src/content/browser/download/download_resource_handler.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/download/download_resource_handler.h"
   6
   7 #include <string>
   8
   9 #include "base/bind.h"
  10 #include "base/logging.h"
  11 #include "base/message_loop/message_loop_proxy.h"
  12 #include "base/metrics/histogram.h"
  13 #include "base/metrics/stats_counters.h"
  14 #include "base/strings/stringprintf.h"
  15 #include "content/browser/byte_stream.h"
  16 #include "content/browser/download/download_create_info.h"
  17 #include "content/browser/download/download_interrupt_reasons_impl.h"
  18 #include "content/browser/download/download_manager_impl.h"
  19 #include "content/browser/download/download_request_handle.h"
  20 #include "content/browser/download/download_stats.h"
  21 #include "content/browser/loader/resource_dispatcher_host_impl.h"
  22 #include "content/browser/loader/resource_request_info_impl.h"
  23 #include "content/public/browser/browser_thread.h"
  24 #include "content/public/browser/download_interrupt_reasons.h"
  25 #include "content/public/browser/download_item.h"
  26 #include "content/public/browser/download_manager_delegate.h"
  27 #include "content/public/common/resource_response.h"
  28 #include "net/base/io_buffer.h"
  29 #include "net/base/net_errors.h"
  30 #include "net/http/http_response_headers.h"
  31 #include "net/http/http_status_code.h"
  32 #include "net/url_request/url_request_context.h"
  33
  34 namespace content {
  35 namespace {
  36
  37 void CallStartedCBOnUIThread(
  38     const DownloadUrlParameters::OnStartedCallback& started_cb,
  39     DownloadItem* item,
  40     DownloadInterruptReason interrupt_reason) {
  41   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  42
  43   if (started_cb.is_null())
  44     return;
  45   started_cb.Run(item, interrupt_reason);
  46 }
  47
  48 // Static function in order to prevent any accidental accesses to
  49 // DownloadResourceHandler members from the UI thread.
  50 static void StartOnUIThread(
  51     scoped_ptr<DownloadCreateInfo> info,
  52     scoped_ptr<ByteStreamReader> stream,
  53     const DownloadUrlParameters::OnStartedCallback& started_cb) {
  54   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  55
  56   DownloadManager* download_manager = info->request_handle.GetDownloadManager();
  57   if (!download_manager) {
  58     // NULL in unittests or if the page closed right after starting the
  59     // download.
  60     if (!started_cb.is_null())
  61       started_cb.Run(NULL, DOWNLOAD_INTERRUPT_REASON_USER_CANCELED);
  62     return;
  63   }
  64
  65   download_manager->StartDownload(info.Pass(), stream.Pass(), started_cb);
  66 }
  67
  68 }  // namespace
  69
  70 const int DownloadResourceHandler::kDownloadByteStreamSize = 100 * 1024;
  71
  72 DownloadResourceHandler::DownloadResourceHandler(
  73     uint32 id,
  74     net::URLRequest* request,
  75     const DownloadUrlParameters::OnStartedCallback& started_cb,
  76     scoped_ptr<DownloadSaveInfo> save_info)
  77     : ResourceHandler(request),
  78       download_id_(id),
  79       started_cb_(started_cb),
  80       save_info_(save_info.Pass()),
  81       last_buffer_size_(0),
  82       bytes_read_(0),
  83       pause_count_(0),
  84       was_deferred_(false),
  85       on_response_started_called_(false) {
  86   RecordDownloadCount(UNTHROTTLED_COUNT);
  87 }
  88
  89 bool DownloadResourceHandler::OnUploadProgress(int request_id,
  90                                                uint64 position,
  91                                                uint64 size) {
  92   return true;
  93 }
  94
  95 bool DownloadResourceHandler::OnRequestRedirected(
  96     int request_id,
  97     const GURL& url,
  98     ResourceResponse* response,
  99     bool* defer) {
 100   // We treat a download as a main frame load, and thus update the policy URL
 101   // on redirects.
