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| <div class="title">multithreaded_client_flow_control.cpp</div> </div> |
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| <div class="contents"> |
| <p>A multithreaded sender and receiver enhanced for flow control.<b>Requires C++11</b></p> |
| <div class="fragment"><div class="line"><span class="comment">/*</span></div> |
| <div class="line"><span class="comment"> * Licensed to the Apache Software Foundation (ASF) under one</span></div> |
| <div class="line"><span class="comment"> * or more contributor license agreements. See the NOTICE file</span></div> |
| <div class="line"><span class="comment"> * distributed with this work for additional information</span></div> |
| <div class="line"><span class="comment"> * regarding copyright ownership. The ASF licenses this file</span></div> |
| <div class="line"><span class="comment"> * to you under the Apache License, Version 2.0 (the</span></div> |
| <div class="line"><span class="comment"> * "License"); you may not use this file except in compliance</span></div> |
| <div class="line"><span class="comment"> * with the License. You may obtain a copy of the License at</span></div> |
| <div class="line"><span class="comment"> *</span></div> |
| <div class="line"><span class="comment"> * http://www.apache.org/licenses/LICENSE-2.0</span></div> |
| <div class="line"><span class="comment"> *</span></div> |
| <div class="line"><span class="comment"> * Unless required by applicable law or agreed to in writing,</span></div> |
| <div class="line"><span class="comment"> * software distributed under the License is distributed on an</span></div> |
| <div class="line"><span class="comment"> * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY</span></div> |
| <div class="line"><span class="comment"> * KIND, either express or implied. See the License for the</span></div> |
| <div class="line"><span class="comment"> * specific language governing permissions and limitations</span></div> |
| <div class="line"><span class="comment"> * under the License.</span></div> |
| <div class="line"><span class="comment"> */</span></div> |
| <div class="line"> </div> |
| <div class="line"><span class="comment">//</span></div> |
| <div class="line"><span class="comment">// C++11 or greater</span></div> |
| <div class="line"><span class="comment">//</span></div> |
| <div class="line"><span class="comment">// A multi-threaded client that sends and receives messages from multiple AMQP</span></div> |
| <div class="line"><span class="comment">// addresses.</span></div> |
| <div class="line"><span class="comment">//</span></div> |
| <div class="line"><span class="comment">// Demonstrates how to:</span></div> |
| <div class="line"><span class="comment">//</span></div> |
| <div class="line"><span class="comment">// - implement proton handlers that interact with user threads safely</span></div> |
| <div class="line"><span class="comment">// - block sender threads to respect AMQP flow control</span></div> |
| <div class="line"><span class="comment">// - use AMQP flow control to limit message buffering for receivers threads</span></div> |
| <div class="line"><span class="comment">//</span></div> |
| <div class="line"><span class="comment">// We define sender and receiver classes with simple, thread-safe blocking</span></div> |
| <div class="line"><span class="comment">// send() and receive() functions.</span></div> |
| <div class="line"><span class="comment">//</span></div> |
| <div class="line"><span class="comment">// These classes are also privately proton::message_handler instances. They use</span></div> |
| <div class="line"><span class="comment">// the thread-safe proton::work_queue and standard C++ synchronization (std::mutex</span></div> |
| <div class="line"><span class="comment">// etc.) to pass messages between user and proton::container threads.</span></div> |
| <div class="line"><span class="comment">//</span></div> |
| <div class="line"><span class="comment">// NOTE: no proper error handling</span></div> |
| <div class="line"> </div> |
| <div class="line"><span class="preprocessor">#include <<a class="code" href="connection_8hpp.html">proton/connection.hpp</a>></span></div> |
| <div class="line"><span class="preprocessor">#include <<a class="code" href="connection__options_8hpp.html">proton/connection_options.hpp</a>></span></div> |
| <div class="line"><span class="preprocessor">#include <<a class="code" href="container_8hpp.html">proton/container.hpp</a>></span></div> |
| <div class="line"><span class="preprocessor">#include <<a class="code" href="message_8hpp.html">proton/message.hpp</a>></span></div> |
| <div class="line"><span class="preprocessor">#include <<a class="code" href="messaging__handler_8hpp.html">proton/messaging_handler.hpp</a>></span></div> |
| <div class="line"><span class="preprocessor">#include <<a class="code" href="receiver_8hpp.html">proton/receiver.hpp</a>></span></div> |
