Support restyling only the specified files

Signed-off-by: Gilles Peskine <[email protected]>

scripts/code_style.py

@@ -163,14 +163,26 @@ def main() -> int:
                 + uncrustify_version + "' (Note: The only supported version" \
                 "is " + UNCRUSTIFY_SUPPORTED_VERSION + ")", file=STDOUT_UTF8)
 
-    src_files = get_src_files()
-
     parser = argparse.ArgumentParser()
-    parser.add_argument('-f', '--fix', action='store_true', \
-            help='modify source files to fix the code style')
+    parser.add_argument('-f', '--fix', action='store_true',
+                        help='modify source files to fix the code style')
+    # --files is almost useless: it only matters if there are no files
+    # ('code_style.py' without arguments checks all files known to Git,
+    # 'code_style.py --files' does nothing). 'code_style.py --files ...' is
+    # intended as a stable ("porcelain") way to restyle a possibly empty
+    # set of files.
+    parser.add_argument('--files', action='store_true',
+                        help='only check the specified files (default with non-option arguments)')
+    parser.add_argument('operands', nargs='*', metavar='FILE',
+                        help='files to check (if none: check files that are known to git)')
 
     args = parser.parse_args()
 
+    if args.files or args.operands:
+        src_files = args.operands
+    else:
+        src_files = get_src_files()
+
     if args.fix:
         # Fix mode
         return fix_style(src_files)