2 files changed, 148 insertions, 9 deletions

diff --git a/toxcore/group.c b/toxcore/group.c
index da56c572..6f0cfef3 100644
--- a/toxcore/group.c
+++ b/toxcore/group.c
@@ -431,6 +431,9 @@ static int addpeer(Group_Chats *g_c, int groupnumber, const uint8_t *real_pk, co
         g_c->peer_namelistchange(g_c->m, groupnumber, g->numpeers - 1, CHAT_CHANGE_PEER_ADD,
                                  g_c->group_namelistchange_userdata);
 
+    if (g_c->peer_on_join)
+        g_c->peer_on_join(g->object, groupnumber, g->numpeers - 1);
+
     return (g->numpeers - 1);
 }
 
@@ -460,25 +463,29 @@ static int delpeer(Group_Chats *g_c, int groupnumber, int peer_index)
     Group_Peer *temp;
     --g->numpeers;
 
+    void *peer_object = g->group[peer_index].object;
+
     if (g->numpeers == 0) {
         free(g->group);
         g->group = NULL;
-        return 0;
-    }
-
-    if (g->numpeers != (uint32_t)peer_index)
-        memcpy(&g->group[peer_index], &g->group[g->numpeers], sizeof(Group_Peer));
+    } else {
+        if (g->numpeers != (uint32_t)peer_index)
+            memcpy(&g->group[peer_index], &g->group[g->numpeers], sizeof(Group_Peer));
 
-    temp = realloc(g->group, sizeof(Group_Peer) * (g->numpeers));
+        temp = realloc(g->group, sizeof(Group_Peer) * (g->numpeers));
 
-    if (temp == NULL)
-        return -1;
+        if (temp == NULL)
+            return -1;
 
-    g->group = temp;
+        g->group = temp;
+    }
 
     if (g_c->peer_namelistchange)
         g_c->peer_namelistchange(g_c->m, groupnumber, peer_index, CHAT_CHANGE_PEER_DEL, g_c->group_namelistchange_userdata);
 
+    if (g_c->peer_on_leave)
+        g_c->peer_on_leave(g->object, groupnumber, peer_index, peer_object);
+
     return 0;
 }
 
@@ -950,6 +957,24 @@ void g_callback_group_namelistchange(Group_Chats *g_c, void (*function)(Messenge
     g_c->group_namelistchange_userdata = userdata;
 }
 
+/* Set a function to be called when a new peer joins a group chat.
+ *
+ * Function(void *group object (set with group_set_object), int groupnumber, int friendgroupnumber)
+ */
+void callback_groupchat_peer_new(const Group_Chats *g_c, void (*function)(void *, int, int))
+{
+    g_c->peer_on_join = function;
+}
+
+/* Set a function to be called when a peer leaves a group chat.
+ *
+ * Function(void *group object (set with group_set_object), int groupnumber, int friendgroupnumber, void *group peer object (set with group_peer_set_object))
+ */
+void callback_groupchat_peer_delete(const Group_Chats *g_c, void (*function)(void *, int, int, void *))
+{
+    g_c->peer_on_leave = function;
+}
+
 static unsigned int send_message_group(const Group_Chats *g_c, int groupnumber, uint8_t message_id, const uint8_t *data,
                                        uint16_t len);
 
@@ -1785,6 +1810,74 @@ static int handle_lossy(void *object, int friendcon_id, const uint8_t *data, uin
     return 0;
 }
 
