Begin implementation of NSURLSessionDownloadTask

Headers/Foundation/NSURLSession.h

@@ -24,6 +24,7 @@
 @class NSURLResponse;
 @class NSURLSessionConfiguration;
 @class NSURLSessionDataTask;
+@class NSURLSessionDownloadTask;
 
 
 /**
@@ -110,6 +111,12 @@ GS_EXPORT_CLASS
 /* Creates a data task to retrieve the contents of the given URL. */
 - (NSURLSessionDataTask*) dataTaskWithURL: (NSURL*)url;
 
+/* Creates a download task with the given request. */
+- (NSURLSessionDownloadTask *) downloadTaskWithRequest: (NSURLRequest *)request;
+
+/* Creates a download task to download the contents of the given URL. */
+- (NSURLSessionDownloadTask *) downloadTaskWithURL: (NSURL *)url;
+
 @end
 
 typedef NS_ENUM(NSUInteger, NSURLSessionTaskState) {
@@ -430,6 +437,37 @@ didReceiveChallenge: (NSURLAuthenticationChallenge*)challenge
 
 @end
 
+@protocol NSURLSessionDownloadDelegate <NSURLSessionTaskDelegate>
+
+/* Sent when a download task that has completed a download.  The delegate should 
+ * copy or move the file at the given location to a new location as it will be 
+ * removed when the delegate message returns. URLSession:task:didCompleteWithError: will
+ * still be called.
+ */
+- (void)         URLSession: (NSURLSession *)session
+               downloadTask: (NSURLSessionDownloadTask *)downloadTask
+  didFinishDownloadingToURL: (NSURL *)location;
+
+@optional
+/* Sent periodically to notify the delegate of download progress. */
+- (void)         URLSession: (NSURLSession *)session
+               downloadTask: (NSURLSessionDownloadTask *)downloadTask
+               didWriteData: (int64_t)bytesWritten
+          totalBytesWritten: (int64_t)totalBytesWritten
+  totalBytesExpectedToWrite: (int64_t)totalBytesExpectedToWrite;
+
+/* Sent when a download has been resumed. If a download failed with an
+ * error, the -userInfo dictionary of the error will contain an
+ * NSURLSessionDownloadTaskResumeData key, whose value is the resume
+ * data. 
+ */
+- (void)  URLSession: (NSURLSession *)session
+        downloadTask: (NSURLSessionDownloadTask *)downloadTask
+   didResumeAtOffset: (int64_t)fileOffset
+  expectedTotalBytes: (int64_t)expectedTotalBytes;
+
+@end
+
 #endif
 #endif
 #endif

Source/GSNativeProtocol.m

@@ -9,6 +9,7 @@
 #import "Foundation/NSURL.h"
 #import "Foundation/NSURLError.h"
 #import "Foundation/NSURLSession.h"
+#import "Foundation/NSFileHandle.h"
 
 
 static BOOL isEasyHandlePaused(GSNativeProtocolInternalState state) 
@@ -97,6 +98,8 @@ static BOOL isEasyHandleAddedToMultiHandle(GSNativeProtocolInternalState state)
 
 - (void) setError: (NSError*)error;
 
+- (void) setCountOfBytesReceived: (int64_t)count;
+
 @end
 
 @implementation NSURLSessionTask (Internal)
@@ -138,6 +141,11 @@ static BOOL isEasyHandleAddedToMultiHandle(GSNativeProtocolInternalState state)
   ASSIGN(_error, error);
 }
 
+- (void) setCountOfBytesReceived: (int64_t)count
+{
+  _countOfBytesReceived = count;
+}
+
 @end
 
 @implementation GSCompletionAction
@@ -493,13 +501,16 @@ static BOOL isEasyHandleAddedToMultiHandle(GSNativeProtocolInternalState state)
 
 - (void) notifyDelegateAboutReceivedData: (NSData*)data
 {
-  NSURLSessionTask              *task;
-  id<NSURLSessionDelegate>      delegate;
+  NSURLSession                 *session;
+  NSURLSessionTask             *task;
+  id<NSURLSessionDelegate>     delegate;
 
   task = [self task];
-
   NSAssert(nil != task, @"Cannot notify");
 
+  session = [task session];
+  NSAssert(nil != session, @"Missing session");
+
   delegate = [[task session] delegate];
   if (nil != delegate
     && [task isKindOfClass: [NSURLSessionDataTask class]]
@@ -507,10 +518,7 @@ static BOOL isEasyHandleAddedToMultiHandle(GSNativeProtocolInternalState state)
     {
       id<NSURLSessionDataDelegate> dataDelegate;
       NSURLSessionDataTask         *dataTask;
-      NSURLSession                 *session;
-
-      session = [task session];
-      NSAssert(nil != session, @"Missing session");
+      
       dataDelegate = (id<NSURLSessionDataDelegate>)delegate;
       dataTask = (NSURLSessionDataTask*)task;
       [[session delegateQueue] addOperationWithBlock:
@@ -520,6 +528,40 @@ static BOOL isEasyHandleAddedToMultiHandle(GSNativeProtocolInternalState state)
                     didReceiveData: data];
         }];
     }
+  /* Don't check whether delegate respondsToSelector.
+   * This delegate is optional. */
+  if (nil != delegate
+    && [task isKindOfClass: [NSURLSessionDownloadTask class]])
+    {
+      id<NSURLSessionDownloadDelegate> downloadDelegate;
+      NSURLSessionDownloadTask *downloadTask;
+      GSDataDrain *dataDrain;
+      NSFileHandle *fileHandle;
+
+      downloadDelegate = (id<NSURLSessionDownloadDelegate>)delegate;
+      downloadTask = (NSURLSessionDownloadTask*)task;
+      dataDrain = [_transferState bodyDataDrain];
+
+      /* Write to file. GSDataDrain opens the fileHandle. */
+      fileHandle = [dataDrain fileHandle];
+      [fileHandle seekToEndOfFile];
+      [fileHandle writeData: data];
+
+      if ([delegate respondsToSelector: @selector
+          (URLSession:downloadTask:didWriteData:totalBytesWritten:totalBytesExpectedToWrite:)])
+        {
+          /* Calculate received data length */
+          [task setCountOfBytesReceived: (int64_t)[data length] + [task countOfBytesReceived]];
+          [[session delegateQueue] addOperationWithBlock:
+          ^{
+            [downloadDelegate URLSession: session 
+                            downloadTask: downloadTask 
+                            didWriteData: (int64_t)[data length]
+                       totalBytesWritten: [task countOfBytesReceived]
+               totalBytesExpectedToWrite: [task countOfBytesExpectedToReceive]];
+          }];
+        }
+    }
 }
 
