| #!/usr/bin/env python |
| # -*- coding: utf-8 -*- |
| |
| """ |
| Machinery for generating tracing-related intermediate files. |
| """ |
| |
| __author__ = "Lluís Vilanova <vilanova@ac.upc.edu>" |
| __copyright__ = "Copyright 2012-2014, Lluís Vilanova <vilanova@ac.upc.edu>" |
| __license__ = "GPL version 2 or (at your option) any later version" |
| |
| __maintainer__ = "Stefan Hajnoczi" |
| __email__ = "stefanha@linux.vnet.ibm.com" |
| |
| |
| import re |
| import sys |
| |
| import tracetool.format |
| import tracetool.backend |
| |
| |
| def error_write(*lines): |
| """Write a set of error lines.""" |
| sys.stderr.writelines("\n".join(lines) + "\n") |
| |
| def error(*lines): |
| """Write a set of error lines and exit.""" |
| error_write(*lines) |
| sys.exit(1) |
| |
| |
| def out(*lines, **kwargs): |
| """Write a set of output lines. |
| |
| You can use kwargs as a shorthand for mapping variables when formating all |
| the strings in lines. |
| """ |
| lines = [ l % kwargs for l in lines ] |
| sys.stdout.writelines("\n".join(lines) + "\n") |
| |
| |
| class Arguments: |
| """Event arguments description.""" |
| |
| def __init__(self, args): |
| """ |
| Parameters |
| ---------- |
| args : |
| List of (type, name) tuples. |
| """ |
| self._args = args |
| |
| def copy(self): |
| """Create a new copy.""" |
| return Arguments(list(self._args)) |
| |
| @staticmethod |
| def build(arg_str): |
| """Build and Arguments instance from an argument string. |
| |
| Parameters |
| ---------- |
| arg_str : str |
| String describing the event arguments. |
| """ |
| res = [] |
| for arg in arg_str.split(","): |
| arg = arg.strip() |
| if arg == 'void': |
| continue |
| |
| if '*' in arg: |
| arg_type, identifier = arg.rsplit('*', 1) |
| arg_type += '*' |
| identifier = identifier.strip() |
| else: |
| arg_type, identifier = arg.rsplit(None, 1) |
| |
| res.append((arg_type, identifier)) |
| return Arguments(res) |
| |
| def __iter__(self): |
| """Iterate over the (type, name) pairs.""" |
| return iter(self._args) |
| |
| def __len__(self): |
| """Number of arguments.""" |
| return len(self._args) |
| |
| def __str__(self): |
| """String suitable for declaring function arguments.""" |
| if len(self._args) == 0: |
| return "void" |
| else: |
| return ", ".join([ " ".join([t, n]) for t,n in self._args ]) |
| |
| def __repr__(self): |
| """Evaluable string representation for this object.""" |
| return "Arguments(\"%s\")" % str(self) |
| |
| def names(self): |
| """List of argument names.""" |
| return [ name for _, name in self._args ] |
| |
| def types(self): |
| """List of argument types.""" |
| return [ type_ for type_, _ in self._args ] |
| |
| |
| class Event(object): |
| """Event description. |
| |
| Attributes |
| ---------- |
| name : str |
| The event name. |
| fmt : str |
| The event format string. |
| properties : set(str) |
| Properties of the event. |
| args : Arguments |
| The event arguments. |
| """ |
| |
| _CRE = re.compile("((?P<props>.*)\s+)?(?P<name>[^(\s]+)\((?P<args>[^)]*)\)\s*(?P<fmt>\".*)?") |
| |
| _VALID_PROPS = set(["disable"]) |
| |
| def __init__(self, name, props, fmt, args): |
| """ |
| Parameters |
| ---------- |
| name : string |
| Event name. |
| props : list of str |
| Property names. |
| fmt : str |
| Event printing format. |
| args : Arguments |
| Event arguments. |
| """ |
| self.name = name |
| self.properties = props |
| self.fmt = fmt |
| self.args = args |
| |
