diff ext/sord/src/sord_validate.c @ 226:c5cdc9e6a4bf

Add these external library files

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ext/sord/src/sord_validate.c	Fri Jun 09 16:41:31 2017 +0100
@@ -0,0 +1,788 @@
+/*
+  Copyright 2012-2017 David Robillard <http://drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#define _BSD_SOURCE     1 // for realpath
+#define _DEFAULT_SOURCE 1 // for realpath
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef _WIN32
+#    include <windows.h>
+#endif
+
+#include "serd/serd.h"
+#include "sord/sord.h"
+#include "sord_config.h"
+
+#ifdef HAVE_PCRE
+#    include <pcre.h>
+#endif
+
+#define USTR(s) ((const uint8_t*)s)
+
+#define NS_foaf (const uint8_t*)"http://xmlns.com/foaf/0.1/"
+#define NS_owl  (const uint8_t*)"http://www.w3.org/2002/07/owl#"
+#define NS_rdf  (const uint8_t*)"http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+#define NS_rdfs (const uint8_t*)"http://www.w3.org/2000/01/rdf-schema#"
+#define NS_xsd  (const uint8_t*)"http://www.w3.org/2001/XMLSchema#"
+
+typedef struct {
+	SordNode* foaf_Document;
+	SordNode* owl_AnnotationProperty;
+	SordNode* owl_Class;
+	SordNode* owl_DatatypeProperty;
+	SordNode* owl_FunctionalProperty;
+	SordNode* owl_InverseFunctionalProperty;
+	SordNode* owl_ObjectProperty;
+	SordNode* owl_OntologyProperty;
+	SordNode* owl_Restriction;
+	SordNode* owl_Thing;
+	SordNode* owl_cardinality;
+	SordNode* owl_equivalentClass;
+	SordNode* owl_maxCardinality;
+	SordNode* owl_minCardinality;
+	SordNode* owl_onDatatype;
+	SordNode* owl_onProperty;
+	SordNode* owl_someValuesFrom;
+	SordNode* owl_withRestrictions;
+	SordNode* rdf_PlainLiteral;
+	SordNode* rdf_Property;
+	SordNode* rdf_first;
+	SordNode* rdf_rest;
+	SordNode* rdf_type;
+	SordNode* rdfs_Class;
+	SordNode* rdfs_Literal;
+	SordNode* rdfs_Resource;
+	SordNode* rdfs_domain;
+	SordNode* rdfs_label;
+	SordNode* rdfs_range;
+	SordNode* rdfs_subClassOf;
+	SordNode* xsd_anyURI;
+	SordNode* xsd_decimal;
+	SordNode* xsd_double;
+	SordNode* xsd_maxInclusive;
+	SordNode* xsd_minInclusive;
+	SordNode* xsd_pattern;
+	SordNode* xsd_string;
+} URIs;
+
+int  n_errors        = 0;
+int  n_restrictions  = 0;
+bool one_line_errors = false;
+
+static int
+print_version(void)
+{
+	printf("sord_validate " SORD_VERSION
+	       " <http://drobilla.net/software/sord>\n");
+	printf("Copyright 2012-2017 David Robillard <http://drobilla.net>.\n"
+	       "License: <http://www.opensource.org/licenses/isc>\n"
+	       "This is free software; you are free to change and redistribute it."
+	       "\nThere is NO WARRANTY, to the extent permitted by law.\n");
+	return 0;
+}
+
+static int
+print_usage(const char* name, bool error)
+{
+	FILE* const os = error ? stderr : stdout;
+	fprintf(os, "Usage: %s [OPTION]... INPUT...\n", name);
+	fprintf(os, "Validate RDF data\n\n");
+	fprintf(os, "  -h  Display this help and exit\n");
+	fprintf(os, "  -l  Print errors on a single line.\n");
+	fprintf(os, "  -v  Display version information and exit\n");
+	fprintf(os,
+	        "Validate RDF data.  This is a simple validator which checks\n"
+	        "that all used properties are actually defined.  It does not do\n"
+	        "any fancy file retrieval, the files passed on the command line\n"
+	        "are the only data that is read.  In other words, you must pass\n"
+	        "the definition of all vocabularies used on the command line.\n");
+	return error ? 1 : 0;
+}
+
+static uint8_t*
+absolute_path(const uint8_t* path)
+{
+#ifdef _WIN32
+	char* out = (char*)malloc(MAX_PATH);
+	GetFullPathName((const char*)path, MAX_PATH, out, NULL);
+	return (uint8_t*)out;
+#else
+	return (uint8_t*)realpath((const char*)path, NULL);
+#endif
+}
+
+static int
+errorf(const SordQuad quad, const char* fmt, ...)
