First TCP communicator

CMakeLists.txt

@@ -23,5 +23,5 @@ set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_VISIBILITY_PRESET hidden)
 
 
-add_executable(sender main.cpp grbl.h grbl.cpp grbl_test.cpp)
+add_executable(sender main.cpp grbl.h grbl.cpp grbl_test.cpp grbl_communication.h grbl_communication.cpp)
 target_link_libraries(sender nanogui gtest gtest_main)

grbl_communication.cpp

@@ -0,0 +1,119 @@
+#include "grbl_communication.h"
+
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+#include <iostream>
+#include <fcntl.h>
+#include <chrono>
+
+grbl::tcp_transport::tcp_transport(std::string address, uint16_t p)
+        : ip{std::move(address)}, port{p} {
+    live_check_thread = std::thread(&grbl::tcp_transport::worker, this);
+}
+
+void grbl::tcp_transport::open(grbl::transport_callbacks& cb) {
+    if (is_connected) {
+        close();
+    }
+
+    listener = &cb;
+    fd = socket(AF_INET, SOCK_STREAM, 0);
+    if (fd == -1) {
+        std::cerr << "Error creating socket" << std::endl;
+    }
+
+    struct sockaddr_in serv_addr{};
+    serv_addr.sin_family = AF_INET;
+    serv_addr.sin_port = htons(port);
+
+    if (inet_pton(AF_INET, ip.c_str(), &serv_addr.sin_addr) <= 0) {
+        std::cerr << "Invalid address/ Address not supported" << std::endl;
+        return;
+    }
+
+    auto status = connect(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr));
+    if (status < 0) {
+        std::cerr << "Connection failed";
+        return;
+    }
+
+    is_connected = true;
+    listener->on_connected(this);
+
+    // set non-blocking please, after we connected
+    fcntl(fd, F_SETFL, O_NONBLOCK);
+}
+
+void grbl::tcp_transport::close() {
+    if (fd >= 0) {
+        ::close(fd);
+
+        is_connected = false;
+        send_queue = std::queue<std::string>{};
+
+        if (listener != nullptr)
+            listener->on_disconnected(this);
+    }
+}
+
+void grbl::tcp_transport::send(std::string line) {
+    if (is_connected) {
+        send_queue.push(line + "\r");
+    }
+}
+
+void grbl::tcp_transport::worker() {
+    std::string received;
+    uint8_t buffer[200];
+
+    while (!should_quit) {
+        if (is_connected) {
+            // anything to write?
+            if (!send_queue.empty()) {
+                auto line = send_queue.front();
+                auto result = write(fd, line.c_str(), line.size());
+                if (result == -1) {
+                    std::cerr << "Failed while writing." << std::endl;
+                    close();
+                }
+
+                send_queue.pop();
+            }
+
+            // anything to read?
+            auto read_bytes = read(fd, buffer, 200);
+            if (read_bytes > 0) {
+                for (int i = 0; i < read_bytes; i++) {
+                    auto is_eol = buffer[i] == '\r' || buffer[i] == '\n';
+                    if (is_eol) {
+                        if (!is_empty_line(received)) {
+                            listener->on_line_received(received, this);
+                        }
+                        received.clear();
+                    } else {
+                        received.push_back(static_cast<char>(buffer[i]));
+                    }
+                }
+            }
+
+            // give some time to others
+            std::this_thread::sleep_for(std::chrono::milliseconds(100));
+        }
+    }
+}
+
+grbl::tcp_transport::~tcp_transport() {
+    close();
+    should_quit = true;
+    live_check_thread.join();
+}
+
+bool grbl::tcp_transport::is_empty_line(std::string line) {
+    for (auto& c: line) {
+        if (c != '\r' && c != '\n' && c != ' ') {
+            return false;
+        }
+    }
+    return true;
+}

grbl_communication.h

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <string>
+#include <thread>
+#include <queue>
+
+namespace grbl {
+
+struct transport;
+
+struct transport_callbacks {
+    virtual void on_connected(transport*) = 0;
+    virtual void on_disconnected(transport*) = 0;
+    virtual void on_line_received(std::string line, transport* ) = 0;
+};
+
+struct transport {
+    virtual void open(transport_callbacks& cb) = 0;
+    virtual void close() = 0;
+    virtual void send(std::string line) = 0;
+};
+
+struct tcp_transport : public transport {
+    virtual ~tcp_transport();
+    tcp_transport(std::string address, uint16_t port);
+
+    void open(transport_callbacks& cb) override;
+    void close() override;
+    void send(std::string line) override;
+
+private:
+
+    void worker();
+
+    std::string ip;
+    uint16_t port;
+    transport_callbacks *listener = nullptr;
+    int fd = -1;
+    volatile bool is_connected = false;
+    std::thread live_check_thread;
+    std::queue<std::string> send_queue;
+    volatile bool should_quit = false;
+    bool is_empty_line(std::string line);
+};
+
+}
+

main.cpp

@@ -50,6 +50,7 @@
 #include <stb_image.h>
 #include "grbl.h"
 #include <gtest/gtest.h>
+#include "grbl_communication.h"
 
 using namespace nanogui;
 
@@ -611,8 +612,29 @@ private:
     int m_current_image;
 };
 
+
+struct grbl_listener : public grbl::transport_callbacks {
+    void on_connected(grbl::transport *t) override {
+        std::cout << "Listener: connected!" << std::endl;
+        t->send("$$");
+    }
+
+    void on_disconnected(grbl::transport *t) override {
+        std::cout << "Listener: disconnected!" << std::endl;
+    }
+
+    void on_line_received(std::string line, grbl::transport *t) override {
+        std::cout << "Listener: -> " << line << std::endl;
+    }
+};
+
 int main(int argc, char **argv) {
 
+    grbl_listener listener{};
+
+    grbl::tcp_transport transport("192.168.5.39", 23);
+    transport.open(listener);
+
     testing::InitGoogleTest(&argc, argv);
     auto result = RUN_ALL_TESTS();
     if (result) {
@@ -621,9 +643,9 @@ int main(int argc, char **argv) {
 
     try {
 
-        grbl::program pgm;
-        pgm.load("./program.nc");
-        pgm.dump(std::cout);
+//        grbl::program pgm;
+//        pgm.load("./program.nc");
+//        pgm.dump(std::cout);
 
         nanogui::init();