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authorLouai Al-Khanji <louai.al-khanji@theqtcompany.com>2015-10-16 16:19:53 +0300
committerLouai Al-Khanji <louai.al-khanji@theqtcompany.com>2016-01-26 19:41:45 +0000
commitacbd79996d7dedd65cda98bd1b0f15690f0271e4 (patch)
treef0a2848e7403cda397f0ee11679d11ab5a5f3fa9 /src
parentf3060312c89344744832e3352fe4f53efcb94c9b (diff)
QEventDispatcherUNIX: Use poll instead of select
This allows us to support file descriptors >= FD_SETSIZE. Change-Id: I7e4a35333446a587cfd13c077fa5e19fa3d1abc4 Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Diffstat (limited to 'src')
-rw-r--r--src/corelib/kernel/qeventdispatcher_unix.cpp440
-rw-r--r--src/corelib/kernel/qeventdispatcher_unix_p.h90
2 files changed, 206 insertions, 324 deletions
diff --git a/src/corelib/kernel/qeventdispatcher_unix.cpp b/src/corelib/kernel/qeventdispatcher_unix.cpp
index 87478e0e01..7fd18dc9c1 100644
--- a/src/corelib/kernel/qeventdispatcher_unix.cpp
+++ b/src/corelib/kernel/qeventdispatcher_unix.cpp
@@ -66,7 +66,7 @@
# define _POSIX_MONOTONIC_CLOCK 1
# endif
# include <pipeDrv.h>
-# include <selectLib.h>
+# include <sys/time.h>
#endif
#if (_POSIX_MONOTONIC_CLOCK-0 <= 0) || defined(QT_BOOTSTRAPPED)
@@ -75,6 +75,26 @@
QT_BEGIN_NAMESPACE
+static const char *socketType(QSocketNotifier::Type type)
+{
+ switch (type) {
+ case QSocketNotifier::Read:
+ return "Read";
+ case QSocketNotifier::Write:
+ return "Write";
+ case QSocketNotifier::Exception:
+ return "Exception";
+ }
+
+ Q_UNREACHABLE();
+}
+
+static pollfd make_pollfd(int fd, short events)
+{
+ pollfd pfd = { fd, events, 0 };
+ return pfd;
+}
+
#if defined(Q_OS_VXWORKS)
static void initThreadPipeFD(int fd)
{
@@ -133,8 +153,6 @@ QEventDispatcherUNIXPrivate::QEventDispatcherUNIXPrivate()
if (Q_UNLIKELY(pipefail))
qFatal("QEventDispatcherUNIXPrivate(): Can not continue without a thread pipe");
-
- sn_highest = -1;
}
QEventDispatcherUNIXPrivate::~QEventDispatcherUNIXPrivate()
@@ -159,116 +177,11 @@ QEventDispatcherUNIXPrivate::~QEventDispatcherUNIXPrivate()
qDeleteAll(timerList);
}
-int QEventDispatcherUNIXPrivate::doSelect(QEventLoop::ProcessEventsFlags flags, timespec *timeout)
-{
- Q_Q(QEventDispatcherUNIX);
-
- // needed in QEventDispatcherUNIX::select()
- timerList.updateCurrentTime();
-
- int nsel;
- do {
- // Process timers and socket notifiers - the common UNIX stuff
- int highest = 0;
- if (! (flags & QEventLoop::ExcludeSocketNotifiers) && (sn_highest >= 0)) {
- // return the highest fd we can wait for input on
- sn_vec[0].select_fds = sn_vec[0].enabled_fds;
- sn_vec[1].select_fds = sn_vec[1].enabled_fds;
- sn_vec[2].select_fds = sn_vec[2].enabled_fds;
- highest = sn_highest;
- } else {
- FD_ZERO(&sn_vec[0].select_fds);
- FD_ZERO(&sn_vec[1].select_fds);
- FD_ZERO(&sn_vec[2].select_fds);
- }
-
- int wakeUpFd = initThreadWakeUp();
- highest = qMax(highest, wakeUpFd);
-
- nsel = q->select(highest + 1,
- &sn_vec[0].select_fds,
- &sn_vec[1].select_fds,
- &sn_vec[2].select_fds,
- timeout);
- } while (nsel == -1 && (errno == EINTR || errno == EAGAIN));
-
- if (nsel == -1) {
- if (errno == EBADF) {
