Use ARC

- Fix various memory leaks
- Remove unnecessary code because of ARC
- Update README

Author: Michael Potter

FastImageCache/FICImageCache.h

@@ -34,7 +34,7 @@ typedef void (^FICImageRequestCompletionBlock)(UIImage *sourceImage);
  @discussion The delegate is responsible for asynchronously providing the source image for an entity. Optionally, the delegate can require that all formats in a format
  family for a particular entity be processed. Any errors that occur in the image cache are also communicated back to the delegate.
  */
-@property(nonatomic, assign) id <FICImageCacheDelegate> delegate;
+@property (nonatomic, weak) id <FICImageCacheDelegate> delegate;
 
 ///---------------------------------------
 /// @name Accessing the Shared Image Cache

FastImageCache/FICImageCache.m

@@ -26,7 +26,7 @@ @interface FICImageCache () {
     NSMutableDictionary *_formats;
     NSMutableDictionary *_imageTables;
     NSMutableDictionary *_requests;
-    id <FICImageCacheDelegate> _delegate;
+    __weak id <FICImageCacheDelegate> _delegate;
 
     BOOL _delegateImplementsShouldProcessAllFormatsInFamilyForEntity;
     BOOL _delegateImplementsErrorDidOccurWithMessage;
@@ -83,14 +83,6 @@ - (id)init {
     return self;
 }
 
-- (void)dealloc {
-    [_formats release];
-    [_imageTables release];
-    [_requests release];
-    
-    [super dealloc];
-}
-
 #pragma mark - Working with Formats
 
 - (void)setFormats:(NSArray *)formats {
@@ -106,7 +98,6 @@ - (void)setFormats:(NSArray *)formats {
                 // Only initialize an image table for this format if it is needed on the current device.
                 FICImageTable *imageTable = [[FICImageTable alloc] initWithFormat:imageFormat];
                 [_imageTables setObject:imageTable forKey:formatName];
-                [imageTable release];
                 [_formats setObject:imageFormat forKey:formatName];
 
                 [imageTableFiles addObject:[[imageTable tableFilePath] lastPathComponent]];
@@ -144,7 +135,7 @@ - (NSArray *)formatsWithFamily:(NSString *)family {
         }
     }
 
-    return [[formats copy] autorelease];
+    return [formats copy];
 }
 
 #pragma mark - Retrieving Images
@@ -175,8 +166,6 @@ - (BOOL)_retrieveImageForEntity:(id <FICEntity>)entity withFormatName:(NSString
                     completionBlock(entity, formatName, image);
                 });
             }
-            
-            [image release];    // Already retained by the block
         });
     } else {
         UIImage *image = [imageTable newImageForEntityUUID:entityUUID sourceImageUUID:sourceImageUUID];
@@ -192,8 +181,6 @@ - (BOOL)_retrieveImageForEntity:(id <FICEntity>)entity withFormatName:(NSString
                     });
                 }
             }
-            
-            [image release];    // Already retained by the block
         };
 
         if (image == nil && _delegate != nil) {
@@ -274,7 +261,7 @@ static void _FICAddCompletionBlockForEntity(NSString *formatName, NSMutableDicti
             [completionBlocks setObject:blocksArray forKey:formatName];
         }
 
-        FICImageCacheCompletionBlock completionBlockCopy = [[completionBlock copy] autorelease];
+        FICImageCacheCompletionBlock completionBlockCopy = [completionBlock copy];
         [blocksArray addObject:completionBlockCopy];
     }
 }
@@ -286,7 +273,7 @@ - (void)setImage:(UIImage *)image forEntity:(id <FICEntity>)entity withFormatNam
         NSDictionary *completionBlocksDictionary = nil;
 
         if (completionBlock != nil) {
-            completionBlocksDictionary = [NSDictionary dictionaryWithObject:[NSArray arrayWithObject:[[completionBlock copy] autorelease]] forKey:formatName];
+            completionBlocksDictionary = [NSDictionary dictionaryWithObject:[NSArray arrayWithObject:[completionBlock copy]] forKey:formatName];
         }
 
         NSString *entityUUID = [entity UUID];
@@ -360,8 +347,6 @@ - (void)_processImage:(UIImage *)image forEntity:(id <FICEntity>)entity imageTab
                     }
                 });
             }
-            
-            [resultImage release];
         });
     }
 }

FastImageCache/FICImageFormat.m

@@ -61,7 +61,7 @@ - (void)setImageSize:(CGSize)imageSize {
 #pragma mark - Object Lifecycle
 
 + (instancetype)formatWithName:(NSString *)name family:(NSString *)family imageSize:(CGSize)imageSize isOpaque:(BOOL)isOpaque maximumCount:(NSInteger)maximumCount devices:(FICImageFormatDevices)devices {
-    FICImageFormat *imageFormat = [[[FICImageFormat alloc] init] autorelease];
+    FICImageFormat *imageFormat = [[FICImageFormat alloc] init];
 
