/* * 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 Bounded Repeat implementation for the LimEx NFA. */ #ifndef LIMEX_RING_H #define LIMEX_RING_H #include "ue2common.h" #include "repeat.h" #ifdef __cplusplus extern "C" { #endif /** \brief Return values from \ref processTugTrigger, used to provide feedback * about a bounded repeat to the caller. * * TRIGGER_FAIL does not get cached as we prefer to use TRIGGER_STALE which * allows the exception to squash the cyclic state as well. */ enum TriggerResult { TRIGGER_FAIL, /**< no valid matches, but history still valid */ TRIGGER_SUCCESS, /**< valid match found */ TRIGGER_STALE, /**< no valid matches and history is invalid (stale) */ TRIGGER_SUCCESS_CACHE /**< valid match found; can cache as the repeat has no upper bound. */ }; /** \brief Handle a TUG trigger: given an \p offset, returns whether a repeat * matches or not. */ static really_inline enum TriggerResult processTugTrigger(const struct RepeatInfo *info, const union RepeatControl *ctrl, const char *state, u64a offset) { DEBUG_PRINTF("tug trigger, %s history, repeat={%u,%u}, offset=%llu, " "ctrl=%p, state=%p\n", repeatTypeName(info->type), info->repeatMin, info->repeatMax, offset, ctrl, state); assert(ISALIGNED(ctrl)); enum RepeatMatch rv = repeatHasMatch(info, ctrl, state, offset); switch (rv) { case REPEAT_NOMATCH: return TRIGGER_FAIL; case REPEAT_STALE: return TRIGGER_STALE; case REPEAT_MATCH: if (info->repeatMax == REPEAT_INF) { // {N,} repeats can be cached. return TRIGGER_SUCCESS_CACHE; } else { return TRIGGER_SUCCESS; } } assert(0); // unreachable return TRIGGER_FAIL; } /** \brief Handle a POS trigger: stores a top in the repeat. */ static really_inline void processPosTrigger(const struct RepeatInfo *info, union RepeatControl *ctrl, char *state, u64a offset, char is_alive) { DEBUG_PRINTF("pos trigger, %s history, repeat={%u,%u}, offset=%llu, " "is_alive=%d\n", repeatTypeName(info->type), info->repeatMin, info->repeatMax, offset, is_alive); assert(ISALIGNED(ctrl)); repeatStore(info, ctrl, state, offset, is_alive); } #ifdef __cplusplus } #endif #endif