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Diffstat (limited to 'library/term/src/terminfo/parm.rs')
| -rw-r--r-- | library/term/src/terminfo/parm.rs | 559 |
1 files changed, 559 insertions, 0 deletions
diff --git a/library/term/src/terminfo/parm.rs b/library/term/src/terminfo/parm.rs new file mode 100644 index 00000000000..2e4e917891e --- /dev/null +++ b/library/term/src/terminfo/parm.rs @@ -0,0 +1,559 @@ +//! Parameterized string expansion + +use self::Param::*; +use self::States::*; + +use std::iter::repeat; + +#[cfg(test)] +mod tests; + +#[derive(Clone, Copy, PartialEq)] +enum States { + Nothing, + Percent, + SetVar, + GetVar, + PushParam, + CharConstant, + CharClose, + IntConstant(i32), + FormatPattern(Flags, FormatState), + SeekIfElse(usize), + SeekIfElsePercent(usize), + SeekIfEnd(usize), + SeekIfEndPercent(usize), +} + +#[derive(Copy, PartialEq, Clone)] +enum FormatState { + Flags, + Width, + Precision, +} + +/// Types of parameters a capability can use +#[allow(missing_docs)] +#[derive(Clone)] +pub enum Param { + Words(String), + Number(i32), +} + +/// Container for static and dynamic variable arrays +pub struct Variables { + /// Static variables A-Z + sta_va: [Param; 26], + /// Dynamic variables a-z + dyn_va: [Param; 26], +} + +impl Variables { + /// Returns a new zero-initialized Variables + pub fn new() -> Variables { + Variables { + sta_va: [ + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + ], + dyn_va: [ + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + ], + } + } +} + +/// Expand a parameterized capability +/// +/// # Arguments +/// * `cap` - string to expand +/// * `params` - vector of params for %p1 etc +/// * `vars` - Variables struct for %Pa etc +/// +/// To be compatible with ncurses, `vars` should be the same between calls to `expand` for +/// multiple capabilities for the same terminal. +pub fn expand(cap: &[u8], params: &[Param], vars: &mut Variables) -> Result<Vec<u8>, String> { + let mut state = Nothing; + + // expanded cap will only rarely be larger than the cap itself + let mut output = Vec::with_capacity(cap.len()); + + let mut stack: Vec<Param> = Vec::new(); + + // Copy parameters into a local vector for mutability + let mut mparams = [ + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + Number(0), + ]; + for (dst, src) in mparams.iter_mut().zip(params.iter()) { + *dst = (*src).clone(); + } + + for &c in cap.iter() { + let cur = c as char; + let mut old_state = state; + match state { + Nothing => { + if cur == '%' { + state = Percent; + } else { + output.push(c); + } + } + Percent => { + match cur { + '%' => { + output.push(c); + state = Nothing + } + 'c' => { + match stack.pop() { + // if c is 0, use 0200 (128) for ncurses compatibility + Some(Number(0)) => output.push(128u8), + // Don't check bounds. ncurses just casts and truncates. + Some(Number(c)) => output.push(c as u8), + Some(_) => return Err("a non-char was used with %c".to_string()), + None => return Err("stack is empty".to_string()), + } + } + 'p' => state = PushParam, + 'P' => state = SetVar, + 'g' => state = GetVar, + '\'' => state = CharConstant, + '{' => state = IntConstant(0), + 'l' => match stack.pop() { + Some(Words(s)) => stack.push(Number(s.len() as i32)), + Some(_) => return Err("a non-str was used with %l".to_string()), + None => return Err("stack is empty".to_string()), + }, + '+' | '-' | '/' | '*' | '^' | '&' | '|' | 'm' => { + match (stack.pop(), stack.pop()) { + (Some(Number(y)), Some(Number(x))) => stack.push(Number(match cur { + '+' => x + y, + '-' => x - y, + '*' => x * y, + '/' => x / y, + '|' => x | y, + '&' => x & y, + '^' => x ^ y, + 'm' => x % y, + _ => unreachable!("All cases handled"), + })), + (Some(_), Some(_)) => { + return Err(format!("non-numbers on stack with {}", cur)); + } + _ => return Err("stack is empty".to_string()), + } + } + '=' | '>' | '<' | 'A' | 'O' => match (stack.pop(), stack.pop()) { + (Some(Number(y)), Some(Number(x))) => stack.push(Number( + if match cur { + '=' => x == y, + '<' => x < y, + '>' => x > y, + 'A' => x > 0 && y > 0, + 'O' => x > 0 || y > 0, + _ => unreachable!