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commit 8a2d9073e959356808ce1685822b839d880e6498
Author: Florian Weimer <fweimer@redhat.com>
Date:   Fri Sep 14 17:27:35 2012 +0200

    Replace most calls to select(2) with poll(2)
    
    select(2) limits the number of file descriptor in a process to
    FD_SETSIZE (typically 1023).  Process creation and certain socket
    operations fail because they call select(2) on a file descriptor outside
    the FD_SETSIZE range.
    
    The remaining select(2) calls are used for timeouts only, or are in the
    traditional event loop.  The glib-based event loop does not use
    select(2), so this should be sufficient.
    
    This change adds a poll emulation for VxWorks, which only offers
    select(2).
    
    Change-Id: I9b0cf5bec81da70b29c501c62d14fb57df87fa61

diff --git a/src/corelib/io/qprocess_unix.cpp b/src/corelib/io/qprocess_unix.cpp
index e159bf8..bb8a3ae 100644
--- a/src/corelib/io/qprocess_unix.cpp
+++ b/src/corelib/io/qprocess_unix.cpp
@@ -134,13 +134,6 @@ static void qt_sa_sigchld_handler(int signum)
         oldAction(signum);
 }
 
-static inline void add_fd(int &nfds, int fd, fd_set *fdset)
-{
-    FD_SET(fd, fdset);
-    if ((fd) > nfds)
-        nfds = fd;
-}
-
 struct QProcessInfo {
     QProcess *process;
     int deathPipe;
@@ -235,9 +228,9 @@ QProcessManager::~QProcessManager()
 void QProcessManager::run()
 {
     forever {
-        fd_set readset;
-        FD_ZERO(&readset);
-        FD_SET(qt_qprocess_deadChild_pipe[0], &readset);
+	pollfd fd;
+	fd.fd = qt_qprocess_deadChild_pipe[0];
+	fd.events = POLLIN;
 
 #if defined (QPROCESS_DEBUG)
         qDebug() << "QProcessManager::run() waiting for children to die";
@@ -246,8 +239,8 @@ void QProcessManager::run()
         // block forever, or until activity is detected on the dead child
         // pipe. the only other peers are the SIGCHLD signal handler, and the
         // QProcessManager destructor.
-        int nselect = select(qt_qprocess_deadChild_pipe[0] + 1, &readset, 0, 0, 0);
-        if (nselect < 0) {
+        int ret = qt_safe_poll(&fd, 1, -1, /* retry_eintr */ false);
+        if (ret < 0) {
             if (errno == EINTR)
                 continue;
             break;
@@ -996,17 +989,6 @@ void QProcessPrivate::killProcess()
         ::kill(pid_t(pid), SIGKILL);
 }
 
-static int select_msecs(int nfds, fd_set *fdread, fd_set *fdwrite, int timeout)
-{
-    if (timeout < 0)
-        return qt_safe_select(nfds, fdread, fdwrite, 0, 0);
-
-    struct timeval tv;
-    tv.tv_sec = timeout / 1000;
-    tv.tv_usec = (timeout % 1000) * 1000;
-    return qt_safe_select(nfds, fdread, fdwrite, 0, &tv);
-}
-
 /*
    Returns the difference between msecs and elapsed. If msecs is -1,
    however, -1 is returned.
@@ -1029,10 +1011,10 @@ bool QProcessPrivate::waitForStarted(int msecs)
 	   childStartedPipe[0]);
 #endif
 
-    fd_set fds;
-    FD_ZERO(&fds);
-    FD_SET(childStartedPipe[0], &fds);
-    if (select_msecs(childStartedPipe[0] + 1, &fds, 0, msecs) == 0) {
+    pollfd fd;
+    fd.fd = childStartedPipe[0];
+    fd.events = POLLIN;
+    if (qt_safe_poll(&fd, 1, msecs) == 0) {
         processError = QProcess::Timedout;
         q->setErrorString(QProcess::tr("Process operation timed out"));
 #if defined (QPROCESS_DEBUG)
@@ -1048,6 +1030,47 @@ bool QProcessPrivate::waitForStarted(int msecs)
     return startedEmitted;
 }
 
