diff --git a/c14n.c b/c14n.c
new file mode 100644
index 0000000..1db73fc
--- /dev/null
+++ b/c14n.c
@@ -0,0 +1,1556 @@
+/*
+ * "Canonical XML" implementation 
+ * http://www.w3.org/TR/xml-c14n
+ * 
+ * "Exclusive XML Canonicalization" implementation
+ * http://www.w3.org/TR/xml-exc-c14n
+ *
+ * See Copyright for the status of this software.
+ * 
+ * Author: Aleksey Sanin <aleksey@aleksey.com>
+ */
+#include "libxml.h"
+#ifdef LIBXML_C14N_ENABLED
+
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#include <string.h>
+
+#include <libxml/tree.h>
+#include <libxml/parser.h>
+#include <libxml/uri.h> 
+#include <libxml/xmlerror.h>
+#include <libxml/globals.h>
+#include <libxml/xpathInternals.h>
+#include <libxml/c14n.h>
+
+/************************************************************************
+ *									*
+ *		Some declaration better left private ATM		*
+ *									*
+ ************************************************************************/
+
+typedef enum {    
+    XMLC14N_BEFORE_DOCUMENT_ELEMENT=	0,
+    XMLC14N_INSIDE_DOCUMENT_ELEMENT=	1,
+    XMLC14N_AFTER_DOCUMENT_ELEMENT=	2    
+} xmlC14NPosition;
+
+typedef struct _xmlC14NCtx {
+    /* input parameters */
+    xmlDocPtr		doc;
+    xmlNodeSetPtr	visible_nodes;
+    int			with_comments;
+    xmlOutputBufferPtr	buf;
+
+    /* position in the XML document */
+    xmlC14NPosition	pos;
+    int			parent_is_doc;
+
+    /* exclusive canonicalization */
+    int			exclusive;
+    xmlNodeSetPtr	ns_rendered;
+    xmlChar		**inclusive_ns_prefixes;
+} xmlC14NCtx, *xmlC14NCtxPtr;
+
+
+static int	xmlC14NProcessNode	(xmlC14NCtxPtr ctx, 
+					 xmlNodePtr cur);
+static int	xmlC14NProcessNodeList	(xmlC14NCtxPtr ctx,
+					 xmlNodePtr cur);
+typedef enum {
+    XMLC14N_NORMALIZE_ATTR=		0,
+    XMLC14N_NORMALIZE_COMMENT=		1,
+    XMLC14N_NORMALIZE_PI=		2,
+    XMLC14N_NORMALIZE_TEXT=		3
+} xmlC14NNormalizationMode;    
+
+static xmlChar* xmlC11NNormalizeString	(const xmlChar *input,
+					 xmlC14NNormalizationMode mode);
+
+#define 	xmlC11NNormalizeAttr( a ) \
+    xmlC11NNormalizeString((a), XMLC14N_NORMALIZE_ATTR) 
+#define 	xmlC11NNormalizeComment( a ) \
+    xmlC11NNormalizeString((a), XMLC14N_NORMALIZE_COMMENT) 
+#define 	xmlC11NNormalizePI( a )	\
+    xmlC11NNormalizeString((a), XMLC14N_NORMALIZE_PI) 
+#define 	xmlC11NNormalizeText( a ) \
+    xmlC11NNormalizeString((a), XMLC14N_NORMALIZE_TEXT) 
+
+/************************************************************************
+ *									*
+ *		The implementation internals				*
+ *									*
+ ************************************************************************/
+
+/**
+ * xmlC14NIsVisible:
+ * @ctx: 		the C14N context
+ * @node: 		the node to check
+ *  		
+ * Checks whether the given node is visible. If the XML document normalization
+ * was called for the whole document then it is always "true".
+ *
+ * Returns 1 if the node is visible or 0 otherwise.  
+ */
+/* todo: make it a define? */
+static int 
+xmlC14NIsVisible(xmlC14NCtxPtr ctx, void *node) {
+    /* 
+     * If the input is an XPath node-set, then the node-set must explicitly 
+     * contain every node to be rendered to the canonical form.
+     */
+    if(ctx->visible_nodes != NULL && 
+	    !xmlXPathNodeSetContains(ctx->visible_nodes, (xmlNodePtr)node)) {
+	return(0);
+    }     
+
+    return(1);
+}
+
+/**
+ * xmlC14NIsXmlNs:
+ * @ns: 		the namespace to check
+ *  		
+ * Checks whether the given namespace is a default "xml:" namespace
+ * with href="http://www.w3.org/XML/1998/namespace"
+ *
+ * Returns 1 if the node is default or 0 otherwise
+ */
+/* todo: make it a define? */
+static int
+xmlC14NIsXmlNs(xmlNsPtr ns) {
+    return (ns != NULL && 
+	    xmlStrEqual(ns->prefix, BAD_CAST "xml") && 
+	    xmlStrEqual(ns->href, BAD_CAST "http://www.w3.org/XML/1998/namespace")); 
+}
+
+/**
+ * xmlExcC14NIsRendered:
+ * @ctx			the C14N context 
+ * @ns			the namespace to check
+ *
+ * Checks whether the given namespace was already rendered or not
+ *
+ * Returns 1 if we already wrote this namespace or 0 otherwise
+ */
+static int
+xmlExcC14NIsRendered(xmlC14NCtxPtr ctx, xmlNsPtr ns) {
+    int i;
+    
+    if(ctx == NULL || ctx->ns_rendered == NULL || ns == NULL) {
+	return(0);
+    }
+
+    if(ctx->ns_rendered->nodeTab != NULL) {
+        for(i = ctx->ns_rendered->nodeNr - 1; i >= 0; --i) {
+	    xmlNsPtr ns1 = (xmlNsPtr)ctx->ns_rendered->nodeTab[i];
+	    if(xmlStrEqual(ns1->prefix, ns->prefix)) {
+		return (xmlStrEqual(ns1->href, ns->href));
+	    }
+	}
+    }   
+    /*
+     * if the default namespace xmlns="" is not defined yet then 
+     * we do not want to print it out
+     */
+    return(xmlStrlen(ns->prefix) == 0 && xmlStrlen(ns->href) == 0); 
+}
+
+/**
+ * xmlC14NNamespacesCompare:
+ * @ns1:		the pointer to first namespace
+ * @ns2: 		the pointer to second namespace
+ *
+ * Compares the namespaces by names (prefixes).
+ *
+ * Returns -1 if ns1 < ns2, 0 if ns1 == ns2 or 1 if ns1 > ns2.
+ */
+static int 
+xmlC14NNamespacesCompare(xmlNsPtr ns1, xmlNsPtr ns2) {
+    if(ns1 == ns2) return(0);
+    if(ns1 == NULL) return(-1);
+    if(ns2 == NULL) return(1);
+    
+    return(xmlStrcmp(ns1->prefix, ns2->prefix));
+}
+
+
+/**
+ * xmlC14NPrintNamespaces:
+ * @ns:			the pointer to namespace
+ * @ctx: 		the C14N context
+ *
+ * Prints the given namespace to the output buffer from C14N context.
+ *
+ * Returns 1 on success or 0 on fail.
