[redis.git] / ae.c

/* A simple event-driven programming library. Originally I wrote this code
 * for the Jim's event-loop (Jim is a Tcl interpreter) but later translated
 * it in form of a library for easy reuse.
 *
 * Copyright (c) 2006-2009, Salvatore Sanfilippo <antirez at gmail dot com>
 * All rights reserved.
 *
 * 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 Redis 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 OWNER 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.
 */

#include <stdio.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>

#include "ae.h"
#include "zmalloc.h"
#include "config.h"

/* Include the best multiplexing layer supported by this system.
 * The following should be ordered by performances, descending. */
#ifdef HAVE_EPOLL
#include "ae_epoll.c"
#else
#include "ae_select.c"
#endif

aeEventLoop *aeCreateEventLoop(void) {
    aeEventLoop *eventLoop;
    int i;

    eventLoop = zmalloc(sizeof(*eventLoop));
    if (!eventLoop) return NULL;
    eventLoop->timeEventHead = NULL;
    eventLoop->timeEventNextId = 0;
    eventLoop->stop = 0;
    eventLoop->maxfd = -1;
    if (aeApiCreate(eventLoop) == -1) {
        zfree(eventLoop);
        return NULL;
    }
    /* Events with mask == AE_NONE are not set. So let's initialize the
     * vector with it. */
    for (i = 0; i < AE_SETSIZE; i++)
        eventLoop->events[i].mask = AE_NONE;
    return eventLoop;
}

void aeDeleteEventLoop(aeEventLoop *eventLoop) {
    aeApiFree(eventLoop);
    zfree(eventLoop);
}

void aeStop(aeEventLoop *eventLoop) {
    eventLoop->stop = 1;
}

int aeCreateFileEvent(aeEventLoop *eventLoop, int fd, int mask,
        aeFileProc *proc, void *clientData)
{
    if (fd >= AE_SETSIZE) return AE_ERR;
    aeFileEvent *fe = &eventLoop->events[fd];

    if (aeApiAddEvent(eventLoop, fd, mask) == -1)
        return AE_ERR;
    fe->mask |= mask;
    if (mask & AE_READABLE) fe->rfileProc = proc;
    if (mask & AE_WRITABLE) fe->wfileProc = proc;
    if (mask & AE_EXCEPTION) fe->efileProc = proc;
    fe->clientData = clientData;
    if (fd > eventLoop->maxfd)
        eventLoop->maxfd = fd;
    return AE_OK;
}

void aeDeleteFileEvent(aeEventLoop *eventLoop, int fd, int mask)
{
    if (fd >= AE_SETSIZE) return;
    aeFileEvent *fe = &eventLoop->events[fd];

    if (fe->mask == AE_NONE) return;
    fe->mask = fe->mask & (~mask);
    if (fd == eventLoop->maxfd && fe->mask == AE_NONE) {
        /* Update the max fd */
        int j;

        for (j = eventLoop->maxfd-1; j >= 0; j--)
            if (eventLoop->events[j].mask != AE_NONE) break;
        eventLoop->maxfd = j;
    }
    aeApiDelEvent(eventLoop, fd, mask);
}

static void aeGetTime(long *seconds, long *milliseconds)
{
    struct timeval tv;

    gettimeofday(&tv, NULL);
    *seconds = tv.tv_sec;
    *milliseconds = tv.tv_usec/1000;
}

static void aeAddMillisecondsToNow(long long milliseconds, long *sec, long *ms) {
    long cur_sec, cur_ms, when_sec, when_ms;

    aeGetTime(&cur_sec, &cur_ms);
    when_sec = cur_sec + milliseconds/1000;
    when_ms = cur_ms + milliseconds%1000;
    if (when_ms >= 1000) {
        when_sec ++;
        when_ms -= 1000;
    }
    *sec = when_sec;
    *ms = when_ms;
}

long long aeCreateTimeEvent(aeEventLoop *eventLoop, long long milliseconds,
        aeTimeProc *proc, void *clientData,
        aeEventFinalizerProc *finalizerProc)
{
    long long id = eventLoop->timeEventNextId++;
    aeTimeEvent *te;

