diff options
Diffstat (limited to 'indra/llcommon/llevents.h')
| -rw-r--r-- | indra/llcommon/llevents.h | 181 |
1 files changed, 94 insertions, 87 deletions
diff --git a/indra/llcommon/llevents.h b/indra/llcommon/llevents.h index 4bf1fa07a2..d339a09117 100644 --- a/indra/llcommon/llevents.h +++ b/indra/llcommon/llevents.h @@ -32,35 +32,21 @@ #if ! defined(LL_LLEVENTS_H) #define LL_LLEVENTS_H -#include <string> +#include <deque> +#include <functional> #include <map> #include <set> +#include <string> +#include <type_traits> #include <vector> -#include <deque> -#include <functional> #include <boost/signals2.hpp> -#include <boost/bind.hpp> -#include <boost/utility.hpp> // noncopyable #include <boost/optional/optional.hpp> -#include <boost/visit_each.hpp> -#include <boost/ref.hpp> // reference_wrapper -#include <boost/type_traits/is_pointer.hpp> -#include <boost/static_assert.hpp> -#include "llsd.h" -#include "llsingleton.h" +#include "llcoromutex.h" #include "lldependencies.h" -#include "llstl.h" #include "llexception.h" -#include "llhandle.h" -#include "llcoros.h" - -/*==========================================================================*| -// override this to allow binding free functions with more parameters -#ifndef LLEVENTS_LISTENER_ARITY -#define LLEVENTS_LISTENER_ARITY 10 -#endif -|*==========================================================================*/ +#include "llsd.h" +#include "llsingleton.h" // hack for testing #ifndef testable @@ -144,6 +130,12 @@ typedef boost::signals2::signal<bool(const LLSD&), LLStopWhenHandled, float> LL /// Methods that forward listeners (e.g. constructed with /// <tt>boost::bind()</tt>) should accept (const LLEventListener&) typedef LLStandardSignal::slot_type LLEventListener; +/// Support a listener accepting (const LLBoundListener&, const LLSD&). +/// Note that LLBoundListener::disconnect() is a const method: this feature is +/// specifically intended to allow a listener to disconnect itself when done. +typedef LLStandardSignal::extended_slot_type LLAwareListener; +/// Accept a void listener too +typedef std::function<void(const LLSD&)> LLVoidListener; /// Result of registering a listener, supports <tt>connected()</tt>, /// <tt>disconnect()</tt> and <tt>blocked()</tt> typedef boost::signals2::connection LLBoundListener; @@ -218,15 +210,7 @@ class LLEventPump; * LLEventPumps is a Singleton manager through which one typically accesses * this subsystem. */ -// LLEventPumps isa LLHandleProvider only for (hopefully rare) long-lived -// class objects that must refer to this class late in their lifespan, say in -// the destructor. Specifically, the case that matters is a possible reference -// after LLEventPumps::deleteSingleton(). (Lingering LLEventPump instances are -// capable of this.) In that case, instead of calling LLEventPumps::instance() -// again -- resurrecting the deleted LLSingleton -- store an -// LLHandle<LLEventPumps> and test it before use. -class LL_COMMON_API LLEventPumps: public LLSingleton<LLEventPumps>, - public LLHandleProvider<LLEventPumps> +class LL_COMMON_API LLEventPumps: public LLSingleton<LLEventPumps> { LLSINGLETON(LLEventPumps); public: @@ -372,56 +356,13 @@ testable: }; /***************************************************************************** -* LLEventTrackable -*****************************************************************************/ -/** - * LLEventTrackable wraps boost::signals2::trackable, which resembles - * boost::trackable. Derive your listener class from LLEventTrackable instead, - * and use something like - * <tt>LLEventPump::listen(boost::bind(&YourTrackableSubclass::method, - * instance, _1))</tt>. This will implicitly disconnect when the object - * referenced by @c instance is destroyed. - * - * @note - * LLEventTrackable doesn't address a couple of cases: - * * Object destroyed during call - * - You enter a slot call in thread A. - * - Thread B destroys the object, which of course disconnects it from any - * future slot calls. - * - Thread A's call uses 'this', which now refers to a defunct object. - * Undefined behavior results. - * * Call during destruction - * - @c MySubclass is derived from LLEventTrackable. - * - @c MySubclass registers one of its own methods using - * <tt>LLEventPump::listen()</tt>. - * - The @c MySubclass object begins destruction. <tt>~MySubclass()</tt> - * runs, destroying state specific to the subclass. (For instance, a - * <tt>Foo*</tt> data member is <tt>delete</tt>d but not zeroed.) - * - The listening method will not be disconnected until - * <tt>~LLEventTrackable()</tt> runs. - * - Before we get there, another thread posts data to the @c LLEventPump - * instance, calling the @c MySubclass method. - * - The method in question relies on valid @c MySubclass state. (For - * instance, it attempts to dereference the <tt>Foo*</tt> pointer that was - * <tt>delete</tt>d but not zeroed.) - * - Undefined behavior results. - */ -typedef boost::signals2::trackable LLEventTrackable; - -/***************************************************************************** * LLEventPump *****************************************************************************/ /** * LLEventPump is the base class interface through which we access the * concrete subclasses such as LLEventStream. - * - * @NOTE - * LLEventPump derives from LLEventTrackable so that when you "chain" - * LLEventPump instances together, they will automatically disconnect on - * destruction. Please see LLEventTrackable documentation for situations in - * which this may be perilous across threads. */ -class LL_COMMON_API LLEventPump: public LLEventTrackable +class LL_COMMON_API LLEventPump { public: static const std::string ANONYMOUS; // constant for anonymous listeners. @@ -535,18 +476,37 @@ public: * call, allows us to optimize away the second and subsequent dependency * sorts. * - * If name is set to LLEventPump::ANONYMOUS listen will bypass the entire + * If name is set to LLEventPump::ANONYMOUS, listen() will bypass the entire * dependency and ordering calculation. In this case, it is critical that * the result be assigned to a LLTempBoundListener or the listener is - * manually disconnected when no longer needed since there will be no + * manually disconnected when no longer needed, since there will be no * way to later find and disconnect this listener manually. */ + template <typename LISTENER> LLBoundListener listen(const std::string& name, - const LLEventListener& listener, + LISTENER&& listener, const NameList& after=NameList(), const NameList& before=NameList()) { - return listen_impl(name, listener, after, before); + if constexpr (std::is_invocable_v<LISTENER, const LLSD&>) + { + // wrap classic LLEventListener in LLAwareListener lambda + return listenb( + name, + [listener=std::move(listener)] + (const LLBoundListener&, const LLSD& event) + { + return listener(event); + }, + after, + before); + } + else + { + static_assert(std::is_invocable_v<LISTENER, LLBoundListener, const LLSD&>, + "LLEventPump::listen() listener has bad parameter signature"); + return listenb(name, std::forward<LISTENER>(listener), after, before); + } } /// Get the LLBoundListener associated with the passed name (dummy @@ -587,17 +547,40 @@ private: virtual void clear(); virtual void reset(); - - private: - // must precede mName; see LLEventPump::LLEventPump() - LLHandle<LLEventPumps> mRegistry; - std::string mName; - LLCoros::Mutex mConnectionListMutex; + llcoro::Mutex mConnectionListMutex; protected: - virtual LLBoundListener listen_impl(const std::string& name, const LLEventListener&, + template <typename LISTENER> + LLBoundListener listenb(const std::string& name, + LISTENER&& listener, + const NameList& after=NameList(), + const NameList& before=NameList()) + { + using result_t = std::decay_t<decltype(listener(LLBoundListener(), LLSD()))>; + if constexpr (std::is_same_v<bool, result_t>) + { + return listen_impl(name, std::forward<LISTENER>(listener), after, before); + } + else + { + static_assert(std::is_same_v<void, result_t>, + "LLEventPump::listen() listener has bad return type"); + // wrap void listener in one that returns bool + return listen_impl( + name, + [listener=std::move(listener)] + (const LLBoundListener& conn, const LLSD& event) + { + listener(conn, event); + return false; + }, + after, + before); + } + } + virtual LLBoundListener listen_impl(const std::string& name, const LLAwareListener&, const NameList& after, const NameList& before); @@ -672,7 +655,7 @@ public: void discard(); protected: - virtual LLBoundListener listen_impl(const std::string& name, const LLEventListener&, + virtual LLBoundListener listen_impl(const std::string& name, const LLAwareListener&, const NameList& after, const NameList& before) override; @@ -682,6 +665,30 @@ private: }; /***************************************************************************** +* LLNamedListener +*****************************************************************************/ +/** + * LLNamedListener bundles a concrete LLEventPump subclass with a specific + * listener function, with an LLTempBoundListener to ensure that it's + * disconnected before destruction. + */ +template <class PUMP=LLEventStream> +class LL_COMMON_API LLNamedListener: PUMP +{ + using pump_t = PUMP; +public: + template <typename LISTENER> + LLNamedListener(const std::string& name, LISTENER&& listener): + pump_t(name, false), // don't tweak the name + mConn(pump_t::listen("func", std::forward<LISTENER>(listener))) + {} + +private: + LLTempBoundListener mConn; +}; +using LLStreamListener = LLNamedListener<>; + +/***************************************************************************** * LLReqID *****************************************************************************/ /** @@ -773,7 +780,7 @@ private: * Before sending the reply event, sendReply() copies the ["reqid"] item from * the request to the reply. */ -LL_COMMON_API bool sendReply(const LLSD& reply, const LLSD& request, +LL_COMMON_API bool sendReply(LLSD reply, const LLSD& request, const std::string& replyKey="reply"); #endif /* ! defined(LL_LLEVENTS_H) */ |