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-rw-r--r--indra/llcommon/CMakeLists.txt3
-rw-r--r--indra/llcommon/llapp.cpp3
-rw-r--r--indra/llcommon/llcleanup.h30
-rw-r--r--indra/llcommon/llcommon.cpp5
-rw-r--r--indra/llcommon/llerror.cpp26
-rw-r--r--indra/llcommon/llerror.h1
-rw-r--r--indra/llcommon/llerrorcontrol.h5
-rw-r--r--indra/llcommon/llinitdestroyclass.h190
-rw-r--r--indra/llcommon/llpounceable.h215
-rw-r--r--indra/llcommon/llregistry.h2
-rw-r--r--indra/llcommon/llsingleton.cpp327
-rw-r--r--indra/llcommon/llsingleton.h532
-rw-r--r--indra/llcommon/tests/llpounceable_test.cpp230
-rw-r--r--indra/llcommon/tests/llsingleton_test.cpp206
14 files changed, 1559 insertions, 216 deletions
diff --git a/indra/llcommon/CMakeLists.txt b/indra/llcommon/CMakeLists.txt
index 907dbab8f8..556f879634 100644
--- a/indra/llcommon/CMakeLists.txt
+++ b/indra/llcommon/CMakeLists.txt
@@ -167,6 +167,7 @@ set(llcommon_HEADER_FILES
llhash.h
llheartbeat.h
llindexedvector.h
+ llinitdestroyclass.h
llinitparam.h
llinstancetracker.h
llkeythrottle.h
@@ -183,6 +184,7 @@ set(llcommon_HEADER_FILES
llmortician.h
llnametable.h
llpointer.h
+ llpounceable.h
llpredicate.h
llpreprocessor.h
llpriqueuemap.h
@@ -327,6 +329,7 @@ if (LL_TESTS)
LL_ADD_INTEGRATION_TEST(llprocess "" "${test_libs}")
LL_ADD_INTEGRATION_TEST(llleap "" "${test_libs}")
LL_ADD_INTEGRATION_TEST(llstreamqueue "" "${test_libs}")
+ LL_ADD_INTEGRATION_TEST(llpounceable "" "${test_libs}")
# *TODO - reenable these once tcmalloc libs no longer break the build.
#ADD_BUILD_TEST(llallocator llcommon)
diff --git a/indra/llcommon/llapp.cpp b/indra/llcommon/llapp.cpp
index eb0699ad41..2c76f29020 100644
--- a/indra/llcommon/llapp.cpp
+++ b/indra/llcommon/llapp.cpp
@@ -48,6 +48,7 @@
#include "lleventtimer.h"
#include "google_breakpad/exception_handler.h"
#include "stringize.h"
+#include "llcleanup.h"
//
// Signal handling
@@ -177,7 +178,7 @@ LLApp::~LLApp()
if(mExceptionHandler != 0) delete mExceptionHandler;
- LLCommon::cleanupClass();
+ SUBSYSTEM_CLEANUP(LLCommon);
}
// static
diff --git a/indra/llcommon/llcleanup.h b/indra/llcommon/llcleanup.h
new file mode 100644
index 0000000000..8eda9a7fb3
--- /dev/null
+++ b/indra/llcommon/llcleanup.h
@@ -0,0 +1,30 @@
+/**
+ * @file llcleanup.h
+ * @author Nat Goodspeed
+ * @date 2015-05-20
+ * @brief Mechanism for cleaning up subsystem resources
+ *
+ * $LicenseInfo:firstyear=2015&license=viewerlgpl$
+ * Copyright (c) 2015, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLCLEANUP_H)
+#define LL_LLCLEANUP_H
+
+#include "llerror.h"
+
+// Instead of directly calling SomeClass::cleanupClass(), use
+// SUBSYSTEM_CLEANUP(SomeClass);
+// This logs the call as well as performing it. That gives us a baseline
+// subsystem shutdown order against which to compare subsequent dynamic
+// shutdown schemes.
+#define SUBSYSTEM_CLEANUP(CLASSNAME) \
+ do { \
+ LL_INFOS("Cleanup") << "Calling " #CLASSNAME "::cleanupClass()" << LL_ENDL; \
+ CLASSNAME::cleanupClass(); \
+ } while (0)
+// Use ancient do { ... } while (0) macro trick to permit a block of
+// statements with the same syntax as a single statement.
+
+#endif /* ! defined(LL_LLCLEANUP_H) */
diff --git a/indra/llcommon/llcommon.cpp b/indra/llcommon/llcommon.cpp
index 19642b0982..439ff4e628 100644
--- a/indra/llcommon/llcommon.cpp
+++ b/indra/llcommon/llcommon.cpp
@@ -31,6 +31,7 @@
#include "llthread.h"
#include "lltrace.h"
#include "lltracethreadrecorder.h"
+#include "llcleanup.h"
//static
BOOL LLCommon::sAprInitialized = FALSE;
@@ -63,11 +64,11 @@ void LLCommon::cleanupClass()
sMasterThreadRecorder = NULL;
LLTrace::set_master_thread_recorder(NULL);
LLThreadSafeRefCount::cleanupThreadSafeRefCount();
- LLTimer::cleanupClass();
+ SUBSYSTEM_CLEANUP(LLTimer);
if (sAprInitialized)
{
ll_cleanup_apr();
sAprInitialized = FALSE;
}
- LLMemory::cleanupClass();
+ SUBSYSTEM_CLEANUP(LLMemory);
}
diff --git a/indra/llcommon/llerror.cpp b/indra/llcommon/llerror.cpp
index 5ed348e13c..638cecb054 100644
--- a/indra/llcommon/llerror.cpp
+++ b/indra/llcommon/llerror.cpp
@@ -239,6 +239,14 @@ namespace
{
std::string className(const std::type_info& type)
{
+ return LLError::Log::demangle(type.name());
+ }
+} // anonymous
+
+namespace LLError
+{
+ std::string Log::demangle(const char* mangled)
+ {
#ifdef __GNUC__
// GCC: type_info::name() returns a mangled class name,st demangle
@@ -252,18 +260,18 @@ namespace
// but gcc 3.3 libstc++'s implementation of demangling is broken
// and fails without.
- char* name = abi::__cxa_demangle(type.name(),
+ char* name = abi::__cxa_demangle(mangled,
abi_name_buf, &abi_name_len, &status);
// this call can realloc the abi_name_buf pointer (!)
- return name ? name : type.name();
+ return name ? name : mangled;
#elif LL_WINDOWS
// DevStudio: type_info::name() includes the text "class " at the start
static const std::string class_prefix = "class ";
- std::string name = type.name();
+ std::string name = mangled;
std::string::size_type p = name.find(class_prefix);
if (p == std::string::npos)
{
@@ -272,11 +280,14 @@ namespace
return name.substr(p + class_prefix.size());
-#else
- return type.name();
+#else
+ return mangled;
#endif
}
+} // LLError
+namespace
+{
std::string functionName(const std::string& preprocessor_name)
{
#if LL_WINDOWS
@@ -403,6 +414,11 @@ namespace
namespace LLError
{
+ bool is_available()
+ {
+ return Globals::instanceExists();
+ }
+
class SettingsConfig : public LLRefCount
{
friend class Settings;
diff --git a/indra/llcommon/llerror.h b/indra/llcommon/llerror.h
index 3beef65723..b3b18fdf03 100644
--- a/indra/llcommon/llerror.h
+++ b/indra/llcommon/llerror.h
@@ -189,6 +189,7 @@ namespace LLError
static std::ostringstream* out();
static void flush(std::ostringstream* out, char* message);
static void flush(std::ostringstream*, const CallSite&);
+ static std::string demangle(const char* mangled);
};
struct LL_COMMON_API CallSite
diff --git a/indra/llcommon/llerrorcontrol.h b/indra/llcommon/llerrorcontrol.h
index 56ac52e5de..56e84f7172 100644
--- a/indra/llcommon/llerrorcontrol.h
+++ b/indra/llcommon/llerrorcontrol.h
@@ -189,6 +189,11 @@ namespace LLError
LL_COMMON_API std::string abbreviateFile(const std::string& filePath);
LL_COMMON_API int shouldLogCallCount();
+
+ // Check whether Globals exists. This should only be used by LLSingleton
+ // infrastructure to avoid trying to log when our internal LLSingleton is
+ // unavailable -- circularity ensues.
+ LL_COMMON_API bool is_available();
};
#endif // LL_LLERRORCONTROL_H
diff --git a/indra/llcommon/llinitdestroyclass.h b/indra/llcommon/llinitdestroyclass.h
new file mode 100644
index 0000000000..49bcefc33d
--- /dev/null
+++ b/indra/llcommon/llinitdestroyclass.h
@@ -0,0 +1,190 @@
+/**
+ * @file llinitdestroyclass.h
+ * @author Nat Goodspeed
+ * @date 2015-05-27
+ * @brief LLInitClass / LLDestroyClass mechanism
+ *
+ * The LLInitClass template, extracted from llui.h, ensures that control will
+ * reach a static initClass() method. LLDestroyClass does the same for a
+ * static destroyClass() method.
