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2024-04-17Reintroduce LLCoros::killreq() to request killing a named coroutine.Nat Goodspeed
Make LLCoros constructor echo "LLApp" status-change events on new "LLCoros" event pump. Rename LLCoros::kill() to killreq() because this operation only registers a request for the named coroutine to terminate next time it calls checkStop(). Add a new CoroData member to record the name of the coroutine requesting termination. killreq() sets that and also posts "killreq" to "LLCoros". Add an optional final-cleanup callback to LLCoros::checkStop(). Make checkStop() check for a pending killreq() request as well as viewer termination. Introduce new LLCoros::Killed exception for that case. Introduce LLCoros::getStopListener(), with two overloads, to encapsulate some of the messy logic to listen (perhaps temporarily) for viewer shutdown. Both overloads are for use by code at the source end of a queue or promise or other resource for which coroutines might still be waiting at viewer shutdown time. One overload is specifically for when the caller knows the name of the one and only coroutine that will wait on the resource (e.g. because the caller IS that coroutine). That overload honors killreq(). Use getStopListener() to simplify the four existing places where we set up such a listener. Add a fifth: also make WorkQueue listen for viewer shutdown (resolving a TODO comment). Remove LLLUAmanager::terminateScript(), getTerminationList() and the static sTerminationList. In the Lua interrupt callback, instead of checking sTerminationList, call LLCoros::checkStop(). Change LLFloaterLUAScripts terminate-script logic to call LLCoros::killreq() instead of posting on "LLLua" and calling LLLUAmanager::terminateScript(). Drop LLApp::setStatus() posting to "LLLua" LLEventPump: the above makes that moot.
2023-02-14DRTVWR-489-emoji: As part of the work to get macOS version of the Viewer ↵Callum Prentice
working, the flag was introduced to warn (and therefore error out) when a virtual override was not marked with the 'override' keyword. Fixing this up involved a large number of changes and this commit represents just those changes - nothing specially from the DRTVWR-489 viewer (Cherry pick of 3 commits from Callum to declutter the emoji PR: 3185bdea27b19e155c2ccc03c80624e113d312a6, 923733e591eb547ad5dfec395ce7d3e8f0468c16 and 6f31fabbc2d082b77c8f09bce30234ec9c506e33)
2022-10-13Revert "Restored SL-14961"Andrey Kleshchev
This partially reverts commit 935c1362a222f192bf913270d01f6c31c16e175b. Reporting seems to have stoped working, trying the same way mac works.
2022-02-14Restored SL-14961Andrey Kleshchev
SL-14961 works better for windows than rethrow
2022-02-11SL-10190: Slightly reduce conditional clutter in llcoros.{h,cpp}.Nat Goodspeed
Rename 'winlevel()' to 'sehandle()'; change it from a static member function to a free function, thus eliminating the conditional in llcoros.h. Elsewhere than Windows, provide a zero-cost pass-through sehandle() implementation, eliminating the conditional in toplevel(). # Conflicts: # indra/llcommon/llcoros.cpp # indra/llcommon/llcoros.h
2022-02-11SL-10190: Introduce LLCoros::saveException() and rethrow().Nat Goodspeed
This mechanism uses a queue of std::exception_ptrs to transport an (otherwise) uncaught exception from a terminated coroutine to the thread's main fiber. The main loop calls LLCoros::rethrow() just after giving some cycles to ready coroutines that frame. # Conflicts: # indra/llcommon/llcoros.cpp # indra/llcommon/llcoros.h # indra/newview/llappviewer.cpp
2022-02-11Revert "SL-14961 Coroutine crash was not reported to bugsplat"Andrey Kleshchev
Will be replaced with retrow from nat
2021-07-20Merge branch 'master' into DRTVWR-521-maintAndrey Lihatskiy
# Conflicts: # autobuild.xml # indra/llcommon/llerror.cpp # indra/llui/llnotifications.h # indra/newview/llappviewer.cpp # indra/newview/llappviewermacosx.cpp
2021-07-19SL-15292 Voice's singleton shutdown before voice's coroutineAndrey Kleshchev
2021-03-13SL-14961 Coroutine crash was not reported to bugsplatAndrey Kleshchev
2020-07-07DRTVWR-476, SL-13555: Don't crash if user closes viewer during login.Nat Goodspeed
Ever since February 2010, the body of the login coroutine function has been enclosed in try/catch (...), with an llerrs message to try to crash more informatively than the runtime's unhandled-exception termination. Over the years this evolved to LL_ERRS and then to CRASH_ON_UNHANDLED_EXCEPTION. This persisted despite the August 2016 addition of generic catch clauses in the LLCoros::toplevel() function to serve the same purpose, and despite the subsequent introduction of the LLCoros::Stop family of exceptions to deliberately throw into waiting coroutines on viewer shutdown. That's exactly what was happening. When the user closed the viewer while waiting for the response from login.cgi, the waiting operation threw LLCoros::Stopping, which was caught by that CRASH_ON_UNHANDLED_EXCEPTION, which crashed the viewer with LL_ERRS rather than propagating up to the toplevel() and cleanly terminating the coroutine. Change CRASH_ON_UNHANDLED_EXCEPTION() to LOG_UNHANDLED_EXCEPTION() and re-throw so toplevel() can handle.
