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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 238 insertions, 0 deletions

diff --git a/src/corelib/kernel/qsystemsemaphore_unix.cpp b/src/corelib/kernel/qsystemsemaphore_unix.cpp
new file mode 100644
index 0000000000..55b65b75de
--- /dev/null
+++ b/src/corelib/kernel/qsystemsemaphore_unix.cpp
@@ -0,0 +1,238 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qsystemsemaphore.h"
+#include "qsystemsemaphore_p.h"
+
+#include <qdebug.h>
+#include <qfile.h>
+#include <qcoreapplication.h>
+
+#ifndef QT_NO_SYSTEMSEMAPHORE
+
+#include <sys/types.h>
+#include <sys/ipc.h>
+#include <sys/sem.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include "private/qcore_unix_p.h"
+
+// OpenBSD 4.2 doesn't define EIDRM, see BUGS section:
+// http://www.openbsd.org/cgi-bin/man.cgi?query=semop&manpath=OpenBSD+4.2
+#if defined(Q_OS_OPENBSD) && !defined(EIDRM)
+#define EIDRM EINVAL
+#endif
+
+QT_BEGIN_NAMESPACE
+
+QSystemSemaphorePrivate::QSystemSemaphorePrivate() :
+        semaphore(-1), createdFile(false),
+        createdSemaphore(false), unix_key(-1), error(QSystemSemaphore::NoError)
+{
+}
+
+void QSystemSemaphorePrivate::setErrorString(const QString &function)
+{
+    // EINVAL is handled in functions so they can give better error strings
+    switch (errno) {
+    case EPERM:
+    case EACCES:
+        errorString = QCoreApplication::translate("QSystemSemaphore", "%1: permission denied").arg(function);
+        error = QSystemSemaphore::PermissionDenied;
+        break;
+    case EEXIST:
+        errorString = QCoreApplication::translate("QSystemSemaphore", "%1: already exists").arg(function);
+        error = QSystemSemaphore::AlreadyExists;
+        break;
+    case ENOENT:
+        errorString = QCoreApplication::translate("QSystemSemaphore", "%1: does not exist").arg(function);
+        error = QSystemSemaphore::NotFound;
+        break;
+    case ERANGE:
+    case ENOSPC:
+        errorString = QCoreApplication::translate("QSystemSemaphore", "%1: out of resources").arg(function);
+        error = QSystemSemaphore::OutOfResources;
+        break;
+    default:
+        errorString = QCoreApplication::translate("QSystemSemaphore", "%1: unknown error %2").arg(function).arg(errno);
+        error = QSystemSemaphore::UnknownError;
+#if defined QSYSTEMSEMAPHORE_DEBUG
+        qDebug() << errorString << "key" << key << "errno" << errno << EINVAL;
+#endif
+    }
+}
+
+/*!
+    \internal
+
+    Setup unix_key
+ */
+key_t QSystemSemaphorePrivate::handle(QSystemSemaphore::AccessMode mode)
+{
+    if (key.isEmpty()){
+        errorString = QCoreApplication::tr("%1: key is empty", "QSystemSemaphore").arg(QLatin1String("QSystemSemaphore::handle:"));
+        error = QSystemSemaphore::KeyError;
+        return -1;
+    }
+
+    // ftok requires that an actual file exists somewhere
+    if (-1 != unix_key)
+        return unix_key;
+
+    // Create the file needed for ftok
+    int built = QSharedMemoryPrivate::createUnixKeyFile(fileName);
+    if (-1 == built) {
+        errorString = QCoreApplication::tr("%1: unable to make key", "QSystemSemaphore").arg(QLatin1String("QSystemSemaphore::handle:"));
+        error = QSystemSemaphore::KeyError;
+        return -1;
+    }
+    createdFile = (1 == built);
+
+    // Get the unix key for the created file
+    unix_key = ftok(QFile::encodeName(fileName).constData(), 'Q');
+    if (-1 == unix_key) {
+        errorString = QCoreApplication::tr("%1: ftok failed", "QSystemSemaphore").arg(QLatin1String("QSystemSemaphore::handle:"));
+        error = QSystemSemaphore::KeyError;
+        return -1;
+    }
+
+    // Get semaphore
+    semaphore = semget(unix_key, 1, 0666 | IPC_CREAT | IPC_EXCL);
+    if (-1 == semaphore) {
+        if (errno == EEXIST)
+            semaphore = semget(unix_key, 1, 0666 | IPC_CREAT);
+        if (-1 == semaphore) {
+            setErrorString(QLatin1String("QSystemSemaphore::handle"));
+            cleanHandle();
+            return -1;
+        }
+    } else {
+        createdSemaphore = true;
+        // Force cleanup of file, it is possible that it can be left over from a crash
+        createdFile = true;
+    }
+
+    if (mode == QSystemSemaphore::Create) {
+        createdSemaphore = true;
+        createdFile = true;
+    }
+
+    // Created semaphore so initialize its value.
+    if (createdSemaphore && initialValue >= 0) {
+        qt_semun init_op;
+        init_op.val = initialValue;
+        if (-1 == semctl(semaphore, 0, SETVAL, init_op)) {
+            setErrorString(QLatin1String("QSystemSemaphore::handle"));
+            cleanHandle();
+            return -1;
+        }
+    }
+
+    return unix_key;
+}
+
+/*!
+    \internal
+
+    Cleanup the unix_key
+ */
+void QSystemSemaphorePrivate::cleanHandle()
+{
+    unix_key = -1;
+
+    // remove the file if we made it
+    if (createdFile) {
+        QFile::remove(fileName);
+        createdFile = false;
+    }
+
+    if (createdSemaphore) {
+        if (-1 != semaphore) {
+            if (-1 == semctl(semaphore, 0, IPC_RMID, 0)) {
+                setErrorString(QLatin1String("QSystemSemaphore::cleanHandle"));
+#if defined QSYSTEMSEMAPHORE_DEBUG
+                qDebug() << QLatin1String("QSystemSemaphore::cleanHandle semctl failed.");
+#endif
+            }
+            semaphore = -1;
+        }
+        createdSemaphore = false;
+    }
+}
+
+/*!
+    \internal
+ */
+bool QSystemSemaphorePrivate::modifySemaphore(int count)
+{
+    if (-1 == handle())
+        return false;
+
+    struct sembuf operation;
+    operation.sem_num = 0;
+    operation.sem_op = count;
+    operation.sem_flg = SEM_UNDO;
+
+    register int res;
+    EINTR_LOOP(res, semop(semaphore, &operation, 1));
+    if (-1 == res) {
+        // If the semaphore was removed be nice and create it and then modifySemaphore again
+        if (errno == EINVAL || errno == EIDRM) {
+            semaphore = -1;
+            cleanHandle();
+            handle();
+            return modifySemaphore(count);
+        }
+        setErrorString(QLatin1String("QSystemSemaphore::modifySemaphore"));
+#if defined QSYSTEMSEMAPHORE_DEBUG
+        qDebug() << QLatin1String("QSystemSemaphore::modify failed") << count << semctl(semaphore, 0, GETVAL) << errno << EIDRM << EINVAL;
+#endif
+        return false;
+    }
+
+    return true;
+}
+
+
+QT_END_NAMESPACE
+
+#endif // QT_NO_SYSTEMSEMAPHORE