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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 13:40:54 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 13:40:54 +0000
commit317c0644ccf108aa23ef3fd8358bd66c2840bfc0 (patch)
treec417b3d25c86b775989cb5ac042f37611b626c8a /src/ae.c
parentInitial commit. (diff)
downloadredis-317c0644ccf108aa23ef3fd8358bd66c2840bfc0.tar.xz
redis-317c0644ccf108aa23ef3fd8358bd66c2840bfc0.zip
Adding upstream version 5:7.2.4.upstream/5%7.2.4
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/ae.c')
-rw-r--r--src/ae.c512
1 files changed, 512 insertions, 0 deletions
diff --git a/src/ae.c b/src/ae.c
new file mode 100644
index 0000000..ff60630
--- /dev/null
+++ b/src/ae.c
@@ -0,0 +1,512 @@
+/* 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) 2006-2010, 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 "ae.h"
+#include "anet.h"
+#include "redisassert.h"
+
+#include <stdio.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <poll.h>
+#include <string.h>
+#include <time.h>
+#include <errno.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_EVPORT
+#include "ae_evport.c"
+#else
+ #ifdef HAVE_EPOLL
+ #include "ae_epoll.c"
+ #else
+ #ifdef HAVE_KQUEUE
+ #include "ae_kqueue.c"
+ #else
+ #include "ae_select.c"
+ #endif
+ #endif
+#endif
+
+
+aeEventLoop *aeCreateEventLoop(int setsize) {
+ aeEventLoop *eventLoop;
+ int i;
+
+ monotonicInit(); /* just in case the calling app didn't initialize */
+
+ if ((eventLoop = zmalloc(sizeof(*eventLoop))) == NULL) goto err;
+ eventLoop->events = zmalloc(sizeof(aeFileEvent)*setsize);
+ eventLoop->fired = zmalloc(sizeof(aeFiredEvent)*setsize);
+ if (eventLoop->events == NULL || eventLoop->fired == NULL) goto err;
+ eventLoop->setsize = setsize;
+ eventLoop->timeEventHead = NULL;
+ eventLoop->timeEventNextId = 0;
+ eventLoop->stop = 0;
+ eventLoop->maxfd = -1;
+ eventLoop->beforesleep = NULL;
+ eventLoop->aftersleep = NULL;
+ eventLoop->flags = 0;
+ if (aeApiCreate(eventLoop) == -1) goto err;
+ /* Events with mask == AE_NONE are not set. So let's initialize the
+ * vector with it. */
+ for (i = 0; i < setsize; i++)
+ eventLoop->events[i].mask = AE_NONE;
+ return eventLoop;
+
+err:
+ if (eventLoop) {
+ zfree(eventLoop->events);
+ zfree(eventLoop->fired);
+ zfree(eventLoop);
+ }
+ return NULL;
+}
+
+/* Return the current set size. */
+int aeGetSetSize(aeEventLoop *eventLoop) {
+ return eventLoop->setsize;
+}
+
+/*
+ * Tell the event processing to change the wait timeout as soon as possible.
+ *
+ * Note: it just means you turn on/off the global AE_DONT_WAIT.
+ */
+void aeSetDontWait(aeEventLoop *eventLoop, int noWait) {
+ if (noWait)
+ eventLoop->flags |= AE_DONT_WAIT;
+ else
+ eventLoop->flags &= ~AE_DONT_WAIT;
+}
+
+/* Resize the maximum set size of the event loop.
+ * If the requested set size is smaller than the current set size, but
+ * there is already a file descriptor in use that is >= the requested
+ * set size minus one, AE_ERR is returned and the operation is not
+ * performed at all.
