xmlreader.c

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    if ((reader == NULL) || (reader->ctxt == NULL))
	return(-1);
    if (reader->ctxt->wellFormed != 1)
	return(-1);

    if ((reader->node == NULL) || (reader->node->type == XML_ELEMENT_NODE))
	return(0);
    TODO
    return(0);
}

/**
 * xmlTextReaderReadBinHex:
 * @reader:  the xmlTextReaderPtr used
 * @array:  a byte array to store the content.
 * @offset:  the zero-based index into array where the method should
 *           begin to write.
 * @len:  the number of bytes to write.
 *
 * Reads and decodes the BinHex encoded contents of an element and
 * stores the result in a byte buffer.
 *
 * Returns the number of bytes written to array, or zero if the current
 *         instance is not positioned on an element or -1 in case of error.
 */
int
xmlTextReaderReadBinHex(xmlTextReaderPtr reader,
                        unsigned char *array ATTRIBUTE_UNUSED,
	                int offset ATTRIBUTE_UNUSED,
			int len ATTRIBUTE_UNUSED) {
    if ((reader == NULL) || (reader->ctxt == NULL))
	return(-1);
    if (reader->ctxt->wellFormed != 1)
	return(-1);

    if ((reader->node == NULL) || (reader->node->type == XML_ELEMENT_NODE))
	return(0);
    TODO
    return(0);
}
#endif

/************************************************************************
 *									*
 *			Operating on a preparsed tree			*
 *									*
 ************************************************************************/
static int
xmlTextReaderNextTree(xmlTextReaderPtr reader)
{
    if (reader == NULL)
        return(-1);

    if (reader->state == XML_TEXTREADER_END)
        return(0);

    if (reader->node == NULL) {
        if (reader->doc->children == NULL) {
            reader->state = XML_TEXTREADER_END;
            return(0);
        }

        reader->node = reader->doc->children;
        reader->state = XML_TEXTREADER_START;
        return(1);
    }

    if (reader->state != XML_TEXTREADER_BACKTRACK) {
        if (reader->node->children != 0) {
            reader->node = reader->node->children;
            reader->depth++;
            reader->state = XML_TEXTREADER_START;
            return(1);
        }

        if ((reader->node->type == XML_ELEMENT_NODE) ||
            (reader->node->type == XML_ATTRIBUTE_NODE)) {
            reader->state = XML_TEXTREADER_BACKTRACK;
            return(1);
        }
    }

    if (reader->node->next != 0) {
        reader->node = reader->node->next;
        reader->state = XML_TEXTREADER_START;
        return(1);
    }

    if (reader->node->parent != 0) {
        if (reader->node->parent->type == XML_DOCUMENT_NODE) {
            reader->state = XML_TEXTREADER_END;
            return(0);
        }

        reader->node = reader->node->parent;
        reader->depth--;
        reader->state = XML_TEXTREADER_BACKTRACK;
        return(1);
    }

    reader->state = XML_TEXTREADER_END;

    return(1);
}

/**
 * xmlTextReaderReadTree:
 * @reader:  the xmlTextReaderPtr used
 *
 *  Moves the position of the current instance to the next node in
 *  the stream, exposing its properties.
 *
 *  Returns 1 if the node was read successfully, 0 if there is no more
 *          nodes to read, or -1 in case of error
 */
static int
xmlTextReaderReadTree(xmlTextReaderPtr reader) {
    if (reader->state == XML_TEXTREADER_END)
        return(0);

next_node:
    if (reader->node == NULL) {
        if (reader->doc->children == NULL) {
            reader->state = XML_TEXTREADER_END;
            return(0);
        }

        reader->node = reader->doc->children;
        reader->state = XML_TEXTREADER_START;
        goto found_node;
    }

    if ((reader->state != XML_TEXTREADER_BACKTRACK) &&
        (reader->node->type != XML_DTD_NODE) &&
        (reader->node->type != XML_XINCLUDE_START) &&
	(reader->node->type != XML_ENTITY_REF_NODE)) {
        if (reader->node->children != NULL) {
            reader->node = reader->node->children;
            reader->depth++;
            reader->state = XML_TEXTREADER_START;
            goto found_node;
        }

        if (reader->node->type == XML_ATTRIBUTE_NODE) {
            reader->state = XML_TEXTREADER_BACKTRACK;
            goto found_node;
        }
    }

    if (reader->node->next != NULL) {
        reader->node = reader->node->next;
        reader->state = XML_TEXTREADER_START;
        goto found_node;
    }

    if (reader->node->parent != NULL) {
        if ((reader->node->parent->type == XML_DOCUMENT_NODE) ||
	    (reader->node->parent->type == XML_HTML_DOCUMENT_NODE)) {
            reader->state = XML_TEXTREADER_END;
            return(0);
        }

        reader->node = reader->node->parent;
        reader->depth--;
        reader->state = XML_TEXTREADER_BACKTRACK;
        goto found_node;
    }

