src/chrome/renderer/net/net_error_helper_core.cc

   1 // Copyright 2013 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 "chrome/renderer/net/net_error_helper_core.h"
   6
   7 #include <string>
   8
   9 #include "base/bind.h"
  10 #include "base/callback.h"
  11 #include "base/i18n/rtl.h"
  12 #include "base/json/json_reader.h"
  13 #include "base/json/json_writer.h"
  14 #include "base/location.h"
  15 #include "base/metrics/histogram.h"
  16 #include "base/strings/string16.h"
  17 #include "base/values.h"
  18 #include "chrome/common/localized_error.h"
  19 #include "grit/generated_resources.h"
  20 #include "net/base/escape.h"
  21 #include "net/base/net_errors.h"
  22 #include "net/base/net_util.h"
  23 #include "third_party/WebKit/public/platform/WebString.h"
  24 #include "third_party/WebKit/public/platform/WebURLError.h"
  25 #include "ui/base/l10n/l10n_util.h"
  26 #include "url/gurl.h"
  27
  28 namespace {
  29
  30 struct CorrectionTypeToResourceTable {
  31   int resource_id;
  32   const char* correction_type;
  33 };
  34
  35 const CorrectionTypeToResourceTable kCorrectionResourceTable[] = {
  36   {IDS_ERRORPAGES_SUGGESTION_VISIT_GOOGLE_CACHE, "cachedPage"},
  37   // "reloadPage" is has special handling.
  38   {IDS_ERRORPAGES_SUGGESTION_CORRECTED_URL, "urlCorrection"},
  39   {IDS_ERRORPAGES_SUGGESTION_ALTERNATE_URL, "siteDomain"},
  40   {IDS_ERRORPAGES_SUGGESTION_ALTERNATE_URL, "host"},
  41   {IDS_ERRORPAGES_SUGGESTION_ALTERNATE_URL, "sitemap"},
  42   {IDS_ERRORPAGES_SUGGESTION_ALTERNATE_URL, "pathParentFolder"},
  43   // "siteSearchQuery" is not yet supported.
  44   // TODO(mmenke):  Figure out what format "siteSearchQuery" uses for its
  45   // suggestions.
  46   // "webSearchQuery" has special handling.
  47   {IDS_ERRORPAGES_SUGGESTION_ALTERNATE_URL, "contentOverlap"},
  48   {IDS_ERRORPAGES_SUGGESTION_CORRECTED_URL, "emphasizedUrlCorrection"},
  49 };
  50
  51 base::TimeDelta GetAutoReloadTime(size_t reload_count) {
  52   static const int kDelaysMs[] = {
  53     0, 5000, 30000, 60000, 300000, 600000, 1800000
  54   };
  55   if (reload_count >= arraysize(kDelaysMs))
  56     reload_count = arraysize(kDelaysMs) - 1;
  57   return base::TimeDelta::FromMilliseconds(kDelaysMs[reload_count]);
  58 }
  59
  60 // Returns whether |net_error| is a DNS-related error (and therefore whether
  61 // the tab helper should start a DNS probe after receiving it.)
  62 bool IsDnsError(const blink::WebURLError& error) {
  63   return error.domain.utf8() == net::kErrorDomain &&
  64          (error.reason == net::ERR_NAME_NOT_RESOLVED ||
  65           error.reason == net::ERR_NAME_RESOLUTION_FAILED);
  66 }
  67
  68 GURL SanitizeURL(const GURL& url) {
  69   GURL::Replacements remove_params;
  70   remove_params.ClearUsername();
  71   remove_params.ClearPassword();
  72   remove_params.ClearQuery();
  73   remove_params.ClearRef();
  74   return url.ReplaceComponents(remove_params);
  75 }
  76
  77 // If URL correction information should be retrieved remotely for a main frame
  78 // load that failed with |error|, returns true and sets
  79 // |correction_request_body| to be the body for the correction request.
  80 bool GetFixUrlRequestBody(const blink::WebURLError& error,
  81                           const std::string& language,
  82                           const std::string& country_code,
  83                           const std::string& api_key,
  84                           std::string* correction_request_body) {
  85   // Parameter to send to the correction service indicating the error type.
