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path: root/urlgrabber/progress.py
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#   This library 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 2.1 of the License, or (at your option) any later version.
#
#   This library 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 library; if not, write to the 
#      Free Software Foundation, Inc., 
#      59 Temple Place, Suite 330, 
#      Boston, MA  02111-1307  USA

# This file is part of urlgrabber, a high-level cross-protocol url-grabber
# Copyright 2002-2004 Michael D. Stenner, Ryan Tomayko


import sys
import time
import math
import thread
import fcntl
import struct
import termios

# Code from http://mail.python.org/pipermail/python-list/2000-May/033365.html
def terminal_width(fd=1):
    """ Get the real terminal width """
    try:
        buf = 'abcdefgh'
        buf = fcntl.ioctl(fd, termios.TIOCGWINSZ, buf)
        ret = struct.unpack('hhhh', buf)[1]
        if ret == 0:
            return 80
        # Add minimum too?
        return ret
    except: # IOError
        return 80

_term_width_val  = None
_term_width_last = None
def terminal_width_cached(fd=1, cache_timeout=1.000):
    """ Get the real terminal width, but cache it for a bit. """
    global _term_width_val
    global _term_width_last

    now = time.time()
    if _term_width_val is None or (now - _term_width_last) > cache_timeout:
        _term_width_val  = terminal_width(fd)
        _term_width_last = now
    return _term_width_val

class TerminalLine:
    """ Help create dynamic progress bars, uses terminal_width_cached(). """

    def __init__(self, min_rest=0, beg_len=None, fd=1, cache_timeout=1.000):
        if beg_len is None:
            beg_len = min_rest
        self._min_len = min_rest
        self._llen    = terminal_width_cached(fd, cache_timeout)
        if self._llen < beg_len:
            self._llen = beg_len
        self._fin = False

    def __len__(self):
        """ Usable length for elements. """
        return self._llen - self._min_len

    def rest_split(self, fixed, elements=2):
        """ After a fixed length, split the rest of the line length among
            a number of different elements (default=2). """
        if self._llen < fixed:
            return 0
        return (self._llen - fixed) / elements

    def add(self, element, full_len=None):
        """ If there is room left in the line, above min_len, add element.
            Note that as soon as one add fails all the rest will fail too. """

        if full_len is None:
            full_len = len(element)
        if len(self) < full_len:
            self._fin = True
        if self._fin:
            return ''

        self._llen -= len(element)
        return element

    def rest(self):
        """ Current rest of line, same as .rest_split(fixed=0, elements=1). """
        return self._llen

class BaseMeter:
    def __init__(self):
        self.update_period = 0.3 # seconds

        self.filename   = None
        self.url        = None
        self.basename   = None
        self.text       = None
        self.size       = None
        self.start_time = None
        self.last_amount_read = 0
        self.last_update_time = None
        self.re = RateEstimator()
        
    def start(self, filename=None, url=None, basename=None,
              size=None, now=None, text=None):
        self.filename = filename
        self.url      = url
        self.basename = basename
        self.text     = text

        #size = None #########  TESTING
        self.size = size
        if not size is None: self.fsize = format_number(size) + 'B'

        if now is None: now = time.time()
        self.start_time = now
        self.re.start(size, now)
        self.last_amount_read = 0
        self.last_update_time = now
        self._do_start(now)
        
    def _do_start(self, now=None):
        pass

    def update(self, amount_read, now=None):
        # for a real gui, you probably want to override and put a call
        # to your mainloop iteration function here
        if now is None: now = time.time()
        if (not self.last_update_time or
            (now >= self.last_update_time + self.update_period)):
            self.re.update(amount_read, now)
            self.last_amount_read = amount_read
            self.last_update_time = now
            self._do_update(amount_read, now)

    def _do_update(self, amount_read, now=None):
        pass

    def end(self, amount_read, now=None):
        if now is None: now = time.time()
        self.re.update(amount_read, now)
        self.last_amount_read = amount_read
        self.last_update_time = now
        self._do_end(amount_read, now)

    def _do_end(self, amount_read, now=None):
        pass
        
#  This is kind of a hack, but progress is gotten from grabber which doesn't
# know about the total size to download. So we do this so we can get the data
# out of band here. This will be "fixed" one way or anther soon.
_text_meter_total_size = 0
_text_meter_sofar_size = 0
def text_meter_total_size(size, downloaded=0):
    global _text_meter_total_size
    global _text_meter_sofar_size
    _text_meter_total_size = size
    _text_meter_sofar_size = downloaded