+class QProcessFDSet {
+    pollfd fds[5];
+
+    static size_t size()
+    {
+	return sizeof(fds)/sizeof(fds[0]);
+    }
+
+public:
+    QProcessFDSet(QProcessPrivate &proc)
+    {
+	for (size_t i = 0; i < size(); ++i) {
+	    fds[i].fd = -1;
+	    fds[i].events = POLLIN;
+	}
+	death().fd = proc.deathPipe[0];
+
+        if (proc.processState == QProcess::Starting)
+	    started().fd = proc.childStartedPipe[0];
+
+	stdout().fd = proc.stdoutChannel.pipe[0];
+	stderr().fd = proc.stderrChannel.pipe[0];
+
+        if (!proc.writeBuffer.isEmpty()) {
+	    stdin().fd = proc.stdinChannel.pipe[1];
+	    stdin().events = POLLOUT;
+	}
+    }
+
+    int poll(int timeout)
+    {
+	return qt_safe_poll(fds, size(), timeout);
+    }
+
+    pollfd &death() { return fds[0]; }
+    pollfd &started() { return fds[1]; }
+    pollfd &stdout() { return fds[2]; }
+    pollfd &stderr() { return fds[3]; }
+    pollfd &stdin() { return fds[4]; }
+};
+
 bool QProcessPrivate::waitForReadyRead(int msecs)
 {
     Q_Q(QProcess);
@@ -1059,28 +1082,9 @@ bool QProcessPrivate::waitForReadyRead(int msecs)
     stopWatch.start();
 
     forever {
-        fd_set fdread;
-        fd_set fdwrite;
-
-        FD_ZERO(&fdread);
-        FD_ZERO(&fdwrite);
-
-        int nfds = deathPipe[0];
-        FD_SET(deathPipe[0], &fdread);
-
-        if (processState == QProcess::Starting)
-            add_fd(nfds, childStartedPipe[0], &fdread);
-
-        if (stdoutChannel.pipe[0] != -1)
-            add_fd(nfds, stdoutChannel.pipe[0], &fdread);
-        if (stderrChannel.pipe[0] != -1)
-            add_fd(nfds, stderrChannel.pipe[0], &fdread);
-
-        if (!writeBuffer.isEmpty() && stdinChannel.pipe[1] != -1)
-            add_fd(nfds, stdinChannel.pipe[1], &fdwrite);
-
+	QProcessFDSet fdset(*this);
         int timeout = qt_timeout_value(msecs, stopWatch.elapsed());
-        int ret = select_msecs(nfds + 1, &fdread, &fdwrite, timeout);
+        int ret = fdset.poll(timeout);
         if (ret < 0) {
             break;
         }
@@ -1090,18 +1094,18 @@ bool QProcessPrivate::waitForReadyRead(int msecs)
 	    return false;
 	}
 
-	if (childStartedPipe[0] != -1 && FD_ISSET(childStartedPipe[0], &fdread)) {
+	if (qt_readable(fdset.started())) {
             if (!_q_startupNotification())
                 return false;
 	}
 
         bool readyReadEmitted = false;
-	if (stdoutChannel.pipe[0] != -1 && FD_ISSET(stdoutChannel.pipe[0], &fdread)) {
+	if (qt_readable(fdset.stdout())) {
 	    bool canRead = _q_canReadStandardOutput();
             if (processChannel == QProcess::StandardOutput && canRead)
                 readyReadEmitted = true;
 	}
-	if (stderrChannel.pipe[0] != -1 && FD_ISSET(stderrChannel.pipe[0], &fdread)) {
+	if (qt_readable(fdset.stderr())) {
 	    bool canRead = _q_canReadStandardError();
             if (processChannel == QProcess::StandardError && canRead)
                 readyReadEmitted = true;
@@ -1109,13 +1113,13 @@ bool QProcessPrivate::waitForReadyRead(int msecs)
         if (readyReadEmitted)
             return true;
 
-	if (stdinChannel.pipe[1] != -1 && FD_ISSET(stdinChannel.pipe[1], &fdwrite))
+	if (qt_writable(fdset.stdin()))
 	    _q_canWrite();
 