2020-05-14DRTVWR-476: Wrap boost::fibers::mutex et al. with LLCoros aliases.Nat Goodspeed
Specifically: LLCoros::Mutex means boost::fibers::mutex LLCoros::LockType means std::unique_lock<boost::fibers::mutex> LLCoros::ConditionVariable means boost::fibers::condition_variable LLCoros::cv_status means boost::fibers::cv_status So as not to drag in all of boost::fibers::mutex.hpp or condition_variable.hpp for each consumer of llcoros.h, instead #define LLCOROS_MUTEX_HEADER and LLCOROS_CONDVAR_HEADER. Those who need them can #include the relevant macro. Update llcond.h and llthreadsafequeue.h accordingly.
2020-03-25DRTVWR-476: Make llcoro::logname() distinguish different threads.Nat Goodspeed
Actually, introduce static LLCoros::logname() and make the namespaced free function an alias for that. Because CoroData is a subclass of LLInstanceTracker with a key, every instance requires a distinct key. That conflicts with our "getName() returns empty string for default coroutine on thread" convention. Introduce a new CoroData constructor, specifically for the default coroutine on each thread, that initializes the getName() name to empty string while providing a distinct "mainN" key. Make get_CoroData() use that new constructor for its thread_local instance, passing an atomic<int> incremented each time we initialize one for a new thread. Then LLCoros::logname() returns either the getName() name or the key.
2020-03-25DRTVWR-476, SL-12197: Don't throw Stopping from main coroutine.Nat Goodspeed
The new LLCoros::Stop exception is intended to terminate long-lived coroutines -- not interrupt mainstream shutdown processing. Only throw it on an explicitly-launched coroutine. Make LLCoros::getName() (used by the above test) static. As with other LLCoros methods, it might be called after the LLCoros LLSingleton instance has been deleted. Requiring the caller to call instance() implies a possible need to also call wasDeleted(). Encapsulate that nuance into a static method instead.
2020-03-25DRTVWR-476: Keep coroutine-local data on toplevel()'s stack frame.Nat Goodspeed
Instead of heap-allocating a CoroData instance per coroutine, storing the pointer in a ptr_map and deleting it from the ptr_map once the fiber_specific_ptr for that coroutine is cleaned up -- just declare a stack instance on the top-level stack frame, the simplest C++ lifespan management. Derive CoroData from LLInstanceTracker to detect potential name collisions and to enumerate instances. Continue registering each coroutine's CoroData instance in our fiber_specific_ptr, but use a no-op deleter function. Make ~LLCoros() directly pump the fiber scheduler a few times, instead of having a special "LLApp" listener.
2020-03-25DRTVWR-476: Back out changeset 40c0c6a8407d ("final" LLApp listener)Nat Goodspeed
2020-03-25DRTVWR-476: Pump coroutines a few more times when we start quitting.Nat Goodspeed
By the time "LLApp" listeners are notified that the app is quitting, the mainloop is no longer running. Even though those listeners do things like close work queues and inject exceptions into pending promises, any coroutines waiting on those resources must regain control before they can notice and shut down properly. Add a final "LLApp" listener that resumes ready coroutines a few more times. Make sure every other "LLApp" listener is positioned before that new one.