#
#       update: No size (minimal: 17 chars)
#       -----------------------------------
# <text>                          <rate> | <current size> <elapsed time> 
#  8-48                          1    8  3             6 1            9 5
#
# Order: 1. <text>+<current size> (17)
#        2. +<elapsed time>       (10, total: 27)
#        3. +                     ( 5, total: 32)
#        4. +<rate>               ( 9, total: 41)
#
#       update: Size, Single file
#       -------------------------
# <text>            <pc>  <bar> <rate> | <current size> <eta time> ETA
#  8-25            1 3-4 1 6-16 1   8  3             6 1        9 1  3 1
#
# Order: 1. <text>+<current size> (17)
#        2. +<eta time>           (10, total: 27)
#        3. +ETA                  ( 5, total: 32)
#        4. +<pc>                 ( 4, total: 36)
#        5. +<rate>               ( 9, total: 45)
#        6. +<bar>                ( 7, total: 52)
#
#       update: Size, All files
#       -----------------------
# <text> <total pc> <pc>  <bar> <rate> | <current size> <eta time> ETA
#  8-22 1      5-7 1 3-4 1 6-12 1   8  3             6 1        9 1  3 1
#
# Order: 1. <text>+<current size> (17)
#        2. +<eta time>           (10, total: 27)
#        3. +ETA                  ( 5, total: 32)
#        4. +<total pc>           ( 5, total: 37)
#        4. +<pc>                 ( 4, total: 41)
#        5. +<rate>               ( 9, total: 50)
#        6. +<bar>                ( 7, total: 57)
#
#       end
#       ---
# <text>                                 | <current size> <elapsed time> 
#  8-56                                  3             6 1            9 5
#
# Order: 1. <text>                ( 8)
#        2. +<current size>       ( 9, total: 17)
#        3. +<elapsed time>       (10, total: 27)
#        4. +                     ( 5, total: 32)
#

def _term_add_bar(tl, bar_max_length, pc):
    blen = bar_max_length
    bar  = '='*int(blen * pc)
    if (blen * pc) - int(blen * pc) >= 0.5:
        bar += '-'
    return tl.add(' [%-*.*s]' % (blen, blen, bar))

def _term_add_end(tl, osize, size):
    if osize: # osize should be None or >0, but that's been broken.
        if size > osize: # Is ??? better? Really need something to say < vs >.
            return tl.add(' !!! '), True
        elif size != osize:
            return tl.add(' ... '), True
    return tl.add(' ' * 5), False

class TextMeter(BaseMeter):
    def __init__(self, fo=sys.stderr):
        BaseMeter.__init__(self)
        self.fo = fo

    def _do_update(self, amount_read, now=None):
        etime = self.re.elapsed_time()
        fread = format_number(amount_read)
        #self.size = None
        if self.text is not None:
            text = self.text
        else:
            text = self.basename

        ave_dl = format_number(self.re.average_rate())
        sofar_size = None
        if _text_meter_total_size:
            sofar_size = _text_meter_sofar_size + amount_read
            sofar_pc   = (sofar_size * 100) / _text_meter_total_size

