Chris@439: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@439: 
Chris@439: /*
Chris@439:     Sonic Visualiser
Chris@439:     An audio file viewer and annotation editor.
Chris@439:     Centre for Digital Music, Queen Mary, University of London.
Chris@439:     This file copyright 2008 QMUL.
Chris@439:    
Chris@439:     This program is free software; you can redistribute it and/or
Chris@439:     modify it under the terms of the GNU General Public License as
Chris@439:     published by the Free Software Foundation; either version 2 of the
Chris@439:     License, or (at your option) any later version.  See the file
Chris@439:     COPYING included with this distribution for more information.
Chris@439: */
Chris@439: 
Chris@439: #include "SimpleSPARQLQuery.h"
Chris@439: #include "base/ProgressReporter.h"
Chris@480: #include "base/Profiler.h"
Chris@480: 
Chris@480: #include <QMutex>
Chris@480: #include <QMutexLocker>
Chris@481: #include <QRegExp>
Chris@480: 
Chris@480: #include <set>
Chris@439: 
Chris@440: #ifdef USE_NEW_RASQAL_API
Chris@440: #include <rasqal/rasqal.h>
Chris@440: #else
Chris@439: #include <rasqal.h>
Chris@440: #endif
Chris@439: 
Chris@480: #ifdef HAVE_REDLAND
Chris@480: #include <redland.h>
Chris@480: #endif
Chris@480: 
Chris@461: //#define DEBUG_SIMPLE_SPARQL_QUERY 1
Chris@461: 
Chris@439: #include <iostream>
Chris@439: 
Chris@439: using std::cerr;
Chris@439: using std::endl;
Chris@439: 
Chris@440: #ifdef USE_NEW_RASQAL_API
Chris@440: class WrasqalWorldWrapper // wrong but wromantic, etc
Chris@440: {
Chris@440: public:
Chris@481:     WrasqalWorldWrapper() :
Chris@481:         m_world(0)
Chris@481:     {
Chris@481:         m_world = rasqal_new_world();
Chris@481:         if (!m_world) {
Chris@481:             cerr << "SimpleSPARQLQuery: ERROR: Failed to create RASQAL world!" << endl;
Chris@481:             return;
Chris@481:         }
Chris@481: /*!!! This appears to be new for 0.9.17?
Chris@481:         if (rasqal_world_open(m_world)) {
Chris@481:             cerr << "SimpleSPARQLQuery: ERROR: Failed to open RASQAL world!" << endl;
Chris@481:             return;
Chris@481:         }
Chris@481: */
Chris@481:     }
Chris@481:     ~WrasqalWorldWrapper()
Chris@481:     {
Chris@481:         rasqal_free_world(m_world);
Chris@481:     }
Chris@440: 
Chris@480:     rasqal_world *getWorld() { return m_world; }
Chris@480:     const rasqal_world *getWorld() const { return m_world; }
Chris@440: 
Chris@440: private:
Chris@440:     rasqal_world *m_world;
Chris@440: };
Chris@440: #endif
Chris@440: 
Chris@480: #ifdef HAVE_REDLAND
Chris@480: class WredlandWorldWrapper
Chris@480: {
Chris@480: public:
Chris@480:     WredlandWorldWrapper() :
Chris@480:         m_world(0), m_storage(0), m_model(0)
Chris@480:     {
Chris@480:         m_world = librdf_new_world();
Chris@481:         if (!m_world) {
Chris@481:             cerr << "SimpleSPARQLQuery: ERROR: Failed to create LIBRDF world!" << endl;
Chris@481:             return;
Chris@481:         }
Chris@480:         librdf_world_open(m_world);
Chris@481:         m_storage = librdf_new_storage(m_world, "trees", NULL, NULL);
Chris@480:         if (!m_storage) {
Chris@481:             std::cerr << "SimpleSPARQLQuery: ERROR: Failed to initialise Redland trees datastore, falling back to memory store" << std::endl;
Chris@480:             m_storage = librdf_new_storage(m_world, NULL, NULL, NULL);
Chris@480:             if (!m_storage) {
Chris@480:                 std::cerr << "SimpleSPARQLQuery: ERROR: Failed to initialise Redland memory datastore" << std::endl;
Chris@480:                 return;
Chris@480:             }                
Chris@480:         }
Chris@480:         m_model = librdf_new_model(m_world, m_storage, NULL);
