xref: /openbmc/qemu/scripts/qapi/common.py (revision ccadd6bcba3bef6c1954f533b10224fb3db7148e)
1#
2# QAPI helper library
3#
4# Copyright IBM, Corp. 2011
5# Copyright (c) 2013-2018 Red Hat Inc.
6#
7# Authors:
8#  Anthony Liguori <aliguori@us.ibm.com>
9#  Markus Armbruster <armbru@redhat.com>
10#
11# This work is licensed under the terms of the GNU GPL, version 2.
12# See the COPYING file in the top-level directory.
13
14from __future__ import print_function
15from contextlib import contextmanager
16import errno
17import os
18import re
19import string
20import sys
21from collections import OrderedDict
22
23builtin_types = {
24    'null':     'QTYPE_QNULL',
25    'str':      'QTYPE_QSTRING',
26    'int':      'QTYPE_QNUM',
27    'number':   'QTYPE_QNUM',
28    'bool':     'QTYPE_QBOOL',
29    'int8':     'QTYPE_QNUM',
30    'int16':    'QTYPE_QNUM',
31    'int32':    'QTYPE_QNUM',
32    'int64':    'QTYPE_QNUM',
33    'uint8':    'QTYPE_QNUM',
34    'uint16':   'QTYPE_QNUM',
35    'uint32':   'QTYPE_QNUM',
36    'uint64':   'QTYPE_QNUM',
37    'size':     'QTYPE_QNUM',
38    'any':      None,           # any QType possible, actually
39    'QType':    'QTYPE_QSTRING',
40}
41
42# Are documentation comments required?
43doc_required = False
44
45# Whitelist of commands allowed to return a non-dictionary
46returns_whitelist = []
47
48# Whitelist of entities allowed to violate case conventions
49name_case_whitelist = []
50
51enum_types = {}
52struct_types = {}
53union_types = {}
54all_names = {}
55
56#
57# Parsing the schema into expressions
58#
59
60
61def error_path(parent):
62    res = ''
63    while parent:
64        res = ('In file included from %s:%d:\n' % (parent['file'],
65                                                   parent['line'])) + res
66        parent = parent['parent']
67    return res
68
69
70class QAPIError(Exception):
71    def __init__(self, fname, line, col, incl_info, msg):
72        Exception.__init__(self)
73        self.fname = fname
74        self.line = line
75        self.col = col
76        self.info = incl_info
77        self.msg = msg
78
79    def __str__(self):
80        loc = '%s:%d' % (self.fname, self.line)
81        if self.col is not None:
82            loc += ':%s' % self.col
83        return error_path(self.info) + '%s: %s' % (loc, self.msg)
84
85
86class QAPIParseError(QAPIError):
87    def __init__(self, parser, msg):
88        col = 1
89        for ch in parser.src[parser.line_pos:parser.pos]:
90            if ch == '\t':
91                col = (col + 7) % 8 + 1
92            else:
93                col += 1
94        QAPIError.__init__(self, parser.fname, parser.line, col,
95                           parser.incl_info, msg)
96
97
98class QAPISemError(QAPIError):
99    def __init__(self, info, msg):
100        QAPIError.__init__(self, info['file'], info['line'], None,
101                           info['parent'], msg)
102
103
104class QAPIDoc(object):
105    class Section(object):
106        def __init__(self, name=None):
107            # optional section name (argument/member or section name)
108            self.name = name
109            # the list of lines for this section
110            self.text = ''
111
112        def append(self, line):
113            self.text += line.rstrip() + '\n'
114
115    class ArgSection(Section):
116        def __init__(self, name):
117            QAPIDoc.Section.__init__(self, name)
118            self.member = None
119
120        def connect(self, member):
121            self.member = member
122
123    def __init__(self, parser, info):
124        # self._parser is used to report errors with QAPIParseError.  The
125        # resulting error position depends on the state of the parser.
126        # It happens to be the beginning of the comment.  More or less
127        # servicable, but action at a distance.
128        self._parser = parser
129        self.info = info
130        self.symbol = None
131        self.body = QAPIDoc.Section()
132        # dict mapping parameter name to ArgSection
133        self.args = OrderedDict()
134        # a list of Section
135        self.sections = []
136        # the current section
137        self._section = self.body
138
139    def has_section(self, name):
140        """Return True if we have a section with this name."""
141        for i in self.sections:
142            if i.name == name:
143                return True
144        return False
145
146    def append(self, line):
147        """Parse a comment line and add it to the documentation."""
148        line = line[1:]
149        if not line:
150            self._append_freeform(line)
151            return
152
153        if line[0] != ' ':
154            raise QAPIParseError(self._parser, "Missing space after #")
155        line = line[1:]
156
157        # FIXME not nice: things like '#  @foo:' and '# @foo: ' aren't
158        # recognized, and get silently treated as ordinary text
159        if self.symbol:
160            self._append_symbol_line(line)
161        elif not self.body.text and line.startswith('@'):
162            if not line.endswith(':'):
163                raise QAPIParseError(self._parser, "Line should end with :")
164            self.symbol = line[1:-1]
165            # FIXME invalid names other than the empty string aren't flagged
166            if not self.symbol:
167                raise QAPIParseError(self._parser, "Invalid name")
168        else:
169            self._append_freeform(line)
170
171    def end_comment(self):
172        self._end_section()
173
174    def _append_symbol_line(self, line):
175        name = line.split(' ', 1)[0]
176
177        if name.startswith('@') and name.endswith(':'):
178            line = line[len(name)+1:]
179            self._start_args_section(name[1:-1])
180        elif name in ('Returns:', 'Since:',
181                      # those are often singular or plural
182                      'Note:', 'Notes:',
183                      'Example:', 'Examples:',
184                      'TODO:'):
185            line = line[len(name)+1:]
186            self._start_section(name[:-1])
187
188        self._append_freeform(line)
189
190    def _start_args_section(self, name):
191        # FIXME invalid names other than the empty string aren't flagged
192        if not name:
193            raise QAPIParseError(self._parser, "Invalid parameter name")
194        if name in self.args:
195            raise QAPIParseError(self._parser,
196                                 "'%s' parameter name duplicated" % name)
197        if self.sections:
198            raise QAPIParseError(self._parser,
199                                 "'@%s:' can't follow '%s' section"
200                                 % (name, self.sections[0].name))
201        self._end_section()
202        self._section = QAPIDoc.ArgSection(name)
203        self.args[name] = self._section
204
205    def _start_section(self, name=None):
206        if name in ('Returns', 'Since') and self.has_section(name):
207            raise QAPIParseError(self._parser,
208                                 "Duplicated '%s' section" % name)
209        self._end_section()
210        self._section = QAPIDoc.Section(name)
211        self.sections.append(self._section)
212
213    def _end_section(self):
214        if self._section:
215            text = self._section.text = self._section.text.strip()
216            if self._section.name and (not text or text.isspace()):
217                raise QAPIParseError(self._parser, "Empty doc section '%s'"
218                                     % self._section.name)
219            self._section = None
220
221    def _append_freeform(self, line):
222        in_arg = isinstance(self._section, QAPIDoc.ArgSection)
223        if (in_arg and self._section.text.endswith('\n\n')
224                and line and not line[0].isspace()):
225            self._start_section()
226        if (in_arg or not self._section.name
227                or not self._section.name.startswith('Example')):
228            line = line.strip()
229        match = re.match(r'(@\S+:)', line)
230        if match:
231            raise QAPIParseError(self._parser,
232                                 "'%s' not allowed in free-form documentation"
233                                 % match.group(1))
234        self._section.append(line)
235
236    def connect_member(self, member):
237        if member.name not in self.args:
238            # Undocumented TODO outlaw
239            self.args[member.name] = QAPIDoc.ArgSection(member.name)
240        self.args[member.name].connect(member)
241
242    def check_expr(self, expr):
243        if self.has_section('Returns') and 'command' not in expr:
244            raise QAPISemError(self.info,
245                               "'Returns:' is only valid for commands")
246
247    def check(self):
248        bogus = [name for name, section in self.args.items()
249                 if not section.member]
250        if bogus:
251            raise QAPISemError(
252                self.info,
253                "The following documented members are not in "
254                "the declaration: %s" % ", ".join(bogus))
255
256
257class QAPISchemaParser(object):
258
259    def __init__(self, fp, previously_included=[], incl_info=None):
260        self.fname = fp.name
261        previously_included.append(os.path.abspath(fp.name))
262        self.incl_info = incl_info
263        self.src = fp.read()
264        if self.src == '' or self.src[-1] != '\n':
265            self.src += '\n'
266        self.cursor = 0
267        self.line = 1
268        self.line_pos = 0
269        self.exprs = []
270        self.docs = []
271        self.accept()
272        cur_doc = None
273
274        while self.tok is not None:
275            info = {'file': self.fname, 'line': self.line,
276                    'parent': self.incl_info}
277            if self.tok == '#':
278                self.reject_expr_doc(cur_doc)
279                cur_doc = self.get_doc(info)
280                self.docs.append(cur_doc)
281                continue
282
283            expr = self.get_expr(False)
284            if 'include' in expr:
285                self.reject_expr_doc(cur_doc)
286                if len(expr) != 1:
287                    raise QAPISemError(info, "Invalid 'include' directive")
288                include = expr['include']
289                if not isinstance(include, str):
290                    raise QAPISemError(info,
291                                       "Value of 'include' must be a string")
292                incl_fname = os.path.join(os.path.dirname(self.fname),
293                                          include)
294                self.exprs.append({'expr': {'include': incl_fname},
295                                   'info': info})
296                exprs_include = self._include(include, info, incl_fname,
297                                              previously_included)
298                if exprs_include:
299                    self.exprs.extend(exprs_include.exprs)
300                    self.docs.extend(exprs_include.docs)
301            elif "pragma" in expr:
302                self.reject_expr_doc(cur_doc)
303                if len(expr) != 1:
304                    raise QAPISemError(info, "Invalid 'pragma' directive")
305                pragma = expr['pragma']
306                if not isinstance(pragma, dict):
307                    raise QAPISemError(
308                        info, "Value of 'pragma' must be a dictionary")
309                for name, value in pragma.items():
310                    self._pragma(name, value, info)
311            else:
312                expr_elem = {'expr': expr,
313                             'info': info}
314                if cur_doc:
315                    if not cur_doc.symbol:
316                        raise QAPISemError(
317                            cur_doc.info, "Expression documentation required")
318                    expr_elem['doc'] = cur_doc
319                self.exprs.append(expr_elem)
320            cur_doc = None
321        self.reject_expr_doc(cur_doc)
322
323    @staticmethod
324    def reject_expr_doc(doc):
325        if doc and doc.symbol:
326            raise QAPISemError(
327                doc.info,
328                "Documentation for '%s' is not followed by the definition"
329                % doc.symbol)
330
