add server2

backend/src/main.cpp

@@ -1,12 +1,9 @@
-#include "event_loop.hpp"
+#include "server2.hpp"
+// #include "event_loop.hpp"
 #include "json.hpp"
 #include "mqtt.hpp"
-#include "server.hpp"
-#include <chrono>
-#include <cstdio>
-#include <iostream>
+// #include "server.hpp"
 #include <print>
-#include <span>
 #include <stdexcept>
 #include <string_view>
 #include <sys/select.h>
@@ -36,23 +33,23 @@ int main(void)
 
     mqtt_client.subscribe("/skateboard/update", [&](std::string_view text) {
         //
-        std::println("Skateboard: {}", text);
-        auto result = mst::json::parse(text);
-
-        if (!result) {
-            std::println(stderr,
-                "error: {} at {}",
-                result.error().message,
-                result.error().loc.idx);
-            return;
-        }
-        try {
-            auto parsed = std::move(result.value());
-            std::println(".rotation = {}",
-                parsed->query(".rotation").value()->get_f64());
-        } catch (std::runtime_error& ex) {
-            std::println(stderr, "exception: {}", ex.what());
-        }
+        // std::println("Skateboard: {}", text);
+        // auto result = mst::json::parse(text);
+        //
+        // if (!result) {
+        //     std::println(stderr,
+        //         "error: {} at {}",
+        //         result.error().message,
+        //         result.error().loc.idx);
+        //     return;
+        // }
+        // try {
+        //     auto parsed = std::move(result.value());
+        //     std::println(".rotation = {}",
+        //         parsed->query(".rotation").value()->get_f64());
+        // } catch (std::runtime_error& ex) {
+        //     std::println(stderr, "exception: {}", ex.what());
+        // }
     });
 
     auto mqtt_thread = std::thread([&]() {
@@ -64,16 +61,19 @@ int main(void)
         }
     });
 
-    auto mgr = mst::event::Manager::create().value();
-    auto x = mst::Server::bind(mgr, "0.0.0.0", PORT);
-    if (!x) {
-        std::println("{}", x.error());
-        return 1;
-    }
-    std::println("starting");
-    {
-        auto x = mgr.start();
-    }
+    // auto mgr = mst::event::Manager::create().value();
+    // auto x = mst::Server::bind(mgr, "0.0.0.0", PORT);
+    // if (!x) {
+    //     std::println("{}", x.error());
+    //     return 1;
+    // }
+    // std::println("starting");
+    // {
+    //     auto x = mgr.start();
+    // }
+
+    auto server = mst::server2::Server();
+    server.listen();
 
     mqtt_thread.join();
     return 0;

backend/src/mqtt.cpp

@@ -218,7 +218,7 @@ void Client::cb_publish()
 
 void Client::cb_message(std::string_view topic, const void* data, size_t size)
 {
-    std::println("[MQTT] Message received");
+    // std::println("[MQTT] Message received");
 
     auto text = std::string_view(static_cast<const char*>(data), size);
 

