danicoin/external/unbound/util/winsock_event.c
2014-10-05 23:44:31 +02:00

697 lines
21 KiB
C

/*
* util/winsock_event.c - implementation of the unbound winsock event handler.
*
* Copyright (c) 2008, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the NLNET LABS nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* \file
* Implementation of the unbound WinSock2 API event notification handler
* for the Windows port.
*/
#include "config.h"
#ifdef USE_WINSOCK
#include <signal.h>
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#include <sys/time.h>
#include "util/winsock_event.h"
#include "util/fptr_wlist.h"
int mini_ev_cmp(const void* a, const void* b)
{
const struct event *e = (const struct event*)a;
const struct event *f = (const struct event*)b;
if(e->ev_timeout.tv_sec < f->ev_timeout.tv_sec)
return -1;
if(e->ev_timeout.tv_sec > f->ev_timeout.tv_sec)
return 1;
if(e->ev_timeout.tv_usec < f->ev_timeout.tv_usec)
return -1;
if(e->ev_timeout.tv_usec > f->ev_timeout.tv_usec)
return 1;
if(e < f)
return -1;
if(e > f)
return 1;
return 0;
}
/** set time */
static int
settime(struct event_base* base)
{
if(gettimeofday(base->time_tv, NULL) < 0) {
return -1;
}
#ifndef S_SPLINT_S
*base->time_secs = (time_t)base->time_tv->tv_sec;
#endif
return 0;
}
#ifdef UNBOUND_DEBUG
/**
* Find a fd in the list of items.
* Note that not all items have a fd associated (those are -1).
* Signals are stored separately, and not searched.
* @param base: event base to look in.
* @param fd: what socket to look for.
* @return the index in the array, or -1 on failure.
*/
static int
find_fd(struct event_base* base, int fd)
{
int i;
for(i=0; i<base->max; i++) {
if(base->items[i]->ev_fd == fd)
return i;
}
return -1;
}
#endif
/** Find ptr in base array */
static void
zero_waitfor(WSAEVENT waitfor[], WSAEVENT x)
{
int i;
for(i=0; i<WSK_MAX_ITEMS; i++) {
if(waitfor[i] == x)
waitfor[i] = 0;
}
}
void *event_init(time_t* time_secs, struct timeval* time_tv)
{
struct event_base* base = (struct event_base*)malloc(
sizeof(struct event_base));
if(!base)
return NULL;
memset(base, 0, sizeof(*base));
base->time_secs = time_secs;
base->time_tv = time_tv;
if(settime(base) < 0) {
event_base_free(base);
return NULL;
}
base->items = (struct event**)calloc(WSK_MAX_ITEMS,
sizeof(struct event*));
if(!base->items) {
event_base_free(base);
return NULL;
}
base->cap = WSK_MAX_ITEMS;
base->max = 0;
base->times = rbtree_create(mini_ev_cmp);
if(!base->times) {
event_base_free(base);
return NULL;
}
base->signals = (struct event**)calloc(MAX_SIG, sizeof(struct event*));
if(!base->signals) {
event_base_free(base);
return NULL;
}
base->tcp_stickies = 0;
base->tcp_reinvigorated = 0;
verbose(VERB_CLIENT, "winsock_event inited");
return base;
}
const char *event_get_version(void)
{
return "winsock-event-"PACKAGE_VERSION;
}
const char *event_get_method(void)
{
return "WSAWaitForMultipleEvents";
}
/** call timeouts handlers, and return how long to wait for next one or -1 */
static void handle_timeouts(struct event_base* base, struct timeval* now,
struct timeval* wait)
{
struct event* p;
#ifndef S_SPLINT_S
wait->tv_sec = (time_t)-1;
#endif
verbose(VERB_CLIENT, "winsock_event handle_timeouts");
while((rbnode_t*)(p = (struct event*)rbtree_first(base->times))
!=RBTREE_NULL) {
#ifndef S_SPLINT_S
