gprof2dot.py

#!/usr/bin/env python
#
# Copyright 2008-2009 Jose Fonseca
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

"""Generate a dot graph from the output of several profilers."""

__author__ = "Jose Fonseca"

__version__ = "1.0"


import sys
import math
import os.path
import re
import textwrap
import optparse
import xml.parsers.expat


try:
    # Debugging helper module
    import debug
except ImportError:
    pass


def percentage(p):
    return "%.02f%%" % (p*100.0,)

def add(a, b):
    return a + b

def equal(a, b):
    if a == b:
        return a
    else:
        return None

def fail(a, b):
    assert False


tol = 2 ** -23

def ratio(numerator, denominator):
    try:
        ratio = float(numerator)/float(denominator)
    except ZeroDivisionError:
        # 0/0 is undefined, but 1.0 yields more useful results
        return 1.0
    if ratio < 0.0:
        if ratio < -tol:
            sys.stderr.write('warning: negative ratio (%s/%s)\n' % (numerator, denominator))
        return 0.0
    if ratio > 1.0:
        if ratio > 1.0 + tol:
            sys.stderr.write('warning: ratio greater than one (%s/%s)\n' % (numerator, denominator))
        return 1.0
    return ratio


class UndefinedEvent(Exception):
    """Raised when attempting to get an event which is undefined."""

    def __init__(self, event):
        Exception.__init__(self)
        self.event = event

    def __str__(self):
        return 'unspecified event %s' % self.event.name


class Event(object):
    """Describe a kind of event, and its basic operations."""

    def __init__(self, name, null, aggregator, formatter = str):
        self.name = name
        self._null = null
        self._aggregator = aggregator
        self._formatter = formatter

    def __eq__(self, other):
        return self is other

    def __hash__(self):
        return id(self)

    def null(self):
        return self._null

    def aggregate(self, val1, val2):
        """Aggregate two event values."""
        assert val1 is not None
        assert val2 is not None
        return self._aggregator(val1, val2)

    def format(self, val):
        """Format an event value."""
        assert val is not None
        return self._formatter(val)


MODULE = Event("Module", None, equal)
PROCESS = Event("Process", None, equal)

CALLS = Event("Calls", 0, add)
SAMPLES = Event("Samples", 0, add)
SAMPLES2 = Event("Samples", 0, add)

TIME = Event("Time", 0.0, add, lambda x: '(' + str(x) + ')')
TIME_RATIO = Event("Time ratio", 0.0, add, lambda x: '(' + percentage(x) + ')')
TOTAL_TIME = Event("Total time", 0.0, fail)
TOTAL_TIME_RATIO = Event("Total time ratio", 0.0, fail, percentage)

CALL_RATIO = Event("Call ratio", 0.0, add, percentage)

PRUNE_RATIO = Event("Prune ratio", 0.0, add, percentage)


class Object(object):
    """Base class for all objects in profile which can store events."""

    def __init__(self, events=None):
        if events is None:
            self.events = {}
        else:
            self.events = events

    def __hash__(self):
        return id(self)

    def __eq__(self, other):
        return self is other

    def __contains__(self, event):
        return event in self.events

    def __getitem__(self, event):
        try:
            return self.events[event]
        except KeyError:
            raise UndefinedEvent(event)

    def __setitem__(self, event, value):
        if value is None:
            if event in self.events:
                del self.events[event]
        else:
            self.events[event] = value


class Call(Object):
    """A call between functions.

    There should be at most one call object for every pair of functions.
    """

    def __init__(self, callee_id):
        Object.__init__(self)
        self.callee_id = callee_id


class Function(Object):
    """A function."""

    def __init__(self, id, name):
        Object.__init__(self)
        self.id = id
        self.name = name
        self.calls = {}
        self.cycle = None

    def add_call(self, call):
        if call.callee_id in self.calls:
            sys.stderr.write('warning: overwriting call from function %s to %s\n' % (str(self.id), str(call.callee_id)))
        self.calls[call.callee_id] = call

    # TODO: write utility functions

    def __repr__(self):
        return self.name


class Cycle(Object):
    """A cycle made from recursive function calls."""

    def __init__(self):
        Object.__init__(self)
        # XXX: Do cycles need an id?
        self.functions = set()

    def add_function(self, function):
        assert function not in self.functions
        self.functions.add(function)
        # XXX: Aggregate events?
        if function.cycle is not None:
            for other in function.cycle.functions:
                if function not in self.functions:
                    self.add_function(other)
        function.cycle = self


class Profile(Object):
    """The whole profile."""

    def __init__(self):
        Object.__init__(self)
        self.functions = {}
        self.cycles = []

    def add_function(self, function):
        if function.id in self.functions:
            sys.stderr.write('warning: overwriting function %s (id %s)\n' % (function.name, str(function.id)))
        self.functions[function.id] = function

    def add_cycle(self, cycle):
        self.cycles.append(cycle)

    def validate(self):
        """Validate the edges."""

        for function in self.functions.itervalues():
            for callee_id in function.calls.keys():
                assert function.calls[callee_id].callee_id == callee_id
                if callee_id not in self.functions:
                    sys.stderr.write('warning: call to undefined function %s from function %s\n' % (str(callee_id), function.name))
                    del function.calls[callee_id]

    def find_cycles(self):
        """Find cycles using Tarjan's strongly connected components algorithm."""

        # Apply the Tarjan's algorithm successively until all functions are visited
        visited = set()
        for function in self.functions.itervalues():
            if function not in visited:
                self._tarjan(function, 0, [], {}, {}, visited)
        cycles = []
        for function in self.functions.itervalues():
            if function.cycle is not None and function.cycle not in cycles:
                cycles.append(function.cycle)
        self.cycles = cycles
        if 0:
            for cycle in cycles:
                sys.stderr.write("Cycle:\n")
                for member in cycle.functions:
                    sys.stderr.write("\t%s\n" % member.name)

    def _tarjan(self, function, order, stack, orders, lowlinks, visited):
        """Tarjan's strongly connected components algorithm.

        See also:
        - http://en.wikipedia.org/wiki/Tarjan's_strongly_connected_components_algorithm
        """

        visited.add(function)
        orders[function] = order
        lowlinks[function] = order
        order += 1
        pos = len(stack)
        stack.append(function)
        for call in function.calls.itervalues():
            callee = self.functions[call.callee_id]
            # TODO: use a set to optimize lookup
            if callee not in orders:
                order = self._tarjan(callee, order, stack, orders, lowlinks, visited)
                lowlinks[function] = min(lowlinks[function], lowlinks[callee])
            elif callee in stack:
                lowlinks[function] = min(lowlinks[function], orders[callee])
        if lowlinks[function] == orders[function]:
            # Strongly connected component found
            members = stack[pos:]
            del stack[pos:]
            if len(members) > 1:
                cycle = Cycle()
                for member in members:
                    cycle.add_function(member)
        return order

    def call_ratios(self, event):
        # Aggregate for incoming calls
        cycle_totals = {}
        for cycle in self.cycles:
            cycle_totals[cycle] = 0.0
        function_totals = {}
        for function in self.functions.itervalues():
            function_totals[function] = 0.0
        for function in self.functions.itervalues():
            for call in function.calls.itervalues():
                if call.callee_id != function.id:
                    callee = self.functions[call.callee_id]
                    function_totals[callee] += call[event]
                    if callee.cycle is not None and callee.cycle is not function.cycle:
                        cycle_totals[callee.cycle] += call[event]

        # Compute the ratios
        for function in self.functions.itervalues():
            for call in function.calls.itervalues():
                assert CALL_RATIO not in call
                if call.callee_id != function.id:
                    callee = self.functions[call.callee_id]
                    if callee.cycle is not None and callee.cycle is not function.cycle:
                        total = cycle_totals[callee.cycle]
                    else:
                        total = function_totals[callee]
                    call[CALL_RATIO] = ratio(call[event], total)

    def integrate(self, outevent, inevent):
        """Propagate function time ratio allong the function calls.

