xpath.c

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    cur->last = -1;
#ifdef DEBUG_EVAL_COUNTS
    cur->nb = 0;
#endif
    return(cur);
}

/**
 * xmlXPathFreeCompExpr:
 * @comp:  an XPATH comp
 *
 * Free up the memory allocated by @comp
 */
void
xmlXPathFreeCompExpr(xmlXPathCompExprPtr comp)
{
    xmlXPathStepOpPtr op;
    int i;

    if (comp == NULL)
        return;
    if (comp->dict == NULL) {
	for (i = 0; i < comp->nbStep; i++) {
	    op = &comp->steps[i];
	    if (op->value4 != NULL) {
		if (op->op == XPATH_OP_VALUE)
		    xmlXPathFreeObject(op->value4);
		else
		    xmlFree(op->value4);
	    }
	    if (op->value5 != NULL)
		xmlFree(op->value5);
	}
    } else {
	for (i = 0; i < comp->nbStep; i++) {
	    op = &comp->steps[i];
	    if (op->value4 != NULL) {
		if (op->op == XPATH_OP_VALUE)
		    xmlXPathFreeObject(op->value4);
	    }
	}
        xmlDictFree(comp->dict);
    }
    if (comp->steps != NULL) {
        xmlFree(comp->steps);
    }
#ifdef DEBUG_EVAL_COUNTS
    if (comp->string != NULL) {
        xmlFree(comp->string);
    }
#endif
#ifdef XPATH_STREAMING
    if (comp->stream != NULL) {
        xmlFreePatternList(comp->stream);
    }
#endif
    if (comp->expr != NULL) {
        xmlFree(comp->expr);
    }

    xmlFree(comp);
}

/**
 * xmlXPathCompExprAdd:
 * @comp:  the compiled expression
 * @ch1: first child index
 * @ch2: second child index
 * @op:  an op
 * @value:  the first int value
 * @value2:  the second int value
 * @value3:  the third int value
 * @value4:  the first string value
 * @value5:  the second string value
 *
 * Add a step to an XPath Compiled Expression
 *
 * Returns -1 in case of failure, the index otherwise
 */
static int
xmlXPathCompExprAdd(xmlXPathCompExprPtr comp, int ch1, int ch2,
   xmlXPathOp op, int value,
   int value2, int value3, void *value4, void *value5) {
    if (comp->nbStep >= comp->maxStep) {
	xmlXPathStepOp *real;

	comp->maxStep *= 2;
	real = (xmlXPathStepOp *) xmlRealloc(comp->steps,
		                      comp->maxStep * sizeof(xmlXPathStepOp));
	if (real == NULL) {
	    comp->maxStep /= 2;
	    xmlXPathErrMemory(NULL, "adding step\n");
	    return(-1);
	}
	comp->steps = real;
    }
    comp->last = comp->nbStep;
    comp->steps[comp->nbStep].ch1 = ch1;
    comp->steps[comp->nbStep].ch2 = ch2;
    comp->steps[comp->nbStep].op = op;
    comp->steps[comp->nbStep].value = value;
    comp->steps[comp->nbStep].value2 = value2;
    comp->steps[comp->nbStep].value3 = value3;
    if ((comp->dict != NULL) &&
        ((op == XPATH_OP_FUNCTION) || (op == XPATH_OP_VARIABLE) ||
	 (op == XPATH_OP_COLLECT))) {
        if (value4 != NULL) {
	    comp->steps[comp->nbStep].value4 = (xmlChar *)
	        (void *)xmlDictLookup(comp->dict, value4, -1);
	    xmlFree(value4);
	} else
	    comp->steps[comp->nbStep].value4 = NULL;
        if (value5 != NULL) {
	    comp->steps[comp->nbStep].value5 = (xmlChar *)
	        (void *)xmlDictLookup(comp->dict, value5, -1);
	    xmlFree(value5);
	} else
	    comp->steps[comp->nbStep].value5 = NULL;
    } else {
	comp->steps[comp->nbStep].value4 = value4;
	comp->steps[comp->nbStep].value5 = value5;
    }
    comp->steps[comp->nbStep].cache = NULL;
    return(comp->nbStep++);
}

