Initial commit of Hyperscan

src/parser/ComponentEmpty.h

@@ -0,0 +1,75 @@
+/*
+ * 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 Represents an empty regex element, like (?m)
+ */
+
+#ifndef PARSER_COMPONENT_EMPTY_H_
+#define PARSER_COMPONENT_EMPTY_H_
+
+#include "Component.h"
+
+namespace ue2 {
+
+class ComponentEmpty : public Component {
+    friend class DumpVisitor;
+public:
+    ComponentEmpty();
+    ~ComponentEmpty() override;
+    ComponentEmpty *clone() const override;
+
+    Component *accept(ComponentVisitor &v) override {
+        Component *c = v.visit(this);
+        v.post(this);
+        return c;
+    }
+
+    void accept(ConstComponentVisitor &v) const override {
+        v.pre(*this);
+        v.during(*this);
+        v.post(*this);
+    }
+
+    std::vector<PositionInfo> first() const override;
+    std::vector<PositionInfo> last() const override;
+    bool empty() const override;
+    bool vacuous_everywhere() const override;
+    bool repeatable() const override;
+    void notePositions(GlushkovBuildState &bs) override;
+    void buildFollowSet(GlushkovBuildState &bs,
+                                const std::vector<PositionInfo> &lastPos) override;
+
+    bool checkEmbeddedStartAnchor(bool at_start) const override;
+    bool checkEmbeddedEndAnchor(bool at_end) const override;
+
+};
+
+} // namespace ue2
+
+#endif // PARSER_COMPONENT_EMPTY_H_