| <div class="line"><span class="preprocessor">#include <<a class="code" href="receiver__options_8hpp.html">proton/receiver_options.hpp</a>></span></div> |
| <div class="line"><span class="preprocessor">#include <<a class="code" href="sender_8hpp.html">proton/sender.hpp</a>></span></div> |
| <div class="line"><span class="preprocessor">#include <<a class="code" href="work__queue_8hpp.html">proton/work_queue.hpp</a>></span></div> |
| <div class="line"> </div> |
| <div class="line"><span class="preprocessor">#include <atomic></span></div> |
| <div class="line"><span class="preprocessor">#include <condition_variable></span></div> |
| <div class="line"><span class="preprocessor">#include <iostream></span></div> |
| <div class="line"><span class="preprocessor">#include <mutex></span></div> |
| <div class="line"><span class="preprocessor">#include <queue></span></div> |
| <div class="line"><span class="preprocessor">#include <sstream></span></div> |
| <div class="line"><span class="preprocessor">#include <string></span></div> |
| <div class="line"><span class="preprocessor">#include <thread></span></div> |
| <div class="line"> </div> |
| <div class="line"><span class="comment">// Lock output from threads to avoid scrambling</span></div> |
| <div class="line">std::mutex out_lock;</div> |
| <div class="line"><span class="preprocessor">#define OUT(x) do { std::lock_guard<std::mutex> l(out_lock); x; } while (false)</span></div> |
| <div class="line"> </div> |
| <div class="line"><span class="comment">// Exception raised if a sender or receiver is closed when trying to send/receive</span></div> |
| <div class="line"><span class="keyword">class </span>closed : <span class="keyword">public</span> std::runtime_error {</div> |
| <div class="line"> <span class="keyword">public</span>:</div> |
| <div class="line"> closed(<span class="keyword">const</span> std::string& msg) : std::runtime_error(msg) {}</div> |
| <div class="line">};</div> |
| <div class="line"> </div> |
| <div class="line"><span class="comment">// A thread-safe sending connection that blocks sending threads when there</span></div> |
| <div class="line"><span class="comment">// is no AMQP credit to send messages.</span></div> |
| <div class="line"><span class="keyword">class </span>sender : <span class="keyword">private</span> <a name="_a0"></a><a class="code" href="classproton_1_1messaging__handler.html">proton::messaging_handler</a> {</div> |
| <div class="line"> <span class="comment">// Only used in proton handler thread</span></div> |
| <div class="line"> <a name="_a1"></a><a class="code" href="classproton_1_1sender.html">proton::sender</a> sender_;</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Shared by proton and user threads, protected by lock_</span></div> |
| <div class="line"> std::mutex lock_;</div> |
| <div class="line"> <a name="_a2"></a><a class="code" href="classproton_1_1work__queue.html">proton::work_queue</a> *work_queue_;</div> |
| <div class="line"> std::condition_variable sender_ready_;</div> |
| <div class="line"> <span class="keywordtype">int</span> queued_; <span class="comment">// Queued messages waiting to be sent</span></div> |
| <div class="line"> <span class="keywordtype">int</span> credit_; <span class="comment">// AMQP credit - number of messages we can send</span></div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keyword">public</span>:</div> |
| <div class="line"> sender(<a name="_a3"></a><a class="code" href="classproton_1_1container.html">proton::container</a>& cont, <span class="keyword">const</span> std::string& url, <span class="keyword">const</span> std::string& address)</div> |
| <div class="line"> : work_queue_(0), queued_(0), credit_(0)</div> |
| <div class="line"> {</div> |
| <div class="line"> cont.<a name="a4"></a><a class="code" href="classproton_1_1container.html#adfbfd13668611a525bb44328d7a3b1e8">open_sender</a>(url+<span class="stringliteral">"/"</span>+address, <a name="_a5"></a><a class="code" href="classproton_1_1connection__options.html">proton::connection_options</a>().handler(*<span class="keyword">this</span>));</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Thread safe</span></div> |
| <div class="line"> <span class="keywordtype">void</span> send(<span class="keyword">const</span> <a name="_a6"></a><a class="code" href="classproton_1_1message.html">proton::message</a>& m) {</div> |
| <div class="line"> {</div> |
| <div class="line"> std::unique_lock<std::mutex> l(lock_);</div> |
| <div class="line"> <span class="comment">// Don't queue up more messages than we have credit for</span></div> |
| <div class="line"> <span class="keywordflow">while</span> (!work_queue_ || queued_ >= credit_) sender_ready_.wait(l);</div> |
| <div class="line"> ++queued_;</div> |
| <div class="line"> }</div> |
| <div class="line"> work_queue_-><a name="a7"></a><a class="code" href="classproton_1_1work__queue.html#a59dae2153455bc095477a3b66a0b681e">add</a>([=]() { this->do_send(m); }); <span class="comment">// work_queue_ is thread safe</span></div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Thread safe</span></div> |