-	if (deathPipe[0] == -1 || FD_ISSET(deathPipe[0], &fdread)) {
+	if (qt_readable(fdset.death())) {
             if (_q_processDied())
                 return false;
-        }
+	}
     }
     return false;
 }
@@ -1131,29 +1135,9 @@ bool QProcessPrivate::waitForBytesWritten(int msecs)
     stopWatch.start();
 
     while (!writeBuffer.isEmpty()) {
-        fd_set fdread;
-        fd_set fdwrite;
-
-        FD_ZERO(&fdread);
-        FD_ZERO(&fdwrite);
-
-        int nfds = deathPipe[0];
-        FD_SET(deathPipe[0], &fdread);
-
-        if (processState == QProcess::Starting)
-            add_fd(nfds, childStartedPipe[0], &fdread);
-
-        if (stdoutChannel.pipe[0] != -1)
-            add_fd(nfds, stdoutChannel.pipe[0], &fdread);
-        if (stderrChannel.pipe[0] != -1)
-            add_fd(nfds, stderrChannel.pipe[0], &fdread);
-
-
-        if (!writeBuffer.isEmpty() && stdinChannel.pipe[1] != -1)
-            add_fd(nfds, stdinChannel.pipe[1], &fdwrite);
-
+	QProcessFDSet fdset(*this);
 	int timeout = qt_timeout_value(msecs, stopWatch.elapsed());
-	int ret = select_msecs(nfds + 1, &fdread, &fdwrite, timeout);
+	int ret = fdset.poll(timeout);
         if (ret < 0) {
             break;
         }
@@ -1164,24 +1148,24 @@ bool QProcessPrivate::waitForBytesWritten(int msecs)
 	    return false;
 	}
 
-	if (childStartedPipe[0] != -1 && FD_ISSET(childStartedPipe[0], &fdread)) {
+	if (qt_readable(fdset.started())) {
 	    if (!_q_startupNotification())
 		return false;
 	}
 
-	if (stdinChannel.pipe[1] != -1 && FD_ISSET(stdinChannel.pipe[1], &fdwrite))
+	if (qt_writable(fdset.stdin()))
 	    return _q_canWrite();
 
-	if (stdoutChannel.pipe[0] != -1 && FD_ISSET(stdoutChannel.pipe[0], &fdread))
+	if (qt_readable(fdset.stdout()))
 	    _q_canReadStandardOutput();
 
-	if (stderrChannel.pipe[0] != -1 && FD_ISSET(stderrChannel.pipe[0], &fdread))
+	if (qt_readable(fdset.stderr()))
 	    _q_canReadStandardError();
 
-	if (deathPipe[0] == -1 || FD_ISSET(deathPipe[0], &fdread)) {
-            if (_q_processDied())
-                return false;
-        }
+	if (qt_readable(fdset.death())) {
+	    if (_q_processDied())
+		return false;
+	}
     }
 
     return false;
@@ -1198,29 +1182,9 @@ bool QProcessPrivate::waitForFinished(int msecs)
     stopWatch.start();
 
     forever {
-        fd_set fdread;
-        fd_set fdwrite;
-        int nfds = -1;
-
-        FD_ZERO(&fdread);
-        FD_ZERO(&fdwrite);
-
-        if (processState == QProcess::Starting)
-            add_fd(nfds, childStartedPipe[0], &fdread);
-
-        if (stdoutChannel.pipe[0] != -1)
-            add_fd(nfds, stdoutChannel.pipe[0], &fdread);
-        if (stderrChannel.pipe[0] != -1)
-            add_fd(nfds, stderrChannel.pipe[0], &fdread);
-
-        if (processState == QProcess::Running)
-            add_fd(nfds, deathPipe[0], &fdread);
-
-        if (!writeBuffer.isEmpty() && stdinChannel.pipe[1] != -1)
-            add_fd(nfds, stdinChannel.pipe[1], &fdwrite);
-
+	QProcessFDSet fdset(*this);
 	int timeout = qt_timeout_value(msecs, stopWatch.elapsed());
-	int ret = select_msecs(nfds + 1, &fdread, &fdwrite, timeout);
+	int ret = fdset.poll(timeout);
         if (ret < 0) {
             break;
         }
@@ -1230,20 +1194,20 @@ bool QProcessPrivate::waitForFinished(int msecs)
 	    return false;
 	}
 
