/* * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include <stdint.h>#include <string.h> #include "libavutil/error.h"#include "libavutil/lfg.h"#include "libavutil/log.h" #include "libavcodec/rangecoder.h" #define SIZE 1240 /** * Check if at the current position there is a valid looking termination * @param version version 0 requires the decoder to know the data size in bytes *                version 1 needs about 1 bit more space but does not need to *                          carry the size from encoder to decoder * @returns negative AVERROR code on error or non negative. */static int rac_check_termination(RangeCoder *c, int version){    if (version == 1) {        RangeCoder tmp = *c;        get_rac(c, (uint8_t[]) { 129 });         if (c->bytestream == tmp.bytestream && c->bytestream > c->bytestream_start)            tmp.low -= *--tmp.bytestream;        tmp.bytestream_end = tmp.bytestream;         if (get_rac(&tmp, (uint8_t[]) { 129 }))            return AVERROR_INVALIDDATA;    } else {        if (c->bytestream_end != c->bytestream)            return AVERROR_INVALIDDATA;    }    return 0;} int main(void){    RangeCoder c;    uint8_t b[9 * SIZE] = {0};    uint8_t r[9 * SIZE];    int i, p, actual_length, version;    uint8_t state[10];    AVLFG prng;     av_lfg_init(&prng, 1);    for (version = 0; version < 2; version++) {        for (p = 0; p< 1024; p++) {            ff_init_range_encoder(&c, b, SIZE);            ff_build_rac_states(&c, (1LL << 32) / 20, 128 + 64 + 32 + 16);             memset(state, 128, sizeof(state));             for (i = 0; i < SIZE; i++)                r[i] = av_lfg_get(&prng) % 7;             for (i = 0; i < SIZE; i++)                put_rac(&c, state, r[i] & 1);             actual_length = ff_rac_terminate(&c, version);             ff_init_range_decoder(&c, b, version ? SIZE : actual_length);             memset(state, 128, sizeof(state));             for (i = 0; i < SIZE; i++)                if ((r[i] & 1) != get_rac(&c, state)) {                    av_log(NULL, AV_LOG_ERROR, "rac failure at %d pass %d version %d\n", i, p, version);                    return 1;                }             if (rac_check_termination(&c, version) < 0) {                av_log(NULL, AV_LOG_ERROR, "rac failure at termination pass %d version %d\n", p, version);                return 1;            }            if (c.bytestream - c.bytestream_start - actual_length != version) {                av_log(NULL, AV_LOG_ERROR, "rac failure at pass %d version %d\n", p, version);                return 1;            }        }    }     return 0;}