Chris@480:         if (!m_model) {
Chris@480:             std::cerr << "SimpleSPARQLQuery: ERROR: Failed to initialise Redland data model" << std::endl;
Chris@480:             return;
Chris@480:         }
Chris@480:     }
Chris@480: 
Chris@480:     ~WredlandWorldWrapper()
Chris@480:     {
Chris@480:         while (!m_parsedUris.empty()) {
Chris@480:             librdf_free_uri(m_parsedUris.begin()->second);
Chris@480:             m_parsedUris.erase(m_parsedUris.begin());
Chris@480:         }
Chris@480:         if (m_model) librdf_free_model(m_model);
Chris@480:         if (m_storage) librdf_free_storage(m_storage);
Chris@480:         if (m_world) librdf_free_world(m_world);
Chris@480:     }
Chris@480: 
Chris@480:     bool isOK() const { return (m_model != 0); }
Chris@480: 
Chris@480:     librdf_uri *getUri(QString uriString, QString &errorString)
Chris@480:     {
Chris@480:         QMutexLocker locker(&m_mutex);
Chris@480: 
Chris@480:         if (m_parsedUris.find(uriString) != m_parsedUris.end()) {
Chris@480:             return m_parsedUris[uriString];
Chris@480:         }
Chris@480: 
Chris@480:         librdf_uri *uri = librdf_new_uri
Chris@480:             (m_world, (const unsigned char *)uriString.toUtf8().data());
Chris@480:         if (!uri) {
Chris@480:             errorString = "Failed to construct librdf_uri!";
Chris@480:             return 0;
Chris@480:         }
Chris@480: 
Chris@480:         librdf_parser *parser = librdf_new_parser(m_world, "guess", NULL, NULL);
Chris@480:         if (!parser) {
Chris@480:             errorString = "Failed to initialise Redland parser";
Chris@480:             return 0;
Chris@480:         }
Chris@480:         
Chris@480:         std::cerr << "About to parse \"" << uriString.toStdString() << "\"" << std::endl;
Chris@480: 
Chris@480:         Profiler p("SimpleSPARQLQuery: Parse URI into LIBRDF model");
Chris@480: 
Chris@480:         if (librdf_parser_parse_into_model(parser, uri, NULL, m_model)) {
Chris@480: 
Chris@480:             errorString = QString("Failed to parse RDF from URI \"%1\"")
Chris@480:                 .arg(uriString);
Chris@480:             librdf_free_parser(parser);
Chris@480:             librdf_free_uri(uri);
Chris@480:             return 0;
Chris@480: 
Chris@480:         } else {
Chris@480: 
Chris@480:             librdf_free_parser(parser);
Chris@480:             m_parsedUris[uriString] = uri;
Chris@480:             return uri;
Chris@480:         }
Chris@480:     }
Chris@480:         
Chris@480:     librdf_world *getWorld() { return m_world; }
Chris@480:     const librdf_world *getWorld() const { return m_world; }
Chris@480:         
Chris@480:     librdf_model *getModel() { return m_model; }
Chris@480:     const librdf_model *getModel() const { return m_model; }
Chris@480: 
Chris@480: private:
Chris@480:     librdf_world *m_world;
Chris@480:     librdf_storage *m_storage;
Chris@480:     librdf_model *m_model;
Chris@480: 
Chris@480:     QMutex m_mutex;
Chris@480:     std::map<QString, librdf_uri *> m_parsedUris;
Chris@480: };
Chris@480: #endif
Chris@480: 
Chris@439: class SimpleSPARQLQuery::Impl
Chris@439: {
Chris@439: public:
Chris@480:     Impl(QString fromUri, QString query);
Chris@439:     ~Impl();
Chris@439: 
Chris@439:     void setProgressReporter(ProgressReporter *reporter) { m_reporter = reporter; }
Chris@439:     bool wasCancelled() const { return m_cancelled; }
Chris@439: 
Chris@439:     ResultList execute();
Chris@439: 
Chris@439:     bool isOK() const;
Chris@439:     QString getErrorString() const;
Chris@439: 
Chris@481:     static void setBackEnd(SimpleSPARQLQuery::BackEndPreference p) {
Chris@480:         m_preference = p;
Chris@480:     }
Chris@480: 
Chris@439: protected:
Chris@439:     static void errorHandler(void *, raptor_locator *, const char *);
Chris@439: 
Chris@480:     static QMutex m_mutex;
Chris@480: 
Chris@440: #ifdef USE_NEW_RASQAL_API
Chris@480:     static WrasqalWorldWrapper *m_rasqal;
Chris@440: #else
Chris@480:     static bool m_rasqalInitialised;
Chris@440: #endif
Chris@480: 
Chris@480: #ifdef HAVE_REDLAND
Chris@480:     static WredlandWorldWrapper *m_redland;
Chris@480: #endif
Chris@480: 
Chris@481:     static SimpleSPARQLQuery::BackEndPreference m_preference;
Chris@480: 
Chris@480:     ResultList executeDirectParser();
Chris@480:     ResultList executeDatastore();
Chris@480: 
Chris@480:     QString m_fromUri;
Chris@439:     QString m_query;
Chris@439:     QString m_errorString;
Chris@439:     ProgressReporter *m_reporter;
Chris@439:     bool m_cancelled;
Chris@439: };
Chris@439: 
Chris@440: #ifdef USE_NEW_RASQAL_API
Chris@480: WrasqalWorldWrapper *SimpleSPARQLQuery::Impl::m_rasqal = 0;
Chris@440: #else
Chris@480: bool SimpleSPARQLQuery::Impl::m_rasqalInitialised = false;
Chris@440: #endif
Chris@440: 
Chris@480: #ifdef HAVE_REDLAND
Chris@480: WredlandWorldWrapper *SimpleSPARQLQuery::Impl::m_redland = 0;
Chris@480: #endif
Chris@480: 
Chris@480: QMutex SimpleSPARQLQuery::Impl::m_mutex;
Chris@480: 
Chris@481: SimpleSPARQLQuery::BackEndPreference
Chris@481: SimpleSPARQLQuery::Impl::m_preference = SimpleSPARQLQuery::AutoSelectBackEnd;
Chris@480: 
Chris@480: SimpleSPARQLQuery::SimpleSPARQLQuery(QString fromUri, QString query) :
Chris@480:     m_impl(new Impl(fromUri, query))
Chris@480: {
Chris@480: }
Chris@439: 
Chris@439: SimpleSPARQLQuery::~SimpleSPARQLQuery() 
Chris@439: {
Chris@439:     delete m_impl;
Chris@439: }
Chris@439: 
Chris@439: void
Chris@439: SimpleSPARQLQuery::setProgressReporter(ProgressReporter *reporter)
Chris@439: {
Chris@439:     m_impl->setProgressReporter(reporter);
Chris@439: }
Chris@439: 
Chris@439: bool
Chris@439: SimpleSPARQLQuery::wasCancelled() const
Chris@439: {
Chris@439:     return m_impl->wasCancelled();
Chris@439: }
Chris@439: 
Chris@439: SimpleSPARQLQuery::ResultList
Chris@439: SimpleSPARQLQuery::execute()
Chris@439: {
Chris@439:     return m_impl->execute();
Chris@439: }
Chris@439: 
Chris@439: bool
Chris@439: SimpleSPARQLQuery::isOK() const
Chris@439: {
Chris@439:     return m_impl->isOK();
Chris@439: }
Chris@439: 
Chris@439: QString
Chris@439: SimpleSPARQLQuery::getErrorString() const
Chris@439: {
Chris@439:     return m_impl->getErrorString();
Chris@439: }
Chris@439: 
Chris@480: void
Chris@481: SimpleSPARQLQuery::setBackEnd(BackEndPreference p)
Chris@480: {
Chris@481:     SimpleSPARQLQuery::Impl::setBackEnd(p);
Chris@480: }
Chris@480: 
Chris@480: SimpleSPARQLQuery::Impl::Impl(QString fromUri, QString query) :
Chris@480:     m_fromUri(fromUri),
Chris@439:     m_query(query),
Chris@439:     m_reporter(0),
Chris@439:     m_cancelled(false)
Chris@439: {
Chris@461: #ifdef DEBUG_SIMPLE_SPARQL_QUERY
Chris@461:     std::cerr << "SimpleSPARQLQuery::Impl: Query is: \"" << query.toStdString() << "\"" << std::endl;
Chris@461: #endif
Chris@439: }
Chris@439: 
Chris@439: SimpleSPARQLQuery::Impl::~Impl()
Chris@439: {
Chris@439: }
Chris@439: 
Chris@439: bool
Chris@439: SimpleSPARQLQuery::Impl::isOK() const
Chris@439: {
Chris@439:     return (m_errorString == "");
Chris@439: }
Chris@439: 
Chris@439: QString
Chris@439: SimpleSPARQLQuery::Impl::getErrorString() const
Chris@439: {
Chris@439:     return m_errorString;
Chris@439: }
Chris@439: 
Chris@439: void
Chris@439: SimpleSPARQLQuery::Impl::errorHandler(void *data, 
Chris@439:                                       raptor_locator *locator,
Chris@439:                                       const char *message) 
Chris@439: {
