| # -*- coding: utf-8 -*- | |
| """ | |
| Machinery for generating tracing-related intermediate files. | |
| """ | |
| __author__ = "Lluís Vilanova <vilanova@ac.upc.edu>" | |
| __copyright__ = "Copyright 2012-2017, Lluís Vilanova <vilanova@ac.upc.edu>" | |
| __license__ = "GPL version 2 or (at your option) any later version" | |
| __maintainer__ = "Stefan Hajnoczi" | |
| __email__ = "stefanha@redhat.com" | |
| import os | |
| import re | |
| import sys | |
| import weakref | |
| from pathlib import PurePath | |
| import tracetool.backend | |
| import tracetool.format | |
| 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) | |
| out_lineno = 1 | |
| out_filename = '<none>' | |
| out_fobj = sys.stdout | |
| def out_open(filename): | |
| global out_filename, out_fobj | |
| out_filename = posix_relpath(filename) | |
| out_fobj = open(filename, 'wt') | |
| def out(*lines, **kwargs): | |
| """Write a set of output lines. | |
| You can use kwargs as a shorthand for mapping variables when formatting all | |
| the strings in lines. | |
| The 'out_lineno' kwarg is automatically added to reflect the current output | |
| file line number. The 'out_next_lineno' kwarg is also automatically added | |
| with the next output line number. The 'out_filename' kwarg is automatically | |
| added with the output filename. | |
| """ | |
| global out_lineno | |
| output = [] | |
| for l in lines: | |
| kwargs['out_lineno'] = out_lineno | |
| kwargs['out_next_lineno'] = out_lineno + 1 | |
| kwargs['out_filename'] = out_filename | |
| output.append(l % kwargs) | |
| out_lineno += 1 | |
| out_fobj.writelines("\n".join(output) + "\n") | |
| # We only want to allow standard C types or fixed sized | |
| # integer types. We don't want QEMU specific types | |
| # as we can't assume trace backends can resolve all the | |
| # typedefs | |
| ALLOWED_TYPES = [ | |
| "int", | |
| "long", | |
| "short", | |
| "char", | |
| "bool", | |
| "unsigned", | |
| "signed", | |
| "int8_t", | |
| "uint8_t", | |
| "int16_t", | |
| "uint16_t", | |
| "int32_t", | |
| "uint32_t", | |
| "int64_t", | |
| "uint64_t", | |
| "void", | |
| "size_t", | |
| "ssize_t", | |
| "uintptr_t", | |
| "ptrdiff_t", | |
| ] | |
| def validate_type(name): | |
| bits = name.split(" ") | |
| for bit in bits: | |
| bit = re.sub(r"\*", "", bit) | |
| if bit == "": | |
| continue | |
| if bit == "const": | |
| continue | |
| if bit not in ALLOWED_TYPES: | |
| raise ValueError("Argument type '%s' is not allowed. " | |
| "Only standard C types and fixed size integer " | |
| "types should be used. struct, union, and " | |
| "other complex pointer types should be " | |
| "declared as 'void *'" % name) | |
| class Arguments: | |
| """Event arguments description.""" | |
| def __init__(self, args): | |
| """ | |
| Parameters | |
| ---------- | |
| args : | |
| List of (type, name) tuples or Arguments objects. | |
| """ | |
| self._args = [] | |
| for arg in args: | |
| if isinstance(arg, Arguments): | |
| self._args.extend(arg._args) | |
| else: | |
| self._args.append(arg) | |
| 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 not arg: | |
| raise ValueError("Empty argument (did you forget to use 'void'?)") | |
| 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) | |
| validate_type(arg_type) | |
| res.append((arg_type, identifier)) | |
| return Arguments(res) | |
| def __getitem__(self, index): | |
| if isinstance(index, slice): | |
| return Arguments(self._args[index]) | |
| else: | |
| return self._args[index] | |
| 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 ] | |
| def casted(self): | |
| """List of argument names casted to their type.""" | |
| return ["(%s)%s" % (type_, name) for type_, name 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. | |
| lineno : int | |
| The line number in the input file. | |
| filename : str | |
| The path to the input file. | |
| """ | |
| _CRE = re.compile(r"((?P<props>[\w\s]+)\s+)?" | |
| r"(?P<name>\w+)" | |
| r"\((?P<args>[^)]*)\)" | |
| r"\s*" | |
| r"(?:(?:(?P<fmt_trans>\".+),)?\s*(?P<fmt>\".+))?" | |
| r"\s*") | |
| _VALID_PROPS = set(["disable"]) | |
| def __init__(self, name, props, fmt, args, lineno, filename, orig=None, | |
| event_trans=None, event_exec=None): | |
| """ | |
| Parameters | |
| ---------- | |
| name : string | |
| Event name. | |
| props : list of str | |
| Property names. | |
| fmt : str, list of str | |
| Event printing format string(s). | |
| args : Arguments | |
| Event arguments. | |
| lineno : int | |
| The line number in the input file. | |
| filename : str | |
| The path to the input file. | |
| orig : Event or None | |
| Original Event before transformation/generation. | |
| event_trans : Event or None | |
| Generated translation-time event ("tcg" property). | |
| event_exec : Event or None | |
| Generated execution-time event ("tcg" property). | |
| """ | |
| self.name = name | |
| self.properties = props | |
| self.fmt = fmt | |
| self.args = args | |
| self.lineno = int(lineno) | |
| self.filename = str(filename) | |
