From 528d2478cde67016b604871a09479f61c6e26cbe Mon Sep 17 00:00:00 2001
From: Nathan Fisher <jeang3nie@hitchhiker-linux.org>
Date: Mon, 16 Jan 2023 16:22:29 -0500
Subject: [PATCH] mode::Parser - made self.who into u32 and test using bitflags

---
 src/mode/parser.rs | 104 +++++++++++++++++++++++----------------------
 1 file changed, 53 insertions(+), 51 deletions(-)

diff --git a/src/mode/parser.rs b/src/mode/parser.rs
index af59e70..2864d63 100644
--- a/src/mode/parser.rs
+++ b/src/mode/parser.rs
@@ -33,15 +33,15 @@ enum Op {
 
 #[derive(Clone, Debug, PartialEq)]
 enum Who {
-    User,
-    Group,
-    Other,
+    User = 0o100,
+    Group = 0o10,
+    Other = 0o1,
 }
 
 pub struct Parser {
     mode: u32,
     op: Option<Op>,
-    who: Vec<Who>,
+    who: u32,
     bits: Vec<Bit>,
 }
 
@@ -53,7 +53,7 @@ impl Default for Parser {
         Self {
             mode,
             op: None,
-            who: vec![],
+            who: 0,
             bits: vec![],
         }
     }
@@ -64,7 +64,7 @@ impl Parser {
         Self {
             mode,
             op: None,
-            who: vec![],
+            who: 0,
             bits: vec![],
         }
     }
@@ -79,10 +79,10 @@ impl Parser {
     }
 
     fn add_who(&mut self, who: Who) -> Result<(), ParseError> {
-        if self.op.is_some() || self.who.contains(&who) || !self.bits.is_empty() {
+        if self.op.is_some() || !self.bits.is_empty() {
             Err(ParseError::InvalidDigit)
         } else {
-            self.who.push(who);
+            self.who |= who as u32;
             Ok(())
         }
     }
@@ -97,61 +97,63 @@ impl Parser {
     }
 
     fn push_read_bits(&mut self) -> Result<(), ParseError> {
-        for w in &self.who {
-            match w {
-                Who::User => self.bits.push(Bit::URead),
-                Who::Group => self.bits.push(Bit::GRead),
-                Who::Other => self.bits.push(Bit::ORead),
-            }
+        if self.who & 0o100 != 0 {
+            self.bits.push(Bit::URead);
+        }
+        if self.who & 0o10 != 0 {
+            self.bits.push(Bit::GRead);
+        }
+        if self.who & 0o1 != 0 {
+            self.bits.push(Bit::ORead);
         }
         Ok(())
     }
 
     fn push_write_bits(&mut self) -> Result<(), ParseError> {
-        for w in &self.who {
-            match w {
-                Who::User => self.bits.push(Bit::UWrite),
-                Who::Group => self.bits.push(Bit::GWrite),
-                Who::Other => self.bits.push(Bit::OWrite),
-            }
+        if self.who & 0o100 != 0 {
+            self.bits.push(Bit::UWrite);
+        }
+        if self.who & 0o10 != 0 {
+            self.bits.push(Bit::GWrite);
+        }
+        if self.who & 0o1 != 0 {
+            self.bits.push(Bit::OWrite);
         }
         Ok(())
     }
 
     fn push_exec_bits(&mut self) -> Result<(), ParseError> {
-        for w in &self.who {
-            match w {
-                Who::User => self.bits.push(Bit::UExec),
-                Who::Group => self.bits.push(Bit::GExec),
-                Who::Other => self.bits.push(Bit::OExec),
-            }
+        if self.who & 0o100 != 0 {
+            self.bits.push(Bit::UExec);
+        }
+        if self.who & 0o10 != 0 {
+            self.bits.push(Bit::GExec);
+        }
+        if self.who & 0o1 != 0 {
+            self.bits.push(Bit::OExec);
         }
         Ok(())
     }
 
     fn push_suid_sgid(&mut self) -> Result<(), ParseError> {
-        if self.who.is_empty() {
+        if self.who == 0 || self.who & 0o1 != 0{
             return Err(ParseError::InvalidBit);
         }
-        for w in &self.who {
-            match w {
-                &Who::Other => return Err(ParseError::InvalidBit),
-                &Who::User => self.bits.push(Bit::Suid),
-                &Who::Group => self.bits.push(Bit::Sgid),
-            }
+        if self.who & 0o100 != 0 {
+            self.bits.push(Bit::Suid);
+        }
+        if self.who &0o10 != 0 {
+            self.bits.push(Bit::Sgid);
         }
         Ok(())
     }
 
     fn push_sticky(&mut self) -> Result<(), ParseError> {
-        if self.who.is_empty() {
+        if self.who == 0 || self.who & 0o100 != 0 || self.who & 0o10 != 0 {
             return Err(ParseError::InvalidBit);
         }
-        for w in &self.who {
-            match w {
-                &Who::User | &Who::Group => return Err(ParseError::InvalidBit),
-                &Who::Other => self.bits.push(Bit::Sticky),
-            }
+        if self.who & 0o1 != 0 {
+            self.bits.push(Bit::Sticky);
         }
         Ok(())
     }
@@ -173,12 +175,14 @@ impl Parser {
             Some(Op::Add) => self.add_bits(),
             Some(Op::Remove) => self.remove_bits(),
             Some(Op::Equals) => {
-                for w in &self.who {
-                    match w {
-                        Who::User => self.mode &= !0o4444,
-                        Who::Group => self.mode &= !0o2222,
-                        Who::Other => self.mode &= !0o1111,
-                    }
+                if self.who & 0o100 != 0 {
+                    self.mode &= 0o4444;
+                }
+                if self.who & 0o10 != 0 {
+                    self.mode &= 0o2222;
+                }
+                if self.who &0o1 != 0 {
+                    self.mode &= 0o1111;
                 }
                 self.add_bits();
             },
@@ -188,7 +192,7 @@ impl Parser {
     }
 
     fn reset(&mut self) {
-        self.who.clear();
+        self.who = 0;
         self.op = None;
         self.bits.clear();
     }
@@ -228,10 +232,8 @@ impl Parser {
                 _ => return Err(ParseError::InvalidDigit),
             }
         }
-        if self.who.is_empty() {
-            self.who.push(Who::User);
-            self.who.push(Who::Group);
-            self.who.push(Who::Other);
+        if self.who == 0 {
+            self.who |= 0o111;
         }
         self.set_bits()?;
         self.reset();
@@ -240,7 +242,7 @@ impl Parser {
 
     pub fn parse_all(&mut self, value: &str) -> Result<u32, ParseError> {
         for seg in value.split(',') {
-            self.parse(seg);
+            let _mode = self.parse(seg);
         }
         Ok(self.mode())
     }