util: delete the poll() based event loop impl

It is no longer require since switching to the GLib based
event loop impl.

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2020-01-14 12:40:14 +00:00
parent 946a25274c
commit 55fe8110af
6 changed files with 0 additions and 930 deletions

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@ -238,7 +238,6 @@
@SRCDIR@/src/util/virerror.c
@SRCDIR@/src/util/virerror.h
@SRCDIR@/src/util/virevent.c
@SRCDIR@/src/util/vireventpoll.c
@SRCDIR@/src/util/virfcp.c
@SRCDIR@/src/util/virfdstream.c
@SRCDIR@/src/util/virfile.c

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@ -1938,19 +1938,6 @@ virEventGLibRegister;
virEventGLibRunOnce;
# util/vireventpoll.h
virEventPollAddHandle;
virEventPollAddTimeout;
virEventPollFromNativeEvents;
virEventPollInit;
virEventPollRemoveHandle;
virEventPollRemoveTimeout;
virEventPollRunOnce;
virEventPollToNativeEvents;
virEventPollUpdateHandle;
virEventPollUpdateTimeout;
# util/virfcp.h
virFCIsCapableRport;
virFCReadRportValue;

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@ -1,20 +1,4 @@
provider libvirt {
# file: src/util/event_poll.c
# prefix: event_poll
probe event_poll_add_handle(int watch, int fd, int events, void *cb, void *opaque, void *ff);
probe event_poll_update_handle(int watch, int events);
probe event_poll_remove_handle(int watch);
probe event_poll_dispatch_handle(int watch, int events);
probe event_poll_purge_handle(int watch);
probe event_poll_add_timeout(int timer, int frequency, void *cb, void *opaque, void *ff);
probe event_poll_update_timeout(int timer, int frequency);
probe event_poll_remove_timeout(int timer);
probe event_poll_dispatch_timeout(int timer);
probe event_poll_purge_timeout(int timer);
probe event_poll_run(int nfds, int timeout);
# file: src/util/vireventglib.c
# prefix: event_glib
probe event_glib_add_handle(int watch, int fd, int events, void *cb, void *opaque, void *ff);

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@ -65,8 +65,6 @@ UTIL_SOURCES = \
util/vireventglib.h \
util/vireventglibwatch.c \
util/vireventglibwatch.h \
util/vireventpoll.c \
util/vireventpoll.h \
util/virfcp.c \
util/virfcp.h \
util/virfdstream.c \

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@ -1,772 +0,0 @@
/*
* vireventpoll.c: Poll based event loop for monitoring file handles
*
* Copyright (C) 2007, 2010-2014 Red Hat, Inc.
* Copyright (C) 2007 Daniel P. Berrange
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include <poll.h>
#include <sys/time.h>
#include <unistd.h>
#include <fcntl.h>
#include "virthread.h"
#include "virlog.h"
#include "vireventpoll.h"
#include "viralloc.h"
#include "virutil.h"
#include "virfile.h"
#include "virerror.h"
#include "virprobe.h"
#include "virtime.h"
#define EVENT_DEBUG(fmt, ...) VIR_DEBUG(fmt, __VA_ARGS__)
#define VIR_FROM_THIS VIR_FROM_EVENT
VIR_LOG_INIT("util.eventpoll");
static int virEventPollInterruptLocked(void);
/* State for a single file handle being monitored */
struct virEventPollHandle {
int watch;
int fd;
int events;
virEventHandleCallback cb;
virFreeCallback ff;
void *opaque;
int deleted;
};
/* State for a single timer being generated */
struct virEventPollTimeout {
int timer;
int frequency;
unsigned long long expiresAt;
virEventTimeoutCallback cb;
virFreeCallback ff;
void *opaque;
int deleted;
};
/* Allocate extra slots for virEventPollHandle/virEventPollTimeout
records in this multiple */
#define EVENT_ALLOC_EXTENT 10
/* State for the main event loop */
struct virEventPollLoop {
virMutex lock;
int running;
virThread leader;
int wakeupfd[2];
size_t handlesCount;
size_t handlesAlloc;
struct virEventPollHandle *handles;
size_t timeoutsCount;
size_t timeoutsAlloc;
struct virEventPollTimeout *timeouts;
};
/* Only have one event loop */
static struct virEventPollLoop eventLoop;
/* Unique ID for the next FD watch to be registered */
static int nextWatch = 1;
/* Unique ID for the next timer to be registered */
static int nextTimer = 1;
/*
* Register a callback for monitoring file handle events.