+{
+	va_list args;
+	va_start(args, fmt);
+	fprintf(stderr, "error: ");
+	vfprintf(stderr, fmt, args);
+	va_end(args);
+
+	const char* sep = one_line_errors ? "\t" : "\n       ";
+	fprintf(stderr, "%s%s%s%s%s%s\n",
+	        sep, (const char*)sord_node_get_string(quad[SORD_SUBJECT]),
+	        sep, (const char*)sord_node_get_string(quad[SORD_PREDICATE]),
+	        sep, (const char*)sord_node_get_string(quad[SORD_OBJECT]));
+
+	++n_errors;
+	return 1;
+}
+
+static bool
+is_descendant_of(SordModel*      model,
+                 const URIs*     uris,
+                 const SordNode* child,
+                 const SordNode* parent,
+                 const SordNode* pred)
+{
+	if (!child) {
+		return false;
+	} else if (sord_node_equals(child, parent) ||
+	           sord_ask(model, child, uris->owl_equivalentClass, parent, NULL)) {
+		return true;
+	}
+
+	SordIter* i = sord_search(model, child, pred, NULL, NULL);
+	for (; !sord_iter_end(i); sord_iter_next(i)) {
+		const SordNode* o = sord_iter_get_node(i, SORD_OBJECT);
+		if (sord_node_equals(child, o)) {
+			continue;  // Weird class is explicitly a descendent of itself
+		}
+		if (is_descendant_of(model, uris, o, parent, pred)) {
+			sord_iter_free(i);
+			return true;
+		}
+	}
+	sord_iter_free(i);
+
+	return false;
+}
+
+static bool
+regexp_match(const uint8_t* pat, const char* str)
+{
+#ifdef HAVE_PCRE
+	// Append a $ to the pattern so we only match if the entire string matches
+	const size_t len  = strlen((const char*)pat);
+	char* const  regx = (char*)malloc(len + 2);
+	memcpy(regx, pat, len);
+	regx[len]     = '$';
+	regx[len + 1] = '\0';
+
+	const char* err;
+	int         erroffset;
+	pcre*       re = pcre_compile(regx, PCRE_ANCHORED, &err, &erroffset, NULL);
+	free(regx);
+	if (!re) {
+		fprintf(stderr, "Error in pattern `%s' at offset %d (%s)\n",
+		        pat, erroffset, err);
+		return false;
+	}
+
+	const bool ret = pcre_exec(re, NULL, str, strlen(str), 0, 0, NULL, 0) >= 0;
+	pcre_free(re);
+	return ret;
+#endif  // HAVE_PCRE
+	return true;
+}
+
+static int
+bound_cmp(SordModel*      model,
+          const URIs*     uris,
+          const SordNode* literal,
+          const SordNode* type,
+          const SordNode* bound)
+{
+	const char* str        = (const char*)sord_node_get_string(literal);
+	const char* bound_str  = (const char*)sord_node_get_string(bound);
+	const bool  is_numeric =
+		is_descendant_of(model, uris, type, uris->xsd_decimal, uris->owl_onDatatype) ||
+		is_descendant_of(model, uris, type, uris->xsd_double, uris->owl_onDatatype);
+
+	if (is_numeric) {
+		const double fbound   = serd_strtod(bound_str, NULL);
+		const double fliteral = serd_strtod(str, NULL);
+		return ((fliteral < fbound) ? -1 :
+		        (fliteral > fbound) ? 1 :
+		        0);
+	} else {
+		return strcmp(str, bound_str);
+	}
+}
+
+static bool
+check_restriction(SordModel*      model,
+                  const URIs*     uris,
+                  const SordNode* literal,
+                  const SordNode* type,
+                  const SordNode* restriction)
+{
+	size_t      len = 0;
+	const char* str = (const char*)sord_node_get_string_counted(literal, &len);
+
+	// Check xsd:pattern
+	SordIter* p = sord_search(model, restriction, uris->xsd_pattern, 0, 0);
+	if (p) {
