gprof2dot.py

#!/usr/bin/env python3
#
# Copyright 2008-2023 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 et al"


import sys
import math
import os.path
import re
import textwrap
import optparse
import xml.parsers.expat
import collections
import locale
import json
import fnmatch
import codecs
import io
import hashlib

assert sys.version_info[0] >= 3


########################################################################
# Model


MULTIPLICATION_SIGN = chr(0xd7)
timeFormat = "%.7g"


def times(x):
    return "%u%s" % (x, MULTIPLICATION_SIGN)

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

def fmttime(t):
    return timeFormat % t

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

def fail(a, b):
    assert False

# To enhance readability, labels are rounded to the number of decimal
# places corresponding to the tolerance value.
def round_difference(difference, tolerance):
    n = -math.floor(math.log10(tolerance))
    return round(difference, n)


def rescale_difference(x, min_val, max_val):
    return (x - min_val) / (max_val - min_val)


def min_max_difference(profile1, profile2):
    f1_events = [f1[TOTAL_TIME_RATIO] for _, f1 in sorted_iteritems(profile1.functions)]
    f2_events = [f2[TOTAL_TIME_RATIO] for _, f2 in sorted_iteritems(profile2.functions)]
    differences = []
    for i in range(len(f1_events)):
        try:
            differences.append(abs(f1_events[i] - f2_events[i]) * 100)
        except IndexError:
            differences.append(0)

    return min(differences), max(differences)


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:
    """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 __repr__(self):
        return self.name

    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)


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

# Count of samples where a given function was either executing or on the stack.
# This is used to calculate the total time ratio according to the
# straightforward method described in Mike Dunlavey's answer to
# stackoverflow.com/questions/1777556/alternatives-to-gprof, item 4 (the myth
# "that recursion is a tricky confusing issue"), last edited 2012-08-30: it's
# just the ratio of TOTAL_SAMPLES over the number of samples in the profile.
#
# Used only when totalMethod == callstacks
TOTAL_SAMPLES = Event("Samples", 0, add, times)

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

labels = {
    'self-time': TIME,
    'self-time-percentage': TIME_RATIO,
    'total-time': TOTAL_TIME,
    'total-time-percentage': TOTAL_TIME_RATIO,
}
defaultLabelNames = ['total-time-percentage', 'self-time-percentage']

totalMethod = 'callratios'


class 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 __lt__(self, other):
        return id(self) < id(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
        self.ratio = None
        self.weight = None


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

    def __init__(self, id, name):
        Object.__init__(self)
        self.id = id
        self.name = name
        self.module = None
        self.process = None
        self.calls = {}
        self.called = None
        self.weight = None
        self.cycle = None
        self.filename = 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

    def get_call(self, callee_id):
        if not callee_id in self.calls:
            call = Call(callee_id)
            call[SAMPLES] = 0
            call[SAMPLES2] = 0
            call[CALLS] = 0
            self.calls[callee_id] = call
        return self.calls[callee_id]

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

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

        name = self.name

        # 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

    # TODO: write utility functions

    def __repr__(self):
        return self.name

    def dump(self, sep1=",\n\t", sep2=":=", sep3="\n"):
        """ Returns as a string all information available in this Function object
            separators sep1:between entries
                       sep2:between attribute name and value,
                       sep3: inserted at end
        """
        return sep1.join(sep2.join([k,str(v)]) for (k,v) in sorted(self.__dict__.items())) + sep3


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

    def __init__(self):
        Object.__init__(self)
        self.functions = set()

    def add_function(self, function):
        assert function not in self.functions
        self.functions.add(function)
        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.values():
            for callee_id in list(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
        stack = []
        data = {}
        order = 0
        for function in self.functions.values():
            order = self._tarjan(function, order, stack, data)
        cycles = []
        for function in self.functions.values():
            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("\tFunction %s\n" % member.name)

    def prune_root(self, roots, depth=-1):
        visited = set()
        frontier = set([(root_node, depth) for root_node in roots])
        while len(frontier) > 0:
            node, node_depth = frontier.pop()
            visited.add(node)
            if node_depth == 0:
                continue
            f = self.functions[node]
            newNodes = set(f.calls.keys()) - visited
            frontier = frontier.union({(new_node, node_depth - 1) for new_node in newNodes})
        subtreeFunctions = {}
        for n in visited:
            f = self.functions[n]
            newCalls = {}
            for c in f.calls.keys():
                if c in visited:
                    newCalls[c] = f.calls[c]
            f.calls = newCalls
            subtreeFunctions[n] = f
        self.functions = subtreeFunctions

    def prune_leaf(self, leafs, depth=-1):
        edgesUp = collections.defaultdict(set)
        for f in self.functions.keys():
            for n in self.functions[f].calls.keys():
                edgesUp[n].add(f)
        # build the tree up
        visited = set()
        frontier = set([(leaf_node, depth) for leaf_node in leafs])
        while len(frontier) > 0:
            node, node_depth = frontier.pop()
            visited.add(node)
            if node_depth == 0:
                continue
            newNodes = edgesUp[node] - visited
            frontier = frontier.union({(new_node, node_depth - 1) for new_node in newNodes})
        downTree = set(self.functions.keys())
        upTree = visited
        path = downTree.intersection(upTree)
        pathFunctions = {}
        for n in path:
            f = self.functions[n]
            newCalls = {}
            for c in f.calls.keys():
                if c in path:
                    newCalls[c] = f.calls[c]
            f.calls = newCalls
            pathFunctions[n] = f
        self.functions = pathFunctions

    def getFunctionIds(self, funcName):
        function_names = {v.name: k for (k, v) in self.functions.items()}
        return [function_names[name] for name in fnmatch.filter(function_names.keys(), funcName)]

    def getFunctionId(self, funcName):
        for f in self.functions:
            if self.functions[f].name == funcName:
                return f
        return False

    def printFunctionIds(self, selector=None, file=sys.stderr):
        """ Print to file function entries selected by fnmatch.fnmatch like in
            method getFunctionIds, with following extensions:
             - selector starts with "%": dump all information available
             - selector is '+' or '-': select all function entries
        """
        if selector is None or selector in ("+", "*"):
            v = ",\n".join(("%s:\t%s" % (kf,self.functions[kf].name)
                            for kf in self.functions.keys()))
        else:
            if selector[0]=="%":
                selector=selector[1:]
                function_info={k:v for (k,v)
                               in self.functions.items()
                               if fnmatch.fnmatch(v.name,selector)}
                v = ",\n".join( ("%s\t({k})\t(%s)::\n\t%s" % (v.name,type(v),v.dump())
                                 for (k,v) in function_info.items()
                                  ))

            else:
                function_names = (v.name for v in self.functions.values())
                v = ",\n".join( ( nm for nm in fnmatch.filter(function_names,selector )))

        file.write(v+"\n")
        file.flush()

    class _TarjanData:
        def __init__(self, order):
            self.order = order
            self.lowlink = order
            self.onstack = False

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

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

        try:
            func_data = data[function.id]
            return order
        except KeyError:
            func_data = self._TarjanData(order)
            data[function.id] = func_data
        order += 1
        pos = len(stack)
        stack.append(function)
        func_data.onstack = True
        for call in function.calls.values():
            try:
                callee_data = data[call.callee_id]
                if callee_data.onstack:
                    func_data.lowlink = min(func_data.lowlink, callee_data.order)
            except KeyError:
                callee = self.functions[call.callee_id]
                order = self._tarjan(callee, order, stack, data)
                callee_data = data[call.callee_id]
                func_data.lowlink = min(func_data.lowlink, callee_data.lowlink)
        if func_data.lowlink == func_data.order:
            # Strongly connected component found
            members = stack[pos:]
            del stack[pos:]
            if len(members) > 1:
                cycle = Cycle()
                for member in members:
                    cycle.add_function(member)
                    data[member.id].onstack = False
            else:
                for member in members:
                    data[member.id].onstack = False
        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.values():
            function_totals[function] = 0.0

        # Pass 1:  function_total gets the sum of call[event] for all
        #          incoming arrows.  Same for cycle_total for all arrows
        #          that are coming into the *cycle* but are not part of it.
        for function in self.functions.values():
            for call in function.calls.values():
                if call.callee_id != function.id:
                    callee = self.functions[call.callee_id]
                    if event in call.events:
                        function_totals[callee] += call[event]
                        if callee.cycle is not None and callee.cycle is not function.cycle:
                            cycle_totals[callee.cycle] += call[event]
                    else:
                        sys.stderr.write("call_ratios: No data for " + function.name + " call to " + callee.name + "\n")