+ *
+ * Otherwise AE_OK is returned and the operation is successful. */
+int aeResizeSetSize(aeEventLoop *eventLoop, int setsize) {
+ int i;
+
+ if (setsize == eventLoop->setsize) return AE_OK;
+ if (eventLoop->maxfd >= setsize) return AE_ERR;
+ if (aeApiResize(eventLoop,setsize) == -1) return AE_ERR;
+
+ eventLoop->events = zrealloc(eventLoop->events,sizeof(aeFileEvent)*setsize);
+ eventLoop->fired = zrealloc(eventLoop->fired,sizeof(aeFiredEvent)*setsize);
+ eventLoop->setsize = setsize;
+
+ /* Make sure that if we created new slots, they are initialized with
+ * an AE_NONE mask. */
+ for (i = eventLoop->maxfd+1; i < setsize; i++)
+ eventLoop->events[i].mask = AE_NONE;
+ return AE_OK;
+}
+
+void aeDeleteEventLoop(aeEventLoop *eventLoop) {
+ aeApiFree(eventLoop);
+ zfree(eventLoop->events);
+ zfree(eventLoop->fired);
+
+ /* Free the time events list. */
+ aeTimeEvent *next_te, *te = eventLoop->timeEventHead;
+ while (te) {
+ next_te = te->next;
+ zfree(te);
+ te = next_te;
+ }
+ zfree(eventLoop);
+}
+
+void aeStop(aeEventLoop *eventLoop) {
+ eventLoop->stop = 1;
+}
+
+int aeCreateFileEvent(aeEventLoop *eventLoop, int fd, int mask,
+ aeFileProc *proc, void *clientData)
+{
+ if (fd >= eventLoop->setsize) {
+ errno = ERANGE;
+ 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;
+ fe->clientData = clientData;
+ if (fd > eventLoop->maxfd)
+ eventLoop->maxfd = fd;
+ return AE_OK;
+}
+
+void aeDeleteFileEvent(aeEventLoop *eventLoop, int fd, int mask)
+{
+ if (fd >= eventLoop->setsize) return;
+ aeFileEvent *fe = &eventLoop->events[fd];
+ if (fe->mask == AE_NONE) return;
+
+ /* We want to always remove AE_BARRIER if set when AE_WRITABLE
+ * is removed. */
+ if (mask & AE_WRITABLE) mask |= AE_BARRIER;
+
+ aeApiDelEvent(eventLoop, fd, mask);
+ 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;
+ }
+}
+
+void *aeGetFileClientData(aeEventLoop *eventLoop, int fd) {
+ if (fd >= eventLoop->setsize) return NULL;
+ aeFileEvent *fe = &eventLoop->events[fd];
+ if (fe->mask == AE_NONE) return NULL;
+
+ return fe->clientData;
+}
+
+int aeGetFileEvents(aeEventLoop *eventLoop, int fd) {
+ if (fd >= eventLoop->setsize) return 0;
+ aeFileEvent *fe = &eventLoop->events[fd];
+
+ return fe->mask;
+}
+
+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;
+ te->when = getMonotonicUs() + milliseconds * 1000;
+ te->timeProc = proc;
+ te->finalizerProc = finalizerProc;
+ te->clientData = clientData;
+ te->prev = NULL;
+ te->next = eventLoop->timeEventHead;
+ te->refcount = 0;
+ if (te->next)
+ te->next->prev = te;
+ eventLoop->timeEventHead = te;
+ return id;
+}
+
+int aeDeleteTimeEvent(aeEventLoop *eventLoop, long long id)
+{
+ aeTimeEvent *te = eventLoop->timeEventHead;
+ while(te) {
+ if (te->id == id) {
+ te->id = AE_DELETED_EVENT_ID;
+ return AE_OK;
+ }
+ te = te->next;
+ }
+ return AE_ERR; /* NO event with the specified ID found */
+}
+
+/* How many microseconds until the first timer should fire.
