1 /*
2  * Copyright (c) 2015, Intel Corporation
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
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8  *    this list of conditions and the following disclaimer.
9  *  * Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *  * Neither the name of Intel Corporation nor the names of its contributors
13  *    may be used to endorse or promote products derived from this software
14  *    without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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27  */
28 
29 /** \file
30  * \brief Bounded repeat compile-time code.
31  */
32 
33 #ifndef REPEATCOMPILE_H
34 #define REPEATCOMPILE_H
35 
36 #include "repeat_internal.h"
37 
38 #include <cstdint>
39 #include <utility>
40 #include <vector>
41 
42 namespace ue2 {
43 
44 class CharReach;
45 class depth;
46 
47 /**
48  * \brief Structure representing the various state requirements for a given
49  * bounded repeat.
50  */
51 struct RepeatStateInfo {
52     RepeatStateInfo(enum RepeatType type, const depth &repeatMin,
53                     const depth &repeatMax, u32 minPeriod);
54 
55     u32 stateSize;
56     u32 packedCtrlSize;
57     u32 horizon;
58     u32 patchCount;
59     u32 patchSize;
60     u32 encodingSize;
61     u32 patchesOffset;
62     std::vector<u32> packedFieldSizes;
63     std::vector<uint64_t> table; // not u64a, for boost/gcc-4.9
64 };
65 
66 /**
67  * \brief Given the parameters of a repeat, choose a repeat implementation
68  * type.
69  */
70 enum RepeatType chooseRepeatType(const depth &repeatMin, const depth &repeatMax,
71                                  u32 minPeriod, bool is_reset,
72                                  bool has_external_guard = false);
73 
74 u32 calcPackedBytes(u64a val);
75 
76 bool matches(std::vector<CharReach>::const_iterator a_it,
77              std::vector<CharReach>::const_iterator a_ite,
78              std::vector<CharReach>::const_iterator b_it,
79              std::vector<CharReach>::const_iterator b_ite);
80 
81 std::vector<size_t>
82 minResetDistToEnd(const std::vector<std::vector<CharReach>> &triggers,
83                   const CharReach &cr);
84 
85 u32 minPeriod(const std::vector<std::vector<CharReach>> &triggers,
86               const CharReach &cr, bool *can_reset);
87 
88 } // namespace ue2
89 
90 #endif // REPEATCOMPILE_H
91