+ */
+static int
+xmlC14NPrintNamespaces(const xmlNsPtr ns, xmlC14NCtxPtr ctx) {
+
+    if(ns == NULL || ctx == NULL) {
+#ifdef DEBUG_C14N
+        xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NPrintNamespace: namespace or context pointer is null\n");
+#endif
+	return 0;
+    }
+
+    if(ns->prefix != NULL) {
+	xmlOutputBufferWriteString(ctx->buf, " xmlns:");
+	xmlOutputBufferWriteString(ctx->buf, (const char *)ns->prefix);
+	xmlOutputBufferWriteString(ctx->buf, "=\"");
+    } else {
+	xmlOutputBufferWriteString(ctx->buf, " xmlns=\"");
+    }
+    xmlOutputBufferWriteString(ctx->buf, (const char *) ns->href);
+    xmlOutputBufferWriteString(ctx->buf, "\"");
+    return(1);
+}
+
+/**
+ * xmlC14NProcessNamespacesAxis:
+ * @ctx: 		the C14N context
+ * @node:		the current node
+ *
+ * Prints out canonical namespace axis of the current node to the
+ * buffer from C14N context as follows 
+ *
+ * Canonical XML v 1.0 (http://www.w3.org/TR/xml-c14n)
+ *
+ * Namespace Axis
+ * Consider a list L containing only namespace nodes in the 
+ * axis and in the node-set in lexicographic order (ascending). To begin 
+ * processing L, if the first node is not the default namespace node (a node 
+ * with no namespace URI and no local name), then generate a space followed 
+ * by xmlns="" if and only if the following conditions are met:
+ *    - the element E that owns the axis is in the node-set
+ *    - The nearest ancestor element of E in the node-set has a default 
+ *	    namespace node in the node-set (default namespace nodes always 
+ *      have non-empty values in XPath)
+ * The latter condition eliminates unnecessary occurrences of xmlns="" in 
+ * the canonical form since an element only receives an xmlns="" if its 
+ * default namespace is empty and if it has an immediate parent in the 
+ * canonical form that has a non-empty default namespace. To finish 
+ * processing  L, simply process every namespace node in L, except omit 
+ * namespace node with local name xml, which defines the xml prefix, 
+ * if its string value is http://www.w3.org/XML/1998/namespace.
+ *
+ * Exclusive XML Canonicalization v 1.0 (http://www.w3.org/TR/xml-exc-c14n)
+ * Canonical XML applied to a document subset requires the search of the 
+ * ancestor nodes of each orphan element node for attributes in the xml 
+ * namespace, such as xml:lang and xml:space. These are copied into the 
+ * element node except if a declaration of the same attribute is already 
+ * in the attribute axis of the element (whether or not it is included in 
+ * the document subset). This search and copying are omitted from the 
+ * Exclusive XML Canonicalization method.
+ *
+ * Returns 0 on success or -1 on fail.
+ */
+static int
+xmlC14NProcessNamespacesAxis(xmlC14NCtxPtr ctx, xmlNodePtr cur) {
+    xmlNsPtr ns;
+    xmlListPtr list;
+    xmlNodePtr visible_parent;
+    xmlNsPtr prev;
+        
+    if(ctx == NULL || cur == NULL || cur->type != XML_ELEMENT_NODE) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NProcessNamespacesAxis: Null context or node pointer or type != XML_ELEMENT_NODE.\n");
+#endif	
+        return(-1);
+    }    
+
+    /*
+     * Create a sorted list to store element namespaces
+     */
+    list = xmlListCreate(NULL, (xmlListDataCompare)xmlC14NNamespacesCompare);
+    if(list == NULL) {
+#ifdef DEBUG_C14N
+        xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NProcessNamespacesAxis: list creation failed\n");
+#endif
+	return(-1);
+    }    
+    
+    /* find nearest visible parent */
+    visible_parent = cur->parent;
+    while(visible_parent != NULL && !xmlC14NIsVisible(ctx, visible_parent)) {
+	visible_parent = visible_parent->parent;  
+    }
+
+    /* 
+     * todo: the libxml XPath implementation does not create 
+     * nodes for all namespaces known to the node (i.e. for namespaces
+     * defined in node parents). By this we need to now walk thru 
+     * all namespace in current node and all invisible ancesstors
+     */
+     while(cur != visible_parent) {
+        for(ns = cur->nsDef; ns != NULL; ns = ns->next) { 
+    	    /* 
+	     * first of all ignore default "xml" namespace and 
+	     * already included namespace
+	     */
+	    if(xmlC14NIsXmlNs(ns) || xmlListSearch(list, ns) != NULL) {
+	        continue;
+	    } 
+
+	    /*
+	     * Lookup nearest namespace after visible parent having
+	     * the same prefix. Namespace included if and only if one of 
+	     * the following:
+	     *   - another namespace having the same prefix but 
+	     *   different value found or
+	     *   - there is no namespaces having the same prefix and  
+	     *   it is not a default xmlns="" namespace (empty prefix 
+	     *   and empty href)
+	     */
+	    prev = xmlSearchNs(ctx->doc, visible_parent, ns->prefix);
+	    if(prev == NULL && (xmlStrlen(ns->prefix) > 0 || xmlStrlen(ns->href) > 0)) {
+		xmlListInsert(list, ns);
+	    } else if(prev != NULL && !xmlStrEqual(ns->href, prev->href)) {
+	        xmlListInsert(list, ns);
+	    }
+	}
+	cur = cur->parent;
+    }
+
+    /* 
+     * print out all elements from list 
+     */
+    xmlListWalk(list, (xmlListWalker)xmlC14NPrintNamespaces, (const void*)ctx);
+    
+    /* 
+     * Cleanup
+     */
+    xmlListDelete(list);
+    return(0);
+}
+
+/**
+ * xmlExcC14NProcessNamespacesAxis:
+ * @ctx: 		the C14N context
+ * @node:		the current node
+ *
+ * Prints out exclusive canonical namespace axis of the current node to the
+ * buffer from C14N context as follows 
+ *
+ * Exclusive XML Canonicalization
+ * http://www.w3.org/TR/xml-exc-c14n
+ *
+ * If the element node is in the XPath subset then output the node in 
+ * accordance with Canonical XML except for namespace nodes which are 
+ * rendered as follows:
+ *
+ * 1. Render each namespace node iff:
+ *    * it is visibly utilized by the immediate parent element or one of 
+ *      its attributes, or is present in InclusiveNamespaces PrefixList, and
+ *    * its prefix and value do not appear in ns_rendered. ns_rendered is 
+ *      obtained by popping the state stack in order to obtain a list of 
+ *      prefixes and their values which have already been rendered by 
+ *      an output ancestor of the namespace node's parent element.
+ * 2. Append the rendered namespace node to the list ns_rendered of namespace 
+ * nodes rendered by output ancestors. Push ns_rendered on state stack and 
+ * recurse.
+ * 3. After the recursion returns, pop thestate stack.
+ *
+ *
+ * Returns 0 on success or -1 on fail.
