/* -*- C++ -*- */ // $Id$ // ============================================================================ // // = LIBRARY // ace // // = FILENAME // ACE_Strategies_T.h // // = AUTHOR // Doug Schmidt // // ============================================================================ #if !defined (ACE_STRATEGIES_T_H) #define ACE_STRATEGIES_T_H #include "ace/Strategies.h" #include "ace/Service_Config.h" #include "ace/Reactor.h" #include "ace/Synch_Options.h" #include "ace/Hash_Map_Manager.h" template class ACE_Recycling_Strategy { // = TITLE // Defines the interface (and default implementation) for // specifying a recycling strategy for a SVC_HANDLER. // // = DESCRIPTION // Acts as a consular to the Svc_Handler, preparing it for the // tough times ahead when the Svc_Handler will be recycled. public: virtual ~ACE_Recycling_Strategy (void); // Virtual Destructor virtual int assign_recycler (SVC_HANDLER *svc_handler, ACE_Connection_Recycling_Strategy *recycler, const void *recycling_act); // Tell the Svc_Handler something about the recycler, so that it can // reach the recycler when necessary. virtual int prepare_for_recycling (SVC_HANDLER *svc_handler); // This allows us to prepare the svc_handler for recycling. }; template class ACE_Creation_Strategy { // = TITLE // Defines the interface for specifying a creation strategy for // a SVC_HANDLER. // // = DESCRIPTION // The default behavior is to make a new SVC_HANDLER. However, // subclasses can override this strategy to perform SVC_HANDLER // creation in any way that they like (such as creating subclass // instances of SVC_HANDLER, using a singleton, dynamically // linking the handler, etc.). public: // = Initialization and termination methods. ACE_Creation_Strategy (ACE_Thread_Manager * = 0); // Default constructor. int open (ACE_Thread_Manager * = 0); // A is useful when creating active objects. virtual ~ACE_Creation_Strategy (void); // = Factory method. virtual int make_svc_handler (SVC_HANDLER *&sh); // Create a SVC_HANDLER with the appropriate creation strategy. The // default behavior of this method is to make a new if // == 0 (passing in the ), else is // unchanged. Returns -1 on failure, else 0. void dump (void) const; // Dump the state of an object. ACE_ALLOC_HOOK_DECLARE; // Declare the dynamic allocation hooks. protected: ACE_Thread_Manager *thr_mgr_; // Pointer to a thread manager. }; template class ACE_Singleton_Strategy : public ACE_Creation_Strategy { // = TITLE // Defines the interface for specifying a creation strategy for // a that always returns the same (i.e., // it's a Singleton). // // = DESCRIPTION // Note that this class takes over the ownership of the // SVC_HANDLER passed into it as a parameter and it becomes // responsible for deleting this object. public: // = Initialization and termination methods. ACE_Singleton_Strategy (SVC_HANDLER * = 0, ACE_Thread_Manager * = 0); int open (SVC_HANDLER *, ACE_Thread_Manager * = 0); virtual ~ACE_Singleton_Strategy (void); // = Factory method. virtual int make_svc_handler (SVC_HANDLER *&); // Create a Singleton SVC_HANDLER by always returning the same // SVC_HANDLER. Returns -1 on failure, else 0. void dump (void) const; // Dump the state of an object. ACE_ALLOC_HOOK_DECLARE; // Declare the dynamic allocation hooks. protected: SVC_HANDLER *svc_handler_; // Pointer to the Singleton svc_handler. }; template class ACE_DLL_Strategy : public ACE_Creation_Strategy { // = TITLE // Defines the interface for specifying a creation strategy for // a SVC_HANDLER based on dynamic linking of the SVC_HANDLER. public: // = Intialization and termination methods. ACE_DLL_Strategy (void); // "Do-nothing" constructor. ACE_DLL_Strategy (const char dll_name[], const char factory_function[], const char svc_name[], ACE_Service_Repository *, ACE_Thread_Manager * = 0); // Initialize the DLL strategy based upon the service's DLL // information contained in the string. int open (const char dll_name[], const char factory_function[], const char svc_name[], ACE_Service_Repository *, ACE_Thread_Manager * = 0); // Initialize the DLL strategy based upon the service's DLL // information contained in the string. // = Factory method. virtual int make_svc_handler (SVC_HANDLER *&); // Create