PNG  IHDRxsBIT|d pHYs+tEXtSoftwarewww.inkscape.org<,tEXtComment File Manager

File Manager

Path: /opt/alt/python38/lib64/python3.8/

Viewing File: asynchat.py

# -*- Mode: Python; tab-width: 4 -*-
#       Id: asynchat.py,v 2.26 2000/09/07 22:29:26 rushing Exp
#       Author: Sam Rushing <rushing@nightmare.com>

# ======================================================================
# Copyright 1996 by Sam Rushing
#
#                         All Rights Reserved
#
# Permission to use, copy, modify, and distribute this software and
# its documentation for any purpose and without fee is hereby
# granted, provided that the above copyright notice appear in all
# copies and that both that copyright notice and this permission
# notice appear in supporting documentation, and that the name of Sam
# Rushing not be used in advertising or publicity pertaining to
# distribution of the software without specific, written prior
# permission.
#
# SAM RUSHING DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
# INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
# NO EVENT SHALL SAM RUSHING BE LIABLE FOR ANY SPECIAL, INDIRECT OR
# CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
# OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
# CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
# ======================================================================

r"""A class supporting chat-style (command/response) protocols.

This class adds support for 'chat' style protocols - where one side
sends a 'command', and the other sends a response (examples would be
the common internet protocols - smtp, nntp, ftp, etc..).

The handle_read() method looks at the input stream for the current
'terminator' (usually '\r\n' for single-line responses, '\r\n.\r\n'
for multi-line output), calling self.found_terminator() on its
receipt.

for example:
Say you build an async nntp client using this class.  At the start
of the connection, you'll have self.terminator set to '\r\n', in
order to process the single-line greeting.  Just before issuing a
'LIST' command you'll set it to '\r\n.\r\n'.  The output of the LIST
command will be accumulated (using your own 'collect_incoming_data'
method) up to the terminator, and then control will be returned to
you - by calling your self.found_terminator() method.
"""
import asyncore
from collections import deque


class async_chat(asyncore.dispatcher):
    """This is an abstract class.  You must derive from this class, and add
    the two methods collect_incoming_data() and found_terminator()"""

    # these are overridable defaults

    ac_in_buffer_size = 65536
    ac_out_buffer_size = 65536

    # we don't want to enable the use of encoding by default, because that is a
    # sign of an application bug that we don't want to pass silently

    use_encoding = 0
    encoding = 'latin-1'

    def __init__(self, sock=None, map=None):
        # for string terminator matching
        self.ac_in_buffer = b''

        # we use a list here rather than io.BytesIO for a few reasons...
        # del lst[:] is faster than bio.truncate(0)
        # lst = [] is faster than bio.truncate(0)
        self.incoming = []

        # we toss the use of the "simple producer" and replace it with
        # a pure deque, which the original fifo was a wrapping of
        self.producer_fifo = deque()
        asyncore.dispatcher.__init__(self, sock, map)

    def collect_incoming_data(self, data):
        raise NotImplementedError("must be implemented in subclass")

    def _collect_incoming_data(self, data):
        self.incoming.append(data)

    def _get_data(self):
        d = b''.join(self.incoming)
        del self.incoming[:]
        return d

    def found_terminator(self):
        raise NotImplementedError("must be implemented in subclass")

    def set_terminator(self, term):
        """Set the input delimiter.

        Can be a fixed string of any length, an integer, or None.
        """
        if isinstance(term, str) and self.use_encoding:
            term = bytes(term, self.encoding)
        elif isinstance(term, int) and term < 0:
            raise ValueError('the number of received bytes must be positive')
        self.terminator = term

    def get_terminator(self):
        return self.terminator

    # grab some more data from the socket,
    # throw it to the collector method,
    # check for the terminator,
    # if found, transition to the next state.

    def handle_read(self):

        try:
            data = self.recv(self.ac_in_buffer_size)
        except BlockingIOError:
            return
        except OSError as why:
            self.handle_error()
            return

        if isinstance(data, str) and self.use_encoding:
            data = bytes(str, self.encoding)
        self.ac_in_buffer = self.ac_in_buffer + data