-	if (childStartedPipe[0] != -1 && FD_ISSET(childStartedPipe[0], &fdread)) {
+	if (qt_readable(fdset.started())) {
 	    if (!_q_startupNotification())
 		return false;
 	}
-	if (stdinChannel.pipe[1] != -1 && FD_ISSET(stdinChannel.pipe[1], &fdwrite))
+	if (qt_writable(fdset.stdin()))
 	    _q_canWrite();
 
-	if (stdoutChannel.pipe[0] != -1 && FD_ISSET(stdoutChannel.pipe[0], &fdread))
+	if (qt_readable(fdset.stdout()))
 	    _q_canReadStandardOutput();
 
-	if (stderrChannel.pipe[0] != -1 && FD_ISSET(stderrChannel.pipe[0], &fdread))
+	if (qt_readable(fdset.stderr()))
 	    _q_canReadStandardError();
 
-	if (deathPipe[0] == -1 || FD_ISSET(deathPipe[0], &fdread)) {
+	if (qt_readable(fdset.death())) {
             if (_q_processDied())
                 return true;
 	}
@@ -1253,10 +1217,10 @@ bool QProcessPrivate::waitForFinished(int msecs)
 
 bool QProcessPrivate::waitForWrite(int msecs)
 {
-    fd_set fdwrite;
-    FD_ZERO(&fdwrite);
-    FD_SET(stdinChannel.pipe[1], &fdwrite);
-    return select_msecs(stdinChannel.pipe[1] + 1, 0, &fdwrite, msecs < 0 ? 0 : msecs) == 1;
+    pollfd fd;
+    fd.fd = stdinChannel.pipe[1];
+    fd.events = POLLIN;
+    return qt_safe_poll(&fd, 1, msecs);
 }
 
 void QProcessPrivate::findExitCode()
diff --git a/src/corelib/kernel/qcore_unix.cpp b/src/corelib/kernel/qcore_unix.cpp
index cc54798..ca178bb 100644
--- a/src/corelib/kernel/qcore_unix.cpp
+++ b/src/corelib/kernel/qcore_unix.cpp
@@ -103,4 +103,165 @@ int qt_safe_select(int nfds, fd_set *fdread, fd_set *fdwrite, fd_set *fdexcept,
     }
 }
 
