Allow to set empty content to node and remove deprecated api usage (#612)

IB-8164

Signed-off-by: Raul Metsma <raul@metsma.ee>

Author: metsma

src/Container.cpp

@@ -104,10 +104,6 @@ void digidoc::initialize(const string &appInfo, const string &userAgent, initCal
     m_userAgent = userAgent;
 
     LIBXML_TEST_VERSION
-    xmlLineNumbersDefaultValue = 1;
-    xmlLoadExtDtdDefaultValue = XML_DETECT_IDS | XML_COMPLETE_ATTRS;
-    xmlSubstituteEntitiesDefault(1);
-    xmlIndentTreeOutput = 1;
     if(xmlSecInit() < 0)
         THROW("Error during initialisation of xmlsec.");
     if(xmlSecCheckVersion() != 1)

src/XMLDocument.h

@@ -252,11 +252,9 @@ struct XMLNode: public XMLElem<xmlNode>
 
     XMLNode& operator=(sv text) noexcept
     {
-        if(!d || text.empty())
+        if(!d)
             return *this;
-        xmlChar *content = xmlEncodeSpecialChars(d->doc, pcxmlChar(text.data()));
-        xmlNodeSetContent(d, content);
-        xmlFree(content);
+        xmlNodeSetContent(d, pcxmlChar(text.data()));
         return *this;
     }
 
@@ -325,8 +323,10 @@ struct XMLDocument: public unique_xml_t<decltype(xmlFreeDoc)>, public XMLNode
             return is->good() || is->eof() ? int(is->gcount()) : -1;
         }, nullptr, &is, XML_CHAR_ENCODING_NONE), xmlFreeParserCtxt);
         ctxt->linenumbers = 1;
+        ctxt->options |= XML_PARSE_NOENT|XML_PARSE_DTDLOAD|XML_PARSE_DTDATTR|XML_PARSE_NONET;
+        ctxt->loadsubset |= XML_DETECT_IDS|XML_COMPLETE_ATTRS;
         if(hugeFile)
-            ctxt->options = XML_PARSE_HUGE;
+            ctxt->options |= XML_PARSE_HUGE;
         auto result = xmlParseDocument(ctxt.get());
         if(result != 0 || !ctxt->wellFormed)
             THROW("%s", ctxt->lastError.message);