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/* |
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* ircd-hybrid: an advanced Internet Relay Chat Daemon(ircd). |
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* s_bsd_sigio.c: Linux Realtime SIGIO compatible network routines. |
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* |
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* Originally by Aaron Sethman <androsyn@ratbox.org> |
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* based upon: s_bsd_poll.c by Adrian Chadd <adrian@creative.net.au> |
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* Copyright (C) 2001-2002 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 |
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* USA |
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* |
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* $Id$ |
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*/ |
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|
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#ifndef _GNU_SOURCE |
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#define _GNU_SOURCE 1 /* Needed for F_SETSIG */ |
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#endif |
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|
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#include "stdinc.h" |
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#include <sys/poll.h> |
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#include "fdlist.h" |
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#include "hook.h" |
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#include "ircd.h" |
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#include "s_bsd.h" |
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#include "s_log.h" |
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|
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#define SIGIO_SIGNAL SIGRTMIN |
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|
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static pid_t my_pid; |
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static sigset_t our_sigset; |
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static struct pollfd *pollfds; |
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static int pollmax = -1; /* highest FD number */ |
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static dlink_node *fdlim_hook, *setupfd_hook; |
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|
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/* |
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* static void mask_our_signal(int s) |
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* |
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* Input: None |
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* Output: None |
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* Side Effects: Block our signal |
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*/ |
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static void |
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mask_our_signal() |
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{ |
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sigemptyset(&our_sigset); |
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sigaddset(&our_sigset, SIGIO_SIGNAL); |
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sigaddset(&our_sigset, SIGIO); |
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sigprocmask(SIG_BLOCK, &our_sigset, NULL); |
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} |
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|
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/* |
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* void setup_sigio_fd(int fd) |
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* |
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* Input: File descriptor |
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* Output: None |
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* Side Effect: Sets the FD up for SIGIO |
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*/ |
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static void * |
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setup_sigio_fd(va_list args) |
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{ |
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int fd = va_arg(args, int); |
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|
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fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_ASYNC); |
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fcntl(fd, F_SETSIG, SIGIO_SIGNAL); |
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fcntl(fd, F_SETOWN, my_pid); |
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|
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return pass_callback(setupfd_hook, fd); |
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} |
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|
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/* |
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* changing_fdlimit |
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* |
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* Resize pollfds array if necessary. |
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*/ |
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static void * |
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changing_fdlimit(va_list args) |
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{ |
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int old_fdlimit = hard_fdlimit; |
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|
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pass_callback(fdlim_hook, va_arg(args, int)); |
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|
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if (hard_fdlimit != old_fdlimit) |
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pollfds = MyRealloc(pollfds, sizeof(struct pollfd) * hard_fdlimit); |
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|
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return NULL; |
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} |
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|
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/* |
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* void init_netio(void) |
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* |
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* Input: None |
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* Output: None |
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* Side Effects: This is a needed exported function which will |
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* be called to initialise the network loop code. |
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*/ |
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void |
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init_netio(void) |
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{ |
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int fd; |
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|
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pollfds = MyMalloc(sizeof(struct pollfd) * hard_fdlimit); |
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|
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for (fd = 0; fd < hard_fdlimit; fd++) |
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pollfds[fd].fd = -1; |
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|
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setupfd_hook = install_hook(setup_socket_cb, setup_sigio_fd); |
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fdlim_hook = install_hook(fdlimit_cb, changing_fdlimit); |
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|
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my_pid = getpid(); |
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mask_our_signal(SIGIO_SIGNAL); |
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} |
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|
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/* |
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* find a spare slot in the fd list. We can optimise this out later! |
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* -- adrian |
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*/ |
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static inline int |
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poll_findslot(void) |
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{ |
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int i; |
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|
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for (i = 0; i < hard_fdlimit; i++) |
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{ |
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if (pollfds[i].fd == -1) |
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{ |
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/* MATCH!!#$*&$ */ |
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return i; |
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} |
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} |
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|
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assert(1 == 0); |
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/* NOTREACHED */ |
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return -1; |
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} |
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|
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/* |
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* comm_setselect |
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* |
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* This is a needed exported function which will be called to register |
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* and deregister interest in a pending IO state for a given FD. |
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*/ |
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void |
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comm_setselect(fde_t *F, unsigned int type, PF *handler, |
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void *client_data, time_t timeout) |
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{ |
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int new_events; |
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|
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if ((type & COMM_SELECT_READ)) |
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{ |
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F->read_handler = handler; |
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F->read_data = client_data; |
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} |