  86   std::string error_param;
  87
  88   std::string domain = error.domain.utf8();
  89   if (domain == "http" && error.reason == 404) {
  90     error_param = "http404";
  91   } else if (IsDnsError(error)) {
  92     error_param = "dnserror";
  93   } else if (domain == net::kErrorDomain &&
  94              (error.reason == net::ERR_CONNECTION_FAILED ||
  95               error.reason == net::ERR_CONNECTION_REFUSED ||
  96               error.reason == net::ERR_ADDRESS_UNREACHABLE ||
  97               error.reason == net::ERR_CONNECTION_TIMED_OUT)) {
  98     error_param = "connectionFailure";
  99   } else {
 100     return false;
 101   }
 102
 103   // Don't use the correction service for HTTPS (for privacy reasons).
 104   GURL unreachable_url(error.unreachableURL);
 105   if (unreachable_url.SchemeIsSecure())
 106     return false;
 107
 108   // TODO(yuusuke): Change to net::FormatUrl when Link Doctor becomes
 109   // unicode-capable.
 110   std::string spec_to_send = SanitizeURL(unreachable_url).spec();
 111
 112   // Notify navigation correction service of the url truncation by sending of
 113   // "?" at the end.
 114   if (unreachable_url.has_query())
 115     spec_to_send.append("?");
 116
 117   // Assemble request body, which is a JSON string.
 118   // TODO(mmenke):  Investigate open sourcing the relevant protocol buffers and
 119   //                using those directly instead.
 120
 121   base::DictionaryValue request_dict;
 122   request_dict.SetString("method", "linkdoctor.fixurl.fixurl");
 123   request_dict.SetString("apiVersion", "v1");
 124
 125   base::DictionaryValue* params_dict = new base::DictionaryValue();
 126   request_dict.Set("params", params_dict);
 127
 128   params_dict->SetString("key", api_key);
 129   params_dict->SetString("urlQuery", spec_to_send);
 130   params_dict->SetString("clientName", "chrome");
 131   params_dict->SetString("error", error_param);
 132
 133   if (!language.empty())
 134     params_dict->SetString("language", language);
 135
 136   if (!country_code.empty())
 137     params_dict->SetString("originCountry", country_code);
 138
 139   base::JSONWriter::Write(&request_dict, correction_request_body);
 140   return true;
 141 }
 142
 143 base::string16 FormatURLForDisplay(const GURL& url, bool is_rtl,
 144                                    const std::string accept_languages) {
 145   // Translate punycode into UTF8, unescape UTF8 URLs.
 146   base::string16 url_for_display(net::FormatUrl(
 147       url, accept_languages, net::kFormatUrlOmitNothing,
 148       net::UnescapeRule::NORMAL, NULL, NULL, NULL));
 149   // URLs are always LTR.
 150   if (is_rtl)
 151     base::i18n::WrapStringWithLTRFormatting(&url_for_display);
 152   return url_for_display;
 153 }
 154
 155 LocalizedError::ErrorPageParams* ParseAdditionalSuggestions(
 156     const std::string& data,
 157     const GURL& original_url,
 158     const GURL& search_url,
 159     const std::string& accept_languages,
 160     bool is_rtl) {
 161   scoped_ptr<base::Value> parsed(base::JSONReader::Read(data));
 162   if (!parsed)
 163     return NULL;
 164   // TODO(mmenke):  Open source related protocol buffers and use them directly.
 165   base::DictionaryValue* parsed_dict;
 166   base::ListValue* corrections;
 167   if (!parsed->GetAsDictionary(&parsed_dict))
 168     return NULL;
 169   if (!parsed_dict->GetList("result.UrlCorrections", &corrections))
 170     return NULL;
 171
 172   // Version of URL for display in suggestions.  It has to be sanitized first
 173   // because any received suggestions will be relative to the sanitized URL.
