Initial commit of Hyperscan

src/parser/unsupported.cpp

@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2015, Intel Corporation
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  * Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *  * Neither the name of Intel Corporation nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** \file
+ * \brief Checks component trees for unsupported components.
+  */
+#include "ConstComponentVisitor.h"
+#include "ComponentEUS.h"
+#include "ComponentRepeat.h"
+#include "ComponentWordBoundary.h"
+#include "parse_error.h"
+#include "unsupported.h"
+
+#include <sstream>
+
+namespace ue2 {
+
+/** \brief Visitor class that throws a ParseError exception when it encounters
+ * an unsupported component. */
+class UnsupportedVisitor : public DefaultConstComponentVisitor {
+public:
+    ~UnsupportedVisitor();
+    void pre(const ComponentAssertion &) override {
+        throw ParseError("Zero-width assertions are not supported.");
+    }
+    void pre(const ComponentAtomicGroup &) override {
+        throw ParseError("Atomic groups are unsupported.");
+    }
+    void pre(const ComponentBackReference &) override {
+        throw ParseError("Back-references are unsupported.");
+    }
+    void pre(const ComponentCondReference &) override {
+        throw ParseError("Conditional references are not supported.");
+    }
+    void pre(const ComponentEUS &c) override {
+        std::ostringstream str;
+        str << "\\X unsupported at index " << c.loc << ".";
+        throw ParseError(str.str());
+    }
+    void pre(const ComponentRepeat &c) override {
+        if (c.type == ComponentRepeat::REPEAT_POSSESSIVE) {
+            throw ParseError("Possessive quantifiers are not supported.");
+        }
+    }
+    void pre(const ComponentWordBoundary &c) override {
+        if (c.ucp && !c.prefilter) {
+            std::ostringstream str;
+            str << (!c.negated ? "\\b" : "\\B")
+                << " unsupported in UCP mode at index " << c.loc << ".";
+            throw ParseError(str.str());
+        }
+    }
+};
+
+UnsupportedVisitor::~UnsupportedVisitor() {}
+
+void checkUnsupported(const Component &root) {
+    UnsupportedVisitor vis;
+    root.accept(vis);
+}
+
+} // namespace ue2