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Return a new value to mutate a field with. Do not modify the field directly in this function. Override the ``mutate()`` function if that is needed (the field is only passed into this function as a reference). :field: The pfp.fields.Field instance that will receive the new value. Passed in for reference only. :returns: The next value for the field def next_val(self, field): """Return a new value to mutate a field with. Do not modify the field directly in this function. Override the ``mutate()`` function if that is needed (the field is only passed into this function as a reference). :field: The pfp.fields.Field instance that will receive the new value. Passed in for reference only. :returns: The next value for the field """ import pfp.fuzz.rand as rand if self.choices is not None: choices = self._resolve_member_val(self.choices, field) new_val = rand.choice(choices) return self._resolve_val(new_val) elif self.prob is not None: prob = self._resolve_member_val(self.prob, field) rand_val = rand.random() curr_total = 0.0 # iterate through each of the probability choices until # we reach one that matches the current rand_val for prob_percent, prob_val in prob: if rand_val <= curr_total + prob_percent: return self._resolve_val(prob_val) curr_total += prob_percent raise MutationError("probabilities did not add up to 100%! {}".format( [str(x[0]) + " - " + str(x[1])[:10] for x in prob] ))
generate a new user in the database, still session based so we create a new identifier. def generate_subid(self, token=None, return_user=False): '''generate a new user in the database, still session based so we create a new identifier. ''' from expfactory.database.models import Participant if not token: p = Participant() else: p = Participant(token=token) self.session.add(p) self.session.commit() if return_user is True: return p return p.id
print a relational database user def print_user(self, user): '''print a relational database user ''' status = "active" token = user.token if token in ['finished', 'revoked']: status = token if token is None: token = '' subid = "%s\t%s[%s]" %(user.id, token, status) print(subid) return subid
list users, each having a model in the database. A headless experiment will use protected tokens, and interactive will be based on auto- incremented ids. def list_users(self, user=None): '''list users, each having a model in the database. A headless experiment will use protected tokens, and interactive will be based on auto- incremented ids. ''' from expfactory.database.models import Participant participants = Participant.query.all() users = [] for user in participants: users.append(self.print_user(user)) return users
generate a new user in the database, still session based so we create a new identifier. This function is called from the users new entrypoint, and it assumes we want a user generated with a token. def generate_user(self): '''generate a new user in the database, still session based so we create a new identifier. This function is called from the users new entrypoint, and it assumes we want a user generated with a token. ''' token = str(uuid.uuid4()) return self.generate_subid(token=token, return_user=True)
finish user will remove a user's token, making the user entry not accesible if running in headless model def finish_user(self, subid): '''finish user will remove a user's token, making the user entry not accesible if running in headless model''' p = self.revoke_token(subid) p.token = "finished" self.session.commit() return p
restart a user, which means revoking and issuing a new token. def restart_user(self, subid): '''restart a user, which means revoking and issuing a new token.''' p = self.revoke_token(subid) p = self.refresh_token(subid) return p
retrieve a subject based on a token. Valid means we return a participant invalid means we return None def validate_token(self, token): '''retrieve a subject based on a token. Valid means we return a participant invalid means we return None ''' from expfactory.database.models import Participant p = Participant.query.filter(Participant.token == token).first() if p is not None: if p.token.endswith(('finished','revoked')): p = None else: p = p.id return p
revoke a token by removing it. Is done at finish, and also available as a command line option def revoke_token(self, subid): '''revoke a token by removing it. Is done at finish, and also available as a command line option''' from expfactory.database.models import Participant p = Participant.query.filter(Participant.id == subid).first() if p is not None: p.token = 'revoked' self.session.commit() return p
refresh or generate a new token for a user def refresh_token(self, subid): '''refresh or generate a new token for a user''' from expfactory.database.models import Participant p = Participant.query.filter(Participant.id == subid).first() if p is not None: p.token = str(uuid.uuid4()) self.session.commit() return p
save data will obtain the current subid from the session, and save it depending on the database type. Currently we just support flat files def save_data(self,session, exp_id, content): '''save data will obtain the current subid from the session, and save it depending on the database type. Currently we just support flat files''' from expfactory.database.models import ( Participant, Result ) subid = session.get('subid') token = session.get('token') self.logger.info('Saving data for subid %s' % subid) # We only attempt save if there is a subject id, set at start if subid is not None: p = Participant.query.filter(Participant.id == subid).first() # better query here # Does if self.headless and p.token != token: self.logger.warning('%s attempting to use mismatched token [%s] skipping save' %(p.id, token)) elif self.headless and p.token.endswith(('finished','revoked')): self.logger.warning('%s attempting to use expired token [%s] skipping save' %(p.id, token)) else: # Preference is to save data under 'data', otherwise do all of it if "data" in content: content = content['data'] result = Result(data=content, exp_id=exp_id, participant_id=p.id) # check if changes from str/int # Create and save the result self.session.add(result) p.results.append(result) self.session.commit() self.logger.info("Save [participant] %s [result] %s" %(p, result))
initialize the database, with the default database path or custom with a format corresponding to the database type: Examples: sqlite:////scif/data/expfactory.db def init_db(self): '''initialize the database, with the default database path or custom with a format corresponding to the database type: Examples: sqlite:////scif/data/expfactory.db ''' # The user can provide a custom string if self.database is None: self.logger.error("You must provide a database url, exiting.") sys.exit(1) self.engine = create_engine(self.database, convert_unicode=True) self.session = scoped_session(sessionmaker(autocommit=False, autoflush=False, bind=self.engine)) # Database Setup Base.query = self.session.query_property() # import all modules here that might define models so that # they will be registered properly on the metadata. Otherwise # you will have to import them first before calling init_db() import expfactory.database.models self.Base = Base self.Base.metadata.create_all(bind=self.engine)
Super non-standard stuff here. Dynamically changing the base class using the scope and the lazy name when the class is instantiated. This works as long as the original base class is not directly inheriting from object (which we're not, since our original base class is fields.Field). def LazyField(lookup_name, scope): """Super non-standard stuff here. Dynamically changing the base class using the scope and the lazy name when the class is instantiated. This works as long as the original base class is not directly inheriting from object (which we're not, since our original base class is fields.Field). """ def __init__(self, stream=None): base_cls = self._pfp__scope.get_id(self._pfp__lazy_name) self.__class__.__bases__ = (base_cls,) base_cls.__init__(self, stream) new_class = type(lookup_name + "_lazy", (fields.Field,), { "__init__" : __init__, "_pfp__scope" : scope, "_pfp__lazy_name" : lookup_name }) return new_class
