14 files changed, 114 insertions, 90 deletions

diff --git a/auto_tests/tox_test.c b/auto_tests/tox_test.c
index 397c8acd..f578a5c9 100644
--- a/auto_tests/tox_test.c
+++ b/auto_tests/tox_test.c
@@ -443,7 +443,7 @@ START_TEST(test_few_clients)
 
     uint32_t to_compare = 974536;
     connected_t1 = 0;
-    tox_callback_self_connection_status(tox1, tox_connection_status, &to_compare);
+    tox_callback_self_connection_status(tox1, tox_connection_status);
     tox_callback_friend_request(tox2, accept_friend_request, &to_compare);
     uint8_t address[TOX_ADDRESS_SIZE];
     tox_self_get_address(tox2, address);
@@ -453,9 +453,9 @@ START_TEST(test_few_clients)
     uint8_t off = 1;
 
     while (1) {
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (tox_self_get_connection_status(tox1) && tox_self_get_connection_status(tox2)
                 && tox_self_get_connection_status(tox3)) {
@@ -487,9 +487,9 @@ START_TEST(test_few_clients)
 
     while (1) {
         messages_received = 0;
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (messages_received)
             break;
@@ -516,9 +516,9 @@ START_TEST(test_few_clients)
     off = 1;
 
     while (1) {
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (tox_self_get_connection_status(tox1) && tox_self_get_connection_status(tox2)
                 && tox_self_get_connection_status(tox3)) {
@@ -544,9 +544,9 @@ START_TEST(test_few_clients)
 
     while (1) {
         name_changes = 0;
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (name_changes)
             break;
@@ -565,9 +565,9 @@ START_TEST(test_few_clients)
 
     while (1) {
         status_m_changes = 0;
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (status_m_changes)
             break;
@@ -587,9 +587,9 @@ START_TEST(test_few_clients)
 
     while (1) {
         typing_changes = 0;
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
 
         if (typing_changes == 2)
@@ -605,9 +605,9 @@ START_TEST(test_few_clients)
 
     while (1) {
         typing_changes = 0;
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (typing_changes == 1)
             break;
@@ -632,9 +632,9 @@ START_TEST(test_few_clients)
 
     while (1) {
         custom_packet = 0;
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (custom_packet == 1)
             break;
@@ -654,9 +654,9 @@ START_TEST(test_few_clients)
 
     while (1) {
         custom_packet = 0;
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (custom_packet == 1)
             break;
@@ -690,9 +690,9 @@ START_TEST(test_few_clients)
     ck_assert_msg(gfierr == TOX_ERR_FILE_GET_OK, "wrong error");
 
     while (1) {
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (file_sending_done) {
             if (sendf_ok && file_recv && totalf_size == file_size && size_recv == file_size && sending_pos == size_recv
@@ -742,9 +742,9 @@ START_TEST(test_few_clients)
     m_send_reached = 0;
 
     while (1) {
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (file_sending_done) {
             if (sendf_ok && file_recv && m_send_reached && totalf_size == file_size && size_recv == max_sending
@@ -791,9 +791,9 @@ START_TEST(test_few_clients)
 
 
     while (1) {
-        tox_iterate(tox1);
-        tox_iterate(tox2);
-        tox_iterate(tox3);
+        tox_iterate(tox1, &to_compare);
+        tox_iterate(tox2, &to_compare);
+        tox_iterate(tox3, &to_compare);
 
         if (file_sending_done) {
             if (sendf_ok && file_recv && totalf_size == file_size && size_recv == file_size && sending_pos == size_recv
@@ -904,7 +904,7 @@ loop_top:
         }
 
         for (i = 0; i < NUM_TOXES; ++i) {
-            tox_iterate(toxes[i]);
+            tox_iterate(toxes[i], NULL);
         }
 
         c_sleep(50);
@@ -1002,7 +1002,7 @@ loop_top:
         }
 
         for (i = 0; i < NUM_TOXES_TCP; ++i) {
-            tox_iterate(toxes[i]);
+            tox_iterate(toxes[i], NULL);
         }
 
         c_sleep(50);
@@ -1098,7 +1098,7 @@ loop_top:
         }
 
         for (i = 0; i < NUM_TOXES_TCP; ++i) {
-            tox_iterate(toxes[i]);
+            tox_iterate(toxes[i], NULL);
         }
 
