/*
 * xinclude.c : Code to implement XInclude processing
 *
 * World Wide Web Consortium W3C Last Call Working Draft 10 November 2003
 * http://www.w3.org/TR/2003/WD-xinclude-20031110
 *
 * See Copyright for the status of this software.
 *
 * daniel@veillard.com
 */

#define IN_LIBXML
#include "libxml.h"

#include <string.h>
#include <libxml/xmlmemory.h>
#include <libxml/tree.h>
#include <libxml/parser.h>
#include <libxml/uri.h>
#include <libxml/xpointer.h>
#include <libxml/parserInternals.h>
#include <libxml/xmlerror.h>
#include <libxml/encoding.h>
#include <libxml/globals.h>

#ifdef LIBXML_XINCLUDE_ENABLED
#include <libxml/xinclude.h>


#define XINCLUDE_MAX_DEPTH 40

/* #define DEBUG_XINCLUDE */
#ifdef DEBUG_XINCLUDE
#ifdef LIBXML_DEBUG_ENABLED
#include <libxml/debugXML.h>
#endif
#endif

/************************************************************************
 *                                                                      *
 *                      XInclude context handling                       *
 *                                                                      *
 ************************************************************************/

/*
 * An XInclude context
 */
typedef xmlChar *xmlURL;

typedef struct _xmlXIncludeRef xmlXIncludeRef;
typedef xmlXIncludeRef *xmlXIncludeRefPtr;
struct _xmlXIncludeRef {
    xmlChar              *URI; /* the fully resolved resource URL */
    xmlChar         *fragment; /* the fragment in the URI */
    xmlDocPtr             doc; /* the parsed document */
    xmlNodePtr            ref; /* the node making the reference in the source */
    xmlNodePtr            inc; /* the included copy */
    int                   xml; /* xml or txt */
    int                 count; /* how many refs use that specific doc */
    xmlXPathObjectPtr    xptr; /* the xpointer if needed */
    int               emptyFb; /* flag to show fallback empty */
};

struct _xmlXIncludeCtxt {
    xmlDocPtr             doc; /* the source document */
    int               incBase; /* the first include for this document */
    int                 incNr; /* number of includes */
    int                incMax; /* size of includes tab */
    xmlXIncludeRefPtr *incTab; /* array of included references */

    int                 txtNr; /* number of unparsed documents */
    int                txtMax; /* size of unparsed documents tab */
    xmlNodePtr        *txtTab; /* array of unparsed text nodes */
    xmlURL         *txturlTab; /* array of unparsed text URLs */

    xmlChar *             url; /* the current URL processed */
    int                 urlNr; /* number of URLs stacked */
    int                urlMax; /* size of URL stack */
    xmlChar *         *urlTab; /* URL stack */

    int              nbErrors; /* the number of errors detected */
    int                legacy; /* using XINCLUDE_OLD_NS */
    int            parseFlags; /* the flags used for parsing XML documents */
    xmlChar *            base; /* the current xml:base */

    void            *_private; /* application data */
};

static int
xmlXIncludeDoProcess(xmlXIncludeCtxtPtr ctxt, xmlDocPtr doc, xmlNodePtr tree);


/************************************************************************
 *                                                                      *
 *                      XInclude error handler                          *
 *                                                                      *
 ************************************************************************/

/**
 * xmlXIncludeErrMemory:
 * @extra:  extra information
 *
 * Handle an out of memory condition
 */
static void
xmlXIncludeErrMemory(xmlXIncludeCtxtPtr ctxt, xmlNodePtr node,
                     const char *extra)
{
    if (ctxt != NULL)
        ctxt->nbErrors++;
    __xmlRaiseError(NULL, NULL, NULL, ctxt, node, XML_FROM_XINCLUDE,
                    XML_ERR_NO_MEMORY, XML_ERR_ERROR, NULL, 0,
                    extra, NULL, NULL, 0, 0,
                    "Memory allocation failed : %s\n", extra);
}

/**
 * xmlXIncludeErr:
 * @ctxt: the XInclude context
 * @node: the context node
 * @msg:  the error message
 * @extra:  extra information
 *
 * Handle an XInclude error
 */
static void
xmlXIncludeErr(xmlXIncludeCtxtPtr ctxt, xmlNodePtr node, int error,
               const char *msg, const xmlChar *extra)
{
    if (ctxt != NULL)
        ctxt->nbErrors++;
    __xmlRaiseError(NULL, NULL, NULL, ctxt, node, XML_FROM_XINCLUDE,
                    error, XML_ERR_ERROR, NULL, 0,
                    (const char *) extra, NULL, NULL, 0, 0,
                    msg, (const char *) extra);
}

#if 0
/**
 * xmlXIncludeWarn:
 * @ctxt: the XInclude context
 * @node: the context node
 * @msg:  the error message
 * @extra:  extra information
 *
 * Emit an XInclude warning.
 */
static void
xmlXIncludeWarn(xmlXIncludeCtxtPtr ctxt, xmlNodePtr node, int error,
               const char *msg, const xmlChar *extra)
{
    __xmlRaiseError(NULL, NULL, NULL, ctxt, node, XML_FROM_XINCLUDE,
                    error, XML_ERR_WARNING, NULL, 0,
                    (const char *) extra, NULL, NULL, 0, 0,
                    msg, (const char *) extra);
}
#endif

/**
 * xmlXIncludeGetProp:
 * @ctxt:  the XInclude context
 * @cur:  the node
 * @name:  the attribute name
 *
 * Get an XInclude attribute
 *
 * Returns the value (to be freed) or NULL if not found
 */
static xmlChar *
xmlXIncludeGetProp(xmlXIncludeCtxtPtr ctxt, xmlNodePtr cur,
                   const xmlChar *name) {
    xmlChar *ret;

    ret = xmlGetNsProp(cur, XINCLUDE_NS, name);
    if (ret != NULL)
        return(ret);
    if (ctxt->legacy != 0) {
        ret = xmlGetNsProp(cur, XINCLUDE_OLD_NS, name);
        if (ret != NULL)
            return(ret);
    }
    ret = xmlGetProp(cur, name);
    return(ret);
}
/**
 * xmlXIncludeFreeRef:
 * @ref: the XInclude reference
 *
 * Free an XInclude reference
 */
static void
xmlXIncludeFreeRef(xmlXIncludeRefPtr ref) {
    if (ref == NULL)
        return;
#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "Freeing ref\n");
#endif
    if (ref->doc != NULL) {
#ifdef DEBUG_XINCLUDE
        xmlGenericError(xmlGenericErrorContext, "Freeing doc %s\n", ref->URI);
#endif
        xmlFreeDoc(ref->doc);
    }
    if (ref->URI != NULL)
        xmlFree(ref->URI);
    if (ref->fragment != NULL)
        xmlFree(ref->fragment);
    if (ref->xptr != NULL)
        xmlXPathFreeObject(ref->xptr);
    xmlFree(ref);
}

/**
 * xmlXIncludeNewRef:
 * @ctxt: the XInclude context
 * @URI:  the resource URI
 *
 * Creates a new reference within an XInclude context
 *
 * Returns the new set
 */
static xmlXIncludeRefPtr
xmlXIncludeNewRef(xmlXIncludeCtxtPtr ctxt, const xmlChar *URI,
                  xmlNodePtr ref) {
    xmlXIncludeRefPtr ret;

#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "New ref %s\n", URI);
#endif
    ret = (xmlXIncludeRefPtr) xmlMalloc(sizeof(xmlXIncludeRef));
    if (ret == NULL) {
        xmlXIncludeErrMemory(ctxt, ref, "growing XInclude context");
        return(NULL);
    }
    memset(ret, 0, sizeof(xmlXIncludeRef));
    if (URI == NULL)
        ret->URI = NULL;
    else
        ret->URI = xmlStrdup(URI);
    ret->fragment = NULL;
    ret->ref = ref;
    ret->doc = NULL;
    ret->count = 0;
    ret->xml = 0;
    ret->inc = NULL;
    if (ctxt->incMax == 0) {
        ctxt->incMax = 4;
        ctxt->incTab = (xmlXIncludeRefPtr *) xmlMalloc(ctxt->incMax *
                                              sizeof(ctxt->incTab[0]));
        if (ctxt->incTab == NULL) {
            xmlXIncludeErrMemory(ctxt, ref, "growing XInclude context");
            xmlXIncludeFreeRef(ret);
            return(NULL);
        }
    }
    if (ctxt->incNr >= ctxt->incMax) {
        ctxt->incMax *= 2;
        ctxt->incTab = (xmlXIncludeRefPtr *) xmlRealloc(ctxt->incTab,
                     ctxt->incMax * sizeof(ctxt->incTab[0]));
        if (ctxt->incTab == NULL) {
            xmlXIncludeErrMemory(ctxt, ref, "growing XInclude context");
            xmlXIncludeFreeRef(ret);
            return(NULL);
        }
    }
    ctxt->incTab[ctxt->incNr++] = ret;
    return(ret);
}

/**
 * xmlXIncludeNewContext:
 * @doc:  an XML Document
 *
 * Creates a new XInclude context
 *
 * Returns the new set
 */
xmlXIncludeCtxtPtr
xmlXIncludeNewContext(xmlDocPtr doc) {
    xmlXIncludeCtxtPtr ret;

#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "New context\n");
#endif
    if (doc == NULL)
        return(NULL);
    ret = (xmlXIncludeCtxtPtr) xmlMalloc(sizeof(xmlXIncludeCtxt));
    if (ret == NULL) {
        xmlXIncludeErrMemory(NULL, (xmlNodePtr) doc,
                             "creating XInclude context");
        return(NULL);
    }
    memset(ret, 0, sizeof(xmlXIncludeCtxt));
    ret->doc = doc;
    ret->incNr = 0;
    ret->incBase = 0;
    ret->incMax = 0;
    ret->incTab = NULL;
    ret->nbErrors = 0;
    return(ret);
}