backend/src/server2.cpp

@@ -0,0 +1,175 @@
+#include "server2.hpp"
+#include <algorithm>
+#include <cerrno>
+#include <cstdint>
+#include <cstring>
+#include <format>
+#include <iterator>
+#include <netdb.h>
+#include <poll.h>
+#include <print>
+#include <sys/poll.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <vector>
+
+namespace {
+using namespace mst::server2;
+
+auto get_listener_socket() -> int
+{
+    int listener; // Listening socket descriptor
+    int status;
+
+    struct addrinfo hints = { };
+    hints.ai_family = AF_INET;
+    hints.ai_socktype = SOCK_STREAM;
+    hints.ai_flags = AI_PASSIVE;
+
+    struct addrinfo* addr;
+
+    if ((status = ::getaddrinfo(NULL, "8881", &hints, &addr)) != 0)
+        throw Error(std::format("getaddrinfo ({})", ::gai_strerror(status)));
+
+    struct addrinfo* p;
+    for (p = addr; p != NULL; p = p->ai_next) {
+        listener = ::socket(p->ai_family, p->ai_socktype, p->ai_protocol);
+        if (listener < 0) {
+            continue;
+        }
+
+        int reuseaddr_opt = 1;
+        ::setsockopt(
+            listener, SOL_SOCKET, SO_REUSEADDR, &reuseaddr_opt, sizeof(int));
+
+        if (::bind(listener, p->ai_addr, p->ai_addrlen) < 0) {
+            ::close(listener);
+            continue;
+        }
+
+        break;
+    }
+
+    if (p == NULL)
+        throw Error("didn't get bound");
+
+    ::freeaddrinfo(addr);
+
+    if (::listen(listener, 10) == -1)
+        throw Error(std::format("could not listen ({})", strerror(errno)));
+
+    return listener;
+}
+
+}
+
+namespace mst::server2 {
+
+struct Server::State {
+    std::vector<::pollfd> pollfds;
+    std::vector<::pollfd> queued_insertions;
+    std::vector<std::size_t> queued_deletions;
+};
+
+Server::Server()
+    : m_state(std::make_unique<State>())
+{
+}
+Server::~Server() = default;
+
+void Server::listen()
+{
+    m_listener_fd = get_listener_socket();
+    m_state->pollfds.push_back(::pollfd {
+        .fd = m_listener_fd,
+        .events = POLLIN,
+        .revents = { },
+    });
+
+    std::println("[mst::server2] listening for connections");
+
+    while (true) {
+        int poll_count
+            = ::poll(m_state->pollfds.data(), m_state->pollfds.size(), -1);
+
+        if (poll_count == -1)
+            throw Error(std::format("poll (%s)", strerror(errno)));
+
+        for (size_t i = 0; i < m_state->pollfds.size(); ++i) {
+            auto& fd = m_state->pollfds[i];
+            if (!(fd.revents & (POLLIN | POLLHUP)))
+                continue;
+
+            if (fd.fd == m_listener_fd) {
+                create_connection();
+            } else {
+                try {
+                    handle_request(i);
+                } catch (Error& ex) {
+                    std::println(stderr,
+                        "[mst::server2] exception in handler for client {}: {}",
+                        fd.fd,
+                        ex.what());
+                    m_state->queued_deletions.push_back(i);
+                }
+            }
+        }
+
+        auto& fds = m_state->pollfds;
+        auto& deletions = m_state->queued_deletions;
+
+        std::reverse(deletions.begin(), deletions.end());
+        for (auto idx : deletions) {
+            fds.erase(std::next(fds.begin(), static_cast<long>(idx)));
+        }
+        m_state->queued_deletions.clear();
+
+        for (auto& fd : m_state->queued_insertions) {
+            m_state->pollfds.push_back(fd);
+        }
+        m_state->queued_insertions.clear();
+    }
+}
+
+void Server::create_connection()
+{
+    struct sockaddr_storage remoteaddr;
+    socklen_t addrlen = sizeof remoteaddr;
+
+    int client_fd
+        = ::accept(m_listener_fd, (struct sockaddr*)&remoteaddr, &addrlen);
+
+    if (client_fd == -1)
+        throw Error(std::format("format ({})", strerror(errno)));
+
+    std::println("[mst::server2] client {} connected", client_fd);
+
+    m_state->queued_insertions.push_back(::pollfd {
+        .fd = client_fd,
+        .events = POLLIN,
+        .revents = { },
+    });
+}
+
+void Server::handle_request(size_t i)
+{
+    auto& client_fd = m_state->pollfds[i].fd;
+    auto buffer = std::vector<char>(512);
+
+    ssize_t byte_count = ::recv(client_fd, buffer.data(), buffer.size(), 0);
+
+    if (byte_count <= 0)
+        throw Error(std::format("recv: {}", strerror(errno)));
+
+    if (byte_count == 0) {
+        std::println("[mst::server2] client {} disconnected", client_fd);
+
+        m_state->queued_deletions.push_back(i);
+        return;
+    }
+
+    std::println("[mst::server2] received: {:s}", buffer);
+}
+
+}

backend/src/server2.hpp

@@ -0,0 +1,29 @@
+#pragma once
+
+#include <memory>
+#include <stdexcept>
+
+namespace mst::server2 {
+
+struct Error : public std::runtime_error {
+    using std::runtime_error::runtime_error;
+};
+
+class Server {
+public:
+    explicit Server();
+    ~Server();
+
+    void listen();
+
+private:
+    struct State;
+
+    void create_connection();
+    void handle_request(size_t i);
+
+    int m_listener_fd { };
+    std::unique_ptr<State> m_state { nullptr };
+};
+
+}

backend/src/tcp.cpp

@@ -42,8 +42,8 @@ auto TcpListener::bind(const std::string& host, uint16_t port)
 
     struct sockaddr_in address = {
         .sin_family = AF_INET,
-        .sin_port = htons(port),
-        .sin_addr = in_addr { .s_addr = inet_addr(host.c_str()) },
+        .sin_port = ::htons(port),
+        .sin_addr = in_addr { .s_addr = ::inet_addr(host.c_str()) },
         .sin_zero = { },
     };