ls: Don't call the capabilites features of the system when passed an empty ca=

in LS_COLORS

In parallel, in the GNU test, adjust the GNU tests as we don't use libcap
but xattr instead.

Author: sylvestre

.vscode/cspell.dictionaries/jargon.wordlist.txt

@@ -10,6 +10,7 @@ bytewise
 canonicalization
 canonicalize
 canonicalizing
+capget
 codepoint
 codepoints
 codegen
@@ -65,6 +66,7 @@ kibi
 kibibytes
 libacl
 lcase
+llistxattr
 lossily
 lstat
 mebi
@@ -108,6 +110,7 @@ seedable
 semver
 semiprime
 semiprimes
+setcap
 setfacl
 shortcode
 shortcodes

src/uu/ls/src/colors.rs

@@ -156,19 +156,23 @@ pub(crate) fn color_name(
     target_symlink: Option<&PathData>,
     wrap: bool,
 ) -> String {
-    #[cfg(any(not(unix), target_os = "android", target_os = "macos"))]
-    let has_capabilities = false;
-    #[cfg(all(unix, not(any(target_os = "android", target_os = "macos"))))]
     // Check if the file has capabilities
-    let has_capabilities = uucore::fsxattr::has_acl(path.p_buf.as_path());
-
-    // If the file has capabilities, use a specific style for `ca` (capabilities)
-    if has_capabilities {
-        if let Some(style) = style_manager
+    #[cfg(all(unix, not(any(target_os = "android", target_os = "macos"))))]
+    {
+        // Skip checking capabilities if LS_COLORS=ca=:
+        let capabilities = style_manager
             .colors
-            .style_for_indicator(Indicator::Capabilities)
-        {
-            return style_manager.apply_style(Some(style), name, wrap);
+            .style_for_indicator(Indicator::Capabilities);
+
+        let has_capabilities = if capabilities.is_none() {
+            false
+        } else {
+            uucore::fsxattr::has_acl(path.p_buf.as_path())
+        };
+
+        // If the file has capabilities, use a specific style for `ca` (capabilities)
+        if has_capabilities {
+            return style_manager.apply_style(capabilities, name, wrap);
         }
     }
 

util/gnu-patches/tests_ls_no_cap.patch

@@ -0,0 +1,22 @@
+diff --git a/tests/ls/no-cap.sh b/tests/ls/no-cap.sh
+index 3d84c74ff..d1f60e70a 100755
+--- a/tests/ls/no-cap.sh
++++ b/tests/ls/no-cap.sh
+@@ -21,13 +21,13 @@ print_ver_ ls
+ require_strace_ capget
+ 
+ LS_COLORS=ca=1; export LS_COLORS
+-strace -e capget ls --color=always > /dev/null 2> out || fail=1
+-$EGREP 'capget\(' out || skip_ "your ls doesn't call capget"
++strace -e llistxattr ls --color=always > /dev/null 2> out || fail=1
++$EGREP 'llistxattr\(' out || skip_ "your ls doesn't call llistxattr"
+ 
+ rm -f out
+ 
+ LS_COLORS=ca=:; export LS_COLORS
+-strace -e capget ls --color=always > /dev/null 2> out || fail=1
+-$EGREP 'capget\(' out && fail=1
++strace -e llistxattr ls --color=always > /dev/null 2> out || fail=1
++$EGREP 'llistxattr\(' out && fail=1
+ 
+ Exit $fail