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-rw-r--r--contrib/bind9/lib/bind/isc/eventlib.c728
1 files changed, 728 insertions, 0 deletions
diff --git a/contrib/bind9/lib/bind/isc/eventlib.c b/contrib/bind9/lib/bind/isc/eventlib.c
new file mode 100644
index 0000000..527fec1
--- /dev/null
+++ b/contrib/bind9/lib/bind/isc/eventlib.c
@@ -0,0 +1,728 @@
+/*
+ * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (c) 1995-1999 by Internet Software Consortium
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+ * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* eventlib.c - implement glue for the eventlib
+ * vix 09sep95 [initial]
+ */
+
+#if !defined(LINT) && !defined(CODECENTER)
+static const char rcsid[] = "$Id: eventlib.c,v 1.2.2.1.4.2 2004/03/17 01:49:41 marka Exp $";
+#endif
+
+#include "port_before.h"
+#include "fd_setsize.h"
+
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/stat.h>
+
+#include <errno.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <isc/eventlib.h>
+#include <isc/assertions.h>
+#include "eventlib_p.h"
+
+#include "port_after.h"
+
+/* Forward. */
+
+#ifdef NEED_PSELECT
+static int pselect(int, void *, void *, void *,
+ struct timespec *,
+ const sigset_t *);
+#endif
+
+/* Public. */
+
+int
+evCreate(evContext *opaqueCtx) {
+ evContext_p *ctx;
+
+ /* Make sure the memory heap is initialized. */
+ if (meminit(0, 0) < 0 && errno != EEXIST)
+ return (-1);
+
+ OKNEW(ctx);
+
+ /* Global. */
+ ctx->cur = NULL;
+
+ /* Debugging. */
+ ctx->debug = 0;
+ ctx->output = NULL;
+
+ /* Connections. */
+ ctx->conns = NULL;
+ INIT_LIST(ctx->accepts);
+
+ /* Files. */
+ ctx->files = NULL;
+ FD_ZERO(&ctx->rdNext);
+ FD_ZERO(&ctx->wrNext);
+ FD_ZERO(&ctx->exNext);
+ FD_ZERO(&ctx->nonblockBefore);
+ ctx->fdMax = -1;
+ ctx->fdNext = NULL;
+ ctx->fdCount = 0; /* Invalidate {rd,wr,ex}Last. */
+ ctx->highestFD = FD_SETSIZE - 1;
+#ifdef EVENTLIB_TIME_CHECKS
+ ctx->lastFdCount = 0;
+#endif
+ memset(ctx->fdTable, 0, sizeof ctx->fdTable);
+
+ /* Streams. */
+ ctx->streams = NULL;
+ ctx->strDone = NULL;
+ ctx->strLast = NULL;
+
+ /* Timers. */
+ ctx->lastEventTime = evNowTime();
+#ifdef EVENTLIB_TIME_CHECKS
+ ctx->lastSelectTime = ctx->lastEventTime;
+#endif
+ ctx->timers = evCreateTimers(ctx);
+ if (ctx->timers == NULL)
+ return (-1);
+
+ /* Waits. */
+ ctx->waitLists = NULL;
+ ctx->waitDone.first = ctx->waitDone.last = NULL;
+ ctx->waitDone.prev = ctx->waitDone.next = NULL;
+
+ opaqueCtx->opaque = ctx;
+ return (0);
+}
+
+void
+evSetDebug(evContext opaqueCtx, int level, FILE *output) {
+ evContext_p *ctx = opaqueCtx.opaque;
+
+ ctx->debug = level;
+ ctx->output = output;
+}
+
+int
+evDestroy(evContext opaqueCtx) {
+ evContext_p *ctx = opaqueCtx.opaque;
+ int revs = 424242; /* Doug Adams. */
+ evWaitList *this_wl, *next_wl;
+ evWait *this_wait, *next_wait;
+
+ /* Connections. */
+ while (revs-- > 0 && ctx->conns != NULL) {
+ evConnID id;
+
+ id.opaque = ctx->conns;
+ (void) evCancelConn(opaqueCtx, id);
+ }
+ INSIST(revs >= 0);
+
+ /* Streams. */