| <div class="line"> <span class="keywordtype">void</span> close() {</div> |
| <div class="line"> work_queue()->add([=]() { sender_.<a name="a8"></a><a class="code" href="classproton_1_1link.html#aff302bb6016f2ae29f01bb4e07389a52">connection</a>().close(); });</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keyword">private</span>:</div> |
| <div class="line"> </div> |
| <div class="line"> <a class="code" href="classproton_1_1work__queue.html">proton::work_queue</a>* work_queue() {</div> |
| <div class="line"> <span class="comment">// Wait till work_queue_ and sender_ are initialized.</span></div> |
| <div class="line"> std::unique_lock<std::mutex> l(lock_);</div> |
| <div class="line"> <span class="keywordflow">while</span> (!work_queue_) sender_ready_.wait(l);</div> |
| <div class="line"> <span class="keywordflow">return</span> work_queue_;</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// == messaging_handler overrides, only called in proton handler thread</span></div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keywordtype">void</span> <a name="a9"></a><a class="code" href="classproton_1_1messaging__handler.html#ac655d56c64574c9eb7b10e80d32764f4">on_sender_open</a>(<a class="code" href="classproton_1_1sender.html">proton::sender</a>& s)<span class="keyword"> override </span>{</div> |
| <div class="line"> <span class="comment">// Make sure sender_ and work_queue_ are set atomically</span></div> |
| <div class="line"> std::lock_guard<std::mutex> l(lock_);</div> |
| <div class="line"> sender_ = s;</div> |
| <div class="line"> work_queue_ = &s.<a name="a10"></a><a class="code" href="classproton_1_1link.html#a7c755d6ac6385e007adb61966598ba63">work_queue</a>();</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keywordtype">void</span> <a name="a11"></a><a class="code" href="classproton_1_1messaging__handler.html#a86c9509ba3ce1925150c5b7a9a937c94">on_sendable</a>(<a class="code" href="classproton_1_1sender.html">proton::sender</a>& s)<span class="keyword"> override </span>{</div> |
| <div class="line"> std::lock_guard<std::mutex> l(lock_);</div> |
| <div class="line"> credit_ = s.<a name="a12"></a><a class="code" href="classproton_1_1link.html#afd27bd11ba72d7df51c44f71b15749eb">credit</a>();</div> |
| <div class="line"> sender_ready_.notify_all(); <span class="comment">// Notify senders we have credit</span></div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// work_queue work items is are automatically dequeued and called by proton</span></div> |
| <div class="line"> <span class="comment">// This function is called because it was queued by send()</span></div> |
| <div class="line"> <span class="keywordtype">void</span> do_send(<span class="keyword">const</span> <a class="code" href="classproton_1_1message.html">proton::message</a>& m) {</div> |
| <div class="line"> sender_.<a name="a13"></a><a class="code" href="classproton_1_1sender.html#a214eb30b24e6831d016a47b9dddda830">send</a>(m);</div> |
| <div class="line"> std::lock_guard<std::mutex> l(lock_);</div> |
| <div class="line"> --queued_; <span class="comment">// work item was consumed from the work_queue</span></div> |
| <div class="line"> credit_ = sender_.<a class="code" href="classproton_1_1link.html#afd27bd11ba72d7df51c44f71b15749eb">credit</a>(); <span class="comment">// update credit</span></div> |
| <div class="line"> sender_ready_.notify_all(); <span class="comment">// Notify senders we have space on queue</span></div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keywordtype">void</span> <a name="a14"></a><a class="code" href="classproton_1_1messaging__handler.html#a042f595d1807eb1abe0195ab79357edd">on_error</a>(<span class="keyword">const</span> <a name="_a15"></a><a class="code" href="classproton_1_1error__condition.html">proton::error_condition</a>& e)<span class="keyword"> override </span>{</div> |
| <div class="line"> OUT(std::cerr << <span class="stringliteral">"unexpected error: "</span> << e << std::endl);</div> |
| <div class="line"> exit(1);</div> |
| <div class="line"> }</div> |
| <div class="line">};</div> |
| <div class="line"> </div> |
| <div class="line"><span class="comment">// A thread safe receiving connection that blocks receiving threads when there</span></div> |
| <div class="line"><span class="comment">// are no messages available, and maintains a bounded buffer of incoming</span></div> |
| <div class="line"><span class="comment">// messages by issuing AMQP credit only when there is space in the buffer.</span></div> |
| <div class="line"><span class="keyword">class </span>receiver : <span class="keyword">private</span> <a class="code" href="classproton_1_1messaging__handler.html">proton::messaging_handler</a> {</div> |
| <div class="line"> <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">size_t</span> MAX_BUFFER = 100; <span class="comment">// Max number of buffered messages</span></div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Used in proton threads only</span></div> |