 174   base::string16 original_url_for_display =
 175       FormatURLForDisplay(SanitizeURL(original_url), is_rtl, accept_languages);
 176
 177   scoped_ptr<LocalizedError::ErrorPageParams> params(
 178       new LocalizedError::ErrorPageParams());
 179   params->override_suggestions.reset(new base::ListValue());
 180   scoped_ptr<base::ListValue> parsed_corrections(new base::ListValue());
 181   for (base::ListValue::iterator it = corrections->begin();
 182        it != corrections->end(); ++it) {
 183     base::DictionaryValue* correction;
 184     if (!(*it)->GetAsDictionary(&correction))
 185       continue;
 186
 187     // Doesn't seem like a good idea to show these.
 188     bool is_porn;
 189     if (correction->GetBoolean("isPorn", &is_porn) && is_porn)
 190       continue;
 191     if (correction->GetBoolean("isSoftPorn", &is_porn) && is_porn)
 192       continue;
 193
 194     std::string correction_type;
 195     std::string url_correction;
 196     if (!correction->GetString("correctionType", &correction_type) ||
 197         !correction->GetString("urlCorrection", &url_correction)) {
 198       continue;
 199     }
 200
 201     std::string click_tracking_url;
 202     correction->GetString("clickTrackingUrl", &click_tracking_url);
 203
 204     if (correction_type == "reloadPage") {
 205       params->suggest_reload = true;
 206       continue;
 207     }
 208
 209     if (correction_type == "webSearchQuery") {
 210       // If there are mutliple searches suggested, use the first suggestion.
 211       if (params->search_terms.empty()) {
 212         params->search_url = search_url;
 213         params->search_terms = url_correction;
 214       }
 215       continue;
 216     }
 217
 218     size_t correction_index;
 219     for (correction_index = 0;
 220          correction_index < arraysize(kCorrectionResourceTable);
 221          ++correction_index) {
 222       if (correction_type !=
 223               kCorrectionResourceTable[correction_index].correction_type) {
 224         continue;
 225       }
 226       base::DictionaryValue* suggest = new base::DictionaryValue();
 227       suggest->SetString("header",
 228           l10n_util::GetStringUTF16(
 229               kCorrectionResourceTable[correction_index].resource_id));
 230       suggest->SetString("urlCorrection",
 231           !click_tracking_url.empty() ? click_tracking_url :
 232                                         url_correction);
 233       suggest->SetString(
 234           "urlCorrectionForDisplay",
 235           FormatURLForDisplay(GURL(url_correction), is_rtl, accept_languages));
 236       suggest->SetString("originalUrlForDisplay", original_url_for_display);
 237       params->override_suggestions->Append(suggest);
 238       break;
 239     }
 240   }
 241
 242   if (params->override_suggestions->empty() &&
 243       !params->search_url.is_valid()) {
 244     return NULL;
 245   }
 246   return params.release();
 247 }
 248
 249 }  // namespace
 250
 251 struct NetErrorHelperCore::ErrorPageInfo {
 252   ErrorPageInfo(blink::WebURLError error, bool was_failed_post)
 253       : error(error),
 254         was_failed_post(was_failed_post),
 255         needs_dns_updates(false),
 256         is_finished_loading(false) {
 257   }
 258
 259   // Information about the failed page load.
 260   blink::WebURLError error;
 261   bool was_failed_post;
 262
 263   // Information about the status of the error page.
 264
 265   // True if a page is a DNS error page and has not yet received a final DNS
 266   // probe status.
 267   bool needs_dns_updates;
 268
 269   // Navigation correction service url, which will be used in response to
 270   // certain types of network errors.  This is also stored by the
 271   // NetErrorHelperCore itself, but it stored here as well in case its modified
 272   // in the middle of an error page load.  Empty when no error page should be
 273   // fetched, or if there's already a fetch in progress.
 274   GURL navigation_correction_url;
 275
 276   // Request body to use when requesting corrections from a web service.
 277   // TODO(mmenke):  Investigate loading the error page at the same time as
 278   //                the blank page is loading, to get rid of these.
 279   std::string navigation_correction_request_body;
 280
 281   // True if a page has completed loading, at which point it can receive
 282   // updates.
