Documentation/sphinx/cdomain.py

   1 # -*- coding: utf-8; mode: python -*-
   2 # pylint: disable=W0141,C0113,C0103,C0325
   3 u"""
   4     cdomain
   5     ~~~~~~~
   6
   7     Replacement for the sphinx c-domain.
   8
   9     :copyright:  Copyright (C) 2016  Markus Heiser
  10     :license:    GPL Version 2, June 1991 see Linux/COPYING for details.
  11
  12     List of customizations:
  13
  14     * Moved the *duplicate C object description* warnings for function
  15       declarations in the nitpicky mode. See Sphinx documentation for
  16       the config values for ``nitpick`` and ``nitpick_ignore``.
  17
  18     * Add option 'name' to the "c:function:" directive.  With option 'name' the
  19       ref-name of a function can be modified. E.g.::
  20
  21           .. c:function:: int ioctl( int fd, int request )
  22              :name: VIDIOC_LOG_STATUS
  23
  24       The func-name (e.g. ioctl) remains in the output but the ref-name changed
  25       from 'ioctl' to 'VIDIOC_LOG_STATUS'. The function is referenced by::
  26
  27           * :c:func:`VIDIOC_LOG_STATUS` or
  28           * :any:`VIDIOC_LOG_STATUS` (``:any:`` needs sphinx 1.3)
  29
  30      * Handle signatures of function-like macros well. Don't try to deduce
  31        arguments types of function-like macros.
  32
  33 """
  34
  35 from docutils import nodes
  36 from docutils.parsers.rst import directives
  37
  38 import sphinx
  39 from sphinx import addnodes
  40 from sphinx.domains.c import c_funcptr_sig_re, c_sig_re
  41 from sphinx.domains.c import CObject as Base_CObject
  42 from sphinx.domains.c import CDomain as Base_CDomain
  43 from itertools import chain
  44 import re
  45
  46 __version__  = '1.1'
  47
  48 # Get Sphinx version
  49 major, minor, patch = sphinx.version_info[:3]
  50
  51 # Namespace to be prepended to the full name
  52 namespace = None
  53
  54 #
  55 # Handle trivial newer c domain tags that are part of Sphinx 3.1 c domain tags
  56 # - Store the namespace if ".. c:namespace::" tag is found
  57 #
  58 RE_namespace = re.compile(r'^\s*..\s*c:namespace::\s*(\S+)\s*$')
  59
  60 def markup_namespace(match):
  61     global namespace
  62
  63     namespace = match.group(1)
  64
  65     return ""
  66
  67 #
  68 # Handle c:macro for function-style declaration
  69 #
  70 RE_macro = re.compile(r'^\s*..\s*c:macro::\s*(\S+)\s+(\S.*)\s*$')
  71 def markup_macro(match):
  72     return ".. c:function:: " + match.group(1) + ' ' + match.group(2)
  73
  74 #
  75 # Handle newer c domain tags that are evaluated as .. c:type: for
  76 # backward-compatibility with Sphinx < 3.0
  77 #
  78 RE_ctype = re.compile(r'^\s*..\s*c:(struct|union|enum|enumerator|alias)::\s*(.*)$')
  79
  80 def markup_ctype(match):
  81     return ".. c:type:: " + match.group(2)
  82
  83 #
  84 # Handle newer c domain tags that are evaluated as :c:type: for
  85 # backward-compatibility with Sphinx < 3.0
  86 #
  87 RE_ctype_refs = re.compile(r':c:(var|struct|union|enum|enumerator)::`([^\`]+)`')
  88 def markup_ctype_refs(match):
  89     return ":c:type:`" + match.group(2) + '`'
  90
  91 #
  92 # Simply convert :c:expr: and :c:texpr: into a literal block.
