From 7338b8f22d06c04b3fe7b96952ac5591838b2797 Mon Sep 17 00:00:00 2001
From: Stephen Sinclair <radarsat1@gmail.com>
Date: Thu, 2 Mar 2017 15:40:28 -0300
Subject: [PATCH] C api: track CallbackProxyUserData and delete it

Fixes #104.
---
 rtmidi_c.cpp | 39 +++++++++++++++++++++++----------------
 rtmidi_c.h   |  1 +
 2 files changed, 24 insertions(+), 16 deletions(-)

diff --git a/rtmidi_c.cpp b/rtmidi_c.cpp
index 5148a718..3b6577c3 100644
--- a/rtmidi_c.cpp
+++ b/rtmidi_c.cpp
@@ -3,6 +3,17 @@
 #include "rtmidi_c.h"
 #include "RtMidi.h"
 
+class CallbackProxyUserData
+{
+  public:
+	CallbackProxyUserData (RtMidiCCallback cCallback, void *userData)
+		: c_callback (cCallback), user_data (userData)
+	{
+	}
+	RtMidiCCallback c_callback;
+	void *user_data;
+};
+
 /* misc */
 int rtmidi_sizeof_rtmidi_api ()
 {
@@ -133,11 +144,13 @@ RtMidiInPtr rtmidi_in_create (enum RtMidiApi api, const char *clientName, unsign
         RtMidiIn* rIn = new RtMidiIn ((RtMidi::Api) api, name, queueSizeLimit);
         
         wrp->ptr = (void*) rIn;
+        wrp->data = 0;
         wrp->ok  = true;
         wrp->msg = "";
 
     } catch (const RtMidiError & err) {
-        wrp->ptr = 0; 
+        wrp->ptr = 0;
+        wrp->data = 0;
         wrp->ok  = false;
         wrp->msg = err.what ();
     }
@@ -147,6 +160,8 @@ RtMidiInPtr rtmidi_in_create (enum RtMidiApi api, const char *clientName, unsign
 
 void rtmidi_in_free (RtMidiInPtr device)
 {
+    if (device->data)
+      delete (CallbackProxyUserData*) device->data;
     delete (RtMidiIn*) device->ptr;
     delete device;
 }
@@ -164,17 +179,7 @@ enum RtMidiApi rtmidi_in_get_current_api (RtMidiPtr device)
     }
 }
 
-class CallbackProxyUserData
-{
-  public:
-	CallbackProxyUserData (RtMidiCCallback cCallback, void *userData)
-		: c_callback (cCallback), user_data (userData)
-	{
-	}
-	RtMidiCCallback c_callback;
-	void *user_data;
-};
-
+static
 void callback_proxy (double timeStamp, std::vector<unsigned char> *message, void *userData)
 {
 	CallbackProxyUserData* data = reinterpret_cast<CallbackProxyUserData*> (userData);
@@ -183,13 +188,14 @@ void callback_proxy (double timeStamp, std::vector<unsigned char> *message, void
 
 void rtmidi_in_set_callback (RtMidiInPtr device, RtMidiCCallback callback, void *userData)
 {
+    device->data = (void*) new CallbackProxyUserData (callback, userData);
     try {
-        void *data = (void *) new CallbackProxyUserData (callback, userData);
-        ((RtMidiIn*) device->ptr)->setCallback (callback_proxy, data);
-    
+        ((RtMidiIn*) device->ptr)->setCallback (callback_proxy, device->data);
     } catch (const RtMidiError & err) {
         device->ok  = false;
         device->msg = err.what ();
+        delete (CallbackProxyUserData*) device->data;
+        device->data = 0;
     }
 }
 
@@ -197,7 +203,8 @@ void rtmidi_in_cancel_callback (RtMidiInPtr device)
 {
     try {
         ((RtMidiIn*) device->ptr)->cancelCallback ();
-
+        delete (CallbackProxyUserData*) device->data;
+        device->data = 0;
     } catch (const RtMidiError & err) {
         device->ok  = false;
         device->msg = err.what ();
diff --git a/rtmidi_c.h b/rtmidi_c.h
index 1434763f..01b1bfc5 100644
--- a/rtmidi_c.h
+++ b/rtmidi_c.h
@@ -15,6 +15,7 @@ extern "C" {
 
 struct RtMidiWrapper {
     void* ptr;
+    void* data;
     bool  ok;
     const char* msg;
 };