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kc3-lang/libxml2/pattern.c

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  • Author : Jared Yanovich
    Date : 2019-09-30 17:04:54
    Hash : 2a350ee9
    Message : Large batch of typo fixes Closes #109.

  • pattern.c
  • /*
     * pattern.c: Implementation of selectors for nodes
     *
     * Reference:
     *   http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/
     *   to some extent
     *   http://www.w3.org/TR/1999/REC-xml-19991116
     *
     * See Copyright for the status of this software.
     *
     * daniel@veillard.com
     */
    
    /*
     * TODO:
     * - compilation flags to check for specific syntaxes
     *   using flags of xmlPatterncompile()
     * - making clear how pattern starting with / or . need to be handled,
     *   currently push(NULL, NULL) means a reset of the streaming context
     *   and indicating we are on / (the document node), probably need
     *   something similar for .
     * - get rid of the "compile" starting with lowercase
     * - DONE (2006-05-16): get rid of the Strdup/Strndup in case of dictionary
     */
    
    #define IN_LIBXML
    #include "libxml.h"
    
    #include <string.h>
    #include <libxml/xmlmemory.h>
    #include <libxml/tree.h>
    #include <libxml/hash.h>
    #include <libxml/dict.h>
    #include <libxml/xmlerror.h>
    #include <libxml/parserInternals.h>
    #include <libxml/pattern.h>
    
    #ifdef LIBXML_PATTERN_ENABLED
    
    /* #define DEBUG_STREAMING */
    
    #ifdef ERROR
    #undef ERROR
    #endif
    #define ERROR(a, b, c, d)
    #define ERROR5(a, b, c, d, e)
    
    #define XML_STREAM_STEP_DESC	1
    #define XML_STREAM_STEP_FINAL	2
    #define XML_STREAM_STEP_ROOT	4
    #define XML_STREAM_STEP_ATTR	8
    #define XML_STREAM_STEP_NODE	16
    #define XML_STREAM_STEP_IN_SET	32
    
    /*
    * NOTE: Those private flags (XML_STREAM_xxx) are used
    *   in _xmlStreamCtxt->flag. They extend the public
    *   xmlPatternFlags, so be careful not to interfere with the
    *   reserved values for xmlPatternFlags.
    */
    #define XML_STREAM_FINAL_IS_ANY_NODE 1<<14
    #define XML_STREAM_FROM_ROOT 1<<15
    #define XML_STREAM_DESC 1<<16
    
    /*
    * XML_STREAM_ANY_NODE is used for comparison against
    * xmlElementType enums, to indicate a node of any type.
    */
    #define XML_STREAM_ANY_NODE 100
    
    #define XML_PATTERN_NOTPATTERN  (XML_PATTERN_XPATH | \
    				 XML_PATTERN_XSSEL | \
    				 XML_PATTERN_XSFIELD)
    
    #define XML_STREAM_XS_IDC(c) ((c)->flags & \
        (XML_PATTERN_XSSEL | XML_PATTERN_XSFIELD))
    
    #define XML_STREAM_XS_IDC_SEL(c) ((c)->flags & XML_PATTERN_XSSEL)
    
    #define XML_STREAM_XS_IDC_FIELD(c) ((c)->flags & XML_PATTERN_XSFIELD)
    
    #define XML_PAT_COPY_NSNAME(c, r, nsname) \
        if ((c)->comp->dict) \
    	r = (xmlChar *) xmlDictLookup((c)->comp->dict, BAD_CAST nsname, -1); \
        else r = xmlStrdup(BAD_CAST nsname);
    
    #define XML_PAT_FREE_STRING(c, r) if ((c)->comp->dict == NULL) xmlFree(r);
    
    typedef struct _xmlStreamStep xmlStreamStep;
    typedef xmlStreamStep *xmlStreamStepPtr;
    struct _xmlStreamStep {
        int flags;			/* properties of that step */
        const xmlChar *name;	/* first string value if NULL accept all */
        const xmlChar *ns;		/* second string value */
        int nodeType;		/* type of node */
    };
    
    typedef struct _xmlStreamComp xmlStreamComp;
    typedef xmlStreamComp *xmlStreamCompPtr;
    struct _xmlStreamComp {
        xmlDict *dict;		/* the dictionary if any */
        int nbStep;			/* number of steps in the automata */
        int maxStep;		/* allocated number of steps */
        xmlStreamStepPtr steps;	/* the array of steps */
        int flags;
    };
    
    struct _xmlStreamCtxt {
        struct _xmlStreamCtxt *next;/* link to next sub pattern if | */
        xmlStreamCompPtr comp;	/* the compiled stream */
        int nbState;		/* number of states in the automata */
        int maxState;		/* allocated number of states */
        int level;			/* how deep are we ? */
        int *states;		/* the array of step indexes */
        int flags;			/* validation options */
        int blockLevel;
    };
    
    static void xmlFreeStreamComp(xmlStreamCompPtr comp);
    
    /*
     * Types are private:
     */
    
    typedef enum {
        XML_OP_END=0,
        XML_OP_ROOT,
        XML_OP_ELEM,
        XML_OP_CHILD,
        XML_OP_ATTR,
        XML_OP_PARENT,
        XML_OP_ANCESTOR,
        XML_OP_NS,
        XML_OP_ALL
    } xmlPatOp;
    
    
    typedef struct _xmlStepState xmlStepState;
    typedef xmlStepState *xmlStepStatePtr;
    struct _xmlStepState {
        int step;
        xmlNodePtr node;
    };
    
    typedef struct _xmlStepStates xmlStepStates;
    typedef xmlStepStates *xmlStepStatesPtr;
    struct _xmlStepStates {
        int nbstates;
        int maxstates;
        xmlStepStatePtr states;
    };
    
    typedef struct _xmlStepOp xmlStepOp;
    typedef xmlStepOp *xmlStepOpPtr;
    struct _xmlStepOp {
        xmlPatOp op;
        const xmlChar *value;
        const xmlChar *value2; /* The namespace name */
    };
    
    #define PAT_FROM_ROOT	(1<<8)
    #define PAT_FROM_CUR	(1<<9)
    
    struct _xmlPattern {
        void *data;		/* the associated template */
        xmlDictPtr dict;		/* the optional dictionary */
        struct _xmlPattern *next;	/* next pattern if | is used */
        const xmlChar *pattern;	/* the pattern */
        int flags;			/* flags */
        int nbStep;
        int maxStep;
        xmlStepOpPtr steps;        /* ops for computation */
        xmlStreamCompPtr stream;	/* the streaming data if any */
    };
    
    typedef struct _xmlPatParserContext xmlPatParserContext;
    typedef xmlPatParserContext *xmlPatParserContextPtr;
    struct _xmlPatParserContext {
        const xmlChar *cur;			/* the current char being parsed */
        const xmlChar *base;		/* the full expression */
        int	           error;		/* error code */
        xmlDictPtr     dict;		/* the dictionary if any */
        xmlPatternPtr  comp;		/* the result */
        xmlNodePtr     elem;		/* the current node if any */
        const xmlChar **namespaces;		/* the namespaces definitions */
        int   nb_namespaces;		/* the number of namespaces */
    };
    
    /************************************************************************
     *									*
     *			Type functions					*
     *									*
     ************************************************************************/
    
    /**
     * xmlNewPattern:
     *
     * Create a new XSLT Pattern
     *
     * Returns the newly allocated xmlPatternPtr or NULL in case of error
     */
    static xmlPatternPtr
    xmlNewPattern(void) {
        xmlPatternPtr cur;
    
        cur = (xmlPatternPtr) xmlMalloc(sizeof(xmlPattern));
        if (cur == NULL) {
    	ERROR(NULL, NULL, NULL,
    		"xmlNewPattern : malloc failed\n");
    	return(NULL);
        }
        memset(cur, 0, sizeof(xmlPattern));
        cur->maxStep = 10;
        cur->steps = (xmlStepOpPtr) xmlMalloc(cur->maxStep * sizeof(xmlStepOp));
        if (cur->steps == NULL) {
            xmlFree(cur);
    	ERROR(NULL, NULL, NULL,
    		"xmlNewPattern : malloc failed\n");
    	return(NULL);
        }
        return(cur);
    }
    
    /**
     * xmlFreePattern:
     * @comp:  an XSLT comp
     *
     * Free up the memory allocated by @comp
     */
    void
    xmlFreePattern(xmlPatternPtr comp) {
        xmlFreePatternList(comp);
    }
    
    static void
    xmlFreePatternInternal(xmlPatternPtr comp) {
        xmlStepOpPtr op;
        int i;
    
        if (comp == NULL)
    	return;
        if (comp->stream != NULL)
            xmlFreeStreamComp(comp->stream);
        if (comp->pattern != NULL)
    	xmlFree((xmlChar *)comp->pattern);
        if (comp->steps != NULL) {
            if (comp->dict == NULL) {
    	    for (i = 0;i < comp->nbStep;i++) {
    		op = &comp->steps[i];
    		if (op->value != NULL)
    		    xmlFree((xmlChar *) op->value);
    		if (op->value2 != NULL)
    		    xmlFree((xmlChar *) op->value2);
    	    }
    	}
    	xmlFree(comp->steps);
        }
        if (comp->dict != NULL)
            xmlDictFree(comp->dict);
    
        memset(comp, -1, sizeof(xmlPattern));
        xmlFree(comp);
    }
    
    /**
     * xmlFreePatternList:
     * @comp:  an XSLT comp list
     *
     * Free up the memory allocated by all the elements of @comp
     */
    void
    xmlFreePatternList(xmlPatternPtr comp) {
        xmlPatternPtr cur;
    
        while (comp != NULL) {
    	cur = comp;
    	comp = comp->next;
    	cur->next = NULL;
    	xmlFreePatternInternal(cur);
        }
    }
    
    /**
     * xmlNewPatParserContext:
     * @pattern:  the pattern context
     * @dict:  the inherited dictionary or NULL
     * @namespaces: the prefix definitions, array of [URI, prefix] terminated
     *              with [NULL, NULL] or NULL if no namespace is used
     *
     * Create a new XML pattern parser context
     *
     * Returns the newly allocated xmlPatParserContextPtr or NULL in case of error
     */
    static xmlPatParserContextPtr
    xmlNewPatParserContext(const xmlChar *pattern, xmlDictPtr dict,
                           const xmlChar **namespaces) {
        xmlPatParserContextPtr cur;
    
        if (pattern == NULL)
            return(NULL);
    
        cur = (xmlPatParserContextPtr) xmlMalloc(sizeof(xmlPatParserContext));
        if (cur == NULL) {
    	ERROR(NULL, NULL, NULL,
    		"xmlNewPatParserContext : malloc failed\n");
    	return(NULL);
        }
        memset(cur, 0, sizeof(xmlPatParserContext));
        cur->dict = dict;
        cur->cur = pattern;
        cur->base = pattern;
        if (namespaces != NULL) {
            int i;
            for (i = 0;namespaces[2 * i] != NULL;i++)
                ;
            cur->nb_namespaces = i;
        } else {
            cur->nb_namespaces = 0;
        }
        cur->namespaces = namespaces;
        return(cur);
    }
    
