Implemented XML parsing for project preferences

* Parsing uses XPath searches on DOM tree (only done once during initialization)
* Also: improved initialization
* Also: fixed/improved XML adapter (revert b1f8ac4391c33079f12164d3c1057dc95343e341)

src/framework/BOINCClientAdapter.cpp

@@ -19,6 +19,9 @@
  ***************************************************************************/
 
 #include "BOINCClientAdapter.h"
+#include "Libxml2Adapter.h"
+
+#include <sstream>
 
 BOINCClientAdapter::BOINCClientAdapter(string sharedMemoryIdentifier)
 {
@@ -26,6 +29,8 @@ BOINCClientAdapter::BOINCClientAdapter(string sharedMemoryIdentifier)
 	m_SharedMemoryAreaIdentifier = sharedMemoryIdentifier;
 	m_SharedMemoryAreaAvailable = false;
 
+	m_xmlIFace = new Libxml2Adapter();
+
 	m_GraphicsFrameRate = 20;
 	m_GraphicsQualitySetting = BOINCClientAdapter::LowGraphicsQualitySetting;
 	m_GraphicsWindowWidth = 800;
@@ -34,16 +39,19 @@ BOINCClientAdapter::BOINCClientAdapter(string sharedMemoryIdentifier)
 
 BOINCClientAdapter::~BOINCClientAdapter()
 {
+	if(m_xmlIFace) delete m_xmlIFace;
 }
 
 void BOINCClientAdapter::initialize()
 {
+	if(!m_Initialized) {
 		readUserInfo();
 		readSharedMemoryArea();
 		readProjectPreferences();
 
 		m_Initialized = true;
 	}
+}
 
 void BOINCClientAdapter::refresh()
 {
@@ -54,7 +62,7 @@ void BOINCClientAdapter::refresh()
 		/// \todo Check that we're still watching our own WU (or science app)!
 	}
 	else {
-		cerr << "The BOINC Client Adapter has not yet been initialized! Doing so now...";
+		cerr << "The BOINC Client Adapter has not yet been initialized! Doing so now..." << endl;
 		initialize();
 	}
 }
@@ -91,7 +99,52 @@ void BOINCClientAdapter::readSharedMemoryArea()
 
 void BOINCClientAdapter::readProjectPreferences()
 {
+	string temp;
+	istringstream convertor;
+	convertor.exceptions(ios_base::badbit | ios_base::failbit);
 
+	// prepare xml document
+	m_xmlIFace->setXmlDocument(projectInformation(), "http://einstein.phys.uwm.edu");
+
+	// use XPath queries to get attributes
+	try {
+		temp = m_xmlIFace->getSingleNodeContentByXPath("/project_preferences/graphics/@fps");
+		if(temp.length() > 0) {
+			convertor.str(temp);
+			convertor >> dec >> m_GraphicsFrameRate;
+			convertor.clear();
+		}
+
+		temp = m_xmlIFace->getSingleNodeContentByXPath("/project_preferences/graphics/@quality");
+		if(temp.length() > 0) {
+			if(temp == "high") {
+				m_GraphicsQualitySetting = BOINCClientAdapter::HighGraphicsQualitySetting;
+			}
+			else if(temp == "medium") {
+				m_GraphicsQualitySetting = BOINCClientAdapter::MediumGraphicsQualitySetting;
+			}
+			else {
+				m_GraphicsQualitySetting = BOINCClientAdapter::LowGraphicsQualitySetting;
+			}
+		}
+
+		temp = m_xmlIFace->getSingleNodeContentByXPath("/project_preferences/graphics/@width");
+		if(temp.length() > 0) {
+			convertor.str(temp);
+			convertor >> dec >> m_GraphicsWindowWidth;
+			convertor.clear();
+		}
+
+		temp = m_xmlIFace->getSingleNodeContentByXPath("/project_preferences/graphics/@height");
+		if(temp.length() > 0) {
+			convertor.str(temp);
+			convertor >> dec >> m_GraphicsWindowHeight;
+			convertor.clear();
+		}
+	}
+	catch(ios_base::failure) {
+		cerr << "Error parsing project preferences! Using defaults..." << endl;
+	}
 }
 
