src/​examples/​cpp03/​echo/​async_udp_echo_server​.​cppsrc/​examples/​cpp11/​echo/​async_udp_echo_server​.​cpp
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2 /​/​·​async_udp_echo_server​.​cpp2 /​/​·​async_udp_echo_server​.​cpp
3 /​/​·​~~~~~~~~~~~~~~~~~~~~~​~~~~3 /​/​·​~~~~~~~~~~~~~~~~~~~~~​~~~~
4 /​/​4 /​/​
5 /​/​·​Copyright·​(c)​·​2003-​2018·​Christopher·​M.​·​Kohlhoff·​(chris·​at·​kohlhoff·​dot·​com)​5 /​/​·​Copyright·​(c)​·​2003-​2018·​Christopher·​M.​·​Kohlhoff·​(chris·​at·​kohlhoff·​dot·​com)​
6 /​/​6 /​/​
7 /​/​·​Distributed·​under·​the·​Boost·​Software·​License,​·​Version·​1.​0.​·​(See·​accompanying7 /​/​·​Distributed·​under·​the·​Boost·​Software·​License,​·​Version·​1.​0.​·​(See·​accompanying
8 /​/​·​file·​LICENSE_1_0.​txt·​or·​copy·​at·​http:​/​/​www.​boost.​org/​LICENSE_1_0.​txt)​8 /​/​·​file·​LICENSE_1_0.​txt·​or·​copy·​at·​http:​/​/​www.​boost.​org/​LICENSE_1_0.​txt)​
9 /​/​9 /​/​
10 10
11 #include·​<cstdlib>11 #include·​<cstdlib>
12 #include·​<iostream>12 #include·​<iostream>
13 #include·​<boost/​bind.​hpp>
14 #include·​"asio.​hpp"13 #include·​"asio.​hpp"
15 14
16 using·​asio:​:​ip:​:​udp;​15 using·​asio:​:​ip:​:​udp;​
17 16
18 class·​server17 class·​server
19 {18 {
20 public:​19 public:​
21 ··​server(asio:​:​io_context&·​io_context,​·​short·​port)​20 ··​server(asio:​:​io_context&·​io_context,​·​short·​port)​
22 ····​:​·​socket_(io_context,​·​udp:​:​endpoint(udp:​:​v4()​,​·​port)​)​21 ····​:​·​socket_(io_context,​·​udp:​:​endpoint(udp:​:​v4()​,​·​port)​)​
23 ··​{22 ··​{
24 ····socket_.​async_receive_from(23 ····do_receive()​;​
25 ········asio:​:​buffer(data_,​·max_length)​,​·sender_endpoint_,​
26 ········boost:​:​bind(&server:​:​handle_receive_from,​·this,​
27 ··········asio:​:​placeholders:​:​error,​
28 ··········asio:​:​placeholders:​:​bytes_transferred)​)​;​
29 ··​}24 ··​}
30 25
31 ··​void·handle_receive_from(c​onst·asio:​:​error_code&·error,​26 ··​void·​do_receive()​
32 ······size_t·bytes_recvd)​
33 ··​{27 ··​{
34 ····if·(!error·&&·bytes_recvd·>·0)​28 ····socket_.​async_receive_from(
35 ····{29 ········asio:​:​buffer(data_,​·max_length)​,​·sender_endpoint_,​
36 ······​socket_.​async_send_to(30 ········[this](std:​:​error_code·ec,​·std:​:​size_t·bytes_recvd)​
37 ··········asio:​:​buffer(data_,​·bytes_recvd)​,​·sender_endpoint_,​31 ········{
38 ··········boost:​:​bind(&server:​:​handle_send_to,​·this,​32 ··········​if·(!ec·&&·bytes_recvd·>·0)​
39 ············asio:​:​placeholders:​:​error,​33 ··········{
40 ············asio:​:​placeholders:​:​bytes_transferred)​)​;​34 ············do_send(bytes_recvd)​;​
41 ····​}35 ··········​}
42 ····​else36 ··········​else
43 ····​{37 ··········​{
44 ······socket_.​async_receive_from(38 ············do_receive()​;​
45 ··········asio:​:​buffer(data_,​·max_length)​,​·sender_endpoint_,​39 ··········}
46 ··········boost:​:​bind(&server:​:​handle_receive_from,​·this,​40 ········})​;​
47 ············asio:​:​placeholders:​:​error,​
48 ············asio:​:​placeholders:​:​bytes_transferred)​)​;​
49 ····}
50 ··​}41 ··​}
51 42
52 ··​void·handle_send_to(const·asio:​:​error_code&·/​*error*/​,​43 ··​void·​do_send(std:​:​size_t·length)​
53 ······size_t·/​*bytes_sent*/​)​
54 ··​{44 ··​{
55 ····​socket_.​async_receive_from(45 ····​socket_.​async_send_to(
56 ········​asio:​:​buffer(data_,​·max_length)​,​·​sender_endpoint_,​46 ········​asio:​:​buffer(data_,​·​length)​,​·​sender_endpoint_,​
57 ········boost:​:​bind(&server:​:​handle_receive_from,​·this,​47 ········[this](std:​:​error_code·/​*ec*/​,​·std:​:​size_t·/​*bytes_sent*/​)​
58 ··········asio:​:​placeholders:​:​error,​48 ········{
59 ··········asio:​:​placeholders:​:​bytes_transferred)​)​;​49 ··········​do_receive()​;​
50 ········​})​;​
60 ··​}51 ··​}
61 52
62 private:​53 private:​
63 ··​udp:​:​socket·​socket_;​54 ··​udp:​:​socket·​socket_;​
64 ··​udp:​:​endpoint·​sender_endpoint_;​55 ··​udp:​:​endpoint·​sender_endpoint_;​
65 ··​enum·​{·​max_length·​=·​1024·​};​56 ··​enum·​{·​max_length·​=·​1024·​};​
66 ··​char·​data_[max_length];​57 ··​char·​data_[max_length];​
67 };​58 };​
68 59
69 int·​main(int·​argc,​·​char*·​argv[])​60 int·​main(int·​argc,​·​char*·​argv[])​
70 {61 {
71 ··​try62 ··​try
72 ··​{63 ··​{
73 ····​if·​(argc·​!=·​2)​64 ····​if·​(argc·​!=·​2)​
74 ····​{65 ····​{
75 ······​std:​:​cerr·​<<·​"Usage:​·​async_udp_echo_server​·​<port>\n";​66 ······​std:​:​cerr·​<<·​"Usage:​·​async_udp_echo_server​·​<port>\n";​
76 ······​return·​1;​67 ······​return·​1;​
77 ····​}68 ····​}
78 69
79 ····​asio:​:​io_context·​io_context;​70 ····​asio:​:​io_context·​io_context;​
80 71
81 ····using·namespace·​std;​·/​/​·For·atoi.​72 ····server·s(io_context,​·​std:​:​atoi(argv[1])​)​;​
82 ····server·s(io_context,​·atoi(argv[1])​)​;​
83 73
84 ····​io_context.​run()​;​74 ····​io_context.​run()​;​
85 ··​}75 ··​}
86 ··​catch·​(std:​:​exception&·​e)​76 ··​catch·​(std:​:​exception&·​e)​
87 ··​{77 ··​{
88 ····​std:​:​cerr·​<<·​"Exception:​·​"·​<<·​e.​what()​·​<<·​"\n";​78 ····​std:​:​cerr·​<<·​"Exception:​·​"·​<<·​e.​what()​·​<<·​"\n";​
89 ··​}79 ··​}
90 80
91 ··​return·​0;​81 ··​return·​0;​
92 }82 }