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// Copyright (c) 2011 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 "chrome/browser/net/preconnect.h"
#include "base/logging.h"
#include "base/metrics/histogram.h"
#include "chrome/browser/profiles/profile.h"
#include "content/browser/browser_thread.h"
#include "net/base/net_log.h"
#include "net/base/ssl_config_service.h"
#include "net/http/http_network_session.h"
#include "net/http/http_request_info.h"
#include "net/http/http_stream_factory.h"
#include "net/http/http_transaction_factory.h"
#include "net/url_request/url_request_context.h"
#include "net/url_request/url_request_context_getter.h"
namespace chrome_browser_net {
void PreconnectOnUIThread(
const GURL& url,
UrlInfo::ResolutionMotivation motivation,
int count) {
// Prewarm connection to Search URL.
BrowserThread::PostTask(
BrowserThread::IO,
FROM_HERE,
NewRunnableFunction(PreconnectOnIOThread, url, motivation,
count));
return;
}
void PreconnectOnIOThread(
const GURL& url,
UrlInfo::ResolutionMotivation motivation,
int count) {
net::URLRequestContextGetter* getter = Profile::GetDefaultRequestContext();
if (!getter)
return;
if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
LOG(DFATAL) << "This must be run only on the IO thread.";
return;
}
// We are now commited to doing the async preconnection call.
UMA_HISTOGRAM_ENUMERATION("Net.PreconnectMotivation", motivation,
UrlInfo::MAX_MOTIVATED);
net::URLRequestContext* context = getter->GetURLRequestContext();
net::HttpTransactionFactory* factory = context->http_transaction_factory();
net::HttpNetworkSession* session = factory->GetSession();
net::HttpRequestInfo request_info;
request_info.url = url;
request_info.method = "GET";
request_info.extra_headers.SetHeader(net::HttpRequestHeaders::kUserAgent,
context->GetUserAgent(url));
// It almost doesn't matter whether we use net::LOWEST or net::HIGHEST
// priority here, as we won't make a request, and will surrender the created
// socket to the pool as soon as we can. However, we would like to mark the
// speculative socket as such, and IF we use a net::LOWEST priority, and if
// a navigation asked for a socket (after us) then it would get our socket,
// and we'd get its later-arriving socket, which might make us record that
// the speculation didn't help :-/. By using net::HIGHEST, we ensure that
// a socket is given to us if "we asked first" and this allows us to mark it
// as speculative, and better detect stats (if it gets used).
// TODO(jar): histogram to see how often we accidentally use a previously-
// unused socket, when a previously used socket was available.
request_info.priority = net::HIGHEST;
// Translate the motivation from UrlRequest motivations to HttpRequest
// motivations.
switch (motivation) {
case UrlInfo::OMNIBOX_MOTIVATED:
request_info.motivation = net::HttpRequestInfo::OMNIBOX_MOTIVATED;
break;
case UrlInfo::LEARNED_REFERAL_MOTIVATED:
request_info.motivation = net::HttpRequestInfo::PRECONNECT_MOTIVATED;
break;
case UrlInfo::SELF_REFERAL_MOTIVATED:
case UrlInfo::EARLY_LOAD_MOTIVATED:
request_info.motivation = net::HttpRequestInfo::EARLY_LOAD_MOTIVATED;
break;
default:
// Other motivations should never happen here.
NOTREACHED();
break;
}
// Setup the SSL Configuration.
net::SSLConfig ssl_config;
session->ssl_config_service()->GetSSLConfig(&ssl_config);
if (session->http_stream_factory()->next_protos())
ssl_config.next_protos = *session->http_stream_factory()->next_protos();
// All preconnects should perform EV certificate verification.
ssl_config.verify_ev_cert = true;
net::HttpStreamFactory* http_stream_factory = session->http_stream_factory();
http_stream_factory->PreconnectStreams(
count, request_info, ssl_config, net::BoundNetLog());
}
} // namespace chrome_browser_net
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