/**
 * xmlXIncludeURLPush:
 * @ctxt:  the parser context
 * @value:  the url
 *
 * Pushes a new url on top of the url stack
 *
 * Returns -1 in case of error, the index in the stack otherwise
 */
static int
xmlXIncludeURLPush(xmlXIncludeCtxtPtr ctxt,
                   const xmlChar *value)
{
    if (ctxt->urlNr > XINCLUDE_MAX_DEPTH) {
        xmlXIncludeErr(ctxt, NULL, XML_XINCLUDE_RECURSION,
                       "detected a recursion in %s\n", value);
        return(-1);
    }
    if (ctxt->urlTab == NULL) {
        ctxt->urlMax = 4;
        ctxt->urlNr = 0;
        ctxt->urlTab = (xmlChar * *) xmlMalloc(
                        ctxt->urlMax * sizeof(ctxt->urlTab[0]));
        if (ctxt->urlTab == NULL) {
            xmlXIncludeErrMemory(ctxt, NULL, "adding URL");
            return (-1);
        }
    }
    if (ctxt->urlNr >= ctxt->urlMax) {
        ctxt->urlMax *= 2;
        ctxt->urlTab =
            (xmlChar * *) xmlRealloc(ctxt->urlTab,
                                      ctxt->urlMax *
                                      sizeof(ctxt->urlTab[0]));
        if (ctxt->urlTab == NULL) {
            xmlXIncludeErrMemory(ctxt, NULL, "adding URL");
            return (-1);
        }
    }
    ctxt->url = ctxt->urlTab[ctxt->urlNr] = xmlStrdup(value);
    return (ctxt->urlNr++);
}

/**
 * xmlXIncludeURLPop:
 * @ctxt: the parser context
 *
 * Pops the top URL from the URL stack
 */
static void
xmlXIncludeURLPop(xmlXIncludeCtxtPtr ctxt)
{
    xmlChar * ret;

    if (ctxt->urlNr <= 0)
        return;
    ctxt->urlNr--;
    if (ctxt->urlNr > 0)
        ctxt->url = ctxt->urlTab[ctxt->urlNr - 1];
    else
        ctxt->url = NULL;
    ret = ctxt->urlTab[ctxt->urlNr];
    ctxt->urlTab[ctxt->urlNr] = NULL;
    if (ret != NULL)
        xmlFree(ret);
}

/**
 * xmlXIncludeFreeContext:
 * @ctxt: the XInclude context
 *
 * Free an XInclude context
 */
void
xmlXIncludeFreeContext(xmlXIncludeCtxtPtr ctxt) {
    int i;

#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "Freeing context\n");
#endif
    if (ctxt == NULL)
        return;
    while (ctxt->urlNr > 0)
        xmlXIncludeURLPop(ctxt);
    if (ctxt->urlTab != NULL)
        xmlFree(ctxt->urlTab);
    for (i = 0;i < ctxt->incNr;i++) {
        if (ctxt->incTab[i] != NULL)
            xmlXIncludeFreeRef(ctxt->incTab[i]);
    }
    if (ctxt->txturlTab != NULL) {
        for (i = 0;i < ctxt->txtNr;i++) {
            if (ctxt->txturlTab[i] != NULL)
                xmlFree(ctxt->txturlTab[i]);
        }
    }
    if (ctxt->incTab != NULL)
        xmlFree(ctxt->incTab);
    if (ctxt->txtTab != NULL)
        xmlFree(ctxt->txtTab);
    if (ctxt->txturlTab != NULL)
        xmlFree(ctxt->txturlTab);
    if (ctxt->base != NULL) {
        xmlFree(ctxt->base);
    }
    xmlFree(ctxt);
}

/**
 * xmlXIncludeParseFile:
 * @ctxt:  the XInclude context
 * @URL:  the URL or file path
 * 
 * parse a document for XInclude
 */
static xmlDocPtr
xmlXIncludeParseFile(xmlXIncludeCtxtPtr ctxt, const char *URL) {
    xmlDocPtr ret;
    xmlParserCtxtPtr pctxt;
    char *directory = NULL;
    xmlParserInputPtr inputStream;

    xmlInitParser();

    pctxt = xmlNewParserCtxt();
    if (pctxt == NULL) {
        xmlXIncludeErrMemory(ctxt, NULL, "cannot allocate parser context");
        return(NULL);
    }

    /*
     * pass in the application data to the parser context.
     */
    pctxt->_private = ctxt->_private;
    
    /*
     * try to ensure that new documents included are actually
     * built with the same dictionary as the including document.
     */
    if ((ctxt->doc != NULL) && (ctxt->doc->dict != NULL) &&
        (pctxt->dict != NULL)) {
        xmlDictFree(pctxt->dict);
        pctxt->dict = ctxt->doc->dict;
        xmlDictReference(pctxt->dict);
    }

    xmlCtxtUseOptions(pctxt, ctxt->parseFlags | XML_PARSE_DTDLOAD);
    
    inputStream = xmlLoadExternalEntity(URL, NULL, pctxt);
    if (inputStream == NULL) {
        xmlFreeParserCtxt(pctxt);
        return(NULL);
    }

    inputPush(pctxt, inputStream);

    if ((pctxt->directory == NULL) && (directory == NULL))
        directory = xmlParserGetDirectory(URL);
    if ((pctxt->directory == NULL) && (directory != NULL))
        pctxt->directory = (char *) xmlStrdup((xmlChar *) directory);

    pctxt->loadsubset |= XML_DETECT_IDS;

    xmlParseDocument(pctxt);

    if (pctxt->wellFormed) {
        ret = pctxt->myDoc;
    }
    else {
        ret = NULL;
        if (pctxt->myDoc != NULL)
            xmlFreeDoc(pctxt->myDoc);
        pctxt->myDoc = NULL;
    }
    xmlFreeParserCtxt(pctxt);
    
    return(ret);
}

/**
 * xmlXIncludeAddNode:
 * @ctxt:  the XInclude context
 * @cur:  the new node
 * 
 * Add a new node to process to an XInclude context
 */
static int
xmlXIncludeAddNode(xmlXIncludeCtxtPtr ctxt, xmlNodePtr cur) {
    xmlXIncludeRefPtr ref;
    xmlURIPtr uri;
    xmlChar *URL;
    xmlChar *fragment = NULL;
    xmlChar *href;
    xmlChar *parse;
    xmlChar *base;
    xmlChar *URI;
    int xml = 1, i; /* default Issue 64 */
    int local = 0;


    if (ctxt == NULL)
        return(-1);
    if (cur == NULL)
        return(-1);

#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "Add node\n");
#endif
    /*
     * read the attributes
     */
    href = xmlXIncludeGetProp(ctxt, cur, XINCLUDE_HREF);
    if (href == NULL) {
        href = xmlStrdup(BAD_CAST ""); /* @@@@ href is now optional */
        if (href == NULL) 
            return(-1);
        local = 1;
    }
    if (href[0] == '#')
        local = 1;
    parse = xmlXIncludeGetProp(ctxt, cur, XINCLUDE_PARSE);
    if (parse != NULL) {
        if (xmlStrEqual(parse, XINCLUDE_PARSE_XML))
            xml = 1;
        else if (xmlStrEqual(parse, XINCLUDE_PARSE_TEXT))
            xml = 0;
        else {
            xmlXIncludeErr(ctxt, cur, XML_XINCLUDE_PARSE_VALUE,
                           "invalid value %s for 'parse'\n", parse);
            if (href != NULL)
                xmlFree(href);
            if (parse != NULL)
                xmlFree(parse);
            return(-1);
        }
    }

    /*
     * compute the URI
     */
    base = xmlNodeGetBase(ctxt->doc, cur);
    if (base == NULL) {
        URI = xmlBuildURI(href, ctxt->doc->URL);
    } else {
        URI = xmlBuildURI(href, base);
    }
    if (URI == NULL) {
        xmlChar *escbase;
        xmlChar *eschref;
        /*
         * Some escaping may be needed
         */
        escbase = xmlURIEscape(base);
        eschref = xmlURIEscape(href);
        URI = xmlBuildURI(eschref, escbase);
        if (escbase != NULL)
            xmlFree(escbase);
        if (eschref != NULL)
            xmlFree(eschref);
    }
    if (parse != NULL)
        xmlFree(parse);
    if (href != NULL)
        xmlFree(href);
    if (base != NULL)
        xmlFree(base);
    if (URI == NULL) {
        xmlXIncludeErr(ctxt, cur, XML_XINCLUDE_HREF_URI,
                       "failed build URL\n", NULL);
        return(-1);
    }
    fragment = xmlXIncludeGetProp(ctxt, cur, XINCLUDE_PARSE_XPOINTER);

    /*
     * Check the URL and remove any fragment identifier
     */
    uri = xmlParseURI((const char *)URI);
    if (uri == NULL) {
        xmlXIncludeErr(ctxt, cur, XML_XINCLUDE_HREF_URI,
                       "invalid value URI %s\n", URI);
        if (fragment != NULL)
            xmlFree(fragment);
        xmlFree(URI);
        return(-1);
    }

    if (uri->fragment != NULL) {
        if (ctxt->legacy != 0) {
            if (fragment == NULL) {
                fragment = (xmlChar *) uri->fragment;
            } else {
                xmlFree(uri->fragment);
            }
        } else {
            xmlXIncludeErr(ctxt, cur, XML_XINCLUDE_FRAGMENT_ID,
       "Invalid fragment identifier in URI %s use the xpointer attribute\n",
                           URI);
            if (fragment != NULL)
                xmlFree(fragment);
            xmlFreeURI(uri);
            xmlFree(URI);
            return(-1);
        }
        uri->fragment = NULL;
    }
    URL = xmlSaveUri(uri);
    xmlFreeURI(uri);
    xmlFree(URI);
    if (URL == NULL) {
        xmlXIncludeErr(ctxt, cur, XML_XINCLUDE_HREF_URI,
                       "invalid value URI %s\n", URI);
        if (fragment != NULL)
            xmlFree(fragment);
        return(-1);
    }

    /*
     * Check the URL against the stack for recursions
     */
    if ((!local) && (xml == 1)) {
        for (i = 0;i < ctxt->urlNr;i++) {
            if (xmlStrEqual(URL, ctxt->urlTab[i])) {
                xmlXIncludeErr(ctxt, cur, XML_XINCLUDE_RECURSION,
                               "detected a recursion in %s\n", URL);
                return(-1);
            }
        }
    }

    ref = xmlXIncludeNewRef(ctxt, URL, cur);
    if (ref == NULL) {
        return(-1);
    }
    ref->fragment = fragment;
    ref->doc = NULL;
    ref->xml = xml;
    ref->count = 1;
    xmlFree(URL);
    return(0);
}

