Read setuid/setgid/sticky bits

The problem here was that we were using `metadata.permissions().mode()`, which is capped at 0o777, rather than `metadata.mode()`, which exposes every bit. With this change, we can access the higher-order permission bits, and put them in the Permissions struct.

src/fs/fields.rs

@@ -67,6 +67,10 @@ pub struct Permissions {
     pub other_read:     bool,
     pub other_write:    bool,
     pub other_execute:  bool,
+
+    pub sticky:         bool,
+    pub setgid:         bool,
+    pub setuid:         bool,
 }
 
 /// The three pieces of information that are displayed as a single column in

src/fs/file.rs

@@ -309,19 +309,25 @@ impl<'dir> File<'dir> {
 
     /// This file’s permissions, with flags for each bit.
     pub fn permissions(&self) -> f::Permissions {
-        let bits = self.metadata.permissions().mode();
+        let bits = self.metadata.mode();
         let has_bit = |bit| { bits & bit == bit };
 
         f::Permissions {
             user_read:      has_bit(modes::USER_READ),
             user_write:     has_bit(modes::USER_WRITE),
             user_execute:   has_bit(modes::USER_EXECUTE),
+
             group_read:     has_bit(modes::GROUP_READ),
             group_write:    has_bit(modes::GROUP_WRITE),
             group_execute:  has_bit(modes::GROUP_EXECUTE),
+
             other_read:     has_bit(modes::OTHER_READ),
             other_write:    has_bit(modes::OTHER_WRITE),
             other_execute:  has_bit(modes::OTHER_EXECUTE),
+
+            sticky:         has_bit(modes::STICKY),
+            setgid:         has_bit(modes::SETGID),
+            setuid:         has_bit(modes::SETUID),
         }
     }
 
@@ -437,12 +443,18 @@ mod modes {
     pub const USER_READ: Mode     = libc::S_IRUSR as Mode;
     pub const USER_WRITE: Mode    = libc::S_IWUSR as Mode;
     pub const USER_EXECUTE: Mode  = libc::S_IXUSR as Mode;
+
     pub const GROUP_READ: Mode    = libc::S_IRGRP as Mode;
     pub const GROUP_WRITE: Mode   = libc::S_IWGRP as Mode;
     pub const GROUP_EXECUTE: Mode = libc::S_IXGRP as Mode;
+
     pub const OTHER_READ: Mode    = libc::S_IROTH as Mode;
     pub const OTHER_WRITE: Mode   = libc::S_IWOTH as Mode;
     pub const OTHER_EXECUTE: Mode = libc::S_IXOTH as Mode;
+
+    pub const STICKY: Mode        = libc::S_ISVTX as Mode;
+    pub const SETGID: Mode        = libc::S_ISGID as Mode;
+    pub const SETUID: Mode        = libc::S_ISUID as Mode;
 }
 
 

src/output/render/permissions.rs

@@ -79,9 +79,9 @@ pub mod test {
         details.colours.punctuation = Fixed(44).normal();
 
         let bits = f::Permissions {
-            user_read:  false,  user_write:  false,  user_execute:  false,
-            group_read: false,  group_write: false,  group_execute: false,
-            other_read: false,  other_write: false,  other_execute: false,
+            user_read:  false,  user_write:  false,  user_execute:  false,  setuid: false,
+            group_read: false,  group_write: false,  group_execute: false,  setgid: false,
+            other_read: false,  other_write: false,  other_execute: false,  sticky: false,
         };
 
         let expected = TextCellContents::from(vec![
@@ -109,9 +109,9 @@ pub mod test {
         details.colours.perms.other_execute = Fixed(109).normal();
 
         let bits = f::Permissions {
-            user_read:  true,  user_write:  true,  user_execute:  true,
-            group_read: true,  group_write: true,  group_execute: true,
-            other_read: true,  other_write: true,  other_execute: true,
+            user_read:  true,  user_write:  true,  user_execute:  true,  setuid: false,
+            group_read: true,  group_write: true,  group_execute: true,  setgid: false,
+            other_read: true,  other_write: true,  other_execute: true,  sticky: false,
         };
 
         let expected = TextCellContents::from(vec![