/**
 * xmlXPathCompSwap:
 * @comp:  the compiled expression
 * @op: operation index
 *
 * Swaps 2 operations in the compiled expression
 */
static void
xmlXPathCompSwap(xmlXPathStepOpPtr op) {
    int tmp;

#ifndef LIBXML_THREAD_ENABLED
    /*
     * Since this manipulates possibly shared variables, this is
     * disabled if one detects that the library is used in a multithreaded
     * application
     */
    if (xmlXPathDisableOptimizer)
	return;
#endif

    tmp = op->ch1;
    op->ch1 = op->ch2;
    op->ch2 = tmp;
}

#define PUSH_FULL_EXPR(op, op1, op2, val, val2, val3, val4, val5)	\
    xmlXPathCompExprAdd(ctxt->comp, (op1), (op2),			\
	                (op), (val), (val2), (val3), (val4), (val5))
#define PUSH_LONG_EXPR(op, val, val2, val3, val4, val5)			\
    xmlXPathCompExprAdd(ctxt->comp, ctxt->comp->last, -1,		\
	                (op), (val), (val2), (val3), (val4), (val5))

#define PUSH_LEAVE_EXPR(op, val, val2) 					\
xmlXPathCompExprAdd(ctxt->comp, -1, -1, (op), (val), (val2), 0 ,NULL ,NULL)

#define PUSH_UNARY_EXPR(op, ch, val, val2) 				\
xmlXPathCompExprAdd(ctxt->comp, (ch), -1, (op), (val), (val2), 0 ,NULL ,NULL)

#define PUSH_BINARY_EXPR(op, ch1, ch2, val, val2) 			\
xmlXPathCompExprAdd(ctxt->comp, (ch1), (ch2), (op),			\
			(val), (val2), 0 ,NULL ,NULL)

/************************************************************************
 *									*
 * 		Debugging related functions				*
 *									*
 ************************************************************************/

#define STRANGE 							\
    xmlGenericError(xmlGenericErrorContext,				\
	    "Internal error at %s:%d\n",				\
            __FILE__, __LINE__);

#ifdef LIBXML_DEBUG_ENABLED
static void
xmlXPathDebugDumpNode(FILE *output, xmlNodePtr cur, int depth) {
    int i;
    char shift[100];

    for (i = 0;((i < depth) && (i < 25));i++)
        shift[2 * i] = shift[2 * i + 1] = ' ';
    shift[2 * i] = shift[2 * i + 1] = 0;
    if (cur == NULL) {
	fprintf(output, shift);
	fprintf(output, "Node is NULL !\n");
	return;
        
    }

    if ((cur->type == XML_DOCUMENT_NODE) ||
	     (cur->type == XML_HTML_DOCUMENT_NODE)) {
	fprintf(output, shift);
	fprintf(output, " /\n");
    } else if (cur->type == XML_ATTRIBUTE_NODE)
	xmlDebugDumpAttr(output, (xmlAttrPtr)cur, depth);
    else
	xmlDebugDumpOneNode(output, cur, depth);
}
static void
xmlXPathDebugDumpNodeList(FILE *output, xmlNodePtr cur, int depth) {
    xmlNodePtr tmp;
    int i;
    char shift[100];

    for (i = 0;((i < depth) && (i < 25));i++)
        shift[2 * i] = shift[2 * i + 1] = ' ';
    shift[2 * i] = shift[2 * i + 1] = 0;
    if (cur == NULL) {
	fprintf(output, shift);
	fprintf(output, "Node is NULL !\n");
	return;
        
    }

    while (cur != NULL) {
	tmp = cur;
	cur = cur->next;
	xmlDebugDumpOneNode(output, tmp, depth);
    }
}

static void
xmlXPathDebugDumpNodeSet(FILE *output, xmlNodeSetPtr cur, int depth) {
    int i;
    char shift[100];

    for (i = 0;((i < depth) && (i < 25));i++)
        shift[2 * i] = shift[2 * i + 1] = ' ';
    shift[2 * i] = shift[2 * i + 1] = 0;

    if (cur == NULL) {
	fprintf(output, shift);
	fprintf(output, "NodeSet is NULL !\n");
	return;
        
