1 files changed, 68 insertions, 0 deletions
diff --git a/src/lib/log/log_formatter.cc b/src/lib/log/log_formatter.cc
new file mode 100644
index 0000000..1ce33f4
--- /dev/null
+++ b/src/lib/log/log_formatter.cc
@@ -0,0 +1,68 @@
+// Copyright (C) 2011-2022 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#include <config.h>
+#include <log/log_formatter.h>
+
+#include <cassert>
+
+#ifdef ENABLE_LOGGER_CHECKS
+#include <iostream>
+#endif
+
+using namespace std;
+using namespace boost;
+
+namespace isc {
+namespace log {
+
+void
+replacePlaceholder(std::string& message, const string& arg,
+                   const unsigned placeholder) {
+    const string mark("%" + lexical_cast<string>(placeholder));
+    size_t pos(message.find(mark));
+    if (pos != string::npos) {
+        do {
+            message.replace(pos, mark.size(), arg);
+            pos = message.find(mark, pos + arg.size());
+        } while (pos != string::npos);
+    } else {
+#ifdef ENABLE_LOGGER_CHECKS
+        // We're missing the placeholder, so throw an exception
+        isc_throw(MismatchedPlaceholders, "Missing logger placeholder '" << mark << "' for value '"
+                                                                         << arg << "' in message '"
+                                                                         << message << "'");
+#else
+        // We're missing the placeholder, so add some complain
+        message.append(" @@Missing logger placeholder '" + mark + "' for value '" + arg + "'@@");
+#endif /* ENABLE_LOGGER_CHECKS */
+    }
+}
+
+void
+checkExcessPlaceholders(std::string& message,
+                        unsigned int placeholder) {
+    const string mark("%" + lexical_cast<string>(placeholder));
+    const size_t pos(message.find(mark));
+    if (pos != string::npos) {
+        // Excess placeholders were found.  If we enable the harsh check,
+        // abort it.  Note: ideally we'd like to throw MismatchedPlaceholders,
+        // but we can't at least for now because this function is called from
+        // the Formatter's destructor.
+#ifdef ENABLE_LOGGER_CHECKS
+        // Also, make sure we print the message so we can identify which
+        // identifier has the problem.
+        cerr << "Excess logger placeholder '" << mark << "' still exists in message '" << message
+             << "'." << endl;
+        assert(false);
+#else
+        message.append(" @@Excess logger placeholder '" + mark + "' still exists@@");
+#endif /* ENABLE_LOGGER_CHECKS */
+    }
+}
+
+} // namespace log
+} // namespace isc