+ while (revs-- > 0 && ctx->streams != NULL) {
+ evStreamID id;
+
+ id.opaque = ctx->streams;
+ (void) evCancelRW(opaqueCtx, id);
+ }
+
+ /* Files. */
+ while (revs-- > 0 && ctx->files != NULL) {
+ evFileID id;
+
+ id.opaque = ctx->files;
+ (void) evDeselectFD(opaqueCtx, id);
+ }
+ INSIST(revs >= 0);
+
+ /* Timers. */
+ evDestroyTimers(ctx);
+
+ /* Waits. */
+ for (this_wl = ctx->waitLists;
+ revs-- > 0 && this_wl != NULL;
+ this_wl = next_wl) {
+ next_wl = this_wl->next;
+ for (this_wait = this_wl->first;
+ revs-- > 0 && this_wait != NULL;
+ this_wait = next_wait) {
+ next_wait = this_wait->next;
+ FREE(this_wait);
+ }
+ FREE(this_wl);
+ }
+ for (this_wait = ctx->waitDone.first;
+ revs-- > 0 && this_wait != NULL;
+ this_wait = next_wait) {
+ next_wait = this_wait->next;
+ FREE(this_wait);
+ }
+
+ FREE(ctx);
+ return (0);
+}
+
+int
+evGetNext(evContext opaqueCtx, evEvent *opaqueEv, int options) {
+ evContext_p *ctx = opaqueCtx.opaque;
+ struct timespec nextTime;
+ evTimer *nextTimer;
+ evEvent_p *new;
+ int x, pselect_errno, timerPast;
+#ifdef EVENTLIB_TIME_CHECKS
+ struct timespec interval;
+#endif
+
+ /* Ensure that exactly one of EV_POLL or EV_WAIT was specified. */
+ x = ((options & EV_POLL) != 0) + ((options & EV_WAIT) != 0);
+ if (x != 1)
+ EV_ERR(EINVAL);
+
+ /* Get the time of day. We'll do this again after select() blocks. */
+ ctx->lastEventTime = evNowTime();
+
+ again:
+ /* Finished accept()'s do not require a select(). */
+ if (!EMPTY(ctx->accepts)) {
+ OKNEW(new);
+ new->type = Accept;
+ new->u.accept.this = HEAD(ctx->accepts);
+ UNLINK(ctx->accepts, HEAD(ctx->accepts), link);
+ opaqueEv->opaque = new;
+ return (0);
+ }
+
+ /* Stream IO does not require a select(). */
+ if (ctx->strDone != NULL) {
+ OKNEW(new);
+ new->type = Stream;
+ new->u.stream.this = ctx->strDone;
+ ctx->strDone = ctx->strDone->nextDone;
+ if (ctx->strDone == NULL)
+ ctx->strLast = NULL;
+ opaqueEv->opaque = new;
+ return (0);
+ }
+
+ /* Waits do not require a select(). */
+ if (ctx->waitDone.first != NULL) {
+ OKNEW(new);
+ new->type = Wait;
+ new->u.wait.this = ctx->waitDone.first;
+ ctx->waitDone.first = ctx->waitDone.first->next;
+ if (ctx->waitDone.first == NULL)
+ ctx->waitDone.last = NULL;
+ opaqueEv->opaque = new;
+ return (0);
+ }
+
+ /* Get the status and content of the next timer. */
+ if ((nextTimer = heap_element(ctx->timers, 1)) != NULL) {
+ nextTime = nextTimer->due;
+ timerPast = (evCmpTime(nextTime, ctx->lastEventTime) <= 0);
+ } else
+ timerPast = 0; /* Make gcc happy. */
+
+ evPrintf(ctx, 9, "evGetNext: fdCount %d\n", ctx->fdCount);
+ if (ctx->fdCount == 0) {
+ static const struct timespec NoTime = {0, 0L};
+ enum { JustPoll, Block, Timer } m;
+ struct timespec t, *tp;
+
+ /* Are there any events at all? */
+ if ((options & EV_WAIT) != 0 && !nextTimer && ctx->fdMax == -1)
+ EV_ERR(ENOENT);
+
+ /* Figure out what select()'s timeout parameter should be. */
+ if ((options & EV_POLL) != 0) {
+ m = JustPoll;
+ t = NoTime;
+ tp = &t;
+ } else if (nextTimer == NULL) {
