barectf/config.py

   1 # The MIT License (MIT)
   2 #
   3 # Copyright (c) 2015-2016 Philippe Proulx <pproulx@efficios.com>
   4 #
   5 # Permission is hereby granted, free of charge, to any person obtaining a copy
   6 # of this software and associated documentation files (the "Software"), to deal
   7 # in the Software without restriction, including without limitation the rights
   8 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   9 # copies of the Software, and to permit persons to whom the Software is
  10 # furnished to do so, subject to the following conditions:
  11 #
  12 # The above copyright notice and this permission notice shall be included in
  13 # all copies or substantial portions of the Software.
  14 #
  15 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  21 # THE SOFTWARE.
  22
  23 from barectf import metadata
  24 import collections
  25 import datetime
  26 import barectf
  27 import enum
  28 import yaml
  29 import uuid
  30 import copy
  31 import re
  32 import os
  33
  34
  35 class ConfigError(RuntimeError):
  36     def __init__(self, msg, prev=None):
  37         super().__init__(msg)
  38         self._prev = prev
  39
  40     @property
  41     def prev(self):
  42         return self._prev
  43
  44
  45 class Config:
  46     def __init__(self, version, prefix, metadata):
  47         self.prefix = prefix
  48         self.version = version
  49         self.metadata = metadata
  50
  51     def _validate_metadata(self, meta):
  52         try:
  53             validator = _MetadataTypesHistologyValidator()
  54             validator.validate(meta)
  55             validator = _MetadataDynamicTypesValidator()
  56             validator.validate(meta)
  57             validator = _MetadataSpecialFieldsValidator()
  58             validator.validate(meta)
  59         except Exception as e:
  60             raise ConfigError('metadata error', e)
  61
  62         try:
  63             validator = _BarectfMetadataValidator()
  64             validator.validate(meta)
  65         except Exception as e:
  66             raise ConfigError('barectf metadata error', e)
  67
  68     def _augment_metadata_env(self, meta):
  69         env = meta.env
  70
  71         env['domain'] = 'bare'
  72         env['tracer_name'] = 'barectf'
  73         version_tuple = barectf.get_version_tuple()
  74         env['tracer_major'] = version_tuple[0]
  75         env['tracer_minor'] = version_tuple[1]
  76         env['tracer_patch'] = version_tuple[2]
  77         env['barectf_gen_date'] = str(datetime.datetime.now().isoformat())
  78
  79     @property
  80     def version(self):
  81         return self._version
  82
  83     @version.setter
  84     def version(self, value):
  85         self._version = value
  86
  87     @property
  88     def metadata(self):
  89         return self._metadata
  90
  91     @metadata.setter
  92     def metadata(self, value):
  93         self._validate_metadata(value)
  94         self._augment_metadata_env(value)
  95         self._metadata = value
  96
  97     @property
  98     def prefix(self):
  99         return self._prefix
 100
 101     @prefix.setter
 102     def prefix(self, value):
 103         if not is_valid_identifier(value):
 104             raise ConfigError('prefix must be a valid C identifier')
 105
 106         self._prefix = value
 107
 108
 109 def _is_assoc_array_prop(node):
 110     return isinstance(node, dict)
 111
 112
 113 def _is_array_prop(node):
 114     return isinstance(node, list)
 115
 116
 117 def _is_int_prop(node):
 118     return type(node) is int
 119
 120
 121 def _is_str_prop(node):
 122     return type(node) is str
 123
 124
 125 def _is_bool_prop(node):
 126     return type(node) is bool
 127
 128
 129 def _is_valid_alignment(align):
 130     return ((align & (align - 1)) == 0) and align > 0
 131
 132
 133 def _byte_order_str_to_bo(bo_str):
 134     bo_str = bo_str.lower()
 135
 136     if bo_str == 'le':
 137         return metadata.ByteOrder.LE
 138     elif bo_str == 'be':
 139         return metadata.ByteOrder.BE
 140
 141
 142 def _encoding_str_to_encoding(encoding_str):
 143     encoding_str = encoding_str.lower()
 144
 145     if encoding_str == 'utf-8' or encoding_str == 'utf8':
 146         return metadata.Encoding.UTF8
 147     elif encoding_str == 'ascii':
 148         return metadata.Encoding.ASCII
 149     elif encoding_str == 'none':
 150         return metadata.Encoding.NONE
 151
 152
 153 _re_iden = re.compile(r'^[a-zA-Z][a-zA-Z0-9_]*$')
 154 _ctf_keywords = set([
 155     'align',
 156     'callsite',
 157     'clock',
 158     'enum',
 159     'env',
 160     'event',
 161     'floating_point',
 162     'integer',
 163     'stream',
 164     'string',
 165     'struct',
 166     'trace',
 167     'typealias',
 168     'typedef',
 169     'variant',
 170 ])
 171
 172
 173 def is_valid_identifier(iden):
 174     if not _re_iden.match(iden):
 175         return False
 176
 177     if _re_iden in _ctf_keywords:
 178         return False
 179
 180     return True
 181
 182
 183 def _get_first_unknown_prop(node, known_props):
 184     for prop_name in node:
 185         if prop_name in known_props:
 186             continue
 187
 188         return prop_name
 189
 190
 191 # This validator validates the configured metadata for barectf specific
 192 # needs.
 193 #
 194 # barectf needs:
 195 #
 196 #   * all header/contexts are at least byte-aligned
 197 #   * all integer and floating point number sizes to be <= 64
 198 #   * no inner structures, arrays, or variants
 199 class _BarectfMetadataValidator:
 200     def __init__(self):
 201         self._type_to_validate_type_func = {
 202             metadata.Integer: self._validate_int_type,
 203             metadata.FloatingPoint: self._validate_float_type,
 204             metadata.Enum: self._validate_enum_type,
 205             metadata.String: self._validate_string_type,
 206             metadata.Struct: self._validate_struct_type,
 207             metadata.Array: self._validate_array_type,
 208             metadata.Variant: self._validate_variant_type,
 209         }
 210
 211     def _validate_int_type(self, t, entity_root):
 212         if t.size > 64:
 213             raise ConfigError('integer type\'s size must be lesser than or equal to 64 bits')
 214
 215     def _validate_float_type(self, t, entity_root):
 216         if t.size > 64:
 217             raise ConfigError('floating point number type\'s size must be lesser than or equal to 64 bits')
 218
 219     def _validate_enum_type(self, t, entity_root):
 220         if t.value_type.size > 64:
 221             raise ConfigError('enumeration type\'s integer type\'s size must be lesser than or equal to 64 bits')
 222
 223     def _validate_string_type(self, t, entity_root):
 224         pass
 225
 226     def _validate_struct_type(self, t, entity_root):
 227         if not entity_root:
 228             raise ConfigError('inner structure types are not supported as of this version')
 229
 230         for field_name, field_type in t.fields.items():
 231             if entity_root and self._cur_entity is _Entity.TRACE_PACKET_HEADER:
 232                 if field_name == 'uuid':
 233                     # allow
 234                     continue
 235
 236             try:
 237                 self._validate_type(field_type, False)
 238             except Exception as e:
 239                 raise ConfigError('in structure type\'s field "{}"'.format(field_name), e)
 240
 241     def _validate_array_type(self, t, entity_root):
 242         raise ConfigError('array types are not supported as of this version')
 243
 244     def _validate_variant_type(self, t, entity_root):
 245         raise ConfigError('variant types are not supported as of this version')
 246
 247     def _validate_type(self, t, entity_root):
 248         self._type_to_validate_type_func[type(t)](t, entity_root)
 249
 250     def _validate_entity(self, t):
 251         if t is None:
 252             return
 253
 254         # make sure entity is byte-aligned
 255         if t.align < 8:
 256             raise ConfigError('type\'s alignment must be at least byte-aligned')
 257
 258         # make sure entity is a structure
 259         if type(t) is not metadata.Struct:
 260             raise ConfigError('expecting a structure type')
 261
 262         # validate types
 263         self._validate_type(t, True)
 264
 265     def _validate_entities_and_names(self, meta):
 266         self._cur_entity = _Entity.TRACE_PACKET_HEADER
 267
 268         try:
 269             self._validate_entity(meta.trace.packet_header_type)
 270         except Exception as e:
 271             raise ConfigError('invalid trace packet header type', e)
 272
 273         for stream_name, stream in meta.streams.items():
 274             if not is_valid_identifier(stream_name):
 275                 raise ConfigError('stream name "{}" is not a valid C identifier'.format(stream_name))
 276
 277             self._cur_entity = _Entity.STREAM_PACKET_CONTEXT
 278
 279             try:
 280                 self._validate_entity(stream.packet_context_type)
 281             except Exception as e:
 282                 raise ConfigError('invalid packet context type in stream "{}"'.format(stream_name), e)
 283
 284             self._cur_entity = _Entity.STREAM_EVENT_HEADER
 285
 286             try:
 287                 self._validate_entity(stream.event_header_type)
 288             except Exception as e:
 289                 raise ConfigError('invalid event header type in stream "{}"'.format(stream_name), e)
 290
 291             self._cur_entity = _Entity.STREAM_EVENT_CONTEXT
 292
 293             try:
 294                 self._validate_entity(stream.event_context_type)
 295             except Exception as e:
 296                 raise ConfigError('invalid event context type in stream "{}"'.format(stream_name), e)
 297
 298             try:
 299                 for ev_name, ev in stream.events.items():
 300                     if not is_valid_identifier(ev_name):
 301                         raise ConfigError('event name "{}" is not a valid C identifier'.format(ev_name))
 302
 303                     self._cur_entity = _Entity.EVENT_CONTEXT
 304
 305                     try:
 306                         self._validate_entity(ev.context_type)
 307                     except Exception as e:
 308                         raise ConfigError('invalid context type in event "{}"'.format(ev_name), e)
 309
 310                     self._cur_entity = _Entity.EVENT_PAYLOAD
 311
 312                     if ev.payload_type is None:
 313                         raise ConfigError('missing payload type in event "{}"'.format(ev_name), e)
 314
 315                     try:
 316                         self._validate_entity(ev.payload_type)
 317                     except Exception as e:
 318                         raise ConfigError('invalid payload type in event "{}"'.format(ev_name), e)
 319
 320                     if not ev.payload_type.fields:
 321                         raise ConfigError('empty payload type in event "{}"'.format(ev_name), e)
 322             except Exception as e:
 323                 raise ConfigError('invalid stream "{}"'.format(stream_name), e)
 324
 325     def validate(self, meta):
 326         self._validate_entities_and_names(meta)
 327
 328
 329 # This validator validates special fields of trace, stream, and event
 330 # types. For example, if checks that the "stream_id" field exists in the
 331 # trace packet header if there's more than one stream, and much more.
 332 class _MetadataSpecialFieldsValidator:
 333     def _validate_trace_packet_header_type(self, t):
 334         # needs "stream_id" field?