        # Include text + ui_rate in minimal
        tl = TerminalLine(8, 8+1+8)
        if tl._llen > 80:
            use_hours = True # For big screens, make it more readable.
        else:
            use_hours = False
        ui_size = tl.add(' | %5sB' % fread)
        if self.size is None:
            ui_time = tl.add('  %s' % format_time(etime, use_hours))
            ui_end  = tl.add(' ' * 5)
            ui_rate = tl.add(' %5sB/s' % ave_dl)
            out = '%-*.*s%s%s%s%s\r' % (tl.rest(), tl.rest(), text,
                                        ui_rate, ui_size, ui_time, ui_end)
        else:
            rtime = self.re.remaining_time()
            frtime = format_time(rtime, use_hours)
            frac = self.re.fraction_read()

            ui_time = tl.add('  %s' % frtime)
            ui_end  = tl.add(' ETA ')

            if sofar_size is None:
                ui_sofar_pc = ''
            else:
                ui_sofar_pc = tl.add(' (%i%%)' % sofar_pc,
                                     full_len=len(" (100%)"))

            ui_pc   = tl.add(' %2i%%' % (frac*100))
            ui_rate = tl.add(' %5sB/s' % ave_dl)
            # Make text grow a bit before we start growing the bar too
            blen = 4 + tl.rest_split(8 + 8 + 4)
            ui_bar = _term_add_bar(tl, blen, frac)
            out = '\r%-*.*s%s%s%s%s%s%s%s\r' % (tl.rest(), tl.rest(), text,
                                                ui_sofar_pc, ui_pc, ui_bar,
                                                ui_rate,ui_size,ui_time, ui_end)

        self.fo.write(out)
        self.fo.flush()

    def _do_end(self, amount_read, now=None):
        global _text_meter_total_size
        global _text_meter_sofar_size

        total_size = format_number(amount_read)
        if self.text is not None:
            text = self.text
        else:
            text = self.basename

        tl = TerminalLine(8)
        if tl._llen > 80:
            use_hours = True # For big screens, make it more readable.
        else:
            use_hours = False
        ui_size = tl.add(' | %5sB' % total_size)
        ui_time = tl.add('  %s' % format_time(self.re.elapsed_time(), use_hours))
        ui_end, not_done = _term_add_end(tl, self.size, amount_read)
        out = '\r%-*.*s%s%s%s\n' % (tl.rest(), tl.rest(), text,
                                    ui_size, ui_time, ui_end)
        self.fo.write(out)
        self.fo.flush()

        # Don't add size to the sofar size until we have all of it.
        # If we don't have a size, then just pretend/hope we got all of it.
        if not_done:
            return

        if _text_meter_total_size:
            _text_meter_sofar_size += amount_read
        if _text_meter_total_size <= _text_meter_sofar_size:
            _text_meter_total_size = 0
            _text_meter_sofar_size = 0

text_progress_meter = TextMeter

class MultiFileHelper(BaseMeter):
    def __init__(self, master):
        BaseMeter.__init__(self)
        self.master = master

    def _do_start(self, now):
        self.master.start_meter(self, now)

    def _do_update(self, amount_read, now):
        # elapsed time since last update
        self.master.update_meter(self, now)

    def _do_end(self, amount_read, now):
        self.ftotal_time = format_time(now - self.start_time)
        self.ftotal_size = format_number(self.last_amount_read)
        self.master.end_meter(self, now)

    def failure(self, message, now=None):
        self.master.failure_meter(self, message, now)

    def message(self, message):
        self.master.message_meter(self, message)

class _FakeLock:
    def acquire(self):
        pass
    def release(self):
        pass

class MultiFileMeter:
    helperclass = MultiFileHelper
    def __init__(self, threaded=True):
        self.meters = []
        self.in_progress_meters = []
        if threaded:
            self._lock = thread.allocate_lock()
        else:
            self._lock = _FakeLock()
        self.update_period = 0.3 # seconds
        
        self.numfiles         = None
        self.finished_files   = 0
        self.failed_files     = 0
        self.open_files       = 0
        self.total_size       = None
        self.failed_size      = 0
        self.start_time       = None
        self.finished_file_size = 0
        self.last_update_time = None
        self.re = RateEstimator()