+ *
+ * The distinguishing characteristics of these templates are:
+ *
+ * - All LLInitClass<T>::initClass() methods are triggered by an explicit call
+ * to LLInitClassList::instance().fireCallbacks(). Presumably this call
+ * happens sometime after all static objects in the program have been
+ * initialized. In other words, each LLInitClass<T>::initClass() method
+ * should be able to make some assumptions about global program state.
+ *
+ * - Similarly, LLDestroyClass<T>::destroyClass() methods are triggered by
+ * LLDestroyClassList::instance().fireCallbacks(). Again, presumably this
+ * happens at a well-defined moment in the program's shutdown sequence.
+ *
+ * - The initClass() calls happen in an unspecified sequence. You may not rely
+ * on the relative ordering of LLInitClass<T>::initClass() versus another
+ * LLInitClass<U>::initClass() method. If you need such a guarantee, use
+ * LLSingleton instead and make the dependency explicit.
+ *
+ * - Similarly, LLDestroyClass<T>::destroyClass() may happen either before or
+ * after LLDestroyClass<U>::destroyClass(). You cannot rely on that order.
+ *
+ * $LicenseInfo:firstyear=2015&license=viewerlgpl$
+ * Copyright (c) 2015, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLINITDESTROYCLASS_H)
+#define LL_LLINITDESTROYCLASS_H
+
+#include "llerror.h"
+#include "llsingleton.h"
+#include <boost/function.hpp>
+#include <boost/signals2/signal.hpp>
+#include <typeinfo>
+
+/**
+ * LLCallbackRegistry is an implementation detail base class for
+ * LLInitClassList and LLDestroyClassList. It's a very thin wrapper around a
+ * Boost.Signals2 signal object.
+ */
+class LLCallbackRegistry
+{
+public:
+ typedef boost::signals2::signal<void()> callback_signal_t;
+
+ void registerCallback(const callback_signal_t::slot_type& slot)
+ {
+ mCallbacks.connect(slot);
+ }
+
+ void fireCallbacks()
+ {
+ mCallbacks();
+ }
+
+private:
+ callback_signal_t mCallbacks;
+};
+
+/**
+ * LLInitClassList is the LLCallbackRegistry for LLInitClass. It stores the
+ * registered initClass() methods. It must be an LLSingleton because
+ * LLInitClass registers its initClass() method at static construction time
+ * (before main()), requiring LLInitClassList to be fully constructed on
+ * demand regardless of module initialization order.
+ */
+class LLInitClassList :
+ public LLCallbackRegistry,
+ public LLSingleton<LLInitClassList>
+{
+ friend class LLSingleton<LLInitClassList>;
+private:
+ LLInitClassList() {}
+};
+
+/**
+ * LLDestroyClassList is the LLCallbackRegistry for LLDestroyClass. It stores
+ * the registered destroyClass() methods. It must be an LLSingleton because
+ * LLDestroyClass registers its destroyClass() method at static construction
+ * time (before main()), requiring LLDestroyClassList to be fully constructed
+ * on demand regardless of module initialization order.
+ */
+class LLDestroyClassList :
+ public LLCallbackRegistry,
+ public LLSingleton<LLDestroyClassList>
+{
+ friend class LLSingleton<LLDestroyClassList>;
+private:
+ LLDestroyClassList() {}
+};
+
+/**
+ * LLRegisterWith is an implementation detail for LLInitClass and
+ * LLDestroyClass. It is intended to be used as a static class member whose
+ * constructor registers the specified callback with the LLMumbleClassList
+ * singleton registry specified as the template argument.
+ */
+template<typename T>
+class LLRegisterWith
+{
+public:
+ LLRegisterWith(boost::function<void ()> func)
+ {
+ T::instance().registerCallback(func);
+ }
+
+ // this avoids a MSVC bug where non-referenced static members are "optimized" away
+ // even if their constructors have side effects
+ S32 reference()
+ {
+ S32 dummy;
+ dummy = 0;
+ return dummy;
+ }
+};
+
+/**
+ * Derive MyClass from LLInitClass<MyClass> (the Curiously Recurring Template
+ * Pattern) to ensure that the static method MyClass::initClass() will be
+ * called (along with all other LLInitClass<T> subclass initClass() methods)
+ * when someone calls LLInitClassList::instance().fireCallbacks(). This gives
+ * the application specific control over the timing of all such
+ * initializations, without having to insert calls for every such class into
+ * generic application code.
+ */
+template<typename T>
+class LLInitClass
+{
+public:
+ LLInitClass() { sRegister.reference(); }
+
+ // When this static member is initialized, the subclass initClass() method
+ // is registered on LLInitClassList. See sRegister definition below.
+ static LLRegisterWith<LLInitClassList> sRegister;
+private:
+
+ // Provide a default initClass() method in case subclass misspells (or
+ // omits) initClass(). This turns a potential build error into a fatal
+ // runtime error.
+ static void initClass()
+ {
+ LL_ERRS() << "No static initClass() method defined for " << typeid(T).name() << LL_ENDL;
+ }
+};
+
+/**
+ * Derive MyClass from LLDestroyClass<MyClass> (the Curiously Recurring
+ * Template Pattern) to ensure that the static method MyClass::destroyClass()
+ * will be called (along with other LLDestroyClass<T> subclass destroyClass()
+ * methods) when someone calls LLDestroyClassList::instance().fireCallbacks().
+ * This gives the application specific control over the timing of all such
+ * cleanup calls, without having to insert calls for every such class into
+ * generic application code.
+ */
+template<typename T>
+class LLDestroyClass
+{
+public:
+ LLDestroyClass() { sRegister.reference(); }
+
+ // When this static member is initialized, the subclass destroyClass()
+ // method is registered on LLInitClassList. See sRegister definition
+ // below.
+ static LLRegisterWith<LLDestroyClassList> sRegister;
+private:
+
+ // Provide a default destroyClass() method in case subclass misspells (or
+ // omits) destroyClass(). This turns a potential build error into a fatal
+ // runtime error.
+ static void destroyClass()
+ {
+ LL_ERRS() << "No static destroyClass() method defined for " << typeid(T).name() << LL_ENDL;
+ }
+};
+
+// Here's where LLInitClass<T> specifies the subclass initClass() method.
+template <typename T> LLRegisterWith<LLInitClassList> LLInitClass<T>::sRegister(&T::initClass);
+// Here's where LLDestroyClass<T> specifies the subclass destroyClass() method.
+template <typename T> LLRegisterWith<LLDestroyClassList> LLDestroyClass<T>::sRegister(&T::destroyClass);
+
+#endif /* ! defined(LL_LLINITDESTROYCLASS_H) */
diff --git a/indra/llcommon/llpounceable.h b/indra/llcommon/llpounceable.h
new file mode 100644
index 0000000000..77b711bdc6
--- /dev/null
+++ b/indra/llcommon/llpounceable.h
@@ -0,0 +1,215 @@
+/**
+ * @file llpounceable.h
+ * @author Nat Goodspeed
+ * @date 2015-05-22
+ * @brief LLPounceable is tangentially related to a future: it's a holder for
+ * a value that may or may not exist yet. Unlike a future, though,
+ * LLPounceable freely allows reading the held value. (If the held
+ * type T does not have a distinguished "empty" value, consider using
+ * LLPounceable<boost::optional<T>>.)
+ *
+ * LLPounceable::callWhenReady() is this template's claim to fame. It
+ * allows its caller to "pounce" on the held value as soon as it
+ * becomes non-empty. Call callWhenReady() with any C++ callable
+ * accepting T. If the held value is already non-empty, callWhenReady()
+ * will immediately call the callable with the held value. If the held
+ * value is empty, though, callWhenReady() will enqueue the callable
+ * for later. As soon as LLPounceable is assigned a non-empty held
+ * value, it will flush the queue of deferred callables.
+ *
+ * Consider a global LLMessageSystem* gMessageSystem. Message system
+ * initialization happens at a very specific point during viewer
+ * initialization. Other subsystems want to register callbacks on the
+ * LLMessageSystem instance as soon as it's initialized, but their own
+ * initialization may precede that. If we define gMessageSystem to be
+ * an LLPounceable<LLMessageSystem*>, a subsystem can use
+ * callWhenReady() to either register immediately (if gMessageSystem
+ * is already up and runnning) or register as soon as gMessageSystem
+ * is set with a new, initialized instance.
+ *
+ * $LicenseInfo:firstyear=2015&license=viewerlgpl$
+ * Copyright (c) 2015, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLPOUNCEABLE_H)
+#define LL_LLPOUNCEABLE_H
+
+#include "llsingleton.h"
+#include <boost/noncopyable.hpp>
+#include <boost/call_traits.hpp>
+#include <boost/type_traits/remove_pointer.hpp>
+#include <boost/utility/value_init.hpp>
+#include <boost/unordered_map.hpp>
+#include <boost/signals2/signal.hpp>
+
+// Forward declare the user template, since we want to be able to point to it
+// in some of its implementation classes.
+template <typename T, class TAG>
+class LLPounceable;
+
+template <typename T, typename TAG>
+struct LLPounceableTraits
+{
+ // Our "queue" is a signal object with correct signature.
+ typedef boost::signals2::signal<void (typename boost::call_traits<T>::param_type)> signal_t;
+ // Call callWhenReady() with any callable accepting T.