- // it seems a socket notifier has a bad fd... find out
- // which one it is and disable it
- fd_set fdset;
- timeval tm;
- tm.tv_sec = tm.tv_usec = 0l;
-
- for (int type = 0; type < 3; ++type) {
- QSockNotType::List &list = sn_vec[type].list;
- if (list.size() == 0)
- continue;
-
- for (int i = 0; i < list.size(); ++i) {
- QSockNot *sn = list[i];
-
- FD_ZERO(&fdset);
- FD_SET(sn->fd, &fdset);
-
- int ret = -1;
- do {
- switch (type) {
- case 0: // read
- ret = select(sn->fd + 1, &fdset, 0, 0, &tm);
- break;
- case 1: // write
- ret = select(sn->fd + 1, 0, &fdset, 0, &tm);
- break;
- case 2: // except
- ret = select(sn->fd + 1, 0, 0, &fdset, &tm);
- break;
- }
- } while (ret == -1 && (errno == EINTR || errno == EAGAIN));
-
- if (ret == -1 && errno == EBADF) {
- // disable the invalid socket notifier
- static const char *t[] = { "Read", "Write", "Exception" };
- qWarning("QSocketNotifier: Invalid socket %d and type '%s', disabling...",
- sn->fd, t[type]);
- sn->obj->setEnabled(false);
- }
- }
- }
- } else {
- // EINVAL... shouldn't happen, so let's complain to stderr
- // and hope someone sends us a bug report
- perror("select");
- }
- }
-
- int nevents = processThreadWakeUp(nsel);
-
- // activate socket notifiers
- if (! (flags & QEventLoop::ExcludeSocketNotifiers) && nsel > 0 && sn_highest >= 0) {
- // if select says data is ready on any socket, then set the socket notifier
- // to pending
- for (int i=0; i<3; i++) {
- QSockNotType::List &list = sn_vec[i].list;
- for (int j = 0; j < list.size(); ++j) {
- QSockNot *sn = list[j];
- if (FD_ISSET(sn->fd, &sn_vec[i].select_fds))
- q->setSocketNotifierPending(sn->obj);
- }
- }
- }
- return (nevents + q->activateSocketNotifiers());
-}
-
-int QEventDispatcherUNIXPrivate::initThreadWakeUp()
+int QEventDispatcherUNIXPrivate::processThreadWakeUp(const pollfd &pfd)
{
- FD_SET(thread_pipe[0], &sn_vec[0].select_fds);
- return thread_pipe[0];
-}
+ Q_ASSERT(pfd.fd == thread_pipe[0]);
-int QEventDispatcherUNIXPrivate::processThreadWakeUp(int nsel)
-{
- if (nsel > 0 && FD_ISSET(thread_pipe[0], &sn_vec[0].select_fds)) {
+ if (pfd.revents & POLLIN) {
// some other thread woke us up... consume the data on the thread pipe so that
// select doesn't immediately return next time
#if defined(Q_OS_VXWORKS)
@@ -298,6 +211,80 @@ int QEventDispatcherUNIXPrivate::processThreadWakeUp(int nsel)
return 0;
}
+void QEventDispatcherUNIXPrivate::setSocketNotifierPending(QSocketNotifier *notifier)
+{
+ Q_ASSERT(notifier);
+
+ if (pendingNotifiers.contains(notifier))
+ return;
+
+ pendingNotifiers << notifier;
+}
+
+int QEventDispatcherUNIXPrivate::activateTimers()
+{
+ return timerList.activateTimers();
+}
+
+void QEventDispatcherUNIXPrivate::markPendingSocketNotifiers()
+{
+ for (const pollfd &pfd : qAsConst(pollfds)) {
+ if (pfd.fd < 0 || pfd.revents == 0)
+ continue;
+
+ auto it = socketNotifiers.find(pfd.fd);
+ Q_ASSERT(it != socketNotifiers.end());
+
+ const QSocketNotifierSetUNIX &sn_set = it.value();
+
+ static const struct {
+ QSocketNotifier::Type type;
+ short flags;
+ } notifiers[] = {
+ { QSocketNotifier::Read, POLLIN | POLLHUP | POLLERR },
