(Feat): Implement serial port HAL

src/dmx.cpp

@@ -2,62 +2,26 @@
 // Created by illyum on 8/15/2024.
 //
 
-#include "dmx.h"
-#include <iostream>
-#include <chrono>
-#include <thread>
-#include "windows.h"
 
-DMXEngine::DMXEngine(const char* portName, int baudRate, int dataSize)
-        : running(false), buffer(dataSize, 0) {
-    hSerial = CreateFileA(portName, GENERIC_WRITE, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
-    if (hSerial == INVALID_HANDLE_VALUE) {
-        std::cerr << "Error opening " << portName << " port" << std::endl;
+#include "dmx.h"
+#include "serial_port_factory.h"
+#include <iostream>
+#include <thread>
+
+DMXEngine::DMXEngine(const char* portName)
+        : running(false), buffer(DMX_CHANNELS, 0) {
+    serialPort = SerialPortFactory::createSerialPort();
+    if (!serialPort->open(portName, DMX_BAUD_RATE)) {
+        std::cerr << "Failed to open serial port" << std::endl;
         exit(EXIT_FAILURE);
     }
-
-    configurePort();
 }
 
 DMXEngine::~DMXEngine() {
     if (running) {
         stop();
     }
-    CloseHandle(hSerial);
-}
-
-void DMXEngine::configurePort() {
-    DCB dcbSerialParams = { 0 };
-    dcbSerialParams.DCBlength = sizeof(dcbSerialParams);
-    if (!GetCommState(hSerial, &dcbSerialParams)) {
-        std::cerr << "Error getting COM port state" << std::endl;
-        CloseHandle(hSerial);
-        exit(EXIT_FAILURE);
-    }
-
-    dcbSerialParams.BaudRate = 250000;
-    dcbSerialParams.ByteSize = 8;
-    dcbSerialParams.StopBits = TWOSTOPBITS;
-    dcbSerialParams.Parity = NOPARITY;
-
-    if (!SetCommState(hSerial, &dcbSerialParams)) {
-        std::cerr << "Error setting COM port state" << std::endl;
-        CloseHandle(hSerial);
-        exit(EXIT_FAILURE);
-    }
-
-    COMMTIMEOUTS timeouts = { 0 };
-    timeouts.ReadIntervalTimeout = 50;
-    timeouts.ReadTotalTimeoutConstant = 50;
-    timeouts.ReadTotalTimeoutMultiplier = 10;
-    timeouts.WriteTotalTimeoutConstant = 50;
-    timeouts.WriteTotalTimeoutMultiplier = 10;
-
-    if (!SetCommTimeouts(hSerial, &timeouts)) {
-        std::cerr << "Error setting COM port timeouts" << std::endl;
-        CloseHandle(hSerial);
-        exit(EXIT_FAILURE);
-    }
+    delete serialPort;
 }
 
 void DMXEngine::start() {
@@ -74,26 +38,21 @@ void DMXEngine::stop() {
     DMXEngine::dumpZeros();
 }
 
-
 void DMXEngine::setChannelValue(int channel, unsigned char value) {
-    if (channel >= 0 && channel < buffer.size()) {
+    if (channel >= 0 && channel < DMX_CHANNELS) {
         buffer[channel] = value;
     }
 }
 
 void DMXEngine::sendDMXData() {
     while (running) {
-        // Break condition
-        EscapeCommFunction(hSerial, SETBREAK);
-        std::this_thread::sleep_for(std::chrono::milliseconds(1));
-        EscapeCommFunction(hSerial, CLRBREAK);
+        serialPort->sendBreak();
         std::this_thread::sleep_for(std::chrono::milliseconds(1)); // MAB
 
-        DWORD bytesWritten;
-        unsigned char startCode = 0;
-        WriteFile(hSerial, &startCode, 1, &bytesWritten, NULL);
-        WriteFile(hSerial, buffer.data(), buffer.size(), &bytesWritten, NULL);
+        std::vector<unsigned char> data = {0}; // Start code
+        data.insert(data.end(), buffer.begin(), buffer.end());
 
+        serialPort->writeData(data);
         std::this_thread::sleep_for(std::chrono::milliseconds(25));
     }
 }
@@ -101,17 +60,16 @@ void DMXEngine::sendDMXData() {
 void DMXEngine::dumpZeros() {
     std::fill(buffer.begin(), buffer.end(), 0);
 