+ typedef typename signal_t::slot_type func_t;
+ // owner pointer type
+ typedef LLPounceable<T, TAG>* owner_ptr;
+};
+
+// Tag types distinguish the two different implementations of LLPounceable's
+// queue.
+struct LLPounceableQueue {};
+struct LLPounceableStatic {};
+
+// generic LLPounceableQueueImpl deliberately omitted: only the above tags are
+// legal
+template <typename T, class TAG>
+class LLPounceableQueueImpl;
+
+// The implementation selected by LLPounceableStatic uses an LLSingleton
+// because we can't count on a data member queue being initialized at the time
+// we start getting callWhenReady() calls. This is that LLSingleton.
+template <typename T>
+class LLPounceableQueueSingleton:
+ public LLSingleton<LLPounceableQueueSingleton<T> >
+{
+private:
+ typedef LLPounceableTraits<T, LLPounceableStatic> traits;
+ typedef typename traits::owner_ptr owner_ptr;
+ typedef typename traits::signal_t signal_t;
+
+ // For a given held type T, every LLPounceable<T, LLPounceableStatic>
+ // instance will call on the SAME LLPounceableQueueSingleton instance --
+ // given how class statics work. We must keep a separate queue for each
+ // LLPounceable instance. Use a hash map for that.
+ typedef boost::unordered_map<owner_ptr, signal_t> map_t;
+
+public:
+ // Disambiguate queues belonging to different LLPounceables.
+ signal_t& get(owner_ptr owner)
+ {
+ // operator[] has find-or-create semantics -- just what we want!
+ return mMap[owner];
+ }
+
+private:
+ map_t mMap;
+};
+
+// LLPounceableQueueImpl that uses the above LLSingleton
+template <typename T>
+class LLPounceableQueueImpl<T, LLPounceableStatic>
+{
+public:
+ typedef LLPounceableTraits<T, LLPounceableStatic> traits;
+ typedef typename traits::owner_ptr owner_ptr;
+ typedef typename traits::signal_t signal_t;
+
+ signal_t& get(owner_ptr owner) const
+ {
+ // this Impl contains nothing; it delegates to the Singleton
+ return LLPounceableQueueSingleton<T>::instance().get(owner);
+ }
+};
+
+// The implementation selected by LLPounceableQueue directly contains the
+// queue of interest, suitable for an LLPounceable we can trust to be fully
+// initialized when it starts getting callWhenReady() calls.
+template <typename T>
+class LLPounceableQueueImpl<T, LLPounceableQueue>
+{
+public:
+ typedef LLPounceableTraits<T, LLPounceableQueue> traits;
+ typedef typename traits::owner_ptr owner_ptr;
+ typedef typename traits::signal_t signal_t;
+
+ signal_t& get(owner_ptr)
+ {
+ return mQueue;
+ }
+
+private:
+ signal_t mQueue;
+};
+
+// LLPounceable<T> is for an LLPounceable instance on the heap or the stack.
+// LLPounceable<T, LLPounceableStatic> is for a static LLPounceable instance.
+template <typename T, class TAG=LLPounceableQueue>
+class LLPounceable: public boost::noncopyable
+{
+private:
+ typedef LLPounceableTraits<T, TAG> traits;
+ typedef typename traits::owner_ptr owner_ptr;
+ typedef typename traits::signal_t signal_t;
+
+public:
+ typedef typename traits::func_t func_t;
+
+ // By default, both the initial value and the distinguished empty value
+ // are a default-constructed T instance. However you can explicitly
+ // specify each.
+ LLPounceable(typename boost::call_traits<T>::value_type init =boost::value_initialized<T>(),
+ typename boost::call_traits<T>::param_type empty=boost::value_initialized<T>()):
+ mHeld(init),
+ mEmpty(empty)
+ {}
+
+ // make read access to mHeld as cheap and transparent as possible
+ operator T () const { return mHeld; }
+ typename boost::remove_pointer<T>::type operator*() const { return *mHeld; }
+ typename boost::call_traits<T>::value_type operator->() const { return mHeld; }
+ // uncomment 'explicit' as soon as we allow C++11 compilation
+ /*explicit*/ operator bool() const { return bool(mHeld); }
+ bool operator!() const { return ! mHeld; }
+
+ // support both assignment (dumb ptr idiom) and reset() (smart ptr)
+ void operator=(typename boost::call_traits<T>::param_type value)
+ {
+ reset(value);
+ }
+
+ void reset(typename boost::call_traits<T>::param_type value)
+ {
+ mHeld = value;
+ // If this new value is non-empty, flush anything pending in the queue.
+ if (mHeld != mEmpty)
+ {
+ signal_t& signal(get_signal());
+ signal(mHeld);
+ signal.disconnect_all_slots();
+ }
+ }
+
+ // our claim to fame
+ void callWhenReady(const func_t& func)
+ {
+ if (mHeld != mEmpty)
+ {
+ // If the held value is already non-empty, immediately call func()
+ func(mHeld);
+ }
+ else
+ {
+ // Held value still empty, queue func() for later. By default,
+ // connect() enqueues slots in FIFO order.
+ get_signal().connect(func);
+ }
+ }
+
+private:
+ signal_t& get_signal() { return mQueue.get(this); }
+
+ // Store both the current and the empty value.
+ // MAYBE: Might be useful to delegate to LLPounceableTraits the meaning of
+ // testing for "empty." For some types we want operator!(); for others we
+ // want to compare to a distinguished value.
+ typename boost::call_traits<T>::value_type mHeld, mEmpty;
+ // This might either contain the queue (LLPounceableQueue) or delegate to
+ // an LLSingleton (LLPounceableStatic).
+ LLPounceableQueueImpl<T, TAG> mQueue;
+};
+
+#endif /* ! defined(LL_LLPOUNCEABLE_H) */
diff --git a/indra/llcommon/llregistry.h b/indra/llcommon/llregistry.h
index 29950c108d..fde729f8f9 100644
--- a/indra/llcommon/llregistry.h
+++ b/indra/llcommon/llregistry.h
@@ -269,7 +269,7 @@ public:
~ScopedRegistrar()
{
- if (!singleton_t::destroyed())
+ if (singleton_t::instanceExists())
{
popScope();
}
diff --git a/indra/llcommon/llsingleton.cpp b/indra/llcommon/llsingleton.cpp
index 9b49e52377..b78110296f 100644
--- a/indra/llcommon/llsingleton.cpp
+++ b/indra/llcommon/llsingleton.cpp
@@ -25,7 +25,332 @@
*/
#include "linden_common.h"
-
#include "llsingleton.h"
+#include "llerror.h"
+#include "llerrorcontrol.h" // LLError::is_available()
+#include "lldependencies.h"
+#include <boost/foreach.hpp>
+#include <algorithm>
+#include <iostream> // std::cerr in dire emergency
+#include <sstream>
+#include <stdexcept>
+
+// Our master list of all LLSingletons is itself an LLSingleton. We used to
+// store it in a function-local static, but that could get destroyed before
+// the last of the LLSingletons -- and ~LLSingletonBase() definitely wants to
+// remove itself from the master list. Since the whole point of this master
+// list is to help track inter-LLSingleton dependencies, and since we have
+// this implicit dependency from every LLSingleton to the master list, make it
+// an LLSingleton.
+class LLSingletonBase::MasterList:
+ public LLSingleton<LLSingletonBase::MasterList>
+{
+private:
+ friend class LLSingleton<LLSingletonBase::MasterList>;
+
+public:
+ // No need to make this private with accessors; nobody outside this source
+ // file can see it.
+ LLSingletonBase::list_t mList;
+};
+
+//static
+LLSingletonBase::list_t& LLSingletonBase::get_master()
+{
+ return LLSingletonBase::MasterList::instance().mList;
+}
+
+void LLSingletonBase::add_master()
+{
+ // As each new LLSingleton is constructed, add to the master list.
+ get_master().push_back(this);
+}
+
+void LLSingletonBase::remove_master()
+{
+ // When an LLSingleton is destroyed, remove from master list.
+ // add_master() used to capture the iterator to the newly-added list item
+ // so we could directly erase() it from the master list. Unfortunately
+ // that runs afoul of destruction-dependency order problems. So search the
+ // master list, and remove this item IF FOUND. We have few enough
+ // LLSingletons, and they are so rarely destroyed (once per run), that the
+ // cost of a linear search should not be an issue.
+ get_master().remove(this);
+}
+
+// Wrapping our initializing list in a static method ensures that it will be
+// constructed on demand. This list doesn't also need to be in an LLSingleton
+// because (a) it should be empty by program shutdown and (b) none of our
+// destructors reference it.
+//static
+LLSingletonBase::list_t& LLSingletonBase::get_initializing()
+{
+ static list_t sList;
+ return sList;
+}
+
+LLSingletonBase::LLSingletonBase():
+ mCleaned(false),
+ mDeleteSingleton(NULL)
+{
+ // Make this the currently-initializing LLSingleton.