2020-03-25DRTVWR-476: Infrastructure to help manage long-lived coroutines.Nat Goodspeed
Introduce LLCoros::Stop exception, with subclasses Stopping, Stopped and Shutdown. Add LLCoros::checkStop(), intended to be called periodically by any coroutine with nontrivial lifespan. It checks the LLApp status and, unless isRunning(), throws one of these new exceptions. Make LLCoros::toplevel() catch Stop specially and log forcible coroutine termination. Now that LLApp status matters even in a test program, introduce a trivial LLTestApp subclass whose sole function is to make isRunning() true. (LLApp::setStatus() is protected: only a subclass can call it.) Add LLTestApp instances to lleventcoro_test.cpp and lllogin_test.cpp. Make LLCoros::toplevel() accept parameters by value rather than by const reference so we can continue using them even after context switches. Make private LLCoros::get_CoroData() static. Given that we've observed some coroutines living past LLCoros destruction, making the caller call LLCoros::instance() is more dangerous than encapsulating it within a static method -- since the encapsulated call can check LLCoros::wasDeleted() first and do something reasonable instead. This also eliminates the need for both a const and non-const overload. Defend LLCoros::delete_CoroData() (cleanup function for fiber_specific_ptr for CoroData, implicitly called after coroutine termination) against calls after ~LLCoros(). Add a status string to coroutine-local data, with LLCoro::setStatus(), getStatus() and RAII class TempStatus. Add an optional 'when' string argument to LLCoros::printActiveCoroutines(). Make ~LLCoros() print the coroutines still active at destruction.
2020-03-25DRTVWR-476: Add Sync class to help with stepwise coroutine tests.Nat Goodspeed
Sync is specifically intended for test programs. It is based on an LLScalarCond<int>. The idea is that each of two coroutines can watch for the other to get a chance to run, indicated by incrementing the wrapped int and notifying the wrapped condition_variable. This is less hand-wavy than calling llcoro::suspend() and hoping that the other routine will have had a chance to run. Use Sync in lleventcoro_test.cpp. Also refactor lleventcoro_test.cpp so that instead of a collection of static data requiring a clear() call at start of each individual test function, the relevant data is all part of the test_data struct common to all test functions. Make the helper coroutine functions members of test_data too. Introduce llcoro::logname(), a convenience function to log the name of the currently executing coroutine or "main" if in the thread's main coroutine.
2020-03-25SL-793: Use Boost.Fiber instead of the "dcoroutine" library.Nat Goodspeed
Longtime fans will remember that the "dcoroutine" library is a Google Summer of Code project by Giovanni P. Deretta. He originally called it "Boost.Coroutine," and we originally added it to our 3p-boost autobuild package as such. But when the official Boost.Coroutine library came along (with a very different API), and we still needed the API of the GSoC project, we renamed the unofficial one "dcoroutine" to allow coexistence. The "dcoroutine" library had an internal low-level API more or less analogous to Boost.Context. We later introduced an implementation of that internal API based on Boost.Context, a step towards eliminating the GSoC code in favor of official, supported Boost code. However, recent versions of Boost.Context no longer support the API on which we built the shim for "dcoroutine." We started down the path of reimplementing that shim using the current Boost.Context API -- then realized that it's time to bite the bullet and replace the "dcoroutine" API with the Boost.Fiber API, which we've been itching to do for literally years now. Naturally, most of the heavy lifting is in llcoros.{h,cpp} and lleventcoro.{h,cpp} -- which is good: the LLCoros layer abstracts away most of the differences between "dcoroutine" and Boost.Fiber. The one feature Boost.Fiber does not provide is the ability to forcibly terminate some other fiber. Accordingly, disable LLCoros::kill() and LLCoprocedureManager::shutdown(). The only known shutdown() call was in LLCoprocedurePool's destructor. We also took the opportunity to remove postAndSuspend2() and its associated machinery: FutureListener2, LLErrorEvent, errorException(), errorLog(), LLCoroEventPumps. All that dual-LLEventPump stuff was introduced at a time when the Responder pattern was king, and we assumed we'd want to listen on one LLEventPump with the success handler and on another with the error handler. We have never actually used that in practice. Remove associated tests, of course. There is one other semantic difference that necessitates patching a number of tests: with "dcoroutine," fulfilling a future IMMEDIATELY resumes the waiting coroutine. With Boost.Fiber, fulfilling a future merely marks the fiber as ready to resume next time the scheduler gets around to it. To observe the test side effects, we've inserted a number of llcoro::suspend() calls -- also in the main loop. For a long time we retained a single unit test exercising the raw "dcoroutine" API. Remove that. Eliminate llcoro_get_id.{h,cpp}, which provided llcoro::get_id(), which was a hack to emulate fiber-local variables. Since Boost.Fiber has an actual API for that, remove the hack. In fact, use (new alias) LLCoros::local_ptr for LLSingleton's dependency tracking in place of llcoro::get_id(). In CMake land, replace BOOST_COROUTINE_LIBRARY with BOOST_FIBER_LIBRARY. We don't actually use the Boost.Coroutine for anything (though there exist plausible use cases).