(), + } { + 1 + } else { + 0 + }, + )), + (Some(_), Some(_)) => { + return Err(format!("non-numbers on stack with {}", cur)); + } + _ => return Err("stack is empty".to_string()), + }, + '!' | '~' => match stack.pop() { + Some(Number(x)) => stack.push(Number(match cur { + '!' if x > 0 => 0, + '!' => 1, + '~' => !x, + _ => unreachable!(), + })), + Some(_) => return Err(format!("non-numbers on stack with {}", cur)), + None => return Err("stack is empty".to_string()), + }, + 'i' => match (&mparams[0], &mparams[1]) { + (&Number(x), &Number(y)) => { + mparams[0] = Number(x + 1); + mparams[1] = Number(y + 1); + } + _ => return Err("first two params not numbers with %i".to_string()), + }, + + // printf-style support for %doxXs + 'd' | 'o' | 'x' | 'X' | 's' => { + if let Some(arg) = stack.pop() { + let flags = Flags::new(); + let res = format(arg, FormatOp::from_char(cur), flags)?; + output.extend(res.iter().cloned()); + } else { + return Err("stack is empty".to_string()); + } + } + ':' | '#' | ' ' | '.' | '0'..='9' => { + let mut flags = Flags::new(); + let mut fstate = FormatState::Flags; + match cur { + ':' => (), + '#' => flags.alternate = true, + ' ' => flags.space = true, + '.' => fstate = FormatState::Precision, + '0'..='9' => { + flags.width = cur as usize - '0' as usize; + fstate = FormatState::Width; + } + _ => unreachable!(), + } + state = FormatPattern(flags, fstate); + } + + // conditionals + '?' => (), + 't' => match stack.pop() { + Some(Number(0)) => state = SeekIfElse(0), + Some(Number(_)) => (), + Some(_) => return Err("non-number on stack with conditional".to_string()), + None => return Err("stack is empty".to_string()), + }, + 'e' => state = SeekIfEnd(0), + ';' => (), + _ => return Err(format!("unrecognized format option {}", cur)), + } + } + PushParam => { + // params are 1-indexed + stack.push( + mparams[match cur.to_digit(10) { + Some(d) => d as usize - 1, + None => return Err("bad param number".to_string()), + }] + .clone(), + ); + } + SetVar => { + if cur >= 'A' && cur <= 'Z' { + if let Some(arg) = stack.pop() { + let idx = (cur as u8) - b'A'; + vars.sta_va[idx as usize] = arg; + } else { + return Err("stack is empty".to_string()); + } + } else if cur >= 'a' && cur <= 'z' { + if let Some(arg) = stack.pop() { + let idx = (cur as u8) - b'a'; + vars.dyn_va[idx as usize] = arg; + } else { + return Err("stack is empty".to_string()); + } + } else { + return Err("bad variable name in %P".to_string()); + } + } + GetVar => { + if cur >= 'A' && cur <= 'Z' { + let idx = (cur as u8) - b'A'; + stack.push(vars.sta_va[idx as usize].clone()); + } else if cur >= 'a' && cur <= 'z' { + let idx = (cur as u8) - b'a'; + stack.push(vars.dyn_va[idx as usize].clone()); + } else { + return Err("bad variable name in %g".to_string()); + } + } + CharConstant => { + stack.push(Number(c as i32)); + state = CharClose; + } + CharClose => { + if cur != '\'' { + return Err("malformed character constant".to_string()); + } + } + IntConstant(i) => { + if cur == '}' { + stack.push(Number(i)); + state = Nothing; + } else if let Some(digit) = cur.to_digit(10) { + match i.checked_mul(10).and_then(|i_ten| i_ten.checked_add(digit as i32)) { + Some(i) => { + state = IntConstant(i); + old_state = Nothing; + } + None => return Err("int constant too large".to_string()), + } + } else { + return Err("bad int constant".to_string()); + } + } + FormatPattern(ref mut flags, ref mut fstate) => { + old_state = Nothing; + match (*fstate, cur) { + (_, 'd') | (_, 'o') | (_, 'x') | (_, 'X') | (_, 's') => { + if let Some(arg) = stack.pop() { + let res = format(arg, FormatOp::from_char(cur), *flags)?; + output.extend(res.iter().cloned()); + // will cause state to go to Nothing + old_state = FormatPattern(*flags, *fstate); + } else { + return Err("stack is empty".to_string()); + } + } + (FormatState::Flags, '#') => { + flags.alternate = true; + } + (FormatState::Flags, '-') => { + flags.left = true; + } + (FormatState::Flags, '+') => { + flags.sign = true; + } + (FormatState::Flags, ' ') => { + flags.space = true; + } + (FormatState::Flags, '0'..