diff options
author | Tobias Koenig <tobias.koenig@kdab.com> | 2014-12-22 11:24:41 +0100 |
---|---|---|
committer | Tobias Koenig <tobias.koenig@kdab.com> | 2015-01-09 10:58:52 +0100 |
commit | 96995db4af6e1f5e9fe313e4c71a41fd939fedf8 (patch) | |
tree | 8445e4bec938e15d48fc0d8c77113211abc05aa1 /src/corelib/kernel/qsharedmemory_unix.cpp | |
parent | c3e50db19990c5b1d9088c4418e2804560d35582 (diff) |
Add POSIX IPC support to QSystemSemaphore and QSharedMemory
This patch is a forward-port from 4.8 branch
(d869e1ad4b0007757e97046609de2097cd9e9c5d).
Change-Id: I6ae36a5417d1176fbecf775668f6033b1cb22a94
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Diffstat (limited to 'src/corelib/kernel/qsharedmemory_unix.cpp')
-rw-r--r-- | src/corelib/kernel/qsharedmemory_unix.cpp | 199 |
1 files changed, 8 insertions, 191 deletions
diff --git a/src/corelib/kernel/qsharedmemory_unix.cpp b/src/corelib/kernel/qsharedmemory_unix.cpp index 8d616af4fe..5ba770c212 100644 --- a/src/corelib/kernel/qsharedmemory_unix.cpp +++ b/src/corelib/kernel/qsharedmemory_unix.cpp @@ -36,7 +36,6 @@ #include "qsharedmemory.h" #include "qsharedmemory_p.h" #include "qsystemsemaphore.h" -#include <qdir.h> #include <qdebug.h> #include <errno.h> @@ -44,7 +43,11 @@ #ifndef QT_NO_SHAREDMEMORY #include <sys/types.h> #include <sys/ipc.h> +#ifndef QT_POSIX_IPC #include <sys/shm.h> +#else +#include <sys/mman.h> +#endif #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> @@ -60,7 +63,11 @@ QSharedMemoryPrivate::QSharedMemoryPrivate() #ifndef QT_NO_SYSTEMSEMAPHORE systemSemaphore(QString()), lockedByMe(false), #endif +#ifndef QT_POSIX_IPC unix_key(0) +#else + hand(-1) +#endif { } @@ -95,196 +102,6 @@ void QSharedMemoryPrivate::setErrorString(const QString &function) } } -/*! - \internal - - If not already made create the handle used for accessing the shared memory. -*/ -key_t QSharedMemoryPrivate::handle() -{ - // already made - if (unix_key) - return unix_key; - - // don't allow making handles on empty keys - if (nativeKey.isEmpty()) { - errorString = QSharedMemory::tr("%1: key is empty").arg(QLatin1String("QSharedMemory::handle:")); - error = QSharedMemory::KeyError; - return 0; - } - - // ftok requires that an actual file exists somewhere - if (!QFile::exists(nativeKey)) { - errorString = QSharedMemory::tr("%1: UNIX key file doesn't exist").arg(QLatin1String("QSharedMemory::handle:")); - error = QSharedMemory::NotFound; - return 0; - } - - unix_key = ftok(QFile::encodeName(nativeKey).constData(), 'Q'); - if (-1 == unix_key) { - errorString = QSharedMemory::tr("%1: ftok failed").arg(QLatin1String("QSharedMemory::handle:")); - error = QSharedMemory::KeyError; - unix_key = 0; - } - return unix_key; -} - -#endif // QT_NO_SHAREDMEMORY - -#if !(defined(QT_NO_SHAREDMEMORY) && defined(QT_NO_SYSTEMSEMAPHORE)) -/*! - \internal - Creates the unix file if needed. - returns \c true if the unix file was created. - - -1 error - 0 already existed - 1 created - */ -int QSharedMemoryPrivate::createUnixKeyFile(const QString &fileName) -{ - int fd = qt_safe_open(QFile::encodeName(fileName).constData(), - O_EXCL | O_CREAT | O_RDWR, 0640); - if (-1 == fd) { - if (errno == EEXIST) - return 0; - return -1; - } else { - close(fd); - } - return 1; -} -#endif // QT_NO_SHAREDMEMORY && QT_NO_SYSTEMSEMAPHORE - -#ifndef QT_NO_SHAREDMEMORY - -bool QSharedMemoryPrivate::cleanHandle() -{ - unix_key = 0; - return true; -} - -bool QSharedMemoryPrivate::create(int size) -{ - // build file if needed - bool createdFile = false; - int built = createUnixKeyFile(nativeKey); - if (built == -1) { - errorString = QSharedMemory::tr("%1: unable to make key").arg(QLatin1String("QSharedMemory::handle:")); - error = QSharedMemory::KeyError; - return false; - } - if (built == 1) { - createdFile = true; - } - - // get handle - if (!handle()) { - if (createdFile) - QFile::remove(nativeKey); - return false; - } - - // create - if (-1 == shmget(unix_key, size, 0600 | IPC_CREAT | IPC_EXCL)) { - QString function = QLatin1String("QSharedMemory::create"); - switch (errno) { - case EINVAL: - errorString = QSharedMemory::tr("%1: system-imposed size restrictions").arg(QLatin1String("QSharedMemory::handle")); - error = QSharedMemory::InvalidSize; - break; - default: - setErrorString(function); - } - if (createdFile && error != QSharedMemory::AlreadyExists) - QFile::remove(nativeKey); - return false; - } - - return true; -} - -bool QSharedMemoryPrivate::attach(QSharedMemory::AccessMode mode) -{ - // grab the shared memory segment id - int id = shmget(unix_key, 0, (mode == QSharedMemory::ReadOnly ? 0400 : 0600)); - if (-1 == id) { - setErrorString(QLatin1String("QSharedMemory::attach (shmget)")); - return false; - } - - // grab the memory - memory = shmat(id, 0, (mode == QSharedMemory::ReadOnly ? SHM_RDONLY : 0)); - if ((void*) - 1 == memory) { - memory = 0; - setErrorString(QLatin1String("QSharedMemory::attach (shmat)")); - return false; - } - - // grab the size - shmid_ds shmid_ds; - if (!shmctl(id, IPC_STAT, &shmid_ds)) { - size = (int)shmid_ds.shm_segsz; - } else { - setErrorString(QLatin1String("QSharedMemory::attach (shmctl)")); - return false; - } - - return true; -} - -bool QSharedMemoryPrivate::detach() -{ - // detach from the memory segment - if (-1 == shmdt(memory)) { - QString function = QLatin1String("QSharedMemory::detach"); - switch (errno) { - case EINVAL: - errorString = QSharedMemory::tr("%1: not attached").arg(function); - error = QSharedMemory::NotFound; - break; - default: - setErrorString(function); - } - return false; - } - memory = 0; - size = 0; - - // Get the number of current attachments - int id = shmget(unix_key, 0, 0400); - cleanHandle(); - - struct shmid_ds shmid_ds; - if (0 != shmctl(id, IPC_STAT, &shmid_ds)) { - switch (errno) { - case EINVAL: - return true; - default: - return false; - } - } - // If there are no attachments then remove it. - if (shmid_ds.shm_nattch == 0) { - // mark for removal - if (-1 == shmctl(id, IPC_RMID, &shmid_ds)) { - setErrorString(QLatin1String("QSharedMemory::remove")); - switch (errno) { - case EINVAL: - return true; - default: - return false; - } - } - - // remove file - if (!QFile::remove(nativeKey)) - return false; - } - return true; -} - - QT_END_NAMESPACE #endif // QT_NO_SHAREDMEMORY |