Fix logcheck exit function

hack/tools/logcheck/main.go

@@ -102,7 +102,7 @@ func checkForFunctionExpr(fexpr *ast.CallExpr, pass *analysis.Pass, c *config) {
 			if !isUnstructured((fName)) {
 				// if format specifier is used, check for arg length will most probably fail
 				// so check for format specifier first and skip if found
-				if checkForFormatSpecifier(fexpr, pass) {
+				if checkForFormatSpecifier(fexpr, pass, c) {
 					return
 				}
 				if fName == "InfoS" {
@@ -179,11 +179,16 @@ func isKeysValid(keyValues []ast.Expr, fun ast.Expr, pass *analysis.Pass, funNam
 	}
 }
 
-func checkForFormatSpecifier(expr *ast.CallExpr, pass *analysis.Pass) bool {
+func checkForFormatSpecifier(expr *ast.CallExpr, pass *analysis.Pass, c *config) bool {
 	if selExpr, ok := expr.Fun.(*ast.SelectorExpr); ok {
 		// extracting function Name like Infof
 		fName := selExpr.Sel.Name
-		if specifier, found := hasFormatSpecifier(expr.Args); found {
+		specifier, found := hasFormatSpecifier(expr.Args)
+		if found {
+			if (fName == "Exit" || fName ==  "Exitf" || fName == "Exitln" || fName == "ExitDepth") && c.allowUnstructured {
+				return true
+			}
+
 			msg := fmt.Sprintf("structured logging function %q should not use format specifier %q", fName, specifier)
 			pass.Report(analysis.Diagnostic{
 				Pos:     expr.Fun.Pos(),

hack/tools/logcheck/testdata/src/allowUnstructuredLogs/allowUnstructuredLogs.go

@@ -41,6 +41,13 @@ func allowUnstructuredLogs() {
 	klog.ErrorS(nil, "Starting container in a pod", testKey, "containerID") // want `Key positional arguments are expected to be inlined constant strings. `
 	klog.InfoS("test: %s", "testname")                                      // want `structured logging function "InfoS" should not use format specifier "%s"`
 	klog.ErrorS(nil, "test no.: %d", 1)                                     // want `structured logging function "ErrorS" should not use format specifier "%d"`
+	klog.Exit("test log")
+	klog.Exit("test: %s", "log")
+	klog.ExitDepth(1, "test log")
+	klog.ExitDepth(1, "test: %s", "log")
+	klog.Exitln("test log")
+	klog.Exitln("test: %s", "log")
+	klog.Exitf("%s", "test log")
 
 	// Unstructured logs
 	// Error is not expected as this package allows unstructured logging

hack/tools/logcheck/testdata/src/doNotAllowUnstructuredLogs/doNotAllowUnstructuredLogs.go

@@ -41,6 +41,10 @@ func doNotAllowUnstructuredLogs() {
 	klog.ErrorS(nil, "Starting container in a pod", testKey, "containerID") // want `Key positional arguments are expected to be inlined constant strings. `
 	klog.InfoS("test: %s", "testname")                                      // want `structured logging function "InfoS" should not use format specifier "%s"`
 	klog.ErrorS(nil, "test no.: %d", 1)                                     // want `structured logging function "ErrorS" should not use format specifier "%d"`
+	klog.Exit("test log")
+	klog.ExitDepth(1, "test log")
+	klog.Exitln("test log")
+	klog.Exitf("test log")
 
 	// Unstructured logs
 	// Error is expected as this package does not allow unstructured logging

hack/tools/logcheck/testdata/src/k8s.io/klog/v2/klog.go

@@ -180,3 +180,20 @@ func Fatalln(args ...interface{}) {
 // Arguments are handled in the manner of fmt.Printf; a newline is appended if missing.
 func Fatalf(format string, args ...interface{}) {
 }
+
+func Exit(args ...interface{}) {
+}
+
+// ExitDepth acts as Exit but uses depth to determine which call frame to log.
+// ExitDepth(0, "msg") is the same as Exit("msg").
+func ExitDepth(depth int, args ...interface{}) {
+}
+
+// Exitln logs to the FATAL, ERROR, WARNING, and INFO logs, then calls os.Exit(1).
+func Exitln(args ...interface{}) {
+}
+
+// Exitf logs to the FATAL, ERROR, WARNING, and INFO logs, then calls os.Exit(1).
+// Arguments are handled in the manner of fmt.Printf; a newline is appended if missing.
+func Exitf(format string, args ...interface{}) {
+}