 335         if len(self._meta.streams) > 1:
 336             # yes
 337             if t is None:
 338                 raise ConfigError('need "stream_id" field in trace packet header type, but trace packet header type is missing')
 339
 340             if type(t) is not metadata.Struct:
 341                 raise ConfigError('need "stream_id" field in trace packet header type, but trace packet header type is not a structure type')
 342
 343             if 'stream_id' not in t.fields:
 344                 raise ConfigError('need "stream_id" field in trace packet header type')
 345
 346         # validate "magic" and "stream_id" types
 347         if type(t) is not metadata.Struct:
 348             return
 349
 350         for i, (field_name, field_type) in enumerate(t.fields.items()):
 351             if field_name == 'magic':
 352                 if type(field_type) is not metadata.Integer:
 353                     raise ConfigError('"magic" field in trace packet header type must be an integer type')
 354
 355                 if field_type.signed or field_type.size != 32:
 356                     raise ConfigError('"magic" field in trace packet header type must be a 32-bit unsigned integer type')
 357
 358                 if i != 0:
 359                     raise ConfigError('"magic" field must be the first trace packet header type\'s field')
 360             elif field_name == 'stream_id':
 361                 if type(field_type) is not metadata.Integer:
 362                     raise ConfigError('"stream_id" field in trace packet header type must be an integer type')
 363
 364                 if field_type.signed:
 365                     raise ConfigError('"stream_id" field in trace packet header type must be an unsigned integer type')
 366
 367                 # "id" size can fit all event IDs
 368                 if len(self._meta.streams) > (1 << field_type.size):
 369                     raise ConfigError('"stream_id" field\' size in trace packet header type is too small for the number of trace streams')
 370             elif field_name == 'uuid':
 371                 if self._meta.trace.uuid is None:
 372                     raise ConfigError('"uuid" field in trace packet header type specified, but no trace UUID provided')
 373
 374                 if type(field_type) is not metadata.Array:
 375                     raise ConfigError('"uuid" field in trace packet header type must be an array')
 376
 377                 if field_type.length != 16:
 378                     raise ConfigError('"uuid" field in trace packet header type must be an array of 16 bytes')
 379
 380                 element_type = field_type.element_type
 381
 382                 if type(element_type) is not metadata.Integer:
 383                     raise ConfigError('"uuid" field in trace packet header type must be an array of 16 unsigned bytes')
 384
 385                 if element_type.size != 8:
 386                     raise ConfigError('"uuid" field in trace packet header type must be an array of 16 unsigned bytes')
 387
 388                 if element_type.signed:
 389                     raise ConfigError('"uuid" field in trace packet header type must be an array of 16 unsigned bytes')
 390
 391                 if element_type.align != 8:
 392                     raise ConfigError('"uuid" field in trace packet header type must be an array of 16 unsigned, byte-aligned bytes')
 393
 394     def _validate_trace(self, meta):
 395         self._validate_trace_packet_header_type(meta.trace.packet_header_type)
 396
 397     def _validate_stream_packet_context(self, stream):
 398         t = stream.packet_context_type
 399
 400         if type(t) is None:
 401             raise ConfigError('missing "packet-context-type" property in stream object')
 402
 403         if type(t) is not metadata.Struct:
 404             raise ConfigError('"packet-context-type": expecting a structure type')
 405
 406         # "timestamp_begin", if exists, is an unsigned integer type,
 407         # mapped to a clock
 408         ts_begin = None
 409
 410         if 'timestamp_begin' in t.fields:
 411             ts_begin = t.fields['timestamp_begin']
 412
 413             if type(ts_begin) is not metadata.Integer:
 414                 raise ConfigError('"timestamp_begin" field in stream packet context type must be an integer type')
 415
 416             if ts_begin.signed:
 417                 raise ConfigError('"timestamp_begin" field in stream packet context type must be an unsigned integer type')
 418
 419             if not ts_begin.property_mappings:
 420                 raise ConfigError('"timestamp_begin" field in stream packet context type must be mapped to a clock')
 421
 422         # "timestamp_end", if exists, is an unsigned integer type,
 423         # mapped to a clock
 424         ts_end = None
 425
 426         if 'timestamp_end' in t.fields:
 427             ts_end = t.fields['timestamp_end']
 428
 429             if type(ts_end) is not metadata.Integer:
 430                 raise ConfigError('"timestamp_end" field in stream packet context type must be an integer type')
 431
 432             if ts_end.signed:
 433                 raise ConfigError('"timestamp_end" field in stream packet context type must be an unsigned integer type')
 434
 435             if not ts_end.property_mappings:
 436                 raise ConfigError('"timestamp_end" field in stream packet context type must be mapped to a clock')
 437
 438         # "timestamp_begin" and "timestamp_end" exist together
 439         if (('timestamp_begin' in t.fields) ^ ('timestamp_end' in t.fields)):
 440             raise ConfigError('"timestamp_begin" and "timestamp_end" fields must be defined together in stream packet context type')
 441
 442         # "timestamp_begin" and "timestamp_end" are mapped to the same clock
 443         if ts_begin is not None and ts_end is not None:
 444             if ts_begin.property_mappings[0].object.name != ts_end.property_mappings[0].object.name:
 445                 raise ConfigError('"timestamp_begin" and "timestamp_end" fields must be mapped to the same clock object in stream packet context type')
 446
 447         # "events_discarded", if exists, is an unsigned integer type
 448         if 'events_discarded' in t.fields:
 449             events_discarded = t.fields['events_discarded']
 450
 451             if type(events_discarded) is not metadata.Integer:
 452                 raise ConfigError('"events_discarded" field in stream packet context type must be an integer type')
 453
 454             if events_discarded.signed:
 455                 raise ConfigError('"events_discarded" field in stream packet context type must be an unsigned integer type')
 456
 457         # "packet_size" and "content_size" must exist
 458         if 'packet_size' not in t.fields:
 459             raise ConfigError('missing "packet_size" field in stream packet context type')
 460
 461         packet_size = t.fields['packet_size']
 462
 463         # "content_size" and "content_size" must exist
 464         if 'content_size' not in t.fields:
 465             raise ConfigError('missing "content_size" field in stream packet context type')
 466
 467         content_size = t.fields['content_size']
 468
 469         # "packet_size" is an unsigned integer type
 470         if type(packet_size) is not metadata.Integer:
 471             raise ConfigError('"packet_size" field in stream packet context type must be an integer type')
 472
 473         if packet_size.signed:
 474             raise ConfigError('"packet_size" field in stream packet context type must be an unsigned integer type')
 475
 476         # "content_size" is an unsigned integer type
 477         if type(content_size) is not metadata.Integer:
 478             raise ConfigError('"content_size" field in stream packet context type must be an integer type')
 479
 480         if content_size.signed:
 481             raise ConfigError('"content_size" field in stream packet context type must be an unsigned integer type')
 482
 483         # "packet_size" size should be greater than or equal to "content_size" size
 484         if content_size.size > packet_size.size:
 485             raise ConfigError('"content_size" field size must be lesser than or equal to "packet_size" field size')
 486
 487     def _validate_stream_event_header(self, stream):
 488         t = stream.event_header_type
 489
 490         # needs "id" field?
 491         if len(stream.events) > 1:
 492             # yes
 493             if t is None:
 494                 raise ConfigError('need "id" field in stream event header type, but stream event header type is missing')
 495
 496             if type(t) is not metadata.Struct:
 497                 raise ConfigError('need "id" field in stream event header type, but stream event header type is not a structure type')
 498
 499             if 'id' not in t.fields:
 500                 raise ConfigError('need "id" field in stream event header type')
 501
 502         # validate "id" and "timestamp" types
 503         if type(t) is not metadata.Struct:
 504             return
 505
 506         # "timestamp", if exists, is an unsigned integer type,
 507         # mapped to a clock
 508         if 'timestamp' in t.fields:
 509             ts = t.fields['timestamp']
 510
 511             if type(ts) is not metadata.Integer:
 512                 raise ConfigError('"timestamp" field in stream event header type must be an integer type')
 513
 514             if ts.signed:
 515                 raise ConfigError('"timestamp" field in stream event header type must be an unsigned integer type')
 516
 517             if not ts.property_mappings:
 518                 raise ConfigError('"timestamp" field in stream event header type must be mapped to a clock')
 519
 520         if 'id' in t.fields:
 521             eid = t.fields['id']
 522
 523             # "id" is an unsigned integer type
 524             if type(eid) is not metadata.Integer:
 525                 raise ConfigError('"id" field in stream event header type must be an integer type')
 526
 527             if eid.signed:
 528                 raise ConfigError('"id" field in stream event header type must be an unsigned integer type')
 529
 530             # "id" size can fit all event IDs
 531             if len(stream.events) > (1 << eid.size):
 532                 raise ConfigError('"id" field\' size in stream event header type is too small for the number of stream events')
 533
 534     def _validate_stream(self, stream):
 535         self._validate_stream_packet_context(stream)
 536         self._validate_stream_event_header(stream)
 537
 538     def validate(self, meta):
 539         self._meta = meta
 540         self._validate_trace(meta)
 541
 542         for stream in meta.streams.values():
 543             try:
 544                 self._validate_stream(stream)
 545             except Exception as e:
 546                 raise ConfigError('invalid stream "{}"'.format(stream.name), e)
 547
 548
 549 class _MetadataDynamicTypesValidatorStackEntry:
 550     def __init__(self, base_t):
 551         self._base_t = base_t
 552         self._index = 0
 553
 554     @property
 555     def index(self):
 556         return self._index
 557
 558     @index.setter
 559     def index(self, value):
 560         self._index = value
 561
 562     @property
 563     def base_t(self):
 564         return self._base_t
 565
 566     @base_t.setter
 567     def base_t(self, value):
 568         self._base_t = value
 569
 570
 571 # Entities. Order of values is important here.
 572 @enum.unique
 573 class _Entity(enum.IntEnum):
 574     TRACE_PACKET_HEADER = 0
 575     STREAM_PACKET_CONTEXT = 1
 576     STREAM_EVENT_HEADER = 2
 577     STREAM_EVENT_CONTEXT = 3
 578     EVENT_CONTEXT = 4
 579     EVENT_PAYLOAD = 5
 580
 581
 582 # This validator validates dynamic metadata types, that is, it ensures
 583 # variable-length array lengths and variant tags actually point to
 584 # something that exists. It also checks that variable-length array
 585 # lengths point to integer types and variant tags to enumeration types.