a SVC_HANDLER by dynamically linking it from a DLL. // Returns -1 on failure, else 0. void dump (void) const; // Dump the state of an object. ACE_ALLOC_HOOK_DECLARE; // Declare the dynamic allocation hooks. protected: typedef ACE_Creation_Strategy inherited; char dll_name_[MAXPATHLEN + 1]; // Name of the DLL to dynamically link. char factory_function_[MAXPATHLEN + 1]; // Name of the factory function in the shared library to use to // obtain a pointer to the new SVC_HANDLER. char svc_name_[MAXNAMELEN + 1]; // Name of the service. ACE_Service_Repository *svc_rep_; // Pointer to the . }; template class ACE_Concurrency_Strategy { // = TITLE // Defines the interface for specifying a concurrency strategy // for a SVC_HANDLER. // // = DESCRIPTION // Default behavior is to activate the SVC_HANDLER by calling // its open() method (which allows the SVC_HANDLER to define its // own concurrency strategy). However, subclasses can override // this default strategy to do more sophisticated concurrency // activations (such as creating the SVC_HANDLER as an active // object via multi-threading or multi-processing). public: ACE_Concurrency_Strategy (int flags = 0); // Constructor // = Factory method. virtual int activate_svc_handler (SVC_HANDLER *svc_handler, void *arg = 0); // Activate the with an appropriate concurrency // strategy. The default behavior of this method is to activate the // SVC_HANDLER by calling its open() method (which allows the // SVC_HANDLER to define its own concurrency strategy). virtual ~ACE_Concurrency_Strategy (void); void dump (void) const; // Dump the state of an object. ACE_ALLOC_HOOK_DECLARE; // Declare the dynamic allocation hooks. protected: int flags_; // Flags that are parsed to set options for the connected // . }; template class ACE_Reactive_Strategy : public ACE_Concurrency_Strategy { // = TITLE // Defines the interface for specifying a Reactive concurrency // strategy for a SVC_HANDLER. // // = DESCRIPTION // This class provides a strategy that registers the // with a . public: // = Intialization and termination methods. ACE_Reactive_Strategy (int flags = 0); // "Do-nothing constructor" ACE_Reactive_Strategy (ACE_Reactor *reactor, ACE_Reactor_Mask = ACE_Event_Handler::READ_MASK, int flags = 0); // Initialize the strategy. virtual int open (ACE_Reactor *reactor, ACE_Reactor_Mask = ACE_Event_Handler::READ_MASK, int flags = 0); // Initialize the strategy. virtual ~ACE_Reactive_Strategy (void); // Destructor. // = Factory method. virtual int activate_svc_handler (SVC_HANDLER *svc_handler, void *arg = 0); // Activate the by registering it with the // and then calling it's hook. void dump (void) const; // Dump the state of an object. ACE_ALLOC_HOOK_DECLARE; // Declare the dynamic allocation hooks. protected: typedef ACE_Concurrency_Strategy inherited; ACE_Reactor *reactor_; // Pointer to the Reactor we'll use to register the . ACE_Reactor_Mask mask_; // The mask that we pass to the when we register the // . }; template class ACE_Thread_Strategy : public ACE_Concurrency_Strategy { // = TITLE // Defines the interface for specifying a concurrency strategy // for a based on multithreading. // // = DESCRIPTION // This class provides a strategy that manages the creation of // threads to handle requests from clients concurrently. It // behaves as a "thread factory", spawning threads "on-demand" // to run the service specified by a user-supplied // . public: // = Intialization and termination methods. ACE_Thread_Strategy (int flags = 0); // "Do-nothing constructor" ACE_Thread_Strategy (ACE_Thread_Manager *tm, long thr_flags, size_t n_threads = 1, int flags = 0); // Initialize the strategy. virtual int open (ACE_Thread_Manager *tm, long thr_flags, size_t n_threads = 1, int flags = 0); // Initialize the strategy. virtual ~ACE_Thread_Strategy (void); // = Factory method. virtual int activate_svc_handler (SVC_HANDLER *svc_handler, void *arg = 0); // Activate the with an appropriate concurrency // strategy. This method activates the SVC_HANDLER by first calling // its open() method and then calling its activate() method to turn // it into an active object. void dump (void) const; // Dump the state of an object. ACE_ALLOC_HOOK_DECLARE; // Declare