+ */
+static int
+xmlExcC14NProcessNamespacesAxis(xmlC14NCtxPtr ctx, xmlNodePtr cur) {
+    xmlListPtr list;
+    xmlAttrPtr attr;
+    xmlNsPtr ns;
+            
+    if(ctx == NULL || cur == NULL || cur->type != XML_ELEMENT_NODE) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlExcC14NProcessNamespacesAxis: Null context or node pointer or type != XML_ELEMENT_NODE.\n");
+#endif	
+        return(-1);
+    }    
+    
+    if(!ctx->exclusive || ctx->ns_rendered == NULL) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlExcC14NProcessNamespacesAxis: called for non-exclusive canonization or rendered stack is NULL.\n");
+#endif	
+        return(-1);
+	
+    }
+    
+    /*
+     * Create a sorted list to store element namespaces
+     */
+    list = xmlListCreate(NULL, (xmlListDataCompare)xmlC14NNamespacesCompare);
+    if(list == NULL) {
+#ifdef DEBUG_C14N
+        xmlGenericError(xmlGenericErrorContext,
+		"xmlExcC14NProcessNamespacesAxis: list creation failed\n");
+#endif
+	return(-1);
+    }    
+
+    /*
+     * First of all, add all namespaces required by current node
+     * (i.e. node namespace and all attribute namespaces)
+     * todo: do we need to check for default "xml:" namespace
+     */
+    ns = (cur->ns != NULL) ? cur->ns : xmlSearchNs(ctx->doc, cur, NULL);
+    if(ns != NULL && !xmlC14NIsXmlNs(ns) && xmlListSearch(list, ns) == NULL) {
+	if(!xmlExcC14NIsRendered(ctx, ns)) {
+		xmlListInsert(list, ns);
+		xmlXPathNodeSetAdd(ctx->ns_rendered, (xmlNodePtr)ns);
+	}
+    }
+    attr = cur->properties;
+    while (attr != NULL) { 
+	/* 
+	 * todo: do we need to check that attribute is visible and has non
+	 * default namespace
+	 */
+	if(xmlC14NIsVisible(ctx, attr)) {
+	    ns = (attr->ns != NULL) ? attr->ns : xmlSearchNs(ctx->doc, cur, NULL);
+	    if(ns != NULL && xmlC14NIsVisible(ctx, attr) && !xmlC14NIsXmlNs(ns)) {
+		if(xmlListSearch(list, ns) == NULL && 
+		    !xmlExcC14NIsRendered(ctx, ns)) {
+			xmlListInsert(list, ns);
+			xmlXPathNodeSetAdd(ctx->ns_rendered, (xmlNodePtr)ns);
+		}
+	    }
+	}
+	attr = attr->next;
+    }
+        
+    /* 
+     * Next add all inclusive namespaces if needed. 
+     */
+    if(ctx->inclusive_ns_prefixes != NULL) {
+	int i;
+	xmlChar *prefix;
+	
+	for(i = 0; ctx->inclusive_ns_prefixes[i] != NULL; ++i) {
+	    prefix = ctx->inclusive_ns_prefixes[i];
+	    /*
+	     * Special values for namespace with empty prefix
+	     */    
+	    if(xmlStrEqual(prefix, BAD_CAST "#default") || xmlStrEqual(prefix, BAD_CAST "")) {
+		prefix = NULL;
+	    }
+	    ns = xmlSearchNs(ctx->doc, cur, prefix);
+	    if(ns != NULL && !xmlC14NIsXmlNs(ns)) {
+		if(xmlListSearch(list, ns) == NULL && 
+		    !xmlExcC14NIsRendered(ctx, ns)) {
+			xmlListInsert(list, ns);
+			xmlXPathNodeSetAdd(ctx->ns_rendered, (xmlNodePtr)ns);
+		}
+	    }	    
+	}	
+    }
+        
+    /* 
+     * print out all elements from list 
+     */
+    xmlListWalk(list, (xmlListWalker)xmlC14NPrintNamespaces, (const void*)ctx);
+    
+    /* 
+     * Cleanup
+     */
+    xmlListDelete(list);
+    return(0);
+}
+
+
+/**
+ * xmlC14NAttrsCompare:
+ * @attr1:		the pointer to first attr
+ * @attr2: 		the pointer to second attr
+ *
+ * Prints the given attribute to the output buffer from C14N context.
+ *
+ * Returns -1 if attr1 < attr2, 0 if attr1 == attr2 or 1 if attr1 > attr2.
+ */
+static int
+xmlC14NAttrsCompare(xmlAttrPtr attr1, xmlAttrPtr attr2) {
+    int ret = 0;
+
+    /*
+     * Simple cases
+     */
+    if(attr1 == attr2) return(0);
+    if(attr1 == NULL) return(-1);
+    if(attr2 == NULL) return(1);
+    if(attr1->ns == attr2->ns) {
+	return(xmlStrcmp(attr1->name, attr2->name));        
+    }
+
+    /* 
+     * Attributes in the default namespace are first
+     * because the default namespace is not applied to
+     * unqualified attributes
+     */
+    if(attr1->ns == NULL) return(-1);
+    if(attr2->ns == NULL) return(1);
+    if(attr1->ns->prefix == NULL) return(-1);
+    if(attr2->ns->prefix == NULL) return(1);
+    
+    ret = xmlStrcmp(attr1->ns->href, attr2->ns->href);
+    if(ret == 0) {
+	ret = xmlStrcmp(attr1->name, attr2->name);
+    }
+    return(ret);
+}
+
+
+/**
+ * xmlC14NPrintAttrs:
+ * @attr:		the pointer to attr
+ * @ctx: 		the C14N context
+ *
+ * Prints out canonical attribute urrent node to the
+ * buffer from C14N context as follows 
+ *
+ * Canonical XML v 1.0 (http://www.w3.org/TR/xml-c14n)
+ *
+ * Returns 1 on success or 0 on fail.
+ */
+static int
+xmlC14NPrintAttrs(const xmlAttrPtr attr, xmlC14NCtxPtr ctx) {
+    xmlChar *value;
+    xmlChar *buffer;
+
+    if(attr == NULL || ctx == NULL) {
+#ifdef DEBUG_C14N
+        xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NPrintAttrs: attr == NULL or ctx == NULL\n");
+#endif
+	return(0);
+    }
+
+    xmlOutputBufferWriteString(ctx->buf, " ");
+    if(attr->ns != NULL && xmlStrlen(attr->ns->prefix) > 0) {
+        xmlOutputBufferWriteString(ctx->buf, (const char *) attr->ns->prefix);
+        xmlOutputBufferWriteString(ctx->buf, ":");   
+    }
+    xmlOutputBufferWriteString(ctx->buf, (const char *) attr->name);
+    xmlOutputBufferWriteString(ctx->buf, "=\"");
+
+    value = xmlNodeListGetString(attr->doc, attr->children, 1);
+    /* todo: should we log an error if value==NULL ? */
+    if(value != NULL) {
+	buffer = xmlC11NNormalizeAttr(value);
+	xmlFree(value);
+	if (buffer != NULL) {
+    	    xmlOutputBufferWriteString(ctx->buf, (const char *)buffer);
+    	    xmlFree(buffer);
+	} else {
+#ifdef DEBUG_C14N
+	    xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NPrintAttrs: xmlC11NNormalizeAttr failed\n");
+#endif
+	    return(0);
+	}
+    }
+    xmlOutputBufferWriteString(ctx->buf, "\"");
+    return(1);
+}
+
+/**
+ * xmlC14NProcessAttrsAxis:
+ * @ctx: 		the C14N context
+ * @cur:		the current node
+ *
+ * Prints out canonical attribute axis of the current node to the
+ * buffer from C14N context as follows 
+ *
+ * Canonical XML v 1.0 (http://www.w3.org/TR/xml-c14n)
+ *
+ * Attribute Axis 
+ * In lexicographic order (ascending), process each node that 
+ * is in the element's attribute axis and in the node-set.