Chris@439:     SimpleSPARQLQuery::Impl *impl = (SimpleSPARQLQuery::Impl *)data;
Chris@439:     
Chris@481:     char buffer[256];
Chris@481:     raptor_format_locator(buffer, 255, locator);
Chris@481:     QString loc(buffer);
Chris@481:     if (loc != "") {
Chris@481:         impl->m_errorString = QString("%1 - %2").arg(loc).arg(message);
Chris@481:     } else {
Chris@481:         impl->m_errorString = message;
Chris@481:     }
Chris@439: 
Chris@439:     cerr << "SimpleSPARQLQuery: ERROR: " << impl->m_errorString.toStdString() << endl;
Chris@439: }
Chris@439: 
Chris@439: SimpleSPARQLQuery::ResultList
Chris@439: SimpleSPARQLQuery::Impl::execute()
Chris@439: {
Chris@439:     ResultList list;
Chris@439: 
Chris@481:     BackEndPreference preference;
Chris@480: 
Chris@480:     m_mutex.lock();
Chris@480: 
Chris@481:     if (m_preference == AutoSelectBackEnd) {
Chris@481: #ifdef HAVE_REDLAND
Chris@481: //        cerr << "librdf version: " << librdf_version_major << "." << librdf_version_minor << "." << librdf_version_release << endl;
Chris@481:         if (librdf_version_major > 1 ||
Chris@481:             (librdf_version_major == 1 &&
Chris@481:              (librdf_version_minor > 0 ||
Chris@481:               (librdf_version_minor == 0 &&
Chris@481:                librdf_version_release > 7)))) {
Chris@481:             cerr << "SimpleSPARQLQuery: Auto-selecting LIBRDF back-end for tree-based storage" << endl;
Chris@481:             m_preference = DatastoreBackEnd;
Chris@481:         }
Chris@481: #endif
Chris@481:         if (m_preference == AutoSelectBackEnd) {
Chris@481:             cerr << "SimpleSPARQLQuery: Auto-selecting RASQAL back-end" << endl;
Chris@481:             m_preference = DirectParserBackEnd;
Chris@481:         }
Chris@481:     }
Chris@481: 
Chris@481:     if (m_preference == DatastoreBackEnd) {
Chris@480: #ifdef HAVE_REDLAND
Chris@480:         if (!m_redland) {
Chris@480:             m_redland = new WredlandWorldWrapper();
Chris@480:             if (!m_redland->isOK()) {
Chris@480:                 cerr << "WARNING: SimpleSPARQLQuery::execute: Failed to initialise Redland datastore, falling back to direct parser implementation" << endl;
Chris@480:                 delete m_redland;
Chris@481:                 m_preference = DirectParserBackEnd;
Chris@480:             }
Chris@480:         }
Chris@480: #else
Chris@480:         cerr << "WARNING: SimpleSPARQLQuery::execute: Datastore implementation preference indicated, but no datastore compiled in; using direct parser" << endl;
Chris@481:         m_preference = DirectParserBackEnd;
Chris@480: #endif
Chris@480:     }
Chris@480: 
Chris@481:     if (m_preference == DirectParserBackEnd) {
Chris@440: #ifdef USE_NEW_RASQAL_API
Chris@480:         if (!m_rasqal) m_rasqal = new WrasqalWorldWrapper();
Chris@440: #else
Chris@480:         if (!m_rasqalInitialised) {
Chris@480:             rasqal_init();
Chris@480:             m_rasqalInitialised = true;
Chris@480:         }
Chris@480: #endif
Chris@440:     }
Chris@480: 
Chris@480:     preference = m_preference;
Chris@480:     m_mutex.unlock();
Chris@480: 
Chris@481:     if (preference == SimpleSPARQLQuery::DirectParserBackEnd) {
Chris@480:         return executeDirectParser();
Chris@480:     } else {
Chris@480:         return executeDatastore();
Chris@480:     }
Chris@480: }
Chris@480: 
Chris@480: SimpleSPARQLQuery::ResultList
Chris@480: SimpleSPARQLQuery::Impl::executeDirectParser()
Chris@480: {
Chris@480:     ResultList list;
Chris@480: 
Chris@480:     Profiler profiler("SimpleSPARQLQuery::executeDirectParser");
Chris@480: 
Chris@480: #ifdef USE_NEW_RASQAL_API
Chris@480:     rasqal_query *query = rasqal_new_query(m_rasqal->getWorld(), "sparql", NULL);
Chris@480: #else