='9') => { + flags.width = cur as usize - '0' as usize; + *fstate = FormatState::Width; + } + (FormatState::Flags, '.') => { + *fstate = FormatState::Precision; + } + (FormatState::Width, '0'..='9') => { + let old = flags.width; + flags.width = flags.width * 10 + (cur as usize - '0' as usize); + if flags.width < old { + return Err("format width overflow".to_string()); + } + } + (FormatState::Width, '.') => { + *fstate = FormatState::Precision; + } + (FormatState::Precision, '0'..='9') => { + let old = flags.precision; + flags.precision = flags.precision * 10 + (cur as usize - '0' as usize); + if flags.precision < old { + return Err("format precision overflow".to_string()); + } + } + _ => return Err("invalid format specifier".to_string()), + } + } + SeekIfElse(level) => { + if cur == '%' { + state = SeekIfElsePercent(level); + } + old_state = Nothing; + } + SeekIfElsePercent(level) => { + if cur == ';' { + if level == 0 { + state = Nothing; + } else { + state = SeekIfElse(level - 1); + } + } else if cur == 'e' && level == 0 { + state = Nothing; + } else if cur == '?' { + state = SeekIfElse(level + 1); + } else { + state = SeekIfElse(level); + } + } + SeekIfEnd(level) => { + if cur == '%' { + state = SeekIfEndPercent(level); + } + old_state = Nothing; + } + SeekIfEndPercent(level) => { + if cur == ';' { + if level == 0 { + state = Nothing; + } else { + state = SeekIfEnd(level - 1); + } + } else if cur == '?' { + state = SeekIfEnd(level + 1); + } else { + state = SeekIfEnd(level); + } + } + } + if state == old_state { + state = Nothing; + } + } + Ok(output) +} + +#[derive(Copy, PartialEq, Clone)] +struct Flags { + width: usize, + precision: usize, + alternate: bool, + left: bool, + sign: bool, + space: bool, +} + +impl Flags { + fn new() -> Flags { + Flags { width: 0, precision: 0, alternate: false, left: false, sign: false, space: false } + } +} + +#[derive(Copy, Clone)] +enum FormatOp { + Digit, + Octal, + LowerHex, + UpperHex, + String, +} + +impl FormatOp { + fn from_char(c: char) -> FormatOp { + match c { + 'd' => FormatOp::Digit, + 'o' => FormatOp::Octal, + 'x' => FormatOp::LowerHex, + 'X' => FormatOp::UpperHex, + 's' => FormatOp::String, + _ => panic!("bad FormatOp char"), + } + } + fn to_char(self) -> char { + match self { + FormatOp::Digit => 'd', + FormatOp::Octal => 'o', + FormatOp::LowerHex => 'x', + FormatOp::UpperHex => 'X', + FormatOp::String => 's', + } + } +} + +fn format(val: Param, op: FormatOp, flags: Flags) -> Result<Vec<u8>, String> { + let mut s = match val { + Number(d) => { + match op { + FormatOp::Digit => { + if flags.sign { + format!("{:+01$}", d, flags.precision) + } else if d < 0 { + // C doesn't take sign into account in precision calculation. + format!("{:01$}", d, flags.precision + 1) + } else if flags.space { + format!(" {:01$}", d, flags.precision) + } else { + format!("{:01$}", d, flags.precision) + } + } + FormatOp::Octal => { + if flags.alternate { + // Leading octal zero counts against precision. + format!("0{:01$o}", d, flags.precision.saturating_sub(1)) + } else { + format!("{:01$o}", d, flags.precision) + } + } + FormatOp::LowerHex => { + if flags.alternate && d != 0 { + format!("0x{:01$x}", d, flags.precision) + } else { + format!("{:01$x}", d, flags.precision) + } + } + FormatOp::UpperHex => { + if flags.alternate && d != 0 { + format!("0X{:01$X}", d, flags.precision) + } else { + format!("{:01$X}", d, flags.precision) + } + } + FormatOp::String => return Err("non-number on stack with %s".to_string()), + } + .into_bytes() + } + Words(s) => match op { + FormatOp::String => { + let mut s = s.into_bytes(); + if flags.precision > 0 && flags.precision < s.len() { + s.truncate(flags.precision); + } + s + } + _ => return Err(format!("non-string on stack with %{}", op.to_char())), + }, + }; + if flags.width > s.len() { + let n = flags.width - s.len(); + if flags.left { + s.extend(repeat(b' ').take(n)); + } else { + let mut s_ = Vec::with_capacity(flags.width); + s_.extend(repeat(b' ').take(n)); + s_.extend(s.into_iter()); + s = s_; + } + } + Ok(s) +} |