+ m = Block;
+ /* ``t'' unused. */
+ tp = NULL;
+ } else if (timerPast) {
+ m = JustPoll;
+ t = NoTime;
+ tp = &t;
+ } else {
+ m = Timer;
+ /* ``t'' filled in later. */
+ tp = &t;
+ }
+#ifdef EVENTLIB_TIME_CHECKS
+ if (ctx->debug > 0) {
+ interval = evSubTime(ctx->lastEventTime,
+ ctx->lastSelectTime);
+ if (interval.tv_sec > 0 || interval.tv_nsec > 0)
+ evPrintf(ctx, 1,
+ "time between pselect() %u.%09u count %d\n",
+ interval.tv_sec, interval.tv_nsec,
+ ctx->lastFdCount);
+ }
+#endif
+ do {
+ /* XXX need to copy only the bits we are using. */
+ ctx->rdLast = ctx->rdNext;
+ ctx->wrLast = ctx->wrNext;
+ ctx->exLast = ctx->exNext;
+
+ if (m == Timer) {
+ INSIST(tp == &t);
+ t = evSubTime(nextTime, ctx->lastEventTime);
+ }
+
+ evPrintf(ctx, 4,
+ "pselect(%d, 0x%lx, 0x%lx, 0x%lx, %ld.%09ld)\n",
+ ctx->fdMax+1,
+ (u_long)ctx->rdLast.fds_bits[0],
+ (u_long)ctx->wrLast.fds_bits[0],
+ (u_long)ctx->exLast.fds_bits[0],
+ tp ? (long)tp->tv_sec : -1L,
+ tp ? tp->tv_nsec : -1);
+
+ /* XXX should predict system's earliness and adjust. */
+ x = pselect(ctx->fdMax+1,
+ &ctx->rdLast, &ctx->wrLast, &ctx->exLast,
+ tp, NULL);
+ pselect_errno = errno;
+
+ evPrintf(ctx, 4, "select() returns %d (err: %s)\n",
+ x, (x == -1) ? strerror(errno) : "none");
+
+ /* Anything but a poll can change the time. */
+ if (m != JustPoll)
+ ctx->lastEventTime = evNowTime();
+
+ /* Select() likes to finish about 10ms early. */
+ } while (x == 0 && m == Timer &&
+ evCmpTime(ctx->lastEventTime, nextTime) < 0);
+#ifdef EVENTLIB_TIME_CHECKS
+ ctx->lastSelectTime = ctx->lastEventTime;
+#endif
+ if (x < 0) {
+ if (pselect_errno == EINTR) {
+ if ((options & EV_NULL) != 0)
+ goto again;
+ OKNEW(new);
+ new->type = Null;
+ /* No data. */
+ opaqueEv->opaque = new;
+ return (0);
+ }
+ if (pselect_errno == EBADF) {
+ for (x = 0; x <= ctx->fdMax; x++) {
+ struct stat sb;
+
+ if (FD_ISSET(x, &ctx->rdNext) == 0 &&
+ FD_ISSET(x, &ctx->wrNext) == 0 &&
+ FD_ISSET(x, &ctx->exNext) == 0)
+ continue;
+ if (fstat(x, &sb) == -1 &&
+ errno == EBADF)
+ evPrintf(ctx, 1, "EBADF: %d\n",
+ x);
+ }
+ abort();
+ }
+ EV_ERR(pselect_errno);
+ }
+ if (x == 0 && (nextTimer == NULL || !timerPast) &&
+ (options & EV_POLL))
+ EV_ERR(EWOULDBLOCK);
+ ctx->fdCount = x;
+#ifdef EVENTLIB_TIME_CHECKS
+ ctx->lastFdCount = x;
+#endif
+ }
+ INSIST(nextTimer || ctx->fdCount);
+
+ /* Timers go first since we'd like them to be accurate. */
+ if (nextTimer && !timerPast) {
+ /* Has anything happened since we blocked? */
+ timerPast = (evCmpTime(nextTime, ctx->lastEventTime) <= 0);
+ }
+ if (nextTimer && timerPast) {
+ OKNEW(new);
+ new->type = Timer;
+ new->u.timer.this = nextTimer;
+ opaqueEv->opaque = new;
+ return (0);
+ }
+
+ /* No timers, so there should be a ready file descriptor. */
+ x = 0;
+ while (ctx->fdCount > 0) {
+ evFile *fid;
+ int fd, eventmask;
+
+ if (ctx->fdNext == NULL) {
+ if (++x == 2) {
+ /*
+ * Hitting the end twice means that the last
+ * select() found some FD's which have since
+ * been deselected.