         c_sleep(30);
@@ -1206,7 +1206,7 @@ group_test_restart:
             break;
 
         for (i = 0; i < NUM_GROUP_TOX; ++i) {
-            tox_iterate(toxes[i]);
+            tox_iterate(toxes[i], NULL);
         }
 
         c_sleep(25);
@@ -1224,7 +1224,7 @@ group_test_restart:
 
     while (1) {
         for (i = 0; i < NUM_GROUP_TOX; ++i) {
-            tox_iterate(toxes[i]);
+            tox_iterate(toxes[i], NULL);
         }
 
         if (!invite_counter) {
@@ -1287,7 +1287,7 @@ group_test_restart:
 
     for (j = 0; j < 20; ++j) {
         for (i = 0; i < NUM_GROUP_TOX; ++i) {
-            tox_iterate(toxes[i]);
+            tox_iterate(toxes[i], NULL);
         }
 
         c_sleep(25);
@@ -1301,7 +1301,7 @@ group_test_restart:
 
         for (j = 0; j < 10; ++j) {
             for (i = 0; i < NUM_GROUP_TOX; ++i) {
-                tox_iterate(toxes[i]);
+                tox_iterate(toxes[i], NULL);
             }
 
             c_sleep(50);
diff --git a/auto_tests/toxav_basic_test.c b/auto_tests/toxav_basic_test.c
index 20432dca..f66846c5 100644
--- a/auto_tests/toxav_basic_test.c
+++ b/auto_tests/toxav_basic_test.c
@@ -124,9 +124,9 @@ void t_accept_friend_request_cb(Tox *m, const uint8_t *public_key, const uint8_t
  */
 int iterate_tox(Tox *bootstrap, Tox *Alice, Tox *Bob)
 {
-    tox_iterate(bootstrap);
-    tox_iterate(Alice);
-    tox_iterate(Bob);
+    tox_iterate(bootstrap, NULL);
+    tox_iterate(Alice, NULL);
+    tox_iterate(Bob, NULL);
 
     return MIN(tox_iteration_interval(Alice), tox_iteration_interval(Bob));
 }
diff --git a/auto_tests/toxav_many_test.c b/auto_tests/toxav_many_test.c
index ab496024..d626067c 100644
--- a/auto_tests/toxav_many_test.c
+++ b/auto_tests/toxav_many_test.c
@@ -248,11 +248,11 @@ START_TEST(test_AV_three_calls)
     uint8_t off = 1;
 
     while (1) {
-        tox_iterate(bootstrap);
-        tox_iterate(Alice);
-        tox_iterate(Bobs[0]);
-        tox_iterate(Bobs[1]);
-        tox_iterate(Bobs[2]);
+        tox_iterate(bootstrap, NULL);
+        tox_iterate(Alice, NULL);
+        tox_iterate(Bobs[0], NULL);
+        tox_iterate(Bobs[1], NULL);
+        tox_iterate(Bobs[2], NULL);
 
         if (tox_self_get_connection_status(bootstrap) &&
                 tox_self_get_connection_status(Alice) &&
@@ -313,10 +313,10 @@ START_TEST(test_AV_three_calls)
     time_t start_time = time(NULL);
 
     while (time(NULL) - start_time < 5) {
-        tox_iterate(Alice);
-        tox_iterate(Bobs[0]);
-        tox_iterate(Bobs[1]);
-        tox_iterate(Bobs[2]);
+        tox_iterate(Alice, NULL);
+        tox_iterate(Bobs[0], NULL);
+        tox_iterate(Bobs[1], NULL);
+        tox_iterate(Bobs[2], NULL);
         c_sleep(20);
     }
 
diff --git a/other/apidsl/README.md b/other/apidsl/README.md
index 3ba44678..99694dca 100644
--- a/other/apidsl/README.md
+++ b/other/apidsl/README.md
@@ -18,14 +18,16 @@ If you want to do it quickly and you don't have time for anything other than cop
 
