Enum TerminalState 

pub enum TerminalState {
    Created,
    Running,
    ShuttingDown,
    Closed,
}

STATE MACHINE: TerminalInstance

Tracks the lifecycle of a PTY-backed terminal instance.

State Diagram:

Created ──────► Running ──────► ShuttingDown ──────► Closed │ ▲ │ (process exit, │ │ read error) │ └────────────────────────────────────┘

Transitions: Created -> Running (start signal sent via start_sender channel) Running -> ShuttingDown (shutdown_signal flag set to true) Running -> Closed (PTY process exits, reader thread detects EOF) ShuttingDown -> Closed (reader thread sees shutdown flag, exits loop)

Concurrency Invariant: Terminal I/O uses std::sync::Mutex (not tokio) because PTY operations are synchronous. The reader thread runs on a dedicated OS thread (not tokio task). ShutdownSignal uses AtomicBool for lock-free cross-thread signaling. State transitions should be synchronized through the TerminalManager’s terminals Mutex.

Interruption Table: ┌──────────────┬──────────────────────────────────────────────────────────┐ │ State │ What happens on crash/error │ ├──────────────┼──────────────────────────────────────────────────────────┤ │ Created │ PTY allocated but reader waiting for start signal. │ │ │ If app crashes: PTY master handle dropped, slave exits. │ │ │ start_sender channel dropped, reader thread unblocks │ │ │ and exits (recv() returns Err). │ ├──────────────┼──────────────────────────────────────────────────────────┤ │ Running │ Reader thread actively reading PTY output. │ │ │ If app crashes: PTY handles dropped, OS cleans up. │ │ │ If shell process exits: reader gets EOF, -> Closed. │ │ │ If reader thread panics: JoinHandle::join returns Err. │ │ │ Writer can still try to write (will get error). │ ├──────────────┼──────────────────────────────────────────────────────────┤ │ ShuttingDown │ Shutdown flag set. Reader thread checking flag each │ │ │ iteration. May take up to one read timeout to notice. │ │ │ If reader hangs on blocking read: may not shut down │ │ │ gracefully. Consider: close PTY master to force EOF. │ ├──────────────┼──────────────────────────────────────────────────────────┤ │ Closed │ Reader thread joined. PTY resources released. │ │ │ Terminal entry removed from TerminalManager map. │ └──────────────┴──────────────────────────────────────────────────────────┘

Variants

Created

Running

ShuttingDown

Closed

Trait Implementations

impl Clone for TerminalState

fn clone(&self) -> TerminalState

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for TerminalState

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for TerminalState

fn eq(&self, other: &TerminalState) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for TerminalState

impl Eq for TerminalState

impl StructuralPartialEq for TerminalState