diff --git a/ndn-cpp/c/encoding/binary-xml-decoder.h b/ndn-cpp/c/encoding/binary-xml-decoder.h
index dfa9b97..a520a0f 100644
--- a/ndn-cpp/c/encoding/binary-xml-decoder.h
+++ b/ndn-cpp/c/encoding/binary-xml-decoder.h
@@ -16,11 +16,11 @@
 
 struct ndn_BinaryXmlDecoder {
   uint8_t *input;
-  unsigned int inputLength;
-  unsigned int offset;
+  size_t inputLength;
+  size_t offset;
 };
 
-static inline void ndn_BinaryXmlDecoder_initialize(struct ndn_BinaryXmlDecoder *self, uint8_t *input, unsigned int inputLength) 
+static inline void ndn_BinaryXmlDecoder_initialize(struct ndn_BinaryXmlDecoder *self, uint8_t *input, size_t inputLength) 
 {
   self->input = input;
   self->inputLength = inputLength;
@@ -78,7 +78,7 @@
  * and the binary data is absent
  */
 ndn_Error ndn_BinaryXmlDecoder_readBinaryDTagElement
-  (struct ndn_BinaryXmlDecoder *self, unsigned int expectedTag, int allowNull, uint8_t **value, unsigned int *valueLength);
+  (struct ndn_BinaryXmlDecoder *self, unsigned int expectedTag, int allowNull, uint8_t **value, size_t *valueLength);
 
 /**
  * Peek at the next element and if it is the expectedTag, call ndn_BinaryXmlDecoder_readBinaryDTagElement.
@@ -93,7 +93,7 @@
  * @return 0 for success, else an error code, including if allowNull is 0 and the binary data is absent
  */
 ndn_Error ndn_BinaryXmlDecoder_readOptionalBinaryDTagElement
-  (struct ndn_BinaryXmlDecoder *self, unsigned int expectedTag, int allowNull, uint8_t **value, unsigned int *valueLength);
+  (struct ndn_BinaryXmlDecoder *self, unsigned int expectedTag, int allowNull, uint8_t **value, size_t *valueLength);
 
 /**
  * Decode the header from self's input starting at offset, expecting the type to be DTAG and the value to be expectedTag.
@@ -106,7 +106,7 @@
  * @return 0 for success, else an error code, including an error if not the expected tag, or if the item is not UDATA.
  */
 ndn_Error ndn_BinaryXmlDecoder_readUDataDTagElement
-  (struct ndn_BinaryXmlDecoder *self, unsigned int expectedTag, uint8_t **value, unsigned int *valueLength);
+  (struct ndn_BinaryXmlDecoder *self, unsigned int expectedTag, uint8_t **value, size_t *valueLength);
 
 /**
  * Peek at the next element and if it is the expectedTag, call ndn_BinaryXmlDecoder_readUDataDTagElement.
@@ -120,7 +120,7 @@
  * @return 0 for success, else an error code.
  */
 ndn_Error ndn_BinaryXmlDecoder_readOptionalUDataDTagElement
-  (struct ndn_BinaryXmlDecoder *self, unsigned int expectedTag, uint8_t **value, unsigned int *valueLength);
+  (struct ndn_BinaryXmlDecoder *self, unsigned int expectedTag, uint8_t **value, size_t *valueLength);
 
 /**
  * Decode the header from self's input starting at offset, expecting the type to be DTAG and the value to be expectedTag.
@@ -177,14 +177,14 @@
  * @param bytesLength the length of bytes
  * @return the result
  */
-double ndn_BinaryXmlDecoder_unsignedBigEndianToDouble(uint8_t *bytes, unsigned int bytesLength); 
+double ndn_BinaryXmlDecoder_unsignedBigEndianToDouble(uint8_t *bytes, size_t bytesLength); 
 
 /**
  * Set the offset into the input, used for the next read.
  * @param self pointer to the ndn_BinaryXmlDecoder struct
  * @param offset the new offset
  */
-static inline void ndn_BinaryXmlDecoder_seek(struct ndn_BinaryXmlDecoder *self, unsigned int offset) 
+static inline void ndn_BinaryXmlDecoder_seek(struct ndn_BinaryXmlDecoder *self, size_t offset) 
 {
   self->offset = offset;
 }