+ push_initializing();
+}
+
+LLSingletonBase::~LLSingletonBase() {}
+
+void LLSingletonBase::push_initializing()
+{
+ get_initializing().push_back(this);
+}
+
+void LLSingletonBase::pop_initializing()
+{
+ list_t& list(get_initializing());
+ if (list.empty())
+ {
+ logerrs("Underflow in stack of currently-initializing LLSingletons at ",
+ demangle(typeid(*this).name()).c_str(), "::getInstance()");
+ }
+ if (list.back() != this)
+ {
+ logerrs("Push/pop mismatch in stack of currently-initializing LLSingletons: ",
+ demangle(typeid(*this).name()).c_str(), "::getInstance() trying to pop ",
+ demangle(typeid(*list.back()).name()).c_str());
+ }
+ // Here we're sure that list.back() == this. Whew, pop it.
+ list.pop_back();
+}
+
+void LLSingletonBase::capture_dependency(EInitState initState)
+{
+ // Did this getInstance() call come from another LLSingleton, or from
+ // vanilla application code? Note that although this is a nontrivial
+ // method, the vast majority of its calls arrive here with initializing
+ // empty().
+ list_t& initializing(get_initializing());
+ if (! initializing.empty())
+ {
+ // getInstance() is being called by some other LLSingleton. But -- is
+ // this a circularity? That is, does 'this' already appear in the
+ // initializing stack?
+ // For what it's worth, normally 'initializing' should contain very
+ // few elements.
+ list_t::const_iterator found =
+ std::find(initializing.begin(), initializing.end(), this);
+ if (found != initializing.end())
+ {
+ // Report the circularity. Requiring the coder to dig through the
+ // logic to diagnose exactly how we got here is less than helpful.
+ std::ostringstream out;
+ for ( ; found != initializing.end(); ++found)
+ {
+ // 'found' is an iterator; *found is an LLSingletonBase*; **found
+ // is the actual LLSingletonBase instance.
+ out << demangle(typeid(**found).name()) << " -> ";
+ }
+ // We promise to capture dependencies from both the constructor
+ // and the initSingleton() method, so an LLSingleton's instance
+ // pointer is on the initializing list during both. Now that we've
+ // detected circularity, though, we must distinguish the two. If
+ // the recursive call is from the constructor, we CAN'T honor it:
+ // otherwise we'd be returning a pointer to a partially-
+ // constructed object! But from initSingleton() is okay: that
+ // method exists specifically to support circularity.
+ // Decide which log helper to call based on initState. They have
+ // identical signatures.
+ ((initState == CONSTRUCTING)? logerrs : logwarns)
+ ("LLSingleton circularity: ", out.str().c_str(),
+ demangle(typeid(*this).name()).c_str(), "");
+ }
+ else
+ {
+ // Here 'this' is NOT already in the 'initializing' stack. Great!
+ // Record the dependency.
+ // initializing.back() is the LLSingletonBase* currently being
+ // initialized. Store 'this' in its mDepends set.
+ initializing.back()->mDepends.insert(this);
+ }
+ }
+}
+
+//static
+LLSingletonBase::vec_t LLSingletonBase::dep_sort()
+{
+ // While it would theoretically be possible to maintain a static
+ // SingletonDeps through the life of the program, dynamically adding and
+ // removing LLSingletons as they are created and destroyed, in practice
+ // it's less messy to construct it on demand. The overhead of doing so
+ // should happen basically twice: once for cleanupAll(), once for
+ // deleteAll().
+ typedef LLDependencies<LLSingletonBase*> SingletonDeps;
+ SingletonDeps sdeps;
+ list_t& master(get_master());
+ BOOST_FOREACH(LLSingletonBase* sp, master)
+ {
+ // Build the SingletonDeps structure by adding, for each
+ // LLSingletonBase* sp in the master list, sp itself. It has no
+ // associated value type in our SingletonDeps, hence the 0. We don't
+ // record the LLSingletons it must follow; rather, we record the ones
+ // it must precede. Copy its mDepends to a KeyList to express that.
+ sdeps.add(sp, 0,
+ SingletonDeps::KeyList(),
+ SingletonDeps::KeyList(sp->mDepends.begin(), sp->mDepends.end()));
+ }
+ vec_t ret;
+ ret.reserve(master.size());
+ // We should be able to effect this with a transform_iterator that
+ // extracts just the first (key) element from each sorted_iterator, then
+ // uses vec_t's range constructor... but frankly this is more
+ // straightforward, as long as we remember the above reserve() call!
+ BOOST_FOREACH(SingletonDeps::sorted_iterator::value_type pair, sdeps.sort())
+ {
+ ret.push_back(pair.first);
+ }
+ // The master list is not itself pushed onto the master list. Add it as
+ // the very last entry -- it is the LLSingleton on which ALL others
+ // depend! -- so our caller will process it.
+ ret.push_back(MasterList::getInstance());
+ return ret;
+}
+
+//static
+void LLSingletonBase::cleanupAll()
+{
+ // It's essential to traverse these in dependency order.
+ BOOST_FOREACH(LLSingletonBase* sp, dep_sort())
+ {
+ // Call cleanupSingleton() only if we haven't already done so for this
+ // instance.
+ if (! sp->mCleaned)
+ {
+ sp->mCleaned = true;
+
+ try
+ {
+ sp->cleanupSingleton();
+ }
+ catch (const std::exception& e)
+ {
+ logwarns("Exception in ", demangle(typeid(*sp).name()).c_str(),
+ "::cleanupSingleton(): ", e.what());
+ }
+ catch (...)
+ {
+ logwarns("Unknown exception in ", demangle(typeid(*sp).name()).c_str(),
+ "::cleanupSingleton()");
+ }
+ }
+ }
+}
+
+//static
+void LLSingletonBase::deleteAll()
+{
+ // It's essential to traverse these in dependency order.
+ BOOST_FOREACH(LLSingletonBase* sp, dep_sort())
+ {
+ // Capture the class name first: in case of exception, don't count on
+ // being able to extract it later.
+ const std::string name = demangle(typeid(*sp).name());
+ try
+ {
+ // Call static method through instance function pointer.
+ if (! sp->mDeleteSingleton)
+ {
+ // This Should Not Happen... but carry on.
+ logwarns(name.c_str(), "::mDeleteSingleton not initialized!");
+ }
+ else
+ {
+ // properly initialized: call it.
+ // From this point on, DO NOT DEREFERENCE sp!
+ sp->mDeleteSingleton();
+ }
+ }
+ catch (const std::exception& e)
+ {
+ logwarns("Exception in ", name.c_str(), "::deleteSingleton(): ", e.what());
+ }
+ catch (...)
+ {
+ logwarns("Unknown exception in ", name.c_str(), "::deleteSingleton()");
+ }
+ }
+}
+
+/*------------------------ Final cleanup management ------------------------*/
+class LLSingletonBase::MasterRefcount
+{
+public:
+ // store a POD int so it will be statically initialized to 0
+ int refcount;
+};
+static LLSingletonBase::MasterRefcount sMasterRefcount;
+
+LLSingletonBase::ref_ptr_t LLSingletonBase::get_master_refcount()
+{
+ // Calling this method constructs a new ref_ptr_t, which implicitly calls
+ // intrusive_ptr_add_ref(MasterRefcount*).
+ return &sMasterRefcount;
+}
+
+void intrusive_ptr_add_ref(LLSingletonBase::MasterRefcount* mrc)
+{
+ // Count outstanding SingletonLifetimeManager instances.
+ ++mrc->refcount;
+}
+
+void intrusive_ptr_release(LLSingletonBase::MasterRefcount* mrc)
+{
+ // Notice when each SingletonLifetimeManager instance is destroyed.
+ if (! --mrc->refcount)
+ {
+ // The last instance was destroyed. Time to kill any remaining
+ // LLSingletons -- but in dependency order.
+ LLSingletonBase::deleteAll();
+ }
+}
+
+/*---------------------------- Logging helpers -----------------------------*/
+//static
+void LLSingletonBase::logerrs(const char* p1, const char* p2, const char* p3, const char* p4)
+{
+ // Check LLError::is_available() because some of LLError's infrastructure
+ // is itself an LLSingleton. If that LLSingleton has not yet been
+ // initialized, trying to log will engage LLSingleton machinery... and
+ // around and around we go.
+ if (LLError::is_available())
+ {
+ LL_ERRS() << p1 << p2 << p3 << p4 << LL_ENDL;
+ }
+ else
+ {
+ // Caller may be a test program, or something else whose stderr is
+ // visible to the user.
+ std::cerr << p1 << p2 << p3 << p4 << std::endl;
+ // The other important side effect of LL_ERRS() is
+ // https://www.youtube.com/watch?v=OMG7paGJqhQ (emphasis on OMG)
+ LLError::crashAndLoop(std::string());
+ }
+}
+
+//static
+void LLSingletonBase::logwarns(const char* p1, const char* p2, const char* p3, const char* p4)
+{
+ // See logerrs() remarks about is_available().