        # Pass 2:  Compute the ratios.  Each call[event] is scaled by the
        #          function_total of the callee.  Calls into cycles use the
        #          cycle_total, but not calls within cycles.
        for function in self.functions.values():
            for call in function.calls.values():
                assert call.ratio is None
                if call.callee_id != function.id:
                    callee = self.functions[call.callee_id]
                    if event in call.events:
                        if callee.cycle is not None and callee.cycle is not function.cycle:
                            total = cycle_totals[callee.cycle]
                        else:
                            total = function_totals[callee]
                        call.ratio = ratio(call[event], total)
                    else:
                        # Warnings here would only repeat those issued above.
                        call.ratio = 0.0

    def integrate(self, outevent, inevent):
        """Propagate function time ratio along 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.values():
            assert outevent not in function
            assert inevent in function
            for call in function.calls.values():
                assert outevent not in call
                if call.callee_id != function.id:
                    assert call.ratio is not None

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

        # Integrate along the edges
        total = inevent.null()
        for function in self.functions.values():
            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.values():
                    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 is not None
        callee = self.functions[call.callee_id]
        subtotal = 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:

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

            # Compute the time propagated to callers of this cycle
            callees = {}
            for function in self.functions.values():
                if function.cycle is not cycle:
                    for call in function.calls.values():
                        callee = self.functions[call.callee_id]
                        if callee.cycle is cycle:
                            try:
                                callees[callee] += call.ratio
                            except KeyError:
                                callees[callee] = call.ratio

            for member in cycle.functions:
                member[outevent] = outevent.null()

            for callee, call_ratio in callees.items():
                ranks = {}
                call_ratios = {}
                partials = {}
                self._rank_cycle_function(cycle, callee, 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)

                # Ensure `partial == max(partials.values())`, but with round-off tolerance
                max_partial = max(partials.values())
                assert abs(partial - max_partial) <= 1e-7*max_partial

                assert abs(call_ratio*total - partial) <= 0.001*call_ratio*total

        return cycle[outevent]

    def _rank_cycle_function(self, cycle, function, ranks):
        """Dijkstra's shortest paths algorithm.

        See also:
        - http://en.wikipedia.org/wiki/Dijkstra's_algorithm
        """

        import heapq
        Q = []
        Qd = {}
        p = {}
        visited = set([function])

        ranks[function] = 0
        for call in function.calls.values():
            if call.callee_id != function.id:
                callee = self.functions[call.callee_id]
                if callee.cycle is cycle:
                    ranks[callee] = 1
                    item = [ranks[callee], function, callee]
                    heapq.heappush(Q, item)
                    Qd[callee] = item

        while Q:
            cost, parent, member = heapq.heappop(Q)
            if member not in visited:
                p[member]= parent
                visited.add(member)
                for call in member.calls.values():
                    if call.callee_id != member.id:
                        callee = self.functions[call.callee_id]
                        if callee.cycle is cycle:
                            member_rank = ranks[member]
                            rank = ranks.get(callee)
                            if rank is not None:
                                if rank > 1 + member_rank:
                                    rank = 1 + member_rank
                                    ranks[callee] = rank
                                    Qd_callee = Qd[callee]
                                    Qd_callee[0] = rank
                                    Qd_callee[1] = member
                                    heapq._siftdown(Q, 0, Q.index(Qd_callee))
                            else:
                                rank = 1 + member_rank
                                ranks[callee] = rank
                                item = [rank, member, callee]
                                heapq.heappush(Q, item)
                                Qd[callee] = item

    def _call_ratios_cycle(self, cycle, function, ranks, call_ratios, visited):
        if function not in visited:
            visited.add(function)
            for call in function.calls.values():
                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.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.values():
                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.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.values():
            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.values():
            assert outevent not in function
            assert inevent in function
            function[outevent] = ratio(function[inevent], self[inevent])
            for call in function.calls.values():
                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, paths, color_nodes_by_selftime):
        """Prune the profile"""

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

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

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

        # prune the nodes
        for function_id in list(self.functions.keys()):
            function = self.functions[function_id]
            if function.weight is not None:
                if function.weight < node_thres:
                    del self.functions[function_id]

        # prune file paths
        for function_id in list(self.functions.keys()):
            function = self.functions[function_id]
            if paths and function.filename and not any(function.filename.startswith(path) for path in paths):
                del self.functions[function_id]
            elif paths and function.module and not any((function.module.find(path)>-1) for path in paths):
                del self.functions[function_id]

        # prune the edges
        for function in self.functions.values():
            for callee_id in list(function.calls.keys()):
                call = function.calls[callee_id]
                if callee_id not in self.functions or call.weight is not None and call.weight < edge_thres:
                    del function.calls[callee_id]

        if color_nodes_by_selftime:
            weights = []
            for function in self.functions.values():
                try:
                    weights.append(function[TIME_RATIO])
                except UndefinedEvent:
                    pass
            max_ratio = max(weights or [1])

            # apply rescaled weights for coloriung
            for function in self.functions.values():
                try:
                    function.weight = function[TIME_RATIO] / max_ratio
                except (ZeroDivisionError, UndefinedEvent):
                    pass

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

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



########################################################################
# Parsers


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):
        Exception.__init__(self)
        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."""

    stdinInput = True
    multipleInput = False

    def __init__(self):
        pass

    def parse(self):
        raise NotImplementedError


class JsonParser(Parser):
    """Parser for a custom JSON representation of profile data.

    See schema.json for details.
    """


    def __init__(self, stream):
        Parser.__init__(self)
        self.stream = stream

    def parse(self):

        obj = json.load(self.stream)

        assert obj['version'] == 0

        profile = Profile()
        profile[SAMPLES] = 0

        fns = obj['functions']

        for functionIndex in range(len(fns)):
            fn = fns[functionIndex]
            function = Function(functionIndex, fn['name'])
            try:
                function.module = fn['module']
            except KeyError:
                pass
            try:
                function.process = fn['process']
            except KeyError:
                pass
            function[SAMPLES] = 0
            function.called = 0
            profile.add_function(function)

        for event in obj['events']:
            callchain = []

            for functionIndex in event['callchain']:
                function = profile.functions[functionIndex]
                callchain.append(function)

            # increment the call count of the first in the callchain
            function = profile.functions[event['callchain'][0]]
            function.called = function.called + 1

            cost = event['cost'][0]

            callee = callchain[0]
            callee[SAMPLES] += cost
            profile[SAMPLES] += cost

            for caller in callchain[1:]:
                try:
                    call = caller.calls[callee.id]
                except KeyError:
                    call = Call(callee.id)
                    call[SAMPLES2] = cost
                    caller.add_call(call)
                else:
                    call[SAMPLES2] += cost

                callee = caller

        if False:
            profile.dump()

        # 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


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

    def __init__(self, stream):
        Parser.__init__(self)
        self._stream = stream
        self.__line = None
        self.__eof = False
        self.line_no = 0

    def readline(self):
        line = self._stream.readline()
        if not line:
            self.__line = ''
            self.__eof = True
        else:
            self.line_no += 1
        line = line.rstrip('\r\n')
        self.__line = line

    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
            self.parser.Parse(data, self.final)
        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):
        Exception.__init__(self)
        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.items():
            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:
            cycles[index] = Cycle()

        for entry in self.functions.values():
            # populate the function
            function = Function(entry.index, entry.name)
            function[TIME] = entry.self
            if entry.called is not None:
                function.called = entry.called
            if entry.called_self is not None:
                call = Call(entry.index)
                call[CALLS] = entry.called_self
                function.called += 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.called = 0
                    profile.add_function(missing)

                function.add_call(call)

            profile.add_function(function)

            if entry.cycle is not None:
                try:
                    cycle = cycles[entry.cycle]
                except KeyError:
                    sys.stderr.write('warning: <cycle %u as a whole> entry missing\n' % entry.cycle)
                    cycle = Cycle()
                    cycles[entry.cycle] = cycle
                cycle.add_function(function)

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

        for cycle in cycles.values():
            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


# Clone&hack of GprofParser for VTune Amplifier XE 2013 gprof-cc output.
# Tested only with AXE 2013 for Windows.
#   - Use total times as reported by AXE.
#   - In the absence of call counts, call ratios are faked from the relative
#     proportions of total time.  This affects only the weighting of the calls.
#   - Different header, separator, and end marker.
#   - Extra whitespace after function names.
#   - You get a full entry for <spontaneous>, which does not have parents.
#   - Cycles do have parents.  These are saved but unused (as they are
#     for functions).
#   - Disambiguated "unrecognized call graph entry" error messages.
# Notes:
#   - Total time of functions as reported by AXE passes the val3 test.
#   - CPU Time:Children in the input is sometimes a negative number.  This
#     value goes to the variable descendants, which is unused.
#   - The format of gprof-cc reports is unaffected by the use of
#       -knob enable-call-counts=true (no call counts, ever), or
#       -show-as=samples (results are quoted in seconds regardless).
class AXEParser(Parser):
    "Parser for VTune Amplifier XE 2013 gprof-cc report output."