+ * If there are no timers, -1 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 int64_t usUntilEarliestTimer(aeEventLoop *eventLoop) {
+ aeTimeEvent *te = eventLoop->timeEventHead;
+ if (te == NULL) return -1;
+
+ aeTimeEvent *earliest = NULL;
+ while (te) {
+ if ((!earliest || te->when < earliest->when) && te->id != AE_DELETED_EVENT_ID)
+ earliest = te;
+ te = te->next;
+ }
+
+ monotime now = getMonotonicUs();
+ return (now >= earliest->when) ? 0 : earliest->when - now;
+}
+
+/* Process time events */
+static int processTimeEvents(aeEventLoop *eventLoop) {
+ int processed = 0;
+ aeTimeEvent *te;
+ long long maxId;
+
+ te = eventLoop->timeEventHead;
+ maxId = eventLoop->timeEventNextId-1;
+ monotime now = getMonotonicUs();
+ while(te) {
+ long long id;
+
+ /* Remove events scheduled for deletion. */
+ if (te->id == AE_DELETED_EVENT_ID) {
+ aeTimeEvent *next = te->next;
+ /* If a reference exists for this timer event,
+ * don't free it. This is currently incremented
+ * for recursive timerProc calls */
+ if (te->refcount) {
+ te = next;
+ continue;
+ }
+ if (te->prev)
+ te->prev->next = te->next;
+ else
+ eventLoop->timeEventHead = te->next;
+ if (te->next)
+ te->next->prev = te->prev;
+ if (te->finalizerProc) {
+ te->finalizerProc(eventLoop, te->clientData);
+ now = getMonotonicUs();
+ }
+ zfree(te);
+ te = next;
+ continue;
+ }
+
+ /* Make sure we don't process time events created by time events in
+ * this iteration. Note that this check is currently useless: we always
+ * add new timers on the head, however if we change the implementation
+ * detail, this check may be useful again: we keep it here for future
+ * defense. */
+ if (te->id > maxId) {
+ te = te->next;
+ continue;
+ }
+
+ if (te->when <= now) {
+ int retval;
+
+ id = te->id;
+ te->refcount++;
+ retval = te->timeProc(eventLoop, id, te->clientData);
+ te->refcount--;
+ processed++;
+ now = getMonotonicUs();
+ if (retval != AE_NOMORE) {
+ te->when = now + (monotime)retval * 1000;
+ } else {
+ te->id = AE_DELETED_EVENT_ID;
+ }
+ }
+ 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 occurs (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 once all
+ * the events that can be handled without a wait are processed.
+ * if flags has AE_CALL_AFTER_SLEEP set, the aftersleep callback is called.
+ * if flags has AE_CALL_BEFORE_SLEEP set, the beforesleep callback is called.
+ *
+ * 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 to call aeApiPoll() 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;
+ struct timeval tv, *tvp = NULL; /* NULL means infinite wait. */
+ int64_t usUntilTimer;
+
+ if (eventLoop->beforesleep != NULL && (flags & AE_CALL_BEFORE_SLEEP))
+ eventLoop->beforesleep(eventLoop);
+
+ /* The eventLoop->flags may be changed inside beforesleep.
+ * So we should check it after beforesleep be called. At the same time,
+ * the parameter flags always should have the highest priority.
+ * That is to say, once the parameter flag is set to AE_DONT_WAIT,
+ * no matter what value eventLoop->flags is set to, we should ignore it. */
+ if ((flags & AE_DONT_WAIT) || (eventLoop->flags & AE_DONT_WAIT)) {
+ tv.tv_sec = tv.tv_usec = 0;
+ tvp = &tv;
+ } else if (flags & AE_TIME_EVENTS) {
+ usUntilTimer = usUntilEarliestTimer(eventLoop);
+ if (usUntilTimer >= 0) {
+ tv.tv_sec = usUntilTimer / 1000000;
+ tv.tv_usec = usUntilTimer % 1000000;
+ tvp = &tv;
+ }
+ }
+ /* Call the multiplexing API, will return only on timeout or when
+ * some event fires. */
+ numevents = aeApiPoll(eventLoop, tvp);
+
+ /* Don't process file events if not requested. */
+ if (!(flags & AE_FILE_EVENTS)) {
+ numevents = 0;
+ }
+
+ /* After sleep callback. */
+ if (eventLoop->aftersleep != NULL && flags & AE_CALL_AFTER_SLEEP)
+ eventLoop->aftersleep(eventLoop);
+
+ for (j = 0; j < numevents; j++) {
+ int fd = eventLoop->fired[j].fd;
+ aeFileEvent *fe = &eventLoop->events[fd];
+ int mask = eventLoop->fired[j].mask;
+ int fired = 0; /* Number of events fired for current fd. */
+
+ /* Normally we execute the readable event first, and the writable
+ * event later. This is useful as sometimes we may be able
+ * to serve the reply of a query immediately after processing the
+ * query.