    def start(self, numfiles=None, total_size=None, now=None):
        if now is None: now = time.time()
        self.numfiles         = numfiles
        self.finished_files   = 0
        self.failed_files     = 0
        self.open_files       = 0
        self.total_size       = total_size
        self.failed_size      = 0
        self.start_time       = now
        self.finished_file_size = 0
        self.last_update_time = now
        self.re.start(total_size, now)
        self._do_start(now)

    def _do_start(self, now):
        pass

    def end(self, now=None):
        if now is None: now = time.time()
        self.re.update(self._amount_read(), now)
        self._do_end(now)
        
    def _do_end(self, now):
        pass

    def lock(self): self._lock.acquire()
    def unlock(self): self._lock.release()

    ###########################################################
    # child meter creation and destruction
    def newMeter(self):
        newmeter = self.helperclass(self)
        self.meters.append(newmeter)
        return newmeter
    
    def removeMeter(self, meter):
        self.meters.remove(meter)
        
    ###########################################################
    # child functions - these should only be called by helpers
    def start_meter(self, meter, now):
        if not meter in self.meters:
            raise ValueError('attempt to use orphaned meter')
        self._lock.acquire()
        try:
            if not meter in self.in_progress_meters:
                self.in_progress_meters.append(meter)
                self.open_files += 1
        finally:
            self._lock.release()
        self._do_start_meter(meter, now)
        
    def _do_start_meter(self, meter, now):
        pass
        
    def update_meter(self, meter, now):
        if not meter in self.meters:
            raise ValueError('attempt to use orphaned meter')
        if (not self.last_update_time or
            (now >= self.last_update_time + self.update_period)):
            self.re.update(self._amount_read(), now)
            self.last_update_time = now
            self._do_update_meter(meter, now)

    def _do_update_meter(self, meter, now):
        pass

    def end_meter(self, meter, now):
        if not meter in self.meters:
            raise ValueError('attempt to use orphaned meter')
        self._lock.acquire()
        try:
            try: self.in_progress_meters.remove(meter)
            except ValueError: pass
            self.open_files     -= 1
            self.finished_files += 1
            self.finished_file_size += meter.last_amount_read
        finally:
            self._lock.release()
        self._do_end_meter(meter, now)

    def _do_end_meter(self, meter, now):
        pass

    def failure_meter(self, meter, message, now):
        if not meter in self.meters:
            raise ValueError('attempt to use orphaned meter')
        self._lock.acquire()
        try:
            try: self.in_progress_meters.remove(meter)
            except ValueError: pass
            self.open_files     -= 1
            self.failed_files   += 1
            if meter.size and self.failed_size is not None:
                self.failed_size += meter.size
            else:
                self.failed_size = None
        finally:
            self._lock.release()
        self._do_failure_meter(meter, message, now)

    def _do_failure_meter(self, meter, message, now):
        pass

    def message_meter(self, meter, message):
        pass

    ########################################################
    # internal functions
    def _amount_read(self):
        tot = self.finished_file_size
        for m in self.in_progress_meters:
            tot += m.last_amount_read
        return tot


class TextMultiFileMeter(MultiFileMeter):
    def __init__(self, fo=sys.stderr, threaded=True):
        self.fo = fo
        MultiFileMeter.__init__(self, threaded)
        self.index_time = self.index = 0

    # files: ###/### ###%  data: ######/###### ###%  time: ##:##:##/##:##:##
# New output, like TextMeter output...
#       update: No size (minimal: 17 chars)
#       -----------------------------------
# (<#file>/<#tot files>): <text>            <rate> | <current size> <elapsed>
#                          8-48            1    8  3             6 1      7-9 5
#
#       update: Size, All files
#       -----------------------
# (<#file>/<#tot files>): <text> <pc> <bar> <rate> | <size> <eta time> ETA
#                          8-22 1 3-4 1 6-12 1   8 3     6 1       7-9 1  3 1
#       end
#       ---
# <text>                                 | <file size> <file elapsed time> 
#  8-56                                  3          6 1                 9 5
    def _do_update_meter(self, meter, now):
        self._lock.acquire()
        try:
            df = self.finished_files
            tf = self.numfiles or 1
            # Don't use "percent of files complete" ...
            # pf = 100 * float(df)/tf + 0.49
            dd = self.re.last_amount_read
            td = self.re.total
            pd = 100 * (self.re.fraction_read() or 0) + 0.49
            dt = self.re.elapsed_time()
            rt = self.re.remaining_time()

