both a development time compiler (dartdevc) and a production time compiler (dart2js).

Dart platforms illustration

License & patents

Dart is free and open source.

See LICENSE and PATENT_GRANT.

Using Dart

Visit dart.dev to learn more about the language, tools, and to find codelabs.

Browse pub.dev for more packages and libraries contributed by the community and the Dart team.

Our API reference documentation is published at api.dart.dev, based on the stable release. (We also publish docs from our beta and dev channels, as well as from the primary development branch).

Building Dart

If you want to build Dart yourself, here is a guide to getting the source, preparing your machine to build the SDK, and building.

There are more documents in our repo at docs.

Contributing to Dart

The easiest way to contribute to Dart is to file issues.

You can also contribute patches, as described in Contributing.

Roadmap

Future plans for Dart are included in the combined Dart and Flutter roadmap on the Flutter wiki.