Add macOS USB UART support

src/SerialReader.cpp

@@ -10,38 +10,70 @@
 #include <termios.h>
 #include <unistd.h>
 
+#ifdef Q_OS_MACOS
+#include <IOKit/serial/ioss.h>
+#endif
+
 namespace {
 
 constexpr qsizetype MaxBytesPerReadCycle = 64 * 1024;
 
-speed_t baudToSpeed(int baudRate)
+bool applyBaudRate(termios &options, int baudRate)
 {
+    speed_t speed = 0;
     switch (baudRate) {
     case 1200:
-        return B1200;
+        speed = B1200;
+        break;
     case 2400:
-        return B2400;
+        speed = B2400;
+        break;
     case 4800:
-        return B4800;
+        speed = B4800;
+        break;
     case 9600:
-        return B9600;
+        speed = B9600;
+        break;
     case 19200:
-        return B19200;
+        speed = B19200;
+        break;
     case 38400:
-        return B38400;
+        speed = B38400;
+        break;
     case 57600:
-        return B57600;
+        speed = B57600;
+        break;
     case 115200:
-        return B115200;
+        speed = B115200;
+        break;
+#ifdef B230400
     case 230400:
-        return B230400;
+        speed = B230400;
+        break;
+#endif
+#ifdef B460800
     case 460800:
-        return B460800;
+        speed = B460800;
+        break;
+#endif
+#ifdef B921600
     case 921600:
-        return B921600;
+        speed = B921600;
+        break;
+#endif
     default:
-        return 0;
+#ifdef Q_OS_MACOS
+        // IOSSIOSPEED below applies the exact requested rate. A valid termios
+        // placeholder is still required before that ioctl can be issued.
+        speed = B9600;
+        break;
+#else
+        return false;
+#endif
     }
+
+    return ::cfsetispeed(&options, speed) == 0
+        && ::cfsetospeed(&options, speed) == 0;
 }
 
 } // namespace
@@ -176,12 +208,6 @@ void SerialReader::flushPartialLine()
 
 bool SerialReader::configurePort(int baudRate)
 {
-    const speed_t speed = baudToSpeed(baudRate);
-    if (speed == 0) {
-        emit errorOccurred(QStringLiteral("Desteklenmeyen baud rate: %1").arg(baudRate));
-        return false;
-    }
-
     termios options {};
     if (::tcgetattr(m_fd, &options) != 0) {
         emitSystemError(QStringLiteral("Port ayarlari okunamadi"));
@@ -189,8 +215,10 @@ bool SerialReader::configurePort(int baudRate)
     }
 
     ::cfmakeraw(&options);
-    ::cfsetispeed(&options, speed);
-    ::cfsetospeed(&options, speed);
+    if (!applyBaudRate(options, baudRate)) {
+        emit errorOccurred(QStringLiteral("Bu sistemde desteklenmeyen baud rate: %1").arg(baudRate));
+        return false;
+    }
 
     options.c_cflag |= CLOCAL | CREAD;
     options.c_cflag &= ~HUPCL;
@@ -206,6 +234,14 @@ bool SerialReader::configurePort(int baudRate)
         return false;
     }
 
+#ifdef Q_OS_MACOS
+    speed_t requestedSpeed = static_cast<speed_t>(baudRate);
+    if (::ioctl(m_fd, IOSSIOSPEED, &requestedSpeed) != 0) {
+        emitSystemError(QStringLiteral("macOS baud rate uygulanamadi"));
+        return false;
+    }
+#endif
+
     ::tcflush(m_fd, TCIFLUSH);
     return true;
 }