events: Refactor event_poll to use stack-allocated timer handles

1 files changed, 28 insertions, 15 deletions

diff --git a/src/nvim/os/event.c b/src/nvim/os/event.c
index 2ebf28f436..40ddf7097e 100644
--- a/src/nvim/os/event.c
+++ b/src/nvim/os/event.c
@@ -21,12 +21,16 @@
 #define _destroy_event(x)  // do nothing
 KLIST_INIT(Event, Event, _destroy_event)
 
+typedef struct {
+  bool timed_out;
+  int32_t ms;
+  uv_timer_t *timer;
+} TimerData;
+
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "os/event.c.generated.h"
 #endif
 static klist_t(Event) *event_queue;
-static uv_timer_t timer;
-static uv_prepare_t timer_prepare;
 
 void event_init()
 {
@@ -44,9 +48,6 @@ void event_init()
   channel_init();
   // Servers
   server_init();
-  uv_timer_init(uv_default_loop(), &timer);
-  // This prepare handle that actually starts the timer
-  uv_prepare_init(uv_default_loop(), &timer_prepare);
 }
 
 void event_teardown()
@@ -59,7 +60,6 @@ void event_teardown()
 // Wait for some event
 bool event_poll(int32_t ms)
 {
-  bool timed_out;
   uv_run_mode run_mode = UV_RUN_ONCE;
 
   if (input_ready()) {
@@ -68,14 +68,20 @@ bool event_poll(int32_t ms)
   }
 
   input_start();
-  timed_out = false;
+
+  uv_timer_t timer;
+  uv_prepare_t timer_prepare;
+  TimerData timer_data = {.ms = ms, .timed_out = false, .timer = &timer};
 
   if (ms > 0) {
+    uv_timer_init(uv_default_loop(), &timer);
+    // This prepare handle that actually starts the timer
+    uv_prepare_init(uv_default_loop(), &timer_prepare);
     // Timeout passed as argument to the timer
-    timer.data = &timed_out;
+    timer.data = &timer_data;
     // We only start the timer after the loop is running, for that we
     // use a prepare handle(pass the interval as data to it)
-    timer_prepare.data = &ms;
+    timer_prepare.data = &timer_data;
     uv_prepare_start(&timer_prepare, timer_prepare_cb);
   } else if (ms == 0) {
     // For ms == 0, we need to do a non-blocking event poll by
@@ -92,13 +98,17 @@ bool event_poll(int32_t ms)
       !input_ready() &&   // we have no input
       kl_empty(event_queue) &&   // no events are waiting to be processed
       run_mode != UV_RUN_NOWAIT &&   // ms != 0
-      !timed_out);  // we didn't get a timeout
+      !timer_data.timed_out);  // we didn't get a timeout
 
   input_stop();
 
   if (ms > 0) {
-    // Stop the timer
-    uv_timer_stop(&timer);
+    // Ensure the timer-related handles are closed and run the event loop
+    // once more to let libuv perform it's cleanup
+    uv_close((uv_handle_t *)&timer, NULL);
+    uv_close((uv_handle_t *)&timer_prepare, NULL);
+    uv_run(uv_default_loop(), UV_RUN_NOWAIT);
+    event_process(false);
   }
 
   return input_ready() || event_is_pending();
@@ -140,11 +150,14 @@ void event_process()
 // Set a flag in the `event_poll` loop for signaling of a timeout
 static void timer_cb(uv_timer_t *handle)
 {
-  *((bool *)handle->data) = true;
+  TimerData *data = handle->data;
+  data->timed_out = true;
 }
 
 static void timer_prepare_cb(uv_prepare_t *handle)
 {
-  uv_timer_start(&timer, timer_cb, *(uint32_t *)timer_prepare.data, 0);
-  uv_prepare_stop(&timer_prepare);
+  TimerData *data = handle->data;
+  assert(data->ms > 0);
+  uv_timer_start(data->timer, timer_cb, (uint32_t)data->ms, 0);
+  uv_prepare_stop(handle);
 }