    /**
     * xmlFreePatParserContext:
     * @ctxt:  an XSLT parser context
     *
     * Free up the memory allocated by @ctxt
     */
    static void
    xmlFreePatParserContext(xmlPatParserContextPtr ctxt) {
        if (ctxt == NULL)
    	return;
        memset(ctxt, -1, sizeof(xmlPatParserContext));
        xmlFree(ctxt);
    }
    
    /**
     * xmlPatternAdd:
     * @comp:  the compiled match expression
     * @op:  an op
     * @value:  the first value
     * @value2:  the second value
     *
     * Add a step to an XSLT Compiled Match
     *
     * Returns -1 in case of failure, 0 otherwise.
     */
    static int
    xmlPatternAdd(xmlPatParserContextPtr ctxt ATTRIBUTE_UNUSED,
                    xmlPatternPtr comp,
                    xmlPatOp op, xmlChar * value, xmlChar * value2)
    {
        if (comp->nbStep >= comp->maxStep) {
            xmlStepOpPtr temp;
    	temp = (xmlStepOpPtr) xmlRealloc(comp->steps, comp->maxStep * 2 *
    	                                 sizeof(xmlStepOp));
            if (temp == NULL) {
    	    ERROR(ctxt, NULL, NULL,
    			     "xmlPatternAdd: realloc failed\n");
    	    return (-1);
    	}
    	comp->steps = temp;
    	comp->maxStep *= 2;
        }
        comp->steps[comp->nbStep].op = op;
        comp->steps[comp->nbStep].value = value;
        comp->steps[comp->nbStep].value2 = value2;
        comp->nbStep++;
        return (0);
    }
    
    #if 0
    /**
     * xsltSwapTopPattern:
     * @comp:  the compiled match expression
     *
     * reverse the two top steps.
     */
    static void
    xsltSwapTopPattern(xmlPatternPtr comp) {
        int i;
        int j = comp->nbStep - 1;
    
        if (j > 0) {
    	register const xmlChar *tmp;
    	register xmlPatOp op;
    	i = j - 1;
    	tmp = comp->steps[i].value;
    	comp->steps[i].value = comp->steps[j].value;
    	comp->steps[j].value = tmp;
    	tmp = comp->steps[i].value2;
    	comp->steps[i].value2 = comp->steps[j].value2;
    	comp->steps[j].value2 = tmp;
    	op = comp->steps[i].op;
    	comp->steps[i].op = comp->steps[j].op;
    	comp->steps[j].op = op;
        }
    }
    #endif
    
    /**
     * xmlReversePattern:
     * @comp:  the compiled match expression
     *
     * reverse all the stack of expressions
     *
     * returns 0 in case of success and -1 in case of error.
     */
    static int
    xmlReversePattern(xmlPatternPtr comp) {
        int i, j;
    
        /*
         * remove the leading // for //a or .//a
         */
        if ((comp->nbStep > 0) && (comp->steps[0].op == XML_OP_ANCESTOR)) {
            for (i = 0, j = 1;j < comp->nbStep;i++,j++) {
    	    comp->steps[i].value = comp->steps[j].value;
    	    comp->steps[i].value2 = comp->steps[j].value2;
    	    comp->steps[i].op = comp->steps[j].op;
    	}
    	comp->nbStep--;
        }
        if (comp->nbStep >= comp->maxStep) {
            xmlStepOpPtr temp;
    	temp = (xmlStepOpPtr) xmlRealloc(comp->steps, comp->maxStep * 2 *
    	                                 sizeof(xmlStepOp));
            if (temp == NULL) {
    	    ERROR(ctxt, NULL, NULL,
    			     "xmlReversePattern: realloc failed\n");
    	    return (-1);
    	}
    	comp->steps = temp;
    	comp->maxStep *= 2;
        }
        i = 0;
        j = comp->nbStep - 1;
        while (j > i) {
    	register const xmlChar *tmp;
    	register xmlPatOp op;
    	tmp = comp->steps[i].value;
    	comp->steps[i].value = comp->steps[j].value;
    	comp->steps[j].value = tmp;
    	tmp = comp->steps[i].value2;
    	comp->steps[i].value2 = comp->steps[j].value2;
    	comp->steps[j].value2 = tmp;
    	op = comp->steps[i].op;
    	comp->steps[i].op = comp->steps[j].op;
    	comp->steps[j].op = op;
    	j--;
    	i++;
        }
        comp->steps[comp->nbStep].value = NULL;
        comp->steps[comp->nbStep].value2 = NULL;
        comp->steps[comp->nbStep++].op = XML_OP_END;
        return(0);
    }
    
    /************************************************************************
     *									*
     *		The interpreter for the precompiled patterns		*
     *									*
     ************************************************************************/
    
    static int
    xmlPatPushState(xmlStepStates *states, int step, xmlNodePtr node) {
        if ((states->states == NULL) || (states->maxstates <= 0)) {
            states->maxstates = 4;
    	states->nbstates = 0;
    	states->states = xmlMalloc(4 * sizeof(xmlStepState));
        }
        else if (states->maxstates <= states->nbstates) {
            xmlStepState *tmp;
    
    	tmp = (xmlStepStatePtr) xmlRealloc(states->states,
    			       2 * states->maxstates * sizeof(xmlStepState));
    	if (tmp == NULL)
    	    return(-1);
    	states->states = tmp;
    	states->maxstates *= 2;
        }
        states->states[states->nbstates].step = step;
        states->states[states->nbstates++].node = node;
    #if 0
        fprintf(stderr, "Push: %d, %s\n", step, node->name);
    #endif
        return(0);
    }
    
    /**
     * xmlPatMatch:
     * @comp: the precompiled pattern
     * @node: a node
     *
     * Test whether the node matches the pattern
     *
     * Returns 1 if it matches, 0 if it doesn't and -1 in case of failure
     */
    static int
    xmlPatMatch(xmlPatternPtr comp, xmlNodePtr node) {
        int i;
        xmlStepOpPtr step;
        xmlStepStates states = {0, 0, NULL}; /* // may require backtrack */
    
        if ((comp == NULL) || (node == NULL)) return(-1);
        i = 0;
    restart:
        for (;i < comp->nbStep;i++) {
    	step = &comp->steps[i];
    	switch (step->op) {
                case XML_OP_END:
    		goto found;
                case XML_OP_ROOT:
    		if (node->type == XML_NAMESPACE_DECL)
    		    goto rollback;
    		node = node->parent;
    		if ((node->type == XML_DOCUMENT_NODE) ||
    #ifdef LIBXML_DOCB_ENABLED
    		    (node->type == XML_DOCB_DOCUMENT_NODE) ||
    #endif
    		    (node->type == XML_HTML_DOCUMENT_NODE))
    		    continue;
    		goto rollback;
                case XML_OP_ELEM:
    		if (node->type != XML_ELEMENT_NODE)
    		    goto rollback;
    		if (step->value == NULL)
    		    continue;
    		if (step->value[0] != node->name[0])
    		    goto rollback;
    		if (!xmlStrEqual(step->value, node->name))
    		    goto rollback;
    
    		/* Namespace test */
    		if (node->ns == NULL) {
    		    if (step->value2 != NULL)
    			goto rollback;
    		} else if (node->ns->href != NULL) {
    		    if (step->value2 == NULL)
    			goto rollback;
    		    if (!xmlStrEqual(step->value2, node->ns->href))
    			goto rollback;
    		}
    		continue;
                case XML_OP_CHILD: {
    		xmlNodePtr lst;
    
    		if ((node->type != XML_ELEMENT_NODE) &&
    		    (node->type != XML_DOCUMENT_NODE) &&
    #ifdef LIBXML_DOCB_ENABLED
    		    (node->type != XML_DOCB_DOCUMENT_NODE) &&
    #endif
    		    (node->type != XML_HTML_DOCUMENT_NODE))
    		    goto rollback;
    
    		lst = node->children;
    
