src/examples/cpp03/timeouts/blocking_udp_client.cpp | src/examples/cpp11/timeouts/blocking_udp_client.cpp |
⋮ | ⋮ |
1 | // | 1 | // |
2 | //·blocking_udp_client.cpp | 2 | //·blocking_udp_client.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·accompanying | 7 | //·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·"asio/buffer.hpp" | 11 | #include·"asio/buffer.hpp" |
12 | #include·"asio/io_context.hpp" | 12 | #include·"asio/io_context.hpp" |
13 | #include·"asio/ip/udp.hpp" | 13 | #include·"asio/ip/udp.hpp" |
14 | #include·<cstdlib> | 14 | #include·<cstdlib> |
15 | #include·<boost/bind.hpp> | 15 | #include·<functional> |
16 | #include·<iostream> | 16 | #include·<iostream> |
17 | | 17 | |
18 | using·asio::ip::udp; | 18 | using·asio::ip::udp; |
| 19 | using·std::placeholders::_1; |
| 20 | using·std::placeholders::_2; |
19 | | 21 | |
20 | //---------------------------------------------------------------------- | 22 | //---------------------------------------------------------------------- |
21 | | 23 | |
22 | // | 24 | // |
23 | //·This·class·manages·socket·timeouts·by·running·the·io_context·using·the·timed | 25 | //·This·class·manages·socket·timeouts·by·running·the·io_context·using·the·timed |
24 | //·io_context::run_for()·member·function.·Each·asynchronous·operation·is·given | 26 | //·io_context::run_for()·member·function.·Each·asynchronous·operation·is·given |
25 | //·a·timeout·within·which·it·must·complete.·The·socket·operations·themselves | 27 | //·a·timeout·within·which·it·must·complete.·The·socket·operations·themselves |
26 | //·use·boost::bind·to·specify·the·completion·handler: | 28 | //·use·std::bind·to·specify·the·completion·handler: |
27 | // | 29 | // |
28 | //···+---------------+ | 30 | //···+---------------+ |
29 | //···|···············| | 31 | //···|···············| |
30 | //···|····receive····| | 32 | //···|····receive····| |
31 | //···|···············| | 33 | //···|···············| |
32 | //···+---------------+ | 34 | //···+---------------+ |
33 | //···········| | 35 | //···········| |
34 | //··async_-··|····+----------------+ | 36 | //··async_-··|····+----------------+ |
35 | //·receive()·|····|················| | 37 | //·receive()·|····|················| |
36 | //···········+--->|·handle_receive·| | 38 | //···········+--->|·handle_receive·| |
37 | //················|················| | 39 | //················|················| |
38 | //················+----------------+ | 40 | //················+----------------+ |
39 | // | 41 | // |
40 | //·For·a·given·socket·operation,·the·client·object·runs·the·io_context·to·block | 42 | //·For·a·given·socket·operation,·the·client·object·runs·the·io_context·to·block |
41 | //·thread·execution·until·the·operation·completes·or·the·timeout·is·reached.·If | 43 | //·thread·execution·until·the·operation·completes·or·the·timeout·is·reached.·If |
42 | //·the·io_context::run_for()·function·times·out,·the·socket·is·closed·and·the | 44 | //·the·io_context::run_for()·function·times·out,·the·socket·is·closed·and·the |
43 | //·outstanding·asynchronous·operation·is·cancelled. | 45 | //·outstanding·asynchronous·operation·is·cancelled. |
44 | // | 46 | // |
45 | class·client | 47 | class·client |
46 | { | 48 | { |
47 | public: | 49 | public: |
48 | ··client(const·udp::endpoint&·listen_endpoint) | 50 | ··client(const·udp::endpoint&·listen_endpoint) |
49 | ····:·socket_(io_context_,·listen_endpoint) | 51 | ····:·socket_(io_context_,·listen_endpoint) |
