tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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bitstream.c (2110B)

      1 /*
      2 * Common bit i/o utils
      3 * Copyright (c) 2000, 2001 Fabrice Bellard
      4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
      5 * Copyright (c) 2010 Loren Merritt
      6 *
      7 * alternative bitstream reader & writer by Michael Niedermayer <michaelni@gmx.at>
      8 *
      9 * This file is part of FFmpeg.
     10 *
     11 * FFmpeg is free software; you can redistribute it and/or
     12 * modify it under the terms of the GNU Lesser General Public
     13 * License as published by the Free Software Foundation; either
     14 * version 2.1 of the License, or (at your option) any later version.
     15 *
     16 * FFmpeg is distributed in the hope that it will be useful,
     17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
     18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     19 * Lesser General Public License for more details.
     20 *
     21 * You should have received a copy of the GNU Lesser General Public
     22 * License along with FFmpeg; if not, write to the Free Software
     23 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
     24 */
     25 
     26 /**
     27 * @file
     28 * bitstream api.
     29 */
     30 
     31 #include <stdint.h>
     32 #include <string.h>
     33 
     34 #include "config.h"
     35 #include "libavutil/avassert.h"
     36 #include "libavutil/intreadwrite.h"
     37 #include "put_bits.h"
     38 
     39 void ff_put_string(PutBitContext *pb, const char *string, int terminate_string)
     40 {
     41    while (*string) {
     42        put_bits(pb, 8, *string);
     43        string++;
     44    }
     45    if (terminate_string)
     46        put_bits(pb, 8, 0);
     47 }
     48 
     49 void ff_copy_bits(PutBitContext *pb, const uint8_t *src, int length)
     50 {
     51    int words = length >> 4;
     52    int bits  = length & 15;
     53    int i;
     54 
     55    if (length == 0)
     56        return;
     57 
     58    av_assert0(length <= put_bits_left(pb));
     59 
     60    if (CONFIG_SMALL || words < 16 || put_bits_count(pb) & 7) {
     61        for (i = 0; i < words; i++)
     62            put_bits(pb, 16, AV_RB16(src + 2 * i));
     63    } else {
     64        for (i = 0; put_bits_count(pb) & 31; i++)
     65            put_bits(pb, 8, src[i]);
     66        flush_put_bits(pb);
     67        memcpy(put_bits_ptr(pb), src + i, 2 * words - i);
     68        skip_put_bytes(pb, 2 * words - i);
     69    }
     70 
     71    put_bits(pb, bits, AV_RB16(src + 2 * words) >> (16 - bits));
     72 }