     [imageFormat setName:name];
     [imageFormat setFamily:family];
@@ -73,13 +73,6 @@ + (instancetype)formatWithName:(NSString *)name family:(NSString *)family imageS
     return imageFormat;
 }
 
-- (void)dealloc {
-    [_name release];
-    [_family release];
-    
-    [super dealloc];
-}
-
 #pragma mark - Working with Dictionary Representations
 
 - (NSDictionary *)dictionaryRepresentation {

FastImageCache/FICImageTable.h

@@ -42,7 +42,7 @@ extern NSString *const FICImageTableScreenScaleKey;
 /**
  The image format that describes the image table.
  */
-@property (nonatomic, retain, readonly) FICImageFormat *imageFormat;
+@property (nonatomic, strong, readonly) FICImageFormat *imageFormat;
 
 ///-----------------------------------------------
 /// @name Accessing Information about Image Tables

FastImageCache/FICImageTable.m

@@ -49,7 +49,7 @@ @interface FICImageTable () {
     size_t _chunkLength;
     NSInteger _chunkCount;
 
-    CFMutableDictionaryRef _chunkDictionary;
+    NSMapTable *_chunkMapTable;
     NSMutableArray *_recentChunks;
     NSRecursiveLock *_lock;
 
@@ -104,9 +104,9 @@ + (NSString *)directoryPath {
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
         NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
-        __directoryPath = [[[paths objectAtIndex:0] stringByAppendingPathComponent:@"ImageTables"] retain];
+        __directoryPath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"ImageTables"];
 
-        NSFileManager *fileManager = [[[NSFileManager alloc] init] autorelease];
+        NSFileManager *fileManager = [[NSFileManager alloc] init];
         BOOL directoryExists = [fileManager fileExistsAtPath:__directoryPath];
         if (directoryExists == NO) {
             [fileManager createDirectoryAtPath:__directoryPath withIntermediateDirectories:YES attributes:nil error:nil];
@@ -128,15 +128,15 @@ - (instancetype)initWithFormat:(FICImageFormat *)imageFormat {
 
         _lock = [[NSRecursiveLock alloc] init];
         _imageFormat = [imageFormat copy];
-        _imageFormatDictionary = [[imageFormat dictionaryRepresentation] retain];
+        _imageFormatDictionary = [imageFormat dictionaryRepresentation];
 
         _screenScale = [[UIScreen mainScreen] scale];
 
         int bytesPerPixel = 4;
         _imageRowLength = FICByteAlignForCoreAnimation([_imageFormat pixelSize].width * bytesPerPixel);
         _imageLength = _imageRowLength * (NSInteger)[_imageFormat pixelSize].height;
 
-        _chunkDictionary = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, NULL, NULL); // Non-retained keys and values
+        _chunkMapTable = [NSMapTable mapTableWithKeyOptions:NSMapTableStrongMemory valueOptions:NSMapTableWeakMemory];
 
         _indexMap = [[NSMutableDictionary alloc] init];
         _occupiedIndexes = [[NSMutableIndexSet alloc] init];
@@ -176,8 +176,7 @@ - (instancetype)initWithFormat:(FICImageFormat *)imageFormat {
             // If something goes wrong and we can't open the image table file, then we have no choice but to release and nil self.
             NSString *message = [NSString stringWithFormat:@"*** FIC Error: %s could not open the image table file at path %@. The image table was not created.", __PRETTY_FUNCTION__, _filePath];
             [[FICImageCache sharedImageCache] _logMessage:message];
-            
-            [self release];
+
             self = nil;
         }    
     }
@@ -190,54 +189,32 @@ - (instancetype)init {
 }
 
 - (void)dealloc {
-    [_imageFormat release];
-    [_filePath release];
-    
-    CFRelease(_chunkDictionary);
-    
-    [_indexMap release];
-    [_occupiedIndexes release];
-    [_MRUEntries release];
-    [_sourceImageMap release];
-    [_imageFormatDictionary release];
-    [_recentChunks release];
-    
     if (_fileDescriptor >= 0) {
         close(_fileDescriptor);
     }
-    
-    [_lock release];
-    
-    [super dealloc];
 }
 
 #pragma mark - Working with Chunks
 
 - (FICImageTableChunk *)_cachedChunkAtIndex:(NSInteger)index {
-    return (FICImageTableChunk *)CFDictionaryGetValue(_chunkDictionary, (const void *)index);
+    FICImageTableChunk *cachedChunk = [_chunkMapTable objectForKey:@(index)];
+    
+    return cachedChunk;
 }
 
 - (void)_setChunk:(FICImageTableChunk *)chunk index:(NSInteger)index {
     if (chunk != nil) {
-        CFDictionarySetValue(_chunkDictionary, (const void *)index, (const void *)chunk);
+        [_chunkMapTable setObject:chunk forKey:@(index)];
     } else {
-        CFDictionaryRemoveValue(_chunkDictionary, (const void *)index);
+        [_chunkMapTable removeObjectForKey:@(index)];
     }
 }
 