if(p->ev_timeout.tv_sec > now->tv_sec ||
(p->ev_timeout.tv_sec==now->tv_sec &&
p->ev_timeout.tv_usec > now->tv_usec)) {
/* there is a next larger timeout. wait for it */
wait->tv_sec = p->ev_timeout.tv_sec - now->tv_sec;
if(now->tv_usec > p->ev_timeout.tv_usec) {
wait->tv_sec--;
wait->tv_usec = 1000000 - (now->tv_usec -
p->ev_timeout.tv_usec);
} else {
wait->tv_usec = p->ev_timeout.tv_usec
- now->tv_usec;
}
verbose(VERB_CLIENT, "winsock_event wait=" ARG_LL "d.%6.6d",
(long long)wait->tv_sec, (int)wait->tv_usec);
return;
}
#endif
/* event times out, remove it */
(void)rbtree_delete(base->times, p);
p->ev_events &= ~EV_TIMEOUT;
fptr_ok(fptr_whitelist_event(p->ev_callback));
(*p->ev_callback)(p->ev_fd, EV_TIMEOUT, p->ev_arg);
}
verbose(VERB_CLIENT, "winsock_event wait=(-1)");
}
/** handle is_signal events and see if signalled */
static void handle_signal(struct event* ev)
{
DWORD ret;
log_assert(ev->is_signal && ev->hEvent);
/* see if the event is signalled */
ret = WSAWaitForMultipleEvents(1, &ev->hEvent, 0 /* any object */,
0 /* return immediately */, 0 /* not alertable for IOcomple*/);
if(ret == WSA_WAIT_IO_COMPLETION || ret == WSA_WAIT_FAILED) {
log_err("WSAWaitForMultipleEvents(signal) failed: %s",
wsa_strerror(WSAGetLastError()));
return;
}
if(ret == WSA_WAIT_TIMEOUT) {
/* not signalled */
return;
}
/* reset the signal */
if(!WSAResetEvent(ev->hEvent))
log_err("WSAResetEvent failed: %s",
wsa_strerror(WSAGetLastError()));
/* do the callback (which may set the signal again) */
fptr_ok(fptr_whitelist_event(ev->ev_callback));
(*ev->ev_callback)(ev->ev_fd, ev->ev_events, ev->ev_arg);
}
/** call select and callbacks for that */
static int handle_select(struct event_base* base, struct timeval* wait)
{
DWORD timeout = 0; /* in milliseconds */
DWORD ret;
struct event* eventlist[WSK_MAX_ITEMS];
WSANETWORKEVENTS netev;
int i, numwait = 0, startidx = 0, was_timeout = 0;
int newstickies = 0;
struct timeval nultm;
verbose(VERB_CLIENT, "winsock_event handle_select");
#ifndef S_SPLINT_S
if(wait->tv_sec==(time_t)-1)
wait = NULL;
if(wait)
timeout = wait->tv_sec*1000 + wait->tv_usec/1000;
if(base->tcp_stickies) {
wait = &nultm;
nultm.tv_sec = 0;
nultm.tv_usec = 0;
timeout = 0; /* no waiting, we have sticky events */
}
#endif
/* prepare event array */
for(i=0; i<base->max; i++) {
if(base->items[i]->ev_fd == -1 && !base->items[i]->is_signal)
continue; /* skip timer only events */
eventlist[numwait] = base->items[i];
base->waitfor[numwait++] = base->items[i]->hEvent;
if(numwait == WSK_MAX_ITEMS)
break; /* sanity check */
}
log_assert(numwait <= WSA_MAXIMUM_WAIT_EVENTS);
verbose(VERB_CLIENT, "winsock_event bmax=%d numwait=%d wait=%x "
"timeout=%d", base->max, numwait, (int)wait, (int)timeout);
/* do the wait */
if(numwait == 0) {
/* WSAWaitFor.. doesn't like 0 event objects */
if(wait) {
Sleep(timeout);
}
was_timeout = 1;
} else {
ret = WSAWaitForMultipleEvents(numwait, base->waitfor,
0 /* do not wait for all, just one will do */,
wait?timeout:WSA_INFINITE,
0); /* we are not alertable (IO completion events) */
if(ret == WSA_WAIT_IO_COMPLETION) {
log_err("WSAWaitForMultipleEvents failed: WSA_WAIT_IO_COMPLETION");
return -1;
} else if(ret == WSA_WAIT_FAILED) {
log_err("WSAWaitForMultipleEvents failed: %s",
wsa_strerror(WSAGetLastError()));