 283   bool is_finished_loading;
 284 };
 285
 286 bool NetErrorHelperCore::IsReloadableError(
 287     const NetErrorHelperCore::ErrorPageInfo& info) {
 288   return info.error.domain.utf8() == net::kErrorDomain &&
 289          info.error.reason != net::ERR_ABORTED &&
 290          !info.was_failed_post;
 291 }
 292
 293 NetErrorHelperCore::NetErrorHelperCore(Delegate* delegate)
 294     : delegate_(delegate),
 295       last_probe_status_(chrome_common_net::DNS_PROBE_POSSIBLE),
 296       auto_reload_enabled_(false),
 297       auto_reload_timer_(new base::Timer(false, false)),
 298       // TODO(ellyjones): Make online_ accurate at object creation.
 299       online_(true),
 300       auto_reload_count_(0),
 301       can_auto_reload_page_(false) {
 302 }
 303
 304 NetErrorHelperCore::~NetErrorHelperCore() {
 305   if (committed_error_page_info_ && can_auto_reload_page_) {
 306     UMA_HISTOGRAM_CUSTOM_ENUMERATION("Net.AutoReload.ErrorAtStop",
 307                                      -committed_error_page_info_->error.reason,
 308                                      net::GetAllErrorCodesForUma());
 309     UMA_HISTOGRAM_COUNTS("Net.AutoReload.CountAtStop", auto_reload_count_);
 310   }
 311 }
 312
 313 void NetErrorHelperCore::CancelPendingFetches() {
 314   // Cancel loading the alternate error page, and prevent any pending error page
 315   // load from starting a new error page load.  Swapping in the error page when
 316   // it's finished loading could abort the navigation, otherwise.
 317   if (committed_error_page_info_ && can_auto_reload_page_) {
 318     UMA_HISTOGRAM_CUSTOM_ENUMERATION("Net.AutoReload.ErrorAtStop",
 319                                      -committed_error_page_info_->error.reason,
 320                                      net::GetAllErrorCodesForUma());
 321     UMA_HISTOGRAM_COUNTS("Net.AutoReload.CountAtStop", auto_reload_count_);
 322   }
 323   if (committed_error_page_info_) {
 324     committed_error_page_info_->navigation_correction_url = GURL();
 325     committed_error_page_info_->navigation_correction_request_body.clear();
 326   }
 327   if (pending_error_page_info_) {
 328     pending_error_page_info_->navigation_correction_url = GURL();
 329     pending_error_page_info_->navigation_correction_request_body.clear();
 330   }
 331   delegate_->CancelFetchNavigationCorrections();
 332   auto_reload_timer_->Stop();
 333   can_auto_reload_page_ = false;
 334 }
 335
 336 void NetErrorHelperCore::OnStop() {
 337   CancelPendingFetches();
 338   auto_reload_count_ = 0;
 339 }
 340
 341 void NetErrorHelperCore::OnStartLoad(FrameType frame_type, PageType page_type) {
 342   if (frame_type != MAIN_FRAME)
 343     return;
 344
 345   // If there's no pending error page information associated with the page load,
 346   // or the new page is not an error page, then reset pending error page state.
 347   if (!pending_error_page_info_ || page_type != ERROR_PAGE) {
 348     CancelPendingFetches();
 349   } else {
 350     // If an error load is starting, the resulting error page is autoreloadable.
 351     can_auto_reload_page_ = IsReloadableError(*pending_error_page_info_);
 352   }
 353 }
 354
 355 void NetErrorHelperCore::OnCommitLoad(FrameType frame_type) {
 356   if (frame_type != MAIN_FRAME)
 357     return;
 358
 359   if (committed_error_page_info_ && !pending_error_page_info_ &&
 360       can_auto_reload_page_) {
 361     int reason = committed_error_page_info_->error.reason;
 362     UMA_HISTOGRAM_CUSTOM_ENUMERATION("Net.AutoReload.ErrorAtSuccess",
 363                                      -reason,
 364                                      net::GetAllErrorCodesForUma());
 365     UMA_HISTOGRAM_COUNTS("Net.AutoReload.CountAtSuccess", auto_reload_count_);
 366     if (auto_reload_count_ == 1) {
 367       UMA_HISTOGRAM_CUSTOM_ENUMERATION("Net.AutoReload.ErrorAtFirstSuccess",
 368                                        -reason,
 369                                        net::GetAllErrorCodesForUma());
 370     }
 371   }
 372
 373   committed_error_page_info_.reset(pending_error_page_info_.release());
 374 }
 375
 376 void NetErrorHelperCore::OnFinishLoad(FrameType frame_type) {
 377   if (frame_type != MAIN_FRAME)
 378     return;
 379
 380   if (!committed_error_page_info_) {
 381     auto_reload_count_ = 0;
 382     return;
 383   }
 384
 385   committed_error_page_info_->is_finished_loading = true;
 386
 387   // Only enable stale cache JS bindings if this wasn't a post.