+ *
+ * On some systems, the count returned by
+ * selects is the total number of bits in
+ * all masks that are set, and on others it's
+ * the number of fd's that have some bit set,
+ * and on others, it's just broken. We
+ * always assume that it's the number of
+ * bits set in all masks, because that's what
+ * the man page says it should do, and
+ * the worst that can happen is we do an
+ * extra select().
+ */
+ ctx->fdCount = 0;
+ break;
+ }
+ ctx->fdNext = ctx->files;
+ }
+ fid = ctx->fdNext;
+ ctx->fdNext = fid->next;
+
+ fd = fid->fd;
+ eventmask = 0;
+ if (FD_ISSET(fd, &ctx->rdLast))
+ eventmask |= EV_READ;
+ if (FD_ISSET(fd, &ctx->wrLast))
+ eventmask |= EV_WRITE;
+ if (FD_ISSET(fd, &ctx->exLast))
+ eventmask |= EV_EXCEPT;
+ eventmask &= fid->eventmask;
+ if (eventmask != 0) {
+ if ((eventmask & EV_READ) != 0) {
+ FD_CLR(fd, &ctx->rdLast);
+ ctx->fdCount--;
+ }
+ if ((eventmask & EV_WRITE) != 0) {
+ FD_CLR(fd, &ctx->wrLast);
+ ctx->fdCount--;
+ }
+ if ((eventmask & EV_EXCEPT) != 0) {
+ FD_CLR(fd, &ctx->exLast);
+ ctx->fdCount--;
+ }
+ OKNEW(new);
+ new->type = File;
+ new->u.file.this = fid;
+ new->u.file.eventmask = eventmask;
+ opaqueEv->opaque = new;
+ return (0);
+ }
+ }
+ if (ctx->fdCount < 0) {
+ /*
+ * select()'s count is off on a number of systems, and
+ * can result in fdCount < 0.