+		const SordNode* pat  = sord_iter_get_node(p, SORD_OBJECT);
+		if (!regexp_match(sord_node_get_string(pat), str)) {
+			fprintf(stderr, "`%s' does not match <%s> pattern `%s'\n",
+			        sord_node_get_string(literal),
+			        sord_node_get_string(type),
+			        sord_node_get_string(pat));
+			sord_iter_free(p);
+			return false;
+		}
+		sord_iter_free(p);
+		++n_restrictions;
+	}
+
+	// Check xsd:minInclusive
+	SordIter* l = sord_search(model, restriction, uris->xsd_minInclusive, 0, 0);
+	if (l) {
+		const SordNode* lower = sord_iter_get_node(l, SORD_OBJECT);
+		if (bound_cmp(model, uris, literal, type, lower) < 0) {
+			fprintf(stderr, "`%s' is not >= <%s> minimum `%s'\n",
+			        sord_node_get_string(literal),
+			        sord_node_get_string(type),
+			        sord_node_get_string(lower));
+			sord_iter_free(l);
+			return false;
+		}
+		sord_iter_free(l);
+		++n_restrictions;
+	}
+
+	// Check xsd:maxInclusive
+	SordIter* u = sord_search(model, restriction, uris->xsd_maxInclusive, 0, 0);
+	if (u) {
+		const SordNode* upper = sord_iter_get_node(u, SORD_OBJECT);
+		if (bound_cmp(model, uris, literal, type, upper) > 0) {
+			fprintf(stderr, "`%s' is not <= <%s> maximum `%s'\n",
+			        sord_node_get_string(literal),
+			        sord_node_get_string(type),
+			        sord_node_get_string(upper));
+			sord_iter_free(u);
+			return false;
+		}
+		sord_iter_free(u);
+		++n_restrictions;
+	}
+
+	return true;  // Unknown restriction, be quietly tolerant
+}
+
+static bool
+literal_is_valid(SordModel*      model,
+                 const URIs*     uris,
+                 const SordQuad  quad,
+                 const SordNode* literal,
+                 const SordNode* type)
+{
+	if (!type) {
+		return true;
+	}
+
+	/* Check that literal data is related to required type.  We don't do a
+	   strict subtype check here because e.g. an xsd:decimal might be a valid
+	   xsd:unsignedInt, which the pattern checks will verify, but if the
+	   literal type is not related to the required type at all
+	   (e.g. xsd:decimal and xsd:string) there is a problem. */
+	const SordNode* datatype = sord_node_get_datatype(literal);
+	if (datatype && datatype != type) {
+		if (!is_descendant_of(
+			    model, uris,
+			    datatype, type, uris->owl_onDatatype) &&
+		    !is_descendant_of(
+			    model, uris,
+			    type, datatype, uris->owl_onDatatype) &&
+		    !(sord_node_equals(datatype, uris->xsd_decimal) &&
+		      is_descendant_of(
+			      model, uris,
+			      type, uris->xsd_double, uris->owl_onDatatype))) {
+			errorf(quad,
+			       "Literal `%s' datatype <%s> is not compatible with <%s>\n",
+			       sord_node_get_string(literal),
+			       sord_node_get_string(datatype),
+			       sord_node_get_string(type));
+			return false;
+		}
+	}
+
+	// Find restrictions list
+	SordIter* rs = sord_search(model, type, uris->owl_withRestrictions, 0, 0);
+	if (sord_iter_end(rs)) {
+		return true;  // No restrictions
+	}
+
+	// Walk list, checking each restriction
+	const SordNode* head = sord_iter_get_node(rs, SORD_OBJECT);
+	while (head) {
+		SordIter* f = sord_search(model, head, uris->rdf_first, 0, 0);
+		if (!f) {
+			break;  // Reached end of restrictions list without failure
+		}
+
+		// Check this restriction
+		const bool good = check_restriction(