2018-10-04DRTVWR-474: Make login coroutine sync with updater process on failure.Nat Goodspeed
Specifically, introduce an LLEventMailDrop("LoginSync"). When the updater detects that an update is required, it will post to that rendezvous point. When login.cgi responds with login failure, make the login coroutine wait (a few seconds) for that ping from the updater. If we receive that ping and if it contains a "reply" key, make the fail.login listener respond to the updater with an indication of whether to proceed with update. If both login.cgi and the updater concur that an update is required, produce a new confirmation message for the user and then (once user responds) tell the updater to proceed. Otherwise, produce the usual login-failure message and tell the updater never mind. Introduce LLCoro::OverrideConsuming to provide temporary save/restore of the set_consuming() / get_consuming() flag. It's a good idea to set the consuming flag when retrieving data from an LLEventMailDrop.
2018-05-30MAINT-8686 Viewer should report active coroutines at the end of the sessionandreykproductengine
2017-10-05MAINT-7820 Additional crash loggingandreykproductengine
2016-09-15MAINT-5232: Normalize LLSingleton subclasses.Nat Goodspeed
A shocking number of LLSingleton subclasses had public constructors -- and in several instances, were being explicitly instantiated independently of the LLSingleton machinery. This breaks the new LLSingleton dependency-tracking machinery. It seems only fair that if you say you want an LLSingleton, there should only be ONE INSTANCE! Introduce LLSINGLETON() and LLSINGLETON_EMPTY_CTOR() macros. These handle the friend class LLSingleton<whatevah>; and explicitly declare a private nullary constructor. To try to enforce the LLSINGLETON() convention, introduce a new pure virtual LLSingleton method you_must_use_LLSINGLETON_macro() which is, as you might suspect, defined by the macro. If you declare an LLSingleton subclass without using LLSINGLETON() or LLSINGLETON_EMPTY_CTOR() in the class body, you can't instantiate the subclass for lack of a you_must_use_LLSINGLETON_macro() implementation -- which will hopefully remind the coder. Trawl through ALL LLSingleton subclass definitions, sprinkling in LLSINGLETON() or LLSINGLETON_EMPTY_CTOR() as appropriate. Remove all explicit constructor declarations, public or private, along with relevant 'friend class LLSingleton<myself>' declarations. Where destructors are declared, move them into private section as well. Where the constructor was inline but nontrivial, move out of class body. Fix several LLSingleton abuses revealed by making ctors/dtors private: LLGlobalEconomy was both an LLSingleton and the base class for LLRegionEconomy, a non-LLSingleton. (Therefore every LLRegionEconomy instance contained another instance of the LLGlobalEconomy "singleton.") Extract LLBaseEconomy; LLGlobalEconomy is now a trivial subclass of that. LLRegionEconomy, as you might suspect, now derives from LLBaseEconomy. LLToolGrab, an LLSingleton, was also explicitly instantiated by LLToolCompGun's constructor. Extract LLToolGrabBase, explicitly instantiated, with trivial subclass LLToolGrab, the LLSingleton instance. (WARNING: LLToolGrabBase methods have an unnerving tendency to go after LLToolGrab::getInstance(). I DO NOT KNOW what should be the relationship between the instance in LLToolCompGun and the LLToolGrab singleton instance.) LLGridManager declared a variant constructor accepting (const std::string&), with the comment: // initialize with an explicity grid file for testing. As there is no evidence of this being called from anywhere, delete it. LLChicletBar's constructor accepted an optional (const LLSD&). As the LLSD parameter wasn't used, and as there is no evidence of it being passed from anywhere, delete the parameter. LLViewerWindow::shutdownViews() was checking LLNavigationBar:: instanceExists(), then deleting its getInstance() pointer -- leaving a dangling LLSingleton instance pointer, a land mine if any subsequent code should attempt to reference it. Use deleteSingleton() instead. ~LLAppViewer() was calling LLViewerEventRecorder::instance() and then explicitly calling ~LLViewerEventRecorder() on that instance -- leaving the LLSingleton instance pointer pointing to an allocated-but-destroyed instance. Use deleteSingleton() instead.