50 | ··{ | 52 | ··{ |
51 | ··} | 53 | ··} |
52 | | 54 | |
53 | ··std::size_t·receive(const·asio::mutable_buffer&·buffer, | 55 | ··std::size_t·receive(const·asio::mutable_buffer&·buffer, |
54 | ······asio::chrono::steady_clock::duration·timeout, | 56 | ······std::chrono::steady_clock::duration·timeout, |
55 | ······asio::error_code&·ec) | 57 | ······std::error_code&·error) |
56 | ··{ | 58 | ··{ |
57 | ····//·Start·the·asynchronous·operation.·The·handle_receive·function·used·as·a | 59 | ····//·Start·the·asynchronous·operation.·The·handle_receive·function·used·as·a |
58 | ····//·callback·will·update·the·ec·and·length·variables. | 60 | ····//·callback·will·update·the·error·and·length·variables. |
59 | ····std::size_t·length·=·0; | 61 | ····std::size_t·length·=·0; |
60 | ····socket_.async_receive(asio::buffer(buffer), | 62 | ····socket_.async_receive(asio::buffer(buffer), |
61 | ········boost::bind(&client::handle_receive,·_1,·_2,·&ec,·&length)); | 63 | ········std::bind(&client::handle_receive,·_1,·_2,·&error,·&length)); |
62 | | 64 | |
63 | ····//·Run·the·operation·until·it·completes,·or·until·the·timeout. | 65 | ····//·Run·the·operation·until·it·completes,·or·until·the·timeout. |
64 | ····run(timeout); | 66 | ····run(timeout); |
65 | | 67 | |
66 | ····return·length; | 68 | ····return·length; |
67 | ··} | 69 | ··} |
68 | | 70 | |
69 | private: | 71 | private: |
70 | ··void·run(asio::chrono::steady_clock::duration·timeout) | 72 | ··void·run(std::chrono::steady_clock::duration·timeout) |
71 | ··{ | 73 | ··{ |
72 | ····//·Restart·the·io_context,·as·it·may·have·been·left·in·the·"stopped"·state | 74 | ····//·Restart·the·io_context,·as·it·may·have·been·left·in·the·"stopped"·state |
73 | ····//·by·a·previous·operation. | 75 | ····//·by·a·previous·operation. |
74 | ····io_context_.restart(); | 76 | ····io_context_.restart(); |
75 | | 77 | |
76 | ····//·Block·until·the·asynchronous·operation·has·completed,·or·timed·out.·If | 78 | ····//·Block·until·the·asynchronous·operation·has·completed,·or·timed·out.·If |
77 | ····//·the·pending·asynchronous·operation·is·a·composed·operation,·the·deadline | 79 | ····//·the·pending·asynchronous·operation·is·a·composed·operation,·the·deadline |
78 | ····//·applies·to·the·entire·operation,·rather·than·individual·operations·on | 80 | ····//·applies·to·the·entire·operation,·rather·than·individual·operations·on |
79 | ····//·the·socket. | 81 | ····//·the·socket. |
80 | ····io_context_.run_for(timeout); | 82 | ····io_context_.run_for(timeout); |
81 | | 83 | |
82 | ····//·If·the·asynchronous·operation·completed·successfully·then·the·io_context | 84 | ····//·If·the·asynchronous·operation·completed·successfully·then·the·io_context |
83 | ····//·would·have·been·stopped·due·to·running·out·of·work.·If·it·was·not | 85 | ····//·would·have·been·stopped·due·to·running·out·of·work.·If·it·was·not |
84 | ····//·stopped,·then·the·io_context::run_for·call·must·have·timed·out. | 86 | ····//·stopped,·then·the·io_context::run_for·call·must·have·timed·out. |
85 | ····if·(!io_context_.stopped()) | 87 | ····if·(!io_context_.stopped()) |
86 | ····{ | 88 | ····{ |
87 | ······//·Cancel·the·outstanding·asynchronous·operation. | 89 | ······//·Cancel·the·outstanding·asynchronous·operation. |
88 | ······socket_.cancel(); | 90 | ······socket_.cancel(); |
89 | | 91 | |
90 | ······//·Run·the·io_context·again·until·the·operation·completes. | 92 | ······//·Run·the·io_context·again·until·the·operation·completes. |
