280 lines
10 KiB
C
280 lines
10 KiB
C
/*
|
|
* util/winsock_event.h - unbound event handling for winsock on windows
|
|
*
|
|
* 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
|
|
*
|
|
* This file contains interface functions with the WinSock2 API on Windows.
|
|
* It uses the winsock WSAWaitForMultipleEvents interface on a number of
|
|
* sockets.
|
|
*
|
|
* Note that windows can only wait for max 64 events at one time.
|
|
*
|
|
* Also, file descriptors cannot be waited for.
|
|
*
|
|
* Named pipes are not easily available (and are not usable in select() ).
|
|
* For interprocess communication, it is possible to wait for a hEvent to
|
|
* be signaled by another thread.
|
|
*
|
|
* When a socket becomes readable, then it will not be flagged as
|
|
* readable again until you have gotten WOULDBLOCK from a recv routine.
|
|
* That means the event handler must store the readability (edge notify)
|
|
* and process the incoming data until it blocks.
|
|
* The function performing recv then has to inform the event handler that
|
|
* the socket has blocked, and the event handler can mark it as such.
|
|
* Thus, this file transforms the edge notify from windows to a level notify
|
|
* that is compatible with UNIX.
|
|
* The WSAEventSelect page says that it does do level notify, as long
|
|
* as you call a recv/write/accept at least once when it is signalled.
|
|
* This last bit is not true, even though documented in server2008 api docs
|
|
* from microsoft, it does not happen at all. Instead you have to test for
|
|
* WSAEWOULDBLOCK on a tcp stream, and only then retest the socket.
|
|
* And before that remember the previous result as still valid.
|
|
*
|
|
* To stay 'fair', instead of emptying a socket completely, the event handler
|
|
* can test the other (marked as blocking) sockets for new events.
|
|
*
|
|
* Additionally, TCP accept sockets get special event support.
|
|
*
|
|
* Socket numbers are not starting small, they can be any number (say 33060).
|
|
* Therefore, bitmaps are not used, but arrays.
|
|
*
|
|
* on winsock, you must use recv() and send() for TCP reads and writes,
|
|
* not read() and write(), those work only on files.
|
|
*
|
|
* Also fseek and fseeko do not work if a FILE is not fopen-ed in binary mode.
|
|
*
|
|
* When under a high load windows gives out lots of errors, from recvfrom
|
|
* on udp sockets for example (WSAECONNRESET). Even though the udp socket
|
|
* has no connection per se.
|
|
*/
|
|
|
|
#ifndef UTIL_WINSOCK_EVENT_H
|
|
#define UTIL_WINSOCK_EVENT_H
|
|
|
|
#ifdef USE_WINSOCK
|
|
|
|
#ifndef HAVE_EVENT_BASE_FREE
|
|
#define HAVE_EVENT_BASE_FREE
|
|
#endif
|
|
|
|
/* redefine the calls to different names so that there is no name
|
|
* collision with other code that uses libevent names. (that uses libunbound)*/
|
|
#define event_init winsockevent_init
|
|
#define event_get_version winsockevent_get_version
|
|
#define event_get_method winsockevent_get_method
|
|
#define event_base_dispatch winsockevent_base_dispatch
|
|
#define event_base_loopexit winsockevent_base_loopexit
|
|
#define event_base_free winsockevent_base_free
|
|
#define event_set winsockevent_set
|
|
#define event_base_set winsockevent_base_set
|
|
#define event_add winsockevent_add
|
|
#define event_del winsockevent_del
|
|
#define signal_add winsocksignal_add
|
|
#define signal_del winsocksignal_del
|
|
|
|
/** event timeout */
|
|
#define EV_TIMEOUT 0x01
|
|
/** event fd readable */
|
|
#define EV_READ 0x02
|
|
/** event fd writable */
|
|
#define EV_WRITE 0x04
|
|
/** event signal */
|
|
#define EV_SIGNAL 0x08
|
|
/** event must persist */
|
|
#define EV_PERSIST 0x10
|
|
|
|
/* needs our redblack tree */
|
|
#include "rbtree.h"
|
|
|
|
/** max number of signals to support */
|
|
#define MAX_SIG 32
|
|
|
|
/** The number of items that the winsock event handler can service.
|
|
* Windows cannot handle more anyway */
|
|
#define WSK_MAX_ITEMS 64
|
|
|
|
/**
|
|
* event base for winsock event handler
|
|
*/
|
|
struct event_base
|
|
{
|
|
/** sorted by timeout (absolute), ptr */
|
|
rbtree_t* times;
|
|
/** array (first part in use) of handles to work on */
|
|
struct event** items;
|
|
/** number of items in use in array */
|
|
int max;
|
|
/** capacity of array, size of array in items */
|
|
int cap;
|
|
/** array of 0 - maxsig of ptr to event for it */
|
|
struct event** signals;
|
|
/** if we need to exit */
|
|
int need_to_exit;
|
|
/** where to store time in seconds */
|
|
time_t* time_secs;
|
|
/** where to store time in microseconds */
|
|
struct timeval* time_tv;
|
|
/**
|
|
* TCP streams have sticky events to them, these are not
|
|
* reported by the windows event system anymore, we have to
|
|
* keep reporting those events as present until wouldblock() is
|
|
* signalled by the handler back to use.
