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|
mod table;
mod definitions;
pub use definitions::{Action, State, unpack};
use table::{EXIT_ACTIONS, ENTRY_ACTIONS, STATE_CHANGE};
impl State {
/// Get exit action for this state
#[inline(always)]
pub fn exit_action(&self) -> Action {
unsafe {
*EXIT_ACTIONS.get_unchecked(*self as usize)
}
}
/// Get entry action for this state
#[inline(always)]
pub fn entry_action(&self) -> Action {
unsafe {
*ENTRY_ACTIONS.get_unchecked(*self as usize)
}
}
}
pub struct StateMachine<P: Parser> {
state: State,
parser: P,
}
impl<P: Parser> StateMachine<P> {
pub fn advance(&mut self, byte: u8) {
// Handle state changes in the anywhere state before evaluating changes
// for current state.
let mut change = STATE_CHANGE[State::Anywhere as usize][byte as usize];
if change == 0 {
change = STATE_CHANGE[self.state as usize][byte as usize];
}
// Unpack into a state and action
let (state, action) = unpack(change);
self.perform_state_change(state, action, byte);
}
fn perform_state_change(&mut self, state: State, action: Action, byte: u8) {
macro_rules! maybe_action {
($action:expr, $arg:expr) => {
match $action {
Action::None | Action::Unused__ => (),
action => {
self.perform_action(action, $arg);
},
}
}
}
match state {
State::Anywhere | State::Unused__ => {
// Just run the action
self.perform_action(action, byte);
},
state => {
// Exit action for previous state
let exit_action = self.state.exit_action();
maybe_action!(exit_action, 0);
// Transition action
maybe_action!(action, byte);
// Entry action for new state
maybe_action!(state.entry_action(), 0);
// Assume the new state
self.state = state;
}
}
}
/// XXX I don't think this handles UTF-8 properly. Hmm...
fn perform_action(&mut self, action: Action, byte: u8) {
unimplemented!();
match action {
Action::Execute => self.parser.execute(byte),
Action::Hook => self.parser.hook(byte),
Action::Put => self.parser.put(byte),
Action::OscStart => self.parser.osc_start(byte),
Action::OscPut => self.parser.osc_put(byte),
Action::OscEnd => self.parser.osc_end(byte),
Action::Unhook => self.parser.unhook(byte),
Action::CsiDispatch => self.parser.csi_dispatch(byte),
Action::EscDispatch => self.parser.esc_dispatch(byte),
Action::Ignore | Action::None | Action::Unused__=> (),
Action::Collect => {
unimplemented!();
},
Action::Param => {
unimplemented!();
},
Action::Clear => {
unimplemented!();
}
}
}
}
pub trait Parser {
fn csi_entry(&mut self, byte: u8);
fn csi_param(&mut self, byte: u8);
}
//
// struct Foo;
//
// impl Parser for Foo {
// fn csi_entry(&mut self, c: char) {
// println!("csi_entry char={:?}", c);
// }
// fn csi_param(&mut self, c: char) {
// println!("csi_param char={:?}", c);
// }
// }
//
// #[test]
// fn it_works() {
// let table: u8 = &[Parser::csi_entry, Parser::csi_param];
// let mut foo = Foo;
// table[0](&mut foo, 'b');
// }
|
