Add interrupt check.

Author: samuel-williams-shopify

src/ruby/ext/grpc/rb_completion_queue.c

@@ -107,6 +107,11 @@ grpc_event rb_completion_queue_pluck(grpc_completion_queue* queue, void* tag,
     if (next_call.interrupted) {
       fprintf(stderr, "[GRPC DEBUG] Loop iteration %d: interrupted=1, checking if signal is pending...\n", loop_count);
       fflush(stderr);
+      // Check if there's actually a signal pending (SIGINT/SIGTERM)
+      // If rb_thread_check_ints() raises an exception, it means there's a real signal
+      // If it returns normally, the interruption was spurious and we should retry
+      rb_thread_check_ints();
+      // If we get here, interruption was spurious - retry
       fprintf(stderr, "[GRPC DEBUG] Loop iteration %d: No signal pending, was spurious, RETRYING\n", loop_count);
       fflush(stderr);
     }