Module state

State machine module.

Non-blocking state machines for all network operations. Each state machine has a step() method that returns immediately.

Design Principles

1. No blocking: step() returns immediately, never waits
2. Timeout as observation: Check elapsed time, don’t spin
3. State transitions: Move to next state when condition met
4. Composable: State machines can contain other state machines

Usage Pattern

loop {
    // Poll network stack (exactly once per iteration)
    iface.poll(now, device, sockets);
     
    // Step state machine (returns immediately)
    match state_machine.step(now_tsc, &timeouts) {
        StepResult::Pending => continue,
        StepResult::Done => break,
        StepResult::Timeout => handle_timeout(),
        StepResult::Failed => handle_error(),
    }
}

Reference

NETWORK_IMPL_GUIDE.md §5

Re-exports

• pub use dhcp::DhcpState;
• pub use dns::DnsResolveState;
• pub use download::IsoDownloadState;
• pub use http::HttpDownloadState;
• pub use tcp::TcpConnState;

Modules

• dhcp
  DHCP client state machine.
• disk_writer
  ISO Streaming Disk Writer State Machine.
• dns
  DNS resolution state machine.
• download
  ISO download orchestration state machine.
• http
  HTTP download state machine.
• tcp
  TCP connection state machine.

Structs

• Progress
  Progress information for long-running operations.
• StepContext
  Context passed to state machine step functions.
• TscTimestamp
  TSC timestamp wrapper for timeout calculations.

Enums

• StateError
  Common error type for state machines.
• StepResult
  Result of a state machine step.