    		if (step->value != NULL) {
    		    while (lst != NULL) {
    			if ((lst->type == XML_ELEMENT_NODE) &&
    			    (step->value[0] == lst->name[0]) &&
    			    (xmlStrEqual(step->value, lst->name)))
    			    break;
    			lst = lst->next;
    		    }
    		    if (lst != NULL)
    			continue;
    		}
    		goto rollback;
    	    }
                case XML_OP_ATTR:
    		if (node->type != XML_ATTRIBUTE_NODE)
    		    goto rollback;
    		if (step->value != NULL) {
    		    if (step->value[0] != node->name[0])
    			goto rollback;
    		    if (!xmlStrEqual(step->value, node->name))
    			goto rollback;
    		}
    		/* Namespace test */
    		if (node->ns == NULL) {
    		    if (step->value2 != NULL)
    			goto rollback;
    		} else if (step->value2 != NULL) {
    		    if (!xmlStrEqual(step->value2, node->ns->href))
    			goto rollback;
    		}
    		continue;
                case XML_OP_PARENT:
    		if ((node->type == XML_DOCUMENT_NODE) ||
    		    (node->type == XML_HTML_DOCUMENT_NODE) ||
    #ifdef LIBXML_DOCB_ENABLED
    		    (node->type == XML_DOCB_DOCUMENT_NODE) ||
    #endif
    		    (node->type == XML_NAMESPACE_DECL))
    		    goto rollback;
    		node = node->parent;
    		if (node == NULL)
    		    goto rollback;
    		if (step->value == NULL)
    		    continue;
    		if (step->value[0] != node->name[0])
    		    goto rollback;
    		if (!xmlStrEqual(step->value, node->name))
    		    goto rollback;
    		/* Namespace test */
    		if (node->ns == NULL) {
    		    if (step->value2 != NULL)
    			goto rollback;
    		} else if (node->ns->href != NULL) {
    		    if (step->value2 == NULL)
    			goto rollback;
    		    if (!xmlStrEqual(step->value2, node->ns->href))
    			goto rollback;
    		}
    		continue;
                case XML_OP_ANCESTOR:
    		/* TODO: implement coalescing of ANCESTOR/NODE ops */
    		if (step->value == NULL) {
    		    i++;
    		    step = &comp->steps[i];
    		    if (step->op == XML_OP_ROOT)
    			goto found;
    		    if (step->op != XML_OP_ELEM)
    			goto rollback;
    		    if (step->value == NULL)
    			return(-1);
    		}
    		if (node == NULL)
    		    goto rollback;
    		if ((node->type == XML_DOCUMENT_NODE) ||
    		    (node->type == XML_HTML_DOCUMENT_NODE) ||
    #ifdef LIBXML_DOCB_ENABLED
    		    (node->type == XML_DOCB_DOCUMENT_NODE) ||
    #endif
    		    (node->type == XML_NAMESPACE_DECL))
    		    goto rollback;
    		node = node->parent;
    		while (node != NULL) {
    		    if ((node->type == XML_ELEMENT_NODE) &&
    			(step->value[0] == node->name[0]) &&
    			(xmlStrEqual(step->value, node->name))) {
    			/* Namespace test */
    			if (node->ns == NULL) {
    			    if (step->value2 == NULL)
    				break;
    			} else if (node->ns->href != NULL) {
    			    if ((step->value2 != NULL) &&
    			        (xmlStrEqual(step->value2, node->ns->href)))
    				break;
    			}
    		    }
    		    node = node->parent;
    		}
    		if (node == NULL)
    		    goto rollback;
    		/*
    		 * prepare a potential rollback from here
    		 * for ancestors of that node.
    		 */
    		if (step->op == XML_OP_ANCESTOR)
    		    xmlPatPushState(&states, i, node);
    		else
    		    xmlPatPushState(&states, i - 1, node);
    		continue;
                case XML_OP_NS:
    		if (node->type != XML_ELEMENT_NODE)
    		    goto rollback;
    		if (node->ns == NULL) {
    		    if (step->value != NULL)
    			goto rollback;
    		} else if (node->ns->href != NULL) {
    		    if (step->value == NULL)
    			goto rollback;
    		    if (!xmlStrEqual(step->value, node->ns->href))
    			goto rollback;
    		}
    		break;
                case XML_OP_ALL:
    		if (node->type != XML_ELEMENT_NODE)
    		    goto rollback;
    		break;
    	}
        }
    found:
        if (states.states != NULL) {
            /* Free the rollback states */
    	xmlFree(states.states);
        }
        return(1);
    rollback:
        /* got an error try to rollback */
        if (states.states == NULL)
    	return(0);
        if (states.nbstates <= 0) {
    	xmlFree(states.states);
    	return(0);
        }
        states.nbstates--;
        i = states.states[states.nbstates].step;
        node = states.states[states.nbstates].node;
    #if 0
        fprintf(stderr, "Pop: %d, %s\n", i, node->name);
    #endif
        goto restart;
    }
    
    /************************************************************************
     *									*
     *			Dedicated parser for templates			*
     *									*
     ************************************************************************/
    
    #define TODO								\
        xmlGenericError(xmlGenericErrorContext,				\
    	    "Unimplemented block at %s:%d\n",				\
                __FILE__, __LINE__);
    #define CUR (*ctxt->cur)
    #define SKIP(val) ctxt->cur += (val)
    #define NXT(val) ctxt->cur[(val)]
    #define PEEKPREV(val) ctxt->cur[-(val)]
    #define CUR_PTR ctxt->cur
    
    #define SKIP_BLANKS							\
        while (IS_BLANK_CH(CUR)) NEXT
    
    #define CURRENT (*ctxt->cur)
    #define NEXT ((*ctxt->cur) ?  ctxt->cur++: ctxt->cur)
    
    
    #define PUSH(op, val, val2)						\
        if (xmlPatternAdd(ctxt, ctxt->comp, (op), (val), (val2))) goto error;
    
    #define XSLT_ERROR(X)							\
        { xsltError(ctxt, __FILE__, __LINE__, X);				\
          ctxt->error = (X); return; }
    
    #define XSLT_ERROR0(X)							\
        { xsltError(ctxt, __FILE__, __LINE__, X);				\
          ctxt->error = (X); return(0); }
    
    #if 0
    /**
     * xmlPatScanLiteral:
     * @ctxt:  the XPath Parser context
     *
     * Parse an XPath Literal:
     *
     * [29] Literal ::= '"' [^"]* '"'
     *                | "'" [^']* "'"
     *
     * Returns the Literal parsed or NULL
     */
    
    static xmlChar *
    xmlPatScanLiteral(xmlPatParserContextPtr ctxt) {
        const xmlChar *q, *cur;
        xmlChar *ret = NULL;
        int val, len;
    
        SKIP_BLANKS;
        if (CUR == '"') {
            NEXT;
    	cur = q = CUR_PTR;
    	val = xmlStringCurrentChar(NULL, cur, &len);
    	while ((IS_CHAR(val)) && (val != '"')) {
    	    cur += len;
    	    val = xmlStringCurrentChar(NULL, cur, &len);
    	}
    	if (!IS_CHAR(val)) {
    	    ctxt->error = 1;
    	    return(NULL);
    	} else {
    	    if (ctxt->dict)
    		ret = (xmlChar *) xmlDictLookup(ctxt->dict, q, cur - q);
    	    else
    		ret = xmlStrndup(q, cur - q);
            }
    	cur += len;
    	CUR_PTR = cur;
        } else if (CUR == '\'') {
            NEXT;
    	cur = q = CUR_PTR;
    	val = xmlStringCurrentChar(NULL, cur, &len);
    	while ((IS_CHAR(val)) && (val != '\'')) {
    	    cur += len;
    	    val = xmlStringCurrentChar(NULL, cur, &len);
    	}
    	if (!IS_CHAR(val)) {
    	    ctxt->error = 1;
    	    return(NULL);
    	} else {
    	    if (ctxt->dict)
    		ret = (xmlChar *) xmlDictLookup(ctxt->dict, q, cur - q);
    	    else
    		ret = xmlStrndup(q, cur - q);
            }
    	cur += len;
    	CUR_PTR = cur;
        } else {
    	/* XP_ERROR(XPATH_START_LITERAL_ERROR); */
    	ctxt->error = 1;
    	return(NULL);
        }
        return(ret);
    }
    #endif
    
    /**
     * xmlPatScanName:
     * @ctxt:  the XPath Parser context
     *
     * [4] NameChar ::= Letter | Digit | '.' | '-' | '_' |
     *                  CombiningChar | Extender
     *
     * [5] Name ::= (Letter | '_' | ':') (NameChar)*
     *
     * [6] Names ::= Name (S Name)*
     *
     * Returns the Name parsed or NULL
     */
    
    static xmlChar *
    xmlPatScanName(xmlPatParserContextPtr ctxt) {
        const xmlChar *q, *cur;
        xmlChar *ret = NULL;
        int val, len;
    
        SKIP_BLANKS;
    
        cur = q = CUR_PTR;
        val = xmlStringCurrentChar(NULL, cur, &len);
        if (!IS_LETTER(val) && (val != '_') && (val != ':'))
    	return(NULL);
    
        while ((IS_LETTER(val)) || (IS_DIGIT(val)) ||
               (val == '.') || (val == '-') ||
    	   (val == '_') ||
    	   (IS_COMBINING(val)) ||
    	   (IS_EXTENDER(val))) {
    	cur += len;
    	val = xmlStringCurrentChar(NULL, cur, &len);
        }
        if (ctxt->dict)
    	ret = (xmlChar *) xmlDictLookup(ctxt->dict, q, cur - q);
        else
    	ret = xmlStrndup(q, cur - q);
        CUR_PTR = cur;
        return(ret);
    }
    
    /**
     * xmlPatScanNCName:
     * @ctxt:  the XPath Parser context
     *
     * Parses a non qualified name
     *
     * Returns the Name parsed or NULL
     */
    
    static xmlChar *
    xmlPatScanNCName(xmlPatParserContextPtr ctxt) {
        const xmlChar *q, *cur;
        xmlChar *ret = NULL;
        int val, len;
    
        SKIP_BLANKS;
    
        cur = q = CUR_PTR;
        val = xmlStringCurrentChar(NULL, cur, &len);
        if (!IS_LETTER(val) && (val != '_'))
    	return(NULL);
    
        while ((IS_LETTER(val)) || (IS_DIGIT(val)) ||
               (val == '.') || (val == '-') ||
    	   (val == '_') ||
    	   (IS_COMBINING(val)) ||
    	   (IS_EXTENDER(val))) {
    	cur += len;
    	val = xmlStringCurrentChar(NULL, cur, &len);
        }
        if (ctxt->dict)
    	ret = (xmlChar *) xmlDictLookup(ctxt->dict, q, cur - q);
        else
    	ret = xmlStrndup(q, cur - q);
        CUR_PTR = cur;
        return(ret);
    }
    
    #if 0
    /**
     * xmlPatScanQName:
     * @ctxt:  the XPath Parser context
     * @prefix:  the place to store the prefix
     *
     * Parse a qualified name
     *
     * Returns the Name parsed or NULL
     */
    
    static xmlChar *
    xmlPatScanQName(xmlPatParserContextPtr ctxt, xmlChar **prefix) {
        xmlChar *ret = NULL;
    
        *prefix = NULL;
        ret = xmlPatScanNCName(ctxt);
        if (CUR == ':') {
            *prefix = ret;
    	NEXT;
    	ret = xmlPatScanNCName(ctxt);
        }
        return(ret);
    }
    #endif
    
    /**
     * xmlCompileAttributeTest:
     * @ctxt:  the compilation context
     *
     * Compile an attribute test.
     */
    static void
    xmlCompileAttributeTest(xmlPatParserContextPtr ctxt) {
        xmlChar *token = NULL;
        xmlChar *name = NULL;
        xmlChar *URL = NULL;
    
        SKIP_BLANKS;
        name = xmlPatScanNCName(ctxt);
        if (name == NULL) {
    	if (CUR == '*') {
    	    PUSH(XML_OP_ATTR, NULL, NULL);
    	    NEXT;
    	} else {
    	    ERROR(NULL, NULL, NULL,
    		"xmlCompileAttributeTest : Name expected\n");
    	    ctxt->error = 1;
    	}
    	return;
        }
        if (CUR == ':') {
    	int i;
    	xmlChar *prefix = name;
    
