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 DownloadResourceHandler::OnStartedCallback& started_cb,
  39     DownloadItem* item,
  40     net::Error error) {
  41   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  42
  43   if (started_cb.is_null())
  44     return;
  45   started_cb.Run(item, error);
  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 DownloadResourceHandler::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, net::ERR_ACCESS_DENIED);
  62     return;
  63   }
  64
  65   DownloadItem* item = download_manager->StartDownload(
  66       info.Pass(), stream.Pass());
  67
  68   // |item| can be NULL if the download has been removed.
  69   if (!started_cb.is_null())
  70     started_cb.Run(item, item ? net::OK : net::ERR_ABORTED);
  71 }
  72
  73 }  // namespace
  74
  75 const int DownloadResourceHandler::kDownloadByteStreamSize = 100 * 1024;
  76
  77 DownloadResourceHandler::DownloadResourceHandler(
  78     DownloadId id,
  79     net::URLRequest* request,
  80     const DownloadResourceHandler::OnStartedCallback& started_cb,
  81     scoped_ptr<DownloadSaveInfo> save_info)
  82     : download_id_(id),
  83       render_view_id_(0),               // Actually initialized below.
  84       content_length_(0),
  85       request_(request),
  86       started_cb_(started_cb),
  87       save_info_(save_info.Pass()),
  88       last_buffer_size_(0),
  89       bytes_read_(0),
  90       pause_count_(0),
  91       was_deferred_(false),
  92       on_response_started_called_(false) {
  93   ResourceRequestInfoImpl* info(ResourceRequestInfoImpl::ForRequest(request));
  94   global_id_ = info->GetGlobalRequestID();
  95   render_view_id_ = info->GetRouteID();
  96
  97   RecordDownloadCount(UNTHROTTLED_COUNT);
  98 }
  99
 100 bool DownloadResourceHandler::OnUploadProgress(int request_id,
 101                                                uint64 position,
 102                                                uint64 size) {
 103   return true;
 104 }
 105
 106 bool DownloadResourceHandler::OnRequestRedirected(
 107     int request_id,
 108     const GURL& url,
 109     ResourceResponse* response,
 110     bool* defer) {
 111   return true;
 112 }
 113
 114 // Send the download creation information to the download thread.
 115 bool DownloadResourceHandler::OnResponseStarted(
 116     int request_id,
 117     ResourceResponse* response,
 118     bool* defer) {
 119   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 120   // There can be only one (call)
 121   DCHECK(!on_response_started_called_);
 122   on_response_started_called_ = true;
 123
 124   VLOG(20) << __FUNCTION__ << "()" << DebugString()
 125            << " request_id = " << request_id;
 126   download_start_time_ = base::TimeTicks::Now();
 127
 128   // If it's a download, we don't want to poison the cache with it.
 129   request_->StopCaching();
 130
 131   // Lower priority as well, so downloads don't contend for resources
 132   // with main frames.
 133   request_->SetPriority(net::IDLE);
 134
 135   std::string content_disposition;
 136   request_->GetResponseHeaderByName("content-disposition",
 137                                     &content_disposition);
 138   SetContentDisposition(content_disposition);
 139   SetContentLength(response->head.content_length);
 140
 141   const ResourceRequestInfoImpl* request_info =
 142       ResourceRequestInfoImpl::ForRequest(request_);
 143
 144   // Deleted in DownloadManager.
 145   scoped_ptr<DownloadCreateInfo> info(new DownloadCreateInfo(
 146       base::Time::Now(), content_length_,
 147       request_->net_log(), request_info->HasUserGesture(),
 148       request_info->GetPageTransition()));
 149
 150   // Create the ByteStream for sending data to the download sink.
 151   scoped_ptr<ByteStreamReader> stream_reader;
 152   CreateByteStream(
 153       base::MessageLoopProxy::current(),
 154       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE),
 155       kDownloadByteStreamSize, &stream_writer_, &stream_reader);
 156   stream_writer_->RegisterCallback(
 157       base::Bind(&DownloadResourceHandler::ResumeRequest, AsWeakPtr()));
 158
 159   info->download_id = download_id_;
 160   info->url_chain = request_->url_chain();
 161   info->referrer_url = GURL(request_->referrer());
 162   info->start_time = base::Time::Now();
 163   info->total_bytes = content_length_;
 164   info->has_user_gesture = request_info->HasUserGesture();
 165   info->content_disposition = content_disposition_;
 166   info->mime_type = response->head.mime_type;
 167   info->remote_address = request_->GetSocketAddress().host();
 168   RecordDownloadMimeType(info->mime_type);
 169   RecordDownloadContentDisposition(info->content_disposition);
 170
 171   info->request_handle =
 172       DownloadRequestHandle(AsWeakPtr(), global_id_.child_id,
 173                             render_view_id_, global_id_.request_id);
 174
 175   // Get the last modified time and etag.