        Must be called after finding the cycles.

        See also:
        - http://citeseer.ist.psu.edu/graham82gprof.html
        """

        # Sanity checking
        assert outevent not in self
        for function in self.functions.itervalues():
            assert outevent not in function
            assert inevent in function
            for call in function.calls.itervalues():
                assert outevent not in call
                if call.callee_id != function.id:
                    assert CALL_RATIO in call

        # Aggregate the input for each cycle
        for cycle in self.cycles:
            total = inevent.null()
            for function in self.functions.itervalues():
                total = inevent.aggregate(total, function[inevent])
            self[inevent] = total

        # Integrate along the edges
        total = inevent.null()
        for function in self.functions.itervalues():
            total = inevent.aggregate(total, function[inevent])
            self._integrate_function(function, outevent, inevent)
        self[outevent] = total

    def _integrate_function(self, function, outevent, inevent):
        if function.cycle is not None:
            return self._integrate_cycle(function.cycle, outevent, inevent)
        else:
            if outevent not in function:
                total = function[inevent]
                for call in function.calls.itervalues():
                    if call.callee_id != function.id:
                        total += self._integrate_call(call, outevent, inevent)
                function[outevent] = total
            return function[outevent]

    def _integrate_call(self, call, outevent, inevent):
        assert outevent not in call
        assert CALL_RATIO in call
        callee = self.functions[call.callee_id]
        subtotal = call[CALL_RATIO]*self._integrate_function(callee, outevent, inevent)
        call[outevent] = subtotal
        return subtotal

    def _integrate_cycle(self, cycle, outevent, inevent):
        if outevent not in cycle:

            total = inevent.null()
            for member in cycle.functions:
                subtotal = member[inevent]
                for call in member.calls.itervalues():
                    callee = self.functions[call.callee_id]
                    if callee.cycle is not cycle:
                        subtotal += self._integrate_call(call, outevent, inevent)
                total += subtotal
            cycle[outevent] = total

            callees = {}
            for function in self.functions.itervalues():
                if function.cycle is not cycle:
                    for call in function.calls.itervalues():
                        callee = self.functions[call.callee_id]
                        if callee.cycle is cycle:
                            try:
                                callees[callee] += call[CALL_RATIO]
                            except KeyError:
                                callees[callee] = call[CALL_RATIO]

            for callee, call_ratio in callees.iteritems():
                ranks = {}
                call_ratios = {}
                partials = {}
                self._rank_cycle_function(cycle, callee, 0, ranks)
                self._call_ratios_cycle(cycle, callee, ranks, call_ratios, set())
                partial = self._integrate_cycle_function(cycle, callee, call_ratio, partials, ranks, call_ratios, outevent, inevent)
                assert partial == max(partials.values())
                assert not total or abs(1.0 - partial/(call_ratio*total)) <= 0.001

        return cycle[outevent]

    def _rank_cycle_function(self, cycle, function, rank, ranks):
        if function not in ranks or ranks[function] > rank:
            ranks[function] = rank
            for call in function.calls.itervalues():
                if call.callee_id != function.id:
                    callee = self.functions[call.callee_id]
                    if callee.cycle is cycle:
                        self._rank_cycle_function(cycle, callee, rank + 1, ranks)

    def _call_ratios_cycle(self, cycle, function, ranks, call_ratios, visited):
        if function not in visited:
            visited.add(function)
            for call in function.calls.itervalues():
                if call.callee_id != function.id:
                    callee = self.functions[call.callee_id]
                    if callee.cycle is cycle:
                        if ranks[callee] > ranks[function]:
                            call_ratios[callee] = call_ratios.get(callee, 0.0) + call[CALL_RATIO]
                            self._call_ratios_cycle(cycle, callee, ranks, call_ratios, visited)

    def _integrate_cycle_function(self, cycle, function, partial_ratio, partials, ranks, call_ratios, outevent, inevent):
        if function not in partials:
            partial = partial_ratio*function[inevent]
            for call in function.calls.itervalues():
                if call.callee_id != function.id:
                    callee = self.functions[call.callee_id]
                    if callee.cycle is not cycle:
                        assert outevent in call
                        partial += partial_ratio*call[outevent]
                    else:
                        if ranks[callee] > ranks[function]:
                            callee_partial = self._integrate_cycle_function(cycle, callee, partial_ratio, partials, ranks, call_ratios, outevent, inevent)
                            call_ratio = ratio(call[CALL_RATIO], call_ratios[callee])
                            call_partial = call_ratio*callee_partial
                            try:
                                call[outevent] += call_partial
                            except UndefinedEvent:
                                call[outevent] = call_partial
                            partial += call_partial
            partials[function] = partial
            try:
                function[outevent] += partial
            except UndefinedEvent:
                function[outevent] = partial
        return partials[function]

    def aggregate(self, event):
        """Aggregate an event for the whole profile."""

        total = event.null()
        for function in self.functions.itervalues():
            try:
                total = event.aggregate(total, function[event])
            except UndefinedEvent:
                return
        self[event] = total

    def ratio(self, outevent, inevent):
        assert outevent not in self
        assert inevent in self
        for function in self.functions.itervalues():
            assert outevent not in function
            assert inevent in function
            function[outevent] = ratio(function[inevent], self[inevent])
            for call in function.calls.itervalues():
                assert outevent not in call
                if inevent in call:
                    call[outevent] = ratio(call[inevent], self[inevent])
        self[outevent] = 1.0

    def prune(self, node_thres, edge_thres):
        """Prune the profile"""

        # compute the prune ratios
        for function in self.functions.itervalues():
            try:
                function[PRUNE_RATIO] = function[TOTAL_TIME_RATIO]
            except UndefinedEvent:
                pass

            for call in function.calls.itervalues():
                callee = self.functions[call.callee_id]

                if TOTAL_TIME_RATIO in call:
                    # handle exact cases first
                    call[PRUNE_RATIO] = call[TOTAL_TIME_RATIO]
                else:
                    try:
                        # make a safe estimate
                        call[PRUNE_RATIO] = min(function[TOTAL_TIME_RATIO], callee[TOTAL_TIME_RATIO])
                    except UndefinedEvent:
                        pass