+ if (LLError::is_available())
+ {
+ LL_WARNS() << p1 << p2 << p3 << p4 << LL_ENDL;
+ }
+ else
+ {
+ std::cerr << p1 << p2 << p3 << p4 << std::endl;
+ }
+}
+std::string LLSingletonBase::demangle(const char* mangled)
+{
+ return LLError::Log::demangle(mangled);
+}
diff --git a/indra/llcommon/llsingleton.h b/indra/llcommon/llsingleton.h
index 6e6291a165..6a7f27bed4 100644
--- a/indra/llcommon/llsingleton.h
+++ b/indra/llcommon/llsingleton.h
@@ -25,185 +25,387 @@
#ifndef LLSINGLETON_H
#define LLSINGLETON_H
-#include "llerror.h" // *TODO: eliminate this
-
-#include <typeinfo>
#include <boost/noncopyable.hpp>
+#include <boost/unordered_set.hpp>
+#include <boost/intrusive_ptr.hpp>
+#include <list>
+#include <vector>
+#include <typeinfo>
+
+class LLSingletonBase: private boost::noncopyable
+{
+public:
+ class MasterList;
+ class MasterRefcount;
+ typedef boost::intrusive_ptr<MasterRefcount> ref_ptr_t;
+
+private:
+ // All existing LLSingleton instances are tracked in this master list.
+ typedef std::list<LLSingletonBase*> list_t;
+ static list_t& get_master();
+ // This, on the other hand, is a stack whose top indicates the LLSingleton
+ // currently being initialized.
+ static list_t& get_initializing();
+ // Produce a vector<LLSingletonBase*> of master list, in dependency order.
+ typedef std::vector<LLSingletonBase*> vec_t;
+ static vec_t dep_sort();
+
+ bool mCleaned; // cleanupSingleton() has been called
+ // we directly depend on these other LLSingletons
+ typedef boost::unordered_set<LLSingletonBase*> set_t;
+ set_t mDepends;
+
+protected:
+ typedef enum e_init_state
+ {
+ UNINITIALIZED = 0, // must be default-initialized state
+ CONSTRUCTING,
+ INITIALIZING,
+ INITIALIZED,
+ DELETED
+ } EInitState;
+
+ // Base-class constructor should only be invoked by the DERIVED_TYPE
+ // constructor.
+ LLSingletonBase();
+ virtual ~LLSingletonBase();
+
+ // Every new LLSingleton should be added to/removed from the master list
+ void add_master();
+ void remove_master();
+ // with a little help from our friends.
+ template <class T> friend struct LLSingleton_manage_master;
+
+ // Maintain a stack of the LLSingleton subclass instance currently being
+ // initialized. We use this to notice direct dependencies: we want to know
+ // if A requires B. We deduce a dependency if while initializing A,
+ // control reaches B::getInstance().
+ // We want &A to be at the top of that stack during both A::A() and
+ // A::initSingleton(), since a call to B::getInstance() might occur during
+ // either.
+ // Unfortunately the desired timespan does not correspond neatly with a
+ // single C++ scope, else we'd use RAII to track it. But we do know that
+ // LLSingletonBase's constructor definitely runs just before
+ // LLSingleton's, which runs just before the specific subclass's.
+ void push_initializing();
+ // LLSingleton is, and must remain, the only caller to initSingleton().
+ // That being the case, we control exactly when it happens -- and we can
+ // pop the stack immediately thereafter.
+ void pop_initializing();
+ // If a given call to B::getInstance() happens during either A::A() or
+ // A::initSingleton(), record that A directly depends on B.
+ void capture_dependency(EInitState);
+
+ // delegate LL_ERRS() logging to llsingleton.cpp
+ static void logerrs(const char* p1, const char* p2="",
+ const char* p3="", const char* p4="");
+ // delegate LL_WARNS() logging to llsingleton.cpp
+ static void logwarns(const char* p1, const char* p2="",
+ const char* p3="", const char* p4="");
+ static std::string demangle(const char* mangled);
+
+ // obtain canonical ref_ptr_t
+ static ref_ptr_t get_master_refcount();
+
+ // Default methods in case subclass doesn't declare them.
+ virtual void initSingleton() {}
+ virtual void cleanupSingleton() {}
+
+ // deleteSingleton() isn't -- and shouldn't be -- a virtual method. It's a
+ // class static. However, given only Foo*, deleteAll() does need to be
+ // able to reach Foo::deleteSingleton(). Make LLSingleton (which declares
+ // deleteSingleton()) store a pointer here. Since we know it's a static
+ // class method, a classic-C function pointer will do.
+ void (*mDeleteSingleton)();
-// LLSingleton implements the getInstance() method part of the Singleton
-// pattern. It can't make the derived class constructors protected, though, so
-// you have to do that yourself.
-//
-// There are two ways to use LLSingleton. The first way is to inherit from it
-// while using the typename that you'd like to be static as the template
-// parameter, like so:
-//
-// class Foo: public LLSingleton<Foo>{};
-//
-// Foo& instance = Foo::instance();
-//
-// The second way is to use the singleton class directly, without inheritance:
-//
-// typedef LLSingleton<Foo> FooSingleton;
-//
-// Foo& instance = FooSingleton::instance();
-//
-// In this case, the class being managed as a singleton needs to provide an
-// initSingleton() method since the LLSingleton virtual method won't be
-// available
-//
-// As currently written, it is not thread-safe.
+public:
+ /**
+ * Call this to call the cleanupSingleton() method for every LLSingleton
+ * constructed since the start of the last cleanupAll() call. (Any
+ * LLSingleton constructed DURING a cleanupAll() call won't be cleaned up
+ * until the next cleanupAll() call.) cleanupSingleton() neither deletes
+ * nor destroys its LLSingleton; therefore it's safe to include logic that
+ * might take significant realtime or even throw an exception.
+ *
+ * The most important property of cleanupAll() is that cleanupSingleton()
+ * methods are called in dependency order, leaf classes last. Thus, given
+ * two LLSingleton subclasses A and B, if A's dependency on B is properly
+ * expressed as a B::getInstance() or B::instance() call during either
+ * A::A() or A::initSingleton(), B will be cleaned up after A.
+ *
+ * If a cleanupSingleton() method throws an exception, the exception is
+ * logged, but cleanupAll() attempts to continue calling the rest of the
+ * cleanupSingleton() methods.
+ */
+ static void cleanupAll();
+ /**
+ * Call this to call the deleteSingleton() method for every LLSingleton
+ * constructed since the start of the last deleteAll() call. (Any
+ * LLSingleton constructed DURING a deleteAll() call won't be cleaned up
+ * until the next deleteAll() call.) deleteSingleton() deletes and
+ * destroys its LLSingleton. Any cleanup logic that might take significant
+ * realtime -- or throw an exception -- must not be placed in your
+ * LLSingleton's destructor, but rather in its cleanupSingleton() method.
+ *
+ * The most important property of deleteAll() is that deleteSingleton()
+ * methods are called in dependency order, leaf classes last. Thus, given
+ * two LLSingleton subclasses A and B, if A's dependency on B is properly
+ * expressed as a B::getInstance() or B::instance() call during either
+ * A::A() or A::initSingleton(), B will be cleaned up after A.
+ *
+ * If a deleteSingleton() method throws an exception, the exception is
+ * logged, but deleteAll() attempts to continue calling the rest of the
+ * deleteSingleton() methods.
+ */
+ static void deleteAll();
+};
+
+// support ref_ptr_t
+void intrusive_ptr_add_ref(LLSingletonBase::MasterRefcount*);
+void intrusive_ptr_release(LLSingletonBase::MasterRefcount*);
+
+// Most of the time, we want LLSingleton_manage_master() to forward its
+// methods to LLSingletonBase::add_master() and remove_master().
+template <class T>
+struct LLSingleton_manage_master
+{
+ void add(LLSingletonBase* sb) { sb->add_master(); }
+ void remove(LLSingletonBase* sb) { sb->remove_master(); }
+};
+
+// But for the specific case of LLSingletonBase::MasterList, don't.
+template <>
+struct LLSingleton_manage_master<LLSingletonBase::MasterList>
+{
+ void add(LLSingletonBase*) {}
+ void remove(LLSingletonBase*) {}
+};
+/**
+ * LLSingleton implements the getInstance() method part of the Singleton
+ * pattern. It can't make the derived class constructors protected, though, so
+ * you have to do that yourself.
+ *
+ * Derive your class from LLSingleton, passing your subclass name as
+ * LLSingleton's template parameter, like so:
+ *
+ * class Foo: public LLSingleton<Foo>{};
+ *
+ * Foo& instance = Foo::instance();
+ *
+ * LLSingleton recognizes a couple special methods in your derived class.
+ *
+ * If you override LLSingleton<T>::initSingleton(), your method will be called
+ * immediately after the instance is constructed. This is useful for breaking
+ * circular dependencies: if you find that your LLSingleton subclass
+ * constructor references other LLSingleton subclass instances in a chain
+ * leading back to yours, move the instance reference from your constructor to
+ * your initSingleton() method.
+ *
+ * If you override LLSingleton<T>::cleanupSingleton(), your method will be
+ * called if someone calls LLSingletonBase::cleanupAll(). The significant part
+ * of this promise is that cleanupAll() will call individual
+ * cleanupSingleton() methods in reverse dependency order.
+ *
+ * That is, consider LLSingleton subclasses C, B and A. A depends on B, which
+ * in turn depends on C. These dependencies are expressed as calls to
+ * B::instance() or B::getInstance(), and C::instance() or C::getInstance().