    te = zmalloc(sizeof(*te));
    if (te == NULL) return AE_ERR;
    te->id = id;
    aeAddMillisecondsToNow(milliseconds,&te->when_sec,&te->when_ms);
    te->timeProc = proc;
    te->finalizerProc = finalizerProc;
    te->clientData = clientData;
    te->next = eventLoop->timeEventHead;
    eventLoop->timeEventHead = te;
    return id;
}

int aeDeleteTimeEvent(aeEventLoop *eventLoop, long long id)
{
    aeTimeEvent *te, *prev = NULL;

    te = eventLoop->timeEventHead;
    while(te) {
        if (te->id == id) {
            if (prev == NULL)
                eventLoop->timeEventHead = te->next;
            else
                prev->next = te->next;
            if (te->finalizerProc)
                te->finalizerProc(eventLoop, te->clientData);
            zfree(te);
            return AE_OK;
        }
        prev = te;
        te = te->next;
    }
    return AE_ERR; /* NO event with the specified ID found */
}

/* Search the first timer to fire.
 * This operation is useful to know how many time the select can be
 * put in sleep without to delay any event.
 * If there are no timers NULL is returned.
 *
 * Note that's O(N) since time events are unsorted.
 * Possible optimizations (not needed by Redis so far, but...):
 * 1) Insert the event in order, so that the nearest is just the head.
 *    Much better but still insertion or deletion of timers is O(N).
 * 2) Use a skiplist to have this operation as O(1) and insertion as O(log(N)).
 */
static aeTimeEvent *aeSearchNearestTimer(aeEventLoop *eventLoop)
{
    aeTimeEvent *te = eventLoop->timeEventHead;
    aeTimeEvent *nearest = NULL;

    while(te) {
        if (!nearest || te->when_sec < nearest->when_sec ||
                (te->when_sec == nearest->when_sec &&
                 te->when_ms < nearest->when_ms))
            nearest = te;
        te = te->next;
    }
    return nearest;
}

/* Process time events */
static int processTimeEvents(aeEventLoop *eventLoop) {
    int processed = 0;
    aeTimeEvent *te;
    long long maxId;

    te = eventLoop->timeEventHead;
    maxId = eventLoop->timeEventNextId-1;
    while(te) {
        long now_sec, now_ms;
        long long id;

        if (te->id > maxId) {
            te = te->next;
            continue;
        }
        aeGetTime(&now_sec, &now_ms);
        if (now_sec > te->when_sec ||
            (now_sec == te->when_sec && now_ms >= te->when_ms))
        {
            int retval;

            id = te->id;
            retval = te->timeProc(eventLoop, id, te->clientData);
            processed++;
            /* After an event is processed our time event list may
             * no longer be the same, so we restart from head.
             * Still we make sure to don't process events registered
             * by event handlers itself in order to don't loop forever.
             * To do so we saved the max ID we want to handle.
             *
             * FUTURE OPTIMIZATIONS:
             * Note that this is NOT great algorithmically. Redis uses
             * a single time event so it's not a problem but the right
             * way to do this is to add the new elements on head, and
             * to flag deleted elements in a special way for later
             * deletion (putting references to the nodes to delete into
             * another linked list). */
            if (retval != AE_NOMORE) {
                aeAddMillisecondsToNow(retval,&te->when_sec,&te->when_ms);
            } else {
                aeDeleteTimeEvent(eventLoop, id);
            }
            te = eventLoop->timeEventHead;
        } else {
            te = te->next;
        }
    }
    return processed;
}

/* Process every pending time event, then every pending file event
 * (that may be registered by time event callbacks just processed).
 * Without special flags the function sleeps until some file event
 * fires, or when the next time event occurrs (if any).
 *
 * If flags is 0, the function does nothing and returns.
 * if flags has AE_ALL_EVENTS set, all the kind of events are processed.
 * if flags has AE_FILE_EVENTS set, file events are processed.
 * if flags has AE_TIME_EVENTS set, time events are processed.
 * if flags has AE_DONT_WAIT set the function returns ASAP until all
 * the events that's possible to process without to wait are processed.
 *
 * The function returns the number of events processed. */
int aeProcessEvents(aeEventLoop *eventLoop, int flags)
{
    int processed = 0, numevents;