        # prune the nodes
        for function_id in self.functions.keys():
            function = self.functions[function_id]
            try:
                if function[PRUNE_RATIO] < node_thres:
                    del self.functions[function_id]
            except UndefinedEvent:
                pass

        # prune the egdes
        for function in self.functions.itervalues():
            for callee_id in function.calls.keys():
                call = function.calls[callee_id]
                try:
                    if callee_id not in self.functions or call[PRUNE_RATIO] < edge_thres:
                        del function.calls[callee_id]
                except UndefinedEvent:
                    pass

    def dump(self):
        for function in self.functions.itervalues():
            sys.stderr.write('Function %s:\n' % (function.name,))
            self._dump_events(function.events)
            for call in function.calls.itervalues():
                callee = self.functions[call.callee_id]
                sys.stderr.write('  Call %s:\n' % (callee.name,))
                self._dump_events(call.events)

    def _dump_events(self, events):
        for event, value in events.iteritems():
            sys.stderr.write('    %s: %s\n' % (event.name, event.format(value)))


class Struct:
    """Masquerade a dictionary with a structure-like behavior."""

    def __init__(self, attrs = None):
        if attrs is None:
            attrs = {}
        self.__dict__['_attrs'] = attrs

    def __getattr__(self, name):
        try:
            return self._attrs[name]
        except KeyError:
            raise AttributeError(name)

    def __setattr__(self, name, value):
        self._attrs[name] = value

    def __str__(self):
        return str(self._attrs)

    def __repr__(self):
        return repr(self._attrs)


class ParseError(Exception):
    """Raised when parsing to signal mismatches."""

    def __init__(self, msg, line):
        self.msg = msg
        # TODO: store more source line information
        self.line = line

    def __str__(self):
        return '%s: %r' % (self.msg, self.line)


class Parser:
    """Parser interface."""

    def __init__(self):
        pass

    def parse(self):
        raise NotImplementedError


class LineParser(Parser):
    """Base class for parsers that read line-based formats."""

    def __init__(self, file):
        Parser.__init__(self)
        self._file = file
        self.__line = None
        self.__eof = False

    def readline(self):
        line = self._file.readline()
        if not line:
            self.__line = ''
            self.__eof = True
        self.__line = line.rstrip('\r\n')

    def lookahead(self):
        assert self.__line is not None
        return self.__line

    def consume(self):
        assert self.__line is not None
        line = self.__line
        self.readline()
        return line

    def eof(self):
        assert self.__line is not None
        return self.__eof


XML_ELEMENT_START, XML_ELEMENT_END, XML_CHARACTER_DATA, XML_EOF = range(4)


class XmlToken:

    def __init__(self, type, name_or_data, attrs = None, line = None, column = None):
        assert type in (XML_ELEMENT_START, XML_ELEMENT_END, XML_CHARACTER_DATA, XML_EOF)
        self.type = type
        self.name_or_data = name_or_data
        self.attrs = attrs
        self.line = line
        self.column = column

    def __str__(self):
        if self.type == XML_ELEMENT_START:
            return '<' + self.name_or_data + ' ...>'
        if self.type == XML_ELEMENT_END:
            return '</' + self.name_or_data + '>'
        if self.type == XML_CHARACTER_DATA:
            return self.name_or_data
        if self.type == XML_EOF:
            return 'end of file'
        assert 0


class XmlTokenizer:
    """Expat based XML tokenizer."""

    def __init__(self, fp, skip_ws = True):
        self.fp = fp
        self.tokens = []
        self.index = 0
        self.final = False
        self.skip_ws = skip_ws

        self.character_pos = 0, 0
        self.character_data = ''

        self.parser = xml.parsers.expat.ParserCreate()
        self.parser.StartElementHandler  = self.handle_element_start
        self.parser.EndElementHandler    = self.handle_element_end
        self.parser.CharacterDataHandler = self.handle_character_data

    def handle_element_start(self, name, attributes):
        self.finish_character_data()
        line, column = self.pos()
        token = XmlToken(XML_ELEMENT_START, name, attributes, line, column)
        self.tokens.append(token)

    def handle_element_end(self, name):
        self.finish_character_data()
        line, column = self.pos()
        token = XmlToken(XML_ELEMENT_END, name, None, line, column)
        self.tokens.append(token)

    def handle_character_data(self, data):
        if not self.character_data:
            self.character_pos = self.pos()
        self.character_data += data

    def finish_character_data(self):
        if self.character_data:
            if not self.skip_ws or not self.character_data.isspace():
                line, column = self.character_pos
                token = XmlToken(XML_CHARACTER_DATA, self.character_data, None, line, column)
                self.tokens.append(token)
            self.character_data = ''

    def next(self):
        size = 16*1024
        while self.index >= len(self.tokens) and not self.final:
            self.tokens = []
            self.index = 0
            data = self.fp.read(size)
            self.final = len(data) < size
            try:
                self.parser.Parse(data, self.final)
            except xml.parsers.expat.ExpatError, e:
                #if e.code == xml.parsers.expat.errors.XML_ERROR_NO_ELEMENTS:
                if e.code == 3:
                    pass
                else:
                    raise e
        if self.index >= len(self.tokens):
            line, column = self.pos()
            token = XmlToken(XML_EOF, None, None, line, column)
        else:
            token = self.tokens[self.index]
            self.index += 1
        return token

    def pos(self):
        return self.parser.CurrentLineNumber, self.parser.CurrentColumnNumber


class XmlTokenMismatch(Exception):

    def __init__(self, expected, found):
        self.expected = expected
        self.found = found

    def __str__(self):
        return '%u:%u: %s expected, %s found' % (self.found.line, self.found.column, str(self.expected), str(self.found))


class XmlParser(Parser):
    """Base XML document parser."""

    def __init__(self, fp):
        Parser.__init__(self)
        self.tokenizer = XmlTokenizer(fp)
        self.consume()

    def consume(self):
        self.token = self.tokenizer.next()

    def match_element_start(self, name):
        return self.token.type == XML_ELEMENT_START and self.token.name_or_data == name

    def match_element_end(self, name):
        return self.token.type == XML_ELEMENT_END and self.token.name_or_data == name

    def element_start(self, name):
        while self.token.type == XML_CHARACTER_DATA:
            self.consume()
        if self.token.type != XML_ELEMENT_START:
            raise XmlTokenMismatch(XmlToken(XML_ELEMENT_START, name), self.token)
        if self.token.name_or_data != name:
            raise XmlTokenMismatch(XmlToken(XML_ELEMENT_START, name), self.token)
        attrs = self.token.attrs
        self.consume()
        return attrs

    def element_end(self, name):
        while self.token.type == XML_CHARACTER_DATA:
            self.consume()
        if self.token.type != XML_ELEMENT_END:
            raise XmlTokenMismatch(XmlToken(XML_ELEMENT_END, name), self.token)
        if self.token.name_or_data != name:
            raise XmlTokenMismatch(XmlToken(XML_ELEMENT_END, name), self.token)
        self.consume()

    def character_data(self, strip = True):
        data = ''
        while self.token.type == XML_CHARACTER_DATA:
            data += self.token.name_or_data
            self.consume()
        if strip:
            data = data.strip()
        return data


class GprofParser(Parser):
    """Parser for GNU gprof output.

