1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
|
// Copyright 2008, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "net/base/host_resolver.h"
#include <ws2tcpip.h>
#include <wspiapi.h> // Needed for Win2k compat.
#include "base/string_util.h"
#include "net/base/address_list.h"
#include "net/base/net_errors.h"
#include "net/base/winsock_init.h"
namespace net {
//-----------------------------------------------------------------------------
static int ResolveAddrInfo(const std::string& host, const std::string& port,
struct addrinfo** results) {
struct addrinfo hints = {0};
hints.ai_family = PF_UNSPEC;
hints.ai_flags = AI_ADDRCONFIG;
// Restrict result set to only this socket type to avoid duplicates.
hints.ai_socktype = SOCK_STREAM;
int err = getaddrinfo(host.c_str(), port.c_str(), &hints, results);
return err ? ERR_NAME_NOT_RESOLVED : OK;
}
//-----------------------------------------------------------------------------
struct HostResolver::Request :
public base::RefCountedThreadSafe<HostResolver::Request> {
Request() : error(OK), results(NULL) {
DuplicateHandle(GetCurrentProcess(), GetCurrentThread(),
GetCurrentProcess(), &origin_thread,
0, FALSE, DUPLICATE_SAME_ACCESS);
}
~Request() {
CloseHandle(origin_thread);
}
// Only used on the origin thread (where Resolve was called).
AddressList* addresses;
CompletionCallback* callback;
// Set on the origin thread, read on the worker thread.
std::string host;
std::string port;
HANDLE origin_thread;
// Assigned on the worker thread.
int error;
struct addrinfo* results;
static void CALLBACK ReturnResults(ULONG_PTR param) {
Request* r = reinterpret_cast<Request*>(param);
// The HostResolver may have gone away.
if (r->addresses) {
DCHECK(r->addresses);
r->addresses->Adopt(r->results);
if (r->callback)
r->callback->Run(r->error);
} else if (r->results) {
freeaddrinfo(r->results);
}
r->Release();
}
static DWORD CALLBACK DoLookup(void* param) {
Request* r = static_cast<Request*>(param);
r->error = ResolveAddrInfo(r->host, r->port, &r->results);
if (!QueueUserAPC(ReturnResults, r->origin_thread,
reinterpret_cast<ULONG_PTR>(param))) {
// The origin thread must have gone away.
if (r->results)
freeaddrinfo(r->results);
r->Release();
}
return 0;
}
};
//-----------------------------------------------------------------------------
HostResolver::HostResolver() {
EnsureWinsockInit();
}
HostResolver::~HostResolver() {
if (request_) {
request_->addresses = NULL;
request_->callback = NULL;
}
}
int HostResolver::Resolve(const std::string& hostname, int port,
AddressList* addresses,
CompletionCallback* callback) {
DCHECK(!request_);
const std::string& port_str = IntToString(port);
// Do a synchronous resolution?
if (!callback) {
struct addrinfo* results;
int rv = ResolveAddrInfo(hostname, port_str, &results);
if (rv == OK)
addresses->Adopt(results);
return rv;
}
// Dispatch to worker thread...
request_ = new Request();
request_->host = hostname;
request_->port = port_str;
request_->addresses = addresses;
request_->callback = callback;
// Balanced in Request::ReturnResults (or DoLookup if there is an error).
request_->AddRef();
if (!QueueUserWorkItem(Request::DoLookup, request_, WT_EXECUTELONGFUNCTION)) {
DLOG(ERROR) << "QueueUserWorkItem failed: " << GetLastError();
request_->Release();
request_ = NULL;
return ERR_FAILED;
}
return ERR_IO_PENDING;
}
} // namespace net
|