    	NEXT;
    
    	if (IS_BLANK_CH(CUR)) {
    	    ERROR5(NULL, NULL, NULL, "Invalid QName.\n", NULL);
    	    XML_PAT_FREE_STRING(ctxt, prefix);
    	    ctxt->error = 1;
    	    goto error;
    	}
    	/*
    	* This is a namespace match
    	*/
    	token = xmlPatScanName(ctxt);
    	if ((prefix[0] == 'x') &&
    	    (prefix[1] == 'm') &&
    	    (prefix[2] == 'l') &&
    	    (prefix[3] == 0))
    	{
    	    XML_PAT_COPY_NSNAME(ctxt, URL, XML_XML_NAMESPACE);
    	} else {
    	    for (i = 0;i < ctxt->nb_namespaces;i++) {
    		if (xmlStrEqual(ctxt->namespaces[2 * i + 1], prefix)) {
    		    XML_PAT_COPY_NSNAME(ctxt, URL, ctxt->namespaces[2 * i])
    		    break;
    		}
    	    }
    	    if (i >= ctxt->nb_namespaces) {
    		ERROR5(NULL, NULL, NULL,
    		    "xmlCompileAttributeTest : no namespace bound to prefix %s\n",
    		    prefix);
    	        XML_PAT_FREE_STRING(ctxt, prefix);
    		ctxt->error = 1;
    		goto error;
    	    }
    	}
    	XML_PAT_FREE_STRING(ctxt, prefix);
    	if (token == NULL) {
    	    if (CUR == '*') {
    		NEXT;
    		PUSH(XML_OP_ATTR, NULL, URL);
    	    } else {
    		ERROR(NULL, NULL, NULL,
    		    "xmlCompileAttributeTest : Name expected\n");
    		ctxt->error = 1;
    		goto error;
    	    }
    	} else {
    	    PUSH(XML_OP_ATTR, token, URL);
    	}
        } else {
    	PUSH(XML_OP_ATTR, name, NULL);
        }
        return;
    error:
        if (URL != NULL)
    	XML_PAT_FREE_STRING(ctxt, URL)
        if (token != NULL)
    	XML_PAT_FREE_STRING(ctxt, token);
    }
    
    /**
     * xmlCompileStepPattern:
     * @ctxt:  the compilation context
     *
     * Compile the Step Pattern and generates a precompiled
     * form suitable for fast matching.
     *
     * [3]    Step    ::=    '.' | NameTest
     * [4]    NameTest    ::=    QName | '*' | NCName ':' '*'
     */
    
    static void
    xmlCompileStepPattern(xmlPatParserContextPtr ctxt) {
        xmlChar *token = NULL;
        xmlChar *name = NULL;
        xmlChar *URL = NULL;
        int hasBlanks = 0;
    
        SKIP_BLANKS;
        if (CUR == '.') {
    	/*
    	* Context node.
    	*/
    	NEXT;
    	PUSH(XML_OP_ELEM, NULL, NULL);
    	return;
        }
        if (CUR == '@') {
    	/*
    	* Attribute test.
    	*/
    	if (XML_STREAM_XS_IDC_SEL(ctxt->comp)) {
    	    ERROR5(NULL, NULL, NULL,
    		"Unexpected attribute axis in '%s'.\n", ctxt->base);
    	    ctxt->error = 1;
    	    return;
    	}
    	NEXT;
    	xmlCompileAttributeTest(ctxt);
    	if (ctxt->error != 0)
    	    goto error;
    	return;
        }
        name = xmlPatScanNCName(ctxt);
        if (name == NULL) {
    	if (CUR == '*') {
    	    NEXT;
    	    PUSH(XML_OP_ALL, NULL, NULL);
    	    return;
    	} else {
    	    ERROR(NULL, NULL, NULL,
    		    "xmlCompileStepPattern : Name expected\n");
    	    ctxt->error = 1;
    	    return;
    	}
        }
        if (IS_BLANK_CH(CUR)) {
    	hasBlanks = 1;
    	SKIP_BLANKS;
        }
        if (CUR == ':') {
    	NEXT;
    	if (CUR != ':') {
    	    xmlChar *prefix = name;
    	    int i;
    
    	    if (hasBlanks || IS_BLANK_CH(CUR)) {
    		ERROR5(NULL, NULL, NULL, "Invalid QName.\n", NULL);
    		ctxt->error = 1;
    		goto error;
    	    }
    	    /*
    	     * This is a namespace match
    	     */
    	    token = xmlPatScanName(ctxt);
    	    if ((prefix[0] == 'x') &&
    		(prefix[1] == 'm') &&
    		(prefix[2] == 'l') &&
    		(prefix[3] == 0))
    	    {
    		XML_PAT_COPY_NSNAME(ctxt, URL, XML_XML_NAMESPACE)
    	    } else {
    		for (i = 0;i < ctxt->nb_namespaces;i++) {
    		    if (xmlStrEqual(ctxt->namespaces[2 * i + 1], prefix)) {
    			XML_PAT_COPY_NSNAME(ctxt, URL, ctxt->namespaces[2 * i])
    			break;
    		    }
    		}
    		if (i >= ctxt->nb_namespaces) {
    		    ERROR5(NULL, NULL, NULL,
    			"xmlCompileStepPattern : no namespace bound to prefix %s\n",
    			prefix);
    		    ctxt->error = 1;
    		    goto error;
    		}
    	    }
    	    XML_PAT_FREE_STRING(ctxt, prefix);
    	    name = NULL;
    	    if (token == NULL) {
    		if (CUR == '*') {
    		    NEXT;
    		    PUSH(XML_OP_NS, URL, NULL);
    		} else {
    		    ERROR(NULL, NULL, NULL,
    			    "xmlCompileStepPattern : Name expected\n");
    		    ctxt->error = 1;
    		    goto error;
    		}
    	    } else {
    		PUSH(XML_OP_ELEM, token, URL);
    	    }
    	} else {
    	    NEXT;
    	    if (xmlStrEqual(name, (const xmlChar *) "child")) {
    		XML_PAT_FREE_STRING(ctxt, name);
    		name = xmlPatScanName(ctxt);
    		if (name == NULL) {
    		    if (CUR == '*') {
    			NEXT;
    			PUSH(XML_OP_ALL, NULL, NULL);
    			return;
    		    } else {
    			ERROR(NULL, NULL, NULL,
    			    "xmlCompileStepPattern : QName expected\n");
    			ctxt->error = 1;
    			goto error;
    		    }
    		}
    		if (CUR == ':') {
    		    xmlChar *prefix = name;
    		    int i;
    
    		    NEXT;
    		    if (IS_BLANK_CH(CUR)) {
    			ERROR5(NULL, NULL, NULL, "Invalid QName.\n", NULL);
    			ctxt->error = 1;
    			goto error;
    		    }
    		    /*
    		    * This is a namespace match
    		    */
    		    token = xmlPatScanName(ctxt);
    		    if ((prefix[0] == 'x') &&
    			(prefix[1] == 'm') &&
    			(prefix[2] == 'l') &&
    			(prefix[3] == 0))
    		    {
    			XML_PAT_COPY_NSNAME(ctxt, URL, XML_XML_NAMESPACE)
    		    } else {
    			for (i = 0;i < ctxt->nb_namespaces;i++) {
    			    if (xmlStrEqual(ctxt->namespaces[2 * i + 1], prefix)) {
    				XML_PAT_COPY_NSNAME(ctxt, URL, ctxt->namespaces[2 * i])
    				break;
    			    }
    			}
    			if (i >= ctxt->nb_namespaces) {
    			    ERROR5(NULL, NULL, NULL,
    				"xmlCompileStepPattern : no namespace bound "
    				"to prefix %s\n", prefix);
    			    ctxt->error = 1;
    			    goto error;
    			}
    		    }
    		    XML_PAT_FREE_STRING(ctxt, prefix);
    		    name = NULL;
    		    if (token == NULL) {
    			if (CUR == '*') {
    			    NEXT;
    			    PUSH(XML_OP_NS, URL, NULL);
    			} else {
    			    ERROR(NULL, NULL, NULL,
    				"xmlCompileStepPattern : Name expected\n");
    			    ctxt->error = 1;
    			    goto error;
    			}
    		    } else {
    			PUSH(XML_OP_CHILD, token, URL);
    		    }
    		} else
    		    PUSH(XML_OP_CHILD, name, NULL);
    		return;
    	    } else if (xmlStrEqual(name, (const xmlChar *) "attribute")) {
    		XML_PAT_FREE_STRING(ctxt, name)
    		name = NULL;
    		if (XML_STREAM_XS_IDC_SEL(ctxt->comp)) {
    		    ERROR5(NULL, NULL, NULL,
    			"Unexpected attribute axis in '%s'.\n", ctxt->base);
    		    ctxt->error = 1;
    		    goto error;
    		}
    		xmlCompileAttributeTest(ctxt);
    		if (ctxt->error != 0)
    		    goto error;
    		return;
    	    } else {
    		ERROR5(NULL, NULL, NULL,
    		    "The 'element' or 'attribute' axis is expected.\n", NULL);
    		ctxt->error = 1;
    		goto error;
    	    }
    	}
        } else if (CUR == '*') {
            if (name != NULL) {
    	    ctxt->error = 1;
    	    goto error;
    	}
    	NEXT;
    	PUSH(XML_OP_ALL, token, NULL);
        } else {
    	PUSH(XML_OP_ELEM, name, NULL);
        }
        return;
    error:
        if (URL != NULL)
    	XML_PAT_FREE_STRING(ctxt, URL)
        if (token != NULL)
    	XML_PAT_FREE_STRING(ctxt, token)
        if (name != NULL)
    	XML_PAT_FREE_STRING(ctxt, name)
    }
    