Chris@439:     rasqal_query *query = rasqal_new_query("sparql", NULL);
Chris@440: #endif
Chris@439:     if (!query) {
Chris@439:         m_errorString = "Failed to construct query";
Chris@439:         cerr << "SimpleSPARQLQuery: ERROR: " << m_errorString.toStdString() << endl;
Chris@439:         return list;
Chris@439:     }
Chris@439: 
Chris@439:     rasqal_query_set_error_handler(query, this, errorHandler);
Chris@439:     rasqal_query_set_fatal_error_handler(query, this, errorHandler);
Chris@439: 
Chris@480:     {
Chris@480:         Profiler p("SimpleSPARQLQuery: Prepare RASQAL query");
Chris@480: 
Chris@480:         if (rasqal_query_prepare
Chris@480:             (query, (const unsigned char *)m_query.toUtf8().data(), NULL)) {
Chris@480:             cerr << "SimpleSPARQLQuery: Failed to prepare query" << endl;
Chris@480:             rasqal_free_query(query);
Chris@480:             return list;
Chris@480:         }
Chris@439:     }
Chris@439: 
Chris@480:     rasqal_query_results *results;
Chris@480:     
Chris@480:     {
Chris@480:         Profiler p("SimpleSPARQLQuery: Execute RASQAL query");
Chris@480:         results = rasqal_query_execute(query);
Chris@480:     }
Chris@439:     
Chris@439: //    cerr << "Query executed" << endl;
Chris@439: 
Chris@439:     if (!results) {
Chris@439:         cerr << "SimpleSPARQLQuery: RASQAL query failed" << endl;
Chris@439:         rasqal_free_query(query);
Chris@439:         return list;
Chris@439:     }
Chris@439: 
Chris@439:     if (!rasqal_query_results_is_bindings(results)) {
Chris@439:         cerr << "SimpleSPARQLQuery: RASQAL query has wrong result type (not bindings)" << endl;
Chris@439:         rasqal_free_query_results(results);
Chris@439:         rasqal_free_query(query);
Chris@439:         return list;
Chris@439:     }
Chris@439:     
Chris@439:     int resultCount = 0;
Chris@439:     int resultTotal = rasqal_query_results_get_count(results); // probably wrong
Chris@439:     m_cancelled = false;
Chris@439: 
Chris@439:     while (!rasqal_query_results_finished(results)) {
Chris@439: 
Chris@439:         int count = rasqal_query_results_get_bindings_count(results);
Chris@439: 
Chris@439:         KeyValueMap resultmap;
Chris@439: 
Chris@439:         for (int i = 0; i < count; ++i) {
Chris@439: 
Chris@439:             const unsigned char *name =
Chris@439:                 rasqal_query_results_get_binding_name(results, i);
Chris@439: 
Chris@439:             rasqal_literal *literal =
Chris@439:                 rasqal_query_results_get_binding_value(results, i);
Chris@439: 
Chris@439:             QString key = (const char *)name;
Chris@439: 
Chris@439:             if (!literal) {
Chris@439:                 resultmap[key] = Value();
Chris@439:                 continue;
Chris@439:             }
Chris@439: 
Chris@439:             ValueType type = LiteralValue;
Chris@439:             if (literal->type == RASQAL_LITERAL_URI) type = URIValue;
Chris@439:             else if (literal->type == RASQAL_LITERAL_BLANK) type = BlankValue;
Chris@439: 
Chris@439:             QString text = (const char *)rasqal_literal_as_string(literal);
Chris@439: 
Chris@461: #ifdef DEBUG_SIMPLE_SPARQL_QUERY
Chris@449:             std::cerr << i << ". " << key.toStdString() << " -> " << text.toStdString() << " (type " << type << ")" << std::endl;
Chris@461: #endif
Chris@449: 
Chris@439:             resultmap[key] = Value(type, text);
Chris@439:         }
Chris@439: 
Chris@439:         list.push_back(resultmap);
Chris@439: 
Chris@439:         rasqal_query_results_next(results);
Chris@439: 
Chris@439:         resultCount++;
Chris@439: 
Chris@439:         if (m_reporter) {
Chris@439:             if (resultCount >= resultTotal) {
Chris@439:                 if (m_reporter->isDefinite()) m_reporter->setDefinite(false);