 102   request()->set_first_party_for_cookies(url);
 103   return true;
 104 }
 105
 106 // Send the download creation information to the download thread.
 107 bool DownloadResourceHandler::OnResponseStarted(
 108     int request_id,
 109     ResourceResponse* response,
 110     bool* defer) {
 111   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 112   // There can be only one (call)
 113   DCHECK(!on_response_started_called_);
 114   on_response_started_called_ = true;
 115
 116   VLOG(20) << __FUNCTION__ << "()" << DebugString()
 117            << " request_id = " << request_id;
 118   download_start_time_ = base::TimeTicks::Now();
 119
 120   // If it's a download, we don't want to poison the cache with it.
 121   request()->StopCaching();
 122
 123   // Lower priority as well, so downloads don't contend for resources
 124   // with main frames.
 125   request()->SetPriority(net::IDLE);
 126
 127   // If the content-length header is not present (or contains something other
 128   // than numbers), the incoming content_length is -1 (unknown size).
 129   // Set the content length to 0 to indicate unknown size to DownloadManager.
 130   int64 content_length =
 131       response->head.content_length > 0 ? response->head.content_length : 0;
 132
 133   const ResourceRequestInfoImpl* request_info = GetRequestInfo();
 134
 135   // Deleted in DownloadManager.
 136   scoped_ptr<DownloadCreateInfo> info(
 137       new DownloadCreateInfo(base::Time::Now(),
 138                              content_length,
 139                              request()->net_log(),
 140                              request_info->HasUserGesture(),
 141                              request_info->GetPageTransition(),
 142                              save_info_.Pass()));
 143
 144   // Create the ByteStream for sending data to the download sink.
 145   scoped_ptr<ByteStreamReader> stream_reader;
 146   CreateByteStream(
 147       base::MessageLoopProxy::current(),
 148       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE),
 149       kDownloadByteStreamSize, &stream_writer_, &stream_reader);
 150   stream_writer_->RegisterCallback(
 151       base::Bind(&DownloadResourceHandler::ResumeRequest, AsWeakPtr()));
 152
 153   info->download_id = download_id_;
 154   info->url_chain = request()->url_chain();
 155   info->referrer_url = GURL(request()->referrer());
 156   info->mime_type = response->head.mime_type;
 157   info->remote_address = request()->GetSocketAddress().host();
 158   request()->GetResponseHeaderByName("content-disposition",
 159                                      &info->content_disposition);
 160   RecordDownloadMimeType(info->mime_type);
 161   RecordDownloadContentDisposition(info->content_disposition);
 162
 163   info->request_handle =
 164       DownloadRequestHandle(AsWeakPtr(), request_info->GetChildID(),
 165                             request_info->GetRouteID(),
 166                             request_info->GetRequestID());
 167
 168   // Get the last modified time and etag.
 169   const net::HttpResponseHeaders* headers = request()->response_headers();
 170   if (headers) {
 171     if (headers->HasStrongValidators()) {
 172       // If we don't have strong validators as per RFC 2616 section 13.3.3, then
 173       // we neither store nor use them for range requests.
 174       if (!headers->EnumerateHeader(NULL, "Last-Modified",
 175                                     &info->last_modified))
 176         info->last_modified.clear();
 177       if (!headers->EnumerateHeader(NULL, "ETag", &info->etag))
 178         info->etag.clear();
 179     }
 180
 181     int status = headers->response_code();
 182     if (2 == status / 100  && status != net::HTTP_PARTIAL_CONTENT) {
 183       // Success & not range response; if we asked for a range, we didn't
 184       // get it--reset the file pointers to reflect that.