    /**
     * xmlCompilePathPattern:
     * @ctxt:  the compilation context
     *
     * Compile the Path Pattern and generates a precompiled
     * form suitable for fast matching.
     *
     * [5]    Path    ::=    ('.//')? ( Step '/' )* ( Step | '@' NameTest )
     */
    static void
    xmlCompilePathPattern(xmlPatParserContextPtr ctxt) {
        SKIP_BLANKS;
        if (CUR == '/') {
            ctxt->comp->flags |= PAT_FROM_ROOT;
        } else if ((CUR == '.') || (ctxt->comp->flags & XML_PATTERN_NOTPATTERN)) {
            ctxt->comp->flags |= PAT_FROM_CUR;
        }
    
        if ((CUR == '/') && (NXT(1) == '/')) {
    	PUSH(XML_OP_ANCESTOR, NULL, NULL);
    	NEXT;
    	NEXT;
        } else if ((CUR == '.') && (NXT(1) == '/') && (NXT(2) == '/')) {
    	PUSH(XML_OP_ANCESTOR, NULL, NULL);
    	NEXT;
    	NEXT;
    	NEXT;
    	/* Check for incompleteness. */
    	SKIP_BLANKS;
    	if (CUR == 0) {
    	    ERROR5(NULL, NULL, NULL,
    	       "Incomplete expression '%s'.\n", ctxt->base);
    	    ctxt->error = 1;
    	    goto error;
    	}
        }
        if (CUR == '@') {
    	NEXT;
    	xmlCompileAttributeTest(ctxt);
    	SKIP_BLANKS;
    	/* TODO: check for incompleteness */
    	if (CUR != 0) {
    	    xmlCompileStepPattern(ctxt);
    	    if (ctxt->error != 0)
    		goto error;
    	}
        } else {
            if (CUR == '/') {
    	    PUSH(XML_OP_ROOT, NULL, NULL);
    	    NEXT;
    	    /* Check for incompleteness. */
    	    SKIP_BLANKS;
    	    if (CUR == 0) {
    		ERROR5(NULL, NULL, NULL,
    		    "Incomplete expression '%s'.\n", ctxt->base);
    		ctxt->error = 1;
    		goto error;
    	    }
    	}
    	xmlCompileStepPattern(ctxt);
    	if (ctxt->error != 0)
    	    goto error;
    	SKIP_BLANKS;
    	while (CUR == '/') {
    	    if (NXT(1) == '/') {
    	        PUSH(XML_OP_ANCESTOR, NULL, NULL);
    		NEXT;
    		NEXT;
    		SKIP_BLANKS;
    		xmlCompileStepPattern(ctxt);
    		if (ctxt->error != 0)
    		    goto error;
    	    } else {
    	        PUSH(XML_OP_PARENT, NULL, NULL);
    		NEXT;
    		SKIP_BLANKS;
    		if (CUR == 0) {
    		    ERROR5(NULL, NULL, NULL,
    		    "Incomplete expression '%s'.\n", ctxt->base);
    		    ctxt->error = 1;
    		    goto error;
    		}
    		xmlCompileStepPattern(ctxt);
    		if (ctxt->error != 0)
    		    goto error;
    	    }
    	}
        }
        if (CUR != 0) {
    	ERROR5(NULL, NULL, NULL,
    	       "Failed to compile pattern %s\n", ctxt->base);
    	ctxt->error = 1;
        }
    error:
        return;
    }
    
    /**
     * xmlCompileIDCXPathPath:
     * @ctxt:  the compilation context
     *
     * Compile the Path Pattern and generates a precompiled
     * form suitable for fast matching.
     *
     * [5]    Path    ::=    ('.//')? ( Step '/' )* ( Step | '@' NameTest )
     */
    static void
    xmlCompileIDCXPathPath(xmlPatParserContextPtr ctxt) {
        SKIP_BLANKS;
        if (CUR == '/') {
    	ERROR5(NULL, NULL, NULL,
    	    "Unexpected selection of the document root in '%s'.\n",
    	    ctxt->base);
    	goto error;
        }
        ctxt->comp->flags |= PAT_FROM_CUR;
    
        if (CUR == '.') {
    	/* "." - "self::node()" */
    	NEXT;
    	SKIP_BLANKS;
    	if (CUR == 0) {
    	    /*
    	    * Selection of the context node.
    	    */
    	    PUSH(XML_OP_ELEM, NULL, NULL);
    	    return;
    	}
    	if (CUR != '/') {
    	    /* TODO: A more meaningful error message. */
    	    ERROR5(NULL, NULL, NULL,
    	    "Unexpected token after '.' in '%s'.\n", ctxt->base);
    	    goto error;
    	}
    	/* "./" - "self::node()/" */
    	NEXT;
    	SKIP_BLANKS;
    	if (CUR == '/') {
    	    if (IS_BLANK_CH(PEEKPREV(1))) {
    		/*
    		* Disallow "./ /"
    		*/
    		ERROR5(NULL, NULL, NULL,
    		    "Unexpected '/' token in '%s'.\n", ctxt->base);
    		goto error;
    	    }
    	    /* ".//" - "self:node()/descendant-or-self::node()/" */
    	    PUSH(XML_OP_ANCESTOR, NULL, NULL);
    	    NEXT;
    	    SKIP_BLANKS;
    	}
    	if (CUR == 0)
    	    goto error_unfinished;
        }
        /*
        * Process steps.
        */
        do {
    	xmlCompileStepPattern(ctxt);
    	if (ctxt->error != 0)
    	    goto error;
    	SKIP_BLANKS;
    	if (CUR != '/')
    	    break;
    	PUSH(XML_OP_PARENT, NULL, NULL);
    	NEXT;
    	SKIP_BLANKS;
    	if (CUR == '/') {
    	    /*
    	    * Disallow subsequent '//'.
    	    */
    	    ERROR5(NULL, NULL, NULL,
    		"Unexpected subsequent '//' in '%s'.\n",
    		ctxt->base);
    	    goto error;
    	}
    	if (CUR == 0)
    	    goto error_unfinished;
    
        } while (CUR != 0);
    
        if (CUR != 0) {
    	ERROR5(NULL, NULL, NULL,
    	    "Failed to compile expression '%s'.\n", ctxt->base);
    	ctxt->error = 1;
        }
        return;
    error:
        ctxt->error = 1;
        return;
    
    error_unfinished:
        ctxt->error = 1;
        ERROR5(NULL, NULL, NULL,
    	"Unfinished expression '%s'.\n", ctxt->base);
        return;
    }
    
    /************************************************************************
     *									*
     *			The streaming code				*
     *									*
     ************************************************************************/
    
    #ifdef DEBUG_STREAMING
    static void
    xmlDebugStreamComp(xmlStreamCompPtr stream) {
        int i;
    
        if (stream == NULL) {
            printf("Stream: NULL\n");
    	return;
        }
        printf("Stream: %d steps\n", stream->nbStep);
        for (i = 0;i < stream->nbStep;i++) {
    	if (stream->steps[i].ns != NULL) {
    	    printf("{%s}", stream->steps[i].ns);
    	}
            if (stream->steps[i].name == NULL) {
    	    printf("* ");
    	} else {
    	    printf("%s ", stream->steps[i].name);
    	}
    	if (stream->steps[i].flags & XML_STREAM_STEP_ROOT)
    	    printf("root ");
    	if (stream->steps[i].flags & XML_STREAM_STEP_DESC)
    	    printf("// ");
    	if (stream->steps[i].flags & XML_STREAM_STEP_FINAL)
    	    printf("final ");
    	printf("\n");
        }
    }
    static void
    xmlDebugStreamCtxt(xmlStreamCtxtPtr ctxt, int match) {
        int i;
    
        if (ctxt == NULL) {
            printf("Stream: NULL\n");
    	return;
        }
        printf("Stream: level %d, %d states: ", ctxt->level, ctxt->nbState);
        if (match)
            printf("matches\n");
        else
            printf("\n");
        for (i = 0;i < ctxt->nbState;i++) {
            if (ctxt->states[2 * i] < 0)
    	    printf(" %d: free\n", i);
    	else {
    	    printf(" %d: step %d, level %d", i, ctxt->states[2 * i],
    	           ctxt->states[(2 * i) + 1]);
                if (ctxt->comp->steps[ctxt->states[2 * i]].flags &
    	        XML_STREAM_STEP_DESC)
    	        printf(" //\n");
    	    else
    	        printf("\n");
    	}
        }
    }
    #endif
    /**
     * xmlNewStreamComp:
     * @size: the number of expected steps
     *
     * build a new compiled pattern for streaming
     *
     * Returns the new structure or NULL in case of error.
     */
    static xmlStreamCompPtr
    xmlNewStreamComp(int size) {
        xmlStreamCompPtr cur;
    
        if (size < 4)
            size  = 4;
    
        cur = (xmlStreamCompPtr) xmlMalloc(sizeof(xmlStreamComp));
        if (cur == NULL) {
    	ERROR(NULL, NULL, NULL,
    		"xmlNewStreamComp: malloc failed\n");
    	return(NULL);
        }
        memset(cur, 0, sizeof(xmlStreamComp));
        cur->steps = (xmlStreamStepPtr) xmlMalloc(size * sizeof(xmlStreamStep));
        if (cur->steps == NULL) {
    	xmlFree(cur);
    	ERROR(NULL, NULL, NULL,
    	      "xmlNewStreamComp: malloc failed\n");
    	return(NULL);
        }
        cur->nbStep = 0;
        cur->maxStep = size;
        return(cur);
    }
    
    /**
     * xmlFreeStreamComp:
     * @comp: the compiled pattern for streaming
     *
     * Free the compiled pattern for streaming
     */
    static void
    xmlFreeStreamComp(xmlStreamCompPtr comp) {
        if (comp != NULL) {
            if (comp->steps != NULL)
    	    xmlFree(comp->steps);
    	if (comp->dict != NULL)
    	    xmlDictFree(comp->dict);
            xmlFree(comp);
        }
    }
    
    /**
     * xmlStreamCompAddStep:
     * @comp: the compiled pattern for streaming
     * @name: the first string, the name, or NULL for *
     * @ns: the second step, the namespace name
     * @flags: the flags for that step
     *
     * Add a new step to the compiled pattern
     *
     * Returns -1 in case of error or the step index if successful
     */
    static int
    xmlStreamCompAddStep(xmlStreamCompPtr comp, const xmlChar *name,
                         const xmlChar *ns, int nodeType, int flags) {
        xmlStreamStepPtr cur;
    
        if (comp->nbStep >= comp->maxStep) {
    	cur = (xmlStreamStepPtr) xmlRealloc(comp->steps,
    				 comp->maxStep * 2 * sizeof(xmlStreamStep));
    	if (cur == NULL) {
    	    ERROR(NULL, NULL, NULL,
    		  "xmlNewStreamComp: malloc failed\n");
    	    return(-1);
    	}
    	comp->steps = cur;
            comp->maxStep *= 2;
        }
        cur = &comp->steps[comp->nbStep++];
        cur->flags = flags;
        cur->name = name;
        cur->ns = ns;
        cur->nodeType = nodeType;
        return(comp->nbStep - 1);
    }
    