return -1;
} else if(ret == WSA_WAIT_TIMEOUT) {
was_timeout = 1;
} else
startidx = ret - WSA_WAIT_EVENT_0;
}
verbose(VERB_CLIENT, "winsock_event wake was_timeout=%d startidx=%d",
was_timeout, startidx);
/* get new time after wait */
if(settime(base) < 0)
return -1;
/* callbacks */
if(base->tcp_stickies)
startidx = 0; /* process all events, some are sticky */
for(i=startidx; i<numwait; i++)
eventlist[i]->just_checked = 1;
verbose(VERB_CLIENT, "winsock_event signals");
for(i=startidx; i<numwait; i++) {
if(!base->waitfor[i])
continue; /* was deleted */
if(eventlist[i]->is_signal) {
eventlist[i]->just_checked = 0;
handle_signal(eventlist[i]);
}
}
/* early exit - do not process network, exit quickly */
if(base->need_to_exit)
return 0;
verbose(VERB_CLIENT, "winsock_event net");
for(i=startidx; i<numwait; i++) {
short bits = 0;
/* eventlist[i] fired */
/* see if eventlist[i] is still valid and just checked from
* WSAWaitForEvents */
if(!base->waitfor[i])
continue; /* was deleted */
if(!eventlist[i]->just_checked)
continue; /* added by other callback */
if(eventlist[i]->is_signal)
continue; /* not a network event at all */
eventlist[i]->just_checked = 0;
if(WSAEnumNetworkEvents(eventlist[i]->ev_fd,
base->waitfor[i], /* reset the event handle */
/*NULL,*/ /* do not reset the event handle */
&netev) != 0) {
log_err("WSAEnumNetworkEvents failed: %s",
wsa_strerror(WSAGetLastError()));
return -1;
}
if((netev.lNetworkEvents & FD_READ)) {
if(netev.iErrorCode[FD_READ_BIT] != 0)
verbose(VERB_ALGO, "FD_READ_BIT error: %s",
wsa_strerror(netev.iErrorCode[FD_READ_BIT]));
bits |= EV_READ;
}
if((netev.lNetworkEvents & FD_WRITE)) {
if(netev.iErrorCode[FD_WRITE_BIT] != 0)
verbose(VERB_ALGO, "FD_WRITE_BIT error: %s",
wsa_strerror(netev.iErrorCode[FD_WRITE_BIT]));
bits |= EV_WRITE;
}
if((netev.lNetworkEvents & FD_CONNECT)) {
if(netev.iErrorCode[FD_CONNECT_BIT] != 0)
verbose(VERB_ALGO, "FD_CONNECT_BIT error: %s",
wsa_strerror(netev.iErrorCode[FD_CONNECT_BIT]));
bits |= EV_READ;
bits |= EV_WRITE;
}
if((netev.lNetworkEvents & FD_ACCEPT)) {
if(netev.iErrorCode[FD_ACCEPT_BIT] != 0)
verbose(VERB_ALGO, "FD_ACCEPT_BIT error: %s",
wsa_strerror(netev.iErrorCode[FD_ACCEPT_BIT]));
bits |= EV_READ;
}
if((netev.lNetworkEvents & FD_CLOSE)) {
if(netev.iErrorCode[FD_CLOSE_BIT] != 0)
verbose(VERB_ALGO, "FD_CLOSE_BIT error: %s",
wsa_strerror(netev.iErrorCode[FD_CLOSE_BIT]));
bits |= EV_READ;
bits |= EV_WRITE;
}
if(eventlist[i]->is_tcp && eventlist[i]->stick_events) {
verbose(VERB_ALGO, "winsock %d pass sticky %s%s",
eventlist[i]->ev_fd,
(eventlist[i]->old_events&EV_READ)?"EV_READ":"",
(eventlist[i]->old_events&EV_WRITE)?"EV_WRITE":"");
bits |= eventlist[i]->old_events;
}
if(eventlist[i]->is_tcp && bits) {
eventlist[i]->old_events = bits;
eventlist[i]->stick_events = 1;
if((eventlist[i]->ev_events & bits)) {
newstickies = 1;
}
verbose(VERB_ALGO, "winsock %d store sticky %s%s",
eventlist[i]->ev_fd,
(eventlist[i]->old_events&EV_READ)?"EV_READ":"",
(eventlist[i]->old_events&EV_WRITE)?"EV_WRITE":"");
}
if((bits & eventlist[i]->ev_events)) {
verbose(VERB_ALGO, "winsock event callback %p fd=%d "
"%s%s%s%s%s ; %s%s%s",
eventlist[i], eventlist[i]->ev_fd,
(netev.lNetworkEvents&FD_READ)?" FD_READ":"",
(netev.lNetworkEvents&FD_WRITE)?" FD_WRITE":"",
(netev.lNetworkEvents&FD_CONNECT)?
