docs: kdoc: Add some comments to process_decl()

Now that the function can actually fit into a human brain, add a few
comments.  While I was at it, I switched to the trim_whitespace() helper
rather than open-coding it.

Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250621203512.223189-9-corbet@lwn.net

diff --git a/scripts/lib/kdoc/kdoc_parser.py b/scripts/lib/kdoc/kdoc_parser.py
index f7a5b85a8ed70c3f736fff70dcb6102569b5d395..a6ee8bac378db92a137815ac0345ee150e95c1d2 100644 (file)
--- a/scripts/lib/kdoc/kdoc_parser.py
+++ b/scripts/lib/kdoc/kdoc_parser.py
@@ -1377,26 +1377,28 @@ class KernelDoc:
         """
         if self.is_new_section(ln, line) or self.is_comment_end(ln, line):
             return
-
+        #
+        # Look for anything with the " * " line beginning.
+        #
         if doc_content.search(line):
             cont = doc_content.group(1)
-
+            #
+            # A blank line means that we have moved out of the declaration
+            # part of the comment (without any "special section" parameter
+            # descriptions).
+            #
             if cont == "":
                 self.state = state.BODY
                 self.entry.contents += "\n"  # needed?
-
+            #
+            # Otherwise we have more of the declaration section to soak up.
+            #
             else:
-                # Continued declaration purpose
-                self.entry.declaration_purpose = self.entry.declaration_purpose.rstrip()
-                self.entry.declaration_purpose += " " + cont
-
-                r = KernRe(r"\s+")
-                self.entry.declaration_purpose = r.sub(' ',
-                                                       self.entry.declaration_purpose)
-            return
-
-        # Unknown line, ignore
-        self.emit_msg(ln, f"bad line: {line}")
+                self.entry.declaration_purpose = \
+                    trim_whitespace(self.entry.declaration_purpose + ' ' + cont)
+        else:
+            # Unknown line, ignore
+            self.emit_msg(ln, f"bad line: {line}")
 
 
     def process_special(self, ln, line):