1 /* 2 * Copyright (c) 2015-2016, 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: 6 * 7 * * Redistributions of source code must retain the above copyright notice, 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 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /** \file 30 * \brief NFA Callback definitions, used at runtime. 31 */ 32 33 #ifndef NFA_CALLBACK_H 34 #define NFA_CALLBACK_H 35 36 #include "ue2common.h" 37 38 /** \brief The type for an NFA callback. 39 * 40 * This is a function that takes as arguments the current start and end offsets 41 * where the match occurs, the id of the match and the context pointer that was 42 * passed into the NFA API function that executed the NFA. 43 * 44 * The start offset is the "start of match" (SOM) offset for the match. It is 45 * only provided by engines that natively support SOM tracking (e.g. Gough). 46 * 47 * The end offset will be the offset after the character that caused the match. 48 * Thus, if we have a buffer containing 'abc', then a pattern that matches an 49 * empty string will have an offset of 0, a pattern that matches 'a' will have 50 * an offset of 1, and a pattern that matches 'abc' will have an offset of 3, 51 * which will be a value that is 'beyond' the size of the buffer. That is, if 52 * we have n characters in the buffer, there are n+1 different potential 53 * offsets for matches. 54 * 55 * This function should return an int - currently the possible return values 56 * are 0, which means 'stop running the engine' or non-zero, which means 57 * 'continue matching'. 58 */ 59 typedef int (*NfaCallback)(u64a start, u64a end, ReportID id, void *context); 60 61 /** 62 * standard \ref NfaCallback return value indicating that engine execution 63 * should continue. (any non-zero value will serve this purpose) 64 */ 65 #define MO_CONTINUE_MATCHING 1 66 67 /** 68 * \ref NfaCallback return value indicating that engine execution should halt. 69 */ 70 #define MO_HALT_MATCHING 0 71 72 #endif // NFA_CALLBACK_H 73