2016-09-06MAINT-5232: Ensure that llcoro::get_id() returns distinct values.Nat Goodspeed
Until now, the "main coroutine" (the initial context) of each thread left LLCoros::Current() NULL. The trouble with that is that llcoro::get_id() returns that CoroData* as an opaque token, and we want distinct values for every stack in the process. That would not be true if the "main coroutine" on thread A returned the same value (NULL) as the "main coroutine" on thread B, and so forth. Give each thread's "main coroutine" a dummy heap CoroData instance of its own.
2016-09-03MAINT-5232: Break out LLCoros::get_id() into its own header file.Nat Goodspeed
We need LLSingleton machinery to be able to reference get_id() without also depending on all the rest of LLCoros -- since LLCoros isa LLSingleton.
2016-09-03MAINT-5232: Add LLCoros::get_id() to identify the running coroutine.Nat Goodspeed
Change the module-static thread_specific_ptr to a function-static thread_specific_ptr so it will be initialized on demand -- since LLSingleton will need to rely on get_id(). Note that since LLCoros isa LLSingleton, we must take great care to avoid circularity. Introduce a private helper class LLCoros::Current to obtain and bind that thread_specific_ptr. Change all existing internal references from the static thread_specific_ptr to the new Current helper class.
2016-04-04merge with 4.0.3-releaseOz Linden
2016-01-04MAINT-5976: On Linux builds do not specify explict for bool conversion operator.Rider Linden
2015-12-18MAINT-5976: Fix bug in LLCoros::set_consuming() mechanism.Nat Goodspeed
The original implementation of set_consuming() involved a bool* pointing to a local bool in VoidListener::operator()()'s stack frame. postAndSuspend() would set that bool (through the pointer) as soon as it returned from suspension. The trouble with that is that LLEventMailDrop potentially calls its new listener (fulfilling the future) immediately in the listen_impl() override -- in other words, way up at the top of postAndSuspend(), well before the code that sets the relevant bool. Instead, make the adapter formerly known as VoidListener bind the coroutine's get_consuming() value at adapter construction time (before listening on the LLEventPump), so that its operator()() has the coroutine's correct get_consuming() value to return. Eliminating the bool* makes the code both simpler AND more correct! This change makes that adapter very specific to coroutine usage. Rename it FutureListener and migrate it from lleventcoros.h into the .cpp file. Nobody else was using it anyway. Make corresponding changes to postAndSuspend2() and its WaitForEventOnHelper class -- whose name no longer corresponds to the function as it used to. Rename that one FutureListener2. The new FutureListener functionality, common to both these adapters, makes it useful to derive FutureListener2 from FutureListener. Introduce llmake(), a generic function to deduce template type arguments from function parameter types. This allows us to remove the voidlistener() and wfeoh() helper functions. Hiding VoidListener broke one of the lleventcoro_test.cpp tests. But that test was sort of a lame recap of an earlier implementation of postAndSuspend(), based on LLEventPump events. Recast that test to illustrate how to use a coroutine future to suspend a coroutine for something other than an LLEventPump. But that rubbed my nose in the fact that we MUST wrap future's context switching with proper management of the current coroutine. Introduce LLCoros::Future<T>, which wraps boost::dcoroutines::future<T>. Use LLCoros::Future<T> in postAndSuspend() and postAndSuspend2().
2015-12-16MAINT-5976: Introduce LLCoros::set_consuming(bool).Nat Goodspeed
set_consuming(true) tells each postAndSuspend() call to consume the event for which it is suspending.
