make QProcess really work on QNX

a multi-threaded QNX Process can't fork properly so we call spawn() instead

Merge-request: 1259
Reviewed-by: Harald Fernengel <harald.fernengel@nokia.com>

4 files changed, 179 insertions, 24 deletions

diff --git a/src/corelib/global/qglobal.h b/src/corelib/global/qglobal.h
index 32b3e6b..08f9eb0 100644
--- a/src/corelib/global/qglobal.h
+++ b/src/corelib/global/qglobal.h
@@ -2753,8 +2753,6 @@ QT_LICENSED_MODULE(DBus)
 #  define QT_NO_QWS_SHARE_FONTS
 #  define QT_NO_SYSTEMSEMAPHORE
 #  define QT_NO_SHAREDMEMORY
-// QNX currently doesn't support forking in a thread, so disable QProcess
-#  define QT_NO_PROCESS
 #endif
 
 #if defined (__ELF__)
diff --git a/src/corelib/io/qprocess.cpp b/src/corelib/io/qprocess.cpp
index 70a70c2..4b689c5 100644
--- a/src/corelib/io/qprocess.cpp
+++ b/src/corelib/io/qprocess.cpp
@@ -751,12 +751,16 @@ QProcessPrivate::QProcessPrivate()
     sequenceNumber = 0;
     exitCode = 0;
     exitStatus = QProcess::NormalExit;
+#ifndef Q_OS_QNX
     startupSocketNotifier = 0;
+#endif
     deathNotifier = 0;
     notifier = 0;
     pipeWriter = 0;
+#ifndef Q_OS_QNX
     childStartedPipe[0] = INVALID_Q_PIPE;
     childStartedPipe[1] = INVALID_Q_PIPE;
+#endif
     deathPipe[0] = INVALID_Q_PIPE;
     deathPipe[1] = INVALID_Q_PIPE;
     exitCode = 0;
@@ -825,11 +829,13 @@ void QProcessPrivate::cleanup()
         qDeleteInEventHandler(stdinChannel.notifier);
         stdinChannel.notifier = 0;
     }
+#ifndef Q_OS_QNX
     if (startupSocketNotifier) {
         startupSocketNotifier->setEnabled(false);
         qDeleteInEventHandler(startupSocketNotifier);
         startupSocketNotifier = 0;
     }
+#endif
     if (deathNotifier) {
         deathNotifier->setEnabled(false);
         qDeleteInEventHandler(deathNotifier);
@@ -842,7 +848,9 @@ void QProcessPrivate::cleanup()
     destroyPipe(stdoutChannel.pipe);
     destroyPipe(stderrChannel.pipe);
     destroyPipe(stdinChannel.pipe);
+#ifndef Q_OS_QNX
     destroyPipe(childStartedPipe);
+#endif
     destroyPipe(deathPipe);
 #ifdef Q_OS_UNIX
     serial = 0;
@@ -1077,8 +1085,10 @@ bool QProcessPrivate::_q_startupNotification()
     qDebug("QProcessPrivate::startupNotification()");
 #endif
 
+#ifndef Q_OS_QNX
     if (startupSocketNotifier)
         startupSocketNotifier->setEnabled(false);
+#endif
     if (processStarted()) {
         q->setProcessState(QProcess::Running);
         emit q->started();
diff --git a/src/corelib/io/qprocess_p.h b/src/corelib/io/qprocess_p.h
index 9adb331..f24a7bc 100644
--- a/src/corelib/io/qprocess_p.h
+++ b/src/corelib/io/qprocess_p.h
@@ -288,11 +288,15 @@ public:
     QRingBuffer errorReadBuffer;
     QRingBuffer writeBuffer;
 
+#ifndef Q_OS_QNX
     Q_PIPE childStartedPipe[2];
+#endif
     Q_PIPE deathPipe[2];
     void destroyPipe(Q_PIPE pipe[2]);
 
+#ifndef Q_OS_QNX
     QSocketNotifier *startupSocketNotifier;
+#endif
     QSocketNotifier *deathNotifier;
 