 388   if (!committed_error_page_info_->was_failed_post) {
 389     delegate_->EnableStaleLoadBindings(
 390         committed_error_page_info_->error.unreachableURL);
 391   }
 392
 393   if (committed_error_page_info_->navigation_correction_url.is_valid()) {
 394     // If there is another pending error page load, |fix_url| should have been
 395     // cleared.
 396     DCHECK(!pending_error_page_info_);
 397     DCHECK(!committed_error_page_info_->needs_dns_updates);
 398     delegate_->FetchNavigationCorrections(
 399         committed_error_page_info_->navigation_correction_url,
 400         committed_error_page_info_->navigation_correction_request_body);
 401   } else if (auto_reload_enabled_ &&
 402              IsReloadableError(*committed_error_page_info_)) {
 403     MaybeStartAutoReloadTimer();
 404   }
 405
 406   if (!committed_error_page_info_->needs_dns_updates ||
 407       last_probe_status_ == chrome_common_net::DNS_PROBE_POSSIBLE) {
 408     return;
 409   }
 410   DVLOG(1) << "Error page finished loading; sending saved status.";
 411   UpdateErrorPage();
 412 }
 413
 414 void NetErrorHelperCore::GetErrorHTML(
 415     FrameType frame_type,
 416     const blink::WebURLError& error,
 417     bool is_failed_post,
 418     std::string* error_html) {
 419   if (frame_type == MAIN_FRAME) {
 420     // If navigation corrections were needed before, that should have been
 421     // cancelled earlier by starting a new page load (Which has now failed).
 422     DCHECK(!committed_error_page_info_ ||
 423            !committed_error_page_info_->navigation_correction_url.is_valid());
 424
 425     std::string navigation_correction_request_body;
 426
 427     if (navigation_correction_url_.is_valid() &&
 428         GetFixUrlRequestBody(error, language_, country_code_, api_key_,
 429                              &navigation_correction_request_body)) {
 430       pending_error_page_info_.reset(new ErrorPageInfo(error, is_failed_post));
 431       pending_error_page_info_->navigation_correction_url =
 432           navigation_correction_url_;
 433       pending_error_page_info_->navigation_correction_request_body =
 434           navigation_correction_request_body;
 435       return;
 436     }
 437
 438     // The last probe status needs to be reset if this is a DNS error.  This
 439     // means that if a DNS error page is committed but has not yet finished
 440     // loading, a DNS probe status scheduled to be sent to it may be thrown
 441     // out, but since the new error page should trigger a new DNS probe, it
 442     // will just get the results for the next page load.
 443     if (IsDnsError(error))
 444       last_probe_status_ = chrome_common_net::DNS_PROBE_POSSIBLE;
 445   }
 446
 447   GenerateLocalErrorPage(frame_type, error, is_failed_post,
 448                          scoped_ptr<LocalizedError::ErrorPageParams>(),
 449                          error_html);
 450 }
 451
 452 void NetErrorHelperCore::GenerateLocalErrorPage(
 453     FrameType frame_type,
 454     const blink::WebURLError& error,
 455     bool is_failed_post,
 456     scoped_ptr<LocalizedError::ErrorPageParams> params,
 457     std::string* error_html) {
 458   if (frame_type == MAIN_FRAME) {
 459     pending_error_page_info_.reset(new ErrorPageInfo(error, is_failed_post));
 460     // Skip DNS logic if suggestions were received from a remote server.