+ * It shouldn't matter whether these calls appear in A::A() or
+ * A::initSingleton(), likewise B::B() or B::initSingleton().
+ *
+ * We promise that if you later call LLSingletonBase::cleanupAll():
+ * 1. A::cleanupSingleton() will be called before
+ * 2. B::cleanupSingleton(), which will be called before
+ * 3. C::cleanupSingleton().
+ * Put differently, if your LLSingleton subclass constructor or
+ * initSingleton() method explicitly depends on some other LLSingleton
+ * subclass, you may continue to rely on that other subclass in your
+ * cleanupSingleton() method.
+ *
+ * We introduce a special cleanupSingleton() method because cleanupSingleton()
+ * operations can involve nontrivial realtime, or might throw an exception. A
+ * destructor should do neither!
+ *
+ * If your cleanupSingleton() method throws an exception, we log that
+ * exception but proceed with the remaining cleanupSingleton() calls.
+ *
+ * Similarly, if at some point you call LLSingletonBase::deleteAll(), all
+ * remaining LLSingleton instances will be destroyed in dependency order. (Or
+ * call MySubclass::deleteSingleton() to specifically destroy the canonical
+ * MySubclass instance.)
+ *
+ * As currently written, LLSingleton is not thread-safe.
+ */
template <typename DERIVED_TYPE>
-class LLSingleton : private boost::noncopyable
+class LLSingleton : public LLSingletonBase
{
-
private:
- typedef enum e_init_state
- {
- UNINITIALIZED,
- CONSTRUCTING,
- INITIALIZING,
- INITIALIZED,
- DELETED
- } EInitState;
-
static DERIVED_TYPE* constructSingleton()
{
return new DERIVED_TYPE();
}
-
- // stores pointer to singleton instance
- struct SingletonLifetimeManager
- {
- SingletonLifetimeManager()
- {
- construct();
- }
-
- static void construct()
- {
- sData.mInitState = CONSTRUCTING;
- sData.mInstance = constructSingleton();
- sData.mInitState = INITIALIZING;
- }
-
- ~SingletonLifetimeManager()
- {
- if (sData.mInitState != DELETED)
- {
- deleteSingleton();
- }
- }
- };
-
+
+ // stores pointer to singleton instance
+ struct SingletonLifetimeManager
+ {
+ SingletonLifetimeManager():
+ mMasterRefcount(LLSingletonBase::get_master_refcount())
+ {
+ construct();
+ }
+
+ static void construct()
+ {
+ sData.mInitState = CONSTRUCTING;
+ sData.mInstance = constructSingleton();
+ sData.mInitState = INITIALIZING;
+ }
+
+ ~SingletonLifetimeManager()
+ {
+ // The dependencies between LLSingletons, and the arbitrary order
+ // of static-object destruction, mean that we DO NOT WANT this
+ // destructor to delete this LLSingleton. This destructor will run
+ // without regard to any other LLSingleton whose cleanup might
+ // depend on its existence. What we really want is to count the
+ // runtime's attempts to cleanup LLSingleton static data -- and on
+ // the very last one, call LLSingletonBase::deleteAll(). That
+ // method will properly honor cross-LLSingleton dependencies. This
+ // is why we store an intrusive_ptr to a MasterRefcount: our
+ // ref_ptr_t member counts SingletonLifetimeManager instances.
+ // Once the runtime destroys the last of these, THEN we can delete
+ // every remaining LLSingleton.
+ }
+
+ LLSingletonBase::ref_ptr_t mMasterRefcount;
+ };
+
+protected:
+ LLSingleton()
+ {
+ // populate base-class function pointer with the static
+ // deleteSingleton() function for this particular specialization
+ mDeleteSingleton = &deleteSingleton;
+
+ // add this new instance to the master list
+ LLSingleton_manage_master<DERIVED_TYPE>().add(this);
+ }
+
public:
- virtual ~LLSingleton()
- {
- sData.mInstance = NULL;
- sData.mInitState = DELETED;
- }
-
- /**
- * @brief Immediately delete the singleton.
- *
- * A subsequent call to LLProxy::getInstance() will construct a new
- * instance of the class.
- *
- * LLSingletons are normally destroyed after main() has exited and the C++
- * runtime is cleaning up statically-constructed objects. Some classes
- * derived from LLSingleton have objects that are part of a runtime system
- * that is terminated before main() exits. Calling the destructor of those
- * objects after the termination of their respective systems can cause
- * crashes and other problems during termination of the project. Using this
- * method to destroy the singleton early can prevent these crashes.
- *
- * An example where this is needed is for a LLSingleton that has an APR
- * object as a member that makes APR calls on destruction. The APR system is
- * shut down explicitly before main() exits. This causes a crash on exit.
- * Using this method before the call to apr_terminate() and NOT calling
- * getInstance() again will prevent the crash.
- */
- static void deleteSingleton()
- {
- delete sData.mInstance;
- sData.mInstance = NULL;
- sData.mInitState = DELETED;
- }
-
-
- static DERIVED_TYPE* getInstance()
- {
- static SingletonLifetimeManager sLifeTimeMgr;
-
- switch (sData.mInitState)
- {
- case UNINITIALIZED:
- // should never be uninitialized at this point
- llassert(false);
- return NULL;
- case CONSTRUCTING:
- LL_ERRS() << "Tried to access singleton " << typeid(DERIVED_TYPE).name() << " from singleton constructor!" << LL_ENDL;
- return NULL;
- case INITIALIZING:
- // go ahead and flag ourselves as initialized so we can be reentrant during initialization
- sData.mInitState = INITIALIZED;
- // initialize singleton after constructing it so that it can reference other singletons which in turn depend on it,
- // thus breaking cyclic dependencies
- sData.mInstance->initSingleton();
- return sData.mInstance;
- case INITIALIZED:
- return sData.mInstance;
- case DELETED:
- LL_WARNS() << "Trying to access deleted singleton " << typeid(DERIVED_TYPE).name() << " creating new instance" << LL_ENDL;
- SingletonLifetimeManager::construct();
- // same as first time construction
- sData.mInitState = INITIALIZED;
- sData.mInstance->initSingleton();
- return sData.mInstance;
- }
-
- return NULL;
- }
-
- static DERIVED_TYPE* getIfExists()
- {
- return sData.mInstance;
- }
-
- // Reference version of getInstance()
- // Preferred over getInstance() as it disallows checking for NULL
- static DERIVED_TYPE& instance()
- {
- return *getInstance();
- }
-
- // Has this singleton been created uet?
- // Use this to avoid accessing singletons before the can safely be constructed
- static bool instanceExists()
- {
- return sData.mInitState == INITIALIZED;
- }
-
- // Has this singleton already been deleted?
- // Use this to avoid accessing singletons from a static object's destructor
- static bool destroyed()
- {
- return sData.mInitState == DELETED;
- }
+ virtual ~LLSingleton()
+ {
+ // remove this instance from the master list
+ LLSingleton_manage_master<DERIVED_TYPE>().remove(this);
+ sData.mInstance = NULL;
+ sData.mInitState = DELETED;
+ }
-private:
+ /**
+ * @brief Immediately delete the singleton.
+ *
+ * A subsequent call to LLProxy::getInstance() will construct a new
+ * instance of the class.
+ *
+ * Without an explicit call to LLSingletonBase::deleteAll(), LLSingletons
+ * are implicitly destroyed after main() has exited and the C++ runtime is
+ * cleaning up statically-constructed objects. Some classes derived from
+ * LLSingleton have objects that are part of a runtime system that is
+ * terminated before main() exits. Calling the destructor of those objects
+ * after the termination of their respective systems can cause crashes and
+ * other problems during termination of the project. Using this method to
+ * destroy the singleton early can prevent these crashes.
+ *
+ * An example where this is needed is for a LLSingleton that has an APR
+ * object as a member that makes APR calls on destruction. The APR system is
+ * shut down explicitly before main() exits. This causes a crash on exit.
+ * Using this method before the call to apr_terminate() and NOT calling
+ * getInstance() again will prevent the crash.
+ */
+ static void deleteSingleton()
+ {
+ delete sData.mInstance;
+ sData.mInstance = NULL;
+ sData.mInitState = DELETED;
+ }
+
+ static DERIVED_TYPE* getInstance()
+ {
+ static SingletonLifetimeManager sLifeTimeMgr;
+
+ switch (sData.mInitState)
+ {
+ case UNINITIALIZED:
+ // should never be uninitialized at this point
+ logerrs("Uninitialized singleton ",
+ demangle(typeid(DERIVED_TYPE).name()).c_str());
+ return NULL;
+
+ case CONSTRUCTING:
+ logerrs("Tried to access singleton ",
+ demangle(typeid(DERIVED_TYPE).name()).c_str(),
+ " from singleton constructor!");
+ return NULL;
- virtual void initSingleton() {}
+ case INITIALIZING:
+ // go ahead and flag ourselves as initialized so we can be
+ // reentrant during initialization
+ sData.mInitState = INITIALIZED;
+ // initialize singleton after constructing it so that it can
+ // reference other singletons which in turn depend on it, thus
+ // breaking cyclic dependencies
+ sData.mInstance->initSingleton();
+ // pop this off stack of initializing singletons
+ sData.mInstance->pop_initializing();
+ break;
+
+ case INITIALIZED:
+ break;
+
+ case DELETED:
+ logwarns("Trying to access deleted singleton ",
+ demangle(typeid(DERIVED_TYPE).name()).c_str(),
+ " -- creating new instance");
+ SingletonLifetimeManager::construct();
+ // same as first time construction
+ sData.mInitState = INITIALIZED;
+ sData.mInstance->initSingleton();
+ // pop this off stack of initializing singletons
+ sData.mInstance->pop_initializing();
+ break;
+ }
+
+ // By this point, if DERIVED_TYPE was pushed onto the initializing
+ // stack, it has been popped off. So the top of that stack, if any, is
+ // an LLSingleton that directly depends on DERIVED_TYPE. If this call
+ // came from another LLSingleton, rather than from vanilla application
+ // code, record the dependency.