+ { QSocketNotifier::Write, POLLOUT | POLLHUP | POLLERR },
+ { QSocketNotifier::Exception, POLLPRI | POLLHUP | POLLERR }
+ };
+
+ for (const auto &n : notifiers) {
+ QSocketNotifier *notifier = sn_set.notifiers[n.type];
+
+ if (!notifier)
+ continue;
+
+ if (pfd.revents & POLLNVAL) {
+ qWarning("QSocketNotifier: Invalid socket %d with type %s, disabling...",
+ it.key(), socketType(n.type));
+ notifier->setEnabled(false);
+ }
+
+ if (pfd.revents & n.flags)
+ setSocketNotifierPending(notifier);
+ }
+ }
+
+ pollfds.resize(0);
+}
+
+int QEventDispatcherUNIXPrivate::activateSocketNotifiers()
+{
+ markPendingSocketNotifiers();
+
+ if (pendingNotifiers.isEmpty())
+ return 0;
+
+ int n_activated = 0;
+ QEvent event(QEvent::SockAct);
+
+ while (!pendingNotifiers.isEmpty()) {
+ QSocketNotifier *notifier = pendingNotifiers.takeFirst();
+ QCoreApplication::sendEvent(notifier, &event);
+ ++n_activated;
+ }
+
+ return n_activated;
+}
+
QEventDispatcherUNIX::QEventDispatcherUNIX(QObject *parent)
: QAbstractEventDispatcher(*new QEventDispatcherUNIXPrivate, parent)
{ }
@@ -307,14 +294,7 @@ QEventDispatcherUNIX::QEventDispatcherUNIX(QEventDispatcherUNIXPrivate &dd, QObj
{ }
QEventDispatcherUNIX::~QEventDispatcherUNIX()
-{
-}
-
-int QEventDispatcherUNIX::select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
- timespec *timeout)
-{
- return qt_safe_select(nfds, readfds, writefds, exceptfds, timeout);
-}
+{ }
/*!
\internal
@@ -386,22 +366,6 @@ QEventDispatcherUNIX::registeredTimers(QObject *object) const
}
/*****************************************************************************
- Socket notifier type
- *****************************************************************************/
-QSockNotType::QSockNotType()
-{
- FD_ZERO(&select_fds);
- FD_ZERO(&enabled_fds);
- FD_ZERO(&pending_fds);
-}
-
-QSockNotType::~QSockNotType()
-{
- for (int i = 0; i < list.size(); ++i)
- delete list[i];
-}
-
-/*****************************************************************************
QEventDispatcher implementations for UNIX
*****************************************************************************/
@@ -409,160 +373,59 @@ void QEventDispatcherUNIX::registerSocketNotifier(QSocketNotifier *notifier)
{
Q_ASSERT(notifier);
int sockfd = notifier->socket();
- int type = notifier->type();
+ QSocketNotifier::Type type = notifier->type();
#ifndef QT_NO_DEBUG
- if (sockfd < 0
- || unsigned(sockfd) >= FD_SETSIZE) {
- qWarning("QSocketNotifier: Internal error");
- return;
- } else if (notifier->thread() != thread()
- || thread() != QThread::currentThread()) {
+ if (notifier->thread() != thread() || thread() != QThread::currentThread()) {
qWarning("QSocketNotifier: socket notifiers cannot be enabled from another thread");
return;
}
#endif
Q_D(QEventDispatcherUNIX);
- QSockNotType::List &list = d->sn_vec[type].list;
- fd_set *fds = &d->sn_vec[type].enabled_fds;
- QSockNot *sn;
-
- sn = new QSockNot;
- sn->obj = notifier;
- sn->fd = sockfd;
- sn->queue = &d->sn_vec[type].pending_fds;
-
- int i;
- for (i = 0; i < list.size(); ++i) {
- QSockNot *p = list[i];
- if (p->fd < sockfd)
- break;
- if (p->fd == sockfd) {
- static const char *t[] = { "Read", "Write", "Exception" };