/**
 * xmlXIncludeRecurseDoc:
 * @ctxt:  the XInclude context
 * @doc:  the new document
 * @url:  the associated URL
 * 
 * The XInclude recursive nature is handled at this point.
 */
static void
xmlXIncludeRecurseDoc(xmlXIncludeCtxtPtr ctxt, xmlDocPtr doc,
                      const xmlURL url ATTRIBUTE_UNUSED) {
    xmlXIncludeCtxtPtr newctxt;
    int i;

    /*
     * Avoid recursion in already substitued resources
    for (i = 0;i < ctxt->urlNr;i++) {
        if (xmlStrEqual(doc->URL, ctxt->urlTab[i]))
            return;
    }
     */

#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "Recursing in doc %s\n", doc->URL);
#endif
    /*
     * Handle recursion here.
     */

    newctxt = xmlXIncludeNewContext(doc);
    if (newctxt != NULL) {
        /*
         * Copy the existing document set
         */
        newctxt->incMax = ctxt->incMax;
        newctxt->incNr = ctxt->incNr;
        newctxt->incTab = (xmlXIncludeRefPtr *) xmlMalloc(newctxt->incMax *
                                          sizeof(newctxt->incTab[0]));
        if (newctxt->incTab == NULL) {
            xmlXIncludeErrMemory(ctxt, (xmlNodePtr) doc, "processing doc");
            xmlFree(newctxt);
            return;
        }
        /*
         * copy the urlTab
         */
        newctxt->urlMax = ctxt->urlMax;
        newctxt->urlNr = ctxt->urlNr;
        newctxt->urlTab = ctxt->urlTab;

        /*
         * Inherit the existing base
         */
        newctxt->base = xmlStrdup(ctxt->base);

        /*
         * Inherit the documents already in use by other includes
         */
        newctxt->incBase = ctxt->incNr;
        for (i = 0;i < ctxt->incNr;i++) {
            newctxt->incTab[i] = ctxt->incTab[i];
            newctxt->incTab[i]->count++; /* prevent the recursion from
                                            freeing it */
        }
        /*
         * The new context should also inherit the Parse Flags
         * (bug 132597)
         */
        newctxt->parseFlags = ctxt->parseFlags;
        xmlXIncludeDoProcess(newctxt, doc, xmlDocGetRootElement(doc));
        for (i = 0;i < ctxt->incNr;i++) {
            newctxt->incTab[i]->count--;
            newctxt->incTab[i] = NULL;
        }

        /* urlTab may have been reallocated */
        ctxt->urlTab = newctxt->urlTab;
        ctxt->urlMax = newctxt->urlMax;

        newctxt->urlMax = 0;
        newctxt->urlNr = 0;
        newctxt->urlTab = NULL;

        xmlXIncludeFreeContext(newctxt);
    }
#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "Done recursing in doc %s\n", url);
#endif
}

/**
 * xmlXIncludeAddTxt:
 * @ctxt:  the XInclude context
 * @txt:  the new text node
 * @url:  the associated URL
 * 
 * Add a new txtument to the list
 */
static void
xmlXIncludeAddTxt(xmlXIncludeCtxtPtr ctxt, xmlNodePtr txt, const xmlURL url) {
#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "Adding text %s\n", url);
#endif
    if (ctxt->txtMax == 0) {
        ctxt->txtMax = 4;
        ctxt->txtTab = (xmlNodePtr *) xmlMalloc(ctxt->txtMax *
                                          sizeof(ctxt->txtTab[0]));
        if (ctxt->txtTab == NULL) {
            xmlXIncludeErrMemory(ctxt, NULL, "processing text");
            return;
        }
        ctxt->txturlTab = (xmlURL *) xmlMalloc(ctxt->txtMax *
                                          sizeof(ctxt->txturlTab[0]));
        if (ctxt->txturlTab == NULL) {
            xmlXIncludeErrMemory(ctxt, NULL, "processing text");
            return;
        }
    }
    if (ctxt->txtNr >= ctxt->txtMax) {
        ctxt->txtMax *= 2;
        ctxt->txtTab = (xmlNodePtr *) xmlRealloc(ctxt->txtTab,
                     ctxt->txtMax * sizeof(ctxt->txtTab[0]));
        if (ctxt->txtTab == NULL) {
            xmlXIncludeErrMemory(ctxt, NULL, "processing text");
            return;
        }
        ctxt->txturlTab = (xmlURL *) xmlRealloc(ctxt->txturlTab,
                     ctxt->txtMax * sizeof(ctxt->txturlTab[0]));
        if (ctxt->txturlTab == NULL) {
            xmlXIncludeErrMemory(ctxt, NULL, "processing text");
            return;
        }
    }
    ctxt->txtTab[ctxt->txtNr] = txt;
    ctxt->txturlTab[ctxt->txtNr] = xmlStrdup(url);
    ctxt->txtNr++;
}

/************************************************************************
 *                                                                      *
 *                      Node copy with specific semantic                *
 *                                                                      *
 ************************************************************************/

/**
 * xmlXIncludeCopyNode:
 * @ctxt:  the XInclude context
 * @target:  the document target
 * @source:  the document source
 * @elem:  the element
 * 
 * Make a copy of the node while preserving the XInclude semantic
 * of the Infoset copy
 */
static xmlNodePtr
xmlXIncludeCopyNode(xmlXIncludeCtxtPtr ctxt, xmlDocPtr target,
                    xmlDocPtr source, xmlNodePtr elem) {
    xmlNodePtr result = NULL;

    if ((ctxt == NULL) || (target == NULL) || (source == NULL) ||
        (elem == NULL))
        return(NULL);
    if (elem->type == XML_DTD_NODE)
        return(NULL);
    result = xmlDocCopyNode(elem, target, 1);
    return(result);
}

/**
 * xmlXIncludeCopyNodeList:
 * @ctxt:  the XInclude context
 * @target:  the document target
 * @source:  the document source
 * @elem:  the element list
 * 
 * Make a copy of the node list while preserving the XInclude semantic
 * of the Infoset copy
 */
static xmlNodePtr
xmlXIncludeCopyNodeList(xmlXIncludeCtxtPtr ctxt, xmlDocPtr target,
                        xmlDocPtr source, xmlNodePtr elem) {
    xmlNodePtr cur, res, result = NULL, last = NULL;

    if ((ctxt == NULL) || (target == NULL) || (source == NULL) ||
        (elem == NULL))
        return(NULL);
    cur = elem;
    while (cur != NULL) {
        res = xmlXIncludeCopyNode(ctxt, target, source, cur);
        if (res != NULL) {
            if (result == NULL) {
                result = last = res;
            } else {
                last->next = res;
                res->prev = last;
                last = res;
            }
        }
        cur = cur->next;
    }
    return(result);
}

/**
 * xmlXIncludeGetNthChild:
 * @cur:  the node
 * @no:  the child number
 *
 * Returns the @n'th element child of @cur or NULL
 */
static xmlNodePtr
xmlXIncludeGetNthChild(xmlNodePtr cur, int no) {
    int i;
    if (cur == NULL) 
        return(cur);
    cur = cur->children;
    for (i = 0;i <= no;cur = cur->next) {
        if (cur == NULL) 
            return(cur);
        if ((cur->type == XML_ELEMENT_NODE) ||
            (cur->type == XML_DOCUMENT_NODE) ||
            (cur->type == XML_HTML_DOCUMENT_NODE)) {
            i++;
            if (i == no)
                break;
        }
    }
    return(cur);
}

xmlNodePtr xmlXPtrAdvanceNode(xmlNodePtr cur, int *level); /* in xpointer.c */
/**
 * xmlXIncludeCopyRange:
 * @ctxt:  the XInclude context
 * @target:  the document target
 * @source:  the document source
 * @obj:  the XPointer result from the evaluation.
 *
 * Build a node list tree copy of the XPointer result.
 *
 * Returns an xmlNodePtr list or NULL.
 *         The caller has to free the node tree.
 */
static xmlNodePtr
xmlXIncludeCopyRange(xmlXIncludeCtxtPtr ctxt, xmlDocPtr target,
                        xmlDocPtr source, xmlXPathObjectPtr range) {
    /* pointers to generated nodes */
    xmlNodePtr list = NULL, last = NULL, listParent = NULL;
    xmlNodePtr tmp, tmp2;
    /* pointers to traversal nodes */
    xmlNodePtr start, cur, end;
    int index1, index2;
    int level = 0, lastLevel = 0, endLevel = 0, endFlag = 0;

    if ((ctxt == NULL) || (target == NULL) || (source == NULL) ||
        (range == NULL))
        return(NULL);
    if (range->type != XPATH_RANGE)
        return(NULL);
    start = (xmlNodePtr) range->user;

    if (start == NULL)
        return(NULL);
    end = range->user2;
    if (end == NULL)
        return(xmlDocCopyNode(start, target, 1));

    cur = start;
    index1 = range->index;
    index2 = range->index2;
    /*
     * level is depth of the current node under consideration
     * list is the pointer to the root of the output tree
     * listParent is a pointer to the parent of output tree (within
       the included file) in case we need to add another level
     * last is a pointer to the last node added to the output tree
     * lastLevel is the depth of last (relative to the root)
     */
    while (cur != NULL) {
        /*
         * Check if our output tree needs a parent
         */
        if (level < 0) {
            while (level < 0) {
                /* copy must include namespaces and properties */
                tmp2 = xmlDocCopyNode(listParent, target, 2);
                xmlAddChild(tmp2, list);
                list = tmp2;
                listParent = listParent->parent;
                level++;
            }
            last = list;
            lastLevel = 0;
        }
        /*
         * Check whether we need to change our insertion point
         */
        while (level < lastLevel) {
            last = last->parent;
            lastLevel --;
        }
        if (cur == end) {       /* Are we at the end of the range? */
            if (cur->type == XML_TEXT_NODE) {
                const xmlChar *content = cur->content;
                int len;

