diff options
Diffstat (limited to 'indra/llcommon/lleventcoro.cpp')
| -rwxr-xr-x | indra/llcommon/lleventcoro.cpp | 208 |
1 files changed, 192 insertions, 16 deletions
diff --git a/indra/llcommon/lleventcoro.cpp b/indra/llcommon/lleventcoro.cpp index 81cc33fbba..66cc7cada0 100755 --- a/indra/llcommon/lleventcoro.cpp +++ b/indra/llcommon/lleventcoro.cpp @@ -34,38 +34,63 @@ #include <map> // std headers // external library headers +#include <boost/dcoroutine/coroutine.hpp> +#include <boost/dcoroutine/future.hpp> // other Linden headers #include "llsdserialize.h" #include "llerror.h" #include "llcoros.h" -std::string LLEventDetail::listenerNameForCoroImpl(const void* self_id) +namespace { - // First, if this coroutine was launched by LLCoros::launch(), find that name. - std::string name(LLCoros::instance().getNameByID(self_id)); + +/** + * waitForEventOn() permits a coroutine to temporarily listen on an + * LLEventPump any number of times. We don't really want to have to ask + * the caller to label each such call with a distinct string; the whole + * point of waitForEventOn() is to present a nice sequential interface to + * the underlying LLEventPump-with-named-listeners machinery. So we'll use + * LLEventPump::inventName() to generate a distinct name for each + * temporary listener. On the other hand, because a given coroutine might + * call waitForEventOn() any number of times, we don't really want to + * consume an arbitrary number of generated inventName()s: that namespace, + * though large, is nonetheless finite. So we memoize an invented name for + * each distinct coroutine instance. + */ +std::string listenerNameForCoro() +{ + // If this coroutine was launched by LLCoros::launch(), find that name. + std::string name(LLCoros::instance().getName()); if (! name.empty()) { return name; } - // Apparently this coroutine wasn't launched by LLCoros::launch(). Check - // whether we have a memo for this self_id. - typedef std::map<const void*, std::string> MapType; - static MapType memo; - MapType::const_iterator found = memo.find(self_id); - if (found != memo.end()) - { - // this coroutine instance has called us before, reuse same name - return found->second; - } // this is the first time we've been called for this coroutine instance name = LLEventPump::inventName("coro"); - memo[self_id] = name; - LL_INFOS("LLEventCoro") << "listenerNameForCoroImpl(" << self_id << "): inventing coro name '" + LL_INFOS("LLEventCoro") << "listenerNameForCoro(): inventing coro name '" << name << "'" << LL_ENDL; return name; } -void LLEventDetail::storeToLLSDPath(LLSD& dest, const LLSD& rawPath, const LLSD& value) +/** + * Implement behavior described for postAndWait()'s @a replyPumpNamePath + * parameter: + * + * * If <tt>path.isUndefined()</tt>, do nothing. + * * If <tt>path.isString()</tt>, @a dest is an LLSD map: store @a value + * into <tt>dest[path.asString()]</tt>. + * * If <tt>path.isInteger()</tt>, @a dest is an LLSD array: store @a + * value into <tt>dest[path.asInteger()]</tt>. + * * If <tt>path.isArray()</tt>, iteratively apply the rules above to step + * down through the structure of @a dest. The last array entry in @a + * path specifies the entry in the lowest-level structure in @a dest + * into which to store @a value. + * + * @note + * In the degenerate case in which @a path is an empty array, @a dest will + * @em become @a value rather than @em containing it. + */ +void storeToLLSDPath(LLSD& dest, const LLSD& rawPath, const LLSD& value) { if (rawPath.isUndefined()) { @@ -118,6 +143,155 @@ void LLEventDetail::storeToLLSDPath(LLSD& dest, const LLSD& rawPath, const LLSD& *pdest = value; } +} // anonymous + +void llcoro::yield() +{ + // By viewer convention, we post an event on the "mainloop" LLEventPump + // each iteration of the main event-handling loop. So waiting for a single + // event on "mainloop" gives us a one-frame yield. + waitForEventOn("mainloop"); +} + +LLSD llcoro::postAndWait(const LLSD& event, const LLEventPumpOrPumpName& requestPump, + const LLEventPumpOrPumpName& replyPump, const LLSD& replyPumpNamePath) +{ + // declare the future + boost::dcoroutines::future<LLSD> future(LLCoros::get_self()); + // make a callback that will assign a value to the future, and listen on + // the specified LLEventPump with that callback + std::string listenerName(listenerNameForCoro()); + LLTempBoundListener connection( + replyPump.getPump().listen(listenerName, + voidlistener(boost::dcoroutines::make_callback(future)))); + // skip the "post" part if requestPump is default-constructed + if (requestPump) + { + // If replyPumpNamePath is non-empty, store the replyPump name in the + // request event. + LLSD modevent(event); + storeToLLSDPath(modevent, replyPumpNamePath, replyPump.getPump().getName()); + LL_DEBUGS("lleventcoro") << "postAndWait(): coroutine " << listenerName + << " posting to " << requestPump.getPump().getName() + << LL_ENDL; + + // *NOTE:Mani - Removed because modevent could contain user's hashed passwd. + // << ": " << modevent << LL_ENDL; + requestPump.getPump().post(modevent); + } + LL_DEBUGS("lleventcoro") << "postAndWait(): coroutine " << listenerName + << " about to wait on LLEventPump " << replyPump.getPump().getName() + << LL_ENDL; + // trying to dereference ("resolve") the future makes us wait for it + LLSD value; + { + // instantiate Suspending to manage the "current" coroutine + llcoro::Suspending suspended; + value = *future; + } // destroy Suspending as soon as we're back + LL_DEBUGS("lleventcoro") << "postAndWait(): coroutine " << listenerName + << " resuming with " << value << LL_ENDL; + // returning should disconnect the connection + return value; +} + +namespace +{ + +/** + * This helper is specifically for the two-pump version of waitForEventOn(). + * We use a single future object, but we want to listen on two pumps with it. + * Since we must still adapt from (the callable constructed by) + * boost::dcoroutines::make_callback() (void return) to provide an event + * listener (bool return), we've adapted VoidListener for the purpose. The + * basic idea is that we construct a distinct instance of WaitForEventOnHelper + * -- binding different instance data -- for each of the pumps. Then, when a + * pump delivers an LLSD value to either WaitForEventOnHelper, it can combine + * that LLSD with its discriminator to feed the future object. + */ +template <typename LISTENER> +class WaitForEventOnHelper +{ +public: + WaitForEventOnHelper(const LISTENER& listener, int discriminator): + mListener(listener), + mDiscrim(discriminator) + {} + // this signature is required for an LLEventPump listener + bool operator()(const LLSD& event) + { + // our future object is defined to accept LLEventWithID + mListener(LLEventWithID(event, mDiscrim)); + // don't swallow the event, let other listeners see it + return false; + } +private: + LISTENER mListener; + const int mDiscrim; +}; + +/// WaitForEventOnHelper type-inference helper +template <typename LISTENER> +WaitForEventOnHelper<LISTENER> wfeoh(const LISTENER& listener, int discriminator) +{ + return WaitForEventOnHelper<LISTENER>(listener, discriminator); +} + +} // anonymous + +namespace llcoro +{ + +LLEventWithID postAndWait2(const LLSD& event, + const LLEventPumpOrPumpName& requestPump, + const LLEventPumpOrPumpName& replyPump0, + const LLEventPumpOrPumpName& replyPump1, + const LLSD& replyPump0NamePath, + const LLSD& replyPump1NamePath) +{ + // declare the future + boost::dcoroutines::future<LLEventWithID> future(LLCoros::get_self()); + // either callback will assign a value to this future; listen on + // each specified LLEventPump with a callback + std::string name(listenerNameForCoro()); + LLTempBoundListener connection0( + replyPump0.getPump().listen(name + "a", + wfeoh(boost::dcoroutines::make_callback(future), 0))); + LLTempBoundListener connection1( + replyPump1.getPump().listen(name + "b", + wfeoh(boost::dcoroutines::make_callback(future), 1))); + // skip the "post" part if requestPump is default-constructed + if (requestPump) + { + // If either replyPumpNamePath is non-empty, store the corresponding + // replyPump name in the request event. + LLSD modevent(event); + storeToLLSDPath(modevent, replyPump0NamePath, + replyPump0.getPump().getName()); + storeToLLSDPath(modevent, replyPump1NamePath, + replyPump1.getPump().getName()); + LL_DEBUGS("lleventcoro") << "postAndWait2(): coroutine " << name + << " posting to " << requestPump.getPump().getName() + << ": " << modevent << LL_ENDL; + requestPump.getPump().post(modevent); + } + LL_DEBUGS("lleventcoro") << "postAndWait2(): coroutine " << name + << " about to wait on LLEventPumps " << replyPump0.getPump().getName() + << ", " << replyPump1.getPump().getName() << LL_ENDL; + // trying to dereference ("resolve") the future makes us wait for it + LLEventWithID value; + { + // instantiate Suspending to manage "current" coroutine + llcoro::Suspending suspended; + value = *future; + } // destroy Suspending as soon as we're back + LL_DEBUGS("lleventcoro") << "postAndWait(): coroutine " << name + << " resuming with (" << value.first << ", " << value.second << ")" + << LL_ENDL; + // returning should disconnect both connections + return value; +} + LLSD errorException(const LLEventWithID& result, const std::string& desc) { // If the result arrived on the error pump (pump 1), instead of @@ -144,3 +318,5 @@ LLSD errorLog(const LLEventWithID& result, const std::string& desc) // A simple return must therefore be from the reply pump (pump 0). return result.first; } + +} // namespace llcoro |