            frac = self.re.fraction_read() or 0
            pf   = 100 * frac
            ave_dl = format_number(self.re.average_rate())

            # cycle through active meters
            if now > self.index_time:
                self.index_time = now + 1.0
                self.index += 1
            if self.index >= len(self.meters):
                self.index = 0
            meter = self.meters[self.index]
            text = meter.text or meter.basename
            if tf > 1:
                text = '(%u/%u): %s' % (df+1+self.index, tf, text)

            # Include text + ui_rate in minimal
            tl = TerminalLine(8, 8+1+8)
            if tl._llen > 80:
                use_hours = True # For big screens, make it more readable.
            else:
                use_hours = False
            ui_size = tl.add(' | %5sB' % format_number(dd))
            if not self.re.total:
                ui_time = tl.add('  %s' % format_time(dt, use_hours))
                ui_end  = tl.add(' ' * 5)
                ui_rate = tl.add(' %5sB/s' % ave_dl)
                out = '\r%-*.*s%s%s%s%s\r' % (tl.rest(), tl.rest(), text,
                                              ui_rate, ui_size, ui_time, ui_end)
            else:
                ui_time = tl.add('  %s' % format_time(rt, use_hours))
                ui_end  = tl.add(' ETA ')

                ui_sofar_pc = tl.add(' %i%%' % pf,
                                     full_len=len(" (100%)"))
                ui_rate = tl.add(' %5sB/s' % ave_dl)

                # Make text grow a bit before we start growing the bar too
                blen = 4 + tl.rest_split(8 + 8 + 4)
                ui_bar = _term_add_bar(tl, blen, frac)
                out = '\r%-*.*s%s%s%s%s%s%s\r' % (tl.rest(), tl.rest(), text,
                                                  ui_sofar_pc, ui_bar,
                                                  ui_rate, ui_size, ui_time,
                                                  ui_end)
            self.fo.write(out)
            self.fo.flush()
        finally:
            self._lock.release()

    def _do_end_meter(self, meter, now):
        self._lock.acquire()
        try:
            format = "%-30.30s %6.6s    %8.8s    %9.9s"
            fn = meter.text or meter.basename
            size = meter.last_amount_read
            fsize = format_number(size) + 'B'
            et = meter.re.elapsed_time()
            frate = format_number(et and size / et) + 'B/s'
            df = self.finished_files
            tf = self.numfiles or 1

            total_size = format_number(size)
            text = meter.text or meter.basename
            if tf > 1:
                text = '(%u/%u): %s' % (df, tf, text)

            tl = TerminalLine(8)
            if tl._llen > 80:
                use_hours = True # For big screens, make it more readable.
            else:
                use_hours = False
            ui_size = tl.add(' | %5sB' % total_size)
            ui_time = tl.add('  %s' % format_time(et, use_hours))
            ui_end, not_done = _term_add_end(tl, meter.size, size)
            out = '\r%-*.*s%s%s%s\n' % (tl.rest(), tl.rest(), text,
                                        ui_size, ui_time, ui_end)
            self.fo.write(out)
        finally:
            self._lock.release()

    def _do_failure_meter(self, meter, message, now):
        self._lock.acquire()
        try:
            format = "%-30.30s %6.6s %s"
            fn = meter.text or meter.basename
            if type(message) in (type(''), type(u'')):
                message = message.splitlines()
            if not message: message = ['']
            out = '%-79s' % (format % (fn, 'FAILED', message[0] or ''))
            self.fo.write('\r' + out + '\n')
            for m in message[1:]: self.fo.write('  ' + m + '\n')
            self._lock.release()
        finally:
            self._do_update_meter(meter, now)

    def message_meter(self, meter, message):
        self._lock.acquire()
        try:
            pass
        finally:
            self._lock.release()
        