 Command to run from ``toxcore`` directory (quick way, involves using curl):
 ```bash
-rm toxcore/tox.h && \
-( curl -X POST --data-binary @- https://apidsl.herokuapp.com/apidsl < ./other/apidsl/tox.in.h > ./toxcore/tox.h ) && \
-astyle --options=./other/astyle/astylerc ./toxcore/tox.h
-```
-
-When formatting will be complete, you should see output like:
-```
-Formatted  ./toxcore/tox.h
+# For tox.h:
+curl -X POST --data-binary @- https://apidsl.herokuapp.com/apidsl \
+  < other/apidsl/tox.in.h \
+  | astyle --options=other/astyle/astylerc \
+  > toxcore/tox.h
+# For toxav.h:
+curl -X POST --data-binary @- https://apidsl.herokuapp.com/apidsl \
+  < other/apidsl/toxav.in.h \
+  | astyle --options=other/astyle/astylerc \
+  > toxav/toxav.h
 ```
 
 You may want to make sure with ``git diff`` that changes made in ``tox.h`` reflect changes in ``tox.in.h``.
@@ -43,7 +45,7 @@ If you prefer to have more control over what is happening, there are steps below
 4. Use ``apidsl`` ``??``
 5. Parse generated ``tox.h`` with astyle, minimal command for it would be:
 ```bash
-astyle --options=./other/astyle/astylerc ./toxcore/tox.h
+astyle --options=other/astyle/astylerc toxcore/tox.h
 ```
 
 **Always pass output from ``apidsl`` through astyle.**
diff --git a/other/apidsl/tox.in.h b/other/apidsl/tox.in.h
index 577515b1..6e65ed1f 100644
--- a/other/apidsl/tox.in.h
+++ b/other/apidsl/tox.in.h
@@ -86,6 +86,19 @@ extern "C" {
  * callback will result in no callback being registered for that event. Only
  * one callback per event can be registered, so if a client needs multiple
  * event listeners, it needs to implement the dispatch functionality itself.
+ *
+ * The last argument to a callback is the user data pointer. It is passed from
+ * ${tox.iterate} to each callback in sequence.
+ *
+ * The user data pointer is never stored or dereferenced by any library code, so
+ * can be any pointer, including NULL. Callbacks must all operate on the same
+ * object type. In the apidsl code (tox.in.h), this is denoted with `any`. The
+ * `any` in ${tox.iterate} must be the same `any` as in all callbacks. In C,
+ * lacking parametric polymorphism, this is a pointer to void.
+ *
+ * Old style callbacks that are registered together with a user data pointer
+ * receive that pointer as argument when they are called. They can each have
+ * their own user data pointer of their own type.
  */
 
 /** \subsection threading Threading implications
@@ -713,7 +726,7 @@ inline namespace self {
    *
    * TODO: how long should a client wait before bootstrapping again?
    */
-  event connection_status {
+  event connection_status const {
     /**
      * @param connection_status Whether we are connected to the DHT.
      */
@@ -734,7 +747,7 @@ const uint32_t iteration_interval();
  * The main loop that needs to be run in intervals of $iteration_interval()
  * milliseconds.
  */
-void iterate();
+void iterate(any user_data);
 
 
 /*******************************************************************************
@@ -858,7 +871,6 @@ inline namespace self {
      *   If this parameter is NULL, the function has no effect.
      */
     get();
-
   }
 
 
@@ -1058,7 +1070,6 @@ namespace friend {
    */
   const bool exists(uint32_t friend_number);
 
-
 }
 
 inline namespace self {
diff --git a/testing/Messenger_test.c b/testing/Messenger_test.c
index 22e16c38..0c439a05 100644
--- a/testing/Messenger_test.c
+++ b/testing/Messenger_test.c
@@ -186,7 +186,7 @@ int main(int argc, char *argv[])
         printf("%s\n", name);
 
         m_send_message_generic(m, num, MESSAGE_NORMAL, (uint8_t *)"Test", 5, 0);
-        do_messenger(m);
+        do_messenger(m, NULL);
         c_sleep(30);
         FILE *file = fopen("Save.bak", "wb");
 
diff --git a/testing/irc_syncbot.c b/testing/irc_syncbot.c
index a4e2254a..f8d29bfc 100644
--- a/testing/irc_syncbot.c
+++ b/testing/irc_syncbot.c
@@ -349,7 +349,7 @@ int main(int argc, char *argv[])
             }
         }
 