-    EscapeCommFunction(hSerial, SETBREAK);
-    std::this_thread::sleep_for(std::chrono::milliseconds(1));
-    EscapeCommFunction(hSerial, CLRBREAK);
+    serialPort->sendBreak();
     std::this_thread::sleep_for(std::chrono::milliseconds(1)); // MAB
 
-    DWORD bytesWritten;
-    unsigned char startCode = 0;
-    WriteFile(hSerial, &startCode, 1, &bytesWritten, NULL);
-    WriteFile(hSerial, buffer.data(), buffer.size(), &bytesWritten, NULL);
+    std::vector<unsigned char> data = {0}; // Start code
+    data.insert(data.end(), buffer.begin(), buffer.end());
+
+    serialPort->writeData(data);
 }
 
 void DMXEngine::dmxThreadFunc(DMXEngine* engine) {
     engine->sendDMXData();
 }
+

src/dmx.h

@@ -9,6 +9,9 @@
 #include <tuple>
 #include <atomic>
 #include <thread>
+#include "serial_port.h"
+
+const int DMX_BAUD_RATE = 250000;
 
 struct DMXFixture {
     unsigned char r, g, b;
@@ -17,7 +20,7 @@ struct DMXFixture {
 
 class DMXEngine {
 public:
-    explicit DMXEngine(const char* portName, int baudRate = 250000, int dataSize = 512);
+    DMXEngine(const char* portName);
     ~DMXEngine();
 
     void start();
@@ -25,15 +28,17 @@ public:
     void setChannelValue(int channel, unsigned char value);
 
 private:
+    void configurePort();
     void sendDMXData();
     void dumpZeros();
-    void configurePort();
     static void dmxThreadFunc(DMXEngine* engine);
 
-    void* hSerial;
-    std::atomic<bool> running;
+    SerialPort* serialPort;
     std::vector<unsigned char> buffer;
     std::thread dmxThread;
+    bool running;
+
+    static const int DMX_CHANNELS = 512;
 };
 
 #endif // DMX_H

src/serial_port.h

@@ -0,0 +1,22 @@
+//
+// Created by illyum on 8/16/2024.
+//
+
+#ifndef SERIAL_PORT_H
+#define SERIAL_PORT_H
+
+#include <string>
+#include <vector>
+
+class SerialPort {
+public:
+    virtual ~SerialPort() = default;
+
+    virtual bool open(const std::string& portName, int baudRate) = 0;
+    virtual void close() = 0;
+    virtual bool configure(int baudRate, int dataBits, int stopBits, int parity) = 0;
+    virtual bool writeData(const std::vector<unsigned char>& data) = 0;
+    virtual bool sendBreak() = 0;
+};
+
+#endif // SERIAL_PORT_H

src/serial_port_factory.h

@@ -0,0 +1,25 @@
+//
+// Created by illyum on 8/16/2024.
+//
+
+#ifndef SERIAL_PORT_FACTORY_H
+#define SERIAL_PORT_FACTORY_H
+
+#include "serial_port.h"
+
+#ifdef _WIN32
+#include "serial_port_windows.cpp"
+typedef WindowsSerialPort PlatformSerialPort;
+#elif defined(__linux__) || defined(__APPLE__)
+#include "serial_port_posix.cpp"
+typedef PosixSerialPort PlatformSerialPort;
+#endif
+
+class SerialPortFactory {
+public:
+    static SerialPort* createSerialPort() {
+        return new PlatformSerialPort();
+    }
+};
+
+#endif // SERIAL_PORT_FACTORY_H