    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.items():
            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(
        '^Index |'
        '^-----+ '
    )

    _cg_footer_re = re.compile(r'^Index\s+Function\s*$')

    _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<name>\S.*?)' +
        r'(?:\s+<cycle\s(?P<cycle>\d+)>)?' +
        r'\s+\[(\d+)\]' +
        r'\s*$'
    )

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

    _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+<cycle\s(?P<cycle>\d+)\sas\sa\swhole>' +
        r'\s+\[(\d+)\]' +
        r'\s*$'
    )

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

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

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

            # read function parent line
            mo = self._cg_parent_re.match(line)
            if not mo:
                sys.stderr.write('warning: unrecognized call graph entry (1): %r\n' % line)
            else:
                parent = self.translate(mo)
                if parent.name != '<spontaneous>':
                    parents.append(parent)

        # read primary line
        mo = self._cg_primary_re.match(line)
        if not mo:
            sys.stderr.write('warning: unrecognized call graph entry (2): %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:
                sys.stderr.write('warning: unrecognized call graph entry (3): %r\n' % line)
            else:
                child = self.translate(mo)
                if child.name != '<spontaneous>':
                    children.append(child)

        if function.name != '<spontaneous>':
            function.parents = parents
            function.children = children

            self.functions[function.index] = function

    def parse_cycle_entry(self, lines):

        # Process the parents that were not there in gprof format.
        parents = []
        while True:
            if not lines:
                sys.stderr.write('warning: unexpected end of cycle entry\n')
                return
            line = lines.pop(0)
            if line.startswith('['):
                break
            mo = self._cg_parent_re.match(line)
            if not mo:
                sys.stderr.write('warning: unrecognized call graph entry (6): %r\n' % line)
            else:
                parent = self.translate(mo)
                if parent.name != '<spontaneous>':
                    parents.append(parent)

        # read cycle header line
        mo = self._cg_cycle_header_re.match(line)
        if not mo:
            sys.stderr.write('warning: unrecognized call graph entry (4): %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 (5): %r\n' % line)
                continue
            call = self.translate(mo)
            cycle.functions.append(call)

        cycle.parents = parents
        self.cycles[cycle.cycle] = cycle

    def parse_cg_entry(self, lines):
        if any("as a whole" in linelooper for linelooper in lines):
            self.parse_cycle_entry(lines)
        else:
            self.parse_function_entry(lines)

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

        # skip call graph header
        line = self.readline()
        while self._cg_header_re.match(line):
            line = self.readline()

        # process call graph entries
        entry_lines = []
        # An EOF in readline terminates the program without returning.
        while not self._cg_footer_re.match(line):
            if line.isspace():
                self.parse_cg_entry(entry_lines)
                entry_lines = []
            else:
                entry_lines.append(line)
            line = self.readline()

    def parse(self):
        sys.stderr.write('warning: for axe format, edge weights are unreliable estimates derived from function total times.\n')
        self.parse_cg()
        self.fp.close()

        profile = Profile()
        profile[TIME] = 0.0

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

        for entry in self.functions.values():
            # populate the function
            function = Function(entry.index, entry.name)
            function[TIME] = entry.self
            function[TOTAL_TIME_RATIO] = entry.percentage_time / 100.0

            # populate the function calls
            for child in entry.children:
                call = Call(child.index)
                # The following bogus value affects only the weighting of
                # the calls.
                call[TOTAL_TIME_RATIO] = function[TOTAL_TIME_RATIO]

                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
                    # FIXME: Is this applicable?
                    missing = Function(child.index, child.name)
                    function[TIME] = 0.0
                    profile.add_function(missing)

                function.add_call(call)

            profile.add_function(function)

            if entry.cycle is not None:
                try:
                    cycle = cycles[entry.cycle]
                except KeyError:
                    sys.stderr.write('warning: <cycle %u as a whole> entry missing\n' % entry.cycle)
                    cycle = Cycle()
                    cycles[entry.cycle] = cycle
                cycle.add_function(function)

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

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

        # Compute derived events.
        profile.validate()
        profile.ratio(TIME_RATIO, TIME)
        # Lacking call counts, fake call ratios based on total times.
        profile.call_ratios(TOTAL_TIME_RATIO)
        # The TOTAL_TIME_RATIO of functions is already set.  Propagate that
        # total time to the calls.  (TOTAL_TIME is neither set nor used.)
        for function in profile.functions.values():
            for call in function.calls.values():
                if call.ratio is not None:
                    callee = profile.functions[call.callee_id]
                    call[TOTAL_TIME_RATIO] = call.ratio * callee[TOTAL_TIME_RATIO]

        return profile


class CallgrindParser(LineParser):
    """Parser for valgrind's callgrind tool.

    See also:
    - https://valgrind.org/docs/manual/cl-format.html
    """

    _call_re = re.compile(r'^calls=\s*(\d+)\s+((\d+|\+\d+|-\d+|\*)\s+)+$')

    def __init__(self, infile):
        LineParser.__init__(self, infile)

        # Textual positions
        self.position_ids = {}
        self.positions = {}

        # Numeric positions
        self.num_positions = 1
        self.cost_positions = ['line']
        self.last_positions = [0]

        # Events
        self.num_events = 0
        self.cost_events = []

        self.profile = Profile()
        self.profile[SAMPLES] = 0

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

        self.parse_key('version')
        self.parse_key('creator')
        while self.parse_part():
            pass
        if not self.eof():
            sys.stderr.write('warning: line %u: unexpected line\n' % self.line_no)
            sys.stderr.write('%s\n' % self.lookahead())

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

        return self.profile

    def parse_part(self):
        if not self.parse_header_line():
            return False
        while self.parse_header_line():
            pass
        if not self.parse_body_line():
            return False
        while self.parse_body_line():
            pass
        return True

    def parse_header_line(self):
        return \
            self.parse_empty() or \
            self.parse_comment() or \
            self.parse_part_detail() or \
            self.parse_description() or \
            self.parse_event_specification() or \
            self.parse_cost_line_def() or \
            self.parse_cost_summary()

    _detail_keys = set(('cmd', 'pid', 'thread', 'part'))

    def parse_part_detail(self):
        return self.parse_keys(self._detail_keys)

    def parse_description(self):
        return self.parse_key('desc') is not None

    def parse_event_specification(self):
        event = self.parse_key('event')
        if event is None:
            return False
        return True

    def parse_cost_line_def(self):
        pair = self.parse_keys(('events', 'positions'))
        if pair is None:
            return False
        key, value = pair
        items = value.split()
        if key == 'events':
            self.num_events = len(items)
            self.cost_events = items
        if key == 'positions':
            self.num_positions = len(items)
            self.cost_positions = items
            self.last_positions = [0]*self.num_positions
        return True

    def parse_cost_summary(self):
        pair = self.parse_keys(('summary', 'totals'))
        if pair is None:
            return False
        return True

    def parse_body_line(self):
        return \
            self.parse_empty() or \
            self.parse_comment() or \
            self.parse_cost_line() or \
            self.parse_position_spec() or \
            self.parse_association_spec()

    __subpos_re = r'(0x[0-9a-fA-F]+|\d+|\+\d+|-\d+|\*)'
    _cost_re = re.compile(r'^' +
        __subpos_re + r'( +' + __subpos_re + r')*' +
        r'( +\d+)*' +
    '$')

    def parse_cost_line(self, calls=None):
        line = self.lookahead().rstrip()
        mo = self._cost_re.match(line)
        if not mo:
            return False

        function = self.get_function()

        if calls is None:
            # Unlike other aspects, call object (cob) is relative not to the
            # last call object, but to the caller's object (ob), so try to
            # update it when processing a functions cost line
            try:
                self.positions['cob'] = self.positions['ob']
            except KeyError:
                pass

        values = line.split()
        assert len(values) <= self.num_positions + self.num_events

        positions = values[0 : self.num_positions]
        events = values[self.num_positions : ]
        events += ['0']*(self.num_events - len(events))

        for i in range(self.num_positions):
            position = positions[i]
            if position == '*':
                position = self.last_positions[i]
            elif position[0] in '-+':
                position = self.last_positions[i] + int(position)
            elif position.startswith('0x'):
                position = int(position, 16)
            else:
                position = int(position)
            self.last_positions[i] = position

        events = [float(event) for event in events]

        if calls is None:
            function[SAMPLES] += events[0]
            self.profile[SAMPLES] += events[0]
        else:
            callee = self.get_callee()
            callee.called += calls

            try:
                call = function.calls[callee.id]
            except KeyError:
                call = Call(callee.id)
                call[CALLS] = calls
                call[SAMPLES2] = events[0]
                function.add_call(call)
            else:
                call[CALLS] += calls
                call[SAMPLES2] += events[0]

        self.consume()
        return True

    def parse_association_spec(self):
        line = self.lookahead()
        if not line.startswith('calls='):
            return False

        _, values = line.split('=', 1)
        values = values.strip().split()
        calls = int(values[0])
        call_position = values[1:]
        self.consume()

        self.parse_cost_line(calls)

        return True

    _position_re = re.compile(r'^(?P<position>[cj]?(?:ob|fl|fi|fe|fn))=\s*(?:\((?P<id>\d+)\))?(?:\s*(?P<name>.+))?')