+ *
+ * However if AE_BARRIER is set in the mask, our application is
+ * asking us to do the reverse: never fire the writable event
+ * after the readable. In such a case, we invert the calls.
+ * This is useful when, for instance, we want to do things
+ * in the beforeSleep() hook, like fsyncing a file to disk,
+ * before replying to a client. */
+ int invert = fe->mask & AE_BARRIER;
+
+ /* 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.
+ *
+ * Fire the readable event if the call sequence is not
+ * inverted. */
+ if (!invert && fe->mask & mask & AE_READABLE) {
+ fe->rfileProc(eventLoop,fd,fe->clientData,mask);
+ fired++;
+ fe = &eventLoop->events[fd]; /* Refresh in case of resize. */
+ }
+
+ /* Fire the writable event. */
+ if (fe->mask & mask & AE_WRITABLE) {
+ if (!fired || fe->wfileProc != fe->rfileProc) {
+ fe->wfileProc(eventLoop,fd,fe->clientData,mask);
+ fired++;
+ }
+ }
+
+ /* If we have to invert the call, fire the readable event now
+ * after the writable one. */
+ if (invert) {
+ fe = &eventLoop->events[fd]; /* Refresh in case of resize. */
+ if ((fe->mask & mask & AE_READABLE) &&
+ (!fired || fe->wfileProc != fe->rfileProc))
+ {
+ fe->rfileProc(eventLoop,fd,fe->clientData,mask);
+ fired++;
+ }
+ }
+
+ processed++;
+ }
+ }
+ /* Check time events */
+ if (flags & AE_TIME_EVENTS)
+ processed += processTimeEvents(eventLoop);
+
+ return processed; /* return the number of processed file/time events */
+}
+
+/* Wait for milliseconds until the given file descriptor becomes
+ * writable/readable/exception */
+int aeWait(int fd, int mask, long long milliseconds) {
+ struct pollfd pfd;
+ int retmask = 0, retval;
+
+ memset(&pfd, 0, sizeof(pfd));
+ pfd.fd = fd;
+ if (mask & AE_READABLE) pfd.events |= POLLIN;
+ if (mask & AE_WRITABLE) pfd.events |= POLLOUT;
+
+ if ((retval = poll(&pfd, 1, milliseconds))== 1) {
+ if (pfd.revents & POLLIN) retmask |= AE_READABLE;
+ if (pfd.revents & POLLOUT) retmask |= AE_WRITABLE;
+ if (pfd.revents & POLLERR) retmask |= AE_WRITABLE;
+ if (pfd.revents & POLLHUP) retmask |= AE_WRITABLE;
+ return retmask;
+ } else {
+ return retval;
+ }
+}
+
+void aeMain(aeEventLoop *eventLoop) {
+ eventLoop->stop = 0;
+ while (!eventLoop->stop) {
+ aeProcessEvents(eventLoop, AE_ALL_EVENTS|
+ AE_CALL_BEFORE_SLEEP|
+ AE_CALL_AFTER_SLEEP);
+ }
+}
+
+char *aeGetApiName(void) {
+ return aeApiName();
+}
+
+void aeSetBeforeSleepProc(aeEventLoop *eventLoop, aeBeforeSleepProc *beforesleep) {
+ eventLoop->beforesleep = beforesleep;
+}
+
+void aeSetAfterSleepProc(aeEventLoop *eventLoop, aeBeforeSleepProc *aftersleep) {
+ eventLoop->aftersleep = aftersleep;
+}