331    def _include(self, include, info, incl_fname, previously_included):
332        incl_abs_fname = os.path.abspath(incl_fname)
333        # catch inclusion cycle
334        inf = info
335        while inf:
336            if incl_abs_fname == os.path.abspath(inf['file']):
337                raise QAPISemError(info, "Inclusion loop for %s" % include)
338            inf = inf['parent']
339
340        # skip multiple include of the same file
341        if incl_abs_fname in previously_included:
342            return None
343
344        try:
345            if sys.version_info[0] >= 3:
346                fobj = open(incl_fname, 'r', encoding='utf-8')
347            else:
348                fobj = open(incl_fname, 'r')
349        except IOError as e:
350            raise QAPISemError(info, '%s: %s' % (e.strerror, incl_fname))
351        return QAPISchemaParser(fobj, previously_included, info)
352
353    def _pragma(self, name, value, info):
354        global doc_required, returns_whitelist, name_case_whitelist
355        if name == 'doc-required':
356            if not isinstance(value, bool):
357                raise QAPISemError(info,
358                                   "Pragma 'doc-required' must be boolean")
359            doc_required = value
360        elif name == 'returns-whitelist':
361            if (not isinstance(value, list)
362                    or any([not isinstance(elt, str) for elt in value])):
363                raise QAPISemError(info,
364                                   "Pragma returns-whitelist must be"
365                                   " a list of strings")
366            returns_whitelist = value
367        elif name == 'name-case-whitelist':
368            if (not isinstance(value, list)
369                    or any([not isinstance(elt, str) for elt in value])):
370                raise QAPISemError(info,
371                                   "Pragma name-case-whitelist must be"
372                                   " a list of strings")
373            name_case_whitelist = value
374        else:
375            raise QAPISemError(info, "Unknown pragma '%s'" % name)
376
377    def accept(self, skip_comment=True):
378        while True:
379            self.tok = self.src[self.cursor]
380            self.pos = self.cursor
381            self.cursor += 1
382            self.val = None
383
384            if self.tok == '#':
385                if self.src[self.cursor] == '#':
386                    # Start of doc comment
387                    skip_comment = False
388                self.cursor = self.src.find('\n', self.cursor)
389                if not skip_comment:
390                    self.val = self.src[self.pos:self.cursor]
391                    return
392            elif self.tok in '{}:,[]':
393                return
394            elif self.tok == "'":
395                string = ''
396                esc = False
397                while True:
398                    ch = self.src[self.cursor]
399                    self.cursor += 1
400                    if ch == '\n':
401                        raise QAPIParseError(self, 'Missing terminating "\'"')
402                    if esc:
403                        if ch == 'b':
404                            string += '\b'
405                        elif ch == 'f':
406                            string += '\f'
407                        elif ch == 'n':
408                            string += '\n'
409                        elif ch == 'r':
410                            string += '\r'
411                        elif ch == 't':
412                            string += '\t'
413                        elif ch == 'u':
414                            value = 0
415                            for _ in range(0, 4):
416                                ch = self.src[self.cursor]
417                                self.cursor += 1
418                                if ch not in '0123456789abcdefABCDEF':
419                                    raise QAPIParseError(self,
420                                                         '\\u escape needs 4 '
421                                                         'hex digits')
422                                value = (value << 4) + int(ch, 16)
423                            # If Python 2 and 3 didn't disagree so much on
424                            # how to handle Unicode, then we could allow
425                            # Unicode string defaults.  But most of QAPI is
426                            # ASCII-only, so we aren't losing much for now.
427                            if not value or value > 0x7f:
428                                raise QAPIParseError(self,
429                                                     'For now, \\u escape '
430                                                     'only supports non-zero '
431                                                     'values up to \\u007f')
432                            string += chr(value)
433                        elif ch in '\\/\'"':
434                            string += ch
435                        else:
436                            raise QAPIParseError(self,
437                                                 "Unknown escape \\%s" % ch)
438                        esc = False
439                    elif ch == '\\':
440                        esc = True
441                    elif ch == "'":
442                        self.val = string
443                        return
444                    else:
445                        string += ch
446            elif self.src.startswith('true', self.pos):
447                self.val = True
448                self.cursor += 3
449                return
450            elif self.src.startswith('false', self.pos):
451                self.val = False
452                self.cursor += 4
453                return
454            elif self.src.startswith('null', self.pos):
455                self.val = None
456                self.cursor += 3
457                return
458            elif self.tok == '\n':
459                if self.cursor == len(self.src):
460                    self.tok = None
461                    return
462                self.line += 1
463                self.line_pos = self.cursor
464            elif not self.tok.isspace():
465                raise QAPIParseError(self, 'Stray "%s"' % self.tok)
466
467    def get_members(self):
468        expr = OrderedDict()
469        if self.tok == '}':
470            self.accept()
471            return expr
472        if self.tok != "'":
473            raise QAPIParseError(self, 'Expected string or "}"')
474        while True:
475            key = self.val
476            self.accept()
477            if self.tok != ':':
478                raise QAPIParseError(self, 'Expected ":"')
479            self.accept()
480            if key in expr:
481                raise QAPIParseError(self, 'Duplicate key "%s"' % key)
482            expr[key] = self.get_expr(True)
483            if self.tok == '}':
484                self.accept()
485                return expr
486            if self.tok != ',':
487                raise QAPIParseError(self, 'Expected "," or "}"')
488            self.accept()
489            if self.tok != "'":
490                raise QAPIParseError(self, 'Expected string')
491
492    def get_values(self):
493        expr = []
494        if self.tok == ']':
495            self.accept()
496            return expr
497        if self.tok not in "{['tfn":
498            raise QAPIParseError(self, 'Expected "{", "[", "]", string, '
499                                 'boolean or "null"')
500        while True:
501            expr.append(self.get_expr(True))
502            if self.tok == ']':
503                self.accept()
504                return expr
505            if self.tok != ',':
506                raise QAPIParseError(self, 'Expected "," or "]"')
507            self.accept()
508
509    def get_expr(self, nested):
510        if self.tok != '{' and not nested:
511            raise QAPIParseError(self, 'Expected "{"')
512        if self.tok == '{':
513            self.accept()
514            expr = self.get_members()
515        elif self.tok == '[':
516            self.accept()
517            expr = self.get_values()
518        elif self.tok in "'tfn":
519            expr = self.val
520            self.accept()
521        else:
522            raise QAPIParseError(self, 'Expected "{", "[", string, '
523                                 'boolean or "null"')
524        return expr
525
526    def get_doc(self, info):
527        if self.val != '##':
528            raise QAPIParseError(self, "Junk after '##' at start of "
529                                 "documentation comment")
530
531        doc = QAPIDoc(self, info)
532        self.accept(False)
533        while self.tok == '#':
534            if self.val.startswith('##'):
535                # End of doc comment
536                if self.val != '##':
537                    raise QAPIParseError(self, "Junk after '##' at end of "
538                                         "documentation comment")
539                doc.end_comment()
540                self.accept()
541                return doc
542            else:
543                doc.append(self.val)
544            self.accept(False)
545
546        raise QAPIParseError(self, "Documentation comment must end with '##'")
547
548
549#
550# Semantic analysis of schema expressions
551# TODO fold into QAPISchema
552# TODO catching name collisions in generated code would be nice
553#
554
555
556def find_base_members(base):
557    if isinstance(base, dict):
558        return base
559    base_struct_define = struct_types.get(base)
560    if not base_struct_define:
561        return None
562    return base_struct_define['data']
563
564
565# Return the qtype of an alternate branch, or None on error.
566def find_alternate_member_qtype(qapi_type):
567    if qapi_type in builtin_types:
568        return builtin_types[qapi_type]
569    elif qapi_type in struct_types:
570        return 'QTYPE_QDICT'
571    elif qapi_type in enum_types:
572        return 'QTYPE_QSTRING'
573    elif qapi_type in union_types:
574        return 'QTYPE_QDICT'
575    return None
576
577
578# Return the discriminator enum define if discriminator is specified as an
579# enum type, otherwise return None.
580def discriminator_find_enum_define(expr):
581    base = expr.get('base')
582    discriminator = expr.get('discriminator')
583
584    if not (discriminator and base):
585        return None
586
587    base_members = find_base_members(base)
588    if not base_members:
589        return None
590
591    discriminator_value = base_members.get(discriminator)
592    if not discriminator_value:
593        return None
594
595    return enum_types.get(discriminator_value['type'])
596
597
598# Names must be letters, numbers, -, and _.  They must start with letter,
599# except for downstream extensions which must start with __RFQDN_.
600# Dots are only valid in the downstream extension prefix.
601valid_name = re.compile(r'^(__[a-zA-Z0-9.-]+_)?'
602                        '[a-zA-Z][a-zA-Z0-9_-]*$')
603
604
605def check_name(info, source, name, allow_optional=False,
606               enum_member=False):
607    global valid_name
608    membername = name
609
610    if not isinstance(name, str):
611        raise QAPISemError(info, "%s requires a string name" % source)
612    if name.startswith('*'):
613        membername = name[1:]
614        if not allow_optional:
615            raise QAPISemError(info, "%s does not allow optional name '%s'"
616                               % (source, name))
617    # Enum members can start with a digit, because the generated C
618    # code always prefixes it with the enum name
619    if enum_member and membername[0].isdigit():
620        membername = 'D' + membername
621    # Reserve the entire 'q_' namespace for c_name(), and for 'q_empty'
622    # and 'q_obj_*' implicit type names.
623    if not valid_name.match(membername) or \
624       c_name(membername, False).startswith('q_'):
625        raise QAPISemError(info, "%s uses invalid name '%s'" % (source, name))
626
627
628def add_name(name, info, meta, implicit=False):
629    global all_names
630    check_name(info, "'%s'" % meta, name)
631    # FIXME should reject names that differ only in '_' vs. '.'
632    # vs. '-', because they're liable to clash in generated C.