        # Continue to search for self.terminator in self.ac_in_buffer,
        # while calling self.collect_incoming_data.  The while loop
        # is necessary because we might read several data+terminator
        # combos with a single recv(4096).

        while self.ac_in_buffer:
            lb = len(self.ac_in_buffer)
            terminator = self.get_terminator()
            if not terminator:
                # no terminator, collect it all
                self.collect_incoming_data(self.ac_in_buffer)
                self.ac_in_buffer = b''
            elif isinstance(terminator, int):
                # numeric terminator
                n = terminator
                if lb < n:
                    self.collect_incoming_data(self.ac_in_buffer)
                    self.ac_in_buffer = b''
                    self.terminator = self.terminator - lb
                else:
                    self.collect_incoming_data(self.ac_in_buffer[:n])
                    self.ac_in_buffer = self.ac_in_buffer[n:]
                    self.terminator = 0
                    self.found_terminator()
            else:
                # 3 cases:
                # 1) end of buffer matches terminator exactly:
                #    collect data, transition
                # 2) end of buffer matches some prefix:
                #    collect data to the prefix
                # 3) end of buffer does not match any prefix:
                #    collect data
                terminator_len = len(terminator)
                index = self.ac_in_buffer.find(terminator)
                if index != -1:
                    # we found the terminator
                    if index > 0:
                        # don't bother reporting the empty string
                        # (source of subtle bugs)
                        self.collect_incoming_data(self.ac_in_buffer[:index])
                    self.ac_in_buffer = self.ac_in_buffer[index+terminator_len:]
                    # This does the Right Thing if the terminator
                    # is changed here.
                    self.found_terminator()
                else:
                    # check for a prefix of the terminator
                    index = find_prefix_at_end(self.ac_in_buffer, terminator)
                    if index:
                        if index != lb:
                            # we found a prefix, collect up to the prefix
                            self.collect_incoming_data(self.ac_in_buffer[:-index])
                            self.ac_in_buffer = self.ac_in_buffer[-index:]
                        break
                    else:
                        # no prefix, collect it all
                        self.collect_incoming_data(self.ac_in_buffer)
                        self.ac_in_buffer = b''

    def handle_write(self):
        self.initiate_send()

    def handle_close(self):
        self.close()

    def push(self, data):
        if not isinstance(data, (bytes, bytearray, memoryview)):
            raise TypeError('data argument must be byte-ish (%r)',
                            type(data))
        sabs = self.ac_out_buffer_size
        if len(data) > sabs:
            for i in range(0, len(data), sabs):
                self.producer_fifo.append(data[i:i+sabs])
        else:
            self.producer_fifo.append(data)
        self.initiate_send()

    def push_with_producer(self, producer):
        self.producer_fifo.append(producer)
        self.initiate_send()

    def readable(self):
        "predicate for inclusion in the readable for select()"
        # cannot use the old predicate, it violates the claim of the
        # set_terminator method.

        # return (len(self.ac_in_buffer) <= self.ac_in_buffer_size)
        return 1

    def writable(self):
        "predicate for inclusion in the writable for select()"
        return self.producer_fifo or (not self.connected)

    def close_when_done(self):
        "automatically close this channel once the outgoing queue is empty"
        self.producer_fifo.append(None)

    def initiate_send(self):
        while self.producer_fifo and self.connected:
            first = self.producer_fifo[0]
            # handle empty string/buffer or None entry
            if not first:
                del self.producer_fifo[0]
                if first is None:
                    self.handle_close()
                    return

            # handle classic producer behavior
            obs = self.ac_out_buffer_size
            try:
                data = first[:obs]
            except TypeError:
                data = first.more()
                if data:
                    self.producer_fifo.appendleft(data)
                else:
                    del self.producer_fifo[0]
                continue

            if isinstance(data, str) and self.use_encoding:
                data = bytes(data, self.encoding)

