Initial commit of Hyperscan

2026-01-01 22:25:42 +03:00 · 2015-10-20 09:13:35 +11:00
commit 904e436f11
610 changed files with 213627 additions and 0 deletions
--- a/src/parser/ComponentRepeat.h
+++ b/src/parser/ComponentRepeat.h
@@ -0,0 +1,146 @@
+/*
+ * 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 Repeats ('*', '+', '?', '{M,N}', etc)
+ */
+
+#ifndef RE_COMPONENTREPEAT_H
+#define RE_COMPONENTREPEAT_H
+
+#include "Component.h"
+#include "position.h"
+#include "ue2common.h"
+
+#include <memory>
+#include <utility>
+
+namespace ue2 {
+
+/** \brief Encapsulates a repeat of a subexpression ('*', '+', '?', '{M,N}',
+ * etc).
+ *
+ * Ascii Art Time:
+ *
+ * Our standard representation of standard repeats. Other constructions (fan-in
+ * vs fan-out) would also be possible and equivalent for our purposes.
+ *
+ * {n,m}
+ *
+ * S->M->M->M->O->O->O->T
+ *          |     ^  ^  ^
+ *          |     |  |  |
+ *          \-----------/
+ *
+ * {0,m}
+ *
+ * S->O->O->O->T
+ * |     ^  ^  ^
+ * |     |  |  |
+ * \-----------/
+ *
+ */
+
+class ComponentRepeat : public Component {
+    friend class ConstructLiteralVisitor;
+    friend class DumpVisitor;
+    friend class PrintVisitor;
+    friend class SimplifyVisitor;
+public:
+    /** \brief Value representing no maximum bound. */
+    static constexpr u32 NoLimit = 0xffffffff;
+
+    /** \brief Type of this repeat, characterising its
+     * greediness/possessiveness. */
+    enum RepeatType {
+        /** Minimising repeat, like 'a*?'. */
+        REPEAT_NONGREEDY,
+        /** Maximising repeat, like 'a*'. This is the default in PCRE. */
+        REPEAT_GREEDY,
+        /** Possessive, maximising repeat, like 'a*+'. Possessive repeats are
+         * only currently supported in prefiltering mode, where we treat them
+         * the same way we treat normal greedy repeats. */
+        REPEAT_POSSESSIVE,
+    };
+
+    ComponentRepeat(std::unique_ptr<Component> sub_comp, u32 min, u32 max,
+                    RepeatType t);
+    ~ComponentRepeat() override;
+    ComponentRepeat *clone() const override;
+    Component *accept(ComponentVisitor &v) override;
+    void accept(ConstComponentVisitor &v) const override;
+
+    std::vector<PositionInfo> first() const override;
+    std::vector<PositionInfo> last() const override;
+    bool empty() const override;
+    bool repeatable() const override;
+    bool vacuous_everywhere() 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;
+
+    void optimise(bool connected_to_sds) override;
+
+    virtual std::pair<u32, u32> getBounds() const {
+        return std::make_pair(m_min, m_max);
+    }
+
+    /** \brief From declared behaviour (not taking into account the
+     * sub-component).  */
+    enum RepeatType type;
+
+protected:
+    /** Called by \ref buildFollowSet to connect up the various repeats. */
+    void precalc_firsts();
+    void postSubNotePositionHook();
+    void wireRepeats(GlushkovBuildState &bs,
+                     const std::vector<PositionInfo> &lastPos);
+
+    std::unique_ptr<Component> sub_comp;
+    u32 m_min;
+    u32 m_max;
+
+    std::vector<std::vector<PositionInfo> > m_firsts;
+    std::vector<std::vector<PositionInfo> > m_lasts;
+    Position posFirst;
+    Position posLast;
+
+    std::vector<PositionInfo> firsts_cache;
+
+    ComponentRepeat(const ComponentRepeat &other);
+};
+
+std::unique_ptr<ComponentRepeat>
+makeComponentRepeat(std::unique_ptr<Component> sub_comp, u32 min, u32 max,
+                    ComponentRepeat::RepeatType t);
+
+} // namespace ue2
+
+#endif // _RE_COMPONENTREPEAT_H_