Import of the watch repository from Pebble

waftools/insert_text_section_crc.py

@@ -0,0 +1,60 @@
+#!/usr/bin/env python
+# Copyright 2024 Google LLC
+#
+# 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.
+
+
+from waflib import Logs
+from zlib import crc32
+from shutil import copyfile
+import struct
+from elftools.elf.elffile import ELFFile
+
+TEXT_SECTION_NAME = ".text"
+TEXT_CRC32_SECTION_NAME = ".text_crc32"
+
+def wafrule(task):
+    in_file = task.inputs[0].abspath()
+    out_file = task.outputs[0].abspath()
+
+    text_data = get_text_section_data_from_file(in_file)
+    if not text_data:
+        error = 'Unable to get {} section from {}'.format(TEXT_SECTION_NAME, in_file)
+        Logs.pprint('RED', error)
+        return error
+
+    crc = crc32(text_data) & 0xFFFFFFFF
+
+    offset = get_text_crc32_section_offset_from_file(in_file)
+    if not offset:
+        error = 'Unable to get {} section from {}'.format(TEXT_CRC32_SECTION_NAME, in_file)
+        Logs.pprint('RED', error)
+        return error
+
+    copyfile(in_file, out_file)
+
+    with open(out_file, 'rb+') as file:
+        file.seek(offset)
+        file.write(struct.pack('<I', crc))
+
+
+def get_text_section_data_from_file(filename):
+    with open(filename, 'rb') as file:
+        section = ELFFile(file).get_section_by_name(TEXT_SECTION_NAME)
+        return section.data() if section is not None else None
+
+def get_text_crc32_section_offset_from_file(filename):
+    with open(filename, 'rb') as file:
+        section = ELFFile(file).get_section_by_name(TEXT_CRC32_SECTION_NAME)
+        return section['sh_offset'] if section is not None else None
+