Wrap the creation of the type so that we can provide a null-stream to initialize it def _wrap_type_instantiation(self, type_cls): """Wrap the creation of the type so that we can provide a null-stream to initialize it""" def wrapper(*args, **kwargs): # use args for struct arguments?? return type_cls(stream=self._null_stream) return wrapper
Return the current scope level def level(self): """Return the current scope level """ res = len(self._scope_stack) if self._parent is not None: res += self._parent.level() return res
Create a new scope :returns: TODO def push(self, new_scope=None): """Create a new scope :returns: TODO """ if new_scope is None: new_scope = { "types": {}, "vars": {} } self._curr_scope = new_scope self._dlog("pushing new scope, scope level = {}".format(self.level())) self._scope_stack.append(self._curr_scope)
Return a new Scope object that has the curr_scope pinned at the current one :returns: A new scope object def clone(self): """Return a new Scope object that has the curr_scope pinned at the current one :returns: A new scope object """ self._dlog("cloning the stack") # TODO is this really necessary to create a brand new one? # I think it is... need to think about it more. # or... are we going to need ref counters and a global # scope object that allows a view into (or a snapshot of) # a specific scope stack? res = Scope(self._log) res._scope_stack = self._scope_stack res._curr_scope = self._curr_scope return res
Leave the current scope :returns: TODO def pop(self): """Leave the current scope :returns: TODO """ res = self._scope_stack.pop() self._dlog("popping scope, scope level = {}".format(self.level())) self._curr_scope = self._scope_stack[-1] return res
Add a var to the current scope (vars are fields that parse the input stream) :field_name: TODO :field: TODO :returns: TODO def add_var(self, field_name, field, root=False): """Add a var to the current scope (vars are fields that parse the input stream) :field_name: TODO :field: TODO :returns: TODO """ self._dlog("adding var '{}' (root={})".format(field_name, root)) # do both so it's not clobbered by intermediate values of the same name if root: self._scope_stack[0]["vars"][field_name] = field # TODO do we allow clobbering of vars??? self._curr_scope["vars"][field_name] = field
Return the first var of name ``name`` in the current scope stack (remember, vars are the ones that parse the input stream) :name: The name of the id :recurse: Whether parent scopes should also be searched (defaults to True) :returns: TODO def get_var(self, name, recurse=True): """Return the first var of name ``name`` in the current scope stack (remember, vars are the ones that parse the input stream) :name: The name of the id :recurse: Whether parent scopes should also be searched (defaults to True) :returns: TODO """ self._dlog("getting var '{}'".format(name)) return self._search("vars", name, recurse)
Add a local variable in the current scope :field_name: The field's name :field: The field :returns: None def add_local(self, field_name, field): """Add a local variable in the current scope :field_name: The field's name :field: The field :returns: None """ self._dlog("adding local '{}'".format(field_name)) field._pfp__name = field_name # TODO do we allow clobbering of locals??? self._curr_scope["vars"][field_name] = field
Get the local field (search for it) from the scope stack. An alias for ``get_var`` :name: The name of the local field def get_local(self, name, recurse=True): """Get the local field (search for it) from the scope stack. An alias for ``get_var`` :name: The name of the local field """ self._dlog("getting local '{}'".format(name)) return self._search("vars", name, recurse)
Store the node with the name. When it is instantiated, the node itself will be handled. :name: name of the typedefd struct/union :node: the union/struct node :interp: the 010 interpreter def add_type_struct_or_union(self, name, interp, node): """Store the node with the name. When it is instantiated, the node itself will be handled. :name: name of the typedefd struct/union :node: the union/struct node :interp: the 010 interpreter """ self.add_type_class(name, StructUnionDef(name, interp, node))
Record the typedefd name for orig_names. Resolve orig_names to their core names and save those. :new_name: TODO :orig_names: TODO :returns: TODO def add_type(self, new_name, orig_names): """Record the typedefd name for orig_names. Resolve orig_names to their core names and save those. :new_name: TODO :orig_names: TODO :returns: TODO """ self._dlog("adding a type '{}'".format(new_name)) # TODO do we allow clobbering of types??? res = copy.copy(orig_names) resolved_names = self._resolve_name(res[-1]) if resolved_names is not None: res.pop() res += resolved_names self._curr_scope["types"][new_name] = res
Get the names for the typename (created by typedef) :name: The typedef'd name to resolve :returns: An array of resolved names associated with the typedef'd name def get_type(self, name, recurse=True): """Get the names for the typename (created by typedef) :name: The typedef'd name to resolve :returns: An array of resolved names associated with the typedef'd name """ self._dlog("getting type '{}'".format(name)) return self._search("types", name, recurse)
Get the first id matching ``name``. Will either be a local or a var. :name: TODO :returns: TODO def get_id(self, name, recurse=True): """Get the first id matching ``name``. Will either be a local or a var. :name: TODO :returns: TODO """ self._dlog("getting id '{}'".format(name)) var = self._search("vars", name, recurse) return var
TODO: Docstring for _resolve_names. :name: TODO :returns: TODO def _resolve_name(self, name): """TODO: Docstring for _resolve_names. :name: TODO :returns: TODO """ res = [name] while True: orig_names = self._search("types", name) if orig_names is not None: name = orig_names[-1] # pop off the typedefd name res.pop() # add back on the original names res += orig_names else: break return res
Search the scope stack for the name in the specified category (types/locals/vars). :category: the category to search in (locals/types/vars) :name: name to search for :returns: None if not found, the result of the found local/type/id def _search(self, category, name, recurse=True): """Search the scope stack for the name in the specified category (types/locals/vars). :category: the category to search in (locals/types/vars) :name: name to search for :returns: None if not found, the result of the found local/type/id """ idx = len(self._scope_stack) - 1 curr = self._curr_scope for scope in reversed(self._scope_stack): res = scope[category].get(name, None) if res is not None: return res if recurse and self._parent is not None: return self._parent._search(category, name, recurse) return None
Add the native python function ``func`` into the pfp interpreter with the name ``name`` and return value ``ret`` so that it can be called from within a template script. .. note:: The :any:`@native <pfp.native.native>` decorator exists to simplify this. All native functions must have the signature ``def func(params, ctxt, scope, stream, coord [,interp])``, optionally allowing an interpreter param if ``send_interp`` is ``True``. Example: The example below defines a function ``Sum`` using the ``add_native`` method. :: import pfp.fields from pfp.fields import PYVAL def native_sum(params, ctxt, scope, stream, coord): return PYVAL(params[0]) + PYVAL(params[1]) pfp.interp.PfpInterp.add_native("Sum", native_sum, pfp.fields.Int64) :param basestring name: The name the function will be exposed as in the interpreter. :param function func: The native python function that will be referenced. :param type(pfp.fields.Field) ret: The field class that the return value should be cast to. :param pfp.interp.PfpInterp interp: The specific pfp interpreter the function should be defined in. :param bool send_interp: If true, the current pfp interpreter will be added as an argument to the function. def add_native(cls, name, func, ret, interp=None, send_interp=False): """Add the native python function ``func`` into the pfp interpreter with the name ``name`` and return value ``ret`` so that it can be called from within a template script. .. note:: The :any:`@native <pfp.native.native>` decorator exists to simplify this. All native functions must have the signature ``def func(params, ctxt, scope, stream, coord [,interp])``, optionally allowing an interpreter param if ``send_interp`` is ``True``. Example: The example below defines a function ``Sum`` using the ``add_native`` method. :: import pfp.fields from pfp.fields import PYVAL def native_sum(params, ctxt, scope, stream, coord): return PYVAL(params[0]) + PYVAL(params[1]) pfp.interp.PfpInterp.add_native("Sum", native_sum, pfp.fields.Int64) :param basestring name: The name the function will be exposed as in the interpreter. :param function func: The native python function that will be referenced. :param type(pfp.fields.Field) ret: The field class that the return value should be cast to. :param pfp.interp.PfpInterp interp: The specific pfp interpreter the function should be defined in. :param bool send_interp: If true, the current pfp interpreter will be added as an argument to the function. """ if interp is None: natives = cls._natives else: # the instance's natives natives = interp._natives natives[name] = functions.NativeFunction( name, func, ret, send_interp )
