Fix compiler warning

fixes #10956

diff --git a/lib/remote/base64.cpp b/lib/remote/base64.cpp
index f818b8bb7c9dc86a2d0629c803359f4a86100f7d..3f0a587d726f22ca35d0d66ae9a0f8212579abcc 100644 (file)
--- a/lib/remote/base64.cpp
+++ b/lib/remote/base64.cpp
@@ -53,8 +53,10 @@ String Base64::Decode(const String& input)
 
        char *outbuf = new char[input.GetLength()];
        
-       size_t rc, len = 0;
-       while (rc = BIO_read(bio64, outbuf + len, input.GetLength() - len))
+       size_t len = 0;
+       int rc;
+
+       while ((rc = BIO_read(bio64, outbuf + len, input.GetLength() - len)) > 0)
                len += rc;
 
        String ret = String(outbuf, outbuf + len);