  93 #
  94 RE_expr = re.compile(r':c:(expr|texpr):`([^\`]+)`')
  95 def markup_c_expr(match):
  96     return '\ ``' + match.group(2) + '``\ '
  97
  98 #
  99 # Parse Sphinx 3.x C markups, replacing them by backward-compatible ones
 100 #
 101 def c_markups(app, docname, source):
 102     result = ""
 103     markup_func = {
 104         RE_namespace: markup_namespace,
 105         RE_expr: markup_c_expr,
 106         RE_macro: markup_macro,
 107         RE_ctype: markup_ctype,
 108         RE_ctype_refs: markup_ctype_refs,
 109     }
 110
 111     lines = iter(source[0].splitlines(True))
 112     for n in lines:
 113         match_iterators = [regex.finditer(n) for regex in markup_func]
 114         matches = sorted(chain(*match_iterators), key=lambda m: m.start())
 115         for m in matches:
 116             n = n[:m.start()] + markup_func[m.re](m) + n[m.end():]
 117
 118         result = result + n
 119
 120     source[0] = result
 121
 122 #
 123 # Now implements support for the cdomain namespacing logic
 124 #
 125
 126 def setup(app):
 127
 128     # Handle easy Sphinx 3.1+ simple new tags: :c:expr and .. c:namespace::
 129     app.connect('source-read', c_markups)
 130
 131     if (major == 1 and minor < 8):
 132         app.override_domain(CDomain)
 133     else:
 134         app.add_domain(CDomain, override=True)
 135
 136     return dict(
 137         version = __version__,
 138         parallel_read_safe = True,
 139         parallel_write_safe = True
 140     )
 141
 142 class CObject(Base_CObject):
 143
 144     """
 145     Description of a C language object.
 146     """
 147     option_spec = {
 148         "name" : directives.unchanged
 149     }
 150
 151     def handle_func_like_macro(self, sig, signode):
 152         u"""Handles signatures of function-like macros.
 153
 154         If the objtype is 'function' and the the signature ``sig`` is a
 155         function-like macro, the name of the macro is returned. Otherwise
 156         ``False`` is returned.  """
 157
 158         global namespace
 159
 160         if not self.objtype == 'function':
 161             return False
 162
 163         m = c_funcptr_sig_re.match(sig)
 164         if m is None:
 165             m = c_sig_re.match(sig)
 166             if m is None:
 167                 raise ValueError('no match')
 168
 169         rettype, fullname, arglist, _const = m.groups()
 170         arglist = arglist.strip()
 171         if rettype or not arglist:
 172             return False
 173
 174         arglist = arglist.replace('`', '').replace('\\ ', '') # remove markup
 175         arglist = [a.strip() for a in arglist.split(",")]
 176
 177         # has the first argument a type?
 178         if len(arglist[0].split(" ")) > 1:
 179             return False
 180
 181         # This is a function-like macro, it's arguments are typeless!
 182         signode  += addnodes.desc_name(fullname, fullname)
 183         paramlist = addnodes.desc_parameterlist()
 184         signode  += paramlist
 185
 186         for argname in arglist:
 187             param = addnodes.desc_parameter('', '', noemph=True)
 188             # separate by non-breaking space in the output
 189             param += nodes.emphasis(argname, argname)
 190             paramlist += param
 191
 192         if namespace:
 193             fullname = namespace + "." + fullname
 194
 195         return fullname
 196
 197     def handle_signature(self, sig, signode):
 198         """Transform a C signature into RST nodes."""
 199
 200         global namespace
 201
 202         fullname = self.handle_func_like_macro(sig, signode)
 203         if not fullname:
 204             fullname = super(CObject, self).handle_signature(sig, signode)
 205
 206         if "name" in self.options:
 207             if self.objtype == 'function':
 208                 fullname = self.options["name"]
 209             else:
 210                 # FIXME: handle :name: value of other declaration types?
 211                 pass
 212         else:
 213             if namespace:
 214                 fullname = namespace + "." + fullname
 215
 216         return fullname
 217
 218     def add_target_and_index(self, name, sig, signode):
 219         # for C API items we add a prefix since names are usually not qualified
 220         # by a module name and so easily clash with e.g. section titles
 221         targetname = 'c.' + name
 222         if targetname not in self.state.document.ids:
 223             signode['names'].append(targetname)
 224             signode['ids'].append(targetname)
 225             signode['first'] = (not self.names)
 226             self.state.document.note_explicit_target(signode)
 227             inv = self.env.domaindata['c']['objects']
 228             if (name in inv and self.env.config.nitpicky):
 229                 if self.objtype == 'function':
 230                     if ('c:func', name) not in self.env.config.nitpick_ignore:
 231                         self.state_machine.reporter.warning(
 232                             'duplicate C object description of %s, ' % name +
 233                             'other instance in ' + self.env.doc2path(inv[name][0]),
 234                             line=self.lineno)
 235             inv[name] = (self.env.docname, self.objtype)
 236
 237         indextext = self.get_index_text(name)
 238         if indextext:
 239             self.indexnode['entries'].append(
 240                     ('single', indextext, targetname, '', None))
 241
 242 class CDomain(Base_CDomain):
 243
 244     """C language domain."""
 245     name = 'c'
 246     label = 'C'
 247     directives = {
 248         'function': CObject,
 249         'member':   CObject,
 250         'macro':    CObject,
 251         'type':     CObject,
 252         'var':      CObject,
 253     }