1// Copyright 2014 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 "extensions/browser/api/dns/dns_api.h"
6
7#include "base/bind.h"
8#include "base/values.h"
9#include "content/public/browser/browser_context.h"
10#include "content/public/browser/browser_thread.h"
11#include "content/public/browser/resource_context.h"
12#include "extensions/browser/api/dns/host_resolver_wrapper.h"
13#include "extensions/common/api/dns.h"
14#include "net/base/host_port_pair.h"
15#include "net/base/net_errors.h"
16#include "net/base/net_log.h"
17
18using content::BrowserThread;
19using extensions::core_api::dns::ResolveCallbackResolveInfo;
20
21namespace Resolve = extensions::core_api::dns::Resolve;
22
23namespace extensions {
24
25DnsResolveFunction::DnsResolveFunction()
26    : resource_context_(NULL),
27      response_(false),
28      request_handle_(new net::HostResolver::RequestHandle()),
29      addresses_(new net::AddressList) {}
30
31DnsResolveFunction::~DnsResolveFunction() {}
32
33bool DnsResolveFunction::RunAsync() {
34  scoped_ptr<Resolve::Params> params(Resolve::Params::Create(*args_));
35  EXTENSION_FUNCTION_VALIDATE(params.get());
36
37  hostname_ = params->hostname;
38  resource_context_ = browser_context()->GetResourceContext();
39
40  bool result = BrowserThread::PostTask(
41      BrowserThread::IO,
42      FROM_HERE,
43      base::Bind(&DnsResolveFunction::WorkOnIOThread, this));
44  DCHECK(result);
45  return true;
46}
47
48void DnsResolveFunction::WorkOnIOThread() {
49  DCHECK_CURRENTLY_ON(BrowserThread::IO);
50
51  net::HostResolver* host_resolver =
52      HostResolverWrapper::GetInstance()->GetHostResolver(resource_context_);
53  DCHECK(host_resolver);
54
55  // Yes, we are passing zero as the port. There are some interesting but not
56  // presently relevant reasons why HostResolver asks for the port of the
57  // hostname you'd like to resolve, even though it doesn't use that value in
58  // determining its answer.
59  net::HostPortPair host_port_pair(hostname_, 0);
60
61  net::HostResolver::RequestInfo request_info(host_port_pair);
62  int resolve_result = host_resolver->Resolve(
63      request_info,
64      net::DEFAULT_PRIORITY,
65      addresses_.get(),
66      base::Bind(&DnsResolveFunction::OnLookupFinished, this),
67      request_handle_.get(),
68      net::BoundNetLog());
69
70  // Balanced in OnLookupFinished.
71  AddRef();
72
73  if (resolve_result != net::ERR_IO_PENDING)
74    OnLookupFinished(resolve_result);
75}
76
77void DnsResolveFunction::RespondOnUIThread() {
78  DCHECK_CURRENTLY_ON(BrowserThread::UI);
79  SendResponse(response_);
80}
81
82void DnsResolveFunction::OnLookupFinished(int resolve_result) {
83  scoped_ptr<ResolveCallbackResolveInfo> resolve_info(
84      new ResolveCallbackResolveInfo());
85  resolve_info->result_code = resolve_result;
86  if (resolve_result == net::OK) {
87    DCHECK(!addresses_->empty());
88    resolve_info->address.reset(
89        new std::string(addresses_->front().ToStringWithoutPort()));
90  }
91  results_ = Resolve::Results::Create(*resolve_info);
92  response_ = true;
93
94  bool post_task_result = BrowserThread::PostTask(
95      BrowserThread::UI,
96      FROM_HERE,
97      base::Bind(&DnsResolveFunction::RespondOnUIThread, this));
98  DCHECK(post_task_result);
99
100  Release();  // Added in WorkOnIOThread().
101}
102
103}  // namespace extensions
104