WOS (WebAssembly OS) Adapter

The WosAdapter manages daemons as WebAssembly processes in WOS (WebAssembly Operating System).

Features

• Process lifecycle management via wos-ctl CLI
• 8-level priority scheduler (0-7)
• WebAssembly module isolation
• Capability-based security
• Message-passing IPC

Priority Levels

Usage

#![allow(unused)]
fn main() {
use duende_core::adapters::WosAdapter;
use duende_core::types::Signal;

// Default adapter (priority 4 - Normal)
let adapter = WosAdapter::new();

// With custom priority
let adapter = WosAdapter::with_priority(2);  // Above Normal

// Spawn daemon as WOS process
let handle = adapter.spawn(Box::new(my_daemon)).await?;
println!("WOS PID: {}", handle.wos_pid().unwrap());

// Check status
let status = adapter.status(&handle).await?;

// Send signal
adapter.signal(&handle, Signal::Term).await?;
}

How It Works

1. Spawn:
   • Allocates PID (starts at 2, PID 1 is init)
   • Runs wos-ctl spawn --name <name> --priority <level> --wasm <path>
2. Signal: Runs wos-ctl kill --pid <pid> --signal <sig>
3. Status: Runs wos-ctl status --pid <pid> --json
4. Terminate: Runs wos-ctl terminate --pid <pid>

Architecture

WOS Kernel
┌───────────────────────────────────────────┐
│  ┌─────────────┐    ┌─────────────────┐   │
│  │  Scheduler  │    │  Process Table  │   │
│  │  (8-level)  │    │                 │   │
│  └─────────────┘    └─────────────────┘   │
│         │                    │            │
│         ▼                    ▼            │
│  ┌─────────────────────────────────────┐  │
│  │         WASM Runtime                │  │
│  │  ┌───────┐ ┌───────┐ ┌───────┐     │  │
│  │  │ PID 1 │ │ PID 2 │ │ PID 3 │ ... │  │
│  │  │ init  │ │daemon1│ │daemon2│     │  │
│  │  └───────┘ └───────┘ └───────┘     │  │
│  └─────────────────────────────────────┘  │
└───────────────────────────────────────────┘

Verification

# List duende processes
wos-ctl ps | grep duende

# Check specific process
wos-ctl status --pid 42

# View process logs
wos-ctl logs --pid 42

Requirements

• WOS runtime installed
• wos-ctl CLI in PATH
• WebAssembly module compiled for WASI

Platform Detection

The adapter is selected when:

• Running inside WOS environment
• WOS_VERSION environment variable set

#![allow(unused)]
fn main() {
use duende_core::platform::detect_platform;
use duende_core::adapters::select_adapter;

let platform = detect_platform();  // Returns Platform::Wos
let adapter = select_adapter(platform);  // Returns WosAdapter
}

Configuration

[platform.wos]
priority = 4  # 0-7, default is 4 (Normal)
capabilities = ["net", "fs:read"]