1# -*- coding: utf-8 -*- 2# 3# Check (context-free) QAPI schema expression structure 4# 5# Copyright IBM, Corp. 2011 6# Copyright (c) 2013-2019 Red Hat Inc. 7# 8# Authors: 9# Anthony Liguori <aliguori@us.ibm.com> 10# Markus Armbruster <armbru@redhat.com> 11# Eric Blake <eblake@redhat.com> 12# Marc-André Lureau <marcandre.lureau@redhat.com> 13# 14# This work is licensed under the terms of the GNU GPL, version 2. 15# See the COPYING file in the top-level directory. 16 17from collections import OrderedDict 18import re 19 20from .common import c_name 21from .error import QAPISemError 22 23 24# Names consist of letters, digits, -, and _, starting with a letter. 25# An experimental name is prefixed with x-. A name of a downstream 26# extension is prefixed with __RFQDN_. The latter prefix goes first. 27valid_name = re.compile(r'(__[a-z0-9.-]+_)?' 28 r'(x-)?' 29 r'([a-z][a-z0-9_-]*)$', re.IGNORECASE) 30 31 32def check_name_is_str(name, info, source): 33 if not isinstance(name, str): 34 raise QAPISemError(info, "%s requires a string name" % source) 35 36 37def check_name_str(name, info, source): 38 # Reserve the entire 'q_' namespace for c_name(), and for 'q_empty' 39 # and 'q_obj_*' implicit type names. 40 match = valid_name.match(name) 41 if not match or c_name(name, False).startswith('q_'): 42 raise QAPISemError(info, "%s has an invalid name" % source) 43 return match.group(3) 44 45 46def check_name_upper(name, info, source): 47 stem = check_name_str(name, info, source) 48 if re.search(r'[a-z-]', stem): 49 raise QAPISemError( 50 info, "name of %s must not use lowercase or '-'" % source) 51 52 53def check_name_lower(name, info, source, 54 permit_upper=False, 55 permit_underscore=False): 56 stem = check_name_str(name, info, source) 57 if ((not permit_upper and re.search(r'[A-Z]', stem)) 58 or (not permit_underscore and '_' in stem)): 59 raise QAPISemError( 60 info, "name of %s must not use uppercase or '_'" % source) 61 62 63def check_name_camel(name, info, source): 64 stem = check_name_str(name, info, source) 65 if not re.match(r'[A-Z][A-Za-z0-9]*[a-z][A-Za-z0-9]*$', stem): 66 raise QAPISemError(info, "name of %s must use CamelCase" % source) 67 68 69def check_defn_name_str(name, info, meta): 70 if meta == 'event': 71 check_name_upper(name, info, meta) 72 elif meta == 'command': 73 check_name_lower(name, info, meta, 74 permit_upper=True, permit_underscore=True) 75 else: 76 check_name_camel(name, info, meta) 77 if name.endswith('Kind') or name.endswith('List'): 78 raise QAPISemError( 79 info, "%s name should not end in '%s'" % (meta, name[-4:])) 80 81 82def check_keys(value, info, source, required, optional): 83 84 def pprint(elems): 85 return ', '.join("'" + e + "'" for e in sorted(elems)) 86 87 missing = set(required) - set(value) 88 if missing: 89 raise QAPISemError( 90 info, 91 "%s misses key%s %s" 92 % (source, 's' if len(missing) > 1 else '', 93 pprint(missing))) 94 allowed = set(required + optional) 95 unknown = set(value) - allowed 96 if unknown: 97 raise QAPISemError( 98 info, 99 "%s has unknown key%s %s\nValid keys are %s." 100 % (source, 's' if len(unknown) > 1 else '', 101 pprint(unknown), pprint(allowed))) 102 103 104def check_flags(expr, info): 105 for key in ['gen', 'success-response']: 106 if key in expr and expr[key] is not False: 107 raise QAPISemError( 108 info, "flag '%s' may only use false value" % key) 109 for key in ['boxed', 'allow-oob', 'allow-preconfig', 'coroutine']: 110 if key in expr and expr[key] is not True: 111 raise QAPISemError( 112 info, "flag '%s' may only use true value" % key) 113 if 'allow-oob' in expr and 'coroutine' in expr: 114 # This is not necessarily a fundamental incompatibility, but 115 # we don't have a use case and the desired semantics isn't 116 # obvious. The simplest solution is to forbid it until we get 117 # a use case for it. 118 raise QAPISemError(info, "flags 'allow-oob' and 'coroutine' " 119 "are incompatible") 120 121 122def check_if(expr, info, source): 123 124 def check_if_str(ifcond, info): 125 if not isinstance(ifcond, str): 126 raise QAPISemError( 127 info, 128 "'if' condition of %s must be a string or a list of strings" 129 % source) 130 if ifcond.strip() == '': 131 raise QAPISemError( 132 info, 133 "'if' condition '%s' of %s makes no sense" 134 % (ifcond, source)) 135 136 ifcond = expr.get('if') 137 if ifcond is None: 138 return 139 if isinstance(ifcond, list): 140 if ifcond == []: 141 raise QAPISemError( 142 info, "'if' condition [] of %s is useless" % source) 143 for elt in ifcond: 144 check_if_str(elt, info) 145 else: 146 check_if_str(ifcond, info) 147 expr['if'] = [ifcond] 148 149 150def normalize_members(members): 151 if isinstance(members, OrderedDict): 152 for key, arg in members.items(): 153 if isinstance(arg, dict): 154 continue 155 members[key] = {'type': arg} 156 157 158def check_type(value, info, source, 159 allow_array=False, allow_dict=False): 160 if value is None: 161 return 162 163 # Array type 164 if isinstance(value, list): 165 if not allow_array: 166 raise QAPISemError(info, "%s cannot be an array" % source) 167 if len(value) != 1 or not isinstance(value[0], str): 168 raise QAPISemError(info, 169 "%s: array type must contain single type name" % 170 source) 171 return 172 173 # Type name 174 if isinstance(value, str): 175 return 176 177 # Anonymous type 178 179 if not allow_dict: 180 raise QAPISemError(info, "%s should be a type name" % source) 181 182 if not isinstance(value, OrderedDict): 183 raise QAPISemError(info, 184 "%s should be an object or type name" % source) 185 186 permit_upper = allow_dict in info.pragma.member_name_exceptions 187 188 # value is a dictionary, check that each member is okay 189 for (key, arg) in value.items(): 190 key_source = "%s member '%s'" % (source, key) 191 if key.startswith('*'): 192 key = key[1:] 193 check_name_lower(key, info, key_source, 194 permit_upper, permit_underscore=True) 195 if c_name(key, False) == 'u' or c_name(key, False).startswith('has_'): 196 raise QAPISemError(info, "%s uses reserved name" % key_source) 197 check_keys(arg, info, key_source, ['type'], ['if', 'features']) 198 check_if(arg, info, key_source) 199 check_features(arg.get('features'), info) 200 check_type(arg['type'], info, key_source, allow_array=True) 201 202 203def check_features(features, info): 204 if features is None: 205 return 206 if not isinstance(features, list): 207 raise QAPISemError(info, "'features' must be an array") 208 features[:] = [f if isinstance(f, dict) else {'name': f} 209 for f in features] 210 for f in features: 211 source = "'features' member" 212 assert isinstance(f, dict) 213 check_keys(f, info, source, ['name'], ['if']) 214 check_name_is_str(f['name'], info, source) 215 source = "%s '%s'" % (source, f['name']) 216 check_name_lower(f['name'], info, source, permit_underscore=True) 217 check_if(f, info, source) 218 219 220def check_enum(expr, info): 221 name = expr['enum'] 222 members = expr['data'] 223 prefix = expr.get('prefix') 224 225 if not isinstance(members, list): 226 raise QAPISemError(info, "'data' must be an array") 227 if prefix is not None and not isinstance(prefix, str): 228 raise QAPISemError(info, "'prefix' must be a string") 229 230 permit_upper = name in info.pragma.member_name_exceptions 231 232 members[:] = [m if isinstance(m, dict) else {'name': m} 233 for m in members] 234 for member in members: 235 source = "'data' member" 236 member_name = member['name'] 237 check_keys(member, info, source, ['name'], ['if']) 238 check_name_is_str(member_name, info, source) 239 source = "%s '%s'" % (source, member_name) 240 # Enum members may start with a digit 241 if member_name[0].isdigit(): 242 member_name = 'd' + member_name # Hack: hide the digit 243 check_name_lower(member_name, info, source, 244 permit_upper, permit_underscore=True) 245 check_if(member, info, source) 246 247 248def check_struct(expr, info): 249 name = expr['struct'] 250 members = expr['data'] 251 252 check_type(members, info, "'data'", allow_dict=name) 253 check_type(expr.get('base'), info, "'base'") 254 255 256def check_union(expr, info): 257 name = expr['union'] 258 base = expr.get('base') 259 discriminator = expr.get('discriminator') 260 members = expr['data'] 261 262 if