+#ifndef Q_OS_VXWORKS
+
+int qt_safe_poll(struct pollfd *fds, int nfds, int timeout_ms, bool retry_eintr)
+{
+    if (nfds == 0)
+	return 0;
+    if (nfds < 0) {
+	errno = EINVAL;
+	return -1;
+    }
+
+    // Retry on ret == 0 if the deadline has not yet passed because
+    // Linux can return early from the syscall, without setting EINTR.
+    if (timeout_ms < 0) {
+	forever {
+	    int ret = ::poll(fds, nfds, -1);
+	    if (ret > 0)
+		return ret;
+	    if (retry_eintr) {
+		if (ret == 0 || ret == -1 && errno == EINTR) {
+		    continue;
+		} else {
+		    return -1;
+		}
+	    }
+	    if (ret == 0) {
+		errno = EINTR;
+		return -1;
+	    }
+	    return ret;
+	}
+    }
+
+    timeval previous = qt_gettime();
+    timeval deadline = previous;
+    deadline.tv_sec += timeout_ms / 1000;
+    deadline.tv_usec += (timeout_ms % 1000) * 1000;
+    if (deadline.tv_usec >= 1000000) {
+	++deadline.tv_sec;
+	deadline.tv_usec -= 1000000;
+    }
+    int remaining = timeout_ms;
+
+    forever {
+	int ret = ::poll(fds, nfds, remaining);
+	if (ret > 0)
+	    return ret;
+	timeval now = qt_gettime();
+	if ((now.tv_sec > deadline.tv_sec // past deadline
+	     || (now.tv_sec == deadline.tv_sec
+		 && now.tv_usec >= deadline.tv_usec))
+	    || (now.tv_sec < previous.tv_sec // time warp
+		|| (now.tv_sec == previous.tv_sec
+		    && now.tv_usec < previous.tv_usec))
+	    || (ret < 0 && (errno != EINTR || !retry_eintr))) // other error
+	    return ret;
+	if (ret == 0 && !retry_eintr) {
+	    errno = EINTR;
+	    return -1;
+	}
+        remaining = (deadline.tv_sec - now.tv_sec) * 1000
+		     + (deadline.tv_usec - now.tv_usec) / 1000;
+	previous = now;
+    }
+}
+
+#else
+
+// Poll emulation for VxWorks.
+
+static int mark_bad_descriptors(pollfd *fds, int nfds)
+{
+    fd_set r;
+    FD_ZERO(&r);
+    struct timeval tv;
+    tv.tv_sec = 0;
+    tv.tv_usec = 0;
+    int ret = 0;
+
+    // Check each descriptor invidually for badness.
+    for (int i = 0; i < nfds; ++i) {
+        pollfd &fd(fds[i]);
+        if (fd.fd >= 0) {
+            FD_SET(fd.fd, &r);
+            int ret = qt_safe_select(fd.fd + 1, &r, NULL, NULL, &tv);
+            FD_CLR(fd.fd, &r);
+            if (ret < 0 && errno == EBADF) {
+                fd.revents = POLLNVAL;
+                ++ret;
+            }
+        }
+    }
+    Q_ASSERT(ret > 0);
+    return ret;
+}
+
+int qt_safe_poll(pollfd *fds, int nfds, int timeout, bool retry_eintr)
+{
+    fd_set r, w;
+    FD_ZERO(&r);
+    FD_ZERO(&w);
+    int maxfd = -1;
+
+    // Extract the watched descriptors.
+    for (int i = 0; i < nfds; ++i) {
+        pollfd &fd(fds[i]);
+        if (fd.fd >= 0 && fd.fd < FD_SETSIZE) {
+            if (fd.events & POLLIN) {
+                FD_SET(fd.fd, &r);
+                if (fd.fd > maxfd)
+                    maxfd = fd.fd;
+            }
+            if (fd.events & POLLOUT) {
+                FD_SET(fd.fd, &w);
+                if (fd.fd > maxfd)
+                    maxfd = fd.fd;
+            }
+        }
+    }
+
+    // If timeout is negative, wait indefinitely for activity.
+    timeval tv;
+    timeval *ptv;
+    if (timeout >= 0) {
+        tv.tv_sec = timeout / 1000;
+        tv.tv_usec = (timeout % 1000) * 1000;
+        ptv = &tv;
+    } else
+        ptv = NULL;
+
+    int ret;
+    if (retry_eintr)
+        ret = qt_safe_select(maxfd + 1, &r, &w, NULL, ptv);
+    else
+        ret = ::select(maxfd + 1, &r, &w, NULL, ptv);
+    if (ret < 0 && errno == EBADF) {
+        return mark_bad_descriptors(fds, nfds);
+    }
+    if (ret <= 0)
+        return ret;
+
+    // Set the revents flags.
+    ret = 0;
+    for (int i = 0; i < nfds; ++i) {
+        pollfd &fd(fds[i]);
+        fd.revents = 0;
+        if (fd.fd >= 0 && fd.fd < FD_SETSIZE) {
+            if ((fd.events & POLLIN) && FD_ISSET(fd.fd, &r))
+                fd.revents |= POLLIN;
+            if ((fd.events & POLLOUT) && FD_ISSET(fd.fd, &w))
+                fd.revents |= POLLOUT;
+            if (fd.revents)
+                ++ret;
+        }
+    }
+    Q_ASSERT(ret > 0);
+    return ret;
+}
+
+#endif // Q_OS_VXWORKS
+
 QT_END_NAMESPACE
diff --git a/src/corelib/kernel/qcore_unix_p.h b/src/corelib/kernel/qcore_unix_p.h
index 6342b03..f7f4767 100644
--- a/src/corelib/kernel/qcore_unix_p.h
+++ b/src/corelib/kernel/qcore_unix_p.h
@@ -71,6 +71,8 @@
 
