diff --git a/include/freerdp/utils/ringbuffer.h b/include/freerdp/utils/ringbuffer.h
index 1ec00c514..b22b30786 100644
--- a/include/freerdp/utils/ringbuffer.h
+++ b/include/freerdp/utils/ringbuffer.h
@@ -25,6 +25,8 @@
 #define __RINGBUFFER_H___
 
 #include <winpr/wtypes.h>
+#include <freerdp/api.h>
+
 
 /** @brief ring buffer meta data */
 struct _RingBuffer {
@@ -45,28 +47,32 @@ struct _DataChunk {
 };
 typedef struct _DataChunk DataChunk;
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /** initialise a ringbuffer
  * @param initialSize the initial capacity of the ringBuffer
  * @return if the initialisation was successful
  */
-BOOL ringbuffer_init(RingBuffer *rb, size_t initialSize);
+FREERDP_API BOOL ringbuffer_init(RingBuffer *rb, size_t initialSize);
 
 /** destroys internal data used by this ringbuffer
  * @param ringbuffer
  */
-void ringbuffer_destroy(RingBuffer *ringbuffer);
+FREERDP_API void ringbuffer_destroy(RingBuffer *ringbuffer);
 
 /** computes the space used in this ringbuffer
  * @param ringbuffer
  * @return the number of bytes stored in that ringbuffer
  */
-size_t ringbuffer_used(const RingBuffer *ringbuffer);
+FREERDP_API size_t ringbuffer_used(const RingBuffer *ringbuffer);
 
 /** returns the capacity of the ring buffer
  * @param ringbuffer
  * @return the capacity of this ring buffer
  */
-size_t ringbuffer_capacity(const RingBuffer *ringbuffer);
+FREERDP_API size_t ringbuffer_capacity(const RingBuffer *ringbuffer);
 
 /** writes some bytes in the ringbuffer, if the data doesn't fit, the ringbuffer
  * is resized automatically
@@ -76,7 +82,7 @@ size_t ringbuffer_capacity(const RingBuffer *ringbuffer);
  * @param sz the size of the data to add
  * @return if the operation was successful, it could fail in case of OOM during realloc()
  */
-BOOL ringbuffer_write(RingBuffer *rb, const BYTE *ptr, size_t sz);
+FREERDP_API BOOL ringbuffer_write(RingBuffer *rb, const BYTE *ptr, size_t sz);
 
 
 /** ensures that we have sz bytes available at the write head, and return a pointer
@@ -86,7 +92,7 @@ BOOL ringbuffer_write(RingBuffer *rb, const BYTE *ptr, size_t sz);
  * @param sz the size to ensure
  * @return a pointer on the write head, or NULL in case of OOM
  */
-BYTE *ringbuffer_ensure_linear_write(RingBuffer *rb, size_t sz);
+FREERDP_API BYTE *ringbuffer_ensure_linear_write(RingBuffer *rb, size_t sz);
 
 /** move ahead the write head in case some byte were written directly by using
  * a pointer retrieved via ringbuffer_ensure_linear_write(). This function is
@@ -97,7 +103,7 @@ BYTE *ringbuffer_ensure_linear_write(RingBuffer *rb, size_t sz);
  * @param sz the number of bytes that have been written
  * @return if the operation was successful, FALSE is sz is too big
  */
-BOOL ringbuffer_commit_written_bytes(RingBuffer *rb, size_t sz);
+FREERDP_API BOOL ringbuffer_commit_written_bytes(RingBuffer *rb, size_t sz);
 
 
 /** peeks the buffer chunks for sz bytes and returns how many chunks are filled.
@@ -108,7 +114,7 @@ BOOL ringbuffer_commit_written_bytes(RingBuffer *rb, size_t sz);
  * @param sz the requested size
  * @return the number of chunks used for reading sz bytes
  */
-int ringbuffer_peek(const RingBuffer *rb, DataChunk chunks[2], size_t sz);
+FREERDP_API int ringbuffer_peek(const RingBuffer *rb, DataChunk chunks[2], size_t sz);
 
 /** move ahead the read head in case some byte were read using ringbuffer_peek()
  * This function is used to commit the bytes that were effectively consumed.
@@ -116,7 +122,11 @@ int ringbuffer_peek(const RingBuffer *rb, DataChunk chunks[2], size_t sz);
  * @param rb the ring buffer
  * @param sz the
  */
-void ringbuffer_commit_read_bytes(RingBuffer *rb, size_t sz);
+FREERDP_API void ringbuffer_commit_read_bytes(RingBuffer *rb, size_t sz);
 
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* __RINGBUFFER_H___ */
diff --git a/libfreerdp/core/tcp.c b/libfreerdp/core/tcp.c
index 6676382fc..ee9e5099f 100644
--- a/libfreerdp/core/tcp.c
+++ b/libfreerdp/core/tcp.c
@@ -85,7 +85,7 @@ static int transport_bio_buffered_write(BIO* bio, const char* buf, int num)
 	/* we directly append extra bytes in the xmit buffer, this could be prevented
 	 * but for now it makes the code more simple.
 	 */
-	if (buf && num && !ringbuffer_write(&tcp->xmitBuffer, buf, num))
+	if (buf && num && !ringbuffer_write(&tcp->xmitBuffer, (const BYTE *)buf, num))
 	{
 		fprintf(stderr, "%s: an error occured when writing(toWrite=%d)\n", __FUNCTION__, num);
 		return -1;