libavcodec/bytestream.h

   1 /*
   2  * Bytestream functions
   3  * copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@free.fr>
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef AVCODEC_BYTESTREAM_H
  23 #define AVCODEC_BYTESTREAM_H
  24
  25 #include <string.h>
  26 #include "libavutil/common.h"
  27 #include "libavutil/intreadwrite.h"
  28
  29 #define DEF_T(type, name, bytes, read, write)                             \
  30 static av_always_inline type bytestream_get_ ## name(const uint8_t **b){\
  31     (*b) += bytes;\
  32     return read(*b - bytes);\
  33 }\
  34 static av_always_inline void bytestream_put_ ##name(uint8_t **b, const type value){\
  35     write(*b, value);\
  36     (*b) += bytes;\
  37 }
  38
  39 #define DEF(name, bytes, read, write) \
  40     DEF_T(unsigned int, name, bytes, read, write)
  41 #define DEF64(name, bytes, read, write) \
  42     DEF_T(uint64_t, name, bytes, read, write)
  43
  44 DEF64(le64, 8, AV_RL64, AV_WL64)
  45 DEF  (le32, 4, AV_RL32, AV_WL32)
  46 DEF  (le24, 3, AV_RL24, AV_WL24)
  47 DEF  (le16, 2, AV_RL16, AV_WL16)
  48 DEF64(be64, 8, AV_RB64, AV_WB64)
  49 DEF  (be32, 4, AV_RB32, AV_WB32)
  50 DEF  (be24, 3, AV_RB24, AV_WB24)
  51 DEF  (be16, 2, AV_RB16, AV_WB16)
  52 DEF  (byte, 1, AV_RB8 , AV_WB8 )
  53
  54 #undef DEF
  55 #undef DEF64
  56 #undef DEF_T
  57
  58 static av_always_inline unsigned int bytestream_get_buffer(const uint8_t **b, uint8_t *dst, unsigned int size)
  59 {
  60     memcpy(dst, *b, size);
  61     (*b) += size;
  62     return size;
  63 }
  64
  65 static av_always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size)
  66 {
  67     memcpy(*b, src, size);
  68     (*b) += size;
  69 }
  70
  71 #endif /* AVCODEC_BYTESTREAM_H */