| <div class="line"> <a name="_a16"></a><a class="code" href="classproton_1_1receiver.html">proton::receiver</a> receiver_;</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Used in proton and user threads, protected by lock_</span></div> |
| <div class="line"> std::mutex lock_;</div> |
| <div class="line"> <a class="code" href="classproton_1_1work__queue.html">proton::work_queue</a>* work_queue_;</div> |
| <div class="line"> std::queue<proton::message> buffer_; <span class="comment">// Messages not yet returned by receive()</span></div> |
| <div class="line"> std::condition_variable can_receive_; <span class="comment">// Notify receivers of messages</span></div> |
| <div class="line"> <span class="keywordtype">bool</span> closed_;</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keyword">public</span>:</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Connect to url</span></div> |
| <div class="line"> receiver(<a class="code" href="classproton_1_1container.html">proton::container</a>& cont, <span class="keyword">const</span> std::string& url, <span class="keyword">const</span> std::string& address)</div> |
| <div class="line"> : work_queue_(0), closed_(false)</div> |
| <div class="line"> {</div> |
| <div class="line"> <span class="comment">// NOTE:credit_window(0) disables automatic flow control.</span></div> |
| <div class="line"> <span class="comment">// We will use flow control to match AMQP credit to buffer capacity.</span></div> |
| <div class="line"> cont.<a name="a17"></a><a class="code" href="classproton_1_1container.html#a15df75d582af4ed83f0ffab9dcce84bf">open_receiver</a>(url+<span class="stringliteral">"/"</span>+address, <a name="_a18"></a><a class="code" href="classproton_1_1receiver__options.html">proton::receiver_options</a>().credit_window(0),</div> |
| <div class="line"> <a class="code" href="classproton_1_1connection__options.html">proton::connection_options</a>().handler(*<span class="keyword">this</span>));</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Thread safe receive</span></div> |
| <div class="line"> <a class="code" href="classproton_1_1message.html">proton::message</a> receive() {</div> |
| <div class="line"> std::unique_lock<std::mutex> l(lock_);</div> |
| <div class="line"> <span class="comment">// Wait for buffered messages</span></div> |
| <div class="line"> <span class="keywordflow">while</span> (!closed_ && (!work_queue_ || buffer_.empty())) {</div> |
| <div class="line"> can_receive_.wait(l);</div> |
| <div class="line"> }</div> |
| <div class="line"> <span class="keywordflow">if</span> (closed_) <span class="keywordflow">throw</span> closed(<span class="stringliteral">"receiver closed"</span>);</div> |
| <div class="line"> <a class="code" href="classproton_1_1message.html">proton::message</a> m = std::move(buffer_.front());</div> |
| <div class="line"> buffer_.pop();</div> |
| <div class="line"> <span class="comment">// Add a lambda to the work queue to call receive_done().</span></div> |
| <div class="line"> <span class="comment">// This will tell the handler to add more credit.</span></div> |
| <div class="line"> work_queue_-><a class="code" href="classproton_1_1work__queue.html#a59dae2153455bc095477a3b66a0b681e">add</a>([=]() { this->receive_done(); });</div> |
| <div class="line"> <span class="keywordflow">return</span> m;</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Thread safe</span></div> |
| <div class="line"> <span class="keywordtype">void</span> close() {</div> |
| <div class="line"> std::lock_guard<std::mutex> l(lock_);</div> |
| <div class="line"> <span class="keywordflow">if</span> (!closed_) {</div> |
| <div class="line"> closed_ = <span class="keyword">true</span>;</div> |
| <div class="line"> can_receive_.notify_all();</div> |
| <div class="line"> <span class="keywordflow">if</span> (work_queue_) {</div> |
| <div class="line"> work_queue_-><a class="code" href="classproton_1_1work__queue.html#a59dae2153455bc095477a3b66a0b681e">add</a>([<span class="keyword">this</span>]() { this->receiver_.<a class="code" href="classproton_1_1link.html#aff302bb6016f2ae29f01bb4e07389a52">connection</a>().close(); });</div> |
| <div class="line"> }</div> |
| <div class="line"> }</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keyword">private</span>:</div> |
| <div class="line"> <span class="comment">// ==== The following are called by proton threads only.</span></div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keywordtype">void</span> <a name="a19"></a><a class="code" href="classproton_1_1messaging__handler.html#a77f7e38659ee43ccb764e417ad6dd401">on_receiver_open</a>(<a class="code" href="classproton_1_1receiver.html">proton::receiver</a>& r)<span class="keyword"> override </span>{</div> |
| <div class="line"> receiver_ = r;</div> |
| <div class="line"> std::lock_guard<std::mutex> l(lock_);</div> |
