iPhone development: pointer being freed was not allocated
- by w4nderlust
Hello, i got this message from the debugger:
Pixture(1257,0xa0610500) malloc: *** error for object 0x21a8000: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug
so i did a bit of tracing and got:
(gdb) shell malloc_history 1257 0x21a8000
ALLOC 0x2196a00-0x21a89ff [size=73728]: thread_a0610500 |start | main | UIApplicationMain | GSEventRun | GSEventRunModal | CFRunLoopRunInMode | CFRunLoopRunSpecific | __CFRunLoopDoObservers | CA::Transaction::observer_callback(__CFRunLoopObserver*, unsigned long, void*) | CA::Transaction::commit() | CA::Context::commit_transaction(CA::Transaction*) | CALayerDisplayIfNeeded | -[CALayer _display] | CABackingStoreUpdate | backing_callback(CGContext*, void*) | -[CALayer drawInContext:] | -[UIView(CALayerDelegate) drawLayer:inContext:] | -[AvatarView drawRect:] | -[AvatarView overlayPNG:] | +[UIImageUtility createMaskOf:] | UIGraphicsGetImageFromCurrentImageContext | CGBitmapContextCreateImage | create_bitmap_data_provider | malloc | malloc_zone_malloc
and i really can't understand what i am doing wrong. here's the code of the [UIImageUtility createMaskOf:] function:
+ (UIImage *)createMaskOf:(UIImage *)source {
CGRect rect = CGRectMake(0, 0, source.size.width, source.size.height);
UIGraphicsBeginImageContext(CGSizeMake(source.size.width, source.size.height));
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(context, 0, source.size.height);
CGContextScaleCTM(context, 1.0, -1.0);
UIImage *original = [self createGrayCopy:source];
CGContextRef context2 = CGBitmapContextCreate(NULL, source.size.width, source.size.height, 8, 4 * source.size.width,
CGColorSpaceCreateDeviceRGB(), kCGImageAlphaNoneSkipLast);
CGContextDrawImage(context2, CGRectMake(0, 0, source.size.width, source.size.height), original.CGImage);
CGImageRef unmasked = CGBitmapContextCreateImage(context2);
const float myMaskingColorsFrameColor[6] = { 1,256,1,256,1,256 };
CGImageRef mask = CGImageCreateWithMaskingColors(unmasked, myMaskingColorsFrameColor);
CGContextSetRGBFillColor (context, 256,256,256, 1);
CGContextFillRect(context, rect);
CGContextDrawImage(context, rect, mask);
UIImage *whiteMasked = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return whiteMasked;
}
the other custom function called before that is the following:
- (UIImage *)overlayPNG:(SinglePart *)sp {
NSLog([sp description]);
// Rect and context setup
CGRect rect = CGRectMake(0, 0, sp.image.size.width, sp.image.size.height);
NSLog(@"%f x %f", sp.image.size.width, sp.image.size.height);
// Create an image of a color filled rectangle
UIImage *baseColor = nil;
if (sp.hasOwnColor) {
baseColor = [UIImageUtility imageWithRect:rect ofColor:sp.color];
} else {
SinglePart *facePart = [editingAvatar.face.partList objectAtIndex:0];
baseColor = [UIImageUtility imageWithRect:rect ofColor:facePart.color];
}
// Crete the mask of the layer
UIImage *mask = [UIImageUtility createMaskOf:sp.image];
mask = [UIImageUtility createGrayCopy:mask];
// Create a new context for merging the overlay and a mask of the layer
UIGraphicsBeginImageContext(CGSizeMake(sp.image.size.width, sp.image.size.height));
CGContextRef context2 = UIGraphicsGetCurrentContext();
// Adjust the coordinate system so that the origin
// is in the lower left corner of the view and the
// y axis points up
CGContextTranslateCTM(context2, 0, sp.image.size.height);
CGContextScaleCTM(context2, 1.0, -1.0);
// Create masked overlay color layer
CGImageRef MaskedImage = CGImageCreateWithMask (baseColor.CGImage, mask.CGImage);
// Draw the base color layer
CGContextDrawImage(context2, rect, MaskedImage);
// Get the result of the masking
UIImage* overlayMasked = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIGraphicsBeginImageContext(CGSizeMake(sp.image.size.width, sp.image.size.height));
CGContextRef context = UIGraphicsGetCurrentContext();
// Adjust the coordinate system so that the origin
// is in the lower left corner of the view and the
// y axis points up
CGContextTranslateCTM(context, 0, sp.image.size.height);
CGContextScaleCTM(context, 1.0, -1.0);
// Get the result of the blending of the masked overlay and the base image
CGContextDrawImage(context, rect, overlayMasked.CGImage);
// Set the blend mode for the next drawn image
CGContextSetBlendMode(context, kCGBlendModeOverlay);
// Component image drawn
CGContextDrawImage(context, rect, sp.image.CGImage);
UIImage* blendedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
CGImageRelease(MaskedImage);
return blendedImage;
}