Rename CK classes to AS classes

AsyncDisplayKit/TextKit/ASTextKitContext.mm

@@ -0,0 +1,60 @@
+/*
+ *  Copyright (c) 2014-present, Facebook, Inc.
+ *  All rights reserved.
+ *
+ *  This source code is licensed under the BSD-style license found in the
+ *  LICENSE file in the root directory of this source tree. An additional grant
+ *  of patent rights can be found in the PATENTS file in the same directory.
+ *
+ */
+
+#import <mutex>
+
+#import "ASTextKitContext.h"
+
+@implementation ASTextKitContext
+{
+  // All TextKit operations (even non-mutative ones) must be executed serially.
+  std::mutex _textKitMutex;
+
+  NSLayoutManager *_layoutManager;
+  NSTextStorage *_textStorage;
+  NSTextContainer *_textContainer;
+}
+
+- (instancetype)initWithAttributedString:(NSAttributedString *)attributedString
+                           lineBreakMode:(NSLineBreakMode)lineBreakMode
+                    maximumNumberOfLines:(NSUInteger)maximumNumberOfLines
+                          exclusionPaths:(NSArray *)exclusionPaths
+                         constrainedSize:(CGSize)constrainedSize
+                    layoutManagerFactory:(NSLayoutManager*(*)(void))layoutManagerFactory
+{
+  if (self = [super init]) {
+    // Concurrently initialising TextKit components crashes (rdar://18448377) so we use a global lock.
+    static std::mutex __static_mutex;
+    std::lock_guard<std::mutex> l(__static_mutex);
+    // Create the TextKit component stack with our default configuration.
+    _textStorage = (attributedString ? [[NSTextStorage alloc] initWithAttributedString:attributedString] : [[NSTextStorage alloc] init]);
+    _layoutManager = layoutManagerFactory ? layoutManagerFactory() : [[NSLayoutManager alloc] init];
+    _layoutManager.usesFontLeading = NO;
+    [_textStorage addLayoutManager:_layoutManager];
+    _textContainer = [[NSTextContainer alloc] initWithSize:constrainedSize];
+    // We want the text laid out up to the very edges of the container.
+    _textContainer.lineFragmentPadding = 0;
+    _textContainer.lineBreakMode = lineBreakMode;
+    _textContainer.maximumNumberOfLines = maximumNumberOfLines;
+    _textContainer.exclusionPaths = exclusionPaths;
+    [_layoutManager addTextContainer:_textContainer];
+  }
+  return self;
+}
+
+- (void)performBlockWithLockedTextKitComponents:(void (^)(NSLayoutManager *,
+                                                          NSTextStorage *,
+                                                          NSTextContainer *))block
+{
+  std::lock_guard<std::mutex> l(_textKitMutex);
+  block(_layoutManager, _textStorage, _textContainer);
+}
+
+@end