            # send the data
            try:
                num_sent = self.send(data)
            except OSError:
                self.handle_error()
                return

            if num_sent:
                if num_sent < len(data) or obs < len(first):
                    self.producer_fifo[0] = first[num_sent:]
                else:
                    del self.producer_fifo[0]
            # we tried to send some actual data
            return

    def discard_buffers(self):
        # Emergencies only!
        self.ac_in_buffer = b''
        del self.incoming[:]
        self.producer_fifo.clear()


class simple_producer:

    def __init__(self, data, buffer_size=512):
        self.data = data
        self.buffer_size = buffer_size

    def more(self):
        if len(self.data) > self.buffer_size:
            result = self.data[:self.buffer_size]
            self.data = self.data[self.buffer_size:]
            return result
        else:
            result = self.data
            self.data = b''
            return result


# Given 'haystack', see if any prefix of 'needle' is at its end.  This
# assumes an exact match has already been checked.  Return the number of
# characters matched.
# for example:
# f_p_a_e("qwerty\r", "\r\n") => 1
# f_p_a_e("qwertydkjf", "\r\n") => 0
# f_p_a_e("qwerty\r\n", "\r\n") => <undefined>

# this could maybe be made faster with a computed regex?
# [answer: no; circa Python-2.0, Jan 2001]
# new python:   28961/s
# old python:   18307/s
# re:        12820/s
# regex:     14035/s