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|
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if ((type & COMM_SELECT_WRITE)) |
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{ |
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F->write_handler = handler; |
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F->write_data = client_data; |
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} |
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|
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new_events = (F->read_handler ? POLLRDNORM : 0) | |
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(F->write_handler ? POLLWRNORM : 0); |
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|
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if (timeout != 0) |
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F->timeout = CurrentTime + (timeout / 1000); |
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|
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if (new_events != F->evcache) |
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{ |
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if (new_events == 0) |
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{ |
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pollfds[F->comm_index].fd = -1; |
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pollfds[F->comm_index].revents = 0; |
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|
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if (pollmax == F->comm_index) |
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while (pollmax >= 0 && pollfds[pollmax].fd == -1) |
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pollmax--; |
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} |
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else |
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{ |
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if (F->evcache == 0) |
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{ |
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F->comm_index = poll_findslot(); |
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if (F->comm_index > pollmax) |
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pollmax = F->comm_index; |
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|
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pollfds[F->comm_index].fd = F->fd; |
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} |
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pollfds[F->comm_index].events = new_events; |
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pollfds[F->comm_index].revents = 0; |
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} |
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|
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F->evcache = new_events; |
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} |
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} |
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|
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/* |
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* comm_select |
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* |
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* Called to do the new-style IO, courtesy of squid (like most of this |
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* new IO code). This routine handles the stuff we've hidden in |
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* comm_setselect and fd_table[] and calls callbacks for IO ready |
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* events. |
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*/ |
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void |
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comm_select(void) |
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{ |
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static time_t last_rtsigqo_warning = 0; |
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struct timespec timeout; |
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struct siginfo si; |
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int i, revents, num; |
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fde_t *F; |
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PF *hdl; |
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|
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timeout.tv_sec = 0; |
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timeout.tv_nsec = 1000000 * SELECT_DELAY; |
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i = sigtimedwait(&our_sigset, &si, &timeout); |
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|
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set_time(); |
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|
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if (i != SIGIO) |
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{ |
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if (i > 0) |
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{ |
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F = lookup_fd(si.si_fd); |
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if (F == NULL || !F->flags.open) |
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return; |
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|
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if (si.si_band & (POLLRDNORM | POLLIN | POLLHUP | POLLERR)) |
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if ((hdl = F->read_handler) != NULL) |
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{ |
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F->read_handler = NULL; |
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hdl(F, F->read_data); |
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if (!F->flags.open) |
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return; |
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} |
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|
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if (si.si_band & (POLLWRNORM | POLLOUT | POLLHUP | POLLERR)) |
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if ((hdl = F->write_handler) != NULL) |
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{ |
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F->write_handler = NULL; |
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hdl(F, F->write_data); |
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if (!F->flags.open) |
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return; |
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} |
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|
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comm_setselect(F, 0, NULL, NULL, 0); |
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} |
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|
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return; |
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} |
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|
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/* RT signal queue overflowed.. */ |
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|
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if (CurrentTime - last_rtsigqo_warning >= 30) |
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{ |
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ilog(L_WARN, "Kernel RT Signal queue overflowed. " |
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"Is /proc/sys/kernel/rtsig-max too small?"); |
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last_rtsigqo_warning = CurrentTime; |
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} |
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|
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signal(SIGIO_SIGNAL, SIG_IGN); |
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signal(SIGIO_SIGNAL, SIG_DFL); |
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|
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/* ..try polling instead */ |
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|
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while ((num = poll(pollfds, pollmax + 1, 0)) < 0 && ignoreErrno(errno)) |
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; |
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|
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/* update current time again, eww.. */ |
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set_time(); |
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|
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for (i = 0; i <= pollmax && num > 0; i++) |
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{ |
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if ((revents = pollfds[i].revents) == 0 || pollfds[i].fd == -1) |
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continue; |
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num--; |
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|
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F = lookup_fd(pollfds[i].fd); |
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if (F == NULL || !F->flags.open) |
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continue; |
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|
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if (revents & (POLLRDNORM | POLLIN | POLLHUP | POLLERR)) |
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if ((hdl = F->read_handler) != NULL) |
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{ |
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F->read_handler = NULL; |
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hdl(F, F->read_data); |
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if (!F->flags.open) |
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continue; |
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} |
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|
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if (revents & (POLLWRNORM | POLLOUT | POLLHUP | POLLERR)) |
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if ((hdl = F->write_handler) != NULL) |
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{ |
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F->write_handler = NULL; |
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hdl(F, F->write_data); |
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if (!F->flags.open) |
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continue; |
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} |
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|
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comm_setselect(F, 0, NULL, NULL, 0); |
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} |
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|
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mask_our_signal(SIGIO_SIGNAL); |
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} |