-        tox_iterate(tox);
+        tox_iterate(tox, NULL);
         usleep(1000 * 50);
     }
 
diff --git a/testing/nTox.c b/testing/nTox.c
index 03f17da5..bbc48831 100644
--- a/testing/nTox.c
+++ b/testing/nTox.c
@@ -389,7 +389,7 @@ void line_eval(Tox *m, char *line)
 
             new_lines(numstring);
         } else if (inpt_command == 'd') {
-            tox_iterate(m);
+            tox_iterate(m, NULL);
         } else if (inpt_command == 'm') { //message command: /m friendnumber messsage
             char *posi[1];
             int num = strtoul(line + prompt_offset, posi, 0);
@@ -1354,7 +1354,7 @@ int main(int argc, char *argv[])
             }
         }
 
-        tox_iterate(m);
+        tox_iterate(m, NULL);
         do_refresh();
 
         int c = timeout_getch(m);
diff --git a/testing/tox_shell.c b/testing/tox_shell.c
index 0292222b..bda147b3 100644
--- a/testing/tox_shell.c
+++ b/testing/tox_shell.c
@@ -152,7 +152,7 @@ int main(int argc, char *argv[])
             tox_friend_send_message(tox, num, TOX_MESSAGE_TYPE_NORMAL, buf, ret, 0);
         }
 
-        tox_iterate(tox);
+        tox_iterate(tox, NULL);
         c_sleep(1);
     }
 
diff --git a/testing/tox_sync.c b/testing/tox_sync.c
index 738c2f2d..a90e343e 100644
--- a/testing/tox_sync.c
+++ b/testing/tox_sync.c
@@ -320,7 +320,7 @@ int main(int argc, char *argv[])
             }
         }
 
-        tox_iterate(tox);
+        tox_iterate(tox, NULL);
         c_sleep(1);
     }
 
diff --git a/toxcore/Messenger.c b/toxcore/Messenger.c
index 34296c24..3c60a818 100644
--- a/toxcore/Messenger.c
+++ b/toxcore/Messenger.c
@@ -816,10 +816,9 @@ void m_callback_connectionstatus(Messenger *m, void (*function)(Messenger *m, ui
     m->friend_connectionstatuschange_userdata = userdata;
 }
 
-void m_callback_core_connection(Messenger *m, void (*function)(Messenger *m, unsigned int, void *), void *userdata)
+void m_callback_core_connection(Messenger *m, void (*function)(Messenger *m, unsigned int, void *))
 {
     m->core_connection_change = function;
-    m->core_connection_change_userdata = userdata;
 }
 
 void m_callback_connectionstatus_internal_av(Messenger *m, void (*function)(Messenger *m, uint32_t, uint8_t, void *),
@@ -2232,13 +2231,13 @@ void do_friends(Messenger *m)
     }
 }
 
-static void connection_status_cb(Messenger *m)
+static void connection_status_cb(Messenger *m, void *userdata)
 {
     unsigned int conn_status = onion_connection_status(m->onion_c);
 
     if (conn_status != m->last_connection_status) {
         if (m->core_connection_change)
-            (*m->core_connection_change)(m, conn_status, m->core_connection_change_userdata);
+            (*m->core_connection_change)(m, conn_status, userdata);
 
         m->last_connection_status = conn_status;
     }
@@ -2282,7 +2281,7 @@ uint32_t messenger_run_interval(const Messenger *m)
 }
 
 /* The main loop that needs to be run at least 20 times per second. */
-void do_messenger(Messenger *m)
+void do_messenger(Messenger *m, void *userdata)
 {
     // Add the TCP relays, but only if this is the first time calling do_messenger
     if (m->has_added_relays == 0) {
@@ -2319,7 +2318,7 @@ void do_messenger(Messenger *m)
     do_onion_client(m->onion_c);
     do_friend_connections(m->fr_c);
     do_friends(m);
-    connection_status_cb(m);
+    connection_status_cb(m, userdata);
 
 #ifdef TOX_LOGGER
 
diff --git a/toxcore/Messenger.h b/toxcore/Messenger.h
index 26704dd1..dab792c8 100644
--- a/toxcore/Messenger.h
+++ b/toxcore/Messenger.h
@@ -277,7 +277,6 @@ struct Messenger {
     void *lossless_packethandler_userdata;
 
     void (*core_connection_change)(struct Messenger *m, unsigned int, void *);
-    void *core_connection_change_userdata;
     unsigned int last_connection_status;
 