+ * 
+ * The processing of an element node E MUST be modified slightly 
+ * when an XPath node-set is given as input and the element's 
+ * parent is omitted from the node-set.
+ *
+ *
+ * Exclusive XML Canonicalization v 1.0 (http://www.w3.org/TR/xml-exc-c14n)
+ *
+ * Canonical XML applied to a document subset requires the search of the 
+ * ancestor nodes of each orphan element node for attributes in the xml 
+ * namespace, such as xml:lang and xml:space. These are copied into the 
+ * element node except if a declaration of the same attribute is already 
+ * in the attribute axis of the element (whether or not it is included in 
+ * the document subset). This search and copying are omitted from the 
+ * Exclusive XML Canonicalization method.
+ *
+ * Returns 0 on success or -1 on fail.
+ */
+static int
+xmlC14NProcessAttrsAxis(xmlC14NCtxPtr ctx, xmlNodePtr cur) {
+    xmlAttrPtr attr;
+    xmlListPtr list;
+    
+    if(ctx == NULL || cur == NULL || cur->type != XML_ELEMENT_NODE) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NProcessAttrsAxis: Null context or node pointer or type != XML_ELEMENT_NODE.\n");
+#endif	
+        return(-1);
+    }    
+
+    /*
+     * Create a sorted list to store element attributes
+     */
+    list = xmlListCreate(NULL, (xmlListDataCompare)xmlC14NAttrsCompare);
+    if(list == NULL) {
+#ifdef DEBUG_C14N
+        xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NProcessAttrsAxis: list creation failed\n");
+#endif
+	return(-1);
+    }
+
+    /* 
+     * Add all visible attributes from current node. 
+     */
+    attr = cur->properties;
+    while (attr != NULL) { 
+	/* check that attribute is visible */
+	if(xmlC14NIsVisible(ctx, attr)) {
+	    xmlListInsert(list, attr);
+	}
+	attr = attr->next;
+    }
+    
+    /* 
+     * include attributes in "xml" namespace defined in ancestors
+     * (only for non-exclusive XML Canonicalization)
+     */
+    if(!ctx->exclusive && cur->parent != NULL && !xmlC14NIsVisible(ctx, cur->parent)) {    
+        /*
+	 * If XPath node-set is not specified then the parent is always 
+	 * visible!
+	 */
+	 cur = cur->parent;
+	 while(cur != NULL) {
+	    attr = cur->properties;
+	    while (attr != NULL) { 
+		if(attr->ns != NULL && xmlStrEqual(attr->ns->prefix, BAD_CAST "xml")) {
+		    if(xmlListSearch(list, attr) == NULL) {
+			xmlListInsert(list, attr);
+		    }
+		}
+		attr = attr->next;
+	    }
+	    cur = cur->parent;
+	 }
+    }
+    
+    /* 
+     * print out all elements from list 
+     */
+    xmlListWalk(list, (xmlListWalker)xmlC14NPrintAttrs, (const void*)ctx);
+    
+    /* 
+     * Cleanup
+     */
+    xmlListDelete(list);    
+    return(0);
+}
+
+/** 
+ * xmlC14NCheckForRelativeNamespaces:
+ * @ctx:		the C14N context
+ * @cur:		the current element node
+ *
+ * Checks that current element node has no relative namespaces defined
+ *
+ * Returns 0 if the node has no relative namespaces or -1 otherwise.
+ */
+static int
+xmlC14NCheckForRelativeNamespaces(xmlC14NCtxPtr ctx, xmlNodePtr cur) {
+    xmlNsPtr ns;
+        
+    if(ctx == NULL || cur == NULL || cur->type != XML_ELEMENT_NODE) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NCheckForRelativeNamespaces: Null context or node pointer or type != XML_ELEMENT_NODE.\n");
+#endif	
+        return(-1);
+    }    
+
+    ns = cur->nsDef; 
+    while(ns != NULL) {
+	if(xmlStrlen(ns->href) > 0) {
+	    xmlURIPtr uri;
+	    
+	    uri = xmlParseURI((const char *) ns->href);
+	    if(uri == NULL) {
+#ifdef DEBUG_C14N    
+    		xmlGenericError(xmlGenericErrorContext,
+        	    "xmlC14NCheckForRelativeNamespaces: unable to parse uri=\"%s\".\n", ns->href);
+#endif		
+		return(-1);
+	    }
+	    if(xmlStrlen((const xmlChar *) uri->scheme) == 0) {
+		xmlFreeURI(uri); 
+		return(-1);
+	    }
+	    if(!xmlStrEqual((const xmlChar *) uri->scheme, BAD_CAST "urn") && xmlStrlen((const xmlChar *) uri->server) == 0) {
+		xmlFreeURI(uri); 
+		return(-1);
+	    }
+	    xmlFreeURI(uri);   
+	}
+	ns = ns->next;
+    }
+    return(0);
+}
+
+/**
+ * xmlC14NProcessElementNode:
+ * @ctx: 		the pointer to C14N context object
+ * @cur:		the node to process
+ *  		
+ * Canonical XML v 1.0 (http://www.w3.org/TR/xml-c14n)
+ *
+ * Element Nodes
+ * If the element is not in the node-set, then the result is obtained 
+ * by processing the namespace axis, then the attribute axis, then 
+ * processing the child nodes of the element that are in the node-set 
+ * (in document order). If the element is in the node-set, then the result 
+ * is an open angle bracket (<), the element QName, the result of 
+ * processing the namespace axis, the result of processing the attribute 
+ * axis, a close angle bracket (>), the result of processing the child 
+ * nodes of the element that are in the node-set (in document order), an 
+ * open angle bracket, a forward slash (/), the element QName, and a close 
+ * angle bracket.
+ *
+ * Returns non-negative value on success or negative value on fail
+ */
+static int
+xmlC14NProcessElementNode(xmlC14NCtxPtr ctx, xmlNodePtr cur, int visible) {
+    int ret;
+    int ns_rendered_pos = 0;
+
+    if(ctx == NULL || cur == NULL || cur->type != XML_ELEMENT_NODE) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NProcessElementNode: Null context or node pointer or type != XML_ELEMENT_NODE.\n");
+#endif	
+        return(-1);
+    }    
+
+    /* 
+     * Check relative relative namespaces:
+     * implementations of XML canonicalization MUST report an operation
+     * failure on documents containing relative namespace URIs.