" FD_CONNECT":"",
(netev.lNetworkEvents&FD_ACCEPT)?
" FD_ACCEPT":"",
(netev.lNetworkEvents&FD_CLOSE)?" FD_CLOSE":"",
(bits&EV_READ)?" EV_READ":"",
(bits&EV_WRITE)?" EV_WRITE":"",
(bits&EV_TIMEOUT)?" EV_TIMEOUT":"");
fptr_ok(fptr_whitelist_event(
eventlist[i]->ev_callback));
(*eventlist[i]->ev_callback)(eventlist[i]->ev_fd,
bits & eventlist[i]->ev_events,
eventlist[i]->ev_arg);
}
if(eventlist[i]->is_tcp && bits)
verbose(VERB_ALGO, "winsock %d got sticky %s%s",
eventlist[i]->ev_fd,
(eventlist[i]->old_events&EV_READ)?"EV_READ":"",
(eventlist[i]->old_events&EV_WRITE)?"EV_WRITE":"");
}
verbose(VERB_CLIENT, "winsock_event net");
if(base->tcp_reinvigorated) {
verbose(VERB_CLIENT, "winsock_event reinvigorated");
base->tcp_reinvigorated = 0;
newstickies = 1;
}
base->tcp_stickies = newstickies;
verbose(VERB_CLIENT, "winsock_event handle_select end");
return 0;
}
int event_base_dispatch(struct event_base *base)
{
struct timeval wait;
if(settime(base) < 0)
return -1;
while(!base->need_to_exit)
{
/* see if timeouts need handling */
handle_timeouts(base, base->time_tv, &wait);
if(base->need_to_exit)
return 0;
/* do select */
if(handle_select(base, &wait) < 0) {
if(base->need_to_exit)
return 0;
return -1;
}
}
return 0;
}
int event_base_loopexit(struct event_base *base,
struct timeval * ATTR_UNUSED(tv))
{
verbose(VERB_CLIENT, "winsock_event loopexit");
base->need_to_exit = 1;
return 0;
}
void event_base_free(struct event_base *base)
{
verbose(VERB_CLIENT, "winsock_event event_base_free");
if(!base)
return;
if(base->items)
free(base->items);
if(base->times)
free(base->times);
if(base->signals)
free(base->signals);
free(base);
}
void event_set(struct event *ev, int fd, short bits,
void (*cb)(int, short, void *), void *arg)
{
ev->node.key = ev;
ev->ev_fd = fd;
ev->ev_events = bits;
ev->ev_callback = cb;
fptr_ok(fptr_whitelist_event(ev->ev_callback));
ev->ev_arg = arg;
ev->just_checked = 0;
ev->added = 0;
}
int event_base_set(struct event_base *base, struct event *ev)
{
ev->ev_base = base;
ev->old_events = 0;
ev->stick_events = 0;
ev->added = 0;
return 0;
}
int event_add(struct event *ev, struct timeval *tv)
{
verbose(VERB_ALGO, "event_add %p added=%d fd=%d tv=" ARG_LL "d %s%s%s",
ev, ev->added, ev->ev_fd,
(tv?(long long)tv->tv_sec*1000+(long long)tv->tv_usec/1000:-1),
(ev->ev_events&EV_READ)?" EV_READ":"",
(ev->ev_events&EV_WRITE)?" EV_WRITE":"",
(ev->ev_events&EV_TIMEOUT)?" EV_TIMEOUT":"");
if(ev->added)
event_del(ev);
log_assert(ev->ev_fd==-1 || find_fd(ev->ev_base, ev->ev_fd) == -1);
ev->is_tcp = 0;
ev->is_signal = 0;
