AP_HAL_Linux: added UARTDevice

libraries/AP_HAL_Linux/UARTDevice.cpp

@@ -0,0 +1,123 @@
+#include <AP_HAL.h>
+
+#if CONFIG_HAL_BOARD == HAL_BOARD_LINUX
+
+#include <termios.h>
+#include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <poll.h>
+
+#include "UARTDevice.h"
+
+#include <termios.h>
+#include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <poll.h>
+
+UARTDevice::UARTDevice(const char *device_path): 
+    _device_path(device_path)
+{
+}
+
+UARTDevice::~UARTDevice()
+{
+
+}
+
+bool UARTDevice::close()
+{
+    if (_fd != -1) {
+        if (::close(_fd) < 0) {
+            return false;
+        }
+    }
+
+    _fd = -1;
+
+    return true;
+}
+
+bool UARTDevice::open()
+{
+    _fd = ::open(_device_path, O_RDWR | O_CLOEXEC);
+
+    if (_fd < 0) {
+        ::fprintf(stderr, "Failed to open UART device %s - %s\n",
+                  _device_path, strerror(errno));
+        return false;
+    }
+
+    _disable_crlf();
+
+    return true;
+}
+
+ssize_t UARTDevice::read(uint8_t *buf, uint16_t n)
+{
+    return ::read(_fd, buf, n);
+}
+
+ssize_t UARTDevice::write(const uint8_t *buf, uint16_t n)
+{
+    struct pollfd fds;
+    fds.fd = _fd;
+    fds.events = POLLOUT;
+    fds.revents = 0;
+
+    int ret = 0;
+
+    if (poll(&fds, 1, 0) == 1) {
+        ret = ::write(_fd, buf, n);
+    }
+
+    return ret;
+}
+
+void UARTDevice::set_blocking(bool blocking)
+{
+    int flags = fcntl(_fd, F_GETFL, 0);
+    
+    if (blocking) {
+        flags = flags & ~O_NONBLOCK;
+    } else {
+        flags = flags | O_NONBLOCK;
+    }
+
+    if (fcntl(_fd, F_SETFL, flags) < 0) {
+        ::fprintf(stderr, "Failed to make UART nonblocking %s - %s\n",
+                  _device_path, strerror(errno));
+    }
+
+}
+
+void UARTDevice::_disable_crlf()
+{
+    struct termios t;
+    memset(&t, 0, sizeof(t));
+
+    tcgetattr(_fd, &t);
+
+    // disable LF -> CR/LF
+    t.c_iflag &= ~(BRKINT | ICRNL | IMAXBEL | IXON | IXOFF);
+    t.c_oflag &= ~(OPOST | ONLCR);
+    t.c_lflag &= ~(ISIG | ICANON | IEXTEN | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE);
+    t.c_cc[VMIN] = 0;
+
+    tcsetattr(_fd, TCSANOW, &t);
+}
+
+void UARTDevice::set_speed(uint32_t baudrate)
+{
+    struct termios t;
+    memset(&t, 0, sizeof(t));
+
+    tcgetattr(_fd, &t);
+    cfsetspeed(&t, baudrate);
+    tcsetattr(_fd, TCSANOW, &t);
+}
+
+#endif

libraries/AP_HAL_Linux/UARTDevice.h

@@ -0,0 +1,26 @@
+#ifndef __AP_HAL_LINUX_UARTDEVICE_UDP_H__
+#define __AP_HAL_LINUX_UARTDEVICE_UDP_H__
+
+#include "SerialDevice.h"
+#include "../AP_HAL/utility/Socket.h"
+
+class UARTDevice: public SerialDevice {
+public:
+    UARTDevice(const char *device_path);
+    virtual ~UARTDevice();
+
+    virtual bool open() override;
+    virtual bool close() override;
+    virtual ssize_t write(const uint8_t *buf, uint16_t n) override;
+    virtual ssize_t read(uint8_t *buf, uint16_t n) override;
+    virtual void set_blocking(bool blocking) override;
+    virtual void set_speed(uint32_t speed) override;
+
+private:
+    void _disable_crlf();
+
+    int _fd = -1;
+    const char *_device_path;
+};
+
+#endif