    /* Nothing to do? return ASAP */
    if (!(flags & AE_TIME_EVENTS) && !(flags & AE_FILE_EVENTS)) return 0;

    /* Note that we want call select() even if there are no
     * file events to process as long as we want to process time
     * events, in order to sleep until the next time event is ready
     * to fire. */
    if (eventLoop->maxfd != -1 ||
        ((flags & AE_TIME_EVENTS) && !(flags & AE_DONT_WAIT))) {
        int j;
        aeTimeEvent *shortest = NULL;
        struct timeval tv, *tvp;

        if (flags & AE_TIME_EVENTS && !(flags & AE_DONT_WAIT))
            shortest = aeSearchNearestTimer(eventLoop);
        if (shortest) {
            long now_sec, now_ms;

            /* Calculate the time missing for the nearest
             * timer to fire. */
            aeGetTime(&now_sec, &now_ms);
            tvp = &tv;
            tvp->tv_sec = shortest->when_sec - now_sec;
            if (shortest->when_ms < now_ms) {
                tvp->tv_usec = ((shortest->when_ms+1000) - now_ms)*1000;
                tvp->tv_sec --;
            } else {
                tvp->tv_usec = (shortest->when_ms - now_ms)*1000;
            }
            if (tvp->tv_sec < 0) tvp->tv_sec = 0;
            if (tvp->tv_usec < 0) tvp->tv_usec = 0;
        } else {
            /* If we have to check for events but need to return
             * ASAP because of AE_DONT_WAIT we need to se the timeout
             * to zero */
            if (flags & AE_DONT_WAIT) {
                tv.tv_sec = tv.tv_usec = 0;
                tvp = &tv;
            } else {
                /* Otherwise we can block */
                tvp = NULL; /* wait forever */
            }
        }

        numevents = aeApiPoll(eventLoop, tvp);
        for (j = 0; j < numevents; j++) {
            aeFileEvent *fe = &eventLoop->events[eventLoop->fired[j].fd];
            int mask = eventLoop->fired[j].mask;
            int fd = eventLoop->fired[j].fd;

	    /* note the fe->mask & mask & ... code: maybe an already processed
             * event removed an element that fired and we still didn't
             * processed, so we check if the event is still valid. */
            if (fe->mask & mask & AE_READABLE)
                fe->rfileProc(eventLoop,fd,fe->clientData,mask);
            if (fe->mask & mask & AE_WRITABLE && fe->wfileProc != fe->rfileProc)
                fe->wfileProc(eventLoop,fd,fe->clientData,mask);
            if (fe->mask & mask & AE_EXCEPTION &&
				       fe->efileProc != fe->wfileProc &&
                                       fe->efileProc != fe->rfileProc)
                fe->efileProc(eventLoop,fd,fe->clientData,mask);
            processed++;
        }
    }
    /* Check time events */
    if (flags & AE_TIME_EVENTS)
        processed += processTimeEvents(eventLoop);

    return processed; /* return the number of processed file/time events */
}

/* Wait for millseconds until the given file descriptor becomes
 * writable/readable/exception */
int aeWait(int fd, int mask, long long milliseconds) {
    struct timeval tv;
    fd_set rfds, wfds, efds;
    int retmask = 0, retval;

    tv.tv_sec = milliseconds/1000;
    tv.tv_usec = (milliseconds%1000)*1000;
    FD_ZERO(&rfds);
    FD_ZERO(&wfds);
    FD_ZERO(&efds);

    if (mask & AE_READABLE) FD_SET(fd,&rfds);
    if (mask & AE_WRITABLE) FD_SET(fd,&wfds);
    if (mask & AE_EXCEPTION) FD_SET(fd,&efds);
    if ((retval = select(fd+1, &rfds, &wfds, &efds, &tv)) > 0) {
        if (FD_ISSET(fd,&rfds)) retmask |= AE_READABLE;
        if (FD_ISSET(fd,&wfds)) retmask |= AE_WRITABLE;
        if (FD_ISSET(fd,&efds)) retmask |= AE_EXCEPTION;
        return retmask;
    } else {
        return retval;
    }
}