- qWarning("QSocketNotifier: Multiple socket notifiers for "
- "same socket %d and type %s", sockfd, t[type]);
- }
- }
- list.insert(i, sn);
+ QSocketNotifierSetUNIX &sn_set = d->socketNotifiers[sockfd];
- FD_SET(sockfd, fds);
- d->sn_highest = qMax(d->sn_highest, sockfd);
+ if (sn_set.notifiers[type] && sn_set.notifiers[type] != notifier)
+ qWarning("%s: Multiple socket notifiers for same socket %d and type %s",
+ Q_FUNC_INFO, sockfd, socketType(type));
+
+ sn_set.notifiers[type] = notifier;
}
void QEventDispatcherUNIX::unregisterSocketNotifier(QSocketNotifier *notifier)
{
Q_ASSERT(notifier);
int sockfd = notifier->socket();
- int type = notifier->type();
+ QSocketNotifier::Type type = notifier->type();
#ifndef QT_NO_DEBUG
- if (sockfd < 0
- || unsigned(sockfd) >= FD_SETSIZE) {
- qWarning("QSocketNotifier: Internal error");
- return;
- } else if (notifier->thread() != thread()
- || thread() != QThread::currentThread()) {
+ if (notifier->thread() != thread() || thread() != QThread::currentThread()) {
qWarning("QSocketNotifier: socket notifiers cannot be disabled from another thread");
return;
}
#endif
Q_D(QEventDispatcherUNIX);
- QSockNotType::List &list = d->sn_vec[type].list;
- fd_set *fds = &d->sn_vec[type].enabled_fds;
- QSockNot *sn = 0;
- int i;
- for (i = 0; i < list.size(); ++i) {
- sn = list[i];
- if(sn->obj == notifier && sn->fd == sockfd)
- break;
- }
- if (i == list.size()) // not found
- return;
- FD_CLR(sockfd, fds); // clear fd bit
- FD_CLR(sockfd, sn->queue);
- d->sn_pending_list.removeAll(sn); // remove from activation list
- list.removeAt(i); // remove notifier found above
- delete sn;
-
- if (d->sn_highest == sockfd) { // find highest fd
- d->sn_highest = -1;
- for (int i=0; i<3; i++) {
- if (!d->sn_vec[i].list.isEmpty())
- d->sn_highest = qMax(d->sn_highest, // list is fd-sorted
- d->sn_vec[i].list[0]->fd);
- }
- }
-}
+ d->pendingNotifiers.removeOne(notifier);
-void QEventDispatcherUNIX::setSocketNotifierPending(QSocketNotifier *notifier)
-{
- Q_ASSERT(notifier);
- int sockfd = notifier->socket();
- int type = notifier->type();
-#ifndef QT_NO_DEBUG
- if (sockfd < 0
- || unsigned(sockfd) >= FD_SETSIZE) {
- qWarning("QSocketNotifier: Internal error");
+ auto i = d->socketNotifiers.find(sockfd);
+ if (i == d->socketNotifiers.end())
return;
- }
- Q_ASSERT(notifier->thread() == thread() && thread() == QThread::currentThread());
-#endif
- Q_D(QEventDispatcherUNIX);
- QSockNotType::List &list = d->sn_vec[type].list;
- QSockNot *sn = 0;
- int i;
- for (i = 0; i < list.size(); ++i) {
- sn = list[i];
- if(sn->obj == notifier && sn->fd == sockfd)
- break;
- }
- if (i == list.size()) // not found
+ QSocketNotifierSetUNIX &sn_set = i.value();
+
+ if (sn_set.notifiers[type] == nullptr)
return;
- // We choose a random activation order to be more fair under high load.
- // If a constant order is used and a peer early in the list can
- // saturate the IO, it might grab our attention completely.
- // Also, if we're using a straight list, the callback routines may
- // delete other entries from the list before those other entries are
- // processed.
