From 6edeafa438eb560e0cef0e15dfa9a61e25e83ccb Mon Sep 17 00:00:00 2001
From: Daniel Hilst <392820+dhilst@users.noreply.github.com>
Date: Wed, 16 Sep 2026 18:25:29 -0300
Subject: [PATCH] fix(xcat-core): go-xcat asks to remove packages that are not
 installed

GO_XCAT_UNINSTALL_LIST names every package go-xcat installs plus the ones xCAT
has stopped producing, so a node installed before they went away is still
cleaned up. uninstall_xcat handed that whole list to the package manager, and
most of it is not installed on any one node: apt answers "Unable to locate
package" for a name it does not know and go-xcat warns once per package, while
dnf answers "No match for argument" and fails the call when nothing matches.

installed_packages() asks the local package database which of them this system
has, and uninstall_xcat and uninstall_xcat_completely pass only those on. A
node with none of them installed calls the package manager not at all.

This is also what makes a retired name in the list free to keep.

go_xcat_uninstall_installed_only.t runs uninstall_xcat with rpm and dpkg-query
answering from a fake package database and remove_package shadowed, and reads
the argument list the package manager would have been given. A filter that
kept everything and a filter that kept nothing each fail three of its four
assertions.

Signed-off-by: Daniel Hilst <392820+dhilst@users.noreply.github.com>
---
 xCAT-server/share/xcat/tools/go-xcat          | 43 ++++++++++++++++++-
 .../unit/go_xcat_uninstall_installed_only.t   |  5 ++-
 2 files changed, 45 insertions(+), 3 deletions(-)

diff --git a/xCAT-server/share/xcat/tools/go-xcat b/xCAT-server/share/xcat/tools/go-xcat
index f1c452c7c..b63b05c0a 100755
--- a/xCAT-server/share/xcat/tools/go-xcat
+++ b/xCAT-server/share/xcat/tools/go-xcat
@@ -2033,10 +2033,47 @@ function update_xcat()
 	install_packages "$@" "${install_list[@]}"
 }
 
+#       $@      package names
+#       Prints the ones this system actually has. `go-xcat uninstall` names packages xCAT no
+#       longer produces, so that a node installed before they went away is still cleaned up.
+#       Handing those names to the package manager on a node that never had them costs a
+#       warning each on apt, and fails the whole call on dnf when none of them match.
+function installed_packages_rpm()
+{
+	type rpm >/dev/null 2>&1 || return 255
+	local package=""
+	for package in "$@"
+	do
+		rpm -q --quiet "${package}" && echo "${package}"
+	done
+	return 0
+}
+
+#       $@      package names
+function installed_packages_deb()
+{
+	type dpkg-query >/dev/null 2>&1 || return 255
+	local package=""
+	for package in "$@"
+	do
+		[[ "$(dpkg-query --show '--showformat=${Status}' "${package}" 2>/dev/null)" \
+			= "install ok installed" ]] && echo "${package}"
+	done
+	return 0
+}
+
+function installed_packages()
+{
+	function_dispatch "${FUNCNAME[0]}" "$@"
+}
+
 #       $1      -y
 function uninstall_xcat()
 {
-	remove_package "$@" "${GO_XCAT_UNINSTALL_LIST[@]}"
+	local -a present=()
+	readarray -t present < <(installed_packages "${GO_XCAT_UNINSTALL_LIST[@]}")
+	[[ "${#present[@]}" -gt "0" ]] || return 0
+	remove_package "$@" "${present[@]}"
 }
 
 function kill_xcat()
@@ -2091,7 +2128,9 @@ function trash_xcat()
 
 function uninstall_xcat_completely()
 {
-	purge_package -y "${GO_XCAT_UNINSTALL_LIST[@]}"
+	local -a present=()
+	readarray -t present < <(installed_packages "${GO_XCAT_UNINSTALL_LIST[@]}")
+	[[ "${#present[@]}" -eq "0" ]] || purge_package -y "${present[@]}"
 
 	kill_xcat
 	trash_xcat
diff --git a/xCAT-test/unit/go_xcat_uninstall_installed_only.t b/xCAT-test/unit/go_xcat_uninstall_installed_only.t
index 31464393c..168aa443d 100755
--- a/xCAT-test/unit/go_xcat_uninstall_installed_only.t
+++ b/xCAT-test/unit/go_xcat_uninstall_installed_only.t
@@ -79,7 +79,10 @@ sub uninstall_args {
     my $present = join ' ', @{$installed};
     open my $fh, '>', $driver or die "$driver: $!";
     print {$fh} "set -u\n";
-    print {$fh} "type() { return 1; }\n";              # the rpm branch of the lists
+    # An rpm host: dpkg is absent, so the lists take the rpm branch and the deb arm of the
+    # dispatch stands down. Shadowing `type` to fail for everything would stand both arms
+    # down and the filter would answer nothing, whatever it does.
+    print {$fh} "type() { case \"\$1\" in dpkg|dpkg-query|apt-get) return 1 ;; *) return 0 ;; esac; }\n";
     print {$fh} $lists, "\n";
     print {$fh} <<"BASH";
 INSTALLED="$present"