Amp is the one place where we generate a per-sample vector for automation playback...

[ardour.git] / libs / pbd / pbd / event_loop.h

diff --git a/libs/pbd/pbd/event_loop.h b/libs/pbd/pbd/event_loop.h
index be98fcd852a771a5d43b5b19ae44a05ae1ed05e4..5f1f1344dd4d2e091e15998893ef7c77d9991289 100644 (file)
--- a/libs/pbd/pbd/event_loop.h
+++ b/libs/pbd/pbd/event_loop.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2009 Paul Davis 
+    Copyright (C) 2009 Paul Davis
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -20,29 +20,123 @@
 #ifndef __pbd_event_loop_h__
 #define __pbd_event_loop_h__
 
+#include <string>
+#include <vector>
+#include <map>
 #include <boost/function.hpp>
 #include <boost/bind.hpp> /* we don't need this here, but anything calling call_slot() probably will, so this is convenient */
-#include <glibmm/thread.h>
+#include <stdint.h>
+#include <pthread.h>
+#include <glibmm/threads.h>
+
+#include "pbd/libpbd_visibility.h"
 
 namespace PBD
 {
 
-class EventLoop 
+/** An EventLoop is as basic abstraction designed to be used with any "user
+ * interface" (not necessarily graphical) that needs to wait on
+ * events/requests and dispatch/process them as they arrive.
+ *
+ * This is a very basic class that doesn't by itself provide an actual
+ * event loop or thread. See BaseUI for the "real" object to be used
+ * when something like this is needed (it inherits from EventLoop).
+ */
+
+class LIBPBD_API EventLoop
 {
-  public:
-       EventLoop() {}
-       virtual ~EventLoop() {}
+public:
+       EventLoop (std::string const&);
+       virtual ~EventLoop();
+
+       enum RequestType {
+               range_guarantee = ~0
+       };
+
+       struct BaseRequestObject;
+
+       struct InvalidationRecord {
+               std::list<BaseRequestObject*> requests;
+               PBD::EventLoop* event_loop;
+               gint _valid;
+               gint _ref;
+               const char* file;
+               int line;
+
+               InvalidationRecord() : event_loop (0), _valid (1), _ref (0) {}
+               void invalidate () { g_atomic_int_set (&_valid, 0); }
+               bool valid () { return g_atomic_int_get (&_valid) == 1; }
+
+               void ref ()    { g_atomic_int_inc (&_ref); }
+               void unref ()  { g_atomic_int_dec_and_test (&_ref); }
+               bool in_use () { return g_atomic_int_get (&_ref) > 0; }
+               int  use_count () { return g_atomic_int_get (&_ref); }
+       };
+
+       static void* invalidate_request (void* data);
+
+       struct BaseRequestObject {
+               RequestType             type;
+               InvalidationRecord*     invalidation;
+               boost::function<void()> the_slot;
+
+               BaseRequestObject() : invalidation (0) {}
+               ~BaseRequestObject() {
+                       if (invalidation) {
+                               invalidation->unref ();
+                       }
+               }
+       };
 
-       virtual void call_slot (const boost::function<void()>&) = 0;
+       virtual void call_slot (InvalidationRecord*, const boost::function<void()>&) = 0;
+       virtual Glib::Threads::Mutex& slot_invalidation_mutex() = 0;
+
+       std::string event_loop_name() const { return _name; }
 
        static EventLoop* get_event_loop_for_thread();
        static void set_event_loop_for_thread (EventLoop* ui);
 
-  private:
-       static Glib::StaticPrivate<EventLoop> thread_event_loop;
+       struct ThreadBufferMapping {
+               pthread_t emitting_thread;
+               std::string target_thread_name;
+               void* request_buffer;
+       };
+
+       static std::vector<ThreadBufferMapping> get_request_buffers_for_target_thread (const std::string&);
+
+       static void register_request_buffer_factory (const std::string& target_thread_name, void* (*factory) (uint32_t));
+       static void pre_register (const std::string& emitting_thread_name, uint32_t num_requests);
+       static void remove_request_buffer_from_map (void* ptr);
+
+       std::list<InvalidationRecord*> trash;
+
+private:
+       static Glib::Threads::Private<EventLoop> thread_event_loop;
+       std::string _name;
 
+       typedef std::map<std::string,ThreadBufferMapping> ThreadRequestBufferList;
+       static ThreadRequestBufferList thread_buffer_requests;
+       static Glib::Threads::RWLock   thread_buffer_requests_lock;
+
+       struct RequestBufferSupplier {
+
+               /* @param name : name of object/entity that will/may accept
+                * requests from other threads, via a request buffer.
+                */
+               std::string name;
+
+               /* @param factory : a function that can be called (with an
+                * argument specifying the @param number_of_requests) to create and
+                * return a request buffer for communicating with @param name)
+                */
+               void* (*factory)(uint32_t nunber_of_requests);
+       };
+       typedef std::vector<RequestBufferSupplier> RequestBufferSuppliers;
+       static RequestBufferSuppliers request_buffer_suppliers;
 };
 
 }
 
+#define MISSING_INVALIDATOR 0 // used to mark places where we fail to provide an invalidator
+
 #endif /* __pbd_event_loop_h__ */