code_size_compare: add logging module and tweak prompt message

Signed-off-by: Yanray Wang <yanray.wang@arm.com>

scripts/mbedtls_dev/logging_util.py

@@ -0,0 +1,55 @@
+"""Auxiliary functions used for logging module.
+"""
+
+# Copyright The Mbed TLS Contributors
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+import sys
+
+def configure_logger(
+        logger: logging.Logger,
+        logger_format="[%(levelname)s]: %(message)s"
+    ) -> None:
+    """
+    Configure the logging.Logger instance so that:
+        - Format is set to any logger_format.
+            Default: "[%(levelname)s]: %(message)s"
+        - loglevel >= WARNING are printed to stderr.
+        - loglevel <  WARNING are printed to stdout.
+    """
+    class MaxLevelFilter(logging.Filter):
+        # pylint: disable=too-few-public-methods
+        def __init__(self, max_level, name=''):
+            super().__init__(name)
+            self.max_level = max_level
+
+        def filter(self, record: logging.LogRecord) -> bool:
+            return record.levelno <= self.max_level
+
+    log_formatter = logging.Formatter(logger_format)
+
+    # set loglevel >= WARNING to be printed to stderr
+    stderr_hdlr = logging.StreamHandler(sys.stderr)
+    stderr_hdlr.setLevel(logging.WARNING)
+    stderr_hdlr.setFormatter(log_formatter)
+
+    # set loglevel <= INFO to be printed to stdout
+    stdout_hdlr = logging.StreamHandler(sys.stdout)
+    stdout_hdlr.addFilter(MaxLevelFilter(logging.INFO))
+    stdout_hdlr.setFormatter(log_formatter)
+
+    logger.addHandler(stderr_hdlr)
+    logger.addHandler(stdout_hdlr)