diff --git a/radio/processor/src/Buffer.hpp b/radio/processor/src/Buffer.hpp
index b7e1130..2fbdf6c 100644
--- a/radio/processor/src/Buffer.hpp
+++ b/radio/processor/src/Buffer.hpp
@@ -61,8 +61,8 @@ class Buffer : public IBuffer
 	T* data_w();
 	T* data_r();
 
-	size_t write(const T* pData, size_t len);
-	size_t read(T* pData, size_t len);
+	Result write(const T* pData, size_t len);
+	Result read(T* pData, size_t len);
 	T readAt(size_t offset);
 	Result consume(size_t len);
 	Result produce(size_t len);
diff --git a/radio/processor/src/Buffer.tcc b/radio/processor/src/Buffer.tcc
index 9e991a8..676e889 100644
--- a/radio/processor/src/Buffer.tcc
+++ b/radio/processor/src/Buffer.tcc
@@ -94,35 +94,35 @@ T* Buffer<T>::data_r()
 }
 
 template<typename T>
-size_t Buffer<T>::write(const T *pData, size_t len)
+typename Buffer<T>::Result Buffer<T>::write(const T *pData, size_t len)
 {
-	len = std::min(free(), len);
-	size_t numWritten = 0;
-
-	if (len == 0)
+	if (len > free())
 	{
-		throw Buffer::Exception(Result::Err_InvalidSize);
+		RETURN_OR_EXCEPT(Result::Err_InvalidSize);
 	}
 
+	size_t numWritten = 0;
 	while(len)
 	{
 		size_t num_remain = m_capacity - m_wi;
 		size_t actual_len = std::min(num_remain, len);
 
 		memcpy(data_w(), pData, actual_len*sizeof(T));
-		produce(actual_len);
 		len -= actual_len;
 		pData += actual_len;
 		numWritten += actual_len;
 	}
-	return numWritten;
-
+	return produce(numWritten);
 }
 
 template<typename T>
-size_t Buffer<T>::read(T* pData, size_t len)
+typename Buffer<T>::Result Buffer<T>::read(T* pData, size_t len)
 {
-	len = std::min(m_len, len);
+	if (len > m_len)
+	{
+		RETURN_OR_EXCEPT(Result::Err_InvalidSize);
+	}
+
 	size_t numRead = 0;
 	while(len)
 	{
@@ -134,15 +134,13 @@ size_t Buffer<T>::read(T* pData, size_t len)
 		pData += actual_len;
 		numRead += actual_len;
 	}
-	consume(numRead);
-	return numRead;
-
+	return consume(numRead);
 }
 
 template<typename T>
 T Buffer<T>::readAt(size_t offset)
 {
-	if (m_len < offset)
+	if (m_len < (1+offset))
 	{
 		throw Buffer::Exception(Result::Err_InvalidSize);
 	}
@@ -168,7 +166,7 @@ typename Buffer<T>::Result Buffer<T>::consume(size_t len)
 template<typename T>
 typename Buffer<T>::Result Buffer<T>::produce(size_t len)
 {
-	if (len > (m_capacity - m_len))
+	if (len > free())
 	{
 		RETURN_OR_EXCEPT(Result::Err_InvalidSize);
 	}