91 | ······io_context_.run(); | 93 | ······io_context_.run(); |
92 | ····} | 94 | ····} |
93 | ··} | 95 | ··} |
94 | | 96 | |
95 | ··static·void·handle_receive( | 97 | ··static·void·handle_receive( |
96 | ······const·asio::error_code&·ec,·std::size_t·length, | 98 | ······const·std::error_code&·error,·std::size_t·length, |
97 | ······asio::error_code*·out_ec,·std::size_t*·out_length) | 99 | ······std::error_code*·out_error,·std::size_t*·out_length) |
98 | ··{ | 100 | ··{ |
99 | ····*out_ec·=·ec; | 101 | ····*out_error·=·error; |
100 | ····*out_length·=·length; | 102 | ····*out_length·=·length; |
101 | ··} | 103 | ··} |
102 | | 104 | |
103 | private: | 105 | private: |
104 | ··asio::io_context·io_context_; | 106 | ··asio::io_context·io_context_; |
105 | ··udp::socket·socket_; | 107 | ··udp::socket·socket_; |
106 | }; | 108 | }; |
107 | | 109 | |
108 | //---------------------------------------------------------------------- | 110 | //---------------------------------------------------------------------- |
109 | | 111 | |
110 | int·main(int·argc,·char*·argv[]) | 112 | int·main(int·argc,·char*·argv[]) |
111 | { | 113 | { |
112 | ··try | 114 | ··try |
113 | ··{ | 115 | ··{ |
114 | ····using·namespace·std;·//·For·atoi. | 116 | ····using·namespace·std;·//·For·atoi. |
115 | | 117 | |
116 | ····if·(argc·!=·3) | 118 | ····if·(argc·!=·3) |
117 | ····{ | 119 | ····{ |
118 | ······std::cerr·<<·"Usage:·blocking_udp_client·<listen_addr>·<listen_port>\n"; | 120 | ······std::cerr·<<·"Usage:·blocking_udp_client·<listen_addr>·<listen_port>\n"; |
119 | ······return·1; | 121 | ······return·1; |
120 | ····} | 122 | ····} |
121 | | 123 | |
122 | ····udp::endpoint·listen_endpoint( | 124 | ····udp::endpoint·listen_endpoint( |
123 | ········asio::ip::make_address(argv[1]), | 125 | ········asio::ip::make_address(argv[1]), |
124 | ········std::atoi(argv[2])); | 126 | ········std::atoi(argv[2])); |
125 | | 127 | |
126 | ····client·c(listen_endpoint); | 128 | ····client·c(listen_endpoint); |
127 | | 129 | |
128 | ····for·(;;) | 130 | ····for·(;;) |
129 | ····{ | 131 | ····{ |
130 | ······char·data[1024]; | 132 | ······char·data[1024]; |
131 | ······asio::error_code·ec; | 133 | ······std::error_code·error; |
132 | ······std::size_t·n·=·c.receive(asio::buffer(data), | 134 | ······std::size_t·n·=·c.receive(asio::buffer(data), |
133 | ··········asio::chrono::seconds(10),·ec); | 135 | ··········std::chrono::seconds(10),·error); |
134 | | 136 | |
135 | ······if·(ec) | 137 | ······if·(error) |
136 | ······{ | 138 | ······{ |
137 | ········std::cout·<<·"Receive·error:·"·<<·ec.message()·<<·"\n";· | 139 | ········std::cout·<<·"Receive·error:·"·<<·error.message()·<<·"\n";· |
138 | ······} | 140 | ······} |
139 | ······else | 141 | ······else |
140 | ······{ | 142 | ······{ |
141 | ········std::cout·<<·"Received:·"; | 143 | ········std::cout·<<·"Received:·"; |
142 | ········std::cout.write(data,·n); | 144 | ········std::cout.write(data,·n); |
143 | ········std::cout·<<·"\n"; | 145 | ········std::cout·<<·"\n"; |
144 | ······} | 146 | ······} |
145 | ····} | 147 | ····} |
146 | ··} | 148 | ··} |
147 | ··catch·(std::exception&·e) | 149 | ··catch·(std::exception&·e) |
148 | ··{ | 150 | ··{ |
149 | ····std::cerr·<<·"Exception:·"·<<·e.what()·<<·"\n"; | 151 | ····std::cerr·<<·"Exception:·"·<<·e.what()·<<·"\n"; |
150 | ··} | 152 | ··} |
151 | | 153 | |
152 | ··return·0; | 154 | ··return·0; |
153 | } | 155 | } |