example xml configuration file reading

/**
 * section: xmlReader
 * synopsis: Parse and validate an XML file with an xmlReader
 * purpose: Demonstrate the use of xmlReaderForFile() to parse an XML file
 *          validating the content in the process and activating options
 *          like entities substitution, and DTD attributes defaulting.
 *          (Note that the XMLReader functions require libxml2 version later
 *          than 2.6.)
 * usage: reader2 <valid_xml_filename>
 * test: reader2 test2.xml > reader1.tmp ; diff reader1.tmp reader1.res ; rm reader1.tmp
 * author: Daniel Veillard
 * copy: see Copyright for the status of this software.
 */

#include <stdio.h>
#include <libxml/xmlreader.h>

#ifdef LIBXML_READER_ENABLED

/**
 * processNode:
 * @reader: the xmlReader
 *
 * Dump information about the current node
 */
static void
processNode(xmlTextReaderPtr reader) {
    const xmlChar *name, *value;

    name = xmlTextReaderConstName(reader);
    if (name == NULL)
	name = BAD_CAST "--";

    value = xmlTextReaderConstValue(reader);

    printf("%d %d %s %d %d", 
	    xmlTextReaderDepth(reader),
	    xmlTextReaderNodeType(reader),
	    name,
	    xmlTextReaderIsEmptyElement(reader),
	    xmlTextReaderHasValue(reader));
    if (value == NULL)
	printf("\n");
    else {
        if (xmlStrlen(value) > 40)
            printf(" %.40s...\n", value);
        else
	    printf(" %s\n", value);
    }
}

/**
 * streamFile:
 * @filename: the file name to parse
 *
 * Parse, validate and print information about an XML file.
 */
static void
streamFile(const char *filename) {
    xmlTextReaderPtr reader;
    int ret;


    /*
     * Pass some special parsing options to activate DTD attribute defaulting,
     * entities substitution and DTD validation
     */
    reader = xmlReaderForFile(filename, NULL,
                 XML_PARSE_DTDATTR |  /* default DTD attributes */
		 XML_PARSE_NOENT |    /* substitute entities */
		 XML_PARSE_DTDVALID); /* validate with the DTD */
    if (reader != NULL) {
        ret = xmlTextReaderRead(reader);
        while (ret == 1) {
            processNode(reader);
            ret = xmlTextReaderRead(reader);
        }
	/*
	 * Once the document has been fully parsed check the validation results
	 */
	if (xmlTextReaderIsValid(reader) != 1) {
	    fprintf(stderr, "Document %s does not validate\n", filename);
	}
        xmlFreeTextReader(reader);
        if (ret != 0) {
            fprintf(stderr, "%s : failed to parse\n", filename);
        }
    } else {
        fprintf(stderr, "Unable to open %s\n", filename);
    }
}

int main(int argc, char **argv) {
    if (argc != 2)
        return(1);

    /*
     * this initialize the library and check potential ABI mismatches
     * between the version it was compiled for and the actual shared
     * library used.
     */
    LIBXML_TEST_VERSION

    streamFile(argv[1]);

    /*
     * Cleanup function for the XML library.
     */
    xmlCleanupParser();
    /*
     * this is to debug memory for regression tests
     */
    xmlMemoryDump();
    return(0);
}

#else
int main(void) {
    fprintf(stderr, "XInclude support not compiled in\n");
    exit(1);
}
#endif

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<?xml version="1.0" encoding="utf-8"?>
<Address xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
         xsi:noNamespaceSchemaLocation="SimpleAddress.xsd">
  <Recipient>Mr. Walter C. Brown</Recipient>
  <House>49</House>
  <Street>Featherstone Street</Street>
  <Town>LONDON</Town>
  <PostCode>EC1Y 8SY</PostCode>
  <Country>UK</Country>
</Address>

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<?xml version="1.0" encoding="utf-8"?>
<xs:schema elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="Address">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="Recipient" type="xs:string" />
        <xs:element name="House" type="xs:string" />
        <xs:element name="Street" type="xs:string" />
        <xs:element name="Town" type="xs:string" />
        <xs:element name="County" type="xs:string" minOccurs="0" />
        <xs:element name="PostCode" type="xs:string" />
        <xs:element name="Country">
          <xs:simpleType>
            <xs:restriction base="xs:string">
              <xs:enumeration value="IN" />
              <xs:enumeration value="DE" />
              <xs:enumeration value="ES" />
              <xs:enumeration value="UK" />
              <xs:enumeration value="US" />
            </xs:restriction>
          </xs:simpleType>
        </xs:element>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

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