######################################################################
# support classes and functions

class RateEstimator:
    def __init__(self, timescale=5.0):
        self.timescale = timescale

    def start(self, total=None, now=None):
        if now is None: now = time.time()
        self.total = total
        self.start_time = now
        self.last_update_time = now
        self.last_amount_read = 0
        self.ave_rate = None
        
    def update(self, amount_read, now=None):
        if now is None: now = time.time()
        # libcurl calls the progress callback when fetching headers
        # too, thus amount_read = 0 .. hdr_size .. 0 .. content_size.
        # Ocassionally we miss the 2nd zero and report avg speed < 0.
        # Handle read_diff < 0 here. BZ 1001767.
        if amount_read == 0 or amount_read < self.last_amount_read:
            # if we just started this file, all bets are off
            self.last_update_time = now
            self.last_amount_read = amount_read
            self.ave_rate = None
            return

        #print 'times', now, self.last_update_time
        time_diff = now         - self.last_update_time
        read_diff = amount_read - self.last_amount_read
        # First update, on reget is the file size
        if self.last_amount_read:
            self.last_update_time = now
            self.ave_rate = self._temporal_rolling_ave(\
                time_diff, read_diff, self.ave_rate, self.timescale)
        self.last_amount_read = amount_read
        #print 'results', time_diff, read_diff, self.ave_rate
        
    #####################################################################
    # result methods
    def average_rate(self):
        "get the average transfer rate (in bytes/second)"
        return self.ave_rate

    def elapsed_time(self):
        "the time between the start of the transfer and the most recent update"
        return self.last_update_time - self.start_time

    def remaining_time(self):
        "estimated time remaining"
        if not self.ave_rate or not self.total: return None
        return (self.total - self.last_amount_read) / self.ave_rate

    def fraction_read(self):
        """the fraction of the data that has been read
        (can be None for unknown transfer size)"""
        if self.total is None: return None
        elif self.total == 0: return 1.0
        else: return float(self.last_amount_read)/self.total

    #########################################################################
    # support methods
    def _temporal_rolling_ave(self, time_diff, read_diff, last_ave, timescale):
        """a temporal rolling average performs smooth averaging even when
        updates come at irregular intervals.  This is performed by scaling
        the "epsilon" according to the time since the last update.
        Specifically, epsilon = time_diff / timescale

        As a general rule, the average will take on a completely new value
        after 'timescale' seconds."""
        epsilon = time_diff / timescale
        if epsilon > 1: epsilon = 1.0
        return self._rolling_ave(time_diff, read_diff, last_ave, epsilon)
    
    def _rolling_ave(self, time_diff, read_diff, last_ave, epsilon):
        """perform a "rolling average" iteration
        a rolling average "folds" new data into an existing average with
        some weight, epsilon.  epsilon must be between 0.0 and 1.0 (inclusive)
        a value of 0.0 means only the old value (initial value) counts,
        and a value of 1.0 means only the newest value is considered."""
        
        try:
            recent_rate = read_diff / time_diff
        except ZeroDivisionError:
            recent_rate = None
        if last_ave is None: return recent_rate
        elif recent_rate is None: return last_ave