void aeMain(aeEventLoop *eventLoop)
{
    eventLoop->stop = 0;
    while (!eventLoop->stop)
        aeProcessEvents(eventLoop, AE_ALL_EVENTS);
}
Commit	Line	Data
ed9b544e	1	/* A simple event-driven programming library. Originally I wrote this code
	2	* for the Jim's event-loop (Jim is a Tcl interpreter) but later translated
	3	* it in form of a library for easy reuse.
	4	*
	5	* Copyright (c) 2006-2009, Salvatore Sanfilippo <antirez at gmail dot com>
	6	* All rights reserved.
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions are met:
	10	*
	11	* * Redistributions of source code must retain the above copyright notice,
	12	* this list of conditions and the following disclaimer.
	13	* * Redistributions in binary form must reproduce the above copyright
	14	* notice, this list of conditions and the following disclaimer in the
	15	* documentation and/or other materials provided with the distribution.
	16	* * Neither the name of Redis nor the names of its contributors may be used
	17	* to endorse or promote products derived from this software without
	18	* specific prior written permission.
	19	*
	20	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	21	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	24	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	25	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	26	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	27	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	28	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	29	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	30	* POSSIBILITY OF SUCH DAMAGE.
	31	*/
	32
	33	#include <stdio.h>
	34	#include <sys/time.h>
	35	#include <sys/types.h>
	36	#include <unistd.h>
	37	#include <stdlib.h>
	38
	39	#include "ae.h"
	40	#include "zmalloc.h"
266373b2	41	#include "config.h"
	42
	43	/* Include the best multiplexing layer supported by this system.
	44	* The following should be ordered by performances, descending. */
	45	#ifdef HAVE_EPOLL
	46	#include "ae_epoll.c"
	47	#else
	48	#include "ae_select.c"
	49	#endif
ed9b544e	50
	51	aeEventLoop *aeCreateEventLoop(void) {
	52	aeEventLoop *eventLoop;
266373b2	53	int i;
ed9b544e	54
	55	eventLoop = zmalloc(sizeof(*eventLoop));
	56	if (!eventLoop) return NULL;
ed9b544e	57	eventLoop->timeEventHead = NULL;
	58	eventLoop->timeEventNextId = 0;
	59	eventLoop->stop = 0;
266373b2	60	eventLoop->maxfd = -1;
	61	if (aeApiCreate(eventLoop) == -1) {
	62	zfree(eventLoop);
	63	return NULL;
	64	}
	65	/* Events with mask == AE_NONE are not set. So let's initialize the
	66	* vector with it. */
	67	for (i = 0; i < AE_SETSIZE; i++)
	68	eventLoop->events[i].mask = AE_NONE;
ed9b544e	69	return eventLoop;
	70	}
	71
	72	void aeDeleteEventLoop(aeEventLoop *eventLoop) {
266373b2	73	aeApiFree(eventLoop);
ed9b544e	74	zfree(eventLoop);
	75	}
	76
	77	void aeStop(aeEventLoop *eventLoop) {
	78	eventLoop->stop = 1;
	79	}
	80
	81	int aeCreateFileEvent(aeEventLoop *eventLoop, int fd, int mask,
266373b2	82	aeFileProc proc, void clientData)
ed9b544e	83	{
266373b2	84	if (fd >= AE_SETSIZE) return AE_ERR;
	85	aeFileEvent *fe = &eventLoop->events[fd];
	86
	87	if (aeApiAddEvent(eventLoop, fd, mask) == -1)
	88	return AE_ERR;
	89	fe->mask \|= mask;
