Add LuaSkin canaries to hs.uielement.watcher, hs.audiodevice.watcher …

…and hs.keycodes
Hammerspoon · May 1, 2021 · da2f41a · da2f41a
1 parent e5c2ced
commit da2f41a
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Showing 5 changed files with 38 additions and 16 deletions.
diff --git a/Hammerspoon/HSuicore.h b/Hammerspoon/HSuicore.h
@@ -38,6 +38,7 @@
 @property (nonatomic) BOOL running;
 @property (nonatomic) pid_t pid;
 @property (nonatomic) BOOL watchDestroyed;
+@property (nonatomic) LSGCCanary lsCanary;
 
 -(HSuielementWatcher *)initWithElement:(HSuielement *)element callbackRef:(int)callbackRef userdataRef:(int)userdataRef;
 -(void)dealloc;

diff --git a/Hammerspoon/HSuicore.m b/Hammerspoon/HSuicore.m
@@ -333,6 +333,7 @@ -(id)newWatcherAtIndex:(int)callbackRefIndex withUserdataAtIndex:(int)userDataRe
  HSuielementWatcher *watcher = [[HSuielementWatcher alloc] initWithElement:self
  callbackRef:(int)callbackRef
  userdataRef:(int)userDataRef];
+ watcher.lsCanary = [skin createGCCanary];
  return watcher;
 }
 
@@ -378,10 +379,11 @@ -(NSString *)getSelectedText {
 
 static void watcher_observer_callback(AXObserverRef observer __unused, AXUIElementRef element,
  CFStringRef notificationName, void* contextData) {
+ HSuielementWatcher *watcher = (__bridge HSuielementWatcher *)contextData;
  LuaSkin *skin = [LuaSkin sharedWithState:NULL];
+ [skin checkGCCanary:watcher.lsCanary];
  _lua_stackguard_entry(skin.L);
 
- HSuielementWatcher *watcher = (__bridge HSuielementWatcher *)contextData;
 
  [skin pushLuaRef:watcher.refTable ref:watcher.handlerRef]; // Callback function
 

diff --git a/extensions/audiodevice/watcher.m b/extensions/audiodevice/watcher.m
@@ -16,6 +16,7 @@
 typedef struct _audiodevice_watcher_t {
  int callback;
  BOOL running;
+ LSGCCanary lsCanary;
 } audiodevice_watcher;
 
 const AudioObjectPropertySelector watchSelectors[] = {
@@ -46,11 +47,17 @@ OSStatus audiodevicewatcher_callback(AudioDeviceID deviceID, UInt32 numAddresses
 
  //NSLog(@"%i addresses to check", numAddresses);
  LuaSkin *skin = [LuaSkin sharedWithState:NULL];
- _lua_stackguard_entry(skin.L);
+
  if (!theWatcher) {
  [skin logWarn:@"hs.audiodevice.watcher callback fired, but theWatcher is nil. This is a bug"];
  return;
  }
+
+ if (![skin checkGCCanary:theWatcher->lsCanary]) {
+ return;
+ }
+ _lua_stackguard_entry(skin.L);
+
  if (theWatcher->callback == LUA_NOREF) {
  [skin logWarn:@"hs.audiodevice.watcher callback fired, but there is no callback. This is a bug"];
  } else {
@@ -96,6 +103,7 @@ static int audiodevicewatcher_setCallback(lua_State *L) {
  memset(theWatcher, 0, sizeof(audiodevice_watcher));
  theWatcher->running = NO;
  theWatcher->callback = LUA_NOREF;
+ theWatcher->lsCanary = [skin createGCCanary];
  }
 
  theWatcher->callback = [skin luaUnref:refTable ref:theWatcher->callback];
@@ -215,6 +223,7 @@ static int audiodevicewatcher_gc(lua_State *L) {
  if (theWatcher) {
  audiodevicewatcher_stop(L);
  theWatcher->callback = [skin luaUnref:refTable ref:theWatcher->callback];
+ [skin destroyGCCanary:&(theWatcher->lsCanary)];
  free(theWatcher);
  theWatcher = nil;
  }

diff --git a/extensions/keycodes/internal.m b/extensions/keycodes/internal.m
@@ -192,6 +192,7 @@ int keycodes_cachemap(lua_State* L) {
 