discriminator is None: # simple union 263 if base is not None: 264 raise QAPISemError(info, "'base' requires 'discriminator'") 265 else: # flat union 266 check_type(base, info, "'base'", allow_dict=name) 267 if not base: 268 raise QAPISemError(info, "'discriminator' requires 'base'") 269 check_name_is_str(discriminator, info, "'discriminator'") 270 271 for (key, value) in members.items(): 272 source = "'data' member '%s'" % key 273 if discriminator is None: 274 check_name_lower(key, info, source, permit_underscore=True) 275 # else: name is in discriminator enum, which gets checked 276 check_keys(value, info, source, ['type'], ['if']) 277 check_if(value, info, source) 278 check_type(value['type'], info, source, allow_array=not base) 279 280 281def check_alternate(expr, info): 282 members = expr['data'] 283 284 if not members: 285 raise QAPISemError(info, "'data' must not be empty") 286 for (key, value) in members.items(): 287 source = "'data' member '%s'" % key 288 check_name_lower(key, info, source, permit_underscore=True) 289 check_keys(value, info, source, ['type'], ['if']) 290 check_if(value, info, source) 291 check_type(value['type'], info, source) 292 293 294def check_command(expr, info): 295 args = expr.get('data') 296 rets = expr.get('returns') 297 boxed = expr.get('boxed', False) 298 299 if boxed and args is None: 300 raise QAPISemError(info, "'boxed': true requires 'data'") 301 check_type(args, info, "'data'", allow_dict=not boxed) 302 check_type(rets, info, "'returns'", allow_array=True) 303 304 305def check_event(expr, info): 306 args = expr.get('data') 307 boxed = expr.get('boxed', False) 308 309 if boxed and args is None: 310 raise QAPISemError(info, "'boxed': true requires 'data'") 311 check_type(args, info, "'data'", allow_dict=not boxed) 312 313 314def check_exprs(exprs): 315 for expr_elem in exprs: 316 expr = expr_elem['expr'] 317 info = expr_elem['info'] 318 doc = expr_elem.get('doc') 319 320 if 'include' in expr: 321 continue 322 323 if 'enum' in expr: 324 meta = 'enum' 325 elif 'union' in expr: 326 meta = 'union' 327 elif 'alternate' in expr: 328 meta = 'alternate' 329 elif 'struct' in expr: 330 meta = 'struct' 331 elif 'command' in expr: 332 meta = 'command' 333 elif 'event' in expr: 334 meta = 'event' 335 else: 336 raise QAPISemError(info, "expression is missing metatype") 337 338 name = expr[meta] 339 check_name_is_str(name, info, "'%s'" % meta) 340 info.set_defn(meta, name) 341 check_defn_name_str(name, info, meta) 342 343 if doc: 344 if doc.symbol != name: 345 raise QAPISemError( 346 info, "documentation comment is for '%s'" % doc.symbol) 347 doc.check_expr(expr) 348 elif info.pragma.doc_required: 349 raise QAPISemError(info, 350 "documentation comment required") 351 352 if meta == 'enum': 353 check_keys(expr, info, meta, 354 ['enum', 'data'], ['if', 'features', 'prefix']) 355 check_enum(expr, info) 356 elif meta == 'union': 357 check_keys(expr, info, meta, 358 ['union', 'data'], 359 ['base', 'discriminator', 'if', 'features']) 360 normalize_members(expr.get('base')) 361 normalize_members(expr['data']) 362 check_union(expr, info) 363 elif meta == 'alternate': 364 check_keys(expr, info, meta, 365 ['alternate', 'data'], ['if', 'features']) 366 normalize_members(expr['data']) 367 check_alternate(expr, info) 368 elif meta == 'struct': 369 check_keys(expr, info, meta, 370 ['struct', 'data'], ['base', 'if', 'features']) 371 normalize_members(expr['data']) 372 check_struct(expr, info) 373 elif meta == 'command': 374 check_keys(expr, info, meta, 375 ['command'], 376 ['data', 'returns', 'boxed', 'if', 'features', 377 'gen', 'success-response', 'allow-oob', 378 'allow-preconfig', 'coroutine']) 379 normalize_members(expr.get('data')) 380 check_command(expr, info) 381 elif meta == 'event': 382 check_keys(expr, info, meta, 383 ['event'], ['data', 'boxed', 'if', 'features']) 384 normalize_members(expr.get('data')) 385 check_event(expr, info) 386 else: 387 assert False, 'unexpected meta type' 388 389 check_if(expr, info, meta) 390 check_features(expr.get('features'), info) 391 check_flags(expr, info) 392 393 return exprs 394