Define the native functions for PFP def define_natives(cls): """Define the native functions for PFP """ if len(cls._natives) > 0: return glob_pattern = os.path.join(os.path.dirname(__file__), "native", "*.py") for filename in glob.glob(glob_pattern): basename = os.path.basename(filename).replace(".py", "") if basename == "__init__": continue try: mod_base = __import__("pfp.native", globals(), locals(), fromlist=[basename]) except Exception as e: sys.stderr.write("cannot import native module {} at '{}'".format(basename, filename)) raise e continue mod = getattr(mod_base, basename) setattr(mod, "PYVAL", fields.get_value) setattr(mod, "PYSTR", fields.get_str)
log the message to the log def _dlog(self, msg, indent_increase=0): """log the message to the log""" self._log.debug("interp", msg, indent_increase, filename=self._orig_filename, coord=self._coord)
Parse the data stream using the template (e.g. parse the 010 template and interpret the template using the stream as the data source). :stream: The input data stream :template: The template to parse the stream with :keep_successful: Return whatever was successfully parsed before an error. ``_pfp__error`` will contain the exception (if one was raised) :param bool printf: If ``False``, printfs will be noops (default=``True``) :returns: Pfp Dom def parse(self, stream, template, predefines=True, orig_filename=None, keep_successful=False, printf=True): """Parse the data stream using the template (e.g. parse the 010 template and interpret the template using the stream as the data source). :stream: The input data stream :template: The template to parse the stream with :keep_successful: Return whatever was successfully parsed before an error. ``_pfp__error`` will contain the exception (if one was raised) :param bool printf: If ``False``, printfs will be noops (default=``True``) :returns: Pfp Dom """ self._dlog("parsing") self._printf = printf self._orig_filename = orig_filename self._stream = stream self._template = template self._template_lines = self._template.split("\n") self._ast = self._parse_string(template, predefines) self._dlog("parsed template into ast") res = self._run(keep_successful) return res
Eval a single statement (something returnable) def eval(self, statement, ctxt=None): """Eval a single statement (something returnable) """ self._no_debug = True statement = statement.strip() if not statement.endswith(";"): statement += ";" ast = self._parse_string(statement, predefines=False) self._dlog("evaluating statement: {}".format(statement)) try: res = None for child in ast.children(): res = self._handle_node(child, self._scope, self._ctxt, self._stream) return res except errors.InterpReturn as e: return e.value finally: self._no_debug = False
Set if the interpreter should break. :returns: TODO def set_break(self, break_type): """Set if the interpreter should break. :returns: TODO """ self._break_type = break_type self._break_level = self._scope.level()
Return the current line number in the template, as well as the surrounding source lines def get_curr_lines(self): """Return the current line number in the template, as well as the surrounding source lines """ start = max(0, self._coord.line - 5) end = min(len(self._template_lines), self._coord.line + 4) lines = [(x, self._template_lines[x]) for x in six.moves.range(start, end, 1)] return self._coord.line, lines
Set if the bitfield input/output stream should be padded :val: True/False :returns: None def set_bitfield_padded(self, val): """Set if the bitfield input/output stream should be padded :val: True/False :returns: None """ self._padded_bitfield = val self._stream.padded = val self._ctxt._pfp__padded_bitfield = val
Interpret the parsed 010 AST :returns: PfpDom def _run(self, keep_successfull): """Interpret the parsed 010 AST :returns: PfpDom """ # example self._ast.show(): # FileAST: # Decl: data, [], [], [] # TypeDecl: data, [] # Struct: DATA # Decl: a, [], [], [] # TypeDecl: a, [] # IdentifierType: ['char'] # Decl: b, [], [], [] # TypeDecl: b, [] # IdentifierType: ['char'] # Decl: c, [], [], [] # TypeDecl: c, [] # IdentifierType: ['char'] # Decl: d, [], [], [] # TypeDecl: d, [] # IdentifierType: ['char'] self._dlog("interpreting template") try: # it is important to pass the stream in as the stream # may change (e.g. compressed data) res = self._handle_node(self._ast, None, None, self._stream) except errors.InterpReturn as e: # TODO handle exit/return codes (e.g. return -1) res = self._root except errors.InterpExit as e: res = self._root except Exception as e: if keep_successfull: # return the root and set _pfp__error res = self._root res._pfp__error = e else: exc_type, exc_obj, traceback = sys.exc_info() more_info = "\nException at {}:{}".format( self._orig_filename, self._coord.line ) six.reraise( errors.PfpError, errors.PfpError(exc_obj.__class__.__name__ + ": " + exc_obj.args[0] + more_info if len(exc_obj.args) > 0 else more_info), traceback ) # final drop-in after everything has executed if self._break_type != self.BREAK_NONE: self.debugger.cmdloop("execution finished") types = self.get_types() res._pfp__types = types return res
Recursively handle nodes in the 010 AST :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_node(self, node, scope=None, ctxt=None, stream=None): """Recursively handle nodes in the 010 AST :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ if scope is None: if self._scope is None: self._scope = scope = self._create_scope() else: scope = self._scope if ctxt is None and self._ctxt is not None: ctxt = self._ctxt else: self._ctxt = ctxt if type(node) is tuple: node = node[1] # TODO probably a better way to do this... # this occurs with if-statements that have a single statement # instead of a compound statement (no curly braces) elif type(node) is list and len(list(filter(lambda x: isinstance(x, AST.Node), node))) == len(node): node = AST.Compound( block_items=node, coord=node[0].coord ) return self._handle_node(node, scope, ctxt, stream) # need to check this so that debugger-eval'd statements # don't mess with the current state if not self._no_debug: self._coord = node.coord self._dlog("handling node type {}, line {}".format(node.__class__.__name__, node.coord.line if node.coord is not None else "?")) self._log.inc() breakable = self._node_is_breakable(node) if breakable and not self._no_debug and self._break_type != self.BREAK_NONE: # always break if self._break_type == self.BREAK_INTO: self._break_level = self._scope.level() self.debugger.cmdloop() # level <= _break_level elif self._break_type == self.BREAK_OVER: if self._scope.level() <= self._break_level: self._break_level = self._scope.level() self.debugger.cmdloop() else: pass if node.__class__ not in self._node_switch: raise errors.UnsupportedASTNode(node.coord, node.__class__.__name__) res = self._node_switch[node.__class__](node, scope, ctxt, stream) self._log.dec() return res