* NB, it *must* be safe to call this from within a callback
* For this reason we only ever append to existing list.
*/
int virEventPollAddHandle(int fd, int events,
virEventHandleCallback cb,
void *opaque,
virFreeCallback ff)
{
int watch;
virMutexLock(&eventLoop.lock);
if (eventLoop.handlesCount == eventLoop.handlesAlloc) {
EVENT_DEBUG("Used %zu handle slots, adding at least %d more",
eventLoop.handlesAlloc, EVENT_ALLOC_EXTENT);
if (VIR_RESIZE_N(eventLoop.handles, eventLoop.handlesAlloc,
eventLoop.handlesCount, EVENT_ALLOC_EXTENT) < 0) {
virMutexUnlock(&eventLoop.lock);
return -1;
}
}
watch = nextWatch++;
eventLoop.handles[eventLoop.handlesCount].watch = watch;
eventLoop.handles[eventLoop.handlesCount].fd = fd;
eventLoop.handles[eventLoop.handlesCount].events =
virEventPollToNativeEvents(events);
eventLoop.handles[eventLoop.handlesCount].cb = cb;
eventLoop.handles[eventLoop.handlesCount].ff = ff;
eventLoop.handles[eventLoop.handlesCount].opaque = opaque;
eventLoop.handles[eventLoop.handlesCount].deleted = 0;
eventLoop.handlesCount++;
virEventPollInterruptLocked();
PROBE(EVENT_POLL_ADD_HANDLE,
"watch=%d fd=%d events=%d cb=%p opaque=%p ff=%p",
watch, fd, events, cb, opaque, ff);
virMutexUnlock(&eventLoop.lock);
return watch;
}
void virEventPollUpdateHandle(int watch, int events)
{
size_t i;
bool found = false;
PROBE(EVENT_POLL_UPDATE_HANDLE,
"watch=%d events=%d",
watch, events);
if (watch <= 0) {
VIR_WARN("Ignoring invalid update watch %d", watch);
return;
}
virMutexLock(&eventLoop.lock);
for (i = 0; i < eventLoop.handlesCount; i++) {
if (eventLoop.handles[i].watch == watch) {
eventLoop.handles[i].events =
virEventPollToNativeEvents(events);
virEventPollInterruptLocked();
found = true;
break;
}
}
virMutexUnlock(&eventLoop.lock);
if (!found)
VIR_WARN("Got update for non-existent handle watch %d", watch);
}
/*
* Unregister a callback from a file handle
* NB, it *must* be safe to call this from within a callback
* For this reason we only ever set a flag in the existing list.
* Actual deletion will be done out-of-band
*/
int virEventPollRemoveHandle(int watch)
{
size_t i;
PROBE(EVENT_POLL_REMOVE_HANDLE,
"watch=%d",
watch);
if (watch <= 0) {
VIR_WARN("Ignoring invalid remove watch %d", watch);
return -1;
}
virMutexLock(&eventLoop.lock);
for (i = 0; i < eventLoop.handlesCount; i++) {
if (eventLoop.handles[i].deleted)
continue;
if (eventLoop.handles[i].watch == watch) {
EVENT_DEBUG("mark delete %zu %d", i, eventLoop.handles[i].fd);
eventLoop.handles[i].deleted = 1;
virEventPollInterruptLocked();
virMutexUnlock(&eventLoop.lock);
return 0;
}
}
virMutexUnlock(&eventLoop.lock);
return -1;
}
/*
* Register a callback for a timer event
* NB, it *must* be safe to call this from within a callback
* For this reason we only ever append to existing list.