633    if name in all_names:
634        raise QAPISemError(info, "%s '%s' is already defined"
635                           % (all_names[name], name))
636    if not implicit and (name.endswith('Kind') or name.endswith('List')):
637        raise QAPISemError(info, "%s '%s' should not end in '%s'"
638                           % (meta, name, name[-4:]))
639    all_names[name] = meta
640
641
642def check_if(expr, info):
643
644    def check_if_str(ifcond, info):
645        if not isinstance(ifcond, str):
646            raise QAPISemError(
647                info, "'if' condition must be a string or a list of strings")
648        if ifcond == '':
649            raise QAPISemError(info, "'if' condition '' makes no sense")
650
651    ifcond = expr.get('if')
652    if ifcond is None:
653        return
654    if isinstance(ifcond, list):
655        if ifcond == []:
656            raise QAPISemError(info, "'if' condition [] is useless")
657        for elt in ifcond:
658            check_if_str(elt, info)
659    else:
660        check_if_str(ifcond, info)
661
662
663def check_type(info, source, value, allow_array=False,
664               allow_dict=False, allow_optional=False,
665               allow_metas=[]):
666    global all_names
667
668    if value is None:
669        return
670
671    # Check if array type for value is okay
672    if isinstance(value, list):
673        if not allow_array:
674            raise QAPISemError(info, "%s cannot be an array" % source)
675        if len(value) != 1 or not isinstance(value[0], str):
676            raise QAPISemError(info,
677                               "%s: array type must contain single type name" %
678                               source)
679        value = value[0]
680
681    # Check if type name for value is okay
682    if isinstance(value, str):
683        if value not in all_names:
684            raise QAPISemError(info, "%s uses unknown type '%s'"
685                               % (source, value))
686        if not all_names[value] in allow_metas:
687            raise QAPISemError(info, "%s cannot use %s type '%s'" %
688                               (source, all_names[value], value))
689        return
690
691    if not allow_dict:
692        raise QAPISemError(info, "%s should be a type name" % source)
693
694    if not isinstance(value, OrderedDict):
695        raise QAPISemError(info,
696                           "%s should be a dictionary or type name" % source)
697
698    # value is a dictionary, check that each member is okay
699    for (key, arg) in value.items():
700        check_name(info, "Member of %s" % source, key,
701                   allow_optional=allow_optional)
702        if c_name(key, False) == 'u' or c_name(key, False).startswith('has_'):
703            raise QAPISemError(info, "Member of %s uses reserved name '%s'"
704                               % (source, key))
705        # Todo: allow dictionaries to represent default values of
706        # an optional argument.
707        check_known_keys(info, "member '%s' of %s" % (key, source),
708                         arg, ['type'], ['if'])
709        check_type(info, "Member '%s' of %s" % (key, source),
710                   arg['type'], allow_array=True,
711                   allow_metas=['built-in', 'union', 'alternate', 'struct',
712                                'enum'])
713
714
715def check_command(expr, info):
716    name = expr['command']
717    boxed = expr.get('boxed', False)
718
719    args_meta = ['struct']
720    if boxed:
721        args_meta += ['union', 'alternate']
722    check_type(info, "'data' for command '%s'" % name,
723               expr.get('data'), allow_dict=not boxed, allow_optional=True,
724               allow_metas=args_meta)
725    returns_meta = ['union', 'struct']
726    if name in returns_whitelist:
727        returns_meta += ['built-in', 'alternate', 'enum']
728    check_type(info, "'returns' for command '%s'" % name,
729               expr.get('returns'), allow_array=True,
730               allow_optional=True, allow_metas=returns_meta)
731
732
733def check_event(expr, info):
734    name = expr['event']
735    boxed = expr.get('boxed', False)
736
737    meta = ['struct']
738    if boxed:
739        meta += ['union', 'alternate']
740    check_type(info, "'data' for event '%s'" % name,
741               expr.get('data'), allow_dict=not boxed, allow_optional=True,
742               allow_metas=meta)
743
744
745def enum_get_names(expr):
746    return [e['name'] for e in expr['data']]
747
748
749def check_union(expr, info):
750    name = expr['union']
751    base = expr.get('base')
752    discriminator = expr.get('discriminator')
753    members = expr['data']
754
755    # Two types of unions, determined by discriminator.
756
757    # With no discriminator it is a simple union.
758    if discriminator is None:
759        enum_define = None
760        allow_metas = ['built-in', 'union', 'alternate', 'struct', 'enum']
761        if base is not None:
762            raise QAPISemError(info, "Simple union '%s' must not have a base" %
763                               name)
764
765    # Else, it's a flat union.
766    else:
767        # The object must have a string or dictionary 'base'.
768        check_type(info, "'base' for union '%s'" % name,
769                   base, allow_dict=True, allow_optional=True,
770                   allow_metas=['struct'])
771        if not base:
772            raise QAPISemError(info, "Flat union '%s' must have a base"
773                               % name)
774        base_members = find_base_members(base)
775        assert base_members is not None
776
777        # The value of member 'discriminator' must name a non-optional
778        # member of the base struct.
779        check_name(info, "Discriminator of flat union '%s'" % name,
780                   discriminator)
781        discriminator_value = base_members.get(discriminator)
782        if not discriminator_value:
783            raise QAPISemError(info,
784                               "Discriminator '%s' is not a member of base "
785                               "struct '%s'"
786                               % (discriminator, base))
787        if discriminator_value.get('if'):
788            raise QAPISemError(info, 'The discriminator %s.%s for union %s '
789                               'must not be conditional' %
790                               (base, discriminator, name))
791        enum_define = enum_types.get(discriminator_value['type'])
792        allow_metas = ['struct']
793        # Do not allow string discriminator
794        if not enum_define:
795            raise QAPISemError(info,
796                               "Discriminator '%s' must be of enumeration "
797                               "type" % discriminator)
798
799    # Check every branch; don't allow an empty union
800    if len(members) == 0:
801        raise QAPISemError(info, "Union '%s' cannot have empty 'data'" % name)
802    for (key, value) in members.items():
803        check_name(info, "Member of union '%s'" % name, key)
804
805        check_known_keys(info, "member '%s' of union '%s'" % (key, name),
806                         value, ['type'], [])
807        # Each value must name a known type
808        check_type(info, "Member '%s' of union '%s'" % (key, name),
809                   value['type'],
810                   allow_array=not base, allow_metas=allow_metas)
811
812        # If the discriminator names an enum type, then all members
813        # of 'data' must also be members of the enum type.
814        if enum_define:
815            if key not in enum_get_names(enum_define):
816                raise QAPISemError(info,
817                                   "Discriminator value '%s' is not found in "
818                                   "enum '%s'"
819                                   % (key, enum_define['enum']))
820
821
822def check_alternate(expr, info):
823    name = expr['alternate']
824    members = expr['data']
825    types_seen = {}
826
827    # Check every branch; require at least two branches
828    if len(members) < 2:
829        raise QAPISemError(info,
830                           "Alternate '%s' should have at least two branches "
831                           "in 'data'" % name)
832    for (key, value) in members.items():
833        check_name(info, "Member of alternate '%s'" % name, key)
834        check_known_keys(info,
835                         "member '%s' of alternate '%s'" % (key, name),
836                         value, ['type'], [])
837        typ = value['type']
838
839        # Ensure alternates have no type conflicts.
840        check_type(info, "Member '%s' of alternate '%s'" % (key, name), typ,
841                   allow_metas=['built-in', 'union', 'struct', 'enum'])
842        qtype = find_alternate_member_qtype(typ)
843        if not qtype:
844            raise QAPISemError(info, "Alternate '%s' member '%s' cannot use "
845                               "type '%s'" % (name, key, typ))
846        conflicting = set([qtype])
847        if qtype == 'QTYPE_QSTRING':
848            enum_expr = enum_types.get(typ)
849            if enum_expr:
850                for v in enum_get_names(enum_expr):
851                    if v in ['on', 'off']:
852                        conflicting.add('QTYPE_QBOOL')
853                    if re.match(r'[-+0-9.]', v): # lazy, could be tightened
854                        conflicting.add('QTYPE_QNUM')
855            else:
856                conflicting.add('QTYPE_QNUM')
857                conflicting.add('QTYPE_QBOOL')
858        for qt in conflicting:
859            if qt in types_seen:
860                raise QAPISemError(info, "Alternate '%s' member '%s' can't "
861                                   "be distinguished from member '%s'"
862                                   % (name, key, types_seen[qt]))
863            types_seen[qt] = key
864
865
866def check_enum(expr, info):
867    name = expr['enum']
868    members = expr['data']
869    prefix = expr.get('prefix')
870
871    if not isinstance(members, list):
872        raise QAPISemError(info,
873                           "Enum '%s' requires an array for 'data'" % name)
874    if prefix is not None and not isinstance(prefix, str):
875        raise QAPISemError(info,
876                           "Enum '%s' requires a string for 'prefix'" % name)
877
878    for member in members:
879        source = "dictionary member of enum '%s'" % name
880        check_known_keys(info, source, member, ['name'], ['if'])
881        check_if(member, info)
882        check_name(info, "Member of enum '%s'" % name, member['name'],
883                   enum_member=True)
884
885
886def check_struct(expr, info):
887    name = expr['struct']
888    members = expr['data']
889
890    check_type(info, "'data' for struct '%s'" % name, members,
891               allow_dict=True, allow_optional=True)
892    check_type(info, "'base' for struct '%s'" % name, expr.get('base'),
893               allow_metas=['struct'])
894
895
896def check_known_keys(info, source, keys, required, optional):
897
898    def pprint(elems):
899        return ', '.join("'" + e + "'" for e in sorted(elems))
900
901    missing = set(required) - set(keys)
902    if missing:
903        raise QAPISemError(info, "Key%s %s %s missing from %s"
904                           % ('s' if len(missing) > 1 else '', pprint(missing),
905                              'are' if len(missing) > 1 else 'is', source))
906    allowed = set(required + optional)
907    unknown = set(keys) - allowed
908    if unknown:
909        raise QAPISemError(info, "Unknown key%s %s in %s\nValid keys are %s."
