vectorscan/src/nfa/mcclellancompile.h

124 lines
4.5 KiB
C++

/*
* Copyright (c) 2015-2016, 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.
*/
#ifndef MCCLELLANCOMPILE_H
#define MCCLELLANCOMPILE_H
#include "rdfa.h"
#include "ue2common.h"
#include "util/alloc.h"
#include "util/charreach.h"
#include "util/ue2_containers.h"
#include <memory>
#include <vector>
#include <set>
struct NFA;
namespace ue2 {
struct CompileContext;
struct raw_report_info {
raw_report_info();
virtual ~raw_report_info();
virtual u32 getReportListSize() const = 0; /* in bytes */
virtual size_t size() const = 0; /* number of lists */
virtual void fillReportLists(NFA *n, size_t base_offset,
std::vector<u32> &ro /* out */) const = 0;
};
struct escape_info {
CharReach outs;
CharReach outs2_single;
flat_set<std::pair<u8, u8>> outs2;
bool outs2_broken = false;
u32 offset = 0;
u32 outs2_offset = 0;
};
class dfa_build_strat {
public:
virtual ~dfa_build_strat();
virtual raw_dfa &get_raw() const = 0;
virtual std::unique_ptr<raw_report_info> gatherReports(
std::vector<u32> &reports /* out */,
std::vector<u32> &reports_eod /* out */,
u8 *isSingleReport /* out */,
ReportID *arbReport /* out */) const = 0;
virtual escape_info find_escape_strings(dstate_id_t this_idx) const = 0;
virtual size_t accelSize(void) const = 0;
virtual void buildAccel(dstate_id_t this_idx, const escape_info &info,
void *accel_out) = 0;
};
class mcclellan_build_strat : public dfa_build_strat {
public:
explicit mcclellan_build_strat(raw_dfa &r) : rdfa(r) {}
raw_dfa &get_raw() const override { return rdfa; }
std::unique_ptr<raw_report_info> gatherReports(
std::vector<u32> &reports /* out */,
std::vector<u32> &reports_eod /* out */,
u8 *isSingleReport /* out */,
ReportID *arbReport /* out */) const override;
escape_info find_escape_strings(dstate_id_t this_idx) const override;
size_t accelSize(void) const override;
void buildAccel(dstate_id_t this_idx,const escape_info &info,
void *accel_out) override;
virtual u32 max_allowed_offset_accel() const;
private:
raw_dfa &rdfa;
};
/* accel_states: (optional) on success, is filled with the set of accelerable
* states */
ue2::aligned_unique_ptr<NFA>
mcclellanCompile(raw_dfa &raw, const CompileContext &cc,
std::set<dstate_id_t> *accel_states = nullptr);
/* used internally by mcclellan/haig/gough compile process */
ue2::aligned_unique_ptr<NFA>
mcclellanCompile_i(raw_dfa &raw, dfa_build_strat &strat,
const CompileContext &cc,
std::set<dstate_id_t> *accel_states = nullptr);
/**
* \brief Returns the width of the character reach at start.
*/
u32 mcclellanStartReachSize(const raw_dfa *raw);
std::set<ReportID> all_reports(const raw_dfa &rdfa);
bool has_accel_dfa(const NFA *nfa);
} // namespace ue2
#endif