291 lines
9.9 KiB
Python
291 lines
9.9 KiB
Python
# SPDX-License-Identifier: GPL-2.0
|
|
# Copyright 2019 Jonathan Corbet <corbet@lwn.net>
|
|
#
|
|
# 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
|
|
else:
|
|
from sphinx.errors import NoUri
|
|
import re
|
|
from itertools import chain
|
|
|
|
#
|
|
# Python 2 lacks re.ASCII...
|
|
#
|
|
try:
|
|
ascii_p3 = re.ASCII
|
|
except AttributeError:
|
|
ascii_p3 = 0
|
|
|
|
#
|
|
# 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'\b(([a-zA-Z_]\w+)\(\))', flags=ascii_p3)
|
|
|
|
#
|
|
# Sphinx 2 uses the same :c:type role for struct, union, enum and typedef
|
|
#
|
|
RE_generic_type = re.compile(r'\b(struct|union|enum|typedef)\s+([a-zA-Z_]\w+)',
|
|
flags=ascii_p3)
|
|
|
|
#
|
|
# Sphinx 3 uses a different C role for each one of struct, union, enum and
|
|
# typedef
|
|
#
|
|
RE_struct = re.compile(r'\b(struct)\s+([a-zA-Z_]\w+)', flags=ascii_p3)
|
|
RE_union = re.compile(r'\b(union)\s+([a-zA-Z_]\w+)', flags=ascii_p3)
|
|
RE_enum = re.compile(r'\b(enum)\s+([a-zA-Z_]\w+)', flags=ascii_p3)
|
|
RE_typedef = re.compile(r'\b(typedef)\s+([a-zA-Z_]\w+)', flags=ascii_p3)
|
|
|
|
#
|
|
# Detects a reference to a documentation page of the form Documentation/... with
|
|
# an optional extension
|
|
#
|
|
RE_doc = re.compile(r'\bDocumentation(/[\w\-_/]+)(\.\w+)*')
|
|
|
|
RE_namespace = re.compile(r'^\s*..\s*c:namespace::\s*(\S+)\s*$')
|
|
|
|
#
|
|
# Reserved C words that we should skip when cross-referencing
|
|
#
|
|
Skipnames = [ 'for', 'if', 'register', 'sizeof', 'struct', 'unsigned' ]
|
|
|
|
|
|
#
|
|
# 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' ]
|
|
|
|
c_namespace = ''
|
|
|
|
def markup_refs(docname, app, node):
|
|
t = node.astext()
|
|
done = 0
|
|
repl = [ ]
|
|
#
|
|
# Associate each regex with the function that will markup its matches
|
|
#
|
|
markup_func_sphinx2 = {RE_doc: markup_doc_ref,
|
|
RE_function: markup_c_ref,
|
|
RE_generic_type: markup_c_ref}
|
|
|
|
markup_func_sphinx3 = {RE_doc: markup_doc_ref,
|
|
RE_function: markup_func_ref_sphinx3,
|
|
RE_struct: markup_c_ref,
|
|
RE_union: markup_c_ref,
|
|
RE_enum: markup_c_ref,
|
|
RE_typedef: markup_c_ref}
|
|
|
|
if sphinx.version_info[0] >= 3:
|
|
markup_func = markup_func_sphinx3
|
|
else:
|
|
markup_func = markup_func_sphinx2
|
|
|
|
match_iterators = [regex.finditer(t) for regex in markup_func]
|
|
#
|
|
# Sort all references by the starting position in text
|
|
#
|
|
sorted_matches = sorted(chain(*match_iterators), key=lambda m: m.start())
|
|
for m in sorted_matches:
|
|
#
|
|
# Include any text prior to match as a normal text node.
|
|
#
|
|
if m.start() > done:
|
|
repl.append(nodes.Text(t[done:m.start()]))
|
|
|
|
#
|
|
# Call the function associated with the regex that matched this text and
|
|
# append its return to the text
|
|
#
|
|
repl.append(markup_func[m.re](docname, app, m))
|
|
|
|
done = m.end()
|
|
if done < len(t):
|
|
repl.append(nodes.Text(t[done:]))
|
|
return repl
|
|
|
|
#
|
|
# In sphinx3 we can cross-reference to C macro and function, each one with its
|
|
# own C role, but both match the same regex, so we try both.
|
|
#
|
|
def markup_func_ref_sphinx3(docname, app, match):
|
|
class_str = ['c-func', 'c-macro']
|
|
reftype_str = ['function', 'macro']
|
|
|
|
cdom = app.env.domains['c']
|
|
#
|
|
# Go through the dance of getting an xref out of the C domain
|
|
#
|
|
base_target = match.group(2)
|
|
target_text = nodes.Text(match.group(0))
|
|
xref = None
|
|
possible_targets = [base_target]