     // the wonderful windows notifier
@@ -301,8 +305,10 @@ public:
     QWinEventNotifier *processFinishedNotifier;
 
     void startProcess();
-#if defined(Q_OS_UNIX) && !defined(Q_OS_SYMBIAN)
+#if defined(Q_OS_UNIX) && !defined(Q_OS_SYMBIAN) && !defined(Q_OS_QNX)
     void execChild(const char *workingDirectory, char **path, char **argv, char **envp);
+#elif defined(Q_OS_QNX)
+    pid_t spawnChild(const char *workingDirectory, char **argv, char **envp);
 #endif
     bool processStarted();
     void terminateProcess();
diff --git a/src/corelib/io/qprocess_unix.cpp b/src/corelib/io/qprocess_unix.cpp
index 07e3087..725e4c5 100644
--- a/src/corelib/io/qprocess_unix.cpp
+++ b/src/corelib/io/qprocess_unix.cpp
@@ -105,6 +105,10 @@ QT_END_NAMESPACE
 #include <errno.h>
 #include <stdlib.h>
 #include <string.h>
+#ifdef Q_OS_QNX
+#  include <spawn.h>
+#endif
+
 
 QT_BEGIN_NAMESPACE
 
@@ -521,16 +525,6 @@ static char **_q_dupEnvironment(const QProcessEnvironmentPrivate::Hash &environm
     return envp;
 }
 
-// under QNX RTOS we have to use vfork() when multithreading
-inline pid_t qt_fork()
-{
-#if defined(Q_OS_QNX)
-    return vfork();
-#else
-    return fork();
-#endif
-}
-
 #ifdef Q_OS_MAC
 Q_GLOBAL_STATIC(QMutex, cfbundleMutex);
 #endif
@@ -550,15 +544,18 @@ void QProcessPrivate::startProcess()
         !createChannel(stdoutChannel) ||
         !createChannel(stderrChannel))
         return;
+#if !defined(Q_OS_QNX)
     qt_create_pipe(childStartedPipe);
+#endif
     qt_create_pipe(deathPipe);
 
     if (threadData->eventDispatcher) {
+#if !defined(Q_OS_QNX)
         startupSocketNotifier = new QSocketNotifier(childStartedPipe[0],
                                                     QSocketNotifier::Read, q);
         QObject::connect(startupSocketNotifier, SIGNAL(activated(int)),
                          q, SLOT(_q_startupNotification()));
-
+#endif
         deathNotifier = new QSocketNotifier(deathPipe[0],
                                             QSocketNotifier::Read, q);
         QObject::connect(deathNotifier, SIGNAL(activated(int)),
@@ -650,7 +647,11 @@ void QProcessPrivate::startProcess()
 
     // Start the process manager, and fork off the child process.
     processManager()->lock();
-    pid_t childPid = qt_fork();
+#if defined(Q_OS_QNX)
+    pid_t childPid = spawnChild(workingDirPtr, argv, envp);
+#else
+    pid_t childPid = fork();
+#endif
     int lastForkErrno = errno;
     if (childPid != 0) {
         // Clean up duplicated memory.
@@ -668,7 +669,7 @@ void QProcessPrivate::startProcess()
     if (childPid < 0) {
         // Cleanup, report error and return
 #if defined (QPROCESS_DEBUG)
-        qDebug("qt_fork failed: %s", qPrintable(qt_error_string(lastForkErrno)));
+        qDebug("fork() failed: %s", qPrintable(qt_error_string(lastForkErrno)));
 #endif
         processManager()->unlock();
         q->setProcessState(QProcess::NotRunning);
@@ -679,11 +680,13 @@ void QProcessPrivate::startProcess()
         return;
     }
 
+#if !defined(Q_OS_QNX)
     // Start the child.
     if (childPid == 0) {
         execChild(workingDirPtr, path, argv, envp);
         ::_exit(-1);
     }
+#endif
 
     // Register the child. In the mean time, we can get a SIGCHLD, so we need
     // to keep the lock held to avoid a race to catch the child.
@@ -694,14 +697,15 @@ void QProcessPrivate::startProcess()
     // parent
     // close the ends we don't use and make all pipes non-blocking
     ::fcntl(deathPipe[0], F_SETFL, ::fcntl(deathPipe[0], F_GETFL) | O_NONBLOCK);
+#if !defined(Q_OS_QNX)
     qt_safe_close(childStartedPipe[1]);
     childStartedPipe[1] = -1;
+#endif
 
     if (stdinChannel.pipe[0] != -1) {
         qt_safe_close(stdinChannel.pipe[0]);
         stdinChannel.pipe[0] = -1;
     }
-
     if (stdinChannel.pipe[1] != -1)
         ::fcntl(stdinChannel.pipe[1], F_SETFL, ::fcntl(stdinChannel.pipe[1], F_GETFL) | O_NONBLOCK);
 