910                           % ('s' if len(unknown) > 1 else '', pprint(unknown),
911                              source, pprint(allowed)))
912
913
914def check_keys(expr_elem, meta, required, optional=[]):
915    expr = expr_elem['expr']
916    info = expr_elem['info']
917    name = expr[meta]
918    if not isinstance(name, str):
919        raise QAPISemError(info, "'%s' key must have a string value" % meta)
920    required = required + [meta]
921    source = "%s '%s'" % (meta, name)
922    check_known_keys(info, source, expr.keys(), required, optional)
923    for (key, value) in expr.items():
924        if key in ['gen', 'success-response'] and value is not False:
925            raise QAPISemError(info,
926                               "'%s' of %s '%s' should only use false value"
927                               % (key, meta, name))
928        if (key in ['boxed', 'allow-oob', 'allow-preconfig']
929                and value is not True):
930            raise QAPISemError(info,
931                               "'%s' of %s '%s' should only use true value"
932                               % (key, meta, name))
933        if key == 'if':
934            check_if(expr, info)
935
936
937def normalize_enum(expr):
938    if isinstance(expr['data'], list):
939        expr['data'] = [m if isinstance(m, dict) else {'name': m}
940                        for m in expr['data']]
941
942
943def normalize_members(members):
944    if isinstance(members, OrderedDict):
945        for key, arg in members.items():
946            if isinstance(arg, dict):
947                continue
948            members[key] = {'type': arg}
949
950
951def check_exprs(exprs):
952    global all_names
953
954    # Populate name table with names of built-in types
955    for builtin in builtin_types.keys():
956        all_names[builtin] = 'built-in'
957
958    # Learn the types and check for valid expression keys
959    for expr_elem in exprs:
960        expr = expr_elem['expr']
961        info = expr_elem['info']
962        doc = expr_elem.get('doc')
963
964        if 'include' in expr:
965            continue
966
967        if not doc and doc_required:
968            raise QAPISemError(info,
969                               "Expression missing documentation comment")
970
971        if 'enum' in expr:
972            meta = 'enum'
973            check_keys(expr_elem, 'enum', ['data'], ['if', 'prefix'])
974            normalize_enum(expr)
975            enum_types[expr[meta]] = expr
976        elif 'union' in expr:
977            meta = 'union'
978            check_keys(expr_elem, 'union', ['data'],
979                       ['base', 'discriminator', 'if'])
980            normalize_members(expr.get('base'))
981            normalize_members(expr['data'])
982            union_types[expr[meta]] = expr
983        elif 'alternate' in expr:
984            meta = 'alternate'
985            check_keys(expr_elem, 'alternate', ['data'], ['if'])
986            normalize_members(expr['data'])
987        elif 'struct' in expr:
988            meta = 'struct'
989            check_keys(expr_elem, 'struct', ['data'], ['base', 'if'])
990            normalize_members(expr['data'])
991            struct_types[expr[meta]] = expr
992        elif 'command' in expr:
993            meta = 'command'
994            check_keys(expr_elem, 'command', [],
995                       ['data', 'returns', 'gen', 'success-response',
996                        'boxed', 'allow-oob', 'allow-preconfig', 'if'])
997            normalize_members(expr.get('data'))
998        elif 'event' in expr:
999            meta = 'event'
1000            check_keys(expr_elem, 'event', [], ['data', 'boxed', 'if'])
1001            normalize_members(expr.get('data'))
1002        else:
1003            raise QAPISemError(expr_elem['info'],
1004                               "Expression is missing metatype")
1005        name = expr[meta]
1006        add_name(name, info, meta)
1007        if doc and doc.symbol != name:
1008            raise QAPISemError(info, "Definition of '%s' follows documentation"
1009                               " for '%s'" % (name, doc.symbol))
1010
1011    # Try again for hidden UnionKind enum
1012    for expr_elem in exprs:
1013        expr = expr_elem['expr']
1014
1015        if 'include' in expr:
1016            continue
1017        if 'union' in expr and not discriminator_find_enum_define(expr):
1018            name = '%sKind' % expr['union']
1019        elif 'alternate' in expr:
1020            name = '%sKind' % expr['alternate']
1021        else:
1022            continue
1023        enum_types[name] = {'enum': name}
1024        add_name(name, info, 'enum', implicit=True)
1025
1026    # Validate that exprs make sense
1027    for expr_elem in exprs:
1028        expr = expr_elem['expr']
1029        info = expr_elem['info']
1030        doc = expr_elem.get('doc')
1031
1032        if 'include' in expr:
1033            continue
1034        if 'enum' in expr:
1035            check_enum(expr, info)
1036        elif 'union' in expr:
1037            check_union(expr, info)
1038        elif 'alternate' in expr:
1039            check_alternate(expr, info)
1040        elif 'struct' in expr:
1041            check_struct(expr, info)
1042        elif 'command' in expr:
1043            check_command(expr, info)
1044        elif 'event' in expr:
1045            check_event(expr, info)
1046        else:
1047            assert False, 'unexpected meta type'
1048
1049        if doc:
1050            doc.check_expr(expr)
1051
1052    return exprs
1053
1054
1055#
1056# Schema compiler frontend
1057#
1058
1059def listify_cond(ifcond):
1060    if not ifcond:
1061        return []
1062    if not isinstance(ifcond, list):
1063        return [ifcond]
1064    return ifcond
1065
1066
1067class QAPISchemaEntity(object):
1068    def __init__(self, name, info, doc, ifcond=None):
1069        assert name is None or isinstance(name, str)
1070        self.name = name
1071        self.module = None
1072        # For explicitly defined entities, info points to the (explicit)
1073        # definition.  For builtins (and their arrays), info is None.
1074        # For implicitly defined entities, info points to a place that
1075        # triggered the implicit definition (there may be more than one
1076        # such place).
1077        self.info = info
1078        self.doc = doc
1079        self._ifcond = ifcond  # self.ifcond is set only after .check()
1080
1081    def c_name(self):
1082        return c_name(self.name)
1083
1084    def check(self, schema):
1085        if isinstance(self._ifcond, QAPISchemaType):
1086            # inherit the condition from a type
1087            typ = self._ifcond
1088            typ.check(schema)
1089            self.ifcond = typ.ifcond
1090        else:
1091            self.ifcond = listify_cond(self._ifcond)
1092
1093    def is_implicit(self):
1094        return not self.info
1095
1096    def visit(self, visitor):
1097        pass
1098
1099
1100class QAPISchemaVisitor(object):
1101    def visit_begin(self, schema):
1102        pass
1103
1104    def visit_end(self):
1105        pass
1106
1107    def visit_module(self, fname):
1108        pass
1109
1110    def visit_needed(self, entity):
1111        # Default to visiting everything
1112        return True
1113
1114    def visit_include(self, fname, info):
1115        pass
1116
1117    def visit_builtin_type(self, name, info, json_type):
1118        pass
1119
1120    def visit_enum_type(self, name, info, ifcond, members, prefix):
1121        pass
1122
1123    def visit_array_type(self, name, info, ifcond, element_type):
1124        pass
1125
1126    def visit_object_type(self, name, info, ifcond, base, members, variants):
1127        pass
1128
1129    def visit_object_type_flat(self, name, info, ifcond, members, variants):
1130        pass
1131
1132    def visit_alternate_type(self, name, info, ifcond, variants):
1133        pass
1134
1135    def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
1136                      success_response, boxed, allow_oob, allow_preconfig):
1137        pass
1138
1139    def visit_event(self, name, info, ifcond, arg_type, boxed):
1140        pass
1141
1142
1143class QAPISchemaInclude(QAPISchemaEntity):
1144
1145    def __init__(self, fname, info):
1146        QAPISchemaEntity.__init__(self, None, info, None)
1147        self.fname = fname
1148
1149    def visit(self, visitor):
1150        visitor.visit_include(self.fname, self.info)
1151
1152
1153class QAPISchemaType(QAPISchemaEntity):
1154    # Return the C type for common use.
1155    # For the types we commonly box, this is a pointer type.
1156    def c_type(self):
1157        pass
1158
1159    # Return the C type to be used in a parameter list.
1160    def c_param_type(self):
1161        return self.c_type()
1162
1163    # Return the C type to be used where we suppress boxing.