+     */
+    if(xmlC14NCheckForRelativeNamespaces(ctx, cur) < 0) {
+#ifdef DEBUG_C14N    
+    	xmlGenericError(xmlGenericErrorContext,
+    	    "xmlC14NProcessElementNode: xmlC14NCheckForRelativeNamespaces failed.\n");
+#endif	
+    	return(-1);
+    }
+
+
+    /* 
+     * Save ns_rendered stack position for exclusive 
+     * processing
+     */
+    if(ctx->exclusive && ctx->ns_rendered != NULL) {
+	ns_rendered_pos = ctx->ns_rendered->nodeNr;
+    } 
+
+    if(visible) {
+	if(ctx->parent_is_doc) {
+	    ctx->pos = XMLC14N_INSIDE_DOCUMENT_ELEMENT;
+	} 
+	xmlOutputBufferWriteString(ctx->buf, "<");
+
+	if(cur->ns != NULL && xmlStrlen(cur->ns->prefix) > 0) {
+	    xmlOutputBufferWriteString(ctx->buf, (const char *)cur->ns->prefix);
+	    xmlOutputBufferWriteString(ctx->buf, ":");
+	}
+	xmlOutputBufferWriteString(ctx->buf, (const char *)cur->name);
+
+	if(ctx->exclusive) {
+	    ret = xmlExcC14NProcessNamespacesAxis(ctx, cur);
+	} else {
+	    ret = xmlC14NProcessNamespacesAxis(ctx, cur);
+	}
+	if(ret < 0) {
+#ifdef DEBUG_C14N    
+    	    xmlGenericError(xmlGenericErrorContext,
+        	"xmlC14NProcessElementNode: xmlC14NProcessNamespacesAxis failed.\n");
+#endif	
+    	    return(-1);
+	}
+	
+	ret = xmlC14NProcessAttrsAxis(ctx, cur);
+	if(ret < 0) {
+#ifdef DEBUG_C14N    
+    	    xmlGenericError(xmlGenericErrorContext,
+        	"xmlC14NProcessElementNode: xmlC14NProcessAttrsAxis failed.\n");
+#endif	
+    	    return(-1);
+	}
+
+	xmlOutputBufferWriteString(ctx->buf, ">"); 
+    }
+    if (cur->children != NULL) {
+	ret = xmlC14NProcessNodeList(ctx, cur->children);
+	if(ret < 0) {
+#ifdef DEBUG_C14N    
+	    xmlGenericError(xmlGenericErrorContext,
+    		"xmlC14NProcessElementNode: xmlC14NProcessNodeList failed.\n");
+#endif	
+    	    return(-1);
+	}
+    }
+    if(visible) {
+	xmlOutputBufferWriteString(ctx->buf, "</");
+	if(cur->ns != NULL && xmlStrlen(cur->ns->prefix) > 0) {
+	    xmlOutputBufferWriteString(ctx->buf, (const char *)cur->ns->prefix);
+	    xmlOutputBufferWriteString(ctx->buf, ":");
+	}
+	xmlOutputBufferWriteString(ctx->buf, (const char *)cur->name);
+	xmlOutputBufferWriteString(ctx->buf, ">"); 
+	if(ctx->parent_is_doc) { 
+	    ctx->pos = XMLC14N_AFTER_DOCUMENT_ELEMENT; 
+	}
+    }
+
+    /* 
+     * Restore ns_rendered stack position for exclusive 
+     * processing
+     */
+    if(ctx->exclusive && ctx->ns_rendered != NULL) {
+	ctx->ns_rendered->nodeNr = ns_rendered_pos;
+    } 
+    return(0);
+}
+
+/**
+ * xmlC14NProcessNode:
+ * @ctx: 		the pointer to C14N context object
+ * @cur:		the node to process
+ *  		
+ * Processes the given node
+ *
+ * Returns non-negative value on success or negative value on fail
+ */
+static int
+xmlC14NProcessNode(xmlC14NCtxPtr ctx, xmlNodePtr cur) {
+    int ret = 0;
+    int visible;
+    
+    if(ctx == NULL || cur == NULL) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NProcessNode: Null context or node pointer.\n");
+#endif	
+        return(-1);
+    }
+
+    visible = xmlC14NIsVisible(ctx, cur);
+    switch(cur->type) {
+	case XML_ELEMENT_NODE:
+	    ret = xmlC14NProcessElementNode(ctx, cur, visible);
+	    break;  
+	case XML_CDATA_SECTION_NODE:
+	case XML_TEXT_NODE:
+	    /*
+	     * Text Nodes
+	     * the string value, except all ampersands are replaced 
+	     * by &amp;, all open angle brackets (<) are replaced by &lt;, all closing 
+	     * angle brackets (>) are replaced by &gt;, and all #xD characters are 
+	     * replaced by &#xD;.
+	     */
+	     /* cdata sections are processed as text nodes */
+	     /* todo: verify that cdata sections are included in XPath nodes set */ 
+	    if(visible && cur->content != NULL) {
+		xmlChar *buffer;
+
+#ifndef XML_USE_BUFFER_CONTENT
+		buffer = xmlC11NNormalizeText(cur->content);
+#else
+		buffer = xmlC11NNormalizeText(xmlBufferContent(cur->content));
+#endif
+		if(buffer != NULL) {
+		    xmlOutputBufferWriteString(ctx->buf, (const char *)buffer);
+		    xmlFree(buffer);
+		} else {
+#ifdef DEBUG_C14N
+    		    xmlGenericError(xmlGenericErrorContext,
+			"xmlC14NProcessNode: xmlC11NNormalizeText() failed\n");
+#endif
+		    return(-1);
+		}
+	    }
+	    break;
+	case XML_PI_NODE:
+	    /* 
+	     * Processing Instruction (PI) Nodes- 
+	     * The opening PI symbol (<?), the PI target name of the node, 
+	     * a leading space and the string value if it is not empty, and 
+	     * the closing PI symbol (?>). If the string value is empty, 
+	     * then the leading space is not added. Also, a trailing #xA is 
+	     * rendered after the closing PI symbol for PI children of the 
+	     * root node with a lesser document order than the document 
+	     * element, and a leading #xA is rendered before the opening PI 
+	     * symbol of PI children of the root node with a greater document 
+	     * order than the document element.
+	     */	    
+	    if(visible) {
+		if(ctx->pos == XMLC14N_AFTER_DOCUMENT_ELEMENT) {
+		    xmlOutputBufferWriteString(ctx->buf, "\x0A<?");
+		} else {
+		    xmlOutputBufferWriteString(ctx->buf, "<?");
+		}
+
+		xmlOutputBufferWriteString(ctx->buf, (const char *)cur->name);
+		if(cur->content != NULL && *(cur->content) != '\0') {
+		    xmlChar *buffer;
+		    xmlOutputBufferWriteString(ctx->buf, " ");
+		    
+		    /* todo: do we need to normalize pi? */
+#ifndef XML_USE_BUFFER_CONTENT
+		    buffer = xmlC11NNormalizePI(cur->content);
+#else
+		    buffer = xmlC11NNormalizePI(xmlBufferContent(cur->content));
+#endif
+		    if (buffer != NULL) {
+			xmlOutputBufferWriteString(ctx->buf, (const char *)buffer);
+			xmlFree(buffer);
+		    } else {
+#ifdef DEBUG_C14N
+    			xmlGenericError(xmlGenericErrorContext,
+			    "xmlC14NProcessNode: xmlC11NNormalizePI() failed\n");
+#endif
+			return(-1);
+		    }
+		}
+
+		if(ctx->pos == XMLC14N_BEFORE_DOCUMENT_ELEMENT) {
+    		    xmlOutputBufferWriteString(ctx->buf, "?>\x0A");
+		} else {
+    		    xmlOutputBufferWriteString(ctx->buf, "?>");
+		}
+	    }
+	    break;
+	case XML_COMMENT_NODE:
+	    /*
+	     * Comment Nodes
+	     * Nothing if generating canonical XML without  comments. For 
+	     * canonical XML with comments, generate the opening comment 
+	     * symbol (<!--), the string value of the node, and the 
+	     * closing comment symbol (-->). Also, a trailing #xA is rendered 
+	     * after the closing comment symbol for comment children of the 
+	     * root node with a lesser document order than the document 
+	     * element, and a leading #xA is rendered before the opening 
+	     * comment symbol of comment children of the root node with a 
+	     * greater document order than the document element. (Comment 
+	     * children of the root node represent comments outside of the 
+	     * top-level document element and outside of the document type 
+	     * declaration).