    _position_table_map = {
        'ob': 'ob',
        'fl': 'fl',
        'fi': 'fl',
        'fe': 'fl',
        'fn': 'fn',
        'cob': 'ob',
        'cfl': 'fl',
        'cfi': 'fl',
        'cfe': 'fl',
        'cfn': 'fn',
        'jfi': 'fl',
    }

    _position_map = {
        'ob': 'ob',
        'fl': 'fl',
        'fi': 'fl',
        'fe': 'fl',
        'fn': 'fn',
        'cob': 'cob',
        'cfl': 'cfl',
        'cfi': 'cfl',
        'cfe': 'cfl',
        'cfn': 'cfn',
        'jfi': 'jfi',
    }

    def parse_position_spec(self):
        line = self.lookahead()

        if line.startswith('jump=') or line.startswith('jcnd='):
            self.consume()
            return True

        mo = self._position_re.match(line)
        if not mo:
            return False

        position, id, name = mo.groups()
        if id:
            table = self._position_table_map[position]
            if name:
                self.position_ids[(table, id)] = name
            else:
                name = self.position_ids.get((table, id), '')
        self.positions[self._position_map[position]] = name

        self.consume()
        return True

    def parse_empty(self):
        if self.eof():
            return False
        line = self.lookahead()
        if line.strip():
            return False
        self.consume()
        return True

    def parse_comment(self):
        line = self.lookahead()
        if not line.startswith('#'):
            return False
        self.consume()
        return True

    _key_re = re.compile(r'^(\w+):')

    def parse_key(self, key):
        pair = self.parse_keys((key,))
        if not pair:
            return None
        key, value = pair
        return value

    def parse_keys(self, keys):
        line = self.lookahead()
        mo = self._key_re.match(line)
        if not mo:
            return None
        key, value = line.split(':', 1)
        if key not in keys:
            return None
        value = value.strip()
        self.consume()
        return key, value

    def make_function(self, module, filename, name):
        # FIXME: module and filename are not being tracked reliably
        #id = '|'.join((module, filename, name))
        id = name
        try:
            function = self.profile.functions[id]
        except KeyError:
            function = Function(id, name)
            if module:
                function.module = os.path.basename(module)
            function[SAMPLES] = 0
            function.called = 0
            self.profile.add_function(function)
        return function

    def get_function(self):
        module = self.positions.get('ob', '')
        filename = self.positions.get('fl', '')
        function = self.positions.get('fn', '')
        return self.make_function(module, filename, function)

    def get_callee(self):
        module = self.positions.get('cob', '')
        filename = self.positions.get('cfi', '')
        function = self.positions.get('cfn', '')
        return self.make_function(module, filename, function)

    def readline(self):
        # Override LineParser.readline to ignore comment lines
        while True:
            LineParser.readline(self)
            if self.eof() or not self.lookahead().startswith('#'):
                break


class PerfParser(LineParser):
    """Parser for linux perf callgraph output.

    It expects output generated with

        perf record -g
        perf script | gprof2dot.py --format=perf
    """

    def __init__(self, infile):
        LineParser.__init__(self, infile)
        self.profile = Profile()

    def readline(self):
        # Override LineParser.readline to ignore comment lines
        while True:
            LineParser.readline(self)
            if self.eof() or not self.lookahead().startswith('#'):
                break

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

        profile = self.profile
        profile[SAMPLES] = 0
        while not self.eof():
            self.parse_event()

        # compute derived data
        profile.validate()
        profile.find_cycles()
        profile.ratio(TIME_RATIO, SAMPLES)
        profile.call_ratios(SAMPLES2)
        if totalMethod == "callratios":
            # Heuristic approach.  TOTAL_SAMPLES is unused.
            profile.integrate(TOTAL_TIME_RATIO, TIME_RATIO)
        elif totalMethod == "callstacks":
            # Use the actual call chains for functions.
            profile[TOTAL_SAMPLES] = profile[SAMPLES]
            profile.ratio(TOTAL_TIME_RATIO, TOTAL_SAMPLES)
            # Then propagate that total time to the calls.
            for function in profile.functions.values():
                for call in function.calls.values():
                    if call.ratio is not None:
                        callee = profile.functions[call.callee_id]
                        call[TOTAL_TIME_RATIO] = call.ratio * callee[TOTAL_TIME_RATIO]
        else:
            assert False

        return profile

    def parse_event(self):
        if self.eof():
            return

        line = self.consume()
        assert line

        callchain = self.parse_callchain()
        if not callchain:
            return

        callee = callchain[0]
        callee[SAMPLES] += 1
        self.profile[SAMPLES] += 1

        for caller in callchain[1:]:
            try:
                call = caller.calls[callee.id]
            except KeyError:
                call = Call(callee.id)
                call[SAMPLES2] = 1
                caller.add_call(call)
            else:
                call[SAMPLES2] += 1

            callee = caller

        # Increment TOTAL_SAMPLES only once on each function.
        stack = set(callchain)
        for function in stack:
            function[TOTAL_SAMPLES] += 1

    def parse_callchain(self):
        callchain = []
        while self.lookahead():
            function = self.parse_call()
            if function is None:
                break
            callchain.append(function)
        if self.lookahead() == '':
            self.consume()
        return callchain

    call_re = re.compile(r'^\s+(?P<address>[0-9a-fA-F]+)\s+(?P<symbol>.*)\s+\((?P<module>.*)\)$')
    addr2_re = re.compile(r'\+0x[0-9a-fA-F]+$')

    def parse_call(self):
        line = self.consume()
        mo = self.call_re.match(line)
        assert mo
        if not mo:
            return None

        function_name = mo.group('symbol')

        # If present, amputate program counter from function name.
        if function_name:
            function_name = re.sub(self.addr2_re, '', function_name)

        if not function_name or function_name == '[unknown]':
            function_name = mo.group('address')

        module = mo.group('module')

        function_id = function_name + ':' + module

        try:
            function = self.profile.functions[function_id]
        except KeyError:
            function = Function(function_id, function_name)
            function.module = os.path.basename(module)
            function[SAMPLES] = 0
            function[TOTAL_SAMPLES] = 0
            self.profile.add_function(function)

        return function


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

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

    _fields_re = {
        'samples': r'(\d+)',
        '%': r'(\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.values():
            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.values():
            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.values():
                total_callee_samples += _callee.samples

            for _callee in _callees.values():
                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(mo.group(1))
        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 HProfParser(LineParser):
    """Parser for java hprof output

    See also:
    - http://java.sun.com/developer/technicalArticles/Programming/HPROF.html
    """

    trace_re = re.compile(r'\t(.*)\((.*):(.*)\)')
    trace_id_re = re.compile(r'^TRACE (\d+):$')

    def __init__(self, infile):
        LineParser.__init__(self, infile)
        self.traces = {}
        self.samples = {}

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

        while not self.lookahead().startswith('------'): self.consume()
        while not self.lookahead().startswith('TRACE '): self.consume()

        self.parse_traces()

        while not self.lookahead().startswith('CPU'):
            self.consume()

        self.parse_samples()

        # populate the profile
        profile = Profile()
        profile[SAMPLES] = 0

        functions = {}

        # build up callgraph
        for id, trace in self.traces.items():
            if not id in self.samples: continue
            mtime = self.samples[id][0]
            last = None

            for func, file, line in trace:
                if not func in functions:
                    function = Function(func, func)
                    function[SAMPLES] = 0
                    profile.add_function(function)
                    functions[func] = function

                function = functions[func]
                # allocate time to the deepest method in the trace
                if not last:
                    function[SAMPLES] += mtime
                    profile[SAMPLES] += mtime
                else:
                    c = function.get_call(last)
                    c[SAMPLES2] += mtime

                last = func

        # 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_traces(self):
        while self.lookahead().startswith('TRACE '):
            self.parse_trace()

    def parse_trace(self):
        l = self.consume()
        mo = self.trace_id_re.match(l)
        tid = mo.group(1)
        last = None
        trace = []

        while self.lookahead().startswith('\t'):
            l = self.consume()
            match = self.trace_re.search(l)
            if not match:
                #sys.stderr.write('Invalid line: %s\n' % l)
                break
            else:
                function_name, file, line = match.groups()
                trace += [(function_name, file, line)]

        self.traces[int(tid)] = trace

    def parse_samples(self):
        self.consume()
        self.consume()

        while not self.lookahead().startswith('CPU'):
            rank, percent_self, percent_accum, count, traceid, method = self.lookahead().split()
            self.samples[int(traceid)] = (int(count), method)
            self.consume()