| <div class="line"> work_queue_ = &receiver_.<a class="code" href="classproton_1_1link.html#a7c755d6ac6385e007adb61966598ba63">work_queue</a>();</div> |
| <div class="line"> receiver_.<a name="a20"></a><a class="code" href="classproton_1_1receiver.html#a84d3a001340d11201e03c6ed7c763641">add_credit</a>(MAX_BUFFER); <span class="comment">// Buffer is empty, initial credit is the limit</span></div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keywordtype">void</span> <a name="a21"></a><a class="code" href="classproton_1_1messaging__handler.html#a584c9daeadf4322801f58e054017fecb">on_message</a>(<a name="_a22"></a><a class="code" href="classproton_1_1delivery.html">proton::delivery</a> &d, <a class="code" href="classproton_1_1message.html">proton::message</a> &m)<span class="keyword"> override </span>{</div> |
| <div class="line"> <span class="comment">// Proton automatically reduces credit by 1 before calling on_message</span></div> |
| <div class="line"> std::lock_guard<std::mutex> l(lock_);</div> |
| <div class="line"> buffer_.push(m);</div> |
| <div class="line"> can_receive_.notify_all();</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// called via work_queue</span></div> |
| <div class="line"> <span class="keywordtype">void</span> receive_done() {</div> |
| <div class="line"> <span class="comment">// Add 1 credit, a receiver has taken a message out of the buffer.</span></div> |
| <div class="line"> receiver_.<a class="code" href="classproton_1_1receiver.html#a84d3a001340d11201e03c6ed7c763641">add_credit</a>(1);</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keywordtype">void</span> <a class="code" href="classproton_1_1messaging__handler.html#a042f595d1807eb1abe0195ab79357edd">on_error</a>(<span class="keyword">const</span> <a class="code" href="classproton_1_1error__condition.html">proton::error_condition</a>& e)<span class="keyword"> override </span>{</div> |
| <div class="line"> OUT(std::cerr << <span class="stringliteral">"unexpected error: "</span> << e << std::endl);</div> |
| <div class="line"> exit(1);</div> |
| <div class="line"> }</div> |
| <div class="line">};</div> |
| <div class="line"> </div> |
| <div class="line"><span class="comment">// ==== Example code using the sender and receiver</span></div> |
| <div class="line"> </div> |
| <div class="line"><span class="comment">// Send n messages</span></div> |
| <div class="line"><span class="keywordtype">void</span> send_thread(sender& s, <span class="keywordtype">int</span> n) {</div> |
| <div class="line"> <span class="keyword">auto</span> <span class="keywordtype">id</span> = std::this_thread::get_id();</div> |
| <div class="line"> <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i < n; ++i) {</div> |
| <div class="line"> std::ostringstream ss;</div> |
| <div class="line"> ss << std::this_thread::get_id() << <span class="stringliteral">"-"</span> << i;</div> |
| <div class="line"> s.send(<a class="code" href="classproton_1_1message.html">proton::message</a>(ss.str()));</div> |
| <div class="line"> OUT(std::cout << <span class="keywordtype">id</span> << <span class="stringliteral">" sent \""</span> << ss.str() << <span class="charliteral">'"'</span> << std::endl);</div> |
| <div class="line"> }</div> |
| <div class="line"> OUT(std::cout << <span class="keywordtype">id</span> << <span class="stringliteral">" sent "</span> << n << std::endl);</div> |
| <div class="line">}</div> |
| <div class="line"> </div> |
| <div class="line"><span class="comment">// Receive messages till atomic remaining count is 0.</span></div> |
| <div class="line"><span class="comment">// remaining is shared among all receiving threads</span></div> |
| <div class="line"><span class="keywordtype">void</span> receive_thread(receiver& r, std::atomic_int& remaining) {</div> |
| <div class="line"> <span class="keywordflow">try</span> {</div> |
| <div class="line"> <span class="keyword">auto</span> <span class="keywordtype">id</span> = std::this_thread::get_id();</div> |
| <div class="line"> <span class="keywordtype">int</span> n = 0;</div> |
| <div class="line"> <span class="comment">// atomically check and decrement remaining *before* receiving.</span></div> |
| <div class="line"> <span class="comment">// If it is 0 or less then return, as there are no more</span></div> |
| <div class="line"> <span class="comment">// messages to receive so calling r.receive() would block forever.</span></div> |
| <div class="line"> <span class="keywordflow">while</span> (remaining-- > 0) {</div> |
| <div class="line"> <span class="keyword">auto</span> m = r.receive();</div> |
| <div class="line"> ++n;</div> |
| <div class="line"> OUT(std::cout << <span class="keywordtype">id</span> << <span class="stringliteral">" received \""</span> << m.<a name="a23"></a><a class="code" href="classproton_1_1message.html#ae9af642f154a68ec0eb8e715ecaf95ae">body</a>() << <span class="charliteral">'"'</span> << std::endl);</div> |
| <div class="line"> }</div> |
