mknod: use mode parsing in uucore

src/mknod/parsemode.rs

@@ -1,124 +1,23 @@
 extern crate libc;
 use libc::{mode_t, S_IRGRP, S_IWGRP, S_IROTH, S_IWOTH, S_IRUSR, S_IWUSR};
 
-fn parse_change(mode: &str, fperm: mode_t) -> (mode_t, usize) {
+use uucore::mode;
-    let mut srwx = fperm & 0o7000;
-    let mut pos = 0;
-    for ch in mode.chars() {
-        match ch {
-            'r' => srwx |= 0o444,
-            'w' => srwx |= 0o222,
-            'x' => srwx |= 0o111,
-            'X' => srwx |= 0o111,
-            's' => srwx |= 0o4000 | 0o2000,
-            't' => srwx |= 0o1000,
-            'u' => srwx = (fperm & 0o700) | ((fperm >> 3) & 0o070) | ((fperm >> 6) & 0o007),
-            'g' => srwx = ((fperm << 3) & 0o700) | (fperm & 0o070) | ((fperm >> 3) & 0o007),
-            'o' => srwx = ((fperm << 6) & 0o700) | ((fperm << 3) & 0o070) | (fperm & 0o007),
-            _ => break,
-        };
-        pos += 1;
-    }
-    if pos == 0 {
-        srwx = 0;
-    }
-    (srwx, pos)
-}
 
-fn parse_levels(mode: &str) -> (mode_t, usize) {
-    let mut mask = 0;
-    let mut pos = 0;
-    for ch in mode.chars() {
-        mask |= match ch {
-            'u' => 0o7700,
-            'g' => 0o7070,
-            'o' => 0o7007,
-            'a' => 0o7777,
-            _ => break,
-        };
-        pos += 1;
-    }
-    if pos == 0 {
-        mask = 0o7777;  // default to 'a'
-    }
-    (mask, pos)
-}
-
-fn parse_symbolic(mut fperm: mode_t, mut mode: &str) -> Result<mode_t, String> {
-    let (mask, pos) = parse_levels(mode);
-    if pos == mode.len() {
-        return Err("invalid mode".to_owned());
-    }
-    mode = &mode[pos..];
-    while mode.len() > 0 {
-        let (op, pos) = try!(parse_op(mode, None));
-        mode = &mode[pos..];
-        let (srwx, pos) = parse_change(mode, fperm);
-        mode = &mode[pos..];
-        match op {
-            '+' => fperm |= srwx & mask,
-            '-' => fperm &= !(srwx & mask),
-            '=' => fperm = (fperm & !mask) | (srwx & mask),
-            _ => unreachable!(),
-        }
-    }
-    Ok(fperm)
-}
-
-fn parse_op(mode: &str, default: Option<char>) -> Result<(char, usize), String> {
-    match mode.chars().next() {
-        Some(ch) => {
-            match ch {
-                '+' | '-' | '=' => Ok((ch, 1)),
-                _ => {
-                    match default {
-                        Some(ch) => Ok((ch, 0)),
-                        None => {
-                            Err(format!("invalid operator (expected +, -, or =, but found {})", ch))
-                        }
-                    }
-                }
-            }
-        }
-        None => Err("unexpected end of mode".to_owned()),
-    }
-}
-
-fn parse_numeric(fperm: mode_t, mut mode: &str) -> Result<mode_t, String> {
-    let (op, pos) = try!(parse_op(mode, Some('=')));
-    mode = mode[pos..].trim_left_matches('0');
-    match mode_t::from_str_radix(mode, 8) {
-        Ok(change) => {
-            let after = match op {
-                '+' => fperm | change,
-                '-' => fperm & !change,
-                '=' => change,
-                _ => unreachable!(),
-            };
-            if after > 0o7777 {
-                return Err("invalid mode".to_owned());
-            }
-            Ok(after)
-        }
-        Err(_) => Err("invalid mode".to_owned()),
-    }
-}
 pub fn parse_mode(mode: Option<String>) -> Result<mode_t, String> {
     let fperm = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
     if let Some(mode) = mode {
         let arr: &[char] = &['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'];
         let result = if mode.contains(arr) {
-            parse_numeric(fperm, mode.as_str())
+            mode::parse_numeric(fperm, mode.as_str())
         } else {
-            parse_symbolic(fperm, mode.as_str())
+            mode::parse_symbolic(fperm, mode.as_str(), true)
         };
-        result
+        result.map(|mode| mode as mode_t)
     } else {
         Ok(fperm)
     }
 }
 
-
 #[test]
 fn symbolic_modes() {
     assert_eq!(parse_mode(Some("u+x".to_owned())).unwrap(), 0o766);