the dynamic allocation hooks. protected: typedef ACE_Concurrency_Strategy inherited; ACE_Thread_Manager *thr_mgr_; // Thread manager for this class (must be provided). long thr_flags_; // Flags to pass into the SVC_HANDLER::activate() method. size_t n_threads_; // Number of threads to spawn. }; template class ACE_Process_Strategy : public ACE_Concurrency_Strategy { // = TITLE // Defines the interface for specifying a concurrency strategy // for a based on multiprocessing. // // = DESCRIPTION // This class provides a strategy that manages the creation of // processes to handle requests from clients concurrently. It // behaves as a "process factory", forking threads "on-demand" // to run the service specified by a user-supplied // . public: // = Intialization and termination methods. ACE_Process_Strategy (size_t n_processes = 1, ACE_Event_Handler *acceptor = 0, ACE_Reactor * = 0, int flags = 0); // Initialize the strategy. virtual int open (size_t n_processes = 1, ACE_Event_Handler *acceptor = 0, ACE_Reactor * = 0, int flag = 0); // Initialize the strategy. virtual ~ACE_Process_Strategy (void); // = Factory method. virtual int activate_svc_handler (SVC_HANDLER *svc_handler, void *arg = 0); // Activate the with an appropriate concurrency // strategy. This method activates the SVC_HANDLER by first forking // and then calling the open() method of the SVC_HANDLER in the // child. void dump (void) const; // Dump the state of an object. ACE_ALLOC_HOOK_DECLARE; // Declare the dynamic allocation hooks. protected: typedef ACE_Concurrency_Strategy inherited; size_t n_processes_; // Number of processes to spawn. ACE_Event_Handler *acceptor_; // This is the in the parent is listening on. We need to // make sure that we remove it from the Reactor and close it down in // the child. ACE_Reactor *reactor_; // This is the the child is using in conjunction with the // . We need to remove the from this // in the child. }; template class ACE_Accept_Strategy { // = TITLE // Defines the interface for specifying a passive connection // acceptance strategy for a SVC_HANDLER. // // = DESCRIPTION // This class provides a strategy that manages passive // connection acceptance of a client. public: // = Initialization and termination methods. ACE_Accept_Strategy (ACE_Reactor *reactor = ACE_Reactor::instance ()); // Default constructor. ACE_Accept_Strategy (const ACE_PEER_ACCEPTOR_ADDR &local_addr, int restart = 0, ACE_Reactor *reactor = ACE_Reactor::instance ()); // Initialize the with . virtual int open (const ACE_PEER_ACCEPTOR_ADDR &local_addr, int restart = 0); // Initialize the with . virtual ACE_HANDLE get_handle (void) const; // Return the underlying ACE_HANDLE of the . virtual ACE_PEER_ACCEPTOR &acceptor (void) const; // Return a reference to the . virtual ~ACE_Accept_Strategy (void); // = Factory method. virtual int accept_svc_handler (SVC_HANDLER *); // The default behavior delegates to the method of the // PEER_ACCEPTOR. void dump (void) const; // Dump the state of an object. ACE_ALLOC_HOOK_DECLARE; // Declare the dynamic allocation hooks. protected: ACE_PEER_ACCEPTOR acceptor_; // Factory that establishes connections passively. ACE_Reactor *reactor_; // Pointer to the reactor used by the Acceptor. }; template class ACE_Connect_Strategy { // = TITLE // Defines the interface for specifying an active // connection establishment strategy for a SVC_HANDLER. // // = DESCRIPTION // This class provides a strategy that manages active // connection establishment to a server. public: // = Initialization and termination methods. ACE_Connect_Strategy (void); // Default constructor. virtual ACE_PEER_CONNECTOR &connector (void) const; // Return a reference to the . virtual ~ACE_Connect_Strategy (void); // = Factory method. virtual int connect_svc_handler (SVC_HANDLER *&sh, const ACE_PEER_CONNECTOR_ADDR &remote_addr, ACE_Time_Value *timeout, const ACE_PEER_CONNECTOR_ADDR &local_addr, int reuse_addr, int flags, int perms); // The default behavior delegates to the method of the // . void dump (void) const; // Dump the state of an object. ACE_ALLOC_HOOK_DECLARE; // Declare the dynamic allocation hooks. protected: ACE_PEER_CONNECTOR connector_; // Factory that establishes connections