2015-11-10remove execute permission from many files that should not have itOz Linden
2015-07-10MAINT-5351: Finish cleaning up messy merge from backing out backoutNat Goodspeed
2015-07-10Automated merge with file:///Users/nat/linden/maint-4952-v-t-uNat Goodspeed
2015-07-10Merge restore of more selfless changesNat Goodspeed
2015-07-10Backed out changeset bab1000e1b2d: restore 'selfless' changesNat Goodspeed
2015-07-10Merge restore of selfless changesNat Goodspeed
2015-07-10Backed out changeset 6e1fa9518747: reapply 'selfless' changesNat Goodspeed
2015-07-10MAINT-5351: Improve management of "current" coroutine information.Nat Goodspeed
Our first cut at tracking the "current" coroutine simply reset the pointer to NULL every time we context-switched away. But that strategy doesn't handle the case of coroutine A launching coroutine B. Introduce LLCoros::CoroData to track, among other things, the previous value of the current-coroutine pointer each time we switch into a coroutine. Restore THAT value when we switch back out.
2015-07-07Backout selfles merge 738255dbbfd679d9e615baab3398e5e345bbb3c5Rider Linden
2015-07-07Backed out selfless mergeRider Linden
2015-07-02MAINT-5357: Introduce and populate llcoro:: namespace.Nat Goodspeed
To date, the coroutine helper functions in lleventcoro.h have been in the global namespace. Migrate them into llcoro namespace, and fix references. Specifically, LLVoidListener => llcoro::VoidListener, and voidlistener(), postAndWait(), both waitForEventOn(), postAndWait2(), errorException() and errorLog() have been moved into llcoro. Also migrate new LLCoros::get_self() and Suspending to llcoro:: namespace. While at it, I realized that -- having converted several lleventcoro.h functions from templates (for arbitrary 'self' parameter type) to ordinary functions, having moved them from lleventcoro.h to lleventcoro.cpp, we can now migrate their helpers from lleventcoro.h to lleventcoro.cpp as well. This eliminates the need for the LLEventDetail namespace; the relevant helpers are now in an anonymous namespace in the .cpp file: listenerNameForCoro(), storeToLLSDPath(), WaitForEventOnHelper and wfeoh().
2015-07-01MAINT-5351: Remove 'self' parameter from coroutine functions.Nat Goodspeed
lleventcoro_test.cpp runs clean (as modified for new API), and all the rest builds clean, but the resulting viewer is as yet untested.
2015-07-01MAINT-5351: Remove Boost Preprocessor headers from llcoros.h.Nat Goodspeed
These were used in a former iteration (when we explicitly forwarded parameters), but are no longer needed.
2013-05-23MAINT-2724: Make viewer explicitly set coroutine stack size.Nat Goodspeed
Introduce LLCoros::setStackSize(), with a compile-time default value we hope we never have to use. Make LLAppViewer call it with the value of the new settings variable CoroutineStackSize as soon as we've read settings files. (While we're at it, notify interested parties that we've read settings files.) Give CoroutineStackSize a default value four times the previous default stack size. Make LLCoros::launch() pass the saved stack size to each new coroutine instance. Re-enable lleventcoro integration test. Use LLSDMap() construct rather than LLSD::insert(), which used to return the modified object but is now void.
2013-05-07merge changes for DRTVWR-299Oz Linden
2013-03-29Update Mac and Windows breakpad builds to latestGraham Madarasz
2013-02-21MAINT-2389: Change viewer to Boost package without ucontext.h.Nat Goodspeed
In autobuild.xml, specify today's build of the Boost package that includes the Boost.Context library, and whose boost::dcoroutines library uses Boost.Context exclusively instead of its previous context-switching underpinnings (source of the ucontext.h dependency). Add BOOST_CONTEXT_LIBRARY to Boost.cmake and Copy3rdPartyLibs.cmake. Link it with the viewer and with the lllogin.cpp test executable. Track new Boost package convention that our (early, unofficial) Boost.Coroutine library is now accessed as boost/dcoroutine/etc.h and boost::dcoroutines::etc. Remove #include <boost/coroutine/coroutine.hpp> from llviewerprecompiledheaders.h and lllogin.cpp: old rule that Boost.Coroutine header must be #included before anything else that might use ucontext.h is gone now that we no longer depend on ucontext.h. In fact remove -D_XOPEN_SOURCE in 00-Common.cmake because that was inserted specifically to work around a known problem with the ucontext.h facilities.
2010-08-13Change license from GPL to LGPL (version 2.1)Oz Linden
2009-11-18Switch some files to Unix line endingsBryan O'Sullivan