1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284
//! Provides a low-level terminal interface
use std::io;
use std::time::Duration;
use mortal::{self, PrepareConfig, PrepareState, TerminalReadGuard, TerminalWriteGuard};
use sys;
pub use mortal::{CursorMode, Signal, SignalSet, Size};
/// Default `Terminal` interface
pub struct DefaultTerminal(mortal::Terminal);
/// Represents the result of a `Terminal` read operation
pub enum RawRead {
/// `n` bytes were read from the device
Bytes(usize),
/// The terminal window was resized
Resize(Size),
/// A signal was received while waiting for input
Signal(Signal),
}
/// Defines a low-level interface to the terminal
pub trait Terminal: Sized + Send + Sync {
// TODO: When generic associated types are implemented (and stabilized),
// boxed trait objects may be replaced by `Reader` and `Writer`.
/// Returned by `prepare`; passed to `restore` to restore state.
type PrepareState;
/*
/// Holds an exclusive read lock and provides read operations
type Reader: TerminalReader;
/// Holds an exclusive write lock and provides write operations
type Writer: TerminalWriter;
*/
/// Returns the name of the terminal.
fn name(&self) -> &str;
/// Acquires a lock on terminal read operations and returns a value holding
/// that lock and granting access to such operations.
///
/// The lock must not be released until the returned value is dropped.
fn lock_read<'a>(&'a self) -> Box<TerminalReader<Self> + 'a>;
/// Acquires a lock on terminal write operations and returns a value holding
/// that lock and granting access to such operations.
///
/// The lock must not be released until the returned value is dropped.
fn lock_write<'a>(&'a self) -> Box<TerminalWriter<Self> + 'a>;
}
/// Holds a lock on `Terminal` read operations
pub trait TerminalReader<Term: Terminal> {
/// Prepares the terminal for line reading and editing operations.
///
/// If `block_signals` is `true`, the terminal will be configured to treat
/// special characters that would otherwise be interpreted as signals as
/// their literal value.
///
/// If `block_signals` is `false`, a signal contained in the `report_signals`
/// set may be returned.
///
/// # Notes
///
/// This method may be called more than once. However, if the state values
/// are not restored in reverse order in which they were created,
/// the state of the underlying terminal device becomes undefined.
fn prepare(&mut self, block_signals: bool, report_signals: SignalSet)
-> io::Result<Term::PrepareState>;
/// Like `prepare`, but called when the write lock is already held.
///
/// # Safety
///
/// This method must be called with a `TerminalWriter` instance returned
/// by the same `Terminal` instance to which this `TerminalReader` belongs.
unsafe fn prepare_with_lock(&mut self, lock: &mut TerminalWriter<Term>,
block_signals: bool, report_signals: SignalSet)
-> io::Result<Term::PrepareState>;
/// Restores the terminal state using the given state data.
fn restore(&mut self, state: Term::PrepareState) -> io::Result<()>;
/// Like `restore`, but called when the write lock is already held.
///
/// # Safety
///
/// This method must be called with a `TerminalWriter` instance returned
/// by the same `Terminal` instance to which this `TerminalReader` belongs.
unsafe fn restore_with_lock(&mut self, lock: &mut TerminalWriter<Term>,
state: Term::PrepareState) -> io::Result<()>;
/// Reads some input from the terminal and appends it to the given buffer.
fn read(&mut self, buf: &mut Vec<u8>) -> io::Result<RawRead>;
/// Waits `timeout` for user input. If `timeout` is `None`, waits indefinitely.
///
/// Returns `Ok(true)` if input becomes available within the given timeout
/// or if a signal is received.
///
/// Returns `Ok(false)` if the timeout expires before input becomes available.
fn wait_for_input(&mut self, timeout: Option<Duration>) -> io::Result<bool>;
}
/// Holds a lock on `Terminal` write operations
pub trait TerminalWriter<Term: Terminal> {
/// Returns the size of the terminal window
fn size(&self) -> io::Result<Size>;
/// Presents a clear terminal screen, with cursor at first row, first column.
///
/// If the terminal possesses a scrolling window over a buffer, this shall
/// have the effect of moving the visible window down such that it shows
/// an empty view of the buffer, preserving some or all of existing buffer
/// contents, where possible.
fn clear_screen(&mut self) -> io::Result<()>;
/// Clears characters on the line occupied by the cursor, beginning with the
/// cursor and ending at the end of the line. Also clears all characters on
/// all lines after the cursor.
fn clear_to_screen_end(&mut self) -> io::Result<()>;
/// Moves the cursor up `n` cells; `n` may be zero.
fn move_up(&mut self, n: usize) -> io::Result<()>;
/// Moves the cursor down `n` cells; `n` may be zero.
fn move_down(&mut self, n: usize) -> io::Result<()>;
/// Moves the cursor left `n` cells; `n` may be zero.
fn move_left(&mut self, n: usize) -> io::Result<()>;
/// Moves the cursor right `n` cells; `n` may be zero.
fn move_right(&mut self, n: usize) -> io::Result<()>;
/// Moves the cursor to the first column of the current line
fn move_to_first_column(&mut self) -> io::Result<()>;
/// Set the current cursor mode
fn set_cursor_mode(&mut self, mode: CursorMode) -> io::Result<()>;
/// Writes output to the terminal.
