qemu/scripts/tracetool/__init__.py
Stefan Hajnoczi b3ef0ade57 tracetool: avoid str.rpartition() Python 2.5 function
The str.rpartition() function is related to str.split() and is used for
splitting strings.  It was introduced in Python 2.5 and therefore cannot
be used in tracetool as Python 2.4 compatibility is required.

Replace the code using str.rsplit().

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
2012-05-01 20:15:28 +01:00

275 lines
7.4 KiB
Python

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
Machinery for generating tracing-related intermediate files.
"""
__author__ = "Lluís Vilanova <vilanova@ac.upc.edu>"
__copyright__ = "Copyright 2012, 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
@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))
@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)
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")
mformat = format.replace("-", "_")
if not tracetool.format.exists(mformat):
raise TracetoolError("unknown format: %s" % format)
backend = str(backend)
if len(backend) is 0:
raise TracetoolError("backend not set")
mbackend = backend.replace("-", "_")
if not tracetool.backend.exists(mbackend):
raise TracetoolError("unknown backend: %s" % backend)
if not tracetool.backend.compatible(mbackend, mformat):
raise TracetoolError("backend '%s' not compatible with format '%s'" %
(backend, format))
import tracetool.backend.dtrace
tracetool.backend.dtrace.BINARY = binary
tracetool.backend.dtrace.PROBEPREFIX = probe_prefix
events = _read_events(fevents)
if backend == "nop":
( e.properies.add("disable") for e in events )
tracetool.format.generate_begin(mformat, events)
tracetool.backend.generate("nop", format,
[ e
for e in events
if "disable" in e.properties ])
tracetool.backend.generate(backend, format,
[ e
for e in events
if "disable" not in e.properties ])
tracetool.format.generate_end(mformat, events)