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     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 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, net::ERR_ACCESS_DENIED);
  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, net::Error error) {
 210   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 211   if (started_cb_.is_null())
 212     return;
 213   BrowserThread::PostTask(
 214       BrowserThread::UI, FROM_HERE,
 215       base::Bind(&CallStartedCBOnUIThread, started_cb_, item, error));
 216   started_cb_.Reset();
 217 }
 218
 219 bool DownloadResourceHandler::OnWillStart(int request_id,
 220                                           const GURL& url,
 221                                           bool* defer) {
 222   return true;
 223 }
 224
 225 bool DownloadResourceHandler::OnBeforeNetworkStart(int request_id,
 226                                                    const GURL& url,
 227                                                    bool* defer) {
 228   return true;
 229 }
 230
 231 // Create a new buffer, which will be handed to the download thread for file
 232 // writing and deletion.
 233 bool DownloadResourceHandler::OnWillRead(int request_id,
 234                                          scoped_refptr<net::IOBuffer>* buf,
 235                                          int* buf_size,
 236                                          int min_size) {
 237   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 238   DCHECK(buf && buf_size);
 239   DCHECK(!read_buffer_.get());
 240
 241   *buf_size = min_size < 0 ? kReadBufSize : min_size;
 242   last_buffer_size_ = *buf_size;
 243   read_buffer_ = new net::IOBuffer(*buf_size);
 244   *buf = read_buffer_.get();
 245   return true;
 246 }
 247
 248 // Pass the buffer to the download file writer.
 249 bool DownloadResourceHandler::OnReadCompleted(int request_id, int bytes_read,
 250                                               bool* defer) {
 251   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 252   DCHECK(read_buffer_.get());
 253
 254   base::TimeTicks now(base::TimeTicks::Now());
 255   if (!last_read_time_.is_null()) {
 256     double seconds_since_last_read = (now - last_read_time_).InSecondsF();
 257     if (now == last_read_time_)
 258       // Use 1/10 ms as a "very small number" so that we avoid
 259       // divide-by-zero error and still record a very high potential bandwidth.
 260       seconds_since_last_read = 0.00001;
 261
 262     double actual_bandwidth = (bytes_read)/seconds_since_last_read;
 263     double potential_bandwidth = last_buffer_size_/seconds_since_last_read;
 264     RecordBandwidth(actual_bandwidth, potential_bandwidth);
 265   }
 266   last_read_time_ = now;
 267
 268   if (!bytes_read)
 269     return true;
 270   bytes_read_ += bytes_read;
 271   DCHECK(read_buffer_.get());
 272
 273   // Take the data ship it down the stream.  If the stream is full, pause the
 274   // request; the stream callback will resume it.
 275   if (!stream_writer_->Write(read_buffer_, bytes_read)) {
 276     PauseRequest();
 277     *defer = was_deferred_ = true;
 278     last_stream_pause_time_ = now;
 279   }
 280
 281   read_buffer_ = NULL;  // Drop our reference.
 282
 283   if (pause_count_ > 0)
 284     *defer = was_deferred_ = true;
 285
 286   return true;
 287 }
 288
 289 void DownloadResourceHandler::OnResponseCompleted(
 290     int request_id,
 291     const net::URLRequestStatus& status,
 292     const std::string& security_info,
 293     bool* defer) {
 294   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 295   int response_code = status.is_success() ? request()->GetResponseCode() : 0;
 296   VLOG(20) << __FUNCTION__ << "()" << DebugString()
 297            << " request_id = " << request_id
 298            << " status.status() = " << status.status()
 299            << " status.error() = " << status.error()
 300            << " response_code = " << response_code;
 301
 302   net::Error error_code = net::OK;
 303   if (status.status() == net::URLRequestStatus::FAILED ||
 304       // Note cancels as failures too.
 305       status.status() == net::URLRequestStatus::CANCELED) {
 306     error_code = static_cast<net::Error>(status.error());  // Normal case.
 307     // Make sure that at least the fact of failure comes through.
 308     if (error_code == net::OK)
 309       error_code = net::ERR_FAILED;
 310   }
 311
 312   // ERR_CONTENT_LENGTH_MISMATCH and ERR_INCOMPLETE_CHUNKED_ENCODING are
 313   // allowed since a number of servers in the wild close the connection too
 314   // early by mistake. Other browsers - IE9, Firefox 11.0, and Safari 5.1.4 -
 315   // treat downloads as complete in both cases, so we follow their lead.
 316   if (error_code == net::ERR_CONTENT_LENGTH_MISMATCH ||
 317       error_code == net::ERR_INCOMPLETE_CHUNKED_ENCODING) {
 318     error_code = net::OK;
 319   }
 320   DownloadInterruptReason reason =
 321       ConvertNetErrorToInterruptReason(
 322         error_code, DOWNLOAD_INTERRUPT_FROM_NETWORK);
 323
 324   if (status.status() == net::URLRequestStatus::CANCELED &&
 325       status.error() == net::ERR_ABORTED) {
 326     // CANCELED + ERR_ABORTED == something outside of the network
 327     // stack cancelled the request.  There aren't that many things that
 328     // could do this to a download request (whose lifetime is separated from
 329     // the tab from which it came).  We map this to USER_CANCELLED as the
 330     // case we know about (system suspend because of laptop close) corresponds
 331     // to a user action.
 332     // TODO(ahendrickson) -- Find a better set of codes to use here, as
 333     // CANCELED/ERR_ABORTED can occur for reasons other than user cancel.
