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// Copyright (c) 2012 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.
#include "content/browser/loader/throttling_resource_handler.h"
#include "content/browser/loader/resource_request_info_impl.h"
#include "content/public/browser/resource_throttle.h"
#include "content/public/common/resource_response.h"
#include "net/url_request/url_request.h"
namespace content {
ThrottlingResourceHandler::ThrottlingResourceHandler(
scoped_ptr<ResourceHandler> next_handler,
net::URLRequest* request,
ScopedVector<ResourceThrottle> throttles)
: LayeredResourceHandler(request, next_handler.Pass()),
deferred_stage_(DEFERRED_NONE),
throttles_(throttles.Pass()),
next_index_(0),
cancelled_by_resource_throttle_(false) {
for (size_t i = 0; i < throttles_.size(); ++i) {
throttles_[i]->set_controller(this);
// Throttles must have a name, as otherwise, bugs where a throttle fails
// to resume a request can be very difficult to debug.
DCHECK(throttles_[i]->GetNameForLogging());
}
}
ThrottlingResourceHandler::~ThrottlingResourceHandler() {
}
bool ThrottlingResourceHandler::OnRequestRedirected(const GURL& new_url,
ResourceResponse* response,
bool* defer) {
DCHECK(!cancelled_by_resource_throttle_);
*defer = false;
while (next_index_ < throttles_.size()) {
int index = next_index_;
throttles_[index]->WillRedirectRequest(new_url, defer);
next_index_++;
if (cancelled_by_resource_throttle_)
return false;
if (*defer) {
OnRequestDefered(index);
deferred_stage_ = DEFERRED_REDIRECT;
deferred_url_ = new_url;
deferred_response_ = response;
return true; // Do not cancel.
}
}
next_index_ = 0; // Reset for next time.
return next_handler_->OnRequestRedirected(new_url, response, defer);
}
bool ThrottlingResourceHandler::OnWillStart(const GURL& url, bool* defer) {
DCHECK(!cancelled_by_resource_throttle_);
*defer = false;
while (next_index_ < throttles_.size()) {
int index = next_index_;
throttles_[index]->WillStartRequest(defer);
next_index_++;
if (cancelled_by_resource_throttle_)
return false;
if (*defer) {
OnRequestDefered(index);
deferred_stage_ = DEFERRED_START;
deferred_url_ = url;
return true; // Do not cancel.
}
}
next_index_ = 0; // Reset for next time.
return next_handler_->OnWillStart(url, defer);
}
bool ThrottlingResourceHandler::OnBeforeNetworkStart(const GURL& url,
bool* defer) {
DCHECK(!cancelled_by_resource_throttle_);
*defer = false;
while (next_index_ < throttles_.size()) {
int index = next_index_;
throttles_[index]->OnBeforeNetworkStart(defer);
next_index_++;
if (cancelled_by_resource_throttle_)
return false;
if (*defer) {
OnRequestDefered(index);
deferred_stage_ = DEFERRED_NETWORK_START;
deferred_url_ = url;
return true; // Do not cancel.
}
}
next_index_ = 0; // Reset for next time.
return next_handler_->OnBeforeNetworkStart(url, defer);
}
bool ThrottlingResourceHandler::OnResponseStarted(ResourceResponse* response,
bool* defer) {
DCHECK(!cancelled_by_resource_throttle_);
while (next_index_ < throttles_.size()) {
int index = next_index_;
throttles_[index]->WillProcessResponse(defer);
next_index_++;
if (cancelled_by_resource_throttle_)
return false;
if (*defer) {
OnRequestDefered(index);
deferred_stage_ = DEFERRED_RESPONSE;
deferred_response_ = response;
return true; // Do not cancel.
}
}
next_index_ = 0; // Reset for next time.
return next_handler_->OnResponseStarted(response, defer);
}
void ThrottlingResourceHandler::Cancel() {
cancelled_by_resource_throttle_ = true;
controller()->Cancel();
}
void ThrottlingResourceHandler::CancelAndIgnore() {
cancelled_by_resource_throttle_ = true;
controller()->CancelAndIgnore();
}
void ThrottlingResourceHandler::CancelWithError(int error_code) {
cancelled_by_resource_throttle_ = true;
controller()->CancelWithError(error_code);
}
void ThrottlingResourceHandler::Resume() {
DCHECK(!cancelled_by_resource_throttle_);
DeferredStage last_deferred_stage = deferred_stage_;
deferred_stage_ = DEFERRED_NONE;
// Clear information about the throttle that delayed the request.
request()->LogUnblocked();
switch (last_deferred_stage) {
case DEFERRED_NONE:
NOTREACHED();
break;
case DEFERRED_START:
ResumeStart();
break;
case DEFERRED_NETWORK_START:
ResumeNetworkStart();
break;
case DEFERRED_REDIRECT:
ResumeRedirect();
break;
case DEFERRED_RESPONSE:
ResumeResponse();
break;
}
}
void ThrottlingResourceHandler::ResumeStart() {
DCHECK(!cancelled_by_resource_throttle_);
GURL url = deferred_url_;
deferred_url_ = GURL();
bool defer = false;
if (!OnWillStart(url, &defer)) {
controller()->Cancel();
} else if (!defer) {
controller()->Resume();
}
}
void ThrottlingResourceHandler::ResumeNetworkStart() {
DCHECK(!cancelled_by_resource_throttle_);
GURL url = deferred_url_;
deferred_url_ = GURL();
bool defer = false;
if (!OnBeforeNetworkStart(url, &defer)) {
controller()->Cancel();
} else if (!defer) {
controller()->Resume();
}
}
void ThrottlingResourceHandler::ResumeRedirect() {
DCHECK(!cancelled_by_resource_throttle_);
GURL new_url = deferred_url_;
deferred_url_ = GURL();
scoped_refptr<ResourceResponse> response;
deferred_response_.swap(response);
bool defer = false;
if (!OnRequestRedirected(new_url, response.get(), &defer)) {
controller()->Cancel();
} else if (!defer) {
controller()->Resume();
}
}
void ThrottlingResourceHandler::ResumeResponse() {
DCHECK(!cancelled_by_resource_throttle_);
scoped_refptr<ResourceResponse> response;
deferred_response_.swap(response);
bool defer = false;
if (!OnResponseStarted(response.get(), &defer)) {
controller()->Cancel();
} else if (!defer) {
controller()->Resume();
}
}
void ThrottlingResourceHandler::OnRequestDefered(int throttle_index) {
request()->LogBlockedBy(throttles_[throttle_index]->GetNameForLogging());
}
} // namespace content
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