Added Stream::indexOf(char c) that finds a character in a stream

without advancing the internal stream pointers.

Fixes: #1214.

Sming/SmingCore/HardwareSerial.cpp

@@ -290,5 +290,28 @@ HardwareSerial::operator bool() const
     return uart != 0;
 }
 
+size_t HardwareSerial::indexOf(char c)
+{
+	int offset = uart->rx_buffer->rpos;
+	int pos = 0;
+	while(pos < available()) {
+		if(uart->rx_buffer->buffer[offset + pos] == c) {
+			return pos;
+		}
+
+		pos++;
+
+		if(pos + offset == uart->rx_buffer->wpos) {
+			break;
+		}
+
+		if(pos + offset == uart->rx_buffer->size) {
+			offset = -pos;
+		}
+	}
+
+	return -1;
+}
+
 
 HardwareSerial Serial(UART_ID_0);

Sming/SmingCore/HardwareSerial.h

@@ -252,6 +252,13 @@ class HardwareSerial : public Stream
 	 */
 	operator bool() const;
 
+	/*
+	 * @brief Returns the location of the searched character
+	 * @param char c - character to search for
+	 * @retval size_t -1 if not found 0 or positive number otherwise
+	 */
+	size_t indexOf(char c);
+
 private:
 	int uartNr;
 	static HWSerialMemberData memberData[NUMBER_UARTS];

Sming/Wiring/Stream.h

@@ -76,6 +76,15 @@ class Stream : public Print
     // Wiring String functions to be added here
     String readString();
     String readStringUntil(char terminator);
+
+    /*
+    * @brief Returns the location of the searched character
+    * @param char c - character to search for
+    * @retval size_t -1 if not found 0 or positive number otherwise
+    */
+    virtual size_t indexOf(char c) {
+    	return -1;
+    }
 
   protected:
     long parseInt(char skipChar); // as above but the given skipChar is ignored

samples/Basic_rBoot/app/application.cpp

@@ -98,10 +98,10 @@ void ShowInfo() {
 }
 
 void serialCallBack(Stream& stream, char arrivedChar, unsigned short availableCharsCount) {
-
-	if (arrivedChar == '\n') {
-		char str[availableCharsCount];
-		for (int i = 0; i < availableCharsCount; i++) {
+	int pos = stream.indexOf('\n');
+	if(pos > -1) {
+		char str[pos + 1];
+		for (int i = 0; i < pos + 1; i++) {
 			str[i] = stream.read();
 			if (str[i] == '\r' || str[i] == '\n') {
 				str[i] = '\0';