/*
  * VC-1 and WMV3 decoder
  * Copyright (c) 2006-2007 Konstantin Shishkov
  * Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer
  *

  * 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
  */
 
 #ifndef AVCODEC_VC1_COMMON_H
 #define AVCODEC_VC1_COMMON_H
 
 #include <stdint.h>
 
 #include "libavutil/attributes.h"
 
 /** Markers used in VC-1 AP frame data */
 //@{
 enum VC1Code {
     VC1_CODE_RES0       = 0x00000100,
     VC1_CODE_ENDOFSEQ   = 0x0000010A,
     VC1_CODE_SLICE,
     VC1_CODE_FIELD,
     VC1_CODE_FRAME,
     VC1_CODE_ENTRYPOINT,
     VC1_CODE_SEQHDR,
 };
 //@}
 
 #define IS_MARKER(x) (((x) & ~0xFF) == VC1_CODE_RES0)
 
 /** Available Profiles */
 //@{
 enum Profile {
     PROFILE_SIMPLE,
     PROFILE_MAIN,
     PROFILE_COMPLEX, ///< TODO: WMV9 specific
     PROFILE_ADVANCED
 };
 //@}
 
 /** Find VC-1 marker in buffer
  * @return position where next marker starts or end of buffer if no marker found
  */
 static av_always_inline const uint8_t* find_next_marker(const uint8_t *src, const uint8_t *end)
 {
     uint32_t mrk = 0xFFFFFFFF;
 
     if (end-src < 4)
         return end;
     while (src < end) {
         mrk = (mrk << 8) | *src++;
         if (IS_MARKER(mrk))
             return src - 4;
     }
     return end;
 }
 
 static av_always_inline int vc1_unescape_buffer(const uint8_t *src, int size, uint8_t *dst)
 {
     int dsize = 0, i;
 
     if (size < 4) {
         for (dsize = 0; dsize < size; dsize++)
             *dst++ = *src++;
         return size;
     }
     for (i = 0; i < size; i++, src++) {
         if (src[0] == 3 && i >= 2 && !src[-1] && !src[-2] && i < size-1 && src[1] < 4) {
             dst[dsize++] = src[1];
             src++;
             i++;
         } else
             dst[dsize++] = *src;
     }
     return dsize;
 }
 
 #endif /* AVCODEC_VC1_COMMON_H */