Thanks ronie! This is important for the future of Pharo. On Thu, Nov 2, 2017 at 2:48 AM, Ronie Salgado <roniesalg@gmail.com> wrote:

Hi,

I finally managed to track the problem with keyboard events with OSWindow. However, I cannot fix it without introducing a crash in an autorelease, or a memory leak.

The SDL2 problem can be fixed by applying the following patch:

diff --git a/platforms/iOS/vm/Common/Classes/sqSqueakEventsAPI.m b/platforms/iOS/vm/Common/Classes/sqSqueakEventsAPI.m index 94c3c4c82..4b5aec8c5 100644 --- a/platforms/iOS/vm/Common/Classes/sqSqueakEventsAPI.m +++ b/platforms/iOS/vm/Common/Classes/sqSqueakEventsAPI.m @@ -100,9 +100,7 @@ sqInt ioProcessEvents(void) {

// We need to run the vmIOProcessEvents even if we are using SDL2, // otherwise we end with some double free errors in an autorelease pool. - vmIOProcessEvents(); - if(ioProcessEventsHandler && ioProcessEventsHandler != vmIOProcessEvents) - ioProcessEventsHandler(); + ioProcessEventsHandler();

However, this introduces a crash in an Objective-C autorelease pool, in at leas two locations:

diff --git a/platforms/iOS/vm/OSX/sqSqueakOSXApplication+events.m b/platforms/iOS/vm/OSX/sqSqueakOSXApplication+events.m index 4f2ac06ea..c1ec3e1ea 100644 --- a/platforms/iOS/vm/OSX/sqSqueakOSXApplication+events.m +++ b/platforms/iOS/vm/OSX/sqSqueakOSXApplication+events.m @@ -152,9 +152,10 @@ - (void) recordCharEvent:(NSString *) unicodeString fromView: (NSView <sqSqueakO } }

- NSString *lookupString = AUTORELEASEOBJ([[NSString alloc] initWithCharacters: &unicode length: 1]); + NSString *lookupString = [[NSString alloc] initWithCharacters: &unicode length: 1]; [lookupString getBytes: &macRomanCharacter maxLength: 1 usedLength: NULL encoding: NSMacOSRomanStringEncoding options: 0 range: picker remainingRange: NULL]; + [lookupString release];

evt.pressCode = EventKeyDown; unsigned short keyCodeRemembered = evt.charCode;

diff --git a/platforms/iOS/vm/OSX/sqSqueakOSXOpenGLView.m b/platforms/iOS/vm/OSX/sqSqueakOSXOpenGLView.m index c441332a3..72aa8c42d 100644 --- a/platforms/iOS/vm/OSX/sqSqueakOSXOpenGLView.m +++ b/platforms/iOS/vm/OSX/sqSqueakOSXOpenGLView.m @@ -747,7 +747,7 @@ - (NSString *) dealWithOpenStepChars: (NSString *) openStep {

-(void)keyDown:(NSEvent*)theEvent { - keyBoardStrokeDetails *aKeyBoardStrokeDetails = AUTORELEASEOBJ([[keyBoardStrokeDetails alloc] init]); + keyBoardStrokeDetails *aKeyBoardStrokeDetails = ([[keyBoardStrokeDetails alloc] init]); aKeyBoardStrokeDetails.keyCode = [theEvent keyCode]; aKeyBoardStrokeDetails.modifierFlags = [theEvent modifierFlags];

@@ -757,6 +757,8 @@ -(void)keyDown:(NSEvent*)theEvent { [self interpretKeyEvents: down]; self.lastSeenKeyBoardStrokeDetails = NULL; } + + //[aKeyBoardStrokeDetails release]; }

In the last location I had to comment my attempt on doing a manual release because it introduces a crash.

OSWindow can be tested in a fresh Pharo image by doing the following in a workspace:

...

FFIExternalStructure allSubclassesDo: #rebuildFieldAccessors. SDL_Event initialize. SDL2 findSDL2. OSWindowWorldMorph new open.

I have attached the full diff with my bug fix attempt. I hope that someone that is more familiar with the OS X platform code and Objective-C can remove these autoreleases without introducing crashes.

When executed in a debugger, the crash is detected in SDL2 Cocoa_PumpEvents:

...

...

void

Cocoa_PumpEvents(_THIS)

{ @autoreleasepool

{

/* Update activity every 30 seconds to prevent screensaver */

SDL_VideoData *data = (SDL_VideoData *)_this->driverdata;

if (_this->suspend_screensaver && !data->screensaver_use_iopm) {

Uint32 now = SDL_GetTicks();

if (!data->screensaver_activity ||

SDL_TICKS_PASSED(now, data->screensaver_activity + 30000)) {

UpdateSystemActivity(UsrActivity);

data->screensaver_activity = now;

}

}

for ( ; ; ) {

NSEvent *event = [NSApp nextEventMatchingMask:NSAnyEventMask untilDate:[NSDate distantPast] inMode:NSDefaultRunLoopMode dequeue:YES ];

if ( event == nil ) {

break;

}

if (!s_bShouldHandleEventsInSDLApplication) {

Cocoa_DispatchEvent(event);

}

// Pass events down to SDLApplication to be handled in sendEvent:

[NSApp sendEvent:event];

}

}}

For tracking these actual calls to #autorelease, I had to set a breakpoint on the #autorelease Objective-C selector, and log the stacktrace to find where it is called in our code.

Best regards, Ronie