+			model, uris, literal, type, sord_iter_get_node(f, SORD_OBJECT));
+		sord_iter_free(f);
+
+		if (!good) {
+			sord_iter_free(rs);
+			return false;  // Failed, literal is invalid
+		}
+
+		// Seek to next list node
+		SordIter* n = sord_search(model, head, uris->rdf_rest, 0, 0);
+		head = n ? sord_iter_get_node(n, SORD_OBJECT) : NULL;
+		sord_iter_free(n);
+	}
+
+	sord_iter_free(rs);
+
+	SordIter* s = sord_search(model, type, uris->owl_onDatatype, 0, 0);
+	if (s) {
+		const SordNode* super = sord_iter_get_node(s, SORD_OBJECT);
+		const bool      good  = literal_is_valid(
+			model, uris, quad, literal, super);
+		sord_iter_free(s);
+		return good;  // Match iff literal also matches supertype
+	}
+
+	return true;  // Matches top level type
+}
+
+static bool
+check_type(SordModel*      model,
+           const URIs*     uris,
+           const SordQuad  quad,
+           const SordNode* node,
+           const SordNode* type)
+{
+	if (sord_node_equals(type, uris->rdfs_Resource) ||
+	    sord_node_equals(type, uris->owl_Thing)) {
+		return true;
+	}
+
+	if (sord_node_get_type(node) == SORD_LITERAL) {
+		if (sord_node_equals(type, uris->rdfs_Literal)) {
+			return true;
+		} else if (sord_node_equals(type, uris->rdf_PlainLiteral)) {
+			return !sord_node_get_language(node);
+		} else {
+			return literal_is_valid(model, uris, quad, node, type);
+		}
+	} else if (sord_node_get_type(node) == SORD_URI) {
+		if (sord_node_equals(type, uris->foaf_Document)) {
+			return true;  // Questionable...
+		} else if (is_descendant_of(
+			           model, uris,
+			           type, uris->xsd_anyURI, uris->owl_onDatatype)) {
+			/* Type is any URI and this is a URI, so pass.  Restrictions on
+			   anyURI subtypes are not currently checked (very uncommon). */
+			return true;  // Type is anyURI, and this is a URI
+		} else {
+			SordIter* t = sord_search(model, node, uris->rdf_type, NULL, NULL);
+			for (; !sord_iter_end(t); sord_iter_next(t)) {
+				if (is_descendant_of(model, uris,
+				                     sord_iter_get_node(t, SORD_OBJECT),
+				                     type,
+				                     uris->rdfs_subClassOf)) {
+					sord_iter_free(t);
+					return true;
+				}
+			}
+			sord_iter_free(t);
+			return false;
+		}
+	} else {
+		return true;  // Blanks often lack explicit types, ignore
+	}
+
+	return false;
+}
+
+static uint64_t
+count_non_blanks(SordIter* i, SordQuadIndex field)
+{
+	uint64_t n = 0;
+	for (; !sord_iter_end(i); sord_iter_next(i)) {
+		const SordNode* node = sord_iter_get_node(i, field);
+		if (sord_node_get_type(node) != SORD_BLANK) {
+			++n;
+		}
+	}
+	return n;
+}
+
+static int
+check_properties(SordModel* model, URIs* uris)
+{
+	int       st = 0;
+	SordIter* i  = sord_begin(model);
+	for (; !sord_iter_end(i); sord_iter_next(i)) {
+		SordQuad quad;
+		sord_iter_get(i, quad);
+
+		const SordNode* subj = quad[SORD_SUBJECT];
+		const SordNode* pred = quad[SORD_PREDICATE];
+		const SordNode* obj  = quad[SORD_OBJECT];
+
+		bool is_any_property = false;
+		SordIter* t = sord_search(model, pred, uris->rdf_type, NULL, NULL);
+		for (; !sord_iter_end(t); sord_iter_next(t)) {
+			if (is_descendant_of(model, uris,
+			                     sord_iter_get_node(t, SORD_OBJECT),
+			                     uris->rdf_Property,
