The Tor Browser / file diff

     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/media/libvpx/vp8/decoder/dboolhuff.c	Wed Dec 31 06:09:35 2014 +0100
     1.3 @@ -0,0 +1,75 @@
     1.4 +/*
     1.5 + *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
     1.6 + *
     1.7 + *  Use of this source code is governed by a BSD-style license
     1.8 + *  that can be found in the LICENSE file in the root of the source
     1.9 + *  tree. An additional intellectual property rights grant can be found
    1.10 + *  in the file PATENTS.  All contributing project authors may
    1.11 + *  be found in the AUTHORS file in the root of the source tree.
    1.12 + */
    1.13 +
    1.14 +
    1.15 +#include "dboolhuff.h"
    1.16 +
    1.17 +int vp8dx_start_decode(BOOL_DECODER *br,
    1.18 +                       const unsigned char *source,
    1.19 +                       unsigned int source_sz,
    1.20 +                       vp8_decrypt_cb *decrypt_cb,
    1.21 +                       void *decrypt_state)
    1.22 +{
    1.23 +    br->user_buffer_end = source+source_sz;
    1.24 +    br->user_buffer     = source;
    1.25 +    br->value    = 0;
    1.26 +    br->count    = -8;
    1.27 +    br->range    = 255;
    1.28 +    br->decrypt_cb = decrypt_cb;
    1.29 +    br->decrypt_state = decrypt_state;
    1.30 +
    1.31 +    if (source_sz && !source)
    1.32 +        return 1;
    1.33 +
    1.34 +    /* Populate the buffer */
    1.35 +    vp8dx_bool_decoder_fill(br);
    1.36 +
    1.37 +    return 0;
    1.38 +}
    1.39 +
    1.40 +void vp8dx_bool_decoder_fill(BOOL_DECODER *br)
    1.41 +{
    1.42 +    const unsigned char *bufptr = br->user_buffer;
    1.43 +    VP8_BD_VALUE value = br->value;
    1.44 +    int count = br->count;
    1.45 +    int shift = VP8_BD_VALUE_SIZE - 8 - (count + 8);
    1.46 +    size_t bytes_left = br->user_buffer_end - bufptr;
    1.47 +    size_t bits_left = bytes_left * CHAR_BIT;
    1.48 +    int x = (int)(shift + CHAR_BIT - bits_left);
    1.49 +    int loop_end = 0;
    1.50 +    unsigned char decrypted[sizeof(VP8_BD_VALUE) + 1];
    1.51 +
    1.52 +    if (br->decrypt_cb) {
    1.53 +        size_t n = bytes_left > sizeof(decrypted) ? sizeof(decrypted) : bytes_left;
    1.54 +        br->decrypt_cb(br->decrypt_state, bufptr, decrypted, (int)n);
    1.55 +        bufptr = decrypted;
    1.56 +    }
    1.57 +
    1.58 +    if(x >= 0)
    1.59 +    {
    1.60 +        count += VP8_LOTS_OF_BITS;
    1.61 +        loop_end = x;
    1.62 +    }
    1.63 +
    1.64 +    if (x < 0 || bits_left)
    1.65 +    {
    1.66 +        while(shift >= loop_end)
    1.67 +        {
    1.68 +            count += CHAR_BIT;
    1.69 +            value |= (VP8_BD_VALUE)*bufptr << shift;
    1.70 +            ++bufptr;
    1.71 +            ++br->user_buffer;
    1.72 +            shift -= CHAR_BIT;
    1.73 +        }
    1.74 +    }
    1.75 +
    1.76 +    br->value = value;
    1.77 +    br->count = count;
    1.78 +}