        # at this point, both last_ave and recent_rate are numbers
        return epsilon * recent_rate  +  (1 - epsilon) * last_ave

    def _round_remaining_time(self, rt, start_time=15.0):
        """round the remaining time, depending on its size
        If rt is between n*start_time and (n+1)*start_time round downward
        to the nearest multiple of n (for any counting number n).
        If rt < start_time, round down to the nearest 1.
        For example (for start_time = 15.0):
         2.7  -> 2.0
         25.2 -> 25.0
         26.4 -> 26.0
         35.3 -> 34.0
         63.6 -> 60.0
        """

        if rt < 0: return 0.0
        shift = int(math.log(rt/start_time)/math.log(2))
        rt = int(rt)
        if shift <= 0: return rt
        return float(int(rt) >> shift << shift)
        

def format_time(seconds, use_hours=0):
    if seconds is None or seconds < 0:
        if use_hours: return '--:--:--'
        else:         return '--:--'
    elif seconds == float('inf'):
        return 'Infinite'
    else:
        seconds = int(seconds)
        minutes = seconds / 60
        seconds = seconds % 60
        if use_hours:
            hours = minutes / 60
            minutes = minutes % 60
            return '%02i:%02i:%02i' % (hours, minutes, seconds)
        else:
            return '%02i:%02i' % (minutes, seconds)
            
def format_number(number, SI=0, space=' '):
    """Turn numbers into human-readable metric-like numbers"""
    symbols = ['',  # (none)
               'k', # kilo
               'M', # mega
               'G', # giga
               'T', # tera
               'P', # peta
               'E', # exa
               'Z', # zetta
               'Y'] # yotta
    
    if SI: step = 1000.0
    else: step = 1024.0

    thresh = 999
    depth = 0
    max_depth = len(symbols) - 1
    
    # we want numbers between 0 and thresh, but don't exceed the length
    # of our list.  In that event, the formatting will be screwed up,
    # but it'll still show the right number.
    while number > thresh and depth < max_depth:
        depth  = depth + 1
        number = number / step

    if type(number) == type(1) or type(number) == type(1L):
        # it's an int or a long, which means it didn't get divided,
        # which means it's already short enough
        format = '%i%s%s'
    elif number < 9.95:
        # must use 9.95 for proper sizing.  For example, 9.99 will be
        # rounded to 10.0 with the .1f format string (which is too long)
        format = '%.1f%s%s'
    else:
        format = '%.0f%s%s'
        
    return(format % (float(number or 0), space, symbols[depth]))

def _tst(fn, cur, tot, beg, size, *args):
    tm = TextMeter()
    text = "(%d/%d): %s" % (cur, tot, fn)
    tm.start(fn, "http://www.example.com/path/to/fn/" + fn, fn, size, text=text)
    num = beg
    off = 0
    for (inc, delay) in args:
        off += 1
        while num < ((size * off) / len(args)):
            num += inc
            tm.update(num)
            time.sleep(delay)
    tm.end(size)

def _mtst(datas, *args):
    print '-' * 79
    tm = TextMultiFileMeter(threaded=False)

    dl_sizes = {}

    num = 0
    total_size = 0
    dl_total_size = 0
    for data in datas:
        dl_size = None
        if len(data) == 2:
            fn, size = data
            dl_size = size
        if len(data) == 3:
            fn, size, dl_size = data
        nm = tm.newMeter()
        nm.start(fn, "http://www.example.com/path/to/fn/" + fn, fn, size,
                 text=fn)
        num += 1
        assert dl_size is not None
        dl_total_size += dl_size
        dl_sizes[nm] = dl_size
        if size is None or total_size is None:
            total_size = None
        else:
            total_size += size
    tm.start(num, total_size)

    num = 0
    off = 0
    for (inc, delay) in args:
        off += 1
        while num < ((dl_total_size * off) / len(args)):
            num += inc
            for nm in tm.meters[:]:
                if dl_sizes[nm] <= num:
                    nm.end(dl_sizes[nm])
                    tm.removeMeter(nm)
                else:
                    nm.update(num)
            time.sleep(delay)
    assert not tm.meters

if __name__ == "__main__":
    # (1/2): subversion-1.4.4-7.x86_64.rpm               2.4 MB /  85 kB/s    00:28     
    # (2/2): mercurial-0.9.5-6.fc8.x86_64.rpm            924 kB / 106 kB/s    00:08     
    if len(sys.argv) >= 2 and sys.argv[1] == 'multi':
        _mtst((("sm-1.0.0-1.fc8.i386.rpm", 1000),
               ("s-1.0.1-1.fc8.i386.rpm",  5000),
               ("m-1.0.1-2.fc8.i386.rpm", 10000)),
              (100, 0.33), (500, 0.25), (1000, 0.1))

        _mtst((("sm-1.0.0-1.fc8.i386.rpm", 1000),
               ("s-1.0.1-1.fc8.i386.rpm",  5000),
               ("m-1.0.1-2.fc8.i386.rpm",  None,  10000)),
              (100, 0.33), (500, 0.25), (1000, 0.1))

        _mtst((("sm-1.0.0-1.fc8.i386.rpm", 1000),
               ("s-1.0.1-1.fc8.i386.rpm", 2500000),
               ("m-1.0.1-2.fc8.i386.rpm", 10000)),
              (10, 0.2), (50, 0.1), (1000, 0.1))

        _mtst((("sm-1.0.0-1.fc8.i386.rpm", 1000),
               ("s-1.0.1-1.fc8.i386.rpm",  None, 2500000),
               ("m-1.0.1-2.fc8.i386.rpm",  None, 10000)),
              (10, 0.2), (50, 0.1), (1000, 0.1))
        # (10, 0.2), (100, 0.1), (100, 0.1), (100, 0.25))
        # (10, 0.2), (100, 0.1), (100, 0.1), (100, 0.25))
        sys.exit(0)

    if len(sys.argv) >= 2 and sys.argv[1] == 'total':
        text_meter_total_size(1000 + 10000 + 10000 + 1000000 + 1000000 +
                              1000000 + 10000 + 10000 + 10000 + 1000000)
    _tst("sm-1.0.0-1.fc8.i386.rpm", 1, 10, 0, 1000,
         (10, 0.2), (10, 0.1), (100, 0.25))
    _tst("s-1.0.1-1.fc8.i386.rpm", 2, 10, 0, 10000,
         (10, 0.2), (100, 0.1), (100, 0.1), (100, 0.25))
    _tst("m-1.0.1-2.fc8.i386.rpm", 3, 10, 5000, 10000,
         (10, 0.2), (100, 0.1), (100, 0.1), (100, 0.25))
    _tst("large-file-name-Foo-11.8.7-4.5.6.1.fc8.x86_64.rpm", 4, 10, 0, 1000000,
         (1000, 0.2), (1000, 0.1), (10000, 0.1))
    _tst("large-file-name-Foo2-11.8.7-4.5.6.2.fc8.x86_64.rpm", 5, 10,
         500001, 1000000, (1000, 0.2), (1000, 0.1), (10000, 0.1))
    _tst("large-file-name-Foo3-11.8.7-4.5.6.3.fc8.x86_64.rpm", 6, 10,
         750002, 1000000, (1000, 0.2), (1000, 0.1), (10000, 0.1))
    _tst("large-file-name-Foo4-10.8.7-4.5.6.1.fc8.x86_64.rpm", 7, 10, 0, 10000,
         (100, 0.1))
    _tst("large-file-name-Foo5-10.8.7-4.5.6.2.fc8.x86_64.rpm", 8, 10,
         5001, 10000, (100, 0.1))
    _tst("large-file-name-Foo6-10.8.7-4.5.6.3.fc8.x86_64.rpm", 9, 10,
         7502, 10000, (1, 0.1))
    _tst("large-file-name-Foox-9.8.7-4.5.6.1.fc8.x86_64.rpm",  10, 10,
         0, 1000000, (10, 0.5),
         (100000, 0.1), (10000, 0.1), (10000, 0.1), (10000, 0.1),
         (100000, 0.1), (10000, 0.1), (10000, 0.1), (10000, 0.1),
         (100000, 0.1), (10000, 0.1), (10000, 0.1), (10000, 0.1),
         (100000, 0.1), (10000, 0.1), (10000, 0.1), (10000, 0.1),
         (100000, 0.1), (1, 0.1))