 #if defined(Q_OS_VXWORKS)
 #  include <ioLib.h>
+#else
+#  include <poll.h>
 #endif
 
 struct sockaddr;
@@ -341,6 +343,36 @@ void qt_nanosleep(timespec amount);
 Q_CORE_EXPORT int qt_safe_select(int nfds, fd_set *fdread, fd_set *fdwrite, fd_set *fdexcept,
                                  const struct timeval *tv);
 
+#ifdef Q_OS_VXWORKS
+// Poll emulation for VxWorks.  Provided by <poll.h> on other systems.
+
+struct pollfd {
+  int fd;
+  short events;
+  short revents;
+};
+
+#define POLLIN 1
+#define POLLOUT 2
+#define POLLERR 4
+#define POLLHUP 8
+#define POLLNVAL 16
+#endif
+
+inline bool qt_readable(const pollfd &fd)
+{
+  return fd.fd >= 0 && (fd.revents & (POLLIN | POLLHUP | POLLERR | POLLNVAL)) != 0;
+}
+
+inline bool qt_writable(const pollfd &fd)
+{
+  return fd.fd >= 0 && (fd.revents & (POLLOUT | POLLHUP | POLLERR | POLLNVAL)) != 0;
+}
+
+// Deprecated due to FD_SETSIZE limitation, use qt_safe_poll instead.
+Q_CORE_EXPORT int qt_safe_poll(pollfd *fds, int nfds, int timeout,
+                               bool retry_eintr = true);
+
 // according to X/OPEN we have to define semun ourselves
 // we use prefix as on some systems sem.h will have it
 struct semid_ds;
diff --git a/src/network/socket/qlocalserver_unix.cpp b/src/network/socket/qlocalserver_unix.cpp
index 2bcf1ac..efb8128 100644
--- a/src/network/socket/qlocalserver_unix.cpp
+++ b/src/network/socket/qlocalserver_unix.cpp
@@ -293,16 +293,11 @@ void QLocalServerPrivate::_q_onNewConnection()
 
 void QLocalServerPrivate::waitForNewConnection(int msec, bool *timedOut)
 {
-    fd_set readfds;
-    FD_ZERO(&readfds);
-    FD_SET(listenSocket, &readfds);
+    struct pollfd fd;
+    fd.fd = listenSocket;
+    fd.events = POLLIN;
 
-    timeval timeout;
-    timeout.tv_sec = msec / 1000;
-    timeout.tv_usec = (msec % 1000) * 1000;
-
-    int result = -1;
-    result = qt_safe_select(listenSocket + 1, &readfds, 0, 0, (msec == -1) ? 0 : &timeout);
+    int result = qt_safe_poll(&fd, 1, msec);
     if (-1 == result) {
         setError(QLatin1String("QLocalServer::waitForNewConnection"));
         closeServer();
diff --git a/src/network/socket/qlocalsocket_unix.cpp b/src/network/socket/qlocalsocket_unix.cpp
index 49eb71a..c598c2b 100644
--- a/src/network/socket/qlocalsocket_unix.cpp
+++ b/src/network/socket/qlocalsocket_unix.cpp
@@ -56,10 +56,6 @@
 #include <qdebug.h>
 #include <qelapsedtimer.h>
 
-#ifdef Q_OS_VXWORKS
-#  include <selectLib.h>
-#endif
-
 #define QT_CONNECT_TIMEOUT 30000
 
 QT_BEGIN_NAMESPACE
@@ -524,25 +520,16 @@ bool QLocalSocket::waitForConnected(int msec)
     if (state() != ConnectingState)
         return (state() == ConnectedState);
 
-    fd_set fds;
-    FD_ZERO(&fds);
-    FD_SET(d->connectingSocket, &fds);
-
-    timeval timeout;
-    timeout.tv_sec = msec / 1000;
-    timeout.tv_usec = (msec % 1000) * 1000;
+    pollfd fd;
+    fd.fd = d->connectingSocket;
+    fd.events = POLLIN | POLLOUT;
 