 586 class _MetadataDynamicTypesValidator:
 587     def __init__(self):
 588         self._type_to_visit_type_func = {
 589             metadata.Integer: None,
 590             metadata.FloatingPoint: None,
 591             metadata.Enum: None,
 592             metadata.String: None,
 593             metadata.Struct: self._visit_struct_type,
 594             metadata.Array: self._visit_array_type,
 595             metadata.Variant: self._visit_variant_type,
 596         }
 597
 598         self._cur_trace = None
 599         self._cur_stream = None
 600         self._cur_event = None
 601
 602     def _lookup_path_from_base(self, path, parts, base, start_index,
 603                                base_is_current, from_t):
 604         index = start_index
 605         cur_t = base
 606         found_path = []
 607
 608         while index < len(parts):
 609             part = parts[index]
 610             next_t = None
 611
 612             if type(cur_t) is metadata.Struct:
 613                 enumerated_items = enumerate(cur_t.fields.items())
 614
 615                 # lookup each field
 616                 for i, (field_name, field_type) in enumerated_items:
 617                     if field_name == part:
 618                         next_t = field_type
 619                         found_path.append((i, field_type))
 620
 621                 if next_t is None:
 622                     raise ConfigError('invalid path "{}": cannot find field "{}" in structure type'.format(path, part))
 623             elif type(cur_t) is metadata.Variant:
 624                 enumerated_items = enumerate(cur_t.types.items())
 625
 626                 # lookup each type
 627                 for i, (type_name, type_type) in enumerated_items:
 628                     if type_name == part:
 629                         next_t = type_type
 630                         found_path.append((i, type_type))
 631
 632                 if next_t is None:
 633                     raise ConfigError('invalid path "{}": cannot find type "{}" in variant type'.format(path, part))
 634             else:
 635                 raise ConfigError('invalid path "{}": requesting "{}" in a non-variant, non-structure type'.format(path, part))
 636
 637             cur_t = next_t
 638             index += 1
 639
 640         # make sure that the pointed type is not the pointing type
 641         if from_t is cur_t:
 642             raise ConfigError('invalid path "{}": pointing to self'.format(path))
 643
 644         # if we're here, we found the type; however, it could be located
 645         # _after_ the variant/VLA looking for it, if the pointing
 646         # and pointed types are in the same entity, so compare the
 647         # current stack entries indexes to our index path in that case
 648         if not base_is_current:
 649             return cur_t
 650
 651         for index, entry in enumerate(self._stack):
 652             if index == len(found_path):
 653                 # end of index path; valid so far
 654                 break
 655
 656             if found_path[index][0] > entry.index:
 657                 raise ConfigError('invalid path "{}": pointed type is after pointing type'.format(path))
 658
 659         # also make sure that both pointed and pointing types share
 660         # a common structure ancestor
 661         for index, entry in enumerate(self._stack):
 662             if index == len(found_path):
 663                 break
 664
 665             if entry.base_t is not found_path[index][1]:
 666                 # found common ancestor
 667                 if type(entry.base_t) is metadata.Variant:
 668                     raise ConfigError('invalid path "{}": type cannot be reached because pointed and pointing types are in the same variant type'.format(path))
 669
 670         return cur_t
 671
 672     def _lookup_path_from_top(self, path, parts):
 673         if len(parts) != 1:
 674             raise ConfigError('invalid path "{}": multipart relative path not supported'.format(path))
 675
 676         find_name = parts[0]
 677         index = len(self._stack) - 1
 678         got_struct = False
 679
 680         # check stack entries in reversed order
 681         for entry in reversed(self._stack):
 682             # structure base type
 683             if type(entry.base_t) is metadata.Struct:
 684                 got_struct = True
 685                 enumerated_items = enumerate(entry.base_t.fields.items())
 686
 687                 # lookup each field, until the current visiting index is met
 688                 for i, (field_name, field_type) in enumerated_items:
 689                     if i == entry.index:
 690                         break
 691
 692                     if field_name == find_name:
 693                         return field_type
 694
 695             # variant base type
 696             elif type(entry.base_t) is metadata.Variant:
 697                 enumerated_items = enumerate(entry.base_t.types.items())
 698
 699                 # lookup each type, until the current visiting index is met
 700                 for i, (type_name, type_type) in enumerated_items:
 701                     if i == entry.index:
 702                         break
 703
 704                     if type_name == find_name:
 705                         if not got_struct:
 706                             raise ConfigError('invalid path "{}": type cannot be reached because pointed and pointing types are in the same variant type'.format(path))
 707
 708                         return type_type
 709
 710         # nothing returned here: cannot find type
 711         raise ConfigError('invalid path "{}": cannot find type in current context'.format(path))
 712
 713     def _lookup_path(self, path, from_t):
 714         parts = path.lower().split('.')
 715         base = None
 716         base_is_current = False
 717
 718         if len(parts) >= 3:
 719             if parts[0] == 'trace':
 720                 if parts[1] == 'packet' and parts[2] == 'header':
 721                     # make sure packet header exists
 722                     if self._cur_trace.packet_header_type is None:
 723                         raise ConfigError('invalid path "{}": no defined trace packet header type'.format(path))
 724
 725                     base = self._cur_trace.packet_header_type
 726
 727                     if self._cur_entity == _Entity.TRACE_PACKET_HEADER:
 728                         base_is_current = True
 729                 else:
 730                     raise ConfigError('invalid path "{}": unknown names after "trace"'.format(path))
 731             elif parts[0] == 'stream':
 732                 if parts[1] == 'packet' and parts[2] == 'context':
 733                     if self._cur_entity < _Entity.STREAM_PACKET_CONTEXT:
 734                         raise ConfigError('invalid path "{}": cannot access stream packet context here'.format(path))
 735
 736                     if self._cur_stream.packet_context_type is None:
 737                         raise ConfigError('invalid path "{}": no defined stream packet context type'.format(path))
 738
 739                     base = self._cur_stream.packet_context_type
 740
 741                     if self._cur_entity == _Entity.STREAM_PACKET_CONTEXT:
 742                         base_is_current = True
 743                 elif parts[1] == 'event':
 744                     if parts[2] == 'header':
 745                         if self._cur_entity < _Entity.STREAM_EVENT_HEADER:
 746                             raise ConfigError('invalid path "{}": cannot access stream event header here'.format(path))
 747
 748                         if self._cur_stream.event_header_type is None:
 749                             raise ConfigError('invalid path "{}": no defined stream event header type'.format(path))
 750
 751                         base = self._cur_stream.event_header_type
 752
 753                         if self._cur_entity == _Entity.STREAM_EVENT_HEADER:
 754                             base_is_current = True
 755                     elif parts[2] == 'context':
 756                         if self._cur_entity < _Entity.STREAM_EVENT_CONTEXT:
 757                             raise ConfigError('invalid path "{}": cannot access stream event context here'.format(path))
 758
 759                         if self._cur_stream.event_context_type is None:
 760                             raise ConfigError('invalid path "{}": no defined stream event context type'.format(path))
 761
 762                         base = self._cur_stream.event_context_type
 763
 764                         if self._cur_entity == _Entity.STREAM_EVENT_CONTEXT:
 765                             base_is_current = True
 766                     else:
 767                         raise ConfigError('invalid path "{}": unknown names after "stream.event"'.format(path))
 768                 else:
 769                     raise ConfigError('invalid path "{}": unknown names after "stream"'.format(path))
 770
 771             if base is not None:
 772                 start_index = 3
 773
 774         if len(parts) >= 2 and base is None:
 775             if parts[0] == 'event':
 776                 if parts[1] == 'context':
 777                     if self._cur_entity < _Entity.EVENT_CONTEXT:
 778                         raise ConfigError('invalid path "{}": cannot access event context here'.format(path))
 779
 780                     if self._cur_event.context_type is None:
 781                         raise ConfigError('invalid path "{}": no defined event context type'.format(path))
 782
 783                     base = self._cur_event.context_type
 784
 785                     if self._cur_entity == _Entity.EVENT_CONTEXT:
 786                         base_is_current = True
 787                 elif parts[1] == 'payload' or parts[1] == 'fields':
 788                     if self._cur_entity < _Entity.EVENT_PAYLOAD:
 789                         raise ConfigError('invalid path "{}": cannot access event payload here'.format(path))
 790
 791                     if self._cur_event.payload_type is None:
 792                         raise ConfigError('invalid path "{}": no defined event payload type'.format(path))
 793
 794                     base = self._cur_event.payload_type
 795
 796                     if self._cur_entity == _Entity.EVENT_PAYLOAD:
 797                         base_is_current = True
 798                 else:
 799                     raise ConfigError('invalid path "{}": unknown names after "event"'.format(path))
 800
 801             if base is not None:
 802                 start_index = 2
 803
 804         if base is not None:
 805             return self._lookup_path_from_base(path, parts, base, start_index,
 806                                                base_is_current, from_t)
 807         else:
 808             return self._lookup_path_from_top(path, parts)
 809
 810     def _stack_reset(self):
 811         self._stack = []
 812
 813     def _stack_push(self, base_t):
 814         entry = _MetadataDynamicTypesValidatorStackEntry(base_t)
 815         self._stack.append(entry)
 816
 817     def _stack_pop(self):
 818         self._stack.pop()
 819
 820     def _stack_incr_index(self):
 821         self._stack[-1].index += 1
 822
 823     def _visit_struct_type(self, t):
 824         self._stack_push(t)
 825
 826         for field_name, field_type in t.fields.items():
 827             try:
 828                 self._visit_type(field_type)
 829             except Exception as e:
 830                 raise ConfigError('in structure type\'s field "{}"'.format(field_name), e)
 831
 832             self._stack_incr_index()
 833
 834         self._stack_pop()
 835
 836     def _visit_array_type(self, t):
 837         if t.is_variable_length:
 838             # find length type
 839             try:
 840                 length_type = self._lookup_path(t.length, t)
 841             except Exception as e:
 842                 raise ConfigError('invalid array type\'s length', e)
 843
 844             # make sure length type an unsigned integer
 845             if type(length_type) is not metadata.Integer:
 846                 raise ConfigError('array type\'s length does not point to an integer type')
 847
 848             if length_type.signed:
 849                 raise ConfigError('array type\'s length does not point to an unsigned integer type')
 850
 851         self._visit_type(t.element_type)
 852
 853     def _visit_variant_type(self, t):
 854         # find tag type
 855         try:
 856             tag_type = self._lookup_path(t.tag, t)
 857         except Exception as e:
 858             raise ConfigError('invalid variant type\'s tag', e)
 859
 860         # make sure tag type is an enumeration
 861         if type(tag_type) is not metadata.Enum:
 862             raise ConfigError('variant type\'s tag does not point to an enumeration type')
 863
 864         # verify that each variant type's type exists as an enumeration member
 865         for tag_name in t.types.keys():
 866             if tag_name not in tag_type.members:
 867                 raise ConfigError('cannot find variant type\'s type "{}" in pointed tag type'.format(tag_name))
 868
 869         self._stack_push(t)
 870
 871         for type_name, type_type in t.types.items():
 872             try:
 873                 self._visit_type(type_type)
 874             except Exception as e:
 875                 raise ConfigError('in variant type\'s type "{}"'.format(type_name), e)
 876
 877             self._stack_incr_index()
 878
 879         self._stack_pop()
 880
 881     def _visit_type(self, t):
 882         if t is None:
 883             return
 884
 885         if type(t) in self._type_to_visit_type_func:
 886             func = self._type_to_visit_type_func[type(t)]
 887
 888             if func is not None:
 889                 func(t)
 890
 891     def _visit_event(self, ev):
 892         ev_name = ev.name
 893
 894         # set current event
 895         self._cur_event = ev
 896
 897         # visit event context type
 898         self._stack_reset()
 899         self._cur_entity = _Entity.EVENT_CONTEXT
 900
 901         try:
 902             self._visit_type(ev.context_type)
 903         except Exception as e:
 904             raise ConfigError('invalid context type in event "{}"'.format(ev_name), e)
 905
 906         # visit event payload type
 907         self._stack_reset()
 908         self._cur_entity = _Entity.EVENT_PAYLOAD
 909
 910         try:
 911             self._visit_type(ev.payload_type)
 912         except Exception as e:
 913             raise ConfigError('invalid payload type in event "{}"'.format(ev_name), e)
 914
 915     def _visit_stream(self, stream):
 916         stream_name = stream.name
 917
 918         # set current stream
 919         self._cur_stream = stream
 920
 921         # reset current event
 922         self._cur_event = None
 923
 924         # visit stream packet context type
 925         self._stack_reset()
 926         self._cur_entity = _Entity.STREAM_PACKET_CONTEXT
 927
 928         try:
 929             self._visit_type(stream.packet_context_type)
 930         except Exception as e:
 931             raise ConfigError('invalid packet context type in stream "{}"'.format(stream_name), e)
 932
 933         # visit stream event header type
 934         self._stack_reset()
 935         self._cur_entity = _Entity.STREAM_EVENT_HEADER
 936
 937         try:
 938             self._visit_type(stream.event_header_type)
 939         except Exception as e:
 940             raise ConfigError('invalid event header type in stream "{}"'.format(stream_name), e)
 941
 942         # visit stream event context type
 943         self._stack_reset()
 944         self._cur_entity = _Entity.STREAM_EVENT_CONTEXT
 945
 946         try:
 947             self._visit_type(stream.event_context_type)
 948         except Exception as e:
 949             raise ConfigError('invalid event context type in stream "{}"'.format(stream_name), e)
 950
 951         # visit events
 952         for ev in stream.events.values():
 953             try:
 954                 self._visit_event(ev)
 955             except Exception as e:
 956                 raise ConfigError('invalid stream "{}"'.format(stream_name))
 957
 958     def validate(self, meta):
 959         # set current trace
 960         self._cur_trace = meta.trace
 961
 962         # visit trace packet header type
 963         self._stack_reset()
 964         self._cur_entity = _Entity.TRACE_PACKET_HEADER
 965
 966         try:
 967             self._visit_type(meta.trace.packet_header_type)
 968         except Exception as e:
 969             raise ConfigError('invalid packet header type in trace', e)
 970
 971         # visit streams
 972         for stream in meta.streams.values():
 973             self._visit_stream(stream)
 974
 975
 976 # Since type inheritance allows types to be only partially defined at
 977 # any place in the configuration, this validator validates that actual
 978 # trace, stream, and event types are all complete and valid. Therefore
 979 # an invalid, but unusued type alias is accepted.