1164    def c_unboxed_type(self):
1165        return self.c_type()
1166
1167    def json_type(self):
1168        pass
1169
1170    def alternate_qtype(self):
1171        json2qtype = {
1172            'null':    'QTYPE_QNULL',
1173            'string':  'QTYPE_QSTRING',
1174            'number':  'QTYPE_QNUM',
1175            'int':     'QTYPE_QNUM',
1176            'boolean': 'QTYPE_QBOOL',
1177            'object':  'QTYPE_QDICT'
1178        }
1179        return json2qtype.get(self.json_type())
1180
1181    def doc_type(self):
1182        if self.is_implicit():
1183            return None
1184        return self.name
1185
1186
1187class QAPISchemaBuiltinType(QAPISchemaType):
1188    def __init__(self, name, json_type, c_type):
1189        QAPISchemaType.__init__(self, name, None, None)
1190        assert not c_type or isinstance(c_type, str)
1191        assert json_type in ('string', 'number', 'int', 'boolean', 'null',
1192                             'value')
1193        self._json_type_name = json_type
1194        self._c_type_name = c_type
1195
1196    def c_name(self):
1197        return self.name
1198
1199    def c_type(self):
1200        return self._c_type_name
1201
1202    def c_param_type(self):
1203        if self.name == 'str':
1204            return 'const ' + self._c_type_name
1205        return self._c_type_name
1206
1207    def json_type(self):
1208        return self._json_type_name
1209
1210    def doc_type(self):
1211        return self.json_type()
1212
1213    def visit(self, visitor):
1214        visitor.visit_builtin_type(self.name, self.info, self.json_type())
1215
1216
1217class QAPISchemaEnumType(QAPISchemaType):
1218    def __init__(self, name, info, doc, ifcond, members, prefix):
1219        QAPISchemaType.__init__(self, name, info, doc, ifcond)
1220        for m in members:
1221            assert isinstance(m, QAPISchemaMember)
1222            m.set_owner(name)
1223        assert prefix is None or isinstance(prefix, str)
1224        self.members = members
1225        self.prefix = prefix
1226
1227    def check(self, schema):
1228        QAPISchemaType.check(self, schema)
1229        seen = {}
1230        for m in self.members:
1231            m.check_clash(self.info, seen)
1232            if self.doc:
1233                self.doc.connect_member(m)
1234
1235    def is_implicit(self):
1236        # See QAPISchema._make_implicit_enum_type() and ._def_predefineds()
1237        return self.name.endswith('Kind') or self.name == 'QType'
1238
1239    def c_type(self):
1240        return c_name(self.name)
1241
1242    def member_names(self):
1243        return [m.name for m in self.members]
1244
1245    def json_type(self):
1246        return 'string'
1247
1248    def visit(self, visitor):
1249        visitor.visit_enum_type(self.name, self.info, self.ifcond,
1250                                self.members, self.prefix)
1251
1252
1253class QAPISchemaArrayType(QAPISchemaType):
1254    def __init__(self, name, info, element_type):
1255        QAPISchemaType.__init__(self, name, info, None, None)
1256        assert isinstance(element_type, str)
1257        self._element_type_name = element_type
1258        self.element_type = None
1259
1260    def check(self, schema):
1261        QAPISchemaType.check(self, schema)
1262        self.element_type = schema.lookup_type(self._element_type_name)
1263        assert self.element_type
1264        self.element_type.check(schema)
1265        self.ifcond = self.element_type.ifcond
1266
1267    def is_implicit(self):
1268        return True
1269
1270    def c_type(self):
1271        return c_name(self.name) + pointer_suffix
1272
1273    def json_type(self):
1274        return 'array'
1275
1276    def doc_type(self):
1277        elt_doc_type = self.element_type.doc_type()
1278        if not elt_doc_type:
1279            return None
1280        return 'array of ' + elt_doc_type
1281
1282    def visit(self, visitor):
1283        visitor.visit_array_type(self.name, self.info, self.ifcond,
1284                                 self.element_type)
1285
1286
1287class QAPISchemaObjectType(QAPISchemaType):
1288    def __init__(self, name, info, doc, ifcond,
1289                 base, local_members, variants):
1290        # struct has local_members, optional base, and no variants
1291        # flat union has base, variants, and no local_members
1292        # simple union has local_members, variants, and no base
1293        QAPISchemaType.__init__(self, name, info, doc, ifcond)
1294        assert base is None or isinstance(base, str)
1295        for m in local_members:
1296            assert isinstance(m, QAPISchemaObjectTypeMember)
1297            m.set_owner(name)
1298        if variants is not None:
1299            assert isinstance(variants, QAPISchemaObjectTypeVariants)
1300            variants.set_owner(name)
1301        self._base_name = base
1302        self.base = None
1303        self.local_members = local_members
1304        self.variants = variants
1305        self.members = None
1306
1307    def check(self, schema):
1308        QAPISchemaType.check(self, schema)
1309        if self.members is False:               # check for cycles
1310            raise QAPISemError(self.info,
1311                               "Object %s contains itself" % self.name)
1312        if self.members:
1313            return
1314        self.members = False                    # mark as being checked
1315        seen = OrderedDict()
1316        if self._base_name:
1317            self.base = schema.lookup_type(self._base_name)
1318            assert isinstance(self.base, QAPISchemaObjectType)
1319            self.base.check(schema)
1320            self.base.check_clash(self.info, seen)
1321        for m in self.local_members:
1322            m.check(schema)
1323            m.check_clash(self.info, seen)
1324            if self.doc:
1325                self.doc.connect_member(m)
1326        self.members = seen.values()
1327        if self.variants:
1328            self.variants.check(schema, seen)
1329            assert self.variants.tag_member in self.members
1330            self.variants.check_clash(self.info, seen)
1331        if self.doc:
1332            self.doc.check()
1333
1334    # Check that the members of this type do not cause duplicate JSON members,
1335    # and update seen to track the members seen so far. Report any errors
1336    # on behalf of info, which is not necessarily self.info
1337    def check_clash(self, info, seen):
1338        assert not self.variants       # not implemented
1339        for m in self.members:
1340            m.check_clash(info, seen)
1341
1342    def is_implicit(self):
1343        # See QAPISchema._make_implicit_object_type(), as well as
1344        # _def_predefineds()
1345        return self.name.startswith('q_')
1346
1347    def is_empty(self):
1348        assert self.members is not None
1349        return not self.members and not self.variants
1350
1351    def c_name(self):
1352        assert self.name != 'q_empty'
1353        return QAPISchemaType.c_name(self)
1354
1355    def c_type(self):
1356        assert not self.is_implicit()
1357        return c_name(self.name) + pointer_suffix
1358
1359    def c_unboxed_type(self):
1360        return c_name(self.name)
1361
1362    def json_type(self):
1363        return 'object'
1364
1365    def visit(self, visitor):
1366        visitor.visit_object_type(self.name, self.info, self.ifcond,
1367                                  self.base, self.local_members, self.variants)
1368        visitor.visit_object_type_flat(self.name, self.info, self.ifcond,
1369                                       self.members, self.variants)
1370
1371
1372class QAPISchemaMember(object):
1373    role = 'member'
1374
1375    def __init__(self, name, ifcond=None):
1376        assert isinstance(name, str)
1377        self.name = name
1378        self.ifcond = listify_cond(ifcond)
1379        self.owner = None
1380
1381    def set_owner(self, name):
1382        assert not self.owner
1383        self.owner = name
1384
1385    def check_clash(self, info, seen):
1386        cname = c_name(self.name)
1387        if cname.lower() != cname and self.owner not in name_case_whitelist:
1388            raise QAPISemError(info,
1389                               "%s should not use uppercase" % self.describe())
1390        if cname in seen:
1391            raise QAPISemError(info, "%s collides with %s" %
1392                               (self.describe(), seen[cname].describe()))
1393        seen[cname] = self
1394
1395    def _pretty_owner(self):
1396        owner = self.owner
1397        if owner.startswith('q_obj_'):
1398            # See QAPISchema._make_implicit_object_type() - reverse the
1399            # mapping there to create a nice human-readable description
1400            owner = owner[6:]
1401            if owner.endswith('-arg'):
1402                return '(parameter of %s)' % owner[:-4]
1403            elif owner.endswith('-base'):
1404                return '(base of %s)' % owner[:-5]
1405            else:
1406                assert owner.endswith('-wrapper')
1407                # Unreachable and not implemented
1408                assert False
1409        if owner.endswith('Kind'):
1410            # See QAPISchema._make_implicit_enum_type()
1411            return '(branch of %s)' % owner[:-4]
1412        return '(%s of %s)' % (self.role, owner)
1413
1414    def describe(self):
1415        return "'%s' %s" % (self.name, self._pretty_owner())
1416
1417
1418class QAPISchemaObjectTypeMember(QAPISchemaMember):
1419    def __init__(self, name, typ, optional, ifcond=None):
1420        QAPISchemaMember.__init__(self, name, ifcond)
1421        assert isinstance(typ, str)
1422        assert isinstance(optional, bool)
1423        self._type_name = typ
1424        self.type = None
1425        self.optional = optional
1426
1427    def check(self, schema):
1428        assert self.owner
1429        self.type = schema.lookup_type(self._type_name)
1430        assert self.type
1431
1432
1433class QAPISchemaObjectTypeVariants(object):
1434    def __init__(self, tag_name, tag_member, variants):
1435        # Flat unions pass tag_name but not tag_member.
1436        # Simple unions and alternates pass tag_member but not tag_name.
1437        # After check(), tag_member is always set, and tag_name remains
1438        # a reliable witness of being used by a flat union.
1439        assert bool(tag_member) != bool(tag_name)
1440        assert (isinstance(tag_name, str) or
1441                isinstance(tag_member, QAPISchemaObjectTypeMember))
1442        assert len(variants) > 0
1443        for v in variants:
1444            assert isinstance(v, QAPISchemaObjectTypeVariant)
1445        self._tag_name = tag_name
1446        self.tag_member = tag_member
1447        self.variants = variants
1448
1449    def set_owner(self, name):
1450        for v in self.variants:
1451            v.set_owner(name)
1452
1453    def check(self, schema, seen):
1454        if not self.tag_member:    # flat union
1455            self.tag_member = seen[c_name(self._tag_name)]
1456            assert self._tag_name == self.tag_member.name
1457        assert isinstance(self.tag_member.type, QAPISchemaEnumType)
1458        if self._tag_name:    # flat union
1459            # branches that are not explicitly covered get an empty type
1460            cases = set([v.name for v in self.variants])
1461            for m in self.tag_member.type.members:
1462                if m.name not in cases:
1463                    v = QAPISchemaObjectTypeVariant(m.name, 'q_empty')
1464                    v.set_owner(self.tag_member.owner)
1465                    self.variants.append(v)
1466        for v in self.variants:
1467            v.check(schema)
1468            # Union names must match enum values; alternate names are
1469            # checked separately. Use 'seen' to tell the two apart.
1470            if seen:
1471                assert v.name in self.tag_member.type.member_names()
1472                assert isinstance(v.type, QAPISchemaObjectType)
1473                v.type.check(schema)
1474
1475    def check_clash(self, info, seen):
1476        for v in self.variants:
1477            # Reset seen map for each variant, since qapi names from one
1478            # branch do not affect another branch
1479            assert isinstance(v.type, QAPISchemaObjectType)
1480            v.type.check_clash(info, dict(seen))
1481
1482
1483class QAPISchemaObjectTypeVariant(QAPISchemaObjectTypeMember):
1484    role = 'branch'
1485
1486    def __init__(self, name, typ):
1487        QAPISchemaObjectTypeMember.__init__(self, name, typ, False)
1488
1489
1490class QAPISchemaAlternateType(QAPISchemaType):
1491    def __init__(self, name, info, doc, ifcond, variants):
1492        QAPISchemaType.__init__(self, name, info, doc, ifcond)
1493        assert isinstance(variants, QAPISchemaObjectTypeVariants)
1494        assert variants.tag_member
1495        variants.set_owner(name)
1496        variants.tag_member.set_owner(self.name)
1497        self.variants = variants
1498
1499    def check(self, schema):
1500        QAPISchemaType.check(self, schema)
1501        self.variants.tag_member.check(schema)
1502        # Not calling self.variants.check_clash(), because there's nothing
1503        # to clash with
1504        self.variants.check(schema, {})
1505        # Alternate branch names have no relation to the tag enum values;
1506        # so we have to check for potential name collisions ourselves.