*/
int virEventPollAddTimeout(int frequency,
virEventTimeoutCallback cb,
void *opaque,
virFreeCallback ff)
{
unsigned long long now;
int ret;
if (virTimeMillisNow(&now) < 0)
return -1;
virMutexLock(&eventLoop.lock);
if (eventLoop.timeoutsCount == eventLoop.timeoutsAlloc) {
EVENT_DEBUG("Used %zu timeout slots, adding at least %d more",
eventLoop.timeoutsAlloc, EVENT_ALLOC_EXTENT);
if (VIR_RESIZE_N(eventLoop.timeouts, eventLoop.timeoutsAlloc,
eventLoop.timeoutsCount, EVENT_ALLOC_EXTENT) < 0) {
virMutexUnlock(&eventLoop.lock);
return -1;
}
}
eventLoop.timeouts[eventLoop.timeoutsCount].timer = nextTimer++;
eventLoop.timeouts[eventLoop.timeoutsCount].frequency = frequency;
eventLoop.timeouts[eventLoop.timeoutsCount].cb = cb;
eventLoop.timeouts[eventLoop.timeoutsCount].ff = ff;
eventLoop.timeouts[eventLoop.timeoutsCount].opaque = opaque;
eventLoop.timeouts[eventLoop.timeoutsCount].deleted = 0;
eventLoop.timeouts[eventLoop.timeoutsCount].expiresAt =
frequency >= 0 ? frequency + now : 0;
eventLoop.timeoutsCount++;
ret = nextTimer-1;
virEventPollInterruptLocked();
PROBE(EVENT_POLL_ADD_TIMEOUT,
"timer=%d frequency=%d cb=%p opaque=%p ff=%p",
ret, frequency, cb, opaque, ff);
virMutexUnlock(&eventLoop.lock);
return ret;
}
void virEventPollUpdateTimeout(int timer, int frequency)
{
unsigned long long now;
size_t i;
bool found = false;
PROBE(EVENT_POLL_UPDATE_TIMEOUT,
"timer=%d frequency=%d",
timer, frequency);
if (timer <= 0) {
VIR_WARN("Ignoring invalid update timer %d", timer);
return;
}
if (virTimeMillisNow(&now) < 0)
return;
virMutexLock(&eventLoop.lock);
for (i = 0; i < eventLoop.timeoutsCount; i++) {
if (eventLoop.timeouts[i].timer == timer) {
eventLoop.timeouts[i].frequency = frequency;
eventLoop.timeouts[i].expiresAt =
frequency >= 0 ? frequency + now : 0;
VIR_DEBUG("Set timer freq=%d expires=%llu", frequency,
eventLoop.timeouts[i].expiresAt);
virEventPollInterruptLocked();
found = true;
break;
}
}
virMutexUnlock(&eventLoop.lock);
if (!found)
VIR_WARN("Got update for non-existent timer %d", timer);
}
/*
* Unregister a callback for a timer
* NB, it *must* be safe to call this from within a callback
* For this reason we only ever set a flag in the existing list.
* Actual deletion will be done out-of-band
*/
int virEventPollRemoveTimeout(int timer)
{
size_t i;
PROBE(EVENT_POLL_REMOVE_TIMEOUT,
"timer=%d",
timer);
if (timer <= 0) {
VIR_WARN("Ignoring invalid remove timer %d", timer);
return -1;
}
virMutexLock(&eventLoop.lock);
for (i = 0; i < eventLoop.timeoutsCount; i++) {
if (eventLoop.timeouts[i].deleted)
continue;
if (eventLoop.timeouts[i].timer == timer) {
eventLoop.timeouts[i].deleted = 1;
virEventPollInterruptLocked();
virMutexUnlock(&eventLoop.lock);
return 0;
}
}
virMutexUnlock(&eventLoop.lock);
return -1;
}
/* Iterates over all registered timeouts and determine which
* will be the first to expire.
