blob: b1823637074224c1141b20267915fe703ea36687 [file] [log] [blame]
# SPDX-License-Identifier: GPL-2.0
# Copyright 2019 Jonathan Corbet <>
# Apply kernel-specific tweaks after the initial document processing
# has been done.
from docutils import nodes
import sphinx
from sphinx import addnodes
if sphinx.version_info[0] < 2 or \
sphinx.version_info[0] == 2 and sphinx.version_info[1] < 1:
from sphinx.environment import NoUri
from sphinx.errors import NoUri
import re
# 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'([\w_][\w\d_]+\(\))')
# Many places in the docs refer to common system calls. It is
# pointless to try to cross-reference them and, as has been known
# to happen, somebody defining a function by these names can lead
# to the creation of incorrect and confusing cross references. So
# just don't even try with these names.
Skipfuncs = [ 'open', 'close', 'read', 'write', 'fcntl', 'mmap',
'select', 'poll', 'fork', 'execve', 'clone', 'ioctl',
'socket' ]
# Find all occurrences of function() and try to replace them with
# appropriate cross references.
def markup_funcs(docname, app, node):
cdom =['c']
t = node.astext()
done = 0
repl = [ ]
for m in RE_function.finditer(t):
# Include any text prior to function() as a normal text node.
if m.start() > done:
# Go through the dance of getting an xref out of the C domain
target =[:-2]
target_text = nodes.Text(target + '()')
xref = None
if target not in Skipfuncs:
lit_text = nodes.literal(classes=['xref', 'c', 'c-func'])
lit_text += target_text
pxref = addnodes.pending_xref('', refdomain = 'c',
reftype = 'function',
reftarget = target, modname = None,
classname = None)
# XXX The Latex builder will throw NoUri exceptions here,
# work around that by ignoring them.
xref = cdom.resolve_xref(app.env, docname, app.builder,
'function', target, pxref, lit_text)
except NoUri:
xref = None
# Toss the xref into the list if we got it; otherwise just put
# the function text.
if xref:
done = m.end()
if done < len(t):
return repl
def auto_markup(app, doctree, name):
# This loop could eventually be improved on. Someday maybe we
# want a proper tree traversal with a lot of awareness of which
# kinds of nodes to prune. But this works well for now.
# The nodes.literal test catches ``literal text``, its purpose is to
# avoid adding cross-references to functions that have been explicitly
# marked with cc:func:.
for para in doctree.traverse(nodes.paragraph):
for node in para.traverse(nodes.Text):
if not isinstance(node.parent, nodes.literal):
node.parent.replace(node, markup_funcs(name, app, node))
def setup(app):
app.connect('doctree-resolved', auto_markup)
return {
'parallel_read_safe': True,
'parallel_write_safe': True,