    See also:
    - Chapter "Interpreting gprof's Output" from the GNU gprof manual
      http://sourceware.org/binutils/docs-2.18/gprof/Call-Graph.html#Call-Graph
    - File "cg_print.c" from the GNU gprof source code
      http://sourceware.org/cgi-bin/cvsweb.cgi/~checkout~/src/gprof/cg_print.c?rev=1.12&cvsroot=src
    """

    def __init__(self, fp):
        Parser.__init__(self)
        self.fp = fp
        self.functions = {}
        self.cycles = {}

    def readline(self):
        line = self.fp.readline()
        if not line:
            sys.stderr.write('error: unexpected end of file\n')
            sys.exit(1)
        line = line.rstrip('\r\n')
        return line

    _int_re = re.compile(r'^\d+$')
    _float_re = re.compile(r'^\d+\.\d+$')

    def translate(self, mo):
        """Extract a structure from a match object, while translating the types in the process."""
        attrs = {}
        groupdict = mo.groupdict()
        for name, value in groupdict.iteritems():
            if value is None:
                value = None
            elif self._int_re.match(value):
                value = int(value)
            elif self._float_re.match(value):
                value = float(value)
            attrs[name] = (value)
        return Struct(attrs)

    _cg_header_re = re.compile(
        # original gprof header
        r'^\s+called/total\s+parents\s*$|' +
        r'^index\s+%time\s+self\s+descendents\s+called\+self\s+name\s+index\s*$|' +
        r'^\s+called/total\s+children\s*$|' +
        # GNU gprof header
        r'^index\s+%\s+time\s+self\s+children\s+called\s+name\s*$'
    )

    _cg_ignore_re = re.compile(
        # spontaneous
        r'^\s+<spontaneous>\s*$|'
        # internal calls (such as "mcount")
        r'^.*\((\d+)\)$'
    )

    _cg_primary_re = re.compile(
        r'^\[(?P<index>\d+)\]?' +
        r'\s+(?P<percentage_time>\d+\.\d+)' +
        r'\s+(?P<self>\d+\.\d+)' +
        r'\s+(?P<descendants>\d+\.\d+)' +
        r'\s+(?:(?P<called>\d+)(?:\+(?P<called_self>\d+))?)?' +
        r'\s+(?P<name>\S.*?)' +
        r'(?:\s+<cycle\s(?P<cycle>\d+)>)?' +
        r'\s\[(\d+)\]$'
    )

    _cg_parent_re = re.compile(
        r'^\s+(?P<self>\d+\.\d+)?' +
        r'\s+(?P<descendants>\d+\.\d+)?' +
        r'\s+(?P<called>\d+)(?:/(?P<called_total>\d+))?' +
        r'\s+(?P<name>\S.*?)' +
        r'(?:\s+<cycle\s(?P<cycle>\d+)>)?' +
        r'\s\[(?P<index>\d+)\]$'
    )

    _cg_child_re = _cg_parent_re

    _cg_cycle_header_re = re.compile(
        r'^\[(?P<index>\d+)\]?' +
        r'\s+(?P<percentage_time>\d+\.\d+)' +
        r'\s+(?P<self>\d+\.\d+)' +
        r'\s+(?P<descendants>\d+\.\d+)' +
        r'\s+(?:(?P<called>\d+)(?:\+(?P<called_self>\d+))?)?' +
        r'\s+<cycle\s(?P<cycle>\d+)\sas\sa\swhole>' +
        r'\s\[(\d+)\]$'
    )

    _cg_cycle_member_re = re.compile(
        r'^\s+(?P<self>\d+\.\d+)?' +
        r'\s+(?P<descendants>\d+\.\d+)?' +
        r'\s+(?P<called>\d+)(?:\+(?P<called_self>\d+))?' +
        r'\s+(?P<name>\S.*?)' +
        r'(?:\s+<cycle\s(?P<cycle>\d+)>)?' +
        r'\s\[(?P<index>\d+)\]$'
    )

    _cg_sep_re = re.compile(r'^--+$')

    def parse_function_entry(self, lines):
        parents = []
        children = []

        while True:
            if not lines:
                sys.stderr.write('warning: unexpected end of entry\n')
            line = lines.pop(0)
            if line.startswith('['):
                break

            # read function parent line
            mo = self._cg_parent_re.match(line)
            if not mo:
                if self._cg_ignore_re.match(line):
                    continue
                sys.stderr.write('warning: unrecognized call graph entry: %r\n' % line)
            else:
                parent = self.translate(mo)
                parents.append(parent)

        # read primary line
        mo = self._cg_primary_re.match(line)
        if not mo:
            sys.stderr.write('warning: unrecognized call graph entry: %r\n' % line)
            return
        else:
            function = self.translate(mo)

        while lines:
            line = lines.pop(0)

            # read function subroutine line
            mo = self._cg_child_re.match(line)
            if not mo:
                if self._cg_ignore_re.match(line):
                    continue
                sys.stderr.write('warning: unrecognized call graph entry: %r\n' % line)
            else:
                child = self.translate(mo)
                children.append(child)

        function.parents = parents
        function.children = children

        self.functions[function.index] = function

    def parse_cycle_entry(self, lines):

        # read cycle header line
        line = lines[0]
        mo = self._cg_cycle_header_re.match(line)
        if not mo:
            sys.stderr.write('warning: unrecognized call graph entry: %r\n' % line)
            return
        cycle = self.translate(mo)

        # read cycle member lines
        cycle.functions = []
        for line in lines[1:]:
            mo = self._cg_cycle_member_re.match(line)
            if not mo:
                sys.stderr.write('warning: unrecognized call graph entry: %r\n' % line)
                continue
            call = self.translate(mo)
            cycle.functions.append(call)

        self.cycles[cycle.cycle] = cycle

    def parse_cg_entry(self, lines):
        if lines[0].startswith("["):
            self.parse_cycle_entry(lines)
        else:
            self.parse_function_entry(lines)

    def parse_cg(self):
        """Parse the call graph."""