1507        seen = {}
1508        for v in self.variants.variants:
1509            v.check_clash(self.info, seen)
1510            if self.doc:
1511                self.doc.connect_member(v)
1512        if self.doc:
1513            self.doc.check()
1514
1515    def c_type(self):
1516        return c_name(self.name) + pointer_suffix
1517
1518    def json_type(self):
1519        return 'value'
1520
1521    def visit(self, visitor):
1522        visitor.visit_alternate_type(self.name, self.info, self.ifcond,
1523                                     self.variants)
1524
1525    def is_empty(self):
1526        return False
1527
1528
1529class QAPISchemaCommand(QAPISchemaEntity):
1530    def __init__(self, name, info, doc, ifcond, arg_type, ret_type,
1531                 gen, success_response, boxed, allow_oob, allow_preconfig):
1532        QAPISchemaEntity.__init__(self, name, info, doc, ifcond)
1533        assert not arg_type or isinstance(arg_type, str)
1534        assert not ret_type or isinstance(ret_type, str)
1535        self._arg_type_name = arg_type
1536        self.arg_type = None
1537        self._ret_type_name = ret_type
1538        self.ret_type = None
1539        self.gen = gen
1540        self.success_response = success_response
1541        self.boxed = boxed
1542        self.allow_oob = allow_oob
1543        self.allow_preconfig = allow_preconfig
1544
1545    def check(self, schema):
1546        QAPISchemaEntity.check(self, schema)
1547        if self._arg_type_name:
1548            self.arg_type = schema.lookup_type(self._arg_type_name)
1549            assert (isinstance(self.arg_type, QAPISchemaObjectType) or
1550                    isinstance(self.arg_type, QAPISchemaAlternateType))
1551            self.arg_type.check(schema)
1552            if self.boxed:
1553                if self.arg_type.is_empty():
1554                    raise QAPISemError(self.info,
1555                                       "Cannot use 'boxed' with empty type")
1556            else:
1557                assert not isinstance(self.arg_type, QAPISchemaAlternateType)
1558                assert not self.arg_type.variants
1559        elif self.boxed:
1560            raise QAPISemError(self.info, "Use of 'boxed' requires 'data'")
1561        if self._ret_type_name:
1562            self.ret_type = schema.lookup_type(self._ret_type_name)
1563            assert isinstance(self.ret_type, QAPISchemaType)
1564
1565    def visit(self, visitor):
1566        visitor.visit_command(self.name, self.info, self.ifcond,
1567                              self.arg_type, self.ret_type,
1568                              self.gen, self.success_response,
1569                              self.boxed, self.allow_oob,
1570                              self.allow_preconfig)
1571
1572
1573class QAPISchemaEvent(QAPISchemaEntity):
1574    def __init__(self, name, info, doc, ifcond, arg_type, boxed):
1575        QAPISchemaEntity.__init__(self, name, info, doc, ifcond)
1576        assert not arg_type or isinstance(arg_type, str)
1577        self._arg_type_name = arg_type
1578        self.arg_type = None
1579        self.boxed = boxed
1580
1581    def check(self, schema):
1582        QAPISchemaEntity.check(self, schema)
1583        if self._arg_type_name:
1584            self.arg_type = schema.lookup_type(self._arg_type_name)
1585            assert (isinstance(self.arg_type, QAPISchemaObjectType) or
1586                    isinstance(self.arg_type, QAPISchemaAlternateType))
1587            self.arg_type.check(schema)
1588            if self.boxed:
1589                if self.arg_type.is_empty():
1590                    raise QAPISemError(self.info,
1591                                       "Cannot use 'boxed' with empty type")
1592            else:
1593                assert not isinstance(self.arg_type, QAPISchemaAlternateType)
1594                assert not self.arg_type.variants
1595        elif self.boxed:
1596            raise QAPISemError(self.info, "Use of 'boxed' requires 'data'")
1597
1598    def visit(self, visitor):
1599        visitor.visit_event(self.name, self.info, self.ifcond,
1600                            self.arg_type, self.boxed)
1601
1602
1603class QAPISchema(object):
1604    def __init__(self, fname):
1605        self._fname = fname
1606        if sys.version_info[0] >= 3:
1607            f = open(fname, 'r', encoding='utf-8')
1608        else:
1609            f = open(fname, 'r')
1610        parser = QAPISchemaParser(f)
1611        exprs = check_exprs(parser.exprs)
1612        self.docs = parser.docs
1613        self._entity_list = []
1614        self._entity_dict = {}
1615        self._predefining = True
1616        self._def_predefineds()
1617        self._predefining = False
1618        self._def_exprs(exprs)
1619        self.check()
1620
1621    def _def_entity(self, ent):
1622        # Only the predefined types are allowed to not have info
1623        assert ent.info or self._predefining
1624        assert ent.name is None or ent.name not in self._entity_dict
1625        self._entity_list.append(ent)
1626        if ent.name is not None:
1627            self._entity_dict[ent.name] = ent
1628        if ent.info:
1629            ent.module = os.path.relpath(ent.info['file'],
1630                                         os.path.dirname(self._fname))
1631
1632    def lookup_entity(self, name, typ=None):
1633        ent = self._entity_dict.get(name)
1634        if typ and not isinstance(ent, typ):
1635            return None
1636        return ent
1637
1638    def lookup_type(self, name):
1639        return self.lookup_entity(name, QAPISchemaType)
1640
1641    def _def_include(self, expr, info, doc):
1642        include = expr['include']
1643        assert doc is None
1644        main_info = info
1645        while main_info['parent']:
1646            main_info = main_info['parent']
1647        fname = os.path.relpath(include, os.path.dirname(main_info['file']))
1648        self._def_entity(QAPISchemaInclude(fname, info))
1649
1650    def _def_builtin_type(self, name, json_type, c_type):
1651        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
1652        # Instantiating only the arrays that are actually used would
1653        # be nice, but we can't as long as their generated code
1654        # (qapi-builtin-types.[ch]) may be shared by some other
1655        # schema.
1656        self._make_array_type(name, None)
1657
1658    def _def_predefineds(self):
1659        for t in [('str',    'string',  'char' + pointer_suffix),
1660                  ('number', 'number',  'double'),
1661                  ('int',    'int',     'int64_t'),
1662                  ('int8',   'int',     'int8_t'),
1663                  ('int16',  'int',     'int16_t'),
1664                  ('int32',  'int',     'int32_t'),
1665                  ('int64',  'int',     'int64_t'),
1666                  ('uint8',  'int',     'uint8_t'),
1667                  ('uint16', 'int',     'uint16_t'),
1668                  ('uint32', 'int',     'uint32_t'),
1669                  ('uint64', 'int',     'uint64_t'),
1670                  ('size',   'int',     'uint64_t'),
1671                  ('bool',   'boolean', 'bool'),
1672                  ('any',    'value',   'QObject' + pointer_suffix),
1673                  ('null',   'null',    'QNull' + pointer_suffix)]:
1674            self._def_builtin_type(*t)
1675        self.the_empty_object_type = QAPISchemaObjectType(
1676            'q_empty', None, None, None, None, [], None)
1677        self._def_entity(self.the_empty_object_type)
1678
1679        qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
1680                  'qbool']
1681        qtype_values = self._make_enum_members([{'name': n} for n in qtypes])
1682
1683        self._def_entity(QAPISchemaEnumType('QType', None, None, None,
1684                                            qtype_values, 'QTYPE'))
1685
1686    def _make_enum_members(self, values):
1687        return [QAPISchemaMember(v['name'], v.get('if')) for v in values]
1688
1689    def _make_implicit_enum_type(self, name, info, ifcond, values):
1690        # See also QAPISchemaObjectTypeMember._pretty_owner()
1691        name = name + 'Kind'   # Use namespace reserved by add_name()
1692        self._def_entity(QAPISchemaEnumType(
1693            name, info, None, ifcond, self._make_enum_members(values), None))
1694        return name
1695
1696    def _make_array_type(self, element_type, info):
1697        name = element_type + 'List'   # Use namespace reserved by add_name()
1698        if not self.lookup_type(name):
1699            self._def_entity(QAPISchemaArrayType(name, info, element_type))
1700        return name
1701
1702    def _make_implicit_object_type(self, name, info, doc, ifcond,
1703                                   role, members):
1704        if not members:
1705            return None
1706        # See also QAPISchemaObjectTypeMember._pretty_owner()
1707        name = 'q_obj_%s-%s' % (name, role)
1708        typ = self.lookup_entity(name, QAPISchemaObjectType)
1709        if typ:
1710            # The implicit object type has multiple users.  This can
1711            # happen only for simple unions' implicit wrapper types.
1712            # Its ifcond should be the disjunction of its user's
1713            # ifconds.  Not implemented.  Instead, we always pass the
1714            # wrapped type's ifcond, which is trivially the same for all
1715            # users.  It's also necessary for the wrapper to compile.
1716            # But it's not tight: the disjunction need not imply it.  We
1717            # may end up compiling useless wrapper types.