actively. }; template class ACE_Scheduling_Strategy { // = TITLE // Defines the interface for specifying how to suspend and // resume a service . // // = DESCRIPTION // This class provides a strategy that allows arbitrarily // sophisticated service suspension and resumption. The default // behavior is to do nothing... public: // = Initialization and termination methods. ACE_Scheduling_Strategy (SVC_HANDLER * = 0); // Constructor virtual ~ACE_Scheduling_Strategy (void); // Destructor // = Scheduling methods virtual int suspend (void); // Suspend hook. virtual int resume (void); // Resume hook. virtual void dump (void) const; // Dump the state of the object. protected: SVC_HANDLER *scheduler_; // Points to the scheduler strategy object... int delete_scheduler_; // Keeps track of whether we need to delete this or not... }; template class ACE_NOOP_Creation_Strategy : public ACE_Creation_Strategy { // = TITLE // Implements a no-op creation strategy in order to defer // decisions regarding creation to some later point in time, such // as in connect or accept strategy. // // = DESCRIPTION // An example of the use of this is in the // , which only returns a single // connection for a given endpoint. public: virtual int make_svc_handler (SVC_HANDLER *&); // This is a no-op. }; template class ACE_NOOP_Concurrency_Strategy : public ACE_Concurrency_Strategy { // = TITLE // Implements a no-op activation strategy in order to avoid // calling open on a svc_handler multiple times. // // = DESCRIPTION // An example of the use of this is in the // , which reuses svc_handlers. // Therefore we don't want to call open on the recycled // svc_handler more than once. public: // = Factory method. virtual int activate_svc_handler (SVC_HANDLER *svc_handler, void *arg = 0); // This is a no-op. }; template class ACE_Hash_Addr { // = TITLE // Internal class to compute hash values on addresses in // . // // = DESCRIPTION // Intended to be used as a key to an . // parameter/subclass is typically . It // is expected to implement operator==(). public: // = Initialization methods. ACE_Hash_Addr (void); // Default constructor. ACE_Hash_Addr (const ADDR_T &a); // Pre-compute hash value. ACE_Hash_Addr (const ADDR_T &a, int recyclable); // Pre-compute hash value. u_long hash (void) const; // Computes and returns hash value. This "caches" the hash value to // improve performance. int operator== (const ACE_Hash_Addr &rhs) const; // Compares two hash values. // = Set/Get the recyclable bit int recyclable (void) const; void recyclable (int new_value); private: size_t hash_i (const ADDR_T &) const; // This is the method that actually performs the non-cached hash // computation. It should typically be specialized. u_long hash_value_; // Pre-computed hash-value. int recyclable_; // We need to know if the is "in-use". If it is, we // can operator==() can skip the comparison. ADDR_T addr_; // The underlying address. }; template class ACE_Cached_Connect_Strategy : public ACE_Connection_Recycling_Strategy, public ACE_Connect_Strategy { // = TITLE // A connection strategy which caches connections to peers // (represented by instances), thereby allowing // subsequent re-use of unused, but available, connections. // // = DESCRIPTION // is intended to be used as a // plug-in connection strategy for . // It's added value is re-use of established connections. // // = USAGE // In order to use this appropriately, the user must provide // a template specialization for and // based on the address type and the // service handler type. For example, a specialization using // and might be: // = BEGIN // = BEGIN // size_t // ACE_Hash_Addr::hash_i(const ACE_INET_Addr &a) // { // return ...; // } // = END // = END // // = SEE ALSO // . public: ACE_Cached_Connect_Strategy (ACE_Creation_Strategy *cre_s = 0, ACE_Concurrency_Strategy *con_s = 0, ACE_Recycling_Strategy *rec_s = 0); // Constructor virtual ~ACE_Cached_Connect_Strategy (void); // Destructor virtual int open (ACE_Creation_Strategy *cre_s, ACE_Concurrency_Strategy *con_s, ACE_Recycling_Strategy *rec_s); // This methods allow you to change the strategies used by the // cached connector. virtual int make_svc_handler (SVC_HANDLER *&sh); // Template method for making a new