release/src/router/libxml2/doc/examples/reader4.c

   1 /**
   2  * section: xmlReader
   3  * synopsis: Parse multiple XML files reusing an xmlReader
   4  * purpose: Demonstrate the use of xmlReaderForFile() and
   5  * xmlReaderNewFile to parse XML files while reusing the reader object
   6  * and parser context.  (Note that the XMLReader functions require
   7  * libxml2 version later than 2.6.)
   8  * usage: reader4 <filename> [ filename ... ]
   9  * test: reader4 test1.xml test2.xml test3.xml > reader4.tmp && diff reader4.tmp $(srcdir)/reader4.res
  10  * author: Graham Bennett
  11  * copy: see Copyright for the status of this software.
  12  */
  13
  14 #include <stdio.h>
  15 #include <libxml/xmlreader.h>
  16
  17 #ifdef LIBXML_READER_ENABLED
  18
  19 static void processDoc(xmlTextReaderPtr readerPtr) {
  20     int ret;
  21     xmlDocPtr docPtr;
  22     const xmlChar *URL;
  23
  24     ret = xmlTextReaderRead(readerPtr);
  25     while (ret == 1) {
  26       ret = xmlTextReaderRead(readerPtr);
  27     }
  28
  29     /*
  30      * One can obtain the document pointer to get insteresting
  31      * information about the document like the URL, but one must also
  32      * be sure to clean it up at the end (see below).
  33      */
  34     docPtr = xmlTextReaderCurrentDoc(readerPtr);
  35     if (NULL == docPtr) {
  36       fprintf(stderr, "failed to obtain document\n");
  37       return;
  38     }
  39
  40     URL = docPtr->URL;
  41     if (NULL == URL) {
  42       fprintf(stderr, "Failed to obtain URL\n");
  43     }
  44
  45     if (ret != 0) {
  46       fprintf(stderr, "%s: Failed to parse\n", URL);
  47       return;
  48     }
  49
  50     printf("%s: Processed ok\n", (const char *)URL);
  51 }
  52
  53 int main(int argc, char **argv) {
  54     xmlTextReaderPtr readerPtr;
  55     int i;
  56     xmlDocPtr docPtr;
  57
  58     if (argc < 2)
  59         return(1);
  60
  61     /*
  62      * this initialises the library and check potential ABI mismatches
  63      * between the version it was compiled for and the actual shared
  64      * library used.
  65      */
  66     LIBXML_TEST_VERSION
  67
  68     /*
  69      * Create a new reader for the first file and process the
  70      * document.
  71      */
  72     readerPtr = xmlReaderForFile(argv[1], NULL, 0);
  73     if (NULL == readerPtr) {
  74       fprintf(stderr, "%s: failed to create reader\n", argv[1]);
  75       return(1);
  76     }
  77     processDoc(readerPtr);
  78
  79     /*
  80      * The reader can be reused for subsequent files.
  81      */
  82     for (i=2; i < argc; ++i) {
  83         xmlReaderNewFile(readerPtr, argv[i], NULL, 0);
  84         if (NULL == readerPtr) {
  85           fprintf(stderr, "%s: failed to create reader\n", argv[i]);
  86           return(1);
  87         }
  88         processDoc(readerPtr);
  89     }
  90
  91     /*
  92      * Since we've called xmlTextReaderCurrentDoc, we now have to
  93      * clean up after ourselves.  We only have to do this the last
  94      * time, because xmlReaderNewFile calls xmlCtxtReset which takes
  95      * care of it.
  96      */
  97     docPtr = xmlTextReaderCurrentDoc(readerPtr);
  98     if (docPtr != NULL)
  99       xmlFreeDoc(docPtr);
 100
 101     /*
 102      * Clean up the reader.
 103      */
 104     xmlFreeTextReader(readerPtr);
 105
 106     /*
 107      * Cleanup function for the XML library.
 108      */
 109     xmlCleanupParser();
 110     /*
 111      * this is to debug memory for regression tests
 112      */
 113     xmlMemoryDump();
 114     return(0);
 115 }
 116
 117 #else
 118 int main(void) {
 119     fprintf(stderr, "xmlReader support not compiled in\n");
 120     exit(1);
 121 }
 122 #endif