        # skip call graph header
        while not self._cg_header_re.match(self.readline()):
            pass
        line = self.readline()
        while self._cg_header_re.match(line):
            line = self.readline()

        # process call graph entries
        entry_lines = []
        while line != '\014': # form feed
            if line and not line.isspace():
                if self._cg_sep_re.match(line):
                    self.parse_cg_entry(entry_lines)
                    entry_lines = []
                else:
                    entry_lines.append(line)
            line = self.readline()

    def parse(self):
        self.parse_cg()
        self.fp.close()

        profile = Profile()
        profile[TIME] = 0.0

        cycles = {}
        for index in self.cycles.iterkeys():
            cycles[index] = Cycle()

        for entry in self.functions.itervalues():
            # populate the function
            function = Function(entry.index, entry.name)
            function[TIME] = entry.self
            if entry.called is not None:
                function[CALLS] = entry.called
            if entry.called_self is not None:
                call = Call(entry.index)
                call[CALLS] = entry.called_self
                function[CALLS] += entry.called_self

            # populate the function calls
            for child in entry.children:
                call = Call(child.index)

                assert child.called is not None
                call[CALLS] = child.called

                if child.index not in self.functions:
                    # NOTE: functions that were never called but were discovered by gprof's
                    # static call graph analysis dont have a call graph entry so we need
                    # to add them here
                    missing = Function(child.index, child.name)
                    function[TIME] = 0.0
                    function[CALLS] = 0
                    profile.add_function(missing)

                function.add_call(call)

            profile.add_function(function)

            if entry.cycle is not None:
                cycles[entry.cycle].add_function(function)

            profile[TIME] = profile[TIME] + function[TIME]

        for cycle in cycles.itervalues():
            profile.add_cycle(cycle)

        # Compute derived events
        profile.validate()
        profile.ratio(TIME_RATIO, TIME)
        profile.call_ratios(CALLS)
        profile.integrate(TOTAL_TIME, TIME)
        profile.ratio(TOTAL_TIME_RATIO, TOTAL_TIME)

        return profile


class OprofileParser(LineParser):
    """Parser for oprofile callgraph output.

    See also:
    - http://oprofile.sourceforge.net/doc/opreport.html#opreport-callgraph
    """

    _fields_re = {
        'samples': r'(?P<samples>\d+)',
        '%': r'(?P<percentage>\S+)',
        'linenr info': r'(?P<source>\(no location information\)|\S+:\d+)',
        'image name': r'(?P<image>\S+(?:\s\(tgid:[^)]*\))?)',
        'app name': r'(?P<application>\S+)',
        'symbol name': r'(?P<symbol>\(no symbols\)|.+?)',
    }

    def __init__(self, infile):
        LineParser.__init__(self, infile)
        self.entries = {}
        self.entry_re = None

    def add_entry(self, callers, function, callees):
        try:
            entry = self.entries[function.id]
        except KeyError:
            self.entries[function.id] = (callers, function, callees)
        else:
            callers_total, function_total, callees_total = entry
            self.update_subentries_dict(callers_total, callers)
            function_total.samples += function.samples
            self.update_subentries_dict(callees_total, callees)

    def update_subentries_dict(self, totals, partials):
        for partial in partials.itervalues():
            try:
                total = totals[partial.id]
            except KeyError:
                totals[partial.id] = partial
            else:
                total.samples += partial.samples

    def parse(self):
        # read lookahead
        self.readline()

        self.parse_header()
        while self.lookahead():
            self.parse_entry()

        profile = Profile()

        reverse_call_samples = {}

        # populate the profile
        profile[SAMPLES] = 0
        for _callers, _function, _callees in self.entries.itervalues():
            function = Function(_function.id, _function.name)
            function[SAMPLES] = _function.samples
            profile.add_function(function)
            profile[SAMPLES] += _function.samples

            if _function.application:
                function[PROCESS] = os.path.basename(_function.application)
            if _function.image:
                function[MODULE] = os.path.basename(_function.image)

            total_callee_samples = 0
            for _callee in _callees.itervalues():
                total_callee_samples += _callee.samples

            for _callee in _callees.itervalues():
                if not _callee.self:
                    call = Call(_callee.id)
                    call[SAMPLES2] = _callee.samples
                    function.add_call(call)

        # compute derived data
        profile.validate()
        profile.find_cycles()
        profile.ratio(TIME_RATIO, SAMPLES)
        profile.call_ratios(SAMPLES2)
        profile.integrate(TOTAL_TIME_RATIO, TIME_RATIO)

        return profile

    def parse_header(self):
        while not self.match_header():
            self.consume()
        line = self.lookahead()
        fields = re.split(r'\s\s+', line)
        entry_re = r'^\s*' + r'\s+'.join([self._fields_re[field] for field in fields]) + r'(?P<self>\s+\[self\])?$'
        self.entry_re = re.compile(entry_re)
        self.skip_separator()

    def parse_entry(self):
        callers = self.parse_subentries()
        if self.match_primary():
            function = self.parse_subentry()
            if function is not None:
                callees = self.parse_subentries()
                self.add_entry(callers, function, callees)
        self.skip_separator()

    def parse_subentries(self):
        subentries = {}
        while self.match_secondary():
            subentry = self.parse_subentry()
            subentries[subentry.id] = subentry
        return subentries

    def parse_subentry(self):
        entry = Struct()
        line = self.consume()
        mo = self.entry_re.match(line)
        if not mo:
            raise ParseError('failed to parse', line)
        fields = mo.groupdict()
        entry.samples = int(fields.get('samples', 0))
        entry.percentage = float(fields.get('percentage', 0.0))
        if 'source' in fields and fields['source'] != '(no location information)':
            source = fields['source']
            filename, lineno = source.split(':')
            entry.filename = filename
            entry.lineno = int(lineno)
        else:
            source = ''
            entry.filename = None
            entry.lineno = None
        entry.image = fields.get('image', '')
        entry.application = fields.get('application', '')
        if 'symbol' in fields and fields['symbol'] != '(no symbols)':
            entry.symbol = fields['symbol']
        else:
            entry.symbol = ''
        if entry.symbol.startswith('"') and entry.symbol.endswith('"'):
            entry.symbol = entry.symbol[1:-1]
        entry.id = ':'.join((entry.application, entry.image, source, entry.symbol))
        entry.self = fields.get('self', None) != None
        if entry.self:
            entry.id += ':self'
        if entry.symbol:
            entry.name = entry.symbol
        else:
            entry.name = entry.image
        return entry

    def skip_separator(self):
        while not self.match_separator():
            self.consume()
        self.consume()

    def match_header(self):
        line = self.lookahead()
        return line.startswith('samples')

    def match_separator(self):
        line = self.lookahead()
        return line == '-'*len(line)

    def match_primary(self):
        line = self.lookahead()
        return not line[:1].isspace()

    def match_secondary(self):
        line = self.lookahead()
        return line[:1].isspace()


class SharkParser(LineParser):
    """Parser for MacOSX Shark output.

    Author: tom@dbservice.com
    """

    def __init__(self, infile):
        LineParser.__init__(self, infile)
        self.stack = []
        self.entries = {}

    def add_entry(self, function):
        try:
            entry = self.entries[function.id]
        except KeyError:
            self.entries[function.id] = (function, { })
        else:
            function_total, callees_total = entry
            function_total.samples += function.samples

    def add_callee(self, function, callee):
        func, callees = self.entries[function.id]
        try:
            entry = callees[callee.id]
        except KeyError:
            callees[callee.id] = callee
        else:
            entry.samples += callee.samples

    def parse(self):
        self.readline()
        self.readline()
        self.readline()
        self.readline()

        match = re.compile(r'(?P<prefix>[|+ ]*)(?P<samples>\d+), (?P<symbol>[^,]+), (?P<image>.*)')

        while self.lookahead():
            line = self.consume()
            mo = match.match(line)
            if not mo:
                raise ParseError('failed to parse', line)

            fields = mo.groupdict()
            prefix = len(fields.get('prefix', 0)) / 2 - 1

            symbol = str(fields.get('symbol', 0))
            image = str(fields.get('image', 0))

            entry = Struct()
            entry.id = ':'.join([symbol, image])
            entry.samples = int(fields.get('samples', 0))

            entry.name = symbol
            entry.image = image

            # adjust the callstack
            if prefix < len(self.stack):
                del self.stack[prefix:]

            if prefix == len(self.stack):
                self.stack.append(entry)