	90	if (mask & AE_READABLE) fe->rfileProc = proc;
	91	if (mask & AE_WRITABLE) fe->wfileProc = proc;
	92	if (mask & AE_EXCEPTION) fe->efileProc = proc;
ed9b544e	93	fe->clientData = clientData;
266373b2	94	if (fd > eventLoop->maxfd)
266373b2	95	eventLoop->maxfd = fd;
ed9b544e	96	return AE_OK;
	97	}
	98
	99	void aeDeleteFileEvent(aeEventLoop *eventLoop, int fd, int mask)
	100	{
266373b2	101	if (fd >= AE_SETSIZE) return;
	102	aeFileEvent *fe = &eventLoop->events[fd];
	103
	104	if (fe->mask == AE_NONE) return;
	105	fe->mask = fe->mask & (~mask);
	106	if (fd == eventLoop->maxfd && fe->mask == AE_NONE) {
	107	/* Update the max fd */
	108	int j;
	109
	110	for (j = eventLoop->maxfd-1; j >= 0; j--)
	111	if (eventLoop->events[j].mask != AE_NONE) break;
	112	eventLoop->maxfd = j;
ed9b544e	113	}
266373b2	114	aeApiDelEvent(eventLoop, fd, mask);
ed9b544e	115	}
	116
	117	static void aeGetTime(long seconds, long milliseconds)
	118	{
	119	struct timeval tv;
	120
	121	gettimeofday(&tv, NULL);
	122	*seconds = tv.tv_sec;
	123	*milliseconds = tv.tv_usec/1000;
	124	}
	125
	126	static void aeAddMillisecondsToNow(long long milliseconds, long sec, long ms) {
	127	long cur_sec, cur_ms, when_sec, when_ms;
	128
	129	aeGetTime(&cur_sec, &cur_ms);
	130	when_sec = cur_sec + milliseconds/1000;
	131	when_ms = cur_ms + milliseconds%1000;
	132	if (when_ms >= 1000) {
	133	when_sec ++;
	134	when_ms -= 1000;
	135	}
	136	*sec = when_sec;
	137	*ms = when_ms;
	138	}
	139
	140	long long aeCreateTimeEvent(aeEventLoop *eventLoop, long long milliseconds,
	141	aeTimeProc proc, void clientData,
	142	aeEventFinalizerProc *finalizerProc)
	143	{
	144	long long id = eventLoop->timeEventNextId++;
	145	aeTimeEvent *te;
	146
	147	te = zmalloc(sizeof(*te));
	148	if (te == NULL) return AE_ERR;
	149	te->id = id;
	150	aeAddMillisecondsToNow(milliseconds,&te->when_sec,&te->when_ms);
	151	te->timeProc = proc;
	152	te->finalizerProc = finalizerProc;
	153	te->clientData = clientData;
	154	te->next = eventLoop->timeEventHead;
	155	eventLoop->timeEventHead = te;
	156	return id;
	157	}
	158
	159	int aeDeleteTimeEvent(aeEventLoop *eventLoop, long long id)
	160	{
	161	aeTimeEvent te, prev = NULL;
	162
	163	te = eventLoop->timeEventHead;
	164	while(te) {
	165	if (te->id == id) {
	166	if (prev == NULL)
	167	eventLoop->timeEventHead = te->next;
	168	else
	169	prev->next = te->next;
	170	if (te->finalizerProc)
	171	te->finalizerProc(eventLoop, te->clientData);
	172	zfree(te);
	173	return AE_OK;
	174	}
	175	prev = te;
	176	te = te->next;
	177	}
	178	return AE_ERR; /* NO event with the specified ID found */
179	}
180
181	/* Search the first timer to fire.
182	* This operation is useful to know how many time the select can be
183	* put in sleep without to delay any event.
184	* If there are no timers NULL is returned.
185	*
5b2a1c29	186	* Note that's O(N) since time events are unsorted.
	187	* Possible optimizations (not needed by Redis so far, but...):
	188	* 1) Insert the event in order, so that the nearest is just the head.
	189	* Much better but still insertion or deletion of timers is O(N).
	190	* 2) Use a skiplist to have this operation as O(1) and insertion as O(log(N)).
	191	*/
ed9b544e	192	static aeTimeEvent aeSearchNearestTimer(aeEventLoop eventLoop)
