blob: eccf5524f32fb69f9d47bed76ee6978101a873ad [file] [log] [blame]
#!/usr/bin/env python
# -*- coding: utf-8 -*-
Machinery for generating tracing-related intermediate files.
__author__ = "Lluís Vilanova <>"
__copyright__ = "Copyright 2012-2014, Lluís Vilanova <>"
__license__ = "GPL version 2 or (at your option) any later version"
__maintainer__ = "Stefan Hajnoczi"
__email__ = ""
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."""
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):
args :
List of (type, name) tuples.
self._args = args
def copy(self):
"""Create a new copy."""
return Arguments(list(self._args))
def build(arg_str):
"""Build and Arguments instance from an argument string.
arg_str : str
String describing the event arguments.
res = []
for arg in arg_str.split(","):
arg = arg.strip()
if arg == 'void':
if '*' in arg:
arg_type, identifier = arg.rsplit('*', 1)
arg_type += '*'
identifier = identifier.strip()
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"
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.
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):
name : string
Event name.
props : list of str
Property names.
fmt : str
Event printing format.
args : Arguments
Event arguments.
""" = name = props
self.fmt = fmt
self.args = args
unknown_props = set( - 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(, list(, self.fmt,
self.args.copy(), self)
def build(line_str):
"""Build an Event instance from a string.
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 =["args"])
return Event(name, props, fmt, args)
def __repr__(self):
"""Evaluable string representation for this object."""
return "Event('%s %s(%s) %s')" % (" ".join(,,
QEMU_TRACE = "trace_%(name)s"
def api(self, fmt=None):
if fmt is None:
fmt = Event.QEMU_TRACE
return fmt % {"name":}
def _read_events(fobj):
res = []
for line in fobj:
if not line.strip():
if line.lstrip().startswith('#'):
return res
class TracetoolError (Exception):
"""Exception for calls to generate."""
def try_import(mod_name, attr_name=None, attr_default=None):
"""Try to import a module and get an attribute from it.
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.
A pair indicating whether the module could be imported and the module or
object or attribute value.
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.
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)