- if (! FD_ISSET(sn->fd, sn->queue)) {
- if (d->sn_pending_list.isEmpty()) {
- d->sn_pending_list.append(sn);
- } else {
- d->sn_pending_list.insert((qrand() & 0xff) %
- (d->sn_pending_list.size()+1), sn);
- }
- FD_SET(sn->fd, sn->queue);
+ if (sn_set.notifiers[type] != notifier) {
+ qWarning("%s: Multiple socket notifiers for same socket %d and type %s",
+ Q_FUNC_INFO, sockfd, socketType(type));
+ return;
}
-}
-
-int QEventDispatcherUNIX::activateTimers()
-{
- Q_ASSERT(thread() == QThread::currentThread());
- Q_D(QEventDispatcherUNIX);
- return d->timerList.activateTimers();
-}
-int QEventDispatcherUNIX::activateSocketNotifiers()
-{
- Q_D(QEventDispatcherUNIX);
- if (d->sn_pending_list.isEmpty())
- return 0;
+ sn_set.notifiers[type] = nullptr;
- // activate entries
- int n_act = 0;
- QEvent event(QEvent::SockAct);
- while (!d->sn_pending_list.isEmpty()) {
- QSockNot *sn = d->sn_pending_list.takeFirst();
- if (FD_ISSET(sn->fd, sn->queue)) {
- FD_CLR(sn->fd, sn->queue);
- QCoreApplication::sendEvent(sn->obj, &event);
- ++n_act;
- }
- }
- return n_act;
+ if (sn_set.isEmpty())
+ d->socketNotifiers.erase(i);
}
bool QEventDispatcherUNIX::processEvents(QEventLoop::ProcessEventsFlags flags)
@@ -574,39 +437,54 @@ bool QEventDispatcherUNIX::processEvents(QEventLoop::ProcessEventsFlags flags)
emit awake();
QCoreApplicationPrivate::sendPostedEvents(0, 0, d->threadData);
- int nevents = 0;
+ const bool include_timers = (flags & QEventLoop::X11ExcludeTimers) == 0;
+ const bool include_notifiers = (flags & QEventLoop::ExcludeSocketNotifiers) == 0;
+ const bool wait_for_events = flags & QEventLoop::WaitForMoreEvents;
+
const bool canWait = (d->threadData->canWaitLocked()
&& !d->interrupt.load()
- && (flags & QEventLoop::WaitForMoreEvents));
+ && wait_for_events);
if (canWait)
emit aboutToBlock();
- if (!d->interrupt.load()) {
- // return the maximum time we can wait for an event.
- timespec *tm = 0;
- timespec wait_tm = { 0l, 0l };
- if (!(flags & QEventLoop::X11ExcludeTimers)) {
- if (d->timerList.timerWait(wait_tm))
- tm = &wait_tm;
- }
+ if (d->interrupt.load())
+ return false;
- if (!canWait) {
- if (!tm)
- tm = &wait_tm;
+ timespec *tm = nullptr;
+ timespec wait_tm = { 0, 0 };
- // no time to wait
- tm->tv_sec = 0l;
- tm->tv_nsec = 0l;
- }
+ if (!canWait || (include_timers && d->timerList.timerWait(wait_tm)))
+ tm = &wait_tm;
- nevents = d->doSelect(flags, tm);
+ d->pollfds.reserve(1 + (include_notifiers ? d->socketNotifiers.size() : 0));
+ d->pollfds.resize(0);
- // activate timers
- if (! (flags & QEventLoop::X11ExcludeTimers)) {
- nevents += activateTimers();
- }
+ if (include_notifiers)
+ for (auto it = d->socketNotifiers.cbegin(); it != d->socketNotifiers.cend(); ++it)
+ d->pollfds.append(make_pollfd(it.key(), it.value().events()));
+
+ // This must be last, as it's popped off the end below
+ d->pollfds.append(make_pollfd(d->thread_pipe[0], POLLIN));
+
+ int nevents = 0;
+
+ switch (qt_safe_poll(d->pollfds.data(), d->pollfds.size(), tm)) {
+ case -1:
+ perror("qt_safe_poll");
+ break;
+ case 0:
+ break;
+ default:
+ nevents += d->processThreadWakeUp(d->pollfds.takeLast());
+ if (include_notifiers)
+ nevents += d->activateSocketNotifiers();
+ break;
}
+
+ if (include_timers)
+ nevents += d->activateTimers();
+
// return true if we handled events, false otherwise