class SysprofParser(XmlParser):

    def __init__(self, stream):
        XmlParser.__init__(self, stream)

    def parse(self):
        objects = {}
        nodes = {}

        self.element_start('profile')
        while self.token.type == XML_ELEMENT_START:
            if self.token.name_or_data == 'objects':
                assert not objects
                objects = self.parse_items('objects')
            elif self.token.name_or_data == 'nodes':
                assert not nodes
                nodes = self.parse_items('nodes')
            else:
                self.parse_value(self.token.name_or_data)
        self.element_end('profile')

        return self.build_profile(objects, nodes)

    def parse_items(self, name):
        assert name[-1] == 's'
        items = {}
        self.element_start(name)
        while self.token.type == XML_ELEMENT_START:
            id, values = self.parse_item(name[:-1])
            assert id not in items
            items[id] = values
        self.element_end(name)
        return items

    def parse_item(self, name):
        attrs = self.element_start(name)
        id = int(attrs['id'])
        values = self.parse_values()
        self.element_end(name)
        return id, values

    def parse_values(self):
        values = {}
        while self.token.type == XML_ELEMENT_START:
            name = self.token.name_or_data
            value = self.parse_value(name)
            assert name not in values
            values[name] = value
        return values

    def parse_value(self, tag):
        self.element_start(tag)
        value = self.character_data()
        self.element_end(tag)
        if value.isdigit():
            return int(value)
        if value.startswith('"') and value.endswith('"'):
            return value[1:-1]
        return value

    def build_profile(self, objects, nodes):
        profile = Profile()

        profile[SAMPLES] = 0
        for id, object in objects.items():
            # Ignore fake objects (process names, modules, "Everything", "kernel", etc.)
            if object['self'] == 0:
                continue

            function = Function(id, object['name'])
            function[SAMPLES] = object['self']
            profile.add_function(function)
            profile[SAMPLES] += function[SAMPLES]

        for id, node in nodes.items():
            # Ignore fake calls
            if node['self'] == 0:
                continue

            # Find a non-ignored parent
            parent_id = node['parent']
            while parent_id != 0:
                parent = nodes[parent_id]
                caller_id = parent['object']
                if objects[caller_id]['self'] != 0:
                    break
                parent_id = parent['parent']
            if parent_id == 0:
                continue

            callee_id = node['object']

            assert objects[caller_id]['self']
            assert objects[callee_id]['self']

            function = profile.functions[caller_id]

            samples = node['self']
            try:
                call = function.calls[callee_id]
            except KeyError:
                call = Call(callee_id)
                call[SAMPLES2] = samples
                function.add_call(call)
            else:
                call[SAMPLES2] += samples

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

        return profile


class XPerfParser(Parser):
    """Parser for CSVs generated by XPerf, from Microsoft Windows Performance Tools.
    """

    def __init__(self, stream):
        Parser.__init__(self)
        self.stream = stream
        self.profile = Profile()
        self.profile[SAMPLES] = 0
        self.column = {}

    def parse(self):
        import csv
        reader = csv.reader(
            self.stream,
            delimiter = ',',
            quotechar = None,
            escapechar = None,
            doublequote = False,
            skipinitialspace = True,
            lineterminator = '\r\n',
            quoting = csv.QUOTE_NONE)
        header = True
        for row in reader:
            if header:
                self.parse_header(row)
                header = False
            else:
                self.parse_row(row)

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

        return self.profile

    def parse_header(self, row):
        for column in range(len(row)):
            name = row[column]
            assert name not in self.column
            self.column[name] = column

    def parse_row(self, row):
        fields = {}
        for name, column in self.column.items():
            value = row[column]
            for factory in int, float:
                try:
                    value = factory(value)
                except ValueError:
                    pass
                else:
                    break
            fields[name] = value

        process = fields['Process Name']
        symbol = fields['Module'] + '!' + fields['Function']
        weight = fields['Weight']
        count = fields['Count']

        if process == 'Idle':
            return

        function = self.get_function(process, symbol)
        function[SAMPLES] += weight * count
        self.profile[SAMPLES] += weight * count

        stack = fields['Stack']
        if stack != '?':
            stack = stack.split('/')
            assert stack[0] == '[Root]'
            if stack[-1] != symbol:
                # XXX: some cases the sampled function does not appear in the stack
                stack.append(symbol)
            caller = None
            for symbol in stack[1:]:
                callee = self.get_function(process, symbol)
                if caller is not None:
                    try:
                        call = caller.calls[callee.id]
                    except KeyError:
                        call = Call(callee.id)
                        call[SAMPLES2] = count
                        caller.add_call(call)
                    else:
                        call[SAMPLES2] += count
                caller = callee

    def get_function(self, process, symbol):
        function_id = process + '!' + symbol

        try:
            function = self.profile.functions[function_id]
        except KeyError:
            module, name = symbol.split('!', 1)
            function = Function(function_id, name)
            function.process = process
            function.module = module
            function[SAMPLES] = 0
            self.profile.add_function(function)

        return function


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

    See also:
    - http://www.codersnotes.com/sleepy/
    - http://sleepygraph.sourceforge.net/
    """

    stdinInput = False

    def __init__(self, filename):
        Parser.__init__(self)

        from zipfile import ZipFile

        self.database = ZipFile(filename)

        self.symbols = {}
        self.calls = {}

        self.profile = Profile()

    _symbol_re = re.compile(
        r'^(?P<id>\w+)' +
        r'\s+"(?P<module>[^"]*)"' +
        r'\s+"(?P<procname>[^"]*)"' +
        r'\s+"(?P<sourcefile>[^"]*)"' +
        r'\s+(?P<sourceline>\d+)$'
    )

    def openEntry(self, name):
        # Some versions of verysleepy use lowercase filenames
        for database_name in self.database.namelist():
            if name.lower() == database_name.lower():
                name = database_name
                break

        return self.database.open(name, 'r')

    def parse_symbols(self):
        for line in self.openEntry('Symbols.txt'):
            line = line.decode('UTF-8').rstrip('\r\n')

            mo = self._symbol_re.match(line)
            if mo:
                symbol_id, module, procname, sourcefile, sourceline = mo.groups()

                function_id = ':'.join([module, procname])

                try:
                    function = self.profile.functions[function_id]
                except KeyError:
                    function = Function(function_id, procname)
                    function.module = module
                    function[SAMPLES] = 0
                    self.profile.add_function(function)

                self.symbols[symbol_id] = function

    def parse_callstacks(self):
        for line in self.openEntry('Callstacks.txt'):
            line = line.decode('UTF-8').rstrip('\r\n')

            fields = line.split()
            samples = float(fields[0])
            callstack = fields[1:]

            callstack = [self.symbols[symbol_id] for symbol_id in callstack]

            callee = callstack[0]

            callee[SAMPLES] += samples
            self.profile[SAMPLES] += samples

            for caller in callstack[1:]:
                try:
                    call = caller.calls[callee.id]
                except KeyError:
                    call = Call(callee.id)
                    call[SAMPLES2] = samples
                    caller.add_call(call)
                else:
                    call[SAMPLES2] += samples

                callee = caller

    def parse(self):
        profile = self.profile
        profile[SAMPLES] = 0

        self.parse_symbols()
        self.parse_callstacks()

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

        return profile


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

    stdinInput = False
    multipleInput = True

    def __init__(self, *filename):
        import pstats
        try:
            self.stats = pstats.Stats(*filename)
        except ValueError:
            sys.stderr.write('error: failed to load %s, maybe they are generated by different python version?\n' % ', '.join(filename))
            sys.exit(1)
        self.profile = Profile()
        self.function_ids = {}

    def get_function_name(self, key):
        filename, line, name = key
        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)
            function.filename = key[0]
            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.items():
            callee = self.get_function(fn)
            callee.called = 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.items():
                caller = self.get_function(fn)
                call = Call(callee.id)
                if isinstance(value, tuple):
                    for i in range(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)

        if False:
            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 DtraceParser(LineParser):
    """Parser for linux perf callgraph output.