 @interface MJKeycodesObserver : NSObject
 @property int ref;
+@property LSGCCanary lsCanary;
 @end
 
 @implementation MJKeycodesObserver
@@ -204,25 +205,24 @@ - (instancetype)init {
  return self ;
 }
 
-- (void) _inputSourceChanged:(NSNotification*)__unused note {
- [self performSelectorOnMainThread:@selector(inputSourceChanged:)
- withObject:nil
- waitUntilDone:YES];
-}
-
 - (void) inputSourceChanged:(NSNotification*)__unused note {
- if (self.ref != LUA_NOREF) {
- LuaSkin *skin = [LuaSkin sharedWithState:NULL];
- _lua_stackguard_entry(skin.L);
- [skin pushLuaRef:refTable ref:self.ref];
- [skin protectedCallAndError:@"hs.keycodes.inputSourceChanged" nargs:0 nresults:0];
- _lua_stackguard_exit(skin.L);
- }
+ dispatch_async(dispatch_get_main_queue(), ^{
+ if (self.ref != LUA_NOREF) {
+ LuaSkin *skin = [LuaSkin sharedWithState:NULL];
+ if (![skin checkGCCanary:self.lsCanary]) {
+ return;
+ }
+ _lua_stackguard_entry(skin.L);
+ [skin pushLuaRef:refTable ref:self.ref];
+ [skin protectedCallAndError:@"hs.keycodes.inputSourceChanged" nargs:0 nresults:0];
+ _lua_stackguard_exit(skin.L);
+ }
+ });
 }
 
 - (void) start {
  [[NSNotificationCenter defaultCenter] addObserver:self
- selector:@selector(_inputSourceChanged:)
+ selector:@selector(inputSourceChanged:)
  name:NSTextInputContextKeyboardSelectionDidChangeNotification
  object:nil];
  /* This should have made things better, but it seems to cause crashes for some, possibly because the paired removeObserver call is wrong?
@@ -257,6 +257,7 @@ static int keycodes_newcallback(lua_State* L) {
 
  MJKeycodesObserver* observer = [[MJKeycodesObserver alloc] init];
  observer.ref = ref;
+ observer.lsCanary = [skin createGCCanary];
  [observer start];
 
  void** ud = lua_newuserdata(L, sizeof(id));
@@ -277,6 +278,11 @@ static int keycodes_callback_gc(lua_State* L) {
  LuaSkin *skin = [LuaSkin sharedWithState:L];
 
  MJKeycodesObserver* observer = (__bridge_transfer MJKeycodesObserver*)*(void**)luaL_checkudata(L, 1, USERDATA_TAG);
+
+ LSGCCanary tmplsCanary = observer.lsCanary;
+ [skin destroyGCCanary:&tmplsCanary];
+ observer.lsCanary = tmplsCanary;
+
  [observer stop];
 
  observer.ref = [skin luaUnref:refTable ref:observer.ref];

diff --git a/extensions/uielement/watcher.m b/extensions/uielement/watcher.m
@@ -150,6 +150,10 @@ static int userdata_gc(lua_State* L) {
  [skin checkArgs:LS_TUSERDATA, USERDATA_TAG, LS_TBREAK];
  HSuielementWatcher *watcher = get_objectFromUserdata(__bridge_transfer HSuielementWatcher, L, 1, USERDATA_TAG);
  if (watcher) {
+ LSGCCanary tmplsCanary = watcher.lsCanary;
+ [skin destroyGCCanary:&tmplsCanary];
+ watcher.lsCanary = tmplsCanary;
+
  watcher.selfRefCount--;
  if (watcher.selfRefCount == 0) {
  [watcher stop];