1718            # TODO kill simple unions or implement the disjunction
1719            assert ifcond == typ._ifcond # pylint: disable=protected-access
1720        else:
1721            self._def_entity(QAPISchemaObjectType(name, info, doc, ifcond,
1722                                                  None, members, None))
1723        return name
1724
1725    def _def_enum_type(self, expr, info, doc):
1726        name = expr['enum']
1727        data = expr['data']
1728        prefix = expr.get('prefix')
1729        ifcond = expr.get('if')
1730        self._def_entity(QAPISchemaEnumType(
1731            name, info, doc, ifcond,
1732            self._make_enum_members(data), prefix))
1733
1734    def _make_member(self, name, typ, ifcond, info):
1735        optional = False
1736        if name.startswith('*'):
1737            name = name[1:]
1738            optional = True
1739        if isinstance(typ, list):
1740            assert len(typ) == 1
1741            typ = self._make_array_type(typ[0], info)
1742        return QAPISchemaObjectTypeMember(name, typ, optional, ifcond)
1743
1744    def _make_members(self, data, info):
1745        return [self._make_member(key, value['type'], value.get('if'), info)
1746                for (key, value) in data.items()]
1747
1748    def _def_struct_type(self, expr, info, doc):
1749        name = expr['struct']
1750        base = expr.get('base')
1751        data = expr['data']
1752        ifcond = expr.get('if')
1753        self._def_entity(QAPISchemaObjectType(name, info, doc, ifcond, base,
1754                                              self._make_members(data, info),
1755                                              None))
1756
1757    def _make_variant(self, case, typ):
1758        return QAPISchemaObjectTypeVariant(case, typ)
1759
1760    def _make_simple_variant(self, case, typ, info):
1761        if isinstance(typ, list):
1762            assert len(typ) == 1
1763            typ = self._make_array_type(typ[0], info)
1764        typ = self._make_implicit_object_type(
1765            typ, info, None, self.lookup_type(typ),
1766            'wrapper', [self._make_member('data', typ, None, info)])
1767        return QAPISchemaObjectTypeVariant(case, typ)
1768
1769    def _def_union_type(self, expr, info, doc):
1770        name = expr['union']
1771        data = expr['data']
1772        base = expr.get('base')
1773        ifcond = expr.get('if')
1774        tag_name = expr.get('discriminator')
1775        tag_member = None
1776        if isinstance(base, dict):
1777            base = self._make_implicit_object_type(
1778                name, info, doc, ifcond,
1779                'base', self._make_members(base, info))
1780        if tag_name:
1781            variants = [self._make_variant(key, value['type'])
1782                        for (key, value) in data.items()]
1783            members = []
1784        else:
1785            variants = [self._make_simple_variant(key, value['type'], info)
1786                        for (key, value) in data.items()]
1787            enum = [{'name': v.name} for v in variants]
1788            typ = self._make_implicit_enum_type(name, info, ifcond, enum)
1789            tag_member = QAPISchemaObjectTypeMember('type', typ, False)
1790            members = [tag_member]
1791        self._def_entity(
1792            QAPISchemaObjectType(name, info, doc, ifcond, base, members,
1793                                 QAPISchemaObjectTypeVariants(tag_name,
1794                                                              tag_member,
1795                                                              variants)))
1796
1797    def _def_alternate_type(self, expr, info, doc):
1798        name = expr['alternate']
1799        data = expr['data']
1800        ifcond = expr.get('if')
1801        variants = [self._make_variant(key, value['type'])
1802                    for (key, value) in data.items()]
1803        tag_member = QAPISchemaObjectTypeMember('type', 'QType', False)
1804        self._def_entity(
1805            QAPISchemaAlternateType(name, info, doc, ifcond,
1806                                    QAPISchemaObjectTypeVariants(None,
1807                                                                 tag_member,
1808                                                                 variants)))
1809
1810    def _def_command(self, expr, info, doc):
1811        name = expr['command']
1812        data = expr.get('data')
1813        rets = expr.get('returns')
1814        gen = expr.get('gen', True)
1815        success_response = expr.get('success-response', True)
1816        boxed = expr.get('boxed', False)
1817        allow_oob = expr.get('allow-oob', False)
1818        allow_preconfig = expr.get('allow-preconfig', False)
1819        ifcond = expr.get('if')
1820        if isinstance(data, OrderedDict):
1821            data = self._make_implicit_object_type(
1822                name, info, doc, ifcond, 'arg', self._make_members(data, info))
1823        if isinstance(rets, list):
1824            assert len(rets) == 1
1825            rets = self._make_array_type(rets[0], info)
1826        self._def_entity(QAPISchemaCommand(name, info, doc, ifcond, data, rets,
1827                                           gen, success_response,
1828                                           boxed, allow_oob, allow_preconfig))
1829
1830    def _def_event(self, expr, info, doc):
1831        name = expr['event']
1832        data = expr.get('data')
1833        boxed = expr.get('boxed', False)
1834        ifcond = expr.get('if')
1835        if isinstance(data, OrderedDict):
1836            data = self._make_implicit_object_type(
1837                name, info, doc, ifcond, 'arg', self._make_members(data, info))
1838        self._def_entity(QAPISchemaEvent(name, info, doc, ifcond, data, boxed))
1839
1840    def _def_exprs(self, exprs):
1841        for expr_elem in exprs:
1842            expr = expr_elem['expr']
1843            info = expr_elem['info']
1844            doc = expr_elem.get('doc')
1845            if 'enum' in expr:
1846                self._def_enum_type(expr, info, doc)
1847            elif 'struct' in expr:
1848                self._def_struct_type(expr, info, doc)
1849            elif 'union' in expr:
1850                self._def_union_type(expr, info, doc)
1851            elif 'alternate' in expr:
1852                self._def_alternate_type(expr, info, doc)
1853            elif 'command' in expr:
1854                self._def_command(expr, info, doc)
1855            elif 'event' in expr:
1856                self._def_event(expr, info, doc)
1857            elif 'include' in expr:
1858                self._def_include(expr, info, doc)
1859            else:
1860                assert False
1861
1862    def check(self):
1863        for ent in self._entity_list:
1864            ent.check(self)
1865
1866    def visit(self, visitor):
1867        visitor.visit_begin(self)
1868        module = None
1869        for entity in self._entity_list:
1870            if visitor.visit_needed(entity):
1871                if entity.module != module:
1872                    module = entity.module
1873                    visitor.visit_module(module)
1874                entity.visit(visitor)
1875        visitor.visit_end()
1876
1877
1878#
1879# Code generation helpers
1880#
1881
1882def camel_case(name):
1883    new_name = ''
1884    first = True
1885    for ch in name:
1886        if ch in ['_', '-']:
1887            first = True
1888        elif first:
1889            new_name += ch.upper()
1890            first = False
1891        else:
1892            new_name += ch.lower()
1893    return new_name
1894
1895
1896# ENUMName -> ENUM_NAME, EnumName1 -> ENUM_NAME1
1897# ENUM_NAME -> ENUM_NAME, ENUM_NAME1 -> ENUM_NAME1, ENUM_Name2 -> ENUM_NAME2
1898# ENUM24_Name -> ENUM24_NAME
1899def camel_to_upper(value):
1900    c_fun_str = c_name(value, False)
1901    if value.isupper():
1902        return c_fun_str
1903
1904    new_name = ''
1905    length = len(c_fun_str)
1906    for i in range(length):
1907        c = c_fun_str[i]
1908        # When c is upper and no '_' appears before, do more checks
1909        if c.isupper() and (i > 0) and c_fun_str[i - 1] != '_':
1910            if i < length - 1 and c_fun_str[i + 1].islower():
1911                new_name += '_'
1912            elif c_fun_str[i - 1].isdigit():
1913                new_name += '_'
1914        new_name += c
1915    return new_name.lstrip('_').upper()
1916
1917
1918def c_enum_const(type_name, const_name, prefix=None):
1919    if prefix is not None:
1920        type_name = prefix
1921    return camel_to_upper(type_name) + '_' + c_name(const_name, False).upper()
1922
1923
1924if hasattr(str, 'maketrans'):
1925    c_name_trans = str.maketrans('.-', '__')
1926else:
1927    c_name_trans = string.maketrans('.-', '__')
1928
1929
1930# Map @name to a valid C identifier.
1931# If @protect, avoid returning certain ticklish identifiers (like
1932# C keywords) by prepending 'q_'.
1933#
1934# Used for converting 'name' from a 'name':'type' qapi definition
1935# into a generated struct member, as well as converting type names
1936# into substrings of a generated C function name.
1937# '__a.b_c' -> '__a_b_c', 'x-foo' -> 'x_foo'
1938# protect=True: 'int' -> 'q_int'; protect=False: 'int' -> 'int'
1939def c_name(name, protect=True):
1940    # ANSI X3J11/88-090, 3.1.1
1941    c89_words = set(['auto', 'break', 'case', 'char', 'const', 'continue',
1942                     'default', 'do', 'double', 'else', 'enum', 'extern',
1943                     'float', 'for', 'goto', 'if', 'int', 'long', 'register',
1944                     'return', 'short', 'signed', 'sizeof', 'static',
1945                     'struct', 'switch', 'typedef', 'union', 'unsigned',
1946                     'void', 'volatile', 'while'])
1947    # ISO/IEC 9899:1999, 6.4.1
1948    c99_words = set(['inline', 'restrict', '_Bool', '_Complex', '_Imaginary'])
1949    # ISO/IEC 9899:2011, 6.4.1
1950    c11_words = set(['_Alignas', '_Alignof', '_Atomic', '_Generic',
1951                     '_Noreturn', '_Static_assert', '_Thread_local'])
1952    # GCC http://gcc.gnu.org/onlinedocs/gcc-4.7.1/gcc/C-Extensions.html
1953    # excluding _.*
1954    gcc_words = set(['asm', 'typeof'])
1955    # C++ ISO/IEC 14882:2003 2.11
1956    cpp_words = set(['bool', 'catch', 'class', 'const_cast', 'delete',
1957                     'dynamic_cast', 'explicit', 'false', 'friend', 'mutable',
1958                     'namespace', 'new', 'operator', 'private', 'protected',
1959                     'public', 'reinterpret_cast', 'static_cast', 'template',
1960                     'this', 'throw', 'true', 'try', 'typeid', 'typename',
1961                     'using', 'virtual', 'wchar_t',
1962                     # alternative representations
1963                     'and', 'and_eq', 'bitand', 'bitor', 'compl', 'not',
1964                     'not_eq', 'or', 'or_eq', 'xor', 'xor_eq'])
1965    # namespace pollution:
1966    polluted_words = set(['unix', 'errno', 'mips', 'sparc', 'i386'])
1967    name = name.translate(c_name_trans)
1968    if protect and (name in c89_words | c99_words | c11_words | gcc_words
1969                    | cpp_words | polluted_words):
1970        return 'q_' + name
1971    return name
1972
1973
1974eatspace = '\033EATSPACE.'
1975pointer_suffix = ' *' + eatspace
1976
1977
1978def genindent(count):
1979    ret = ''
1980    for _ in range(count):
1981        ret += ' '
1982    return ret
1983
1984
1985indent_level = 0
1986
1987
1988def push_indent(indent_amount=4):
1989    global indent_level
1990    indent_level += indent_amount
1991
1992
1993def pop_indent(indent_amount=4):
1994    global indent_level
1995    indent_level -= indent_amount
1996
1997
1998# Generate @code with @kwds interpolated.
1999# Obey indent_level, and strip eatspace.