 461     if (IsDnsError(error) && !params) {
 462       // This is not strictly necessary, but waiting for a new status to be
 463       // sent as a result of the DidFinishLoading call keeps the histograms
 464       // consistent with older versions of the code, at no real cost.
 465       last_probe_status_ = chrome_common_net::DNS_PROBE_POSSIBLE;
 466
 467       delegate_->GenerateLocalizedErrorPage(
 468           GetUpdatedError(error), is_failed_post, params.Pass(),
 469           error_html);
 470       pending_error_page_info_->needs_dns_updates = true;
 471       return;
 472     }
 473   }
 474
 475   delegate_->GenerateLocalizedErrorPage(error, is_failed_post,
 476                                         params.Pass(), error_html);
 477 }
 478
 479 void NetErrorHelperCore::OnNetErrorInfo(
 480     chrome_common_net::DnsProbeStatus status) {
 481   DCHECK_NE(chrome_common_net::DNS_PROBE_POSSIBLE, status);
 482
 483   last_probe_status_ = status;
 484
 485   if (!committed_error_page_info_ ||
 486       !committed_error_page_info_->needs_dns_updates ||
 487       !committed_error_page_info_->is_finished_loading) {
 488     return;
 489   }
 490
 491   UpdateErrorPage();
 492 }
 493
 494 void NetErrorHelperCore::OnSetNavigationCorrectionInfo(
 495     const GURL& navigation_correction_url,
 496     const std::string& language,
 497     const std::string& country_code,
 498     const std::string& api_key,
 499     const GURL& search_url) {
 500   navigation_correction_url_ = navigation_correction_url;
 501   language_ = language;
 502   country_code_ = country_code;
 503   api_key_ = api_key;
 504   search_url_ = search_url;
 505 }
 506
 507 void NetErrorHelperCore::UpdateErrorPage() {
 508   DCHECK(committed_error_page_info_->needs_dns_updates);
 509   DCHECK(committed_error_page_info_->is_finished_loading);
 510   DCHECK_NE(chrome_common_net::DNS_PROBE_POSSIBLE, last_probe_status_);
 511
 512   UMA_HISTOGRAM_ENUMERATION("DnsProbe.ErrorPageUpdateStatus",
 513                             last_probe_status_,
 514                             chrome_common_net::DNS_PROBE_MAX);
 515   // Every status other than DNS_PROBE_POSSIBLE and DNS_PROBE_STARTED is a
 516   // final status code.  Once one is reached, the page does not need further
 517   // updates.
 518   if (last_probe_status_ != chrome_common_net::DNS_PROBE_STARTED)
 519     committed_error_page_info_->needs_dns_updates = false;
 520
 521   delegate_->UpdateErrorPage(
 522       GetUpdatedError(committed_error_page_info_->error),
 523       committed_error_page_info_->was_failed_post);
 524 }
 525
 526 void NetErrorHelperCore::OnNavigationCorrectionsFetched(
 527     const std::string& corrections,
 528     const std::string& accept_languages,
 529     bool is_rtl) {
 530   // Loading suggestions only starts when a blank error page finishes loading,
 531   // and is cancelled with a new load.
 532   DCHECK(!pending_error_page_info_);
 533   DCHECK(committed_error_page_info_->is_finished_loading);
 534
 535   scoped_ptr<LocalizedError::ErrorPageParams> params(
 536     ParseAdditionalSuggestions(
 537         corrections, GURL(committed_error_page_info_->error.unreachableURL),
 538         search_url_, accept_languages, is_rtl));
 539   std::string error_html;
 540   GenerateLocalErrorPage(MAIN_FRAME,
 541                          committed_error_page_info_->error,
 542                          committed_error_page_info_->was_failed_post,
 543                          params.Pass(),
 544                          &error_html);
 545
 546   // |error_page_info| may have been destroyed by this point, since
 547   // |pending_error_page_info_| was set to a new ErrorPageInfo.
