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/* |
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* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd) |
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* |
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* Copyright (c) 1999-2016 ircd-hybrid development team |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation; either version 2 of the License, or |
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* (at your option) any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 |
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* USA |
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*/ |
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|
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/*! \file listener.c |
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* \brief Implementation for handling listening sockets. |
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* \version $Id$ |
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*/ |
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|
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#include "stdinc.h" |
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#include "list.h" |
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#include "listener.h" |
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#include "client.h" |
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#include "fdlist.h" |
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#include "irc_string.h" |
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#include "ircd.h" |
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#include "ircd_defs.h" |
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#include "s_bsd.h" |
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#include "conf.h" |
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#include "send.h" |
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#include "memory.h" |
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|
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#define TOOFAST_WARNING "ERROR :Your host is trying to (re)connect too fast -- throttled.\r\n" |
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#define DLINE_WARNING "ERROR :You have been D-lined.\r\n" |
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#define ALLINUSE_WARNING "ERROR :All connections in use\r\n" |
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|
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static dlink_list listener_list; |
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|
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const dlink_list * |
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listener_get_list(void) |
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{ |
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return &listener_list; |
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} |
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|
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static struct Listener * |
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listener_make(const int port, const struct irc_ssaddr *addr) |
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{ |
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struct Listener *listener = xcalloc(sizeof(struct Listener)); |
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|
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listener->port = port; |
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memcpy(&listener->addr, addr, sizeof(struct irc_ssaddr)); |
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|
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return listener; |
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} |
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|
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static void |
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listener_free(struct Listener *listener) |
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{ |
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dlinkDelete(&listener->node, &listener_list); |
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xfree(listener); |
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} |
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|
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/* |
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* listener_get_name - return displayable listener name and port |
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* returns "host.foo.org/6667" for a given listener |
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*/ |
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const char * |
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listener_get_name(const struct Listener *listener) |
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{ |
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static char buf[HOSTLEN + HOSTIPLEN + PORTNAMELEN + 4]; /* +4 for [,/,],\0 */ |
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|
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snprintf(buf, sizeof(buf), "%s[%s/%u]", me.name, |
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listener->name, listener->port); |
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return buf; |
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} |
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|
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void |
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listener_count_memory(unsigned int *count, size_t *bytes) |
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{ |
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(*count) = dlink_list_length(&listener_list); |
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(*bytes) = *count * sizeof(struct Listener); |
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} |
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|
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static void |
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listener_accept_connection(fde_t *pfd, void *data) |
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{ |
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static uintmax_t rate = 0; |
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struct irc_ssaddr addr; |
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int fd; |
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int pe; |
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struct Listener *const listener = data; |
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|
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assert(listener); |
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|
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/* There may be many reasons for error return, but |
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* in otherwise correctly working environment the |
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* probable cause is running out of file descriptors |
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* (EMFILE, ENFILE or others?). The man pages for |
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* accept don't seem to list these as possible, |
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* although it's obvious that it may happen here. |
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* Thus no specific errors are tested at this |
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* point, just assume that connections cannot |
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* be accepted until some old is closed first. |
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*/ |
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while ((fd = comm_accept(listener, &addr)) != -1) |
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{ |
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/* |
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* check for connection limit |
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*/ |
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if (number_fd > hard_fdlimit - 10) |
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{ |
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++ServerStats.is_ref; |
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sendto_realops_flags_ratelimited(&rate, "All connections in use. (%s)", |
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listener_get_name(listener)); |
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|
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if (!(listener->flags & LISTENER_SSL)) |
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send(fd, ALLINUSE_WARNING, sizeof(ALLINUSE_WARNING) - 1, 0); |
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|
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close(fd); |
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break; /* jump out and re-register a new io request */ |
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} |
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|
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/* |
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* Do an initial check we aren't connecting too fast or with too many |
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* from this IP... |
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*/ |
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if ((pe = conf_connect_allowed(&addr, addr.ss.ss_family))) |
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{ |
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++ServerStats.is_ref; |
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|
