update source to Ceph Pacific 16.2.2

[ceph.git] / ceph / src / seastar / demos / tutorial_examples.cc

diff --git a/ceph/src/seastar/demos/tutorial_examples.cc b/ceph/src/seastar/demos/tutorial_examples.cc
new file mode 100644 (file)
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+++ b/ceph/src/seastar/demos/tutorial_examples.cc
@@ -0,0 +1,117 @@
+/*
+ * This file is open source software, licensed to you under the terms
+ * of the Apache License, Version 2.0 (the "License").  See the NOTICE file
+ * distributed with this work for additional information regarding copyright
+ * ownership.  You may not use this file except in compliance with the License.
+ *
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+/*
+ * Copyright (C) 2020 ScyllaDB.
+ */
+
+#include <iostream>
+
+#include <seastar/core/seastar.hh>
+#include <seastar/core/reactor.hh>
+#include <seastar/core/future-util.hh>
+#include <seastar/net/api.hh>
+
+seastar::future<> service_loop() {
+    return seastar::do_with(seastar::listen(seastar::make_ipv4_address({1234})),
+            [] (auto& listener) {
+        return seastar::keep_doing([&listener] () {
+            return listener.accept().then(
+                [] (seastar::accept_result res) {
+                    std::cout << "Accepted connection from " << res.remote_address << "\n";
+            });
+        });
+    });
+}
+
+const char* canned_response = "Seastar is the future!\n";
+
+seastar::future<> service_loop_2() {
+    seastar::listen_options lo;
+    lo.reuse_address = true;
+    return seastar::do_with(seastar::listen(seastar::make_ipv4_address({1234}), lo),
+            [] (auto& listener) {
+        return seastar::keep_doing([&listener] () {
+            return listener.accept().then(
+                    [] (seastar::accept_result res) {
+                auto s = std::move(res.connection);
+                auto out = s.output();
+                return seastar::do_with(std::move(s), std::move(out),
+                        [] (auto& s, auto& out) {
+                    return out.write(canned_response).then([&out] {
+                        return out.close();
+                    });
+                });
+            });
+        });
+    });
+}
+
+seastar::future<> handle_connection_3(seastar::connected_socket s,
+                                    seastar::socket_address a) {
+    auto out = s.output();
+    auto in = s.input();
+    return do_with(std::move(s), std::move(out), std::move(in),
+            [] (auto& s, auto& out, auto& in) {
+        return seastar::repeat([&out, &in] {
+            return in.read().then([&out] (auto buf) {
+                if (buf) {
+                    return out.write(std::move(buf)).then([&out] {
+                        return out.flush();
+                    }).then([] {
+                        return seastar::stop_iteration::no;
+                    });
+                } else {
+                    return seastar::make_ready_future<seastar::stop_iteration>(
+                            seastar::stop_iteration::yes);
+                }
+            });
+        }).then([&out] {
+            return out.close();
+        });
+    });
+}
+
+seastar::future<> service_loop_3() {
+    seastar::listen_options lo;
+    lo.reuse_address = true;
+    return seastar::do_with(seastar::listen(seastar::make_ipv4_address({1234}), lo),
+            [] (auto& listener) {
+        return seastar::keep_doing([&listener] () {
+            return listener.accept().then(
+                    [] (seastar::accept_result res) {
+                // Note we ignore, not return, the future returned by
+                // handle_connection(), so we do not wait for one
+                // connection to be handled before accepting the next one.
+                (void)handle_connection_3(std::move(res.connection), std::move(res.remote_address)).handle_exception(
+                        [] (std::exception_ptr ep) {
+                    fmt::print(stderr, "Could not handle connection: {}\n", ep);
+                });
+            });
+        });
+    });
+}
+
+#include <seastar/core/app-template.hh>
+
+int main(int ac, char** av) {
+    seastar::app_template app;
+    return app.run(ac, av, [] {
+        std::cout << "This is the tutorial examples demo.  It is not running anything but rather makes sure the tutorial examples compile" << std::endl;
+        return seastar::make_ready_future<>();
+    });
+}