+ sData.mInstance->capture_dependency(sData.mInitState);
+ return sData.mInstance;
+ }
- struct SingletonData
- {
- // explicitly has a default constructor so that member variables are zero initialized in BSS
- // and only changed by singleton logic, not constructor running during startup
- EInitState mInitState;
- DERIVED_TYPE* mInstance;
- };
- static SingletonData sData;
+ // Reference version of getInstance()
+ // Preferred over getInstance() as it disallows checking for NULL
+ static DERIVED_TYPE& instance()
+ {
+ return *getInstance();
+ }
+
+ // Has this singleton been created yet?
+ // Use this to avoid accessing singletons before they can safely be constructed.
+ static bool instanceExists()
+ {
+ return sData.mInitState == INITIALIZED;
+ }
+
+private:
+ struct SingletonData
+ {
+ // explicitly has a default constructor so that member variables are zero initialized in BSS
+ // and only changed by singleton logic, not constructor running during startup
+ EInitState mInitState;
+ DERIVED_TYPE* mInstance;
+ };
+ static SingletonData sData;
};
template<typename T>
diff --git a/indra/llcommon/tests/llpounceable_test.cpp b/indra/llcommon/tests/llpounceable_test.cpp
new file mode 100644
index 0000000000..2f4915ce11
--- /dev/null
+++ b/indra/llcommon/tests/llpounceable_test.cpp
@@ -0,0 +1,230 @@
+/**
+ * @file llpounceable_test.cpp
+ * @author Nat Goodspeed
+ * @date 2015-05-22
+ * @brief Test for llpounceable.
+ *
+ * $LicenseInfo:firstyear=2015&license=viewerlgpl$
+ * Copyright (c) 2015, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "llpounceable.h"
+// STL headers
+// std headers
+// external library headers
+#include <boost/bind.hpp>
+// other Linden headers
+#include "../test/lltut.h"
+
+/*----------------------------- string testing -----------------------------*/
+void append(std::string* dest, const std::string& src)
+{
+ dest->append(src);
+}
+
+/*-------------------------- Data-struct testing ---------------------------*/
+struct Data
+{
+ Data(const std::string& data):
+ mData(data)
+ {}
+ const std::string mData;
+};
+
+void setter(Data** dest, Data* ptr)
+{
+ *dest = ptr;
+}
+
+static Data* static_check = 0;
+
+// Set up an extern pointer to an LLPounceableStatic so the linker will fill
+// in the forward reference from below, before runtime.
+extern LLPounceable<Data*, LLPounceableStatic> gForward;
+
+struct EnqueueCall
+{
+ EnqueueCall()
+ {
+ // Intentionally use a forward reference to an LLPounceableStatic that
+ // we believe is NOT YET CONSTRUCTED. This models the scenario in
+ // which a constructor in another translation unit runs before
+ // constructors in this one. We very specifically want callWhenReady()
+ // to work even in that case: we need the LLPounceableQueueImpl to be
+ // initialized even if the LLPounceable itself is not.
+ gForward.callWhenReady(boost::bind(setter, &static_check, _1));
+ }
+} nqcall;
+// When this declaration is processed, we should enqueue the
+// setter(&static_check, _1) call for when gForward is set non-NULL. Needless
+// to remark, we want this call not to crash.
+
+// Now declare gForward. Its constructor should not run until after nqcall's.
+LLPounceable<Data*, LLPounceableStatic> gForward;
+
+/*****************************************************************************
+* TUT
+*****************************************************************************/
+namespace tut
+{
+ struct llpounceable_data
+ {
+ };
+ typedef test_group<llpounceable_data> llpounceable_group;
+ typedef llpounceable_group::object object;
+ llpounceable_group llpounceablegrp("llpounceable");
+
+ template<> template<>
+ void object::test<1>()
+ {
+ set_test_name("LLPounceableStatic out-of-order test");
+ // LLPounceable<T, LLPounceableStatic>::callWhenReady() must work even
+ // before LLPounceable's constructor runs. That's the whole point of
+ // implementing it with an LLSingleton queue. This models (say)
+ // LLPounceableStatic<LLMessageSystem*, LLPounceableStatic>.
+ ensure("static_check should still be null", ! static_check);
+ Data myData("test<1>");
+ gForward = &myData; // should run setter
+ ensure_equals("static_check should be &myData", static_check, &myData);
+ }
+
+ template<> template<>
+ void object::test<2>()
+ {
+ set_test_name("LLPounceableQueue different queues");
+ // We expect that LLPounceable<T, LLPounceableQueue> should have
+ // different queues because that specialization stores the queue
+ // directly in the LLPounceable instance.
+ Data *aptr = 0, *bptr = 0;
+ LLPounceable<Data*> a, b;
+ a.callWhenReady(boost::bind(setter, &aptr, _1));
+ b.callWhenReady(boost::bind(setter, &bptr, _1));
+ ensure("aptr should be null", ! aptr);
+ ensure("bptr should be null", ! bptr);
+ Data adata("a"), bdata("b");
+ a = &adata;
+ ensure_equals("aptr should be &adata", aptr, &adata);
+ // but we haven't yet set b
+ ensure("bptr should still be null", !bptr);
+ b = &bdata;
+ ensure_equals("bptr should be &bdata", bptr, &bdata);
+ }
+
+ template<> template<>
+ void object::test<3>()
+ {
+ set_test_name("LLPounceableStatic different queues");
+ // LLPounceable<T, LLPounceableStatic> should also have a distinct
+ // queue for each instance, but that engages an additional map lookup
+ // because there's only one LLSingleton for each T.
+ Data *aptr = 0, *bptr = 0;
+ LLPounceable<Data*, LLPounceableStatic> a, b;
+ a.callWhenReady(boost::bind(setter, &aptr, _1));
+ b.callWhenReady(boost::bind(setter, &bptr, _1));
+ ensure("aptr should be null", ! aptr);
+ ensure("bptr should be null", ! bptr);
+ Data adata("a"), bdata("b");
+ a = &adata;
+ ensure_equals("aptr should be &adata", aptr, &adata);
+ // but we haven't yet set b
+ ensure("bptr should still be null", !bptr);
+ b = &bdata;
+ ensure_equals("bptr should be &bdata", bptr, &bdata);
+ }
+
+ template<> template<>
+ void object::test<4>()
+ {
+ set_test_name("LLPounceable<T> looks like T");
+ // We want LLPounceable<T, TAG> to be drop-in replaceable for a plain
+ // T for read constructs. In particular, it should behave like a dumb
+ // pointer -- and with zero abstraction cost for such usage.
+ Data* aptr = 0;
+ Data a("a");
+ // should be able to initialize a pounceable (when its constructor
+ // runs)
+ LLPounceable<Data*> pounceable(&a);
+ // should be able to pass LLPounceable<T> to function accepting T
+ setter(&aptr, pounceable);
+ ensure_equals("aptr should be &a", aptr, &a);
+ // should be able to dereference with *
+ ensure_equals("deref with *", (*pounceable).mData, "a");
+ // should be able to dereference with ->
+ ensure_equals("deref with ->", pounceable->mData, "a");
+ // bool operations
+ ensure("test with operator bool()", pounceable);
+ ensure("test with operator !()", ! (! pounceable));
+ }
+
+ template<> template<>
+ void object::test<5>()
+ {
+ set_test_name("Multiple callWhenReady() queue items");
+ Data *p1 = 0, *p2 = 0, *p3 = 0;
+ Data a("a");
+ LLPounceable<Data*> pounceable;
+ // queue up a couple setter() calls for later
+ pounceable.callWhenReady(boost::bind(setter, &p1, _1));
+ pounceable.callWhenReady(boost::bind(setter, &p2, _1));
+ // should still be pending
+ ensure("p1 should be null", !p1);
+ ensure("p2 should be null", !p2);
+ ensure("p3 should be null", !p3);
+ pounceable = 0;
+ // assigning a new empty value shouldn't flush the queue
+ ensure("p1 should still be null", !p1);
+ ensure("p2 should still be null", !p2);
+ ensure("p3 should still be null", !p3);
+ // using whichever syntax
+ pounceable.reset(0);
+ // try to make ensure messages distinct... tough to pin down which
+ // ensure() failed if multiple ensure() calls in the same test<n> have
+ // the same message!
