Move binary check into variable

Author: ardaguclu

pkg/cli/admin/mustgather/mustgather.go

@@ -99,7 +99,7 @@ usage_percentage=$(df -P "$target_dir" | awk 'NR==2 {print $5}' | sed 's/%%//')
 echo "[disk usage checker] Volume usage percentage: current = ${usage_percentage} ; allowed = ${usage_percentage_limit}"
 if [ "$usage_percentage" -gt "$usage_percentage_limit" ]; then
 	echo "[disk usage checker] Disk usage exceeds the volume percentage of ${usage_percentage_limit} for mounted directory, terminating..."
-	if command -v setsid >/dev/null 2>&1 && command -v ps >/dev/null 2>&1 && command -v pkill >/dev/null 2>&1; then
+	if [ "$HAVE_SESSION_TOOLS" = "true" ]; then
 		ps -o sess --no-headers | sort -u | while read sid; do
 			[[ "$sid" -eq "${$}" ]] && continue
 			pkill --signal SIGKILL --session "$sid"
@@ -1325,14 +1325,21 @@ func buildPodCommand(
 ) string {
 	var cmd strings.Builder
 
+	// Check if session management tools are available once and store in a variable.
+	cmd.WriteString("if command -v setsid >/dev/null 2>&1 && command -v ps >/dev/null 2>&1 && command -v pkill >/dev/null 2>&1; then\n")
+	cmd.WriteString("  HAVE_SESSION_TOOLS=true\n")
+	cmd.WriteString("else\n")
+	cmd.WriteString("  HAVE_SESSION_TOOLS=false\n")
+	cmd.WriteString("fi\n\n")
+
 	// Start the checker in the background.
 	cmd.WriteString(volumeCheckerScript)
 	cmd.WriteString(` & `)
 
 	// Start the gather command in a separate session if setsid, ps, and pkill are available.
 	// Fall back to simpler approach if any of these tools are not present (minimal images).
-	cmd.WriteString("if command -v setsid >/dev/null 2>&1 && command -v ps >/dev/null 2>&1 && command -v pkill >/dev/null 2>&1; then\n")
-	cmd.WriteString("  setsid -w bash <<-MUSTGATHER_EOF\n")
+	cmd.WriteString(`if [ "$HAVE_SESSION_TOOLS" = "true" ]; then`)
+	cmd.WriteString("\n  setsid -w bash <<-MUSTGATHER_EOF\n")
 	cmd.WriteString(gatherCommand)
 	cmd.WriteString("\nMUSTGATHER_EOF\n")
 	cmd.WriteString("else\n")