def find_prefix_at_end(haystack, needle):
    l = len(needle) - 1
    while l and not haystack.endswith(needle[:l]):
        l -= 1
    return l
b IDATxytVսϓ22 A@IR :hCiZ[v*E:WũZA ^dQeQ @ !jZ'>gsV仿$|?g)&x-EIENT ;@xT.i%-X}SvS5.r/UHz^_$-W"w)Ɗ/@Z &IoX P$K}JzX:;` &, ŋui,e6mX ԵrKb1ԗ)DADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADADA݀!I*]R;I2$eZ#ORZSrr6mteffu*((Pu'v{DIߔ4^pIm'77WEEE;vƎ4-$]'RI{\I&G :IHJ DWBB=\WR޽m o$K(V9ABB.}jѢv`^?IOȅ} ڶmG}T#FJ`56$-ھ}FI&v;0(h;Б38CӧOWf!;A i:F_m9s&|q%=#wZprrrla A &P\\СC[A#! {olF} `E2}MK/vV)i{4BffV\|ۭX`b@kɶ@%i$K z5zhmX[IXZ` 'b%$r5M4º/l ԃߖxhʔ)[@=} K6IM}^5k㏷݆z ΗÿO:gdGBmyT/@+Vɶ纽z񕏵l.y޴it뭷zV0[Y^>Wsqs}\/@$(T7f.InݺiR$푔n.~?H))\ZRW'Mo~v Ov6oԃxz! S,&xm/yɞԟ?'uaSѽb,8GלKboi&3t7Y,)JJ c[nzӳdE&KsZLӄ I?@&%ӟ۶mSMMњ0iؐSZ,|J+N ~,0A0!5%Q-YQQa3}$_vVrf9f?S8`zDADADADADADADADADAdqP,تmMmg1V?rSI꒟]u|l RCyEf٢9 jURbztѰ!m5~tGj2DhG*{H9)꒟ר3:(+3\?/;TUݭʴ~S6lڧUJ*i$d(#=Yݺd{,p|3B))q:vN0Y.jkק6;SɶVzHJJЀ-utѹսk>QUU\޲~]fFnK?&ߡ5b=z9)^|u_k-[y%ZNU6 7Mi:]ۦtk[n X(e6Bb."8cۭ|~teuuw|ήI-5"~Uk;ZicEmN/:]M> cQ^uiƞ??Ңpc#TUU3UakNwA`:Y_V-8.KKfRitv޲* 9S6ֿj,ՃNOMߤ]z^fOh|<>@Å5 _/Iu?{SY4hK/2]4%it5q]GGe2%iR| W&f*^]??vq[LgE_3f}Fxu~}qd-ږFxu~I N>\;͗O֊:̗WJ@BhW=y|GgwܷH_NY?)Tdi'?խwhlmQi !SUUsw4kӺe4rfxu-[nHtMFj}H_u~w>)oV}(T'ebʒv3_[+vn@Ȭ\S}ot}w=kHFnxg S 0eޢm~l}uqZfFoZuuEg `zt~? b;t%>WTkķh[2eG8LIWx,^\thrl^Ϊ{=dž<}qV@ ⠨Wy^LF_>0UkDuʫuCs$)Iv:IK;6ֲ4{^6եm+l3>݆uM 9u?>Zc }g~qhKwڭeFMM~pМuqǿz6Tb@8@Y|jx](^]gf}M"tG -w.@vOqh~/HII`S[l.6nØXL9vUcOoB\xoǤ'T&IǍQw_wpv[kmO{w~>#=P1Pɞa-we:iǏlHo׈꒟f9SzH?+shk%Fs:qVhqY`jvO'ρ?PyX3lх]˾uV{ݞ]1,MzYNW~̈́ joYn}ȚF߾׮mS]F z+EDxm/d{F{-W-4wY듏:??_gPf ^3ecg ҵs8R2מz@TANGj)}CNi/R~}c:5{!ZHӋӾ6}T]G]7W6^n 9*,YqOZj:P?Q DFL|?-^.Ɵ7}fFh׶xe2Pscz1&5\cn[=Vn[ĶE鎀uˌd3GII k;lNmشOuuRVfBE]ۣeӶu :X-[(er4~LHi6:Ѻ@ԅrST0trk%$Č0ez" *z"T/X9|8.C5Feg}CQ%͞ˣJvL/?j^h&9xF`њZ(&yF&Iݻfg#W;3^{Wo^4'vV[[K';+mӍִ]AC@W?1^{එyh +^]fm~iԵ]AB@WTk̏t uR?l.OIHiYyԶ]Aˀ7c:q}ힽaf6Z~қm(+sK4{^6}T*UUu]n.:kx{:2 _m=sAߤU@?Z-Vކеz왍Nэ{|5 pڶn b p-@sPg]0G7fy-M{GCF'%{4`=$-Ge\ eU:m+Zt'WjO!OAF@ik&t݆ϥ_ e}=]"Wz_.͜E3leWFih|t-wZۍ-uw=6YN{6|} |*={Ѽn.S.z1zjۻTH]흾 DuDvmvK.`V]yY~sI@t?/ϓ. m&["+P?MzovVЫG3-GRR[(!!\_,^%?v@ҵő m`Y)tem8GMx.))A]Y i`ViW`?