diff options
Diffstat (limited to 'src/corelib/kernel/qsystemsemaphore_posix.cpp')
-rw-r--r-- | src/corelib/kernel/qsystemsemaphore_posix.cpp | 152 |
1 files changed, 0 insertions, 152 deletions
diff --git a/src/corelib/kernel/qsystemsemaphore_posix.cpp b/src/corelib/kernel/qsystemsemaphore_posix.cpp deleted file mode 100644 index 8f50d2a9a8..0000000000 --- a/src/corelib/kernel/qsystemsemaphore_posix.cpp +++ /dev/null @@ -1,152 +0,0 @@ -// Copyright (C) 2015 Konstantin Ritt <ritt.ks@gmail.com> -// Copyright (C) 2016 The Qt Company Ltd. -// Copyright (C) 2015 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Tobias Koenig <tobias.koenig@kdab.com> -// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only - -#include "qsystemsemaphore.h" -#include "qsystemsemaphore_p.h" - -#include <qdebug.h> -#include <qfile.h> -#include <qcoreapplication.h> - -#ifdef QT_POSIX_IPC - -#ifndef QT_NO_SYSTEMSEMAPHORE - -#include <sys/types.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 - -using namespace Qt::StringLiterals; - -bool QSystemSemaphorePrivate::handle(QSystemSemaphore::AccessMode mode) -{ - if (semaphore != SEM_FAILED) - return true; // we already have a semaphore - - if (fileName.isEmpty()) { - errorString = QSystemSemaphore::tr("%1: key is empty").arg("QSystemSemaphore::handle"_L1); - error = QSystemSemaphore::KeyError; - return false; - } - - const QByteArray semName = QFile::encodeName(fileName); - - // Always try with O_EXCL so we know whether we created the semaphore. - int oflag = O_CREAT | O_EXCL; - for (int tryNum = 0, maxTries = 1; tryNum < maxTries; ++tryNum) { - do { - semaphore = ::sem_open(semName.constData(), oflag, 0600, initialValue); - } while (semaphore == SEM_FAILED && errno == EINTR); - if (semaphore == SEM_FAILED && errno == EEXIST) { - if (mode == QSystemSemaphore::Create) { - if (::sem_unlink(semName.constData()) == -1 && errno != ENOENT) { - setErrorString("QSystemSemaphore::handle (sem_unlink)"_L1); - return false; - } - // Race condition: the semaphore might be recreated before - // we call sem_open again, so we'll retry several times. - maxTries = 3; - } else { - // Race condition: if it no longer exists at the next sem_open - // call, we won't realize we created it, so we'll leak it later. - oflag &= ~O_EXCL; - maxTries = 2; - } - } else { - break; - } - } - - if (semaphore == SEM_FAILED) { - setErrorString("QSystemSemaphore::handle"_L1); - return false; - } - - createdSemaphore = (oflag & O_EXCL) != 0; - - return true; -} - -void QSystemSemaphorePrivate::cleanHandle() -{ - if (semaphore != SEM_FAILED) { - if (::sem_close(semaphore) == -1) { - setErrorString("QSystemSemaphore::cleanHandle (sem_close)"_L1); -#if defined QSYSTEMSEMAPHORE_DEBUG - qDebug("QSystemSemaphore::cleanHandle sem_close failed."); -#endif - } - semaphore = SEM_FAILED; - } - - if (createdSemaphore) { - if (::sem_unlink(QFile::encodeName(fileName).constData()) == -1 && errno != ENOENT) { - setErrorString("QSystemSemaphore::cleanHandle (sem_unlink)"_L1); -#if defined QSYSTEMSEMAPHORE_DEBUG - qDebug("QSystemSemaphore::cleanHandle sem_unlink failed."); -#endif - } - createdSemaphore = false; - } -} - -bool QSystemSemaphorePrivate::modifySemaphore(int count) -{ - if (!handle()) - return false; - - if (count > 0) { - int cnt = count; - do { - if (::sem_post(semaphore) == -1) { - setErrorString("QSystemSemaphore::modifySemaphore (sem_post)"_L1); -#if defined QSYSTEMSEMAPHORE_DEBUG - qDebug("QSystemSemaphore::modify sem_post failed %d %d", count, errno); -#endif - // rollback changes to preserve the SysV semaphore behavior - for ( ; cnt < count; ++cnt) { - int res; - EINTR_LOOP(res, ::sem_wait(semaphore)); - } - return false; - } - --cnt; - } while (cnt > 0); - } else { - int res; - EINTR_LOOP(res, ::sem_wait(semaphore)); - if (res == -1) { - // If the semaphore was removed be nice and create it and then modifySemaphore again - if (errno == EINVAL || errno == EIDRM) { - semaphore = SEM_FAILED; - return modifySemaphore(count); - } - setErrorString("QSystemSemaphore::modifySemaphore (sem_wait)"_L1); -#if defined QSYSTEMSEMAPHORE_DEBUG - qDebug("QSystemSemaphore::modify sem_wait failed %d %d", count, errno); -#endif - return false; - } - } - - clearError(); - return true; -} - -QT_END_NAMESPACE - -#endif // QT_NO_SYSTEMSEMAPHORE - -#endif // QT_POSIX_IPC |