event: Ensure the event loop has been cleaned up in event_teardown

- Add input_teardown/signal_teardown to take care of closing signal/stdin
  handles.
- Call those functions in event_teardown, and ensure there are no active handles
  by entering an infinite loop when there are unclosed handles(think of this as
  an assertion that can't go unoticed on travis).
- Move event_teardown call to the end of mch_exit. That is required because
  event_poll may still be called in that function.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/nvim/os/input.c b/src/nvim/os/input.c
index d948a48b64..3ebfb3f12b 100644
--- a/src/nvim/os/input.c
+++ b/src/nvim/os/input.c
@@ -52,6 +52,15 @@ void input_init(void)
   rstream_set_file(read_stream, read_cmd_fd);
 }
 
+void input_teardown(void)
+{
+  if (embedded_mode) {
+    return;
+  }
+
+  rstream_free(read_stream);
+}
+
 // Listen for input
 void input_start(void)
 {