 980 class _MetadataTypesHistologyValidator:
 981     def __init__(self):
 982         self._type_to_validate_type_histology_func = {
 983             metadata.Integer: self._validate_integer_histology,
 984             metadata.FloatingPoint: self._validate_float_histology,
 985             metadata.Enum: self._validate_enum_histology,
 986             metadata.String: self._validate_string_histology,
 987             metadata.Struct: self._validate_struct_histology,
 988             metadata.Array: self._validate_array_histology,
 989             metadata.Variant: self._validate_variant_histology,
 990         }
 991
 992     def _validate_integer_histology(self, t):
 993         # size is set
 994         if t.size is None:
 995             raise ConfigError('missing integer type\'s size')
 996
 997     def _validate_float_histology(self, t):
 998         # exponent digits is set
 999         if t.exp_size is None:
1000             raise ConfigError('missing floating point number type\'s exponent size')
1001
1002         # mantissa digits is set
1003         if t.mant_size is None:
1004             raise ConfigError('missing floating point number type\'s mantissa size')
1005
1006         # exponent and mantissa sum is a multiple of 8
1007         if (t.exp_size + t.mant_size) % 8 != 0:
1008             raise ConfigError('floating point number type\'s mantissa and exponent sizes sum must be a multiple of 8')
1009
1010     def _validate_enum_histology(self, t):
1011         # integer type is set
1012         if t.value_type is None:
1013             raise ConfigError('missing enumeration type\'s value type')
1014
1015         # there's at least one member
1016         if not t.members:
1017             raise ConfigError('enumeration type needs at least one member')
1018
1019         # no overlapping values and all values are valid considering
1020         # the value type
1021         ranges = []
1022
1023         if t.value_type.signed:
1024             value_min = -(1 << t.value_type.size - 1)
1025             value_max = (1 << (t.value_type.size - 1)) - 1
1026         else:
1027             value_min = 0
1028             value_max = (1 << t.value_type.size) - 1
1029
1030         for label, value in t.members.items():
1031             for rg in ranges:
1032                 if value[0] <= rg[1] and rg[0] <= value[1]:
1033                     raise ConfigError('enumeration type\'s member "{}" overlaps another member'.format(label))
1034
1035             fmt = 'enumeration type\'s member "{}": value {} is outside the value type range [{}, {}]'
1036
1037             if value[0] < value_min or value[0] > value_max:
1038                 raise ConfigError(fmt.format(label, value[0], value_min, value_max))
1039
1040             if value[1] < value_min or value[1] > value_max:
1041                 raise ConfigError(fmt.format(label, value[1], value_min, value_max))
1042
1043             ranges.append(value)
1044
1045     def _validate_string_histology(self, t):
1046         # always valid
1047         pass
1048
1049     def _validate_struct_histology(self, t):
1050         # all fields are valid
1051         for field_name, field_type in t.fields.items():
1052             try:
1053                 self._validate_type_histology(field_type)
1054             except Exception as e:
1055                 raise ConfigError('invalid structure type\'s field "{}"'.format(field_name), e)
1056
1057     def _validate_array_histology(self, t):
1058         # length is set
1059         if t.length is None:
1060             raise ConfigError('missing array type\'s length')
1061
1062         # element type is set
1063         if t.element_type is None:
1064             raise ConfigError('missing array type\'s element type')
1065
1066         # element type is valid
1067         try:
1068             self._validate_type_histology(t.element_type)
1069         except Exception as e:
1070             raise ConfigError('invalid array type\'s element type', e)
1071
1072     def _validate_variant_histology(self, t):
1073         # tag is set
1074         if t.tag is None:
1075             raise ConfigError('missing variant type\'s tag')
1076
1077         # there's at least one type
1078         if not t.types:
1079             raise ConfigError('variant type needs at least one type')
1080
1081         # all types are valid
1082         for type_name, type_t in t.types.items():
1083             try:
1084                 self._validate_type_histology(type_t)
1085             except Exception as e:
1086                 raise ConfigError('invalid variant type\'s type "{}"'.format(type_name), e)
1087
1088     def _validate_type_histology(self, t):
1089         if t is None:
1090             return
1091
1092         self._type_to_validate_type_histology_func[type(t)](t)
1093
1094     def _validate_entity_type_histology(self, t):
1095         if t is None:
1096             return
1097
1098         if type(t) is not metadata.Struct:
1099             raise ConfigError('expecting a structure type')
1100
1101         self._validate_type_histology(t)
1102
1103     def _validate_event_types_histology(self, ev):
1104         ev_name = ev.name
1105
1106         # validate event context type
1107         try:
1108             self._validate_entity_type_histology(ev.context_type)
1109         except Exception as e:
1110             raise ConfigError('invalid event context type for event "{}"'.format(ev_name), e)
1111
1112         # validate event payload type
1113         if ev.payload_type is None:
1114             raise ConfigError('event payload type must exist in event "{}"'.format(ev_name))
1115
1116         # TODO: also check arrays, sequences, and variants
1117         if type(ev.payload_type) is metadata.Struct:
1118             if not ev.payload_type.fields:
1119                 raise ConfigError('event payload type must have at least one field for event "{}"'.format(ev_name))
1120
1121         try:
1122             self._validate_entity_type_histology(ev.payload_type)
1123         except Exception as e:
1124             raise ConfigError('invalid event payload type for event "{}"'.format(ev_name), e)
1125
1126     def _validate_stream_types_histology(self, stream):
1127         stream_name = stream.name
1128
1129         # validate stream packet context type
1130         try:
1131             self._validate_entity_type_histology(stream.packet_context_type)
1132         except Exception as e:
1133             raise ConfigError('invalid stream packet context type for stream "{}"'.format(stream_name), e)
1134
1135         # validate stream event header type
1136         try:
1137             self._validate_entity_type_histology(stream.event_header_type)
1138         except Exception as e:
1139             raise ConfigError('invalid stream event header type for stream "{}"'.format(stream_name), e)
1140
1141         # validate stream event context type
1142         try:
1143             self._validate_entity_type_histology(stream.event_context_type)
1144         except Exception as e:
1145             raise ConfigError('invalid stream event context type for stream "{}"'.format(stream_name), e)
1146
1147         # validate events
1148         for ev in stream.events.values():
1149             try:
1150                 self._validate_event_types_histology(ev)
1151             except Exception as e:
1152                 raise ConfigError('invalid event in stream "{}"'.format(stream_name), e)
1153
1154     def validate(self, meta):
1155         # validate trace packet header type
1156         try:
1157             self._validate_entity_type_histology(meta.trace.packet_header_type)
1158         except Exception as e:
1159             raise ConfigError('invalid trace packet header type', e)
1160
1161         # validate streams
1162         for stream in meta.streams.values():
1163             self._validate_stream_types_histology(stream)
1164
1165
1166 class _YamlConfigParser:
1167     def __init__(self, include_dirs, ignore_include_not_found, dump_config):
1168         self._class_name_to_create_type_func = {
1169             'int': self._create_integer,
1170             'integer': self._create_integer,
1171             'flt': self._create_float,
1172             'float': self._create_float,
1173             'floating-point': self._create_float,
1174             'enum': self._create_enum,
1175             'enumeration': self._create_enum,
1176             'str': self._create_string,
1177             'string': self._create_string,
1178             'struct': self._create_struct,
1179             'structure': self._create_struct,
1180             'array': self._create_array,
1181             'var': self._create_variant,
1182             'variant': self._create_variant,
1183         }
1184         self._type_to_create_type_func = {
1185             metadata.Integer: self._create_integer,
1186             metadata.FloatingPoint: self._create_float,
1187             metadata.Enum: self._create_enum,
1188             metadata.String: self._create_string,
1189             metadata.Struct: self._create_struct,
1190             metadata.Array: self._create_array,
1191             metadata.Variant: self._create_variant,
1192         }
1193         self._include_dirs = include_dirs
1194         self._ignore_include_not_found = ignore_include_not_found
1195         self._dump_config = dump_config
1196
1197     def _set_byte_order(self, metadata_node):
1198         if 'trace' not in metadata_node:
1199             raise ConfigError('missing "trace" property (metadata)')
1200
1201         trace_node = metadata_node['trace']
1202
1203         if not _is_assoc_array_prop(trace_node):
1204             raise ConfigError('"trace" property (metadata) must be an associative array')
1205
1206         if 'byte-order' not in trace_node:
1207             raise ConfigError('missing "byte-order" property (trace)')
1208
1209         bo_node = trace_node['byte-order']
1210
1211         if not _is_str_prop(bo_node):
1212             raise ConfigError('"byte-order" property of trace object must be a string ("le" or "be")')
1213
1214         self._bo = _byte_order_str_to_bo(bo_node)
1215
1216         if self._bo is None:
1217             raise ConfigError('invalid "byte-order" property (trace): must be "le" or "be"')
1218
1219     def _lookup_type_alias(self, name):
1220         if name in self._tas:
1221             return copy.deepcopy(self._tas[name])
1222
1223     def _set_int_clock_prop_mapping(self, int_obj, prop_mapping_node):
1224         unk_prop = _get_first_unknown_prop(prop_mapping_node, ['type', 'name', 'property'])
1225
1226         if unk_prop:
1227             raise ConfigError('unknown property in integer type object\'s clock property mapping: "{}"'.format(unk_prop))
1228
1229         if 'name' not in prop_mapping_node:
1230             raise ConfigError('missing "name" property in integer type object\'s clock property mapping')
1231
1232         if 'property' not in prop_mapping_node:
1233             raise ConfigError('missing "property" property in integer type object\'s clock property mapping')
1234
1235         clock_name = prop_mapping_node['name']
1236         prop = prop_mapping_node['property']
1237
1238         if not _is_str_prop(clock_name):
1239             raise ConfigError('"name" property of integer type object\'s clock property mapping must be a string')
1240
1241         if not _is_str_prop(prop):
1242             raise ConfigError('"property" property of integer type object\'s clock property mapping must be a string')
1243
1244         if clock_name not in self._clocks:
1245             raise ConfigError('invalid clock name "{}" in integer type object\'s clock property mapping'.format(clock_name))
1246
1247         if prop != 'value':
1248             raise ConfigError('invalid "property" property in integer type object\'s clock property mapping: "{}"'.format(prop))
1249
1250         mapped_clock = self._clocks[clock_name]
1251         int_obj.property_mappings.append(metadata.PropertyMapping(mapped_clock, prop))
1252
1253     def _get_first_unknown_type_prop(self, type_node, known_props):
1254         kp = known_props + ['inherit', 'class']
1255
1256         if self._version >= 201:
1257             kp.append('$inherit')
1258
1259         return _get_first_unknown_prop(type_node, kp)
1260
1261     def _create_integer(self, obj, node):
1262         if obj is None:
1263             # create integer object
1264             obj = metadata.Integer()
1265
1266         unk_prop = self._get_first_unknown_type_prop(node, [
1267             'size',
1268             'align',
1269             'signed',
1270             'byte-order',
1271             'base',
1272             'encoding',
1273             'property-mappings',
1274         ])
1275
1276         if unk_prop:
1277             raise ConfigError('unknown integer type object property: "{}"'.format(unk_prop))
1278
1279         # size
1280         if 'size' in node:
1281             size = node['size']
1282
1283             if not _is_int_prop(size):
1284                 raise ConfigError('"size" property of integer type object must be an integer')
1285
1286             if size < 1:
1287                 raise ConfigError('invalid integer size: {}'.format(size))
1288
1289             obj.size = size
1290
1291         # align
1292         if 'align' in node:
1293             align = node['align']
1294
1295             if align is None:
1296                 obj.set_default_align()
1297             else:
1298                 if not _is_int_prop(align):
1299                     raise ConfigError('"align" property of integer type object must be an integer')
1300
1301                 if not _is_valid_alignment(align):
1302                     raise ConfigError('invalid alignment: {}'.format(align))
1303
1304                 obj.align = align
1305
1306         # signed
1307         if 'signed' in node:
1308             signed = node['signed']
1309
1310             if signed is None:
1311                 obj.set_default_signed()
1312             else:
1313                 if not _is_bool_prop(signed):
1314                     raise ConfigError('"signed" property of integer type object must be a boolean')
1315
1316                 obj.signed = signed
1317
1318         # byte order
1319         if 'byte-order' in node:
1320             byte_order = node['byte-order']
1321
1322             if byte_order is None:
1323                 obj.byte_order = self._bo
1324             else:
1325                 if not _is_str_prop(byte_order):
1326                     raise ConfigError('"byte-order" property of integer type object must be a string ("le" or "be")')
1327
1328                 byte_order = _byte_order_str_to_bo(byte_order)
1329
1330                 if byte_order is None:
1331                     raise ConfigError('invalid "byte-order" property in integer type object')
1332
1333                 obj.byte_order = byte_order
1334         else:
1335             obj.byte_order = self._bo
1336
1337         # base
1338         if 'base' in node:
1339             base = node['base']
1340
1341             if base is None:
1342                 obj.set_default_base()
1343             else:
1344                 if not _is_str_prop(base):
1345                     raise ConfigError('"base" property of integer type object must be a string ("bin", "oct", "dec", or "hex")')
1346
1347                 if base == 'bin':
1348                     base = 2
1349                 elif base == 'oct':
1350                     base = 8
1351                 elif base == 'dec':
1352                     base = 10
1353                 elif base == 'hex':
1354                     base = 16
1355                 else:
1356                     raise ConfigError('unknown "base" property value: "{}" ("bin", "oct", "dec", and "hex" are accepted)'.format(base))
1357
1358                 obj.base = base
1359
1360         # encoding
1361         if 'encoding' in node:
1362             encoding = node['encoding']
1363
1364             if encoding is None:
1365                 obj.set_default_encoding()
1366             else:
1367                 if not _is_str_prop(encoding):
1368                     raise ConfigError('"encoding" property of integer type object must be a string ("none", "ascii", or "utf-8")')
1369
1370                 encoding = _encoding_str_to_encoding(encoding)
1371
1372                 if encoding is None:
1373                     raise ConfigError('invalid "encoding" property in integer type object')
1374
1375                 obj.encoding = encoding
1376
1377         # property mappings
1378         if 'property-mappings' in node:
1379             prop_mappings = node['property-mappings']
1380
1381             if prop_mappings is None:
1382                 obj.set_default_property_mappings()
1383             else:
1384                 if not _is_array_prop(prop_mappings):
1385                     raise ConfigError('"property-mappings" property of integer type object must be an array')
1386
1387                 if len(prop_mappings) > 1:
1388                     raise ConfigError('length of "property-mappings" array in integer type object must be 1')
1389
1390                 for index, prop_mapping in enumerate(prop_mappings):
1391                     if not _is_assoc_array_prop(prop_mapping):
1392                         raise ConfigError('elements of "property-mappings" property of integer type object must be associative arrays')
1393
1394                     if 'type' not in prop_mapping:
1395                         raise ConfigError('missing "type" property in integer type object\'s "property-mappings" array\'s element #{}'.format(index))
1396
1397                     prop_type = prop_mapping['type']
1398
1399                     if not _is_str_prop(prop_type):
1400                         raise ConfigError('"type" property of integer type object\'s "property-mappings" array\'s element #{} must be a string'.format(index))
1401
1402                     if prop_type == 'clock':
1403                         self._set_int_clock_prop_mapping(obj, prop_mapping)
1404                     else:
1405                         raise ConfigError('unknown property mapping type "{}" in integer type object\'s "property-mappings" array\'s element #{}'.format(prop_type, index))
1406
1407         return obj
1408
1409     def _create_float(self, obj, node):
1410         if obj is None:
1411             # create floating point number object
1412             obj = metadata.FloatingPoint()
1413
1414         unk_prop = self._get_first_unknown_type_prop(node, [
1415             'size',
1416             'align',
1417             'byte-order',
1418         ])
1419
1420         if unk_prop:
1421             raise ConfigError('unknown floating point number type object property: "{}"'.format(unk_prop))
1422
1423         # size
1424         if 'size' in node:
1425             size = node['size']
1426
1427             if not _is_assoc_array_prop(size):
1428                 raise ConfigError('"size" property of floating point number type object must be an associative array')
1429
1430             unk_prop = _get_first_unknown_prop(size, ['exp', 'mant'])
1431
1432             if unk_prop:
1433                 raise ConfigError('unknown floating point number type object\'s "size" property: "{}"'.format(unk_prop))
1434
1435             if 'exp' in size:
1436                 exp = size['exp']
1437
1438                 if not _is_int_prop(exp):
1439                     raise ConfigError('"exp" property of floating point number type object\'s "size" property must be an integer')
1440
1441                 if exp < 1:
1442                     raise ConfigError('invalid floating point number exponent size: {}')
1443
1444                 obj.exp_size = exp
1445
1446             if 'mant' in size:
1447                 mant = size['mant']
1448
1449                 if not _is_int_prop(mant):
1450                     raise ConfigError('"mant" property of floating point number type object\'s "size" property must be an integer')
1451
1452                 if mant < 1:
1453                     raise ConfigError('invalid floating point number mantissa size: {}')
1454
1455                 obj.mant_size = mant
1456
1457         # align
1458         if 'align' in node:
1459             align = node['align']
1460
1461             if align is None:
1462                 obj.set_default_align()
1463             else:
1464                 if not _is_int_prop(align):
1465                     raise ConfigError('"align" property of floating point number type object must be an integer')
1466
1467                 if not _is_valid_alignment(align):
1468                     raise ConfigError('invalid alignment: {}'.format(align))
1469
1470                 obj.align = align
1471
1472         # byte order
1473         if 'byte-order' in node:
1474             byte_order = node['byte-order']
1475
1476             if byte_order is None:
1477                 obj.byte_order = self._bo
1478             else:
1479                 if not _is_str_prop(byte_order):
1480                     raise ConfigError('"byte-order" property of floating point number type object must be a string ("le" or "be")')
1481
1482                 byte_order = _byte_order_str_to_bo(byte_order)
1483
1484                 if byte_order is None:
1485                     raise ConfigError('invalid "byte-order" property in floating point number type object')
1486         else:
1487             obj.byte_order = self._bo
1488
1489         return obj
1490
1491     def _create_enum(self, obj, node):
1492         if obj is None:
1493             # create enumeration object
1494             obj = metadata.Enum()
1495
1496         unk_prop = self._get_first_unknown_type_prop(node, [
1497             'value-type',
1498             'members',
1499         ])
1500
1501         if unk_prop:
1502             raise ConfigError('unknown enumeration type object property: "{}"'.format(unk_prop))
1503
1504         # value type
1505         if 'value-type' in node:
1506             value_type_node = node['value-type']
1507
1508             try:
1509                 obj.value_type = self._create_type(value_type_node)
1510             except Exception as e:
1511                 raise ConfigError('cannot create enumeration type\'s integer type', e)
1512
1513         # members
1514         if 'members' in node:
1515             members_node = node['members']
1516
1517             if not _is_array_prop(members_node):
1518                 raise ConfigError('"members" property of enumeration type object must be an array')
1519
1520             cur = 0
1521
1522             for index, m_node in enumerate(members_node):
1523                 if not _is_str_prop(m_node) and not _is_assoc_array_prop(m_node):
1524                     raise ConfigError('invalid enumeration member #{}: expecting a string or an associative array'.format(index))
1525
1526                 if _is_str_prop(m_node):
1527                     label = m_node
1528                     value = (cur, cur)
1529                     cur += 1
1530                 else:
1531                     unk_prop = _get_first_unknown_prop(m_node, [
1532                         'label',
1533                         'value',
1534                     ])
1535
1536                     if unk_prop:
1537                         raise ConfigError('unknown enumeration type member object property: "{}"'.format(unk_prop))
1538
1539                     if 'label' not in m_node:
1540                         raise ConfigError('missing "label" property in enumeration member #{}'.format(index))
1541
1542                     label = m_node['label']
1543
1544                     if not _is_str_prop(label):
1545                         raise ConfigError('"label" property of enumeration member #{} must be a string'.format(index))
1546
1547                     if 'value' not in m_node:
1548                         raise ConfigError('missing "value" property in enumeration member ("{}")'.format(label))
1549
1550                     value = m_node['value']
1551
1552                     if not _is_int_prop(value) and not _is_array_prop(value):
1553                         raise ConfigError('invalid enumeration member ("{}"): expecting an integer or an array'.format(label))
1554
1555                     if _is_int_prop(value):
1556                         cur = value + 1
1557                         value = (value, value)
1558                     else:
1559                         if len(value) != 2:
1560                             raise ConfigError('invalid enumeration member ("{}"): range must have exactly two items'.format(label))
1561
1562                         mn = value[0]
1563                         mx = value[1]
1564
1565                         if mn > mx:
1566                             raise ConfigError('invalid enumeration member ("{}"): invalid range ({} > {})'.format(label, mn, mx))
1567
1568                         value = (mn, mx)
1569                         cur = mx + 1
1570
1571                 obj.members[label] = value
1572
1573         return obj
1574
1575     def _create_string(self, obj, node):
1576         if obj is None:
1577             # create string object
1578             obj = metadata.String()
1579
1580         unk_prop = self._get_first_unknown_type_prop(node, [
1581             'encoding',
1582         ])
1583
1584         if unk_prop:
1585             raise ConfigError('unknown string type object property: "{}"'.format(unk_prop))
1586
1587         # encoding
1588         if 'encoding' in node:
1589             encoding = node['encoding']
1590
1591             if not _is_str_prop(encoding):
1592                 raise ConfigError('"encoding" property of string type object must be a string ("none", "ascii", or "utf-8")')
1593
1594             encoding = _encoding_str_to_encoding(encoding)
1595
1596             if encoding is None:
1597                 raise ConfigError('invalid "encoding" property in string type object')
1598
1599             obj.encoding = encoding
1600
1601         return obj
1602
1603     def _create_struct(self, obj, node):
1604         if obj is None:
1605             # create structure object
1606             obj = metadata.Struct()
1607
1608         unk_prop = self._get_first_unknown_type_prop(node, [
1609             'min-align',
1610             'fields',
1611         ])
1612
1613         if unk_prop:
1614             raise ConfigError('unknown string type object property: "{}"'.format(unk_prop))
1615
1616         # minimum alignment
1617         if 'min-align' in node:
1618             min_align = node['min-align']
1619
1620             if not _is_int_prop(min_align):