            # if the callstack has had an entry, it's this functions caller
            if prefix > 0:
                self.add_callee(self.stack[prefix - 1], entry)

            self.add_entry(entry)

        profile = Profile()
        profile[SAMPLES] = 0
        for _function, _callees in self.entries.itervalues():
            function = Function(_function.id, _function.name)
            function[SAMPLES] = _function.samples
            profile.add_function(function)
            profile[SAMPLES] += _function.samples

            if _function.image:
                function[MODULE] = os.path.basename(_function.image)

            for _callee in _callees.itervalues():
                call = Call(_callee.id)
                call[SAMPLES] = _callee.samples
                function.add_call(call)

        # compute derived data
        profile.validate()
        profile.find_cycles()
        profile.ratio(TIME_RATIO, SAMPLES)
        profile.call_ratios(SAMPLES)
        profile.integrate(TOTAL_TIME_RATIO, TIME_RATIO)

        return profile


class AQtimeTable:

    def __init__(self, name, fields):
        self.name = name

        self.fields = fields
        self.field_column = {}
        for column in range(len(fields)):
            self.field_column[fields[column]] = column
        self.rows = []

    def __len__(self):
        return len(self.rows)

    def __iter__(self):
        for values, children in self.rows:
            fields = {}
            for name, value in zip(self.fields, values):
                fields[name] = value
            children = dict([(child.name, child) for child in children])
            yield fields, children
        raise StopIteration

    def add_row(self, values, children=()):
        self.rows.append((values, children))


class AQtimeParser(XmlParser):

    def __init__(self, stream):
        XmlParser.__init__(self, stream)
        self.tables = {}

    def parse(self):
        self.element_start('AQtime_Results')
        self.parse_headers()
        results = self.parse_results()
        self.element_end('AQtime_Results')
        return self.build_profile(results)

    def parse_headers(self):
        self.element_start('HEADERS')
        while self.token.type == XML_ELEMENT_START:
            self.parse_table_header()
        self.element_end('HEADERS')

    def parse_table_header(self):
        attrs = self.element_start('TABLE_HEADER')
        name = attrs['NAME']
        id = int(attrs['ID'])
        field_types = []
        field_names = []
        while self.token.type == XML_ELEMENT_START:
            field_type, field_name = self.parse_table_field()
            field_types.append(field_type)
            field_names.append(field_name)
        self.element_end('TABLE_HEADER')
        self.tables[id] = name, field_types, field_names

    def parse_table_field(self):
        attrs = self.element_start('TABLE_FIELD')
        type = attrs['TYPE']
        name = self.character_data()
        self.element_end('TABLE_FIELD')
        return type, name

    def parse_results(self):
        self.element_start('RESULTS')
        table = self.parse_data()
        self.element_end('RESULTS')
        return table

    def parse_data(self):
        rows = []
        attrs = self.element_start('DATA')
        table_id = int(attrs['TABLE_ID'])
        table_name, field_types, field_names = self.tables[table_id]
        table = AQtimeTable(table_name, field_names)
        while self.token.type == XML_ELEMENT_START:
            row, children = self.parse_row(field_types)
            table.add_row(row, children)
        self.element_end('DATA')
        return table

    def parse_row(self, field_types):
        row = [None]*len(field_types)
        children = []
        self.element_start('ROW')
        while self.token.type == XML_ELEMENT_START:
            if self.token.name_or_data == 'FIELD':
                field_id, field_value = self.parse_field(field_types)
                row[field_id] = field_value
            elif self.token.name_or_data == 'CHILDREN':
                children = self.parse_children()
            else:
                raise XmlTokenMismatch("<FIELD ...> or <CHILDREN ...>", self.token)
        self.element_end('ROW')
        return row, children

    def parse_field(self, field_types):
        attrs = self.element_start('FIELD')
        id = int(attrs['ID'])
        type = field_types[id]
        value = self.character_data()
        if type == 'Integer':
            value = int(value)
        elif type == 'Float':
            value = float(value)
        elif type == 'Address':
            value = int(value)
        elif type == 'String':
            pass
        else:
            assert False
        self.element_end('FIELD')
        return id, value

    def parse_children(self):
        children = []
        self.element_start('CHILDREN')
        while self.token.type == XML_ELEMENT_START:
            table = self.parse_data()
            assert table.name not in children
            children.append(table)
        self.element_end('CHILDREN')
        return children

    def build_profile(self, results):
        assert results.name == 'Routines'
        profile = Profile()
        profile[TIME] = 0.0
        for fields, tables in results:
            function = self.build_function(fields)
            children = tables['Children']
            for fields, _ in children:
                call = self.build_call(fields)
                function.add_call(call)
            profile.add_function(function)
            profile[TIME] = profile[TIME] + function[TIME]
        profile[TOTAL_TIME] = profile[TIME]
        profile.ratio(TOTAL_TIME_RATIO, TOTAL_TIME)
        return profile

    def build_function(self, fields):
        function = Function(self.build_id(fields), self.build_name(fields))
        function[TIME] = fields['Time']
        function[TOTAL_TIME] = fields['Time with Children']
        #function[TIME_RATIO] = fields['% Time']/100.0
        #function[TOTAL_TIME_RATIO] = fields['% with Children']/100.0
        return function

    def build_call(self, fields):
        call = Call(self.build_id(fields))
        call[TIME] = fields['Time']
        call[TOTAL_TIME] = fields['Time with Children']
        #call[TIME_RATIO] = fields['% Time']/100.0
        #call[TOTAL_TIME_RATIO] = fields['% with Children']/100.0
        return call

    def build_id(self, fields):
        return ':'.join([fields['Module Name'], fields['Unit Name'], fields['Routine Name']])

    def build_name(self, fields):
        # TODO: use more fields
        return fields['Routine Name']


class PstatsParser:
    """Parser python profiling statistics saved with te pstats module."""

    def __init__(self, *filename):
        import pstats
        try:
            self.stats = pstats.Stats(*filename)
        except ValueError:
            import hotshot.stats
            self.stats = hotshot.stats.load(filename[0])
        self.profile = Profile()
        self.function_ids = {}

    def get_function_name(self, (filename, line, name)):
        module = os.path.splitext(filename)[0]
        module = os.path.basename(module)
        return "%s:%d:%s" % (module, line, name)

    def get_function(self, key):
        try:
            id = self.function_ids[key]
        except KeyError:
            id = len(self.function_ids)
            name = self.get_function_name(key)
            function = Function(id, name)
            self.profile.functions[id] = function
            self.function_ids[key] = id
        else:
            function = self.profile.functions[id]
        return function

    def parse(self):
        self.profile[TIME] = 0.0
        self.profile[TOTAL_TIME] = self.stats.total_tt
        for fn, (cc, nc, tt, ct, callers) in self.stats.stats.iteritems():
            callee = self.get_function(fn)
            callee[CALLS] = nc
            callee[TOTAL_TIME] = ct
            callee[TIME] = tt
            self.profile[TIME] += tt
            self.profile[TOTAL_TIME] = max(self.profile[TOTAL_TIME], ct)
            for fn, value in callers.iteritems():
                caller = self.get_function(fn)
                call = Call(callee.id)
                if isinstance(value, tuple):
                    for i in xrange(0, len(value), 4):
                        nc, cc, tt, ct = value[i:i+4]
                        if CALLS in call:
                            call[CALLS] += cc
                        else:
                            call[CALLS] = cc