+/* Set the object that is tied to the group chat.
+ *
+ * return 0 on success.
+ * return -1 on failure
+ */
+int group_set_object(const Group_Chats *g_c, int groupnumber, void *object)
+{
+    Group_c *g = get_group_c(g_c, groupnumber);
+
+    if (!g)
+        return -1;
+
+    g->object = object;
+    return 0;
+}
+
+/* Set the object that is tied to the group peer.
+ *
+ * return 0 on success.
+ * return -1 on failure
+ */
+int group_peer_set_object(const Group_Chats *g_c, int groupnumber, int peernumber, void *object)
+{
+    Group_c *g = get_group_c(g_c, groupnumber);
+
+    if (!g)
+        return -1;
+
+    if ((uint32_t)peernumber >= g->numpeers)
+        return -1;
+
+    g->group[peernumber].object = object;
+    return 0;
+}
+
+/* Return the object tide to the group chat previously set by group_set_object.
+ *
+ * return NULL on failure.
+ * return object on success.
+ */
+void *group_get_object(const Group_Chats *g_c, int groupnumber)
+{
+    Group_c *g = get_group_c(g_c, groupnumber);
+
+    if (!g)
+        return NULL;
+
+    return g->object;
+}
+
+/* Return the object tide to the group chat peer previously set by group_peer_set_object.
+ *
+ * return NULL on failure.
+ * return object on success.
+ */
+void *group_peer_get_object(const Group_Chats *g_c, int groupnumber, int peernumber)
+{
+    Group_c *g = get_group_c(g_c, groupnumber);
+
+    if (!g)
+        return NULL;
+
+    if ((uint32_t)peernumber >= g->numpeers)
+        return NULL;
+
+    return g->group[peernumber].object;
+}
+
 /* Interval in seconds to send ping messages */
 #define GROUP_PING_INTERVAL 30
 
diff --git a/toxcore/group.h b/toxcore/group.h
index e307bec9..41c7078e 100644
--- a/toxcore/group.h
+++ b/toxcore/group.h
@@ -49,6 +49,8 @@ typedef struct {
 
     uint8_t  recv_lossy[MAX_LOSSY_COUNT];
     uint16_t bottom_lossy_number, top_lossy_number;
+
+    void *object;
 } Group_Peer;
 
 #define DESIRED_CLOSE_CONNECTIONS 4
@@ -91,6 +93,8 @@ typedef struct {
     uint64_t last_sent_ping;
 
     int number_joined; /* friendcon_id of person that invited us to the chat. (-1 means none) */
+
+    void *object;
 } Group_c;
 
 typedef struct {
@@ -109,6 +113,8 @@ typedef struct {
     void (*peer_namelistchange)(Messenger *m, int, int, uint8_t, void *);
     void *group_namelistchange_userdata;
 
+    void (*peer_on_join)(void *, int, int);
+    void (*peer_on_leave)(void *, int, int, void *);
     struct {
         int (*function)(Messenger *m, int, int, const uint8_t *, uint16_t, void *);
         void *userdata;
@@ -252,6 +258,46 @@ uint32_t copy_chatlist(Group_Chats *g_c, int32_t *out_list, uint32_t list_size);
  */
 void send_name_all_groups(Group_Chats *g_c);
 
+/* Set the object that is tied to the group chat.
+ *
+ * return 0 on success.
+ * return -1 on failure
+ */
+int group_set_object(const Group_Chats *g_c, int groupnumber, void *object);
+
+/* Set the object that is tied to the group peer.
+ *
+ * return 0 on success.
+ * return -1 on failure
+ */
+int group_peer_set_object(const Group_Chats *g_c, int groupnumber, int peernumber, void *object);
+
+/* Return the object tide to the group chat previously set by group_set_object.
+ *
+ * return NULL on failure.
+ * return object on success.
+ */
+void *group_get_object(const Group_Chats *g_c, int groupnumber);
+
+/* Return the object tide to the group chat peer previously set by group_peer_set_object.
+ *
+ * return NULL on failure.
+ * return object on success.
+ */
+void *group_peer_get_object(const Group_Chats *g_c, int groupnumber, int peernumber);
+
+/* Set a function to be called when a new peer joins a group chat.
+ *
+ * Function(void *group object (set with group_set_object), int groupnumber, int friendgroupnumber)
+ */
+void callback_groupchat_peer_new(const Group_Chats *g_c, void (*function)(void *, int, int));
+
+/* Set a function to be called when a peer leaves a group chat.
+ *
+ * Function(void *group object (set with group_set_object), int groupnumber, int friendgroupnumber, void *group peer object (set with group_peer_set_object))
+ */
+void callback_groupchat_peer_delete(const Group_Chats *g_c, void (*function)(void *, int, int, void *));
+
 /* Create new groupchat instance. */
 Group_Chats *new_groupchats(Messenger *m);