-- (void)_cleanupRecentChunks {
-    [_lock lock];
-    
-    [_recentChunks removeAllObjects];
-    
-    [_lock unlock];
-}
-
 - (FICImageTableChunk *)_chunkAtIndex:(NSInteger)index {
     FICImageTableChunk *chunk = nil;
 
     if (index < _chunkCount) {
-        chunk = [[self _cachedChunkAtIndex:index] retain];
+        chunk = [self _cachedChunkAtIndex:index];
 
         if (chunk == nil) {
             size_t chunkLength = _chunkLength;        
@@ -246,7 +223,7 @@ - (FICImageTableChunk *)_chunkAtIndex:(NSInteger)index {
                 chunkLength = _fileLength - chunkOffset;
             }
 
-            chunk = [[FICImageTableChunk alloc] initWithImageTable:self fileDescriptor:_fileDescriptor index:index length:chunkLength];
+            chunk = [[FICImageTableChunk alloc] initWithFileDescriptor:_fileDescriptor index:index length:chunkLength];
             [self _setChunk:chunk index:index];
         }
 
@@ -260,15 +237,7 @@ - (FICImageTableChunk *)_chunkAtIndex:(NSInteger)index {
         }
     }
 
-    return [chunk autorelease];
-}
-
-- (void)_chunkWillBeDeallocated:(FICImageTableChunk *)chunk {
-    [_lock lock];
-    
-    [self _setChunk:nil index:[chunk index]];
-    
-    [_lock unlock];
+    return chunk;
 }
 
 #pragma mark - Storing, Retrieving, and Deleting Entries
@@ -351,11 +320,9 @@ - (UIImage *)newImageForEntityUUID:(NSString *)entityUUID sourceImageUUID:(NSStr
             } else {
                 [self _entryWasAccessedWithEntityUUID:entityUUID];
 
-                [entryData retain]; // Released by _FICReleaseImageData
-                
                 // Create CGImageRef whose backing store *is* the mapped image table entry. We avoid a memcpy this way.
                 CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
-                CGDataProviderRef dataProvider = CGDataProviderCreateWithData((void *)entryData, [entryData bytes], [entryData imageLength], _FICReleaseImageData);
+                CGDataProviderRef dataProvider = CGDataProviderCreateWithData((__bridge_retained void *)entryData, [entryData bytes], [entryData imageLength], _FICReleaseImageData);
 
                 CGSize pixelSize = [_imageFormat pixelSize];
                 CGBitmapInfo bitmapInfo;
@@ -386,8 +353,7 @@ - (UIImage *)newImageForEntityUUID:(NSString *)entityUUID sourceImageUUID:(NSStr
 }
 
 static void _FICReleaseImageData(void *info, const void *data, size_t size) {
-    FICImageTableEntry *entryData = (FICImageTableEntry *)info;
-    [entryData release];
+    CFRelease(info);
 }
 
 - (void)deleteEntryForEntityUUID:(NSString *)entityUUID {
@@ -452,7 +418,7 @@ - (void)_setEntryCount:(NSInteger)entryCount {
         } else {
             _fileLength = fileLength;
             _entryCount = entryCount;
-            _chunkCount = (_entryCount + _entriesPerChunk - 1) / _entriesPerChunk;
+            _chunkCount = _entriesPerChunk > 0 ? ((_entryCount + _entriesPerChunk - 1) / _entriesPerChunk) : 0;
         }
     }
 }
@@ -478,7 +444,7 @@ - (FICImageTableEntry *)_entryDataAtIndex:(NSInteger)index {
 
     [_lock unlock];
 
-    return [entryData autorelease];
+    return entryData;
 }
 
 - (NSInteger)_nextEntryIndex {
@@ -489,7 +455,6 @@ - (NSInteger)_nextEntryIndex {
     if (index == NSNotFound) {
         index = _entryCount;
     }
-    [unoccupiedIndexes release];
 
     if (index >= [_imageFormat maximumCount] && [_MRUEntries count]) {
         // Evict the oldest/least-recently accessed entry here
@@ -533,10 +498,8 @@ - (void)_entryWasAccessedWithEntityUUID:(NSString *)entityUUID {
     if (index == NSNotFound) {
         [_MRUEntries insertObject:entityUUID atIndex:0];
     } else if (index != 0) {
-        [entityUUID retain];
         [_MRUEntries removeObjectAtIndex:index];
         [_MRUEntries insertObject:entityUUID atIndex:0];
-        [entityUUID release];
     }
 }
 

FastImageCache/FICImageTableChunk.h

@@ -42,8 +42,6 @@
 
 /**
  Initializes a new image table chunk.
- 
- @param imageTable The image table to create a chunk from.
 
  @param fileDescriptor The image table's file descriptor to map from.
  
@@ -53,6 +51,6 @@
  
  @return A new image table chunk.
  */
-- (instancetype)initWithImageTable:(FICImageTable *)imageTable fileDescriptor:(int)fileDescriptor index:(NSInteger)index length:(size_t)length;
+- (instancetype)initWithFileDescriptor:(int)fileDescriptor index:(NSInteger)index length:(size_t)length;
 
 @end