|
|
*/
|
|
int tcp_stickies;
|
|
/**
|
|
* should next cycle process reinvigorated stickies,
|
|
* these are stickies that have been stored, but due to a new
|
|
* event_add a sudden interest in the event has incepted.
|
|
*/
|
|
int tcp_reinvigorated;
|
|
/** The list of events that is currently being processed. */
|
|
WSAEVENT waitfor[WSK_MAX_ITEMS];
|
|
};
|
|
|
|
/**
|
|
* Event structure. Has some of the event elements.
|
|
*/
|
|
struct event {
|
|
/** node in timeout rbtree */
|
|
rbnode_t node;
|
|
/** is event already added */
|
|
int added;
|
|
|
|
/** event base it belongs to */
|
|
struct event_base *ev_base;
|
|
/** fd to poll or -1 for timeouts. signal number for sigs. */
|
|
int ev_fd;
|
|
/** what events this event is interested in, see EV_.. above. */
|
|
short ev_events;
|
|
/** timeout value */
|
|
struct timeval ev_timeout;
|
|
|
|
/** callback to call: fd, eventbits, userarg */
|
|
void (*ev_callback)(int, short, void *);
|
|
/** callback user arg */
|
|
void *ev_arg;
|
|
|
|
/* ----- nonpublic part, for winsock_event only ----- */
|
|
/** index of this event in the items array (if added) */
|
|
int idx;
|
|
/** the event handle to wait for new events to become ready */
|
|
WSAEVENT hEvent;
|
|
/** true if this filedes is a TCP socket and needs special attention */
|
|
int is_tcp;
|
|
/** remembered EV_ values */
|
|
short old_events;
|
|
/** should remembered EV_ values be used for TCP streams.
|
|
* Reset after WOULDBLOCK is signaled using the function. */
|
|
int stick_events;
|
|
|
|
/** true if this event is a signaling WSAEvent by the user.
|
|
* User created and user closed WSAEvent. Only signaled/unsigneled,
|
|
* no read/write/distinctions needed. */
|
|
int is_signal;
|
|
/** used during callbacks to see which events were just checked */
|
|
int just_checked;
|
|
};
|
|
|
|
/** create event base */
|
|
void *event_init(time_t* time_secs, struct timeval* time_tv);
|
|
/** get version */
|
|
const char *event_get_version(void);
|
|
/** get polling method (select,epoll) */
|
|
const char *event_get_method(void);
|
|
/** run select in a loop */
|
|
int event_base_dispatch(struct event_base *);
|
|
/** exit that loop */
|
|
int event_base_loopexit(struct event_base *, struct timeval *);
|
|
/** free event base. Free events yourself */
|
|
void event_base_free(struct event_base *);
|
|
/** set content of event */
|
|
void event_set(struct event *, int, short, void (*)(int, short, void *), void *);
|
|
|
|
/** add event to a base. You *must* call this for every event. */
|
|
int event_base_set(struct event_base *, struct event *);
|
|
/** add event to make it active. You may not change it with event_set anymore */
|
|
int event_add(struct event *, struct timeval *);
|
|
/** remove event. You may change it again */
|
|
int event_del(struct event *);
|
|
|
|
#define evtimer_add(ev, tv) event_add(ev, tv)
|
|
#define evtimer_del(ev) event_del(ev)
|
|
|
|
/* uses different implementation. Cannot mix fd/timeouts and signals inside
|
|
* the same struct event. create several event structs for that. */
|
|
/** install signal handler */
|
|
int signal_add(struct event *, struct timeval *);
|
|
/** set signal event contents */
|
|
#define signal_set(ev, x, cb, arg) \
|
|
event_set(ev, x, EV_SIGNAL|EV_PERSIST, cb, arg)
|
|
/** remove signal handler */
|
|
int signal_del(struct event *);
|
|
|
|
/** compare events in tree, based on timevalue, ptr for uniqueness */
|
|
int mini_ev_cmp(const void* a, const void* b);
|
|
|
|
/**
|
|
* Routine for windows only, where the handling layer can signal that
|
|
* a TCP stream encountered WSAEWOULDBLOCK for a stream and thus needs
|
|
* retesting the event.
|
|
* Pass if EV_READ or EV_WRITE gave wouldblock.
|
|
*/
|
|
void winsock_tcp_wouldblock(struct event* ev, int eventbit);
|
|
|
|
/**
|
|
* Routine for windows only. where you pass a signal WSAEvent that
|
|
* you wait for. When the event is signaled, the callback gets called.
|
|
* The callback has to WSAResetEvent to disable the signal.
|
|
* @param base: the event base.
|
|
* @param ev: the event structure for data storage
|
|
* can be passed uninitialised.
|
|
* @param wsaevent: the WSAEvent that gets signaled.
|
|
* @param cb: callback routine.
|
|
* @param arg: user argument to callback routine.
|
|
* @return false on error.
|
|
*/
|
|
int winsock_register_wsaevent(struct event_base* base, struct event* ev,
|
|
WSAEVENT wsaevent, void (*cb)(int, short, void*), void* arg);
|
|
|
|
/**
|
|
* Unregister a wsaevent. User has to close the WSAEVENT itself.
|
|
* @param ev: event data storage.
|
|
*/
|
|
void winsock_unregister_wsaevent(struct event* ev);
|
|
|
|
#endif /* USE_WINSOCK */
|
|
#endif /* UTIL_WINSOCK_EVENT_H */
|