Merge pull request #902 from naithar/defer-usage

Author: swift-ci

Foundation/NSKeyedArchiver.swift

@@ -159,13 +159,13 @@ open class NSKeyedArchiver : NSCoder {
             return false
         }
 
+        defer { CFWriteStreamClose(writeStream) }
+        
         let keyedArchiver = NSKeyedArchiver(output: writeStream)
 
         keyedArchiver.encode(rootObject, forKey: NSKeyedArchiveRootObjectKey)
         keyedArchiver.finishEncoding()
         finishedEncoding = keyedArchiver._flags.contains(ArchiverFlags.finishedEncoding)
-
-        CFWriteStreamClose(writeStream)
 
         return finishedEncoding
     }

Foundation/NSKeyedUnarchiver.swift

@@ -74,15 +74,15 @@ open class NSKeyedUnarchiver : NSCoder {
             return nil
         }
 
+        defer { CFReadStreamClose(readStream) }
+        
         let keyedUnarchiver = NSKeyedUnarchiver(stream: Stream.stream(readStream))
         do {
             try root = keyedUnarchiver.decodeTopLevelObject(forKey: NSKeyedArchiveRootObjectKey)
             keyedUnarchiver.finishDecoding()
         } catch {
         }
 
-        CFReadStreamClose(readStream)
-        
         return root
     }
 

Foundation/NSXMLParser.swift

@@ -559,9 +559,12 @@ open class XMLParser : NSObject {
     internal func parseFromStream() -> Bool {
         var result = true
         XMLParser.setCurrentParser(self)
+        defer { XMLParser.setCurrentParser(nil) }
         if let stream = _stream {
             stream.open()
+            defer { stream.close() }
             let buffer = malloc(_chunkSize)!.bindMemory(to: UInt8.self, capacity: _chunkSize)
+            defer { free(buffer) }
             var len = stream.read(buffer, maxLength: _chunkSize)
             if len != -1 {
                 while len > 0 {
@@ -572,10 +575,9 @@ open class XMLParser : NSObject {
             } else {
                 result = false
             }
-            free(buffer)
-            stream.close()
         } else if let data = _data {
             let buffer = malloc(_chunkSize)!.bindMemory(to: UInt8.self, capacity: _chunkSize)
+            defer { free(buffer) }
             var range = NSMakeRange(0, min(_chunkSize, data.count))
             while result {
                 let chunk = data.withUnsafeBytes { (buffer: UnsafePointer<UInt8>) -> Data in
@@ -588,11 +590,9 @@ open class XMLParser : NSObject {
                 }
                 range = NSMakeRange(range.location + range.length, min(_chunkSize, data.count - (range.location + range.length)))
             }
-            free(buffer)
         } else {
             result = false
         }
-        XMLParser.setCurrentParser(nil)
         return result
     }