Chris@439:                 m_reporter->setProgress(resultCount);
Chris@439:             } else {
Chris@439:                 m_reporter->setProgress((resultCount * 100) / resultTotal);
Chris@439:             }
Chris@439: 
Chris@439:             if (m_reporter->wasCancelled()) {
Chris@439:                 m_cancelled = true;
Chris@439:                 break;
Chris@439:             }
Chris@439:         }
Chris@439:     }
Chris@439: 
Chris@439:     rasqal_free_query_results(results);
Chris@439:     rasqal_free_query(query);
Chris@439: 
Chris@439:     return list;
Chris@439: }
Chris@440: 
Chris@480: SimpleSPARQLQuery::ResultList
Chris@480: SimpleSPARQLQuery::Impl::executeDatastore()
Chris@480: {
Chris@480:     ResultList list;
Chris@480: #ifndef HAVE_REDLAND
Chris@480:     // This should have been caught by execute()
Chris@480:     cerr << "SimpleSPARQLQuery: INTERNAL ERROR: Datastore not compiled in" << endl;
Chris@480:     return list;
Chris@480: #else
Chris@480:     Profiler profiler("SimpleSPARQLQuery::executeDatastore");
Chris@480: 
Chris@480:     librdf_uri *uri = m_redland->getUri(m_fromUri, m_errorString);
Chris@480:     if (!uri) return list;
Chris@480: 
Chris@481: #ifdef DEBUG_SIMPLE_SPARQL_QUERY
Chris@480:     std::cerr << "SimpleSPARQLQuery: Query is: \"" << m_query.toStdString() << "\"" << std::endl;
Chris@481: #endif
Chris@481: /*!!!
Chris@480:     static std::map<QString, int> counter;
Chris@480:     if (counter.find(m_query) == counter.end()) counter[m_query] = 1;
Chris@480:     else ++counter[m_query];
Chris@480:     std::cerr << "Counter for this query: " << counter[m_query] << std::endl;
Chris@481:     std::cerr << "Base URI is: \"" << m_fromUri.toStdString() << "\"" << std::endl;
Chris@481: */
Chris@480: 
Chris@480:     librdf_query *query;
Chris@480: 
Chris@480:     {
Chris@480:         Profiler p("SimpleSPARQLQuery: Prepare LIBRDF query");
Chris@480:         query = librdf_new_query
Chris@480:             (m_redland->getWorld(), "sparql", NULL,
Chris@480:              (const unsigned char *)m_query.toUtf8().data(), uri);
Chris@480:     }
Chris@480:     
Chris@480:     if (!query) {
Chris@480:         m_errorString = "Failed to construct query";
Chris@480:         return list;
Chris@480:     }
Chris@480: 
Chris@480:     librdf_query_results *results;
Chris@480:     {
Chris@480:         Profiler p("SimpleSPARQLQuery: Execute LIBRDF query");
Chris@480:         results = librdf_query_execute(query, m_redland->getModel());
Chris@480:     }
Chris@480: 
Chris@480:     if (!results) {
Chris@480:         cerr << "SimpleSPARQLQuery: LIBRDF query failed" << endl;
Chris@480:         librdf_free_query(query);
Chris@480:         return list;
Chris@480:     }
Chris@480: 
Chris@480:     if (!librdf_query_results_is_bindings(results)) {
Chris@480:         cerr << "SimpleSPARQLQuery: LIBRDF query has wrong result type (not bindings)" << endl;
Chris@480:         librdf_free_query_results(results);
Chris@480:         librdf_free_query(query);
Chris@480:         return list;
Chris@480:     }
Chris@480:     
Chris@480:     int resultCount = 0;
Chris@480:     int resultTotal = librdf_query_results_get_count(results); // probably wrong
Chris@480:     m_cancelled = false;
Chris@480: 
Chris@480:     while (!librdf_query_results_finished(results)) {
Chris@480: 
Chris@480:         int count = librdf_query_results_get_bindings_count(results);
Chris@480: 
Chris@480:         KeyValueMap resultmap;
Chris@480: 
Chris@480:         for (int i = 0; i < count; ++i) {
Chris@480: 
Chris@480:             const char *name =
Chris@480:                 librdf_query_results_get_binding_name(results, i);
Chris@480: 
Chris@480:             librdf_node *node =
