Struct TerminalState 

pub struct TerminalState { /* private fields */ }

Terminal state wrapping alacritty_terminal

Implementations

impl TerminalState

pub fn new(cols: u16, rows: u16) -> Self

Create a new terminal state

pub fn drain_pty_write_queue(&self) -> Vec<String>

Drain any pending data that needs to be written back to the PTY.

This is used for responses to terminal queries like DSR (cursor position report). The caller should write this data to the PTY writer.

pub fn process_output(&mut self, data: &[u8])

Process output from the PTY

pub fn resize(&mut self, cols: u16, rows: u16)

Resize the terminal

pub fn size(&self) -> (u16, u16)

Get current dimensions

pub fn is_dirty(&self) -> bool

Check if content has changed

pub fn mark_clean(&mut self)

Mark as clean after rendering

pub fn cursor_position(&self) -> (u16, u16)

Get the cursor position (column, row)

pub fn cursor_visible(&self) -> bool

Check if cursor is visible

pub fn get_line(&self, row: u16) -> Vec<TerminalCell>

Get a line of content for rendering

Returns cells as (char, foreground_color, background_color, flags) tuples. Colors are ANSI color indices (0-255) or None for default. Accounts for scroll offset (display_offset) when accessing lines.

pub fn content_string(&self) -> String

Get all visible content as a string (for testing/debugging)

pub fn full_content_string(&self) -> String

Get all content including scrollback history as a string Lines are in chronological order (oldest first)

WARNING: This is O(total_history) and should NOT be used in hot paths. For mode switching, use the incremental streaming architecture instead:

• flush_new_scrollback() during PTY reads
• append_visible_screen() on mode exit

pub fn history_size(&self) -> usize

Get the number of scrollback history lines

pub fn title(&self) -> &str

Get the title (if set by escape sequence)

pub fn set_title(&mut self, title: String)

Set the terminal title (called when escape sequence is received)

pub fn scroll_to_bottom(&mut self)

Scroll to the bottom of the terminal (display offset = 0) Used when re-entering terminal mode from scrollback view

pub fn is_alternate_screen(&self) -> bool

Check if the terminal is in alternate screen mode. Programs like vim, less, htop use alternate screen.

pub fn wants_mouse_events(&self) -> bool

Check if the terminal wants mouse events reported. Returns true if any mouse reporting mode is enabled.

pub fn uses_sgr_mouse(&self) -> bool

Check if SGR mouse encoding is enabled (modern mouse protocol).

pub fn uses_alternate_scroll(&self) -> bool

Check if alternate scroll mode is enabled. When enabled, scroll wheel should be sent as up/down arrow keys.

pub fn is_app_cursor(&self) -> bool

Check if application cursor keys mode (DECCKM) is enabled. Programs like less, git log set this mode so that arrow keys send \x1bOA (SS3) instead of \x1b[A (CSI).

pub fn flush_new_scrollback<W: Write>( &mut self, writer: &mut W, ) -> Result<usize>

Flush any new scrollback lines to the writer.

Call this after process_output() to incrementally stream scrollback to the backing file. Returns the number of new lines written.

This is the core of the incremental streaming architecture: scrollback lines are written once as they scroll off the screen, avoiding O(n) work on mode switches.

pub fn append_visible_screen<W: Write>(&self, writer: &mut W) -> Result<()>

Append the visible screen content to the writer.

Call this when exiting terminal mode to add the current screen to the backing file. The visible screen is the “rewritable tail” that gets overwritten each time we exit terminal mode.

Only writes up to and including the last non-empty line to avoid padding the scrollback with empty lines.

pub fn backing_file_history_end(&self) -> u64

Get the byte offset where scrollback history ends in the backing file.

Used for truncating the file when re-entering terminal mode (to remove the visible screen portion).

pub fn set_backing_file_history_end(&mut self, offset: u64)

Set the byte offset where scrollback history ends.

Call this after flushing scrollback to record the file position.

pub fn synced_history_lines(&self) -> usize

Get the number of scrollback lines that have been synced to the backing file.

pub fn reset_sync_state(&mut self)

Reset sync state (e.g., when starting fresh or after truncation).