|
|
# Check if this document has a namespace, and if so, try
|
|
# cross-referencing inside it first.
|
|
if c_namespace:
|
|
possible_targets.insert(0, c_namespace + "." + base_target)
|
|
|
|
if base_target not in Skipnames:
|
|
for target in possible_targets:
|
|
if target not in Skipfuncs:
|
|
for class_s, reftype_s in zip(class_str, reftype_str):
|
|
lit_text = nodes.literal(classes=['xref', 'c', class_s])
|
|
lit_text += target_text
|
|
pxref = addnodes.pending_xref('', refdomain = 'c',
|
|
reftype = reftype_s,
|
|
reftarget = target, modname = None,
|
|
classname = None)
|
|
#
|
|
# XXX The Latex builder will throw NoUri exceptions here,
|
|
# work around that by ignoring them.
|
|
#
|
|
try:
|
|
xref = cdom.resolve_xref(app.env, docname, app.builder,
|
|
reftype_s, target, pxref,
|
|
lit_text)
|
|
except NoUri:
|
|
xref = None
|
|
|
|
if xref:
|
|
return xref
|
|
|
|
return target_text
|
|
|
|
def markup_c_ref(docname, app, match):
|
|
class_str = {# Sphinx 2 only
|
|
RE_function: 'c-func',
|
|
RE_generic_type: 'c-type',
|
|
# Sphinx 3+ only
|
|
RE_struct: 'c-struct',
|
|
RE_union: 'c-union',
|
|
RE_enum: 'c-enum',
|
|
RE_typedef: 'c-type',
|
|
}
|
|
reftype_str = {# Sphinx 2 only
|
|
RE_function: 'function',
|
|
RE_generic_type: 'type',
|
|
# Sphinx 3+ only
|
|
RE_struct: 'struct',
|
|
RE_union: 'union',
|
|
RE_enum: 'enum',
|
|
RE_typedef: 'type',
|
|
}
|
|
|
|
cdom = app.env.domains['c']
|
|
#
|
|
# Go through the dance of getting an xref out of the C domain
|
|
#
|
|
base_target = match.group(2)
|
|
target_text = nodes.Text(match.group(0))
|
|
xref = None
|
|
possible_targets = [base_target]
|
|
# Check if this document has a namespace, and if so, try
|
|
# cross-referencing inside it first.
|
|
if c_namespace:
|
|
possible_targets.insert(0, c_namespace + "." + base_target)
|
|
|
|
if base_target not in Skipnames:
|
|
for target in possible_targets:
|
|
if not (match.re == RE_function and target in Skipfuncs):
|
|
lit_text = nodes.literal(classes=['xref', 'c', class_str[match.re]])
|
|
lit_text += target_text
|
|
pxref = addnodes.pending_xref('', refdomain = 'c',
|
|
reftype = reftype_str[match.re],
|
|
reftarget = target, modname = None,
|
|
classname = None)
|
|
#
|
|
# XXX The Latex builder will throw NoUri exceptions here,
|
|
# work around that by ignoring them.
|
|
#
|
|
try:
|
|
xref = cdom.resolve_xref(app.env, docname, app.builder,
|
|
reftype_str[match.re], target, pxref,
|
|
lit_text)
|
|
except NoUri:
|
|
xref = None
|
|
|
|
if xref:
|
|
return xref
|
|
|
|
return target_text
|
|
|
|
#
|
|
# Try to replace a documentation reference of the form Documentation/... with a
|
|
# cross reference to that page
|
|
#
|
|
def markup_doc_ref(docname, app, match):
|
|
stddom = app.env.domains['std']
|
|
#
|
|
# Go through the dance of getting an xref out of the std domain
|
|
#
|
|
target = match.group(1)
|
|
xref = None
|
|
pxref = addnodes.pending_xref('', refdomain = 'std', reftype = 'doc',
|
|
reftarget = target, modname = None,
|
|
classname = None, refexplicit = False)
|
|
#
|
|
# XXX The Latex builder will throw NoUri exceptions here,
|
|
# work around that by ignoring them.
|
|
#
|
|
try:
|
|
xref = stddom.resolve_xref(app.env, docname, app.builder, 'doc',
|
|
target, pxref, None)
|
|
except NoUri:
|
|
xref = None
|
|
#
|
|
# Return the xref if we got it; otherwise just return the plain text.
|
|
#
|
|
if xref:
|
|
return xref
|
|
else:
|
|
return nodes.Text(match.group(0))
|
|
|
|
def get_c_namespace(app, docname):
|
|
source = app.env.doc2path(docname)
|
|
with open(source) as f:
|
|
for l in f:
|
|
match = RE_namespace.search(l)
|
|
if match:
|
|
return match.group(1)
|
|
return ''
|
|
|
|
def auto_markup(app, doctree, name):
|
|
global c_namespace
|
|
c_namespace = get_c_namespace(app, 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_refs(name, app, node))
|
|
|
|
def setup(app):
|
|
app.connect('doctree-resolved', auto_markup)
|
|
return {
|
|
'parallel_read_safe': True,
|
|
'parallel_write_safe': True,
|
|
}
|