                        if TOTAL_TIME in call:
                            call[TOTAL_TIME] += ct
                        else:
                            call[TOTAL_TIME] = ct

                else:
                    call[CALLS] = value
                    call[TOTAL_TIME] = ratio(value, nc)*ct

                caller.add_call(call)
        #self.stats.print_stats()
        #self.stats.print_callees()

        # Compute derived events
        self.profile.validate()
        self.profile.ratio(TIME_RATIO, TIME)
        self.profile.ratio(TOTAL_TIME_RATIO, TOTAL_TIME)

        return self.profile


class Theme:

    def __init__(self,
            bgcolor = (0.0, 0.0, 1.0),
            mincolor = (0.0, 0.0, 0.0),
            maxcolor = (0.0, 0.0, 1.0),
            fontname = "Arial",
            minfontsize = 10.0,
            maxfontsize = 10.0,
            minpenwidth = 0.5,
            maxpenwidth = 4.0,
            gamma = 2.2):
        self.bgcolor = bgcolor
        self.mincolor = mincolor
        self.maxcolor = maxcolor
        self.fontname = fontname
        self.minfontsize = minfontsize
        self.maxfontsize = maxfontsize
        self.minpenwidth = minpenwidth
        self.maxpenwidth = maxpenwidth
        self.gamma = gamma

    def graph_bgcolor(self):
        return self.hsl_to_rgb(*self.bgcolor)

    def graph_fontname(self):
        return self.fontname

    def graph_fontsize(self):
        return self.minfontsize

    def node_bgcolor(self, weight):
        return self.color(weight)

    def node_fgcolor(self, weight):
        return self.graph_bgcolor()

    def node_fontsize(self, weight):
        return self.fontsize(weight)

    def edge_color(self, weight):
        return self.color(weight)

    def edge_fontsize(self, weight):
        return self.fontsize(weight)

    def edge_penwidth(self, weight):
        return max(weight*self.maxpenwidth, self.minpenwidth)

    def edge_arrowsize(self, weight):
        return 0.5 * math.sqrt(self.edge_penwidth(weight))

    def fontsize(self, weight):
        return max(weight**2 * self.maxfontsize, self.minfontsize)

    def color(self, weight):
        weight = min(max(weight, 0.0), 1.0)

        hmin, smin, lmin = self.mincolor
        hmax, smax, lmax = self.maxcolor

        h = hmin + weight*(hmax - hmin)
        s = smin + weight*(smax - smin)
        l = lmin + weight*(lmax - lmin)

        return self.hsl_to_rgb(h, s, l)

    def hsl_to_rgb(self, h, s, l):
        """Convert a color from HSL color-model to RGB.

        See also:
        - http://www.w3.org/TR/css3-color/#hsl-color
        """

        h = h % 1.0
        s = min(max(s, 0.0), 1.0)
        l = min(max(l, 0.0), 1.0)

        if l <= 0.5:
            m2 = l*(s + 1.0)
        else:
            m2 = l + s - l*s
        m1 = l*2.0 - m2
        r = self._hue_to_rgb(m1, m2, h + 1.0/3.0)
        g = self._hue_to_rgb(m1, m2, h)
        b = self._hue_to_rgb(m1, m2, h - 1.0/3.0)

        # Apply gamma correction
        r **= self.gamma
        g **= self.gamma
        b **= self.gamma

        return (r, g, b)

    def _hue_to_rgb(self, m1, m2, h):
        if h < 0.0:
            h += 1.0
        elif h > 1.0:
            h -= 1.0
        if h*6 < 1.0:
            return m1 + (m2 - m1)*h*6.0
        elif h*2 < 1.0:
            return m2
        elif h*3 < 2.0:
            return m1 + (m2 - m1)*(2.0/3.0 - h)*6.0
        else:
            return m1


TEMPERATURE_COLORMAP = Theme(
    mincolor = (2.0/3.0, 0.80, 0.25), # dark blue
    maxcolor = (0.0, 1.0, 0.5), # satured red
    gamma = 1.0
)

PINK_COLORMAP = Theme(
    mincolor = (0.0, 1.0, 0.90), # pink
    maxcolor = (0.0, 1.0, 0.5), # satured red
)

GRAY_COLORMAP = Theme(
    mincolor = (0.0, 0.0, 0.85), # light gray
    maxcolor = (0.0, 0.0, 0.0), # black
)

BW_COLORMAP = Theme(
    minfontsize = 8.0,
    maxfontsize = 24.0,
    mincolor = (0.0, 0.0, 0.0), # black
    maxcolor = (0.0, 0.0, 0.0), # black
    minpenwidth = 0.1,
    maxpenwidth = 8.0,
)


class DotWriter:
    """Writer for the DOT language.

    See also:
    - "The DOT Language" specification
      http://www.graphviz.org/doc/info/lang.html
    """

    def __init__(self, fp):
        self.fp = fp

    def graph(self, profile, theme):
        self.begin_graph()

        fontname = theme.graph_fontname()

        self.attr('graph', fontname=fontname, ranksep=0.25, nodesep=0.125)
        self.attr('node', fontname=fontname, shape="box", style="filled,rounded", fontcolor="white", width=0, height=0)
        self.attr('edge', fontname=fontname)

        for function in profile.functions.itervalues():
            labels = []
            for event in PROCESS, MODULE:
                if event in function.events:
                    label = event.format(function[event])
                    labels.append(label)
            labels.append(function.name)
            for event in TOTAL_TIME_RATIO, TIME_RATIO, CALLS:
                if event in function.events:
                    label = event.format(function[event])
                    labels.append(label)

            try:
                weight = function[PRUNE_RATIO]
            except UndefinedEvent:
                weight = 0.0

            label = '\n'.join(labels)
            self.node(function.id,
                label = label,
                color = self.color(theme.node_bgcolor(weight)),
                fontcolor = self.color(theme.node_fgcolor(weight)),
                fontsize = "%.2f" % theme.node_fontsize(weight),
            )

            for call in function.calls.itervalues():
                callee = profile.functions[call.callee_id]

                labels = []
                for event in TOTAL_TIME_RATIO, CALLS:
                    if event in call.events:
                        label = event.format(call[event])
                        labels.append(label)

                try:
                    weight = call[PRUNE_RATIO]
                except UndefinedEvent:
                    try:
                        weight = callee[PRUNE_RATIO]
                    except UndefinedEvent:
                        weight = 0.0