return (nevents > 0);
}
diff --git a/src/corelib/kernel/qeventdispatcher_unix_p.h b/src/corelib/kernel/qeventdispatcher_unix_p.h
index 0ed57d12f8..b401c07040 100644
--- a/src/corelib/kernel/qeventdispatcher_unix_p.h
+++ b/src/corelib/kernel/qeventdispatcher_unix_p.h
@@ -59,38 +59,22 @@
#include "QtCore/qvarlengtharray.h"
#include "private/qtimerinfo_unix_p.h"
-#if !defined(Q_OS_VXWORKS)
-# include <sys/time.h>
-# if (!defined(Q_OS_HPUX) || defined(__ia64)) && !defined(Q_OS_NACL)
-# include <sys/select.h>
-# endif
-#endif
-
QT_BEGIN_NAMESPACE
-struct QSockNot
-{
- QSocketNotifier *obj;
- int fd;
- fd_set *queue;
-};
+class QEventDispatcherUNIXPrivate;
-class QSockNotType
+struct Q_CORE_EXPORT QSocketNotifierSetUNIX Q_DECL_FINAL
{
-public:
- QSockNotType();
- ~QSockNotType();
-
- typedef QPodList<QSockNot*, 32> List;
+ inline QSocketNotifierSetUNIX() Q_DECL_NOTHROW;
- List list;
- fd_set select_fds;
- fd_set enabled_fds;
- fd_set pending_fds;
+ inline bool isEmpty() const Q_DECL_NOTHROW;
+ inline short events() const Q_DECL_NOTHROW;
+ QSocketNotifier *notifiers[3];
};
-class QEventDispatcherUNIXPrivate;
+Q_DECLARE_TYPEINFO(QSocketNotifierSetUNIX, Q_PRIMITIVE_TYPE);
+
class Q_CORE_EXPORT QEventDispatcherUNIX : public QAbstractEventDispatcher
{
@@ -120,15 +104,6 @@ public:
protected:
QEventDispatcherUNIX(QEventDispatcherUNIXPrivate &dd, QObject *parent = 0);
-
- void setSocketNotifierPending(QSocketNotifier *notifier);
-
- int activateTimers();
- int activateSocketNotifiers();
-
- virtual int select(int nfds,
- fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
- timespec *timeout);
};
class Q_CORE_EXPORT QEventDispatcherUNIXPrivate : public QAbstractEventDispatcherPrivate
@@ -139,28 +114,57 @@ public:
QEventDispatcherUNIXPrivate();
~QEventDispatcherUNIXPrivate();
- int doSelect(QEventLoop::ProcessEventsFlags flags, timespec *timeout);
- virtual int initThreadWakeUp() Q_DECL_FINAL;
- virtual int processThreadWakeUp(int nsel) Q_DECL_FINAL;
+ int processThreadWakeUp(const pollfd &pfd);
+
+ int activateTimers();
+
+ void markPendingSocketNotifiers();
+ int activateSocketNotifiers();
+ void setSocketNotifierPending(QSocketNotifier *notifier);
// note for eventfd(7) support:
// if thread_pipe[1] is -1, then eventfd(7) is in use and is stored in thread_pipe[0]
int thread_pipe[2];
- // highest fd for all socket notifiers
- int sn_highest;
- // 3 socket notifier types - read, write and exception
- QSockNotType sn_vec[3];
+ QVector<pollfd> pollfds;
- QTimerInfoList timerList;
+ QHash<int, QSocketNotifierSetUNIX> socketNotifiers;
+ QVector<QSocketNotifier *> pendingNotifiers;
- // pending socket notifiers list
- QSockNotType::List sn_pending_list;
+ QTimerInfoList timerList;
QAtomicInt wakeUps;
QAtomicInt interrupt; // bool
};
+inline QSocketNotifierSetUNIX::QSocketNotifierSetUNIX() Q_DECL_NOTHROW
+{
+ notifiers[0] = 0;
+ notifiers[1] = 0;
+ notifiers[2] = 0;
+}
+
+inline bool QSocketNotifierSetUNIX::isEmpty() const Q_DECL_NOTHROW
+{
+ return !notifiers[0] && !notifiers[1] && !notifiers[2];
+}
+
+inline short QSocketNotifierSetUNIX::events() const Q_DECL_NOTHROW
+{
+ short result = 0;
+
+ if (notifiers[0])
+ result |= POLLIN;
+
+ if (notifiers[1])
+ result |= POLLOUT;
+
+ if (notifiers[2])
+ result |= POLLPRI;
+
+ return result;
+}
+
QT_END_NAMESPACE
#endif // QEVENTDISPATCHER_UNIX_P_H