TODO: Docstring for _handle_file_ast. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_file_ast(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_file_ast. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._root = ctxt = fields.Dom(stream) ctxt._pfp__scope = scope self._root._pfp__name = "__root" self._root._pfp__interp = self self._dlog("handling file AST with {} children".format(len(node.children()))) for child in node.children(): self._handle_node(child, scope, ctxt, stream) ctxt._pfp__process_fields_metadata() return ctxt
Handle cast nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_cast(self, node, scope, ctxt, stream): """Handle cast nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling cast") to_type = self._handle_node(node.to_type, scope, ctxt, stream) val_to_cast = self._handle_node(node.expr, scope, ctxt, stream) res = to_type() res._pfp__set_value(val_to_cast) return res
TODO: Docstring for _handle_typename :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_typename(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_typename :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling typename") return self._handle_node(node.type, scope, ctxt, stream)
Get the name of the node - check for node.name and node.type.declname. Not sure why the second one occurs exactly - it happens with declaring a new struct field with parameters def _get_node_name(self, node): """Get the name of the node - check for node.name and node.type.declname. Not sure why the second one occurs exactly - it happens with declaring a new struct field with parameters""" res = getattr(node, "name", None) if res is None: return res if isinstance(res, AST.TypeDecl): return res.declname return res
TODO: Docstring for _handle_decl. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_decl(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_decl. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling decl") metadata_processor = None if node.metadata is not None: #metadata_info = self._handle_metadata(node, scope, ctxt, stream) def process_metadata(): metadata_info = self._handle_metadata(node, scope, ctxt, stream) return metadata_info metadata_processor = process_metadata field_name = self._get_node_name(node) field = self._handle_node(node.type, scope, ctxt, stream) bitsize = None bitfield_rw = None if getattr(node, "bitsize", None) is not None: bitsize = self._handle_node(node.bitsize, scope, ctxt, stream) has_prev = len(ctxt._pfp__children) > 0 bitfield_rw = None if has_prev: prev = ctxt._pfp__children[-1] # if it was a bitfield as well # TODO I don't think this will handle multiple bitfield groups in a row. # E.g. # char a: 8, b:8; # char c: 8, d:8; if ((self._padded_bitfield and prev.__class__.width == field.width) or not self._padded_bitfield) \ and prev.bitsize is not None and prev.bitfield_rw.reserve_bits(bitsize, stream): bitfield_rw = prev.bitfield_rw # either because there was no previous bitfield, or the previous was full if bitfield_rw is None: bitfield_rw = fields.BitfieldRW(self, field) bitfield_rw.reserve_bits(bitsize, stream) if getattr(node, "is_func_param", False): # we want to keep this as a class and not instantiate it # instantiation will be done in functions.ParamListDef.instantiate field = (field_name, field) # locals and consts still get a field instance, but DON'T parse the # stream! elif "local" in node.quals or "const" in node.quals: is_struct = issubclass(field, fields.Struct) if not isinstance(field, fields.Field) and not is_struct: field = field() scope.add_local(field_name, field) # this should only be able to be done with locals, right? # if not, move it to the bottom of the function if node.init is not None: val = self._handle_node(node.init, scope, ctxt, stream) if is_struct: field = val scope.add_local(field_name, field) else: field._pfp__set_value(val) if "const" in node.quals: field._pfp__freeze() field._pfp__interp = self elif isinstance(field, functions.Function): # eh, just add it as a local... # maybe the whole local/vars thinking needs to change... # and we should only have ONE map TODO field.name = field_name scope.add_local(field_name, field) elif field_name is not None: added_child = False # by this point, structs are already instantiated (they need to be # in order to set the new context) if not isinstance(field, fields.Field): if issubclass(field, fields.NumberBase): # use the default bitfield direction if self._bitfield_direction is self.BITFIELD_DIR_DEFAULT: bitfield_left_right = True if field.endian == fields.BIG_ENDIAN else False else: bitfield_left_right = (self._bitfield_direction is self.BITFIELD_DIR_LEFT_RIGHT) field = field( stream, bitsize=bitsize, metadata_processor=metadata_processor, bitfield_rw=bitfield_rw, bitfield_padded=self._padded_bitfield, bitfield_left_right=bitfield_left_right ) # TODO # for now if there's a struct inside of a union that is being # parsed when there's an error, the user will lose information # about how far the parsing got. Here we are explicitly checking for # adding structs and unions to a parent union. elif (issubclass(field, fields.Struct) or issubclass(field, fields.Union)) \ and not isinstance(ctxt, fields.Union) \ and hasattr(field, "_pfp__init"): # this is so that we can have all nested structs added to # the root DOM, even if there's an error in parsing the data. # If we didn't do this, any errors parsing the data would cause # the new struct to not be added to its parent, and the user would # not be able to see how far the script got field = field(stream, metadata_processor=metadata_processor, do_init=False) field._pfp__interp = self field_res = ctxt._pfp__add_child(field_name, field, stream) # when adding a new field to a struct/union/fileast, add it to the # root of the ctxt's scope so that it doesn't get lost by being declared # from within a function scope.add_var(field_name, field_res, root=True) field_res._pfp__interp = self field._pfp__init(stream) added_child = True else: field = field(stream, metadata_processor=metadata_processor) if not added_child: field._pfp__interp = self field_res = ctxt._pfp__add_child(field_name, field, stream) field_res._pfp__interp = self # when adding a new field to a struct/union/fileast, add it to the # root of the ctxt's scope so that it doesn't get lost by being declared # from within a function scope.add_var(field_name, field_res, root=True) # this shouldn't be used elsewhere, but should still be explicit with # this flag added_child = True # enums will get here. If there is no name, then no # field is being declared (but the enum values _will_ # get defined). E.g.: # enum <uchar blah { # BLAH1, # BLAH2, # BLAH3 # }; elif field_name is None: pass return field
Handle metadata for the node def _handle_metadata(self, node, scope, ctxt, stream): """Handle metadata for the node """ self._dlog("handling node metadata {}".format(node.metadata.keyvals)) keyvals = node.metadata.keyvals metadata_info = [] if "watch" in node.metadata.keyvals or "update" in keyvals: metadata_info.append( self._handle_watch_metadata(node, scope, ctxt, stream) ) if "packtype" in node.metadata.keyvals or "packer" in keyvals: metadata_info.append( self._handle_packed_metadata(node, scope, ctxt, stream) ) return metadata_info
Handle watch vars for fields def _handle_watch_metadata(self, node, scope, ctxt, stream): """Handle watch vars for fields """ keyvals = node.metadata.keyvals if "watch" not in keyvals: raise errors.PfpError("Packed fields require a packer function set") if "update" not in keyvals: raise errors.PfpError("Packed fields require a packer function set") watch_field_name = keyvals["watch"] update_func_name = keyvals["update"] watch_fields = list(map(lambda x: self.eval(x.strip()), watch_field_name.split(";"))) update_func = scope.get_id(update_func_name) return { "type": "watch", "watch_fields": watch_fields, "update_func": update_func, "func_call_info": (ctxt, scope, stream, self, self._coord) }
Handle packed metadata def _handle_packed_metadata(self, node, scope, ctxt, stream): """Handle packed metadata """ keyvals = node.metadata.keyvals if "packer" not in keyvals and ("pack" not in keyvals or "unpack" not in keyvals): raise errors.PfpError("Packed fields require a packer function to be set or pack and unpack functions to be set") if "packtype" not in keyvals: raise errors.PfpError("Packed fields require a packtype to be set") args_ = {} if "packer" in keyvals: packer_func_name = keyvals["packer"] packer_func = scope.get_id(packer_func_name) args_["packer"] = packer_func elif "pack" in keyvals and "unpack" in keyvals: pack_func = scope.get_id(keyvals["pack"]) unpack_func = scope.get_id(keyvals["unpack"]) args_["pack"] = pack_func args_["unpack"] = unpack_func packtype_cls_name = keyvals["packtype"] packtype_cls = scope.get_type(packtype_cls_name) args_["pack_type"] = packtype_cls args_["type"] = "packed" args_["func_call_info"] = (ctxt, scope, stream, self, self._coord) return args_
