diff --git a/src/tools/systemd.rs b/src/tools/systemd.rs index 9ce65bcd..20088f80 100644 --- a/src/tools/systemd.rs +++ b/src/tools/systemd.rs @@ -4,3 +4,71 @@ pub mod config; mod parse_time; pub mod tm_editor; pub mod time; + +use anyhow::{bail, Error}; + +/// Escape strings for usage in systemd unit names +pub fn escape_unit(mut unit: &str, is_path: bool) -> String { + + if is_path { + unit = unit.trim_matches('/'); + if unit.is_empty() { + return String::from("-"); + } + } + + let unit = unit.as_bytes(); + + let mut escaped = String::new(); + + for (i, c) in unit.iter().enumerate() { + if *c == b'/' { + escaped.push('-'); + continue; + } + if (i == 0 && *c == b'.') || !((*c >= b'0' && *c <= b'9') || (*c >= b'A' && *c <= b'Z') || (*c >= b'a' && *c <= b'z')) { + escaped.push_str(&format!("\\x{:0x}", c)); + } else { + escaped.push(*c as char); + } + } + escaped +} + +fn parse_hex_digit(d: u8) -> Result { + if d >= b'0' && d <= b'9' { return Ok(d - b'0'); } + if d >= b'A' && d <= b'F' { return Ok(d - b'A' + 10); } + if d >= b'a' && d <= b'f' { return Ok(d - b'a' + 10); } + bail!("got invalid hex digit"); +} + +/// Unescape strings used in systemd unit names +pub fn unescape_unit(text: &str) -> Result { + + let mut i = text.as_bytes(); + + let mut data: Vec = Vec::new(); + + loop { + if i.is_empty() { break; } + let next = i[0]; + if next == b'\\' { + if i.len() < 4 { bail!("short input"); } + if i[1] != b'x' { bail!("unkwnown escape sequence"); } + let h1 = parse_hex_digit(i[2])?; + let h0 = parse_hex_digit(i[3])?; + data.push(h1<<4|h0); + i = &i[4..] + } else if next == b'-' { + data.push(b'/'); + i = &i[1..] + } else { + data.push(next); + i = &i[1..] + } + } + + let text = String::from_utf8(data)?; + + Ok(text) +}