diff options
Diffstat (limited to 'src/gui/embedded/qlock.cpp')
| -rw-r--r-- | src/gui/embedded/qlock.cpp | 128 |
1 files changed, 111 insertions, 17 deletions
diff --git a/src/gui/embedded/qlock.cpp b/src/gui/embedded/qlock.cpp index ac15431..eaad15c 100644 --- a/src/gui/embedded/qlock.cpp +++ b/src/gui/embedded/qlock.cpp @@ -41,7 +41,6 @@ #include "qlock_p.h" - #ifdef QT_NO_QWS_MULTIPROCESS QT_BEGIN_NAMESPACE @@ -83,7 +82,7 @@ QT_END_NAMESPACE #else // QT_NO_QWS_MULTIPROCESS #if defined(Q_OS_DARWIN) -# define Q_NO_SEMAPHORE +# define QT_NO_SEMAPHORE #endif #include "qwssignalhandler_p.h" @@ -91,11 +90,13 @@ QT_END_NAMESPACE #include <unistd.h> #include <sys/types.h> #include <sys/ipc.h> -#if defined(Q_NO_SEMAPHORE) +#if defined(QT_NO_SEMAPHORE) # include <sys/stat.h> # include <sys/file.h> -#else +#elif !defined(QT_POSIX_IPC) # include <sys/sem.h> +#else +# include <semaphore.h> #endif #include <string.h> #include <errno.h> @@ -109,17 +110,24 @@ QT_BEGIN_NAMESPACE class QLockData { public: -#ifdef Q_NO_SEMAPHORE +#if defined(QT_NO_SEMAPHORE) || defined(QT_POSIX_IPC) QByteArray file; -#endif // Q_NO_SEMAPHORE +#endif +#if !defined(QT_POSIX_IPC) int id; +#else + sem_t *id; // Read mode resource counter + sem_t *rsem; // Read mode lock + sem_t *wsem; // Write mode lock +#endif int count; bool owned; }; + /*! \class QLock - \brief The QLock class is a wrapper for a System V shared semaphore. + \brief The QLock class is a wrapper for a system shared semaphore. \ingroup qws @@ -148,7 +156,7 @@ QLock::QLock(const QString &filename, char id, bool create) { data = new QLockData; data->count = 0; -#ifdef Q_NO_SEMAPHORE +#if defined(QT_NO_SEMAPHORE) data->file = filename.toLocal8Bit() + id; for (int x = 0; x < 2; ++x) { data->id = QT_OPEN(data->file.constData(), O_RDWR | (x ? O_CREAT : 0), S_IRWXU); @@ -157,7 +165,7 @@ QLock::QLock(const QString &filename, char id, bool create) break; } } -#else +#elif !defined(QT_POSIX_IPC) key_t semkey = ftok(filename.toLocal8Bit().constData(), id); data->id = semget(semkey, 0, 0); data->owned = create; @@ -170,6 +178,28 @@ QLock::QLock(const QString &filename, char id, bool create) arg.val = MAX_LOCKS; semctl(data->id, 0, SETVAL, arg); } +#else + data->file = filename.toLocal8Bit() + id; + data->owned = create; + + char ids[3] = { 'c', 'r', 'w' }; + sem_t **sems[3] = { &data->id, &data->rsem, &data->wsem }; + unsigned short initialValues[3] = { MAX_LOCKS, 1, 1 }; + for (int i = 0; i < 3; ++i) { + QByteArray file = data->file + ids[i]; + do { + *sems[i] = sem_open(file.constData(), 0, 0666, 0); + } while (*sems[i] == SEM_FAILED && errno == EINTR); + if (create) { + if (*sems[i] != SEM_FAILED) { + sem_close(*sems[i]); + sem_unlink(file.constData()); + } + do { + *sems[i] = sem_open(file.constData(), O_CREAT, 0666, initialValues[i]); + } while (*sems[i] == SEM_FAILED && errno == EINTR); + } + } #endif if (!isValid()) { qWarning("QLock::QLock: Cannot %s semaphore %s '%c' (%d, %s)", @@ -193,17 +223,32 @@ QLock::~QLock() while (locked()) unlock(); -#ifdef Q_NO_SEMAPHORE + +#if defined(QT_NO_SEMAPHORE) if (isValid()) QT_CLOSE(data->id); +#elif defined(QT_POSIX_IPC) + if (data->id != SEM_FAILED) + sem_close(data->id); + if (data->rsem != SEM_FAILED) + sem_close(data->rsem); + if (data->wsem != SEM_FAILED) + sem_close(data->wsem); #endif + if (data->owned) { -#ifdef Q_NO_SEMAPHORE +#if defined(QT_NO_SEMAPHORE) unlink(data->file.constData()); -#else +#elif !defined(QT_POSIX_IPC) qt_semun semval; semval.val = 0; semctl(data->id, 0, IPC_RMID, semval); +#else + char ids[3] = { 'c', 'r', 'w' }; + for (int i = 0; i < 3; ++i) { + QByteArray file = data->file + ids[i]; + sem_unlink(file.constData()); + } #endif } delete data; @@ -216,7 +261,11 @@ QLock::~QLock() */ bool QLock::isValid() const { +#if !defined(QT_POSIX_IPC) return data && data->id != -1; +#else + return data && data->id != SEM_FAILED && data->rsem != SEM_FAILED && data->wsem != SEM_FAILED; +#endif } /*! @@ -232,21 +281,48 @@ bool QLock::isValid() const */ void QLock::lock(Type t) { + if (!isValid()) + return; + if (!data->count) { type = t; int rv; -#ifdef Q_NO_SEMAPHORE +#if defined(QT_NO_SEMAPHORE) int op = type == Write ? LOCK_EX : LOCK_SH; EINTR_LOOP(rv, flock(data->id, op)); -#else +#elif !defined(QT_POSIX_IPC) sembuf sops; sops.sem_num = 0; sops.sem_op = type == Write ? -MAX_LOCKS : -1; sops.sem_flg = SEM_UNDO; EINTR_LOOP(rv, semop(data->id, &sops, 1)); +#else + if (type == Write) { + EINTR_LOOP(rv, sem_wait(data->rsem)); + if (rv != -1) { + EINTR_LOOP(rv, sem_wait(data->wsem)); + if (rv == -1) + sem_post(data->rsem); + } + } else { + EINTR_LOOP(rv, sem_wait(data->wsem)); + if (rv != -1) { + EINTR_LOOP(rv, sem_trywait(data->rsem)); + if (rv != -1 || errno == EAGAIN) { + EINTR_LOOP(rv, sem_wait(data->id)); + if (rv == -1) { + int semval; + sem_getvalue(data->id, &semval); + if (semval == MAX_LOCKS) + sem_post(data->rsem); + } + } + rv = sem_post(data->wsem); + } + } #endif if (rv == -1) { qDebug("QLock::lock(): %s", strerror(errno)); @@ -265,19 +341,37 @@ void QLock::lock(Type t) */ void QLock::unlock() { - if (data->count) { + if (!isValid()) + return; + + if (data->count > 0) { data->count--; if (!data->count) { int rv; -#ifdef Q_NO_SEMAPHORE +#if defined(QT_NO_SEMAPHORE) EINTR_LOOP(rv, flock(data->id, LOCK_UN)); -#else +#elif !defined(QT_POSIX_IPC) sembuf sops; sops.sem_num = 0; sops.sem_op = type == Write ? MAX_LOCKS : 1; sops.sem_flg = SEM_UNDO; EINTR_LOOP(rv, semop(data->id, &sops, 1)); +#else + if (type == Write) { + sem_post(data->wsem); + rv = sem_post(data->rsem); + } else { + EINTR_LOOP(rv, sem_wait(data->wsem)); + if (rv != -1) { + sem_post(data->id); + int semval; + sem_getvalue(data->id, &semval); + if (semval == MAX_LOCKS) + sem_post(data->rsem); + rv = sem_post(data->wsem); + } + } #endif if (rv == -1) qDebug("QLock::unlock(): %s", strerror(errno)); |