@@ -709,7 +713,6 @@ void QProcessPrivate::startProcess()
         qt_safe_close(stdoutChannel.pipe[1]);
         stdoutChannel.pipe[1] = -1;
     }
-
     if (stdoutChannel.pipe[0] != -1)
         ::fcntl(stdoutChannel.pipe[0], F_SETFL, ::fcntl(stdoutChannel.pipe[0], F_GETFL) | O_NONBLOCK);
 
@@ -721,6 +724,7 @@ void QProcessPrivate::startProcess()
         ::fcntl(stderrChannel.pipe[0], F_SETFL, ::fcntl(stderrChannel.pipe[0], F_GETFL) | O_NONBLOCK);
 }
 
+#if !defined(Q_OS_QNX)
 void QProcessPrivate::execChild(const char *workingDir, char **path, char **argv, char **envp)
 {
     ::signal(SIGPIPE, SIG_DFL);         // reset the signal that we ignored
@@ -728,17 +732,17 @@ void QProcessPrivate::execChild(const char *workingDir, char **path, char **argv
     Q_Q(QProcess);
 
     // copy the stdin socket (without closing on exec)
-    qt_safe_dup2(stdinChannel.pipe[0], fileno(stdin), 0);
+    qt_safe_dup2(stdinChannel.pipe[0], QT_FILENO(stdin), 0);
 
     // copy the stdout and stderr if asked to
     if (processChannelMode != QProcess::ForwardedChannels) {
-        qt_safe_dup2(stdoutChannel.pipe[1], fileno(stdout), 0);
+        qt_safe_dup2(stdoutChannel.pipe[1], QT_FILENO(stdout), 0);
 
         // merge stdout and stderr if asked to
         if (processChannelMode == QProcess::MergedChannels) {
-            qt_safe_dup2(fileno(stdout), fileno(stderr), 0);
+            qt_safe_dup2(QT_FILENO(stdout), QT_FILENO(stderr), 0);
         } else {
-            qt_safe_dup2(stderrChannel.pipe[1], fileno(stderr), 0);
+            qt_safe_dup2(stderrChannel.pipe[1], QT_FILENO(stderr), 0);
         }
     }
 
@@ -807,6 +811,87 @@ bool QProcessPrivate::processStarted()
     return i <= 0;
 }
 