    /**
     * xmlStreamCompile:
     * @comp: the precompiled pattern
     *
     * Tries to stream compile a pattern
     *
     * Returns -1 in case of failure and 0 in case of success.
     */
    static int
    xmlStreamCompile(xmlPatternPtr comp) {
        xmlStreamCompPtr stream;
        int i, s = 0, root = 0, flags = 0, prevs = -1;
        xmlStepOp step;
    
        if ((comp == NULL) || (comp->steps == NULL))
            return(-1);
        /*
         * special case for .
         */
        if ((comp->nbStep == 1) &&
            (comp->steps[0].op == XML_OP_ELEM) &&
    	(comp->steps[0].value == NULL) &&
    	(comp->steps[0].value2 == NULL)) {
    	stream = xmlNewStreamComp(0);
    	if (stream == NULL)
    	    return(-1);
    	/* Note that the stream will have no steps in this case. */
    	stream->flags |= XML_STREAM_FINAL_IS_ANY_NODE;
    	comp->stream = stream;
    	return(0);
        }
    
        stream = xmlNewStreamComp((comp->nbStep / 2) + 1);
        if (stream == NULL)
            return(-1);
        if (comp->dict != NULL) {
            stream->dict = comp->dict;
    	xmlDictReference(stream->dict);
        }
    
        i = 0;
        if (comp->flags & PAT_FROM_ROOT)
    	stream->flags |= XML_STREAM_FROM_ROOT;
    
        for (;i < comp->nbStep;i++) {
    	step = comp->steps[i];
            switch (step.op) {
    	    case XML_OP_END:
    	        break;
    	    case XML_OP_ROOT:
    	        if (i != 0)
    		    goto error;
    		root = 1;
    		break;
    	    case XML_OP_NS:
    		s = xmlStreamCompAddStep(stream, NULL, step.value,
    		    XML_ELEMENT_NODE, flags);
    		if (s < 0)
    		    goto error;
    		prevs = s;
    		flags = 0;
    		break;
    	    case XML_OP_ATTR:
    		flags |= XML_STREAM_STEP_ATTR;
    		prevs = -1;
    		s = xmlStreamCompAddStep(stream,
    		    step.value, step.value2, XML_ATTRIBUTE_NODE, flags);
    		flags = 0;
    		if (s < 0)
    		    goto error;
    		break;
    	    case XML_OP_ELEM:
    	        if ((step.value == NULL) && (step.value2 == NULL)) {
    		    /*
    		    * We have a "." or "self::node()" here.
    		    * Eliminate redundant self::node() tests like in "/./."
    		    * or "//./"
    		    * The only case we won't eliminate is "//.", i.e. if
    		    * self::node() is the last node test and we had
    		    * continuation somewhere beforehand.
    		    */
    		    if ((comp->nbStep == i + 1) &&
    			(flags & XML_STREAM_STEP_DESC)) {
    			/*
    			* Mark the special case where the expression resolves
    			* to any type of node.
    			*/
    			if (comp->nbStep == i + 1) {
    			    stream->flags |= XML_STREAM_FINAL_IS_ANY_NODE;
    			}
    			flags |= XML_STREAM_STEP_NODE;
    			s = xmlStreamCompAddStep(stream, NULL, NULL,
    			    XML_STREAM_ANY_NODE, flags);
    			if (s < 0)
    			    goto error;
    			flags = 0;
    			/*
    			* If there was a previous step, mark it to be added to
    			* the result node-set; this is needed since only
    			* the last step will be marked as "final" and only
    			* "final" nodes are added to the resulting set.
    			*/
    			if (prevs != -1) {
    			    stream->steps[prevs].flags |= XML_STREAM_STEP_IN_SET;
    			    prevs = -1;
    			}
    			break;
    
    		    } else {
    			/* Just skip this one. */
    			continue;
    		    }
    		}
    		/* An element node. */
    	        s = xmlStreamCompAddStep(stream, step.value, step.value2,
    		    XML_ELEMENT_NODE, flags);
    		if (s < 0)
    		    goto error;
    		prevs = s;
    		flags = 0;
    		break;
    	    case XML_OP_CHILD:
    		/* An element node child. */
    	        s = xmlStreamCompAddStep(stream, step.value, step.value2,
    		    XML_ELEMENT_NODE, flags);
    		if (s < 0)
    		    goto error;
    		prevs = s;
    		flags = 0;
    		break;
    	    case XML_OP_ALL:
    	        s = xmlStreamCompAddStep(stream, NULL, NULL,
    		    XML_ELEMENT_NODE, flags);
    		if (s < 0)
    		    goto error;
    		prevs = s;
    		flags = 0;
    		break;
    	    case XML_OP_PARENT:
    	        break;
    	    case XML_OP_ANCESTOR:
    		/* Skip redundant continuations. */
    		if (flags & XML_STREAM_STEP_DESC)
    		    break;
    	        flags |= XML_STREAM_STEP_DESC;
    		/*
    		* Mark the expression as having "//".
    		*/
    		if ((stream->flags & XML_STREAM_DESC) == 0)
    		    stream->flags |= XML_STREAM_DESC;
    		break;
    	}
        }
        if ((! root) && (comp->flags & XML_PATTERN_NOTPATTERN) == 0) {
    	/*
    	* If this should behave like a real pattern, we will mark
    	* the first step as having "//", to be reentrant on every
    	* tree level.
    	*/
    	if ((stream->flags & XML_STREAM_DESC) == 0)
    	    stream->flags |= XML_STREAM_DESC;
    
    	if (stream->nbStep > 0) {
    	    if ((stream->steps[0].flags & XML_STREAM_STEP_DESC) == 0)
    		stream->steps[0].flags |= XML_STREAM_STEP_DESC;
    	}
        }
        if (stream->nbStep <= s)
    	goto error;
        stream->steps[s].flags |= XML_STREAM_STEP_FINAL;
        if (root)
    	stream->steps[0].flags |= XML_STREAM_STEP_ROOT;
    #ifdef DEBUG_STREAMING
        xmlDebugStreamComp(stream);
    #endif
        comp->stream = stream;
        return(0);
    error:
        xmlFreeStreamComp(stream);
        return(0);
    }
    
    /**
     * xmlNewStreamCtxt:
     * @size: the number of expected states
     *
     * build a new stream context
     *
     * Returns the new structure or NULL in case of error.
     */
    static xmlStreamCtxtPtr
    xmlNewStreamCtxt(xmlStreamCompPtr stream) {
        xmlStreamCtxtPtr cur;
    
        cur = (xmlStreamCtxtPtr) xmlMalloc(sizeof(xmlStreamCtxt));
        if (cur == NULL) {
    	ERROR(NULL, NULL, NULL,
    		"xmlNewStreamCtxt: malloc failed\n");
    	return(NULL);
        }
        memset(cur, 0, sizeof(xmlStreamCtxt));
        cur->states = (int *) xmlMalloc(4 * 2 * sizeof(int));
        if (cur->states == NULL) {
    	xmlFree(cur);
    	ERROR(NULL, NULL, NULL,
    	      "xmlNewStreamCtxt: malloc failed\n");
    	return(NULL);
        }
        cur->nbState = 0;
        cur->maxState = 4;
        cur->level = 0;
        cur->comp = stream;
        cur->blockLevel = -1;
        return(cur);
    }
    
    /**
     * xmlFreeStreamCtxt:
     * @stream: the stream context
     *
     * Free the stream context
     */
    void
    xmlFreeStreamCtxt(xmlStreamCtxtPtr stream) {
        xmlStreamCtxtPtr next;
    
        while (stream != NULL) {
            next = stream->next;
            if (stream->states != NULL)
    	    xmlFree(stream->states);
            xmlFree(stream);
    	stream = next;
        }
    }
    
    /**
     * xmlStreamCtxtAddState:
     * @comp: the stream context
     * @idx: the step index for that streaming state
     *
     * Add a new state to the stream context
     *
     * Returns -1 in case of error or the state index if successful
     */
    static int
    xmlStreamCtxtAddState(xmlStreamCtxtPtr comp, int idx, int level) {
        int i;
        for (i = 0;i < comp->nbState;i++) {
            if (comp->states[2 * i] < 0) {
    	    comp->states[2 * i] = idx;
    	    comp->states[2 * i + 1] = level;
    	    return(i);
    	}
        }
        if (comp->nbState >= comp->maxState) {
            int *cur;
    
    	cur = (int *) xmlRealloc(comp->states,
    				 comp->maxState * 4 * sizeof(int));
    	if (cur == NULL) {
    	    ERROR(NULL, NULL, NULL,
    		  "xmlNewStreamCtxt: malloc failed\n");
    	    return(-1);
    	}
    	comp->states = cur;
            comp->maxState *= 2;
        }
        comp->states[2 * comp->nbState] = idx;
        comp->states[2 * comp->nbState++ + 1] = level;
        return(comp->nbState - 1);
    }
    
    /**
     * xmlStreamPushInternal:
     * @stream: the stream context
     * @name: the current name
     * @ns: the namespace name
     * @nodeType: the type of the node
     *
     * Push new data onto the stream. NOTE: if the call xmlPatterncompile()
     * indicated a dictionary, then strings for name and ns will be expected
     * to come from the dictionary.
     * Both @name and @ns being NULL means the / i.e. the root of the document.
     * This can also act as a reset.
     *
     * Returns: -1 in case of error, 1 if the current state in the stream is a
     *    match and 0 otherwise.
     */
    static int
    xmlStreamPushInternal(xmlStreamCtxtPtr stream,
    		      const xmlChar *name, const xmlChar *ns,
    		      int nodeType) {
        int ret = 0, err = 0, final = 0, tmp, i, m, match, stepNr, desc;
        xmlStreamCompPtr comp;
        xmlStreamStep step;
    #ifdef DEBUG_STREAMING
        xmlStreamCtxtPtr orig = stream;
    #endif
    
        if ((stream == NULL) || (stream->nbState < 0))
            return(-1);
    
        while (stream != NULL) {
    	comp = stream->comp;
    
    	if ((nodeType == XML_ELEMENT_NODE) &&
    	    (name == NULL) && (ns == NULL)) {
    	    /* We have a document node here (or a reset). */
    	    stream->nbState = 0;
    	    stream->level = 0;
    	    stream->blockLevel = -1;
    	    if (comp->flags & XML_STREAM_FROM_ROOT) {
    		if (comp->nbStep == 0) {
    		    /* TODO: We have a "/." here? */
    		    ret = 1;
    		} else {
    		    if ((comp->nbStep == 1) &&
    			(comp->steps[0].nodeType == XML_STREAM_ANY_NODE) &&
    			(comp->steps[0].flags & XML_STREAM_STEP_DESC))
    		    {
    			/*
    			* In the case of "//." the document node will match
    			* as well.
    			*/
    			ret = 1;
    		    } else if (comp->steps[0].flags & XML_STREAM_STEP_ROOT) {
    			/* TODO: Do we need this ? */
    			tmp = xmlStreamCtxtAddState(stream, 0, 0);
    			if (tmp < 0)
    			    err++;
    		    }
    		}
    	    }
    	    stream = stream->next;
    	    continue; /* while */
    	}
    