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if (!(listener->flags & LISTENER_SSL)) |
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{ |
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switch (pe) |
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{ |
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case BANNED_CLIENT: |
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send(fd, DLINE_WARNING, sizeof(DLINE_WARNING)-1, 0); |
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break; |
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case TOO_FAST: |
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send(fd, TOOFAST_WARNING, sizeof(TOOFAST_WARNING)-1, 0); |
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break; |
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} |
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} |
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|
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close(fd); |
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continue; /* drop the one and keep on clearing the queue */ |
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} |
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|
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++ServerStats.is_ac; |
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add_connection(listener, &addr, fd); |
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} |
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|
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/* Re-register a new IO request for the next accept .. */ |
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comm_setselect(&listener->fd, COMM_SELECT_READ, listener_accept_connection, |
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listener, 0); |
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} |
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|
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|
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/* |
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* inetport - create a listener socket in the AF_INET or AF_INET6 domain, |
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* bind it to the port given in 'port' and listen to it |
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* returns true (1) if successful false (0) on error. |
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* |
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* If the operating system has a define for SOMAXCONN, use it, otherwise |
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* use HYBRID_SOMAXCONN |
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*/ |
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#ifdef SOMAXCONN |
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#undef HYBRID_SOMAXCONN |
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#define HYBRID_SOMAXCONN SOMAXCONN |
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#endif |
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|
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static int |
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inetport(struct Listener *listener) |
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{ |
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struct irc_ssaddr lsin; |
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socklen_t opt = 1; |
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|
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memset(&lsin, 0, sizeof(lsin)); |
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memcpy(&lsin, &listener->addr, sizeof(lsin)); |
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|
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getnameinfo((const struct sockaddr *)&lsin, lsin.ss_len, listener->name, |
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sizeof(listener->name), NULL, 0, NI_NUMERICHOST); |
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|
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/* |
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* At first, open a new socket |
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*/ |
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if (comm_open(&listener->fd, listener->addr.ss.ss_family, SOCK_STREAM, 0, |
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"Listener socket") == -1) |
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{ |
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report_error(L_ALL, "opening listener socket %s:%s", |
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listener_get_name(listener), errno); |
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return 0; |
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} |
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|
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if (setsockopt(listener->fd.fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt))) |
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{ |
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report_error(L_ALL, "setting SO_REUSEADDR for listener %s:%s", |
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listener_get_name(listener), errno); |
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fd_close(&listener->fd); |
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return 0; |
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} |
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|
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/* |
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* Bind a port to listen for new connections if port is non-null, |
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* else assume it is already open and try get something from it. |
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*/ |
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lsin.ss_port = htons(listener->port); |
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|
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if (bind(listener->fd.fd, (struct sockaddr *)&lsin, lsin.ss_len)) |
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{ |
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report_error(L_ALL, "binding listener socket %s:%s", |
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listener_get_name(listener), errno); |
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fd_close(&listener->fd); |
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return 0; |
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} |
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|
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if (listen(listener->fd.fd, HYBRID_SOMAXCONN)) |
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{ |
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report_error(L_ALL, "listen failed for %s:%s", |
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listener_get_name(listener), errno); |
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fd_close(&listener->fd); |
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return 0; |
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} |
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|
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/* Listen completion events are READ events .. */ |
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|
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listener_accept_connection(&listener->fd, listener); |
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return 1; |
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} |
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|
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static struct Listener * |
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listener_find(int port, struct irc_ssaddr *addr) |
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{ |
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dlink_node *node; |
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struct Listener *listener = NULL; |
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struct Listener *last_closed = NULL; |
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|
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DLINK_FOREACH(node, listener_list.head) |
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{ |
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listener = node->data; |
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|
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if ((port == listener->port) && |
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(!memcmp(addr, &listener->addr, sizeof(struct irc_ssaddr)))) |
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{ |
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/* Try to return an open listener, otherwise reuse a closed one */ |
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if (!listener->fd.flags.open) |
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last_closed = listener; |
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else |
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return (listener); |
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} |
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} |
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|
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return (last_closed); |
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} |
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|
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/* |
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* close_listener - close a single listener |
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*/ |
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static void |