TODO: Docstring for _handle_byref_decl. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_byref_decl(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_byref_decl. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling byref decl") field = self._handle_node(node.type.type, scope, ctxt, stream) # this will not really be used (maybe except for introspection) # with byref function params # see issue #35 - we need to wrap the field cls so that the byref # doesn't permanently stay on the class field = functions.ParamClsWrapper(field) field.byref = True return field
TODO: Docstring for _handle_type_decl. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_type_decl(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_type_decl. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling type decl") decl = self._handle_node(node.type, scope, ctxt, stream) return decl
TODO: Docstring for _handle_struct_ref. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_struct_ref(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_struct_ref. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling struct ref") # name # field struct = self._handle_node(node.name, scope, ctxt, stream) try: sub_field = getattr(struct, node.field.name) except AttributeError as e: # should be able to access implicit array items by index OR # access the last one's members directly without index # # E.g.: # # local int total_length = 0; # while(!FEof()) { # HEADER header; # total_length += header.length; # } if isinstance(struct, fields.Array) and struct.implicit: last_item = struct[-1] sub_field = getattr(last_item, node.field.name) else: raise return sub_field
TODO: Docstring for _handle_union. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_union(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_union. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling union") union_cls = StructUnionDef("union", self, node) return union_cls
Handle InitList nodes (e.g. when initializing a struct) :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_init_list(self, node, scope, ctxt, stream): """Handle InitList nodes (e.g. when initializing a struct) :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling init list") res = [] for _,init_child in node.children(): init_field = self._handle_node(init_child, scope, ctxt, stream) res.append(init_field) return res
TODO: Docstring for _handle_struct_call_type_decl. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_struct_call_type_decl(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_struct_call_type_decl. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling struct with parameters") struct_cls = self._handle_node(node.type, scope, ctxt, stream) struct_args = self._handle_node(node.args, scope, ctxt, stream) res = StructDeclWithParams(scope, struct_cls, struct_args) return res
TODO: Docstring for _handle_struct. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_struct(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_struct. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling struct") if node.args is not None: for param in node.args.params: param.is_func_param = True # it's actually being defined if node.decls is not None: struct_cls = StructUnionDef("struct", self, node) if node.name is not None: scope.add_type_class(node.name, struct_cls) return struct_cls # it's declaring a struct field. E.g. # struct IFD subDir; else: return scope.get_type(node.name)
TODO: Docstring for _handle_identifier_type. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_identifier_type(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_identifier_type. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling identifier") cls = self._resolve_to_field_class(node.names, scope) return cls
TODO: Docstring for _handle_typedef. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_typedef(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_typedef. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ is_union_or_struct = (node.type.type.__class__ in [AST.Union, AST.Struct]) is_enum = (node.type.type.__class__ is AST.Enum) if is_union_or_struct: self._dlog("handling typedef struct/union '{}'".format(node.name)) scope.add_type_struct_or_union(node.name, self, node.type.type) elif is_enum: enum_cls = self._handle_node(node.type, scope, ctxt, stream) scope.add_type_class(node.name, enum_cls) elif isinstance(node.type, AST.ArrayDecl): # this does not parse data, just creates the ArrayDecl class array_cls = self._handle_node(node.type, scope, ctxt, stream) scope.add_type_class(node.name, array_cls) else: names = node.type.type.names self._dlog("handling typedef '{}' ({})".format(node.name, names)) # don't actually handle the TypeDecl and Identifier nodes, # just directly add the types. Example structure: # # Typedef: BLAH, [], ['typedef'] # TypeDecl: BLAH, [] # IdentifierType: ['unsigned', 'char'] # scope.add_type(node.name, names)
Check for the hex def _str_to_int(self, string): """Check for the hex """ string = string.lower() if string.endswith("l"): string = string[:-1] if string.lower().startswith("0x"): # should always match match = re.match(r'0[xX]([a-fA-F0-9]+)', string) return int(match.group(1), 0x10) else: return int(string)
TODO: Docstring for _handle_constant. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_constant(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_constant. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling constant type {}".format(node.type)) switch = { "int": (self._str_to_int, self._choose_const_int_class), "long": (self._str_to_int, self._choose_const_int_class), # TODO this isn't quite right, but py010parser wouldn't have # parsed it if it wasn't correct... "float": (lambda x: float(x.lower().replace("f", "")), fields.Float), "double": (float, fields.Double), # cut out the quotes "char": (lambda x: ord(utils.string_escape(x[1:-1])), fields.Char), # TODO should this be unicode?? will probably bite me later... # cut out the quotes "string": (lambda x: str(utils.string_escape(x[1:-1])), fields.String) } if node.type in switch: #return switch[node.type](node.value) conversion,field_cls = switch[node.type] val = conversion(node.value) if hasattr(field_cls, "__call__") and not type(field_cls) is type: field_cls = field_cls(val) field = field_cls() field._pfp__set_value(val) return field raise UnsupportedConstantType(node.coord, node.type)
TODO: Docstring for _handle_binary_op. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_binary_op(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_binary_op. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling binary operation {}".format(node.op)) switch = { "+": lambda x,y: x+y, "-": lambda x,y: x-y, "*": lambda x,y: x*y, "/": lambda x,y: x/y, "|": lambda x,y: x|y, "^": lambda x,y: x^y, "&": lambda x,y: x&y, "%": lambda x,y: x%y, ">": lambda x,y: x>y, "<": lambda x,y: x<y, "||": lambda x,y: x or y, ">=": lambda x,y: x>=y, "<=": lambda x,y: x<=y, "==": lambda x,y: x == y, "!=": lambda x,y: x != y, "&&": lambda x,y: x and y, ">>": lambda x,y: x >> y, "<<": lambda x,y: x << y, } left_val = self._handle_node(node.left, scope, ctxt, stream) right_val = self._handle_node(node.right, scope, ctxt, stream) if node.op not in switch: raise errors.UnsupportedBinaryOperator(node.coord, node.op) res = switch[node.op](left_val, right_val) if type(res) is bool: new_res = fields.Int() if res: new_res._pfp__set_value(1) else: new_res._pfp__set_value(0) res = new_res return res
