api/nvim_get_mode: Use child-queue instead of "priority".

src/nvim/api/vim.c

@@ -11,7 +11,6 @@
 
 #include "nvim/api/vim.h"
 #include "nvim/ascii.h"
-#include "nvim/log.h"
 #include "nvim/api/private/helpers.h"
 #include "nvim/api/private/defs.h"
 #include "nvim/api/buffer.h"

src/nvim/event/multiqueue.c

@@ -55,7 +55,6 @@
 
 #include "nvim/event/multiqueue.h"
 #include "nvim/memory.h"
-#include "nvim/log.h"
 #include "nvim/os/time.h"
 
 typedef struct multiqueue_item MultiQueueItem;

src/nvim/msgpack_rpc/channel.c

@@ -28,7 +28,6 @@
 #include "nvim/map.h"
 #include "nvim/log.h"
 #include "nvim/misc1.h"
-#include "nvim/state.h"
 #include "nvim/lib/kvec.h"
 #include "nvim/os/input.h"
 
@@ -91,6 +90,7 @@ static msgpack_sbuffer out_buffer;
 /// Initializes the module
 void channel_init(void)
 {
+  ch_before_blocking_events = multiqueue_new_child(main_loop.events);
   channels = pmap_new(uint64_t)();
   event_strings = pmap_new(cstr_t)();
   msgpack_sbuffer_init(&out_buffer);
@@ -446,9 +446,8 @@ static void handle_request(Channel *channel, msgpack_object *request)
       && !strncmp("nvim_get_mode", method->via.bin.ptr, method->via.bin.size);
 
     if (is_get_mode && !input_blocking()) {
-      // Schedule on the main loop with special priority. #6247
-      Event ev = event_create(kEvPriorityAsync, on_request_event, 1, evdata);
-      multiqueue_put_event(channel->events, ev);
+      // Defer the event to a special queue used by os/input.c. #6247
+      multiqueue_put(ch_before_blocking_events, on_request_event, 1, evdata);
     } else {
       // Invoke immediately.
       on_request_event((void **)&evdata);

src/nvim/msgpack_rpc/channel.h

@@ -11,6 +11,11 @@
 
 #define METHOD_MAXLEN 512
 
+/// HACK: os/input.c drains this queue immediately before blocking for input.
+///       Events on this queue are async-safe, but they need the resolved state
+///       of os_inchar(), so they are processed "just-in-time".
+MultiQueue *ch_before_blocking_events;
+
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "msgpack_rpc/channel.h.generated.h"
 #endif

src/nvim/normal.c

@@ -14,7 +14,6 @@
 #include <stdlib.h>
 
 #include "nvim/vim.h"
-#include "nvim/log.h"
 #include "nvim/ascii.h"
 #include "nvim/normal.h"
 #include "nvim/buffer.h"

src/nvim/os/input.c

@@ -23,7 +23,7 @@
 #include "nvim/main.h"
 #include "nvim/misc1.h"
 #include "nvim/state.h"
-#include "nvim/log.h"
+#include "nvim/msgpack_rpc/channel.h"
 
 #define READ_BUFFER_SIZE 0xfff
 #define INPUT_BUFFER_SIZE (READ_BUFFER_SIZE * 4)
@@ -342,11 +342,9 @@ static bool input_poll(int ms)
   }
 
   if ((ms == - 1 || ms > 0) && !events_enabled && !input_eof) {
-    // We have discovered that the pending input will provoke a blocking wait.
-    // Process any events marked with priority `kEvPriorityAsync`: these events
-    // must be handled after flushing input. See channel.c:handle_request #6247
+    // The pending input provoked a blocking wait. Do special events now. #6247
     blocking = true;
-    multiqueue_process_priority(main_loop.events, kEvPriorityAsync);
+    multiqueue_process_events(ch_before_blocking_events);
   }
   LOOP_PROCESS_EVENTS_UNTIL(&main_loop, NULL, ms, input_ready() || input_eof);
   blocking = false;