1621                 raise ConfigError('"min-align" property of structure type object must be an integer')
1622
1623             if not _is_valid_alignment(min_align):
1624                 raise ConfigError('invalid minimum alignment: {}'.format(min_align))
1625
1626             obj.min_align = min_align
1627
1628         # fields
1629         if 'fields' in node:
1630             fields = node['fields']
1631
1632             if not _is_assoc_array_prop(fields):
1633                 raise ConfigError('"fields" property of structure type object must be an associative array')
1634
1635             for field_name, field_node in fields.items():
1636                 if not is_valid_identifier(field_name):
1637                     raise ConfigError('"{}" is not a valid field name for structure type'.format(field_name))
1638
1639                 try:
1640                     obj.fields[field_name] = self._create_type(field_node)
1641                 except Exception as e:
1642                     raise ConfigError('cannot create structure type\'s field "{}"'.format(field_name), e)
1643
1644         return obj
1645
1646     def _create_array(self, obj, node):
1647         if obj is None:
1648             # create array object
1649             obj = metadata.Array()
1650
1651         unk_prop = self._get_first_unknown_type_prop(node, [
1652             'length',
1653             'element-type',
1654         ])
1655
1656         if unk_prop:
1657             raise ConfigError('unknown array type object property: "{}"'.format(unk_prop))
1658
1659         # length
1660         if 'length' in node:
1661             length = node['length']
1662
1663             if not _is_int_prop(length) and not _is_str_prop(length):
1664                 raise ConfigError('"length" property of array type object must be an integer or a string')
1665
1666             if type(length) is int and length < 0:
1667                 raise ConfigError('invalid static array length: {}'.format(length))
1668
1669             obj.length = length
1670
1671         # element type
1672         if 'element-type' in node:
1673             try:
1674                 obj.element_type = self._create_type(node['element-type'])
1675             except Exception as e:
1676                 raise ConfigError('cannot create array type\'s element type', e)
1677
1678         return obj
1679
1680     def _create_variant(self, obj, node):
1681         if obj is None:
1682             # create variant object
1683             obj = metadata.Variant()
1684
1685         unk_prop = self._get_first_unknown_type_prop(node, [
1686             'tag',
1687             'types',
1688         ])
1689
1690         if unk_prop:
1691             raise ConfigError('unknown variant type object property: "{}"'.format(unk_prop))
1692
1693         # tag
1694         if 'tag' in node:
1695             tag = node['tag']
1696
1697             if not _is_str_prop(tag):
1698                 raise ConfigError('"tag" property of variant type object must be a string')
1699
1700             # do not validate variant tag for the moment; will be done in a
1701             # second phase
1702             obj.tag = tag
1703
1704         # element type
1705         if 'types' in node:
1706             types = node['types']
1707
1708             if not _is_assoc_array_prop(types):
1709                 raise ConfigError('"types" property of variant type object must be an associative array')
1710
1711             # do not validate type names for the moment; will be done in a
1712             # second phase
1713             for type_name, type_node in types.items():
1714                 if not is_valid_identifier(type_name):
1715                     raise ConfigError('"{}" is not a valid type name for variant type'.format(type_name))
1716
1717                 try:
1718                     obj.types[type_name] = self._create_type(type_node)
1719                 except Exception as e:
1720                     raise ConfigError('cannot create variant type\'s type "{}"'.format(type_name), e)
1721
1722         return obj
1723
1724     def _create_type(self, type_node):
1725         if type(type_node) is str:
1726             t = self._lookup_type_alias(type_node)
1727
1728             if t is None:
1729                 raise ConfigError('unknown type alias "{}"'.format(type_node))
1730
1731             return t
1732
1733         if not _is_assoc_array_prop(type_node):
1734             raise ConfigError('type objects must be associative arrays or strings (type alias name)')
1735
1736         # inherit:
1737         #   v2.0:  "inherit"
1738         #   v2.1+: "$inherit"
1739         inherit_node = None
1740
1741         if self._version >= 200:
1742             if 'inherit' in type_node:
1743                 inherit_prop = 'inherit'
1744                 inherit_node = type_node[inherit_prop]
1745
1746         if self._version >= 201:
1747             if '$inherit' in type_node:
1748                 if inherit_node is not None:
1749                     raise ConfigError('cannot specify both "inherit" and "$inherit" properties of type object: prefer "$inherit"')
1750
1751                 inherit_prop = '$inherit'
1752                 inherit_node = type_node[inherit_prop]
1753
1754         if inherit_node is not None and 'class' in type_node:
1755             raise ConfigError('cannot specify both "{}" and "class" properties in type object'.format(inherit_prop))
1756
1757         if inherit_node is not None:
1758             if not _is_str_prop(inherit_node):
1759                 raise ConfigError('"{}" property of type object must be a string'.format(inherit_prop))
1760
1761             base = self._lookup_type_alias(inherit_node)
1762
1763             if base is None:
1764                 raise ConfigError('cannot inherit from type alias "{}": type alias does not exist at this point'.format(inherit_node))
1765
1766             func = self._type_to_create_type_func[type(base)]
1767         else:
1768             if 'class' not in type_node:
1769                 raise ConfigError('type objects which do not inherit must have a "class" property')
1770
1771             class_name = type_node['class']
1772
1773             if type(class_name) is not str:
1774                 raise ConfigError('type objects\' "class" property must be a string')
1775
1776             if class_name not in self._class_name_to_create_type_func:
1777                 raise ConfigError('unknown type class "{}"'.format(class_name))
1778
1779             base = None
1780             func = self._class_name_to_create_type_func[class_name]
1781
1782         return func(base, type_node)
1783
1784     def _register_type_aliases(self, metadata_node):
1785         self._tas = dict()
1786
1787         if 'type-aliases' not in metadata_node:
1788             return
1789
1790         ta_node = metadata_node['type-aliases']
1791
1792         if not _is_assoc_array_prop(ta_node):
1793             raise ConfigError('"type-aliases" property (metadata) must be an associative array')
1794
1795         for ta_name, ta_type in ta_node.items():
1796             if ta_name in self._tas:
1797                 raise ConfigError('duplicate type alias "{}"'.format(ta_name))
1798
1799             try:
1800                 t = self._create_type(ta_type)
1801             except Exception as e:
1802                 raise ConfigError('cannot create type alias "{}"'.format(ta_name), e)
1803
1804             self._tas[ta_name] = t
1805
1806     def _create_clock(self, node):
1807         # create clock object
1808         clock = metadata.Clock()
1809
1810         if not _is_assoc_array_prop(node):
1811             raise ConfigError('clock objects must be associative arrays')
1812
1813         known_props = [
1814             'uuid',
1815             'description',
1816             'freq',
1817             'error-cycles',
1818             'offset',
1819             'absolute',
1820             'return-ctype',
1821         ]
1822
1823         if self._version >= 201:
1824             known_props.append('$return-ctype')
1825
1826         unk_prop = _get_first_unknown_prop(node, known_props)
1827
1828         if unk_prop:
1829             raise ConfigError('unknown clock object property: "{}"'.format(unk_prop))
1830
1831         # UUID
1832         if 'uuid' in node:
1833             uuidp = node['uuid']
1834
1835             if not _is_str_prop(uuidp):
1836                 raise ConfigError('"uuid" property of clock object must be a string')
1837
1838             try:
1839                 uuidp = uuid.UUID(uuidp)
1840             except:
1841                 raise ConfigError('malformed UUID (clock object): "{}"'.format(uuidp))
1842
1843             clock.uuid = uuidp
1844
1845         # description
1846         if 'description' in node:
1847             desc = node['description']
1848
1849             if not _is_str_prop(desc):
1850                 raise ConfigError('"description" property of clock object must be a string')
1851
1852             clock.description = desc
1853
1854         # frequency
1855         if 'freq' in node:
1856             freq = node['freq']
1857
1858             if not _is_int_prop(freq):
1859                 raise ConfigError('"freq" property of clock object must be an integer')
1860
1861             if freq < 1:
1862                 raise ConfigError('invalid clock frequency: {}'.format(freq))
1863
1864             clock.freq = freq
1865
1866         # error cycles
1867         if 'error-cycles' in node:
1868             error_cycles = node['error-cycles']
1869
1870             if not _is_int_prop(error_cycles):
1871                 raise ConfigError('"error-cycles" property of clock object must be an integer')
1872
1873             if error_cycles < 0:
1874                 raise ConfigError('invalid clock error cycles: {}'.format(error_cycles))
1875
1876             clock.error_cycles = error_cycles
1877
1878         # offset
1879         if 'offset' in node:
1880             offset = node['offset']
1881
1882             if not _is_assoc_array_prop(offset):
1883                 raise ConfigError('"offset" property of clock object must be an associative array')
1884
1885             unk_prop = _get_first_unknown_prop(offset, ['cycles', 'seconds'])
1886
1887             if unk_prop:
1888                 raise ConfigError('unknown clock object\'s offset property: "{}"'.format(unk_prop))
1889
1890             # cycles
1891             if 'cycles' in offset:
1892                 offset_cycles = offset['cycles']
1893
1894                 if not _is_int_prop(offset_cycles):
1895                     raise ConfigError('"cycles" property of clock object\'s offset property must be an integer')
1896
1897                 if offset_cycles < 0:
1898                     raise ConfigError('invalid clock offset cycles: {}'.format(offset_cycles))
1899
1900                 clock.offset_cycles = offset_cycles
1901
1902             # seconds
1903             if 'seconds' in offset:
1904                 offset_seconds = offset['seconds']
1905
1906                 if not _is_int_prop(offset_seconds):
1907                     raise ConfigError('"seconds" property of clock object\'s offset property must be an integer')
1908
1909                 if offset_seconds < 0:
1910                     raise ConfigError('invalid clock offset seconds: {}'.format(offset_seconds))
1911
1912                 clock.offset_seconds = offset_seconds
1913
1914         # absolute
1915         if 'absolute' in node:
1916             absolute = node['absolute']
1917
1918             if not _is_bool_prop(absolute):
1919                 raise ConfigError('"absolute" property of clock object must be a boolean')
1920
1921             clock.absolute = absolute
1922
1923         # return C type:
1924         #   v2.0:  "return-ctype"
1925         #   v2.1+: "$return-ctype"
1926         return_ctype_node = None
1927
1928         if self._version >= 200:
1929             if 'return-ctype' in node:
1930                 return_ctype_prop = 'return-ctype'
1931                 return_ctype_node = node[return_ctype_prop]
1932
1933         if self._version >= 201:
1934             if '$return-ctype' in node:
1935                 if return_ctype_node is not None:
1936                     raise ConfigError('cannot specify both "return-ctype" and "$return-ctype" properties of clock object: prefer "$return-ctype"')
1937
1938                 return_ctype_prop = '$return-ctype'
1939                 return_ctype_node = node[return_ctype_prop]
1940
1941         if return_ctype_node is not None:
1942             if not _is_str_prop(return_ctype_node):
1943                 raise ConfigError('"{}" property of clock object must be a string'.format(return_ctype_prop))
1944
1945             clock.return_ctype = return_ctype_node
1946
1947         return clock
1948
1949     def _register_clocks(self, metadata_node):
1950         self._clocks = collections.OrderedDict()
1951
1952         if 'clocks' not in metadata_node:
1953             return
1954
1955         clocks_node = metadata_node['clocks']
1956
1957         if not _is_assoc_array_prop(clocks_node):
1958             raise ConfigError('"clocks" property (metadata) must be an associative array')
1959
1960         for clock_name, clock_node in clocks_node.items():
1961             if not is_valid_identifier(clock_name):