	193	{
	194	aeTimeEvent *te = eventLoop->timeEventHead;
	195	aeTimeEvent *nearest = NULL;
	196
	197	while(te) {
	198	if (!nearest \|\| te->when_sec < nearest->when_sec \|\|
	199	(te->when_sec == nearest->when_sec &&
	200	te->when_ms < nearest->when_ms))
	201	nearest = te;
	202	te = te->next;
	203	}
	204	return nearest;
	205	}
	206
5b2a1c29	207	/* Process time events */
	208	static int processTimeEvents(aeEventLoop *eventLoop) {
	209	int processed = 0;
	210	aeTimeEvent *te;
	211	long long maxId;
	212
	213	te = eventLoop->timeEventHead;
	214	maxId = eventLoop->timeEventNextId-1;
	215	while(te) {
	216	long now_sec, now_ms;
	217	long long id;
	218
	219	if (te->id > maxId) {
	220	te = te->next;
	221	continue;
	222	}
	223	aeGetTime(&now_sec, &now_ms);
	224	if (now_sec > te->when_sec \|\|
	225	(now_sec == te->when_sec && now_ms >= te->when_ms))
	226	{
	227	int retval;
	228
	229	id = te->id;
	230	retval = te->timeProc(eventLoop, id, te->clientData);
	231	processed++;
	232	/* After an event is processed our time event list may
	233	* no longer be the same, so we restart from head.
	234	* Still we make sure to don't process events registered
	235	* by event handlers itself in order to don't loop forever.
	236	* To do so we saved the max ID we want to handle.
	237	*
	238	* FUTURE OPTIMIZATIONS:
	239	* Note that this is NOT great algorithmically. Redis uses
	240	* a single time event so it's not a problem but the right
	241	* way to do this is to add the new elements on head, and
	242	* to flag deleted elements in a special way for later
	243	* deletion (putting references to the nodes to delete into
	244	* another linked list). */
	245	if (retval != AE_NOMORE) {
	246	aeAddMillisecondsToNow(retval,&te->when_sec,&te->when_ms);
	247	} else {
	248	aeDeleteTimeEvent(eventLoop, id);
	249	}
	250	te = eventLoop->timeEventHead;
	251	} else {
	252	te = te->next;
	253	}
	254	}
	255	return processed;
	256	}
	257
ed9b544e	258	/* Process every pending time event, then every pending file event
	259	* (that may be registered by time event callbacks just processed).
	260	* Without special flags the function sleeps until some file event
	261	* fires, or when the next time event occurrs (if any).
	262	*
	263	* If flags is 0, the function does nothing and returns.
	264	* if flags has AE_ALL_EVENTS set, all the kind of events are processed.
	265	* if flags has AE_FILE_EVENTS set, file events are processed.
	266	* if flags has AE_TIME_EVENTS set, time events are processed.
	267	* if flags has AE_DONT_WAIT set the function returns ASAP until all
	268	* the events that's possible to process without to wait are processed.
	269	*
	270	* The function returns the number of events processed. */
	271	int aeProcessEvents(aeEventLoop *eventLoop, int flags)
	272	{
266373b2	273	int processed = 0, numevents;
ed9b544e	274
	275	/* Nothing to do? return ASAP */
	276	if (!(flags & AE_TIME_EVENTS) && !(flags & AE_FILE_EVENTS)) return 0;
	277
ed9b544e	278	/* Note that we want call select() even if there are no
	279	* file events to process as long as we want to process time
	280	* events, in order to sleep until the next time event is ready
	281	* to fire. */
266373b2	282	if (eventLoop->maxfd != -1 \|\|
