/** * @file _httprequestqueue.h * @brief Internal declaration for the operation request queue * * $LicenseInfo:firstyear=2012&license=viewerlgpl$ * Second Life Viewer Source Code * Copyright (C) 2012, Linden Research, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; * version 2.1 of the License only. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA * * Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA * $/LicenseInfo$ */ #ifndef _LLCORE_HTTP_REQUEST_QUEUE_H_ #define _LLCORE_HTTP_REQUEST_QUEUE_H_ #include <vector> #include "httpcommon.h" #include "_refcounted.h" #include "_mutex.h" namespace LLCore { class HttpOperation; /// Thread-safe queue of HttpOperation objects. Just /// a simple queue that handles the transfer of operation /// requests from all HttpRequest instances into the /// singleton HttpService instance. class HttpRequestQueue : public LLCoreInt::RefCounted { protected: /// Caller acquires a Refcount on construction HttpRequestQueue(); protected: virtual ~HttpRequestQueue(); // Use release() private: HttpRequestQueue(const HttpRequestQueue &); // Not defined void operator=(const HttpRequestQueue &); // Not defined public: typedef boost::shared_ptr<HttpOperation> opPtr_t; static void init(); static void term(); /// Threading: callable by any thread once inited. inline static HttpRequestQueue * instanceOf() { return sInstance; } public: typedef std::vector<opPtr_t> OpContainer; /// Insert an object at the back of the request queue. /// /// Caller must provide one refcount to the queue which takes /// possession of the count on success. /// /// @return Standard status. On failure, caller /// must dispose of the operation with /// an explicit release() call. /// /// Threading: callable by any thread. HttpStatus addOp(const opPtr_t &op); /// Return the operation on the front of the queue. If /// the queue is empty and @wait is false, call returns /// immediately and a NULL pointer is returned. If true, /// caller will sleep until explicitly woken. Wakeups /// can be spurious and callers must expect NULL pointers /// even if waiting is indicated. /// /// Caller acquires reference count any returned operation /// /// Threading: callable by any thread. opPtr_t fetchOp(bool wait); /// Return all queued requests to caller. The @ops argument /// should be empty when called and will be swap()'d with /// current contents. Handling of the @wait argument is /// identical to @fetchOp. /// /// Caller acquires reference count on each returned operation /// /// Threading: callable by any thread. void fetchAll(bool wait, OpContainer & ops); /// Wake any sleeping threads. Normal queuing operations /// won't require this but it may be necessary for termination /// requests. /// /// Threading: callable by any thread. void wakeAll(); /// Disallow further request queuing. Callers to @addOp will /// get a failure status (LLCORE, HE_SHUTTING_DOWN). Callers /// to @fetchAll or @fetchOp will get requests that are on the /// queue but the calls will no longer wait. Instead they'll /// return immediately. Also wakes up all sleepers to send /// them on their way. /// /// Threading: callable by any thread. void stopQueue(); protected: static HttpRequestQueue * sInstance; protected: OpContainer mQueue; LLCoreInt::HttpMutex mQueueMutex; LLCoreInt::HttpConditionVariable mQueueCV; bool mQueueStopped; }; // end class HttpRequestQueue } // end namespace LLCore #endif // _LLCORE_HTTP_REQUEST_QUEUE_H_