+			                     uris->rdfs_subClassOf)) {
+				is_any_property = true;
+				break;
+			}
+		}
+		sord_iter_free(t);
+
+		const bool is_ObjectProperty = sord_ask(
+			model, pred, uris->rdf_type, uris->owl_ObjectProperty, 0);
+		const bool is_FunctionalProperty = sord_ask(
+			model, pred, uris->rdf_type, uris->owl_FunctionalProperty, 0);
+		const bool is_InverseFunctionalProperty = sord_ask(
+			model, pred, uris->rdf_type, uris->owl_InverseFunctionalProperty, 0);
+		const bool is_DatatypeProperty = sord_ask(
+			model, pred, uris->rdf_type, uris->owl_DatatypeProperty, 0);
+
+		if (!is_any_property) {
+			st = errorf(quad, "Use of undefined property");
+		}
+
+		if (!sord_ask(model, pred, uris->rdfs_label, NULL, NULL)) {
+			st = errorf(quad, "Property <%s> has no label",
+			            sord_node_get_string(pred));
+		}
+
+		if (is_DatatypeProperty &&
+		    sord_node_get_type(obj) != SORD_LITERAL) {
+			st = errorf(quad, "Datatype property with non-literal value");
+		}
+
+		if (is_ObjectProperty &&
+		    sord_node_get_type(obj) == SORD_LITERAL) {
+			st = errorf(quad, "Object property with literal value");
+		}
+
+		if (is_FunctionalProperty) {
+			SordIter*      o = sord_search(model, subj, pred, NULL, NULL);
+			const uint64_t n = count_non_blanks(o, SORD_OBJECT);
+			if (n > 1) {
+				st = errorf(quad, "Functional property with %u objects", n);
+			}
+			sord_iter_free(o);
+		}
+
+		if (is_InverseFunctionalProperty) {
+			SordIter*      s = sord_search(model, NULL, pred, obj, NULL);
+			const unsigned n = count_non_blanks(s, SORD_SUBJECT);
+			if (n > 1) {
+				st = errorf(
+					quad, "Inverse functional property with %u subjects", n);
+			}
+			sord_iter_free(s);
+		}
+
+		if (sord_node_equals(pred, uris->rdf_type) &&
+		    !sord_ask(model, obj, uris->rdf_type, uris->rdfs_Class, NULL) &&
+		    !sord_ask(model, obj, uris->rdf_type, uris->owl_Class, NULL)) {
+			st = errorf(quad, "Type is not a rdfs:Class or owl:Class");
+		}
+
+		if (sord_node_get_type(obj) == SORD_LITERAL &&
+		    !literal_is_valid(model, uris, quad,
+		                      obj, sord_node_get_datatype(obj))) {
+			st = errorf(quad, "Literal does not match datatype");
+		}
+
+		SordIter* r = sord_search(model, pred, uris->rdfs_range, NULL, NULL);
+		for (; !sord_iter_end(r); sord_iter_next(r)) {
+			const SordNode* range = sord_iter_get_node(r, SORD_OBJECT);
+			if (!check_type(model, uris, quad, obj, range)) {
+				st = errorf(quad, "Object not in range <%s>\n",
+				            sord_node_get_string(range));
+			}
+		}
+		sord_iter_free(r);
+
+		SordIter* d = sord_search(model, pred, uris->rdfs_domain, NULL, NULL);
+		if (d) {
+			const SordNode* domain = sord_iter_get_node(d, SORD_OBJECT);
+			if (!check_type(model, uris, quad, subj, domain)) {
+				st = errorf(quad, "Subject not in domain <%s>",
+				            sord_node_get_string(domain));
+			}
+			sord_iter_free(d);
+		}
+	}
+	sord_iter_free(i);
+
+	return st;
+}
+
+static int
+check_instance(SordModel*      model,
+               const URIs*     uris,
+               const SordNode* restriction,
+               const SordQuad  quad)
+{
+	const SordNode* instance = quad[SORD_SUBJECT];
+	int             st       = 0;
+
+	const SordNode* prop = sord_get(
+		model, restriction, uris->owl_onProperty, NULL, NULL);