    }

    if (cur != NULL) {
	fprintf(output, "Set contains %d nodes:\n", cur->nodeNr);
	for (i = 0;i < cur->nodeNr;i++) {
	    fprintf(output, shift);
	    fprintf(output, "%d", i + 1);
	    xmlXPathDebugDumpNode(output, cur->nodeTab[i], depth + 1);
	}
    }
}

static void
xmlXPathDebugDumpValueTree(FILE *output, xmlNodeSetPtr cur, int depth) {
    int i;
    char shift[100];

    for (i = 0;((i < depth) && (i < 25));i++)
        shift[2 * i] = shift[2 * i + 1] = ' ';
    shift[2 * i] = shift[2 * i + 1] = 0;

    if ((cur == NULL) || (cur->nodeNr == 0) || (cur->nodeTab[0] == NULL)) {
	fprintf(output, shift);
	fprintf(output, "Value Tree is NULL !\n");
	return;
        
    }

    fprintf(output, shift);
    fprintf(output, "%d", i + 1);
    xmlXPathDebugDumpNodeList(output, cur->nodeTab[0]->children, depth + 1);
}
#if defined(LIBXML_XPTR_ENABLED)
static void
xmlXPathDebugDumpLocationSet(FILE *output, xmlLocationSetPtr cur, int depth) {
    int i;
    char shift[100];

    for (i = 0;((i < depth) && (i < 25));i++)
        shift[2 * i] = shift[2 * i + 1] = ' ';
    shift[2 * i] = shift[2 * i + 1] = 0;

    if (cur == NULL) {
	fprintf(output, shift);
	fprintf(output, "LocationSet is NULL !\n");
	return;
        
    }

    for (i = 0;i < cur->locNr;i++) {
	fprintf(output, shift);
        fprintf(output, "%d : ", i + 1);
	xmlXPathDebugDumpObject(output, cur->locTab[i], depth + 1);
    }
}
#endif /* LIBXML_XPTR_ENABLED */

/**
 * xmlXPathDebugDumpObject:
 * @output:  the FILE * to dump the output
 * @cur:  the object to inspect
 * @depth:  indentation level
 *
 * Dump the content of the object for debugging purposes
 */
void
xmlXPathDebugDumpObject(FILE *output, xmlXPathObjectPtr cur, int depth) {
    int i;
    char shift[100];

    if (output == NULL) return;

    for (i = 0;((i < depth) && (i < 25));i++)
        shift[2 * i] = shift[2 * i + 1] = ' ';
    shift[2 * i] = shift[2 * i + 1] = 0;

    fprintf(output, shift);

    if (cur == NULL) {
        fprintf(output, "Object is empty (NULL)\n");
	return;
    }
    switch(cur->type) {
        case XPATH_UNDEFINED:
	    fprintf(output, "Object is uninitialized\n");
	    break;
        case XPATH_NODESET:
	    fprintf(output, "Object is a Node Set :\n");
	    xmlXPathDebugDumpNodeSet(output, cur->nodesetval, depth);
	    break;
	case XPATH_XSLT_TREE:
	    fprintf(output, "Object is an XSLT value tree :\n");
	    xmlXPathDebugDumpValueTree(output, cur->nodesetval, depth);
	    break;
        case XPATH_BOOLEAN:
	    fprintf(output, "Object is a Boolean : ");
	    if (cur->boolval) fprintf(output, "true\n");
	    else fprintf(output, "false\n");
	    break;
        case XPATH_NUMBER:
	    switch (xmlXPathIsInf(cur->floatval)) {
	    case 1:
		fprintf(output, "Object is a number : Infinity\n");
		break;
	    case -1:
		fprintf(output, "Object is a number : -Infinity\n");
		break;
	    default:
		if (xmlXPathIsNaN(cur->floatval)) {
		    fprintf(output, "Object is a number : NaN\n");
		} else if (cur->floatval == 0 && xmlXPathGetSign(cur->floatval) != 0) {
		    fprintf(output, "Object is a number : 0\n");
		} else {
		    fprintf(output, "Object is a number : %0g\n", cur->floatval);
		}
	    }
	    break;
        case XPATH_STRING:
	    fprintf(output, "Object is a string : ");
	    xmlDebugDumpString(output, cur->stringval);
	    fprintf(output, "\n");
	    break;
	case XPATH_POINT:
	    fprintf(output, "Object is a point : index %d in node", cur->index);
	    xmlXPathDebugDumpNode(output, (xmlNodePtr) cur->user, depth + 1);
	    fprintf(output, "\n");
	    break;
	case XPATH_RANGE:
	    if ((cur->user2 == NULL) ||
		((cur->user2 == cur->user) && (cur->index == cur->index2))) {
		fprintf(output, "Object is a collapsed range :\n");
		fprintf(output, shift);
		if (cur->index >= 0)
		    fprintf(output, "index %d in ", cur->index);
		fprintf(output, "node\n");
		xmlXPathDebugDumpNode(output, (xmlNodePtr) cur->user,
			              depth + 1);
	    } else  {
		fprintf(output, "Object is a range :\n");
		fprintf(output, shift);
		fprintf(output, "From ");
		if (cur->index >= 0)
		    fprintf(output, "index %d in ", cur->index);
		fprintf(output, "node\n");
		xmlXPathDebugDumpNode(output, (xmlNodePtr) cur->user,
			              depth + 1);
		fprintf(output, shift);
		fprintf(output, "To ");
		if (cur->index2 >= 0)
		    fprintf(output, "index %d in ", cur->index2);
		fprintf(output, "node\n");
		xmlXPathDebugDumpNode(output, (xmlNodePtr) cur->user2,
			              depth + 1);
		fprintf(output, "\n");
	    }
	    break;
	case XPATH_LOCATIONSET:
#if defined(LIBXML_XPTR_ENABLED)
	    fprintf(output, "Object is a Location Set:\n");
	    xmlXPathDebugDumpLocationSet(output,
		    (xmlLocationSetPtr) cur->user, depth);
#endif
	    break;
	case XPATH_USERS:
	    fprintf(output, "Object is user defined\n");
	    break;
    }
}