                if (content == NULL) {
                    tmp = xmlNewTextLen(NULL, 0);
                } else {
                    len = index2;
                    if ((cur == start) && (index1 > 1)) {
                        content += (index1 - 1);
                        len -= (index1 - 1);
                        index1 = 0;
                    } else {
                        len = index2;
                    }
                    tmp = xmlNewTextLen(content, len);
                }
                /* single sub text node selection */
                if (list == NULL)
                    return(tmp);
                /* prune and return full set */
                if (level == lastLevel)
                    xmlAddNextSibling(last, tmp);
                else 
                    xmlAddChild(last, tmp);
                return(list);
            } else {    /* ending node not a text node */
                endLevel = level;       /* remember the level of the end node */
                endFlag = 1;
                /* last node - need to take care of properties + namespaces */
                tmp = xmlDocCopyNode(cur, target, 2);
                if (list == NULL) {
                    list = tmp;
                    listParent = cur->parent;
                } else {
                    if (level == lastLevel)
                        xmlAddNextSibling(last, tmp);
                    else {
                        xmlAddChild(last, tmp);
                        lastLevel = level;
                    }
                }
                last = tmp;

                if (index2 > 1) {
                    end = xmlXIncludeGetNthChild(cur, index2 - 1);
                    index2 = 0;
                }
                if ((cur == start) && (index1 > 1)) {
                    cur = xmlXIncludeGetNthChild(cur, index1 - 1);
                    index1 = 0;
                }  else {
                    cur = cur->children;
                }
                level++;        /* increment level to show change */
                /*
                 * Now gather the remaining nodes from cur to end
                 */
                continue;       /* while */
            }
        } else if (cur == start) {      /* Not at the end, are we at start? */
            if ((cur->type == XML_TEXT_NODE) ||
                (cur->type == XML_CDATA_SECTION_NODE)) {
                const xmlChar *content = cur->content;

                if (content == NULL) {
                    tmp = xmlNewTextLen(NULL, 0);
                } else {
                    if (index1 > 1) {
                        content += (index1 - 1);
                        index1 = 0;
                    }
                    tmp = xmlNewText(content);
                }
                last = list = tmp;
                listParent = cur->parent;
            } else {            /* Not text node */
                /*
                 * start of the range - need to take care of
                 * properties and namespaces
                 */
                tmp = xmlDocCopyNode(cur, target, 2);
                list = last = tmp;
                listParent = cur->parent;
                if (index1 > 1) {       /* Do we need to position? */
                    cur = xmlXIncludeGetNthChild(cur, index1 - 1);
                    level = lastLevel = 1;
                    index1 = 0;
                    /*
                     * Now gather the remaining nodes from cur to end
                     */
                    continue; /* while */
                }
            }
        } else {
            tmp = NULL;
            switch (cur->type) {
                case XML_DTD_NODE:
                case XML_ELEMENT_DECL:
                case XML_ATTRIBUTE_DECL:
                case XML_ENTITY_NODE:
                    /* Do not copy DTD informations */
                    break;
                case XML_ENTITY_DECL:
                    /* handle crossing entities -> stack needed */
                    break;
                case XML_XINCLUDE_START:
                case XML_XINCLUDE_END:
                    /* don't consider it part of the tree content */
                    break;
                case XML_ATTRIBUTE_NODE:
                    /* Humm, should not happen ! */
                    break;
                default:
                    /*
                     * Middle of the range - need to take care of
                     * properties and namespaces
                     */
                    tmp = xmlDocCopyNode(cur, target, 2);
                    break;
            }
            if (tmp != NULL) {
                if (level == lastLevel)
                    xmlAddNextSibling(last, tmp);
                else {
                    xmlAddChild(last, tmp);
                    lastLevel = level;
                }
                last = tmp;
            }
        }
        /*
         * Skip to next node in document order
         */
        cur = xmlXPtrAdvanceNode(cur, &level);
        if (endFlag && (level >= endLevel))
            break;
    }
    return(list);
}

/**
 * xmlXIncludeBuildNodeList:
 * @ctxt:  the XInclude context
 * @target:  the document target
 * @source:  the document source
 * @obj:  the XPointer result from the evaluation.
 *
 * Build a node list tree copy of the XPointer result.
 * This will drop Attributes and Namespace declarations.
 *
 * Returns an xmlNodePtr list or NULL.
 *         the caller has to free the node tree.
 */
static xmlNodePtr
xmlXIncludeCopyXPointer(xmlXIncludeCtxtPtr ctxt, xmlDocPtr target,
                        xmlDocPtr source, xmlXPathObjectPtr obj) {
    xmlNodePtr list = NULL, last = NULL;
    int i;

    if (source == NULL)
        source = ctxt->doc;
    if ((ctxt == NULL) || (target == NULL) || (source == NULL) ||
        (obj == NULL))
        return(NULL);
    switch (obj->type) {
        case XPATH_NODESET: {
            xmlNodeSetPtr set = obj->nodesetval;
            if (set == NULL)
                return(NULL);
            for (i = 0;i < set->nodeNr;i++) {
                if (set->nodeTab[i] == NULL)
                    continue;
                switch (set->nodeTab[i]->type) {
                    case XML_TEXT_NODE:
                    case XML_CDATA_SECTION_NODE:
                    case XML_ELEMENT_NODE:
                    case XML_ENTITY_REF_NODE:
                    case XML_ENTITY_NODE:
                    case XML_PI_NODE:
                    case XML_COMMENT_NODE:
                    case XML_DOCUMENT_NODE:
                    case XML_HTML_DOCUMENT_NODE:
#ifdef LIBXML_DOCB_ENABLED
                    case XML_DOCB_DOCUMENT_NODE:
#endif
                    case XML_XINCLUDE_END:
                        break;
                    case XML_XINCLUDE_START: {
                        xmlNodePtr tmp, cur = set->nodeTab[i];

                        cur = cur->next;
                        while (cur != NULL) {
                            switch(cur->type) {
                                case XML_TEXT_NODE:
                                case XML_CDATA_SECTION_NODE:
                                case XML_ELEMENT_NODE:
                                case XML_ENTITY_REF_NODE:
                                case XML_ENTITY_NODE:
                                case XML_PI_NODE:
                                case XML_COMMENT_NODE:
                                    tmp = xmlXIncludeCopyNode(ctxt, target,
                                                              source, cur);
                                    if (last == NULL) {
                                        list = last = tmp;
                                    } else {
                                        xmlAddNextSibling(last, tmp);
                                        last = tmp;
                                    }
                                    cur = cur->next;
                                    continue;
                                default:
                                    break;
                            }
                            break;
                        }
                        continue;
                    }
                    case XML_ATTRIBUTE_NODE:
                    case XML_NAMESPACE_DECL:
                    case XML_DOCUMENT_TYPE_NODE:
                    case XML_DOCUMENT_FRAG_NODE:
                    case XML_NOTATION_NODE:
                    case XML_DTD_NODE:
                    case XML_ELEMENT_DECL:
                    case XML_ATTRIBUTE_DECL:
                    case XML_ENTITY_DECL:
                        continue; /* for */
                }
                if (last == NULL)
                    list = last = xmlXIncludeCopyNode(ctxt, target, source,
                                                      set->nodeTab[i]);
                else {
                    xmlAddNextSibling(last,
                            xmlXIncludeCopyNode(ctxt, target, source,
                                                set->nodeTab[i]));
                    if (last->next != NULL)
                        last = last->next;
                }
            }
            break;
        }
        case XPATH_LOCATIONSET: {
            xmlLocationSetPtr set = (xmlLocationSetPtr) obj->user;
            if (set == NULL)
                return(NULL);
            for (i = 0;i < set->locNr;i++) {
                if (last == NULL)
                    list = last = xmlXIncludeCopyXPointer(ctxt, target, source,
                                                          set->locTab[i]);
                else
                    xmlAddNextSibling(last,
                            xmlXIncludeCopyXPointer(ctxt, target, source,
                                                    set->locTab[i]));
                if (last != NULL) {
                    while (last->next != NULL)
                        last = last->next;
                }
            }
            break;
        }
#ifdef LIBXML_XPTR_ENABLED
        case XPATH_RANGE:
            return(xmlXIncludeCopyRange(ctxt, target, source, obj));
#endif
        case XPATH_POINT:
            /* points are ignored in XInclude */
            break;
        default:
            break;
    }
    return(list);
}
/************************************************************************
 *                                                                      *
 *                      XInclude I/O handling                           *
 *                                                                      *
 ************************************************************************/

typedef struct _xmlXIncludeMergeData xmlXIncludeMergeData;
typedef xmlXIncludeMergeData *xmlXIncludeMergeDataPtr;
struct _xmlXIncludeMergeData {
    xmlDocPtr doc;
    xmlXIncludeCtxtPtr ctxt;
};

/**
 * xmlXIncludeMergeOneEntity:
 * @ent: the entity
 * @doc:  the including doc
 * @nr: the entity name
 *
 * Inplements the merge of one entity
 */
static void
xmlXIncludeMergeEntity(xmlEntityPtr ent, xmlXIncludeMergeDataPtr data,
                       xmlChar *name ATTRIBUTE_UNUSED) {
    xmlEntityPtr ret, prev;
    xmlDocPtr doc;
    xmlXIncludeCtxtPtr ctxt;

    if ((ent == NULL) || (data == NULL))
        return;
    ctxt = data->ctxt;
    doc = data->doc;
    if ((ctxt == NULL) || (doc == NULL))
        return;
    switch (ent->etype) {
        case XML_INTERNAL_PARAMETER_ENTITY:
        case XML_EXTERNAL_PARAMETER_ENTITY:
        case XML_INTERNAL_PREDEFINED_ENTITY:
            return;
        case XML_INTERNAL_GENERAL_ENTITY:
        case XML_EXTERNAL_GENERAL_PARSED_ENTITY:
        case XML_EXTERNAL_GENERAL_UNPARSED_ENTITY:
            break;
    }
    ret = xmlAddDocEntity(doc, ent->name, ent->etype, ent->ExternalID,
                          ent->SystemID, ent->content);
    if (ret != NULL) {
        if (ent->URI != NULL)
            ret->URI = xmlStrdup(ent->URI);
    } else {
        prev = xmlGetDocEntity(doc, ent->name);
        if (prev != NULL) {
            if (ent->etype != prev->etype)
                goto error;
        
            if ((ent->SystemID != NULL) && (prev->SystemID != NULL)) {
                if (!xmlStrEqual(ent->SystemID, prev->SystemID))
                    goto error;
            } else if ((ent->ExternalID != NULL) &&
                       (prev->ExternalID != NULL)) {
                if (!xmlStrEqual(ent->ExternalID, prev->ExternalID))
                    goto error;
            } else if ((ent->content != NULL) && (prev->content != NULL)) {
                if (!xmlStrEqual(ent->content, prev->content))
                    goto error;
            } else {
                goto error;
            }