+#else // Q_OS_QNX
+
+static pid_t doSpawn(int fd_count, int fd_map[], char **argv, char **envp, bool spawn_detached)
+{
+    // A multi threaded QNX Process can't fork so we call spawn() instead.
+
+    struct inheritance inherit;
+    memset(&inherit, 0, sizeof(inherit));
+    inherit.flags |= SPAWN_SETSID;
+    inherit.flags |= SPAWN_CHECK_SCRIPT;
+    if (spawn_detached)
+        inherit.flags |= SPAWN_NOZOMBIE;
+    inherit.flags |= SPAWN_SETSIGDEF;
+    sigaddset(&inherit.sigdefault, SIGPIPE); // reset the signal that we ignored
+
+    pid_t childPid;
+    EINTR_LOOP(childPid, ::spawn(argv[0], fd_count, fd_map, &inherit, argv, envp));
+    if (childPid == -1) {
+        inherit.flags |= SPAWN_SEARCH_PATH;
+        EINTR_LOOP(childPid, ::spawn(argv[0], fd_count, fd_map, &inherit, argv, envp));
+    }
+
+    return childPid;
+}
+
+pid_t QProcessPrivate::spawnChild(const char *workingDir, char **argv, char **envp)
+{
+    Q_Q(QProcess);
+
+    const int fd_count = 3;
+    int fd_map[fd_count];
+    switch (processChannelMode) {
+    case QProcess::ForwardedChannels:
+        fd_map[0] = stdinChannel.pipe[0];
+        fd_map[1] = QT_FILENO(stdout);
+        fd_map[2] = QT_FILENO(stderr);
+        break;
+    case QProcess::MergedChannels:
+        fd_map[0] = stdinChannel.pipe[0];
+        fd_map[1] = stdoutChannel.pipe[1];
+        fd_map[2] = stdoutChannel.pipe[1];
+        break;
+    case QProcess::SeparateChannels:
+        fd_map[0] = stdinChannel.pipe[0];
+        fd_map[1] = stdoutChannel.pipe[1];
+        fd_map[2] = stderrChannel.pipe[1];
+        break;
+    }
+
+    // enter the working directory
+    char *oldWorkingDir = 0;
+    char buff[PATH_MAX + 1];
+    if (workingDir) {
+        oldWorkingDir = QT_GETCWD(buff, PATH_MAX + 1);
+        QT_CHDIR(workingDir);
+    }
+
+    pid_t childPid = doSpawn(fd_count, fd_map, argv, envp, false);
+
+    if (oldWorkingDir)
+        QT_CHDIR(oldWorkingDir);
+
+    if (childPid != -1) {
+        q->setProcessState(QProcess::Running);
+        QMetaObject::invokeMethod(q, "_q_startupNotification", Qt::QueuedConnection);
+    }
+
+    return childPid;
+}
+
+bool QProcessPrivate::processStarted()
+{
+    return processState == QProcess::Running;
+}
+
+bool QProcessPrivate::waitForStarted(int /*msecs*/)
+{
+    return processStarted();
+}
+#endif // Q_OS_QNX
+
 qint64 QProcessPrivate::bytesAvailableFromStdout() const
 {
     int nbytes = 0;
@@ -924,6 +1009,7 @@ static int qt_timeout_value(int msecs, int elapsed)
     return timeout < 0 ? 0 : timeout;
 }
 
+#if !defined(Q_OS_QNX)
 bool QProcessPrivate::waitForStarted(int msecs)
 {
     Q_Q(QProcess);
@@ -951,6 +1037,7 @@ bool QProcessPrivate::waitForStarted(int msecs)
 #endif
     return startedEmitted;
 }
+#endif // Q_OS_QNX
 
 bool QProcessPrivate::waitForReadyRead(int msecs)
 {
@@ -972,8 +1059,10 @@ bool QProcessPrivate::waitForReadyRead(int msecs)
         int nfds = deathPipe[0];
         FD_SET(deathPipe[0], &fdread);
 
+#if !defined(Q_OS_QNX)
         if (processState == QProcess::Starting)
             add_fd(nfds, childStartedPipe[0], &fdread);
+#endif
 
         if (stdoutChannel.pipe[0] != -1)
             add_fd(nfds, stdoutChannel.pipe[0], &fdread);
@@ -994,10 +1083,12 @@ bool QProcessPrivate::waitForReadyRead(int msecs)
 	    return false;
 	}
 
+#if !defined(Q_OS_QNX)
 	if (childStartedPipe[0] != -1 && FD_ISSET(childStartedPipe[0], &fdread)) {
             if (!_q_startupNotification())
                 return false;
 	}
+#endif
 
         bool readyReadEmitted = false;
 	if (stdoutChannel.pipe[0] != -1 && FD_ISSET(stdoutChannel.pipe[0], &fdread)) {
@@ -1044,8 +1135,10 @@ bool QProcessPrivate::waitForBytesWritten(int msecs)
         int nfds = deathPipe[0];
         FD_SET(deathPipe[0], &fdread);
 
+#if !defined(Q_OS_QNX)
         if (processState == QProcess::Starting)
             add_fd(nfds, childStartedPipe[0], &fdread);
+#endif
 
         if (stdoutChannel.pipe[0] != -1)
             add_fd(nfds, stdoutChannel.pipe[0], &fdread);
@@ -1068,10 +1161,12 @@ bool QProcessPrivate::waitForBytesWritten(int msecs)
 	    return false;
 	}
 