1962                 raise ConfigError('invalid clock name: "{}"'.format(clock_name))
1963
1964             if clock_name in self._clocks:
1965                 raise ConfigError('duplicate clock "{}"'.format(clock_name))
1966
1967             try:
1968                 clock = self._create_clock(clock_node)
1969             except Exception as e:
1970                 raise ConfigError('cannot create clock "{}"'.format(clock_name), e)
1971
1972             clock.name = clock_name
1973             self._clocks[clock_name] = clock
1974
1975     def _create_env(self, metadata_node):
1976         env = collections.OrderedDict()
1977
1978         if 'env' not in metadata_node:
1979             return env
1980
1981         env_node = metadata_node['env']
1982
1983         if not _is_assoc_array_prop(env_node):
1984             raise ConfigError('"env" property (metadata) must be an associative array')
1985
1986         for env_name, env_value in env_node.items():
1987             if env_name in env:
1988                 raise ConfigError('duplicate environment variable "{}"'.format(env_name))
1989
1990             if not is_valid_identifier(env_name):
1991                 raise ConfigError('invalid environment variable name: "{}"'.format(env_name))
1992
1993             if not _is_int_prop(env_value) and not _is_str_prop(env_value):
1994                 raise ConfigError('invalid environment variable value ("{}"): expecting integer or string'.format(env_name))
1995
1996             env[env_name] = env_value
1997
1998         return env
1999
2000     def _register_log_levels(self, metadata_node):
2001         self._log_levels = dict()
2002
2003         # log levels:
2004         #   v2.0:  "log-levels"
2005         #   v2.1+: "$log-levels"
2006         log_levels_node = None
2007
2008         if self._version >= 200:
2009             if 'log-levels' in metadata_node:
2010                 log_levels_prop = 'log-levels'
2011                 log_levels_node = metadata_node[log_levels_prop]
2012
2013         if self._version >= 201:
2014             if '$log-levels' in metadata_node:
2015                 if log_levels_node is not None:
2016                     raise ConfigError('cannot specify both "log-levels" and "$log-levels" properties of metadata object: prefer "$log-levels"')
2017
2018                 log_levels_prop = '$log-levels'
2019                 log_levels_node = metadata_node[log_levels_prop]
2020
2021         if log_levels_node is None:
2022             return
2023
2024         if not _is_assoc_array_prop(log_levels_node):
2025             raise ConfigError('"{}" property (metadata) must be an associative array'.format(log_levels_prop))
2026
2027         for ll_name, ll_value in log_levels_node.items():
2028             if ll_name in self._log_levels:
2029                 raise ConfigError('duplicate log level entry "{}"'.format(ll_name))
2030
2031             if not _is_int_prop(ll_value):
2032                 raise ConfigError('invalid log level entry ("{}"): expecting an integer'.format(ll_name))
2033
2034             if ll_value < 0:
2035                 raise ConfigError('invalid log level entry ("{}"): log level value must be positive'.format(ll_name))
2036
2037             self._log_levels[ll_name] = ll_value
2038
2039     def _create_trace(self, metadata_node):
2040         # create trace object
2041         trace = metadata.Trace()
2042
2043         if 'trace' not in metadata_node:
2044             raise ConfigError('missing "trace" property (metadata)')
2045
2046         trace_node = metadata_node['trace']
2047
2048         if not _is_assoc_array_prop(trace_node):
2049             raise ConfigError('"trace" property (metadata) must be an associative array')
2050
2051         unk_prop = _get_first_unknown_prop(trace_node, [
2052             'byte-order',
2053             'uuid',
2054             'packet-header-type',
2055         ])
2056
2057         if unk_prop:
2058             raise ConfigError('unknown trace object property: "{}"'.format(unk_prop))
2059
2060         # set byte order (already parsed)
2061         trace.byte_order = self._bo
2062
2063         # UUID
2064         if 'uuid' in trace_node:
2065             uuidp = trace_node['uuid']
2066
2067             if not _is_str_prop(uuidp):
2068                 raise ConfigError('"uuid" property of trace object must be a string')
2069
2070             if uuidp == 'auto':
2071                 uuidp = uuid.uuid1()
2072             else:
2073                 try:
2074                     uuidp = uuid.UUID(uuidp)
2075                 except:
2076                     raise ConfigError('malformed UUID (trace object): "{}"'.format(uuidp))
2077
2078             trace.uuid = uuidp
2079
2080         # packet header type
2081         if 'packet-header-type' in trace_node:
2082             try:
2083                 ph_type = self._create_type(trace_node['packet-header-type'])
2084             except Exception as e:
2085                 raise ConfigError('cannot create packet header type (trace)', e)
2086
2087             trace.packet_header_type = ph_type
2088
2089         return trace
2090
2091     def _lookup_log_level(self, ll):
2092         if _is_int_prop(ll):
2093             return ll
2094         elif _is_str_prop(ll) and ll in self._log_levels:
2095             return self._log_levels[ll]
2096
2097     def _create_event(self, event_node):
2098         event = metadata.Event()
2099
2100         if not _is_assoc_array_prop(event_node):
2101             raise ConfigError('event objects must be associative arrays')
2102
2103         unk_prop = _get_first_unknown_prop(event_node, [
2104             'log-level',
2105             'context-type',
2106             'payload-type',
2107         ])
2108
2109         if unk_prop:
2110             raise ConfigError('unknown event object property: "{}"'.format(unk_prop))
2111
2112         if 'log-level' in event_node:
2113             ll_node = event_node['log-level']
2114
2115             if _is_str_prop(ll_node):
2116                 ll_value = self._lookup_log_level(event_node['log-level'])
2117
2118                 if ll_value is None:
2119                     raise ConfigError('cannot find log level "{}"'.format(ll_node))
2120
2121                 ll = metadata.LogLevel(event_node['log-level'], ll_value)
2122             elif _is_int_prop(ll_node):
2123                 if ll_node < 0:
2124                     raise ConfigError('invalid log level value {}: value must be positive'.format(ll_node))
2125
2126                 ll = metadata.LogLevel(None, ll_node)
2127             else:
2128                 raise ConfigError('"log-level" property must be either a string or an integer')
2129
2130             event.log_level = ll
2131
2132         if 'context-type' in event_node:
2133             try:
2134                 t = self._create_type(event_node['context-type'])
2135             except Exception as e:
2136                 raise ConfigError('cannot create event\'s context type object', e)
2137
2138             event.context_type = t
2139
2140         if 'payload-type' not in event_node:
2141             raise ConfigError('missing "payload-type" property in event object')
2142
2143         try:
2144             t = self._create_type(event_node['payload-type'])
2145         except Exception as e:
2146             raise ConfigError('cannot create event\'s payload type object', e)
2147
2148         event.payload_type = t
2149
2150         return event
2151
2152     def _create_stream(self, stream_node):
2153         stream = metadata.Stream()
2154
2155         if not _is_assoc_array_prop(stream_node):
2156             raise ConfigError('stream objects must be associative arrays')
2157
2158         unk_prop = _get_first_unknown_prop(stream_node, [
2159             'packet-context-type',
2160             'event-header-type',
2161             'event-context-type',
2162             'events',
2163         ])
2164
2165         if unk_prop:
2166             raise ConfigError('unknown stream object property: "{}"'.format(unk_prop))
2167
2168         if 'packet-context-type' in stream_node:
2169             try:
2170                 t = self._create_type(stream_node['packet-context-type'])
2171             except Exception as e:
2172                 raise ConfigError('cannot create stream\'s packet context type object', e)
2173
2174             stream.packet_context_type = t
2175
2176         if 'event-header-type' in stream_node:
2177             try:
2178                 t = self._create_type(stream_node['event-header-type'])
2179             except Exception as e:
2180                 raise ConfigError('cannot create stream\'s event header type object', e)
2181
2182             stream.event_header_type = t
2183
2184         if 'event-context-type' in stream_node:
2185             try:
2186                 t = self._create_type(stream_node['event-context-type'])
2187             except Exception as e:
2188                 raise ConfigError('cannot create stream\'s event context type object', e)
2189
2190             stream.event_context_type = t
2191
2192         if 'events' not in stream_node:
2193             raise ConfigError('missing "events" property in stream object')
2194
2195         events = stream_node['events']
2196
2197         if not _is_assoc_array_prop(events):
2198             raise ConfigError('"events" property of stream object must be an associative array')
2199
2200         if not events:
2201             raise ConfigError('at least one event is needed within a stream object')
2202
2203         cur_id = 0
2204
2205         for ev_name, ev_node in events.items():
2206             try:
2207                 ev = self._create_event(ev_node)
2208             except Exception as e:
2209                 raise ConfigError('cannot create event "{}"'.format(ev_name), e)
2210
2211             ev.id = cur_id
2212             ev.name = ev_name
2213             stream.events[ev_name] = ev
2214             cur_id += 1
2215
2216         return stream
2217
2218     def _create_streams(self, metadata_node):
2219         streams = collections.OrderedDict()
2220
2221         if 'streams' not in metadata_node:
2222             raise ConfigError('missing "streams" property (metadata)')
2223
2224         streams_node = metadata_node['streams']
2225
2226         if not _is_assoc_array_prop(streams_node):
2227             raise ConfigError('"streams" property (metadata) must be an associative array')
2228
2229         if not streams_node:
2230             raise ConfigError('at least one stream is needed (metadata)')
2231
2232         cur_id = 0
2233
2234         for stream_name, stream_node in streams_node.items():
2235             try:
2236                 stream = self._create_stream(stream_node)
2237             except Exception as e:
2238                 raise ConfigError('cannot create stream "{}"'.format(stream_name), e)
2239
2240             stream.id = cur_id
2241             stream.name = str(stream_name)
2242             streams[stream_name] = stream
2243             cur_id += 1
2244
2245         return streams
2246
2247     def _create_metadata(self, root):
2248         meta = metadata.Metadata()
2249
2250         if 'metadata' not in root:
2251             raise ConfigError('missing "metadata" property (configuration)')
2252
2253         metadata_node = root['metadata']
2254
2255         if not _is_assoc_array_prop(metadata_node):
2256             raise ConfigError('"metadata" property (configuration) must be an associative array')
2257
2258         known_props = [
2259             'type-aliases',
2260             'log-levels',
2261             'trace',
2262             'env',
2263             'clocks',
2264             'streams',
2265         ]
2266
2267         if self._version >= 201:
2268             known_props.append('$log-levels')
2269
2270         unk_prop = _get_first_unknown_prop(metadata_node, known_props)
2271
2272         if unk_prop:
2273             add = ''
2274
2275             if unk_prop == '$include':
2276                 add = ' (use version 2.1 or greater)'
2277
2278             raise ConfigError('unknown metadata property{}: "{}"'.format(add, unk_prop))
2279
2280         self._set_byte_order(metadata_node)
2281         self._register_clocks(metadata_node)
2282         meta.clocks = self._clocks
2283         self._register_type_aliases(metadata_node)
2284         meta.env = self._create_env(metadata_node)
2285         meta.trace = self._create_trace(metadata_node)
2286         self._register_log_levels(metadata_node)
2287         meta.streams = self._create_streams(metadata_node)
2288
2289         return meta
2290
2291     def _get_version(self, root):
2292         if 'version' not in root:
2293             raise ConfigError('missing "version" property (configuration)')
2294
2295         version_node = root['version']
2296
2297         if not _is_str_prop(version_node):
2298             raise ConfigError('"version" property (configuration) must be a string')
2299
2300         version_node = version_node.strip()
2301
2302         if version_node not in ['2.0', '2.1']:
2303             raise ConfigError('unsupported version ({}): versions 2.0 and 2.1 are supported'.format(version_node))
2304
2305         # convert version string to comparable version integer
2306         parts = version_node.split('.')