+	     */
+	    if(visible && ctx->with_comments) {		
+		if(ctx->pos == XMLC14N_AFTER_DOCUMENT_ELEMENT) {
+		    xmlOutputBufferWriteString(ctx->buf, "\x0A<!--");
+		} else {
+		    xmlOutputBufferWriteString(ctx->buf, "<!--");
+		}
+
+		if(cur->content != NULL) {
+		    xmlChar *buffer;
+
+		    /* todo: do we need to normalize comment? */
+#ifndef XML_USE_BUFFER_CONTENT
+		    buffer = xmlC11NNormalizeComment(cur->content);
+#else
+		    buffer = xmlC11NNormalizeString(xmlBufferContent(cur->content));
+#endif
+		    if (buffer != NULL) {
+			xmlOutputBufferWriteString(ctx->buf, (const char *)buffer);
+			xmlFree(buffer);
+		    } else {
+#ifdef DEBUG_C14N
+    			xmlGenericError(xmlGenericErrorContext,
+			    "xmlC14NProcessNode: xmlC11NNormalizeComment() failed\n");
+#endif
+			return(-1);
+		    }
+		}
+		
+		if(ctx->pos == XMLC14N_BEFORE_DOCUMENT_ELEMENT) {
+    		    xmlOutputBufferWriteString(ctx->buf, "-->\x0A");
+		} else {
+    		    xmlOutputBufferWriteString(ctx->buf, "-->");
+		}
+	    }
+	    break;
+	case XML_DOCUMENT_NODE:
+	case XML_DOCUMENT_FRAG_NODE: /* should be processed as document? */
+	case XML_DOCB_DOCUMENT_NODE: /* should be processed as document? */
+	case XML_HTML_DOCUMENT_NODE: /* should be processed as document? */
+	    if (cur->children != NULL) {
+		ctx->pos = XMLC14N_BEFORE_DOCUMENT_ELEMENT;
+		ctx->parent_is_doc = 1;
+		ret = xmlC14NProcessNodeList(ctx, cur->children);
+	    }
+	    break;
+
+	case XML_ATTRIBUTE_NODE:
+    	    xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NProcessNode: XML_ATTRIBUTE_NODE is illegal here\n");
+	    return(-1);
+	case XML_NAMESPACE_DECL:
+    	    xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NProcessNode: XML_NAMESPACE_DECL is illegal here\n");
+	    return(-1);
+	case XML_ENTITY_REF_NODE:
+    	    xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NProcessNode: XML_ENTITY_REF_NODE is illegal here\n");
+	    return(-1);
+	case XML_ENTITY_NODE: 
+    	    xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NProcessNode: XML_ENTITY_NODE is illegal here\n");
+	    return(-1);
+
+	case XML_DOCUMENT_TYPE_NODE:
+	case XML_NOTATION_NODE:
+	case XML_DTD_NODE:
+	case XML_ELEMENT_DECL:
+	case XML_ATTRIBUTE_DECL:
+	case XML_ENTITY_DECL:
+	case XML_XINCLUDE_START:
+	case XML_XINCLUDE_END:
+	    /* 
+	     * should be ignored according to "W3C Canonical XML" 
+	     */
+	    break;
+	default:
+#ifdef DEBUG_C14N
+    	    xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NProcessNode: unknown node type = %d\n", cur->type);
+#endif
+	    return(-1);
+    }
+
+    return(ret);
+}
+
+/**
+ * xmlC14NProcessNodeList:
+ * @ctx: 		the pointer to C14N context object
+ * @cur:		the node to start from
+ *  		
+ * Processes all nodes in the row starting from cur.
+ *
+ * Returns non-negative value on success or negative value on fail
+ */
+static int
+xmlC14NProcessNodeList(xmlC14NCtxPtr ctx, xmlNodePtr cur) {
+    int ret;
+    
+    if(ctx == NULL) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NProcessNodeList: Null context pointer.\n");
+#endif	
+        return(-1);
+    }
+
+    for(ret = 0; cur != NULL && ret >= 0; cur = cur->next) {
+	ret = xmlC14NProcessNode(ctx, cur);
+    }        
+    return(ret);
+}
+
+
+/**
+ * xmlC14NFreeCtx:
+ * @ctx: the pointer to C14N context object
+ * 		
+ * Cleanups the C14N context object.
+ */
+
+static void
+xmlC14NFreeCtx(xmlC14NCtxPtr ctx) {
+    if(ctx == NULL) {
+#ifdef DEBUG_C14N
+        xmlGenericError(xmlGenericErrorContext,
+		"xmlC14NFreeCtx: ctx == NULL\n");
+#endif
+	return;
+    }
+    
+    if(ctx->ns_rendered != NULL) {
+	xmlXPathFreeNodeSet(ctx->ns_rendered);
+    }
+    xmlFree(ctx);
+}
+
+/**
+ * xmlC14NNewCtx:
+ * @doc: 		the XML document for canonization
+ * @nodes: 		the nodes set to be included in the canonized image
+ *      		or NULL if all document nodes should be included
+ * @exclusive:		the exclusive flag (0 - non-exclusive canonicalization;
+ *			otherwise - exclusive canonicalization)
+ * @inclusive_ns_prefixe the list of inclusive namespace prefixes 
+ *			ended with a NULL or NULL if there is no
+ *			inclusive namespaces (only for exclusive 
+ *			canonicalization)
+ * @with_comments: 	include comments in the result (!=0) or not (==0)
+ * @buf: 		the output buffer to store canonical XML; this 
+ *			buffer MUST have encoder==NULL because C14N requires
+ *			UTF-8 output
+ *  		
+ * Creates new C14N context object to store C14N parameters.
+ *
+ * Returns pointer to newly created object (success) or NULL (fail)
+ */
+static xmlC14NCtxPtr
+xmlC14NNewCtx(xmlDocPtr doc, xmlNodeSetPtr nodes, 
+		int exclusive, xmlChar **inclusive_ns_prefixes,
+		int with_comments, 
+		xmlOutputBufferPtr buf) {
+    xmlC14NCtxPtr ctx;
+
+    if(doc == NULL || buf == NULL) {
+#ifdef DEBUG_C14N
+        xmlGenericError(xmlGenericErrorContext,
+	    "xmlC14NNewCtx: pointer to document or output buffer is NULL\n");
+#endif
+	return(NULL);
+    }
+
+    /*
+     *  Validate the encoding output buffer encoding
+     */
+    if(buf->encoder != NULL) {
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NNewCtx: output buffer encoder != NULL but C14N requires UTF8 output\n");
+        return(NULL);
+    }
+
+    /*
+     *  Validate the XML document encoding value, if provided.
+     */
+    if(doc->charset != XML_CHAR_ENCODING_UTF8) {
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NNewCtx: source document not in UTF8\n");
+        return(NULL);
+    } 
+
+    /*
+     * Allocate a new xmlC14NCtxPtr and fill the fields.