 176   const net::HttpResponseHeaders* headers = request_->response_headers();
 177   if (headers) {
 178     std::string last_modified_hdr;
 179     std::string etag;
 180     if (headers->EnumerateHeader(NULL, "Last-Modified", &last_modified_hdr))
 181       info->last_modified = last_modified_hdr;
 182     if (headers->EnumerateHeader(NULL, "ETag", &etag))
 183       info->etag = etag;
 184
 185     int status = headers->response_code();
 186     if (2 == status / 100  && status != net::HTTP_PARTIAL_CONTENT) {
 187       // Success & not range response; if we asked for a range, we didn't
 188       // get it--reset the file pointers to reflect that.
 189       save_info_->offset = 0;
 190       save_info_->hash_state = "";
 191     }
 192   }
 193
 194   std::string content_type_header;
 195   if (!response->head.headers.get() ||
 196       !response->head.headers->GetMimeType(&content_type_header))
 197     content_type_header = "";
 198   info->original_mime_type = content_type_header;
 199
 200   if (!response->head.headers.get() ||
 201       !response->head.headers->EnumerateHeader(
 202           NULL, "Accept-Ranges", &accept_ranges_)) {
 203     accept_ranges_ = "";
 204   }
 205
 206   info->save_info = save_info_.Pass();
 207
 208   BrowserThread::PostTask(
 209       BrowserThread::UI, FROM_HERE,
 210       base::Bind(&StartOnUIThread,
 211                  base::Passed(&info),
 212                  base::Passed(&stream_reader),
 213                  // Pass to StartOnUIThread so that variable
 214                  // access is always on IO thread but function
 215                  // is called on UI thread.
 216                  started_cb_));
 217   // Guaranteed to be called in StartOnUIThread
 218   started_cb_.Reset();
 219
 220   return true;
 221 }
 222
 223 void DownloadResourceHandler::CallStartedCB(
 224     DownloadItem* item, net::Error error) {
 225   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 226   if (started_cb_.is_null())
 227     return;
 228   BrowserThread::PostTask(
 229       BrowserThread::UI, FROM_HERE,
 230       base::Bind(&CallStartedCBOnUIThread, started_cb_, item, error));
 231   started_cb_.Reset();
 232 }
 233
 234 bool DownloadResourceHandler::OnWillStart(int request_id,
 235                                           const GURL& url,
 236                                           bool* defer) {
 237   return true;
 238 }
 239
 240 // Create a new buffer, which will be handed to the download thread for file
 241 // writing and deletion.
 242 bool DownloadResourceHandler::OnWillRead(int request_id, net::IOBuffer** buf,
 243                                          int* buf_size, int min_size) {
 244   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 245   DCHECK(buf && buf_size);
 246   DCHECK(!read_buffer_.get());
 247
 248   *buf_size = min_size < 0 ? kReadBufSize : min_size;
 249   last_buffer_size_ = *buf_size;
 250   read_buffer_ = new net::IOBuffer(*buf_size);
 251   *buf = read_buffer_.get();
 252   return true;
 253 }
 254
 255 // Pass the buffer to the download file writer.
 256 bool DownloadResourceHandler::OnReadCompleted(int request_id, int bytes_read,
 257                                               bool* defer) {
 258   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 259   DCHECK(read_buffer_.get());
 260
 261   base::TimeTicks now(base::TimeTicks::Now());
 262   if (!last_read_time_.is_null()) {
 263     double seconds_since_last_read = (now - last_read_time_).InSecondsF();
 264     if (now == last_read_time_)
 265       // Use 1/10 ms as a "very small number" so that we avoid
 266       // divide-by-zero error and still record a very high potential bandwidth.
 267       seconds_since_last_read = 0.00001;
 268
 269     double actual_bandwidth = (bytes_read)/seconds_since_last_read;
 270     double potential_bandwidth = last_buffer_size_/seconds_since_last_read;
 271     RecordBandwidth(actual_bandwidth, potential_bandwidth);
 272   }
 273   last_read_time_ = now;
 274
 275   if (!bytes_read)
 276     return true;
 277   bytes_read_ += bytes_read;
 278   DCHECK(read_buffer_.get());
 279
 280   // Take the data ship it down the stream.  If the stream is full, pause the
 281   // request; the stream callback will resume it.