src/serial_port_posix.cpp

@@ -0,0 +1,83 @@
+//
+// Created by illyum on 8/16/2024.
+//
+
+// FIXME:
+// I don't have a mac to test it on so... I have zero idea if
+// this will work, let alone compile
+
+#if defined(__linux__) || defined(__APPLE__)
+#include "serial_port.h"
+#include <fcntl.h>
+#include <unistd.h>
+#include <termios.h>
+#include <iostream>
+
+class PosixSerialPort : public SerialPort {
+public:
+    PosixSerialPort() : fd(-1) {}
+
+    ~PosixSerialPort() {
+        close();
+    }
+
+    bool open(const std::string& portName, int baudRate) override {
+        fd = ::open(portName.c_str(), O_RDWR | O_NOCTTY | O_NDELAY);
+        if (fd == -1) {
+            std::cerr << "Error opening " << portName << " port" << std::endl;
+            return false;
+        }
+        return configure(baudRate, CS8, 1, 0);
+    }
+
+    void close() override {
+        if (fd != -1) {
+            ::close(fd);
+            fd = -1;
+        }
+    }
+
+    bool configure(int baudRate, int dataBits, int stopBits, int parity) override {
+        struct termios options;
+        if (tcgetattr(fd, &options) < 0) {
+            std::cerr << "Error getting COM port attributes" << std::endl;
+            return false;
+        }
+
+        cfsetispeed(&options, baudRate);
+        cfsetospeed(&options, baudRate);
+
+        options.c_cflag &= ~CSIZE;
+        options.c_cflag |= dataBits;
+
+        options.c_cflag &= ~PARENB;
+        if (parity) options.c_cflag |= PARENB;
+
+        options.c_cflag &= ~CSTOPB;
+        if (stopBits == 2) options.c_cflag |= CSTOPB;
+
+        options.c_cflag |= CLOCAL | CREAD;
+
+        options.c_iflag &= ~(IXON | IXOFF | IXANY);
+        options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG);
+        options.c_oflag &= ~OPOST;
+
+        options.c_cc[VMIN] = 0;
+        options.c_cc[VTIME] = 5;
+
+        tcflush(fd, TCIFLUSH);
+        return tcsetattr(fd, TCSANOW, &options) == 0;
+    }
+
+    bool writeData(const std::vector<unsigned char>& data) override {
+        return ::write(fd, data.data(), data.size()) != -1;
+    }
+
+    bool sendBreak() override {
+        return tcsendbreak(fd, 0) == 0;
+    }
+
+private:
+    int fd;
+};
+#endif

src/serial_port_windows.cpp

@@ -0,0 +1,78 @@
+//
+// Created by illyum on 8/16/2024.
+
+#ifdef _WIN32
+#include "serial_port.h"
+#include <windows.h>
+#include <iostream>
+#include <thread>
+
+class WindowsSerialPort : public SerialPort {
+public:
+    WindowsSerialPort() : hSerial(INVALID_HANDLE_VALUE) {}
+
+    ~WindowsSerialPort() {
+        close();
+    }
+
+    bool open(const std::string& portName, int baudRate) override {
+        hSerial = CreateFileA(portName.c_str(), GENERIC_WRITE, 0, nullptr, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, nullptr);
+        if (hSerial == INVALID_HANDLE_VALUE) {
+            std::cerr << "Error opening " << portName << " port" << std::endl;
+            return false;
+        }
+        return configure(baudRate, 8, TWOSTOPBITS, NOPARITY);
+    }
+
+    void close() override {
+        if (hSerial != INVALID_HANDLE_VALUE) {
+            CloseHandle(hSerial);
+            hSerial = INVALID_HANDLE_VALUE;
+        }
+    }
+
+    bool configure(int baudRate, int dataBits, int stopBits, int parity) override {
+        DCB dcbSerialParams = { 0 };
+        dcbSerialParams.DCBlength = sizeof(dcbSerialParams);
+        if (!GetCommState(hSerial, &dcbSerialParams)) {
+            std::cerr << "Error getting COM port state" << std::endl;
+            return false;
+        }
+
+        dcbSerialParams.BaudRate = baudRate;
+        dcbSerialParams.ByteSize = dataBits;
+        dcbSerialParams.StopBits = stopBits;
+        dcbSerialParams.Parity = parity;
+
+        if (!SetCommState(hSerial, &dcbSerialParams)) {
+            std::cerr << "Error setting COM port state" << std::endl;
+            return false;
+        }
+
+        COMMTIMEOUTS timeouts = { 0 };
+        timeouts.ReadIntervalTimeout = 50;
+        timeouts.ReadTotalTimeoutConstant = 50;
+        timeouts.ReadTotalTimeoutMultiplier = 10;
+        timeouts.WriteTotalTimeoutConstant = 50;
+        timeouts.WriteTotalTimeoutMultiplier = 10;
+
+        return SetCommTimeouts(hSerial, &timeouts);
+    }
+
+    bool writeData(const std::vector<unsigned char>& data) override {
+        DWORD bytesWritten;
+        return WriteFile(hSerial, data.data(), data.size(), &bytesWritten, nullptr);
+    }
+
+    bool sendBreak() override {
+        EscapeCommFunction(hSerial, SETBREAK);
+        std::this_thread::sleep_for(std::chrono::milliseconds(1));
+        EscapeCommFunction(hSerial, CLRBREAK);
+        std::this_thread::sleep_for(std::chrono::milliseconds(1)); // MAB
+        return true;
+    }
+
+private:
+    HANDLE hSerial;
+};
+#endif