+     */
+    ctx = (xmlC14NCtxPtr) xmlMalloc(sizeof(xmlC14NCtx));
+    if (ctx == NULL) {
+        xmlGenericError(xmlGenericErrorContext,
+	    "xmlC14NNewCtx: malloc failed\n");
+	return(NULL);
+    }
+    memset(ctx, 0, sizeof(xmlC14NCtx));
+
+    /*
+     * initialize C14N context
+     */    
+    ctx->doc = doc;
+    ctx->with_comments = with_comments;
+    ctx->visible_nodes = nodes;
+    ctx->buf = buf;
+    ctx->parent_is_doc = 1;
+    ctx->pos = XMLC14N_BEFORE_DOCUMENT_ELEMENT;
+
+    /*
+     * Set "exclusive" flag, create a nodes set for namespaces
+     * stack and remember list of incluseve prefixes
+     */
+    if(exclusive) {
+	ctx->exclusive = 1;
+	ctx->ns_rendered = xmlXPathNodeSetCreate(NULL);
+        ctx->inclusive_ns_prefixes = inclusive_ns_prefixes;
+    }
+    return(ctx);
+}
+
+/**
+ * xmlC14NDocSaveTo:
+ * @doc: 		the XML document for canonization
+ * @nodes: 		the nodes set to be included in the canonized image
+ *      		or NULL if all document nodes should be included
+ * @exclusive:		the exclusive flag (0 - non-exclusive canonicalization;
+ *			otherwise - exclusive canonicalization)
+ * @inclusive_ns_prefixe the list of inclusive namespace prefixes 
+ *			ended with a NULL or NULL if there is no
+ *			inclusive namespaces (only for exclusive 
+ *			canonicalization, ignored otherwise)
+ * @with_comments: 	include comments in the result (!=0) or not (==0)
+ * @buf: 		the output buffer to store canonical XML; this 
+ *			buffer MUST have encoder==NULL because C14N requires
+ *			UTF-8 output
+ *  		
+ * Dumps the canonized image of given XML document into the provided buffer.
+ * For details see "Canonical XML" (http://www.w3.org/TR/xml-c14n) or
+ * "Exclusive XML Canonicalization" (http://www.w3.org/TR/xml-exc-c14n)
+ *
+ * Returns non-negative value on success or a negative value on fail  
+ */
+int
+xmlC14NDocSaveTo(xmlDocPtr doc, xmlNodeSetPtr nodes, 
+		int exclusive, xmlChar **inclusive_ns_prefixes,
+		int with_comments, 
+		xmlOutputBufferPtr buf) {
+    xmlC14NCtxPtr ctx;
+    int ret;
+    
+    if(buf == NULL || doc == NULL) {
+#ifdef DEBUG_C14N 	
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NDocSaveTo: null return buffer or doc pointer\n");
+#endif 	    
+        return(-1);
+    }
+
+    /*
+     *  Validate the encoding output buffer encoding
+     */
+    if(buf->encoder != NULL) {
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NDocSaveTo: output buffer encoder != NULL but C14N requires UTF8 output\n");
+        return(-1);
+    }
+
+    ctx = xmlC14NNewCtx(doc, nodes, exclusive, inclusive_ns_prefixes,
+		with_comments, buf);
+    if(ctx == NULL) {
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NDocSaveTo: unable to create C14N context\n");
+        return(-1);
+    }
+
+
+
+    /*  
+     * Root Node
+     * The root node is the parent of the top-level document element. The 
+     * result of processing each of its child nodes that is in the node-set 
+     * in document order. The root node does not generate a byte order mark, 
+     * XML declaration, nor anything from within the document type 
+     * declaration.
+     */
+    if(doc->children != NULL) {
+	ret = xmlC14NProcessNodeList(ctx, doc->children);  
+	if(ret < 0) {
+#ifdef DEBUG_C14N    
+    	    xmlGenericError(xmlGenericErrorContext,
+        	"xmlC14NDocSaveTo: process childrens' list failed.\n");
+#endif	
+	    xmlC14NFreeCtx(ctx);    
+    	    return(-1);
+	}
+    }    
+    
+    /*
+     * Flush buffer to get number of bytes written
+     */
+    ret = xmlOutputBufferFlush(buf);
+    if(ret < 0) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+    	    "xmlC14NDocSaveTo: buffer flush failed.\n");
+#endif	
+	xmlC14NFreeCtx(ctx);    
+    	return(-1);
+    }
+
+    /* 
+     * Cleanup
+     */
+    xmlC14NFreeCtx(ctx);    
+    return(ret);
+}
+
+/**
+ * xmlC14NDocDumpMemory:
+ * @doc: 		the XML document for canonization
+ * @nodes: 		the nodes set to be included in the canonized image
+ *      		or NULL if all document nodes should be included
+ * @exclusive:		the exclusive flag (0 - non-exclusive canonicalization;
+ *			otherwise - exclusive canonicalization)
+ * @inclusive_ns_prefixe the list of inclusive namespace prefixes 
+ *			ended with a NULL or NULL if there is no
+ *			inclusive namespaces (only for exclusive 
+ *			canonicalization, ignored otherwise)
+ * @with_comments: 	include comments in the result (!=0) or not (==0)
+ * @doc_txt_ptr: 	the memory pointer for allocated canonical XML text;
+ *			the caller of this functions is responsible for calling
+ *			xmlFree() to free allocated memory 
+ *  		
+ * Dumps the canonized image of given XML document into memory.
+ * For details see "Canonical XML" (http://www.w3.org/TR/xml-c14n) or
+ * "Exclusive XML Canonicalization" (http://www.w3.org/TR/xml-exc-c14n)
+ *
+ * Returns the number of bytes written on success or a negative value on fail  
+ */
+int
+xmlC14NDocDumpMemory(xmlDocPtr doc, xmlNodeSetPtr nodes, 
+		int exclusive, xmlChar **inclusive_ns_prefixes,
+		int with_comments, 
+		xmlChar **doc_txt_ptr) {
+    int ret;
+    xmlOutputBufferPtr buf;
+
+    if (doc_txt_ptr == NULL) {
+#ifdef DEBUG_C14N 	
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NDocDumpMemory:  null return buffer pointer\n");
+#endif 	    
+        return(-1);
+    }
+
+    *doc_txt_ptr = NULL;
+    
+    /*
+     * create memory buffer with UTF8 (default) encoding 
+     */
+    buf = xmlAllocOutputBuffer(NULL);
+    if(buf == NULL ) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+	    "xmlC14NDocDumpMemory: failed to allocate output buffer.\n");
+#endif	    
+        return(-1);
+    }
+
+    /*
+     * canonize document and write to buffer
+     */
+    ret = xmlC14NDocSaveTo(doc, nodes, exclusive, inclusive_ns_prefixes, 
+	    with_comments, buf);
+    if(ret < 0) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+	    "xmlC14NDocDumpMemory: xmlC14NDocSaveTo failed.\n");
+#endif	    
+	(void)xmlOutputBufferClose(buf);
+        return(-1);
+    }    
+
+    ret = buf->buffer->use;    
+    if(ret > 0) {
+	*doc_txt_ptr = xmlStrndup(buf->buffer->content, ret);
+    }
+    (void)xmlOutputBufferClose(buf);
+
+    if(*doc_txt_ptr == NULL && ret > 0) {
+#ifdef DEBUG_C14N 	
+        xmlGenericError(xmlGenericErrorContext,
+                "xmlC14NDocDumpMemory: failed to allocate memory for document text representation\n");
+#endif 		
+	return(-1);
+    }
+    return(ret);        
+}
+
+/**
+ * xmlC14NDocSave:
+ * @doc: 		the XML document for canonization
+ * @nodes: 		the nodes set to be included in the canonized image
+ *      		or NULL if all document nodes should be included
+ * @exclusive:		the exclusive flag (0 - non-exclusive canonicalization;
+ *			otherwise - exclusive canonicalization)
+ * @inclusive_ns_prefixe the list of inclusive namespace prefixes 
+ *			ended with a NULL or NULL if there is no
+ *			inclusive namespaces (only for exclusive 
+ *			canonicalization, ignored otherwise)
+ * @with_comments: 	include comments in the result (!=0) or not (==0)
+ * @filename: 		the filename to store canonical XML image
+ * @compression:	the compression level (zlib requred): 
+ *				-1 - libxml default,
+ *				 0 - uncompressed, 
+ *				>0 - compression level
+ *  		
+ * Dumps the canonized image of given XML document into the file.