+	if (!prop) {
+		return 0;
+	}
+
+	const unsigned values = sord_count(model, instance, prop, NULL, NULL);
+
+	// Check exact cardinality
+	const SordNode* card = sord_get(
+		model, restriction, uris->owl_cardinality, NULL, NULL);
+	if (card) {
+		const unsigned c = atoi((const char*)sord_node_get_string(card));
+		if (values != c) {
+			st = errorf(quad, "Property %s on %s has %u != %u values",
+			            sord_node_get_string(prop),
+			            sord_node_get_string(instance),
+			            values, c);
+		}
+	}
+
+	// Check minimum cardinality
+	const SordNode* minCard = sord_get(
+		model, restriction, uris->owl_minCardinality, NULL, NULL);
+	if (minCard) {
+		const unsigned m = atoi((const char*)sord_node_get_string(minCard));
+		if (values < m) {
+			st = errorf(quad, "Property %s on %s has %u < %u values",
+			            sord_node_get_string(prop),
+			            sord_node_get_string(instance),
+			            values, m);
+		}
+	}
+
+	// Check maximum cardinality
+	const SordNode* maxCard = sord_get(
+		model, restriction, uris->owl_maxCardinality, NULL, NULL);
+	if (maxCard) {
+		const unsigned m = atoi((const char*)sord_node_get_string(maxCard));
+		if (values < m) {
+			st = errorf(quad, "Property %s on %s has %u > %u values",
+			            sord_node_get_string(prop),
+			            sord_node_get_string(instance),
+			            values, m);
+		}
+	}
+
+	// Check someValuesFrom
+	SordIter* sf = sord_search(
+		model, restriction, uris->owl_someValuesFrom, NULL, NULL);
+	if (sf) {
+		const SordNode* type = sord_iter_get_node(sf, SORD_OBJECT);
+
+		SordIter* v     = sord_search(model, instance, prop, NULL, NULL);
+		bool      found = false;
+		for (; !sord_iter_end(v); sord_iter_next(v)) {
+			const SordNode* value = sord_iter_get_node(v, SORD_OBJECT);
+			if (check_type(model, uris, quad, value, type)) {
+				found = true;
+				break;
+			}
+		}
+		if (!found) {
+			st = errorf(quad, "%s has no <%s> values of type <%s>\n",
+			            sord_node_get_string(instance),
+			            sord_node_get_string(prop),
+			            sord_node_get_string(type));
+		}
+		sord_iter_free(v);
+	}
+	sord_iter_free(sf);
+
+	return st;
+}
+
+static int
+check_class_instances(SordModel*      model,
+                      const URIs*     uris,
+                      const SordNode* restriction,
+                      const SordNode* klass)
+{
+	// Check immediate instances of this class
+	SordIter* i = sord_search(model, NULL, uris->rdf_type, klass, NULL);
+	for (; !sord_iter_end(i); sord_iter_next(i)) {
+		SordQuad quad;
+		sord_iter_get(i, quad);
+		check_instance(model, uris, restriction, quad);
+	}
+	sord_iter_free(i);
+
+	// Check instances of all subclasses recursively
+	SordIter* s = sord_search(model, NULL, uris->rdfs_subClassOf, klass, NULL);
+	for (; !sord_iter_end(s); sord_iter_next(s)) {
+		const SordNode* subklass = sord_iter_get_node(s, SORD_SUBJECT);
+		check_class_instances(model, uris, restriction, subklass);
+	}
+	sord_iter_free(s);
+
+	return 0;
+}
+
+static int
+check_instances(SordModel* model, const URIs* uris)
+{
+	int       st = 0;
+	SordIter* r = sord_search(
+		model, NULL, uris->rdf_type, uris->owl_Restriction, NULL);
+	for (; !sord_iter_end(r); sord_iter_next(r)) {
