I'm writing some functions in C that parses a part of a XML file (using libxml), but instead of extracting the content of the XML node that has a specific name, it outputs a string that's not in UTF-8 or ASCII.

Here's the XML file in question:

<paths>
  <file_list>
    <group>
      <type>config_directory</type>
      <file>
        <name>AppData/scripts/preferences.empire_script.txt</name>
        <sum>5d064a6cfdc35f4714fd31d5d99735d0</sum>
      </file>
      <file>
        <name>preferences</name>
        <sum>a0f283d89d97a00011f292cc8f9c0d24</sum>
      </file>
    </group>
  </file_list>
</paths>

This is the first function I call, which parses the XML file and finds the XML node with name "file_list"

int 
verify()
{
  xmlDoc *doc = NULL;
  xmlNode *root_element, *cur_node;
  doc = xmlReadFile("test.xml", NULL, 0);
  if (doc == NULL)
    {
      return 1;
    }
  
  root_element = xmlDocGetRootElement (doc);

  if (root_element->type != XML_ELEMENT_NODE || !xmlStrEqual(root_element->name, (const xmlChar*) "paths"))
    {
      return 1;
    }

  cur_node = root_element->children;

  while (cur_node != NULL)
    {
      if (cur_node->type == XML_ELEMENT_NODE && xmlStrEqual(cur_node->name, (const xmlChar*) "file_list"))
	  {
	    if (parse_file_list(cur_node, e) != 0) return 1;
	  }
      cur_node = cur_node->next;
    }
  
  file_close(f);
  return 0;
}

Then I do the same thing in this function and find "group"

static int
parse_file_list(xmlNode *cur)
{
  cur = cur->children;
  while (cur != NULL)
    {
      if (cur->type == XML_ELEMENT_NODE && xmlStrEqual(cur->name, (const xmlChar*) "group"))
	  {
	    if (parse_group(cur) != 0) return 1;
	  }
      cur = cur->next;
    }
  return 0;
}

Here, it should parse the contents of the XML node "type", except I just get a segmentation fault when I call xmlNodeGetContent(cur)

static int
parse_group(xmlNode *cur)
{
  cur = cur->children;
  while (cur != NULL)
    {
      if (cur->type == XML_ELEMENT_NODE && xmlStrEqual(cur->name, (const xmlChar*) "type"))
	  {
	    xmlChar *key = xmlNodeGetContent(cur);
	    xmlFree(key);
	    break;
	  }
      cur = cur->next;
    }

  return 0;
}

Am I missing something?

posted over 3 years ago

CC BY-SA 4.0

3y ago by Alexei‭

southernisles‭

14 reputation 1 0 2 2