* @timeout: filled with expiry time of soonest timer, or -1 if
* no timeout is pending
* returns: 0 on success, -1 on error
*/
static int virEventPollCalculateTimeout(int *timeout)
{
unsigned long long then = 0;
size_t i;
EVENT_DEBUG("Calculate expiry of %zu timers", eventLoop.timeoutsCount);
/* Figure out if we need a timeout */
for (i = 0; i < eventLoop.timeoutsCount; i++) {
if (eventLoop.timeouts[i].deleted)
continue;
if (eventLoop.timeouts[i].frequency < 0)
continue;
EVENT_DEBUG("Got a timeout scheduled for %llu", eventLoop.timeouts[i].expiresAt);
if (then == 0 ||
eventLoop.timeouts[i].expiresAt < then)
then = eventLoop.timeouts[i].expiresAt;
}
/* Calculate how long we should wait for a timeout if needed */
if (then > 0) {
unsigned long long now;
if (virTimeMillisNow(&now) < 0)
return -1;
EVENT_DEBUG("Schedule timeout then=%llu now=%llu", then, now);
if (then <= now)
*timeout = 0;
else
*timeout = ((then - now) > INT_MAX) ? INT_MAX : (then - now);
} else {
*timeout = -1;
}
if (*timeout > -1)
EVENT_DEBUG("Timeout at %llu due in %d ms", then, *timeout);
else
EVENT_DEBUG("%s", "No timeout is pending");
return 0;
}
/*
* Allocate a pollfd array containing data for all registered
* file handles. The caller must free the returned data struct
* returns: the pollfd array, or NULL on error
*/
static struct pollfd *virEventPollMakePollFDs(int *nfds) {
struct pollfd *fds;
size_t i;
*nfds = 0;
for (i = 0; i < eventLoop.handlesCount; i++) {
if (eventLoop.handles[i].events && !eventLoop.handles[i].deleted)
(*nfds)++;
}
/* Setup the poll file handle data structs */
if (VIR_ALLOC_N(fds, *nfds) < 0)
return NULL;
*nfds = 0;
for (i = 0; i < eventLoop.handlesCount; i++) {
EVENT_DEBUG("Prepare n=%zu w=%d, f=%d e=%d d=%d", i,
eventLoop.handles[i].watch,
eventLoop.handles[i].fd,
eventLoop.handles[i].events,
eventLoop.handles[i].deleted);
if (!eventLoop.handles[i].events || eventLoop.handles[i].deleted)
continue;
fds[*nfds].fd = eventLoop.handles[i].fd;
fds[*nfds].events = eventLoop.handles[i].events;
fds[*nfds].revents = 0;
(*nfds)++;
}
return fds;
}
/*
* Iterate over all timers and determine if any have expired.
* Invoke the user supplied callback for each timer whose
* expiry time is met, and schedule the next timeout. Does
* not try to 'catch up' on time if the actual expiry time
* was later than the requested time.
*
* This method must cope with new timers being registered
* by a callback, and must skip any timers marked as deleted.
*
* Returns 0 upon success, -1 if an error occurred
*/
static int virEventPollDispatchTimeouts(void)
{
unsigned long long now;
size_t i;
/* Save this now - it may be changed during dispatch */
int ntimeouts = eventLoop.timeoutsCount;
VIR_DEBUG("Dispatch %d", ntimeouts);
if (virTimeMillisNow(&now) < 0)
return -1;
for (i = 0; i < ntimeouts; i++) {
if (eventLoop.timeouts[i].deleted || eventLoop.timeouts[i].frequency < 0)
continue;
/* Add 20ms fuzz so we don't pointlessly spin doing
* <10ms sleeps, particularly on kernels with low HZ
* it is fine that a timer expires 20ms earlier than
* requested
*/
if (eventLoop.timeouts[i].expiresAt <= (now+20)) {
virEventTimeoutCallback cb = eventLoop.timeouts[i].cb;
int timer = eventLoop.timeouts[i].timer;
void *opaque = eventLoop.timeouts[i].opaque;
eventLoop.timeouts[i].expiresAt =
now + eventLoop.timeouts[i].frequency;
PROBE(EVENT_POLL_DISPATCH_TIMEOUT,
"timer=%d",
timer);
virMutexUnlock(&eventLoop.lock);
(cb)(timer, opaque);
virMutexLock(&eventLoop.lock);
}
}
return 0;
}
/* Iterate over all file handles and dispatch any which
* have pending events listed in the poll() data. Invoke
* the user supplied callback for each handle which has
* pending events
*
* This method must cope with new handles being registered
* by a callback, and must skip any handles marked as deleted.