+		const SordNode* restriction = sord_iter_get_node(r, SORD_SUBJECT);
+		const SordNode* prop        = sord_get(
+			model, restriction, uris->owl_onProperty, NULL, NULL);
+		if (!prop) {
+			continue;
+		}
+
+		SordIter* c = sord_search(
+			model, NULL, uris->rdfs_subClassOf, restriction, NULL);
+		for (; !sord_iter_end(c); sord_iter_next(c)) {
+			const SordNode* klass = sord_iter_get_node(c, SORD_SUBJECT);
+			check_class_instances(model, uris, restriction, klass);
+		}
+		sord_iter_free(c);
+	}
+	sord_iter_free(r);
+
+	return st;
+}
+
+int
+main(int argc, char** argv)
+{
+	if (argc < 2) {
+		return print_usage(argv[0], true);
+	}
+
+	int a = 1;
+	for (; a < argc && argv[a][0] == '-'; ++a) {
+		if (argv[a][1] == 'l') {
+			one_line_errors = true;
+		} else if (argv[a][1] == 'v') {
+			return print_version();
+		} else {
+			fprintf(stderr, "%s: Unknown option `%s'\n", argv[0], argv[a]);
+			return print_usage(argv[0], true);
+		}
+	}
+
+	SordWorld*  world  = sord_world_new();
+	SordModel*  model  = sord_new(world, SORD_SPO|SORD_OPS, false);
+	SerdEnv*    env    = serd_env_new(&SERD_NODE_NULL);
+	SerdReader* reader = sord_new_reader(model, env, SERD_TURTLE, NULL);
+
+	for (; a < argc; ++a) {
+		const uint8_t* input   = (const uint8_t*)argv[a];
+		uint8_t*       in_path = absolute_path(serd_uri_to_path(input));
+
+		if (!in_path) {
+			fprintf(stderr, "Skipping file %s\n", input);
+			continue;
+		}
+
+		SerdURI  base_uri;
+		SerdNode base_uri_node = serd_node_new_file_uri(
+			in_path, NULL, &base_uri, true);
+
+		serd_env_set_base_uri(env, &base_uri_node);
+		const SerdStatus st = serd_reader_read_file(reader, in_path);
+		if (st) {
+			fprintf(stderr, "error reading %s: %s\n",
+			        in_path, serd_strerror(st));
+		}
+
+		serd_node_free(&base_uri_node);
+		free(in_path);
+	}
+	serd_reader_free(reader);
+	serd_env_free(env);
+
+#define URI(prefix, suffix) \
+	uris.prefix##_##suffix = sord_new_uri(world, NS_##prefix #suffix)
+
+	URIs uris;
+	URI(foaf, Document);
+	URI(owl, AnnotationProperty);
+	URI(owl, Class);
+	URI(owl, DatatypeProperty);
+	URI(owl, FunctionalProperty);
+	URI(owl, InverseFunctionalProperty);
+	URI(owl, ObjectProperty);
+	URI(owl, OntologyProperty);
+	URI(owl, Restriction);
+	URI(owl, Thing);
+	URI(owl, cardinality);
+	URI(owl, equivalentClass);
+	URI(owl, maxCardinality);
+	URI(owl, minCardinality);
+	URI(owl, onDatatype);
+	URI(owl, onProperty);
+	URI(owl, someValuesFrom);
+	URI(owl, withRestrictions);
+	URI(rdf, PlainLiteral);
+	URI(rdf, Property);
+	URI(rdf, first);
+	URI(rdf, rest);
+	URI(rdf, type);
+	URI(rdfs, Class);
+	URI(rdfs, Literal);
+	URI(rdfs, Resource);
+	URI(rdfs, domain);
+	URI(rdfs, label);
+	URI(rdfs, range);
+	URI(rdfs, subClassOf);
+	URI(xsd, anyURI);
+	URI(xsd, decimal);
+	URI(xsd, double);
+	URI(xsd, maxInclusive);
+	URI(xsd, minInclusive);
+	URI(xsd, pattern);
+	URI(xsd, string);
+
+#ifndef HAVE_PCRE
+	fprintf(stderr, "warning: Built without PCRE, datatypes not checked.\n");
+#endif
+
+	const int prop_st = check_properties(model, &uris);
+	const int inst_st = check_instances(model, &uris);
+
+	printf("Found %d errors among %d files (checked %d restrictions)\n",
+	       n_errors, argc - 1, n_restrictions);
+
+	sord_free(model);
+	sord_world_free(world);
+	return prop_st || inst_st;
+}