[ThreadPool] Sort items in the queue based on priority

include/rofi-types.h

@@ -370,6 +370,7 @@ typedef struct rofi_int_matcher_t {
  */
 typedef struct _thread_state {
   void (*callback)(struct _thread_state *t, gpointer data);
+  int priority;
 } thread_state;
 
 extern GThreadPool *tpool;

source/rofi-icon-fetcher.c

@@ -411,6 +411,7 @@ uint32_t rofi_icon_fetcher_query_advanced(const char *name, const int wsize,
 
   // Push into fetching queue.
   sentry->state.callback = rofi_icon_fetcher_worker;
+  sentry->state.priority = G_PRIORITY_LOW;
   g_thread_pool_push(tpool, sentry, NULL);
 
   return sentry->uid;
@@ -447,6 +448,7 @@ uint32_t rofi_icon_fetcher_query(const char *name, const int size) {
 
   // Push into fetching queue.
   sentry->state.callback = rofi_icon_fetcher_worker;
+  sentry->state.priority = G_PRIORITY_LOW;
   g_thread_pool_push(tpool, sentry, NULL);
 
   return sentry->uid;

source/view.c

@@ -1444,6 +1444,7 @@ static gboolean rofi_view_refilter_real(RofiViewState *state) {
       states[i].plen = plen;
       states[i].pattern = pattern;
       states[i].st.callback = filter_elements;
+      states[i].st.priority = G_PRIORITY_HIGH;
       if (i > 0) {
         g_thread_pool_push(tpool, &states[i], NULL);
       }
@@ -2624,6 +2625,15 @@ void rofi_view_cleanup() {
 
   input_history_save();
 }
+
+static int rofi_thread_workers_sort(gconstpointer a,gconstpointer b, gpointer data G_GNUC_UNUSED)
+{
+  thread_state *tsa = (thread_state *)a;
+  thread_state *tsb = (thread_state *)b;
+  // lower number is lower priority..  a is sorted above is a > b. 
+  return tsa->priority-tsb->priority;
+}
+
 void rofi_view_workers_initialize(void) {
   TICK_N("Setup Threadpool, start");
   if (config.threads == 0) {
@@ -2649,6 +2659,7 @@ void rofi_view_workers_initialize(void) {
     g_error_free(error);
     exit(EXIT_FAILURE);
   }
+  g_thread_pool_set_sort_function(tpool, rofi_thread_workers_sort, NULL);
   TICK_N("Setup Threadpool, done");
 }
 void rofi_view_workers_finalize(void) {