 185       info->save_info->offset = 0;
 186       info->save_info->hash_state = "";
 187     }
 188
 189     if (!headers->GetMimeType(&info->original_mime_type))
 190       info->original_mime_type.clear();
 191   }
 192
 193   BrowserThread::PostTask(
 194       BrowserThread::UI, FROM_HERE,
 195       base::Bind(&StartOnUIThread,
 196                  base::Passed(&info),
 197                  base::Passed(&stream_reader),
 198                  // Pass to StartOnUIThread so that variable
 199                  // access is always on IO thread but function
 200                  // is called on UI thread.
 201                  started_cb_));
 202   // Guaranteed to be called in StartOnUIThread
 203   started_cb_.Reset();
 204
 205   return true;
 206 }
 207
 208 void DownloadResourceHandler::CallStartedCB(
 209     DownloadItem* item,
 210     DownloadInterruptReason interrupt_reason) {
 211   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 212   if (started_cb_.is_null())
 213     return;
 214   BrowserThread::PostTask(
 215       BrowserThread::UI,
 216       FROM_HERE,
 217       base::Bind(
 218           &CallStartedCBOnUIThread, started_cb_, item, interrupt_reason));
 219   started_cb_.Reset();
 220 }
 221
 222 bool DownloadResourceHandler::OnWillStart(int request_id,
 223                                           const GURL& url,
 224                                           bool* defer) {
 225   return true;
 226 }
 227
 228 bool DownloadResourceHandler::OnBeforeNetworkStart(int request_id,
 229                                                    const GURL& url,
 230                                                    bool* defer) {
 231   return true;
 232 }
 233
 234 // Create a new buffer, which will be handed to the download thread for file
 235 // writing and deletion.
 236 bool DownloadResourceHandler::OnWillRead(int request_id,
 237                                          scoped_refptr<net::IOBuffer>* buf,
 238                                          int* buf_size,
 239                                          int min_size) {
 240   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 241   DCHECK(buf && buf_size);
 242   DCHECK(!read_buffer_.get());
 243
 244   *buf_size = min_size < 0 ? kReadBufSize : min_size;
 245   last_buffer_size_ = *buf_size;
 246   read_buffer_ = new net::IOBuffer(*buf_size);
 247   *buf = read_buffer_.get();
 248   return true;
 249 }
 250
 251 // Pass the buffer to the download file writer.
 252 bool DownloadResourceHandler::OnReadCompleted(int request_id, int bytes_read,
 253                                               bool* defer) {
 254   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 255   DCHECK(read_buffer_.get());
 256
 257   base::TimeTicks now(base::TimeTicks::Now());
 258   if (!last_read_time_.is_null()) {
 259     double seconds_since_last_read = (now - last_read_time_).InSecondsF();
 260     if (now == last_read_time_)
 261       // Use 1/10 ms as a "very small number" so that we avoid
 262       // divide-by-zero error and still record a very high potential bandwidth.
 263       seconds_since_last_read = 0.00001;
 264
 265     double actual_bandwidth = (bytes_read)/seconds_since_last_read;
 266     double potential_bandwidth = last_buffer_size_/seconds_since_last_read;
 267     RecordBandwidth(actual_bandwidth, potential_bandwidth);
 268   }
 269   last_read_time_ = now;
 270
 271   if (!bytes_read)
 272     return true;
 273   bytes_read_ += bytes_read;
 274   DCHECK(read_buffer_.get());
 275
 276   // Take the data ship it down the stream.  If the stream is full, pause the
 277   // request; the stream callback will resume it.
 278   if (!stream_writer_->Write(read_buffer_, bytes_read)) {
 279     PauseRequest();
 280     *defer = was_deferred_ = true;
 281     last_stream_pause_time_ = now;
 282   }
 283
 284   read_buffer_ = NULL;  // Drop our reference.