virtual int activate_svc_handler (SVC_HANDLER *svc_handler); // Template method for activating a new virtual int assign_recycler (SVC_HANDLER *svc_handler, ACE_Connection_Recycling_Strategy *recycler, const void *recycling_act); // Template method for setting the recycler information of the // svc_handler. virtual int prepare_for_recycling (SVC_HANDLER *svc_handler); // Template method for preparing the svc_handler for recycling. virtual int connect_svc_handler (SVC_HANDLER *&sh, const ACE_PEER_CONNECTOR_ADDR &remote_addr, ACE_Time_Value *timeout, const ACE_PEER_CONNECTOR_ADDR &local_addr, int reuse_addr, int flags, int perms); // Checks to see if there is already a in the cache // connected to the . If so, we return this pointer. // Otherwise we establish the connection, put it into the cache, and // return the pointer. // <[NOTE]>: the <{reuse_addr}> argument does NOT control re-use of // addresses in the cache. Rather, if the underlying protocol // requires a "dead time" prior to re-use of its addresses (TCP // is a classic example of this), <{and}> the protocol provides a means // by which to defeat the dead time, setting this argument to non-zero // will defeat the dead-time requirement. <{Dev. Note: We might want // to consider enhancing the interface at some point so that this also // controls re-use of the cache.}> virtual int purge (const void *recycling_act); // Remove from cache. virtual int cache (const void *recycling_act); // Add to cache. private: // = Define some useful typedefs. typedef ACE_Creation_Strategy CREATION_STRATEGY; typedef ACE_Concurrency_Strategy CONCURRENCY_STRATEGY; typedef ACE_Recycling_Strategy RECYCLING_STRATEGY; // = Super class typedef ACE_Connect_Strategy CONNECT_STRATEGY; // = Typedefs for managing the map typedef ACE_Hash_Addr ADDRESS; typedef ACE_Hash_Map_Manager CONNECTION_MAP; typedef ACE_Hash_Map_Iterator CONNECTION_MAP_ITERATOR; typedef ACE_Hash_Map_Entry CONNECTION_MAP_ENTRY; CONNECTION_MAP connection_cache_; // Table that maintains the cache of connected s. MUTEX lock_; // Mutual exclusion for this object. // = Strategy objects. CREATION_STRATEGY *creation_strategy_; // Creation strategy for an . int delete_creation_strategy_; // 1 if created the creation strategy and thus should // delete it, else 0. CONCURRENCY_STRATEGY *concurrency_strategy_; // Concurrency strategy for an . int delete_concurrency_strategy_; // 1 if created the concurrency strategy and thus should // delete it, else 0. RECYCLING_STRATEGY *recycling_strategy_; // Recycling strategy for an . int delete_recycling_strategy_; // 1 if created the recycling strategy and thus should // delete it, else 0. }; template class ACE_Schedule_All_Reactive_Strategy : public ACE_Scheduling_Strategy { // = TITLE // Defines the interface for specifying how to suspend and // resume a single-threaded reactive service . // // = DESCRIPTION // This class provides a strategy that suspends and resumes all // the Event_Handlers in a Reactor in one fell swoop. public: // = Initialization and termination methods. ACE_Schedule_All_Reactive_Strategy (SVC_HANDLER * = 0); // Constructor // = Scheduling methods virtual int suspend (void); // Suspend hook. virtual int resume (void); // Resume hook. virtual void dump (void) const; // Dump the state of the object. }; template class ACE_Schedule_All_Threaded_Strategy : public ACE_Scheduling_Strategy { // = TITLE // Defines the interface for specifying how to suspend and // resume a multithreaded service . // // = DESCRIPTION // This class provides a strategy that suspends and resumes all // the Event_Handlers controlled by a Thread_Manager in one fell swoop. public: // = Initialization and termination methods. ACE_Schedule_All_Threaded_Strategy (SVC_HANDLER * = 0); // Constructor // = Scheduling methods virtual int suspend (void); // Suspend hook. virtual int resume (void); // Resume hook. virtual void dump (void) const; // Dump the state of the object. }; #if defined (ACE_TEMPLATES_REQUIRE_SOURCE) #include "ace/Strategies_T.cpp" #endif /* ACE_TEMPLATES_REQUIRE_SOURCE */ #if defined (ACE_TEMPLATES_REQUIRE_PRAGMA) #pragma implementation ("Strategies_T.cpp") #endif /* ACE_TEMPLATES_REQUIRE_PRAGMA */ #endif /* ACE_STRATEGIES_T_H */