From fab723b9bcd1bbfed4e4b39916ae14cfeb59c0e4 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 31 Jan 2019 19:30:40 +0530
Subject: [PATCH] Manage timer callback reference counts

---
 kitty/child-monitor.c |  9 ++++++++-
 kitty/timers.c        | 32 +++++++++++++++++++++-----------
 kitty/timers.h        |  5 ++++-
 3 files changed, 33 insertions(+), 13 deletions(-)

diff --git a/kitty/child-monitor.c b/kitty/child-monitor.c
index 103d16e02..04ebfcb0b 100644
--- a/kitty/child-monitor.c
+++ b/kitty/child-monitor.c
@@ -747,13 +747,19 @@ python_timer_callback(id_type timer_id, void *data) {
     else Py_DECREF(ret);
 }
 
+static void
+python_timer_cleanup(id_type timer_id UNUSED, void *data) {
+    if (data) Py_DECREF((PyObject*)data);
+}
+
 static PyObject*
 add_python_timer(PyObject *self UNUSED, PyObject *args) {
     PyObject *callback;
     double interval;
     const char *name;
     if (!PyArg_ParseTuple(args, "sOd", &name, &callback, &interval)) return NULL;
-    unsigned long long timer_id = add_timer(&main_event_loop, name, interval, 1, python_timer_callback, callback);
+    unsigned long long timer_id = add_timer(&main_event_loop, name, interval, 1, python_timer_callback, callback, python_timer_cleanup);
+    Py_INCREF(callback);
     return Py_BuildValue("K", timer_id);
 }
 
@@ -860,6 +866,7 @@ main_loop(ChildMonitor *self, PyObject *a UNUSED) {
         }
         has_open_windows = process_pending_closes(self);
     }
+    remove_all_timers(&main_event_loop);
     if (PyErr_Occurred()) return NULL;
     Py_RETURN_NONE;
 }
diff --git a/kitty/timers.c b/kitty/timers.c
index 1b8e646a6..16f988b1a 100644
--- a/kitty/timers.c
+++ b/kitty/timers.c
@@ -22,7 +22,7 @@ update_timers(EventLoopData *eld) {
 }
 
 id_type
-add_timer(EventLoopData *eld, const char *name, double interval, int enabled, timer_callback_func cb, void *cb_data) {
+add_timer(EventLoopData *eld, const char *name, double interval, int enabled, timer_callback_func cb, void *cb_data, timer_cleanup_func cleanup) {
     if (eld->timers_count >= sizeof(eld->timers)/sizeof(eld->timers[0])) {
         fprintf(stderr, "Too many timers added\n");
         return 0;
@@ -33,24 +33,34 @@ add_timer(EventLoopData *eld, const char *name, double interval, int enabled, ti
     t->trigger_at = enabled ? monotonic() + interval : DBL_MAX;
     t->callback = cb;
     t->callback_data = cb_data;
+    t->cleanup = cleanup;
     t->id = ++timer_counter;
     update_timers(eld);
     return t->id;
 }
 
-#define removeX(which, item_id, update_func) {\
-    for (nfds_t i = 0; i < eld->which##_count; i++) { \
-        if (eld->which[i].id == item_id) { \
-            eld->which##_count--; \
-            if (i < eld->which##_count) { \
-                memmove(eld->which + i, eld->which + i + 1, sizeof(eld->which[0]) * (eld->which##_count - i)); \
-            } \
-            update_func(eld); break; \
-}}}
 
 void
 remove_timer(EventLoopData *eld, id_type timer_id) {
-    removeX(timers, timer_id, update_timers);
+    for (nfds_t i = 0; i < eld->timers_count; i++) {
+        if (eld->timers[i].id == timer_id) {
+            if (eld->timers[i].cleanup) eld->timers[i].cleanup(timer_id, eld->timers[i].callback_data);
+            eld->timers_count--;
+            if (i < eld->timers_count) {
+                memmove(eld->timers + i, eld->timers + i + 1, sizeof(eld->timers[0]) * (eld->timers_count - i));
+            }
+            update_timers(eld);
+            break;
+        }
+    }
+}
+
+void
+remove_all_timers(EventLoopData *eld) {
+    while (eld->timers_count) {
+        eld->timers_count--;
+        if (eld->timers[eld->timers_count].cleanup) eld->timers[eld->timers_count].cleanup(eld->timers[eld->timers_count].id, eld->timers[eld->timers_count].callback_data);
+    }
 }
 
 void
diff --git a/kitty/timers.h b/kitty/timers.h
index cd47cdb9e..b0260a538 100644
--- a/kitty/timers.h
+++ b/kitty/timers.h
@@ -9,11 +9,13 @@
 #include "data-types.h"
 
 typedef void(*timer_callback_func)(id_type, void*);
+typedef void(*timer_cleanup_func)(id_type, void*);
 
 typedef struct {
     id_type id;
     double interval, trigger_at;
     timer_callback_func callback;
+    timer_cleanup_func cleanup;
     void *callback_data;
     const char *name;
 } Timer;
@@ -26,8 +28,9 @@ typedef struct {
 
 
 double prepare_for_poll(EventLoopData *eld, double timeout);
-id_type add_timer(EventLoopData *eld, const char *name, double interval, int enabled, timer_callback_func cb, void *cb_data);
+id_type add_timer(EventLoopData *eld, const char *name, double interval, int enabled, timer_callback_func cb, void *cb_data, timer_cleanup_func cleanup);
 void remove_timer(EventLoopData *eld, id_type timer_id);
+void remove_all_timers(EventLoopData *eld);
 void toggle_time(EventLoopData *eld, id_type timer_id, int enabled);
 void change_timer_interval(EventLoopData *eld, id_type timer_id, double interval);
 unsigned int dispatch_timers(EventLoopData *eld);