Android: Fatal signal 6 (SIGABRT) when getting the adapter

[Avani-A-S]

Describe the bug
For Android platform, getting this error while getting the adapter.
Fatal signal 6 (SIGABRT), code -1 (SI_QUEUE) in tid 16382 (rustapplication), pid 16382 (rustapplication)

    let manager = Manager::new().await.unwrap();

    log::info!("get the first bluetooth adapter");
    // get the first bluetooth adapter
    let adapters = manager.adapters().await?;

Taking the code reference from https://docs.rs/btleplug/0.10.4/btleplug/. This work fine on windows. When trying to cross compile for android, creating SIGABRT error.

Provided more details https://users.rust-lang.org/t/btleplug-on-android-app-issue/86339.

[qdot]

How are you building the android system? Did you build and bring in the droidplug classes from btleplug too? I'm wondering if this is a missing java symbol or something.

[Avani-A-S]

I have followed steps in this blog. I created the app with same steps and then added the btleplug too.
https://blog.devgenius.io/integrating-rust-with-android-development-ef341c2f9cca

This is my Cargo.toml file.

[qdot]

That blog has nothing to do with our project. Did you follow the extra steps outlined in our README? https://github.com/deviceplug/btleplug#android

[Avani-A-S]

First, I started implementation as per README only. Faced same error for adapter so I googled some more and found devgenius blog. Let me try again as per README and I'll share the issue with code.

[Avani-A-S]

Will you be able to list out set up steps in detail. Not sure how to build java portion of btleplug or jni-util-rs and how to connect it with my android app from the steps.

I am new with rust and android both. For local set up I need to checkout both this and add to my project?
https://github.com/deviceplug/jni-utils-rs, classcache branch
https://github.com/deviceplug/btleplug, android-tokio branch

[Avani-A-S]

Added the base code here. You might look into it provide some pointers.
https://github.com/Avani-A-S/bledemoapp

[Avani-A-S]

@qdot Followed these steps as per README and yet facing same issue. Pushed latest changes here https://github.com/Avani-A-S/bledemoapp.

Steps followed:

1. Checked out jni-utils-rs and btleplug locally.
2. Opened jni-utils-rs in Android Studio and build libs at path "jni-utils-rs\target\debug\java\libs" with following commands.

$ cargo build
$ cd java
$ ./gradlew build

3. Opened btleplug/src/droidplug/java in Android Studio. Updated build.gradle for above generated lib dependencies.

dependencies {
compile fileTree(dir: '/jni-utils-rs/target/debug/java/libs', include: ['*.jar'])
}

4. Build -> Rebuild Project. AAR generated at 'btleplug\src\droidplug\java\build\outputs\aar\droidplug-debug.aar'

5. Placed above generated .aar at my android app location 'android\app\libs'

6. Added .aar file dependencies in build.gradle.
   

7. Run the app, clicked on scan button and still facing same error when trying to get the adapter.
   

[Oppzippy]

I was getting Fatal signal 6 (SIGABRT) as well, and in my case it, turned out to be not calling btleplug::platform::init (panic was here I think: https://github.com/deviceplug/btleplug/blob/master/src/droidplug/mod.rs#L20). Building with debug symbols made it easy to find.

I don't think btleplug::platform::init is mentioned anywhere in the readme or docs, so that should probably be added.

[Avani-A-S]

Your issue resolved with btleplug::platform::init? Can you tell me where to use it.

[Oppzippy]

It's a little outdated but see the code snippet here #8 (comment). It doesn't really matter where you put it, it just needs to be called before you do anything with btleplug. So putting it in an init function that you call manually like this is fine too.

[Avani-A-S]

Yes. I tried that but facing error expected struct jni::wrapper::jnienv::JNIEnv, found struct JNIEnv.

Facing the same issue with flutter as well so reported trobanga/flutter_btleplug#4.

Not sure if this is the issue related to versions of libraries I am using -
jni-utils - 0.1.0
btleplug - 0.10.4
jni - 0.20.0

[Oppzippy]

jni should be 0.19.0

[Avani-A-S]

@Oppzippy Thanks a lot! It finally worked with jni 0.19.0 and by adding btleplug::platform::init.