static void
xmlXPathDebugDumpStepOp(FILE *output, xmlXPathCompExprPtr comp,
	                     xmlXPathStepOpPtr op, int depth) {
    int i;
    char shift[100];

    for (i = 0;((i < depth) && (i < 25));i++)
        shift[2 * i] = shift[2 * i + 1] = ' ';
    shift[2 * i] = shift[2 * i + 1] = 0;

    fprintf(output, shift);
    if (op == NULL) {
	fprintf(output, "Step is NULL\n");
	return;
    }
    switch (op->op) {
        case XPATH_OP_END:
	    fprintf(output, "END"); break;
        case XPATH_OP_AND:
	    fprintf(output, "AND"); break;
        case XPATH_OP_OR:
	    fprintf(output, "OR"); break;
        case XPATH_OP_EQUAL:
	     if (op->value)
		 fprintf(output, "EQUAL =");
	     else
		 fprintf(output, "EQUAL !=");
	     break;
        case XPATH_OP_CMP:
	     if (op->value)
		 fprintf(output, "CMP <");
	     else
		 fprintf(output, "CMP >");
	     if (!op->value2)
		 fprintf(output, "=");
	     break;
        case XPATH_OP_PLUS:
	     if (op->value == 0)
		 fprintf(output, "PLUS -");
	     else if (op->value == 1)
		 fprintf(output, "PLUS +");
	     else if (op->value == 2)
		 fprintf(output, "PLUS unary -");
	     else if (op->value == 3)
		 fprintf(output, "PLUS unary - -");
	     break;
        case XPATH_OP_MULT:
	     if (op->value == 0)
		 fprintf(output, "MULT *");
	     else if (op->value == 1)
		 fprintf(output, "MULT div");
	     else
		 fprintf(output, "MULT mod");
	     break;
        case XPATH_OP_UNION:
	     fprintf(output, "UNION"); break;
        case XPATH_OP_ROOT:
	     fprintf(output, "ROOT"); break;
        case XPATH_OP_NODE:
	     fprintf(output, "NODE"); break;
        case XPATH_OP_RESET:
	     fprintf(output, "RESET"); break;
        case XPATH_OP_SORT:
	     fprintf(output, "SORT"); break;
        case XPATH_OP_COLLECT: {
	    xmlXPathAxisVal axis = (xmlXPathAxisVal)op->value;
	    xmlXPathTestVal test = (xmlXPathTestVal)op->value2;
	    xmlXPathTypeVal type = (xmlXPathTypeVal)op->value3;
	    const xmlChar *prefix = op->value4;
	    const xmlChar *name = op->value5;

	    fprintf(output, "COLLECT ");