+ * For details see "Canonical XML" (http://www.w3.org/TR/xml-c14n) or
+ * "Exclusive XML Canonicalization" (http://www.w3.org/TR/xml-exc-c14n)
+ *
+ * Returns the number of bytes written success or a negative value on fail  
+ */
+int
+xmlC14NDocSave(xmlDocPtr doc, xmlNodeSetPtr nodes, 
+		int exclusive, xmlChar **inclusive_ns_prefixes,
+		int with_comments, 
+		const char* filename, int compression) {
+    xmlOutputBufferPtr buf;    
+    int ret;
+
+    if(filename == NULL) {
+#ifdef DEBUG_C14N 	
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NDocSave:  filename is NULL\n");
+#endif 	    
+        return(-1);
+    }
+    
+#ifdef HAVE_ZLIB_H
+    if(compression < 0) compression = xmlGetCompressMode();
+#endif    
+
+    /* 
+     * save the content to a temp buffer, use default UTF8 encoding.
+     */
+    buf = xmlOutputBufferCreateFilename(filename, NULL, compression);
+    if (buf == NULL) {
+#ifdef DEBUG_C14N 	
+        xmlGenericError(xmlGenericErrorContext,
+            "xmlC14NDocSave:  unable to create buffer for file=\"%s\" with compressin=%d\n", filename, compression);
+#endif 	    
+	return(-1);
+    }
+    
+    /*
+     * canonize document and write to buffer
+     */
+    ret = xmlC14NDocSaveTo(doc, nodes, exclusive, inclusive_ns_prefixes, 
+	    with_comments, buf);
+    if(ret < 0) {
+#ifdef DEBUG_C14N    
+        xmlGenericError(xmlGenericErrorContext,
+	    "xmlC14NDocSave: xmlC14NDocSaveTo failed.\n");
+#endif	    
+	(void)xmlOutputBufferClose(buf);
+        return(-1);
+    }
+    
+    /* 
+     * get the numbers of bytes written 
+     */
+    ret = xmlOutputBufferClose(buf);
+    return(ret);
+}
+
+
+
+/*
+ * Macro used to grow the current buffer.
+ */
+#define growBufferReentrant() {						\
+    buffer_size *= 2;							\
+    buffer = (xmlChar *)						\
+    		xmlRealloc(buffer, buffer_size * sizeof(xmlChar));	\
+    if (buffer == NULL) {						\
+	perror("realloc failed");					\
+	return(NULL);							\
+    }									\
+}
+
+/** 
+ * xmlC11NNormalizeString:
+ * @input:		the input string
+ * @mode:		the normalization mode (attribute, comment, PI or text)
+ *
+ * Converts a string to a canonical (normalized) format. The code is stolen
+ * from xmlEncodeEntitiesReentrant(). Added normalization of \x09, \x0a, \x0A
+ * and the @mode parameter
+ *
+ * Returns a normalized string (caller is responsible for calling xmlFree())
+ * or NULL if an error occurs
+ */
+static xmlChar *
+xmlC11NNormalizeString(const xmlChar *input, xmlC14NNormalizationMode mode) {
+    const xmlChar *cur = input;
+    xmlChar *buffer = NULL;
+    xmlChar *out = NULL;
+    int buffer_size = 0;
+
+    if (input == NULL) return(NULL);
+
+    /*
+     * allocate an translation buffer.
+     */
+    buffer_size = 1000;
+    buffer = (xmlChar *) xmlMalloc(buffer_size * sizeof(xmlChar));
+    if (buffer == NULL) {
+	perror("malloc failed");
+	return(NULL);
+    }
+    out = buffer;
+
+    while (*cur != '\0') {
+        if (out - buffer > buffer_size - 10) {
+	    int indx = out - buffer;
+
+	    growBufferReentrant();
+	    out = &buffer[indx];
+	}
+
+	if (*cur == '<' && (mode == XMLC14N_NORMALIZE_ATTR ||
+				mode == XMLC14N_NORMALIZE_TEXT)) {
+	    *out++ = '&';
+	    *out++ = 'l';
+	    *out++ = 't';
+	    *out++ = ';';
+	} else if (*cur == '>' && (mode == XMLC14N_NORMALIZE_TEXT)) {
+	    *out++ = '&';
+	    *out++ = 'g';
+	    *out++ = 't';
+	    *out++ = ';';
+	} else if (*cur == '&' && (mode == XMLC14N_NORMALIZE_ATTR ||
+				mode == XMLC14N_NORMALIZE_TEXT)) {
+	    *out++ = '&';
+	    *out++ = 'a';
+	    *out++ = 'm';
+	    *out++ = 'p';
+	    *out++ = ';';
+	} else if (*cur == '"' && (mode == XMLC14N_NORMALIZE_ATTR)) {
+	    *out++ = '&';
+	    *out++ = 'q';
+	    *out++ = 'u';
+	    *out++ = 'o';
+	    *out++ = 't';
+	    *out++ = ';';
+	} else if (*cur == '\x09' && (mode == XMLC14N_NORMALIZE_ATTR)) {
+	    *out++ = '&';
+	    *out++ = '#';
+	    *out++ = 'x';
+	    *out++ = '9';
+	    *out++ = ';';
+	} else if (*cur == '\x0A' && (mode == XMLC14N_NORMALIZE_ATTR)) {
+	    *out++ = '&';
+	    *out++ = '#';
+	    *out++ = 'x';
+	    *out++ = 'A';
+	    *out++ = ';';
+	} else if (*cur == '\x0D' && (mode == XMLC14N_NORMALIZE_ATTR ||
+				mode == XMLC14N_NORMALIZE_TEXT ||
+				mode == XMLC14N_NORMALIZE_COMMENT ||
+				mode == XMLC14N_NORMALIZE_PI)) {
+	    *out++ = '&';
+	    *out++ = '#';
+	    *out++ = 'x';
+	    *out++ = 'D';
+	    *out++ = ';';
+	} else {
+	    /*
+	     * Works because on UTF-8, all extended sequences cannot
+	     * result in bytes in the ASCII range.
+	     */
+	    *out++ = *cur;
+	}
+	cur++;
+    }
+    *out++ = 0;
+    return(buffer);
+}
+
+#endif /* LIBXML_C14N_ENABLED */