TODO: Docstring for _handle_unary_op. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_unary_op(self, node, scope, ctxt, stream): """TODO: Docstring for _handle_unary_op. :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling unary op {}".format(node.op)) special_switch = { "parentof" : self._handle_parentof, "exists" : self._handle_exists, "function_exists" : self._handle_function_exists, "p++" : self._handle_post_plus_plus, "p--" : self._handle_post_minus_minus, } switch = { # for ++i and --i "++": lambda x,v: x.__iadd__(1), "--": lambda x,v: x.__isub__(1), "~": lambda x,v: ~x, "!": lambda x,v: not x, "-": lambda x,v: -x, "sizeof": lambda x,v: (fields.UInt64()+x._pfp__width()), "startof": lambda x,v: (fields.UInt64()+x._pfp__offset), } if node.op not in switch and node.op not in special_switch: raise errors.UnsupportedUnaryOperator(node.coord, node.op) if node.op in special_switch: return special_switch[node.op](node, scope, ctxt, stream) field = self._handle_node(node.expr, scope, ctxt, stream) if type(field) is type: field = field() res = switch[node.op](field, 1) if type(res) is bool: new_res = field.__class__() new_res._pfp__set_value(1 if res == True else 0) res = new_res return res
Handle the parentof unary operator :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_parentof(self, node, scope, ctxt, stream): """Handle the parentof unary operator :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ # if someone does something like parentof(this).blah, # we'll end up with a StructRef instead of an ID ref # for node.expr, but we'll also end up with a structref # if the user does parentof(a.b.c)... # # TODO how to differentiate between the two?? # # the proper way would be to do (parentof(a.b.c)).a or # (parentof a.b.c).a field = self._handle_node(node.expr, scope, ctxt, stream) parent = field._pfp__parent return parent
Handle the exists unary operator :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_exists(self, node, scope, ctxt, stream): """Handle the exists unary operator :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ res = fields.Int() try: self._handle_node(node.expr, scope, ctxt, stream) res._pfp__set_value(1) except AttributeError: res._pfp__set_value(0) return res
Handle the function_exists unary operator :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_function_exists(self, node, scope, ctxt, stream): """Handle the function_exists unary operator :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ res = fields.Int() try: func = self._handle_node(node.expr, scope, ctxt, stream) if isinstance(func, functions.BaseFunction): res._pfp__set_value(1) else: res._pfp__set_value(0) except errors.UnresolvedID: res._pfp__set_value(0) return res
Handle an ID node (return a field object for the ID) :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_id(self, node, scope, ctxt, stream): """Handle an ID node (return a field object for the ID) :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ if node.name == "__root": return self._root if node.name == "__this" or node.name == "this": return ctxt self._dlog("handling id {}".format(node.name)) field = scope.get_id(node.name) is_lazy = getattr(node, "is_lazy", False) if field is None and not is_lazy: raise errors.UnresolvedID(node.coord, node.name) elif is_lazy: return LazyField(node.name, scope) return field
Handle assignment nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_assignment(self, node, scope, ctxt, stream): """Handle assignment nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ def add_op(x,y): x += y def sub_op(x,y): x -= y def div_op(x,y): x /= y def mod_op(x,y): x %= y def mul_op(x,y): x *= y def xor_op(x,y): x ^= y def and_op(x,y): x &= y def or_op(x,y): x |= y def lshift_op(x,y): x <<= y def rshift_op(x,y): x >>= y def assign_op(x,y): x._pfp__set_value(y) switch = { "+=" : add_op, "-=" : sub_op, "/=" : div_op, "%=" : mod_op, "*=" : mul_op, "^=" : xor_op, "&=" : and_op, "|=" : or_op, "<<=" : lshift_op, ">>=" : rshift_op, "=" : assign_op } self._dlog("handling assignment") field = self._handle_node(node.lvalue, scope, ctxt, stream) self._dlog("field = {}".format(field)) value = self._handle_node(node.rvalue, scope, ctxt, stream) if node.op is None: self._dlog("value = {}".format(value)) field._pfp__set_value(value) else: self._dlog("value {}= {}".format(node.op, value)) if node.op not in switch: raise errors.UnsupportedAssignmentOperator(node.coord, node.op) switch[node.op](field, value)
Handle FuncDef nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_func_def(self, node, scope, ctxt, stream): """Handle FuncDef nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling function definition") func = self._handle_node(node.decl, scope, ctxt, stream) func.body = node.body
Handle ParamList nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_param_list(self, node, scope, ctxt, stream): """Handle ParamList nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling param list") # params should be a list of tuples: # [(<name>, <field_class>), ...] params = [] for param in node.params: self._mark_id_as_lazy(param) param_info = self._handle_node(param, scope, ctxt, stream) params.append(param_info) param_list = functions.ParamListDef(params, node.coord) return param_list
Handle FuncDecl nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_func_decl(self, node, scope, ctxt, stream): """Handle FuncDecl nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling func decl") if node.args is not None: # could just call _handle_param_list directly... for param in node.args.params: # see the check in _handle_decl for how this is kept from # being added to the local context/scope param.is_func_param = True params = self._handle_node(node.args, scope, ctxt, stream) else: params = functions.ParamListDef([], node.coord) func_type = self._handle_node(node.type, scope, ctxt, stream) func = functions.Function(func_type, params, scope) return func
Handle FuncCall nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_func_call(self, node, scope, ctxt, stream): """Handle FuncCall nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling function call to '{}'".format(node.name.name)) if node.args is None: func_args = [] else: func_args = self._handle_node(node.args, scope, ctxt, stream) func = self._handle_node(node.name, scope, ctxt, stream) return func.call(func_args, ctxt, scope, stream, self, node.coord)
Handle ExprList nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_expr_list(self, node, scope, ctxt, stream): """Handle ExprList nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling expression list") exprs = [ self._handle_node(expr, scope, ctxt, stream) for expr in node.exprs ] return exprs
Handle Compound nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_compound(self, node, scope, ctxt, stream): """Handle Compound nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling compound statement") #scope.push() try: for child in node.children(): self._handle_node(child, scope, ctxt, stream) # in case a return occurs, be sure to pop the scope # (returns are implemented by raising an exception) finally: #scope.pop() pass
Handle Return nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_return(self, node, scope, ctxt, stream): """Handle Return nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling return") if node.expr is None: ret_val = None else: ret_val = self._handle_node(node.expr, scope, ctxt, stream) self._dlog("return value = {}".format(ret_val)) raise errors.InterpReturn(ret_val)
Handle enum nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_enum(self, node, scope, ctxt, stream): """Handle enum nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling enum") if node.type is None: enum_cls = fields.Int else: enum_cls = self._handle_node(node.type, scope, ctxt, stream) enum_vals = {} curr_val = enum_cls() curr_val._pfp__value = -1 for enumerator in node.values.enumerators: if enumerator.value is not None: curr_val = self._handle_node(enumerator.value, scope, ctxt, stream) else: curr_val = curr_val + 1 curr_val._pfp__freeze() enum_vals[enumerator.name] = curr_val enum_vals[fields.PYVAL(curr_val)] = enumerator.name scope.add_local(enumerator.name, curr_val) if node.name is not None: enum_cls = EnumDef(node.name, enum_cls, enum_vals) scope.add_type_class(node.name, enum_cls) else: enum_cls = EnumDef("enum_" + enum_cls.__name__, enum_cls, enum_vals) # don't add to scope if we don't have a name return enum_cls
