[PATCH 2/4] scripts/kernel-doc: avoid error_count overflows

[Mauro Carvalho Chehab <mchehab+huawei@kernel.org>]

The glibc library limits the return code to 8 bits. We need to
stick to this limit when using sys.exit(error_count).

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
---
 scripts/kernel-doc.py | 32 ++++++++++++++++++++++----------
 1 file changed, 22 insertions(+), 10 deletions(-)

diff --git a/scripts/kernel-doc.py b/scripts/kernel-doc.py
index 7a1eaf986bcd..600bdfea6a96 100755
--- a/scripts/kernel-doc.py
+++ b/scripts/kernel-doc.py
@@ -176,7 +176,14 @@ class MsgFormatter(logging.Formatter):
         return logging.Formatter.format(self, record)
 
 def main():
-    """Main program"""
+    """
+    Main program
+    By default, the return value is zero on parsing errors or when the
+    Python version is not compatible with kernel-doc. The rationale is
+    to not break Linux compilation on such cases.
+    If -Werror is used, it will return the number of parse errors, up to
+    255 errors, as this is the maximum value allowed by glibc.
+    """
 
     parser = argparse.ArgumentParser(formatter_class=argparse.RawTextHelpFormatter,
                                      description=DESC)
@@ -321,18 +328,23 @@ def main():
     if not error_count:
         sys.exit(0)
 
+    if args.verbose:
+        print("%s errors" % error_count)                # pylint: disable=C0209
+
+
     if args.werror:
         print("%s warnings as errors" % error_count)    # pylint: disable=C0209
+
+        #
+        # Return code is 8-bits, as seen at:
+        #   https://www.gnu.org/software/libc/manual/html_node/Exit-Status.html
+        # Truncate to avoid overflow
+        #
+        if error_count > 255:
+            error_count = 255
+
         sys.exit(error_count)
-
-    if args.verbose:
-        print("%s errors" % error_count)                # pylint: disable=C0209
-
-    if args.none:
-        sys.exit(0)
-
-    sys.exit(error_count)
-
+    sys.exit(0)
 
 # Call main method
 if __name__ == "__main__":
-- 
2.52.0