ev->just_checked = 0;
if((ev->ev_events&(EV_READ|EV_WRITE)) && ev->ev_fd != -1) {
BOOL b=0;
int t, l;
long events = 0;
if(ev->ev_base->max == ev->ev_base->cap)
return -1;
ev->idx = ev->ev_base->max++;
ev->ev_base->items[ev->idx] = ev;
if( (ev->ev_events&EV_READ) )
events |= FD_READ;
if( (ev->ev_events&EV_WRITE) )
events |= FD_WRITE;
l = sizeof(t);
if(getsockopt(ev->ev_fd, SOL_SOCKET, SO_TYPE,
(void*)&t, &l) != 0)
log_err("getsockopt(SO_TYPE) failed: %s",
wsa_strerror(WSAGetLastError()));
if(t == SOCK_STREAM) {
/* TCP socket */
ev->is_tcp = 1;
events |= FD_CLOSE;
if( (ev->ev_events&EV_WRITE) )
events |= FD_CONNECT;
l = sizeof(b);
if(getsockopt(ev->ev_fd, SOL_SOCKET, SO_ACCEPTCONN,
(void*)&b, &l) != 0)
log_err("getsockopt(SO_ACCEPTCONN) failed: %s",
wsa_strerror(WSAGetLastError()));
if(b) /* TCP accept socket */
events |= FD_ACCEPT;
}
ev->hEvent = WSACreateEvent();
if(ev->hEvent == WSA_INVALID_EVENT)
log_err("WSACreateEvent failed: %s",
wsa_strerror(WSAGetLastError()));
/* automatically sets fd to nonblocking mode.
* nonblocking cannot be disabled, until wsaES(fd, NULL, 0) */
if(WSAEventSelect(ev->ev_fd, ev->hEvent, events) != 0) {
log_err("WSAEventSelect failed: %s",
wsa_strerror(WSAGetLastError()));
}
if(ev->is_tcp && ev->stick_events &&
(ev->ev_events & ev->old_events)) {
/* go to processing the sticky event right away */
ev->ev_base->tcp_reinvigorated = 1;
}
}
if(tv && (ev->ev_events&EV_TIMEOUT)) {
#ifndef S_SPLINT_S
struct timeval *now = ev->ev_base->time_tv;
ev->ev_timeout.tv_sec = tv->tv_sec + now->tv_sec;
ev->ev_timeout.tv_usec = tv->tv_usec + now->tv_usec;
while(ev->ev_timeout.tv_usec > 1000000) {
ev->ev_timeout.tv_usec -= 1000000;
ev->ev_timeout.tv_sec++;
}
#endif
(void)rbtree_insert(ev->ev_base->times, &ev->node);
}
ev->added = 1;
return 0;
}
int event_del(struct event *ev)
{
verbose(VERB_ALGO, "event_del %p added=%d fd=%d tv=" ARG_LL "d %s%s%s",
ev, ev->added, ev->ev_fd,
(ev->ev_events&EV_TIMEOUT)?(long long)ev->ev_timeout.tv_sec*1000+
(long long)ev->ev_timeout.tv_usec/1000:-1,
(ev->ev_events&EV_READ)?" EV_READ":"",
(ev->ev_events&EV_WRITE)?" EV_WRITE":"",
(ev->ev_events&EV_TIMEOUT)?" EV_TIMEOUT":"");
if(!ev->added)
return 0;
log_assert(ev->added);
if((ev->ev_events&EV_TIMEOUT))
(void)rbtree_delete(ev->ev_base->times, &ev->node);
if((ev->ev_events&(EV_READ|EV_WRITE)) && ev->ev_fd != -1) {
log_assert(ev->ev_base->max > 0);
/* remove item and compact the list */
ev->ev_base->items[ev->idx] =
ev->ev_base->items[ev->ev_base->max-1];
ev->ev_base->items[ev->ev_base->max-1] = NULL;
ev->ev_base->max--;