                label = '\n'.join(labels)

                self.edge(function.id, call.callee_id,
                    label = label,
                    color = self.color(theme.edge_color(weight)),
                    fontcolor = self.color(theme.edge_color(weight)),
                    fontsize = "%.2f" % theme.edge_fontsize(weight),
                    penwidth = "%.2f" % theme.edge_penwidth(weight),
                    labeldistance = "%.2f" % theme.edge_penwidth(weight),
                    arrowsize = "%.2f" % theme.edge_arrowsize(weight),
                )

        self.end_graph()

    def begin_graph(self):
        self.write('digraph {\n')

    def end_graph(self):
        self.write('}\n')

    def attr(self, what, **attrs):
        self.write("\t")
        self.write(what)
        self.attr_list(attrs)
        self.write(";\n")

    def node(self, node, **attrs):
        self.write("\t")
        self.id(node)
        self.attr_list(attrs)
        self.write(";\n")

    def edge(self, src, dst, **attrs):
        self.write("\t")
        self.id(src)
        self.write(" -> ")
        self.id(dst)
        self.attr_list(attrs)
        self.write(";\n")

    def attr_list(self, attrs):
        if not attrs:
            return
        self.write(' [')
        first = True
        for name, value in attrs.iteritems():
            if first:
                first = False
            else:
                self.write(", ")
            self.id(name)
            self.write('=')
            self.id(value)
        self.write(']')

    def id(self, id):
        if isinstance(id, (int, float)):
            s = str(id)
        elif isinstance(id, basestring):
            if id.isalnum():
                s = id
            else:
                s = self.escape(id)
        else:
            raise TypeError
        self.write(s)

    def color(self, (r, g, b)):

        def float2int(f):
            if f <= 0.0:
                return 0
            if f >= 1.0:
                return 255
            return int(255.0*f + 0.5)

        return "#" + "".join(["%02x" % float2int(c) for c in (r, g, b)])

    def escape(self, s):
        s = s.encode('utf-8')
        s = s.replace('\\', r'\\')
        s = s.replace('\n', r'\n')
        s = s.replace('\t', r'\t')
        s = s.replace('"', r'\"')
        return '"' + s + '"'

    def write(self, s):
        self.fp.write(s)


class Main:
    """Main program."""

    themes = {
            "color": TEMPERATURE_COLORMAP,
            "pink": PINK_COLORMAP,
            "gray": GRAY_COLORMAP,
            "bw": BW_COLORMAP,
    }

    def main(self):
        """Main program."""

        parser = optparse.OptionParser(
            usage="\n\t%prog [options] [file] ...",
            version="%%prog %s" % __version__)
        parser.add_option(
            '-o', '--output', metavar='FILE',
            type="string", dest="output",
            help="output filename [stdout]")
        parser.add_option(
            '-n', '--node-thres', metavar='PERCENTAGE',
            type="float", dest="node_thres", default=0.5,
            help="eliminate nodes below this threshold [default: %default]")
        parser.add_option(
            '-e', '--edge-thres', metavar='PERCENTAGE',
            type="float", dest="edge_thres", default=0.1,
            help="eliminate edges below this threshold [default: %default]")
        parser.add_option(
            '-f', '--format',
            type="choice", choices=('prof', 'oprofile', 'pstats', 'shark', 'aqtime'),
            dest="format", default="prof",
            help="profile format: prof, oprofile, shark, aqtime, or pstats [default: %default]")
        parser.add_option(
            '-c', '--colormap',
            type="choice", choices=('color', 'pink', 'gray', 'bw'),
            dest="theme", default="color",
            help="color map: color, pink, gray, or bw [default: %default]")
        parser.add_option(
            '-s', '--strip',
            action="store_true",
            dest="strip", default=False,
            help="strip function parameters, template parameters, and const modifiers from demangled C++ function names")
        parser.add_option(
            '-w', '--wrap',
            action="store_true",
            dest="wrap", default=False,
            help="wrap function names")
        (self.options, self.args) = parser.parse_args(sys.argv[1:])

        if len(self.args) > 1 and self.options.format != 'pstats':
            parser.error('incorrect number of arguments')

        try:
            self.theme = self.themes[self.options.theme]
        except KeyError:
            parser.error('invalid colormap \'%s\'' % self.options.theme)

        if self.options.format == 'prof':
            if not self.args:
                fp = sys.stdin
            else:
                fp = open(self.args[0], 'rt')
            parser = GprofParser(fp)
        elif self.options.format == 'oprofile':
            if not self.args:
                fp = sys.stdin
            else:
                fp = open(self.args[0], 'rt')
            parser = OprofileParser(fp)
        elif self.options.format == 'pstats':
            if not self.args:
                parser.error('at least a file must be specified for pstats input')
            parser = PstatsParser(*self.args)
        elif self.options.format == 'shark':
            if not self.args:
                fp = sys.stdin
            else:
                fp = open(self.args[0], 'rt')
            parser = SharkParser(fp)
        elif self.options.format == 'aqtime':
            if not self.args:
                fp = sys.stdin
            else:
                fp = open(self.args[0], 'rt')
            parser = AQtimeParser(fp)
        else:
            parser.error('invalid format \'%s\'' % self.options.format)

        self.profile = parser.parse()

        if self.options.output is None:
            self.output = sys.stdout
        else:
            self.output = open(self.options.output, 'wt')

        self.write_graph()

    _parenthesis_re = re.compile(r'\([^()]*\)')
    _angles_re = re.compile(r'<[^<>]*>')
    _const_re = re.compile(r'\s+const$')

    def strip_function_name(self, name):
        """Remove extraneous information from C++ demangled function names."""

        # Strip function parameters from name by recursively removing paired parenthesis
        while True:
            name, n = self._parenthesis_re.subn('', name)
            if not n:
                break

        # Strip const qualifier
        name = self._const_re.sub('', name)

        # Strip template parameters from name by recursively removing paired angles
        while True:
            name, n = self._angles_re.subn('', name)
            if not n:
                break

        return name

    def wrap_function_name(self, name):
        """Split the function name on multiple lines."""

        if len(name) > 32:
            ratio = 2.0/3.0
            height = max(int(len(name)/(1.0 - ratio) + 0.5), 1)
            width = max(len(name)/height, 32)
            # TODO: break lines in symbols
            name = textwrap.fill(name, width, break_long_words=False)

        # Take away spaces
        name = name.replace(", ", ",")
        name = name.replace("> >", ">>")
        name = name.replace("> >", ">>") # catch consecutive

        return name

    def compress_function_name(self, name):
        """Compress function name according to the user preferences."""

        if self.options.strip:
            name = self.strip_function_name(name)

        if self.options.wrap:
            name = self.wrap_function_name(name)

        # TODO: merge functions with same resulting name

        return name

    def write_graph(self):
        dot = DotWriter(self.output)
        profile = self.profile
        profile.prune(self.options.node_thres/100.0, self.options.edge_thres/100.0)

        for function in profile.functions.itervalues():
            function.name = self.compress_function_name(function.name)

        dot.graph(profile, self.theme)


if __name__ == '__main__':
    Main().main()