 548
 549   // TODO(mmenke):  Once the new API is in place, look into replacing this
 550   //                double page load by just updating the error page, like DNS
 551   //                probes do.
 552   delegate_->LoadErrorPageInMainFrame(
 553       error_html,
 554       pending_error_page_info_->error.unreachableURL);
 555 }
 556
 557 blink::WebURLError NetErrorHelperCore::GetUpdatedError(
 558     const blink::WebURLError& error) const {
 559   // If a probe didn't run or wasn't conclusive, restore the original error.
 560   if (last_probe_status_ == chrome_common_net::DNS_PROBE_NOT_RUN ||
 561       last_probe_status_ ==
 562           chrome_common_net::DNS_PROBE_FINISHED_INCONCLUSIVE) {
 563     return error;
 564   }
 565
 566   blink::WebURLError updated_error;
 567   updated_error.domain = blink::WebString::fromUTF8(
 568       chrome_common_net::kDnsProbeErrorDomain);
 569   updated_error.reason = last_probe_status_;
 570   updated_error.unreachableURL = error.unreachableURL;
 571   updated_error.staleCopyInCache = error.staleCopyInCache;
 572
 573   return updated_error;
 574 }
 575
 576 void NetErrorHelperCore::Reload() {
 577   if (!committed_error_page_info_) {
 578     return;
 579   }
 580   delegate_->ReloadPage();
 581 }
 582
 583 bool NetErrorHelperCore::MaybeStartAutoReloadTimer() {
 584   if (!committed_error_page_info_ ||
 585       !committed_error_page_info_->is_finished_loading ||
 586       !can_auto_reload_page_ ||
 587       pending_error_page_info_) {
 588     return false;
 589   }
 590
 591   DCHECK(IsReloadableError(*committed_error_page_info_));
 592
 593   if (!online_)
 594     return false;
 595
 596   StartAutoReloadTimer();
 597   return true;
 598 }
 599
 600 void NetErrorHelperCore::StartAutoReloadTimer() {
 601   DCHECK(committed_error_page_info_);
 602   DCHECK(can_auto_reload_page_);
 603   base::TimeDelta delay = GetAutoReloadTime(auto_reload_count_);
 604   auto_reload_count_++;
 605   auto_reload_timer_->Stop();
 606   auto_reload_timer_->Start(FROM_HERE, delay,
 607       base::Bind(&NetErrorHelperCore::Reload,
 608                  base::Unretained(this)));
 609 }
 610
 611 void NetErrorHelperCore::NetworkStateChanged(bool online) {
 612   online_ = online;
 613   if (auto_reload_timer_->IsRunning()) {
 614     DCHECK(committed_error_page_info_);
 615     // If there's an existing timer running, stop it and reset the retry count.
 616     auto_reload_timer_->Stop();
 617     auto_reload_count_ = 0;
 618   }
 619
 620   // If the network state changed to online, maybe start auto-reloading again.
 621   if (online)
 622     MaybeStartAutoReloadTimer();
 623 }
 624
 625 bool NetErrorHelperCore::ShouldSuppressErrorPage(FrameType frame_type,
 626                                                  const GURL& url) {
 627   // Don't suppress child frame errors.
 628   if (frame_type != MAIN_FRAME)
 629     return false;
 630
 631   // If |auto_reload_timer_| is still running, this error page isn't from an
 632   // auto reload.
 633   if (auto_reload_timer_->IsRunning())
 634     return false;
 635
 636   // If there's no committed error page, this error page wasn't from an auto
 637   // reload.
 638   if (!committed_error_page_info_ || !can_auto_reload_page_)
 639     return false;
 640
 641   GURL error_url = committed_error_page_info_->error.unreachableURL;
 642   // TODO(ellyjones): also plumb the error code down to CCRC and check that
 643   if (error_url != url)
 644     return false;
 645
 646   // The first iteration of the timer is started by OnFinishLoad calling
 647   // MaybeStartAutoReloadTimer, but since error pages for subsequent loads are
 648   // suppressed in this function, subsequent iterations of the timer have to be
 649   // started here.
 650   MaybeStartAutoReloadTimer();
 651   return true;
 652 }