check_whitespace: Enforce an 80 column limit on source code

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

scripts/check_whitespace.py

@@ -27,6 +27,7 @@ def check_file(filename):
         # Empty files are okay
         return
     # Do checks
+    is_source_code = any([filename.endswith(s) for s in ['.c', '.h', '.py']])
     lineno = 0
     for lineno, line in enumerate(data.split('\n')):
         # Verify line is valid utf-8
@@ -49,6 +50,9 @@ def check_file(filename):
         # Check for trailing space
         if line.endswith(' '):
             report_error(filename, lineno, "Line has trailing spaces")
+        # Check for more than 80 characters
+        if is_source_code and len(line) > 80:
+            report_error(filename, lineno, "Line longer than 80 characters")
     if not data.endswith('\n'):
         report_error(filename, lineno, "No newline at end of file")
     if data.endswith('\n\n'):