    reader->state = XML_TEXTREADER_END;

found_node:
    if ((reader->node->type == XML_XINCLUDE_START) ||
        (reader->node->type == XML_XINCLUDE_END))
	goto next_node;

    return(1);
}

/**
 * xmlTextReaderNextSibling:
 * @reader:  the xmlTextReaderPtr used
 *
 * Skip to the node following the current one in document order while
 * avoiding the subtree if any.
 * Currently implemented only for Readers built on a document
 *
 * Returns 1 if the node was read successfully, 0 if there is no more
 *          nodes to read, or -1 in case of error
 */
int
xmlTextReaderNextSibling(xmlTextReaderPtr reader) {
    if (reader == NULL)
        return(-1);
    if (reader->doc == NULL) {
        /* TODO */
	return(-1);
    }

    if (reader->state == XML_TEXTREADER_END)
        return(0);

    if (reader->node == NULL)
        return(xmlTextReaderNextTree(reader));

    if (reader->node->next != NULL) {
        reader->node = reader->node->next;
        reader->state = XML_TEXTREADER_START;
        return(1);
    }

    return(0);
}

/************************************************************************
 *									*
 *			Constructor and destructors			*
 *									*
 ************************************************************************/
/**
 * xmlNewTextReader:
 * @input: the xmlParserInputBufferPtr used to read data
 * @URI: the URI information for the source if available
 *
 * Create an xmlTextReader structure fed with @input
 *
 * Returns the new xmlTextReaderPtr or NULL in case of error
 */
xmlTextReaderPtr
xmlNewTextReader(xmlParserInputBufferPtr input, const char *URI) {
    xmlTextReaderPtr ret;

    if (input == NULL)
	return(NULL);
    ret = xmlMalloc(sizeof(xmlTextReader));
    if (ret == NULL) {
        xmlGenericError(xmlGenericErrorContext,
		"xmlNewTextReader : malloc failed\n");
	return(NULL);
    }
    memset(ret, 0, sizeof(xmlTextReader));
    ret->doc = NULL;
    ret->entTab = NULL;
    ret->entMax = 0;
    ret->entNr = 0;
    ret->input = input;
    ret->buffer = xmlBufferCreateSize(100);
    if (ret->buffer == NULL) {
        xmlFree(ret);
        xmlGenericError(xmlGenericErrorContext,
		"xmlNewTextReader : malloc failed\n");
	return(NULL);
    }
    ret->sax = (xmlSAXHandler *) xmlMalloc(sizeof(xmlSAXHandler));
    if (ret->sax == NULL) {
	xmlBufferFree(ret->buffer);
	xmlFree(ret);
        xmlGenericError(xmlGenericErrorContext,
		"xmlNewTextReader : malloc failed\n");
	return(NULL);
    }
    xmlSAXVersion(ret->sax, 2);
    ret->startElement = ret->sax->startElement;
    ret->sax->startElement = xmlTextReaderStartElement;
    ret->endElement = ret->sax->endElement;
    ret->sax->endElement = xmlTextReaderEndElement;
#ifdef LIBXML_SAX1_ENABLED
    if (ret->sax->initialized == XML_SAX2_MAGIC) {
#endif /* LIBXML_SAX1_ENABLED */
	ret->startElementNs = ret->sax->startElementNs;
	ret->sax->startElementNs = xmlTextReaderStartElementNs;
	ret->endElementNs = ret->sax->endElementNs;
	ret->sax->endElementNs = xmlTextReaderEndElementNs;
#ifdef LIBXML_SAX1_ENABLED
    } else {
	ret->startElementNs = NULL;
	ret->endElementNs = NULL;
    }
#endif /* LIBXML_SAX1_ENABLED */
    ret->characters = ret->sax->characters;
    ret->sax->characters = xmlTextReaderCharacters;
    ret->sax->ignorableWhitespace = xmlTextReaderCharacters;
    ret->cdataBlock = ret->sax->cdataBlock;
    ret->sax->cdataBlock = xmlTextReaderCDataBlock;

    ret->mode = XML_TEXTREADER_MODE_INITIAL;
    ret->node = NULL;
    ret->curnode = NULL;
    if (ret->input->buffer->use < 4) {
	xmlParserInputBufferRead(input, 4);
    }
    if (ret->input->buffer->use >= 4) {
	ret->ctxt = xmlCreatePushParserCtxt(ret->sax, NULL,
			(const char *) ret->input->buffer->content, 4, URI);
	ret->base = 0;
	ret->cur = 4;
    } else {
	ret->ctxt = xmlCreatePushParserCtxt(ret->sax, NULL, NULL, 0, URI);
	ret->base = 0;
	ret->cur = 0;
    }
    