 282   if (!stream_writer_->Write(read_buffer_, bytes_read)) {
 283     PauseRequest();
 284     *defer = was_deferred_ = true;
 285     last_stream_pause_time_ = now;
 286   }
 287
 288   read_buffer_ = NULL;  // Drop our reference.
 289
 290   if (pause_count_ > 0)
 291     *defer = was_deferred_ = true;
 292
 293   return true;
 294 }
 295
 296 bool DownloadResourceHandler::OnResponseCompleted(
 297     int request_id,
 298     const net::URLRequestStatus& status,
 299     const std::string& security_info) {
 300   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 301   int response_code = status.is_success() ? request_->GetResponseCode() : 0;
 302   VLOG(20) << __FUNCTION__ << "()" << DebugString()
 303            << " request_id = " << request_id
 304            << " status.status() = " << status.status()
 305            << " status.error() = " << status.error()
 306            << " response_code = " << response_code;
 307
 308   net::Error error_code = net::OK;
 309   if (status.status() == net::URLRequestStatus::FAILED ||
 310       // Note cancels as failures too.
 311       status.status() == net::URLRequestStatus::CANCELED) {
 312     error_code = static_cast<net::Error>(status.error());  // Normal case.
 313     // Make sure that at least the fact of failure comes through.
 314     if (error_code == net::OK)
 315       error_code = net::ERR_FAILED;
 316   }
 317
 318   // ERR_CONTENT_LENGTH_MISMATCH and ERR_INCOMPLETE_CHUNKED_ENCODING are
 319   // allowed since a number of servers in the wild close the connection too
 320   // early by mistake. Other browsers - IE9, Firefox 11.0, and Safari 5.1.4 -
 321   // treat downloads as complete in both cases, so we follow their lead.
 322   if (error_code == net::ERR_CONTENT_LENGTH_MISMATCH ||
 323       error_code == net::ERR_INCOMPLETE_CHUNKED_ENCODING) {
 324     error_code = net::OK;
 325   }
 326   DownloadInterruptReason reason =
 327       ConvertNetErrorToInterruptReason(
 328         error_code, DOWNLOAD_INTERRUPT_FROM_NETWORK);
 329
 330   if (status.status() == net::URLRequestStatus::CANCELED &&
 331       status.error() == net::ERR_ABORTED) {
 332     // CANCELED + ERR_ABORTED == something outside of the network
 333     // stack cancelled the request.  There aren't that many things that
 334     // could do this to a download request (whose lifetime is separated from
 335     // the tab from which it came).  We map this to USER_CANCELLED as the
 336     // case we know about (system suspend because of laptop close) corresponds
 337     // to a user action.
 338     // TODO(ahendrickson) -- Find a better set of codes to use here, as
 339     // CANCELED/ERR_ABORTED can occur for reasons other than user cancel.
 340     reason = DOWNLOAD_INTERRUPT_REASON_USER_CANCELED;
 341   }
 342
 343   if (status.is_success() &&
 344       reason == DOWNLOAD_INTERRUPT_REASON_NONE &&
 345       request_->response_headers()) {
 346     // Handle server's response codes.
 347     switch(response_code) {
 348       case -1:                          // Non-HTTP request.
 349       case net::HTTP_OK:
 350       case net::HTTP_CREATED:
 351       case net::HTTP_ACCEPTED:
 352       case net::HTTP_NON_AUTHORITATIVE_INFORMATION:
 353       case net::HTTP_RESET_CONTENT:
 354       case net::HTTP_PARTIAL_CONTENT:
 355         // Expected successful codes.
 356         break;
 357       case net::HTTP_NO_CONTENT:
 358       case net::HTTP_NOT_FOUND:
 359         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_BAD_CONTENT;
 360         break;
 361       case net::HTTP_PRECONDITION_FAILED:
 362         // Failed our 'If-Unmodified-Since' or 'If-Match'; see
 363         // download_manager_impl.cc BeginDownload()
 364         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_PRECONDITION;
 365         break;
 366       case net::HTTP_REQUESTED_RANGE_NOT_SATISFIABLE:
 367         // Retry by downloading from the start automatically:
 368         // If we haven't received data when we get this error, we won't.