Chris@480:                 librdf_query_results_get_binding_value(results, i);
Chris@480: 
Chris@480:             QString key = (const char *)name;
Chris@480: 
Chris@480:             if (!node) {
Chris@480:                 resultmap[key] = Value();
Chris@480:                 continue;
Chris@480:             }
Chris@480: 
Chris@480:             ValueType type = LiteralValue;
Chris@481:             QString text;
Chris@481: 
Chris@481:             if (librdf_node_is_resource(node)) {
Chris@481: 
Chris@481:                 type = URIValue;
Chris@481:                 librdf_uri *uri = librdf_node_get_uri(node);
Chris@481:                 text = (const char *)librdf_uri_as_string(uri);
Chris@481: 
Chris@481:             } else if (librdf_node_is_literal(node)) {
Chris@481: 
Chris@481:                 type = LiteralValue;
Chris@481:                 text = (const char *)librdf_node_get_literal_value(node);
Chris@481: 
Chris@481:             } else if (librdf_node_is_blank(node)) {
Chris@481: 
Chris@481:                 type = BlankValue;
Chris@481: 
Chris@481:             } else {
Chris@481: 
Chris@480:                 cerr << "SimpleSPARQLQuery: LIBRDF query returned unknown node type (not resource, literal, or blank)" << endl;
Chris@480:             }
Chris@480: 
Chris@480: #ifdef DEBUG_SIMPLE_SPARQL_QUERY
Chris@481:             cerr << i << ". " << key.toStdString() << " -> " << text.toStdString() << " (type " << type << ")" << endl;
Chris@480: #endif
Chris@480: 
Chris@480:             resultmap[key] = Value(type, text);
Chris@480: 
Chris@480:             librdf_free_node(node);
Chris@480:         }
Chris@480: 
Chris@480:         list.push_back(resultmap);
Chris@480: 
Chris@480:         librdf_query_results_next(results);
Chris@480: 
Chris@480:         resultCount++;
Chris@480: 
Chris@480:         if (m_reporter) {
Chris@480:             if (resultCount >= resultTotal) {
Chris@480:                 if (m_reporter->isDefinite()) m_reporter->setDefinite(false);
Chris@480:                 m_reporter->setProgress(resultCount);
Chris@480:             } else {
Chris@480:                 m_reporter->setProgress((resultCount * 100) / resultTotal);
Chris@480:             }
Chris@480: 
Chris@480:             if (m_reporter->wasCancelled()) {
Chris@480:                 m_cancelled = true;
Chris@480:                 break;
Chris@480:             }
Chris@480:         }
Chris@480:     }
Chris@480: 
Chris@480:     librdf_free_query_results(results);
Chris@480:     librdf_free_query(query);
Chris@480: 
Chris@481: #ifdef DEBUG_SIMPLE_SPARQL_QUERY
Chris@481:     cerr << "All results retrieved (" << resultCount << " of them)" << endl;
Chris@481: #endif
Chris@480: 
Chris@480:     return list;
Chris@480: #endif
Chris@480: }
Chris@480: 
Chris@440: SimpleSPARQLQuery::Value
Chris@480: SimpleSPARQLQuery::singleResultQuery(QString fromUri,
Chris@480:                                      QString query, QString binding)
Chris@440: {
Chris@480:     SimpleSPARQLQuery q(fromUri, query);
Chris@440:     ResultList results = q.execute();
Chris@440:     if (!q.isOK()) {
Chris@440:         cerr << "SimpleSPARQLQuery::singleResultQuery: ERROR: "
Chris@440:              << q.getErrorString().toStdString() << endl;
Chris@440:         return Value();
Chris@440:     }
Chris@440:     if (results.empty()) {
Chris@440:         return Value();
Chris@440:     }
Chris@440:     for (int i = 0; i < results.size(); ++i) {
Chris@440:         if (results[i].find(binding) != results[i].end() &&
Chris@440:             results[i][binding].type != NoValue) {
Chris@440:             return results[i][binding];
Chris@440:         }
Chris@440:     }
Chris@440:     return Value();
Chris@440: }
Chris@440: 
Chris@440: 
Chris@440: