iOS Cronet: Put cap on the buffer size passed to onReadCompleted delegate

components/cronet/ios/test/cronet_http_test.mm

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import <Cronet/Cronet.h>
 #import <Foundation/Foundation.h>
 
 #include <stdint.h>
 
 #include "base/logging.h"
@@ skipping 15 matching lines @@
                                    NSURLSessionTaskDelegate>
 
 // Completion semaphore for this TestDelegate. When the request this delegate is
 // attached to finishes (either successfully or with an error), this delegate
 // signals this semaphore.
 @property(assign, atomic) dispatch_semaphore_t semaphore;
 
 // Error the request this delegate is attached to failed with, if any.
 @property(retain, atomic) NSError* error;
 
+// Contains total amount of received data.
+@property(readonly) long totalBytesReceived;
+
 @end
 
 @implementation TestDelegate
+
 @synthesize semaphore = _semaphore;
 @synthesize error = _error;
+@synthesize totalBytesReceived = _totalBytesReceived;
 
 NSMutableArray<NSData*>* _responseData;
 
 - (id)init {
   if (self = [super init]) {
     _semaphore = dispatch_semaphore_create(0);
   }
   return self;
 }
 
 - (void)dealloc {
   dispatch_release(_semaphore);
   [_error release];
   _error = nil;
   [super dealloc];
 }
 
 - (void)reset {
   [_responseData dealloc];
   _responseData = nil;
   _error = nil;
+  _totalBytesReceived = 0;
 }
 
 - (NSString*)responseBody {
   if (_responseData == nil) {
     return nil;
   }
   NSMutableString* body = [NSMutableString string];
   for (NSData* data in _responseData) {
     [body appendString:[[NSString alloc] initWithData:data
                                              encoding:NSUTF8StringEncoding]];
@@ skipping 27 matching lines @@
               dataTask:(NSURLSessionDataTask*)dataTask
     didReceiveResponse:(NSURLResponse*)response
      completionHandler:(void (^)(NSURLSessionResponseDisposition disposition))
                            completionHandler {
   completionHandler(NSURLSessionResponseAllow);
 }
 
 - (void)URLSession:(NSURLSession*)session
           dataTask:(NSURLSessionDataTask*)dataTask
     didReceiveData:(NSData*)data {
+  _totalBytesReceived += [data length];
   if (_responseData == nil) {
     _responseData = [[NSMutableArray alloc] init];
   }
   [_responseData addObject:data];
 }
 
 - (void)URLSession:(NSURLSession*)session
              dataTask:(NSURLSessionDataTask*)dataTask
     willCacheResponse:(NSCachedURLResponse*)proposedResponse
     completionHandler:
@@ skipping 99 matching lines @@
       return YES;
     }];
     NSDate* start = [NSDate date];
     StartDataTaskAndWaitForCompletion(task);
     NSTimeInterval elapsed = -[start timeIntervalSinceNow];
     elapsed_avg += elapsed;
     if (elapsed > elapsed_max)
       elapsed_max = elapsed;
     EXPECT_TRUE(block_used);
     EXPECT_EQ(nil, [delegate_ error]);
+    EXPECT_EQ(size, [delegate_ totalBytesReceived]);
   }
   // Release the response buffer.
   TestServer::ReleaseBigDataURL();
   LOG(INFO) << "Elapsed Average:" << elapsed_avg * 1000 / iterations
             << "ms Max:" << elapsed_max * 1000 << "ms";
 }
 
 TEST_F(HttpTest, GetGlobalMetricsDeltas) {
   NSData* delta1 = [Cronet getGlobalMetricsDeltas];
 
@@ skipping 224 matching lines @@
   [Cronet setRequestFilterBlock:^(NSURLRequest* request) {
     EXPECT_TRUE(false) << "Block should not be called for unsupported requests";
     return YES;
   }];
   StartDataTaskAndWaitForCompletion(task);
   EXPECT_EQ(nil, [delegate_ error]);
   EXPECT_TRUE([[delegate_ responseBody] containsString:testString]);
 }
 
 }  // namespace cronet