*
* Returns 0 upon success, -1 if an error occurred
*/
static int virEventPollDispatchHandles(int nfds, struct pollfd *fds)
{
size_t i, n;
VIR_DEBUG("Dispatch %d", nfds);
/* NB, use nfds not eventLoop.handlesCount, because new
* fds might be added on end of list, and they're not
* in the fds array we've got */
for (i = 0, n = 0; n < nfds && i < eventLoop.handlesCount; n++) {
while (i < eventLoop.handlesCount &&
(eventLoop.handles[i].fd != fds[n].fd ||
eventLoop.handles[i].events == 0)) {
i++;
}
if (i == eventLoop.handlesCount)
break;
VIR_DEBUG("i=%zu w=%d", i, eventLoop.handles[i].watch);
if (eventLoop.handles[i].deleted) {
EVENT_DEBUG("Skip deleted n=%zu w=%d f=%d", i,
eventLoop.handles[i].watch, eventLoop.handles[i].fd);
continue;
}
if (fds[n].revents) {
virEventHandleCallback cb = eventLoop.handles[i].cb;
int watch = eventLoop.handles[i].watch;
void *opaque = eventLoop.handles[i].opaque;
int hEvents = virEventPollFromNativeEvents(fds[n].revents);
PROBE(EVENT_POLL_DISPATCH_HANDLE,
"watch=%d events=%d",
watch, hEvents);
virMutexUnlock(&eventLoop.lock);
(cb)(watch, fds[n].fd, hEvents, opaque);
virMutexLock(&eventLoop.lock);
}
}
return 0;
}
/* Used post dispatch to actually remove any timers that
* were previously marked as deleted. This asynchronous
* cleanup is needed to make dispatch re-entrant safe.
*/
static void virEventPollCleanupTimeouts(void)
{
size_t i;
size_t gap;
VIR_DEBUG("Cleanup %zu", eventLoop.timeoutsCount);
/* Remove deleted entries, shuffling down remaining
* entries as needed to form contiguous series
*/
for (i = 0; i < eventLoop.timeoutsCount;) {
if (!eventLoop.timeouts[i].deleted) {
i++;
continue;
}
PROBE(EVENT_POLL_PURGE_TIMEOUT,
"timer=%d",
eventLoop.timeouts[i].timer);
if (eventLoop.timeouts[i].ff) {
virFreeCallback ff = eventLoop.timeouts[i].ff;
void *opaque = eventLoop.timeouts[i].opaque;
virMutexUnlock(&eventLoop.lock);
ff(opaque);
virMutexLock(&eventLoop.lock);
}
if ((i+1) < eventLoop.timeoutsCount) {
size_t count = eventLoop.timeoutsCount - (i+1);
memmove(eventLoop.timeouts+i,
eventLoop.timeouts+i+1,
sizeof(struct virEventPollTimeout)*count);
}
eventLoop.timeoutsCount--;
}
/* Release some memory if we've got a big chunk free */
gap = eventLoop.timeoutsAlloc - eventLoop.timeoutsCount;
if (eventLoop.timeoutsCount == 0 ||
(gap > eventLoop.timeoutsCount && gap > EVENT_ALLOC_EXTENT)) {
EVENT_DEBUG("Found %zu out of %zu timeout slots used, releasing %zu",
eventLoop.timeoutsCount, eventLoop.timeoutsAlloc, gap);
VIR_SHRINK_N(eventLoop.timeouts, eventLoop.timeoutsAlloc, gap);
}
}
/* Used post dispatch to actually remove any handles that
* were previously marked as deleted. This asynchronous
* cleanup is needed to make dispatch re-entrant safe.