 - (void) notifyDelegateAboutUploadedDataCount: (int64_t)count 

Source/GSTransferState.m

@@ -10,6 +10,9 @@
 #import "Foundation/NSURLError.h"
 #import "Foundation/NSURLResponse.h"
 #import "Foundation/NSURLSession.h"
+#import "Foundation/NSUUID.h"
+#import "Foundation/NSFileManager.h"
+#import "Foundation/NSPathUtilities.h"
 
 #define GS_DELIMITERS_CR 0x0d
 #define GS_DELIMITERS_LR 0x0a
@@ -277,6 +280,25 @@
 
 - (NSURL*) fileURL
 {
+  /* Generate a random fileURL if fileURL is not initialized.
+   * It would be nice to have this implemented in an initializer. */
+  if (!_fileURL)
+    {
+      NSUUID *randomUUID;
+      NSString *fileName;
+      NSURL *tempURL;
+      
+      randomUUID = [NSUUID UUID];
+      fileName = [[randomUUID UUIDString] stringByAppendingPathExtension: @"tmp"];
+      tempURL = [NSURL fileURLWithPath: NSTemporaryDirectory()];
+
+      _fileURL = [NSURL fileURLWithPath: fileName relativeToURL: tempURL];
+
+      RELEASE(randomUUID);
+      RELEASE(fileName);
+      RELEASE(tempURL);
+    }
+
   return _fileURL;
 }
 
@@ -287,6 +309,17 @@
 
 - (NSFileHandle*) fileHandle
 {
+  /* Create temporary file and open a fileHandle for writing. */
+  if (!_fileHandle)
+    {
+      NSFileManager *file = [NSFileManager defaultManager];
+      [file createFileAtPath: [[self fileURL] relativePath] contents: nil attributes: nil];
+
+      _fileHandle = [NSFileHandle fileHandleForWritingToURL: [self fileURL] error: NULL];
+
+      RELEASE(file);
+    }
+
   return _fileHandle;
 }
 

Source/NSURLSession.m

@@ -284,6 +284,34 @@ static int nextSessionIdentifier()
   return [self dataTaskWithRequest: request];
 }
 
+- (NSURLSessionDownloadTask *) downloadTaskWithRequest: (NSURLRequest *)request
+{
+  NSURLSessionDownloadTask  *task;
+
+  if (_invalidated)
+    {
+      return nil;
+    }
+
+  task = [[NSURLSessionDownloadTask alloc] initWithSession: self 
+                                                   request: request 
+                                            taskIdentifier: _nextTaskIdentifier++];
+
+  [self addTask: task];
+
+  return AUTORELEASE(task);
+}
+
+- (NSURLSessionDownloadTask *) downloadTaskWithURL: (NSURL *)url
+{
+  NSMutableURLRequest *request;
+  
+  request = [NSMutableURLRequest requestWithURL: url];
+  [request setHTTPMethod: @"GET"];
+
+  return [self downloadTaskWithRequest: request];
+}
+
 - (void) addTask: (NSURLSessionTask*)task
 {
   [_taskRegistry addTask: task];
@@ -632,7 +660,7 @@ static int nextSessionIdentifier()
 
 @implementation NSURLSessionTask
 {
-  NSURLSession                   *_session; /* not retained */
+  NSURLSession                   *_session;
   NSLock                         *_protocolLock;
   NSURLSessionTaskProtocolState  _protocolState;
   NSURLProtocol                  *_protocol;
@@ -653,7 +681,7 @@ static int nextSessionIdentifier()
       NSData		*data;
       NSInputStream	*stream;
 
-      _session = session;
+      ASSIGN(_session, session);
       ASSIGN(_originalRequest, request);
       ASSIGN(_currentRequest, request);
       if ([(data = [request HTTPBody]) length] > 0)
@@ -694,6 +722,7 @@ static int nextSessionIdentifier()
 
 - (void) dealloc
 {
+  DESTROY(_session);
   DESTROY(_originalRequest);
   DESTROY(_currentRequest);
   DESTROY(_response);
@@ -1083,6 +1112,10 @@ static int nextSessionIdentifier()
 
 @end
 
+@implementation NSURLSessionDownloadTask
+
+@end
+
 @implementation NSURLSessionConfiguration
 
 static NSURLSessionConfiguration	*def = nil;