+ */
+ evPrintf(ctx, 4, "fdCount < 0 (%d)\n", ctx->fdCount);
+ ctx->fdCount = 0;
+ }
+
+ /* We get here if the caller deselect()'s an FD. Gag me with a goto. */
+ goto again;
+}
+
+int
+evDispatch(evContext opaqueCtx, evEvent opaqueEv) {
+ evContext_p *ctx = opaqueCtx.opaque;
+ evEvent_p *ev = opaqueEv.opaque;
+#ifdef EVENTLIB_TIME_CHECKS
+ void *func;
+ struct timespec start_time;
+ struct timespec interval;
+#endif
+
+#ifdef EVENTLIB_TIME_CHECKS
+ if (ctx->debug > 0)
+ start_time = evNowTime();
+#endif
+ ctx->cur = ev;
+ switch (ev->type) {
+ case Accept: {
+ evAccept *this = ev->u.accept.this;
+
+ evPrintf(ctx, 5,
+ "Dispatch.Accept: fd %d -> %d, func %p, uap %p\n",
+ this->conn->fd, this->fd,
+ this->conn->func, this->conn->uap);
+ errno = this->ioErrno;
+ (this->conn->func)(opaqueCtx, this->conn->uap, this->fd,
+ &this->la, this->lalen,
+ &this->ra, this->ralen);
+#ifdef EVENTLIB_TIME_CHECKS
+ func = this->conn->func;
+#endif
+ break;
+ }
+ case File: {
+ evFile *this = ev->u.file.this;
+ int eventmask = ev->u.file.eventmask;
+
+ evPrintf(ctx, 5,
+ "Dispatch.File: fd %d, mask 0x%x, func %p, uap %p\n",
+ this->fd, this->eventmask, this->func, this->uap);
+ (this->func)(opaqueCtx, this->uap, this->fd, eventmask);
+#ifdef EVENTLIB_TIME_CHECKS
+ func = this->func;
+#endif
+ break;
+ }
+ case Stream: {
+ evStream *this = ev->u.stream.this;
+
+ evPrintf(ctx, 5,
+ "Dispatch.Stream: fd %d, func %p, uap %p\n",
+ this->fd, this->func, this->uap);
+ errno = this->ioErrno;
+ (this->func)(opaqueCtx, this->uap, this->fd, this->ioDone);
+#ifdef EVENTLIB_TIME_CHECKS
+ func = this->func;
+#endif
+ break;
+ }
+ case Timer: {
+ evTimer *this = ev->u.timer.this;
+
+ evPrintf(ctx, 5, "Dispatch.Timer: func %p, uap %p\n",
+ this->func, this->uap);
+ (this->func)(opaqueCtx, this->uap, this->due, this->inter);
+#ifdef EVENTLIB_TIME_CHECKS
+ func = this->func;
+#endif
+ break;
+ }
+ case Wait: {
+ evWait *this = ev->u.wait.this;
+
+ evPrintf(ctx, 5,
+ "Dispatch.Wait: tag %p, func %p, uap %p\n",
+ this->tag, this->func, this->uap);
+ (this->func)(opaqueCtx, this->uap, this->tag);
+#ifdef EVENTLIB_TIME_CHECKS
+ func = this->func;
+#endif
+ break;
+ }
+ case Null: {
+ /* No work. */
+#ifdef EVENTLIB_TIME_CHECKS
+ func = NULL;
+#endif
+ break;
+ }
+ default: {
+ abort();
+ }
+ }
+#ifdef EVENTLIB_TIME_CHECKS
+ if (ctx->debug > 0) {
+ interval = evSubTime(evNowTime(), start_time);
+ /*
+ * Complain if it took longer than 50 milliseconds.
+ *
+ * We call getuid() to make an easy to find mark in a kernel
+ * trace.
+ */
+ if (interval.tv_sec > 0 || interval.tv_nsec > 50000000)
+ evPrintf(ctx, 1,
+ "dispatch interval %u.%09u uid %d type %d func %p\n",
+ interval.tv_sec, interval.tv_nsec,
+ getuid(), ev->type, func);
+ }
+#endif
+ ctx->cur = NULL;
+ evDrop(opaqueCtx, opaqueEv);
+ return (0);
+}
+
+void
+evDrop(evContext opaqueCtx, evEvent opaqueEv) {
+ evContext_p *ctx = opaqueCtx.opaque;
+ evEvent_p *ev = opaqueEv.opaque;
+
+ switch (ev->type) {
+ case Accept: {
+ FREE(ev->u.accept.this);
+ break;
+ }
+ case File: {
+ /* No work. */
+ break;
+ }
+ case Stream: {
+ evStreamID id;
+
+ id.opaque = ev->u.stream.this;
+ (void) evCancelRW(opaqueCtx, id);
+ break;
+ }
+ case Timer: {
+ evTimer *this = ev->u.timer.this;
+ evTimerID opaque;
+
+ /* Check to see whether the user func cleared the timer. */
+ if (heap_element(ctx->timers, this->index) != this) {
+ evPrintf(ctx, 5, "Dispatch.Timer: timer rm'd?\n");
+ break;
+ }
+ /*
+ * Timer is still there. Delete it if it has expired,
+ * otherwise set it according to its next interval.
