torrentqueue.py

BitTorrent（简称BT

# The contents of this file are subject to the BitTorrent Open Source License
# Version 1.0 (the License).  You may not copy or use this file, in either
# source code or executable form, except in compliance with the License.  You
# may obtain a copy of the License at http://www.bittorrent.com/license/.
#
# Software distributed under the License is distributed on an AS IS basis,
# WITHOUT WARRANTY OF ANY KIND, either express or implied.  See the License
# for the specific language governing rights and limitations under the
# License.

# Written by Uoti Urpala

from __future__ import division

import os
import sys
import threading

from BitTorrent.platform import bttime
from BitTorrent.download import Feedback, Multitorrent
from BitTorrent.controlsocket import ControlSocket
from BitTorrent.bencode import bdecode
from BitTorrent.ConvertedMetainfo import ConvertedMetainfo
from BitTorrent import BTFailure, BTShutdown, INFO, WARNING, ERROR, CRITICAL
from BitTorrent import configfile
from BitTorrent import FAQ_URL
import BitTorrent

# check if dns library from http://www.dnspython.org/ is either installed
# or the dns subdirectory has been copied to BitTorrent/dns
HAVE_DNS = False
try:
    from BitTorrent import dns
    sys.modules['dns'] = dns
    import dns.resolver
    HAVE_DNS = True
except:
    try:
        import dns.resolver
        HAVE_DNS = True
    except:
        pass

RUNNING = 0
RUN_QUEUED = 1
QUEUED = 2
KNOWN = 3
ASKING_LOCATION = 4


class TorrentInfo(object):

    def __init__(self):
        self.metainfo = None
        self.dlpath = None
        self.dl = None
        self.state = None
        self.completion = None
        self.finishtime = None
        self.uptotal = 0
        self.uptotal_old = 0
        self.downtotal = 0
        self.downtotal_old = 0


def decode_position(l, pred, succ, default=None):
    if default is None:
        default = len(l)
    if pred is None and succ is None:
        return default
    if pred is None:
        return 0
    if succ is None:
        return len(l)
    try:
        if l[0] == succ and pred not in l:
            return 0
        if l[-1] == pred and succ not in l:
            return len(l)
        i = l.index(pred)
        if l[i+1] == succ:
            return i+1
    except (ValueError, IndexError):
        pass
    return default


class TorrentQueue(Feedback):

    def __init__(self, config, ui_options, controlsocket):
        self.config = dict(config)
        self.ui_options = ui_options
        self.controlsocket = controlsocket
        self.config['def_running_torrents'] = 1 # !@# XXX
        self.config['max_running_torrents'] = 3 # !@# XXX
        self.doneflag = threading.Event()
        self.torrents = {}
        self.starting_torrent = None
        self.running_torrents = []
        self.queue = []
        self.other_torrents = []
        self.last_save_time = 0
        self.last_version_check = 0

    def run(self, ui, ui_wrap, startflag):
        self.ui = ui
        self.run_ui_task = ui_wrap
        self.multitorrent = Multitorrent(self.config, self.doneflag,
                                        self.global_error, listen_fail_ok=True)
        self.rawserver = self.multitorrent.rawserver
        self.controlsocket.set_rawserver(self.rawserver)
        self.controlsocket.start_listening(self.external_command)
        try:
            self._restore_state()
        except BTFailure, e:
            self.queue = []
            self.other_torrents = []
            self.torrents = {}
            self.global_error(ERROR, "Could not load saved state: "+str(e))
        else:
            for infohash in self.running_torrents + self.queue + \
                    self.other_torrents:
                t = self.torrents[infohash]
                if t.dlpath is not None:
                    t.completion = self.multitorrent.get_completion(
                        self.config, t.metainfo, t.dlpath)
                state = t.state
                if state == RUN_QUEUED:
                    state = RUNNING
                self.run_ui_task(self.ui.new_displayed_torrent, infohash,
                                 t.metainfo, t.dlpath, state, t.completion,
                                 t.uptotal, t.downtotal)
        self._check_queue()
        startflag.set()
        self._queue_loop()
        self._check_version()
        self.multitorrent.rawserver.listen_forever()
        self.multitorrent.close_listening_socket()
        self.controlsocket.close_socket()
        for infohash in list(self.running_torrents):
            t = self.torrents[infohash]
            if t.state == RUN_QUEUED:
                continue
            t.dl.shutdown()
            if t.dl is not None:  # possibly set to none by failed()
                totals = t.dl.get_total_transfer()
                t.uptotal = t.uptotal_old + totals[0]
                t.downtotal = t.downtotal_old + totals[1]
        self._dump_state()