        }
    }
    return;
error:
    switch (ent->etype) {
        case XML_INTERNAL_PARAMETER_ENTITY:
        case XML_EXTERNAL_PARAMETER_ENTITY:
        case XML_INTERNAL_PREDEFINED_ENTITY:
        case XML_INTERNAL_GENERAL_ENTITY:
        case XML_EXTERNAL_GENERAL_PARSED_ENTITY:
            return;
        case XML_EXTERNAL_GENERAL_UNPARSED_ENTITY:
            break;
    }
    xmlXIncludeErr(ctxt, (xmlNodePtr) ent, XML_XINCLUDE_ENTITY_DEF_MISMATCH,
                   "mismatch in redefinition of entity %s\n",
                   ent->name);
}

/**
 * xmlXIncludeMergeEntities:
 * @ctxt: an XInclude context
 * @doc:  the including doc
 * @from:  the included doc
 *
 * Inplements the entity merge
 *
 * Returns 0 if merge succeeded, -1 if some processing failed
 */
static int
xmlXIncludeMergeEntities(xmlXIncludeCtxtPtr ctxt, xmlDocPtr doc,
                         xmlDocPtr from) {
    xmlNodePtr cur;
    xmlDtdPtr target, source;

    if (ctxt == NULL)
        return(-1);

    if ((from == NULL) || (from->intSubset == NULL))
        return(0);

    target = doc->intSubset;
    if (target == NULL) {
        cur = xmlDocGetRootElement(doc);
        if (cur == NULL)
            return(-1);
        target = xmlCreateIntSubset(doc, cur->name, NULL, NULL);
        if (target == NULL)
            return(-1);
    }

    source = from->intSubset;
    if ((source != NULL) && (source->entities != NULL)) {
        xmlXIncludeMergeData data;

        data.ctxt = ctxt;
        data.doc = doc;

        xmlHashScan((xmlHashTablePtr) source->entities,
                    (xmlHashScanner) xmlXIncludeMergeEntity, &data);
    }
    source = from->extSubset;
    if ((source != NULL) && (source->entities != NULL)) {
        xmlXIncludeMergeData data;

        data.ctxt = ctxt;
        data.doc = doc;

        /*
         * don't duplicate existing stuff when external subsets are the same
         */
        if ((!xmlStrEqual(target->ExternalID, source->ExternalID)) &&
            (!xmlStrEqual(target->SystemID, source->SystemID))) {
            xmlHashScan((xmlHashTablePtr) source->entities,
                        (xmlHashScanner) xmlXIncludeMergeEntity, &data);
        }
    }
    return(0);
}

/**
 * xmlXIncludeLoadDoc:
 * @ctxt:  the XInclude context
 * @url:  the associated URL
 * @nr:  the xinclude node number
 * 
 * Load the document, and store the result in the XInclude context
 *
 * Returns 0 in case of success, -1 in case of failure
 */
static int
xmlXIncludeLoadDoc(xmlXIncludeCtxtPtr ctxt, const xmlChar *url, int nr) {
    xmlDocPtr doc;
    xmlURIPtr uri;
    xmlChar *URL;
    xmlChar *fragment = NULL;
    int i = 0;
#ifdef LIBXML_XPTR_ENABLED
    int saveFlags;
#endif

#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "Loading doc %s:%d\n", url, nr);
#endif
    /*
     * Check the URL and remove any fragment identifier
     */
    uri = xmlParseURI((const char *)url);
    if (uri == NULL) {
        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                       XML_XINCLUDE_HREF_URI,
                       "invalid value URI %s\n", url);
        return(-1);
    }
    if (uri->fragment != NULL) {
        fragment = (xmlChar *) uri->fragment;
        uri->fragment = NULL;
    }
    if ((ctxt->incTab != NULL) && (ctxt->incTab[nr] != NULL) &&
        (ctxt->incTab[nr]->fragment != NULL)) {
        if (fragment != NULL) xmlFree(fragment);
        fragment = xmlStrdup(ctxt->incTab[nr]->fragment);
    }
    URL = xmlSaveUri(uri);
    xmlFreeURI(uri);
    if (URL == NULL) {
        if (ctxt->incTab != NULL)
            xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                           XML_XINCLUDE_HREF_URI,
                           "invalid value URI %s\n", url);
        else
            xmlXIncludeErr(ctxt, NULL,
                           XML_XINCLUDE_HREF_URI,
                           "invalid value URI %s\n", url);
        if (fragment != NULL)
            xmlFree(fragment);
        return(-1);
    }

    /*
     * Handling of references to the local document are done
     * directly through ctxt->doc.
     */
    if ((URL[0] == 0) || (URL[0] == '#') ||
        ((ctxt->doc != NULL) && (xmlStrEqual(URL, ctxt->doc->URL)))) {
        doc = NULL;
        goto loaded;
    }

    /*
     * Prevent reloading twice the document.
     */
    for (i = 0; i < ctxt->incNr; i++) {
        if ((xmlStrEqual(URL, ctxt->incTab[i]->URI)) &&
            (ctxt->incTab[i]->doc != NULL)) {
            doc = ctxt->incTab[i]->doc;
#ifdef DEBUG_XINCLUDE
            printf("Already loaded %s\n", URL);
#endif
            goto loaded;
        }
    }

    /*
     * Load it.
     */
#ifdef DEBUG_XINCLUDE
    printf("loading %s\n", URL);
#endif
#ifdef LIBXML_XPTR_ENABLED
    /*
     * If this is an XPointer evaluation, we want to assure that
     * all entities have been resolved prior to processing the
     * referenced document
     */
    saveFlags = ctxt->parseFlags;
    if (fragment != NULL) {     /* if this is an XPointer eval */
        ctxt->parseFlags |= XML_PARSE_NOENT;
    }
#endif

    doc = xmlXIncludeParseFile(ctxt, (const char *)URL);
#ifdef LIBXML_XPTR_ENABLED
    ctxt->parseFlags = saveFlags;
#endif
    if (doc == NULL) {
        xmlFree(URL);
        if (fragment != NULL)
            xmlFree(fragment);
        return(-1);
    }
    ctxt->incTab[nr]->doc = doc;
    /*
     * It's possible that the requested URL has been mapped to a
     * completely different location (e.g. through a catalog entry).
     * To check for this, we compare the URL with that of the doc
     * and change it if they disagree (bug 146988).
     */
   if (!xmlStrEqual(URL, doc->URL)) {
       xmlFree(URL);
       URL = xmlStrdup(doc->URL);
   }
    for (i = nr + 1; i < ctxt->incNr; i++) {
        if (xmlStrEqual(URL, ctxt->incTab[i]->URI)) {
            ctxt->incTab[nr]->count++;
#ifdef DEBUG_XINCLUDE
            printf("Increasing %s count since reused\n", URL);
#endif
            break;
        }
    }

    /*
     * Make sure we have all entities fixed up
     */
    xmlXIncludeMergeEntities(ctxt, ctxt->doc, doc);

    /*
     * We don't need the DTD anymore, free up space
    if (doc->intSubset != NULL) {
        xmlUnlinkNode((xmlNodePtr) doc->intSubset);
        xmlFreeNode((xmlNodePtr) doc->intSubset);
        doc->intSubset = NULL;
    }
    if (doc->extSubset != NULL) {
        xmlUnlinkNode((xmlNodePtr) doc->extSubset);
        xmlFreeNode((xmlNodePtr) doc->extSubset);
        doc->extSubset = NULL;
    }
     */
    xmlXIncludeRecurseDoc(ctxt, doc, URL);

loaded:
    if (fragment == NULL) {
        /*
         * Add the top children list as the replacement copy.
         */
        if (doc == NULL)
        {
            /* Hopefully a DTD declaration won't be copied from
             * the same document */
            ctxt->incTab[nr]->inc = xmlCopyNodeList(ctxt->doc->children);
        } else {
            ctxt->incTab[nr]->inc = xmlXIncludeCopyNodeList(ctxt, ctxt->doc,
                                                       doc, doc->children);
        }
    } 
#ifdef LIBXML_XPTR_ENABLED
    else {
        /*
         * Computes the XPointer expression and make a copy used
         * as the replacement copy.
         */
        xmlXPathObjectPtr xptr;
        xmlXPathContextPtr xptrctxt;
        xmlNodeSetPtr set;

        if (doc == NULL) {
            xptrctxt = xmlXPtrNewContext(ctxt->doc, ctxt->incTab[nr]->ref,
                                         NULL);
        } else {
            xptrctxt = xmlXPtrNewContext(doc, NULL, NULL);
        }
        if (xptrctxt == NULL) {
            xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                           XML_XINCLUDE_XPTR_FAILED,
                           "could not create XPointer context\n", NULL);
            xmlFree(URL);
            xmlFree(fragment);
            return(-1);
        }
        xptr = xmlXPtrEval(fragment, xptrctxt);
        if (xptr == NULL) {
            xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
                           XML_XINCLUDE_XPTR_FAILED,
                           "XPointer evaluation failed: #%s\n",
                           fragment);
            xmlXPathFreeContext(xptrctxt);
            xmlFree(URL);
            xmlFree(fragment);
            return(-1);
        }
        switch (xptr->type) {
            case XPATH_UNDEFINED:
            case XPATH_BOOLEAN:
            case XPATH_NUMBER:
            case XPATH_STRING:
            case XPATH_POINT:
            case XPATH_USERS:
            case XPATH_XSLT_TREE:
                xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                               XML_XINCLUDE_XPTR_RESULT,
                               "XPointer is not a range: #%s\n",
                               fragment);
                xmlXPathFreeContext(xptrctxt);
                xmlFree(URL);
                xmlFree(fragment);
                return(-1);
            case XPATH_NODESET:
                if ((xptr->nodesetval == NULL) ||
                    (xptr->nodesetval->nodeNr <= 0)) {
                    xmlXPathFreeContext(xptrctxt);
                    xmlFree(URL);
                    xmlFree(fragment);
                    return(-1);
                }

            case XPATH_RANGE:
            case XPATH_LOCATIONSET:
                break;
        }
        set = xptr->nodesetval;
        if (set != NULL) {
            for (i = 0;i < set->nodeNr;i++) {
                if (set->nodeTab[i] == NULL)
                    continue;
                switch (set->nodeTab[i]->type) {
                    case XML_TEXT_NODE:
                    case XML_CDATA_SECTION_NODE:
                    case XML_ENTITY_REF_NODE:
                    case XML_ENTITY_NODE:
                    case XML_PI_NODE:
                    case XML_COMMENT_NODE:
                    case XML_DOCUMENT_NODE:
                    case XML_HTML_DOCUMENT_NODE:
#ifdef LIBXML_DOCB_ENABLED
                    case XML_DOCB_DOCUMENT_NODE:
#endif
                        continue;
                    case XML_ELEMENT_NODE: {
                        xmlChar *nodeBase;
                        xmlNodePtr el = set->nodeTab[i];