    It expects output generated with

        # Refer to https://github.com/brendangregg/FlameGraph#dtrace
        # 60 seconds of user-level stacks, including time spent in-kernel, for PID 12345 at 97 Hertz
        sudo dtrace -x ustackframes=100 -n 'profile-97 /pid == 12345/ { @[ustack()] = count(); } tick-60s { exit(0); }' -o out.user_stacks

        # The dtrace output
        gprof2dot.py -f dtrace out.user_stacks

        # Notice: sometimes, the dtrace outputs format may be latin-1, and gprof2dot will fail to parse it.
        # To solve this problem, you should use iconv to convert to UTF-8 explicitly.
        # TODO: add an encoding flag to tell gprof2dot how to decode the profile file.
        iconv -f ISO-8859-1 -t UTF-8 out.user_stacks | gprof2dot.py -f dtrace
    """

    def __init__(self, infile):
        LineParser.__init__(self, infile)
        self.profile = Profile()

    def readline(self):
        # Override LineParser.readline to ignore comment lines
        while True:
            LineParser.readline(self)
            if self.eof():
                break

            line = self.lookahead().strip()
            if line.startswith('CPU'):
                # The format likes:
                # CPU     ID                    FUNCTION:NAME
                #   1  29684                        :tick-60s
                # Skip next line
                LineParser.readline(self)
            elif not line == '':
                break


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

        profile = self.profile
        profile[SAMPLES] = 0
        while not self.eof():
            self.parse_event()

        # compute derived data
        profile.validate()
        profile.find_cycles()
        profile.ratio(TIME_RATIO, SAMPLES)
        profile.call_ratios(SAMPLES2)
        if totalMethod == "callratios":
            # Heuristic approach.  TOTAL_SAMPLES is unused.
            profile.integrate(TOTAL_TIME_RATIO, TIME_RATIO)
        elif totalMethod == "callstacks":
            # Use the actual call chains for functions.
            profile[TOTAL_SAMPLES] = profile[SAMPLES]
            profile.ratio(TOTAL_TIME_RATIO, TOTAL_SAMPLES)
            # Then propagate that total time to the calls.
            for function in profile.functions.values():
                for call in function.calls.values():
                    if call.ratio is not None:
                        callee = profile.functions[call.callee_id]
                        call[TOTAL_TIME_RATIO] = call.ratio * callee[TOTAL_TIME_RATIO]
        else:
            assert False

        return profile

    def parse_event(self):
        if self.eof():
            return

        callchain, count = self.parse_callchain()
        if not callchain:
            return

        callee = callchain[0]
        callee[SAMPLES] += count
        self.profile[SAMPLES] += count

        for caller in callchain[1:]:
            try:
                call = caller.calls[callee.id]
            except KeyError:
                call = Call(callee.id)
                call[SAMPLES2] = count
                caller.add_call(call)
            else:
                call[SAMPLES2] += count

            callee = caller

        # Increment TOTAL_SAMPLES only once on each function.
        stack = set(callchain)
        for function in stack:
            function[TOTAL_SAMPLES] += count


    def parse_callchain(self):
        callchain = []
        count = 0
        while self.lookahead():
            function, count = self.parse_call()
            if function is None:
                break
            callchain.append(function)
        return callchain, count

    call_re = re.compile(r'^\s+(?P<module>.*)`(?P<symbol>.*)')
    addr2_re = re.compile(r'\+0x[0-9a-fA-F]+$')

    def parse_call(self):
        line = self.consume()
        mo = self.call_re.match(line)
        if not mo:
            # The line must be the stack count
            return None, int(line.strip())

        function_name = mo.group('symbol')

        # If present, amputate program counter from function name.
        if function_name:
            function_name = re.sub(self.addr2_re, '', function_name)

        # if not function_name or function_name == '[unknown]':
        #     function_name = mo.group('address')

        module = mo.group('module')

        function_id = function_name + ':' + module

        try:
            function = self.profile.functions[function_id]
        except KeyError:
            function = Function(function_id, function_name)
            function.module = os.path.basename(module)
            function[SAMPLES] = 0
            function[TOTAL_SAMPLES] = 0
            self.profile.add_function(function)

        return function, None


class CollapseParser(LineParser):
    """Parser for the output of stackcollapse

    (from https://github.com/brendangregg/FlameGraph)
    """

    def __init__(self, infile):
        LineParser.__init__(self, infile)
        self.profile = Profile()

    def parse(self):
        profile = self.profile
        profile[SAMPLES] = 0

        self.readline()
        while not self.eof():
            self.parse_event()

        # compute derived data
        profile.validate()
        profile.find_cycles()
        profile.ratio(TIME_RATIO, SAMPLES)
        profile.call_ratios(SAMPLES2)
        if totalMethod == "callratios":
            # Heuristic approach.  TOTAL_SAMPLES is unused.
            profile.integrate(TOTAL_TIME_RATIO, TIME_RATIO)
        elif totalMethod == "callstacks":
            # Use the actual call chains for functions.
            profile[TOTAL_SAMPLES] = profile[SAMPLES]
            profile.ratio(TOTAL_TIME_RATIO, TOTAL_SAMPLES)
            # Then propagate that total time to the calls.
            for function in compat_itervalues(profile.functions):
                for call in compat_itervalues(function.calls):
                    if call.ratio is not None:
                        callee = profile.functions[call.callee_id]
                        call[TOTAL_TIME_RATIO] = call.ratio * callee[TOTAL_TIME_RATIO]
        else:
            assert False

        return profile

    def parse_event(self):
        line = self.consume()

        stack, count = line.rsplit(' ',maxsplit=1)
        count=int(count)
        self.profile[SAMPLES] += count

        calls = stack.split(';')
        functions = [self._make_function(call) for call in calls]

        functions[-1][SAMPLES] += count

        # TOTAL_SAMPLES excludes loops
        for func in set(functions):
            func[TOTAL_SAMPLES] += count

        # add call data
        callee = functions[-1]
        for caller in reversed(functions[:-1]):
            call = caller.calls.get(callee.id)
            if call is None:
                call = Call(callee.id)
                call[SAMPLES2] = 0
                caller.add_call(call)
            call[SAMPLES2] += count
            callee = caller

    call_re = re.compile(r'^(?P<func>[^ ]+) \((?P<file>.*):(?P<line>[0-9]+)\)$')

    def _make_function(self, call):
        """turn a call str into a Function

        takes a call site, as found between semicolons in the input, and returns
        a Function definition corresponding to that call site.
        """
        mo = self.call_re.match(call)
        if mo:
            name, module, line = mo.groups()
            func_id = "%s:%s" % (module, name)
        else:
            name = func_id = call
            module = None

        func = self.profile.functions.get(func_id)
        if func is None:
            func = Function(func_id, name)
            func.module = module
            func[SAMPLES] = 0
            func[TOTAL_SAMPLES] = 0
            self.profile.add_function(func)
        return func


formats = {
    "axe": AXEParser,
    "callgrind": CallgrindParser,
    "collapse": CollapseParser,
    "hprof": HProfParser,
    "json": JsonParser,
    "oprofile": OprofileParser,
    "perf": PerfParser,
    "prof": GprofParser,
    "pstats": PstatsParser,
    "sleepy": SleepyParser,
    "sysprof": SysprofParser,
    "xperf": XPerfParser,
    "dtrace": DtraceParser,
}


########################################################################
# Output


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",
            fontcolor = "white",
            nodestyle = "filled",
            minfontsize = 10.0,
            maxfontsize = 10.0,
            minpenwidth = 0.5,
            maxpenwidth = 4.0,
            gamma = 2.2,
            skew = 1.0):
        self.bgcolor = bgcolor
        self.mincolor = mincolor
        self.maxcolor = maxcolor
        self.fontname = fontname
        self.fontcolor = fontcolor
        self.nodestyle = nodestyle
        self.minfontsize = minfontsize
        self.maxfontsize = maxfontsize
        self.minpenwidth = minpenwidth
        self.maxpenwidth = maxpenwidth
        self.gamma = gamma
        self.skew = skew

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

    def graph_fontname(self):
        return self.fontname

    def graph_fontcolor(self):
        return self.fontcolor

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

    def node_fgcolor(self, weight):
        if self.nodestyle == "filled":
            return self.graph_bgcolor()
        else:
            return self.color(weight)

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

    def node_style(self):
        return self.nodestyle

    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

        if self.skew < 0:
            raise ValueError("Skew must be greater than 0")
        elif self.skew == 1.0:
            h = hmin + weight*(hmax - hmin)
            s = smin + weight*(smax - smin)
            l = lmin + weight*(lmax - lmin)
        else:
            base = self.skew
            h = hmin + ((hmax-hmin)*(-1.0 + (base ** weight)) / (base - 1.0))
            s = smin + ((smax-smin)*(-1.0 + (base ** weight)) / (base - 1.0))
            l = lmin + ((lmax-lmin)*(-1.0 + (base ** weight)) / (base - 1.0))

        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,
)

PRINT_COLORMAP = Theme(
    minfontsize = 18.0,
    maxfontsize = 30.0,
    fontcolor = "black",
    nodestyle = "solid",
    mincolor = (0.0, 0.0, 0.0), # black
    maxcolor = (0.0, 0.0, 0.0), # black
    minpenwidth = 0.1,
    maxpenwidth = 8.0,
)


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


def sorted_iteritems(d):
    # Used mostly for result reproducibility (while testing.)
    keys = list(d.keys())
    keys.sort()
    for key in keys:
        value = d[key]
        yield key, value