    def _check_version(self):
        now = bttime()
        if self.last_version_check > now - 24*3600:
            return
        self.last_version_check = now
        if not HAVE_DNS:
            self.global_error(WARNING, "Version check failed: no DNS library")
            return
        threading.Thread(target=self._version_thread).start()

    def _version_thread(self):
        def error(level, text):
            def f():
                self.global_error(level, text)
            self.rawserver.external_add_task(f, 0)
        def splitversion(text):
            return [int(t) for t in text.split('.')]
        try:
            try:
                a = dns.resolver.query('version.bittorrent.com', 'TXT')
            except:
                # the exceptions from the library have empty str(),
                # just different classes...
                raise BTFailure('DNS query failed')
            if len(a) != 1:
                raise BTFailure('number of received TXT fields is not 1')
            value = iter(a).next() # the object doesn't support a[0]
            if len(value.strings) != 1:
                raise BTFailure('number of strings in reply is not 1?')
            s = value.strings[0].split(None, 2)
            myversion = splitversion(BitTorrent.version)
            if myversion[1] % 2 and len(s) > 1:
                s = s[1]
            else:
                s = s[0]
            try:
                latest = splitversion(s)
            except ValueError:
                raise BTFailure("Could not parse new version string")
            for my, new in zip(myversion, latest):
                if my > new:
                    break
                if my < new:
                    download_url = 'http://bittorrent.com/download.html'
                    if hasattr(self.ui, 'new_version'):
                        self.run_ui_task(self.ui.new_version, s,
                                         download_url)
                    else:
                        error(ERROR, "A newer version of BitTorrent is "
                              "available.\nYou can always get the latest "
                              "version from\n%s." % download_url)
        except Exception, e:
            error(WARNING, "Version check failed: " + str(e))

    def _dump_config(self):
        configfile.save_ui_config(self.config, 'btdownloadgui',
                               self.ui_options, self.global_error)

    def _dump_state(self):
        self.last_save_time = bttime()
        r = []
        def write_entry(infohash, t):
            if t.dlpath is None:
                assert t.state == ASKING_LOCATION
                r.append(infohash.encode('hex') + '\n')
            else:
                r.append(infohash.encode('hex') + ' ' + str(t.uptotal) + ' ' +
                    str(t.downtotal)+' '+t.dlpath.encode('string_escape')+'\n')
        r.append('BitTorrent UI state file, version 3\n')
        r.append('Running torrents\n')
        for infohash in self.running_torrents:
            write_entry(infohash, self.torrents[infohash])
        r.append('Queued torrents\n')
        for infohash in self.queue:
            write_entry(infohash, self.torrents[infohash])
        r.append('Known torrents\n')
        for infohash in self.other_torrents:
            write_entry(infohash, self.torrents[infohash])
        r.append('End\n')
        f = None
        try:
            f = file(os.path.join(self.config['data_dir'], 'ui_state'), 'wb')
            f.write(''.join(r))
            f.close()
        except Exception, e:
            self.global_error(ERROR, 'Could not save UI state: ' + str(e))
            if f is not None:
                f.close()