                        nodeBase = xmlNodeGetBase(el->doc, el);
                        if (nodeBase != NULL) {
                            if (!xmlStrEqual(nodeBase, el->doc->URL))
                                xmlNodeSetBase(el, nodeBase);
                            xmlFree(nodeBase);
                        }
                        continue;
                    }

                    case XML_ATTRIBUTE_NODE:
                        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                                       XML_XINCLUDE_XPTR_RESULT,
                                       "XPointer selects an attribute: #%s\n",
                                       fragment);
                        set->nodeTab[i] = NULL;
                        continue;
                    case XML_NAMESPACE_DECL:
                        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                                       XML_XINCLUDE_XPTR_RESULT,
                                       "XPointer selects a namespace: #%s\n",
                                       fragment);
                        set->nodeTab[i] = NULL;
                        continue;
                    case XML_DOCUMENT_TYPE_NODE:
                    case XML_DOCUMENT_FRAG_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:
                        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                                       XML_XINCLUDE_XPTR_RESULT,
                                   "XPointer selects unexpected nodes: #%s\n",
                                       fragment);
                        set->nodeTab[i] = NULL;
                        set->nodeTab[i] = NULL;
                        continue; /* for */
                }
            }
        }
        if (doc == NULL) {
            ctxt->incTab[nr]->xptr = xptr;
            ctxt->incTab[nr]->inc = NULL;
        } else {
            ctxt->incTab[nr]->inc =
                xmlXIncludeCopyXPointer(ctxt, ctxt->doc, doc, xptr);
            xmlXPathFreeObject(xptr);
        }
        xmlXPathFreeContext(xptrctxt);
        xmlFree(fragment);
    }
#endif

    /*
     * Do the xml:base fixup if needed
     */
    if ((doc != NULL) && (URL != NULL) && (xmlStrchr(URL, (xmlChar) '/'))) {
        xmlNodePtr node;
        xmlChar *base;
        xmlChar *curBase;

        /*
         * The base is only adjusted if "necessary", i.e. if the xinclude node
         * has a base specified, or the URL is relative
         */
        base = xmlGetNsProp(ctxt->incTab[nr]->ref, BAD_CAST "base",
                        XML_XML_NAMESPACE);
        if (base == NULL) {
            /*
             * No xml:base on the xinclude node, so we check whether the
             * URI base is different than (relative to) the context base
             */
            curBase = xmlBuildRelativeURI(URL, ctxt->base);
            if (curBase == NULL) {      /* Error return */
                xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                       XML_XINCLUDE_HREF_URI,
                       "trying to build relative URI from %s\n", URL);
            } else {
                /* If the URI doesn't contain a slash, it's not relative */
                if (!xmlStrchr(curBase, (xmlChar) '/'))
                    xmlFree(curBase);
                else
                    base = curBase;
            }
        }
        if (base != NULL) {     /* Adjustment may be needed */
            node = ctxt->incTab[nr]->inc;
            while (node != NULL) {
                /* Only work on element nodes */
                if (node->type == XML_ELEMENT_NODE) {
                    curBase = xmlNodeGetBase(node->doc, node);
                    /* If no current base, set it */
                    if (curBase == NULL) {
                        xmlNodeSetBase(node, base);
                    } else {
                        /*
                         * If the current base is the same as the
                         * URL of the document, then reset it to be
                         * the specified xml:base or the relative URI
                         */
                        if (xmlStrEqual(curBase, node->doc->URL)) {
                            xmlNodeSetBase(node, base);
                        } else {
                            /*
                             * If the element already has an xml:base
                             * set, then relativise it if necessary
                             */
                            xmlChar *xmlBase;
                            xmlBase = xmlGetNsProp(node,
                                            BAD_CAST "base",
                                            XML_XML_NAMESPACE);
                            if (xmlBase != NULL) {
                                xmlChar *relBase;
                                relBase = xmlBuildURI(xmlBase, base);
                                if (relBase == NULL) { /* error */
                                    xmlXIncludeErr(ctxt, 
                                                ctxt->incTab[nr]->ref,
                                                XML_XINCLUDE_HREF_URI,
                                        "trying to rebuild base from %s\n",
                                                xmlBase);
                                } else {
                                    xmlNodeSetBase(node, relBase);
                                    xmlFree(relBase);
                                }
                                xmlFree(xmlBase);
                            }
                        }
                        xmlFree(curBase);
                    }
                }
                node = node->next;
            }
            xmlFree(base);
        }
    }
    if ((nr < ctxt->incNr) && (ctxt->incTab[nr]->doc != NULL) &&
        (ctxt->incTab[nr]->count <= 1)) {
#ifdef DEBUG_XINCLUDE
        printf("freeing %s\n", ctxt->incTab[nr]->doc->URL);
#endif
        xmlFreeDoc(ctxt->incTab[nr]->doc);
        ctxt->incTab[nr]->doc = NULL;
    }
    xmlFree(URL);
    return(0);
}

/**
 * xmlXIncludeLoadTxt:
 * @ctxt:  the XInclude context
 * @url:  the associated URL
 * @nr:  the xinclude node number
 * 
 * Load the content, and store the result in the XInclude context
 *
 * Returns 0 in case of success, -1 in case of failure
 */
static int
xmlXIncludeLoadTxt(xmlXIncludeCtxtPtr ctxt, const xmlChar *url, int nr) {
    xmlParserInputBufferPtr buf;
    xmlNodePtr node;
    xmlURIPtr uri;
    xmlChar *URL;
    int i;
    xmlChar *encoding = NULL;
    xmlCharEncoding enc = (xmlCharEncoding) 0;

    /*
     * Check the URL and remove any fragment identifier
     */
    uri = xmlParseURI((const char *)url);
    if (uri == NULL) {
        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, XML_XINCLUDE_HREF_URI,
                       "invalid value URI %s\n", url);
        return(-1);
    }
    if (uri->fragment != NULL) {
        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, XML_XINCLUDE_TEXT_FRAGMENT,
                       "fragment identifier forbidden for text: %s\n",
                       (const xmlChar *) uri->fragment);
        xmlFreeURI(uri);
        return(-1);
    }
    URL = xmlSaveUri(uri);
    xmlFreeURI(uri);
    if (URL == NULL) {
        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, XML_XINCLUDE_HREF_URI,
                       "invalid value URI %s\n", url);
        return(-1);
    }

    /*
     * Handling of references to the local document are done
     * directly through ctxt->doc.
     */
    if (URL[0] == 0) {
        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                       XML_XINCLUDE_TEXT_DOCUMENT,
                       "text serialization of document not available\n", NULL);
        xmlFree(URL);
        return(-1);
    }

    /*
     * Prevent reloading twice the document.
     */
    for (i = 0; i < ctxt->txtNr; i++) {
        if (xmlStrEqual(URL, ctxt->txturlTab[i])) {
            node = xmlCopyNode(ctxt->txtTab[i], 1);
            goto loaded;
        }
    }
    /*
     * Try to get the encoding if available
     */
    if ((ctxt->incTab[nr] != NULL) && (ctxt->incTab[nr]->ref != NULL)) {
        encoding = xmlGetProp(ctxt->incTab[nr]->ref, XINCLUDE_PARSE_ENCODING);
    }
    if (encoding != NULL) {
        /*
         * TODO: we should not have to remap to the xmlCharEncoding
         *       predefined set, a better interface than
         *       xmlParserInputBufferCreateFilename should allow any
         *       encoding supported by iconv
         */
        enc = xmlParseCharEncoding((const char *) encoding);
        if (enc == XML_CHAR_ENCODING_ERROR) {
            xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
                           XML_XINCLUDE_UNKNOWN_ENCODING,
                           "encoding %s not supported\n", encoding);
            xmlFree(encoding);
            xmlFree(URL);
            return(-1);
        }
        xmlFree(encoding);
    }

    /*
     * Load it.
     */
    buf = xmlParserInputBufferCreateFilename((const char *)URL, enc);
    if (buf == NULL) {
        xmlFree(URL);
        return(-1);
    }
    node = xmlNewText(NULL);

    /*
     * Scan all chars from the resource and add the to the node
     */
    while (xmlParserInputBufferRead(buf, 128) > 0) {
        int len;
        const xmlChar *content;

        content = xmlBufferContent(buf->buffer);
        len = xmlBufferLength(buf->buffer);
        for (i = 0;i < len;) {
            int cur;
            int l;

            cur = xmlStringCurrentChar(NULL, &content[i], &l);
            if (!IS_CHAR(cur)) {
                xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
                               XML_XINCLUDE_INVALID_CHAR,
                               "%s contains invalid char\n", URL);
            } else {
                xmlNodeAddContentLen(node, &content[i], l);
            }
            i += l;
        }
        xmlBufferShrink(buf->buffer, len);
    }
    xmlFreeParserInputBuffer(buf);
    xmlXIncludeAddTxt(ctxt, node, URL);

loaded:
    /*
     * Add the element as the replacement copy.
     */
    ctxt->incTab[nr]->inc = node;
    xmlFree(URL);
    return(0);
}