Handle ArrayDecl nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_array_decl(self, node, scope, ctxt, stream): """Handle ArrayDecl nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling array declaration '{}'".format(node.type.declname)) if node.dim is None: # will be used array_size = None else: array_size = self._handle_node(node.dim, scope, ctxt, stream) self._dlog("array size = {}".format(array_size)) # TODO node.dim_quals # node.type field_cls = self._handle_node(node.type, scope, ctxt, stream) self._dlog("field class = {}".format(field_cls)) array = ArrayDecl(field_cls, array_size) #array = fields.Array(array_size, field_cls) array._pfp__name = node.type.declname #array._pfp__parse(stream) return array
Handle ArrayRef nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_array_ref(self, node, scope, ctxt, stream): """Handle ArrayRef nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ ary = self._handle_node(node.name, scope, ctxt, stream) subscript = self._handle_node(node.subscript, scope, ctxt, stream) return ary[fields.PYVAL(subscript)]
Handle If nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_if(self, node, scope, ctxt, stream): """Handle If nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling if/ternary_op") cond = self._handle_node(node.cond, scope, ctxt, stream) if cond: # there should always be an iftrue return self._handle_node(node.iftrue, scope, ctxt, stream) else: if node.iffalse is not None: return self._handle_node(node.iffalse, scope, ctxt, stream)
Handle For nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_for(self, node, scope, ctxt, stream): """Handle For nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling for") if node.init is not None: # perform the init self._handle_node(node.init, scope, ctxt, stream) while node.cond is None or self._handle_node(node.cond, scope, ctxt, stream): if node.stmt is not None: try: # do the for body self._handle_node(node.stmt, scope, ctxt, stream) except errors.InterpBreak as e: break # we still need to interpret the "next" statement, # so just pass except errors.InterpContinue as e: pass if node.next is not None: # do the next statement self._handle_node(node.next, scope, ctxt, stream)
Handle break node :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_while(self, node, scope, ctxt, stream): """Handle break node :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling while") while node.cond is None or self._handle_node(node.cond, scope, ctxt, stream): if node.stmt is not None: try: self._handle_node(node.stmt, scope, ctxt, stream) except errors.InterpBreak as e: break except errors.InterpContinue as e: pass
Handle break node :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_switch(self, node, scope, ctxt, stream): """Handle break node :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ def exec_case(idx, cases): # keep executing cases until a break is found, # or they've all been executed for case in cases[idx:]: stmts = case.stmts try: for stmt in stmts: self._handle_node(stmt, scope, ctxt, stream) except errors.InterpBreak as e: break def get_stmts(stmts, res=None): if res is None: res = [] stmts = self._flatten_list(stmts) for stmt in stmts: if isinstance(stmt, tuple): stmt = stmt[1] res.append(stmt) if stmt.__class__ in [AST.Case, AST.Default]: get_stmts(stmt.stmts, res) return res def get_cases(nodes, acc=None): cases = [] stmts = get_stmts(nodes) for stmt in stmts: if stmt.__class__ in [AST.Case, AST.Default]: cases.append(stmt) stmt.stmts = [] else: cases[-1].stmts.append(stmt) return cases cond = self._handle_node(node.cond, scope, ctxt, stream) default_idx = None found_match = False cases = getattr(node, "pfp_cases", None) if cases is None: cases = get_cases(node.stmt.children()) node.pfp_cases = cases for idx,child in enumerate(cases): if child.__class__ == AST.Default: default_idx = idx continue elif child.__class__ == AST.Case: expr = self._handle_node(child.expr, scope, ctxt, stream) if expr == cond: found_match = True exec_case(idx, cases) break if default_idx is not None and not found_match: exec_case(default_idx, cases)
Handle break node :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_break(self, node, scope, ctxt, stream): """Handle break node :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling break") raise errors.InterpBreak()
Handle continue node :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_continue(self, node, scope, ctxt, stream): """Handle continue node :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling continue") raise errors.InterpContinue()
Handle For nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO def _handle_decl_list(self, node, scope, ctxt, stream): """Handle For nodes :node: TODO :scope: TODO :ctxt: TODO :stream: TODO :returns: TODO """ self._dlog("handling decl list") # just handle each declaration for decl in node.decls: self._handle_node(decl, scope, ctxt, stream)
TODO: Docstring for _create_scope. :returns: TODO def _create_scope(self): """TODO: Docstring for _create_scope. :returns: TODO """ res = Scope(self._log) for func_name,native_func in six.iteritems(self._natives): res.add_local(func_name, native_func) return res
Return the value of the node. It is expected to be either an AST.ID instance or a constant :node: TODO :returns: TODO def _get_value(self, node, scope, ctxt, stream): """Return the value of the node. It is expected to be either an AST.ID instance or a constant :node: TODO :returns: TODO """ res = self._handle_node(node, scope, ctxt, stream) if isinstance(res, fields.Field): return res._pfp__value # assume it's a constant else: return res
Resolve the names to a class in fields.py, resolving past typedefs, etc :names: TODO :scope: TODO :ctxt: TODO :returns: TODO def _resolve_to_field_class(self, names, scope): """Resolve the names to a class in fields.py, resolving past typedefs, etc :names: TODO :scope: TODO :ctxt: TODO :returns: TODO """ switch = { "char" : "Char", "int" : "Int", "long" : "Int", "int64" : "Int64", "uint64" : "UInt64", "short" : "Short", "double" : "Double", "float" : "Float", "void" : "Void", "string" : "String", "wstring" : "WString" } core = names[-1] if core not in switch: # will return a list of resolved names type_info = scope.get_type(core) if type(type_info) is type and issubclass(type_info, fields.Field): return type_info resolved_names = type_info if resolved_names is None: raise errors.UnresolvedType(self._coord, " ".join(names), " ") if resolved_names[-1] not in switch: raise errors.UnresolvedType(self._coord, " ".join(names), " ".join(resolved_names)) names = copy.copy(names) names.pop() names += resolved_names if len(names) >= 2 and names[-1] == names[-2] and names[-1] == "long": res = "Int64" else: res = switch[names[-1]] if names[-1] in ["char", "short", "int", "long"] and "unsigned" in names[:-1]: res = "U" + res cls = getattr(fields, res) return cls
Convert the bit list into bytes. (Assumes bits is a list whose length is a multiple of 8) def bits_to_bytes(bits): """Convert the bit list into bytes. (Assumes bits is a list whose length is a multiple of 8) """ if len(bits) % 8 != 0: raise Exception("num bits must be multiple of 8") res = "" for x in six.moves.range(0, len(bits), 8): byte_bits = bits[x:x+8] byte_val = int(''.join(map(str, byte_bits)), 2) res += chr(byte_val) return utils.binary(res)
Convert bytes to a list of bits def bytes_to_bits(bytes_): """Convert bytes to a list of bits """ res = [] for x in bytes_: if not isinstance(x, int): x = ord(x) res += byte_to_bits(x) return res
Return if the stream has reached EOF or not without discarding any unflushed bits :returns: True/False def is_eof(self): """Return if the stream has reached EOF or not without discarding any unflushed bits :returns: True/False """ pos = self._stream.tell() byte = self._stream.read(1) self._stream.seek(pos, 0) return utils.binary(byte) == utils.binary("")
Close the stream def close(self): """Close the stream """ self.closed = True self._flush_bits_to_stream() self._stream.close()