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

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

    strip = False
    wrap = False

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

    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

    show_function_events = [TOTAL_TIME_RATIO, TIME_RATIO]
    show_edge_events = [TOTAL_TIME_RATIO, CALLS]

    def graphs_compare(self, profile1, profile2, theme, options):
        self.begin_graph()

        fontname = theme.graph_fontname()
        fontcolor = theme.graph_fontcolor()
        nodestyle = theme.node_style()

        tolerance, only_slower, only_faster, color_by_difference = (
            options.tolerance, options.only_slower, options.only_faster, options.color_by_difference)
        self.attr('graph', fontname=fontname, ranksep=0.25, nodesep=0.125)
        self.attr('node', fontname=fontname, style=nodestyle, fontcolor=fontcolor, width=0, height=0)
        self.attr('edge', fontname=fontname)

        functions2 = {function.name: function for _, function in sorted_iteritems(profile2.functions)}

        for _, function1 in sorted_iteritems(profile1.functions):
            labels = []

            name = function1.name
            try:
                function2 = functions2[name]
                if self.wrap:
                    name = self.wrap_function_name(name)
                if color_by_difference:
                    min_diff, max_diff = min_max_difference(profile1, profile2)
                labels.append(name)
                weight_difference = 0
                shape = 'box'
                orientation = '0'
                for event in self.show_function_events:
                    if event in function1.events:
                        event1 = function1[event]
                        event2 = function2[event]

                        difference = abs(event1 - event2) * 100

                        if event == TOTAL_TIME_RATIO:
                            weight_difference = difference
                            if difference >= tolerance:
                                if event2 > event1 and not only_faster:
                                    shape = 'cds'
                                    label = (f'{event.format(event1)} +'
                                             f' {round_difference(difference, tolerance)}%')
                                elif event2 < event1 and not only_slower:
                                    orientation = "90"
                                    shape = 'cds'
                                    label = (f'{event.format(event1)} - '
                                             f'{round_difference(difference, tolerance)}%')
                                else:
                                    # protection to not color by difference if we choose to show only_faster/only_slower
                                    weight_difference = 0
                                    label = event.format(function1[event])
                            else:
                                weight_difference = 0
                                label = event.format(function1[event])
                        else:
                            if difference >= tolerance:
                                if event2 > event1:
                                    label = (f'{event.format(event1)} +'
                                             f' {round_difference(difference, tolerance)}%')
                                elif event2 < event1:
                                    label = (f'{event.format(event1)} - '
                                             f'{round_difference(difference, tolerance)}%')
                            else:
                                label = event.format(function1[event])

                        labels.append(label)
                        if function1.called is not None:
                            labels.append(f"{function1.called} {MULTIPLICATION_SIGN}/ {function2.called} {MULTIPLICATION_SIGN}")

            except KeyError:
                shape = 'box'
                orientation = '0'
                weight_difference = 0
                if function1.process is not None:
                    labels.append(function1.process)
                if function1.module is not None:
                    labels.append(function1.module)

                if self.strip:
                    function_name = function1.stripped_name()
                else:
                    function_name = function1.name
                if color_by_difference:
                    min_diff, max_diff = 0, 0

                # dot can't parse quoted strings longer than YY_BUF_SIZE, which
                # defaults to 16K. But some annotated C++ functions (e.g., boost,
                # https://github.com/jrfonseca/gprof2dot/issues/30) can exceed that
                MAX_FUNCTION_NAME = 4096
                if len(function_name) >= MAX_FUNCTION_NAME:
                    sys.stderr.write('warning: truncating function name with %u chars (%s)\n' % (len(function_name), function_name[:32] + '...'))
                    function_name = function_name[:MAX_FUNCTION_NAME - 1] + chr(0x2026)

                if self.wrap:
                    function_name = self.wrap_function_name(function_name)
                labels.append(function_name)

                for event in self.show_function_events:
                    if event in function1.events:
                        label = event.format(function1[event])
                        labels.append(label)
                if function1.called is not None:
                    labels.append("%u%s" % (function1.called, MULTIPLICATION_SIGN))

            if color_by_difference and weight_difference:
                # min and max is calculated whe color_by_difference is true
                weight = rescale_difference(weight_difference, min_diff, max_diff)

            elif function1.weight is not None and not color_by_difference:
                weight = function1.weight
            else:
                weight = 0.0

            label = '\n'.join(labels)

            self.node(function1.id,
                      label=label,
                      orientation=orientation,
                      color=self.color(theme.node_bgcolor(weight)),
                      shape=shape,
                      fontcolor=self.color(theme.node_fgcolor(weight)),
                      fontsize="%f" % theme.node_fontsize(weight),
                      tooltip=function1.filename,
                      )

            calls2 = {call.callee_id: call for _, call in sorted_iteritems(function2.calls)}
            functions_by_id1 = {function.id: function for _, function in sorted_iteritems(profile1.functions)}

            for _, call1 in sorted_iteritems(function1.calls):
                labels = []
                try:
                    # if profiles do not have identical setups, callee_id will not be identical either
                    call_id1 = call1.callee_id
                    call_name = functions_by_id1[call_id1].name
                    call_id2 = functions2[call_name].id
                    call2 = calls2[call_id2]
                    for event in self.show_edge_events:
                        if event in call1.events:
                            label = f'{event.format(call1[event])} / {event.format(call2[event])}'
                            labels.append(label)
                except KeyError:
                    for event in self.show_edge_events:
                        if event in call1.events:
                            label = f'{event.format(call1[event])}'
                            labels.append(label)

                weight = 0 if color_by_difference else call1.weight
                label = '\n'.join(labels)
                self.edge(function1.id, call1.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 graph(self, profile, theme):
        self.begin_graph()

        fontname = theme.graph_fontname()
        fontcolor = theme.graph_fontcolor()
        nodestyle = theme.node_style()

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

        for _, function in sorted_iteritems(profile.functions):
            labels = []
            if function.process is not None:
                labels.append(function.process)
            if function.module is not None:
                labels.append(function.module)

            if self.strip:
                function_name = function.stripped_name()
            else:
                function_name = function.name

            # dot can't parse quoted strings longer than YY_BUF_SIZE, which
            # defaults to 16K. But some annotated C++ functions (e.g., boost,
            # https://github.com/jrfonseca/gprof2dot/issues/30) can exceed that
            MAX_FUNCTION_NAME = 4096
            if len(function_name) >= MAX_FUNCTION_NAME:
                sys.stderr.write('warning: truncating function name with %u chars (%s)\n' % (len(function_name), function_name[:32] + '...'))
                function_name = function_name[:MAX_FUNCTION_NAME - 1] + chr(0x2026)

            if self.wrap:
                function_name = self.wrap_function_name(function_name)
            labels.append(function_name)

            for event in self.show_function_events:
                if event in function.events:
                    label = event.format(function[event])
                    labels.append(label)
            if function.called is not None:
                labels.append("%u%s" % (function.called, MULTIPLICATION_SIGN))

            if function.weight is not None:
                weight = function.weight
            else:
                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),
                tooltip = function.filename,
            )

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

                labels = []
                for event in self.show_edge_events:
                    if event in call.events:
                        label = event.format(call[event])
                        labels.append(label)

                if call.weight is not None:
                    weight = call.weight
                elif callee.weight is not None:
                    weight = callee.weight
                else:
                    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')
        # Work-around graphviz bug[1]: unnamed graphs have "%3" tooltip in SVG
        # output. The bug was fixed upstream, but graphviz shipped in recent
        # Linux distros (for example, Ubuntu 24.04) still has the bug.
        # [1] https://gitlab.com/graphviz/graphviz/-/issues/1376
        self.write('\ttooltip=" "\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.node_id(node)
        self.attr_list(attrs)
        self.write(";\n")

    def edge(self, src, dst, **attrs):
        self.write("\t")
        self.node_id(src)
        self.write(" -> ")
        self.node_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 sorted_iteritems(attrs):
            if value is None:
                continue
            if first:
                first = False
            else:
                self.write(", ")
            assert isinstance(name, str)
            assert name.isidentifier()
            self.write(name)
            self.write('=')
            self.id(value)
        self.write(']')

    def node_id(self, id):
        # Node IDs need to be unique (can't be truncated) but dot doesn't allow
        # IDs longer than 16384 characters, so use an hash instead for the huge
        # C++ symbols that can arise, as seen in
        # https://github.com/jrfonseca/gprof2dot/issues/99
        if isinstance(id, str) and len(id) > 1024:
            id = '_' + hashlib.sha1(id.encode('utf-8'), usedforsecurity=False).hexdigest()
        self.id(id)

    def id(self, id):
        if isinstance(id, (int, float)):
            s = str(id)
        elif isinstance(id, str):
            if id.isalnum() and not id.startswith('0x'):
                s = id
            else:
                s = self.escape(id)
        else:
            raise TypeError
        self.write(s)

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

        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.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)