if(ev->idx < ev->ev_base->max)
ev->ev_base->items[ev->idx]->idx = ev->idx;
zero_waitfor(ev->ev_base->waitfor, ev->hEvent);
if(WSAEventSelect(ev->ev_fd, ev->hEvent, 0) != 0)
log_err("WSAEventSelect(disable) failed: %s",
wsa_strerror(WSAGetLastError()));
if(!WSACloseEvent(ev->hEvent))
log_err("WSACloseEvent failed: %s",
wsa_strerror(WSAGetLastError()));
}
ev->just_checked = 0;
ev->added = 0;
return 0;
}
/** which base gets to handle signals */
static struct event_base* signal_base = NULL;
/** signal handler */
static RETSIGTYPE sigh(int sig)
{
struct event* ev;
if(!signal_base || sig < 0 || sig >= MAX_SIG)
return;
ev = signal_base->signals[sig];
if(!ev)
return;
fptr_ok(fptr_whitelist_event(ev->ev_callback));
(*ev->ev_callback)(sig, EV_SIGNAL, ev->ev_arg);
}
int signal_add(struct event *ev, struct timeval * ATTR_UNUSED(tv))
{
if(ev->ev_fd == -1 || ev->ev_fd >= MAX_SIG)
return -1;
signal_base = ev->ev_base;
ev->ev_base->signals[ev->ev_fd] = ev;
ev->added = 1;
if(signal(ev->ev_fd, sigh) == SIG_ERR) {
return -1;
}
return 0;
}
int signal_del(struct event *ev)
{
if(ev->ev_fd == -1 || ev->ev_fd >= MAX_SIG)
return -1;
ev->ev_base->signals[ev->ev_fd] = NULL;
ev->added = 0;
return 0;
}
void winsock_tcp_wouldblock(struct event* ev, int eventbits)
{
verbose(VERB_ALGO, "winsock: tcp wouldblock %s",
eventbits==EV_READ?"EV_READ":"EV_WRITE");
ev->old_events &= (~eventbits);
if(ev->old_events == 0)
ev->stick_events = 0;
/* in case this is the last sticky event, we could
* possibly run an empty handler loop to reset the base
* tcp_stickies variable
*/
}
int winsock_register_wsaevent(struct event_base* base, struct event* ev,
WSAEVENT wsaevent, void (*cb)(int, short, void*), void* arg)
{
if(base->max == base->cap)
return 0;
memset(ev, 0, sizeof(*ev));
ev->ev_fd = -1;
ev->ev_events = EV_READ;
ev->ev_callback = cb;
ev->ev_arg = arg;
ev->is_signal = 1;
ev->hEvent = wsaevent;
ev->added = 1;
ev->ev_base = base;
ev->idx = ev->ev_base->max++;
ev->ev_base->items[ev->idx] = ev;
return 1;
}
void winsock_unregister_wsaevent(struct event* ev)
{
if(!ev || !ev->added) return;
log_assert(ev->added && ev->ev_base->max > 0)
/* remove item and compact the list */
ev->ev_base->items[ev->idx] = ev->ev_base->items[ev->ev_base->max-1];
ev->ev_base->items[ev->ev_base->max-1] = NULL;
ev->ev_base->max--;
if(ev->idx < ev->ev_base->max)
ev->ev_base->items[ev->idx]->idx = ev->idx;
ev->added = 0;
}
#else /* USE_WINSOCK */
/** symbol so this codefile defines symbols. pleasing ranlib on OSX 10.5 */
int winsock_unused_symbol = 1;
#endif /* USE_WINSOCK */