Log SDL keybaord events as part of RUNTIME_DEBUG.

Also, test_sdl_key_test.c to test_interactive.py.  This test was not
being run anywhere else and serves as simple way to test/debug keyboard
events.

Also, only set the `RUNTIME_DEBUG` default if the user does not
explicitly set it themselves.  This allows for `-sSOCKETS_DEBUG
-sRUNTIM_DEBUG=0` to opt out of the `RUNTIME_DEBUG` channel.

Finally, disable the `RUNTIME_DEBUG` traces that occur during turns of
the event loop unless `RUNTIME_DEBUG` is set to 2.  This avoids flooding
the console will messages in applications that are using the event loop.

Author: sbc100

src/library.js

@@ -2160,7 +2160,7 @@ addToLibrary({
       return;
     }
 #endif
-#if RUNTIME_DEBUG
+#if RUNTIME_DEBUG == 2
     dbg(`maybeExit: user callback done: runtimeKeepaliveCounter=${runtimeKeepaliveCounter}`);
 #endif
     if (!keepRuntimeAlive()) {

src/library_sdl.js

@@ -930,7 +930,9 @@ var LibrarySDL = {
       switch (event.type) {
         case 'keydown': case 'keyup': {
           var down = event.type === 'keydown';
-          //dbg('Received key event: ' + event.keyCode);
+#if RUNTIME_DEBUG
+          dbg(`received ${event.type} event: keyCode=${event.keyCode}, key=${event.key}, code=${event.code}`);
+#endif
           var key = SDL.lookupKeyCodeForEvent(event);
           var scan;
           if (key >= 1024) {

src/runtime_stack_check.js

@@ -36,7 +36,7 @@ function checkStackCookie() {
   if (ABORT) return;
 #endif
   var max = _emscripten_stack_get_end();
-#if RUNTIME_DEBUG
+#if RUNTIME_DEBUG == 2
   dbg(`checkStackCookie: ${ptrToString(max)}`);
 #endif
   // See writeStackCookie().

src/settings.js

@@ -2137,7 +2137,9 @@ var TRUSTED_TYPES = false;
 // settings is *only* needed when also explicitly targeting older browsers.
 var POLYFILL = true;
 
-// If true, add tracing to core runtime functions.
+// If non-zero, add tracing to core runtime functions.  Can be set to 2 for
+// extra tracing (for example, tracing that occors on each turn of the event
+// loop or each user callback which can flood the console).
 // This setting is enabled by default if any of the following debugging settings
 // are enabled:
 // - PTHREADS_DEBUG
@@ -2151,7 +2153,7 @@ var POLYFILL = true;
 // - SOCKET_DEBUG
 // - FETCH_DEBUG
 // [link]
-var RUNTIME_DEBUG = false;
+var RUNTIME_DEBUG = 0;
 
 // Include JS library symbols that were previously part of the default runtime.
 // Without this, such symbols can be made available by adding them to

test/test_interactive.py

@@ -48,6 +48,9 @@ def test_sdl_touch(self):
   def test_sdl_wm_togglefullscreen(self):
     self.btest_exit('test_sdl_wm_togglefullscreen.c')
 
+  def test_sdl_key_test(self):
+    self.btest_exit('test_sdl_key_test.c', args=['-sRUNTIME_DEBUG'])
+
   def test_sdl_fullscreen_samecanvassize(self):
     self.btest_exit('test_sdl_fullscreen_samecanvassize.c')
 

tools/link.py

@@ -666,18 +666,19 @@ def phase_linker_setup(options, state, newargs):
   if options.cpu_profiler:
     options.post_js.append(utils.path_from_root('src/cpuprofiler.js'))
 
-  if not settings.RUNTIME_DEBUG:
-    settings.RUNTIME_DEBUG = bool(settings.LIBRARY_DEBUG or
-                                  settings.GL_DEBUG or
-                                  settings.DYLINK_DEBUG or
-                                  settings.OPENAL_DEBUG or
-                                  settings.SYSCALL_DEBUG or
-                                  settings.WEBSOCKET_DEBUG or
-                                  settings.SOCKET_DEBUG or
-                                  settings.FETCH_DEBUG or
-                                  settings.EXCEPTION_DEBUG or
-                                  settings.PTHREADS_DEBUG or
-                                  settings.ASYNCIFY_DEBUG)
+  # Unless RUNTIME_DEBUG is explicitly set then we enable it when any of the
+  # more specfic debug settings are present.
+  default_setting('RUNTIME_DEBUG', int(settings.LIBRARY_DEBUG or
+                                       settings.GL_DEBUG or
+                                       settings.DYLINK_DEBUG or
+                                       settings.OPENAL_DEBUG or
+                                       settings.SYSCALL_DEBUG or
+                                       settings.WEBSOCKET_DEBUG or
+                                       settings.SOCKET_DEBUG or
+                                       settings.FETCH_DEBUG or
+                                       settings.EXCEPTION_DEBUG or
+                                       settings.PTHREADS_DEBUG or
+                                       settings.ASYNCIFY_DEBUG))
 
   if options.memory_profiler:
     settings.MEMORYPROFILER = 1