+ ensure("p1 should again be null", !p1);
+ ensure("p2 should again be null", !p2);
+ ensure("p3 should again be null", !p3);
+ pounceable.reset(&a); // should flush queue
+ ensure_equals("p1 should be &a", p1, &a);
+ ensure_equals("p2 should be &a", p2, &a);
+ ensure("p3 still not set", !p3);
+ // immediate call
+ pounceable.callWhenReady(boost::bind(setter, &p3, _1));
+ ensure_equals("p3 should be &a", p3, &a);
+ }
+
+ template<> template<>
+ void object::test<6>()
+ {
+ set_test_name("queue order");
+ std::string data;
+ LLPounceable<std::string*> pounceable;
+ pounceable.callWhenReady(boost::bind(append, _1, "a"));
+ pounceable.callWhenReady(boost::bind(append, _1, "b"));
+ pounceable.callWhenReady(boost::bind(append, _1, "c"));
+ pounceable = &data;
+ ensure_equals("callWhenReady() must preserve chronological order",
+ data, "abc");
+
+ std::string data2;
+ pounceable = NULL;
+ pounceable.callWhenReady(boost::bind(append, _1, "d"));
+ pounceable.callWhenReady(boost::bind(append, _1, "e"));
+ pounceable.callWhenReady(boost::bind(append, _1, "f"));
+ pounceable = &data2;
+ ensure_equals("LLPounceable must reset queue when fired",
+ data2, "def");
+ }
+
+ template<> template<>
+ void object::test<7>()
+ {
+ set_test_name("compile-fail test, uncomment to check");
+ // The following declaration should fail: only LLPounceableQueue and
+ // LLPounceableStatic should work as tags.
+// LLPounceable<Data*, int> pounceable;
+ }
+} // namespace tut
diff --git a/indra/llcommon/tests/llsingleton_test.cpp b/indra/llcommon/tests/llsingleton_test.cpp
index 385289aefe..a05f650f25 100644
--- a/indra/llcommon/tests/llsingleton_test.cpp
+++ b/indra/llcommon/tests/llsingleton_test.cpp
@@ -30,47 +30,171 @@
#include "llsingleton.h"
#include "../test/lltut.h"
+
+// Capture execution sequence by appending to log string.
+std::string sLog;
+
+#define DECLARE_CLASS(CLS) \
+struct CLS: public LLSingleton<CLS> \
+{ \
+ static enum dep_flag { \
+ DEP_NONE, /* no dependency */ \
+ DEP_CTOR, /* dependency in ctor */ \
+ DEP_INIT /* dependency in initSingleton */ \
+ } sDepFlag; \
+ \
+ CLS(); \
+ void initSingleton(); \
+ void cleanupSingleton(); \
+ ~CLS(); \
+}; \
+ \
+CLS::dep_flag CLS::sDepFlag = DEP_NONE
+
+DECLARE_CLASS(A);
+DECLARE_CLASS(B);
+
+#define DEFINE_MEMBERS(CLS, OTHER) \
+CLS::CLS() \
+{ \
+ sLog.append(#CLS); \
+ if (sDepFlag == DEP_CTOR) \
+ { \
+ (void)OTHER::instance(); \
+ } \
+} \
+ \
+void CLS::initSingleton() \
+{ \
+ sLog.append("i" #CLS); \
+ if (sDepFlag == DEP_INIT) \
+ { \
+ (void)OTHER::instance(); \
+ } \
+} \
+ \
+void CLS::cleanupSingleton() \
+{ \
+ sLog.append("x" #CLS); \
+} \
+ \
+CLS::~CLS() \
+{ \
+ sLog.append("~" #CLS); \
+}
+
+DEFINE_MEMBERS(A, B)
+DEFINE_MEMBERS(B, A)
+
namespace tut
{
- struct singleton
- {
- // We need a class created with the LLSingleton template to test with.
- class LLSingletonTest: public LLSingleton<LLSingletonTest>
- {
-
- };
- };
-
- typedef test_group<singleton> singleton_t;
- typedef singleton_t::object singleton_object_t;
- tut::singleton_t tut_singleton("LLSingleton");
-
- template<> template<>
- void singleton_object_t::test<1>()
- {
-
- }
- template<> template<>
- void singleton_object_t::test<2>()
- {
- LLSingletonTest* singleton_test = LLSingletonTest::getInstance();
- ensure(singleton_test);
- }
- template<> template<>
- void singleton_object_t::test<3>()
- {
- //Construct the instance
- LLSingletonTest::getInstance();
- ensure(LLSingletonTest::instanceExists());
-
- //Delete the instance
- LLSingletonTest::deleteSingleton();
- ensure(LLSingletonTest::destroyed());
- ensure(!LLSingletonTest::instanceExists());
-
- //Construct it again.
- LLSingletonTest* singleton_test = LLSingletonTest::getInstance();
- ensure(singleton_test);
- ensure(LLSingletonTest::instanceExists());
- }
+ struct singleton
+ {
+ // We need a class created with the LLSingleton template to test with.
+ class LLSingletonTest: public LLSingleton<LLSingletonTest>
+ {
+
+ };
+ };
+
+ typedef test_group<singleton> singleton_t;
+ typedef singleton_t::object singleton_object_t;
+ tut::singleton_t tut_singleton("LLSingleton");
+
+ template<> template<>
+ void singleton_object_t::test<1>()
+ {
+
+ }
+ template<> template<>
+ void singleton_object_t::test<2>()
+ {
+ LLSingletonTest* singleton_test = LLSingletonTest::getInstance();
+ ensure(singleton_test);
+ }
+
+ template<> template<>
+ void singleton_object_t::test<3>()
+ {
+ //Construct the instance
+ LLSingletonTest::getInstance();
+ ensure(LLSingletonTest::instanceExists());
+
+ //Delete the instance
+ LLSingletonTest::deleteSingleton();
+ ensure(!LLSingletonTest::instanceExists());
+
+ //Construct it again.
+ LLSingletonTest* singleton_test = LLSingletonTest::getInstance();
+ ensure(singleton_test);
+ ensure(LLSingletonTest::instanceExists());
+ }
+
+#define TESTS(CLS, OTHER, N0, N1, N2, N3) \
+ template<> template<> \
+ void singleton_object_t::test<N0>() \
+ { \
+ set_test_name("just " #CLS); \
+ CLS::sDepFlag = CLS::DEP_NONE; \
+ OTHER::sDepFlag = OTHER::DEP_NONE; \
+ sLog.clear(); \
+ \
+ (void)CLS::instance(); \
+ ensure_equals(sLog, #CLS "i" #CLS); \
+ LLSingletonBase::cleanupAll(); \
+ ensure_equals(sLog, #CLS "i" #CLS "x" #CLS); \
+ LLSingletonBase::deleteAll(); \
+ ensure_equals(sLog, #CLS "i" #CLS "x" #CLS "~" #CLS); \
+ } \
+ \
+ template<> template<> \
+ void singleton_object_t::test<N1>() \
+ { \
+ set_test_name(#CLS " ctor depends " #OTHER); \
+ CLS::sDepFlag = CLS::DEP_CTOR; \
+ OTHER::sDepFlag = OTHER::DEP_NONE; \
+ sLog.clear(); \
+ \
+ (void)CLS::instance(); \
+ ensure_equals(sLog, #CLS #OTHER "i" #OTHER "i" #CLS); \
+ LLSingletonBase::cleanupAll(); \
+ ensure_equals(sLog, #CLS #OTHER "i" #OTHER "i" #CLS "x" #CLS "x" #OTHER); \
+ LLSingletonBase::deleteAll(); \
+ ensure_equals(sLog, #CLS #OTHER "i" #OTHER "i" #CLS "x" #CLS "x" #OTHER "~" #CLS "~" #OTHER); \
+ } \
+ \
+ template<> template<> \
+ void singleton_object_t::test<N2>() \
+ { \
+ set_test_name(#CLS " init depends " #OTHER); \
+ CLS::sDepFlag = CLS::DEP_INIT; \
+ OTHER::sDepFlag = OTHER::DEP_NONE; \
+ sLog.clear(); \
+ \
+ (void)CLS::instance(); \
+ ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER); \
+ LLSingletonBase::cleanupAll(); \
+ ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER "x" #CLS "x" #OTHER); \
+ LLSingletonBase::deleteAll(); \
+ ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER "x" #CLS "x" #OTHER "~" #CLS "~" #OTHER); \
+ } \
+ \
+ template<> template<> \
+ void singleton_object_t::test<N3>() \
+ { \
+ set_test_name(#CLS " circular init"); \
+ CLS::sDepFlag = CLS::DEP_INIT; \
+ OTHER::sDepFlag = OTHER::DEP_CTOR; \
+ sLog.clear(); \
+ \
+ (void)CLS::instance(); \
+ ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER); \
+ LLSingletonBase::cleanupAll(); \
+ ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER "x" #CLS "x" #OTHER); \
+ LLSingletonBase::deleteAll(); \
+ ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER "x" #CLS "x" #OTHER "~" #CLS "~" #OTHER); \
+ }
+
+ TESTS(A, B, 4, 5, 6, 7)
+ TESTS(B, A, 8, 9, 10, 11)
}
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