2307         version = int(parts[0]) * 100 + int(parts[1])
2308
2309         return version
2310
2311     def _get_prefix(self, root):
2312         if 'prefix' not in root:
2313             return 'barectf_'
2314
2315         prefix_node = root['prefix']
2316
2317         if not _is_str_prop(prefix_node):
2318             raise ConfigError('"prefix" property (configuration) must be a string')
2319
2320         if not is_valid_identifier(prefix_node):
2321             raise ConfigError('"prefix" property (configuration) must be a valid C identifier')
2322
2323         return prefix_node
2324
2325     def _get_last_include_file(self):
2326         if self._include_stack:
2327             return self._include_stack[-1]
2328
2329         return self._root_yaml_path
2330
2331     def _load_include(self, yaml_path):
2332         for inc_dir in self._include_dirs:
2333             # current include dir + file name path
2334             # note: os.path.join() only takes the last arg if it's absolute
2335             inc_path = os.path.join(inc_dir, yaml_path)
2336
2337             # real path (symbolic links resolved)
2338             real_path = os.path.realpath(inc_path)
2339
2340             # normalized path (weird stuff removed!)
2341             norm_path = os.path.normpath(real_path)
2342
2343             if not os.path.isfile(norm_path):
2344                 # file does not exist: skip
2345                 continue
2346
2347             if norm_path in self._include_stack:
2348                 base_path = self._get_last_include_file()
2349                 raise ConfigError('in "{}": cannot recursively include file "{}"'.format(base_path, norm_path))
2350
2351             self._include_stack.append(norm_path)
2352
2353             # load raw content
2354             return self._yaml_ordered_load(norm_path)
2355
2356         if not self._ignore_include_not_found:
2357             base_path = self._get_last_include_file()
2358             raise ConfigError('in "{}": cannot include file "{}": file not found in include directories'.format(base_path, yaml_path))
2359
2360         return None
2361
2362     def _get_include_paths(self, include_node):
2363         if _is_str_prop(include_node):
2364             return [include_node]
2365         elif _is_array_prop(include_node):
2366             for include_path in include_node:
2367                 if not _is_str_prop(include_path):
2368                     raise ConfigError('invalid include property: expecting array of strings')
2369
2370             return include_node
2371
2372         raise ConfigError('invalid include property: expecting string or array of strings')
2373
2374     def _update_node(self, base_node, overlay_node):
2375         for olay_key, olay_value in overlay_node.items():
2376             if olay_key in base_node:
2377                 base_value = base_node[olay_key]
2378
2379                 if _is_assoc_array_prop(olay_value) and _is_assoc_array_prop(base_value):
2380                     # merge dictionaries
2381                     self._update_node(base_value, olay_value)
2382                 elif _is_array_prop(olay_value) and _is_array_prop(base_value):
2383                     # append extension array items to base items
2384                     base_value += olay_value
2385                 else:
2386                     # fall back to replacing
2387                     base_node[olay_key] = olay_value
2388             else:
2389                 base_node[olay_key] = olay_value
2390
2391     def _process_node_include(self, last_overlay_node, name,
2392                               process_base_include_cb,
2393                               process_children_include_cb=None):
2394         if not _is_assoc_array_prop(last_overlay_node):
2395             raise ConfigError('{} objects must be associative arrays'.format(name))
2396
2397         # process children inclusions first
2398         if process_children_include_cb:
2399             process_children_include_cb(last_overlay_node)
2400
2401         if '$include' in last_overlay_node:
2402             include_node = last_overlay_node['$include']
2403         else:
2404             # no includes!
2405             return last_overlay_node
2406
2407         include_paths = self._get_include_paths(include_node)
2408         cur_base_path = self._get_last_include_file()
2409         base_node = None
2410
2411         # keep the include paths and remove the include property
2412         include_paths = copy.deepcopy(include_paths)
2413         del last_overlay_node['$include']
2414
2415         for include_path in include_paths:
2416             # load raw YAML from included file
2417             overlay_node = self._load_include(include_path)
2418
2419             if overlay_node is None:
2420                 # cannot find include file, but we're ignoring those
2421                 # errors, otherwise _load_include() itself raises
2422                 # a config error
2423                 continue
2424
2425             # recursively process includes
2426             try:
2427                 overlay_node = process_base_include_cb(overlay_node)
2428             except Exception as e:
2429                 raise ConfigError('in "{}"'.format(cur_base_path), e)
2430
2431             # pop include stack now that we're done including
2432             del self._include_stack[-1]
2433
2434             # at this point, base_node is fully resolved (does not
2435             # contain any include property)
2436             if base_node is None:
2437                 base_node = overlay_node
2438             else:
2439                 self._update_node(base_node, overlay_node)
2440
2441         # finally, we update the latest base node with our last overlay
2442         # node
2443         if base_node is None:
2444             # nothing was included, which is possible when we're
2445             # ignoring include errors
2446             return last_overlay_node
2447
2448         self._update_node(base_node, last_overlay_node)
2449
2450         return base_node
2451
2452     def _process_event_include(self, event_node):
2453         return self._process_node_include(event_node, 'event',
2454                                           self._process_event_include)
2455
2456     def _process_stream_include(self, stream_node):
2457         def process_children_include(stream_node):
2458             if 'events' in stream_node:
2459                 events_node = stream_node['events']
2460
2461                 if not _is_assoc_array_prop(events_node):
2462                     raise ConfigError('"events" property must be an associative array')
2463
2464                 events_node_keys = list(events_node.keys())
2465
2466                 for key in events_node_keys:
2467                     event_node = events_node[key]
2468
2469                     try:
2470                         events_node[key] = self._process_event_include(event_node)
2471                     except Exception as e:
2472                         raise ConfigError('cannot process includes of event object "{}"'.format(key), e)
2473
2474         return self._process_node_include(stream_node, 'stream',
2475                                           self._process_stream_include,
2476                                           process_children_include)
2477
2478     def _process_trace_include(self, trace_node):
2479         return self._process_node_include(trace_node, 'trace',
2480                                           self._process_trace_include)
2481
2482     def _process_clock_include(self, clock_node):
2483         return self._process_node_include(clock_node, 'clock',
2484                                           self._process_clock_include)
2485
2486     def _process_metadata_include(self, metadata_node):
2487         def process_children_include(metadata_node):
2488             if 'trace' in metadata_node:
2489                 metadata_node['trace'] = self._process_trace_include(metadata_node['trace'])
2490
2491             if 'clocks' in metadata_node:
2492                 clocks_node = metadata_node['clocks']
2493
2494                 if not _is_assoc_array_prop(clocks_node):
2495                     raise ConfigError('"clocks" property (metadata) must be an associative array')
2496
2497                 clocks_node_keys = list(clocks_node.keys())
2498
2499                 for key in clocks_node_keys:
2500                     clock_node = clocks_node[key]
2501
2502                     try:
2503                         clocks_node[key] = self._process_clock_include(clock_node)
2504                     except Exception as e:
2505                         raise ConfigError('cannot process includes of clock object "{}"'.format(key), e)
2506
2507             if 'streams' in metadata_node:
2508                 streams_node = metadata_node['streams']
2509
2510                 if not _is_assoc_array_prop(streams_node):
2511                     raise ConfigError('"streams" property (metadata) must be an associative array')
2512
2513                 streams_node_keys = list(streams_node.keys())
2514
2515                 for key in streams_node_keys:
2516                     stream_node = streams_node[key]
2517
2518                     try:
2519                         streams_node[key] = self._process_stream_include(stream_node)
2520                     except Exception as e:
2521                         raise ConfigError('cannot process includes of stream object "{}"'.format(key), e)
2522
2523         return self._process_node_include(metadata_node, 'metadata',
2524                                           self._process_metadata_include,
2525                                           process_children_include)
2526
2527     def _process_root_includes(self, root):
2528         # The following config objects support includes:
2529         #
2530         #   * Metadata object
2531         #   * Trace object
2532         #   * Stream object
2533         #   * Event object
2534         #
2535         # We need to process the event includes first, then the stream
2536         # includes, then the trace includes, and finally the metadata
2537         # includes.
2538         #
2539         # In each object, only one of the $include and $include-replace
2540         # special properties is allowed.
2541         #
2542         # We keep a stack of absolute paths to included files to detect
2543         # recursion.
2544         if 'metadata' in root:
2545             root['metadata'] = self._process_metadata_include(root['metadata'])
2546
2547         return root
2548
2549     def _yaml_ordered_dump(self, node, **kwds):
2550         class ODumper(yaml.Dumper):
2551             pass
2552
2553         def dict_representer(dumper, node):
2554             return dumper.represent_mapping(yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG,
2555                                             node.items())
2556
2557         ODumper.add_representer(collections.OrderedDict, dict_representer)
2558
2559         return yaml.dump(node, Dumper=ODumper, **kwds)
2560
2561     def _yaml_ordered_load(self, yaml_path):
2562         class OLoader(yaml.Loader):
2563             pass
2564
2565         def construct_mapping(loader, node):
2566             loader.flatten_mapping(node)
2567
2568             return collections.OrderedDict(loader.construct_pairs(node))
2569
2570         OLoader.add_constructor(yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG,
2571                                 construct_mapping)
2572
2573         # YAML -> Python
2574         try:
2575             with open(yaml_path, 'r') as f:
2576                 node = yaml.load(f, OLoader)
2577         except (OSError, IOError) as e:
2578             raise ConfigError('cannot open file "{}"'.format(yaml_path))
2579         except Exception as e:
2580             raise ConfigError('unknown error while trying to load file "{}"'.format(yaml_path), e)
2581
2582         # loaded node must be an associate array
2583         if not _is_assoc_array_prop(node):
2584             raise ConfigError('root of YAML file "{}" must be an associative array'.format(yaml_path))
2585
2586         return node
2587
2588     def _reset(self):
2589         self._version = None
2590         self._include_stack = []
2591
2592     def parse(self, yaml_path):
2593         self._reset()
2594         self._root_yaml_path = yaml_path
2595
2596         try:
2597             root = self._yaml_ordered_load(yaml_path)
2598         except Exception as e:
2599             raise ConfigError('cannot parse YAML file "{}"'.format(yaml_path), e)
2600
2601         if not _is_assoc_array_prop(root):
2602             raise ConfigError('configuration must be an associative array')
2603
2604         unk_prop = _get_first_unknown_prop(root, [
2605             'version',
2606             'prefix',
2607             'metadata',
2608         ])
2609
2610         if unk_prop:
2611             raise ConfigError('unknown configuration property: "{}"'.format(unk_prop))
2612
2613         # get the config version
2614         self._version = self._get_version(root)
2615
2616         # process includes if supported
2617         if self._version >= 201:
2618             root = self._process_root_includes(root)
2619
2620         # dump config if required
2621         if self._dump_config:
2622             print(self._yaml_ordered_dump(root, indent=2,
2623                                           default_flow_style=False))
2624
2625         # get prefix and metadata
2626         prefix = self._get_prefix(root)
2627         meta = self._create_metadata(root)
2628
2629         return Config(self._version, prefix, meta)
2630
2631
2632 def from_yaml_file(path, include_dirs, ignore_include_not_found, dump_config):
2633     try:
2634         parser = _YamlConfigParser(include_dirs, ignore_include_not_found,
2635                                    dump_config)
2636         cfg = parser.parse(path)
2637
2638         return cfg
2639     except Exception as e:
2640         raise ConfigError('cannot create configuration from YAML file "{}"'.format(path), e)