| unknown_props = set(self.properties) - self._VALID_PROPS |
| if len(unknown_props) > 0: |
| raise ValueError("Unknown properties: %s" |
| % ", ".join(unknown_props)) |
| |
| def copy(self): |
| """Create a new copy.""" |
| return Event(self.name, list(self.properties), self.fmt, |
| self.args.copy(), self) |
| |
| @staticmethod |
| def build(line_str): |
| """Build an Event instance from a string. |
| |
| Parameters |
| ---------- |
| line_str : str |
| Line describing the event. |
| """ |
| m = Event._CRE.match(line_str) |
| assert m is not None |
| groups = m.groupdict('') |
| |
| name = groups["name"] |
| props = groups["props"].split() |
| fmt = groups["fmt"] |
| args = Arguments.build(groups["args"]) |
| |
| return Event(name, props, fmt, args) |
| |
| def __repr__(self): |
| """Evaluable string representation for this object.""" |
| return "Event('%s %s(%s) %s')" % (" ".join(self.properties), |
| self.name, |
| self.args, |
| self.fmt) |
| |
| QEMU_TRACE = "trace_%(name)s" |
| |
| def api(self, fmt=None): |
| if fmt is None: |
| fmt = Event.QEMU_TRACE |
| return fmt % {"name": self.name} |
| |
| |
| def _read_events(fobj): |
| res = [] |
| for line in fobj: |
| if not line.strip(): |
| continue |
| if line.lstrip().startswith('#'): |
| continue |
| res.append(Event.build(line)) |
| return res |
| |
| |
| class TracetoolError (Exception): |
| """Exception for calls to generate.""" |
| pass |
| |
| |
| def try_import(mod_name, attr_name=None, attr_default=None): |
| """Try to import a module and get an attribute from it. |
| |
| Parameters |
| ---------- |
| mod_name : str |
| Module name. |
| attr_name : str, optional |
| Name of an attribute in the module. |
| attr_default : optional |
| Default value if the attribute does not exist in the module. |
| |
| Returns |
| ------- |
| A pair indicating whether the module could be imported and the module or |
| object or attribute value. |
| """ |
| try: |
| module = __import__(mod_name, globals(), locals(), ["__package__"]) |
| if attr_name is None: |
| return True, module |
| return True, getattr(module, str(attr_name), attr_default) |
| except ImportError: |
| return False, None |
| |
| |
| def generate(fevents, format, backend, |
| binary=None, probe_prefix=None): |
| """Generate the output for the given (format, backend) pair. |
| |
| Parameters |
| ---------- |
| fevents : file |
| Event description file. |
| format : str |
| Output format name. |
| backend : str |
| Output backend name. |
| binary : str or None |
| See tracetool.backend.dtrace.BINARY. |
| probe_prefix : str or None |
| See tracetool.backend.dtrace.PROBEPREFIX. |
| """ |
| # fix strange python error (UnboundLocalError tracetool) |
| import tracetool |
| |
| format = str(format) |
| if len(format) is 0: |
| raise TracetoolError("format not set") |
| if not tracetool.format.exists(format): |
| raise TracetoolError("unknown format: %s" % format) |
| format = format.replace("-", "_") |
| |
| backend = str(backend) |
| if len(backend) is 0: |
| raise TracetoolError("backend not set") |
| if not tracetool.backend.exists(backend): |
| raise TracetoolError("unknown backend: %s" % backend) |
| backend = backend.replace("-", "_") |
| backend = tracetool.backend.Wrapper(backend, format) |
| |
| import tracetool.backend.dtrace |
| tracetool.backend.dtrace.BINARY = binary |
| tracetool.backend.dtrace.PROBEPREFIX = probe_prefix |
| |
| events = _read_events(fevents) |
| |
| tracetool.format.generate(events, format, backend) |