 285
 286   if (pause_count_ > 0)
 287     *defer = was_deferred_ = true;
 288
 289   return true;
 290 }
 291
 292 void DownloadResourceHandler::OnResponseCompleted(
 293     int request_id,
 294     const net::URLRequestStatus& status,
 295     const std::string& security_info,
 296     bool* defer) {
 297   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 298   int response_code = status.is_success() ? request()->GetResponseCode() : 0;
 299   VLOG(20) << __FUNCTION__ << "()" << DebugString()
 300            << " request_id = " << request_id
 301            << " status.status() = " << status.status()
 302            << " status.error() = " << status.error()
 303            << " response_code = " << response_code;
 304
 305   net::Error error_code = net::OK;
 306   if (status.status() == net::URLRequestStatus::FAILED ||
 307       // Note cancels as failures too.
 308       status.status() == net::URLRequestStatus::CANCELED) {
 309     error_code = static_cast<net::Error>(status.error());  // Normal case.
 310     // Make sure that at least the fact of failure comes through.
 311     if (error_code == net::OK)
 312       error_code = net::ERR_FAILED;
 313   }
 314
 315   // ERR_CONTENT_LENGTH_MISMATCH and ERR_INCOMPLETE_CHUNKED_ENCODING are
 316   // allowed since a number of servers in the wild close the connection too
 317   // early by mistake. Other browsers - IE9, Firefox 11.0, and Safari 5.1.4 -
 318   // treat downloads as complete in both cases, so we follow their lead.
 319   if (error_code == net::ERR_CONTENT_LENGTH_MISMATCH ||
 320       error_code == net::ERR_INCOMPLETE_CHUNKED_ENCODING) {
 321     error_code = net::OK;
 322   }
 323   DownloadInterruptReason reason =
 324       ConvertNetErrorToInterruptReason(
 325         error_code, DOWNLOAD_INTERRUPT_FROM_NETWORK);
 326
 327   if (status.status() == net::URLRequestStatus::CANCELED &&
 328       status.error() == net::ERR_ABORTED) {
 329     // CANCELED + ERR_ABORTED == something outside of the network
 330     // stack cancelled the request.  There aren't that many things that
 331     // could do this to a download request (whose lifetime is separated from
 332     // the tab from which it came).  We map this to USER_CANCELLED as the
 333     // case we know about (system suspend because of laptop close) corresponds
 334     // to a user action.
 335     // TODO(ahendrickson) -- Find a better set of codes to use here, as
 336     // CANCELED/ERR_ABORTED can occur for reasons other than user cancel.
 337     reason = DOWNLOAD_INTERRUPT_REASON_USER_CANCELED;
 338   }
 339
 340   if (status.is_success() &&
 341       reason == DOWNLOAD_INTERRUPT_REASON_NONE &&
 342       request()->response_headers()) {
 343     // Handle server's response codes.
 344     switch(response_code) {
 345       case -1:                          // Non-HTTP request.
 346       case net::HTTP_OK:
 347       case net::HTTP_CREATED:
 348       case net::HTTP_ACCEPTED:
 349       case net::HTTP_NON_AUTHORITATIVE_INFORMATION:
 350       case net::HTTP_RESET_CONTENT:
 351       case net::HTTP_PARTIAL_CONTENT:
 352         // Expected successful codes.
 353         break;
 354       case net::HTTP_NO_CONTENT:
 355       case net::HTTP_NOT_FOUND:
 356         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_BAD_CONTENT;
 357         break;
 358       case net::HTTP_PRECONDITION_FAILED:
 359         // Failed our 'If-Unmodified-Since' or 'If-Match'; see
 360         // download_manager_impl.cc BeginDownload()
 361         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_PRECONDITION;
 362         break;
 363       case net::HTTP_REQUESTED_RANGE_NOT_SATISFIABLE:
 364         // Retry by downloading from the start automatically:
 365         // If we haven't received data when we get this error, we won't.
 366         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_NO_RANGE;
 367         break;
 368       default:    // All other errors.
 369         // Redirection and informational codes should have been handled earlier
 370         // in the stack.
