/* * Copyright (c) 2017-present, Facebook, Inc. * All rights reserved. * * This source code is licensed under both the BSD-style license (found in the * LICENSE file in the root directory of this source tree) and the GPLv2 (found * in the COPYING file in the root directory of this source tree). * You may select, at your option, one of the above-listed licenses. */ #ifndef SEQGEN_H #define SEQGEN_H #define XXH_STATIC_LINKING_ONLY #include "xxhash.h" #include <stddef.h> /* size_t */ typedef enum { SEQ_gen_ml = 0, SEQ_gen_ll, SEQ_gen_of, SEQ_gen_max /* Must be the last value */ } SEQ_gen_type; /* Internal state, do not use */ typedef struct { XXH64_state_t xxh; /* xxh state for all the data produced so far (seed=0) */ unsigned seed; int state; /* enum to control state machine (clean=0) */ unsigned saved; size_t bytesLeft; } SEQ_stream; SEQ_stream SEQ_initStream(unsigned seed); typedef struct { void* dst; size_t size; size_t pos; } SEQ_outBuffer; /* Returns non-zero until the current type/value has been generated. * Must pass the same type/value until it returns 0. * * Recommended to pick a value in the middle of the range you want, since there * may be some noise that causes actual results to be slightly different. * We try to be more accurate for smaller values. * * NOTE: Very small values don't work well (< 6). */ size_t SEQ_gen(SEQ_stream* stream, SEQ_gen_type type, unsigned value, SEQ_outBuffer* out); /* Returns the xxhash of the data produced so far */ XXH64_hash_t SEQ_digest(SEQ_stream const* stream); #endif /* SEQGEN_H */ |