 334     reason = DOWNLOAD_INTERRUPT_REASON_USER_CANCELED;
 335   }
 336
 337   if (status.is_success() &&
 338       reason == DOWNLOAD_INTERRUPT_REASON_NONE &&
 339       request()->response_headers()) {
 340     // Handle server's response codes.
 341     switch(response_code) {
 342       case -1:                          // Non-HTTP request.
 343       case net::HTTP_OK:
 344       case net::HTTP_CREATED:
 345       case net::HTTP_ACCEPTED:
 346       case net::HTTP_NON_AUTHORITATIVE_INFORMATION:
 347       case net::HTTP_RESET_CONTENT:
 348       case net::HTTP_PARTIAL_CONTENT:
 349         // Expected successful codes.
 350         break;
 351       case net::HTTP_NO_CONTENT:
 352       case net::HTTP_NOT_FOUND:
 353         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_BAD_CONTENT;
 354         break;
 355       case net::HTTP_PRECONDITION_FAILED:
 356         // Failed our 'If-Unmodified-Since' or 'If-Match'; see
 357         // download_manager_impl.cc BeginDownload()
 358         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_PRECONDITION;
 359         break;
 360       case net::HTTP_REQUESTED_RANGE_NOT_SATISFIABLE:
 361         // Retry by downloading from the start automatically:
 362         // If we haven't received data when we get this error, we won't.
 363         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_NO_RANGE;
 364         break;
 365       default:    // All other errors.
 366         // Redirection and informational codes should have been handled earlier
 367         // in the stack.
 368         DCHECK_NE(3, response_code / 100);
 369         DCHECK_NE(1, response_code / 100);
 370         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_FAILED;
 371         break;
 372     }
 373   }
 374
 375   std::string accept_ranges;
 376   bool has_strong_validators = false;
 377   if (request()->response_headers()) {
 378     request()->response_headers()->EnumerateHeader(
 379         NULL, "Accept-Ranges", &accept_ranges);
 380     has_strong_validators =
 381         request()->response_headers()->HasStrongValidators();
 382   }
 383   RecordAcceptsRanges(accept_ranges, bytes_read_, has_strong_validators);
 384   RecordNetworkBlockage(base::TimeTicks::Now() - download_start_time_,
 385                         total_pause_time_);
 386
 387   CallStartedCB(NULL, error_code);
 388
 389   // Send the info down the stream.  Conditional is in case we get
 390   // OnResponseCompleted without OnResponseStarted.
 391   if (stream_writer_)
 392     stream_writer_->Close(reason);
 393
 394   // If the error mapped to something unknown, record it so that
 395   // we can drill down.
 396   if (reason == DOWNLOAD_INTERRUPT_REASON_NETWORK_FAILED) {
 397     UMA_HISTOGRAM_CUSTOM_ENUMERATION("Download.MapErrorNetworkFailed",
 398                                      std::abs(status.error()),
 399                                      net::GetAllErrorCodesForUma());
 400   }
 401
 402   stream_writer_.reset();  // We no longer need the stream.
 403   read_buffer_ = NULL;
 404 }
 405
 406 void DownloadResourceHandler::OnDataDownloaded(
 407     int request_id,
 408     int bytes_downloaded) {
 409   NOTREACHED();
 410 }
 411
 412 void DownloadResourceHandler::PauseRequest() {
 413   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 414
 415   ++pause_count_;
 416 }
 417
 418 void DownloadResourceHandler::ResumeRequest() {
 419   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 420   DCHECK_LT(0, pause_count_);
 421
 422   --pause_count_;
 423
 424   if (!was_deferred_)
 425     return;
 426   if (pause_count_ > 0)
 427     return;
 428
 429   was_deferred_ = false;
 430   if (!last_stream_pause_time_.is_null()) {
 431     total_pause_time_ += (base::TimeTicks::Now() - last_stream_pause_time_);
 432     last_stream_pause_time_ = base::TimeTicks();
 433   }
 434
 435   controller()->Resume();
 436 }
 437
 438 void DownloadResourceHandler::CancelRequest() {
 439   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 440
 441   const ResourceRequestInfo* info = GetRequestInfo();
 442   ResourceDispatcherHostImpl::Get()->CancelRequest(
 443       info->GetChildID(),
 444       info->GetRequestID(),
 445       false);
 446 }
 447
 448 std::string DownloadResourceHandler::DebugString() const {
 449   const ResourceRequestInfo* info = GetRequestInfo();
 450   return base::StringPrintf("{"
 451                             " url_ = " "\"%s\""
 452                             " info = {"
 453                             " child_id = " "%d"
 454                             " request_id = " "%d"
 455                             " route_id = " "%d"
 456                             " }"
 457                             " }",
 458                             request() ?
 459                                 request()->url().spec().c_str() :
 460                                 "<NULL request>",
 461                             info->GetChildID(),
 462                             info->GetRequestID(),
 463                             info->GetRouteID());
 464 }
 465
 466 DownloadResourceHandler::~DownloadResourceHandler() {
 467   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 468
 469   // This won't do anything if the callback was called before.
 470   // If it goes through, it will likely be because OnWillStart() returned
 471   // false somewhere in the chain of resource handlers.
 472   CallStartedCB(NULL, net::ERR_ACCESS_DENIED);
 473
 474   // Remove output stream callback if a stream exists.
 475   if (stream_writer_)
 476     stream_writer_->RegisterCallback(base::Closure());
 477
 478   UMA_HISTOGRAM_TIMES("SB2.DownloadDuration",
 479                       base::TimeTicks::Now() - download_start_time_);
 480 }
 481
 482 }  // namespace content