///
/// For each carriage return `'\r'` written to the terminal, the cursor
/// should be moved to the first column of the current line.
///
/// For each newline `'\n'` written to the terminal, the cursor should
/// be moved to the first column of the following line.
///
/// The terminal interface shall not automatically move the cursor to the next
/// line when `write` causes a character to be written to the final column.
fn write(&mut self, s: &str) -> io::Result<()>;
/// Flushes any currently buffered output data.
///
/// `TerminalWriter` instances may not buffer data on all systems.
///
/// Data must be flushed when the `TerminalWriter` instance is dropped.
fn flush(&mut self) -> io::Result<()>;
}
impl DefaultTerminal {
/// Opens access to the terminal device associated with standard output.
pub fn new() -> io::Result<DefaultTerminal> {
mortal::Terminal::new().map(DefaultTerminal)
}
/// Opens access to the terminal device associated with standard error.
pub fn stderr() -> io::Result<DefaultTerminal> {
mortal::Terminal::stderr().map(DefaultTerminal)
}
unsafe fn cast_writer<'a>(writer: &'a mut TerminalWriter<Self>)
-> &'a mut TerminalWriteGuard<'a> {
&mut *(writer as *mut _ as *mut TerminalWriteGuard)
}
}
impl Terminal for DefaultTerminal {
type PrepareState = PrepareState;
fn name(&self) -> &str {
self.0.name()
}
fn lock_read<'a>(&'a self) -> Box<TerminalReader<Self> + 'a> {
Box::new(self.0.lock_read().unwrap())
}
fn lock_write<'a>(&'a self) -> Box<TerminalWriter<Self> + 'a> {
Box::new(self.0.lock_write().unwrap())
}
}
impl<'a> TerminalReader<DefaultTerminal> for TerminalReadGuard<'a> {
fn prepare(&mut self, block_signals: bool, report_signals: SignalSet)
-> io::Result<PrepareState> {
self.prepare(PrepareConfig{
block_signals,
enable_control_flow: !block_signals,
enable_keypad: false,
report_signals,
.. PrepareConfig::default()
})
}
unsafe fn prepare_with_lock(&mut self,
lock: &mut TerminalWriter<DefaultTerminal>,
block_signals: bool, report_signals: SignalSet)
-> io::Result<PrepareState> {
let lock = DefaultTerminal::cast_writer(lock);
self.prepare_with_lock(lock, PrepareConfig{
block_signals,
enable_control_flow: !block_signals,
enable_keypad: false,
report_signals,
.. PrepareConfig::default()
})
}
fn restore(&mut self, state: PrepareState) -> io::Result<()> {
self.restore(state)
}
unsafe fn restore_with_lock(&mut self,
lock: &mut TerminalWriter<DefaultTerminal>, state: PrepareState)
-> io::Result<()> {
let lock = DefaultTerminal::cast_writer(lock);
self.restore_with_lock(lock, state)
}
fn read(&mut self, buf: &mut Vec<u8>) -> io::Result<RawRead> {
sys::terminal_read(self, buf)
}
fn wait_for_input(&mut self, timeout: Option<Duration>) -> io::Result<bool> {
self.wait_event(timeout)
}
}
impl<'a> TerminalWriter<DefaultTerminal> for TerminalWriteGuard<'a> {
fn size(&self) -> io::Result<Size> {
self.size()
}
fn clear_screen(&mut self) -> io::Result<()> {
self.clear_screen()
}
fn clear_to_screen_end(&mut self) -> io::Result<()> {
self.clear_to_screen_end()
}
fn move_up(&mut self, n: usize) -> io::Result<()> {
self.move_up(n)
}
fn move_down(&mut self, n: usize) -> io::Result<()> {
self.move_down(n)
}
fn move_left(&mut self, n: usize) -> io::Result<()> {
self.move_left(n)
}
fn move_right(&mut self, n: usize) -> io::Result<()> {
self.move_right(n)
}
fn move_to_first_column(&mut self) -> io::Result<()> {
self.move_to_first_column()
}
fn set_cursor_mode(&mut self, mode: CursorMode) -> io::Result<()> {
self.set_cursor_mode(mode)
}
fn write(&mut self, s: &str) -> io::Result<()> {
self.write_str(s)
}
fn flush(&mut self) -> io::Result<()> {
self.flush()
}
}