     Messenger_Options options;
@@ -540,7 +539,7 @@ void m_callback_connectionstatus_internal_av(Messenger *m, void (*function)(Mess
 /* Set the callback for typing changes.
  *  Function(unsigned int connection_status (0 = not connected, 1 = TCP only, 2 = UDP + TCP))
  */
-void m_callback_core_connection(Messenger *m, void (*function)(Messenger *m, unsigned int, void *), void *userdata);
+void m_callback_core_connection(Messenger *m, void (*function)(Messenger *m, unsigned int, void *));
 
 /**********GROUP CHATS************/
 
@@ -747,7 +746,7 @@ Messenger *new_messenger(Messenger_Options *options, unsigned int *error);
 void kill_messenger(Messenger *m);
 
 /* The main loop that needs to be run at least 20 times per second. */
-void do_messenger(Messenger *m);
+void do_messenger(Messenger *m, void *userdata);
 
 /* Return the time in milliseconds before do_messenger() should be called again
  * for optimal performance.
diff --git a/toxcore/tox.c b/toxcore/tox.c
index b642db75..4708bc97 100644
--- a/toxcore/tox.c
+++ b/toxcore/tox.c
@@ -390,10 +390,10 @@ TOX_CONNECTION tox_self_get_connection_status(const Tox *tox)
 }
 
 
-void tox_callback_self_connection_status(Tox *tox, tox_self_connection_status_cb *function, void *user_data)
+void tox_callback_self_connection_status(Tox *tox, tox_self_connection_status_cb *function)
 {
     Messenger *m = tox;
-    m_callback_core_connection(m, function, user_data);
+    m_callback_core_connection(m, function);
 }
 
 uint32_t tox_iteration_interval(const Tox *tox)
@@ -402,10 +402,10 @@ uint32_t tox_iteration_interval(const Tox *tox)
     return messenger_run_interval(m);
 }
 
-void tox_iterate(Tox *tox)
+void tox_iterate(Tox *tox, void *userdata)
 {
     Messenger *m = tox;
-    do_messenger(m);
+    do_messenger(m, userdata);
     do_groupchats(m->group_chat_object);
 }
 
diff --git a/toxcore/tox.h b/toxcore/tox.h
index 1655d9c1..ca6869e4 100644
--- a/toxcore/tox.h
+++ b/toxcore/tox.h
@@ -84,6 +84,19 @@ extern "C" {
  * callback will result in no callback being registered for that event. Only
  * one callback per event can be registered, so if a client needs multiple
  * event listeners, it needs to implement the dispatch functionality itself.
+ *
+ * The last argument to a callback is the user data pointer. It is passed from
+ * tox_iterate to each callback in sequence.
+ *
+ * The user data pointer is never stored or dereferenced by any library code, so
+ * can be any pointer, including NULL. Callbacks must all operate on the same
+ * object type. In the apidsl code (tox.in.h), this is denoted with `any`. The
+ * `any` in tox_iterate must be the same `any` as in all callbacks. In C,
+ * lacking parametric polymorphism, this is a pointer to void.
+ *
+ * Old style callbacks that are registered together with a user data pointer
+ * receive that pointer as argument when they are called. They can each have
+ * their own user data pointer of their own type.
  */
 /** \subsection threading Threading implications
  *
@@ -776,7 +789,7 @@ typedef void tox_self_connection_status_cb(Tox *tox, TOX_CONNECTION connection_s
  *
  * TODO: how long should a client wait before bootstrapping again?
  */
-void tox_callback_self_connection_status(Tox *tox, tox_self_connection_status_cb *callback, void *user_data);
+void tox_callback_self_connection_status(Tox *tox, tox_self_connection_status_cb *callback);
 
 /**
  * Return the time in milliseconds before tox_iterate() should be called again
@@ -788,7 +801,7 @@ uint32_t tox_iteration_interval(const Tox *tox);
  * The main loop that needs to be run in intervals of tox_iteration_interval()
  * milliseconds.
  */
-void tox_iterate(Tox *tox);
+void tox_iterate(Tox *tox, void *user_data);
 
 
 /*******************************************************************************