    	/*
    	* Fast check for ".".
    	*/
    	if (comp->nbStep == 0) {
    	    /*
    	     * / and . are handled at the XPath node set creation
    	     * level by checking min depth
    	     */
    	    if (stream->flags & XML_PATTERN_XPATH) {
    		stream = stream->next;
    		continue; /* while */
    	    }
    	    /*
    	    * For non-pattern like evaluation like XML Schema IDCs
    	    * or traditional XPath expressions, this will match if
    	    * we are at the first level only, otherwise on every level.
    	    */
    	    if ((nodeType != XML_ATTRIBUTE_NODE) &&
    		(((stream->flags & XML_PATTERN_NOTPATTERN) == 0) ||
    		(stream->level == 0))) {
    		    ret = 1;
    	    }
    	    stream->level++;
    	    goto stream_next;
    	}
    	if (stream->blockLevel != -1) {
    	    /*
    	    * Skip blocked expressions.
    	    */
    	    stream->level++;
    	    goto stream_next;
    	}
    
    	if ((nodeType != XML_ELEMENT_NODE) &&
    	    (nodeType != XML_ATTRIBUTE_NODE) &&
    	    ((comp->flags & XML_STREAM_FINAL_IS_ANY_NODE) == 0)) {
    	    /*
    	    * No need to process nodes of other types if we don't
    	    * resolve to those types.
    	    * TODO: Do we need to block the context here?
    	    */
    	    stream->level++;
    	    goto stream_next;
    	}
    
    	/*
    	 * Check evolution of existing states
    	 */
    	i = 0;
    	m = stream->nbState;
    	while (i < m) {
    	    if ((comp->flags & XML_STREAM_DESC) == 0) {
    		/*
    		* If there is no "//", then only the last
    		* added state is of interest.
    		*/
    		stepNr = stream->states[2 * (stream->nbState -1)];
    		/*
    		* TODO: Security check, should not happen, remove it.
    		*/
    		if (stream->states[(2 * (stream->nbState -1)) + 1] <
    		    stream->level) {
    		    return (-1);
    		}
    		desc = 0;
    		/* loop-stopper */
    		i = m;
    	    } else {
    		/*
    		* If there are "//", then we need to process every "//"
    		* occurring in the states, plus any other state for this
    		* level.
    		*/
    		stepNr = stream->states[2 * i];
    
    		/* TODO: should not happen anymore: dead states */
    		if (stepNr < 0)
    		    goto next_state;
    
    		tmp = stream->states[(2 * i) + 1];
    
    		/* skip new states just added */
    		if (tmp > stream->level)
    		    goto next_state;
    
    		/* skip states at ancestor levels, except if "//" */
    		desc = comp->steps[stepNr].flags & XML_STREAM_STEP_DESC;
    		if ((tmp < stream->level) && (!desc))
    		    goto next_state;
    	    }
    	    /*
    	    * Check for correct node-type.
    	    */
    	    step = comp->steps[stepNr];
    	    if (step.nodeType != nodeType) {
    		if (step.nodeType == XML_ATTRIBUTE_NODE) {
    		    /*
    		    * Block this expression for deeper evaluation.
    		    */
    		    if ((comp->flags & XML_STREAM_DESC) == 0)
    			stream->blockLevel = stream->level +1;
    		    goto next_state;
    		} else if (step.nodeType != XML_STREAM_ANY_NODE)
    		    goto next_state;
    	    }
    	    /*
    	    * Compare local/namespace-name.
    	    */
    	    match = 0;
    	    if (step.nodeType == XML_STREAM_ANY_NODE) {
    		match = 1;
    	    } else if (step.name == NULL) {
    		if (step.ns == NULL) {
    		    /*
    		    * This lets through all elements/attributes.
    		    */
    		    match = 1;
    		} else if (ns != NULL)
    		    match = xmlStrEqual(step.ns, ns);
    	    } else if (((step.ns != NULL) == (ns != NULL)) &&
    		(name != NULL) &&
    		(step.name[0] == name[0]) &&
    		xmlStrEqual(step.name, name) &&
    		((step.ns == ns) || xmlStrEqual(step.ns, ns)))
    	    {
    		match = 1;
    	    }
    #if 0
    /*
    * TODO: Pointer comparison won't work, since not guaranteed that the given
    *  values are in the same dict; especially if it's the namespace name,
    *  normally coming from ns->href. We need a namespace dict mechanism !
    */
    	    } else if (comp->dict) {
    		if (step.name == NULL) {
    		    if (step.ns == NULL)
    			match = 1;
    		    else
    			match = (step.ns == ns);
    		} else {
    		    match = ((step.name == name) && (step.ns == ns));
    		}
    #endif /* if 0 ------------------------------------------------------- */
    	    if (match) {
    		final = step.flags & XML_STREAM_STEP_FINAL;
    		if (desc) {
    		    if (final) {
    			ret = 1;
    		    } else {
    			/* descending match create a new state */
    			xmlStreamCtxtAddState(stream, stepNr + 1,
    			                      stream->level + 1);
    		    }
    		} else {
    		    if (final) {
    			ret = 1;
    		    } else {
    			xmlStreamCtxtAddState(stream, stepNr + 1,
    			                      stream->level + 1);
    		    }
    		}
    		if ((ret != 1) && (step.flags & XML_STREAM_STEP_IN_SET)) {
    		    /*
    		    * Check if we have a special case like "foo/bar//.", where
    		    * "foo" is selected as well.
    		    */
    		    ret = 1;
    		}
    	    }
    	    if (((comp->flags & XML_STREAM_DESC) == 0) &&
    		((! match) || final))  {
    		/*
    		* Mark this expression as blocked for any evaluation at
    		* deeper levels. Note that this includes "/foo"
    		* expressions if the *pattern* behaviour is used.
    		*/
    		stream->blockLevel = stream->level +1;
    	    }
    next_state:
    	    i++;
    	}
    
    	stream->level++;
    
    	/*
    	* Re/enter the expression.
    	* Don't reenter if it's an absolute expression like "/foo",
    	*   except "//foo".
    	*/
    	step = comp->steps[0];
    	if (step.flags & XML_STREAM_STEP_ROOT)
    	    goto stream_next;
    
    	desc = step.flags & XML_STREAM_STEP_DESC;
    	if (stream->flags & XML_PATTERN_NOTPATTERN) {
    	    /*
    	    * Re/enter the expression if it is a "descendant" one,
    	    * or if we are at the 1st level of evaluation.
    	    */
    
    	    if (stream->level == 1) {
    		if (XML_STREAM_XS_IDC(stream)) {
    		    /*
    		    * XS-IDC: The missing "self::node()" will always
    		    * match the first given node.
    		    */
    		    goto stream_next;
    		} else
    		    goto compare;
    	    }
    	    /*
    	    * A "//" is always reentrant.
    	    */
    	    if (desc)
    		goto compare;
    
    	    /*
    	    * XS-IDC: Process the 2nd level, since the missing
    	    * "self::node()" is responsible for the 2nd level being
    	    * the real start level.
    	    */
    	    if ((stream->level == 2) && XML_STREAM_XS_IDC(stream))
    		goto compare;
    
    	    goto stream_next;
    	}
    
    compare:
    	/*
    	* Check expected node-type.
    	*/
    	if (step.nodeType != nodeType) {
    	    if (nodeType == XML_ATTRIBUTE_NODE)
    		goto stream_next;
    	    else if (step.nodeType != XML_STREAM_ANY_NODE)
    		goto stream_next;
    	}
    	/*
    	* Compare local/namespace-name.
    	*/
    	match = 0;
    	if (step.nodeType == XML_STREAM_ANY_NODE) {
    	    match = 1;
    	} else if (step.name == NULL) {
    	    if (step.ns == NULL) {
    		/*
    		* This lets through all elements/attributes.
    		*/
    		match = 1;
    	    } else if (ns != NULL)
    		match = xmlStrEqual(step.ns, ns);
    	} else if (((step.ns != NULL) == (ns != NULL)) &&
    	    (name != NULL) &&
    	    (step.name[0] == name[0]) &&
    	    xmlStrEqual(step.name, name) &&
    	    ((step.ns == ns) || xmlStrEqual(step.ns, ns)))
    	{
    	    match = 1;
    	}
    	final = step.flags & XML_STREAM_STEP_FINAL;
    	if (match) {
    	    if (final)
    		ret = 1;
    	    else
    		xmlStreamCtxtAddState(stream, 1, stream->level);
    	    if ((ret != 1) && (step.flags & XML_STREAM_STEP_IN_SET)) {
    		/*
    		* Check if we have a special case like "foo//.", where
    		* "foo" is selected as well.
    		*/
    		ret = 1;
    	    }
    	}
    	if (((comp->flags & XML_STREAM_DESC) == 0) &&
    	    ((! match) || final))  {
    	    /*
    	    * Mark this expression as blocked for any evaluation at
    	    * deeper levels.
    	    */
    	    stream->blockLevel = stream->level;
    	}
    
    stream_next:
            stream = stream->next;
        } /* while stream != NULL */
    
        if (err > 0)
            ret = -1;
    #ifdef DEBUG_STREAMING
        xmlDebugStreamCtxt(orig, ret);
    #endif
        return(ret);
    }
    
    /**
     * xmlStreamPush:
     * @stream: the stream context
     * @name: the current name
     * @ns: the namespace name
     *
     * Push new data onto the stream. NOTE: if the call xmlPatterncompile()
     * indicated a dictionary, then strings for name and ns will be expected
     * to come from the dictionary.
     * Both @name and @ns being NULL means the / i.e. the root of the document.
     * This can also act as a reset.
     * Otherwise the function will act as if it has been given an element-node.
     *
     * Returns: -1 in case of error, 1 if the current state in the stream is a
     *    match and 0 otherwise.
     */
    int
    xmlStreamPush(xmlStreamCtxtPtr stream,
                  const xmlChar *name, const xmlChar *ns) {
        return (xmlStreamPushInternal(stream, name, ns, (int) XML_ELEMENT_NODE));
    }
    
    /**
     * xmlStreamPushNode:
     * @stream: the stream context
     * @name: the current name
     * @ns: the namespace name
     * @nodeType: the type of the node being pushed
     *
     * Push new data onto the stream. NOTE: if the call xmlPatterncompile()
     * indicated a dictionary, then strings for name and ns will be expected
     * to come from the dictionary.
     * Both @name and @ns being NULL means the / i.e. the root of the document.
     * This can also act as a reset.
     * Different from xmlStreamPush() this function can be fed with nodes of type:
     * element-, attribute-, text-, cdata-section-, comment- and
     * processing-instruction-node.
     *
     * Returns: -1 in case of error, 1 if the current state in the stream is a
     *    match and 0 otherwise.
     */
    int
    xmlStreamPushNode(xmlStreamCtxtPtr stream,
    		  const xmlChar *name, const xmlChar *ns,
    		  int nodeType)
    {
        return (xmlStreamPushInternal(stream, name, ns,
    	nodeType));
    }
    