    if (ret->ctxt == NULL) {
        xmlGenericError(xmlGenericErrorContext,
		"xmlNewTextReader : malloc failed\n");
	xmlBufferFree(ret->buffer);
	xmlFree(ret->sax);
	xmlFree(ret);
	return(NULL);
    }
    ret->ctxt->parseMode = XML_PARSE_READER;
    ret->ctxt->_private = ret;
    ret->ctxt->linenumbers = 1;
    ret->ctxt->dictNames = 1;
    ret->allocs = XML_TEXTREADER_CTXT;
    /*
     * use the parser dictionnary to allocate all elements and attributes names
     */
    ret->ctxt->docdict = 1;
    ret->dict = ret->ctxt->dict;
#ifdef LIBXML_XINCLUDE_ENABLED
    ret->xinclude = 0;
#endif
#ifdef LIBXML_PATTERN_ENABLED
    ret->patternMax = 0;
    ret->patternTab = NULL;
#endif
    return(ret);
}

/**
 * xmlNewTextReaderFilename:
 * @URI: the URI of the resource to process
 *
 * Create an xmlTextReader structure fed with the resource at @URI
 *
 * Returns the new xmlTextReaderPtr or NULL in case of error
 */
xmlTextReaderPtr
xmlNewTextReaderFilename(const char *URI) {
    xmlParserInputBufferPtr input;
    xmlTextReaderPtr ret;
    char *directory = NULL;

    input = xmlParserInputBufferCreateFilename(URI, XML_CHAR_ENCODING_NONE);
    if (input == NULL)
	return(NULL);
    ret = xmlNewTextReader(input, URI);
    if (ret == NULL) {
	xmlFreeParserInputBuffer(input);
	return(NULL);
    }
    ret->allocs |= XML_TEXTREADER_INPUT;
    if (ret->ctxt->directory == NULL)
        directory = xmlParserGetDirectory(URI);
    if ((ret->ctxt->directory == NULL) && (directory != NULL))
        ret->ctxt->directory = (char *) xmlStrdup((xmlChar *) directory);
    if (directory != NULL)
	xmlFree(directory);
    return(ret);
}

/**
 * xmlFreeTextReader:
 * @reader:  the xmlTextReaderPtr
 *
 * Deallocate all the resources associated to the reader
 */
void
xmlFreeTextReader(xmlTextReaderPtr reader) {
    if (reader == NULL)
	return;
#ifdef LIBXML_SCHEMAS_ENABLED
    if (reader->rngSchemas != NULL) {
	xmlRelaxNGFree(reader->rngSchemas);
	reader->rngSchemas = NULL;
    }
    if (reader->rngValidCtxt != NULL) {
	xmlRelaxNGFreeValidCtxt(reader->rngValidCtxt);
	reader->rngValidCtxt = NULL;
    }
    if (reader->xsdPlug != NULL) {
	xmlSchemaSAXUnplug(reader->xsdPlug);
	reader->xsdPlug = NULL;
    }
    if (reader->xsdValidCtxt != NULL) {
	xmlSchemaFreeValidCtxt(reader->xsdValidCtxt);
	reader->xsdValidCtxt = NULL;
    }
    if (reader->xsdSchemas != NULL) {
	xmlSchemaFree(reader->xsdSchemas);
	reader->xsdSchemas = NULL;
    }
#endif
#ifdef LIBXML_XINCLUDE_ENABLED
    if (reader->xincctxt != NULL)
	xmlXIncludeFreeContext(reader->xincctxt);
#endif
#ifdef LIBXML_PATTERN_ENABLED
    if (reader->patternTab != NULL) {
        int i;
	for (i = 0;i < reader->patternNr;i++) {
	    if (reader->patternTab[i] != NULL)
	        xmlFreePattern(reader->patternTab[i]);
	}
	xmlFree(reader->patternTab);
    }
#endif
    if (reader->ctxt != NULL) {
        if (reader->dict == reader->ctxt->dict)
	    reader->dict = NULL;
	if (reader->ctxt->myDoc != NULL) {
	    if (reader->preserve == 0)
		xmlTextReaderFreeDoc(reader, reader->ctxt->myDoc);
	    reader->ctxt->myDoc = NULL;
	}
	if ((reader->ctxt->vctxt.vstateTab != NULL) &&
	    (reader->ctxt->vctxt.vstateMax > 0)){
	    xmlFree(reader->ctxt->vctxt.vstateTab);
	    reader->ctxt->vctxt.vstateTab = 0;
	    reader->ctxt->vctxt.vstateMax = 0;
	}
	if (reader->allocs & XML_TEXTREADER_CTXT)
	    xmlFreeParserCtxt(reader->ctxt);
    }
    if (reader->sax != NULL)
	xmlFree(reader->sax);
    if ((reader->input != NULL)  && (reader->allocs & XML_TEXTREADER_INPUT))
	xmlFreeParserInputBuffer(reader->input);
    if (reader->faketext != NULL) {
	xmlFreeNode(reader->faketext);
    }
    if (reader->buffer != NULL)
        xmlBufferFree(reader->buffer);
    if (reader->entTab != NULL)
	xmlFree(reader->en