    def _restore_state(self):
        def decode_line(line):
            hashtext = line[:40]
            try:
                infohash = hashtext.decode('hex')
            except:
                raise BTFailure("Invalid state file contents")
            if len(infohash) != 20:
                raise BTFailure("Invalid state file contents")
            try:
                path = os.path.join(self.config['data_dir'], 'metainfo',
                                    hashtext)
                f = file(path, 'rb')
                data = f.read()
                f.close()
            except Exception, e:
                try:
                    f.close()
                except:
                    pass
                self.global_error(ERROR,"Error reading file "+path+" ("+str(e)+
                                  "), cannot restore state completely")
                return None
            if infohash in self.torrents:
                raise BTFailure("Invalid state file (duplicate entry)")
            t = TorrentInfo()
            self.torrents[infohash] = t
            try:
                t.metainfo = ConvertedMetainfo(bdecode(data))
            except Exception, e:
                self.global_error(ERROR, "Corrupt data in "+path+
                                  " , cannot restore torrent ("+str(e)+")")
                return None
            t.metainfo.reported_errors = True # suppress redisplay on restart
            if infohash != t.metainfo.infohash:
                self.global_error(ERROR, "Corrupt data in "+path+
                                  " , cannot restore torrent ("+str(e)+")")
                return None
            if len(line) == 41:
                t.dlpath = None
                return infohash, t
            try:
                if version < 2:
                    t.dlpath = line[41:-1].decode('string_escape')
                else:
                    up, down, dlpath = line[41:-1].split(' ', 2)
                    t.uptotal = t.uptotal_old = int(up)
                    t.downtotal = t.downtotal_old = int(down)
                    t.dlpath = dlpath.decode('string_escape')
            except ValueError:  # unpack, int(), decode()
                raise BTFailure('Invalid state file (bad entry)')
            return infohash, t
        filename = os.path.join(self.config['data_dir'], 'ui_state')
        if not os.path.exists(filename):
            return
        f = None
        try:
            f = file(filename, 'rb')
            lines = f.readlines()
            f.close()
        except Exception, e:
            if f is not None:
                f.close()
            raise BTFailure(str(e))
        i = iter(lines)
        try:
            txt = 'BitTorrent UI state file, version '
            version = i.next()
            if not version.startswith(txt):
                raise BTFailure('Bad UI state file')
            try:
                version = int(version[len(txt):-1])
            except:
                raise BTFailure('Bad UI state file version')
            if version > 3:
                raise BTFailure('Unsupported UI state file version (from '
                                'newer client version?')
            if version < 3:
                if i.next() != "Running/queued torrents\n":
                    raise BTFailure("Invalid state file contents")
            else:
                if i.next() != "Running torrents\n":
                    raise BTFailure("Invalid state file contents")
                while True:
                    line = i.next()
                    if line == 'Queued torrents\n':
                        break
                    t = decode_line(line)
                    if t is None:
                        continue
                    infohash, t = t
                    if t.dlpath is None:
                        raise BTFailure("Invalid state file contents")
                    t.state = RUN_QUEUED
                    self.running_torrents.append(infohash)
            while True:
                line = i.next()
                if line == 'Known torrents\n':
                    break
                t = decode_line(line)
                if t is None:
                    continue
                infohash, t = t
                if t.dlpath is None:
                    raise BTFailure("Invalid state file contents")
                t.state = QUEUED
                self.queue.append(infohash)
            while True:
                line = i.next()
                if line == 'End\n':
                    break
                t = decode_line(line)
                if t is None:
                    continue
                infohash, t = t
                if t.dlpath is None:
                    t.state = ASKING_LOCATION
                else:
                    t.state = KNOWN
                self.other_torrents.append(infohash)
        except StopIteration:
            raise BTFailure("Invalid state file contents")

    def _queue_loop(self):
        if self.doneflag.isSet():
            return
        self.rawserver.add_task(self._queue_loop, 20)
        now = bttime()
        if self.queue and self.starting_torrent is None:
            mintime = now - self.config['next_torrent_time'] * 60
            minratio = self.config['next_torrent_ratio'] / 100
        else:
            mintime = 0
            minratio = self.config['last_torrent_ratio'] / 100
            if not minratio:
                return
        for infohash in self.running_torrents:
            t = self.torrents[infohash]
            if t.state == RUN_QUEUED:
                continue
            totals = t.dl.get_total_transfer()
            # not updated for remaining torrents if one is stopped, who cares
            t.uptotal = t.uptotal_old + totals[0]
            t.downtotal = t.downtotal_old + totals[1]
            if t.finishtime is None or t.finishtime > now - 120:
                continue