| <div class="line"> OUT(std::cout << <span class="keywordtype">id</span> << <span class="stringliteral">" received "</span> << n << <span class="stringliteral">" messages"</span> << std::endl);</div> |
| <div class="line"> } <span class="keywordflow">catch</span> (<span class="keyword">const</span> closed&) {}</div> |
| <div class="line">}</div> |
| <div class="line"> </div> |
| <div class="line"><span class="keywordtype">int</span> main(<span class="keywordtype">int</span> argc, <span class="keyword">const</span> <span class="keywordtype">char</span> **argv) {</div> |
| <div class="line"> <span class="keywordflow">try</span> {</div> |
| <div class="line"> <span class="keywordflow">if</span> (argc != 5) {</div> |
| <div class="line"> std::cerr <<</div> |
| <div class="line"> <span class="stringliteral">"Usage: "</span> << argv[0] << <span class="stringliteral">" CONNECTION-URL AMQP-ADDRESS MESSAGE-COUNT THREAD-COUNT\n"</span></div> |
| <div class="line"> <span class="stringliteral">"CONNECTION-URL: connection address, e.g.'amqp://127.0.0.1'\n"</span></div> |
| <div class="line"> <span class="stringliteral">"AMQP-ADDRESS: AMQP node address, e.g. 'examples'\n"</span></div> |
| <div class="line"> <span class="stringliteral">"MESSAGE-COUNT: number of messages to send\n"</span></div> |
| <div class="line"> <span class="stringliteral">"THREAD-COUNT: number of sender/receiver thread pairs\n"</span>;</div> |
| <div class="line"> <span class="keywordflow">return</span> 1;</div> |
| <div class="line"> }</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keyword">const</span> <span class="keywordtype">char</span> *url = argv[1];</div> |
| <div class="line"> <span class="keyword">const</span> <span class="keywordtype">char</span> *address = argv[2];</div> |
| <div class="line"> <span class="keywordtype">int</span> n_messages = atoi(argv[3]);</div> |
| <div class="line"> <span class="keywordtype">int</span> n_threads = atoi(argv[4]);</div> |
| <div class="line"> <span class="keywordtype">int</span> count = n_messages * n_threads;</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Total messages to be received, multiple receiver threads will decrement this.</span></div> |
| <div class="line"> std::atomic_int remaining;</div> |
| <div class="line"> remaining.store(count);</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Run the proton container</span></div> |
| <div class="line"> <a class="code" href="classproton_1_1container.html">proton::container</a> container;</div> |
| <div class="line"> <span class="keyword">auto</span> container_thread = std::thread([&]() { container.<a name="a24"></a><a class="code" href="classproton_1_1container.html#a13a43e6d814de94978c515cb084873b1">run</a>(); });</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// A single sender and receiver to be shared by all the threads</span></div> |
| <div class="line"> sender send(container, url, address);</div> |
| <div class="line"> receiver recv(container, url, address);</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Start receiver threads, then sender threads.</span></div> |
| <div class="line"> <span class="comment">// Starting receivers first gives all receivers a chance to compete for messages.</span></div> |
| <div class="line"> std::vector<std::thread> threads;</div> |
| <div class="line"> threads.reserve(n_threads*2); <span class="comment">// Avoid re-allocation once threads are started</span></div> |
| <div class="line"> <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i < n_threads; ++i)</div> |
| <div class="line"> threads.push_back(std::thread([&]() { receive_thread(recv, remaining); }));</div> |
| <div class="line"> <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i < n_threads; ++i)</div> |
| <div class="line"> threads.push_back(std::thread([&]() { send_thread(send, n_messages); }));</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="comment">// Wait for threads to finish</span></div> |
| <div class="line"> <span class="keywordflow">for</span> (<span class="keyword">auto</span>& t : threads) t.join();</div> |
| <div class="line"> send.close();</div> |
| <div class="line"> recv.close();</div> |
| <div class="line"> container_thread.join();</div> |
| <div class="line"> <span class="keywordflow">if</span> (remaining > 0)</div> |
| <div class="line"> <span class="keywordflow">throw</span> std::runtime_error(<span class="stringliteral">"not all messages were received"</span>);</div> |
| <div class="line"> std::cout << count << <span class="stringliteral">" messages sent and received"</span> << std::endl;</div> |
| <div class="line"> </div> |
| <div class="line"> <span class="keywordflow">return</span> 0;</div> |
| <div class="line"> } <span class="keywordflow">catch</span> (<span class="keyword">const</span> std::exception& e) {</div> |
| <div class="line"> std::cerr << e.what() << std::endl;</div> |
| <div class="line"> }</div> |
| <div class="line"> <span class="keywordflow">return</span> 1;</div> |
| <div class="line">}</div> |
| </div><!-- fragment --> </div><!-- contents --> |