Read ``num`` number of bytes from the stream. Note that this will automatically resets/ends the current bit-reading if it does not end on an even byte AND ``self.padded`` is True. If ``self.padded`` is True, then the entire stream is treated as a bitstream. :num: number of bytes to read :returns: the read bytes, or empty string if EOF has been reached def read(self, num): """Read ``num`` number of bytes from the stream. Note that this will automatically resets/ends the current bit-reading if it does not end on an even byte AND ``self.padded`` is True. If ``self.padded`` is True, then the entire stream is treated as a bitstream. :num: number of bytes to read :returns: the read bytes, or empty string if EOF has been reached """ start_pos = self.tell() if self.padded: # we toss out any uneven bytes self._bits.clear() res = utils.binary(self._stream.read(num)) else: bits = self.read_bits(num * 8) res = bits_to_bytes(bits) res = utils.binary(res) end_pos = self.tell() self._update_consumed_ranges(start_pos, end_pos) return res
Read ``num`` number of bits from the stream :num: number of bits to read :returns: a list of ``num`` bits, or an empty list if EOF has been reached def read_bits(self, num): """Read ``num`` number of bits from the stream :num: number of bits to read :returns: a list of ``num`` bits, or an empty list if EOF has been reached """ if num > len(self._bits): needed = num - len(self._bits) num_bytes = int(math.ceil(needed / 8.0)) read_bytes = self._stream.read(num_bytes) for bit in bytes_to_bits(read_bytes): self._bits.append(bit) res = [] while len(res) < num and len(self._bits) > 0: res.append(self._bits.popleft()) return res
Write data to the stream :data: the data to write to the stream :returns: None def write(self, data): """Write data to the stream :data: the data to write to the stream :returns: None """ if self.padded: # flush out any remaining bits first if len(self._bits) > 0: self._flush_bits_to_stream() self._stream.write(data) else: # nothing to do here if len(data) == 0: return bits = bytes_to_bits(data) self.write_bits(bits)
Write the bits to the stream. Add the bits to the existing unflushed bits and write complete bytes to the stream. def write_bits(self, bits): """Write the bits to the stream. Add the bits to the existing unflushed bits and write complete bytes to the stream. """ for bit in bits: self._bits.append(bit) while len(self._bits) >= 8: byte_bits = [self._bits.popleft() for x in six.moves.range(8)] byte = bits_to_bytes(byte_bits) self._stream.write(byte)
Return the current position in the stream (ignoring bit position) :returns: int for the position in the stream def tell(self): """Return the current position in the stream (ignoring bit position) :returns: int for the position in the stream """ res = self._stream.tell() if len(self._bits) > 0: res -= 1 return res
Seek to the specified position in the stream with seek_type. Unflushed bits will be discarded in the case of a seek. The stream will also keep track of which bytes have and have not been consumed so that the dom will capture all of the bytes in the stream. :pos: offset :seek_type: direction :returns: TODO def seek(self, pos, seek_type=0): """Seek to the specified position in the stream with seek_type. Unflushed bits will be discarded in the case of a seek. The stream will also keep track of which bytes have and have not been consumed so that the dom will capture all of the bytes in the stream. :pos: offset :seek_type: direction :returns: TODO """ self._bits.clear() return self._stream.seek(pos, seek_type)
Return the size of the stream, or -1 if it cannot be determined. def size(self): """Return the size of the stream, or -1 if it cannot be determined. """ pos = self._stream.tell() # seek to the end of the stream self._stream.seek(0,2) size = self._stream.tell() self._stream.seek(pos, 0) return size
Return an IntervalTree of unconsumed ranges, of the format (start, end] with the end value not being included def unconsumed_ranges(self): """Return an IntervalTree of unconsumed ranges, of the format (start, end] with the end value not being included """ res = IntervalTree() prev = None # normal iteration is not in a predictable order ranges = sorted([x for x in self.range_set], key=lambda x: x.begin) for rng in ranges: if prev is None: prev = rng continue res.add(Interval(prev.end, rng.begin)) prev = rng # means we've seeked past the end if len(self.range_set[self.tell()]) != 1: res.add(Interval(prev.end, self.tell())) return res
Update the ``self.consumed_ranges`` array with which byte ranges have been consecutively consumed. def _update_consumed_ranges(self, start_pos, end_pos): """Update the ``self.consumed_ranges`` array with which byte ranges have been consecutively consumed. """ self.range_set.add(Interval(start_pos, end_pos+1)) self.range_set.merge_overlaps()
Flush the bits to the stream. This is used when a few bits have been read and ``self._bits`` contains unconsumed/ flushed bits when data is to be written to the stream def _flush_bits_to_stream(self): """Flush the bits to the stream. This is used when a few bits have been read and ``self._bits`` contains unconsumed/ flushed bits when data is to be written to the stream """ if len(self._bits) == 0: return 0 bits = list(self._bits) diff = 8 - (len(bits) % 8) padding = [0] * diff bits = bits + padding self._stream.write(bits_to_bytes(bits)) self._bits.clear()
ensure that fields are present in markdown file def _validate_markdown(self, expfile): '''ensure that fields are present in markdown file''' try: import yaml except: bot.error('Python yaml is required for testing yml/markdown files.') sys.exit(1) self.metadata = {} uid = os.path.basename(expfile).strip('.md') if os.path.exists(expfile): with open(expfile, "r") as stream: docs = yaml.load_all(stream) for doc in docs: if isinstance(doc,dict): for k,v in doc.items(): print('%s: %s' %(k,v)) self.metadata[k] = v self.metadata['uid'] = uid fields = ['github', 'preview', 'name', 'layout', 'tags', 'uid', 'maintainer'] # Tests for all fields for field in fields: if field not in self.metadata: return False if self.metadata[field] in ['',None]: return False if 'github' not in self.metadata['github']: return notvalid('%s: not a valid github repository' % name) if not isinstance(self.metadata['tags'],list): return notvalid('%s: tags must be a list' % name) if not re.search("(\w+://)(.+@)*([\w\d\.]+)(:[\d]+){0,1}/*(.*)", self.metadata['github']): return notvalid('%s is not a valid URL.' %(self.metadata['github'])) return True
return all checks for required variables before returning to desired view Parameters ========== template: the html template to render do_redirect: if True, perform a redirect and not render context: dictionary of context variables to pass to render_template next: a pre-defined next experiment, will calculate if None quiet: decrease verbosity def perform_checks(template, do_redirect=False, context=None, next=None, quiet=False): '''return all checks for required variables before returning to desired view Parameters ========== template: the html template to render do_redirect: if True, perform a redirect and not render context: dictionary of context variables to pass to render_template next: a pre-defined next experiment, will calculate if None quiet: decrease verbosity ''' from expfactory.server import app username = session.get('username') subid = session.get('subid') # If redirect, "last" is currently active (about to start) # If render, "last" is last completed / active experiment (just finished) last = session.get('exp_id') if next is None: next = app.get_next(session) session['exp_id'] = next # Headless mode requires token if "token" not in session and app.headless is True: flash('A token is required for these experiments.') return redirect('/') # Update the user / log if quiet is False: app.logger.info("[router] %s --> %s [subid] %s [user] %s" %(last, next, subid, username)) if username is None and app.headless is False: flash('You must start a session before doing experiments.') return redirect('/') if subid is None: flash('You must have a participant identifier before doing experiments') return redirect('/') if next is None: flash('Congratulations, you have finished the battery!') return redirect('/finish') if do_redirect is True: app.logger.debug('Redirecting to %s' %template) return redirect(template) if context is not None and isinstance(context, dict): app.logger.debug('Rendering %s' %template) return render_template(template, **context) return render_template(template)