-    // timeout can not be 0 or else select will return an error.
-    if (0 == msec)
-        timeout.tv_usec = 1000;
-
-    int result = -1;
-    // on Linux timeout will be updated by select, but _not_ on other systems.
+    int result;
     QElapsedTimer timer;
+    int remaining = msec > 0 ? msec : 1000;
     timer.start();
-    while (state() == ConnectingState
-           && (-1 == msec || timer.elapsed() < msec)) {
-        result = ::select(d->connectingSocket + 1, &fds, 0, 0, &timeout);
+    while (state() == ConnectingState) {
+	result = qt_safe_poll(&fd, 1, remaining, /* retry_eintr */ false);
         if (-1 == result && errno != EINTR) {
             d->errorOccurred( QLocalSocket::UnknownSocketError,
                     QLatin1String("QLocalSocket::waitForConnected"));
@@ -550,6 +537,11 @@ bool QLocalSocket::waitForConnected(int msec)
         }
         if (result > 0)
             d->_q_connectToSocket();
+        if (msec >= 0) {
+            remaining = timer.elapsed() - msec;
+            if (remaining < 0)
+                break;
+        }
     }
 
     return (state() == ConnectedState);
diff --git a/src/network/socket/qnativesocketengine_unix.cpp b/src/network/socket/qnativesocketengine_unix.cpp
index 4f3408b..a1bb298 100644
--- a/src/network/socket/qnativesocketengine_unix.cpp
+++ b/src/network/socket/qnativesocketengine_unix.cpp
@@ -1122,48 +1122,40 @@ qint64 QNativeSocketEnginePrivate::nativeRead(char *data, qint64 maxSize)
 
 int QNativeSocketEnginePrivate::nativeSelect(int timeout, bool selectForRead) const
 {
-    fd_set fds;
-    FD_ZERO(&fds);
-    FD_SET(socketDescriptor, &fds);
-
-    struct timeval tv;
-    tv.tv_sec = timeout / 1000;
-    tv.tv_usec = (timeout % 1000) * 1000;
-
-    int retval;
-    if (selectForRead)
-        retval = qt_safe_select(socketDescriptor + 1, &fds, 0, 0, timeout < 0 ? 0 : &tv);
-    else
-        retval = qt_safe_select(socketDescriptor + 1, 0, &fds, 0, timeout < 0 ? 0 : &tv);
-
-    return retval;
+    struct pollfd fd;
+    fd.fd = socketDescriptor;
+    if (selectForRead) {
+	fd.events = POLLIN;
+    } else {
+	fd.events = POLLOUT;
+    }
+    return qt_safe_poll(&fd, 1, timeout);
 }
 
 int QNativeSocketEnginePrivate::nativeSelect(int timeout, bool checkRead, bool checkWrite,
                        bool *selectForRead, bool *selectForWrite) const
 {
-    fd_set fdread;
-    FD_ZERO(&fdread);
+    struct pollfd fd;
+    fd.fd = socketDescriptor;
     if (checkRead)
-        FD_SET(socketDescriptor, &fdread);
-
-    fd_set fdwrite;
-    FD_ZERO(&fdwrite);
+	fd.events =  POLLIN;
+    else
+	fd.events = 0;
     if (checkWrite)
-        FD_SET(socketDescriptor, &fdwrite);
-
-    struct timeval tv;
-    tv.tv_sec = timeout / 1000;
-    tv.tv_usec = (timeout % 1000) * 1000;
-
-    int ret;
-    ret = qt_safe_select(socketDescriptor + 1, &fdread, &fdwrite, 0, timeout < 0 ? 0 : &tv);
-
+	fd.events |= POLLOUT;
+    int ret = qt_safe_poll(&fd, 1, timeout);
     if (ret <= 0)
-        return ret;
-    *selectForRead = FD_ISSET(socketDescriptor, &fdread);
-    *selectForWrite = FD_ISSET(socketDescriptor, &fdwrite);
-
+	return ret;
+    bool r = (fd.revents & (POLLIN | POLLHUP | POLLERR)) != 0;
+    bool w = (fd.revents & (POLLOUT | POLLHUP | POLLERR)) != 0;
+    // Emulate the return value from select(2).
+    ret = 0;
+    if (r)
+	++ret;
+    if (w)
+	++ret;
+    *selectForRead = r;
+    *selectForWrite = w;
     return ret;
 }