linux_serial_minial driver - code improvements

src/drivers/linux_serial_minimal.c

@@ -99,6 +99,7 @@ static void setup_bit_size(struct termios* tty, __po_hi_c_serial_conf_t* serialc
    }
    else
    {
+       __PO_HI_DEBUG_DEBUG("Setting bit 8\n");
        tty->c_cflag |= CS8;
    }
 }
@@ -184,20 +185,27 @@ static void setup_termios(struct termios* tty, __po_hi_device_id id)
 #define PACKET_STOP_BYTE '\x03'
 #define PACKET_ESCAPE_BYTE '\x1B'
 
-static int encode_packet(uint8_t* data, const uint8_t* msg_content, const int msg_length)
+// process packet data generated by PolyORB to send it using UART
+static int encode_packet(uint8_t* data, const int data_length, const uint8_t* msg_content, const int msg_length)
 {
     if(msg_length <= 8)
     {
-        __PO_HI_DEBUG_DEBUG ("Encoding packet Not enaugh msg_length, %d\n", msg_length);
+        __PO_HI_DEBUG_DEBUG ("Encoding packet - not enough msg_length, at least 9 bytes is required, got %d\n", msg_length);
         // the message is empty
         return 0;
     }
 
-    // first four bytes of msg_content - port
-    uint8_t* data_ptr = (uint8_t*) (msg_content + 4); // skip port to access data
+    // first four bytes of msg_content - port number
+    uint8_t* data_ptr = (uint8_t*) (msg_content + 4); // skip port number to access data
     // last four bytes of msg_content - actual msg length
     uint32_t* length_ptr = (uint32_t*)(msg_content + (msg_length - 4));
 
+    if(data_length < *length_ptr * 2 + 2)
+    {
+        __PO_HI_DEBUG_CRITICAL ("Encoding packet - not enough data_length, at least %d bytes is required, got %d\n", *length_ptr, data_length);
+        return 0;
+    }
+
     int length = 0;
 
     data[length++] = PACKET_START_BYTE;
@@ -470,8 +478,9 @@ int  __po_hi_c_driver_linux_serial_minimal_sender (__po_hi_task_id task_id, __po
                         0,
                         msg_length);
 
-   uint8_t* data = (uint8_t*)malloc(msg_length * 2 + 1);
-   int length = encode_packet(data, msg_content, msg_length);
+   int data_length = msg_length * 2 + 2;
+   uint8_t* data = (uint8_t*)malloc(data_length);
+   int length = encode_packet(data, data_length, msg_content, msg_length);
 
    if(length > 0)
    {