 371         DCHECK_NE(3, response_code / 100);
 372         DCHECK_NE(1, response_code / 100);
 373         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_FAILED;
 374         break;
 375     }
 376   }
 377
 378   std::string accept_ranges;
 379   bool has_strong_validators = false;
 380   if (request()->response_headers()) {
 381     request()->response_headers()->EnumerateHeader(
 382         NULL, "Accept-Ranges", &accept_ranges);
 383     has_strong_validators =
 384         request()->response_headers()->HasStrongValidators();
 385   }
 386   RecordAcceptsRanges(accept_ranges, bytes_read_, has_strong_validators);
 387   RecordNetworkBlockage(base::TimeTicks::Now() - download_start_time_,
 388                         total_pause_time_);
 389
 390   CallStartedCB(NULL, reason);
 391
 392   // Send the info down the stream.  Conditional is in case we get
 393   // OnResponseCompleted without OnResponseStarted.
 394   if (stream_writer_)
 395     stream_writer_->Close(reason);
 396
 397   // If the error mapped to something unknown, record it so that
 398   // we can drill down.
 399   if (reason == DOWNLOAD_INTERRUPT_REASON_NETWORK_FAILED) {
 400     UMA_HISTOGRAM_CUSTOM_ENUMERATION("Download.MapErrorNetworkFailed",
 401                                      std::abs(status.error()),
 402                                      net::GetAllErrorCodesForUma());
 403   }
 404
 405   stream_writer_.reset();  // We no longer need the stream.
 406   read_buffer_ = NULL;
 407 }
 408
 409 void DownloadResourceHandler::OnDataDownloaded(
 410     int request_id,
 411     int bytes_downloaded) {
 412   NOTREACHED();
 413 }
 414
 415 void DownloadResourceHandler::PauseRequest() {
 416   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 417
 418   ++pause_count_;
 419 }
 420
 421 void DownloadResourceHandler::ResumeRequest() {
 422   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 423   DCHECK_LT(0, pause_count_);
 424
 425   --pause_count_;
 426
 427   if (!was_deferred_)
 428     return;
 429   if (pause_count_ > 0)
 430     return;
 431
 432   was_deferred_ = false;
 433   if (!last_stream_pause_time_.is_null()) {
 434     total_pause_time_ += (base::TimeTicks::Now() - last_stream_pause_time_);
 435     last_stream_pause_time_ = base::TimeTicks();
 436   }
 437
 438   controller()->Resume();
 439 }
 440
 441 void DownloadResourceHandler::CancelRequest() {
 442   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 443
 444   const ResourceRequestInfo* info = GetRequestInfo();
 445   ResourceDispatcherHostImpl::Get()->CancelRequest(
 446       info->GetChildID(),
 447       info->GetRequestID());
 448   // This object has been deleted.
 449 }
 450
 451 std::string DownloadResourceHandler::DebugString() const {
 452   const ResourceRequestInfo* info = GetRequestInfo();
 453   return base::StringPrintf("{"
 454                             " url_ = " "\"%s\""
 455                             " info = {"
 456                             " child_id = " "%d"
 457                             " request_id = " "%d"
 458                             " route_id = " "%d"
 459                             " }"
 460                             " }",
 461                             request() ?
 462                                 request()->url().spec().c_str() :
 463                                 "<NULL request>",
 464                             info->GetChildID(),
 465                             info->GetRequestID(),
 466                             info->GetRouteID());
 467 }
 468
 469 DownloadResourceHandler::~DownloadResourceHandler() {
 470   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 471
 472   // This won't do anything if the callback was called before.
 473   // If it goes through, it will likely be because OnWillStart() returned
 474   // false somewhere in the chain of resource handlers.
 475   CallStartedCB(NULL, DOWNLOAD_INTERRUPT_REASON_NETWORK_FAILED);
 476
 477   // Remove output stream callback if a stream exists.
 478   if (stream_writer_)
 479     stream_writer_->RegisterCallback(base::Closure());
 480
 481   UMA_HISTOGRAM_TIMES("SB2.DownloadDuration",
 482                       base::TimeTicks::Now() - download_start_time_);
 483 }
 484
 485 }  // namespace content