########################################################################
# Main program


def naturalJoin(values):
    if len(values) >= 2:
        return ', '.join(values[:-1]) + ' or ' + values[-1]

    else:
        return ''.join(values)


def main(argv=sys.argv[1:]):
    """Main program."""

    global totalMethod, timeFormat

    formatNames = list(formats.keys())
    formatNames.sort()

    themeNames = list(themes.keys())
    themeNames.sort()

    labelNames = list(labels.keys())
    labelNames.sort()

    optparser = optparse.OptionParser(
        usage="\n\t%prog [options] [file] ...")
    optparser.add_option(
        '-o', '--output', metavar='FILE',
        type="string", dest="output",
        help="output filename [stdout]")
    optparser.add_option(
        '-n', '--node-thres', metavar='PERCENTAGE',
        type="float", dest="node_thres", default=0.5,
        help="eliminate nodes below this threshold [default: %default]")
    optparser.add_option(
        '-e', '--edge-thres', metavar='PERCENTAGE',
        type="float", dest="edge_thres", default=0.1,
        help="eliminate edges below this threshold [default: %default]")
    optparser.add_option(
        '-f', '--format',
        type="choice", choices=formatNames,
        dest="format", default="prof",
        help="profile format: %s [default: %%default]" % naturalJoin(formatNames))
    optparser.add_option(
        '--total',
        type="choice", choices=('callratios', 'callstacks'),
        dest="totalMethod", default=totalMethod,
        help="preferred method of calculating total time: callratios or callstacks (currently affects only perf format) [default: %default]")
    optparser.add_option(
        '-c', '--colormap',
        type="choice", choices=themeNames,
        dest="theme", default="color",
        help="color map: %s [default: %%default]" % naturalJoin(themeNames))
    optparser.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")
    optparser.add_option(
        '--color-nodes-by-selftime',
        action="store_true",
        dest="color_nodes_by_selftime", default=False,
        help="color nodes by self time, rather than by total time (sum of self and descendants)")
    optparser.add_option(
        '--colour-nodes-by-selftime',
        action="store_true",
        dest="color_nodes_by_selftime",
        help=optparse.SUPPRESS_HELP)
    optparser.add_option(
        '-w', '--wrap',
        action="store_true",
        dest="wrap", default=False,
        help="wrap function names")
    optparser.add_option(
        '--show-samples',
        action="store_true",
        dest="show_samples", default=False,
        help="show function samples")
    optparser.add_option(
        '--time-format',
        default=timeFormat,
        help="format to use for showing time values [default: %default]")
    optparser.add_option(
        '--node-label', metavar='MEASURE',
        type='choice', choices=labelNames,
        action='append',
        dest='node_labels',
        help="measurements to on show the node (can be specified multiple times): %s [default: %s]" % (
            naturalJoin(labelNames), ', '.join(defaultLabelNames)))
    # add option to show information on available entries ()
    optparser.add_option(
        '--list-functions',
        type="string",
        dest="list_functions", default=None,
        help="""\
list functions available for selection in -z or -l, requires selector argument
( use '+' to select all).
Recall that the selector argument is used with Unix/Bash globbing/pattern matching,
and that entries are formatted '<pkg>:<linenum>:<function>'. When argument starts
with '%', a dump of all available information is performed for selected entries,
 after removal of leading '%'.
""")
    # add option to create subtree or show paths
    optparser.add_option(
        '-z', '--root',
        type="string",
        dest="root", default="",
        help="prune call graph to show only descendants of specified root function")
    optparser.add_option(
        '-l', '--leaf',
        type="string",
        dest="leaf", default="",
        help="prune call graph to show only ancestors of specified leaf function")
    optparser.add_option(
        '--depth',
        type="int",
        dest="depth", default=-1,
        help="prune call graph to show only descendants or ancestors until specified depth")
    # add a new option to control skew of the colorization curve
    optparser.add_option(
        '--skew',
        type="float", dest="theme_skew", default=1.0,
        help="skew the colorization curve.  Values < 1.0 give more variety to lower percentages.  Values > 1.0 give less variety to lower percentages")
    # add option for filtering by file path
    optparser.add_option(
        '-p', '--path', action="append",
        type="string", dest="filter_paths",
        help="Filter all modules not in a specified path")
    optparser.add_option(
        '--compare',
        action="store_true",
        dest="compare", default=False,
        help="Compare two graphs with almost identical structure. With this option two files should be provided."
             "gprof2dot.py [options] --compare [file1] [file2] ...")
    optparser.add_option(
        '--compare-tolerance',
        type="float", dest="tolerance", default=0.001,
        help="Tolerance threshold for node difference (default=0.001%)."
             "If the difference is below this value the nodes are considered identical.")
    optparser.add_option(
        '--compare-only-slower',
        action="store_true",
        dest="only_slower", default=False,
        help="Display comparison only for function which are slower in second graph.")
    optparser.add_option(
        '--compare-only-faster',
        action="store_true",
        dest="only_faster", default=False,
        help="Display comparison only for function which are faster in second graph.")
    optparser.add_option(
        '--compare-color-by-difference',
        action="store_true",
        dest="color_by_difference", default=False,
        help="Color nodes based on the value of the difference. "
             "Nodes with the largest differences represent the hot spots.")
    (options, args) = optparser.parse_args(argv)

    if len(args) > 1 and options.format != 'pstats' and not options.compare:
        optparser.error('incorrect number of arguments')

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

    # set skew on the theme now that it has been picked.
    if options.theme_skew:
        theme.skew = options.theme_skew

    totalMethod = options.totalMethod
    timeFormat = options.time_format

    try:
        Format = formats[options.format]
    except KeyError:
        optparser.error('invalid format \'%s\'' % options.format)

    if Format.stdinInput:
        if not args:
            fp = sys.stdin
            parser = Format(fp)
        elif options.compare:
            fp1 = open(args[0], 'rt', encoding='UTF-8')
            fp2 = open(args[1], 'rt', encoding='UTF-8')
            parser1 = Format(fp1)
            parser2 = Format(fp2)
        else:
            fp = open(args[0], 'rb')
            bom = fp.read(2)
            if bom == codecs.BOM_UTF16_LE:
                # Default on Windows PowerShell (https://github.com/jrfonseca/gprof2dot/issues/88)
                encoding = 'utf-16le'
            else:
                encoding = 'utf-8'
            fp.seek(0)
            fp = io.TextIOWrapper(fp, encoding=encoding)
            parser = Format(fp)
    elif Format.multipleInput:
        if not args:
            optparser.error('at least a file must be specified for %s input' % options.format)
        if options.compare:
            parser1 = Format(args[-2])
            parser2 = Format(args[-1])
        else:
            parser = Format(*args)
    else:
        if len(args) != 1:
            optparser.error('exactly one file must be specified for %s input' % options.format)
        parser = Format(args[0])

    if options.compare:
        profile1 = parser1.parse()
        profile2 = parser2.parse()
    else:
        profile = parser.parse()

    if options.output is None:
        output = open(sys.stdout.fileno(), mode='wt', encoding='UTF-8', closefd=False)
    else:
        output = open(options.output, 'wt', encoding='UTF-8')

    dot = DotWriter(output)
    dot.strip = options.strip
    dot.wrap = options.wrap

    labelNames = options.node_labels or defaultLabelNames
    dot.show_function_events = [labels[l] for l in labelNames]
    if options.show_samples:
        dot.show_function_events.append(SAMPLES)

    if options.compare:
        profile1.prune(options.node_thres/100.0, options.edge_thres/100.0, options.filter_paths,
                       options.color_nodes_by_selftime)
        profile2.prune(options.node_thres/100.0, options.edge_thres/100.0, options.filter_paths,
                       options.color_nodes_by_selftime)

        if options.root:
            profile1.prune_root(profile1.getFunctionIds(options.root), options.depth)
            profile2.prune_root(profile2.getFunctionIds(options.root), options.depth)
    else:
        profile.prune(options.node_thres/100.0, options.edge_thres/100.0, options.filter_paths,
                      options.color_nodes_by_selftime)
        if options.root:
            rootIds = profile.getFunctionIds(options.root)
            if not rootIds:
                sys.stderr.write('root node ' + options.root + ' not found (might already be pruned : try -e0 -n0 flags)\n')
                sys.exit(1)
            profile.prune_root(rootIds, options.depth)

    if options.list_functions:
        profile.printFunctionIds(selector=options.list_functions)
        sys.exit(0)

    if options.leaf:
        leafIds = profile.getFunctionIds(options.leaf)
        if not leafIds:
            sys.stderr.write('leaf node ' + options.leaf + ' not found (maybe already pruned : try -e0 -n0 flags)\n')
            sys.exit(1)
        profile.prune_leaf(leafIds, options.depth)

    if options.compare:
        dot.graphs_compare(profile1, profile2, theme, options)
    else:
        dot.graph(profile, theme)


if __name__ == '__main__':
    main()