quicproquo/sdks/kotlin

QuicProQuo Kotlin SDK

Kotlin/JVM wrapper over libquicproquo_ffi via JNI for Android and JVM platforms.

Prerequisites

• Kotlin 1.9+ / JDK 17+
• libquicproquo_ffi built for the target architecture
• JNI bridge compiled (jni/dev_quicproquo_NativeBridge.c)

Building the Native Library

# Linux (JVM)
cargo build --release -p quicproquo-ffi

# Android (aarch64)
cargo build --release -p quicproquo-ffi --target aarch64-linux-android

# Android (armv7)
cargo build --release -p quicproquo-ffi --target armv7-linux-androideabi

Compiling the JNI Bridge

cd jni
gcc -shared -fPIC -o libquicproquo_jni.so \
    -I"$JAVA_HOME/include" -I"$JAVA_HOME/include/linux" \
    dev_quicproquo_NativeBridge.c \
    -L ../../../../target/release -lquicproquo_ffi

Installation

Gradle

dependencies {
    implementation(files("libs/quicproquo-0.1.0.jar"))
}

Or include as a local project module.

Usage

import dev.quicproquo.QpqClient

val client = QpqClient("127.0.0.1:5001", caCertPath = "ca.pem")

client.login("alice", "secret")
client.send("bob", "hello".toByteArray())

val messages = client.receive(timeoutMs = 5000)
messages.forEach { println("Received: $it") }

client.close()

API

Method	Description
QpqClient(server, caCertPath, serverName)	Connect to server
client.login(username, password)	OPAQUE authentication
client.send(recipient, message)	Send message by username
client.receive(timeoutMs)	Receive pending messages
client.close() / client.disconnect()	Disconnect
client.isConnected	Connection status

Error Handling

try {
    client.login("alice", "wrong")
} catch (e: QpqAuthException) {
    println("Auth failed: ${e.message}")
} catch (e: QpqTimeoutException) {
    println("Timeout: ${e.message}")
} catch (e: QpqException) {
    println("Error: ${e.message}")
}

Structure

• src/main/kotlin/dev/quicproquo/QpqClient.kt -- High-level client
• src/main/kotlin/dev/quicproquo/NativeBridge.kt -- JNI declarations
• src/main/kotlin/dev/quicproquo/QpqError.kt -- Exception types
• jni/dev_quicproquo_NativeBridge.c -- JNI C bridge to FFI

Android Integration

1. Add the native libraries to src/main/jniLibs/<abi>/:
   • arm64-v8a/libquicproquo_ffi.so
   • armeabi-v7a/libquicproquo_ffi.so
2. Add the JNI bridge library alongside
3. The NativeBridge class loads the library via System.loadLibrary

Cross-Compilation

# Install Android NDK targets
rustup target add aarch64-linux-android armv7-linux-androideabi

# Build with the NDK linker
CARGO_TARGET_AARCH64_LINUX_ANDROID_LINKER=aarch64-linux-android21-clang \
  cargo build --release -p quicproquo-ffi --target aarch64-linux-android