From 84cab492b29fc5f057162c698612696b11c31f3f Mon Sep 17 00:00:00 2001
From: Jamiras <jamirasmt@gmail.com>
Date: Mon, 8 Nov 2021 09:35:25 -0700
Subject: [PATCH] add task_in_on_main_thread function

---
 cheevos/cheevos.c                           | 60 ++++++++++++---------
 libretro-common/include/queues/task_queue.h |  2 +
 libretro-common/queues/task_queue.c         | 11 ++++
 3 files changed, 49 insertions(+), 24 deletions(-)

diff --git a/cheevos/cheevos.c b/cheevos/cheevos.c
index 6d9190d49a..5074e46472 100644
--- a/cheevos/cheevos.c
+++ b/cheevos/cheevos.c
@@ -823,13 +823,16 @@ static void rcheevos_toggle_hardcore_active(rcheevos_locals_t* locals)
       if (rewind_enable)
       {
 #ifdef HAVE_THREADS
-         /* have to "schedule" this. 
-          * CMD_EVENT_REWIND_DEINIT should 
-          * only be called on the main thread */
-         rcheevos_locals.queued_command = CMD_EVENT_REWIND_DEINIT;
-#else
-         command_event(CMD_EVENT_REWIND_DEINIT, NULL);
+         if (!task_is_on_main_thread())
+         {
+            /* have to "schedule" this.
+             * CMD_EVENT_REWIND_DEINIT should
+             * only be called on the main thread */
+            rcheevos_locals.queued_command = CMD_EVENT_REWIND_DEINIT;
+         }
+         else
 #endif
+            command_event(CMD_EVENT_REWIND_DEINIT, NULL);
       }
    }
    else
@@ -849,13 +852,16 @@ static void rcheevos_toggle_hardcore_active(rcheevos_locals_t* locals)
       if (rewind_enable)
       {
 #ifdef HAVE_THREADS
-         /* have to "schedule" this. 
-          * CMD_EVENT_REWIND_INIT should 
-          * only be called on the main thread */
-         rcheevos_locals.queued_command = CMD_EVENT_REWIND_INIT;
-#else
-         command_event(CMD_EVENT_REWIND_INIT, NULL);
+         if (!task_is_on_main_thread())
+         {
+            /* have to "schedule" this.
+             * CMD_EVENT_REWIND_INIT should
+             * only be called on the main thread */
+            rcheevos_locals.queued_command = CMD_EVENT_REWIND_INIT;
+         }
+         else
 #endif
+            command_event(CMD_EVENT_REWIND_INIT, NULL);
       }
    }
 
@@ -1343,12 +1349,15 @@ static void rcheevos_start_session(void)
       if (settings->bools.rewind_enable)
       {
 #ifdef HAVE_THREADS
-         /* Have to "schedule" this. CMD_EVENT_REWIND_INIT should 
-          * only be called on the main thread */
-         rcheevos_locals.queued_command = CMD_EVENT_REWIND_INIT;
-#else
-         command_event(CMD_EVENT_REWIND_INIT, NULL);
+         if (!task_is_on_main_thread())
+         {
+            /* Have to "schedule" this. CMD_EVENT_REWIND_INIT should
+             * only be called on the main thread */
+            rcheevos_locals.queued_command = CMD_EVENT_REWIND_INIT;
+         }
+         else
 #endif
+            command_event(CMD_EVENT_REWIND_INIT, NULL);
       }
    }
 #endif
@@ -1422,15 +1431,18 @@ static void rcheevos_fetch_game_data(void)
       if (settings->bools.rewind_enable)
       {
 #ifdef HAVE_THREADS
-         /* have to "schedule" this. CMD_EVENT_REWIND_DEINIT should only be called on the main thread */
-         rcheevos_locals.queued_command = CMD_EVENT_REWIND_DEINIT;
+         if (!task_is_on_main_thread())
+         {
+            /* have to "schedule" this. CMD_EVENT_REWIND_DEINIT should only be called on the main thread */
+            rcheevos_locals.queued_command = CMD_EVENT_REWIND_DEINIT;
 
-         /* wait for rewind to be disabled */
-         while (rcheevos_locals.queued_command != CMD_EVENT_NONE)
-            retro_sleep(1);
-#else
-         command_event(CMD_EVENT_REWIND_DEINIT, NULL);
+            /* wait for rewind to be disabled */
+            while (rcheevos_locals.queued_command != CMD_EVENT_NONE)
+               retro_sleep(1);
+         }
+         else
 #endif
+            command_event(CMD_EVENT_REWIND_DEINIT, NULL);
       }
    }
 #endif
diff --git a/libretro-common/include/queues/task_queue.h b/libretro-common/include/queues/task_queue.h
index 1d39cdb439..c91d4a73ca 100644
--- a/libretro-common/include/queues/task_queue.h
+++ b/libretro-common/include/queues/task_queue.h
@@ -191,6 +191,8 @@ char* task_get_title(retro_task_t *task);
 
 void* task_get_data(retro_task_t *task);
 
+bool task_is_on_main_thread(void);
+
 void task_queue_set_threaded(void);
 
 void task_queue_unset_threaded(void);
diff --git a/libretro-common/queues/task_queue.c b/libretro-common/queues/task_queue.c
index 58ede3e805..6441b54efd 100644
--- a/libretro-common/queues/task_queue.c
+++ b/libretro-common/queues/task_queue.c
@@ -66,6 +66,7 @@ static struct retro_task_impl *impl_current = NULL;
 static bool task_threaded_enable            = false;
 
 #ifdef HAVE_THREADS
+static uintptr_t main_thread_id             = NULL;
 static slock_t *running_lock                = NULL;
 static slock_t *finished_lock               = NULL;
 static slock_t *property_lock               = NULL;
@@ -614,6 +615,7 @@ void task_queue_init(bool threaded, retro_task_queue_msg_t msg_push)
    impl_current = &impl_regular;
 
 #ifdef HAVE_THREADS
+   main_thread_id = sthread_get_current_thread_id();
    if (threaded)
    {
       task_threaded_enable = true;
@@ -750,6 +752,15 @@ void task_queue_retriever_info_free(task_retriever_info_t *list)
    }
 }
 
+bool task_is_on_main_thread(void)
+{
+#ifdef HAVE_THREADS
+   return sthread_get_current_thread_id() == main_thread_id;
+#else
+   return true;
+#endif
+}
+
 void task_set_finished(retro_task_t *task, bool finished)
 {
    SLOCK_LOCK(property_lock);