Rather than fill our text files with :c:func:`function()` syntax, just do
the markup via a hook into the sphinx build process. As is always the
case, the real problem is detecting the situations where this markup should
*not* be done.
Signed-off-by: Jonathan Corbet <corbet@xxxxxxx>
---
Documentation/conf.py | 3 +-
Documentation/sphinx/automarkup.py | 90 ++++++++++++++++++++++++++++++
2 files changed, 92 insertions(+), 1 deletion(-)
create mode 100644 Documentation/sphinx/automarkup.py
diff --git a/Documentation/conf.py b/Documentation/conf.py
index 72647a38b5c2..ba7b2846b1c5 100644
--- a/Documentation/conf.py
+++ b/Documentation/conf.py
@@ -34,7 +34,8 @@ needs_sphinx = '1.3'
# Add any Sphinx extension module names here, as strings. They can be
# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
# ones.
-extensions = ['kerneldoc', 'rstFlatTable', 'kernel_include', 'cdomain', 'kfigure', 'sphinx.ext.ifconfig']
+extensions = ['kerneldoc', 'rstFlatTable', 'kernel_include', 'cdomain',
+ 'kfigure', 'sphinx.ext.ifconfig', 'automarkup']
# The name of the math extension changed on Sphinx 1.4
if major == 1 and minor > 3:
diff --git a/Documentation/sphinx/automarkup.py b/Documentation/sphinx/automarkup.py
new file mode 100644
index 000000000000..c47469372bae
--- /dev/null
+++ b/Documentation/sphinx/automarkup.py
@@ -0,0 +1,90 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# This is a little Sphinx extension that tries to apply certain kinds
+# of markup automatically so we can keep it out of the text files
+# themselves.
+#
+# It's possible that this could be done better by hooking into the build
+# much later and traversing through the doctree. That would eliminate the
+# need to duplicate some RST parsing and perhaps be less fragile, at the
+# cost of some more complexity and the need to generate the cross-reference
+# links ourselves.
+#
+# Copyright 2019 Jonathan Corbet <corbet@xxxxxxx>
+#
+from __future__ import print_function
+import re
+import sphinx
+
+#
+# Regex nastiness. Of course.
+# Try to identify "function()" that's not already marked up some
+# other way. Sphinx doesn't like a lot of stuff right after a
+# :c:func: block (i.e. ":c:func:`mmap()`s" flakes out), so the last
+# bit tries to restrict matches to things that won't create trouble.
+#
+RE_function = re.compile(r'(^|\s+)([\w\d_]+\(\))([.,/\s]|$)')
+#
+# Lines consisting of a single underline character.
+#
+RE_underline = re.compile(r'^([-=~])\1+$')
+#
+# Starting a literal block.
+#
+RE_literal = re.compile(r'^(\s*)(.*::\s*|\.\.\s+code-block::.*)$')
+#
+# Just get the white space beginning a line.
+#
+RE_whitesp = re.compile(r'^(\s*)')
+
+def MangleFile(app, docname, text):
+ ret = [ ]
+ previous = ''
+ literal = False
+ for line in text[0].split('\n'):
+ #
+ # See if we might be ending a literal block, as denoted by
+ # an indent no greater than when we started.
+ #
+ if literal and len(line) > 0:
+ m = RE_whitesp.match(line) # Should always match
+ if len(m.group(1).expandtabs()) <= lit_indent:
+ literal = False
+ #
+ # Blank lines, directives, and lines within literal blocks
+ # should not be messed with.
+ #
+ if literal or len(line) == 0 or line[0] == '.':
+ ret.append(line)
+ #
+ # Is this an underline line? If so, and it is the same length
+ # as the previous line, we may have mangled a heading line in
+ # error, so undo it.
+ #
+ elif RE_underline.match(line):
+ if len(line) == len(previous):
+ ret[-1] = previous
+ ret.append(line)
+ #
+ # Normal line - perform substitutions.
+ #
+ else:
+ ret.append(RE_function.sub(r'\1:c:func:`\2`\3', line))
+ #
+ # Might we be starting a literal block? If so make note of
+ # the fact.
+ #
+ m = RE_literal.match(line)
+ if m:
+ literal = True
+ lit_indent = len(m.group(1).expandtabs())
+ previous = line
+ text[0] = '\n'.join(ret)
+
+def setup(app):
+ app.connect('source-read', MangleFile)
+
+ return dict(
+ parallel_read_safe = True,
+ parallel_write_safe = True
+ )
--
2.21.0