 string BOINCClientAdapter::applicationInformation() const
@@ -101,8 +154,12 @@ string BOINCClientAdapter::applicationInformation() const
 
 string BOINCClientAdapter::projectInformation() const
 {
-	// TODO: check if we have to add the <project_specific> tag!
-	return m_UserData.project_preferences;
+	// ugly workaround for incomplete XML fragment returned by BOINC!
+	string temp = "<project_preferences>\n";
+	temp += m_UserData.project_preferences;
+	temp += "</project_preferences>\n";
+
+	return temp;
 }
 
 int BOINCClientAdapter::graphicsFrameRate() const

src/framework/BOINCClientAdapter.h

@@ -28,6 +28,8 @@
 #include "boinc_api.h"
 #include "graphics2.h"
 
+#include "XMLProcessorInterface.h"
+
 using namespace std;
 
 /**
@@ -226,7 +228,7 @@ public:
 	 * (not yet literally a XML schema, will be provided later) with respect to graphics settings:
      *
      \verbatim
-     <project_specific>
+     <project_preferences>
      	<graphics fps="20" quality="low" width="800" height="600">
      		<starsphere>
      			<feature id="globe" enabled="true" />
@@ -235,7 +237,7 @@ public:
      			<feature id="sound" enabled="false" />
      		</waverider>
      	</graphics>
-     </project_specific>
+     </project_preferences>
      \endverbatim
      *
      * The \c graphics tag and its four attributes \b must be provided as shown above where
@@ -380,6 +382,9 @@ private:
 	 * user account, work unit and computation session.
 	 */
 	APP_INIT_DATA m_UserData;
+
+	/// Pointer to the XML processor
+	XMLProcessorInterface* m_xmlIFace;
 };
 
 /**

src/framework/Libxml2Adapter.cpp

@@ -32,6 +32,8 @@ Libxml2Adapter::Libxml2Adapter()
 
 Libxml2Adapter::~Libxml2Adapter()
 {
+	if(m_xmlDocument) xmlFreeDoc(m_xmlDocument);
+	xmlCleanupParser();
 }
 
 void Libxml2Adapter::setXmlDocument(const string xml, const string url)
@@ -48,7 +50,7 @@ void Libxml2Adapter::setXmlDocument(const string xml, const string url)
 string Libxml2Adapter::getSingleNodeContentByXPath(const string xpath)
 {
 	// no document available!
-	if(!m_xmlDocument) return(NULL);
+	if(!m_xmlDocument) return("");
 
 	// prepare xpath search
 	stringstream buffer;
@@ -64,11 +66,11 @@ string Libxml2Adapter::getSingleNodeContentByXPath(const string xpath)
 
     if(size == 0) {
     	cerr << "No node found using XPath expression: " << xpath << endl;
-    	return(NULL);
+    	return("");
     }
     else if(size < 1) {
     	cerr << "More than node found using XPath expression: " << xpath << endl;
-    	return(NULL);
+    	return("");
     }
 
     // convert xml contents

src/framework/Libxml2Adapter.h

@@ -84,13 +84,13 @@ public:
 	 * This method takes a XPath expression that properly defines how to search
 	 * for a specific node (element or attribute). If the XPath search results
 	 * in more than one instance or if the node (or its content) can't be found
-	 * the return value is NULL.
+	 * the return value is an empty string.
 	 *
 	 * \param xml The XML document to be used for processing
 	 * \param url The base URL of the document
 	 * \param xpath The XPath expression to be used for seaching
 	 *
-	 * \return The node's content or NULL in case of an error
+	 * \return The node's content or an empty string in case of an error
 	 */
 	string getSingleNodeContentByXPath(const string xml, const string url, const string xpath);