docs: kdoc: rework the handling of SPECIAL_SECTION

Move the recognition of this state to when we enter it, rather than when we
exit, eliminating some twisty logic along the way.

Some changes in output do result from this shift, generally for kerneldoc
comments that do not quite fit the format.  See, for example,
struct irqdomain.  As far as I can tell, the new behavior is more correct
in each case.

Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250621203512.223189-7-corbet@lwn.net

1 files changed, 20 insertions, 28 deletions

diff --git a/scripts/lib/kdoc/kdoc_parser.py b/scripts/lib/kdoc/kdoc_parser.py
index a336d543e72b..5998b02ca3a0 100644
--- a/scripts/lib/kdoc/kdoc_parser.py
+++ b/scripts/lib/kdoc/kdoc_parser.py
@@ -1316,21 +1316,25 @@ class KernelDoc:
     def is_new_section(self, ln, line):
         if doc_sect.search(line):
             self.entry.in_doc_sect = True
+            self.state = state.BODY
+            #
+            # Pick out the name of our new section, tweaking it if need be.
+            #
             newsection = doc_sect.group(1)
-
-            if newsection.lower() in ["description", "context"]:
-                newsection = newsection.title()
-
-            # Special case: @return is a section, not a param description
-            if newsection.lower() in ["@return", "@returns",
-                                      "return", "returns"]:
+            if newsection.lower() == 'description':
+                newsection = 'Description'
+            elif newsection.lower() == 'context':
+                newsection = 'Context'
+                self.state = state.SPECIAL_SECTION
+            elif newsection.lower() in ["@return", "@returns",
+                                        "return", "returns"]:
                 newsection = "Return"
-
-            # Perl kernel-doc has a check here for contents before sections.
-            # the logic there is always false, as in_doc_sect variable is
-            # always true. So, just don't implement Wcontents_before_sections
-
-            # .title()
+                self.state = state.SPECIAL_SECTION
+            elif newsection[0] == '@':
+                self.state = state.SPECIAL_SECTION
+            #
+            # Initialize the contents, and get the new section going.
+            #
             newcontents = doc_sect.group(2)
             if not newcontents:
                 newcontents = ""
@@ -1344,8 +1348,6 @@ class KernelDoc:
             self.entry.contents = newcontents.lstrip()
             if self.entry.contents:
                 self.entry.contents += "\n"
-
-            self.state = state.BODY
             return True
         return False
 
@@ -1395,8 +1397,9 @@ class KernelDoc:
         """
         STATE_SPECIAL_SECTION: a section ending with a blank line
         """
-        if KernRe(r"\s*\*\s*\S").match(line):
+        if KernRe(r"\s*\*\s*$").match(line):
             self.entry.begin_section(ln, dump = True)
+            self.state = state.BODY
         self.process_body(ln, line)
 
     def process_body(self, ln, line):
@@ -1424,20 +1427,9 @@ class KernelDoc:
             cont = doc_content.group(1)
 
             if cont == "":
-                if self.entry.section == self.section_context:
-                    self.entry.begin_section(ln, dump = True)
-                    self.state = state.BODY
-                else:
-                    if self.entry.section != SECTION_DEFAULT:
-                        self.state = state.SPECIAL_SECTION
-                    else:
-                        self.state = state.BODY
-
                     self.entry.contents += "\n"
-
             else:
-                if self.entry.section.startswith('@') or        \
-                   self.entry.section == self.section_context:
+                if self.state == state.SPECIAL_SECTION:
                     if self.entry.leading_space is None:
                         r = KernRe(r'^(\s+)')
                         if r.match(cont):