 369         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_NO_RANGE;
 370         break;
 371       default:    // All other errors.
 372         // Redirection and informational codes should have been handled earlier
 373         // in the stack.
 374         DCHECK_NE(3, response_code / 100);
 375         DCHECK_NE(1, response_code / 100);
 376         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_FAILED;
 377         break;
 378     }
 379   }
 380
 381   RecordAcceptsRanges(accept_ranges_, bytes_read_);
 382   RecordNetworkBlockage(
 383       base::TimeTicks::Now() - download_start_time_, total_pause_time_);
 384
 385   CallStartedCB(NULL, error_code);
 386
 387   // Send the info down the stream.  Conditional is in case we get
 388   // OnResponseCompleted without OnResponseStarted.
 389   if (stream_writer_)
 390     stream_writer_->Close(reason);
 391
 392   // If the error mapped to something unknown, record it so that
 393   // we can drill down.
 394   if (reason == DOWNLOAD_INTERRUPT_REASON_NETWORK_FAILED) {
 395     UMA_HISTOGRAM_CUSTOM_ENUMERATION("Download.MapErrorNetworkFailed",
 396                                      std::abs(status.error()),
 397                                      net::GetAllErrorCodesForUma());
 398   }
 399
 400   stream_writer_.reset();  // We no longer need the stream.
 401   read_buffer_ = NULL;
 402
 403   return true;
 404 }
 405
 406 void DownloadResourceHandler::OnDataDownloaded(
 407     int request_id,
 408     int bytes_downloaded) {
 409   NOTREACHED();
 410 }
 411
 412 // If the content-length header is not present (or contains something other
 413 // than numbers), the incoming content_length is -1 (unknown size).
 414 // Set the content length to 0 to indicate unknown size to DownloadManager.
 415 void DownloadResourceHandler::SetContentLength(const int64& content_length) {
 416   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 417   content_length_ = 0;
 418   if (content_length > 0)
 419     content_length_ = content_length;
 420 }
 421
 422 void DownloadResourceHandler::SetContentDisposition(
 423     const std::string& content_disposition) {
 424   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 425   content_disposition_ = content_disposition;
 426 }
 427
 428 void DownloadResourceHandler::PauseRequest() {
 429   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 430
 431   ++pause_count_;
 432 }
 433
 434 void DownloadResourceHandler::ResumeRequest() {
 435   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 436   DCHECK_LT(0, pause_count_);
 437
 438   --pause_count_;
 439
 440   if (!was_deferred_)
 441     return;
 442   if (pause_count_ > 0)
 443     return;
 444
 445   was_deferred_ = false;
 446   if (!last_stream_pause_time_.is_null()) {
 447     total_pause_time_ += (base::TimeTicks::Now() - last_stream_pause_time_);
 448     last_stream_pause_time_ = base::TimeTicks();
 449   }
 450
 451   controller()->Resume();
 452 }
 453
 454 void DownloadResourceHandler::CancelRequest() {
 455   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 456
 457   ResourceDispatcherHostImpl::Get()->CancelRequest(
 458       global_id_.child_id,
 459       global_id_.request_id,
 460       false);
 461 }
 462
 463 std::string DownloadResourceHandler::DebugString() const {
 464   return base::StringPrintf("{"
 465                             " url_ = " "\"%s\""
 466                             " global_id_ = {"
 467                             " child_id = " "%d"
 468                             " request_id = " "%d"
 469                             " }"
 470                             " render_view_id_ = " "%d"
 471                             " }",
 472                             request_ ?
 473                                 request_->url().spec().c_str() :
 474                                 "<NULL request>",
 475                             global_id_.child_id,
 476                             global_id_.request_id,
 477                             render_view_id_);
 478 }
 479
 480 DownloadResourceHandler::~DownloadResourceHandler() {
 481   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 482
 483   // This won't do anything if the callback was called before.
 484   // If it goes through, it will likely be because OnWillStart() returned
 485   // false somewhere in the chain of resource handlers.
 486   CallStartedCB(NULL, net::ERR_ACCESS_DENIED);
 487
 488   // Remove output stream callback if a stream exists.
 489   if (stream_writer_)
 490     stream_writer_->RegisterCallback(base::Closure());
 491
 492   UMA_HISTOGRAM_TIMES("SB2.DownloadDuration",
 493                       base::TimeTicks::Now() - download_start_time_);
 494 }
 495
 496 }  // namespace content