/brz/remove-bazaar

# Copyright (C) 2006, 2008, 2009, 2010 by Canonical Ltd

# Written by John Arbash Meinel <john@arbash-meinel.com>

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 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 General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

"""A custom importer and regex compiler which logs time spent."""

from __future__ import absolute_import

import re

import sys

import time

_parent_stack = []

_total_stack = {}

_info = {}

_cur_id = 0

_timer = time.time

if sys.platform == 'win32':

    _timer = time.clock

def stack_add(name, frame_name, frame_lineno, scope_name=None):

    """Start a new record on the stack"""

    global _cur_id

    _cur_id += 1

    this_stack = (_cur_id, name)

    if _parent_stack:

        _total_stack[_parent_stack[-1]].append(this_stack)

    _total_stack[this_stack] = []

    _parent_stack.append(this_stack)

    _info[this_stack] = [len(_parent_stack)-1, frame_name, frame_lineno, scope_name]

    return this_stack

def stack_finish(this, cost):

    """Finish a given entry, and record its cost in time"""

    global _parent_stack

    assert _parent_stack[-1] == this, \

        'import stack does not end with this %s: %s' % (this, _parent_stack)

    _parent_stack.pop()

    _info[this].append(cost)

def log_stack_info(out_file, sorted=True, hide_fast=True):

    # Find all of the roots with import = 0

    out_file.write('%5s %5s %-40s @ %s:%s\n'

        % ('cum', 'local', 'name', 'file', 'line'))

    todo = [(value[-1], key) for key,value in _info.items() if value[0] == 0]

    if sorted:

        todo.sort()

    while todo:

        cum_time, cur = todo.pop()

        children = _total_stack[cur]

        c_times = []

        info = _info[cur]

        if hide_fast and info[-1] < 0.0001:

            continue

        # Compute the module time by removing the children times

        mod_time = info[-1]

        for child in children:

            c_info = _info[child]

            mod_time -= c_info[-1]

            c_times.append((c_info[-1], child))

        # indent, cum_time, mod_time, name,

        # scope_name, frame_name, frame_lineno

        out_file.write('%5.1f %5.1f %-40s @ %s:%d\n'

            % (info[-1]*1000., mod_time*1000.,

               ('+'*info[0] + cur[1]),

               info[1], info[2]))

        if sorted:

            c_times.sort()

        else:

            c_times.reverse()

        todo.extend(c_times)

_real_import = __import__

def timed_import(name, globals=None, locals=None, fromlist=None, level=0):

    """Wrap around standard importer to log import time"""

    # normally there are 4, but if this is called as __import__ eg by

    # /usr/lib/python2.6/email/__init__.py then there may be only one

    # parameter

    # level has different default between Python 2 and 3, but codebase

    # uses `from __future__ import absolute_import` so can just use 0.

    if globals is None:

        # can't determine the scope name afaics; we could peek up the stack to

        # see where this is being called from, but it should be a rare case.

        scope_name = None

    else:

        scope_name = globals.get('__name__', None)

        if scope_name is None:

            scope_name = globals.get('__file__', None)

        if scope_name is None:

            scope_name = globals.keys()

        else:

            # Trim out paths before breezy

            loc = scope_name.find('breezy')

            if loc != -1:

                scope_name = scope_name[loc:]

    # Figure out the frame that is doing the importing

    frame = sys._getframe(1)

    frame_name = frame.f_globals.get('__name__', '<unknown>')

    extra = ''

    if frame_name.endswith('demandload'):

        # If this was demandloaded, we have 3 frames to ignore

        extra = '(demandload) '

        frame = sys._getframe(4)

        frame_name = frame.f_globals.get('__name__', '<unknown>')

    elif frame_name.endswith('lazy_import'):

        # If this was lazily imported, we have 3 frames to ignore

        extra = '[l] '

        frame = sys._getframe(4)

        frame_name = frame.f_globals.get('__name__', '<unknown>')

    if fromlist:

        extra += ' [%s]' % (', '.join(map(str, fromlist)),)

    frame_lineno = frame.f_lineno

    this = stack_add(extra + name, frame_name, frame_lineno, scope_name)

    tstart = _timer()

    try:

        # Do the import

        return _real_import(name, globals, locals, fromlist, level=level)

    finally:

        tload = _timer()-tstart

        stack_finish(this, tload)

def _repr_regexp(pattern, max_len=30):

    """Present regexp pattern for logging, truncating if over max_len."""

    if len(pattern) > max_len:

        return repr(pattern[:max_len-3]) + "..."

    return repr(pattern)

_real_compile = re._compile

def timed_compile(*args, **kwargs):

    """Log how long it takes to compile a regex"""

    # And who is requesting this?

    frame = sys._getframe(2)

    frame_name = frame.f_globals.get('__name__', '<unknown>')

    extra = ''

    if frame_name.endswith('lazy_regex'):

        # If this was lazily compiled, we have 3 more frames to ignore

        extra = '[l] '

        frame = sys._getframe(5)

        frame_name = frame.f_globals.get('__name__', '<unknown>')

    frame_lineno = frame.f_lineno

    this = stack_add(extra+_repr_regexp(args[0]), frame_name, frame_lineno)

    tstart = _timer()

    try:

        # Measure the compile time

        comp = _real_compile(*args, **kwargs)

    finally:

        tcompile = _timer() - tstart

        stack_finish(this, tcompile)

    return comp

def install():

    """Install the hooks for measuring import and regex compile time."""

    __builtins__['__import__'] = timed_import

    re._compile = timed_compile

def uninstall():

    """Remove the import and regex compile timing hooks."""

    __builtins__['__import__'] = _real_import

    re._compile = _real_compile