/**
 * xmlXIncludeLoadFallback:
 * @ctxt:  the XInclude context
 * @fallback:  the fallback node
 * @nr:  the xinclude node number
 * 
 * Load the content of the fallback node, and store the result
 * in the XInclude context
 *
 * Returns 0 in case of success, -1 in case of failure
 */
static int
xmlXIncludeLoadFallback(xmlXIncludeCtxtPtr ctxt, xmlNodePtr fallback, int nr) {
    xmlXIncludeCtxtPtr newctxt;
    int ret = 0;
    
    if ((fallback == NULL) || (ctxt == NULL))
        return(-1);
    if (fallback->children != NULL) {
        /*
         * It's possible that the fallback also has 'includes'
         * (Bug 129969), so we re-process the fallback just in case
         */
        newctxt = xmlXIncludeNewContext(ctxt->doc);
        if (newctxt == NULL)
            return (-1);
        newctxt->base = xmlStrdup(ctxt->base);  /* Inherit the base from the existing context */
        xmlXIncludeSetFlags(newctxt, ctxt->parseFlags);
        ret = xmlXIncludeDoProcess(newctxt, ctxt->doc, fallback->children);
        if (ctxt->nbErrors > 0)
            ret = -1;
        else if (ret > 0)
            ret = 0;    /* xmlXIncludeDoProcess can return +ve number */
        xmlXIncludeFreeContext(newctxt);

        ctxt->incTab[nr]->inc = xmlDocCopyNodeList(ctxt->doc,
                                                   fallback->children);
    } else {
        ctxt->incTab[nr]->inc = NULL;
        ctxt->incTab[nr]->emptyFb = 1;  /* flag empty callback */
    }
    return(ret);
}

/************************************************************************
 *                                                                      *
 *                      XInclude Processing                             *
 *                                                                      *
 ************************************************************************/

/**
 * xmlXIncludePreProcessNode:
 * @ctxt: an XInclude context
 * @node: an XInclude node
 *
 * Implement the XInclude preprocessing, currently just adding the element
 * for further processing.
 *
 * Returns the result list or NULL in case of error
 */
static xmlNodePtr
xmlXIncludePreProcessNode(xmlXIncludeCtxtPtr ctxt, xmlNodePtr node) {
    xmlXIncludeAddNode(ctxt, node);
    return(NULL);
}

/**
 * xmlXIncludeLoadNode:
 * @ctxt: an XInclude context
 * @nr: the node number
 *
 * Find and load the infoset replacement for the given node.
 *
 * Returns 0 if substitution succeeded, -1 if some processing failed
 */
static int
xmlXIncludeLoadNode(xmlXIncludeCtxtPtr ctxt, int nr) {
    xmlNodePtr cur;
    xmlChar *href;
    xmlChar *parse;
    xmlChar *base;
    xmlChar *oldBase;
    xmlChar *URI;
    int xml = 1; /* default Issue 64 */
    int ret;

    if (ctxt == NULL)
        return(-1);
    if ((nr < 0) || (nr >= ctxt->incNr))
        return(-1);
    cur = ctxt->incTab[nr]->ref;
    if (cur == NULL)
        return(-1);

    /*
     * read the attributes
     */
    href = xmlXIncludeGetProp(ctxt, cur, XINCLUDE_HREF);
    if (href == NULL) {
        href = xmlStrdup(BAD_CAST ""); /* @@@@ href is now optional */
        if (href == NULL) 
            return(-1);
    }
    parse = xmlXIncludeGetProp(ctxt, cur, XINCLUDE_PARSE);
    if (parse != NULL) {
        if (xmlStrEqual(parse, XINCLUDE_PARSE_XML))
            xml = 1;
        else if (xmlStrEqual(parse, XINCLUDE_PARSE_TEXT))
            xml = 0;
        else {
            xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
                           XML_XINCLUDE_PARSE_VALUE,
                           "invalid value %s for 'parse'\n", parse);
            if (href != NULL)
                xmlFree(href);
            if (parse != NULL)
                xmlFree(parse);
            return(-1);
        }
    }

    /*
     * compute the URI
     */
    base = xmlNodeGetBase(ctxt->doc, cur);
    if (base == NULL) {
        URI = xmlBuildURI(href, ctxt->doc->URL);
    } else {
        URI = xmlBuildURI(href, base);
    }
    if (URI == NULL) {
        xmlChar *escbase;
        xmlChar *eschref;
        /*
         * Some escaping may be needed
         */
        escbase = xmlURIEscape(base);
        eschref = xmlURIEscape(href);
        URI = xmlBuildURI(eschref, escbase);
        if (escbase != NULL)
            xmlFree(escbase);
        if (eschref != NULL)
            xmlFree(eschref);
    }
    if (URI == NULL) {
        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                       XML_XINCLUDE_HREF_URI, "failed build URL\n", NULL);
        if (parse != NULL)
            xmlFree(parse);
        if (href != NULL)
            xmlFree(href);
        if (base != NULL)
            xmlFree(base);
        return(-1);
    }
#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "parse: %s\n",
            xml ? "xml": "text");
    xmlGenericError(xmlGenericErrorContext, "URI: %s\n", URI);
#endif

    /*
     * Save the base for this include (saving the current one)
     */
    oldBase = ctxt->base;
    ctxt->base = base;

    if (xml) {
        ret = xmlXIncludeLoadDoc(ctxt, URI, nr);
        /* xmlXIncludeGetFragment(ctxt, cur, URI); */
    } else {
        ret = xmlXIncludeLoadTxt(ctxt, URI, nr);
    }

    /*
     * Restore the original base before checking for fallback
     */
    ctxt->base = oldBase;
    
    if (ret < 0) {
        xmlNodePtr children;

        /*
         * Time to try a fallback if availble
         */
#ifdef DEBUG_XINCLUDE
        xmlGenericError(xmlGenericErrorContext, "error looking for fallback\n");
#endif
        children = cur->children;
        while (children != NULL) {
            if ((children->type == XML_ELEMENT_NODE) &&
                (children->ns != NULL) &&
                (xmlStrEqual(children->name, XINCLUDE_FALLBACK)) &&
                ((xmlStrEqual(children->ns->href, XINCLUDE_NS)) ||
                 (xmlStrEqual(children->ns->href, XINCLUDE_OLD_NS)))) {
                ret = xmlXIncludeLoadFallback(ctxt, children, nr);
                if (ret == 0) 
                    break;
            }
            children = children->next;
        }
    }
    if (ret < 0) {
        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                       XML_XINCLUDE_NO_FALLBACK,
                       "could not load %s, and no fallback was found\n",
                       URI);
    }

    /*
     * Cleanup
     */
    if (URI != NULL)
        xmlFree(URI);
    if (parse != NULL)
        xmlFree(parse);
    if (href != NULL)
        xmlFree(href);
    if (base != NULL)
        xmlFree(base);
    return(0);
}

/**
 * xmlXIncludeIncludeNode:
 * @ctxt: an XInclude context
 * @nr: the node number
 *
 * Inplement the infoset replacement for the given node
 *
 * Returns 0 if substitution succeeded, -1 if some processing failed
 */
static int
xmlXIncludeIncludeNode(xmlXIncludeCtxtPtr ctxt, int nr) {
    xmlNodePtr cur, end, list, tmp;

    if (ctxt == NULL)
        return(-1);
    if ((nr < 0) || (nr >= ctxt->incNr))
        return(-1);
    cur = ctxt->incTab[nr]->ref;
    if (cur == NULL)
        return(-1);

    /*
     * If we stored an XPointer a late computation may be needed
     */
    if ((ctxt->incTab[nr]->inc == NULL) &&
        (ctxt->incTab[nr]->xptr != NULL)) {
        ctxt->incTab[nr]->inc =
            xmlXIncludeCopyXPointer(ctxt, ctxt->doc, ctxt->doc,
                                    ctxt->incTab[nr]->xptr);
        xmlXPathFreeObject(ctxt->incTab[nr]->xptr);
        ctxt->incTab[nr]->xptr = NULL;
    }
    list = ctxt->incTab[nr]->inc;
    ctxt->incTab[nr]->inc = NULL;

    /*
     * Check against the risk of generating a multi-rooted document
     */
    if ((cur->parent != NULL) &&
        (cur->parent->type != XML_ELEMENT_NODE)) {
        int nb_elem = 0;

        tmp = list;
        while (tmp != NULL) {
            if (tmp->type == XML_ELEMENT_NODE)
                nb_elem++;
            tmp = tmp->next;
        }
        if (nb_elem > 1) {
            xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
                           XML_XINCLUDE_MULTIPLE_ROOT,
                       "XInclude error: would result in multiple root nodes\n",
                           NULL);
            return(-1);
        }
    }

    if (ctxt->parseFlags & XML_PARSE_NOXINCNODE) {
        /*
         * Add the list of nodes
         */
        while (list != NULL) {
            end = list;
            list = list->next;

            xmlAddPrevSibling(cur, end);
        }
        xmlUnlinkNode(cur);
        xmlFreeNode(cur);
    } else {
        /*
         * Change the current node as an XInclude start one, and add an
         * XInclude end one
         */
        cur->type = XML_XINCLUDE_START;
        end = xmlNewDocNode(cur->doc, cur->ns, cur->name, NULL);
        if (end == NULL) {
            xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
                           XML_XINCLUDE_BUILD_FAILED,
                           "failed to build node\n", NULL);
            return(-1);
        }
        end->type = XML_XINCLUDE_END;
        xmlAddNextSibling(cur, end);

