[mono] Audit embedding API for .NET 5 correctness

[lambdageek]

This is a tracking issue to audit the public embedding API for correctness with respect to assembly load context support.

The goal is to consider how each function in the headers below will behave when there are multiple ALCs in the managed code, and to decide whether the function behavior needs to be corrected, or if it is not feasible to correct, whether the function's documentation should be updated with a deprecation note and a new ALC-aware replacement added.

The top priority are functions that are mentioned in xamarin-macios exports.t4 or headers that are used in the source code in the xamarin android monodroid/jni directory, and Java.Interop

• mono/utils
  • mono-logger.h
  • mono-error.h
  • mono-forward.h
  • mono-publib.h
  • mono-jemalloc.h
  • mono-dl-fallback.h
  • mono-counters.h
• mono/metadata
  • appdomain.h
  • assembly.h
  • attrdefs.h
  • blob.h
  • class.h
  • debug-helpers.h
  • debug-mono-symfile.h
  • environment.h
  • exception.h
  • image.h
  • loader.h
  • metadata.h
  • mono-config.h
  • mono-debug.h
  • mono-gc.h
  • object.h
  • object-forward.h
  • opcodes.h
  • profiler.h
  • profiler-events.h
  • reflection.h
  • row-indexes.h
  • sgen-bridge.h
  • threads.h
  • tokentype.h
  • verify.h
• mono/mini
  • jit.h

The following headers aren't installed, but they have MONO_API functions, and should be audited too:

Mini

• mono/utils/mini-runtime.h
• mono/utils/monovm.h
• mono/utils/mini.h
• mono/utils/mini-llvm.h
• mono/utils/aot-runtime.h
• mono/utils/debugger-agent.h

Metadata:

• mono/metadata/cil-coff.h
• mono/metadata/marshal-ilgen.h
• mono/metadata/marshal.h
• mono/metadata/coree.h
• mono/metadata/assembly-internals.h
• mono/metadata/sgen-toggleref.h
• mono/metadata/class-internals.h
• mono/metadata/w32file.h
• mono/metadata/security-core-clr.h
• mono/metadata/metadata-internals.h
• mono/metadata/monitor.h
• mono/metadata/object-internals.h
• mono/metadata/mono-mlist.h
• mono/metadata/method-builder-ilgen.h
• mono/metadata/filewatcher.h
• mono/metadata/threads-types.h
• mono/metadata/cominterop.h
• mono/metadata/mempool.h
• mono/metadata/mono-perfcounters.h
• mono/metadata/icall-table.h
• mono/metadata/mono-hash.h
• mono/metadata/gc-internals.h

Utils

• mono/utils/mono-path.h
• mono/utils/mono-linked-list-set.h
• mono/utils/mono-proclib.h
• mono/utils/mono-logger-internals.h
• mono/utils/strenc.h
• mono/utils/hazard-pointer.h
• mono/utils/mono-threads-api.h
• mono/utils/mono-dl-fallback.h
• mono/utils/mono-embed.h
• mono/utils/mono-error-internals.h
• mono/utils/mono-digest.h
• mono/utils/os-event.h
• mono/utils/mono-threads.h
• mono/utils/monobitset.h
• mono/utils/mono-uri.h
• mono/utils/mono-mmap.h
• mono/utils/lock-free-alloc.h
• mono/utils/mono-conc-hashtable.h
• mono/utils/lock-free-queue.h
• mono/utils/mono-logger.h
• mono/utils/mono-poll.h

[Dotnet-GitSync-Bot]

I couldn't add an area label to this Issue.

Checkout this page to find out which area owner to ping, or please add exactly one area label to help train me in the future.

[lambdageek]

/cc @CoffeeFlux @steveisok @mdh1418

[CoffeeFlux]

It's worth noting this isn't just for ALCs, it's for netcore changes in general. ALC support is just going to be the most frequent incompatibility.

[CoffeeFlux]

We should also consider as part of this what ALC functions to put in public headers. Things like getting the default ALC for a domain will be useful to embedders.

[mdh1418]

In xamarin android monodroid/jni direcotry, I found the following header files referenced by the corresponding files in the directory. Everything else lacked a reference.

utils/mono-publib.h         | monodroid.h monodroid-glue.hh
utils/mono-dl-fallback.h    | monodroid-glue.cc
utils/mono-counters.h       | monodroid-glue-internal.hh
metadata/appdomain.h        | designer-assemblies.cc designer-assemblies.hh monodroid-glue.cc monodroid-glue.hh timezones.cc util.cc util.hh
metadata/assembly.h         | designer-assemblies.cc designer-assemblies.hh embedded-assemblies.cc embedded-assemblies.hh embedded-assemblies-zip.cc monodroid-glue.cc timezones.cc util.cc util.hh
metadata/class.h            | osbridge.cc timezones.cc
metadata/debug-helpers.h    | monodroid-glue.cc
metadata/image.h            | embedded-assemblies.cc xamarin-app.hh
metadata/mono-config.h      | embedded-assemblies.cc monodroid-glue.cc
metadata/mono-debug.h       | debug.cc monodroid-glue.cc
metadata/object.h           | embedded-assemblies.hh osbridge.cc timezones.cc
metadata/profiler.h         | monodroid-glue-internal.hh
metadata/reflection.h       | designer-assemblies.cc
metadata/sgen-bridge.h      | osbridge.hh
metadata/threads.h          | osbridge.cc timezones.cc

utils/mono-dl-fallback.h    | monodroid-glue.cc

In the jni directory, I ran the following command in powershell after creating an array filled with the header files
foreach ($element in $headers_array) {if (Get-ChildItem -Recurse | Select-String $element -List ) {"$element | $(Get-ChildItem -Recurse | Select-String $element -List -SimpleMatch | Select Path | Split-Path -leaf)"}}

[mdh1418]

Similarly in Java.Interop the following headers are referenced by the corresponding files in the Java.Interop directory.

utils/mono-dl-fallback.h    | java-interop-mono.h
utils/mono-counters.h       | java-interop-mono.h
metadata/assembly.h         | java-interop-mono.h
metadata/class.h            | java-interop-mono.h
metadata/object.h           | java-interop-mono.h
metadata/sgen-bridge.h      | java-interop-mono.h
metadata/threads.h          | java-interop-mono.h

utils/mono-dl-fallback.h    | java-interop-mono.h

[mdh1418]

In xamarin-macios exports.t4 the following headers are referenced.

utils/mono-publib.h         | exports.t4
metadata/appdomain.h        | exports.t4
metadata/assembly.h         | exports.t4
metadata/class.h            | exports.t4
metadata/debug-helpers.h    | exports.t4
metadata/exception.h        | exports.t4
metadata/loader.h           | exports.t4
metadata/metadata.h         | exports.t4
metadata/mono-config.h      | exports.t4
metadata/mono-debug.h       | exports.t4
metadata/mono-gc.h          | exports.t4
metadata/object.h           | exports.t4
metadata/profiler.h         | exports.t4
metadata/reflection.h       | exports.t4
metadata/threads.h          | exports.t4
mini/jit.h                  | exports.t4

metadata/marshal.h          | exports.t4
metadata/sgen-toggleref.h   | exports.t4
metadata/class-internals.h  | exports.t4
metadata/object-internals.h | exports.t4
metadata/threads-types.h    | exports.t4
metadata/mono-hash.h        | exports.t4
utils/mono-path.h           | exports.t4
utils/mono-threads-api.h    | exports.t4
utils/mono-threads.h        | exports.t4