+ */
+ if (this->inter.tv_sec == (time_t)0 &&
+ this->inter.tv_nsec == 0L) {
+ opaque.opaque = this;
+ (void) evClearTimer(opaqueCtx, opaque);
+ } else {
+ opaque.opaque = this;
+ (void) evResetTimer(opaqueCtx, opaque, this->func,
+ this->uap,
+ evAddTime((this->mode & EV_TMR_RATE) ?
+ this->due :
+ ctx->lastEventTime,
+ this->inter),
+ this->inter);
+ }
+ break;
+ }
+ case Wait: {
+ FREE(ev->u.wait.this);
+ break;
+ }
+ case Null: {
+ /* No work. */
+ break;
+ }
+ default: {
+ abort();
+ }
+ }
+ FREE(ev);
+}
+
+int
+evMainLoop(evContext opaqueCtx) {
+ evEvent event;
+ int x;
+
+ while ((x = evGetNext(opaqueCtx, &event, EV_WAIT)) == 0)
+ if ((x = evDispatch(opaqueCtx, event)) < 0)
+ break;
+ return (x);
+}
+
+int
+evHighestFD(evContext opaqueCtx) {
+ evContext_p *ctx = opaqueCtx.opaque;
+
+ return (ctx->highestFD);
+}
+
+void
+evPrintf(const evContext_p *ctx, int level, const char *fmt, ...) {
+ va_list ap;
+
+ va_start(ap, fmt);
+ if (ctx->output != NULL && ctx->debug >= level) {
+ vfprintf(ctx->output, fmt, ap);
+ fflush(ctx->output);
+ }
+ va_end(ap);
+}
+
+int
+evSetOption(evContext *opaqueCtx, const char *option, int value) {
+ /* evContext_p *ctx = opaqueCtx->opaque; */
+
+ UNUSED(opaqueCtx);
+ UNUSED(value);
+#ifndef CLOCK_MONOTONIC
+ UNUSED(option);
+#endif
+
+#ifdef CLOCK_MONOTONIC
+ if (strcmp(option, "monotime") == 0) {
+ if (opaqueCtx != NULL)
+ errno = EINVAL;
+ if (value == 0 || value == 1) {
+ __evOptMonoTime = value;
+ return (0);
+ } else {
+ errno = EINVAL;
+ return (-1);
+ }
+ }
+#endif
+ errno = ENOENT;
+ return (-1);
+}
+
+int
+evGetOption(evContext *opaqueCtx, const char *option, int *value) {
+ /* evContext_p *ctx = opaqueCtx->opaque; */
+
+ UNUSED(opaqueCtx);
+#ifndef CLOCK_MONOTONIC
+ UNUSED(value);
+ UNUSED(option);
+#endif
+
+#ifdef CLOCK_MONOTONIC
+ if (strcmp(option, "monotime") == 0) {
+ if (opaqueCtx != NULL)
+ errno = EINVAL;
+ *value = __evOptMonoTime;
+ return (0);
+ }
+#endif
+ errno = ENOENT;
+ return (-1);
+}
+
+#ifdef NEED_PSELECT
+/* XXX needs to move to the porting library. */
+static int
+pselect(int nfds, void *rfds, void *wfds, void *efds,
+ struct timespec *tsp,
+ const sigset_t *sigmask)
+{
+ struct timeval tv, *tvp;
+ sigset_t sigs;
+ int n;
+
+ if (tsp) {
+ tvp = &tv;
+ tv = evTimeVal(*tsp);
+ } else
+ tvp = NULL;
+ if (sigmask)
+ sigprocmask(SIG_SETMASK, sigmask, &sigs);
+ n = select(nfds, rfds, wfds, efds, tvp);
+ if (sigmask)
+ sigprocmask(SIG_SETMASK, &sigs, NULL);
+ if (tsp)
+ *tsp = evTimeSpec(tv);
+ return (n);
+}
+#endif
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