+#if !defined(Q_OS_QNX)
 	if (childStartedPipe[0] != -1 && FD_ISSET(childStartedPipe[0], &fdread)) {
 	    if (!_q_startupNotification())
 		return false;
 	}
+#endif
 
 	if (stdinChannel.pipe[1] != -1 && FD_ISSET(stdinChannel.pipe[1], &fdwrite))
 	    return _q_canWrite();
@@ -1109,8 +1204,10 @@ bool QProcessPrivate::waitForFinished(int msecs)
         FD_ZERO(&fdread);
         FD_ZERO(&fdwrite);
 
+#if !defined(Q_OS_QNX)
         if (processState == QProcess::Starting)
             add_fd(nfds, childStartedPipe[0], &fdread);
+#endif
 
         if (stdoutChannel.pipe[0] != -1)
             add_fd(nfds, stdoutChannel.pipe[0], &fdread);
@@ -1134,10 +1231,12 @@ bool QProcessPrivate::waitForFinished(int msecs)
 	    return false;
 	}
 
+#if !defined(Q_OS_QNX)
 	if (childStartedPipe[0] != -1 && FD_ISSET(childStartedPipe[0], &fdread)) {
 	    if (!_q_startupNotification())
 		return false;
 	}
+#endif
 	if (stdinChannel.pipe[1] != -1 && FD_ISSET(stdinChannel.pipe[1], &fdwrite))
 	    _q_canWrite();
 
@@ -1199,6 +1298,47 @@ void QProcessPrivate::_q_notified()
 {
 }
 
+#if defined(Q_OS_QNX)
+bool QProcessPrivate::startDetached(const QString &program, const QStringList &arguments, const QString &workingDirectory, qint64 *pid)
+{
+    QByteArray encodedWorkingDirectory = QFile::encodeName(workingDirectory);
+
+    // enter the working directory
+    char *oldWorkingDir = 0;
+    char buff[PATH_MAX + 1];
+    if (!encodedWorkingDirectory.isEmpty()) {
+        oldWorkingDir = QT_GETCWD(buff, PATH_MAX + 1);
+        QT_CHDIR(encodedWorkingDirectory.constData());
+    }
+
+    const int fd_count = 3;
+    int fd_map[fd_count] = { QT_FILENO(stdin), QT_FILENO(stdout), QT_FILENO(stderr) };
+
+    QList<QByteArray> enc_args;
+    enc_args.append(QFile::encodeName(program));
+    for (int i = 0; i < arguments.size(); ++i)
+        enc_args.append(arguments.at(i).toLocal8Bit());
+
+    const int argc = enc_args.size();
+    QScopedArrayPointer<char*> raw_argv(new char*[argc + 1]);
+    for (int i = 0; i < argc; ++i)
+        raw_argv[i] = const_cast<char *>(enc_args.at(i).data());
+    raw_argv[argc] = 0;
+
+    char **envp = 0; // inherit environment
+
+    pid_t childPid = doSpawn(fd_count, fd_map, raw_argv.data(), envp, true);
+    if (pid && childPid != -1)
+        *pid = childPid;
+
+    if (oldWorkingDir)
+        QT_CHDIR(oldWorkingDir);
+
+    return childPid != -1;
+}
+
+#else
+
 bool QProcessPrivate::startDetached(const QString &program, const QStringList &arguments, const QString &workingDirectory, qint64 *pid)
 {
     processManager()->start();
@@ -1212,7 +1352,7 @@ bool QProcessPrivate::startDetached(const QString &program, const QStringList &a
     int pidPipe[2];
     qt_safe_pipe(pidPipe);
 
-    pid_t childPid = qt_fork();
+    pid_t childPid = fork();
     if (childPid == 0) {
         struct sigaction noaction;
         memset(&noaction, 0, sizeof(noaction));
@@ -1224,7 +1364,7 @@ bool QProcessPrivate::startDetached(const QString &program, const QStringList &a
         qt_safe_close(startedPipe[0]);
         qt_safe_close(pidPipe[0]);
 
-        pid_t doubleForkPid = qt_fork();
+        pid_t doubleForkPid = fork();
         if (doubleForkPid == 0) {
             qt_safe_close(pidPipe[1]);
 
@@ -1312,6 +1452,7 @@ bool QProcessPrivate::startDetached(const QString &program, const QStringList &a
     qt_safe_close(pidPipe[0]);
     return success;
 }
+#endif // Q_OS_QNX
 
 void QProcessPrivate::initializeProcessManager()
 {