    /**
    * xmlStreamPushAttr:
    * @stream: the stream context
    * @name: the current name
    * @ns: the namespace name
    *
    * Push new attribute data onto the stream. NOTE: if the call xmlPatterncompile()
    * indicated a dictionary, then strings for name and ns will be expected
    * to come from the dictionary.
    * Both @name and @ns being NULL means the / i.e. the root of the document.
    * This can also act as a reset.
    * Otherwise the function will act as if it has been given an attribute-node.
    *
    * Returns: -1 in case of error, 1 if the current state in the stream is a
    *    match and 0 otherwise.
    */
    int
    xmlStreamPushAttr(xmlStreamCtxtPtr stream,
    		  const xmlChar *name, const xmlChar *ns) {
        return (xmlStreamPushInternal(stream, name, ns, (int) XML_ATTRIBUTE_NODE));
    }
    
    /**
     * xmlStreamPop:
     * @stream: the stream context
     *
     * push one level from the stream.
     *
     * Returns: -1 in case of error, 0 otherwise.
     */
    int
    xmlStreamPop(xmlStreamCtxtPtr stream) {
        int i, lev;
    
        if (stream == NULL)
            return(-1);
        while (stream != NULL) {
    	/*
    	* Reset block-level.
    	*/
    	if (stream->blockLevel == stream->level)
    	    stream->blockLevel = -1;
    
    	/*
    	 *  stream->level can be zero when XML_FINAL_IS_ANY_NODE is set
    	 *  (see the thread at
    	 *  http://mail.gnome.org/archives/xslt/2008-July/msg00027.html)
    	 */
    	if (stream->level)
    	    stream->level--;
    	/*
    	 * Check evolution of existing states
    	 */
    	for (i = stream->nbState -1; i >= 0; i--) {
    	    /* discard obsoleted states */
    	    lev = stream->states[(2 * i) + 1];
    	    if (lev > stream->level)
    		stream->nbState--;
    	    if (lev <= stream->level)
    		break;
    	}
    	stream = stream->next;
        }
        return(0);
    }
    
    /**
     * xmlStreamWantsAnyNode:
     * @streamCtxt: the stream context
     *
     * Query if the streaming pattern additionally needs to be fed with
     * text-, cdata-section-, comment- and processing-instruction-nodes.
     * If the result is 0 then only element-nodes and attribute-nodes
     * need to be pushed.
     *
     * Returns: 1 in case of need of nodes of the above described types,
     *          0 otherwise. -1 on API errors.
     */
    int
    xmlStreamWantsAnyNode(xmlStreamCtxtPtr streamCtxt)
    {
        if (streamCtxt == NULL)
    	return(-1);
        while (streamCtxt != NULL) {
    	if (streamCtxt->comp->flags & XML_STREAM_FINAL_IS_ANY_NODE)
    	    return(1);
    	streamCtxt = streamCtxt->next;
        }
        return(0);
    }
    
    /************************************************************************
     *									*
     *			The public interfaces				*
     *									*
     ************************************************************************/
    
    /**
     * xmlPatterncompile:
     * @pattern: the pattern to compile
     * @dict: an optional dictionary for interned strings
     * @flags: compilation flags, see xmlPatternFlags
     * @namespaces: the prefix definitions, array of [URI, prefix] or NULL
     *
     * Compile a pattern.
     *
     * Returns the compiled form of the pattern or NULL in case of error
     */
    xmlPatternPtr
    xmlPatterncompile(const xmlChar *pattern, xmlDict *dict, int flags,
                      const xmlChar **namespaces) {
        xmlPatternPtr ret = NULL, cur;
        xmlPatParserContextPtr ctxt = NULL;
        const xmlChar *or, *start;
        xmlChar *tmp = NULL;
        int type = 0;
        int streamable = 1;
    
        if (pattern == NULL)
            return(NULL);
    
        start = pattern;
        or = start;
        while (*or != 0) {
    	tmp = NULL;
    	while ((*or != 0) && (*or != '|')) or++;
            if (*or == 0)
    	    ctxt = xmlNewPatParserContext(start, dict, namespaces);
    	else {
    	    tmp = xmlStrndup(start, or - start);
    	    if (tmp != NULL) {
    		ctxt = xmlNewPatParserContext(tmp, dict, namespaces);
    	    }
    	    or++;
    	}
    	if (ctxt == NULL) goto error;
    	cur = xmlNewPattern();
    	if (cur == NULL) goto error;
    	/*
    	* Assign string dict.
    	*/
    	if (dict) {
    	    cur->dict = dict;
    	    xmlDictReference(dict);
    	}
    	if (ret == NULL)
    	    ret = cur;
    	else {
    	    cur->next = ret->next;
    	    ret->next = cur;
    	}
    	cur->flags = flags;
    	ctxt->comp = cur;
    
    	if (XML_STREAM_XS_IDC(cur))
    	    xmlCompileIDCXPathPath(ctxt);
    	else
    	    xmlCompilePathPattern(ctxt);
    	if (ctxt->error != 0)
    	    goto error;
    	xmlFreePatParserContext(ctxt);
    	ctxt = NULL;
    
    
            if (streamable) {
    	    if (type == 0) {
    	        type = cur->flags & (PAT_FROM_ROOT | PAT_FROM_CUR);
    	    } else if (type == PAT_FROM_ROOT) {
    	        if (cur->flags & PAT_FROM_CUR)
    		    streamable = 0;
    	    } else if (type == PAT_FROM_CUR) {
    	        if (cur->flags & PAT_FROM_ROOT)
    		    streamable = 0;
    	    }
    	}
    	if (streamable)
    	    xmlStreamCompile(cur);
    	if (xmlReversePattern(cur) < 0)
    	    goto error;
    	if (tmp != NULL) {
    	    xmlFree(tmp);
    	    tmp = NULL;
    	}
    	start = or;
        }
        if (streamable == 0) {
            cur = ret;
    	while (cur != NULL) {
    	    if (cur->stream != NULL) {
    		xmlFreeStreamComp(cur->stream);
    		cur->stream = NULL;
    	    }
    	    cur = cur->next;
    	}
        }
    
        return(ret);
    error:
        if (ctxt != NULL) xmlFreePatParserContext(ctxt);
        if (ret != NULL) xmlFreePattern(ret);
        if (tmp != NULL) xmlFree(tmp);
        return(NULL);
    }
    
    /**
     * xmlPatternMatch:
     * @comp: the precompiled pattern
     * @node: a node
     *
     * Test whether the node matches the pattern
     *
     * Returns 1 if it matches, 0 if it doesn't and -1 in case of failure
     */
    int
    xmlPatternMatch(xmlPatternPtr comp, xmlNodePtr node)
    {
        int ret = 0;
    
        if ((comp == NULL) || (node == NULL))
            return(-1);
    
        while (comp != NULL) {
            ret = xmlPatMatch(comp, node);
    	if (ret != 0)
    	    return(ret);
    	comp = comp->next;
        }
        return(ret);
    }
    
    /**
     * xmlPatternGetStreamCtxt:
     * @comp: the precompiled pattern
     *
     * Get a streaming context for that pattern
     * Use xmlFreeStreamCtxt to free the context.
     *
     * Returns a pointer to the context or NULL in case of failure
     */
    xmlStreamCtxtPtr
    xmlPatternGetStreamCtxt(xmlPatternPtr comp)
    {
        xmlStreamCtxtPtr ret = NULL, cur;
    
        if ((comp == NULL) || (comp->stream == NULL))
            return(NULL);
    
        while (comp != NULL) {
            if (comp->stream == NULL)
    	    goto failed;
    	cur = xmlNewStreamCtxt(comp->stream);
    	if (cur == NULL)
    	    goto failed;
    	if (ret == NULL)
    	    ret = cur;
    	else {
    	    cur->next = ret->next;
    	    ret->next = cur;
    	}
    	cur->flags = comp->flags;
    	comp = comp->next;
        }
        return(ret);
    failed:
        xmlFreeStreamCtxt(ret);
        return(NULL);
    }
    
    /**
     * xmlPatternStreamable:
     * @comp: the precompiled pattern
     *
     * Check if the pattern is streamable i.e. xmlPatternGetStreamCtxt()
     * should work.
     *
     * Returns 1 if streamable, 0 if not and -1 in case of error.
     */
    int
    xmlPatternStreamable(xmlPatternPtr comp) {
        if (comp == NULL)
            return(-1);
        while (comp != NULL) {
            if (comp->stream == NULL)
    	    return(0);
    	comp = comp->next;
        }
        return(1);
    }
    
    /**
     * xmlPatternMaxDepth:
     * @comp: the precompiled pattern
     *
     * Check the maximum depth reachable by a pattern
     *
     * Returns -2 if no limit (using //), otherwise the depth,
     *         and -1 in case of error
     */
    int
    xmlPatternMaxDepth(xmlPatternPtr comp) {
        int ret = 0, i;
        if (comp == NULL)
            return(-1);
        while (comp != NULL) {
            if (comp->stream == NULL)
    	    return(-1);
    	for (i = 0;i < comp->stream->nbStep;i++)
    	    if (comp->stream->steps[i].flags & XML_STREAM_STEP_DESC)
    	        return(-2);
    	if (comp->stream->nbStep > ret)
    	    ret = comp->stream->nbStep;
    	comp = comp->next;
        }
        return(ret);
    }
    
    /**
     * xmlPatternMinDepth:
     * @comp: the precompiled pattern
     *
     * Check the minimum depth reachable by a pattern, 0 mean the / or . are
     * part of the set.
     *
     * Returns -1 in case of error otherwise the depth,
     *
     */
    int
    xmlPatternMinDepth(xmlPatternPtr comp) {
        int ret = 12345678;
        if (comp == NULL)
            return(-1);
        while (comp != NULL) {
            if (comp->stream == NULL)
    	    return(-1);
    	if (comp->stream->nbStep < ret)
    	    ret = comp->stream->nbStep;
    	if (ret == 0)
    	    return(0);
    	comp = comp->next;
        }
        return(ret);
    }
    
    /**
     * xmlPatternFromRoot:
     * @comp: the precompiled pattern
     *
     * Check if the pattern must be looked at from the root.
     *
     * Returns 1 if true, 0 if false and -1 in case of error
     */
    int
    xmlPatternFromRoot(xmlPatternPtr comp) {
        if (comp == NULL)
            return(-1);
        while (comp != NULL) {
            if (comp->stream == NULL)
    	    return(-1);
    	if (comp->flags & PAT_FROM_ROOT)
    	    return(1);
    	comp = comp->next;
        }
        return(0);
    
    }
    
    #define bottom_pattern
    #include "elfgcchack.h"
    #endif /* LIBXML_PATTERN_ENABLED */