*/
static void virEventPollCleanupHandles(void)
{
size_t i;
size_t gap;
VIR_DEBUG("Cleanup %zu", eventLoop.handlesCount);
/* Remove deleted entries, shuffling down remaining
* entries as needed to form contiguous series
*/
for (i = 0; i < eventLoop.handlesCount;) {
if (!eventLoop.handles[i].deleted) {
i++;
continue;
}
PROBE(EVENT_POLL_PURGE_HANDLE,
"watch=%d",
eventLoop.handles[i].watch);
if (eventLoop.handles[i].ff) {
virFreeCallback ff = eventLoop.handles[i].ff;
void *opaque = eventLoop.handles[i].opaque;
virMutexUnlock(&eventLoop.lock);
ff(opaque);
virMutexLock(&eventLoop.lock);
}
if ((i+1) < eventLoop.handlesCount) {
size_t count = eventLoop.handlesCount - (i+1);
memmove(eventLoop.handles+i,
eventLoop.handles+i+1,
sizeof(struct virEventPollHandle)*count);
}
eventLoop.handlesCount--;
}
/* Release some memory if we've got a big chunk free */
gap = eventLoop.handlesAlloc - eventLoop.handlesCount;
if (eventLoop.handlesCount == 0 ||
(gap > eventLoop.handlesCount && gap > EVENT_ALLOC_EXTENT)) {
EVENT_DEBUG("Found %zu out of %zu handles slots used, releasing %zu",
eventLoop.handlesCount, eventLoop.handlesAlloc, gap);
VIR_SHRINK_N(eventLoop.handles, eventLoop.handlesAlloc, gap);
}
}
/*
* Run a single iteration of the event loop, blocking until
* at least one file handle has an event, or a timer expires
*/
int virEventPollRunOnce(void)
{
g_autofree struct pollfd *fds = NULL;
int ret, timeout, nfds;
virMutexLock(&eventLoop.lock);
eventLoop.running = 1;
virThreadSelf(&eventLoop.leader);
virEventPollCleanupTimeouts();
virEventPollCleanupHandles();
if (!(fds = virEventPollMakePollFDs(&nfds)) ||
virEventPollCalculateTimeout(&timeout) < 0)
goto error;
virMutexUnlock(&eventLoop.lock);
retry:
PROBE(EVENT_POLL_RUN,
"nhandles=%d timeout=%d",
nfds, timeout);
ret = poll(fds, nfds, timeout);
if (ret < 0) {
EVENT_DEBUG("Poll got error event %d", errno);
if (errno == EINTR || errno == EAGAIN)
goto retry;
#ifdef __APPLE__
if (errno == EBADF) {
virMutexLock(&eventLoop.lock);
goto cleanup;
}
#endif
virReportSystemError(errno, "%s",
_("Unable to poll on file handles"));
return -1;
}
EVENT_DEBUG("Poll got %d event(s)", ret);
virMutexLock(&eventLoop.lock);
if (virEventPollDispatchTimeouts() < 0)
goto error;
if (ret > 0 &&
virEventPollDispatchHandles(nfds, fds) < 0)
goto error;
virEventPollCleanupTimeouts();
virEventPollCleanupHandles();
#ifdef __APPLE__
cleanup:
#endif
eventLoop.running = 0;
virMutexUnlock(&eventLoop.lock);
return 0;
error:
virMutexUnlock(&eventLoop.lock);
return -1;
}
static void virEventPollHandleWakeup(int watch G_GNUC_UNUSED,
int fd,
int events G_GNUC_UNUSED,
void *opaque G_GNUC_UNUSED)
{
char c;
virMutexLock(&eventLoop.lock);
ignore_value(saferead(fd, &c, sizeof(c)));
virMutexUnlock(&eventLoop.lock);
}
int virEventPollInit(void)
{
if (virMutexInit(&eventLoop.lock) < 0) {
virReportSystemError(errno, "%s",
_("Unable to initialize mutex"));
return -1;
}
if (pipe2(eventLoop.wakeupfd, O_CLOEXEC | O_NONBLOCK) < 0) {
virReportSystemError(errno, "%s",
_("Unable to setup wakeup pipe"));
return -1;
}
if (virEventPollAddHandle(eventLoop.wakeupfd[0],
VIR_EVENT_HANDLE_READABLE,
virEventPollHandleWakeup, NULL, NULL) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Unable to add handle %d to event loop"),
eventLoop.wakeupfd[0]);
VIR_FORCE_CLOSE(eventLoop.wakeupfd[0]);
VIR_FORCE_CLOSE(eventLoop.wakeupfd[1]);
return -1;
}
return 0;
}
static int virEventPollInterruptLocked(void)
{
char c = '\0';
if (!eventLoop.running ||
virThreadIsSelf(&eventLoop.leader)) {
VIR_DEBUG("Skip interrupt, %d %llu", eventLoop.running,
virThreadID(&eventLoop.leader));
return 0;
}
VIR_DEBUG("Interrupting");
if (safewrite(eventLoop.wakeupfd[1], &c, sizeof(c)) != sizeof(c))
return -1;
return 0;
}
int virEventPollInterrupt(void)
{
int ret;
