RFR: 8317611: Add a tool like jdeprscan to find usage of restricted methods

[Maurizio Cimadamore]

On Tue, 18 Jun 2024 16:30:37 GMT, Jorn Vernee <jvernee at openjdk.org> wrote:

> This PR adds a new JDK tool, called `jnativescan`, that can be used to find code that accesses native functionality. Currently this includes `native` method declarations, and methods marked with `@Restricted`.
> 
> The tool accepts a list of class path and module path entries through `--class-path` and `--module-path`, and a set of root modules through `--add-modules`, as well as an optional target release with `--release`.
> 
> The default mode is for the tool to report all uses of `@Restricted` methods, and `native` method declaration in a tree-like structure:
> 
> 
> app.jar (ALL-UNNAMED):
>   main.Main:
>     main.Main::main(String[])void references restricted methods:
>       java.lang.foreign.MemorySegment::reinterpret(long)MemorySegment
>     main.Main::m()void is a native method declaration
> 
> 
> The `--print-native-access` option can be used print out all the module names of modules doing native access in a comma separated list. For class path code, this will print out `ALL-UNNAMED`.
> 
> Testing: 
> - `langtools_jnativescan` tests.
> - Running the tool over jextract's libclang bindings, which use the FFM API, and thus has a lot of references to `@Restricted` methods.
> - tier 1-3

src/jdk.jdeps/share/classes/com/sun/tools/jnativescan/RestrictedMethodFinder.java line 43:

> 41: import java.util.*;
> 42: 
> 43: class RestrictedMethodFinder {

The name of this is a bit confusing as this class looks for both restricted methods and JNI decls

src/jdk.jdeps/share/classes/com/sun/tools/jnativescan/RestrictedMethodFinder.java line 48:

> 46:     // see make/langtools/src/classes/build/tools/symbolgenerator/CreateSymbols.java
> 47:     private static final String RESTRICTED_NAME = "Ljdk/internal/javac/Restricted+Annotation;";
> 48:     private static final List<String> RESTRICTED_MODULES = List.of("java.base");

unused?

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/19774#discussion_r1646536647
PR Review Comment: https://git.openjdk.org/jdk/pull/19774#discussion_r1646535286