        /*
         * Add the list of nodes
         */
        while (list != NULL) {
            cur = list;
            list = list->next;

            xmlAddPrevSibling(end, cur);
        }
    }

    
    return(0);
}

/**
 * xmlXIncludeTestNode:
 * @ctxt: the XInclude processing context
 * @node: an XInclude node
 *
 * test if the node is an XInclude node
 *
 * Returns 1 true, 0 otherwise
 */
static int
xmlXIncludeTestNode(xmlXIncludeCtxtPtr ctxt, xmlNodePtr node) {
    if (node == NULL)
        return(0);
    if (node->type != XML_ELEMENT_NODE)
        return(0);
    if (node->ns == NULL)
        return(0);
    if ((xmlStrEqual(node->ns->href, XINCLUDE_NS)) ||
        (xmlStrEqual(node->ns->href, XINCLUDE_OLD_NS))) {
        if (xmlStrEqual(node->ns->href, XINCLUDE_OLD_NS)) {
            if (ctxt->legacy == 0) {
#if 0 /* wait for the XML Core Working Group to get something stable ! */
                xmlXIncludeWarn(ctxt, node, XML_XINCLUDE_DEPRECATED_NS,
                       "Deprecated XInclude namespace found, use %s",
                                XINCLUDE_NS);
#endif
                ctxt->legacy = 1;
            }
        }
        if (xmlStrEqual(node->name, XINCLUDE_NODE)) {
            xmlNodePtr child = node->children;
            int nb_fallback = 0;

            while (child != NULL) {
                if ((child->type == XML_ELEMENT_NODE) &&
                    (child->ns != NULL) &&
                    ((xmlStrEqual(child->ns->href, XINCLUDE_NS)) ||
                     (xmlStrEqual(child->ns->href, XINCLUDE_OLD_NS)))) {
                    if (xmlStrEqual(child->name, XINCLUDE_NODE)) {
                        xmlXIncludeErr(ctxt, node,
                                       XML_XINCLUDE_INCLUDE_IN_INCLUDE,
                                       "%s has an 'include' child\n",
                                       XINCLUDE_NODE);
                        return(0);
                    }
                    if (xmlStrEqual(child->name, XINCLUDE_FALLBACK)) {
                        nb_fallback++;
                    }
                }
                child = child->next;
            }
            if (nb_fallback > 1) {
                xmlXIncludeErr(ctxt, node, XML_XINCLUDE_FALLBACKS_IN_INCLUDE,
                               "%s has multiple fallback children\n",
                               XINCLUDE_NODE);
                return(0);
            }
            return(1);
        }
        if (xmlStrEqual(node->name, XINCLUDE_FALLBACK)) {
            if ((node->parent == NULL) ||
                (node->parent->type != XML_ELEMENT_NODE) ||
                (node->parent->ns == NULL) ||
                ((!xmlStrEqual(node->parent->ns->href, XINCLUDE_NS)) &&
                 (!xmlStrEqual(node->parent->ns->href, XINCLUDE_OLD_NS))) ||
                (!xmlStrEqual(node->parent->name, XINCLUDE_NODE))) {
                xmlXIncludeErr(ctxt, node,
                               XML_XINCLUDE_FALLBACK_NOT_IN_INCLUDE,
                               "%s is not the child of an 'include'\n",
                               XINCLUDE_FALLBACK);
            }
        }
    }
    return(0);
}

/**
 * xmlXIncludeDoProcess:
 * @ctxt: the XInclude processing context
 * @doc: an XML document
 * @tree: the top of the tree to process
 *
 * Implement the XInclude substitution on the XML document @doc
 *
 * Returns 0 if no substitution were done, -1 if some processing failed
 *    or the number of substitutions done.
 */
static int
xmlXIncludeDoProcess(xmlXIncludeCtxtPtr ctxt, xmlDocPtr doc, xmlNodePtr tree) {
    xmlNodePtr cur;
    int ret = 0;
    int i, start;

    if ((doc == NULL) || (tree == NULL))
        return(-1);
    if (ctxt == NULL)
        return(-1);

    if (doc->URL != NULL) {
        ret = xmlXIncludeURLPush(ctxt, doc->URL);
        if (ret < 0)
            return(-1);
    }
    start = ctxt->incNr;

    /*
     * First phase: lookup the elements in the document
     */
    cur = tree;
    if (xmlXIncludeTestNode(ctxt, cur) == 1)
        xmlXIncludePreProcessNode(ctxt, cur);
    while ((cur != NULL) && (cur != tree->parent)) {
        /* TODO: need to work on entities -> stack */
        if ((cur->children != NULL) &&
            (cur->children->type != XML_ENTITY_DECL) &&
            (cur->children->type != XML_XINCLUDE_START) &&
            (cur->children->type != XML_XINCLUDE_END)) {
            cur = cur->children;
            if (xmlXIncludeTestNode(ctxt, cur))
                xmlXIncludePreProcessNode(ctxt, cur);
        } else if (cur->next != NULL) {
            cur = cur->next;
            if (xmlXIncludeTestNode(ctxt, cur))
                xmlXIncludePreProcessNode(ctxt, cur);
        } else {
            if (cur == tree)
                break;
            do {
                cur = cur->parent;
                if ((cur == NULL) || (cur == tree->parent))
                    break; /* do */
                if (cur->next != NULL) {
                    cur = cur->next;
                    if (xmlXIncludeTestNode(ctxt, cur))
                        xmlXIncludePreProcessNode(ctxt, cur);
                    break; /* do */
                }
            } while (cur != NULL);
        }
    }

    /*
     * Second Phase : collect the infosets fragments
     */
    for (i = start;i < ctxt->incNr; i++) {
        xmlXIncludeLoadNode(ctxt, i);
        ret++;
    }

    /*
     * Third phase: extend the original document infoset.
     *
     * Originally we bypassed the inclusion if there were any errors
     * encountered on any of the XIncludes.  A bug was raised (bug
     * 132588) requesting that we output the XIncludes without error,
     * so the check for inc!=NULL || xptr!=NULL was put in.  This may
     * give some other problems in the future, but for now it seems to
     * work ok.
     *
     */
    for (i = ctxt->incBase;i < ctxt->incNr; i++) {
        if ((ctxt->incTab[i]->inc != NULL) ||
                (ctxt->incTab[i]->xptr != NULL) ||
                (ctxt->incTab[i]->emptyFb != 0))        /* (empty fallback) */
            xmlXIncludeIncludeNode(ctxt, i);
    }

    if (doc->URL != NULL)
        xmlXIncludeURLPop(ctxt);
    return(ret);
}

/**
 * xmlXIncludeSetFlags:
 * @ctxt:  an XInclude processing context
 * @flags: a set of xmlParserOption used for parsing XML includes
 *
 * Set the flags used for further processing of XML resources.
 *
 * Returns 0 in case of success and -1 in case of error.
 */
int
xmlXIncludeSetFlags(xmlXIncludeCtxtPtr ctxt, int flags) {
    if (ctxt == NULL)
        return(-1);
    ctxt->parseFlags = flags;
    return(0);
}
 
/**
 * xmlXIncludeProcessFlagsData:
 * @doc: an XML document
 * @flags: a set of xmlParserOption used for parsing XML includes
 * @data: application data that will be passed to the parser context
 *        in the _private field of the parser context(s)
 *
 * Implement the XInclude substitution on the XML document @doc
 *
 * Returns 0 if no substitution were done, -1 if some processing failed
 *    or the number of substitutions done.
 */
int
xmlXIncludeProcessFlagsData(xmlDocPtr doc, int flags, void *data) {
    xmlXIncludeCtxtPtr ctxt;
    xmlNodePtr tree;
    int ret = 0;

    if (doc == NULL)
        return(-1);
    tree = xmlDocGetRootElement(doc);
    if (tree == NULL)
        return(-1);
    ctxt = xmlXIncludeNewContext(doc);
    if (ctxt == NULL)
        return(-1);
    ctxt->_private = data;
    ctxt->base = xmlStrdup((xmlChar *)doc->URL);
    xmlXIncludeSetFlags(ctxt, flags);
    ret = xmlXIncludeDoProcess(ctxt, doc, tree);
    if ((ret >= 0) && (ctxt->nbErrors > 0))
        ret = -1;

    xmlXIncludeFreeContext(ctxt);
    return(ret);
}

/**
 * xmlXIncludeProcessFlags:
 * @doc: an XML document
 * @flags: a set of xmlParserOption used for parsing XML includes
 *
 * Implement the XInclude substitution on the XML document @doc
 *
 * Returns 0 if no substitution were done, -1 if some processing failed
 *    or the number of substitutions done.
 */
int
xmlXIncludeProcessFlags(xmlDocPtr doc, int flags) {
    return xmlXIncludeProcessFlagsData(doc, flags, NULL);
}

/**
 * xmlXIncludeProcess:
 * @doc: an XML document
 *
 * Implement the XInclude substitution on the XML document @doc
 *
 * Returns 0 if no substitution were done, -1 if some processing failed
 *    or the number of substitutions done.
 */
int
xmlXIncludeProcess(xmlDocPtr doc) {
    return(xmlXIncludeProcessFlags(doc, 0));
}

/**
 * xmlXIncludeProcessTreeFlags:
 * @tree: a node in an XML document
 * @flags: a set of xmlParserOption used for parsing XML includes
 *
 * Implement the XInclude substitution for the given subtree
 *
 * Returns 0 if no substitution were done, -1 if some processing failed
 *    or the number of substitutions done.
 */
int
xmlXIncludeProcessTreeFlags(xmlNodePtr tree, int flags) {
    xmlXIncludeCtxtPtr ctxt;
    int ret = 0;

    if ((tree == NULL) || (tree->doc == NULL))
        return(-1);
    ctxt = xmlXIncludeNewContext(tree->doc);
    if (ctxt == NULL)
        return(-1);
    ctxt->base = xmlNodeGetBase(tree->doc, tree);
    xmlXIncludeSetFlags(ctxt, flags);
    ret = xmlXIncludeDoProcess(ctxt, tree->doc, tree);
    if ((ret >= 0) && (ctxt->nbErrors > 0))
        ret = -1;

    xmlXIncludeFreeContext(ctxt);
    return(ret);
}

/**
 * xmlXIncludeProcessTree:
 * @tree: a node in an XML document
 *
 * Implement the XInclude substitution for the given subtree
 *
 * Returns 0 if no substitution were done, -1 if some processing failed
 *    or the number of substitutions done.
 */
int
xmlXIncludeProcessTree(xmlNodePtr tree) {
    return(xmlXIncludeProcessTreeFlags(tree, 0));
}

/**
 * xmlXIncludeProcessNode:
 * @ctxt: an existing XInclude context
 * @node: a node in an XML document
 *
 * Implement the XInclude substitution for the given subtree reusing
 * the informations and data coming from the given context.
 *
 * Returns 0 if no substitution were done, -1 if some processing failed
 *    or the number of substitutions done.
 */
int
xmlXIncludeProcessNode(xmlXIncludeCtxtPtr ctxt, xmlNodePtr node) {
    int ret = 0;

    if ((node == NULL) || (node->doc == NULL) || (ctxt == NULL))
        return(-1);
    ret = xmlXIncludeDoProcess(ctxt, node->doc, node);
    if ((ret >= 0) && (ctxt->nbErrors > 0))
        ret = -1;
    return(ret);
}

#else /* !LIBXML_XINCLUDE_ENABLED */
#endif
#define bottom_xinclude
#include "elfgcchack.h"
