diff options
| -rw-r--r-- | src/libcamera/signal.cpp | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/src/libcamera/signal.cpp b/src/libcamera/signal.cpp index 9bb7eca8..6eab1fa7 100644 --- a/src/libcamera/signal.cpp +++ b/src/libcamera/signal.cpp @@ -7,6 +7,8 @@ #include <libcamera/signal.h> +#include "thread.h" + /** * \file signal.h * \brief Signal & slot implementation @@ -14,8 +16,21 @@ namespace libcamera { +namespace { + +/* + * Mutex to protect the SignalBase::slots_ and Object::signals_ lists. If lock + * contention needs to be decreased, this could be replaced with locks in + * Object and SignalBase, or with a mutex pool. + */ +Mutex signalsLock; + +} /* namespace */ + void SignalBase::connect(BoundMethodBase *slot) { + MutexLocker locker(signalsLock); + Object *object = slot->object(); if (object) object->connect(this); @@ -31,6 +46,8 @@ void SignalBase::disconnect(Object *object) void SignalBase::disconnect(std::function<bool(SlotList::iterator &)> match) { + MutexLocker locker(signalsLock); + for (auto iter = slots_.begin(); iter != slots_.end(); ) { if (match(iter)) { Object *object = (*iter)->object(); @@ -47,6 +64,7 @@ void SignalBase::disconnect(std::function<bool(SlotList::iterator &)> match) SignalBase::SlotList SignalBase::slots() { + MutexLocker locker(signalsLock); return slots_; } @@ -99,23 +117,31 @@ SignalBase::SlotList SignalBase::slots() * disconnected from the \a func slot of \a object when \a object is destroyed. * Otherwise the caller shall disconnect signals manually before destroying \a * object. + * + * \context This function is \threadsafe. */ /** * \fn Signal::connect(R (*func)(Args...)) * \brief Connect the signal to a static function slot * \param[in] func The slot static function + * + * \context This function is \threadsafe. */ /** * \fn Signal::disconnect() * \brief Disconnect the signal from all slots + * + * \context This function is \threadsafe. */ /** * \fn Signal::disconnect(T *object) * \brief Disconnect the signal from all slots of the \a object * \param[in] object The object pointer whose slots to disconnect + * + * \context This function is \threadsafe. */ /** @@ -123,12 +149,16 @@ SignalBase::SlotList SignalBase::slots() * \brief Disconnect the signal from the \a object slot member function \a func * \param[in] object The object pointer whose slots to disconnect * \param[in] func The slot member function to disconnect + * + * \context This function is \threadsafe. */ /** * \fn Signal::disconnect(R (*func)(Args...)) * \brief Disconnect the signal from the slot static function \a func * \param[in] func The slot static function to disconnect + * + * \context This function is \threadsafe. */ /** @@ -141,6 +171,9 @@ SignalBase::SlotList SignalBase::slots() * function are passed to the slot functions unchanged. If a slot modifies one * of the arguments (when passed by pointer or reference), the modification is * thus visible to all subsequently called slots. + * + * This function is not \threadsafe, but thread-safety is guaranteed against + * concurrent connect() and disconnect() calls. */ } /* namespace libcamera */ |