| self.event_trans = event_trans | |
| self.event_exec = event_exec | |
| if len(args) > 10: | |
| raise ValueError("Event '%s' has more than maximum permitted " | |
| "argument count" % name) | |
| if orig is None: | |
| self.original = weakref.ref(self) | |
| else: | |
| self.original = orig | |
| unknown_props = set(self.properties) - self._VALID_PROPS | |
| if len(unknown_props) > 0: | |
| raise ValueError("Unknown properties: %s" | |
| % ", ".join(unknown_props)) | |
| assert isinstance(self.fmt, str) or len(self.fmt) == 2 | |
| def copy(self): | |
| """Create a new copy.""" | |
| return Event(self.name, list(self.properties), self.fmt, | |
| self.args.copy(), self.lineno, self.filename, | |
| self, self.event_trans, self.event_exec) | |
| @staticmethod | |
| def build(line_str, lineno, filename): | |
| """Build an Event instance from a string. | |
| Parameters | |
| ---------- | |
| line_str : str | |
| Line describing the event. | |
| lineno : int | |
| Line number in input file. | |
| filename : str | |
| Path to input file. | |
| """ | |
| m = Event._CRE.match(line_str) | |
| assert m is not None | |
| groups = m.groupdict('') | |
| name = groups["name"] | |
| props = groups["props"].split() | |
| fmt = groups["fmt"] | |
| fmt_trans = groups["fmt_trans"] | |
| if fmt.find("%m") != -1 or fmt_trans.find("%m") != -1: | |
| raise ValueError("Event format '%m' is forbidden, pass the error " | |
| "as an explicit trace argument") | |
| if fmt.endswith(r'\n"'): | |
| raise ValueError("Event format must not end with a newline " | |
| "character") | |
| if '\\n' in fmt: | |
| raise ValueError("Event format must not use new line character") | |
| if len(fmt_trans) > 0: | |
| fmt = [fmt_trans, fmt] | |
| args = Arguments.build(groups["args"]) | |
| return Event(name, props, fmt, args, lineno, posix_relpath(filename)) | |
| def __repr__(self): | |
| """Evaluable string representation for this object.""" | |
| if isinstance(self.fmt, str): | |
| fmt = self.fmt | |
| else: | |
| fmt = "%s, %s" % (self.fmt[0], self.fmt[1]) | |
| return "Event('%s %s(%s) %s')" % (" ".join(self.properties), | |
| self.name, | |
| self.args, | |
| fmt) | |
| # Star matching on PRI is dangerous as one might have multiple | |
| # arguments with that format, hence the non-greedy version of it. | |
| _FMT = re.compile(r"(%[\d\.]*\w+|%.*?PRI\S+)") | |
| def formats(self): | |
| """List conversion specifiers in the argument print format string.""" | |
| assert not isinstance(self.fmt, list) | |
| return self._FMT.findall(self.fmt) | |
| QEMU_TRACE = "trace_%(name)s" | |
| QEMU_TRACE_NOCHECK = "_nocheck__" + QEMU_TRACE | |
| QEMU_TRACE_TCG = QEMU_TRACE + "_tcg" | |
| QEMU_DSTATE = "_TRACE_%(NAME)s_DSTATE" | |
| QEMU_BACKEND_DSTATE = "TRACE_%(NAME)s_BACKEND_DSTATE" | |
| QEMU_EVENT = "_TRACE_%(NAME)s_EVENT" | |
| def api(self, fmt=None): | |
| if fmt is None: | |
| fmt = Event.QEMU_TRACE | |
| return fmt % {"name": self.name, "NAME": self.name.upper()} | |
| def read_events(fobj, fname): | |
| """Generate the output for the given (format, backends) pair. | |
| Parameters | |
| ---------- | |
| fobj : file | |
| Event description file. | |
| fname : str | |
| Name of event file | |
| Returns a list of Event objects | |
| """ | |
| events = [] | |
| for lineno, line in enumerate(fobj, 1): | |
| if line[-1] != '\n': | |
| raise ValueError("%s does not end with a new line" % fname) | |
| if not line.strip(): | |
| continue | |
| if line.lstrip().startswith('#'): | |
| continue | |
| try: | |
| event = Event.build(line, lineno, fname) | |
| except ValueError as e: | |
| arg0 = 'Error at %s:%d: %s' % (fname, lineno, e.args[0]) | |
| e.args = (arg0,) + e.args[1:] | |
| raise | |
| events.append(event) | |
| return events | |
| 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(events, group, format, backends, | |
| binary=None, probe_prefix=None): | |
| """Generate the output for the given (format, backends) pair. | |
| Parameters | |
| ---------- | |
| events : list | |
| list of Event objects to generate for | |
| group: str | |
| Name of the tracing group | |
| format : str | |
| Output format name. | |
| backends : list | |
| Output backend names. | |
| 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) == 0: | |
| raise TracetoolError("format not set") | |
| if not tracetool.format.exists(format): | |
| raise TracetoolError("unknown format: %s" % format) | |
| if len(backends) == 0: | |
| raise TracetoolError("no backends specified") | |
| for backend in backends: | |
| if not tracetool.backend.exists(backend): | |
| raise TracetoolError("unknown backend: %s" % backend) | |
| backend = tracetool.backend.Wrapper(backends, format) | |
| import tracetool.backend.dtrace | |
| tracetool.backend.dtrace.BINARY = binary | |
| tracetool.backend.dtrace.PROBEPREFIX = probe_prefix | |
| tracetool.format.generate(events, format, backend, group) | |
| def posix_relpath(path, start=None): | |
| try: | |
| path = os.path.relpath(path, start) | |
| except ValueError: | |
| pass | |
| return PurePath(path).as_posix() |