	283	((flags & AE_TIME_EVENTS) && !(flags & AE_DONT_WAIT))) {
	284	int j;
ed9b544e	285	aeTimeEvent *shortest = NULL;
	286	struct timeval tv, *tvp;
	287
	288	if (flags & AE_TIME_EVENTS && !(flags & AE_DONT_WAIT))
	289	shortest = aeSearchNearestTimer(eventLoop);
	290	if (shortest) {
	291	long now_sec, now_ms;
	292
	293	/* Calculate the time missing for the nearest
	294	* timer to fire. */
	295	aeGetTime(&now_sec, &now_ms);
	296	tvp = &tv;
	297	tvp->tv_sec = shortest->when_sec - now_sec;
	298	if (shortest->when_ms < now_ms) {
	299	tvp->tv_usec = ((shortest->when_ms+1000) - now_ms)*1000;
	300	tvp->tv_sec --;
	301	} else {
	302	tvp->tv_usec = (shortest->when_ms - now_ms)*1000;
	303	}
266373b2	304	if (tvp->tv_sec < 0) tvp->tv_sec = 0;
266373b2	305	if (tvp->tv_usec < 0) tvp->tv_usec = 0;
ed9b544e	306	} else {
	307	/* If we have to check for events but need to return
	308	* ASAP because of AE_DONT_WAIT we need to se the timeout
	309	* to zero */
	310	if (flags & AE_DONT_WAIT) {
	311	tv.tv_sec = tv.tv_usec = 0;
	312	tvp = &tv;
	313	} else {
	314	/* Otherwise we can block */
	315	tvp = NULL; /* wait forever */
	316	}
	317	}
	318
266373b2	319	numevents = aeApiPoll(eventLoop, tvp);
	320	for (j = 0; j < numevents; j++) {
	321	aeFileEvent *fe = &eventLoop->events[eventLoop->fired[j].fd];
	322	int mask = eventLoop->fired[j].mask;
	323	int fd = eventLoop->fired[j].fd;
	324
	325	/* note the fe->mask & mask & ... code: maybe an already processed
	326	* event removed an element that fired and we still didn't
	327	* processed, so we check if the event is still valid. */
	328	if (fe->mask & mask & AE_READABLE)
	329	fe->rfileProc(eventLoop,fd,fe->clientData,mask);
	330	if (fe->mask & mask & AE_WRITABLE && fe->wfileProc != fe->rfileProc)
	331	fe->wfileProc(eventLoop,fd,fe->clientData,mask);
	332	if (fe->mask & mask & AE_EXCEPTION &&
	333	fe->efileProc != fe->wfileProc &&
	334	fe->efileProc != fe->rfileProc)
	335	fe->efileProc(eventLoop,fd,fe->clientData,mask);
	336	processed++;
ed9b544e	337	}
	338	}
	339	/* Check time events */
5b2a1c29	340	if (flags & AE_TIME_EVENTS)
5b2a1c29	341	processed += processTimeEvents(eventLoop);
ed9b544e	342
ed9b544e	343	return processed; /* return the number of processed file/time events */
	344	}
	345
	346	/* Wait for millseconds until the given file descriptor becomes
	347	* writable/readable/exception */
	348	int aeWait(int fd, int mask, long long milliseconds) {
	349	struct timeval tv;
	350	fd_set rfds, wfds, efds;
	351	int retmask = 0, retval;
	352
	353	tv.tv_sec = milliseconds/1000;
	354	tv.tv_usec = (milliseconds%1000)*1000;
	355	FD_ZERO(&rfds);
	356	FD_ZERO(&wfds);
	357	FD_ZERO(&efds);
	358
	359	if (mask & AE_READABLE) FD_SET(fd,&rfds);
	360	if (mask & AE_WRITABLE) FD_SET(fd,&wfds);
	361	if (mask & AE_EXCEPTION) FD_SET(fd,&efds);
	362	if ((retval = select(fd+1, &rfds, &wfds, &efds, &tv)) > 0) {
	363	if (FD_ISSET(fd,&rfds)) retmask \|= AE_READABLE;
	364	if (FD_ISSET(fd,&wfds)) retmask \|= AE_WRITABLE;
	365	if (FD_ISSET(fd,&efds)) retmask \|= AE_EXCEPTION;
	366	return retmask;
	367	} else {
	368	return retval;
	369	}
	370	}
	371
	372	void aeMain(aeEventLoop *eventLoop)
	373	{
	374	eventLoop->stop = 0;
	375	while (!eventLoop->stop)
	376	aeProcessEvents(eventLoop, AE_ALL_EVENTS);
	377	}