| </div><!-- doc-content --> |
| <div class="ttc" id="aclassproton_1_1error__condition_html"><div class="ttname"><a href="classproton_1_1error__condition.html">proton::error_condition</a></div><div class="ttdoc">Describes an endpoint error state.</div><div class="ttdef"><b>Definition:</b> error_condition.hpp:40</div></div> |
| <div class="ttc" id="amessaging__handler_8hpp_html"><div class="ttname"><a href="messaging__handler_8hpp.html">messaging_handler.hpp</a></div><div class="ttdoc">Handler for Proton messaging events.</div></div> |
| <div class="ttc" id="amessage_8hpp_html"><div class="ttname"><a href="message_8hpp.html">message.hpp</a></div><div class="ttdoc">An AMQP message.</div></div> |
| <div class="ttc" id="aclassproton_1_1receiver_html_a84d3a001340d11201e03c6ed7c763641"><div class="ttname"><a href="classproton_1_1receiver.html#a84d3a001340d11201e03c6ed7c763641">proton::receiver::add_credit</a></div><div class="ttdeci">void add_credit(uint32_t)</div><div class="ttdoc">Increment the credit available to the sender.</div></div> |
| <div class="ttc" id="aclassproton_1_1container_html"><div class="ttname"><a href="classproton_1_1container.html">proton::container</a></div><div class="ttdoc">A top-level container of connections, sessions, and links.</div><div class="ttdef"><b>Definition:</b> container.hpp:50</div></div> |
| <div class="ttc" id="aclassproton_1_1link_html_aff302bb6016f2ae29f01bb4e07389a52"><div class="ttname"><a href="classproton_1_1link.html#aff302bb6016f2ae29f01bb4e07389a52">proton::link::connection</a></div><div class="ttdeci">class connection connection() const</div><div class="ttdoc">The connection that owns this link.</div></div> |
| <div class="ttc" id="awork__queue_8hpp_html"><div class="ttname"><a href="work__queue_8hpp.html">work_queue.hpp</a></div><div class="ttdoc">Unsettled API - A context for thread-safe execution of work.</div></div> |
| <div class="ttc" id="aclassproton_1_1messaging__handler_html_a042f595d1807eb1abe0195ab79357edd"><div class="ttname"><a href="classproton_1_1messaging__handler.html#a042f595d1807eb1abe0195ab79357edd">proton::messaging_handler::on_error</a></div><div class="ttdeci">virtual void on_error(const error_condition &)</div><div class="ttdoc">Fallback error handling.</div></div> |
| <div class="ttc" id="areceiver__options_8hpp_html"><div class="ttname"><a href="receiver__options_8hpp.html">receiver_options.hpp</a></div><div class="ttdoc">Options for creating a receiver.</div></div> |
| <div class="ttc" id="aclassproton_1_1receiver__options_html"><div class="ttname"><a href="classproton_1_1receiver__options.html">proton::receiver_options</a></div><div class="ttdoc">Options for creating a receiver.</div><div class="ttdef"><b>Definition:</b> receiver_options.hpp:56</div></div> |
| <div class="ttc" id="aclassproton_1_1messaging__handler_html_a584c9daeadf4322801f58e054017fecb"><div class="ttname"><a href="classproton_1_1messaging__handler.html#a584c9daeadf4322801f58e054017fecb">proton::messaging_handler::on_message</a></div><div class="ttdeci">virtual void on_message(delivery &, message &)</div><div class="ttdoc">A message is received.</div></div> |
| <div class="ttc" id="aclassproton_1_1receiver_html"><div class="ttname"><a href="classproton_1_1receiver.html">proton::receiver</a></div><div class="ttdoc">A channel for receiving messages.</div><div class="ttdef"><b>Definition:</b> receiver.hpp:41</div></div> |
| <div class="ttc" id="aclassproton_1_1connection__options_html"><div class="ttname"><a href="classproton_1_1connection__options.html">proton::connection_options</a></div><div class="ttdoc">Options for creating a connection.</div><div class="ttdef"><b>Definition:</b> connection_options.hpp:67</div></div> |
| <div class="ttc" id="aclassproton_1_1delivery_html"><div class="ttname"><a href="classproton_1_1delivery.html">proton::delivery</a></div><div class="ttdoc">A received message.</div><div class="ttdef"><b>Definition:</b> delivery.hpp:39</div></div> |
| <div class="ttc" id="aclassproton_1_1messaging__handler_html_a86c9509ba3ce1925150c5b7a9a937c94"><div class="ttname"><a href="classproton_1_1messaging__handler.html#a86c9509ba3ce1925150c5b7a9a937c94">proton::messaging_handler::on_sendable</a></div><div class="ttdeci">virtual void on_sendable(sender &)</div><div class="ttdoc">A message can be sent.</div></div> |
| <div class="ttc" id="aconnection_8hpp_html"><div class="ttname"><a href="connection_8hpp.html">connection.hpp</a></div><div class="ttdoc">A connection to a remote AMQP peer.</div></div> |
| <div class="ttc" id="aclassproton_1_1work__queue_html_a59dae2153455bc095477a3b66a0b681e"><div class="ttname"><a href="classproton_1_1work__queue.html#a59dae2153455bc095477a3b66a0b681e">proton::work_queue::add</a></div><div class="ttdeci">bool add(work fn)</div><div class="ttdoc">Unsettled API - Add work fn to the work queue.</div></div> |
| <div class="ttc" id="areceiver_8hpp_html"><div class="ttname"><a href="receiver_8hpp.html">receiver.hpp</a></div><div class="ttdoc">A channel for receiving messages.</div></div> |