virMutexLock(&eventLoop.lock);
ret = virEventPollInterruptLocked();
virMutexUnlock(&eventLoop.lock);
return ret;
}
int
virEventPollToNativeEvents(int events)
{
int ret = 0;
if (events & VIR_EVENT_HANDLE_READABLE)
ret |= POLLIN;
if (events & VIR_EVENT_HANDLE_WRITABLE)
ret |= POLLOUT;
if (events & VIR_EVENT_HANDLE_ERROR)
ret |= POLLERR;
if (events & VIR_EVENT_HANDLE_HANGUP)
ret |= POLLHUP;
return ret;
}
int
virEventPollFromNativeEvents(int events)
{
int ret = 0;
if (events & POLLIN)
ret |= VIR_EVENT_HANDLE_READABLE;
if (events & POLLOUT)
ret |= VIR_EVENT_HANDLE_WRITABLE;
if (events & POLLERR)
ret |= VIR_EVENT_HANDLE_ERROR;
if (events & POLLNVAL) /* Treat NVAL as error, since libvirt doesn't distinguish */
ret |= VIR_EVENT_HANDLE_ERROR;
if (events & POLLHUP)
ret |= VIR_EVENT_HANDLE_HANGUP;
return ret;
}

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@ -1,126 +0,0 @@
/*
* vireventpoll.h: Poll based event loop for monitoring file handles
*
* Copyright (C) 2007 Daniel P. Berrange
* Copyright (C) 2007 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*/
#pragma once
#include "internal.h"
/**
* virEventPollAddHandle: register a callback for monitoring file handle events
*
* @fd: file handle to monitor for events
* @events: bitset of events to watch from POLLnnn constants
* @cb: callback to invoke when an event occurs
* @opaque: user data to pass to callback
*
* returns -1 if the file handle cannot be registered, 0 upon success
*/
int virEventPollAddHandle(int fd, int events,
virEventHandleCallback cb,
void *opaque,
virFreeCallback ff);
/**
* virEventPollUpdateHandle: change event set for a monitored file handle
*
* @watch: watch whose handle to update
* @events: bitset of events to watch from POLLnnn constants
*
* Will not fail if fd exists
*/
void virEventPollUpdateHandle(int watch, int events);
/**
* virEventPollRemoveHandle: unregister a callback from a file handle
*
* @watch: watch whose handle to remove
*
* returns -1 if the file handle was not registered, 0 upon success
*/
int virEventPollRemoveHandle(int watch);
/**
* virEventPollAddTimeout: register a callback for a timer event
*
* @frequency: time between events in milliseconds
* @cb: callback to invoke when an event occurs
* @opaque: user data to pass to callback
*
* Setting frequency to -1 will disable the timer. Setting the frequency
* to zero will cause it to fire on every event loop iteration.
*
* returns -1 if the file handle cannot be registered, a positive
* integer timer id upon success
*/
int virEventPollAddTimeout(int frequency,
virEventTimeoutCallback cb,
void *opaque,
virFreeCallback ff);
/**
* virEventPollUpdateTimeout: change frequency for a timer
*
* @timer: timer id to change
* @frequency: time between events in milliseconds
*
* Setting frequency to -1 will disable the timer. Setting the frequency
* to zero will cause it to fire on every event loop iteration.
*
* Will not fail if timer exists
*/
void virEventPollUpdateTimeout(int timer, int frequency);
/**
* virEventPollRemoveTimeout: unregister a callback for a timer
*
* @timer: the timer id to remove
*
* returns -1 if the timer was not registered, 0 upon success
*/
int virEventPollRemoveTimeout(int timer);
/**
* virEventPollInit: Initialize the event loop
*
* returns -1 if initialization failed
*/
int virEventPollInit(void);
/**
* virEventPollRunOnce: run a single iteration of the event loop.
*
* Blocks the caller until at least one file handle has an
* event or the first timer expires.
*
* returns -1 if the event monitoring failed
*/
int virEventPollRunOnce(void);
int virEventPollFromNativeEvents(int events);
int virEventPollToNativeEvents(int events);
/**
* virEventPollInterrupt: wakeup any thread waiting in poll()
*
* return -1 if wakeup failed
*/
int virEventPollInterrupt(void);