2000def cgen(code, **kwds):
2001    raw = code % kwds
2002    if indent_level:
2003        indent = genindent(indent_level)
2004        # re.subn() lacks flags support before Python 2.7, use re.compile()
2005        raw = re.subn(re.compile(r'^(?!(#|$))', re.MULTILINE),
2006                      indent, raw)
2007        raw = raw[0]
2008    return re.sub(re.escape(eatspace) + r' *', '', raw)
2009
2010
2011def mcgen(code, **kwds):
2012    if code[0] == '\n':
2013        code = code[1:]
2014    return cgen(code, **kwds)
2015
2016
2017def guardname(filename):
2018    return re.sub(r'[^A-Za-z0-9_]', '_', filename).upper()
2019
2020
2021def guardstart(name):
2022    return mcgen('''
2023#ifndef %(name)s
2024#define %(name)s
2025
2026''',
2027                 name=guardname(name))
2028
2029
2030def guardend(name):
2031    return mcgen('''
2032
2033#endif /* %(name)s */
2034''',
2035                 name=guardname(name))
2036
2037
2038def gen_if(ifcond):
2039    ret = ''
2040    for ifc in ifcond:
2041        ret += mcgen('''
2042#if %(cond)s
2043''', cond=ifc)
2044    return ret
2045
2046
2047def gen_endif(ifcond):
2048    ret = ''
2049    for ifc in reversed(ifcond):
2050        ret += mcgen('''
2051#endif /* %(cond)s */
2052''', cond=ifc)
2053    return ret
2054
2055
2056def _wrap_ifcond(ifcond, before, after):
2057    if before == after:
2058        return after   # suppress empty #if ... #endif
2059
2060    assert after.startswith(before)
2061    out = before
2062    added = after[len(before):]
2063    if added[0] == '\n':
2064        out += '\n'
2065        added = added[1:]
2066    out += gen_if(ifcond)
2067    out += added
2068    out += gen_endif(ifcond)
2069    return out
2070
2071
2072def gen_enum_lookup(name, members, prefix=None):
2073    ret = mcgen('''
2074
2075const QEnumLookup %(c_name)s_lookup = {
2076    .array = (const char *const[]) {
2077''',
2078                c_name=c_name(name))
2079    for m in members:
2080        index = c_enum_const(name, m.name, prefix)
2081        ret += mcgen('''
2082        [%(index)s] = "%(name)s",
2083''',
2084                     index=index, name=m.name)
2085
2086    ret += mcgen('''
2087    },
2088    .size = %(max_index)s
2089};
2090''',
2091                 max_index=c_enum_const(name, '_MAX', prefix))
2092    return ret
2093
2094
2095def gen_enum(name, members, prefix=None):
2096    # append automatically generated _MAX value
2097    enum_members = members + [QAPISchemaMember('_MAX')]
2098
2099    ret = mcgen('''
2100
2101typedef enum %(c_name)s {
2102''',
2103                c_name=c_name(name))
2104
2105    for m in enum_members:
2106        ret += mcgen('''
2107    %(c_enum)s,
2108''',
2109                     c_enum=c_enum_const(name, m.name, prefix))
2110
2111    ret += mcgen('''
2112} %(c_name)s;
2113''',
2114                 c_name=c_name(name))
2115
2116    ret += mcgen('''
2117
2118#define %(c_name)s_str(val) \\
2119    qapi_enum_lookup(&%(c_name)s_lookup, (val))
2120
2121extern const QEnumLookup %(c_name)s_lookup;
2122''',
2123                 c_name=c_name(name))
2124    return ret
2125
2126
2127def build_params(arg_type, boxed, extra=None):
2128    ret = ''
2129    sep = ''
2130    if boxed:
2131        assert arg_type
2132        ret += '%s arg' % arg_type.c_param_type()
2133        sep = ', '
2134    elif arg_type:
2135        assert not arg_type.variants
2136        for memb in arg_type.members:
2137            ret += sep
2138            sep = ', '
2139            if memb.optional:
2140                ret += 'bool has_%s, ' % c_name(memb.name)
2141            ret += '%s %s' % (memb.type.c_param_type(),
2142                              c_name(memb.name))
2143    if extra:
2144        ret += sep + extra
2145    return ret if ret else 'void'
2146
2147
2148#
2149# Accumulate and write output
2150#
2151
2152class QAPIGen(object):
2153
2154    def __init__(self):
2155        self._preamble = ''
2156        self._body = ''
2157
2158    def preamble_add(self, text):
2159        self._preamble += text
2160
2161    def add(self, text):
2162        self._body += text
2163
2164    def get_content(self, fname=None):
2165        return (self._top(fname) + self._preamble + self._body
2166                + self._bottom(fname))
2167
2168    def _top(self, fname):
2169        return ''
2170
2171    def _bottom(self, fname):
2172        return ''
2173
2174    def write(self, output_dir, fname):
2175        pathname = os.path.join(output_dir, fname)
2176        dir = os.path.dirname(pathname)
2177        if dir:
2178            try:
2179                os.makedirs(dir)
2180            except os.error as e:
2181                if e.errno != errno.EEXIST:
2182                    raise
2183        fd = os.open(pathname, os.O_RDWR | os.O_CREAT, 0o666)
2184        if sys.version_info[0] >= 3:
2185            f = open(fd, 'r+', encoding='utf-8')
2186        else:
2187            f = os.fdopen(fd, 'r+')
2188        text = self.get_content(fname)
2189        oldtext = f.read(len(text) + 1)
2190        if text != oldtext:
2191            f.seek(0)
2192            f.truncate(0)
2193            f.write(text)
2194        f.close()
2195
2196
2197@contextmanager
2198def ifcontext(ifcond, *args):
2199    """A 'with' statement context manager to wrap with start_if()/end_if()
2200
2201    *args: any number of QAPIGenCCode
2202
2203    Example::
2204
2205        with ifcontext(ifcond, self._genh, self._genc):
2206            modify self._genh and self._genc ...
2207
2208    Is equivalent to calling::
2209
2210        self._genh.start_if(ifcond)
2211        self._genc.start_if(ifcond)
2212        modify self._genh and self._genc ...
2213        self._genh.end_if()
2214        self._genc.end_if()
2215    """
2216    for arg in args:
2217        arg.start_if(ifcond)
2218    yield
2219    for arg in args:
2220        arg.end_if()
2221
2222
2223class QAPIGenCCode(QAPIGen):
2224
2225    def __init__(self):
2226        QAPIGen.__init__(self)
2227        self._start_if = None
2228
2229    def start_if(self, ifcond):
2230        assert self._start_if is None
2231        self._start_if = (ifcond, self._body, self._preamble)
2232
2233    def end_if(self):
2234        assert self._start_if
2235        self._wrap_ifcond()
2236        self._start_if = None
2237
2238    def _wrap_ifcond(self):
2239        self._body = _wrap_ifcond(self._start_if[0],
2240                                  self._start_if[1], self._body)
2241        self._preamble = _wrap_ifcond(self._start_if[0],
2242                                      self._start_if[2], self._preamble)
2243
2244    def get_content(self, fname=None):
2245        assert self._start_if is None
2246        return QAPIGen.get_content(self, fname)
2247
2248
2249class QAPIGenC(QAPIGenCCode):
2250
2251    def __init__(self, blurb, pydoc):
2252        QAPIGenCCode.__init__(self)
2253        self._blurb = blurb
2254        self._copyright = '\n * '.join(re.findall(r'^Copyright .*', pydoc,
2255                                                  re.MULTILINE))
2256
2257    def _top(self, fname):
2258        return mcgen('''
2259/* AUTOMATICALLY GENERATED, DO NOT MODIFY */
2260
2261/*
2262%(blurb)s
2263 *
2264 * %(copyright)s
2265 *
2266 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
2267 * See the COPYING.LIB file in the top-level directory.
2268 */
2269
2270''',
2271                     blurb=self._blurb, copyright=self._copyright)
2272
2273    def _bottom(self, fname):
2274        return mcgen('''
2275
2276/* Dummy declaration to prevent empty .o file */
2277char dummy_%(name)s;
2278''',
2279                     name=c_name(fname))
2280
2281
2282class QAPIGenH(QAPIGenC):
2283
2284    def _top(self, fname):
2285        return QAPIGenC._top(self, fname) + guardstart(fname)
2286
2287    def _bottom(self, fname):
2288        return guardend(fname)
2289
2290
2291class QAPIGenDoc(QAPIGen):
2292
2293    def _top(self, fname):
2294        return (QAPIGen._top(self, fname)
2295                + '@c AUTOMATICALLY GENERATED, DO NOT MODIFY\n\n')
2296
2297
2298class QAPISchemaMonolithicCVisitor(QAPISchemaVisitor):
2299
2300    def __init__(self, prefix, what, blurb, pydoc):
2301        self._prefix = prefix
2302        self._what = what
2303        self._genc = QAPIGenC(blurb, pydoc)
2304        self._genh = QAPIGenH(blurb, pydoc)
2305
2306    def write(self, output_dir):
2307        self._genc.write(output_dir, self._prefix + self._what + '.c')
2308        self._genh.write(output_dir, self._prefix + self._what + '.h')
2309
2310
2311class QAPISchemaModularCVisitor(QAPISchemaVisitor):
2312
2313    def __init__(self, prefix, what, blurb, pydoc):
2314        self._prefix = prefix
2315        self._what = what
2316        self._blurb = blurb
2317        self._pydoc = pydoc
2318        self._module = {}
2319        self._main_module = None
2320
2321    def _module_basename(self, what, name):
2322        if name is None:
2323            return re.sub(r'-', '-builtin-', what)
2324        basename = os.path.join(os.path.dirname(name),
2325                                self._prefix + what)
2326        if name == self._main_module:
2327            return basename
2328        return basename + '-' + os.path.splitext(os.path.basename(name))[0]
2329
2330    def _add_module(self, name, blurb):
2331        if self._main_module is None and name is not None:
2332            self._main_module = name
2333        genc = QAPIGenC(blurb, self._pydoc)
2334        genh = QAPIGenH(blurb, self._pydoc)
2335        self._module[name] = (genc, genh)
2336        self._set_module(name)
2337
2338    def _set_module(self, name):
2339        self._genc, self._genh = self._module[name]
2340
2341    def write(self, output_dir, opt_builtins=False):
2342        for name in self._module:
2343            if name is None and not opt_builtins:
2344                continue
2345            basename = self._module_basename(self._what, name)
2346            (genc, genh) = self._module[name]
2347            genc.write(output_dir, basename + '.c')
2348            genh.write(output_dir, basename + '.h')
2349
2350    def _begin_module(self, name):
2351        pass
2352
2353    def visit_module(self, name):
2354        if name in self._module:
2355            self._set_module(name)
2356            return
2357        self._add_module(name, self._blurb)
2358        self._begin_module(name)
2359
2360    def visit_include(self, name, info):
2361        basename = self._module_basename(self._what, name)
2362        self._genh.preamble_add(mcgen('''
2363#include "%(basename)s.h"
2364''',
2365                                      basename=basename))
2366