Embedder loading broken since Linux support was added

[jwinarske]

Description

When running rive package via custom embedder (e.g. Toyota embedder), it fails to load librive_text.so even though it is in the system search path.

The expectation is that librive_text.so is linked to the process. This is true for the Linux GTK embedder, as it links into an executable linking the shared modules. This is not true for custom embedders.

rive-common for Linux case defaults to using

return DynamicLibrary.process();

This only works if librive_text.so is linked to executable at compile time. Otherwise you get this error:

Sep 06 17:27:52 qemux86-64 flutter-auto[473]: [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: Invalid argument(s): Failed to lookup symbol 'init': /usr/share/flutter/flutter_ics_homescreen/3.24.1/release/lib/libflutter_engine.so: undefined symbo>
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: #0      DynamicLibrary.lookup (dart:ffi-patch/ffi_dynamic_library_patch.dart:33)
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: #1      init (package:rive_common/src/rive_text_ffi.dart:493)
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: #2      initFont (package:rive_common/src/rive_text_ffi.dart)
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: #3      Font.initialize (package:rive_common/rive_text.dart:461)
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: #4      RiveFile.initialize (package:rive/src/rive_file.dart:392)
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: #5      RiveFile._initTextAndImport (package:rive/src/rive_file.dart:414)
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: #6      RiveFile.asset (package:rive/src/rive_file.dart:444)
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: <asynchronous suspension>
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: #7      RiveAnimationState._configure (package:rive/src/widgets/rive_animation.dart:212)
Sep 06 17:27:52 qemux86-64 flutter-auto[473]: <asynchronous suspension>

Expected behavior

if the shared module is present in the LD_LIBRARY_PATH it should load; independent of linking behavior.

Device & Versions (please complete the following information)

• Device: Embedded Linux
• OS: Any Linux distro
• Flutter Version: 3.24.1

[jwinarske]

Two validated workarounds:

1. Link librive-text.so at build time to embedder
2. Dynamically load librive-text.so at runtime prior to flutter app running