| <div class="ttc" id="asender_8hpp_html"><div class="ttname"><a href="sender_8hpp.html">sender.hpp</a></div><div class="ttdoc">A channel for sending messages.</div></div> |
| <div class="ttc" id="aclassproton_1_1sender_html_a214eb30b24e6831d016a47b9dddda830"><div class="ttname"><a href="classproton_1_1sender.html#a214eb30b24e6831d016a47b9dddda830">proton::sender::send</a></div><div class="ttdeci">tracker send(const message &m)</div><div class="ttdoc">Send a message on the sender.</div></div> |
| <div class="ttc" id="aclassproton_1_1messaging__handler_html"><div class="ttname"><a href="classproton_1_1messaging__handler.html">proton::messaging_handler</a></div><div class="ttdoc">Handler for Proton messaging events.</div><div class="ttdef"><b>Definition:</b> messaging_handler.hpp:69</div></div> |
| <div class="ttc" id="aconnection__options_8hpp_html"><div class="ttname"><a href="connection__options_8hpp.html">connection_options.hpp</a></div><div class="ttdoc">Options for creating a connection.</div></div> |
| <div class="ttc" id="aclassproton_1_1sender_html"><div class="ttname"><a href="classproton_1_1sender.html">proton::sender</a></div><div class="ttdoc">A channel for sending messages.</div><div class="ttdef"><b>Definition:</b> sender.hpp:40</div></div> |
| <div class="ttc" id="aclassproton_1_1link_html_afd27bd11ba72d7df51c44f71b15749eb"><div class="ttname"><a href="classproton_1_1link.html#afd27bd11ba72d7df51c44f71b15749eb">proton::link::credit</a></div><div class="ttdeci">int credit() const</div><div class="ttdoc">Credit available on the link.</div></div> |
| <div class="ttc" id="aclassproton_1_1messaging__handler_html_a77f7e38659ee43ccb764e417ad6dd401"><div class="ttname"><a href="classproton_1_1messaging__handler.html#a77f7e38659ee43ccb764e417ad6dd401">proton::messaging_handler::on_receiver_open</a></div><div class="ttdeci">virtual void on_receiver_open(receiver &)</div><div class="ttdoc">The remote peer opened the link.</div></div> |
| <div class="ttc" id="aclassproton_1_1link_html_a7c755d6ac6385e007adb61966598ba63"><div class="ttname"><a href="classproton_1_1link.html#a7c755d6ac6385e007adb61966598ba63">proton::link::work_queue</a></div><div class="ttdeci">class work_queue & work_queue() const</div><div class="ttdoc">Get the work_queue for the link.</div></div> |
| <div class="ttc" id="aclassproton_1_1message_html_ae9af642f154a68ec0eb8e715ecaf95ae"><div class="ttname"><a href="classproton_1_1message.html#ae9af642f154a68ec0eb8e715ecaf95ae">proton::message::body</a></div><div class="ttdeci">void body(const value &x)</div><div class="ttdoc">Set the body. Equivalent to body() = x.</div></div> |
| <div class="ttc" id="aclassproton_1_1messaging__handler_html_ac655d56c64574c9eb7b10e80d32764f4"><div class="ttname"><a href="classproton_1_1messaging__handler.html#ac655d56c64574c9eb7b10e80d32764f4">proton::messaging_handler::on_sender_open</a></div><div class="ttdeci">virtual void on_sender_open(sender &)</div><div class="ttdoc">The remote peer opened the link.</div></div> |
| <div class="ttc" id="aclassproton_1_1container_html_a13a43e6d814de94978c515cb084873b1"><div class="ttname"><a href="classproton_1_1container.html#a13a43e6d814de94978c515cb084873b1">proton::container::run</a></div><div class="ttdeci">void run()</div><div class="ttdoc">Run the container in the current thread.</div></div> |
| <div class="ttc" id="acontainer_8hpp_html"><div class="ttname"><a href="container_8hpp.html">container.hpp</a></div><div class="ttdoc">A top-level container of connections, sessions, and links.</div></div> |
| <div class="ttc" id="aclassproton_1_1container_html_a15df75d582af4ed83f0ffab9dcce84bf"><div class="ttname"><a href="classproton_1_1container.html#a15df75d582af4ed83f0ffab9dcce84bf">proton::container::open_receiver</a></div><div class="ttdeci">returned< receiver > open_receiver(const std::string &addr_url)</div><div class="ttdoc">Open a connection and receiver for addr_url.</div></div> |
| <div class="ttc" id="aclassproton_1_1container_html_adfbfd13668611a525bb44328d7a3b1e8"><div class="ttname"><a href="classproton_1_1container.html#adfbfd13668611a525bb44328d7a3b1e8">proton::container::open_sender</a></div><div class="ttdeci">returned< sender > open_sender(const std::string &addr_url)</div><div class="ttdoc">Open a connection and sender for addr_url.</div></div> |
| <div class="ttc" id="aclassproton_1_1message_html"><div class="ttname"><a href="classproton_1_1message.html">proton::message</a></div><div class="ttdoc">An AMQP message.</div><div class="ttdef"><b>Definition:</b> message.hpp:50</div></div> |
| <div class="ttc" id="aclassproton_1_1work__queue_html"><div class="ttname"><a href="classproton_1_1work__queue.html">proton::work_queue</a></div><div class="ttdoc">Unsettled API - A context for thread-safe execution of work.</div><div class="ttdef"><b>Definition:</b> work_queue.hpp:339</div></div> |
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