^~!S#^+ѽGZj?Vģ0.))A꨷lzL*]OXrY`DBBLOj{-MH'ii-ϰ ok7^ )쭡b]UXSְmռY|5*cֽk0B7镹%ڽP#8nȎq}mJr23_>lE5$iwui+ H~F`IjƵ@q \ @#qG0".0" l`„.0! ,AQHN6qzkKJ#o;`Xv2>,tێJJ7Z/*A .@fفjMzkg @TvZH3Zxu6Ra'%O?/dQ5xYkU]Rֽkق@DaS^RSּ5|BeHNN͘p HvcYcC5:y #`οb;z2.!kr}gUWkyZn=f Pvsn3p~;4p˚=ē~NmI] ¾ 0lH[_L hsh_ғߤc_њec)g7VIZ5yrgk̞W#IjӪv>՞y睝M8[|]\շ8M6%|@PZڨI-m>=k='aiRo-x?>Q.}`Ȏ:Wsmu u > .@,&;+!!˱tﭧDQwRW\vF\~Q7>spYw$%A~;~}6¾ g&if_=j,v+UL1(tWake:@Ș>j$Gq2t7S?vL|]u/ .(0E6Mk6hiۺzښOrifޱxm/Gx> Lal%%~{lBsR4*}{0Z/tNIɚpV^#Lf:u@k#RSu =S^ZyuR/.@n&΃z~B=0eg뺆#,Þ[B/?H uUf7y Wy}Bwegל`Wh(||`l`.;Ws?V@"c:iɍL֯PGv6zctM̠':wuW;d=;EveD}9J@B(0iհ bvP1{\P&G7D޴Iy_$-Qjm~Yrr&]CDv%bh|Yzni_ˆR;kg}nJOIIwyuL}{ЌNj}:+3Y?:WJ/N+Rzd=hb;dj͒suݔ@NKMԄ jqzC5@y°hL m;*5ezᕏ=ep XL n?מ:r`۵tŤZ|1v`V뽧_csج'ߤ%oTuumk%%%h)uy]Nk[n 'b2 l.=͜E%gf$[c;s:V-͞WߤWh-j7]4=F-X]>ZLSi[Y*We;Zan(ӇW|e(HNNP5[= r4tP &0<pc#`vTNV GFqvTi*Tyam$ߏWyE*VJKMTfFw>'$-ؽ.Ho.8c"@DADADADADADADADADA~j*֘,N;Pi3599h=goضLgiJ5փy~}&Zd9p֚ e:|hL``b/d9p? fgg+%%hMgXosج, ΩOl0Zh=xdjLmhݻoO[g_l,8a]٭+ӧ0$I]c]:粹:Teꢢ"5a^Kgh,&= =՟^߶“ߢE ܹS J}I%:8 IDAT~,9/ʃPW'Mo}zNƍ쨓zPbNZ~^z=4mswg;5 Y~SVMRXUյڱRf?s:w ;6H:ºi5-maM&O3;1IKeamZh͛7+##v+c ~u~ca]GnF'ټL~PPPbn voC4R,ӟgg %hq}@#M4IÇ Oy^xMZx ) yOw@HkN˖-Sǎmb]X@n+i͖!++K3gd\$mt$^YfJ\8PRF)77Wא!Cl$i:@@_oG I{$# 8磌ŋ91A (Im7֭>}ߴJq7ޗt^ -[ԩSj*}%]&' -ɓ'ꫯVzzvB#;a 7@GxI{j޼ƌ.LÇWBB7`O"I$/@R @eee@۷>}0,ɒ2$53Xs|cS~rpTYYY} kHc %&k.], @ADADADADADADADADA@lT<%''*Lo^={رc5h %$+CnܸQ3fҥK}vUVVs9G R,_{xˇ3o߾;TTTd}馛]uuuG~iԩ@4bnvmvfϞ /Peeeq}}za I~,誫{UWW뮻}_~YƍSMMMYχ֝waw\ďcxꩧtEƍկ_?۷5@u?1kNׯWzz/wy>}zj3 k(ٺuq_Zvf̘:~ ABQ&r|!%KҥKgԞ={<_X-z !CyFUUz~ ABQIIIjݺW$UXXDٳZ~ ABQƍecW$<(~<RSSvZujjjԧOZQu@4 8m&&&jԩg$ď1h ͟?_{768@g =@`)))5o6m3)ѣƌJ;wҿUTT /KZR{~a=@0o<*狔iFɶ[ˎ;T]]OX@?K.ۈxN pppppppppppppppppPfl߾] ,{ァk۶mڿo5BTӦMӴiӴ|r DB2e|An!Dy'tkΝ[A $***t5' "!駟oaDnΝ:t֭[gDШQ06qD;@ x M6v(PiizmZ4ew"@̴ixf [~-Fٱc&IZ2|n!?$@{[HTɏ#@hȎI# _m(F /6Z3z'\r,r!;w2Z3j=~GY7"I$iI.p_"?pN`y DD?: _  Gÿab7J !Bx@0 Bo cG@`1C[@0G @`0C_u V1 aCX>W ` | `!<S `"<. `#c`?cAC4 ?c p#~@0?:08&_MQ1J h#?/`7;I  q 7a wQ A 1 Hp !#<8/#@1Ul7=S=K.4Z?E_$i@!1!E4?`P_  @Bă10#: "aU,xbFY1 [n|n #'vEH:`xb #vD4Y hi.i&EΖv#O H4IŶ}:Ikh @tZRF#(tXҙzZ ?I3l7q@õ|ۍ1,GpuY Ꮿ@hJv#xxk$ v#9 5 }_$c S#=+"K{F*m7`#%H:NRSp6I?sIՖ{Ap$I$I:QRv2$Z @UJ*$]<FO4IENDB`