// 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.
#ifndef NET_PROXY_PROXY_RESOLVER_V8_H_
#define NET_PROXY_PROXY_RESOLVER_V8_H_
#include "base/compiler_specific.h"
#include "base/memory/scoped_ptr.h"
#include "net/base/net_export.h"
#include "net/proxy/proxy_resolver.h"
namespace v8 {
class HeapStatistics;
class Isolate;
} // namespace v8
namespace net {
// Implementation of ProxyResolver that uses V8 to evaluate PAC scripts.
//
// ----------------------------------------------------------------------------
// !!! Important note on threading model:
// ----------------------------------------------------------------------------
// There can be only one instance of V8 running at a time. To enforce this
// constraint, ProxyResolverV8 holds a v8::Locker during execution. Therefore
// it is OK to run multiple instances of ProxyResolverV8 on different threads,
// since only one will be running inside V8 at a time.
//
// It is important that *ALL* instances of V8 in the process be using
// v8::Locker. If not there can be race conditions between the non-locked V8
// instances and the locked V8 instances used by ProxyResolverV8 (assuming they
// run on different threads).
//
// This is the case with the V8 instance used by chromium's renderer -- it runs
// on a different thread from ProxyResolver (renderer thread vs PAC thread),
// and does not use locking since it expects to be alone.
class NET_EXPORT_PRIVATE ProxyResolverV8 : public ProxyResolver {
public:
// Interface for the javascript bindings.
class NET_EXPORT_PRIVATE JSBindings {
public:
enum ResolveDnsOperation {
DNS_RESOLVE,
DNS_RESOLVE_EX,
MY_IP_ADDRESS,
MY_IP_ADDRESS_EX,
};
JSBindings() {}
// Handler for "dnsResolve()", "dnsResolveEx()", "myIpAddress()",
// "myIpAddressEx()". Returns true on success and fills |*output| with the
// result. If |*terminate| is set to true, then the script execution will
// be aborted. Note that termination may not happen right away.
virtual bool ResolveDns(const std::string& host,
ResolveDnsOperation op,
std::string* output,
bool* terminate) = 0;
// Handler for "alert(message)"
virtual void Alert(const base::string16& message) = 0;
// Handler for when an error is encountered. |line_number| may be -1
// if a line number is not applicable to this error.
virtual void OnError(int line_number, const base::string16& error) = 0;
protected:
virtual ~JSBindings() {}
};
// Constructs a ProxyResolverV8.
ProxyResolverV8();
virtual ~ProxyResolverV8();
JSBindings* js_bindings() const { return js_bindings_; }
void set_js_bindings(JSBindings* js_bindings) { js_bindings_ = js_bindings; }
// ProxyResolver implementation:
virtual int GetProxyForURL(const GURL& url,
ProxyInfo* results,
const net::CompletionCallback& /*callback*/,
RequestHandle* /*request*/,
const BoundNetLog& net_log) OVERRIDE;
virtual void CancelRequest(RequestHandle request) OVERRIDE;
virtual LoadState GetLoadState(RequestHandle request) const OVERRIDE;
virtual void CancelSetPacScript() OVERRIDE;
virtual int SetPacScript(
const scoped_refptr<ProxyResolverScriptData>& script_data,
const net::CompletionCallback& /*callback*/) OVERRIDE;
// Remember the default Isolate, must be called from the main thread. This
// hack can be removed when the "default Isolate" concept is gone.
static void RememberDefaultIsolate();
#if defined(OS_WIN)
// Create an isolate to use for the proxy resolver. Until the "default
// Isolate" concept is gone, it is preferable to invoke
// RememberDefaultIsolate() as creating a new Isolate in additional to the
// default Isolate will waste a few MB of memory and the runtime it took to
// create the default Isolate.
static void CreateIsolate();
#endif
static v8::Isolate* GetDefaultIsolate();
// Get total/ued heap memory usage of all v8 instances used by the proxy
// resolver.
static size_t GetTotalHeapSize();
static size_t GetUsedHeapSize();
private:
static v8::Isolate* g_default_isolate_;
// Context holds the Javascript state for the most recently loaded PAC
// script. It corresponds with the data from the last call to
// SetPacScript().
class Context;
scoped_ptr<Context> context_;
JSBindings* js_bindings_;
DISALLOW_COPY_AND_ASSIGN(ProxyResolverV8);
};
} // namespace net
#endif // NET_PROXY_PROXY_RESOLVER_V8_H_