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listener_close(struct Listener *listener) |
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{ |
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if (listener->fd.flags.open) |
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fd_close(&listener->fd); |
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|
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listener->active = 0; |
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|
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if (listener->ref_count) |
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return; |
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|
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listener_free(listener); |
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} |
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|
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/* |
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* listener_close_marked - close and free all listeners that are not being used |
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*/ |
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void |
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listener_close_marked(void) |
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{ |
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dlink_node *node = NULL, *node_next = NULL; |
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|
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/* close all 'extra' listening ports we have */ |
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DLINK_FOREACH_SAFE(node, node_next, listener_list.head) |
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listener_close(node->data); |
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} |
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|
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void |
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listener_release(struct Listener *listener) |
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{ |
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assert(listener->ref_count > 0); |
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|
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if (--listener->ref_count == 0 && !listener->active) |
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listener_close(listener); |
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} |
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|
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/* |
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* listener_add- create a new listener |
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* port - the port number to listen on |
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* vhost_ip - if non-null must contain a valid IP address string in |
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* the format "255.255.255.255" |
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*/ |
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void |
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listener_add(int port, const char *vhost_ip, unsigned int flags) |
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{ |
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struct Listener *listener; |
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struct irc_ssaddr vaddr; |
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struct addrinfo hints, *res; |
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char portname[PORTNAMELEN + 1]; |
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static short int pass = 0; /* if ipv6 and no address specified we need to |
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have two listeners; one for each protocol. */ |
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|
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/* |
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* if no or invalid port in conf line, don't bother |
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*/ |
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if (!(port > 0 && port <= 0xFFFF)) |
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return; |
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|
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memset(&vaddr, 0, sizeof(vaddr)); |
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|
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/* Set up the hints structure */ |
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memset(&hints, 0, sizeof(hints)); |
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hints.ai_family = AF_UNSPEC; |
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hints.ai_socktype = SOCK_STREAM; |
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/* Get us ready for a bind() and don't bother doing dns lookup */ |
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hints.ai_flags = AI_PASSIVE | AI_NUMERICHOST; |
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|
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/* TBD: This makes no sense here at all. Needs to be reworked */ |
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|
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snprintf(portname, sizeof(portname), "%d", port); |
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getaddrinfo("::", portname, &hints, &res); |
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vaddr.ss.ss_family = AF_INET6; |
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|
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assert(res); |
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|
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memcpy((struct sockaddr*)&vaddr, res->ai_addr, res->ai_addrlen); |
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vaddr.ss_port = port; |
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vaddr.ss_len = res->ai_addrlen; |
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freeaddrinfo(res); |
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#ifdef MAKES_NO_SENSE |
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{ |
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struct sockaddr_in *v4 = (struct sockaddr_in*) &vaddr; |
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v4->sin_addr.s_addr = INADDR_ANY; |
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vaddr.ss.ss_family = AF_INET; |
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vaddr.ss_len = sizeof(struct sockaddr_in); |
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v4->sin_port = htons(port); |
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} |
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#endif |
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|
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snprintf(portname, PORTNAMELEN, "%d", port); |
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|
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if (!EmptyString(vhost_ip)) |
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{ |
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if (getaddrinfo(vhost_ip, portname, &hints, &res)) |
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return; |
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|
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assert(res); |
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|
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memcpy((struct sockaddr*)&vaddr, res->ai_addr, res->ai_addrlen); |
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vaddr.ss_port = port; |
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vaddr.ss_len = res->ai_addrlen; |
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freeaddrinfo(res); |
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} |
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else if (pass == 0) |
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{ |
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/* add the ipv4 listener if we havent already */ |
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pass = 1; |
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listener_add(port, "0.0.0.0", flags); |
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} |
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|
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pass = 0; |
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|
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if ((listener = listener_find(port, &vaddr))) |
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{ |
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listener->flags = flags; |
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|
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if (listener->fd.flags.open) |
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return; |
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} |
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else |
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{ |
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listener = listener_make(port, &vaddr); |
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dlinkAdd(listener, &listener->node, &listener_list); |
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listener->flags = flags; |
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} |
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|
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if (inetport(listener)) |
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listener->active = 1; |
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else |
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listener_close(listener); |
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} |