Merge pull request #2809 from sigiesec/optimize-select-win

Optimize select on Windows; reduce code duplication in select_t

src/select.hpp

@@ -53,122 +53,130 @@
 
 namespace zmq
 {
+struct i_poll_events;
 
-    struct i_poll_events;
+//  Implements socket polling mechanism using POSIX.1-2001 select()
+//  function.
 
-    //  Implements socket polling mechanism using POSIX.1-2001 select()
-    //  function.
+class select_t : public poller_base_t
+{
+  public:
+    typedef fd_t handle_t;
 
-    class select_t : public poller_base_t
-    {
-    public:
+    select_t (const ctx_t &ctx_);
+    ~select_t ();
 
-        typedef fd_t handle_t;
+    //  "poller" concept.
+    handle_t add_fd (fd_t fd_, zmq::i_poll_events *events_);
+    void rm_fd (handle_t handle_);
+    void set_pollin (handle_t handle_);
+    void reset_pollin (handle_t handle_);
+    void set_pollout (handle_t handle_);
+    void reset_pollout (handle_t handle_);
+    void start ();
+    void stop ();
 
-        select_t (const ctx_t &ctx_);
-        ~select_t ();
+    static int max_fds ();
 
-        //  "poller" concept.
-        handle_t add_fd (fd_t fd_, zmq::i_poll_events *events_);
-        void rm_fd (handle_t handle_);
-        void set_pollin (handle_t handle_);
-        void reset_pollin (handle_t handle_);
-        void set_pollout (handle_t handle_);
-        void reset_pollout (handle_t handle_);
-        void start ();
-        void stop ();
+  private:
+    //  Main worker thread routine.
+    static void worker_routine (void *arg_);
 
-        static int max_fds ();
+    //  Main event loop.
+    void loop ();
 
-    private:
+    //  Reference to ZMQ context.
+    const ctx_t &ctx;
 
-        //  Main worker thread routine.
-        static void worker_routine (void *arg_);
+    //  Internal state.
+    struct fds_set_t
+    {
+        fds_set_t ();
+        fds_set_t (const fds_set_t &other_);
+        fds_set_t &operator= (const fds_set_t &other_);
+        //  Convenience method to descriptor from all sets.
+        void remove_fd (const fd_t &fd_);
+
+        fd_set read;
+        fd_set write;
+        fd_set error;
+    };
 
-        //  Main event loop.
-        void loop ();
+    struct fd_entry_t
+    {
+        fd_t fd;
+        zmq::i_poll_events *events;
+    };
+    typedef std::vector<fd_entry_t> fd_entries_t;
 
-        //  Reference to ZMQ context.
-        const ctx_t &ctx;
+    void trigger_events (const fd_entries_t &fd_entries_,
+                         const fds_set_t &local_fds_set_,
+                         int event_count_);
 
-        //  Internal state.
-        struct fds_set_t
-        {
-            fds_set_t ();
-            fds_set_t (const fds_set_t& other_);
-            fds_set_t& operator=(const fds_set_t& other_);
-            //  Convinient method to descriptor from all sets.
-            void remove_fd (const fd_t& fd_);
+    struct family_entry_t
+    {
+        family_entry_t ();
 
-            fd_set read;
-            fd_set write;
-            fd_set error;
-        };
+        fd_entries_t fd_entries;
+        fds_set_t fds_set;
+        bool retired;
+    };
 
-        struct fd_entry_t
-        {
-            fd_t fd;
-            zmq::i_poll_events* events;
-        };
-        typedef std::vector<fd_entry_t> fd_entries_t;
+    void select_family_entry (family_entry_t &family_entry_,
+                              int max_fd_,
+                              bool use_timeout_,
+                              struct timeval &tv_);
 
 #if defined ZMQ_HAVE_WINDOWS
-        struct family_entry_t
-        {
-            family_entry_t ();
-
-            fd_entries_t fd_entries;
-            fds_set_t fds_set;
-            bool retired;
-        };
-        typedef std::map<u_short, family_entry_t> family_entries_t;
-
-        struct wsa_events_t
-        {
-            wsa_events_t ();
-            ~wsa_events_t ();
-
-            //  read, write, error and readwrite
-            WSAEVENT events [4];
-        };
-#endif
+    typedef std::map<u_short, family_entry_t> family_entries_t;
 
-#if defined ZMQ_HAVE_WINDOWS
-        family_entries_t family_entries;
-        // See loop for details.
-        family_entries_t::iterator current_family_entry_it;
+    struct wsa_events_t
+    {
+        wsa_events_t ();
+        ~wsa_events_t ();
 
-        bool try_remove_fd_entry (family_entries_t::iterator family_entry_it,
-                                  zmq::fd_t &handle_);
-#else
-        fd_entries_t fd_entries;
-        fds_set_t fds_set;
-        fd_t maxfd;
-        bool retired;
-#endif
+        //  read, write, error and readwrite
+        WSAEVENT events [4];
+    };
 
-#if defined ZMQ_HAVE_WINDOWS
-        //  Socket's family or AF_UNSPEC on error.
-        static u_short get_fd_family (fd_t fd_);
+    family_entries_t family_entries;
+    // See loop for details.
+    family_entries_t::iterator current_family_entry_it;
+
+    bool try_remove_fd_entry (family_entries_t::iterator family_entry_it,
+                              zmq::fd_t &handle_);
+
+    static const size_t fd_family_cache_size = 8;
+    std::pair<fd_t, u_short> fd_family_cache [fd_family_cache_size];
+
+    u_short get_fd_family (fd_t fd_);
+
+    //  Socket's family or AF_UNSPEC on error.
+    static u_short determine_fd_family (fd_t fd_);
+#else
+    //  on non-Windows, we can treat all fds as one family
+    family_entry_t family_entry;
+    fd_t maxfd;
+    bool retired;
 #endif
-        //  Checks if an fd_entry_t is retired.
-        static bool is_retired_fd (const fd_entry_t &entry);
 
-        static fd_entries_t::iterator
-        find_fd_entry_by_handle (fd_entries_t &fd_entries, handle_t handle_);
+    //  Checks if an fd_entry_t is retired.
+    static bool is_retired_fd (const fd_entry_t &entry);
 
-        //  If true, thread is shutting down.
-        bool stopping;
+    static fd_entries_t::iterator
+    find_fd_entry_by_handle (fd_entries_t &fd_entries, handle_t handle_);
 
-        //  Handle of the physical thread doing the I/O work.
-        thread_t worker;
+    //  If true, thread is shutting down.
+    bool stopping;
 
-        select_t (const select_t&);
-        const select_t &operator = (const select_t&);
-    };
+    //  Handle of the physical thread doing the I/O work.
+    thread_t worker;
 
-    typedef select_t poller_t;
+    select_t (const select_t &);
+    const select_t &operator= (const select_t &);
+};
 
+typedef select_t poller_t;
 }
 
 #endif