Merge pull request #34 from gbmhunter/develop

Release of v2.6.0.

Author: gbmhunter

CHANGELOG.md

@@ -5,6 +5,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [v2.6.0] - 2023-02-02
+
+- `Read()` and `ReadBinary()` now throw exceptions if they detect that the serial device has been disconnected (thanks to [aldoshkind](https://github.com/aldoshkind) for helping with this one).
+- Added Arduino testing instructions to the README.
+
 ## [v2.5.0] - 2022-11-12
 
 - Replaced all tabs in code with spaces, which should fix the ugly code rendering in GitHub.

README.md

@@ -143,7 +143,47 @@ Attaching the Arduino Uno (need to be done with Admin priviliges the first time
 usbipd wsl attach --busid=1-5
 ```
 
-`/dev/ttyACM0` now appears inside WSL, and you can use CppLinuxSerial with this device like usual.
+`/dev/ttyACM0` now appears inside WSL, and you can use `CppLinuxSerial` with this device like usual.
+
+NOTE: Sometimes `/dev/ttyACM0` is not part of the dialout group, so even with your user being part of that group, you will get permission denied errors when trying to access the serial port. Sometimes using `chmod` to change the permissions works:
+
+```
+sudo chmod 666 /dev/ttyACM0 
+```
+
+## Tests
+
+### Prerequisties
+
+Install arduino:avr platform:
+
+```
+$ arduino-cli core install arduino:avr
+```
+
+Detect attached Arduino boards with:
+
+```
+$ arduino-cli board list
+```
+
+Compile:
+
+```
+arduino-cli compile --fqbn arduino:avr:uno Basic/
+```
+
+Upload:
+
+```
+arduino-cli upload -p /dev/ttyACM0 --fqbn arduino:avr:uno Basic/
+```
+
+### Running
+
+```
+g++ main.cpp -lCppLinuxSerial
+```
 
 ## Changelog
 

include/CppLinuxSerial/SerialPort.hpp

@@ -175,14 +175,19 @@ namespace mn {
             /// \param      data        The object the read characters from the COM port will be saved to.
             /// \param      wait_ms     The amount of time to wait for data. Set to 0 for non-blocking mode. Set to -1
             ///                 to wait indefinitely for new data.
-            /// \throws     CppLinuxSerial::Exception if state != OPEN.
+            /// \note       Use ReadBinary() if you want to interpret received data as binary.
+            /// \throws     
+            ///             CppLinuxSerial::Exception if state != OPEN.
+            ///             std::system_error() if device has been disconnected.
             void Read(std::string& data);
 
             /// \brief      Use to read binary data from the COM port.
             /// \param      data        The object the read uint8_t bytes from the COM port will be saved to.
             /// \param      wait_ms     The amount of time to wait for data. Set to 0 for non-blocking mode. Set to -1
             ///                 to wait indefinitely for new data.
+            /// \note       Use Read() if you want to interpret received data as a string.
             /// \throws     CppLinuxSerial::Exception if state != OPEN.
+            ///             std::system_error() if device has been disconnected.
             void ReadBinary(std::vector<uint8_t>& data);
 
             /// \brief		Use to get number of bytes available in receive buffer.

src/SerialPort.cpp

@@ -538,8 +538,16 @@ namespace CppLinuxSerial {
             // Read was unsuccessful
             throw std::system_error(EFAULT, std::system_category());
         }
+        else if(n == 0) {
+            // n == 0 means EOS, but also returned on device disconnection. We try to get termios2 to distinguish two these two states
+            struct termios2 term2;
+            int rv = ioctl(fileDesc_, TCGETS2, &term2);
 
-        if(n > 0) {
+            if(rv != 0) {
+                throw std::system_error(EFAULT, std::system_category());
+            }
+        }
+        else if(n > 0) {
             data = std::string(&readBuffer_[0], n);
         }
 
@@ -567,8 +575,16 @@ namespace CppLinuxSerial {
             // Read was unsuccessful
             throw std::system_error(EFAULT, std::system_category());
         }
+        else if(n == 0) {
+            // n == 0 means EOS, but also returned on device disconnection. We try to get termios2 to distinguish two these two states
+            struct termios2 term2;
+            int rv = ioctl(fileDesc_, TCGETS2, &term2);
 
-        if(n > 0) {
+            if(rv != 0) {
+                throw std::system_error(EFAULT, std::system_category());
+            }
+        }
+        else if(n > 0) {
             copy(readBuffer_.begin(), readBuffer_.begin() + n, back_inserter(data));
         }
 

test/arduino/main.cpp

@@ -2,6 +2,15 @@
 
 using namespace mn::CppLinuxSerial;
 
+// Overload to be able to print vectors to std::cout
+template <typename T>
+std::ostream& operator<<( std::ostream& ostrm, const std::vector<T>& vec ){
+    for( int j = 0, n = vec.size(); j < n; ++j ){
+        ostrm << ",["[ !j ] << " " << vec[ j ];
+    }
+    return ostrm << " ]";
+}
+
 int main() {
 	// Create serial port object and open serial port
     SerialPort serialPort("/dev/ttyACM0", BaudRate::B_9600, NumDataBits::EIGHT, Parity::NONE, NumStopBits::ONE);
@@ -13,9 +22,16 @@ int main() {
 	// serialPort0.Write("Hello");
 
 	// Read some data back
+    // while(1) {
+    //     std::string readData;
+    //     serialPort.Read(readData);
+    //     std::cout << "Received data: " << readData;
+    // }
+
+	// Read some data back (raw)
     while(1) {
-        std::string readData;
-        serialPort.Read(readData);
+        std::vector<unsigned char> readData;
+        serialPort.ReadBinary(readData);
         std::cout << "Received data: " << readData;
     }